newlib/libgloss/moxie/sbrk.c
Jeff Johnston bc6b90cc10 2009-04-22 Anthony Green <green@moxielogic.com>
* configure.in: Add moxie support.
        * configure: Regenerate.
        * moxie/aclocal.m4, moxie/configure, moxie/configure.in,
        moxie/crt0.S, moxie/fstat.c, moxie/getpid.c, isatty.c,
        moxie/kill.c, moxie/Makefile.in, moxie/moxie-elf-common.ld,
        moxie/print.c, moxie/putnum.c, moxie/qemu.ld, moxie/qemu-time.c,
        moxie/qemu-write.c, moxie/sbrk.c, moxie/sim-close.S,
        moxie/sim-exit.S,
        moxie/sim-inbyte.c, moxie/sim.ld, moxie/sim-lseek.c,
        moxie/sim-lseek.S, moxie/sim-open.S, moxie/sim-read.S, moxie/sim-time.c,
        moxie/sim-unlink.S, moxie/sim-write.S, moxie/stat.c: New files.
2009-04-22 19:48:07 +00:00

55 lines
1.4 KiB
C

/* sbrk.c -- allocate memory dynamically.
*
* Copyright (c) 2008 Anthony Green
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice is included verbatim in any distributions. No written agreement,
* license, or royalty fee is required for any of the authorized uses.
* Modifications to this software may be copyrighted by their authors
* and need not follow the licensing terms described here, provided that
* the new terms are clearly indicated on the first page of each file where
* they apply.
*/
#include <errno.h>
#include "glue.h"
/* just in case, most boards have at least some memory */
#ifndef RAMSIZE
# define RAMSIZE (caddr_t)0x100000
#endif
char *__heap_ptr = (char *)&_end;
/*
* sbrk -- changes heap size size. Get nbytes more
* RAM. We just increment a pointer in what's
* left of memory on the board.
*/
char *
_sbrk (nbytes)
int nbytes;
{
char *base;
char *sp;
base = __heap_ptr;
__heap_ptr += nbytes;
return base;
/* FIXME: We really want to make sure we don't run out of RAM, but this
* isn't very portable.
*/
#if 0
if ((RAMSIZE - heap_ptr - nbytes) >= 0) {
base = heap_ptr;
heap_ptr += nbytes;
return (base);
} else {
errno = ENOMEM;
return ((char *)-1);
}
#endif
}