xref: /titanic_41/usr/src/cmd/sgs/libelf/common/error.c (revision c94146ce6d2a316eca6450a8cd77d8dee993f233)
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 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI" 	/* SVr4.0 1.16	*/
28 
29 
30 #pragma weak	elf_errmsg = _elf_errmsg
31 #pragma weak	elf_errno = _elf_errno
32 
33 #include "syn.h"
34 #include <thread.h>
35 #include <pthread.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <stdio.h>
39 #include <libelf.h>
40 #include "msg.h"
41 #include "decl.h"
42 
43 #define	ELFERRSHIFT	16
44 #define	SYSERRMASK	0xffff
45 
46 
47 /*
48  * _elf_err has two values encoded in it, both the _elf_err # and
49  * the system errno value (if relevant).  These values are encoded
50  * in the upper & lower 16 bits of the 4 byte integer.
51  */
52 static int		_elf_err = 0;
53 
54 #if !defined(NATIVE_BUILD)
55 
56 static thread_key_t	errkey = THR_ONCE_KEY;
57 static thread_key_t	bufkey = THR_ONCE_KEY;
58 
59 #else	/* NATIVE_BUILD */
60 
61 /*
62  * This code is here to enable the building of a native version
63  * of libelf.so when the build machine has not yet been upgraded
64  * to a version of libc that provides thr_keycreate_once().
65  * It should be deleted when solaris_nevada ships.
66  * The code is not MT-safe in a relaxed memory model.
67  */
68 
69 static thread_key_t	errkey = 0;
70 static thread_key_t	bufkey = 0;
71 
72 int
73 thr_keycreate_once(thread_key_t *keyp, void (*destructor)(void *))
74 {
75 	static mutex_t key_lock = DEFAULTMUTEX;
76 	thread_key_t key;
77 	int error;
78 
79 	if (*keyp == 0) {
80 		mutex_lock(&key_lock);
81 		if (*keyp == 0) {
82 			error = thr_keycreate(&key, destructor);
83 			if (error) {
84 				mutex_unlock(&key_lock);
85 				return (error);
86 			}
87 			*keyp = key;
88 		}
89 		mutex_unlock(&key_lock);
90 	}
91 
92 	return (0);
93 }
94 
95 #endif	/* NATIVE_BUILD */
96 
97 extern char *_dgettext(const char *, const char *);
98 
99 
100 const char *
101 _libelf_msg(Msg mid)
102 {
103 	return (_dgettext(MSG_ORIG(MSG_SUNW_OST_SGS), MSG_ORIG(mid)));
104 }
105 
106 
107 void
108 _elf_seterr(Msg lib_err, int sys_err)
109 {
110 	/*LINTED*/
111 	intptr_t encerr = ((int)lib_err << ELFERRSHIFT) |
112 	    (sys_err & SYSERRMASK);
113 
114 #ifndef	__lock_lint
115 	if (thr_main()) {
116 		_elf_err = (int)encerr;
117 		return;
118 	}
119 #endif
120 	(void) thr_keycreate_once(&errkey, 0);
121 	(void) thr_setspecific(errkey, (void *)encerr);
122 }
123 
124 int
125 _elf_geterr() {
126 #ifndef	__lock_lint
127 	if (thr_main())
128 		return (_elf_err);
129 #endif
130 	return ((uintptr_t)pthread_getspecific(errkey));
131 }
132 
133 const char *
134 elf_errmsg(int err)
135 {
136 	char			*errno_str;
137 	char			*elferr_str;
138 	char			*buffer = 0;
139 	int			syserr;
140 	int			elferr;
141 	static char		intbuf[MAXELFERR];
142 
143 	if (err == 0) {
144 		if ((err = _elf_geterr()) == 0)
145 			return (0);
146 	} else if (err == -1) {
147 		if ((err = _elf_geterr()) == 0)
148 			/*LINTED*/ /* MSG_INTL(EINF_NULLERROR) */
149 			err = (int)EINF_NULLERROR << ELFERRSHIFT;
150 	}
151 
152 	if (thr_main())
153 		buffer = intbuf;
154 	else {
155 		/*
156 		 * If this is a threaded APP then we store the
157 		 * errmsg buffer in Thread Specific Storage.
158 		 *
159 		 * Each thread has its own private buffer.
160 		 */
161 		if (thr_keycreate_once(&bufkey, free) != 0)
162 			return (MSG_INTL(EBUG_THRDKEY));
163 		buffer = pthread_getspecific(bufkey);
164 
165 		if (!buffer) {
166 			if ((buffer = malloc(MAXELFERR)) == 0)
167 				return (MSG_INTL(EMEM_ERRMSG));
168 			if (thr_setspecific(bufkey, buffer) != 0) {
169 				free(buffer);
170 				return (MSG_INTL(EBUG_THRDSET));
171 			}
172 		}
173 	}
174 
175 	elferr = (int)((uint_t)err >> ELFERRSHIFT);
176 	syserr = err & SYSERRMASK;
177 	/*LINTED*/
178 	elferr_str = (char *)MSG_INTL(elferr);
179 	if (syserr && (errno_str = strerror(syserr)))
180 		(void) snprintf(buffer, MAXELFERR,
181 		    MSG_ORIG(MSG_FMT_ERR), elferr_str, errno_str);
182 	else {
183 		(void) strncpy(buffer, elferr_str, MAXELFERR - 1);
184 		buffer[MAXELFERR - 1] = '\0';
185 	}
186 
187 	return (buffer);
188 }
189 
190 int
191 elf_errno()
192 {
193 	int	rc = _elf_geterr();
194 
195 	_elf_seterr(0, 0);
196 	return (rc);
197 }
198