git: 9front

ref: 33bdd7e6c2bbfc7e2373b4e8d0371fd89dc31e52
dir: /sys/src/ape/lib/ap/plan9/brk.c/

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#include "lib.h"
#include <errno.h>
#include <stdint.h>
#include "sys9.h"

char	end[];
static	char	*bloc = { end };
extern	int	_BRK_(void*);

char *
brk(char *p)
{
	unsigned long n;

	n = (uintptr_t)p;
	n += 3;
	n &= ~3;
	if(_BRK_((void*)n) < 0){
		errno = ENOMEM;
		return (char *)-1;
	}
	bloc = (char *)n;
	return 0;
}

void *
sbrk(unsigned long n)
{
	n += 3;
	n &= ~3;
	if(_BRK_((void *)(bloc+n)) < 0){
		errno = ENOMEM;
		return (void *)-1;
	}
	bloc += n;
	return (void *)(bloc-n);
}