ack/plat/msdos386/libsys/sbrk.c

41 lines
567 B
C

/* $Source$
* $State$
* $Revision$
*/
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include "libsys.h"
extern char _end[1];
static char* current = _end;
void* sbrk(int increment)
{
char* old;
char* new;
if (increment == 0)
return current;
old = current;
new = old + increment;
if ((increment > 0) && (new <= old))
goto out_of_memory;
else if ((increment < 0) && (new >= old))
goto out_of_memory;
if (brk(new) < 0)
goto out_of_memory;
current = new;
return old;
out_of_memory:
errno = ENOMEM;
return OUT_OF_MEMORY;
}