RTOS skeleton with (UNIX) POSIX calls. Reorg of stream files

47 files changed, 7492 insertions, 14 deletions

diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..2fab89e
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "lib/FreeRTOS"]
+	path = lib/FreeRTOS
+	url = https://github.com/FreeRTOS/FreeRTOS.git
diff --git a/include/FreeRTOSConfig.h b/include/FreeRTOSConfig.h
new file mode 100644
index 0000000..d511e69
--- /dev/null
+++ b/include/FreeRTOSConfig.h
@@ -0,0 +1,119 @@
+/*
+ * FreeRTOS Kernel V10.0.1
+ * Copyright (C) 2017 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://www.FreeRTOS.org
+ * http://aws.amazon.com/freertos
+ *
+ * 1 tab == 4 spaces!
+ */
+
+
+#ifndef FREERTOS_CONFIG_H
+#define FREERTOS_CONFIG_H
+
+#include <stdint.h>
+
+/*-----------------------------------------------------------
+ * Application specific definitions.
+ *
+ * These definitions should be adjusted for your particular hardware and
+ * application requirements.
+ *
+ * THESE PARAMETERS ARE DESCRIBED WITHIN THE 'CONFIGURATION' SECTION OF THE
+ * FreeRTOS API DOCUMENTATION AVAILABLE ON THE FreeRTOS.org WEB SITE.
+ * http://www.freertos.org/a00110.html
+ *----------------------------------------------------------*/
+
+#define configUSE_PREEMPTION			1
+#define configTICK_RATE_HZ				( 1000 ) /* In this non-real time simulated environment the tick frequency has to be at least a multiple of the Win32 tick frequency, and therefore very slow. */
+#define configMINIMAL_STACK_SIZE		( ( unsigned short ) 60 ) /* In this simulated case, the stack only has to hold one small structure as the real stack is part of the Win32 thread. */
+#define configMAX_TASK_NAME_LEN			( 7 )
+#define configUSE_TRACE_FACILITY		0
+#define configUSE_16_BIT_TICKS			0
+#define configIDLE_SHOULD_YIELD			1
+#define configUSE_CO_ROUTINES 			0
+#define configUSE_MUTEXES				1
+#define configCHECK_FOR_STACK_OVERFLOW	0 /* Not applicable to the Win32 port. */
+#define configUSE_RECURSIVE_MUTEXES		1
+#define configQUEUE_REGISTRY_SIZE		0
+#define configUSE_APPLICATION_TASK_TAG	1
+#define configUSE_COUNTING_SEMAPHORES	1
+#define configUSE_ALTERNATIVE_API		0
+
+#define configUSE_TIMERS				1
+#define configTIMER_TASK_PRIORITY		2
+#define configTIMER_QUEUE_LENGTH		20
+#define configTIMER_TASK_STACK_DEPTH	( configMINIMAL_STACK_SIZE * 2 )
+
+#define configMAX_PRIORITIES			( 7 )
+#define configMAX_CO_ROUTINE_PRIORITIES ( 2 )
+
+/* Hook functions */
+#define configUSE_IDLE_HOOK				0
+#define configUSE_TICK_HOOK				0
+#define configUSE_MALLOC_FAILED_HOOK	1
+
+/* Co-routine definitions. */
+#define configUSE_CO_ROUTINES 			0
+
+/* Set the following definitions to 1 to include the API function, or zero
+to exclude the API function. */
+#define INCLUDE_vTaskPrioritySet                1
+#define INCLUDE_uxTaskPriorityGet               1
+#define INCLUDE_vTaskDelete                     1
+#define INCLUDE_vTaskCleanUpResources           0
+#define INCLUDE_vTaskSuspend                    1
+#define INCLUDE_vTaskDelayUntil                 1
+#define INCLUDE_vTaskDelay                      1
+#define INCLUDE_uxTaskGetStackHighWaterMark     1
+#define INCLUDE_xTaskGetSchedulerState          1
+#define INCLUDE_xTimerGetTimerTaskHandle        0
+#define INCLUDE_xTaskGetIdleTaskHandle          0
+#define INCLUDE_xQueueGetMutexHolder            1
+#define INCLUDE_eTaskGetState                   1
+#define INCLUDE_xEventGroupSetBitsFromISR       1
+#define INCLUDE_xTimerPendFunctionCall          1
+#define INCLUDE_xTaskGetCurrentTaskHandle       1
+#define INCLUDE_xTaskAbortDelay                 1
+
+/* heap_4.c,  */
+#define configTOTAL_HEAP_SIZE				( ( size_t ) ( 2048U * 1024U ) )
+
+/* Allow RTOS objects to be created using RAM provided by the application writer. */
+#define configSUPPORT_STATIC_ALLOCATION         1
+
+/*  Create RTOS objects using dynamically allocated RAM */
+#define configSUPPORT_DYNAMIC_ALLOCATION		1
+
+/* This demo makes use of one or more example stats formatting functions.  These
+format the raw data provided by the uxTaskGetSystemState() function in to human
+readable ASCII form.  See the notes in the implementation of vTaskList() within
+FreeRTOS/Source/tasks.c for limitations. */
+#define configUSE_STATS_FORMATTING_FUNCTIONS	1
+
+/* Run time stats gathering definitions. */
+#define configGENERATE_RUN_TIME_STATS	0
+
+/* Assert call defined for debug builds. */
+extern void vAssertCalled(const char * pcFile, uint32_t ulLine);
+#define configASSERT( x )    if( ( x ) == 0 ) vAssertCalled( __FILE__, __LINE__ )
+
+#endif /* FREERTOS_CONFIG_H */
diff --git a/include/master_posix.h b/include/master_posix.h
new file mode 100644
index 0000000..c207d3f
--- /dev/null
+++ b/include/master_posix.h
@@ -0,0 +1,6 @@
+#ifndef _MASTER_POSIX_H_
+#define _MASTER_POSIX_H_
+
+void vStartPOSIXMaster(void *pvParameters);
+
+#endif /* _MASTER_POSIX_H_ */
diff --git a/lib/FreeRTOS b/lib/FreeRTOS
new file mode 160000
+Subproject 08af68ef9049279b265c3d00e9c48fb9594129a
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX.h
new file mode 100755
index 0000000..d938709
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX.h
@@ -0,0 +1,50 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX.h
+ * @brief FreeRTOS+POSIX header.
+ *
+ * This file must be included before all other FreeRTOS+POSIX includes.
+ */
+
+#ifndef _FREERTOS_POSIX_H_
+#define _FREERTOS_POSIX_H_
+
+/* FreeRTOS+POSIX platform-specific configuration headers. */
+#include "FreeRTOS_POSIX_portable.h"
+#include "FreeRTOS_POSIX_portable_default.h"
+
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "event_groups.h"
+#include "semphr.h"
+#include "task.h"
+
+/* FreeRTOS+POSIX data types and internal structs. */
+#include "FreeRTOS_POSIX/sys/types.h"
+#include "FreeRTOS_POSIX_internal.h"
+
+#endif /* _FREERTOS_POSIX_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX_internal.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX_internal.h
new file mode 100755
index 0000000..16f8036
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX_internal.h
@@ -0,0 +1,129 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+#ifndef _FREERTOS_POSIX_INTERNAL_H_
+#define _FREERTOS_POSIX_INTERNAL_H_
+
+/**
+ * @file FreeRTOS_POSIX_internal.h
+ * @brief Internal structs and initializers for FreeRTOS+POSIX.
+ */
+
+/* Amazon FreeRTOS includes. */
+#include "iot_doubly_linked_list.h"
+
+/**
+ * @brief Mutex attribute object.
+ */
+#if posixconfigENABLE_PTHREAD_MUTEXATTR_T == 1
+    typedef struct pthread_mutexattr_internal
+    {
+        int iType; /**< Mutex type. */
+    } pthread_mutexattr_internal_t;
+#endif
+
+#if posixconfigENABLE_PTHREAD_MUTEX_T == 1
+
+/**
+ * @brief Mutex.
+ */
+    typedef struct pthread_mutex_internal
+    {
+        BaseType_t xIsInitialized;          /**< Set to pdTRUE if this mutex is initialized, pdFALSE otherwise. */
+        StaticSemaphore_t xMutex;           /**< FreeRTOS mutex. */
+        TaskHandle_t xTaskOwner;            /**< Owner; used for deadlock detection and permission checks. */
+        pthread_mutexattr_internal_t xAttr; /**< Mutex attributes. */
+    } pthread_mutex_internal_t;
+
+/**
+ * @brief Compile-time initializer of pthread_mutex_internal_t.
+ */
+    #define FREERTOS_POSIX_MUTEX_INITIALIZER \
+    ( ( ( pthread_mutex_internal_t )         \
+    {                                        \
+        .xIsInitialized = pdFALSE,           \
+        .xMutex = { { 0 } },                 \
+        .xTaskOwner = NULL,                  \
+        .xAttr = { .iType = 0 }              \
+    }                                        \
+        )                                    \
+    )
+#endif /* if posixconfigENABLE_PTHREAD_MUTEX_T == 1 */
+
+#if posixconfigENABLE_PTHREAD_COND_T == 1
+
+/**
+ * @brief Condition variable.
+ */
+    typedef struct pthread_cond_internal
+    {
+        BaseType_t xIsInitialized;            /**< Set to pdTRUE if this condition variable is initialized, pdFALSE otherwise. */
+        StaticSemaphore_t xCondWaitSemaphore; /**< Threads block on this semaphore in pthread_cond_wait. */
+        unsigned iWaitingThreads;             /**< The number of threads currently waiting on this condition variable. */
+    } pthread_cond_internal_t;
+
+/**
+ * @brief Compile-time initializer of pthread_cond_internal_t.
+ */
+
+    #define FREERTOS_POSIX_COND_INITIALIZER \
+    ( ( ( pthread_cond_internal_t )         \
+    {                                       \
+        .xIsInitialized = pdFALSE,          \
+        .xCondWaitSemaphore = { { 0 } },    \
+        .iWaitingThreads = 0                \
+    }                                       \
+        )                                   \
+    )
+
+#endif /* if posixconfigENABLE_PTHREAD_COND_T == 1 */
+
+#if posixconfigENABLE_SEM_T == 1
+
+/**
+ * @brief Semaphore type.
+ */
+    typedef struct
+    {
+        StaticSemaphore_t xSemaphore; /**< FreeRTOS semaphore. */
+        int value;                    /**< POSIX semaphore count. */
+    } sem_internal_t;
+#endif /* if posixconfigENABLE_SEM_T == 1 */
+
+#if posixconfigENABLE_PTHREAD_BARRIER_T == 1
+
+/**
+ * @brief Barrier object.
+ */
+    typedef struct pthread_barrier_internal
+    {
+        unsigned uThreadCount;                   /**< Current number of threads that have entered barrier. */
+        unsigned uThreshold;                     /**< The count argument of pthread_barrier_init. */
+        StaticSemaphore_t xThreadCountSemaphore; /**< Prevents more than uThreshold threads from exiting pthread_barrier_wait at once. */
+        StaticEventGroup_t xBarrierEventGroup;   /**< FreeRTOS event group that blocks to wait on threads entering barrier. */
+    } pthread_barrier_internal_t;
+#endif /* if posixconfigENABLE_PTHREAD_BARRIER_T == 1 */
+
+#endif /* _FREERTOS_POSIX_INTERNAL_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX_types.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX_types.h
new file mode 100755
index 0000000..3b45b8d
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/FreeRTOS_POSIX_types.h
@@ -0,0 +1,81 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+#ifndef _FREERTOS_POSIX_INTERNAL_TYPES_H_
+#define _FREERTOS_POSIX_INTERNAL_TYPES_H_
+
+#include "FreeRTOS_POSIX_internal.h"
+
+/*
+ * sys/types.h defines a POSIX type when posixconfigENABLE_PTHREAD_<TYPE>_T
+ * is not defined AND when posixconfigENABLE_PTHREAD_<TYPE>_T is set to 1.
+ * FreeRTOS_POSIX_internal.h defines internal type ONLY when
+ * posixconfigENABLE_PTHREAD_<TYPE>_T is set to 1.
+ * #else part below is to have a type defined, so the code compiles, when
+ * posixconfigENABLE_PTHREAD_<TYPE>_T is not defined.
+ */
+#if posixconfigENABLE_PTHREAD_MUTEX_T == 1
+    typedef pthread_mutex_internal_t   PthreadMutexType_t;
+#else
+    typedef void                       * PthreadMutexType_t;
+#endif
+
+#if posixconfigENABLE_PTHREAD_COND_T == 1
+    typedef pthread_cond_internal_t    PthreadCondType_t;
+#else
+    typedef void                       * PthreadCondType_t;
+#endif
+
+#if posixconfigENABLE_SEM_T == 1
+    typedef sem_internal_t             PosixSemType_t;
+#else
+    typedef void                       * PosixSemType_t;
+#endif
+
+#if posixconfigENABLE_PTHREAD_MUTEXATTR_T == 1
+    typedef struct pthread_mutexattr
+    {
+        uint32_t ulpthreadMutexAttrStorage;
+    } PthreadMutexAttrType_t;
+#else
+    typedef void * PthreadMutexAttrType_t;
+#endif
+
+#if posixconfigENABLE_PTHREAD_ATTR_T == 1
+    typedef struct pthread_attr
+    {
+        uint32_t ulpthreadAttrStorage;
+    } PthreadAttrType_t;
+#else
+    typedef void                       * PthreadAttrType_t;
+#endif
+
+#if posixconfigENABLE_PTHREAD_BARRIER_T == 1
+    typedef pthread_barrier_internal_t PthreadBarrierType_t;
+#else
+    typedef void                       * PthreadBarrierType_t;
+#endif
+
+#endif /* _FREERTOS_POSIX_INTERNAL_TYPES_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/FreeRTOS_POSIX_portable_default.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/FreeRTOS_POSIX_portable_default.h
new file mode 100755
index 0000000..763b901
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/FreeRTOS_POSIX_portable_default.h
@@ -0,0 +1,145 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable_default.h
+ * @brief Defaults for port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_DEFAULT_H_
+#define _FREERTOS_POSIX_PORTABLE_DEFAULT_H_
+
+/**
+ * @name The FreeRTOS task name given to pthreads.
+ */
+/**@{ */
+#ifndef posixconfigPTHREAD_TASK_NAME
+    #define posixconfigPTHREAD_TASK_NAME    "pthread" /**< Task name. */
+#endif
+/**@} */
+
+/**
+ * @name the FreeRTOS timer name given to POSIX timers.
+ */
+/**@{ */
+#ifndef posixconfigTIMER_NAME
+    #define posixconfigTIMER_NAME    "timer" /**< Timer name. */
+#endif
+/**@} */
+
+/**
+ * @name Defaults for POSIX message queue implementation.
+ */
+/**@{ */
+#ifndef posixconfigMQ_MAX_MESSAGES
+    #define posixconfigMQ_MAX_MESSAGES    10 /**< Maximum number of messages in an mq at one time. */
+#endif
+
+#ifndef posixconfigMQ_MAX_SIZE
+    #define posixconfigMQ_MAX_SIZE    128 /**< Maximum size (in bytes) of each message. */
+#endif
+/**@} */
+
+/**
+ * @name POSIX implementation-dependent constants usually defined in limits.h.
+ *
+ * They are defined here to provide portability between platforms.
+ */
+/**@{ */
+#ifndef PTHREAD_STACK_MIN
+    #define PTHREAD_STACK_MIN    configMINIMAL_STACK_SIZE * sizeof( StackType_t ) /**< Minimum size in bytes of thread stack storage. */
+#endif
+#ifndef NAME_MAX
+    #define NAME_MAX             64                                               /**< Maximum number of bytes in a filename (not including terminating null). */
+#endif
+#ifndef SEM_VALUE_MAX
+    #define SEM_VALUE_MAX        0x7FFFU                                          /**< Maximum value of a sem_t. */
+#endif
+/**@} */
+
+/**
+ * @name Enable typedefs of POSIX types.
+ *
+ * Set these values to 1 or 0 to enable or disable the typedefs, respectively.
+ * These typedefs should only be disabled if they conflict with system typedefs.
+ */
+/**@{ */
+#ifndef posixconfigENABLE_CLOCK_T
+    #define posixconfigENABLE_CLOCK_T                1 /**< clock_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_CLOCKID_T
+    #define posixconfigENABLE_CLOCKID_T              1 /**< clockid_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_MODE_T
+    #define posixconfigENABLE_MODE_T                 1 /**< mode_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PID_T
+    #define posixconfigENABLE_PID_T                  1 /**< pid_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_ATTR_T
+    #define posixconfigENABLE_PTHREAD_ATTR_T         1 /**< pthread_attr_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_COND_T
+    #define posixconfigENABLE_PTHREAD_COND_T         1 /**< pthread_cond_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_CONDATTR_T
+    #define posixconfigENABLE_PTHREAD_CONDATTR_T     1 /**< pthread_condattr_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_MUTEX_T
+    #define posixconfigENABLE_PTHREAD_MUTEX_T        1 /**< pthread_mutex_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_MUTEXATTR_T
+    #define posixconfigENABLE_PTHREAD_MUTEXATTR_T    1 /**< pthread_mutexattr_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_T
+    #define posixconfigENABLE_PTHREAD_T              1 /**< pthread_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_SSIZE_T
+    #define posixconfigENABLE_SSIZE_T                1 /**< ssize_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_TIME_T
+    #define posixconfigENABLE_TIME_T                 1 /**< time_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_TIMER_T
+    #define posixconfigENABLE_TIMER_T                1 /**< timer_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_USECONDS_T
+    #define posixconfigENABLE_USECONDS_T             1 /**< useconds_t in sys/types.h */
+#endif
+#ifndef posixconfigENABLE_TIMESPEC
+    #define posixconfigENABLE_TIMESPEC               1 /**< struct timespec in time.h */
+#endif
+#ifndef posixconfigENABLE_ITIMERSPEC
+    #define posixconfigENABLE_ITIMERSPEC             1 /**< struct itimerspec in time.h */
+#endif
+#ifndef posixconfigENABLE_SEM_T
+    #define posixconfigENABLE_SEM_T                  1 /**< struct sem_t in semaphore.h */
+#endif
+#ifndef posixconfigENABLE_PTHREAD_BARRIER_T
+    #define posixconfigENABLE_PTHREAD_BARRIER_T      1 /**< pthread_barrier_t in sys/types.h */
+#endif
+/**@} */
+
+#endif /* ifndef _FREERTOS_POSIX_PORTABLE_DEFAULT_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/espressif/esp32_devkitc_esp_wrover_kit/FreeRTOS_POSIX_portable.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/espressif/esp32_devkitc_esp_wrover_kit/FreeRTOS_POSIX_portable.h
new file mode 100755
index 0000000..c187043
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/espressif/esp32_devkitc_esp_wrover_kit/FreeRTOS_POSIX_portable.h
@@ -0,0 +1,60 @@
+/*
+ * Amazon FreeRTOS+POSIX V1.0.4
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable.h
+ * @brief Port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_H_
+#define _FREERTOS_POSIX_PORTABLE_H_
+
+/* ESP-IDF already defines the following types. */
+#define posixconfigENABLE_CLOCK_T                0
+#define posixconfigENABLE_CLOCKID_T              0
+#define posixconfigENABLE_MODE_T                 0
+#define posixconfigENABLE_PTHREAD_ATTR_T         0
+#define posixconfigENABLE_PTHREAD_COND_T         0
+#define posixconfigENABLE_PTHREAD_CONDATTR_T     0
+#define posixconfigENABLE_PTHREAD_MUTEX_T        0
+#define posixconfigENABLE_PTHREAD_MUTEXATTR_T    0
+#define posixconfigENABLE_PTHREAD_T              0
+#define posixconfigENABLE_TIME_T                 0
+#define posixconfigENABLE_TIMESPEC               0
+#define posixconfigENABLE_ITIMERSPEC             0
+
+/* ESP-IDF already provides the header sched.h. Exclude FreeRTOS+POSIX sched.h by
+ * defining its double inclusion guard. */
+#define _FREERTOS_POSIX_SCHED_H_
+
+/* Use the FreeRTOS+POSIX time.h header instead of the ESP-IDF time.h. Disable
+ * ESP-IDF time.h by defining its double inclusion guard. */
+#define _TIME_H_
+
+/* Disable the timer_t type defined by ESP-IDF. */
+#define __timer_t_defined
+#include <sys/types.h>
+
+#endif /* _FREERTOS_POSIX_PORTABLE_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/microchip/curiosity_pic32mzef/FreeRTOS_POSIX_portable.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/microchip/curiosity_pic32mzef/FreeRTOS_POSIX_portable.h
new file mode 100755
index 0000000..d4d2db7
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/microchip/curiosity_pic32mzef/FreeRTOS_POSIX_portable.h
@@ -0,0 +1,50 @@
+/*
+ * Amazon FreeRTOS+POSIX V1.0.4
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable.h
+ * @brief Port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_H_
+#define _FREERTOS_POSIX_PORTABLE_H_
+
+/* Microchip includes. */
+#include <sys/types.h>
+
+/* Microchip already typedefs the following types. */
+#define posixconfigENABLE_MODE_T        0
+#define posixconfigENABLE_PID_T         0
+#define posixconfigENABLE_SSIZE_T       0
+#define posixconfigENABLE_USECONDS_T    0
+/* Microchip -mnewlib compiler option supports these types. */
+#define posixconfigENABLE_TIMESPEC      0
+#define posixconfigENABLE_ITIMERSPEC    0
+#define posixconfigENABLE_CLOCKID_T     0
+#define posixconfigENABLE_TIME_T        0
+#define posixconfigENABLE_TIMER_T       0
+
+
+#endif /* _FREERTOS_POSIX_PORTABLE_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/nxp/lpc54018iotmodule/FreeRTOS_POSIX_portable.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/nxp/lpc54018iotmodule/FreeRTOS_POSIX_portable.h
new file mode 100755
index 0000000..1022f4b
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/nxp/lpc54018iotmodule/FreeRTOS_POSIX_portable.h
@@ -0,0 +1,37 @@
+/*
+ * Amazon FreeRTOS+POSIX V1.0.4
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable.h
+ * @brief Port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_H_
+#define _FREERTOS_POSIX_PORTABLE_H_
+
+/* This port uses the defaults in FreeRTOS_POSIX_portable_default.h, so this
+ * file is empty. */
+
+#endif /* _FREERTOS_POSIX_PORTABLE_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/pc/windows/FreeRTOS_POSIX_portable.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/pc/windows/FreeRTOS_POSIX_portable.h
new file mode 100755
index 0000000..1022f4b
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/pc/windows/FreeRTOS_POSIX_portable.h
@@ -0,0 +1,37 @@
+/*
+ * Amazon FreeRTOS+POSIX V1.0.4
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable.h
+ * @brief Port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_H_
+#define _FREERTOS_POSIX_PORTABLE_H_
+
+/* This port uses the defaults in FreeRTOS_POSIX_portable_default.h, so this
+ * file is empty. */
+
+#endif /* _FREERTOS_POSIX_PORTABLE_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/st/stm32l475_discovery/FreeRTOS_POSIX_portable.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/st/stm32l475_discovery/FreeRTOS_POSIX_portable.h
new file mode 100755
index 0000000..1022f4b
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/st/stm32l475_discovery/FreeRTOS_POSIX_portable.h
@@ -0,0 +1,37 @@
+/*
+ * Amazon FreeRTOS+POSIX V1.0.4
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable.h
+ * @brief Port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_H_
+#define _FREERTOS_POSIX_PORTABLE_H_
+
+/* This port uses the defaults in FreeRTOS_POSIX_portable_default.h, so this
+ * file is empty. */
+
+#endif /* _FREERTOS_POSIX_PORTABLE_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/ti/cc3220_launchpad/FreeRTOS_POSIX_portable.h b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/ti/cc3220_launchpad/FreeRTOS_POSIX_portable.h
new file mode 100755
index 0000000..1022f4b
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/include/portable/ti/cc3220_launchpad/FreeRTOS_POSIX_portable.h
@@ -0,0 +1,37 @@
+/*
+ * Amazon FreeRTOS+POSIX V1.0.4
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_portable.h
+ * @brief Port-specific configuration of FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_PORTABLE_H_
+#define _FREERTOS_POSIX_PORTABLE_H_
+
+/* This port uses the defaults in FreeRTOS_POSIX_portable_default.h, so this
+ * file is empty. */
+
+#endif /* _FREERTOS_POSIX_PORTABLE_H_ */
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_clock.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_clock.c
new file mode 100755
index 0000000..51e592a
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_clock.c
@@ -0,0 +1,240 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_clock.c
+ * @brief Implementation of clock functions in time.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+#include <string.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/time.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+/* Declaration of snprintf. The header stdio.h is not included because it
+ * includes conflicting symbols on some platforms. */
+extern int snprintf( char * s,
+                     size_t n,
+                     const char * format,
+                     ... );
+
+/*-----------------------------------------------------------*/
+
+clock_t clock( void )
+{
+    /* This function is currently unsupported. It will always return -1. */
+
+    return ( clock_t ) -1;
+}
+
+/*-----------------------------------------------------------*/
+
+int clock_getcpuclockid( pid_t pid,
+                         clockid_t * clock_id )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) pid;
+    ( void ) clock_id;
+
+    /* This function is currently unsupported. It will always return EPERM. */
+    return EPERM;
+}
+
+/*-----------------------------------------------------------*/
+
+int clock_getres( clockid_t clock_id,
+                  struct timespec * res )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) clock_id;
+
+    /* Convert FreeRTOS tick resolution as timespec. */
+    if( res != NULL )
+    {
+        res->tv_sec = 0;
+        res->tv_nsec = NANOSECONDS_PER_TICK;
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int clock_gettime( clockid_t clock_id,
+                   struct timespec * tp )
+{
+    TimeOut_t xCurrentTime = { 0 };
+
+    /* Intermediate variable used to convert TimeOut_t to struct timespec.
+     * Also used to detect overflow issues. It must be unsigned because the
+     * behavior of signed integer overflow is undefined. */
+    uint64_t ullTickCount = 0ULL;
+
+    /* Silence warnings about unused parameters. */
+    ( void ) clock_id;
+
+    /* Get the current tick count and overflow count. vTaskSetTimeOutState()
+     * is used to get these values because they are both static in tasks.c. */
+    vTaskSetTimeOutState( &xCurrentTime );
+
+    /* Adjust the tick count for the number of times a TickType_t has overflowed.
+     * portMAX_DELAY should be the maximum value of a TickType_t. */
+    ullTickCount = ( uint64_t ) ( xCurrentTime.xOverflowCount ) << ( sizeof( TickType_t ) * 8 );
+
+    /* Add the current tick count. */
+    ullTickCount += xCurrentTime.xTimeOnEntering;
+
+    /* Convert ullTickCount to timespec. */
+    UTILS_NanosecondsToTimespec( ( int64_t ) ullTickCount * NANOSECONDS_PER_TICK, tp );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int clock_nanosleep( clockid_t clock_id,
+                     int flags,
+                     const struct timespec * rqtp,
+                     struct timespec * rmtp )
+{
+    int iStatus = 0;
+    TickType_t xSleepTime = 0;
+    struct timespec xCurrentTime = { 0 };
+
+    /* Silence warnings about unused parameters. */
+    ( void ) clock_id;
+    ( void ) rmtp;
+    ( void ) flags; /* This is only ignored if INCLUDE_vTaskDelayUntil is 0. */
+
+    /* Check rqtp. */
+    if( UTILS_ValidateTimespec( rqtp ) == false )
+    {
+        iStatus = EINVAL;
+    }
+
+    /* Get current time */
+    if( ( iStatus == 0 ) && ( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 ) )
+    {
+        iStatus = EINVAL;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Check for absolute time sleep. */
+        if( ( flags & TIMER_ABSTIME ) == TIMER_ABSTIME )
+        {
+            /* Get current time */
+            if( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 )
+            {
+                iStatus = EINVAL;
+            }
+
+            /* Get number of ticks until absolute time. */
+            if( ( iStatus == 0 ) && ( UTILS_AbsoluteTimespecToDeltaTicks( rqtp, &xCurrentTime, &xSleepTime ) == 0 ) )
+            {
+                /* Delay until absolute time if vTaskDelayUntil is available. */
+                #if ( INCLUDE_vTaskDelayUntil == 1 )
+
+                    /* Get the current tick count. This variable isn't declared
+                     * at the top of the function because it's only used and needed
+                     * if vTaskDelayUntil is available. */
+                    TickType_t xCurrentTicks = xTaskGetTickCount();
+
+                    /* Delay until absolute time. */
+                    vTaskDelayUntil( &xCurrentTicks, xSleepTime );
+                #else
+
+                    /* If vTaskDelayUntil isn't available, ignore the TIMER_ABSTIME flag
+                     * and sleep for a relative time. */
+                    vTaskDelay( xSleepTime );
+                #endif
+            }
+        }
+        else
+        {
+            /* If TIMER_ABSTIME isn't specified, convert rqtp to ticks and
+             * sleep for a relative time. */
+            if( UTILS_TimespecToTicks( rqtp, &xSleepTime ) == 0 )
+            {
+                vTaskDelay( xSleepTime );
+            }
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int clock_settime( clockid_t clock_id,
+                   const struct timespec * tp )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) clock_id;
+    ( void ) tp;
+
+    /* This function is currently unsupported. It will always return -1 and
+     * set errno to EPERM. */
+    errno = EPERM;
+
+    return -1;
+}
+
+/*-----------------------------------------------------------*/
+
+int nanosleep( const struct timespec * rqtp,
+               struct timespec * rmtp )
+{
+    int iStatus = 0;
+    TickType_t xSleepTime = 0;
+
+    /* Silence warnings about unused parameters. */
+    ( void ) rmtp;
+
+    /* Check rqtp. */
+    if( UTILS_ValidateTimespec( rqtp ) == false )
+    {
+        errno = EINVAL;
+        iStatus = -1;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Convert rqtp to ticks and delay. */
+        if( UTILS_TimespecToTicks( rqtp, &xSleepTime ) == 0 )
+        {
+            vTaskDelay( xSleepTime );
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_mqueue.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_mqueue.c
new file mode 100755
index 0000000..9f9079b
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_mqueue.c
@@ -0,0 +1,893 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_mqueue.c
+ * @brief Implementation of message queue functions in mqueue.h
+ */
+
+/* C standard library includes. */
+#include <string.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/fcntl.h"
+#include "FreeRTOS_POSIX/mqueue.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+/**
+ * @brief Element of the FreeRTOS queues that store mq data.
+ */
+typedef struct QueueElement
+{
+    char * pcData;    /**< Data in queue. Type char* to match msg_ptr. */
+    size_t xDataSize; /**< Size of data pointed by pcData. */
+} QueueElement_t;
+
+/**
+ * @brief Data structure of an mq.
+ *
+ * FreeRTOS isn't guaranteed to have a file-like abstraction, so message
+ * queues in this implementation are stored as a linked list (in RAM).
+ */
+typedef struct QueueListElement
+{
+    Link_t xLink;              /**< Pointer to the next element in the list. */
+    QueueHandle_t xQueue;      /**< FreeRTOS queue handle. */
+    size_t xOpenDescriptors;   /**< Number of threads that have opened this queue. */
+    char * pcName;             /**< Null-terminated queue name. */
+    struct mq_attr xAttr;      /**< Queue attibutes. */
+    BaseType_t xPendingUnlink; /**< If pdTRUE, this queue will be unlinked once all descriptors close. */
+} QueueListElement_t;
+
+/*-----------------------------------------------------------*/
+
+/**
+ * @brief Convert an absolute timespec into a tick timeout, taking into account
+ * queue flags.
+ *
+ * @param[in] lMessageQueueFlags Message queue flags to consider.
+ * @param[in] pxAbsoluteTimeout The absolute timespec to convert.
+ * @param[out] pxTimeoutTicks Output parameter of the timeout in ticks.
+ *
+ * @return 0 if successful; EINVAL if pxAbsoluteTimeout is invalid, or ETIMEDOUT
+ * if pxAbsoluteTimeout is in the past.
+ */
+static int prvCalculateTickTimeout( long lMessageQueueFlags,
+                                    const struct timespec * const pxAbsoluteTimeout,
+                                    TickType_t * pxTimeoutTicks );
+
+/**
+ * @brief Add a new queue to the queue list.
+ *
+ * @param[out] ppxMessageQueue Pointer to new queue.
+ * @param[in] pxAttr mq_attr of the new queue.
+ * @param[in] pcName Name of new queue.
+ * @param[in] xNameLength Length of pcName.
+ *
+ * @return pdTRUE if the queue is found; pdFALSE otherwise.
+ */
+static BaseType_t prvCreateNewMessageQueue( QueueListElement_t ** ppxMessageQueue,
+                                            const struct mq_attr * const pxAttr,
+                                            const char * const pcName,
+                                            size_t xNameLength );
+
+/**
+ * @brief Free all the resources used by a message queue.
+ *
+ * @param[out] pxMessageQueue Pointer to queue to free.
+ *
+ * @return nothing
+ */
+static void prvDeleteMessageQueue( const QueueListElement_t * const pxMessageQueue );
+
+/**
+ * @brief Attempt to find the queue identified by pcName or xMqId in the queue list.
+ *
+ * Matches queues by pcName first; if pcName is NULL, matches by xMqId.
+ * @param[out] ppxQueueListElement Output parameter set when queue is found.
+ * @param[in] pcName A queue name to match.
+ * @param[in] xMessageQueueDescriptor A queue descriptor to match.
+ *
+ * @return pdTRUE if the queue is found; pdFALSE otherwise.
+ */
+static BaseType_t prvFindQueueInList( QueueListElement_t ** const ppxQueueListElement,
+                                      const char * const pcName,
+                                      mqd_t xMessageQueueDescriptor );
+
+/**
+ * @brief Initialize the queue list.
+ *
+ * Performs initialization of the queue list mutex and queue list head.
+ *
+ * @return nothing
+ */
+static void prvInitializeQueueList( void );
+
+/**
+ * @brief Checks that pcName is a valid name for a message queue.
+ *
+ * Also outputs the length of pcName.
+ * @param[in] pcName The name to check.
+ * @param[out] pxNameLength Output parameter for name length.
+ *
+ * @return pdTRUE if the name is valid; pdFALSE otherwise.
+ */
+static BaseType_t prvValidateQueueName( const char * const pcName,
+                                        size_t * pxNameLength );
+
+/**
+ * @brief Guards access to the list of message queues.
+ */
+static StaticSemaphore_t xQueueListMutex = { { 0 }, .u = { 0 } };
+
+/**
+ * @brief Head of the linked list of queues.
+ */
+static Link_t xQueueListHead = { 0 };
+
+/*-----------------------------------------------------------*/
+
+static int prvCalculateTickTimeout( long lMessageQueueFlags,
+                                    const struct timespec * const pxAbsoluteTimeout,
+                                    TickType_t * pxTimeoutTicks )
+{
+    int iStatus = 0;
+
+    /* Check for nonblocking queue. */
+    if( lMessageQueueFlags & O_NONBLOCK )
+    {
+        /* No additional checks are done for nonblocking queues. Timeout is 0. */
+        *pxTimeoutTicks = 0;
+    }
+    else
+    {
+        /* No absolute timeout given. Block forever. */
+        if( pxAbsoluteTimeout == NULL )
+        {
+            *pxTimeoutTicks = portMAX_DELAY;
+        }
+        else
+        {
+            struct timespec xCurrentTime = { 0 };
+
+            /* Check that the given timespec is valid. */
+            if( UTILS_ValidateTimespec( pxAbsoluteTimeout ) == false )
+            {
+                iStatus = EINVAL;
+            }
+
+            /* Get current time */
+            if( ( iStatus == 0 ) && ( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 ) )
+            {
+                iStatus = EINVAL;
+            }
+
+            /* Convert absolute timespec to ticks. */
+            if( ( iStatus == 0 ) &&
+                ( UTILS_AbsoluteTimespecToDeltaTicks( pxAbsoluteTimeout, &xCurrentTime, pxTimeoutTicks ) != 0 ) )
+            {
+                iStatus = ETIMEDOUT;
+            }
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+static BaseType_t prvCreateNewMessageQueue( QueueListElement_t ** ppxMessageQueue,
+                                            const struct mq_attr * const pxAttr,
+                                            const char * const pcName,
+                                            size_t xNameLength )
+{
+    BaseType_t xStatus = pdTRUE;
+
+    /* Allocate space for a new queue element. */
+    *ppxMessageQueue = pvPortMalloc( sizeof( QueueListElement_t ) );
+
+    /* Check that memory allocation succeeded. */
+    if( *ppxMessageQueue == NULL )
+    {
+        xStatus = pdFALSE;
+    }
+
+    /* Create the FreeRTOS queue. */
+    if( xStatus == pdTRUE )
+    {
+        ( *ppxMessageQueue )->xQueue =
+            xQueueCreate( pxAttr->mq_maxmsg, sizeof( QueueElement_t ) );
+
+        /* Check that queue creation succeeded. */
+        if( ( *ppxMessageQueue )->xQueue == NULL )
+        {
+            vPortFree( *ppxMessageQueue );
+            xStatus = pdFALSE;
+        }
+    }
+
+    if( xStatus == pdTRUE )
+    {
+        /* Allocate space for the queue name plus null-terminator. */
+        ( *ppxMessageQueue )->pcName = pvPortMalloc( xNameLength + 1 );
+
+        /* Check that memory was successfully allocated for queue name. */
+        if( ( *ppxMessageQueue )->pcName == NULL )
+        {
+            vQueueDelete( ( *ppxMessageQueue )->xQueue );
+            vPortFree( *ppxMessageQueue );
+            xStatus = pdFALSE;
+        }
+        else
+        {
+            /* Copy queue name. Copying xNameLength+1 will cause strncpy to add
+             * the null-terminator. */
+            ( void ) strncpy( ( *ppxMessageQueue )->pcName, pcName, xNameLength + 1 );
+        }
+    }
+
+    if( xStatus == pdTRUE )
+    {
+        /* Copy attributes. */
+        ( *ppxMessageQueue )->xAttr = *pxAttr;
+
+        /* A newly-created queue will have 1 open descriptor for it. */
+        ( *ppxMessageQueue )->xOpenDescriptors = 1;
+
+        /* A newly-created queue will not be pending unlink. */
+        ( *ppxMessageQueue )->xPendingUnlink = pdFALSE;
+
+        /* Add the new queue to the list. */
+        listADD( &xQueueListHead, &( *ppxMessageQueue )->xLink );
+    }
+
+    return xStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+static void prvDeleteMessageQueue( const QueueListElement_t * const pxMessageQueue )
+{
+    QueueElement_t xQueueElement = { 0 };
+
+    /* Free all data in the queue. It's assumed that no more data will be added
+     * to the queue, so xQueueReceive does not block. */
+    while( xQueueReceive( pxMessageQueue->xQueue,
+                          ( void * ) &xQueueElement,
+                          0 ) == pdTRUE )
+    {
+        vPortFree( xQueueElement.pcData );
+    }
+
+    /* Free memory used by this message queue. */
+    vQueueDelete( pxMessageQueue->xQueue );
+    vPortFree( ( void * ) pxMessageQueue->pcName );
+    vPortFree( ( void * ) pxMessageQueue );
+}
+
+/*-----------------------------------------------------------*/
+
+static BaseType_t prvFindQueueInList( QueueListElement_t ** const ppxQueueListElement,
+                                      const char * const pcName,
+                                      mqd_t xMessageQueueDescriptor )
+{
+    Link_t * pxQueueListLink = NULL;
+    QueueListElement_t * pxMessageQueue = NULL;
+    BaseType_t xQueueFound = pdFALSE;
+
+    /* Iterate through the list of queues. */
+    listFOR_EACH( pxQueueListLink, &xQueueListHead )
+    {
+        pxMessageQueue = listCONTAINER( pxQueueListLink, QueueListElement_t, xLink );
+
+        /* Match by name first if provided. */
+        if( ( pcName != NULL ) && ( strcmp( pxMessageQueue->pcName, pcName ) == 0 ) )
+        {
+            xQueueFound = pdTRUE;
+            break;
+        }
+        /* If name doesn't match, match by descriptor. */
+        else
+        {
+            if( ( mqd_t ) pxMessageQueue == xMessageQueueDescriptor )
+            {
+                xQueueFound = pdTRUE;
+                break;
+            }
+        }
+    }
+
+    /* If the queue was found, set the output parameter. */
+    if( ( xQueueFound == pdTRUE ) && ( ppxQueueListElement != NULL ) )
+    {
+        *ppxQueueListElement = pxMessageQueue;
+    }
+
+    return xQueueFound;
+}
+
+/*-----------------------------------------------------------*/
+
+static void prvInitializeQueueList( void )
+{
+    /* Keep track of whether the queue list has been initialized. */
+    static BaseType_t xQueueListInitialized = pdFALSE;
+
+    /* Check if queue list needs to be initialized. */
+    if( xQueueListInitialized == pdFALSE )
+    {
+        /* Initialization must be in a critical section to prevent two threads
+         * from initializing at the same time. */
+        taskENTER_CRITICAL();
+
+        /* Check again that queue list is still uninitialized, i.e. it wasn't
+         * initialized while this function was waiting to enter the critical
+         * section. */
+        if( xQueueListInitialized == pdFALSE )
+        {
+            /* Initialize the queue list mutex and list head. */
+            ( void ) xSemaphoreCreateMutexStatic( &xQueueListMutex );
+            listINIT_HEAD( &xQueueListHead );
+            xQueueListInitialized = pdTRUE;
+        }
+
+        /* Exit the critical section. */
+        taskEXIT_CRITICAL();
+    }
+}
+
+/*-----------------------------------------------------------*/
+
+static BaseType_t prvValidateQueueName( const char * const pcName,
+                                        size_t * pxNameLength )
+{
+    BaseType_t xStatus = pdTRUE;
+    size_t xNameLength = 0;
+
+    /* All message queue names must start with '/'. */
+    if( pcName[ 0 ] != '/' )
+    {
+        xStatus = pdFALSE;
+    }
+    else
+    {
+        /* Get the length of pcName, excluding the first '/' and null-terminator. */
+        xNameLength = UTILS_strnlen( pcName, NAME_MAX + 2 );
+
+        if( xNameLength == NAME_MAX + 2 )
+        {
+            /* Name too long. */
+            xStatus = pdFALSE;
+        }
+        else
+        {
+            /* Name length passes, set output parameter. */
+            *pxNameLength = xNameLength;
+        }
+    }
+
+    return xStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int mq_close( mqd_t mqdes )
+{
+    int iStatus = 0;
+    QueueListElement_t * pxMessageQueue = ( QueueListElement_t * ) mqdes;
+    BaseType_t xQueueRemoved = pdFALSE;
+
+    /* Initialize the queue list, if needed. */
+    prvInitializeQueueList();
+
+    /* Lock the mutex that guards access to the queue list. This call will
+     * never fail because it blocks forever. */
+    ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );
+
+    /* Attempt to find the message queue based on the given descriptor. */
+    if( prvFindQueueInList( NULL, NULL, mqdes ) == pdTRUE )
+    {
+        /* Decrement the number of open descriptors. */
+        if( pxMessageQueue->xOpenDescriptors > 0 )
+        {
+            pxMessageQueue->xOpenDescriptors--;
+        }
+
+        /* Check if the queue has any more open descriptors. */
+        if( pxMessageQueue->xOpenDescriptors == 0 )
+        {
+            /* If no open descriptors remain and mq_unlink has already been called,
+             * remove the queue. */
+            if( pxMessageQueue->xPendingUnlink == pdTRUE )
+            {
+                listREMOVE( &pxMessageQueue->xLink );
+
+                /* Set the flag to delete the queue. Deleting the queue is deferred
+                 * until xQueueListMutex is released. */
+                xQueueRemoved = pdTRUE;
+            }
+            /* Otherwise, wait for the call to mq_unlink. */
+            else
+            {
+                pxMessageQueue->xPendingUnlink = pdTRUE;
+            }
+        }
+    }
+    else
+    {
+        /* Queue not found; bad descriptor. */
+        errno = EBADF;
+        iStatus = -1;
+    }
+
+    /* Release the mutex protecting the queue list. */
+    ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
+
+    /* Delete all resources used by the queue if needed. */
+    if( xQueueRemoved == pdTRUE )
+    {
+        prvDeleteMessageQueue( pxMessageQueue );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int mq_getattr( mqd_t mqdes,
+                struct mq_attr * mqstat )
+{
+    int iStatus = 0;
+    QueueListElement_t * pxMessageQueue = ( QueueListElement_t * ) mqdes;
+
+    /* Lock the mutex that guards access to the queue list. This call will
+     * never fail because it blocks forever. */
+    ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );
+
+    /* Find the mq referenced by mqdes. */
+    if( prvFindQueueInList( NULL, NULL, mqdes ) == pdTRUE )
+    {
+        /* Update the number of messages in the queue and copy the attributes
+         * into mqstat. */
+        pxMessageQueue->xAttr.mq_curmsgs = ( long ) uxQueueMessagesWaiting( pxMessageQueue->xQueue );
+        *mqstat = pxMessageQueue->xAttr;
+    }
+    else
+    {
+        /* Queue not found; bad descriptor. */
+        errno = EBADF;
+        iStatus = -1;
+    }
+
+    /* Release the mutex protecting the queue list. */
+    ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+mqd_t mq_open( const char * name,
+               int oflag,
+               mode_t mode,
+               struct mq_attr * attr )
+{
+    mqd_t xMessageQueue = NULL;
+    size_t xNameLength = 0;
+
+    /* Default mq_attr. */
+    struct mq_attr xQueueCreationAttr =
+    {
+        .mq_flags   = 0,
+        .mq_maxmsg  = posixconfigMQ_MAX_MESSAGES,
+        .mq_msgsize = posixconfigMQ_MAX_SIZE,
+        .mq_curmsgs = 0
+    };
+
+    /* Silence warnings about unused parameters. */
+    ( void ) mode;
+
+    /* Initialize the queue list, if needed. */
+    prvInitializeQueueList();
+
+    /* Check queue name. */
+    if( prvValidateQueueName( name, &xNameLength ) == pdFALSE )
+    {
+        /* Invalid name. */
+        errno = EINVAL;
+        xMessageQueue = ( mqd_t ) -1;
+    }
+
+    /* Check attributes, if given. */
+    if( xMessageQueue == NULL )
+    {
+        if( ( oflag & O_CREAT ) && ( attr != NULL ) && ( ( attr->mq_maxmsg <= 0 ) || ( attr->mq_msgsize <= 0 ) ) )
+        {
+            /* Invalid mq_attr.mq_maxmsg or mq_attr.mq_msgsize. */
+            errno = EINVAL;
+            xMessageQueue = ( mqd_t ) -1;
+        }
+    }
+
+    if( xMessageQueue == NULL )
+    {
+        /* Lock the mutex that guards access to the queue list. This call will
+         * never fail because it blocks forever. */
+        ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );
+
+        /* Search the queue list to check if the queue exists. */
+        if( prvFindQueueInList( ( QueueListElement_t ** ) &xMessageQueue,
+                                name,
+                                ( mqd_t ) NULL ) == pdTRUE )
+        {
+            /* If the mq exists, check that this function wasn't called with
+             * O_CREAT and O_EXCL. */
+            if( ( oflag & O_EXCL ) && ( oflag & O_CREAT ) )
+            {
+                errno = EEXIST;
+                xMessageQueue = ( mqd_t ) -1;
+            }
+            else
+            {
+                /* Check if the mq has been unlinked and is pending removal. */
+                if( ( ( QueueListElement_t * ) xMessageQueue )->xPendingUnlink == pdTRUE )
+                {
+                    /* Queue pending deletion. Don't allow it to be re-opened. */
+                    errno = EINVAL;
+                    xMessageQueue = ( mqd_t ) -1;
+                }
+                else
+                {
+                    /* Increase count of open file descriptors for queue. */
+                    ( ( QueueListElement_t * ) xMessageQueue )->xOpenDescriptors++;
+                }
+            }
+        }
+        /* Queue does not exist. */
+        else
+        {
+            /* Only create the new queue if O_CREAT was specified. */
+            if( oflag & O_CREAT )
+            {
+                /* Copy attributes if provided. */
+                if( attr != NULL )
+                {
+                    xQueueCreationAttr = *attr;
+                }
+
+                /* Copy oflags. */
+                xQueueCreationAttr.mq_flags = ( long ) oflag;
+
+                /* Create the new message queue. */
+                if( prvCreateNewMessageQueue( ( QueueListElement_t ** ) &xMessageQueue,
+                                              &xQueueCreationAttr,
+                                              name,
+                                              xNameLength ) == pdFALSE )
+                {
+                    errno = ENOSPC;
+                    xMessageQueue = ( mqd_t ) -1;
+                }
+            }
+            else
+            {
+                errno = ENOENT;
+                xMessageQueue = ( mqd_t ) -1;
+            }
+        }
+
+        /* Release the mutex protecting the queue list. */
+        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
+    }
+
+    return xMessageQueue;
+}
+
+/*-----------------------------------------------------------*/
+
+ssize_t mq_receive( mqd_t mqdes,
+                    char * msg_ptr,
+                    size_t msg_len,
+                    unsigned int * msg_prio )
+{
+    return mq_timedreceive( mqdes, msg_ptr, msg_len, msg_prio, NULL );
+}
+
+/*-----------------------------------------------------------*/
+
+int mq_send( mqd_t mqdes,
+             const char * msg_ptr,
+             size_t msg_len,
+             unsigned msg_prio )
+{
+    return mq_timedsend( mqdes, msg_ptr, msg_len, msg_prio, NULL );
+}
+
+/*-----------------------------------------------------------*/
+
+ssize_t mq_timedreceive( mqd_t mqdes,
+                         char * msg_ptr,
+                         size_t msg_len,
+                         unsigned * msg_prio,
+                         const struct timespec * abstime )
+{
+    ssize_t xStatus = 0;
+    int iCalculateTimeoutReturn = 0;
+    TickType_t xTimeoutTicks = 0;
+    QueueListElement_t * pxMessageQueue = ( QueueListElement_t * ) mqdes;
+    QueueElement_t xReceiveData = { 0 };
+
+    /* Silence warnings about unused parameters. */
+    ( void ) msg_prio;
+
+    /* Lock the mutex that guards access to the queue list. This call will
+     * never fail because it blocks forever. */
+    ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );
+
+    /* Find the mq referenced by mqdes. */
+    if( prvFindQueueInList( NULL, NULL, mqdes ) == pdFALSE )
+    {
+        /* Queue not found; bad descriptor. */
+        errno = EBADF;
+        xStatus = -1;
+    }
+
+    /* Verify that msg_len is large enough. */
+    if( xStatus == 0 )
+    {
+        if( msg_len < ( size_t ) pxMessageQueue->xAttr.mq_msgsize )
+        {
+            /* msg_len too small. */
+            errno = EMSGSIZE;
+            xStatus = -1;
+        }
+    }
+
+    if( xStatus == 0 )
+    {
+        /* Convert abstime to a tick timeout. */
+        iCalculateTimeoutReturn = prvCalculateTickTimeout( pxMessageQueue->xAttr.mq_flags,
+                                                           abstime,
+                                                           &xTimeoutTicks );
+
+        if( iCalculateTimeoutReturn != 0 )
+        {
+            errno = iCalculateTimeoutReturn;
+            xStatus = -1;
+        }
+    }
+
+    /* Release the mutex protecting the queue list. */
+    ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
+
+    if( xStatus == 0 )
+    {
+        /* Receive data from the FreeRTOS queue. */
+        if( xQueueReceive( pxMessageQueue->xQueue,
+                           &xReceiveData,
+                           xTimeoutTicks ) == pdFALSE )
+        {
+            /* If queue receive fails, set the appropriate errno. */
+            if( pxMessageQueue->xAttr.mq_flags & O_NONBLOCK )
+            {
+                /* Set errno to EAGAIN for nonblocking mq. */
+                errno = EAGAIN;
+            }
+            else
+            {
+                /* Otherwise, set errno to ETIMEDOUT. */
+                errno = ETIMEDOUT;
+            }
+
+            xStatus = -1;
+        }
+    }
+
+    if( xStatus == 0 )
+    {
+        /* Get the length of data for return value. */
+        xStatus = ( ssize_t ) xReceiveData.xDataSize;
+
+        /* Copy received data into given buffer, then free it. */
+        ( void ) memcpy( msg_ptr, xReceiveData.pcData, xReceiveData.xDataSize );
+        vPortFree( xReceiveData.pcData );
+    }
+
+    return xStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int mq_timedsend( mqd_t mqdes,
+                  const char * msg_ptr,
+                  size_t msg_len,
+                  unsigned int msg_prio,
+                  const struct timespec * abstime )
+{
+    int iStatus = 0, iCalculateTimeoutReturn = 0;
+    TickType_t xTimeoutTicks = 0;
+    QueueListElement_t * pxMessageQueue = ( QueueListElement_t * ) mqdes;
+    QueueElement_t xSendData = { 0 };
+
+    /* Silence warnings about unused parameters. */
+    ( void ) msg_prio;
+
+    /* Lock the mutex that guards access to the queue list. This call will
+     * never fail because it blocks forever. */
+    ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );
+
+    /* Find the mq referenced by mqdes. */
+    if( prvFindQueueInList( NULL, NULL, mqdes ) == pdFALSE )
+    {
+        /* Queue not found; bad descriptor. */
+        errno = EBADF;
+        iStatus = -1;
+    }
+
+    /* Verify that mq_msgsize is large enough. */
+    if( iStatus == 0 )
+    {
+        if( msg_len > ( size_t ) pxMessageQueue->xAttr.mq_msgsize )
+        {
+            /* msg_len too large. */
+            errno = EMSGSIZE;
+            iStatus = -1;
+        }
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Convert abstime to a tick timeout. */
+        iCalculateTimeoutReturn = prvCalculateTickTimeout( pxMessageQueue->xAttr.mq_flags,
+                                                           abstime,
+                                                           &xTimeoutTicks );
+
+        if( iCalculateTimeoutReturn != 0 )
+        {
+            errno = iCalculateTimeoutReturn;
+            iStatus = -1;
+        }
+    }
+
+    /* Release the mutex protecting the queue list. */
+    ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
+
+    /* Allocate memory for the message. */
+    if( iStatus == 0 )
+    {
+        xSendData.xDataSize = msg_len;
+        xSendData.pcData = pvPortMalloc( msg_len );
+
+        /* Check that memory allocation succeeded. */
+        if( xSendData.pcData == NULL )
+        {
+            /* msg_len too large. */
+            errno = EMSGSIZE;
+            iStatus = -1;
+        }
+        else
+        {
+            /* Copy the data to send. */
+            ( void ) memcpy( xSendData.pcData, msg_ptr, msg_len );
+        }
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Send data to the FreeRTOS queue. */
+        if( xQueueSend( pxMessageQueue->xQueue,
+                        &xSendData,
+                        xTimeoutTicks ) == pdFALSE )
+        {
+            /* If queue send fails, set the appropriate errno. */
+            if( pxMessageQueue->xAttr.mq_flags & O_NONBLOCK )
+            {
+                /* Set errno to EAGAIN for nonblocking mq. */
+                errno = EAGAIN;
+            }
+            else
+            {
+                /* Otherwise, set errno to ETIMEDOUT. */
+                errno = ETIMEDOUT;
+            }
+
+            /* Free the allocated queue data. */
+            vPortFree( xSendData.pcData );
+
+            iStatus = -1;
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int mq_unlink( const char * name )
+{
+    int iStatus = 0;
+    size_t xNameSize = 0;
+    BaseType_t xQueueRemoved = pdFALSE;
+    QueueListElement_t * pxMessageQueue = NULL;
+
+    /* Initialize the queue list, if needed. */
+    prvInitializeQueueList();
+
+    /* Check queue name. */
+    if( prvValidateQueueName( name, &xNameSize ) == pdFALSE )
+    {
+        /* Error with mq name. */
+        errno = EINVAL;
+        iStatus = -1;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Lock the mutex that guards access to the queue list. This call will
+         * never fail because it blocks forever. */
+        ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );
+
+        /* Check if the named queue exists. */
+        if( prvFindQueueInList( &pxMessageQueue, name, ( mqd_t ) NULL ) == pdTRUE )
+        {
+            /* If the queue exists and there are no open descriptors to it,
+             * remove it from the list. */
+            if( pxMessageQueue->xOpenDescriptors == 0 )
+            {
+                listREMOVE( &pxMessageQueue->xLink );
+
+                /* Set the flag to delete the queue. Deleting the queue is deferred
+                 * until xQueueListMutex is released. */
+                xQueueRemoved = pdTRUE;
+            }
+            else
+            {
+                /* If the queue has open descriptors, set the pending unlink flag
+                 * so that mq_close will free its resources. */
+                pxMessageQueue->xPendingUnlink = pdTRUE;
+            }
+        }
+        else
+        {
+            /* The named message queue doesn't exist. */
+            errno = ENOENT;
+            iStatus = -1;
+        }
+
+        /* Release the mutex protecting the queue list. */
+        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
+    }
+
+    /* Delete all resources used by the queue if needed. */
+    if( xQueueRemoved == pdTRUE )
+    {
+        prvDeleteMessageQueue( pxMessageQueue );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread.c
new file mode 100755
index 0000000..f34e9ec
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread.c
@@ -0,0 +1,510 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_pthread.c
+ * @brief Implementation of thread functions in pthread.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+#include <string.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/pthread.h"
+
+/**
+ * @brief Thread attribute object.
+ */
+typedef struct pthread_attr_internal
+{
+    uint16_t usStackSize;                /**< Stack size. */
+    uint16_t usSchedPriorityDetachState; /**< Schedule priority 15 bits (LSB) Detach state: 1 bits (MSB) */
+} pthread_attr_internal_t;
+
+#define pthreadDETACH_STATE_MASK      0x8000
+#define pthreadSCHED_PRIORITY_MASK    0x7FFF
+#define pthreadDETACH_STATE_SHIFT     15
+#define pthreadGET_SCHED_PRIORITY( var )    ( ( var ) & ( pthreadSCHED_PRIORITY_MASK ) )
+#define pthreadIS_JOINABLE( var )           ( ( ( var ) & ( pthreadDETACH_STATE_MASK ) ) == pthreadDETACH_STATE_MASK )
+
+/**
+ * @brief Thread object.
+ */
+typedef struct pthread_internal
+{
+    pthread_attr_internal_t xAttr;        /**< Thread attributes. */
+    void * ( *pvStartRoutine )( void * ); /**< Application thread function. */
+    void * xTaskArg;                      /**< Arguments for application thread function. */
+    TaskHandle_t xTaskHandle;             /**< FreeRTOS task handle. */
+    StaticSemaphore_t xJoinBarrier;       /**< Synchronizes the two callers of pthread_join. */
+    StaticSemaphore_t xJoinMutex;         /**< Ensures that only one other thread may join this thread. */
+    void * xReturn;                       /**< Return value of pvStartRoutine. */
+} pthread_internal_t;
+
+/**
+ * @brief Terminates the calling thread.
+ *
+ * For joinable threads, this function waits for pthread_join. Otherwise,
+ * it deletes the thread and frees up resources used by the thread.
+ *
+ * @return This function does not return.
+ */
+static void prvExitThread( void );
+
+/**
+ * @brief Wrapper function for the user's thread routine.
+ *
+ * This function is executed as a FreeRTOS task function.
+ * @param[in] pxArg A pointer to a pthread_internal_t.
+ *
+ * @return nothing
+ */
+static void prvRunThread( void * pxArg );
+
+/**
+ * @brief Default pthread_attr_t.
+ */
+static const pthread_attr_internal_t xDefaultThreadAttributes =
+{
+    .usStackSize                = PTHREAD_STACK_MIN,
+    .usSchedPriorityDetachState = ( ( uint16_t ) tskIDLE_PRIORITY & pthreadSCHED_PRIORITY_MASK ) | ( PTHREAD_CREATE_JOINABLE << pthreadDETACH_STATE_SHIFT ),
+};
+
+/*-----------------------------------------------------------*/
+
+static void prvExitThread( void )
+{
+    pthread_internal_t * pxThread = ( pthread_internal_t * ) pthread_self();
+
+    /* If this thread is joinable, wait for a call to pthread_join. */
+    if( pthreadIS_JOINABLE( pxThread->xAttr.usSchedPriorityDetachState ) )
+    {
+        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxThread->xJoinBarrier );
+
+        /* Suspend until the call to pthread_join. The caller of pthread_join
+         * will perform cleanup. */
+        vTaskSuspend( NULL );
+    }
+    else
+    {
+        /* For a detached thread, perform cleanup of thread object. */
+        vPortFree( pxThread );
+        vTaskDelete( NULL );
+    }
+}
+
+/*-----------------------------------------------------------*/
+
+static void prvRunThread( void * pxArg )
+{
+    pthread_internal_t * pxThread = ( pthread_internal_t * ) pxArg;
+
+    /* Run the thread routine. */
+    pxThread->xReturn = pxThread->pvStartRoutine( ( void * ) pxThread->xTaskArg );
+
+    /* Exit once finished. This function does not return. */
+    prvExitThread();
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_destroy( pthread_attr_t * attr )
+{
+    ( void ) attr;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_getdetachstate( const pthread_attr_t * attr,
+                                 int * detachstate )
+{
+    pthread_attr_internal_t * pxAttr = ( pthread_attr_internal_t * ) ( attr );
+
+    if( pthreadIS_JOINABLE( pxAttr->usSchedPriorityDetachState ) )
+    {
+        *detachstate = PTHREAD_CREATE_JOINABLE;
+    }
+    else
+    {
+        *detachstate = PTHREAD_CREATE_DETACHED;
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_getschedparam( const pthread_attr_t * attr,
+                                struct sched_param * param )
+{
+    pthread_attr_internal_t * pxAttr = ( pthread_attr_internal_t * ) ( attr );
+
+    param->sched_priority = ( int ) ( pthreadGET_SCHED_PRIORITY( pxAttr->usSchedPriorityDetachState ) );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_getstacksize( const pthread_attr_t * attr,
+                               size_t * stacksize )
+{
+    pthread_attr_internal_t * pxAttr = ( pthread_attr_internal_t * ) ( attr );
+
+    *stacksize = ( size_t ) pxAttr->usStackSize;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_init( pthread_attr_t * attr )
+{
+    /* Copy the default values into the new thread attributes object. */
+    *( ( pthread_attr_internal_t * ) ( attr ) ) = xDefaultThreadAttributes;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_setdetachstate( pthread_attr_t * attr,
+                                 int detachstate )
+{
+    int iStatus = 0;
+    pthread_attr_internal_t * pxAttr = ( pthread_attr_internal_t * ) ( attr );
+
+    if( ( detachstate != PTHREAD_CREATE_DETACHED ) && ( detachstate != PTHREAD_CREATE_JOINABLE ) )
+    {
+        iStatus = EINVAL;
+    }
+    else
+    {
+        /* clear and then set msb bit to detachstate) */
+        pxAttr->usSchedPriorityDetachState &= ~pthreadDETACH_STATE_MASK;
+        pxAttr->usSchedPriorityDetachState |= ( ( uint16_t ) detachstate << pthreadDETACH_STATE_SHIFT );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_setschedparam( pthread_attr_t * attr,
+                                const struct sched_param * param )
+{
+    int iStatus = 0;
+    pthread_attr_internal_t * pxAttr = ( pthread_attr_internal_t * ) ( attr );
+
+    /* Check for NULL param. */
+    if( param == NULL )
+    {
+        iStatus = EINVAL;
+    }
+
+    /* Ensure that param.sched_priority is valid. */
+    if( ( iStatus == 0 ) &&
+        ( ( param->sched_priority > sched_get_priority_max( SCHED_OTHER ) ) ||
+          ( param->sched_priority < 0 ) ) )
+    {
+        iStatus = ENOTSUP;
+    }
+
+    /* Set the sched_param. */
+    if( iStatus == 0 )
+    {
+        /* clear and then set  15 LSB to schedule priority) */
+        pxAttr->usSchedPriorityDetachState &= ~pthreadSCHED_PRIORITY_MASK;
+        pxAttr->usSchedPriorityDetachState |= ( ( uint16_t ) param->sched_priority );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_setschedpolicy( pthread_attr_t * attr,
+                                 int policy )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) attr;
+    ( void ) policy;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_attr_setstacksize( pthread_attr_t * attr,
+                               size_t stacksize )
+{
+    int iStatus = 0;
+    pthread_attr_internal_t * pxAttr = ( pthread_attr_internal_t * ) ( attr );
+
+    if( stacksize < PTHREAD_STACK_MIN )
+    {
+        iStatus = EINVAL;
+    }
+    else
+    {
+        pxAttr->usStackSize = ( uint16_t ) stacksize;
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_create( pthread_t * thread,
+                    const pthread_attr_t * attr,
+                    void *( *startroutine )( void * ),
+                    void * arg )
+{
+    int iStatus = 0;
+    pthread_internal_t * pxThread = NULL;
+    struct sched_param xSchedParam = { .sched_priority = tskIDLE_PRIORITY };
+
+    /* Allocate memory for new thread object. */
+    pxThread = ( pthread_internal_t * ) pvPortMalloc( sizeof( pthread_internal_t ) );
+
+    if( pxThread == NULL )
+    {
+        /* No memory. */
+        iStatus = EAGAIN;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* No attributes given, use default attributes. */
+        if( attr == NULL )
+        {
+            pxThread->xAttr = xDefaultThreadAttributes;
+        }
+        /* Otherwise, use provided attributes. */
+        else
+        {
+            pxThread->xAttr = *( ( pthread_attr_internal_t * ) ( attr ) );
+        }
+
+        /* Get priority from attributes */
+        xSchedParam.sched_priority = ( int ) pthreadGET_SCHED_PRIORITY( pxThread->xAttr.usSchedPriorityDetachState );
+
+        /* Set argument and start routine. */
+        pxThread->xTaskArg = arg;
+        pxThread->pvStartRoutine = startroutine;
+
+        /* If this thread is joinable, create the synchronization mechanisms for
+         * pthread_join. */
+
+        if( pthreadIS_JOINABLE( pxThread->xAttr.usSchedPriorityDetachState ) )
+        {
+            /* These calls will not fail when their arguments aren't NULL. */
+            ( void ) xSemaphoreCreateMutexStatic( &pxThread->xJoinMutex );
+            ( void ) xSemaphoreCreateBinaryStatic( &pxThread->xJoinBarrier );
+        }
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Suspend all tasks to create a critical section. This ensures that
+         * the new thread doesn't exit before a tag is assigned. */
+        vTaskSuspendAll();
+
+        /* Create the FreeRTOS task that will run the pthread. */
+        if( xTaskCreate( prvRunThread,
+                         posixconfigPTHREAD_TASK_NAME,
+                         ( uint16_t ) ( pxThread->xAttr.usStackSize / sizeof( StackType_t ) ),
+                         ( void * ) pxThread,
+                         xSchedParam.sched_priority,
+                         &pxThread->xTaskHandle ) != pdPASS )
+        {
+            /* Task creation failed, no memory. */
+            vPortFree( pxThread );
+            iStatus = EAGAIN;
+        }
+        else
+        {
+            /* Store the pointer to the thread object in the task tag. */
+            vTaskSetApplicationTaskTag( pxThread->xTaskHandle, ( TaskHookFunction_t ) pxThread );
+
+            /* Set the thread object for the user. */
+            *thread = ( pthread_t ) pxThread;
+        }
+
+        /* End the critical section. */
+        xTaskResumeAll();
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_getschedparam( pthread_t thread,
+                           int * policy,
+                           struct sched_param * param )
+{
+    int iStatus = 0;
+    pthread_internal_t * pxThread = ( pthread_internal_t * ) thread;
+
+    *policy = SCHED_OTHER;
+    param->sched_priority = ( int ) pthreadGET_SCHED_PRIORITY( pxThread->xAttr.usSchedPriorityDetachState );
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_equal( pthread_t t1,
+                   pthread_t t2 )
+{
+    return t1 == t2;
+}
+
+/*-----------------------------------------------------------*/
+
+void pthread_exit( void * value_ptr )
+{
+    pthread_internal_t * pxThread = ( pthread_internal_t * ) pthread_self();
+
+    /* Set the return value. */
+    pxThread->xReturn = value_ptr;
+
+    /* Exit this thread. */
+    prvExitThread();
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_join( pthread_t pthread,
+                  void ** retval )
+{
+    int iStatus = 0;
+    pthread_internal_t * pxThread = ( pthread_internal_t * ) pthread;
+
+    /* Make sure pthread is joinable. Otherwise, this function would block
+     * forever waiting for an unjoinable thread. */
+    if( !pthreadIS_JOINABLE( pxThread->xAttr.usSchedPriorityDetachState ) )
+    {
+        iStatus = EDEADLK;
+    }
+
+    /* Only one thread may attempt to join another. Lock the join mutex
+     * to prevent other threads from calling pthread_join on the same thread. */
+    if( iStatus == 0 )
+    {
+        if( xSemaphoreTake( ( SemaphoreHandle_t ) &pxThread->xJoinMutex, 0 ) != pdPASS )
+        {
+            /* Another thread has already joined the requested thread, which would
+             * cause this thread to wait forever. */
+            iStatus = EDEADLK;
+        }
+    }
+
+    /* Attempting to join the calling thread would cause a deadlock. */
+    if( iStatus == 0 )
+    {
+        if( pthread_equal( pthread_self(), pthread ) != 0 )
+        {
+            iStatus = EDEADLK;
+        }
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Wait for the joining thread to finish. Because this call waits forever,
+         * it should never fail. */
+        ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &pxThread->xJoinBarrier, portMAX_DELAY );
+
+        /* Create a critical section to clean up the joined thread. */
+        vTaskSuspendAll();
+
+        /* Release xJoinBarrier and delete it. */
+        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxThread->xJoinBarrier );
+        vSemaphoreDelete( ( SemaphoreHandle_t ) &pxThread->xJoinBarrier );
+
+        /* Release xJoinMutex and delete it. */
+        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxThread->xJoinMutex );
+        vSemaphoreDelete( ( SemaphoreHandle_t ) &pxThread->xJoinMutex );
+
+        /* Delete the FreeRTOS task that ran the thread. */
+        vTaskDelete( pxThread->xTaskHandle );
+
+        /* Set the return value. */
+        if( retval != NULL )
+        {
+            *retval = pxThread->xReturn;
+        }
+
+        /* Free the thread object. */
+        vPortFree( pxThread );
+
+        /* End the critical section. */
+        xTaskResumeAll();
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+pthread_t pthread_self( void )
+{
+    /* Return a reference to this pthread object, which is stored in the
+     * FreeRTOS task tag. */
+    return ( pthread_t ) xTaskGetApplicationTaskTag( NULL );
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_setschedparam( pthread_t thread,
+                           int policy,
+                           const struct sched_param * param )
+{
+    int iStatus = 0;
+
+    pthread_internal_t * pxThread = ( pthread_internal_t * ) thread;
+
+    /* Silence compiler warnings about unused parameters. */
+    ( void ) policy;
+
+    /* Copy the given sched_param. */
+    iStatus = pthread_attr_setschedparam( ( pthread_attr_t * ) &pxThread->xAttr, param );
+
+    if( iStatus == 0 )
+    {
+        /* Change the priority of the FreeRTOS task. */
+        vTaskPrioritySet( pxThread->xTaskHandle, param->sched_priority );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_barrier.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_barrier.c
new file mode 100755
index 0000000..2b621cb
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_barrier.c
@@ -0,0 +1,167 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_pthread_barrier.c
+ * @brief Implementation of barrier functions in pthread.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/pthread.h"
+
+#include "atomic.h"
+
+/*
+ * @brief barrier max count
+ *
+ * Barriers are implemented on FreeRTOS event groups, of which 8 bits are usable
+ * when configUSE_16_BIT_TICKS is 1. Otherwise, 24 bits are usable.
+ */
+/**@{ */
+#if ( configUSE_16_BIT_TICKS == 1 )
+    #define posixPTHREAD_BARRIER_MAX_COUNT    ( 8 )
+#else
+    #define posixPTHREAD_BARRIER_MAX_COUNT    ( 24 )
+#endif
+/**@} */
+
+/*-----------------------------------------------------------*/
+
+int pthread_barrier_destroy( pthread_barrier_t * barrier )
+{
+    pthread_barrier_internal_t * pxBarrier = ( pthread_barrier_internal_t * ) ( barrier );
+
+    /* Free all resources used by the barrier. */
+    ( void ) vEventGroupDelete( ( EventGroupHandle_t ) &pxBarrier->xBarrierEventGroup );
+    ( void ) vSemaphoreDelete( ( SemaphoreHandle_t ) &pxBarrier->xThreadCountSemaphore );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_barrier_init( pthread_barrier_t * barrier,
+                          const pthread_barrierattr_t * attr,
+                          unsigned count )
+{
+    int iStatus = 0;
+    pthread_barrier_internal_t * pxNewBarrier = ( pthread_barrier_internal_t * ) ( barrier );
+
+    /* Silence warnings about unused parameters. */
+    ( void ) attr;
+
+    /* Ensure count is greater than 0. */
+    if( count == 0 )
+    {
+        iStatus = EINVAL;
+    }
+
+    /* Ensure that count will fit in a FreeRTOS event group. */
+    if( iStatus == 0 )
+    {
+        if( count > posixPTHREAD_BARRIER_MAX_COUNT )
+        {
+            /* No memory exists in the event group for more than
+             * posixPTHREAD_BARRIER_MAX_COUNT threads. */
+            iStatus = ENOMEM;
+        }
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Set the current thread count and threshold. */
+        pxNewBarrier->uThreadCount = 0;
+        pxNewBarrier->uThreshold = count;
+
+        /* Create the FreeRTOS event group. This call will not fail when its
+         * argument isn't NULL. */
+        ( void ) xEventGroupCreateStatic( &pxNewBarrier->xBarrierEventGroup );
+
+        /* Create the semaphore that prevents more than count threads from being
+         * unblocked by a single successful pthread_barrier_wait. This semaphore
+         * counts down from count and cannot decrement below 0. */
+        ( void ) xSemaphoreCreateCountingStatic( ( UBaseType_t ) count, /* Max count. */
+                                                 ( UBaseType_t ) count, /* Initial count. */
+                                                 &pxNewBarrier->xThreadCountSemaphore );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_barrier_wait( pthread_barrier_t * barrier )
+{
+    int iStatus = 0;
+    unsigned i = 0; /* Loop iterator. */
+    pthread_barrier_internal_t * pxBarrier = ( pthread_barrier_internal_t * ) ( barrier );
+    unsigned uThreadNumber = 0;
+
+    /* Decrement the number of threads waiting on this barrier. This will prevent more
+     * than pxBarrier->uThreshold threads from being unblocked by a single successful
+     * pthread_barrier_wait call.
+     *
+     * This call will never fail because it blocks forever.
+     */
+    ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &pxBarrier->xThreadCountSemaphore, portMAX_DELAY );
+
+    uThreadNumber = Atomic_Increment_u32( ( uint32_t * ) &pxBarrier->uThreadCount );
+
+    /* Set the bit in the event group representing this thread, then wait for the other
+     * threads to set their bit. This call should wait forever until all threads have set
+     * their bit, so the return value is ignored. */
+    ( void ) xEventGroupSync( ( EventGroupHandle_t ) &pxBarrier->xBarrierEventGroup,
+                              1 << uThreadNumber,                 /* Which bit in the event group to set. */
+                              ( 1 << pxBarrier->uThreshold ) - 1, /* Wait for all threads to set their bits. */
+                              portMAX_DELAY );
+
+    /* The first thread to enter the barrier gets PTHREAD_BARRIER_SERIAL_THREAD as its
+     * return value and resets xThreadCountSemaphore. */
+
+    if( uThreadNumber == 0 )
+    {
+        iStatus = PTHREAD_BARRIER_SERIAL_THREAD;
+
+        /* uThreadCount can be safely changed without locking xThreadCountMutex
+         * because xThreadCountSemaphore is currently 0. */
+        pxBarrier->uThreadCount = 0;
+
+        /* Reset xThreadCountSemaphore. This allows more threads to enter the
+         * barrier, starting a new cycle. */
+        for( i = 0; i < pxBarrier->uThreshold; i++ )
+        {
+            xSemaphoreGive( ( SemaphoreHandle_t ) &pxBarrier->xThreadCountSemaphore );
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_cond.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_cond.c
new file mode 100755
index 0000000..b972634
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_cond.c
@@ -0,0 +1,296 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_pthread_cond.c
+ * @brief Implementation of condition variable functions in pthread.h
+ */
+
+/* C standard library includes. */
+#include <limits.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/pthread.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+#include "atomic.h"
+
+/**
+ * @brief Initialize a PTHREAD_COND_INITIALIZER cond.
+ *
+ * PTHREAD_COND_INITIALIZER sets a flag for a cond to be initialized later.
+ * This function performs the initialization.
+ * @param[in] pxCond The cond to initialize.
+ *
+ * @return nothing
+ */
+static void prvInitializeStaticCond( pthread_cond_internal_t * pxCond );
+
+/*-----------------------------------------------------------*/
+
+static void prvInitializeStaticCond( pthread_cond_internal_t * pxCond )
+{
+    /* Check if the condition variable needs to be initialized. */
+    if( pxCond->xIsInitialized == pdFALSE )
+    {
+        /* Cond initialization must be in a critical section to prevent two threads
+         * from initializing it at the same time. */
+        taskENTER_CRITICAL();
+
+        /* Check again that the cond is still uninitialized, i.e. it wasn't
+         * initialized while this function was waiting to enter the critical
+         * section. */
+        if( pxCond->xIsInitialized == pdFALSE )
+        {
+            /* Set the members of the cond. The semaphore create calls will never fail
+             * when their arguments aren't NULL. */
+            pxCond->xIsInitialized = pdTRUE;
+            ( void ) xSemaphoreCreateCountingStatic( INT_MAX, 0U, &pxCond->xCondWaitSemaphore );
+            pxCond->iWaitingThreads = 0;
+        }
+
+        /* Exit the critical section. */
+        taskEXIT_CRITICAL();
+    }
+}
+
+/**
+ * @brief Check "atomically" if iLocalWaitingThreads == pxCond->iWaitingThreads and decrement.
+ */
+static void prvTestAndDecrement( pthread_cond_t * pxCond,
+                                 unsigned iLocalWaitingThreads )
+{
+    /* Test local copy of threads waiting is larger than zero. */
+    while( iLocalWaitingThreads > 0 )
+    {
+        /* Test-and-set. Atomically check whether the copy in memory has changed.
+         * And, if not decrease the copy of threads waiting in memory. */
+        if( ATOMIC_COMPARE_AND_SWAP_SUCCESS == Atomic_CompareAndSwap_u32( ( uint32_t * ) &pxCond->iWaitingThreads, ( uint32_t ) iLocalWaitingThreads - 1, ( uint32_t ) iLocalWaitingThreads ) )
+        {
+            /* Signal one succeeded. Break. */
+            break;
+        }
+
+        /* Local copy may be out dated. Reload, and retry. */
+        iLocalWaitingThreads = pxCond->iWaitingThreads;
+    }
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_cond_broadcast( pthread_cond_t * cond )
+{
+    unsigned i = 0;
+    pthread_cond_internal_t * pxCond = ( pthread_cond_internal_t * ) ( cond );
+
+    /* If the cond is uninitialized, perform initialization. */
+    prvInitializeStaticCond( pxCond );
+
+    /* Local copy of number of threads waiting. */
+    unsigned iLocalWaitingThreads = pxCond->iWaitingThreads;
+
+    /* Test local copy of threads waiting is larger than zero. */
+    while( iLocalWaitingThreads > 0 )
+    {
+        /* Test-and-set. Atomically check whether the copy in memory has changed.
+         * And, if not set the copy of threads waiting in memory to zero. */
+        if( ATOMIC_COMPARE_AND_SWAP_SUCCESS == Atomic_CompareAndSwap_u32( ( uint32_t * ) &pxCond->iWaitingThreads, 0, ( uint32_t ) iLocalWaitingThreads ) )
+        {
+            /* Unblock all. */
+            for( i = 0; i < iLocalWaitingThreads; i++ )
+            {
+                ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxCond->xCondWaitSemaphore );
+            }
+
+            break;
+        }
+
+        /* Local copy is out dated. Reload, and retry. */
+        iLocalWaitingThreads = pxCond->iWaitingThreads;
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_cond_destroy( pthread_cond_t * cond )
+{
+    pthread_cond_internal_t * pxCond = ( pthread_cond_internal_t * ) ( cond );
+
+    /* Free all resources in use by the cond. */
+    vSemaphoreDelete( ( SemaphoreHandle_t ) &pxCond->xCondWaitSemaphore );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_cond_init( pthread_cond_t * cond,
+                       const pthread_condattr_t * attr )
+{
+    int iStatus = 0;
+    pthread_cond_internal_t * pxCond = ( pthread_cond_internal_t * ) cond;
+
+    /* Silence warnings about unused parameters. */
+    ( void ) attr;
+
+    if( pxCond == NULL )
+    {
+        iStatus = ENOMEM;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Set the members of the cond. The semaphore create calls will never fail
+         * when their arguments aren't NULL. */
+        pxCond->xIsInitialized = pdTRUE;
+
+        ( void ) xSemaphoreCreateCountingStatic( INT_MAX, 0U, &pxCond->xCondWaitSemaphore );
+        pxCond->iWaitingThreads = 0;
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_cond_signal( pthread_cond_t * cond )
+{
+    pthread_cond_internal_t * pxCond = ( pthread_cond_internal_t * ) ( cond );
+
+    /* If the cond is uninitialized, perform initialization. */
+    prvInitializeStaticCond( pxCond );
+
+    /* Local copy of number of threads waiting. */
+    unsigned iLocalWaitingThreads = pxCond->iWaitingThreads;
+
+    /* Test local copy of threads waiting is larger than zero. */
+    while( iLocalWaitingThreads > 0 )
+    {
+        /* Test-and-set. Atomically check whether the copy in memory has changed.
+         * And, if not decrease the copy of threads waiting in memory. */
+        if( ATOMIC_COMPARE_AND_SWAP_SUCCESS == Atomic_CompareAndSwap_u32( ( uint32_t * ) &pxCond->iWaitingThreads, ( uint32_t ) iLocalWaitingThreads - 1, ( uint32_t ) iLocalWaitingThreads ) )
+        {
+            /* Unblock one. */
+            ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxCond->xCondWaitSemaphore );
+
+            /* Signal one succeeded. Break. */
+            break;
+        }
+
+        /* Local copy may be out dated. Reload, and retry. */
+        iLocalWaitingThreads = pxCond->iWaitingThreads;
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_cond_timedwait( pthread_cond_t * cond,
+                            pthread_mutex_t * mutex,
+                            const struct timespec * abstime )
+{
+    unsigned iLocalWaitingThreads;
+    int iStatus = 0;
+    pthread_cond_internal_t * pxCond = ( pthread_cond_internal_t * ) ( cond );
+    TickType_t xDelay = portMAX_DELAY;
+
+    /* If the cond is uninitialized, perform initialization. */
+    prvInitializeStaticCond( pxCond );
+
+    /* Convert abstime to a delay in TickType_t if provided. */
+    if( abstime != NULL )
+    {
+        struct timespec xCurrentTime = { 0 };
+
+        /* Get current time */
+        if( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 )
+        {
+            iStatus = EINVAL;
+        }
+        else
+        {
+            iStatus = UTILS_AbsoluteTimespecToDeltaTicks( abstime, &xCurrentTime, &xDelay );
+        }
+    }
+
+    /* Increase the counter of threads blocking on condition variable, then
+     * unlock mutex. */
+    if( iStatus == 0 )
+    {
+        /* Atomically increments thread waiting by 1, and
+         * stores number of threads waiting before increment. */
+        iLocalWaitingThreads = Atomic_Increment_u32( ( uint32_t * ) &pxCond->iWaitingThreads );
+
+        iStatus = pthread_mutex_unlock( mutex );
+    }
+
+    /* Wait on the condition variable. */
+    if( iStatus == 0 )
+    {
+        if( xSemaphoreTake( ( SemaphoreHandle_t ) &pxCond->xCondWaitSemaphore,
+                            xDelay ) == pdPASS )
+        {
+            /* When successful, relock mutex. */
+            iStatus = pthread_mutex_lock( mutex );
+        }
+        else
+        {
+            /* Timeout. Relock mutex and decrement number of waiting threads. */
+            iStatus = ETIMEDOUT;
+            ( void ) pthread_mutex_lock( mutex );
+
+            /* Atomically decrements thread waiting by 1.
+             * If iLocalWaitingThreads is updated by other thread(s) in between,
+             * this implementation guarantees to decrement by 1 based on the
+             * value currently in pxCond->iWaitingThreads. */
+            prvTestAndDecrement( pxCond, iLocalWaitingThreads + 1 );
+        }
+    }
+    else
+    {
+        /* Atomically decrements thread waiting by 1.
+         * If iLocalWaitingThreads is updated by other thread(s) in between,
+         * this implementation guarantees to decrement by 1 based on the
+         * value currently in pxCond->iWaitingThreads. */
+        prvTestAndDecrement( pxCond, iLocalWaitingThreads + 1 );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_cond_wait( pthread_cond_t * cond,
+                       pthread_mutex_t * mutex )
+{
+    return pthread_cond_timedwait( cond, mutex, NULL );
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_mutex.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_mutex.c
new file mode 100755
index 0000000..0ea3aeb
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_pthread_mutex.c
@@ -0,0 +1,373 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_pthread_mutex.c
+ * @brief Implementation of mutex functions in pthread.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+#include <string.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/pthread.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+/**
+ * @brief Initialize a PTHREAD_MUTEX_INITIALIZER mutex.
+ *
+ * PTHREAD_MUTEX_INITIALIZER sets a flag for a mutex to be initialized later.
+ * This function performs the initialization.
+ * @param[in] pxMutex The mutex to initialize.
+ *
+ * @return nothing
+ */
+static void prvInitializeStaticMutex( pthread_mutex_internal_t * pxMutex );
+
+/**
+ * @brief Default pthread_mutexattr_t.
+ */
+static const pthread_mutexattr_internal_t xDefaultMutexAttributes =
+{
+    .iType = PTHREAD_MUTEX_DEFAULT,
+};
+
+/*-----------------------------------------------------------*/
+
+static void prvInitializeStaticMutex( pthread_mutex_internal_t * pxMutex )
+{
+    /* Check if the mutex needs to be initialized. */
+    if( pxMutex->xIsInitialized == pdFALSE )
+    {
+        /* Mutex initialization must be in a critical section to prevent two threads
+         * from initializing it at the same time. */
+        taskENTER_CRITICAL();
+
+        /* Check again that the mutex is still uninitialized, i.e. it wasn't
+         * initialized while this function was waiting to enter the critical
+         * section. */
+        if( pxMutex->xIsInitialized == pdFALSE )
+        {
+            /* Set the mutex as the default type. */
+            pxMutex->xAttr.iType = PTHREAD_MUTEX_DEFAULT;
+
+            /* Call the correct FreeRTOS mutex initialization function based on
+             * the mutex type. */
+            #if PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_RECURSIVE
+                ( void ) xSemaphoreCreateRecursiveMutexStatic( &pxMutex->xMutex );
+            #else
+                ( void ) xSemaphoreCreateMutexStatic( &pxMutex->xMutex );
+            #endif
+
+            pxMutex->xIsInitialized = pdTRUE;
+        }
+
+        /* Exit the critical section. */
+        taskEXIT_CRITICAL();
+    }
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutex_destroy( pthread_mutex_t * mutex )
+{
+    pthread_mutex_internal_t * pxMutex = ( pthread_mutex_internal_t * ) ( mutex );
+
+    /* Free resources in use by the mutex. */
+    if( pxMutex->xTaskOwner == NULL )
+    {
+        vSemaphoreDelete( ( SemaphoreHandle_t ) &pxMutex->xMutex );
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutex_init( pthread_mutex_t * mutex,
+                        const pthread_mutexattr_t * attr )
+{
+    int iStatus = 0;
+    pthread_mutex_internal_t * pxMutex = ( pthread_mutex_internal_t * ) mutex;
+
+    if( pxMutex == NULL )
+    {
+        /* No memory. */
+        iStatus = ENOMEM;
+    }
+
+    if( iStatus == 0 )
+    {
+        *pxMutex = FREERTOS_POSIX_MUTEX_INITIALIZER;
+
+        /* No attributes given, use default attributes. */
+        if( attr == NULL )
+        {
+            pxMutex->xAttr = xDefaultMutexAttributes;
+        }
+        /* Otherwise, use provided attributes. */
+        else
+        {
+            pxMutex->xAttr = *( ( pthread_mutexattr_internal_t * ) ( attr ) );
+        }
+
+        /* Call the correct FreeRTOS mutex creation function based on mutex type. */
+        if( pxMutex->xAttr.iType == PTHREAD_MUTEX_RECURSIVE )
+        {
+            /* Recursive mutex. */
+            ( void ) xSemaphoreCreateRecursiveMutexStatic( &pxMutex->xMutex );
+        }
+        else
+        {
+            /* All other mutex types. */
+            ( void ) xSemaphoreCreateMutexStatic( &pxMutex->xMutex );
+        }
+
+        /* Ensure that the FreeRTOS mutex was successfully created. */
+        if( ( SemaphoreHandle_t ) &pxMutex->xMutex == NULL )
+        {
+            /* Failed to create mutex. Set error EAGAIN and free mutex object. */
+            iStatus = EAGAIN;
+            vPortFree( pxMutex );
+        }
+        else
+        {
+            /* Mutex successfully created. */
+            pxMutex->xIsInitialized = pdTRUE;
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutex_lock( pthread_mutex_t * mutex )
+{
+    return pthread_mutex_timedlock( mutex, NULL );
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutex_timedlock( pthread_mutex_t * mutex,
+                             const struct timespec * abstime )
+{
+    int iStatus = 0;
+    pthread_mutex_internal_t * pxMutex = ( pthread_mutex_internal_t * ) ( mutex );
+    TickType_t xDelay = portMAX_DELAY;
+    BaseType_t xFreeRTOSMutexTakeStatus = pdFALSE;
+
+    /* If mutex in uninitialized, perform initialization. */
+    prvInitializeStaticMutex( pxMutex );
+
+    /* At this point, the mutex should be initialized. */
+    configASSERT( pxMutex->xIsInitialized == pdTRUE );
+
+    /* Convert abstime to a delay in TickType_t if provided. */
+    if( abstime != NULL )
+    {
+        struct timespec xCurrentTime = { 0 };
+
+        /* Get current time */
+        if( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 )
+        {
+            iStatus = EINVAL;
+        }
+        else
+        {
+            iStatus = UTILS_AbsoluteTimespecToDeltaTicks( abstime, &xCurrentTime, &xDelay );
+        }
+
+        /* If abstime was in the past, still attempt to lock the mutex without
+         * blocking, per POSIX spec. */
+        if( iStatus == ETIMEDOUT )
+        {
+            xDelay = 0;
+            iStatus = 0;
+        }
+    }
+
+    /* Check if trying to lock a currently owned mutex. */
+    if( ( iStatus == 0 ) &&
+        ( pxMutex->xAttr.iType == PTHREAD_MUTEX_ERRORCHECK ) &&  /* Only PTHREAD_MUTEX_ERRORCHECK type detects deadlock. */
+        ( pxMutex->xTaskOwner == xTaskGetCurrentTaskHandle() ) ) /* Check if locking a currently owned mutex. */
+    {
+        iStatus = EDEADLK;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Call the correct FreeRTOS mutex take function based on mutex type. */
+        if( pxMutex->xAttr.iType == PTHREAD_MUTEX_RECURSIVE )
+        {
+            xFreeRTOSMutexTakeStatus = xSemaphoreTakeRecursive( ( SemaphoreHandle_t ) &pxMutex->xMutex, xDelay );
+        }
+        else
+        {
+            xFreeRTOSMutexTakeStatus = xSemaphoreTake( ( SemaphoreHandle_t ) &pxMutex->xMutex, xDelay );
+        }
+
+        /* If the mutex was successfully taken, set its owner. */
+        if( xFreeRTOSMutexTakeStatus == pdPASS )
+        {
+            pxMutex->xTaskOwner = xTaskGetCurrentTaskHandle();
+        }
+        /* Otherwise, the mutex take timed out. */
+        else
+        {
+            iStatus = ETIMEDOUT;
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutex_trylock( pthread_mutex_t * mutex )
+{
+    int iStatus = 0;
+    struct timespec xTimeout =
+    {
+        .tv_sec  = 0,
+        .tv_nsec = 0
+    };
+
+    /* Attempt to lock with no timeout. */
+    iStatus = pthread_mutex_timedlock( mutex, &xTimeout );
+
+    /* POSIX specifies that this function should return EBUSY instead of
+     * ETIMEDOUT for attempting to lock a locked mutex. */
+    if( iStatus == ETIMEDOUT )
+    {
+        iStatus = EBUSY;
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutex_unlock( pthread_mutex_t * mutex )
+{
+    int iStatus = 0;
+    pthread_mutex_internal_t * pxMutex = ( pthread_mutex_internal_t * ) ( mutex );
+
+    /* If mutex in uninitialized, perform initialization. */
+    prvInitializeStaticMutex( pxMutex );
+
+    /* Check if trying to unlock an unowned mutex. */
+    if( ( ( pxMutex->xAttr.iType == PTHREAD_MUTEX_ERRORCHECK ) ||
+          ( pxMutex->xAttr.iType == PTHREAD_MUTEX_RECURSIVE ) ) &&
+        ( pxMutex->xTaskOwner != xTaskGetCurrentTaskHandle() ) )
+    {
+        iStatus = EPERM;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Suspend the scheduler so that
+         * mutex is unlocked AND owner is updated atomically */
+        vTaskSuspendAll();
+
+        /* Call the correct FreeRTOS mutex unlock function based on mutex type. */
+        if( pxMutex->xAttr.iType == PTHREAD_MUTEX_RECURSIVE )
+        {
+            ( void ) xSemaphoreGiveRecursive( ( SemaphoreHandle_t ) &pxMutex->xMutex );
+        }
+        else
+        {
+            ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxMutex->xMutex );
+        }
+
+        /* Update the owner of the mutex. A recursive mutex may still have an
+         * owner, so it should be updated with xSemaphoreGetMutexHolder. */
+        pxMutex->xTaskOwner = xSemaphoreGetMutexHolder( ( SemaphoreHandle_t ) &pxMutex->xMutex );
+
+        /* Resume the scheduler */
+        ( void ) xTaskResumeAll();
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutexattr_destroy( pthread_mutexattr_t * attr )
+{
+    ( void ) attr;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutexattr_gettype( const pthread_mutexattr_t * attr,
+                               int * type )
+{
+    pthread_mutexattr_internal_t * pxAttr = ( pthread_mutexattr_internal_t * ) ( attr );
+
+    *type = pxAttr->iType;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutexattr_init( pthread_mutexattr_t * attr )
+{
+    *( ( pthread_mutexattr_internal_t * ) ( attr ) ) = xDefaultMutexAttributes;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int pthread_mutexattr_settype( pthread_mutexattr_t * attr,
+                               int type )
+{
+    int iStatus = 0;
+    pthread_mutexattr_internal_t * pxAttr = ( pthread_mutexattr_internal_t * ) ( attr );
+
+    switch( type )
+    {
+        case PTHREAD_MUTEX_NORMAL:
+        case PTHREAD_MUTEX_RECURSIVE:
+        case PTHREAD_MUTEX_ERRORCHECK:
+            pxAttr->iType = type;
+            break;
+
+        default:
+            iStatus = EINVAL;
+            break;
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_sched.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_sched.c
new file mode 100755
index 0000000..7916a99
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_sched.c
@@ -0,0 +1,64 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_sched.c
+ * @brief Implementation of scheduler functions in sched.h
+ */
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/sched.h"
+
+/*-----------------------------------------------------------*/
+
+int sched_get_priority_max( int policy )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) policy;
+
+    return configMAX_PRIORITIES - 1;
+}
+
+/*-----------------------------------------------------------*/
+
+int sched_get_priority_min( int policy )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) policy;
+
+    return tskIDLE_PRIORITY;
+}
+
+/*-----------------------------------------------------------*/
+
+int sched_yield( void )
+{
+    taskYIELD();
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_semaphore.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_semaphore.c
new file mode 100755
index 0000000..6a83150
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_semaphore.c
@@ -0,0 +1,232 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_semaphore.c
+ * @brief Implementation of functions in semaphore.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/semaphore.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+#include "atomic.h"
+
+
+/*-----------------------------------------------------------*/
+
+int sem_destroy( sem_t * sem )
+{
+    sem_internal_t * pxSem = ( sem_internal_t * ) ( sem );
+
+    /* Free the resources in use by the semaphore. */
+    vSemaphoreDelete( ( SemaphoreHandle_t ) &pxSem->xSemaphore );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int sem_getvalue( sem_t * sem,
+                  int * sval )
+{
+    sem_internal_t * pxSem = ( sem_internal_t * ) ( sem );
+
+    /* Get value does not need atomic operation, since -- Open Group
+     * states "the updated value represents an actual semaphore value that
+     * occurred at some unspecified time during the call, but it need not be the
+     * actual value of the semaphore when it is returned to the calling process."
+     */
+    *sval = pxSem->value;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int sem_init( sem_t * sem,
+              int pshared,
+              unsigned value )
+{
+    int iStatus = 0;
+    sem_internal_t * pxSem = ( sem_internal_t * ) ( sem );
+
+    /* Silence warnings about unused parameters. */
+    ( void ) pshared;
+
+    /* Check value parameter. */
+    if( value > SEM_VALUE_MAX )
+    {
+        errno = EINVAL;
+        iStatus = -1;
+    }
+
+    /* value is guaranteed to not exceed INT32_MAX, which is the default value of SEM_VALUE_MAX (0x7FFFU). */
+    pxSem->value = ( int ) value;
+
+    /* Create the FreeRTOS semaphore.
+     * This is only used to queue threads when no semaphore is available.
+     * Initializing with semaphore initial count zero.
+     * This call will not fail because the memory for the semaphore has already been allocated.
+     */
+    if( iStatus == 0 )
+    {
+        ( void ) xSemaphoreCreateCountingStatic( SEM_VALUE_MAX, 0, &pxSem->xSemaphore );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int sem_post( sem_t * sem )
+{
+    sem_internal_t * pxSem = ( sem_internal_t * ) ( sem );
+
+    int iPreviouValue = Atomic_Increment_u32( ( uint32_t * ) &pxSem->value );
+
+    /* If previous semaphore value is equal or larger than zero, there is no
+     * thread waiting for this semaphore. Otherwise (<0), call FreeRTOS interface
+     * to wake up a thread. */
+    if( iPreviouValue < 0 )
+    {
+        /* Give the semaphore using the FreeRTOS API. */
+        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &pxSem->xSemaphore );
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int sem_timedwait( sem_t * sem,
+                   const struct timespec * abstime )
+{
+    int iStatus = 0;
+    sem_internal_t * pxSem = ( sem_internal_t * ) ( sem );
+    TickType_t xDelay = portMAX_DELAY;
+    int iPreviousValue = Atomic_Decrement_u32( ( uint32_t * ) &pxSem->value );
+
+    if( abstime != NULL )
+    {
+        /* If the provided timespec is invalid, still attempt to take the
+         * semaphore without blocking, per POSIX spec. */
+        if( UTILS_ValidateTimespec( abstime ) == false )
+        {
+            xDelay = 0;
+            iStatus = EINVAL;
+        }
+        else
+        {
+            struct timespec xCurrentTime = { 0 };
+
+            /* Get current time */
+            if( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 )
+            {
+                iStatus = EINVAL;
+            }
+            else
+            {
+                iStatus = UTILS_AbsoluteTimespecToDeltaTicks( abstime, &xCurrentTime, &xDelay );
+            }
+
+            /* If abstime was in the past, still attempt to take the semaphore without
+             * blocking, per POSIX spec. */
+            if( iStatus == ETIMEDOUT )
+            {
+                xDelay = 0;
+            }
+        }
+    }
+
+    /* If previous semaphore value is larger than zero, the thread entering this function call
+     * can take the semaphore without yielding. Else (<=0), calling into FreeRTOS API to yield.
+     */
+    if( iPreviousValue > 0 )
+    {
+        /* Under no circumstance shall the function fail with a timeout if the semaphore can be locked immediately. */
+        iStatus = 0;
+    }
+    else
+    {
+        /* Take the semaphore using the FreeRTOS API. */
+        if( xSemaphoreTake( ( SemaphoreHandle_t ) &pxSem->xSemaphore,
+                            xDelay ) != pdTRUE )
+        {
+            if( iStatus == 0 )
+            {
+                errno = ETIMEDOUT;
+            }
+            else
+            {
+                errno = iStatus;
+            }
+
+            iStatus = -1;
+        }
+        else
+        {
+            iStatus = 0;
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int sem_trywait( sem_t * sem )
+{
+    int iStatus = 0;
+
+    /* Setting an absolute timeout of 0 (i.e. in the past) will cause sem_timedwait
+     * to not block. */
+    struct timespec xTimeout = { 0 };
+
+    iStatus = sem_timedwait( sem, &xTimeout );
+
+    /* POSIX specifies that this function should set errno to EAGAIN and not
+     * ETIMEDOUT. */
+    if( ( iStatus == -1 ) && ( errno == ETIMEDOUT ) )
+    {
+        errno = EAGAIN;
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int sem_wait( sem_t * sem )
+{
+    return sem_timedwait( sem, NULL );
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_timer.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_timer.c
new file mode 100755
index 0000000..f790e83
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_timer.c
@@ -0,0 +1,330 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_timer.c
+ * @brief Implementation of timer functions in time.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/pthread.h"
+#include "FreeRTOS_POSIX/signal.h"
+#include "FreeRTOS_POSIX/time.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+/* FreeRTOS timer include. */
+#include "timers.h"
+
+/* Timespec zero check macros. */
+#define TIMESPEC_IS_ZERO( xTimespec )        ( xTimespec.tv_sec == 0 && xTimespec.tv_nsec == 0 ) /**< Check for 0. */
+#define TIMESPEC_IS_NOT_ZERO( xTimespec )    ( !( TIMESPEC_IS_ZERO( xTimespec ) ) )              /**< Check for not 0. */
+
+/**
+ * @brief Internal timer structure.
+ */
+typedef struct timer_internal
+{
+    StaticTimer_t xTimerBuffer;  /**< Memory that holds the FreeRTOS timer. */
+    struct sigevent xTimerEvent; /**< What to do when this timer expires. */
+    TickType_t xTimerPeriod;     /**< Period of this timer. */
+} timer_internal_t;
+
+/*-----------------------------------------------------------*/
+
+void prvTimerCallback( TimerHandle_t xTimerHandle )
+{
+    timer_internal_t * pxTimer = ( timer_internal_t * ) pvTimerGetTimerID( xTimerHandle );
+    pthread_t xTimerNotificationThread;
+
+    /* The value of the timer ID, set in timer_create, should not be NULL. */
+    configASSERT( pxTimer != NULL );
+
+    /* A value of SIGEV_SIGNAL isn't supported and should not have been successfully
+     * set. */
+    configASSERT( pxTimer->xTimerEvent.sigev_notify != SIGEV_SIGNAL );
+
+    /* Update the timer period, which may need to be set to an it_interval
+     * argument. This call should not block. */
+    if( pxTimer->xTimerPeriod > 0 )
+    {
+        xTimerChangePeriod( xTimerHandle, pxTimer->xTimerPeriod, 0 );
+    }
+
+    /* Create the timer notification thread if requested. */
+    if( pxTimer->xTimerEvent.sigev_notify == SIGEV_THREAD )
+    {
+        /* if the user has provided thread attributes, create a thread
+         * with the provided attributes. Otherwise dispatch callback directly */
+        if( pxTimer->xTimerEvent.sigev_notify_attributes == NULL )
+        {
+            ( *pxTimer->xTimerEvent.sigev_notify_function )( pxTimer->xTimerEvent.sigev_value );
+        }
+        else
+        {
+            ( void ) pthread_create( &xTimerNotificationThread,
+                                     pxTimer->xTimerEvent.sigev_notify_attributes,
+                                     ( void * ( * )( void * ) )pxTimer->xTimerEvent.sigev_notify_function,
+                                     pxTimer->xTimerEvent.sigev_value.sival_ptr );
+        }
+    }
+}
+
+/*-----------------------------------------------------------*/
+
+int timer_create( clockid_t clockid,
+                  struct sigevent * evp,
+                  timer_t * timerid )
+{
+    int iStatus = 0;
+    timer_internal_t * pxTimer = NULL;
+
+    /* Silence warnings about unused parameters. */
+    ( void ) clockid;
+
+    /* POSIX specifies that when evp is NULL, the behavior shall be as is
+     * sigev_notify is SIGEV_SIGNAL. SIGEV_SIGNAL is currently not supported. */
+    if( ( evp == NULL ) || ( evp->sigev_notify == SIGEV_SIGNAL ) )
+    {
+        errno = ENOTSUP;
+        iStatus = -1;
+    }
+
+    /* Allocate memory for a new timer object. */
+    if( iStatus == 0 )
+    {
+        pxTimer = pvPortMalloc( sizeof( timer_internal_t ) );
+
+        if( pxTimer == NULL )
+        {
+            errno = EAGAIN;
+            iStatus = -1;
+        }
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Copy the event notification structure and set the current timer period. */
+        pxTimer->xTimerEvent = *evp;
+        pxTimer->xTimerPeriod = 0;
+
+        /* Create a new FreeRTOS timer. This call will not fail because the
+         * memory for it has already been allocated, so the output parameter is
+         * also set. */
+        *timerid = ( timer_t ) xTimerCreateStatic( posixconfigTIMER_NAME,    /* Timer name. */
+                                                   portMAX_DELAY,            /* Initial timer period. Timers are created disarmed. */
+                                                   pdFALSE,                  /* Don't auto-reload timer. */
+                                                   ( void * ) pxTimer,       /* Timer id. */
+                                                   prvTimerCallback,         /* Timer expiration callback. */
+                                                   &pxTimer->xTimerBuffer ); /* Pre-allocated memory for timer. */
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int timer_delete( timer_t timerid )
+{
+    TimerHandle_t xTimerHandle = timerid;
+    timer_internal_t * pxTimer = ( timer_internal_t * ) pvTimerGetTimerID( xTimerHandle );
+
+    /* The value of the timer ID, set in timer_create, should not be NULL. */
+    configASSERT( pxTimer != NULL );
+
+    /* Stop the FreeRTOS timer. Because the timer is statically allocated, no call
+     * to xTimerDelete is necessary. The timer is stopped so that it's not referenced
+     * anywhere. xTimerStop will not fail when it has unlimited block time. */
+    ( void ) xTimerStop( xTimerHandle, portMAX_DELAY );
+
+    /* Wait until the timer stop command is processed. */
+    while( xTimerIsTimerActive( xTimerHandle ) == pdTRUE )
+    {
+        vTaskDelay( 1 );
+    }
+
+    /* Free the memory in use by the timer. */
+    vPortFree( pxTimer );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int timer_getoverrun( timer_t timerid )
+{
+    /* Silence warnings about unused parameters. */
+    ( void ) timerid;
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int timer_settime( timer_t timerid,
+                   int flags,
+                   const struct itimerspec * value,
+                   struct itimerspec * ovalue )
+{
+    int iStatus = 0;
+    TimerHandle_t xTimerHandle = timerid;
+    timer_internal_t * pxTimer = ( timer_internal_t * ) pvTimerGetTimerID( xTimerHandle );
+    TickType_t xNextTimerExpiration = 0, xTimerExpirationPeriod = 0;
+
+    /* Validate the value argument, but only if the timer isn't being disarmed. */
+    if( TIMESPEC_IS_NOT_ZERO( value->it_value ) )
+    {
+        if( ( UTILS_ValidateTimespec( &value->it_interval ) == false ) ||
+            ( UTILS_ValidateTimespec( &value->it_value ) == false ) )
+        {
+            errno = EINVAL;
+            iStatus = -1;
+        }
+    }
+
+    /* Set ovalue, if given. */
+    if( ovalue != NULL )
+    {
+        ( void ) timer_gettime( timerid, ovalue );
+    }
+
+    /* Stop the timer if it's currently active. */
+    if( ( iStatus == 0 ) && xTimerIsTimerActive( xTimerHandle ) )
+    {
+        ( void ) xTimerStop( xTimerHandle, portMAX_DELAY );
+    }
+
+    /* Only restart the timer if it_value is not zero. */
+    if( ( iStatus == 0 ) && TIMESPEC_IS_NOT_ZERO( value->it_value ) )
+    {
+        /* Convert it_interval to ticks, but only if it_interval is not 0. If
+         * it_interval is 0, then the timer is not periodic. */
+        if( TIMESPEC_IS_NOT_ZERO( value->it_interval ) )
+        {
+            ( void ) UTILS_TimespecToTicks( &value->it_interval, &xTimerExpirationPeriod );
+        }
+
+        /* Set the new timer period. A non-periodic timer will have its period set
+         * to portMAX_DELAY. */
+        pxTimer->xTimerPeriod = xTimerExpirationPeriod;
+
+        /* Convert it_value to ticks, but only if it_value is not 0. If it_value
+         * is 0, then the timer will remain disarmed. */
+        if( TIMESPEC_IS_NOT_ZERO( value->it_value ) )
+        {
+            /* Absolute timeout. */
+            if( ( flags & TIMER_ABSTIME ) == TIMER_ABSTIME )
+            {
+                struct timespec xCurrentTime = { 0 };
+
+                /* Get current time */
+                if( clock_gettime( CLOCK_REALTIME, &xCurrentTime ) != 0 )
+                {
+                    iStatus = EINVAL;
+                }
+                else
+                {
+                    iStatus = UTILS_AbsoluteTimespecToDeltaTicks( &value->it_value, &xCurrentTime, &xNextTimerExpiration );
+                }
+
+                /* Make sure xNextTimerExpiration is zero in case we got negative time difference */
+                if( iStatus != 0 )
+                {
+                    xNextTimerExpiration = 0;
+
+                    if( iStatus == ETIMEDOUT )
+                    {
+                        /* Set Status to 0 as absolute time is past is treated as expiry but not an error */
+                        iStatus = 0;
+                    }
+                }
+            }
+            /* Relative timeout. */
+            else
+            {
+                ( void ) UTILS_TimespecToTicks( &value->it_value, &xNextTimerExpiration );
+            }
+        }
+
+        /* If xNextTimerExpiration is still 0, that means that it_value specified
+         * an absolute timeout in the past. Per POSIX spec, a notification should be
+         * triggered immediately. */
+        if( xNextTimerExpiration == 0 )
+        {
+            prvTimerCallback( xTimerHandle );
+        }
+        else
+        {
+            /* Set the timer to expire at the it_value, then start it. */
+            ( void ) xTimerChangePeriod( xTimerHandle, xNextTimerExpiration, portMAX_DELAY );
+            ( void ) xTimerStart( xTimerHandle, xNextTimerExpiration );
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int timer_gettime( timer_t timerid,
+                   struct itimerspec * value )
+{
+    TimerHandle_t xTimerHandle = timerid;
+    timer_internal_t * pxTimer = ( timer_internal_t * ) pvTimerGetTimerID( xTimerHandle );
+    TickType_t xNextExpirationTime = xTimerGetExpiryTime( xTimerHandle ) - xTaskGetTickCount(),
+               xTimerExpirationPeriod = pxTimer->xTimerPeriod;
+
+    /* Set it_value only if the timer is armed. Otherwise, set it to 0. */
+    if( xTimerIsTimerActive( xTimerHandle ) != pdFALSE )
+    {
+        value->it_value.tv_sec = ( time_t ) ( xNextExpirationTime / configTICK_RATE_HZ );
+        value->it_value.tv_nsec = ( long ) ( ( xNextExpirationTime % configTICK_RATE_HZ ) * NANOSECONDS_PER_TICK );
+    }
+    else
+    {
+        value->it_value.tv_sec = 0;
+        value->it_value.tv_nsec = 0;
+    }
+
+    /* Set it_interval only if the timer is periodic. Otherwise, set it to 0. */
+    if( xTimerExpirationPeriod != portMAX_DELAY )
+    {
+        value->it_interval.tv_sec = ( time_t ) ( xTimerExpirationPeriod / configTICK_RATE_HZ );
+        value->it_interval.tv_nsec = ( long ) ( ( xTimerExpirationPeriod % configTICK_RATE_HZ ) * NANOSECONDS_PER_TICK );
+    }
+    else
+    {
+        value->it_interval.tv_sec = 0;
+        value->it_interval.tv_nsec = 0;
+    }
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_unistd.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_unistd.c
new file mode 100755
index 0000000..0d3d914
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_unistd.c
@@ -0,0 +1,54 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_unistd.c
+ * @brief Implementation of functions in unistd.h
+ */
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/unistd.h"
+
+/*-----------------------------------------------------------*/
+
+unsigned sleep( unsigned seconds )
+{
+    vTaskDelay( pdMS_TO_TICKS( seconds * 1000 ) );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
+
+int usleep( useconds_t usec )
+{
+    /* To avoid delaying for less than usec, always round up. */
+    vTaskDelay( pdMS_TO_TICKS( usec / 1000 + ( usec % 1000 != 0 ) ) );
+
+    return 0;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_utils.c b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_utils.c
new file mode 100755
index 0000000..c121587
--- /dev/null
+++ b/lib/freertos-posix/FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_utils.c
@@ -0,0 +1,388 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file FreeRTOS_POSIX_utils.c
+ * @brief Implementation of utility functions in utils.h
+ */
+
+/* C standard library includes. */
+#include <stddef.h>
+#include <limits.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX.h"
+#include "FreeRTOS_POSIX/errno.h"
+#include "FreeRTOS_POSIX/utils.h"
+
+/*-----------------------------------------------------------*/
+
+size_t UTILS_strnlen( const char * const pcString,
+                      size_t xMaxLength )
+{
+    const char * pcCharPointer = pcString;
+    size_t xLength = 0;
+
+    if( pcString != NULL )
+    {
+        while( ( *pcCharPointer != '\0' ) && ( xLength < xMaxLength ) )
+        {
+            xLength++;
+            pcCharPointer++;
+        }
+    }
+
+    return xLength;
+}
+
+/*-----------------------------------------------------------*/
+
+int UTILS_AbsoluteTimespecToDeltaTicks( const struct timespec * const pxAbsoluteTime,
+                                        const struct timespec * const pxCurrentTime,
+                                        TickType_t * const pxResult )
+{
+    int iStatus = 0;
+    struct timespec xDifference = { 0 };
+
+    /* Check parameters. */
+    if( ( pxAbsoluteTime == NULL ) || ( pxCurrentTime == NULL ) || ( pxResult == NULL ) )
+    {
+        iStatus = EINVAL;
+    }
+
+    /* Calculate the difference between the current time and absolute time. */
+    if( iStatus == 0 )
+    {
+        iStatus = UTILS_TimespecSubtract( pxAbsoluteTime, pxCurrentTime, &xDifference );
+
+        if( iStatus == 1 )
+        {
+            /* pxAbsoluteTime was in the past. */
+            iStatus = ETIMEDOUT;
+        }
+        else if( iStatus == -1 )
+        {
+            /* error */
+            iStatus = EINVAL;
+        }
+    }
+
+    /* Convert the time difference to ticks. */
+    if( iStatus == 0 )
+    {
+        iStatus = UTILS_TimespecToTicks( &xDifference, pxResult );
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int UTILS_TimespecToTicks( const struct timespec * const pxTimespec,
+                           TickType_t * const pxResult )
+{
+    int iStatus = 0;
+    int64_t llTotalTicks = 0;
+    long lNanoseconds = 0;
+
+    /* Check parameters. */
+    if( ( pxTimespec == NULL ) || ( pxResult == NULL ) )
+    {
+        iStatus = EINVAL;
+    }
+    else if( ( iStatus == 0 ) && ( UTILS_ValidateTimespec( pxTimespec ) == false ) )
+    {
+        iStatus = EINVAL;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Convert timespec.tv_sec to ticks. */
+        llTotalTicks = ( int64_t ) configTICK_RATE_HZ * ( pxTimespec->tv_sec );
+
+        /* Convert timespec.tv_nsec to ticks. This value does not have to be checked
+         * for overflow because a valid timespec has 0 <= tv_nsec < 1000000000 and
+         * NANOSECONDS_PER_TICK > 1. */
+        lNanoseconds = pxTimespec->tv_nsec / ( long ) NANOSECONDS_PER_TICK +                  /* Whole nanoseconds. */
+                       ( long ) ( pxTimespec->tv_nsec % ( long ) NANOSECONDS_PER_TICK != 0 ); /* Add 1 to round up if needed. */
+
+        /* Add the nanoseconds to the total ticks. */
+        llTotalTicks += ( int64_t ) lNanoseconds;
+
+        /* Check for overflow */
+        if( llTotalTicks < 0 )
+        {
+            iStatus = EINVAL;
+        }
+        else
+        {
+            /* check if TickType_t is 32 bit or 64 bit */
+            uint32_t ulTickTypeSize = sizeof( TickType_t );
+
+            /* check for downcast overflow */
+            if( ulTickTypeSize == sizeof( uint32_t ) )
+            {
+                if( llTotalTicks > UINT_MAX )
+                {
+                    iStatus = EINVAL;
+                }
+            }
+        }
+
+        /* Write result. */
+        *pxResult = ( TickType_t ) llTotalTicks;
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+void UTILS_NanosecondsToTimespec( int64_t llSource,
+                                  struct timespec * const pxDestination )
+{
+    long lCarrySec = 0;
+
+    /* Convert to timespec. */
+    pxDestination->tv_sec = ( time_t ) ( llSource / NANOSECONDS_PER_SECOND );
+    pxDestination->tv_nsec = ( long ) ( llSource % NANOSECONDS_PER_SECOND );
+
+    /* Subtract from tv_sec if tv_nsec < 0. */
+    if( pxDestination->tv_nsec < 0L )
+    {
+        /* Compute the number of seconds to carry. */
+        lCarrySec = ( pxDestination->tv_nsec / ( long ) NANOSECONDS_PER_SECOND ) + 1L;
+
+        pxDestination->tv_sec -= ( time_t ) ( lCarrySec );
+        pxDestination->tv_nsec += lCarrySec * ( long ) NANOSECONDS_PER_SECOND;
+    }
+}
+
+/*-----------------------------------------------------------*/
+
+int UTILS_TimespecAdd( const struct timespec * const x,
+                       const struct timespec * const y,
+                       struct timespec * const pxResult )
+{
+    int64_t llPartialSec = 0;
+    int iStatus = 0;
+
+    /* Check parameters. */
+    if( ( pxResult == NULL ) || ( x == NULL ) || ( y == NULL ) )
+    {
+        iStatus = -1;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* Perform addition. */
+        pxResult->tv_nsec = x->tv_nsec + y->tv_nsec;
+
+        /* check for overflow in case nsec value was invalid */
+        if( pxResult->tv_nsec < 0 )
+        {
+            iStatus = 1;
+        }
+        else
+        {
+            llPartialSec = ( pxResult->tv_nsec ) / NANOSECONDS_PER_SECOND;
+            pxResult->tv_nsec = ( pxResult->tv_nsec ) % NANOSECONDS_PER_SECOND;
+            pxResult->tv_sec = x->tv_sec + y->tv_sec + llPartialSec;
+
+            /* check for overflow */
+            if( pxResult->tv_sec < 0 )
+            {
+                iStatus = 1;
+            }
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int UTILS_TimespecAddNanoseconds( const struct timespec * const x,
+                                  int64_t llNanoseconds,
+                                  struct timespec * const pxResult )
+{
+    int64_t llTotalNSec = 0;
+    int iStatus = 0;
+
+    /* Check parameters. */
+    if( ( pxResult == NULL ) || ( x == NULL ) )
+    {
+        iStatus = -1;
+    }
+
+    if( iStatus == 0 )
+    {
+        /* add nano seconds */
+        llTotalNSec = x->tv_nsec + llNanoseconds;
+
+        /* check for nano seconds overflow */
+        if( llTotalNSec < 0 )
+        {
+            iStatus = 1;
+        }
+        else
+        {
+            pxResult->tv_nsec = llTotalNSec % NANOSECONDS_PER_SECOND;
+            pxResult->tv_sec = x->tv_sec + ( llTotalNSec / NANOSECONDS_PER_SECOND );
+
+            /* check for seconds overflow */
+            if( pxResult->tv_sec < 0 )
+            {
+                iStatus = 1;
+            }
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int UTILS_TimespecSubtract( const struct timespec * const x,
+                            const struct timespec * const y,
+                            struct timespec * const pxResult )
+{
+    int iCompareResult = 0;
+    int iStatus = 0;
+
+    /* Check parameters. */
+    if( ( pxResult == NULL ) || ( x == NULL ) || ( y == NULL ) )
+    {
+        iStatus = -1;
+    }
+
+    if( iStatus == 0 )
+    {
+        iCompareResult = UTILS_TimespecCompare( x, y );
+
+        /* if x < y then result would be negative, return 1 */
+        if( iCompareResult == -1 )
+        {
+            iStatus = 1;
+        }
+        else if( iCompareResult == 0 )
+        {
+            /* if times are the same return zero */
+            pxResult->tv_sec = 0;
+            pxResult->tv_nsec = 0;
+        }
+        else
+        {
+            /* If x > y Perform subtraction. */
+            pxResult->tv_sec = x->tv_sec - y->tv_sec;
+            pxResult->tv_nsec = x->tv_nsec - y->tv_nsec;
+
+            /* check if nano seconds value needs to borrow */
+            if( pxResult->tv_nsec < 0 )
+            {
+                /* Based on comparison, tv_sec > 0 */
+                pxResult->tv_sec--;
+                pxResult->tv_nsec += ( long ) NANOSECONDS_PER_SECOND;
+            }
+
+            /* if nano second is negative after borrow, it is an overflow error */
+            if( pxResult->tv_nsec < 0 )
+            {
+                iStatus = -1;
+            }
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+int UTILS_TimespecCompare( const struct timespec * const x,
+                           const struct timespec * const y )
+{
+    int iStatus = 0;
+
+    /* Check parameters */
+    if( ( x == NULL ) && ( y == NULL ) )
+    {
+        iStatus = 0;
+    }
+    else if( y == NULL )
+    {
+        iStatus = 1;
+    }
+    else if( x == NULL )
+    {
+        iStatus = -1;
+    }
+    else if( x->tv_sec > y->tv_sec )
+    {
+        iStatus = 1;
+    }
+    else if( x->tv_sec < y->tv_sec )
+    {
+        iStatus = -1;
+    }
+    else
+    {
+        /* seconds are equal compare nano seconds */
+        if( x->tv_nsec > y->tv_nsec )
+        {
+            iStatus = 1;
+        }
+        else if( x->tv_nsec < y->tv_nsec )
+        {
+            iStatus = -1;
+        }
+        else
+        {
+            iStatus = 0;
+        }
+    }
+
+    return iStatus;
+}
+
+/*-----------------------------------------------------------*/
+
+bool UTILS_ValidateTimespec( const struct timespec * const pxTimespec )
+{
+    bool xReturn = false;
+
+    if( pxTimespec != NULL )
+    {
+        /* Verify 0 <= tv_nsec < 1000000000. */
+        if( ( pxTimespec->tv_nsec >= 0 ) &&
+            ( pxTimespec->tv_nsec < NANOSECONDS_PER_SECOND ) )
+        {
+            xReturn = true;
+        }
+    }
+
+    return xReturn;
+}
+
+/*-----------------------------------------------------------*/
diff --git a/lib/freertos-posix/LICENSE b/lib/freertos-posix/LICENSE
new file mode 100644
index 0000000..90228db
--- /dev/null
+++ b/lib/freertos-posix/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2019 FreeRTOS
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/lib/freertos-posix/README.md b/lib/freertos-posix/README.md
new file mode 100644
index 0000000..d01fca3
--- /dev/null
+++ b/lib/freertos-posix/README.md
@@ -0,0 +1,15 @@
+## FreeRTOS+POSIX: Portable Operating System Interface (POSIX threading wrapper) for FreeRTOS
+
+The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. FreeRTOS+POSIX implements a subset of the [POSIX threading](https://pubs.opengroup.org/onlinepubs/7908799/xsh/threads.html) API.
+
+With FreeRTOS+POSIX, an existing POSIX threading compliant application can be ported to run on the FreeRTOS kernel, and therefor leverage all the [Amazon FreeRTOS](https://www.freertos.org/FAQ_Amazon.html) functionality. Additionally, a library designed for use with POSIX threading compatible operating systems can be ported to FreeRTOS kernel based applications.
+
+For more on FreeRTOS+POSIX, please visit [freertos.org](https://www.freertos.org/FreeRTOS-Plus/FreeRTOS_Plus_POSIX/index.html)
+
+This repository only contains source code. For demo applications, please visit https://github.com/FreeRTOS/FreeRTOS-Labs. 
+
+## To consume FreeRTOS+POSIX 
+It is recommended to use this repository as a submodule. Please refer to [Git Tools — Submodules](https://git-scm.com/book/en/v2/Git-Tools-Submodules). 
+
+## Notes
+This project is undergoing optimizations or refactorization to improve memory usage, modularity, documentation, demo usability, or test coverage. 
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/errno.h b/lib/freertos-posix/include/FreeRTOS_POSIX/errno.h
new file mode 100755
index 0000000..136e04b
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/errno.h
@@ -0,0 +1,95 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file errno.h
+ * @brief System error numbers.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html
+ *
+ * The values defined in this file may not be compatible with the strerror
+ * function provided by this system.
+ */
+
+#ifndef _FREERTOS_POSIX_ERRNO_H_
+#define _FREERTOS_POSIX_ERRNO_H_
+
+/* Undefine all errnos to avoid redefinition errors with system errnos. */
+#undef EPERM
+#undef ENOENT
+#undef EBADF
+#undef EAGAIN
+#undef ENOMEM
+#undef EEXIST
+#undef EBUSY
+#undef EINVAL
+#undef ENOSPC
+#undef ERANGE
+#undef ENAMETOOLONG
+#undef EDEADLK
+#undef EOVERFLOW
+#undef ENOSYS
+#undef EMSGSIZE
+#undef ENOTSUP
+#undef ETIMEDOUT
+
+/**
+ * @name Definition of POSIX errnos.
+ */
+/**@{ */
+#define EPERM           1   /**< Operation not permitted. */
+#define ENOENT          2   /**< No such file or directory. */
+#define EBADF           9   /**< Bad file descriptor. */
+#define EAGAIN          11  /**< Resource unavailable, try again. */
+#define ENOMEM          12  /**< Not enough space. */
+#define EEXIST          17  /**< File exists. */
+#define EBUSY           16  /**< Device or resource busy. */
+#define EINVAL          22  /**< Invalid argument. */
+#define ENOSPC          28  /**< No space left on device. */
+#define ERANGE          34  /**< Result too large. */
+#define ENAMETOOLONG    36  /**< File name too long. */
+#define EDEADLK         45  /**< Resource deadlock would occur. */
+#define EOVERFLOW       75  /**< Value too large to be stored in data type. */
+#define ENOSYS          88  /**< Function not supported. */
+#define EMSGSIZE        90  /**< Message too long. */
+#define ENOTSUP         95  /**< Operation not supported. */
+#define ETIMEDOUT       116 /**< Connection timed out. */
+/**@} */
+
+/**
+ * @name System Variable
+ *
+ * @brief Define FreeRTOS+POSIX errno, if enabled.
+ * Set configUSE_POSIX_ERRNO to enable, and clear to disable. See FreeRTOS.h.
+ *
+ * @{
+ */
+#if ( configUSE_POSIX_ERRNO == 1 )
+    extern int FreeRTOS_errno;
+    #define errno    FreeRTOS_errno
+#endif
+/**@} */
+
+#endif /* ifndef _FREERTOS_POSIX_ERRNO_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/fcntl.h b/lib/freertos-posix/include/FreeRTOS_POSIX/fcntl.h
new file mode 100755
index 0000000..1e921ce
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/fcntl.h
@@ -0,0 +1,79 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file fcntl.h
+ * @brief File control options.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/fcntl.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_FCNTL_H_
+#define _FREERTOS_POSIX_FCNTL_H_
+
+/**
+ * @name File creation flags for use in the oflag value to open() and openat().
+ */
+/**@{ */
+#define O_CLOEXEC      0x0001 /**< Close the file descriptor upon exec(). */
+#define O_CREAT        0x0002 /**< Create file if it does not exist. */
+#define O_DIRECTORY    0x0004 /**< Fail if file is a non-directory file. */
+#define O_EXCL         0x0008 /**< Exclusive use flag. */
+#define O_NOCTTY       0x0010 /**< Do not assign controlling terminal. */
+#define O_NOFOLLOW     0x0020 /**< Do not follow symbolic links. */
+#define O_TRUNC        0x0040 /**< Truncate flag. */
+#define O_TTY_INIT     0x0080 /**< termios structure provides conforming behavior. */
+/**@} */
+
+/**
+ * @name File status flags for open(), openat(), and fcntl().
+ */
+/**@{ */
+#define O_APPEND      0x0100 /**< Set append mode. */
+#define O_DSYNC       0x0200 /**< Write according to synchronized I/O data integrity completion. */
+#define O_NONBLOCK    0x0400 /**< Non-blocking mode. */
+#define O_RSYNC       0x0800 /**< Synchronized read I/O operations. */
+#define O_SYNC        0x0200 /**< Write according to synchronized I/O file integrity completion. */
+/**@} */
+
+/**
+ * @name Mask for file access modes.
+ */
+/**@{ */
+#define O_ACCMODE    0xF000
+/**@} */
+
+/**
+ * @name File access modes for open(), openat(), and fcntl().
+ */
+/**@{ */
+#define O_EXEC      0x1000  /**< Open for execute only (non-directory files). */
+#define O_RDONLY    0x2000  /**< Open for reading only. */
+#define O_RDWR      0xA000  /**< Open for reading and writing. */
+#define O_SEARCH    0x4000  /**< Open directory for search only. */
+#define O_WRONLY    0x8000  /**< Open for writing only. */
+/**@} */
+
+#endif /* ifndef _FREERTOS_POSIX_FCNTL_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/mqueue.h b/lib/freertos-posix/include/FreeRTOS_POSIX/mqueue.h
new file mode 100755
index 0000000..7cbf01c
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/mqueue.h
@@ -0,0 +1,250 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file mqueue.h
+ * @brief Message queues.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/mqueue.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_MQUEUE_H_
+#define _FREERTOS_POSIX_MQUEUE_H_
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX/time.h"
+
+/**
+ * @brief Message queue descriptor.
+ */
+typedef void * mqd_t;
+
+/**
+ * @brief Message queue attributes.
+ */
+struct mq_attr
+{
+    long mq_flags;   /**< Message queue flags. */
+    long mq_maxmsg;  /**< Maximum number of messages. */
+    long mq_msgsize; /**< Maximum message size. */
+    long mq_curmsgs; /**< Number of messages currently queued. */
+};
+
+/**
+ * @brief Close a message queue.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_close.html
+ *
+ * @retval 0 - Upon successful completion
+ * @retval -1 - A error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EBADF - The mqdes argument is not a valid message queue descriptor.
+ */
+int mq_close( mqd_t mqdes );
+
+/**
+ * @brief Get message queue attributes.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_getattr.html
+ *
+ * @retval 0 - Upon successful completion
+ * @retval -1 - A error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * DBADF - The mqdes argument is not a valid message queue descriptor.
+ */
+int mq_getattr( mqd_t mqdes,
+                struct mq_attr * mqstat );
+
+/**
+ * @brief Open a message queue.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_open.html
+ *
+ * @note Supported name pattern: leading &lt;slash&gt; character in name is always required;
+ * the maximum length (excluding null-terminator) of the name argument can be NAME_MAX.
+ * The default value of NAME_MAX in FreeRTOS_POSIX_portable_default.h is 64, which can be
+ * overwritten by user.
+ * @note mode argument is not supported.
+ * @note Supported oflags: O_RDWR, O_CREAT, O_EXCL, and O_NONBLOCK.
+ *
+ * @retval Message queue descriptor -- Upon successful completion
+ * @retval (mqd_t) - 1 -- An error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EINVAL - name argument is invalid (not following name pattern),
+ * OR if O_CREAT is specified in oflag with attr argument not NULL and either mq_maxmsg or mq_msgsize is equal to or less than zero,
+ * OR either O_CREAT or O_EXCL is not set and a queue with the same name is unlinked but pending to be removed.
+ * <br>
+ * EEXIST - O_CREAT and O_EXCL are set and the named message queue already exists.
+ * <br>
+ * ENOSPC - There is insufficient space for the creation of the new message queue.
+ * <br>
+ * ENOENT - O_CREAT is not set and the named message queue does not exist.
+ */
+mqd_t mq_open( const char * name,
+               int oflag,
+               mode_t mode,
+               struct mq_attr * attr );
+
+/**
+ * @brief Receive a message from a message queue.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_receive.html
+ *
+ * @note msg_prio argument is not supported. Messages are not checked for corruption.
+ *
+ * @retval The length of the selected message in bytes - Upon successful completion.
+ * The message is removed from the queue
+ * @retval -1 - An error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EBADF - The mqdes argument is not a valid message queue descriptor open for reading.
+ * <br>
+ * EMSGSIZE - The specified message buffer size, msg_len, is less than the message size attribute of the message queue.
+ * <br>
+ * ETIMEDOUT - The O_NONBLOCK flag was not set when the message queue was opened,
+ * but no message arrived on the queue before the specified timeout expired.
+ * <br>
+ * EAGAIN - O_NONBLOCK was set in the message description associated with mqdes, and the specified message queue is empty.
+ */
+ssize_t mq_receive( mqd_t mqdes,
+                    char * msg_ptr,
+                    size_t msg_len,
+                    unsigned int * msg_prio );
+
+/**
+ * @brief Send a message to a message queue.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_send.html
+ *
+ * @note msg_prio argument is not supported.
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval -1 - An error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EBADF - The mqdes argument is not a valid message queue descriptor open for writing.
+ * <br>
+ * EMSGSIZE - The specified message length, msg_len, exceeds the message size attribute of the message queue,
+ * OR insufficient memory for the message to be sent.
+ * <br>
+ * ETIMEDOUT - The O_NONBLOCK flag was not set when the message queue was opened,
+ * but the timeout expired before the message could be added to the queue.
+ * <br>
+ * EAGAIN - The O_NONBLOCK flag is set in the message queue description associated with mqdes,
+ * and the specified message queue is full.
+ */
+int mq_send( mqd_t mqdes,
+             const char * msg_ptr,
+             size_t msg_len,
+             unsigned msg_prio );
+
+/**
+ * @brief Receive a message from a message queue with timeout.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_timedreceive.html
+ *
+ * @note msg_prio argument is not supported. Messages are not checked for corruption.
+ *
+ * @retval The length of the selected message in bytes - Upon successful completion.
+ * The message is removed from the queue
+ * @retval -1 - An error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EBADF - The mqdes argument is not a valid message queue descriptor open for reading.
+ * <br>
+ * EMSGSIZE - The specified message buffer size, msg_len, is less than the message size attribute of the message queue.
+ * <br>
+ * EINVAL - The process or thread would have blocked, and the abstime parameter specified a nanoseconds field value
+ * less than zero or greater than or equal to 1000 million.
+ * <br>
+ * ETIMEDOUT - The O_NONBLOCK flag was not set when the message queue was opened,
+ * but no message arrived on the queue before the specified timeout expired.
+ * <br>
+ * EAGAIN - O_NONBLOCK was set in the message description associated with mqdes, and the specified message queue is empty.
+ */
+ssize_t mq_timedreceive( mqd_t mqdes,
+                         char * msg_ptr,
+                         size_t msg_len,
+                         unsigned * msg_prio,
+                         const struct timespec * abstime );
+
+/**
+ * @brief Send a message to a message queue with timeout.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_timedsend.html
+ *
+ * @note msg_prio argument is not supported.
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval -1 - An error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EBADF - The mqdes argument is not a valid message queue descriptor open for writing.
+ * <br>
+ * EMSGSIZE - The specified message length, msg_len, exceeds the message size attribute of the message queue,
+ * OR insufficient memory for the message to be sent.
+ * <br>
+ * EINVAL - The process or thread would have blocked, and the abstime parameter specified a nanoseconds field
+ * value less than zero or greater than or equal to 1000 million.
+ * <br>
+ * ETIMEDOUT - The O_NONBLOCK flag was not set when the message queue was opened,
+ * but the timeout expired before the message could be added to the queue.
+ * <br>
+ * EAGAIN - The O_NONBLOCK flag is set in the message queue description associated with mqdes,
+ * and the specified message queue is full.
+ */
+int mq_timedsend( mqd_t mqdes,
+                  const char * msg_ptr,
+                  size_t msg_len,
+                  unsigned msg_prio,
+                  const struct timespec * abstime );
+
+/**
+ * @brief Remove a message queue.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_unlink.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval -1 - An error occurred. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EINVAL - name argument is invalid. Refer to requirements on name argument in mq_open().
+ * <br>
+ * ENOENT - The named message queue does not exist.
+ */
+int mq_unlink( const char * name );
+
+#endif /* ifndef _FREERTOS_POSIX_MQUEUE_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/pthread.h b/lib/freertos-posix/include/FreeRTOS_POSIX/pthread.h
new file mode 100755
index 0000000..77f949a
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/pthread.h
@@ -0,0 +1,501 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file pthread.h
+ * @brief Threads.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/pthread.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_PTHREAD_H_
+#define _FREERTOS_POSIX_PTHREAD_H_
+
+/* FreeRTOS+POSIX includes. POSIX states that this header shall make symbols
+ * defined in sched.h and time.h visible. */
+#include "FreeRTOS_POSIX/sched.h"
+#include "FreeRTOS_POSIX/time.h"
+
+/**
+ * @name pthread detach state.
+ */
+/**@{ */
+#define PTHREAD_CREATE_DETACHED    0       /**< Detached. */
+#define PTHREAD_CREATE_JOINABLE    1       /**< Joinable (default). */
+/**@} */
+
+/**
+ * @name Returned to a single thread after a successful pthread_barrier_wait.
+ *
+ * @brief POSIX specifies that "The constant PTHREAD_BARRIER_SERIAL_THREAD is defined in
+ * <pthread.h> and its value shall be distinct from any other value returned by pthread_barrier_wait()."
+ * So it's defined as negative to distinguish it from the errnos, which are positive.
+ */
+#define PTHREAD_BARRIER_SERIAL_THREAD    ( -2 )
+
+/**
+ * @name Mutex types.
+ */
+/**@{ */
+#ifndef PTHREAD_MUTEX_NORMAL
+    #define PTHREAD_MUTEX_NORMAL        0                        /**< Non-robust, deadlock on relock, does not remember owner. */
+#endif
+#ifndef PTHREAD_MUTEX_ERRORCHECK
+    #define PTHREAD_MUTEX_ERRORCHECK    1                        /**< Non-robust, error on relock,  remembers owner. */
+#endif
+#ifndef PTHREAD_MUTEX_RECURSIVE
+    #define PTHREAD_MUTEX_RECURSIVE     2                        /**< Non-robust, recursive relock, remembers owner. */
+#endif
+#ifndef PTHREAD_MUTEX_DEFAULT
+    #define PTHREAD_MUTEX_DEFAULT       PTHREAD_MUTEX_NORMAL     /**< PTHREAD_MUTEX_NORMAL (default). */
+#endif
+/**@} */
+
+/**
+ * @name Compile-time initializers.
+ *
+ * @brief To use PTHREAD_COND_INITIALIZER, posixconfigENABLE_PTHREAD_COND_T needs to be set to 1
+ * in port specific POSIX config file.
+ *
+ * To use PTHREAD_MUTEX_INITIALIZER, posixconfigENABLE_PTHREAD_MUTEX_T needs to be set to 1 in
+ * port specific POSIX config file.
+ */
+/**@{ */
+#if posixconfigENABLE_PTHREAD_COND_T == 1
+    #define PTHREAD_COND_INITIALIZER    FREERTOS_POSIX_COND_INITIALIZER       /**< pthread_cond_t. */
+#endif
+
+#if posixconfigENABLE_PTHREAD_MUTEX_T == 1
+    #define PTHREAD_MUTEX_INITIALIZER    FREERTOS_POSIX_MUTEX_INITIALIZER /**< pthread_mutex_t. */
+#endif
+
+/**@} */
+
+/**
+ * @brief Destroy the thread attributes object.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_destroy.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_attr_destroy( pthread_attr_t * attr );
+
+/**
+ * @brief Get detachstate attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_getdetachstate.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_attr_getdetachstate( const pthread_attr_t * attr,
+                                 int * detachstate );
+
+/**
+ * @brief Get schedparam attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_getschedparam.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_attr_getschedparam( const pthread_attr_t * attr,
+                                struct sched_param * param );
+
+/**
+ * @brief Get stacksize attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_getstacksize.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_attr_getstacksize( const pthread_attr_t * attr,
+                               size_t * stacksize );
+
+/**
+ * @brief Initialize the thread attributes object.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_init.html
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @note Currently, only stack size, sched_param, and detach state attributes
+ * are supported. Also see pthread_attr_get*() and pthread_attr_set*().
+ */
+int pthread_attr_init( pthread_attr_t * attr );
+
+/**
+ * @brief Set detachstate attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_setdetachstate.html
+ *
+ * @retval 0 - Upon successful completion
+ * @retval EINVAL - The value of detachstate is not valid. Currently, supported detach states are --
+ *                  PTHREAD_CREATE_DETACHED and PTHREAD_CREATE_JOINABLE.
+ */
+int pthread_attr_setdetachstate( pthread_attr_t * attr,
+                                 int detachstate );
+
+/**
+ * @brief Set schedparam attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_setschedparam.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The value of param is not valid.
+ * @retval ENOTSUP - An attempt was made to set the attribute to an unsupported value.
+ */
+int pthread_attr_setschedparam( pthread_attr_t * attr,
+                                const struct sched_param * param );
+
+/**
+ * @brief Set the schedpolicy attribute.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_setschedpolicy.html
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @warning This function is a stub and always returns 0.
+ */
+int pthread_attr_setschedpolicy( pthread_attr_t * attr,
+                                 int policy );
+
+/**
+ * @brief Set stacksize attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_attr_setstacksize.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The value of stacksize is less than {PTHREAD_STACK_MIN}.
+ */
+int pthread_attr_setstacksize( pthread_attr_t * attr,
+                               size_t stacksize );
+
+/**
+ * @brief Destroy a barrier object.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_barrier_destroy.html
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @note This function does not validate whether there is any thread blocking on the barrier before destroying.
+ */
+int pthread_barrier_destroy( pthread_barrier_t * barrier );
+
+/**
+ * @brief Initialize a barrier object.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_barrier_init.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The value specified by count is equal to zero.
+ * @retval ENOMEM - count cannot fit into FreeRTOS event group type OR insufficient memory exists to initialize the barrier.
+ *
+ * @note attr is ignored.
+ *
+ * @note pthread_barrier_init() is implemented with FreeRTOS event group.
+ * To ensure count fits in event group, count may be at most 8 when configUSE_16_BIT_TICKS is 1;
+ * it may be at most 24 otherwise. configUSE_16_BIT_TICKS is configured in application FreeRTOSConfig.h
+ * file, which defines how many bits tick count type has. See further details and limitation about event
+ * group and configUSE_16_BIT_TICKS in FreeRTOS site.
+ */
+int pthread_barrier_init( pthread_barrier_t * barrier,
+                          const pthread_barrierattr_t * attr,
+                          unsigned count );
+
+/**
+ * @brief Synchronize at a barrier.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_barrier_wait.html
+ *
+ * @retval PTHREAD_BARRIER_SERIAL_THREAD - Upon successful completion, the first thread.
+ * @retval 0 - Upon successful completion, other thread(s).
+ */
+int pthread_barrier_wait( pthread_barrier_t * barrier );
+
+/**
+ * @brief Thread creation.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_create.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EAGAIN - Insufficient memory for either thread structure or task creation.
+ */
+int pthread_create( pthread_t * thread,
+                    const pthread_attr_t * attr,
+                    void *( *startroutine )( void * ),
+                    void * arg );
+
+/**
+ * @brief Broadcast a condition.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_cond_broadcast.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_cond_broadcast( pthread_cond_t * cond );
+
+/**
+ * @brief Destroy condition variables.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_cond_destroy.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_cond_destroy( pthread_cond_t * cond );
+
+/**
+ * @brief Initialize condition variables.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_cond_init.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval ENOMEM - Insufficient memory exists to initialize the condition variable.
+ *
+ * @note attr is ignored and treated as NULL. Default setting is always used.
+ */
+int pthread_cond_init( pthread_cond_t * cond,
+                       const pthread_condattr_t * attr );
+
+/**
+ * @brief Signal a condition.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_cond_signal.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_cond_signal( pthread_cond_t * cond );
+
+/**
+ * @brief Wait on a condition with a timeout.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_cond_timedwait.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The abstime argument passed in does not refer to an initialized structure OR
+ *                  the abstime parameter specified a nanoseconds field value less than zero or
+ *                  greater than or equal to 1000 million.
+ * @retval ETIMEDOUT - The time specified by abstime to pthread_cond_timedwait() has passed.
+ */
+int pthread_cond_timedwait( pthread_cond_t * cond,
+                            pthread_mutex_t * mutex,
+                            const struct timespec * abstime );
+
+/**
+ * @brief Wait on a condition.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_cond_wait.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_cond_wait( pthread_cond_t * cond,
+                       pthread_mutex_t * mutex );
+
+/**
+ * @brief Compare thread IDs.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_equal.html
+ *
+ * @retval 0 - t1 and t2 are both not NULL && equal.
+ * @retval non-zero - otherwise.
+ */
+int pthread_equal( pthread_t t1,
+                   pthread_t t2 );
+
+/**
+ * @brief Thread termination.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_exit.html
+ *
+ * @retval void - this function cannot return to its caller.
+ */
+void pthread_exit( void * value_ptr );
+
+/**
+ * @brief Dynamic thread scheduling parameters access.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_getschedparam.html
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @note policy is always set to SCHED_OTHER by this function.
+ */
+int pthread_getschedparam( pthread_t thread,
+                           int * policy,
+                           struct sched_param * param );
+
+/**
+ * @brief Wait for thread termination.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_join.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EDEADLK - The value specified by the thread argument to pthread_join() does not refer
+ *                   to a joinable thread OR multiple simultaneous calls to pthread_join()
+ *                   specifying the same target thread OR the value specified by the thread argument
+ *                   to pthread_join() refers to the calling thread.
+ */
+int pthread_join( pthread_t thread,
+                  void ** retval );
+
+/**
+ * @brief Destroy a mutex.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_destroy.html
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @note If there exists a thread holding this mutex, this function returns 0 with mutex not being destroyed.
+ */
+int pthread_mutex_destroy( pthread_mutex_t * mutex );
+
+/**
+ * @brief Initialize a mutex.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_init.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval ENOMEM - Insufficient memory exists to initialize the mutex structure.
+ * @retval EAGAIN - Unable to initialize the mutex structure member(s).
+ */
+int pthread_mutex_init( pthread_mutex_t * mutex,
+                        const pthread_mutexattr_t * attr );
+
+/**
+ * @brief Lock a mutex.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_lock.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - the abstime parameter specified a nanoseconds field value less than zero
+ *                  or greater than or equal to 1000 million.
+ * @retval EDEADLK - The mutex type is PTHREAD_MUTEX_ERRORCHECK and the current thread already
+ *                   owns the mutex.
+ */
+int pthread_mutex_lock( pthread_mutex_t * mutex );
+
+/**
+ * @brief Lock a mutex with timeout.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_timedlock.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The abstime argument passed in does not refer to an initialized structure OR
+ *                  the abstime parameter specified a nanoseconds field value less than zero or
+ *                  greater than or equal to 1000 million.
+ * @retval EDEADLK - The mutex type is PTHREAD_MUTEX_ERRORCHECK and the current thread already owns the mutex.
+ * @retval ETIMEDOUT - The mutex could not be locked before the specified timeout expired.
+ */
+int pthread_mutex_timedlock( pthread_mutex_t * mutex,
+                             const struct timespec * abstime );
+
+/**
+ * @brief Attempt to lock a mutex. Fail immediately if mutex is already locked.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_trylock.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - the abstime parameter specified a nanoseconds field value less than zero
+ *                  or greater than or equal to 1000 million.
+ * @retval EDEADLK - The mutex type is PTHREAD_MUTEX_ERRORCHECK and the current thread already
+ *                   owns the mutex.
+ * @retval EBUSY - The mutex could not be acquired because it was already locked.
+ */
+int pthread_mutex_trylock( pthread_mutex_t * mutex );
+
+/**
+ * @brief Unlock a mutex.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_unlock.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EPERM - The mutex type is PTHREAD_MUTEX_ERRORCHECK or PTHREAD_MUTEX_RECURSIVE, and
+ *                 the current thread does not own the mutex.
+ */
+int pthread_mutex_unlock( pthread_mutex_t * mutex );
+
+/**
+ * @brief Destroy the mutex attributes object.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutexattr_destroy.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_mutexattr_destroy( pthread_mutexattr_t * attr );
+
+/**
+ * @brief Get the mutex type attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutexattr_gettype.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_mutexattr_gettype( const pthread_mutexattr_t * attr,
+                               int * type );
+
+/**
+ * @brief Initialize the mutex attributes object.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutexattr_init.html
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @note Currently, only the type attribute is supported. Also see pthread_mutexattr_settype()
+ *       and pthread_mutexattr_gettype().
+ */
+int pthread_mutexattr_init( pthread_mutexattr_t * attr );
+
+/**
+ * @brief Set the mutex type attribute.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutexattr_settype.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The value type is invalid.
+ */
+int pthread_mutexattr_settype( pthread_mutexattr_t * attr,
+                               int type );
+
+/**
+ * @brief Get the calling thread ID.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_self.html
+ *
+ * @retval the thread ID of the calling thread.
+ */
+pthread_t pthread_self( void );
+
+/**
+ * @brief Dynamic thread scheduling parameters access.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_setschedparam.html
+ *
+ * @note policy is ignored; only priority (param.sched_priority) may be changed.
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int pthread_setschedparam( pthread_t thread,
+                           int policy,
+                           const struct sched_param * param );
+
+#endif /* _FREERTOS_POSIX_PTHREAD_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/sched.h b/lib/freertos-posix/include/FreeRTOS_POSIX/sched.h
new file mode 100755
index 0000000..5a72c44
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/sched.h
@@ -0,0 +1,84 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file sched.h
+ * @brief Execution scheduling.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sched.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_SCHED_H_
+#define _FREERTOS_POSIX_SCHED_H_
+
+/**
+ * @name Scheduling Policies
+ */
+/**@{ */
+#define SCHED_OTHER    0    /**< Another scheduling policy. */
+/**@} */
+
+/**
+ * @brief Scheduling parameters required for implementation of each supported
+ * scheduling policy.
+ */
+struct sched_param
+{
+    int sched_priority; /**< Process or thread execution scheduling priority. */
+};
+
+/**
+ * @brief Get priority limit (max).
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_get_priority_max.html
+ *
+ * @note policy is ignored.
+ *
+ * @return the maximum priority value (0-based) system configuration allows.
+ * <br>
+ * e.g. if configMAX_PRIORITIES == 7, this function returns (configMAX_PRIORITIES - 1).
+ * configMAX_PRIORITIES is configured in application FreeRTOSConfig.h file.
+ */
+int sched_get_priority_max( int policy );
+
+/**
+ * @brief Get priority limit (min).
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_get_priority_min.html
+ *
+ * @note policy is ignored.
+ */
+int sched_get_priority_min( int policy );
+
+/**
+ * @brief Yield the processor.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_yield.html
+ *
+ * @retval 0 - Upon successful completion
+ */
+int sched_yield( void );
+
+#endif /* ifndef _FREERTOS_POSIX_SCHED_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/semaphore.h b/lib/freertos-posix/include/FreeRTOS_POSIX/semaphore.h
new file mode 100755
index 0000000..fa1da91
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/semaphore.h
@@ -0,0 +1,143 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file semaphore.h
+ * @brief Semaphores.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/semaphore.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_SEMAPHORE_H_
+#define _FREERTOS_POSIX_SEMAPHORE_H_
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX/time.h"
+#include "FreeRTOS_POSIX_types.h"
+
+/**
+ * @brief Semaphore type.
+ */
+typedef PosixSemType_t sem_t;
+
+/**
+ * @brief Destroy an unnamed semaphore.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_destroy.html
+ *
+ * @retval 0 - upon successful completion
+ *
+ * @note Semaphore is destroyed regardless of whether there is any thread currently blocked on this semaphore.
+ */
+int sem_destroy( sem_t * sem );
+
+/**
+ * @brief Get the value of a semaphore.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_getvalue.html
+ *
+ * @retval 0 - Upon successful completion
+ *
+ * @note If sem is locked, then the object to which sval points is set to zero.
+ */
+int sem_getvalue( sem_t * sem,
+                  int * sval );
+
+/**
+ * @brief Initialize an unnamed semaphore.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_init.html
+ *
+ * @note pshared is ignored. Semaphores will always be considered "shared".
+ *
+ * @retval 0 - upon successful completion
+ * @retval -1 - otherwise. System error variable errno is also set in this case.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EINVAL -  The value argument exceeds {SEM_VALUE_MAX}.
+ * <br>
+ * ENOSPC - A resource required to initialize the semaphore has been exhausted.
+ */
+int sem_init( sem_t * sem,
+              int pshared,
+              unsigned value );
+
+/**
+ * @brief Unlock a semaphore.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_post.html
+ *
+ * @retval 0 - upon successful completion
+ */
+int sem_post( sem_t * sem );
+
+/**
+ * @brief Lock a semaphore with timeout.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_timedwait.html
+ *
+ * @retval 0 - upon successful completion
+ * @retval -1 - otherwise. System error variable errno is also set in this case.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EINVAL - parameter specified a nanoseconds field value less than zero or greater
+ * than or equal to 1000 million
+ * <br>
+ * ETIMEDOUT - The semaphore could not be locked before the specified timeout expired.
+ *
+ * @note Deadlock detection is not implemented.
+ */
+int sem_timedwait( sem_t * sem,
+                   const struct timespec * abstime );
+
+/**
+ * @brief Lock a semaphore if available.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_trywait.html
+ *
+ * @retval 0 - upon successful completion
+ * @retval -1 - otherwise. System error variable errno is also set in this case.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EAGAIN - The semaphore was already locked, so it cannot be immediately locked by the sem_trywait() operation.
+ */
+int sem_trywait( sem_t * sem );
+
+/**
+ * @brief Lock a semaphore.
+ *
+ * @see http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_wait.html
+ *
+ * @retval 0 - upon successful completion
+ * @retval -1 - otherwise. System error variable errno is also set in this case.
+ *
+ * @note Deadlock detection is not implemented.
+ */
+int sem_wait( sem_t * sem );
+
+#endif /* ifndef _FREERTOS_POSIX_SEMAPHORE_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/signal.h b/lib/freertos-posix/include/FreeRTOS_POSIX/signal.h
new file mode 100755
index 0000000..8f9cc6d
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/signal.h
@@ -0,0 +1,70 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file signal.h
+ * @brief Signals.
+ *
+ * Signals are currently not implemented in FreeRTOS+POSIX. This header only
+ * defines the signal data structures used elsewhere.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/signal.h.html
+ */
+
+
+#ifndef _FREERTOS_POSIX_SIGNAL_H_
+#define _FREERTOS_POSIX_SIGNAL_H_
+
+/**
+ * @name Values of sigev_notify.
+ */
+/**@{ */
+#define SIGEV_NONE      0 /**< No asynchronous notification is delivered when the event of interest occurs. */
+#define SIGEV_SIGNAL    1 /**< A queued signal, with an application-defined value, is generated when the event of interest occurs. Not supported. */
+#define SIGEV_THREAD    2 /**< A notification function is called to perform notification. */
+/**@} */
+
+/**
+ * @brief Signal value.
+ */
+union sigval
+{
+    int sival_int;    /**< Integer signal value. */
+    void * sival_ptr; /**< Pointer signal value. */
+};
+
+/**
+ * @brief Signal event structure.
+ */
+struct sigevent
+{
+    int sigev_notify;                                 /**< Notification type. A value of SIGEV_SIGNAL is not supported. */
+    int sigev_signo;                                  /**< Signal number. This member is ignored. */
+    union sigval sigev_value;                         /**< Signal value. Only the sival_ptr member is used. */
+    void ( * sigev_notify_function )( union sigval ); /**< Notification function. */
+    pthread_attr_t * sigev_notify_attributes;         /**< Notification attributes. */
+};
+
+#endif /* ifndef _FREERTOS_POSIX_SIGNAL_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/sys/types.h b/lib/freertos-posix/include/FreeRTOS_POSIX/sys/types.h
new file mode 100755
index 0000000..9cb3428
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/sys/types.h
@@ -0,0 +1,191 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file sys/types.h
+ * @brief Data types.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_types.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_TYPES_H_
+#define _FREERTOS_POSIX_TYPES_H_
+
+/* C standard library includes. */
+#include <stdint.h>
+
+/* FreeRTOS types include */
+#include "FreeRTOS_POSIX_types.h"
+
+/**
+ * @brief Used for system times in clock ticks or CLOCKS_PER_SEC.
+ *
+ * Enabled/disabled by posixconfigENABLE_CLOCK_T.
+ */
+#if !defined( posixconfigENABLE_CLOCK_T ) || ( posixconfigENABLE_CLOCK_T == 1 )
+    typedef uint32_t                 clock_t;
+#endif
+
+/**
+ * @brief Used for clock ID type in the clock and timer functions.
+ *
+ * Enabled/disabled by posixconfigENABLE_CLOCKID_T.
+ */
+#if !defined( posixconfigENABLE_CLOCKID_T ) || ( posixconfigENABLE_CLOCKID_T == 1 )
+    typedef int                      clockid_t;
+#endif
+
+/**
+ * @brief Used for some file attributes.
+ *
+ * Enabled/disabled by posixconfigENABLE_MODE_T.
+ */
+#if !defined( posixconfigENABLE_MODE_T ) || ( posixconfigENABLE_MODE_T == 1 )
+    typedef int                      mode_t;
+#endif
+
+/**
+ * @brief Used for process IDs and process group IDs.
+ *
+ * Enabled/disabled by posixconfigENABLE_PID_T.
+ */
+#if !defined( posixconfigENABLE_PID_T ) || ( posixconfigENABLE_PID_T == 1 )
+    typedef int                      pid_t;
+#endif
+
+/**
+ * @brief Used to identify a thread attribute object.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_ATTR_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_ATTR_T ) || ( posixconfigENABLE_PTHREAD_ATTR_T == 1 )
+    typedef PthreadAttrType_t        pthread_attr_t;
+#endif
+
+/**
+ * @brief Used to identify a barrier.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_BARRIER_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_BARRIER_T ) || ( posixconfigENABLE_PTHREAD_BARRIER_T == 1 )
+    typedef PthreadBarrierType_t     pthread_barrier_t;
+#endif
+
+/**
+ * @brief Used to define a barrier attributes object.
+ */
+typedef void                         * pthread_barrierattr_t;
+
+/**
+ * @brief Used for condition variables.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_COND_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_COND_T ) || ( posixconfigENABLE_PTHREAD_COND_T == 1 )
+    typedef  PthreadCondType_t       pthread_cond_t;
+#endif
+
+/**
+ * @brief Used to identify a condition attribute object.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_CONDATTR_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_CONDATTR_T ) || ( posixconfigENABLE_PTHREAD_CONDATTR_T == 1 )
+    typedef void                     * pthread_condattr_t;
+#endif
+
+/**
+ * @brief Used for mutexes.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_MUTEX_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_MUTEX_T ) || ( posixconfigENABLE_PTHREAD_MUTEX_T == 1 )
+    typedef PthreadMutexType_t       pthread_mutex_t;
+#endif
+
+/**
+ * @brief Used to identify a mutex attribute object.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_MUTEXATTR_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_MUTEXATTR_T ) || ( posixconfigENABLE_PTHREAD_MUTEXATTR_T == 1 )
+    typedef PthreadMutexAttrType_t   pthread_mutexattr_t;
+#endif
+
+/**
+ * @brief Used to identify a thread.
+ *
+ * Enabled/disabled by posixconfigENABLE_PTHREAD_T.
+ */
+#if !defined( posixconfigENABLE_PTHREAD_T ) || ( posixconfigENABLE_PTHREAD_T == 1 )
+    typedef void                     * pthread_t;
+#endif
+
+/**
+ * @brief Used for a count of bytes or an error indication.
+ *
+ * Enabled/disabled by posixconfigENABLE_SSIZE_T.
+ */
+#if !defined( posixconfigENABLE_SSIZE_T ) || ( posixconfigENABLE_SSIZE_T == 1 )
+    typedef int                      ssize_t;
+#endif
+
+/**
+ * @brief Used for time in seconds.
+ *
+ * Enabled/disabled by posixconfigENABLE_TIME_T.
+ */
+#if !defined( posixconfigENABLE_TIME_T ) || ( posixconfigENABLE_TIME_T == 1 )
+    typedef int64_t                  time_t;
+#endif
+
+/**
+ * @brief Used for timer ID returned by timer_create().
+ *
+ * Enabled/disabled by posixconfigENABLE_TIMER_T.
+ */
+#if !defined( posixconfigENABLE_TIMER_T ) || ( posixconfigENABLE_TIMER_T == 1 )
+    typedef void                     * timer_t;
+#endif
+
+/**
+ * @brief Used for time in microseconds.
+ *
+ * Enabled/disabled by posixconfigENABLE_USECONDS_T.
+ */
+#if !defined( posixconfigENABLE_USECONDS_T ) || ( posixconfigENABLE_USECONDS_T == 1 )
+    typedef unsigned long            useconds_t;
+#endif
+
+/**
+ * @brief Used for file sizes.
+ *
+ * Enabled/disabled by posixconfigENABLE_OFF_T.
+ */
+#if !defined( posixconfigENABLE_OFF_T ) || ( posixconfigENABLE_OFF_T == 1 )
+    typedef long int                 off_t;
+#endif
+
+#endif /* ifndef _FREERTOS_POSIX_TYPES_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/time.h b/lib/freertos-posix/include/FreeRTOS_POSIX/time.h
new file mode 100755
index 0000000..d04de0f
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/time.h
@@ -0,0 +1,258 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file time.h
+ * @brief Time types.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/time.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_TIME_H_
+#define _FREERTOS_POSIX_TIME_H_
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX/sys/types.h"
+#include "FreeRTOS_POSIX/signal.h"
+
+/**
+ * @name Unit conversion constants.
+ */
+/**@{ */
+#define MICROSECONDS_PER_SECOND    ( 1000000LL )                                   /**< Microseconds per second. */
+#define NANOSECONDS_PER_SECOND     ( 1000000000LL )                                /**< Nanoseconds per second. */
+#define NANOSECONDS_PER_TICK       ( NANOSECONDS_PER_SECOND / configTICK_RATE_HZ ) /**< Nanoseconds per FreeRTOS tick. */
+/**@} */
+
+/**
+ * @name Clock identifiers.
+ */
+/**@{ */
+#define CLOCK_REALTIME     0     /**< The identifier of the system-wide clock measuring real time. */
+#define CLOCK_MONOTONIC    1     /**< The identifier for the system-wide monotonic clock.*/
+/**@} */
+
+/**
+ * @name A number used to convert the value returned by the clock() function into seconds.
+ */
+/**@{ */
+#define CLOCKS_PER_SEC    ( ( clock_t ) configTICK_RATE_HZ )
+/**@} */
+
+/**
+ * @name Flag indicating time is absolute.
+ *
+ * For functions taking timer objects, this refers to the clock associated with the timer.
+ */
+/**@{ */
+#define TIMER_ABSTIME    0x01
+/**@} */
+
+#if !defined( posixconfigENABLE_TIMESPEC ) || ( posixconfigENABLE_TIMESPEC == 1 )
+
+/**
+ * @brief represents an elapsed time
+ */
+    struct timespec
+    {
+        time_t tv_sec; /**< Seconds. */
+        long tv_nsec;  /**< Nanoseconds. */
+    };
+#endif
+
+#if !defined( posixconfigENABLE_ITIMERSPEC ) || ( posixconfigENABLE_ITIMERSPEC == 1 )
+
+/**
+ * @brief timer
+ */
+    struct itimerspec
+    {
+        struct timespec it_interval; /**< Timer period. */
+        struct timespec it_value;    /**< Timer expiration. */
+    };
+#endif
+
+/**
+ * @brief Report CPU time used.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock.html
+ *
+ * @return  The number of FreeRTOS ticks since the scheduler
+ * was started minus the ticks spent in the idle task.
+ *
+ * @note This function does NOT report the number of ticks spent by the calling thread.
+ */
+clock_t clock( void );
+
+/**
+ * @brief Access a process CPU-time clock.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock_getcpuclockid.html
+ *
+ * @retval EPERM
+ *
+ * @note This function is currently unsupported.
+ *
+ */
+int clock_getcpuclockid( pid_t pid,
+                         clockid_t * clock_id );
+
+/**
+ * @brief Returns the resolution of a clock.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock_getres.html
+ *
+ * @note clock_id is ignored
+ * @note This function stores the resolution of the FreeRTOS tick count in the object res points to.
+ *
+ * @retval 0 - Upon successful execution
+ */
+int clock_getres( clockid_t clock_id,
+                  struct timespec * res );
+
+/**
+ * @brief Returns the current value for the specified clock, clock_id.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock_gettime.html
+ *
+ * @note clock_id is ignored
+ * @note  this function does not check for overflows of time_t.
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int clock_gettime( clockid_t clock_id,
+                   struct timespec * tp );
+
+/**
+ * @brief High resolution sleep with specifiable clock.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock_nanosleep.html
+ *
+ * @note clock_id is ignored, as this function uses the FreeRTOS tick count as its clock.
+ * @note flags is ignored, if INCLUDE_vTaskDelayUntil is 0. i.e. the FreeRTOS function vTaskDelayUntil isn't available.
+ * @note rmtp is also ignored, as signals are not implemented.
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval EINVAL - The rqtp argument specified a nanosecond value less than zero or greater than or equal to 1000 million.
+ */
+int clock_nanosleep( clockid_t clock_id,
+                     int flags,
+                     const struct timespec * rqtp,
+                     struct timespec * rmtp );
+
+/**
+ * @brief Sets the time for the specified clock.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock_settime.html
+ *
+ * @retval -1 with errno set to EPERM.
+ *
+ * @note This function is currently unsupported, as FreeRTOS does not provide a function to modify the tick count.
+ */
+int clock_settime( clockid_t clock_id,
+                   const struct timespec * tp );
+
+/**
+ * @brief High resolution sleep.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/nanosleep.html
+ *
+ * @note rmtp is ignored, as signals are not implemented.
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval -1 - The rqtp argument is invalid OR the rqtp argument specified a nanosecond value less than zero or greater than or equal to 1000 million.
+ *
+ */
+int nanosleep( const struct timespec * rqtp,
+               struct timespec * rmtp );
+
+/**
+ * @brief Create a per-process timer.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_create.html
+ *
+ * @note clock_id is ignored, as this function used the FreeRTOS tick count as its clock.
+ * @note evp.sigev_notify must be set to SIGEV_THREAD, since signals are currently not supported.
+ *
+ * @retval 0 - Upon successful completion, with location referenced by timerid updated.
+ * @retval -1 - If an error occurs. errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * ENOTSUP - If evp is NULL OR evp->sigen_notify == SIGEV_SIGNAL.
+ * <br>
+ * EAGAIN - The system lacks sufficient signal queuing resources to honor the request.
+ */
+int timer_create( clockid_t clockid,
+                  struct sigevent * evp,
+                  timer_t * timerid );
+
+/**
+ * @brief Delete a per-process timer.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_delete.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int timer_delete( timer_t timerid );
+
+/**
+ * @brief Get the timer overrun count.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_getoverrun.html
+ *
+ * @retval 0 - Always return 0, since signals are not supported.
+ */
+int timer_getoverrun( timer_t timerid );
+
+/**
+ * @brief Get the amount of time until the timer expires.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_gettime.html
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int timer_gettime( timer_t timerid,
+                   struct itimerspec * value );
+
+/**
+ * @brief Set the time until the next expiration of the timer.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_settime.html
+ *
+ * @retval 0 - Upon successful completion.
+ * @retval -1 - An error occurred, errno is also set.
+ *
+ * @sideeffect Possible errno values
+ * <br>
+ * EINVAL - A value structure specified a nanosecond value less than zero or greater than or equal to 1000 million,
+ * AND the it_value member of that structure did not specify zero seconds and nanoseconds.
+ */
+int timer_settime( timer_t timerid,
+                   int flags,
+                   const struct itimerspec * value,
+                   struct itimerspec * ovalue );
+
+#endif /* ifndef _FREERTOS_POSIX_TIME_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/unistd.h b/lib/freertos-posix/include/FreeRTOS_POSIX/unistd.h
new file mode 100755
index 0000000..3b8af22
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/unistd.h
@@ -0,0 +1,61 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file unistd.h
+ * @brief Standard symbolic constants and types
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
+ */
+
+#ifndef _FREERTOS_POSIX_UNISTD_H_
+#define _FREERTOS_POSIX_UNISTD_H_
+
+#include "FreeRTOS_POSIX/sys/types.h"
+
+/**
+ * @brief Suspend execution for an interval of time.
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/sleep.html
+ *
+ * @param[in] seconds The number of seconds to suspend execution.
+ *
+ * @retval 0 - Upon successful completion.
+ *
+ * @note Return value of a positive number is not yet supported.
+ */
+unsigned sleep( unsigned seconds );
+
+/**
+ * @brief Suspend execution for microsecond intervals.
+ *
+ * This is a useful, non-POSIX function.
+ * @param[in] usec The number of microseconds to suspend execution.
+ *
+ * @retval 0 - Upon successful completion.
+ */
+int usleep( useconds_t usec );
+
+#endif /* ifndef _FREERTOS_POSIX_UNISTD_H_ */
diff --git a/lib/freertos-posix/include/FreeRTOS_POSIX/utils.h b/lib/freertos-posix/include/FreeRTOS_POSIX/utils.h
new file mode 100755
index 0000000..c893a95
--- /dev/null
+++ b/lib/freertos-posix/include/FreeRTOS_POSIX/utils.h
@@ -0,0 +1,155 @@
+/*
+ * Amazon FreeRTOS POSIX V1.1.0
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file utils.h
+ * @brief Utility functions used by FreeRTOS+POSIX.
+ */
+
+#ifndef _FREERTOS_POSIX_UTILS_
+#define _FREERTOS_POSIX_UTILS_
+
+/* C standard library includes. */
+#include <stdbool.h>
+#include <stdint.h>
+
+/* FreeRTOS+POSIX includes. */
+#include "FreeRTOS_POSIX/time.h"
+
+/**
+ * @brief Calculates the length of pcString, up to xMaxLength.
+ *
+ * @param[in] pcString The string to find the length of.
+ * @param[in] xMaxLength The limit when searching for the end of pcString.
+ *
+ * @return 0 if pcString is NULL; otherwise, the length of pcString or xMaxLength,
+ * whichever is smaller.
+ */
+size_t UTILS_strnlen( const char * const pcString,
+                      size_t xMaxLength );
+
+/**
+ * @brief Calculates the number of ticks between now and a given timespec.
+ *
+ * @param[in] pxAbsoluteTime A time in the future, specified as seconds and
+ * nanoseconds since CLOCK_REALTIME's 0.
+ * @param[in] pxCurrentTime current time, specified as seconds and
+ * nanoseconds.
+ * @param[out] pxResult Where the result of the conversion is stored. The result
+ * is rounded up for fractional ticks.
+ *
+ * @return 0 on success. Otherwise, ETIMEDOUT if pxAbsoluteTime is in the past,
+ * or EINVAL for invalid parameters.
+ */
+int UTILS_AbsoluteTimespecToDeltaTicks( const struct timespec * const pxAbsoluteTime,
+                                        const struct timespec * const pxCurrentTime,
+                                        TickType_t * const pxResult );
+
+/**
+ * @brief Converts a struct timespec to FreeRTOS ticks.
+ *
+ * @param[in] pxTimespec The timespec to convert.
+ * @param[out] Where the result of the conversion is stored. The result is rounded
+ * up for fractional ticks.
+ *
+ * @return 0 on success. Otherwise, EINVAL for invalid parameters.
+ */
+int UTILS_TimespecToTicks( const struct timespec * const pxTimespec,
+                           TickType_t * const pxResult );
+
+/**
+ * @brief Converts an integer value to a timespec.
+ *
+ * @param[in] llSource The value to convert.
+ * @param[out] pxDestination Where to store the converted value.
+ *
+ * @return No return value.
+ */
+void UTILS_NanosecondsToTimespec( int64_t llSource,
+                                  struct timespec * const pxDestination );
+
+/**
+ * @brief Calculates pxResult = x + y.
+ *
+ * @param[in] x The first argument for addition.
+ * @param[in] y The second argument for addition.
+ * @param[out] pxResult Where the result of the calculation is stored.
+ *
+ * @return -1 if any argument was NULL; 1 if result is negative (overflow); otherwise, 0.
+ */
+int UTILS_TimespecAdd( const struct timespec * const x,
+                       const struct timespec * const y,
+                       struct timespec * const pxResult );
+
+/**
+ * @brief Calculates pxResult = x + ( struct timespec ) nanosec.
+ *
+ * @param[in] x The first argument for addition.
+ * @param[in] llNanoseconds The second argument for addition.
+ * @param[out] pxResult Where the result of the calculation is stored.
+ *
+ * @return -1 if pxResult or x was NULL; 1 if result is negative; otherwise, 0.
+ */
+int UTILS_TimespecAddNanoseconds( const struct timespec * const x,
+                                  int64_t llNanoseconds,
+                                  struct timespec * const pxResult );
+
+/**
+ * @brief Calculates pxResult = x - y. If the result is negative contents of
+ * pResult are undefined
+ *
+ * @param[in] x The first argument for subtraction.
+ * @param[in] y The second argument for subtraction.
+ * @param[out] pxResult Where the result of the calculation is stored.
+ *
+ * @return -1 if any argument was NULL; 1 if result is negative; otherwise, 0.
+ */
+int UTILS_TimespecSubtract( const struct timespec * const x,
+                            const struct timespec * const y,
+                            struct timespec * const pxResult );
+
+/**
+ * @brief Compare  x == y.
+ *
+ * @param[in] x The first argument for comparison.
+ * @param[in] y The second argument for comparison.
+ *
+ * @return 0 if x == y; 1 if x > y; -1 if x < y or any argument was NULL
+ */
+int UTILS_TimespecCompare( const struct timespec * const x,
+                           const struct timespec * const y );
+
+/**
+ * @brief Checks that a timespec conforms to POSIX.
+ *
+ * A valid timespec must have 0 <= tv_nsec < 1000000000.
+ *
+ * @param[in] pxTimespec The timespec to validate.
+ *
+ * @return true if the pxTimespec is valid, false otherwise.
+ */
+bool UTILS_ValidateTimespec( const struct timespec * const pxTimespec );
+
+#endif /* ifndef _FREERTOS_POSIX_UTILS_ */
diff --git a/lib/freertos-posix/include/private/iot_doubly_linked_list.h b/lib/freertos-posix/include/private/iot_doubly_linked_list.h
new file mode 100755
index 0000000..338c539
--- /dev/null
+++ b/lib/freertos-posix/include/private/iot_doubly_linked_list.h
@@ -0,0 +1,242 @@
+/*
+ * Amazon FreeRTOS Common V1.0.0
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/**
+ * @file iot_doubly_linked_list.h
+ * @brief Doubly Linked List implementation.
+ *
+ * A generic implementation of circular Doubly Linked List which consists of a
+ * list head and some list entries (zero in case of an empty list).
+ *
+ * To start with, a structure of type Link_t should be embedded in the structure
+ * which is to be organized as doubly linked list.
+ * @code
+ * typedef struct UserStruct
+ * {
+ *     uint32_t ulField1;
+ *     uint32_t ulField2;
+ *     Link_t xLink;
+ * } UserStruct_t;
+ * @endcode
+ *
+ * A List head should then be defined and initialized.
+ * @code
+ * Link_t xListHead;
+ * listINIT_HEAD( &xListHead );
+ * @endcode
+ *
+ * listADD can then be used to add nodes to the list.
+ * @code
+ * listADD( &( xListHead ), &( pxUserStruct->xLink ) );
+ * @endcode
+ *
+ * listFOR_EACH can be used for traversing the list.
+ * @code
+ * Link_t *pxLink;
+ * UserStruct_t *pxUserStruct;
+ * listFOR_EACH( pxLink, &( xListHead ) )
+ * {
+ *      pxUserStruct = listCONTAINER( pxLink, UserStruct_t, xLink );
+ * }
+ * @endcode
+ *
+ * listFOR_EACH_SAFE should be used if you want to perform destructive operations
+ * (like free) on nodes while traversing the list.
+ * @code
+ * Link_t *pxLink, *pxTempLink;
+ * UserStruct_t *pxUserStruct;
+ * listFOR_EACH( pxLink, pxTempLink, &( xListHead ) )
+ * {
+ *      pxUserStruct = listCONTAINER( pxLink, UserStruct_t, xLink );
+ *      free( pxUserStruct );
+ * }
+ * @endcode
+ */
+
+#ifndef _AWS_DOUBLY_LINKED_LIST_H_
+#define _AWS_DOUBLY_LINKED_LIST_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+/**
+ * @brief Struct embedded in any struct to make it a doubly linked
+ * list.
+ *
+ * pxNext in the head points to the first node in the list and pxPrev
+ * in the head points to the last node in the list. In case of empty
+ * list, both pxPrev and pxNext in the head point to the head node itself.
+ */
+typedef struct Link
+{
+    struct Link * pxPrev; /**< Pointer to the previous node. */
+    struct Link * pxNext; /**< Pointer to the next node. */
+} Link_t;
+
+/**
+ * @brief Initializes the given list head to an empty list.
+ *
+ * @param[in] pxHead The given list head to initialize.
+ */
+#define listINIT_HEAD( pxHead )          \
+    {                                    \
+        ( pxHead )->pxPrev = ( pxHead ); \
+        ( pxHead )->pxNext = ( pxHead ); \
+    }
+
+/**
+ * @brief Adds the given new node to the given list.
+ *
+ * @param[in] pxHead The head of the given list.
+ * @param[in] pxLink The given new node to be added to the given
+ * list.
+ */
+#define listADD( pxHead, pxLink )                     \
+    {                                                 \
+        Link_t * pxPrevLink = ( pxHead );             \
+        Link_t * pxNextLink = ( ( pxHead )->pxNext ); \
+                                                      \
+        ( pxLink )->pxNext = pxNextLink;              \
+        pxNextLink->pxPrev = ( pxLink );              \
+        pxPrevLink->pxNext = ( pxLink );              \
+        ( pxLink )->pxPrev = ( pxPrevLink );          \
+    }
+
+/**
+ * @brief Removes the given node from the list it is part of.
+ *
+ * If the given node is not a part of any list (i.e. next and previous
+ * nodes are NULL), nothing happens.
+ *
+ * @param[in] pxLink The given node to remove from the list.
+ */
+#define listREMOVE( pxLink )                                            \
+    {                                                                   \
+        /* If the link is part of a list, remove it from the list. */   \
+        if( ( pxLink )->pxNext != NULL && ( pxLink )->pxPrev != NULL )  \
+        {                                                               \
+            ( pxLink )->pxPrev->pxNext = ( pxLink )->pxNext;            \
+            ( pxLink )->pxNext->pxPrev = ( pxLink )->pxPrev;            \
+        }                                                               \
+                                                                        \
+        /* Make sure that this link is not part of any list anymore. */ \
+        ( pxLink )->pxPrev = NULL;                                      \
+        ( pxLink )->pxNext = NULL;                                      \
+    }
+
+/**
+ * @brief Given the head of a list, checks if the list is empty.
+ *
+ * @param[in] pxHead The head of the given list.
+ */
+#define listIS_EMPTY( pxHead )    ( ( ( pxHead ) == NULL ) || ( ( pxHead )->pxNext == ( pxHead ) ) )
+
+/**
+ * @brief Removes the first node from the given list and returns it.
+ *
+ * Removes the first node from the given list and assigns it to the
+ * pxLink parameter. If the list is empty, it assigns NULL to the
+ * pxLink.
+ *
+ * @param[in] pxHead The head of the list from which to remove the
+ * first node.
+ * @param[out] pxLink The output parameter to receive the removed
+ * node.
+ */
+#define listPOP( pxHead, pxLink )                                           \
+    {                                                                       \
+        if( listIS_EMPTY( ( pxHead ) ) )                                    \
+        {                                                                   \
+            ( pxLink ) = NULL;                                              \
+        }                                                                   \
+        else                                                                \
+        {                                                                   \
+            ( pxLink ) = ( pxHead )->pxNext;                                \
+            /* If the link is part of a list, remove it from the list. */   \
+            if( ( pxLink )->pxNext != NULL && ( pxLink )->pxPrev != NULL )  \
+            {                                                               \
+                ( pxLink )->pxPrev->pxNext = ( pxLink )->pxNext;            \
+                ( pxLink )->pxNext->pxPrev = ( pxLink )->pxPrev;            \
+            }                                                               \
+                                                                            \
+            /* Make sure that this link is not part of any list anymore. */ \
+            ( pxLink )->pxPrev = NULL;                                      \
+            ( pxLink )->pxNext = NULL;                                      \
+        }                                                                   \
+    }
+
+/**
+ * @brief Merges a list into a given list.
+ *
+ * @param[in] pxHeadResultList The head of the given list into which the
+ * other list should be merged.
+ * @param[in] pxHeadListToMerge The head of the list to be merged into the
+ * given list.
+ */
+#define listMERGE( pxHeadResultList, pxHeadListToMerge )                                     \
+    {                                                                                        \
+        if( !listIS_EMPTY( ( pxHeadListToMerge ) ) )                                         \
+        {                                                                                    \
+            /* Setup links between last node of listToMerge and first node of resultList. */ \
+            ( pxHeadListToMerge )->pxPrev->pxNext = ( pxHeadResultList )->pxNext;            \
+            ( pxHeadResultList )->pxNext->pxPrev = ( pxHeadListToMerge )->pxPrev;            \
+                                                                                             \
+            /* Setup links between first node of listToMerge and the head of resultList. */  \
+            ( pxHeadListToMerge )->pxNext->pxPrev = ( pxHeadResultList );                    \
+            ( pxHeadResultList )->pxNext = ( pxHeadListToMerge )->pxNext;                    \
+            /* Empty the merged list. */                                                     \
+            listINIT_HEAD( ( pxHeadListToMerge ) );                                          \
+        }                                                                                    \
+    }
+
+/**
+ * @brief Helper macro to iterate over a list. pxLink contains the link node
+ * in each iteration.
+ */
+#define listFOR_EACH( pxLink, pxHead )    \
+    for( ( pxLink ) = ( pxHead )->pxNext; \
+         ( pxLink ) != ( pxHead );        \
+         ( pxLink ) = ( pxLink )->pxNext )
+
+/**
+ * @brief Helper macro to iterate over a list. It is safe to destroy/free the
+ * nodes while iterating. pxLink contains the link node in each iteration.
+ */
+#define listFOR_EACH_SAFE( pxLink, pxTempLink, pxHead )                        \
+    for( ( pxLink ) = ( pxHead )->pxNext, ( pxTempLink ) = ( pxLink )->pxNext; \
+         ( pxLink ) != ( pxHead );                                             \
+         ( pxLink ) = ( pxTempLink ), ( pxTempLink ) = ( pxLink )->pxNext )
+
+/**
+ * @brief Given the pointer to the link member (of type Link_t) in a struct,
+ * extracts the pointer to the containing struct.
+ *
+ * @param[in] pxLink The pointer to the link member.
+ * @param[in] type The type of the containing struct.
+ * @param[in] member Name of the link member in the containing struct.
+ */
+#define listCONTAINER( pxLink, type, member )    ( ( type * ) ( ( uint8_t * ) ( pxLink ) - ( uint8_t * ) ( &( ( type * ) 0 )->member ) ) )
+
+#endif /* _AWS_DOUBLY_LINKED_LIST_H_ */
diff --git a/makefile b/makefile
index e2c01c4..3e03b94 100644
--- a/makefile
+++ b/makefile
@@ -1,6 +1,6 @@
 # Target also determines which file is being compiled

-TARGET = master

-

+TARGET = master_rtos

+PORT   = posix

 

 ######################################

 # building variables

@@ -25,9 +25,16 @@ C_SOURCES =  \
 lib/nanopb/pb_decode.c \

 lib/nanopb/pb_encode.c \

 lib/nanopb/pb_common.c \

+lib/FreeRTOS/FreeRTOS/Source/tasks.c \

+lib/FreeRTOS/FreeRTOS/Source/list.c \

+lib/FreeRTOS/FreeRTOS/Source/queue.c \

+lib/FreeRTOS/FreeRTOS/Source/stream_buffer.c \

+lib/FreeRTOS/FreeRTOS/Source/timers.c \

+src/heap_4.c \

 src/handshake.pb.c \

 src/data.pb.c \

-src/stream_i2c.c

+src/master_posix.c \

+

 

 # set the main C source based on whether we're compiling the master or slave

 C_SOURCES+=$(addprefix src/, $(TARGET).c)

@@ -35,7 +42,7 @@ C_SOURCES+=$(addprefix src/, $(TARGET).c)
 #######################################

 # binaries

 #######################################

-PREFIX = arm-none-eabi-

+

 # The gcc compiler bin path can be either defined in make command via GCC_PATH variable (> make GCC_PATH=xxx)

 # either it can be added to the PATH environment variable.

 ifdef GCC_PATH

@@ -66,12 +73,12 @@ AS_INCLUDES =
 C_INCLUDES =  \

 -Iinclude \

 -Ilib/cmsis \

--Ilib/nanopb

-

+-Ilib/nanopb \

+-Ilib/FreeRTOS/FreeRTOS/Source/include/ \

 

 # Define the chip we're building for and include its makefile

-# Variable ASM_FILE will be defined in the included port makefile

-PORT     = stm32f4

+# Variables ASM_FILE, LDFLAGS, PREFIX will be defined in the included port makefile

+# Port-specific stream functions (ex. stream_i2c, stream_stdio) are included by the port makefile

 PORT_DIR = ports/$(PORT)

 include $(PORT_DIR)/makefile

 ASM_SOURCES=$(PORT_DIR)/$(ASM_FILE)

@@ -91,13 +98,10 @@ CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"
 #######################################

 # LDFLAGS

 #######################################

-# link script

-# LDSCRIPT = STM32F401CCUx_FLASH.ld

 

 # libraries

-LIBS = -lc -lm -lnosys 

+LIBS = -lc -lm -lpthread -lrt

 LIBDIR = 

-LDFLAGS = $(MCU) -specs=nosys.specs -specs=nano.specs -u _printf_float -T$(PORT_DIR)/$(LDSCRIPT) $(LIBDIR) $(LIBS) -Wl,-Map=$(BUILD_DIR)/$(TARGET).map,--cref -Wl,--gc-sections

 

 # default action: build all

 all: $(BUILD_DIR)/$(TARGET).elf $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin

diff --git a/ports/posix/makefile b/ports/posix/makefile
new file mode 100644
index 0000000..9031b76
--- /dev/null
+++ b/ports/posix/makefile
@@ -0,0 +1,12 @@
+
+
+PREFIX =
+
+LDFLAGS = $(LIBDIR) $(LIBS)
+
+C_INCLUDES += \
+-Ilib/FreeRTOS/FreeRTOS/Source/portable/ThirdParty/GCC/Posix/ \
+
+C_SOURCES += \
+lib/FreeRTOS/FreeRTOS/Source/portable/ThirdParty/GCC/Posix/port.c \
+ports/posix/src/stream_stdio.c
diff --git a/src/stream_stdio.c b/ports/posix/src/stream_stdio.c
index efa4b13..efa4b13 100644
--- a/src/stream_stdio.c
+++ b/ports/posix/src/stream_stdio.c
diff --git a/ports/stm32f4/makefile b/ports/stm32f4/makefile
index c3701b9..df447d1 100644
--- a/ports/stm32f4/makefile
+++ b/ports/stm32f4/makefile
@@ -1,11 +1,15 @@
 # Makefile for the STM32F4 port
 
+PREFIX = arm-none-eabi-
+
 # These variables are dependent on the target MCU
 LDSCRIPT=STM32F405RGTx_FLASH.ld
 ASM_FILE=startup_stm32f405xx.s
 C_DEFS += \
 -DSTM32F405xx
 
+LDFLAGS = $(MCU) -specs=nosys.specs -specs=nano.specs -u _printf_float -T$(PORT_DIR)/$(LDSCRIPT) $(LIBDIR) $(LIBS) -Wl,-Map=$(BUILD_DIR)/$(TARGET).map,--cref -Wl,--gc-sections
+
 FLOAT-ABI = -mfloat-abi=hard
 CPU = -mcpu=cortex-m4
 FPU = -mfpu=fpv4-sp-d16
@@ -34,6 +38,7 @@ lib/f4/stm32f4xx_hal_uart.c \
 ports/stm32f4/src/stm32f4xx_it.c \
 ports/stm32f4/src/stm32f4xx_hal_msp.c \
 ports/stm32f4/src/system_stm32f4xx.c \
+ports/stm32f4/src/stream_i2c.c
 
 C_INCLUDES += \
 -Ilib/f4 \
diff --git a/src/stream_i2c.c b/ports/stm32f4/src/stream_i2c.c
index b149756..3e8fc95 100644
--- a/src/stream_i2c.c
+++ b/ports/stm32f4/src/stream_i2c.c
@@ -5,7 +5,7 @@
 int i2c_read(uint8_t* buf, size_t count, void **vptr, void *sptr)
 {
     p_stream_t *stream = (p_stream_t*)sptr;
-    I2C_HandleTypeDef dev = *(I2C_HandleTypeDef*)stream->props[DEVICE];
+    I2C_HandleTypeDef dev = *(I2C_HandleTypeDef*)stream->props[0];
     
     uint16_t addr         = *(uint16_t*)vptr[0];
     uint32_t timeout      = *(uint32_t*)vptr[1];
@@ -26,7 +26,7 @@ int i2c_read(uint8_t* buf, size_t count, void **vptr, void *sptr)
 int i2c_write(uint8_t* buf, size_t count, void **vptr, void *sptr)
 {
     p_stream_t *stream = (p_stream_t*)sptr;
-    I2C_HandleTypeDef dev = *(I2C_HandleTypeDef*)stream->props[DEVICE];
+    I2C_HandleTypeDef dev = *(I2C_HandleTypeDef*)stream->props[0];
     uint16_t addr         = *(uint16_t*)vptr[1];
     uint32_t timeout      = *(uint32_t*)vptr[2];
     
diff --git a/src/heap_4.c b/src/heap_4.c
new file mode 100644
index 0000000..ade9e47
--- /dev/null
+++ b/src/heap_4.c
@@ -0,0 +1,492 @@
+/*

+ * FreeRTOS Kernel V10.3.1

+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.

+ *

+ * Permission is hereby granted, free of charge, to any person obtaining a copy of

+ * this software and associated documentation files (the "Software"), to deal in

+ * the Software without restriction, including without limitation the rights to

+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of

+ * the Software, and to permit persons to whom the Software is furnished to do so,

+ * subject to the following conditions:

+ *

+ * The above copyright notice and this permission notice shall be included in all

+ * copies or substantial portions of the Software.

+ *

+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS

+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR

+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER

+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

+ *

+ * http://www.FreeRTOS.org

+ * http://aws.amazon.com/freertos

+ *

+ * 1 tab == 4 spaces!

+ */

+

+/*

+ * A sample implementation of pvPortMalloc() and vPortFree() that combines

+ * (coalescences) adjacent memory blocks as they are freed, and in so doing

+ * limits memory fragmentation.

+ *

+ * See heap_1.c, heap_2.c and heap_3.c for alternative implementations, and the

+ * memory management pages of http://www.FreeRTOS.org for more information.

+ */

+#include <stdlib.h>

+

+/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining

+all the API functions to use the MPU wrappers.  That should only be done when

+task.h is included from an application file. */

+#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE

+

+#include "FreeRTOS.h"

+#include "task.h"

+

+#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE

+

+#if( configSUPPORT_DYNAMIC_ALLOCATION == 0 )

+	#error This file must not be used if configSUPPORT_DYNAMIC_ALLOCATION is 0

+#endif

+

+/* Block sizes must not get too small. */

+#define heapMINIMUM_BLOCK_SIZE	( ( size_t ) ( xHeapStructSize << 1 ) )

+

+/* Assumes 8bit bytes! */

+#define heapBITS_PER_BYTE		( ( size_t ) 8 )

+

+/* Allocate the memory for the heap. */

+#if( configAPPLICATION_ALLOCATED_HEAP == 1 )

+	/* The application writer has already defined the array used for the RTOS

+	heap - probably so it can be placed in a special segment or address. */

+	extern uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];

+#else

+	static uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];

+#endif /* configAPPLICATION_ALLOCATED_HEAP */

+

+/* Define the linked list structure.  This is used to link free blocks in order

+of their memory address. */

+typedef struct A_BLOCK_LINK

+{

+	struct A_BLOCK_LINK *pxNextFreeBlock;	/*<< The next free block in the list. */

+	size_t xBlockSize;						/*<< The size of the free block. */

+} BlockLink_t;

+

+/*-----------------------------------------------------------*/

+

+/*

+ * Inserts a block of memory that is being freed into the correct position in

+ * the list of free memory blocks.  The block being freed will be merged with

+ * the block in front it and/or the block behind it if the memory blocks are

+ * adjacent to each other.

+ */

+static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert );

+

+/*

+ * Called automatically to setup the required heap structures the first time

+ * pvPortMalloc() is called.

+ */

+static void prvHeapInit( void );

+

+/*-----------------------------------------------------------*/

+

+/* The size of the structure placed at the beginning of each allocated memory

+block must by correctly byte aligned. */

+static const size_t xHeapStructSize	= ( sizeof( BlockLink_t ) + ( ( size_t ) ( portBYTE_ALIGNMENT - 1 ) ) ) & ~( ( size_t ) portBYTE_ALIGNMENT_MASK );

+

+/* Create a couple of list links to mark the start and end of the list. */

+static BlockLink_t xStart, *pxEnd = NULL;

+

+/* Keeps track of the number of calls to allocate and free memory as well as the

+number of free bytes remaining, but says nothing about fragmentation. */

+static size_t xFreeBytesRemaining = 0U;

+static size_t xMinimumEverFreeBytesRemaining = 0U;

+static size_t xNumberOfSuccessfulAllocations = 0;

+static size_t xNumberOfSuccessfulFrees = 0;

+

+/* Gets set to the top bit of an size_t type.  When this bit in the xBlockSize

+member of an BlockLink_t structure is set then the block belongs to the

+application.  When the bit is free the block is still part of the free heap

+space. */

+static size_t xBlockAllocatedBit = 0;

+

+/*-----------------------------------------------------------*/

+

+void *pvPortMalloc( size_t xWantedSize )

+{

+BlockLink_t *pxBlock, *pxPreviousBlock, *pxNewBlockLink;

+void *pvReturn = NULL;

+

+	vTaskSuspendAll();

+	{

+		/* If this is the first call to malloc then the heap will require

+		initialisation to setup the list of free blocks. */

+		if( pxEnd == NULL )

+		{

+			prvHeapInit();

+		}

+		else

+		{

+			mtCOVERAGE_TEST_MARKER();

+		}

+

+		/* Check the requested block size is not so large that the top bit is

+		set.  The top bit of the block size member of the BlockLink_t structure

+		is used to determine who owns the block - the application or the

+		kernel, so it must be free. */

+		if( ( xWantedSize & xBlockAllocatedBit ) == 0 )

+		{

+			/* The wanted size is increased so it can contain a BlockLink_t

+			structure in addition to the requested amount of bytes. */

+			if( xWantedSize > 0 )

+			{

+				xWantedSize += xHeapStructSize;

+

+				/* Ensure that blocks are always aligned to the required number

+				of bytes. */

+				if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 )

+				{

+					/* Byte alignment required. */

+					xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) );

+					configASSERT( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) == 0 );

+				}

+				else

+				{

+					mtCOVERAGE_TEST_MARKER();

+				}

+			}

+			else

+			{

+				mtCOVERAGE_TEST_MARKER();

+			}

+

+			if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) )

+			{

+				/* Traverse the list from the start	(lowest address) block until

+				one	of adequate size is found. */

+				pxPreviousBlock = &xStart;

+				pxBlock = xStart.pxNextFreeBlock;

+				while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != NULL ) )

+				{

+					pxPreviousBlock = pxBlock;

+					pxBlock = pxBlock->pxNextFreeBlock;

+				}

+

+				/* If the end marker was reached then a block of adequate size

+				was	not found. */

+				if( pxBlock != pxEnd )

+				{

+					/* Return the memory space pointed to - jumping over the

+					BlockLink_t structure at its start. */

+					pvReturn = ( void * ) ( ( ( uint8_t * ) pxPreviousBlock->pxNextFreeBlock ) + xHeapStructSize );

+

+					/* This block is being returned for use so must be taken out

+					of the list of free blocks. */

+					pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock;

+

+					/* If the block is larger than required it can be split into

+					two. */

+					if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE )

+					{

+						/* This block is to be split into two.  Create a new

+						block following the number of bytes requested. The void

+						cast is used to prevent byte alignment warnings from the

+						compiler. */

+						pxNewBlockLink = ( void * ) ( ( ( uint8_t * ) pxBlock ) + xWantedSize );

+						configASSERT( ( ( ( size_t ) pxNewBlockLink ) & portBYTE_ALIGNMENT_MASK ) == 0 );

+

+						/* Calculate the sizes of two blocks split from the

+						single block. */

+						pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize;

+						pxBlock->xBlockSize = xWantedSize;

+

+						/* Insert the new block into the list of free blocks. */

+						prvInsertBlockIntoFreeList( pxNewBlockLink );

+					}

+					else

+					{

+						mtCOVERAGE_TEST_MARKER();

+					}

+

+					xFreeBytesRemaining -= pxBlock->xBlockSize;

+

+					if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining )

+					{

+						xMinimumEverFreeBytesRemaining = xFreeBytesRemaining;

+					}

+					else

+					{

+						mtCOVERAGE_TEST_MARKER();

+					}

+

+					/* The block is being returned - it is allocated and owned

+					by the application and has no "next" block. */

+					pxBlock->xBlockSize |= xBlockAllocatedBit;

+					pxBlock->pxNextFreeBlock = NULL;

+					xNumberOfSuccessfulAllocations++;

+				}

+				else

+				{

+					mtCOVERAGE_TEST_MARKER();

+				}

+			}

+			else

+			{

+				mtCOVERAGE_TEST_MARKER();

+			}

+		}

+		else

+		{

+			mtCOVERAGE_TEST_MARKER();

+		}

+

+		traceMALLOC( pvReturn, xWantedSize );

+	}

+	( void ) xTaskResumeAll();

+

+	#if( configUSE_MALLOC_FAILED_HOOK == 1 )

+	{

+		if( pvReturn == NULL )

+		{

+			extern void vApplicationMallocFailedHook( void );

+			vApplicationMallocFailedHook();

+		}

+		else

+		{

+			mtCOVERAGE_TEST_MARKER();

+		}

+	}

+	#endif

+

+	configASSERT( ( ( ( size_t ) pvReturn ) & ( size_t ) portBYTE_ALIGNMENT_MASK ) == 0 );

+	return pvReturn;

+}

+/*-----------------------------------------------------------*/

+

+void vPortFree( void *pv )

+{

+uint8_t *puc = ( uint8_t * ) pv;

+BlockLink_t *pxLink;

+

+	if( pv != NULL )

+	{

+		/* The memory being freed will have an BlockLink_t structure immediately

+		before it. */

+		puc -= xHeapStructSize;

+

+		/* This casting is to keep the compiler from issuing warnings. */

+		pxLink = ( void * ) puc;

+

+		/* Check the block is actually allocated. */

+		configASSERT( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 );

+		configASSERT( pxLink->pxNextFreeBlock == NULL );

+

+		if( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 )

+		{

+			if( pxLink->pxNextFreeBlock == NULL )

+			{

+				/* The block is being returned to the heap - it is no longer

+				allocated. */

+				pxLink->xBlockSize &= ~xBlockAllocatedBit;

+

+				vTaskSuspendAll();

+				{

+					/* Add this block to the list of free blocks. */

+					xFreeBytesRemaining += pxLink->xBlockSize;

+					traceFREE( pv, pxLink->xBlockSize );

+					prvInsertBlockIntoFreeList( ( ( BlockLink_t * ) pxLink ) );

+					xNumberOfSuccessfulFrees++;

+				}

+				( void ) xTaskResumeAll();

+			}

+			else

+			{

+				mtCOVERAGE_TEST_MARKER();

+			}

+		}

+		else

+		{

+			mtCOVERAGE_TEST_MARKER();

+		}

+	}

+}

+/*-----------------------------------------------------------*/

+

+size_t xPortGetFreeHeapSize( void )

+{

+	return xFreeBytesRemaining;

+}

+/*-----------------------------------------------------------*/

+

+size_t xPortGetMinimumEverFreeHeapSize( void )

+{

+	return xMinimumEverFreeBytesRemaining;

+}

+/*-----------------------------------------------------------*/

+

+void vPortInitialiseBlocks( void )

+{

+	/* This just exists to keep the linker quiet. */

+}

+/*-----------------------------------------------------------*/

+

+static void prvHeapInit( void )

+{

+BlockLink_t *pxFirstFreeBlock;

+uint8_t *pucAlignedHeap;

+size_t uxAddress;

+size_t xTotalHeapSize = configTOTAL_HEAP_SIZE;

+

+	/* Ensure the heap starts on a correctly aligned boundary. */

+	uxAddress = ( size_t ) ucHeap;

+

+	if( ( uxAddress & portBYTE_ALIGNMENT_MASK ) != 0 )

+	{

+		uxAddress += ( portBYTE_ALIGNMENT - 1 );

+		uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK );

+		xTotalHeapSize -= uxAddress - ( size_t ) ucHeap;

+	}

+

+	pucAlignedHeap = ( uint8_t * ) uxAddress;

+

+	/* xStart is used to hold a pointer to the first item in the list of free

+	blocks.  The void cast is used to prevent compiler warnings. */

+	xStart.pxNextFreeBlock = ( void * ) pucAlignedHeap;

+	xStart.xBlockSize = ( size_t ) 0;

+

+	/* pxEnd is used to mark the end of the list of free blocks and is inserted

+	at the end of the heap space. */

+	uxAddress = ( ( size_t ) pucAlignedHeap ) + xTotalHeapSize;

+	uxAddress -= xHeapStructSize;

+	uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK );

+	pxEnd = ( void * ) uxAddress;

+	pxEnd->xBlockSize = 0;

+	pxEnd->pxNextFreeBlock = NULL;

+

+	/* To start with there is a single free block that is sized to take up the

+	entire heap space, minus the space taken by pxEnd. */

+	pxFirstFreeBlock = ( void * ) pucAlignedHeap;

+	pxFirstFreeBlock->xBlockSize = uxAddress - ( size_t ) pxFirstFreeBlock;

+	pxFirstFreeBlock->pxNextFreeBlock = pxEnd;

+

+	/* Only one block exists - and it covers the entire usable heap space. */

+	xMinimumEverFreeBytesRemaining = pxFirstFreeBlock->xBlockSize;

+	xFreeBytesRemaining = pxFirstFreeBlock->xBlockSize;

+

+	/* Work out the position of the top bit in a size_t variable. */

+	xBlockAllocatedBit = ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 );

+}

+/*-----------------------------------------------------------*/

+

+static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert )

+{

+BlockLink_t *pxIterator;

+uint8_t *puc;

+

+	/* Iterate through the list until a block is found that has a higher address

+	than the block being inserted. */

+	for( pxIterator = &xStart; pxIterator->pxNextFreeBlock < pxBlockToInsert; pxIterator = pxIterator->pxNextFreeBlock )

+	{

+		/* Nothing to do here, just iterate to the right position. */

+	}

+

+	/* Do the block being inserted, and the block it is being inserted after

+	make a contiguous block of memory? */

+	puc = ( uint8_t * ) pxIterator;

+	if( ( puc + pxIterator->xBlockSize ) == ( uint8_t * ) pxBlockToInsert )

+	{

+		pxIterator->xBlockSize += pxBlockToInsert->xBlockSize;

+		pxBlockToInsert = pxIterator;

+	}

+	else

+	{

+		mtCOVERAGE_TEST_MARKER();

+	}

+

+	/* Do the block being inserted, and the block it is being inserted before

+	make a contiguous block of memory? */

+	puc = ( uint8_t * ) pxBlockToInsert;

+	if( ( puc + pxBlockToInsert->xBlockSize ) == ( uint8_t * ) pxIterator->pxNextFreeBlock )

+	{

+		if( pxIterator->pxNextFreeBlock != pxEnd )

+		{

+			/* Form one big block from the two blocks. */

+			pxBlockToInsert->xBlockSize += pxIterator->pxNextFreeBlock->xBlockSize;

+			pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock->pxNextFreeBlock;

+		}

+		else

+		{

+			pxBlockToInsert->pxNextFreeBlock = pxEnd;

+		}

+	}

+	else

+	{

+		pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock;

+	}

+

+	/* If the block being inserted plugged a gab, so was merged with the block

+	before and the block after, then it's pxNextFreeBlock pointer will have

+	already been set, and should not be set here as that would make it point

+	to itself. */

+	if( pxIterator != pxBlockToInsert )

+	{

+		pxIterator->pxNextFreeBlock = pxBlockToInsert;

+	}

+	else

+	{

+		mtCOVERAGE_TEST_MARKER();

+	}

+}

+/*-----------------------------------------------------------*/

+

+void vPortGetHeapStats( HeapStats_t *pxHeapStats )

+{

+BlockLink_t *pxBlock;

+size_t xBlocks = 0, xMaxSize = 0, xMinSize = portMAX_DELAY; /* portMAX_DELAY used as a portable way of getting the maximum value. */

+

+	vTaskSuspendAll();

+	{

+		pxBlock = xStart.pxNextFreeBlock;

+

+		/* pxBlock will be NULL if the heap has not been initialised.  The heap

+		is initialised automatically when the first allocation is made. */

+		if( pxBlock != NULL )

+		{

+			do

+			{

+				/* Increment the number of blocks and record the largest block seen

+				so far. */

+				xBlocks++;

+

+				if( pxBlock->xBlockSize > xMaxSize )

+				{

+					xMaxSize = pxBlock->xBlockSize;

+				}

+

+				if( pxBlock->xBlockSize < xMinSize )

+				{

+					xMinSize = pxBlock->xBlockSize;

+				}

+

+				/* Move to the next block in the chain until the last block is

+				reached. */

+				pxBlock = pxBlock->pxNextFreeBlock;

+			} while( pxBlock != pxEnd );

+		}

+	}

+	( void ) xTaskResumeAll();

+

+	pxHeapStats->xSizeOfLargestFreeBlockInBytes = xMaxSize;

+	pxHeapStats->xSizeOfSmallestFreeBlockInBytes = xMinSize;

+	pxHeapStats->xNumberOfFreeBlocks = xBlocks;

+

+	taskENTER_CRITICAL();

+	{

+		pxHeapStats->xAvailableHeapSpaceInBytes = xFreeBytesRemaining;

+		pxHeapStats->xNumberOfSuccessfulAllocations = xNumberOfSuccessfulAllocations;

+		pxHeapStats->xNumberOfSuccessfulFrees = xNumberOfSuccessfulFrees;

+		pxHeapStats->xMinimumEverFreeBytesRemaining = xMinimumEverFreeBytesRemaining;

+	}

+	taskEXIT_CRITICAL();

+}

+

diff --git a/src/master_posix.c b/src/master_posix.c
new file mode 100644
index 0000000..355960d
--- /dev/null
+++ b/src/master_posix.c
@@ -0,0 +1,315 @@
+
+/* 
+ * TODO Do conditional includes based on which target we are building for.
+ *   This should be specified in the master config file
+ * TODO This file should be moved to the posix port folder
+*/
+
+/* FreeRTOS includes. */
+/* #include "FreeRTOS_POSIX.h" */
+
+/* System headers. */
+#include <stdbool.h>
+#include <string.h>
+#include <stdio.h>
+
+/* Demo includes. */
+/* #include "posix_demo.h" */
+
+/* FreeRTOS+POSIX. */
+/* #include "FreeRTOS_POSIX/pthread.h" */
+/* #include "FreeRTOS_POSIX/mqueue.h" */
+/* #include "FreeRTOS_POSIX/time.h" */
+/* #include "FreeRTOS_POSIX/fcntl.h" */
+/* #include "FreeRTOS_POSIX/errno.h" */
+
+#include <pthread.h>
+#include <mqueue.h>
+#include <stdint.h>
+#include <errno.h>
+/* Constants. */
+#define LINE_BREAK    "\r\n"
+
+/**
+ * @brief Control messages.
+ *
+ * uint8_t is sufficient for this enum, that we are going to cast to char directly.
+ * If ever needed, implement a function to properly typecast.
+ */
+/**@{ */
+typedef enum ControlMessage
+{
+    eMSG_LOWER_INAVLID = 0x00,        /**< Guard, let's not use 0x00 for messages. */
+    eWORKER_CTRL_MSG_CONTINUE = 0x01, /**< Dispatcher to worker, distributing another job. */
+    eWORKER_CTRL_MSG_EXIT = 0x02,     /**< Dispatcher to worker, all jobs are finished and the worker receiving such can exit. */
+
+    /* define additional messages here */
+
+    eMSG_UPPER_INVALID = 0xFF /**< Guard, additional tasks shall be defined above. */
+} eControlMessage;
+/**@} */
+
+/**
+ * @defgroup Configuration constants for the dispatcher-worker demo.
+ */
+/**@{ */
+#define MQUEUE_NUMBER_OF_WORKERS    ( 2 )                        /**< The number of worker threads, each thread has one queue which is used as income box. */
+
+#if ( MQUEUE_NUMBER_OF_WORKERS > 10 )
+#error "Please keep MQUEUE_NUMBER_OF_WORKERS < 10."
+#endif
+
+#define MQUEUE_WORKER_QNAME_BASE                "/qNode0"         /**< Queue name base. */
+#define MQUEUE_WORKER_QNAME_BASE_LEN            ( 6 )             /** Queue name base length. */
+
+#define MQUEUE_TIMEOUT_SECONDS                  ( 1 )             /**< Relative timeout for mqueue functions. */
+#define MQUEUE_MAX_NUMBER_OF_MESSAGES_WORKER    ( 1 )             /**< Maximum number of messages in a queue. */
+
+#define MQUEUE_MSG_WORKER_CTRL_MSG_SIZE         sizeof( uint8_t ) /**< Control message size. */
+#define DEMO_ERROR                              ( -1 )            /**< Any non-zero value would work. */
+/**@} */
+
+/**
+ * @brief Structure used by Worker thread.
+ */
+/**@{ */
+typedef struct WorkerThreadResources
+{
+    pthread_t pxID; /**< thread ID. */
+    mqd_t xInboxID; /**< mqueue inbox ID. */
+} WorkerThreadResources_t;
+/**@} */
+
+/**
+ * @brief Structure used by Dispatcher thread.
+ */
+/**@{ */
+typedef struct DispatcherThreadResources
+{
+    pthread_t pxID;    /**< thread ID. */
+    mqd_t * pOutboxID; /**< a list of mqueue outbox ID. */
+} DispatcherThreadResources_t;
+/**@} */
+
+/*-----------------------------------------------------------*/
+
+static void * prvWorkerThread( void * pvArgs )
+{
+    WorkerThreadResources_t pArgList = *( WorkerThreadResources_t * ) pvArgs;
+
+    printf( "Worker thread #[%d] - start %s", ( int ) pArgList.pxID, LINE_BREAK );
+
+    struct timespec xReceiveTimeout = { 0 };
+
+    ssize_t xMessageSize = 0;
+    char pcReceiveBuffer[ MQUEUE_MSG_WORKER_CTRL_MSG_SIZE ] = { 0 };
+
+    /* This is a worker thread that reacts based on what is sent to its inbox (mqueue). */
+    while( true )
+    {
+        clock_gettime( CLOCK_REALTIME, &xReceiveTimeout );
+        xReceiveTimeout.tv_sec += MQUEUE_TIMEOUT_SECONDS;
+
+        xMessageSize = mq_receive( pArgList.xInboxID,
+                                   pcReceiveBuffer,
+                                   MQUEUE_MSG_WORKER_CTRL_MSG_SIZE,
+                                   0 );
+
+        /* Parse messages */
+        if( xMessageSize == MQUEUE_MSG_WORKER_CTRL_MSG_SIZE )
+        {
+            switch( ( int ) pcReceiveBuffer[ 0 ] )
+            {
+	    case eWORKER_CTRL_MSG_CONTINUE:
+		/* Task branch, currently only prints message to screen. */
+		/* Could perform tasks here. Could also notify dispatcher upon completion, if desired. */
+		printf( "Worker thread #[%d] -- Received eWORKER_CTRL_MSG_CONTINUE %s", ( int ) pArgList.pxID, LINE_BREAK );
+		break;
+
+	    case eWORKER_CTRL_MSG_EXIT:
+		printf( "Worker thread #[%d] -- Finished. Exit now. %s", ( int ) pArgList.pxID, LINE_BREAK );
+
+		return NULL;
+
+	    default:
+		/* Received a message that we don't care or not defined. */
+		break;
+            }
+        }
+        else
+        {
+            /* Invalid message. Error handling can be done here, if desired. */
+        }
+    }
+
+    /* You should never hit here. */
+    /* return NULL; */
+}
+
+/*-----------------------------------------------------------*/
+
+static void * prvDispatcherThread( void * pvArgs )
+{
+    DispatcherThreadResources_t pArgList = *( DispatcherThreadResources_t * ) pvArgs;
+
+    printf( "Dispatcher thread - start %s", LINE_BREAK );
+
+    struct timespec xSendTimeout = { 0 };
+
+    ssize_t xMessageSize = 0;
+    char pcSendBuffer[ MQUEUE_MSG_WORKER_CTRL_MSG_SIZE ] = { 0 };
+
+    /* Just for fun, let threads do a total of 100 independent tasks. */
+    int i = 0;
+    const int totalNumOfJobsPerThread = 100;
+
+    /* Distribute 1000 independent tasks to workers, in round-robin fashion. */
+    pcSendBuffer[ 0 ] = ( char ) eWORKER_CTRL_MSG_CONTINUE;
+
+    for( i = 0; i < totalNumOfJobsPerThread; i++ )
+    {
+        clock_gettime( CLOCK_REALTIME, &xSendTimeout );
+        xSendTimeout.tv_sec += MQUEUE_TIMEOUT_SECONDS;
+
+        printf( "Dispatcher iteration #[%d] -- Sending msg to worker thread #[%d]. %s", i, ( int ) pArgList.pOutboxID[ i % MQUEUE_NUMBER_OF_WORKERS ], LINE_BREAK );
+
+        xMessageSize = mq_timedsend( pArgList.pOutboxID[ i % MQUEUE_NUMBER_OF_WORKERS ],
+                                     pcSendBuffer,
+                                     MQUEUE_MSG_WORKER_CTRL_MSG_SIZE,
+                                     0,
+                                     &xSendTimeout );
+
+        if( xMessageSize != 0 )
+        {
+            /* This error is acceptable in our setup.
+             * Since inbox for each thread fits only one message.
+             * In reality, balance inbox size, message arrival rate, and message drop rate. */
+            printf( "An acceptable failure -- dispatcher failed to send eWORKER_CTRL_MSG_CONTINUE to outbox ID: %x. errno %d %s",
+                    ( int ) pArgList.pOutboxID[ i % MQUEUE_NUMBER_OF_WORKERS ], errno, LINE_BREAK );
+        }
+    }
+
+    /* Control thread is now done with distributing jobs. Tell workers they are done. */
+    pcSendBuffer[ 0 ] = ( char ) eWORKER_CTRL_MSG_EXIT;
+
+    for( i = 0; i < MQUEUE_NUMBER_OF_WORKERS; i++ )
+    {
+        printf( "Dispatcher [%d] -- Sending eWORKER_CTRL_MSG_EXIT to worker thread #[%d]. %s", i, ( int ) pArgList.pOutboxID[ i % MQUEUE_NUMBER_OF_WORKERS ], LINE_BREAK );
+
+        /* This is a blocking call, to guarantee worker thread exits. */
+        xMessageSize = mq_send( pArgList.pOutboxID[ i % MQUEUE_NUMBER_OF_WORKERS ],
+                                pcSendBuffer,
+                                MQUEUE_MSG_WORKER_CTRL_MSG_SIZE,
+                                0 );
+    }
+
+    return NULL;
+}
+
+/*-----------------------------------------------------------*/
+
+/**
+ * @brief Job distribution with actor model.
+ *
+ * See the top of this file for detailed description.
+ */
+void vStartPOSIXMaster()
+{
+    int i = 0;
+    int iStatus = 0;
+
+    /* Remove warnings about unused parameters. */
+
+    /* Handles of the threads and related resources. */
+    DispatcherThreadResources_t pxDispatcher = { 0 };
+    WorkerThreadResources_t pxWorkers[ MQUEUE_NUMBER_OF_WORKERS ] = { { 0 } };
+    mqd_t workerMqueues[ MQUEUE_NUMBER_OF_WORKERS ] = { 0 };
+
+    struct mq_attr xQueueAttributesWorker =
+	{
+	    .mq_flags   = 0,
+	    .mq_maxmsg  = MQUEUE_MAX_NUMBER_OF_MESSAGES_WORKER,
+	    .mq_msgsize = MQUEUE_MSG_WORKER_CTRL_MSG_SIZE,
+	    .mq_curmsgs = 0
+	};
+
+    pxDispatcher.pOutboxID = workerMqueues;
+
+    /* Create message queues for each worker thread. */
+    for( i = 0; i < MQUEUE_NUMBER_OF_WORKERS; i++ )
+    {
+        /* Prepare a unique queue name for each worker. */
+        char qName[] = MQUEUE_WORKER_QNAME_BASE;
+        qName[ MQUEUE_WORKER_QNAME_BASE_LEN - 1 ] = qName[ MQUEUE_WORKER_QNAME_BASE_LEN - 1 ] + i;
+
+        /* Open a queue with --
+         * O_CREAT -- create a message queue.
+         * O_RDWR -- both receiving and sending messages.
+         */
+        pxWorkers[ i ].xInboxID = mq_open( qName,
+                                           O_CREAT | O_RDWR,
+                                           ( mode_t ) 0,
+                                           &xQueueAttributesWorker );
+
+        if( pxWorkers[ i ].xInboxID == ( mqd_t ) -1 )
+        {
+            printf( "Invalid inbox (mqueue) for worker. %s", LINE_BREAK );
+            iStatus = DEMO_ERROR;
+            break;
+        }
+
+        /* Outboxes of dispatcher thread is the inboxes of all worker threads. */
+        pxDispatcher.pOutboxID[ i ] = pxWorkers[ i ].xInboxID;
+    }
+
+    /* Create and start Worker threads. */
+    if( iStatus == 0 )
+    {
+        for( i = 0; i < MQUEUE_NUMBER_OF_WORKERS; i++ )
+        {
+            ( void ) pthread_create( &( pxWorkers[ i ].pxID ), NULL, prvWorkerThread, &pxWorkers[ i ] );
+        }
+
+        /* Create and start dispatcher thread. */
+        ( void ) pthread_create( &( pxDispatcher.pxID ), NULL, prvDispatcherThread, &pxDispatcher );
+
+        /* Actors will do predefined tasks in threads. Current implementation is that
+         * dispatcher actor notifies worker actors to terminate upon finishing distributing tasks. */
+
+        /* Wait for worker threads to join. */
+        for( i = 0; i < MQUEUE_NUMBER_OF_WORKERS; i++ )
+        {
+            ( void ) pthread_join( pxWorkers[ i ].pxID, NULL );
+        }
+
+        /* Wait for dispatcher thread to join. */
+        ( void ) pthread_join( pxDispatcher.pxID, NULL );
+    }
+
+    /* Close and unlink worker message queues. */
+    for( i = 0; i < MQUEUE_NUMBER_OF_WORKERS; i++ )
+    {
+        char qName[] = MQUEUE_WORKER_QNAME_BASE;
+        qName[ MQUEUE_WORKER_QNAME_BASE_LEN - 1 ] = qName[ MQUEUE_WORKER_QNAME_BASE_LEN - 1 ] + i;
+
+        if( pxWorkers[ i ].xInboxID != NULL )
+        {
+            ( void ) mq_close( pxWorkers[ i ].xInboxID );
+            ( void ) mq_unlink( qName );
+        }
+    }
+
+    /* Have something on console. */
+    if( iStatus == 0 )
+    {
+        printf( "All threads finished. %s", LINE_BREAK );
+    }
+    else
+    {
+        printf( "Queues did not get initialized properly. Did not run demo. %s", LINE_BREAK );
+    }
+
+    /* This task was created with the native xTaskCreate() API function, so
+       must not run off the end of its implementing thread. */
+    /* vTaskDelete( NULL ); */
+}
diff --git a/src/master_rtos.c b/src/master_rtos.c
new file mode 100644
index 0000000..4ca3461
--- /dev/null
+++ b/src/master_rtos.c
@@ -0,0 +1,147 @@
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+
+/* System headers */
+#include <stdio.h>
+
+/* Master include */
+#include "master_posix.h"
+
+/* Master task priority */
+#define mainPOSIX_MASTER_PRIORITY    (tskIDLE_PRIORITY + 4)
+ 
+int main(void)
+{
+    configASSERT((mainPOSIX_MASTER_PRIORITY < configMAX_PRIORITIES));
+
+    /* const uint32_t ulLongTime_ms = pdMS_TO_TICKS(1000UL); */
+
+    /* Start the task to run POSIX Master */
+    xTaskCreate(vStartPOSIXMaster,
+                "posix",
+                configMINIMAL_STACK_SIZE,
+                NULL,
+                mainPOSIX_MASTER_PRIORITY,
+		NULL);
+
+    vTaskStartScheduler();
+
+    /* If all is well, the scheduler will now be running, and the following
+     * line will never be reached.  If the following line does execute, then
+     * there was insufficient FreeRTOS heap memory available for the idle and/or
+     * timer tasks to be created.
+     */
+    for(; ;)
+    {
+        /* Sleep(ulLongTime_ms); */
+    }
+
+    return 0;
+}
+
+
+/*-----------------------------------------------------------*/
+
+void vAssertCalled(const char * pcFile,
+                   uint32_t ulLine)
+{
+    /* const uint32_t ulLongSleep = 1000UL; */
+    volatile uint32_t ulBlockVariable = 0UL;
+    volatile char * pcFileName = ( volatile char * ) pcFile;
+    volatile uint32_t ulLineNumber = ulLine;
+
+    (void) pcFileName;
+    (void) ulLineNumber;
+
+    printf("vAssertCalled %s, %ld\n", pcFile, (long) ulLine);
+    fflush(stdout);
+
+    /* Setting ulBlockVariable to a non-zero value in the debugger will allow
+     * this function to be exited. */
+    taskDISABLE_INTERRUPTS();
+    {
+        while(ulBlockVariable == 0UL)
+        {
+            /* Sleep(ulLongSleep); */
+        }
+    }
+    taskENABLE_INTERRUPTS();
+}
+
+/*-----------------------------------------------------------*/
+
+/* configUSE_STATIC_ALLOCATION is set to 1, so the application must provide an
+ * implementation of vApplicationGetIdleTaskMemory() to provide the memory that is
+ * used by the Idle task. */
+void vApplicationGetIdleTaskMemory(StaticTask_t ** ppxIdleTaskTCBBuffer,
+                                   StackType_t ** ppxIdleTaskStackBuffer,
+                                   uint32_t * pulIdleTaskStackSize)
+{
+    /* If the buffers to be provided to the Idle task are declared inside this
+     * function then they must be declared static - otherwise they will be allocated on
+     * the stack and so not exists after this function exits. */
+    static StaticTask_t xIdleTaskTCB;
+    static StackType_t uxIdleTaskStack[ configMINIMAL_STACK_SIZE ];
+
+    /* Pass out a pointer to the StaticTask_t structure in which the Idle
+     * task's state will be stored. */
+    *ppxIdleTaskTCBBuffer = &xIdleTaskTCB;
+
+    /* Pass out the array that will be used as the Idle task's stack. */
+    *ppxIdleTaskStackBuffer = uxIdleTaskStack;
+
+    /* Pass out the size of the array pointed to by *ppxIdleTaskStackBuffer.
+     * Note that, as the array is necessarily of type StackType_t,
+     * configMINIMAL_STACK_SIZE is specified in words, not bytes. */
+    *pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;
+}
+
+/*-----------------------------------------------------------*/
+
+/* configUSE_STATIC_ALLOCATION and configUSE_TIMERS are both set to 1, so the
+ * application must provide an implementation of vApplicationGetTimerTaskMemory()
+ * to provide the memory that is used by the Timer service task. */
+void vApplicationGetTimerTaskMemory(StaticTask_t ** ppxTimerTaskTCBBuffer,
+                                    StackType_t ** ppxTimerTaskStackBuffer,
+                                    uint32_t * pulTimerTaskStackSize)
+{
+    /* If the buffers to be provided to the Timer task are declared inside this
+     * function then they must be declared static - otherwise they will be allocated on
+     * the stack and so not exists after this function exits. */
+    static StaticTask_t xTimerTaskTCB;
+    static StackType_t uxTimerTaskStack[ configTIMER_TASK_STACK_DEPTH ];
+
+    /* Pass out a pointer to the StaticTask_t structure in which the Timer
+     * task's state will be stored. */
+    *ppxTimerTaskTCBBuffer = &xTimerTaskTCB;
+
+    /* Pass out the array that will be used as the Timer task's stack. */
+    *ppxTimerTaskStackBuffer = uxTimerTaskStack;
+
+    /* Pass out the size of the array pointed to by *ppxTimerTaskStackBuffer.
+     * Note that, as the array is necessarily of type StackType_t,
+     * configTIMER_TASK_STACK_DEPTH is specified in words, not bytes. */
+    *pulTimerTaskStackSize = configTIMER_TASK_STACK_DEPTH;
+}
+
+/*-----------------------------------------------------------*/
+
+/**
+ * @brief Warn user if pvPortMalloc fails.
+ *
+ * Called if a call to pvPortMalloc() fails because there is insufficient
+ * free memory available in the FreeRTOS heap.  pvPortMalloc() is called
+ * internally by FreeRTOS API functions that create tasks, queues, software
+ * timers, and semaphores.  The size of the FreeRTOS heap is set by the
+ * configTOTAL_HEAP_SIZE configuration constant in FreeRTOSConfig.h.
+ *
+ */
+void vApplicationMallocFailedHook()
+{
+    taskDISABLE_INTERRUPTS();
+
+    for(;;)
+    {
+    }
+}