sbrk.c

DC的SEGA_GG模拟器源代码

/* donated by dcgrendel */
char *get_stack_ptr(void);
__asm__("
_get_stack_ptr:
	mov	r15, r0
	mov	#0, r1
	rts
	nop
");


void *sbrk(int incr)
{
	extern char end;
	static char *heap_end;
	char *prev_heap_end;
	char *stack_ptr = get_stack_ptr();

	if (heap_end == 0) {
		heap_end = &end;
		heap_end = (char *)(((int)heap_end & 0xffffffe0) + 0x20);
	}

	prev_heap_end = heap_end;

	if (heap_end + incr > stack_ptr)
	{
                (*(void(**)())0x8c0000e0)(1);
	}

	heap_end += incr;
	return(prev_heap_end);
}