common/misc.c


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#include <common.h>
#include <mem_malloc.h>

/*
 * Begin and End of memory area for malloc(), and current "brk"
 */
static ulong mem_malloc_start = 0;
static ulong mem_malloc_end = 0;
static ulong mem_malloc_brk = 0;

void mem_malloc_init (ulong start, ulong end)
{
	mem_malloc_start = start;
	mem_malloc_end = end;
	mem_malloc_brk = mem_malloc_start;

	memset ((void *) mem_malloc_start, 0,
			mem_malloc_end - mem_malloc_start);
}

void *sbrk (ptrdiff_t increment)
{
	ulong old = mem_malloc_brk;
	ulong new = old + increment;

	if ((new < mem_malloc_start) || (new > mem_malloc_end)) {
		return (NULL);
	}
	mem_malloc_brk = new;

	return ((void *) old);
}