xref: /onnv-gate/usr/src/cmd/sgs/libelf/common/output.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
23*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate 
26*0Sstevel@tonic-gate /*
27*0Sstevel@tonic-gate  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28*0Sstevel@tonic-gate  * Use is subject to license terms.
29*0Sstevel@tonic-gate  */
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI" 	/* SVr4.0 1.3	*/
33*0Sstevel@tonic-gate 
34*0Sstevel@tonic-gate #include "syn.h"
35*0Sstevel@tonic-gate #include <sys/mman.h>
36*0Sstevel@tonic-gate #include <stdio.h>
37*0Sstevel@tonic-gate #include <stdlib.h>
38*0Sstevel@tonic-gate #include <unistd.h>
39*0Sstevel@tonic-gate #include <libelf.h>
40*0Sstevel@tonic-gate #include <errno.h>
41*0Sstevel@tonic-gate #include "decl.h"
42*0Sstevel@tonic-gate #include "msg.h"
43*0Sstevel@tonic-gate 
44*0Sstevel@tonic-gate /*
45*0Sstevel@tonic-gate  * File output
46*0Sstevel@tonic-gate  *	These functions write output files.
47*0Sstevel@tonic-gate  *	On SVR4 and newer systems use mmap(2).  On older systems (or on
48*0Sstevel@tonic-gate  *	file systems that don't support mmap), use write(2).
49*0Sstevel@tonic-gate  */
50*0Sstevel@tonic-gate 
51*0Sstevel@tonic-gate 
52*0Sstevel@tonic-gate char *
53*0Sstevel@tonic-gate _elf_outmap(int fd, size_t sz, unsigned int *pflag)
54*0Sstevel@tonic-gate {
55*0Sstevel@tonic-gate 	char	*p;
56*0Sstevel@tonic-gate 
57*0Sstevel@tonic-gate 	/*
58*0Sstevel@tonic-gate 	 * Note: Some NFS implementations do not provide from enlarging a file
59*0Sstevel@tonic-gate 	 * via ftruncate(), thus this may fail with ENOSUP.  In this case the
60*0Sstevel@tonic-gate 	 * fall through to the calloc() mechanism will occur.
61*0Sstevel@tonic-gate 	 */
62*0Sstevel@tonic-gate 	if ((!*pflag) && (ftruncate(fd, (off_t)sz) == 0) &&
63*0Sstevel@tonic-gate 	    (p = mmap((char *)0, sz, PROT_READ+PROT_WRITE,
64*0Sstevel@tonic-gate 	    MAP_SHARED, fd, (off_t)0)) != (char *)-1) {
65*0Sstevel@tonic-gate 		*pflag = 1;
66*0Sstevel@tonic-gate 		return (p);
67*0Sstevel@tonic-gate 	}
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate 	*pflag = 0;
70*0Sstevel@tonic-gate 
71*0Sstevel@tonic-gate 	/*
72*0Sstevel@tonic-gate 	 * If mmap fails, try calloc.  Some file systems don't mmap.  Note, we
73*0Sstevel@tonic-gate 	 * use calloc rather than malloc, as ld(1) assumes that the backing
74*0Sstevel@tonic-gate 	 * storage it is working with is zero filled.
75*0Sstevel@tonic-gate 	 */
76*0Sstevel@tonic-gate 	if ((p = (char *)calloc(1, sz)) == 0)
77*0Sstevel@tonic-gate 		_elf_seterr(EMEM_OUT, errno);
78*0Sstevel@tonic-gate 	return (p);
79*0Sstevel@tonic-gate }
80*0Sstevel@tonic-gate 
81*0Sstevel@tonic-gate 
82*0Sstevel@tonic-gate size_t
83*0Sstevel@tonic-gate _elf_outsync(int fd, char *p, size_t sz, unsigned int flag)
84*0Sstevel@tonic-gate {
85*0Sstevel@tonic-gate 	if (flag != 0) {
86*0Sstevel@tonic-gate 		int	err;
87*0Sstevel@tonic-gate 		/*
88*0Sstevel@tonic-gate 		 * The value of MS_SYNC changed from zero to non-zero
89*0Sstevel@tonic-gate 		 * in SunOS 5.7.  This double call covers both cases.
90*0Sstevel@tonic-gate 		 */
91*0Sstevel@tonic-gate 		if ((fd = msync(p, sz, MS_SYNC)) == -1)
92*0Sstevel@tonic-gate 			fd = msync(p, sz, 0);
93*0Sstevel@tonic-gate 		if (fd == -1)
94*0Sstevel@tonic-gate 			err = errno;
95*0Sstevel@tonic-gate 		(void) munmap(p, sz);
96*0Sstevel@tonic-gate 		if (fd == 0)
97*0Sstevel@tonic-gate 			return (sz);
98*0Sstevel@tonic-gate 		_elf_seterr(EIO_SYNC, err);
99*0Sstevel@tonic-gate 		return (0);
100*0Sstevel@tonic-gate 	}
101*0Sstevel@tonic-gate 	if (lseek(fd, 0L, SEEK_SET) == 0) {
102*0Sstevel@tonic-gate 		if (write(fd, p, sz) == sz) {
103*0Sstevel@tonic-gate 			(void) free(p);
104*0Sstevel@tonic-gate 			return (sz);
105*0Sstevel@tonic-gate 		}
106*0Sstevel@tonic-gate 	}
107*0Sstevel@tonic-gate 	_elf_seterr(EIO_WRITE, errno);
108*0Sstevel@tonic-gate 	return (0);
109*0Sstevel@tonic-gate }
110