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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2021 Damien P. George
*
* 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.
*/
#include <string.h>
// These memory functions are needed when the garbage collector is disabled.
// A full implementation should be provided, or the garbage collector enabled.
// The functions here are very simple.
extern char _heap_start;
void *malloc(size_t n) {
static char *cur_heap = NULL;
if (cur_heap == NULL) {
cur_heap = &_heap_start;
}
void *ptr = cur_heap;
cur_heap += (n + 7) & ~7;
return ptr;
}
void *realloc(void *ptr, size_t size) {
void *ptr2 = malloc(size);
if (ptr && size) {
memcpy(ptr2, ptr, size); // size may be greater than ptr's region, do copy anyway
}
return ptr2;
}
void free(void *p) {
}
// These standard string functions are needed by the runtime, and can be
// provided either by the system or lib/libc/string0.c. The implementations
// here are very simple.
int memcmp(const void *s1, const void *s2, size_t n) {
const unsigned char *ss1 = s1, *ss2 = s2;
while (n--) {
int c = *ss1++ - *ss2++;
if (c) {
return c;
}
}
return 0;
}
void *memcpy(void *dest, const void *src, size_t n) {
return memmove(dest, src, n);
}
void *memmove(void *dest, const void *src, size_t n) {
unsigned char *d = dest;
const unsigned char *s = src;
if (s < d && d < s + n) {
// Need to copy backwards.
d += n - 1;
s += n - 1;
while (n--) {
*d-- = *s--;
}
} else {
// Can copy forwards.
while (n--) {
*d++ = *s++;
}
}
return dest;
}
void *memset(void *s, int c, size_t n) {
unsigned char *ss = s;
while (n--) {
*ss++ = c;
}
return s;
}
char *strchr(const char *s, int c) {
while (*s) {
if (*s == c) {
return (char *)s;
}
++s;
}
return NULL;
}
int strcmp(const char *s1, const char *s2) {
while (*s1 && *s2) {
int c = *s1++ - *s2++;
if (c) {
return c;
}
}
return *s1 - *s2;
}
size_t strlen(const char *s) {
const char *ss = s;
while (*ss) {
++ss;
}
return ss - s;
}
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