shlib.c revision 1.8 
1/*	$OpenBSD: shlib.c,v 1.8 2003/07/06 20:04:00 deraadt Exp $	*/
2/*	$NetBSD: shlib.c,v 1.13 1998/04/04 01:00:29 fvdl Exp $	*/
3
4/*
5 * Copyright (c) 1993 Paul Kranenburg
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by Paul Kranenburg.
19 * 4. The name of the author may not be used to endorse or promote products
20 *    derived from this software without specific prior written permission
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 *
33 */
34
35#include <sys/param.h>
36#include <sys/types.h>
37#include <sys/stat.h>
38#include <sys/file.h>
39#include <sys/time.h>
40#include <ranlib.h>
41#include <a.out.h>
42#include <ctype.h>
43#include <dirent.h>
44#include <err.h>
45#include <fcntl.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49
50#include "ld.h"
51
52/*
53 * Standard directories to search for files specified by -l.
54 */
55#ifndef STANDARD_SEARCH_DIRS
56#define	STANDARD_SEARCH_DIRS	"/usr/lib"
57#endif
58
59/*
60 * Actual vector of library search directories,
61 * including `-L'ed and LD_LIBRARY_PATH spec'd ones.
62 */
63char	 **search_dirs;
64int	n_search_dirs;
65
66char	*standard_search_dirs[] = {
67	STANDARD_SEARCH_DIRS
68};
69
70void
71add_search_dir(char *name)
72{
73	int i, len;
74
75	len = strlen(name);
76
77	while (len > 1 && name[len - 1] == '/')
78		--len;
79
80	for (i = 0; i < n_search_dirs; i++)
81		if (strlen(search_dirs[i]) == len &&
82		    !strncmp(search_dirs[i], name, len))
83				return;
84	n_search_dirs++;
85	search_dirs = (char **)
86	    xrealloc(search_dirs, n_search_dirs * sizeof search_dirs[0]);
87	search_dirs[n_search_dirs - 1] = xmalloc(++len);
88	(void)strlcpy(search_dirs[n_search_dirs - 1], name, len);
89}
90
91void
92remove_search_dir(char *name)
93{
94	int	i, len;
95
96	len = strlen(name);
97
98	while (len > 1 && name[len - 1] == '/')
99		--len;
100
101	for (i = 0; i < n_search_dirs; i++) {
102		if (strlen(search_dirs[i]) != len ||
103		    strncmp(search_dirs[i], name, len))
104			continue;
105		free(search_dirs[i]);
106		if (i < (n_search_dirs - 1))
107			bcopy(&search_dirs[i+1], &search_dirs[i],
108			    (n_search_dirs - i - 1) * sizeof search_dirs[0]);
109		n_search_dirs--;
110		search_dirs = (char **)xrealloc(search_dirs,
111		    n_search_dirs * sizeof search_dirs[0]);
112		break;
113	}
114}
115
116void
117add_search_path(char *path)
118{
119	char	*cp, *dup;
120
121	if (path == NULL)
122		return;
123
124	/* Add search directories from `path' */
125	path = dup = strdup(path);
126	while ((cp = strsep(&path, ":")) != NULL)
127		add_search_dir(cp);
128	free(dup);
129}
130
131static void
132remove_search_path(char *path)
133{
134	char	*cp, *dup;
135
136	if (path == NULL)
137		return;
138
139	/* Remove search directories from `path' */
140	path = dup = strdup(path);
141	while ((cp = strsep(&path, ":")) != NULL)
142		remove_search_dir(cp);
143	free(dup);
144}
145
146void
147std_search_path(void)
148{
149	int	i, n;
150
151	/* Append standard search directories */
152	n = sizeof standard_search_dirs / sizeof standard_search_dirs[0];
153	for (i = 0; i < n; i++)
154		add_search_dir(standard_search_dirs[i]);
155}
156
157/*
158 * Return true if CP points to a valid dewey number.
159 * Decode and leave the result in the array DEWEY.
160 * Return the number of decoded entries in DEWEY.
161 */
162
163int
164getdewey(int dewey[], char *cp)
165{
166	int	i, n;
167
168	for (n = 0, i = 0; i < MAXDEWEY; i++) {
169		if (*cp == '\0')
170			break;
171
172		if (*cp == '.') cp++;
173#ifdef SUNOS_LIB_COMPAT
174		if (!(isdigit)(*cp))
175#else
176		if (!isdigit(*cp))
177#endif
178			return 0;
179
180		dewey[n++] = strtol(cp, &cp, 10);
181	}
182	return n;
183}
184
185/*
186 * Compare two dewey arrays.
187 * Return -1 if `d1' represents a smaller value than `d2'.
188 * Return  1 if `d1' represents a greater value than `d2'.
189 * Return  0 if equal.
190 */
191int
192cmpndewey(int d1[], int n1, int d2[], int n2)
193{
194	int	i;
195
196	for (i = 0; i < n1 && i < n2; i++) {
197		if (d1[i] < d2[i])
198			return -1;
199		if (d1[i] > d2[i])
200			return 1;
201	}
202	if (n1 == n2)
203		return 0;
204	if (i == n1)
205		return -1;
206	if (i == n2)
207		return 1;
208	errx(1, "cmpndewey: cant happen");
209	return 0;
210}
211
212/*
213 * Search directories for a shared library matching the given
214 * major and minor version numbers.
215 *
216 * MAJOR == -1 && MINOR == -1	--> find highest version
217 * MAJOR != -1 && MINOR == -1   --> find highest minor version
218 * MAJOR == -1 && MINOR != -1   --> invalid
219 * MAJOR != -1 && MINOR != -1   --> find highest micro version
220 */
221
222/* Not interested in devices right now... */
223#undef major
224#undef minor
225
226static char *
227findshlib(char *name, int *majorp, int *minorp, int do_dot_a)
228{
229	int major = *majorp, minor = *minorp, ndewey, i, len;
230	int dewey[MAXDEWEY], tmp[MAXDEWEY];
231	char *lname;
232
233	len = strlen(name) + sizeof("lib");
234	lname = (char *)alloca(len);
235	snprintf(lname, len, "lib%s", name);
236
237	ndewey = 0;
238
239	for (i = 0; i < n_search_dirs; i++) {
240		struct dirent *dp;
241		char *path = NULL;
242		DIR *dd;
243
244		dd = opendir(search_dirs[i]);
245		if (dd == NULL)
246			continue;
247
248		while ((dp = readdir(dd)) != NULL) {
249			int	n;
250
251			if (do_dot_a && path == NULL &&
252			    dp->d_namlen == len + 2 &&
253			    strncmp(dp->d_name, lname, len) == 0 &&
254			    (dp->d_name+len)[0] == '.' &&
255			    (dp->d_name+len)[1] == 'a')
256				path = concat(search_dirs[i], "/", dp->d_name);
257
258			if (dp->d_namlen < len + 4)
259				continue;
260			if (strncmp(dp->d_name, lname, len) != 0)
261				continue;
262			if (strncmp(dp->d_name+len, ".so.", 4) != 0)
263				continue;
264
265			if ((n = getdewey(tmp, dp->d_name+len+4)) == 0)
266				continue;
267
268			/* skip inappropriate versions. */
269			if (major != -1) {
270				if (tmp[0] != major)
271					continue;
272				if (n != 1 && minor != -1 && tmp[1] < minor)
273					continue;
274			}
275
276			if (cmpndewey(tmp, n, dewey, ndewey) <= 0)
277				continue;
278
279			/* We have a better version */
280			if (path)
281				free(path);
282			path = concat(search_dirs[i], "/", dp->d_name);
283			bcopy(tmp, dewey, sizeof(dewey));
284			ndewey = n;
285			*majorp = dewey[0];
286			*minorp = dewey[1];
287		}
288		closedir(dd);
289
290		/* There's a lib in this dir; take it. */
291		if (path != NULL)
292			return path;
293	}
294	return NULL;
295}
296