1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*
28 *	Copyright (c) 1988 AT&T
29 *	  All Rights Reserved
30 */
31
32#include <sys/mman.h>
33#include <stdio.h>
34#include <stdlib.h>
35#include <unistd.h>
36#include <libelf.h>
37#include <errno.h>
38#include "decl.h"
39#include "msg.h"
40
41/*
42 * File output
43 *	These functions write output files.
44 *	On SVR4 and newer systems use mmap(2).  On older systems (or on
45 *	file systems that don't support mmap), use write(2).
46 */
47
48
49char *
50_elf_outmap(int fd, size_t sz, unsigned int *pflag)
51{
52	char	*p;
53
54	/*
55	 * Note: Some NFS implementations do not provide from enlarging a file
56	 * via ftruncate(), thus this may fail with ENOSUP.  In this case the
57	 * fall through to the calloc() mechanism will occur.
58	 */
59	if ((!*pflag) && (ftruncate(fd, (off_t)sz) == 0) &&
60	    (p = mmap((char *)0, sz, PROT_READ+PROT_WRITE,
61	    MAP_SHARED, fd, (off_t)0)) != (char *)-1) {
62		*pflag = 1;
63		return (p);
64	}
65
66	*pflag = 0;
67
68	/*
69	 * If mmap fails, try calloc.  Some file systems don't mmap.  Note, we
70	 * use calloc rather than malloc, as ld(1) assumes that the backing
71	 * storage it is working with is zero filled.
72	 */
73	if ((p = (char *)calloc(1, sz)) == 0)
74		_elf_seterr(EMEM_OUT, errno);
75	return (p);
76}
77
78
79size_t
80_elf_outsync(int fd, char *p, size_t sz, unsigned int flag)
81{
82	if (flag != 0) {
83		int	err;
84
85		if ((fd = msync(p, sz, MS_ASYNC)) == -1)
86			err = errno;
87		(void) munmap(p, sz);
88		if (fd == 0)
89			return (sz);
90		_elf_seterr(EIO_SYNC, err);
91		return (0);
92	}
93	if ((lseek(fd, 0L, SEEK_SET) == 0) &&
94	    (write(fd, p, sz) == sz)) {
95		(void) free(p);
96		return (sz);
97	}
98	_elf_seterr(EIO_WRITE, errno);
99	return (0);
100}
101