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#include <_ansi.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <mips/hal.h>
extern char _end[];
/* FIXME: This is not ideal, since we do a get_ram_range() call for
every sbrk() call. */
char *
sbrk (int nbytes)
{
static char *heap_ptr = NULL;
static char *heap_start = NULL;
static unsigned long heap_size = 0;
char *base;
ptrdiff_t avail = 0;
void *ram_base;
void *ram_extent;
if (heap_start == NULL)
{
_get_ram_range (&ram_base, &ram_extent);
/* If the _end symbol is within the RAM then use _end. */
if ((void*)_end > ram_base && (void*)_end < ram_extent)
{
heap_start = _end;
heap_ptr = _end;
heap_size = ram_extent - (void*)_end;
}
else
{
heap_start = ram_base;
heap_ptr = ram_base;
heap_size = ram_extent - ram_base;
}
}
if ((heap_ptr >= heap_start) &&
(heap_ptr < (heap_start + heap_size))) {
avail = (heap_start + heap_size) - heap_ptr;
base = heap_ptr;
} /* else will fail since "nbytes" will be greater than zeroed "avail" value */
if ((nbytes > avail) || (heap_ptr + nbytes < heap_start))
base = (char *)-1;
else
heap_ptr += nbytes;
return base;
}
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