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 2008 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#pragma ident	"@(#)output.c	1.21	08/05/31 SMI"
33
34#include <sys/mman.h>
35#include <stdio.h>
36#include <stdlib.h>
37#include <unistd.h>
38#include <libelf.h>
39#include <errno.h>
40#include "decl.h"
41#include "msg.h"
42
43/*
44 * File output
45 *	These functions write output files.
46 *	On SVR4 and newer systems use mmap(2).  On older systems (or on
47 *	file systems that don't support mmap), use write(2).
48 */
49
50
51char *
52_elf_outmap(int fd, size_t sz, unsigned int *pflag)
53{
54	char	*p;
55
56	/*
57	 * Note: Some NFS implementations do not provide from enlarging a file
58	 * via ftruncate(), thus this may fail with ENOSUP.  In this case the
59	 * fall through to the calloc() mechanism will occur.
60	 */
61	if ((!*pflag) && (ftruncate(fd, (off_t)sz) == 0) &&
62	    (p = mmap((char *)0, sz, PROT_READ+PROT_WRITE,
63	    MAP_SHARED, fd, (off_t)0)) != (char *)-1) {
64		*pflag = 1;
65		return (p);
66	}
67
68	*pflag = 0;
69
70	/*
71	 * If mmap fails, try calloc.  Some file systems don't mmap.  Note, we
72	 * use calloc rather than malloc, as ld(1) assumes that the backing
73	 * storage it is working with is zero filled.
74	 */
75	if ((p = (char *)calloc(1, sz)) == 0)
76		_elf_seterr(EMEM_OUT, errno);
77	return (p);
78}
79
80
81size_t
82_elf_outsync(int fd, char *p, size_t sz, unsigned int flag)
83{
84	if (flag != 0) {
85		int	err;
86		/*
87		 * The value of MS_SYNC changed from zero to non-zero
88		 * in SunOS 5.7.  This double call covers both cases.
89		 */
90		if ((fd = msync(p, sz, MS_SYNC)) == -1)
91			fd = msync(p, sz, 0);
92		if (fd == -1)
93			err = errno;
94		(void) munmap(p, sz);
95		if (fd == 0)
96			return (sz);
97		_elf_seterr(EIO_SYNC, err);
98		return (0);
99	}
100	if ((lseek(fd, 0L, SEEK_SET) == 0) &&
101	    (write(fd, p, sz) == sz) && (fsync(fd) == 0)) {
102		(void) free(p);
103		return (sz);
104	}
105	_elf_seterr(EIO_WRITE, errno);
106	return (0);
107}
108