Add function sail_set_coverage_file to sail_coverage header

Can be set by C emulator to control where coverage information is
written

4 files changed, 25 insertions, 15 deletions

diff --git a/lib/coverage/src/lib.rs b/lib/coverage/src/lib.rs
index 003f8b88..34261eae 100644
--- a/lib/coverage/src/lib.rs
+++ b/lib/coverage/src/lib.rs
@@ -3,7 +3,7 @@ use lazy_static::lazy_static;
 
 use std::collections::HashSet;
 use std::ffi::{CStr, CString};
-use std::fs::{OpenOptions, File};
+use std::fs::{File, OpenOptions};
 use std::io::Write;
 use std::os::raw::{c_char, c_int};
 use std::sync::Mutex;
@@ -20,6 +20,7 @@ struct Span {
 lazy_static! {
     static ref BRANCHES: Mutex<HashSet<Span>> = Mutex::new(HashSet::new());
     static ref FUNCTIONS: Mutex<HashSet<Span>> = Mutex::new(HashSet::new());
+    static ref OUTPUT_FILE: Mutex<String> = Mutex::new("sail_coverage".to_string());
 }
 
 fn function_entry(_function_name: &CStr, span: Span) {
@@ -30,15 +31,13 @@ fn branch_taken(_branch_id: i32, span: Span) {
     BRANCHES.lock().unwrap().insert(span);
 }
 
-fn branch_reached(_branch_id: i32, _span: Span) {
-    ()
-}
+fn branch_reached(_branch_id: i32, _span: Span) {}
 
 fn write_locations(file: &mut File, kind: char, spans: &Mutex<HashSet<Span>>) -> bool {
     for span in spans.lock().unwrap().iter() {
-        let res = write!(
+        let res = writeln!(
             file,
-            "{} \"{}\", {}, {}, {}, {}\n",
+            "{} \"{}\", {}, {}, {}, {}",
             kind,
             span.sail_file.to_string_lossy(),
             span.line1,
@@ -49,18 +48,22 @@ fn write_locations(file: &mut File, kind: char, spans: &Mutex<HashSet<Span>>) ->
         if res.is_err() {
             return false;
         }
-    };
+    }
     true
 }
 
 #[no_mangle]
 pub extern "C" fn sail_coverage_exit() -> c_int {
-    if let Ok(mut file) = OpenOptions::new().create(true).append(true).open("sail_coverage") {
+    if let Ok(mut file) = OpenOptions::new()
+        .create(true)
+        .append(true)
+        .open(&*OUTPUT_FILE.lock().unwrap())
+    {
         if !write_locations(&mut file, 'B', &BRANCHES) {
-            return 1
+            return 1;
         }
         if !write_locations(&mut file, 'F', &FUNCTIONS) {
-            return 1
+            return 1;
         }
         0
     } else {
@@ -69,6 +72,11 @@ pub extern "C" fn sail_coverage_exit() -> c_int {
 }
 
 #[no_mangle]
+pub unsafe extern "C" fn sail_set_coverage_file(output_file: *const c_char) {
+    *OUTPUT_FILE.lock().unwrap() = CStr::from_ptr(output_file).to_string_lossy().to_string()
+}
+
+#[no_mangle]
 pub unsafe extern "C" fn sail_function_entry(
     function_name: *const c_char,
     sail_file: *const c_char,
diff --git a/lib/sail_coverage.h b/lib/sail_coverage.h
index 92f78f9c..487b9dce 100644
--- a/lib/sail_coverage.h
+++ b/lib/sail_coverage.h
@@ -3,10 +3,12 @@
 
 int sail_coverage_exit(void);
 
-void sail_function_entry(char *function_name, char *sail_file, int l1, int c1, int l2, int c2);
+void sail_set_coverage_file(const char *output_file);
 
-void sail_branch_taken(int branch_id, char *sail_file, int l1, int c1, int l2, int c2);
+void sail_function_entry(const char *function_name, const char *sail_file, int l1, int c1, int l2, int c2);
 
-void sail_branch_reached(int branch_id, char *sail_file, int l1, int c1, int l2, int c2);
+void sail_branch_taken(int branch_id, const char *sail_file, int l1, int c1, int l2, int c2);
+
+void sail_branch_reached(int branch_id, const char *sail_file, int l1, int c1, int l2, int c2);
 
 #endif
diff --git a/src/jib/c_backend.mli b/src/jib/c_backend.mli
index 5f2d5211..2d3d3c2b 100644
--- a/src/jib/c_backend.mli
+++ b/src/jib/c_backend.mli
@@ -89,7 +89,7 @@ val opt_extra_params : string option ref
 val opt_extra_arguments : string option ref
 
 val opt_branch_coverage : out_channel option ref
-  
+ 
 (** Optimization flags *)
 
 val optimize_primops : bool ref
diff --git a/src/sail.ml b/src/sail.ml
index 31fc7717..d07ea216 100644
--- a/src/sail.ml
+++ b/src/sail.ml
@@ -234,7 +234,7 @@ let options = Arg.align ([
     " remove comma separated list of functions from C output, replacing them with unit");
   ( "-c_coverage",
     Arg.String (fun str -> C_backend.opt_branch_coverage := Some (open_out str)),
-    " output file for C code instrumention to track branch coverage");
+    "<file> Turn on coverage tracking and output information about all branches and functions to a file");
   ( "-elf",
     Arg.String (fun elf -> opt_process_elf := Some elf),
     " process an ELF file so that it can be executed by compiled C code");