FreeBSD-5.3/libexec/rtld-aout/shlib.c
/*
* Copyright (c) 1993 Paul Kranenburg
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Paul Kranenburg.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD: src/libexec/rtld-aout/shlib.c,v 1.23 2002/09/17 01:48:53 peter Exp $
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#include <a.out.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/link_aout.h>
#include "shlib.h"
#include "support.h"
/*
* Standard directories to search for files specified by -l.
*/
#ifndef STANDARD_SEARCH_DIRS
#define STANDARD_SEARCH_DIRS "/usr/lib/aout"
#endif
/*
* Actual vector of library search directories,
* including `-L'ed and LD_LIBRARY_PATH spec'd ones.
*/
char **search_dirs;
int n_search_dirs;
char *standard_search_dirs[] = {
STANDARD_SEARCH_DIRS
};
void
add_search_dir(name)
char *name;
{
int n;
for (n = 0; n < n_search_dirs; n++)
if (strcmp(search_dirs[n], name) == 0)
return;
n_search_dirs++;
search_dirs = (char **)
xrealloc(search_dirs, n_search_dirs * sizeof search_dirs[0]);
search_dirs[n_search_dirs - 1] = strdup(name);
}
void
add_search_path(path)
char *path;
{
register char *cp, *dup;
if (path == NULL)
return;
/* Add search directories from `path' */
path = dup = strdup(path);
while ((cp = strsep(&path, ":")) != NULL)
add_search_dir(cp);
free(dup);
}
void
std_search_path()
{
int i, n;
/* Append standard search directories */
n = sizeof standard_search_dirs / sizeof standard_search_dirs[0];
for (i = 0; i < n; i++)
add_search_dir(standard_search_dirs[i]);
}
/*
* Return true if CP points to a valid dewey number.
* Decode and leave the result in the array DEWEY.
* Return the number of decoded entries in DEWEY.
*/
int
getdewey(dewey, cp)
int dewey[];
char *cp;
{
int i, n;
for (n = 0, i = 0; i < MAXDEWEY; i++) {
if (*cp == '\0')
break;
if (*cp == '.') cp++;
if (!isdigit(*cp))
return 0;
dewey[n++] = strtol(cp, &cp, 10);
}
return n;
}
/*
* Compare two dewey arrays.
* Return -1 if `d1' represents a smaller value than `d2'.
* Return 1 if `d1' represents a greater value than `d2'.
* Return 0 if equal.
*/
int
cmpndewey(d1, n1, d2, n2)
int d1[], d2[];
int n1, n2;
{
register int i;
for (i = 0; i < n1 && i < n2; i++) {
if (d1[i] < d2[i])
return -1;
if (d1[i] > d2[i])
return 1;
}
if (n1 == n2)
return 0;
if (i == n1)
return -1;
if (i == n2)
return 1;
errx(1, "cmpndewey: cant happen");
return 0;
}
/*
* Search directories for a shared library matching the given
* major and minor version numbers. See search_lib_dir() below for
* the detailed matching rules.
*
* As soon as a directory with an acceptable match is found, the search
* terminates. Subsequent directories are not searched for a better
* match. This is in conformance with the SunOS searching rules. Also,
* it avoids a lot of directory searches that are virtually guaranteed to
* be fruitless.
*
* The return value is a full pathname to the matching library. The
* string is dynamically allocated. If no matching library is found, the
* function returns NULL.
*/
char *
findshlib(name, majorp, minorp, do_dot_a)
char *name;
int *majorp, *minorp;
int do_dot_a;
{
int i;
for (i = 0; i < n_search_dirs; i++) {
char *path;
path = search_lib_dir(search_dirs[i], name, majorp, minorp,
do_dot_a);
if(path != NULL)
return path;
}
return NULL;
}
/*
* Search library directories for a file with the given name. The
* return value is a full pathname to the matching file. The string
* is dynamically allocated. If no matching file is found, the function
* returns NULL.
*/
char *
find_lib_file(name)
const char *name;
{
int i;
for (i = 0; i < n_search_dirs; i++) {
char *path = concat(search_dirs[i], "/", name);
struct stat sb;
if (lstat(path, &sb) != -1) /* We found it */
return path;
free(path);
}
return NULL;
}
/*
* Search a given directory for a library (preferably shared) satisfying
* the given criteria.
*
* The matching rules are as follows:
*
* if(*majorp == -1)
* find the library with the highest major version;
* else
* insist on a major version identical to *majorp;
*
* Always find the library with the highest minor version;
* if(*minorp != -1)
* insist on a minor version >= *minorp;
*
* It is invalid to specify a specific minor number while wildcarding
* the major number.
*
* The actual major and minor numbers found are returned via the pointer
* arguments.
*
* A suitable shared library is always preferred over a static (.a) library.
* If do_dot_a is false, then a static library will not be accepted in
* any case.
*
* The return value is a full pathname to the matching library. The
* string is dynamically allocated. If no matching library is found, the
* function returns NULL.
*/
char *
search_lib_dir(dir, name, majorp, minorp, do_dot_a)
char *dir;
char *name;
int *majorp;
int *minorp;
int do_dot_a;
{
int namelen;
DIR *dd;
struct dirent *dp;
int best_dewey[MAXDEWEY];
int best_ndewey;
char dot_a_name[MAXNAMLEN+1];
char dot_so_name[MAXNAMLEN+1];
if((dd = opendir(dir)) == NULL)
return NULL;
namelen = strlen(name);
best_ndewey = 0;
dot_a_name[0] = '\0';
dot_so_name[0] = '\0';
while((dp = readdir(dd)) != NULL) {
char *extension;
if(strlen(dp->d_name) < 3 + namelen + 2 || /* lib+xxx+.a */
strncmp(dp->d_name, "lib", 3) != 0 ||
strncmp(dp->d_name + 3, name, namelen) != 0 ||
dp->d_name[3+namelen] != '.')
continue;
extension = dp->d_name + 3 + namelen + 1; /* a or so.* */
if(strncmp(extension, "so.", 3) == 0) {
int cur_dewey[MAXDEWEY];
int cur_ndewey;
cur_ndewey = getdewey(cur_dewey, extension+3);
if(cur_ndewey < 2) /* Too few version numbers */
continue;
if(*majorp != -1) { /* Need exact match on major */
if(cur_dewey[0] != *majorp)
continue;
if(*minorp != -1) { /* Need minor >= minimum */
if(cur_dewey[1] < *minorp)
continue;
}
}
if(cmpndewey(cur_dewey, cur_ndewey, best_dewey,
best_ndewey) <= 0) /* No better than prior match */
continue;
/* We found a better match */
strcpy(dot_so_name, dp->d_name);
bcopy(cur_dewey, best_dewey,
cur_ndewey * sizeof best_dewey[0]);
best_ndewey = cur_ndewey;
} else if(do_dot_a && strcmp(extension, "a") == 0)
strcpy(dot_a_name, dp->d_name);
}
closedir(dd);
if(dot_so_name[0] != '\0') {
*majorp = best_dewey[0];
*minorp = best_dewey[1];
return concat(dir, "/", dot_so_name);
}
if(dot_a_name[0] != '\0')
return concat(dir, "/", dot_a_name);
return NULL;
}