1 /* Support for reading /etc/ld.so.cache files written by Linux ldconfig.
2 Copyright (C) 1996 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If
17 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
18 Cambridge, MA 02139, USA. */
24 /* System-dependent function to read a file's whole contents
25 in the most convenient manner available. */
26 extern void *_dl_sysdep_read_whole_file (const char *filename,
30 #define CACHEMAGIC "ld.so-1.7.0"
34 char magic[sizeof CACHEMAGIC - 1];
38 int flags; /* This is 1 for an ELF library. */
39 unsigned int key, value; /* String table indices. */
43 /* Look up NAME in ld.so.cache and return the file name stored there,
44 or null if none is found. */
47 _dl_load_cache_lookup (const char *name)
49 static struct cache_file *cache;
50 static size_t cachesize;
53 if (cache == (void *) -1)
54 /* Previously looked for the cache file and didn't find it. */
59 /* Read the contents of the file. */
60 void *file = _dl_sysdep_read_whole_file ("/etc/ld.so.cache", &cachesize,
62 if (file && cachesize > sizeof *cache &&
63 !memcmp (file, CACHEMAGIC, sizeof CACHEMAGIC - 1))
69 __munmap (file, cachesize);
75 for (i = 0; i < cache->nlibs; ++i)
76 if (cache->libs[i].flags == 1 && /* ELF library entry. */
77 /* Make sure string table indices are not bogus before using them. */
78 cache->libs[i].key < cachesize - sizeof *cache &&
79 cache->libs[i].value < cachesize - sizeof *cache &&
80 /* Does the name match? */
81 ! strcmp (name, ((const char *) &cache->libs[cache->nlibs] +
83 return (const char *) &cache->libs[cache->nlibs] + cache->libs[i].value;