blob: 53efe1e844fc79262fa428cc0f6133a31e2db8cd (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
#include <reent.h>
#include <errno.h>
#include <stdlib.h>
#include <FreeRTOS.h>
#include <task.h>
#include <semphr.h>
#include <mpu_wrappers.h>
#include "osdebug.h"
// Mostly stolen from mbed-freertos
extern uintptr_t __heap_start;
extern uintptr_t __stack_start;
/* Low-level bulk RAM allocator -- used by Newlib's Malloc */
static void *heap_end = (void *) &__heap_start;
static xSemaphoreHandle sbrk_sem = NULL;
__attribute__((constructor)) static void sbrk_init() {
sbrk_sem = xSemaphoreCreateMutex();
}
void *_sbrk_r(struct _reent *ptr, ptrdiff_t incr) {
void *prev_heap_end, *next_heap_end, *ret;
void *stack_min = (void *) &__stack_start;
if (sbrk_sem)
xSemaphoreTake(sbrk_sem, portMAX_DELAY);
prev_heap_end = heap_end;
/* Align to always be on 8-byte boundaries */
next_heap_end = (void *)((((uintptr_t)heap_end + incr) + 7) & ~7);
/* Check if this allocation would exceed the end of the ram - would probably get into the stack first however */
if (next_heap_end > stack_min) {
ptr->_errno = ENOMEM;
ret = NULL;
} else {
heap_end = next_heap_end;
ret = (void *)prev_heap_end;
}
if (sbrk_sem)
xSemaphoreGive(sbrk_sem);
return ret;
}
|