binutils-gdb/gold/mremap.c

88 lines
2.4 KiB
C

/* mremap.c -- version of mremap for gold. */
/* Copyright (C) 2009-2021 Free Software Foundation, Inc.
Written by Ian Lance Taylor <iant@google.com>.
This file is part of gold.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include "config.h"
#include "ansidecl.h"
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
extern void *gold_mremap (void *, size_t, size_t, int);
#ifdef HAVE_MMAP
/* This file implements mremap for systems which don't have it. The
gold code requires support for mmap. However, there are systems
which have mmap but not mremap. This is not a general replacement
for mremap; it only supports the features which are required for
gold. In particular, we assume that the MREMAP_MAYMOVE flag is
set. */
/* Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS. */
#ifndef MAP_ANONYMOUS
# define MAP_ANONYMOUS MAP_ANON
#endif
void *
gold_mremap (void *old_address, size_t old_size, size_t new_size,
int flags ATTRIBUTE_UNUSED)
{
void *ret;
ret = mmap (0, new_size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (ret == MAP_FAILED)
return ret;
memcpy (ret, old_address,
old_size < new_size ? old_size : new_size);
(void) munmap (old_address, old_size);
return ret;
}
#else /* !defined(HAVE_MMAP) */
#ifndef MAP_FAILED
#define MAP_FAILED ((void *) -1)
#endif
#ifndef ENOSYS
#define ENOSYS EINVAL
#endif
void *
gold_mremap (void *old_address ATTRIBUTE_UNUSED,
size_t old_size ATTRIBUTE_UNUSED,
size_t new_size ATTRIBUTE_UNUSED,
int flags ATTRIBUTE_UNUSED)
{
errno = ENOSYS;
return MAP_FAILED;
}
#endif /* !defined(HAVE_MMAP) */