[deliverable/binutils-gdb.git] / gold / mremap.c

/* mremap.c -- version of mremap for gold.  */

/* Copyright (C) 2009-2020 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) */
Commit	Line	Data
2f35ab9b ILT	1	/* mremap.c -- version of mremap for gold. */
2f35ab9b ILT	2
b3adc24a	3	/* Copyright (C) 2009-2020 Free Software Foundation, Inc.
2f35ab9b ILT	4	Written by Ian Lance Taylor <iant@google.com>.
	5
	6	This file is part of gold.
	7
	8	This program is free software; you can redistribute it and/or modify
	9	it under the terms of the GNU General Public License as published by
	10	the Free Software Foundation; either version 3 of the License, or
	11	(at your option) any later version.
	12
	13	This program is distributed in the hope that it will be useful,
	14	but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	GNU General Public License for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with this program; if not, write to the Free Software
	20	Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
	21	MA 02110-1301, USA. */
	22
	23	#include "config.h"
	24	#include "ansidecl.h"
	25
88597d34	26	#include <errno.h>
2f35ab9b ILT	27	#include <string.h>
2f35ab9b ILT	28	#include <sys/types.h>
88597d34 ILT	29
88597d34 ILT	30	#ifdef HAVE_SYS_MMAN_H
2f35ab9b	31	#include <sys/mman.h>
88597d34 ILT	32	#endif
	33
	34	extern void gold_mremap (void , size_t, size_t, int);
	35
	36	#ifdef HAVE_MMAP
2f35ab9b ILT	37
	38	/* This file implements mremap for systems which don't have it. The
	39	gold code requires support for mmap. However, there are systems
	40	which have mmap but not mremap. This is not a general replacement
	41	for mremap; it only supports the features which are required for
	42	gold. In particular, we assume that the MREMAP_MAYMOVE flag is
	43	set. */
	44
	45	/* Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS. */
	46
	47	#ifndef MAP_ANONYMOUS
	48	# define MAP_ANONYMOUS MAP_ANON
	49	#endif
	50
	51	void *
88597d34 ILT	52	gold_mremap (void *old_address, size_t old_size, size_t new_size,
88597d34 ILT	53	int flags ATTRIBUTE_UNUSED)
2f35ab9b ILT	54	{
	55	void *ret;
	56
	57	ret = mmap (0, new_size, PROT_READ \| PROT_WRITE,
	58	MAP_PRIVATE \| MAP_ANONYMOUS, -1, 0);
	59	if (ret == MAP_FAILED)
	60	return ret;
	61	memcpy (ret, old_address,
	62	old_size < new_size ? old_size : new_size);
	63	(void) munmap (old_address, old_size);
	64	return ret;
	65	}
88597d34 ILT	66
	67	#else /* !defined(HAVE_MMAP) */
	68
	69	#ifndef MAP_FAILED
	70	#define MAP_FAILED ((void *) -1)
	71	#endif
	72
	73	#ifndef ENOSYS
	74	#define ENOSYS EINVAL
	75	#endif
	76
	77	void *
	78	gold_mremap (void *old_address ATTRIBUTE_UNUSED,
	79	size_t old_size ATTRIBUTE_UNUSED,
	80	size_t new_size ATTRIBUTE_UNUSED,
	81	int flags ATTRIBUTE_UNUSED)
	82	{
	83	errno = ENOSYS;
	84	return MAP_FAILED;
	85	}
	86
	87	#endif /* !defined(HAVE_MMAP) */