rt-thread-official/bsp/imxrt/libraries/MIMXRT1020/MIMXRT1021/utilities/fsl_sbrk.c

54 lines
1.1 KiB
C

/*
* Copyright (c) 2015, Freescale Semiconductor, Inc.
* Copyright 2016-2019 NXP
* All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#if defined(__GNUC__)
#include <stdio.h>
#include <errno.h>
#endif
#if defined(__GNUC__)
/*!
* @brief Function to override ARMGCC default function _sbrk
*
* _sbrk is called by malloc. ARMGCC default _sbrk compares "SP" register and
* heap end, if heap end is larger than "SP", then _sbrk returns error and
* memory allocation failed. This function changes to compare __HeapLimit with
* heap end.
*/
caddr_t _sbrk(int incr);
caddr_t _sbrk(int incr)
{
extern char end __asm("end");
extern char heap_limit __asm("__HeapLimit");
static char *heap_end;
char *prev_heap_end;
caddr_t ret;
if (heap_end == NULL)
{
heap_end = &end;
}
prev_heap_end = heap_end;
if ((unsigned int)heap_end + (unsigned int)incr > (unsigned int)(&heap_limit))
{
errno = ENOMEM;
ret = (caddr_t)-1;
}
else
{
heap_end = (char *)((unsigned int)heap_end + (unsigned int)incr);
ret = (caddr_t)prev_heap_end;
}
return ret;
}
#endif