2
* Copyright (c) 2003-2007 Tim Kientzle
5
* Redistribution and use in source and binary forms, with or without
6
* modification, are permitted provided that the following conditions
8
* 1. Redistributions of source code must retain the above copyright
9
* notice, this list of conditions and the following disclaimer.
10
* 2. Redistributions in binary form must reproduce the above copyright
11
* notice, this list of conditions and the following disclaimer in the
12
* documentation and/or other materials provided with the distribution.
14
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
#include "archive_platform.h"
27
__FBSDID("$FreeBSD: head/lib/libarchive/archive_read_disk_set_standard_lookup.c 201109 2009-12-28 03:30:31Z kientzle $");
29
#ifdef HAVE_SYS_TYPES_H
30
#include <sys/types.h>
50
#if defined(_WIN32) && !defined(__CYGWIN__)
52
archive_read_disk_set_standard_lookup(struct archive *a)
54
archive_set_error(a, -1, "Standard lookups not available on Windows");
55
return (ARCHIVE_FATAL);
57
#else /* ! (_WIN32 && !__CYGWIN__) */
58
#define name_cache_size 127
60
static const char * const NO_NAME = "(noname)";
63
struct archive *archive;
72
} cache[name_cache_size];
75
static const char * lookup_gname(void *, gid_t);
76
static const char * lookup_uname(void *, uid_t);
77
static void cleanup(void *);
78
static const char * lookup_gname_helper(struct name_cache *, id_t gid);
79
static const char * lookup_uname_helper(struct name_cache *, id_t uid);
82
* Installs functions that use getpwuid()/getgrgid()---along with
83
* a simple cache to accelerate such lookups---into the archive_read_disk
84
* object. This is in a separate file because getpwuid()/getgrgid()
85
* can pull in a LOT of library code (including NIS/LDAP functions, which
86
* pull in DNS resolveers, etc). This can easily top 500kB, which makes
87
* it inappropriate for some space-constrained applications.
89
* Applications that are size-sensitive may want to just use the
90
* real default functions (defined in archive_read_disk.c) that just
91
* use the uid/gid without the lookup. Or define your own custom functions
95
archive_read_disk_set_standard_lookup(struct archive *a)
97
struct name_cache *ucache = malloc(sizeof(struct name_cache));
98
struct name_cache *gcache = malloc(sizeof(struct name_cache));
100
if (ucache == NULL || gcache == NULL) {
101
archive_set_error(a, ENOMEM,
102
"Can't allocate uname/gname lookup cache");
105
return (ARCHIVE_FATAL);
108
memset(ucache, 0, sizeof(*ucache));
110
ucache->size = name_cache_size;
111
memset(gcache, 0, sizeof(*gcache));
113
gcache->size = name_cache_size;
115
archive_read_disk_set_gname_lookup(a, gcache, lookup_gname, cleanup);
116
archive_read_disk_set_uname_lookup(a, ucache, lookup_uname, cleanup);
124
struct name_cache *cache = (struct name_cache *)data;
128
for (i = 0; i < cache->size; i++) {
129
if (cache->cache[i].name != NULL &&
130
cache->cache[i].name != NO_NAME)
131
free((void *)(uintptr_t)cache->cache[i].name);
139
* Lookup uid/gid from uname/gname, return NULL if no match.
142
lookup_name(struct name_cache *cache,
143
const char * (*lookup_fn)(struct name_cache *, id_t), id_t id)
151
slot = id % cache->size;
152
if (cache->cache[slot].name != NULL) {
153
if (cache->cache[slot].id == id) {
155
if (cache->cache[slot].name == NO_NAME)
157
return (cache->cache[slot].name);
159
if (cache->cache[slot].name != NO_NAME)
160
free((void *)(uintptr_t)cache->cache[slot].name);
161
cache->cache[slot].name = NULL;
164
name = (lookup_fn)(cache, id);
166
/* Cache and return the negative response. */
167
cache->cache[slot].name = NO_NAME;
168
cache->cache[slot].id = id;
172
cache->cache[slot].name = name;
173
cache->cache[slot].id = id;
174
return (cache->cache[slot].name);
178
lookup_uname(void *data, uid_t uid)
180
struct name_cache *uname_cache = (struct name_cache *)data;
181
return (lookup_name(uname_cache,
182
&lookup_uname_helper, (id_t)uid));
187
lookup_uname_helper(struct name_cache *cache, id_t id)
189
struct passwd pwent, *result;
192
if (cache->buff_size == 0) {
193
cache->buff_size = 256;
194
cache->buff = malloc(cache->buff_size);
196
if (cache->buff == NULL)
199
result = &pwent; /* Old getpwuid_r ignores last arg. */
200
r = getpwuid_r((uid_t)id, &pwent,
201
cache->buff, cache->buff_size, &result);
206
/* ERANGE means our buffer was too small, but POSIX
207
* doesn't tell us how big the buffer should be, so
208
* we just double it and try again. Because the buffer
209
* is kept around in the cache object, we shouldn't
210
* have to do this very often. */
211
cache->buff_size *= 2;
212
cache->buff = realloc(cache->buff, cache->buff_size);
213
if (cache->buff == NULL)
217
archive_set_error(cache->archive, errno,
218
"Can't lookup user for id %d", (int)id);
224
return strdup(result->pw_name);
228
lookup_uname_helper(struct name_cache *cache, id_t id)
230
struct passwd *result;
232
result = getpwuid((uid_t)id);
237
return strdup(result->pw_name);
242
lookup_gname(void *data, gid_t gid)
244
struct name_cache *gname_cache = (struct name_cache *)data;
245
return (lookup_name(gname_cache,
246
&lookup_gname_helper, (id_t)gid));
251
lookup_gname_helper(struct name_cache *cache, id_t id)
253
struct group grent, *result;
256
if (cache->buff_size == 0) {
257
cache->buff_size = 256;
258
cache->buff = malloc(cache->buff_size);
260
if (cache->buff == NULL)
263
result = &grent; /* Old getgrgid_r ignores last arg. */
264
r = getgrgid_r((gid_t)id, &grent,
265
cache->buff, cache->buff_size, &result);
270
/* ERANGE means our buffer was too small, but POSIX
271
* doesn't tell us how big the buffer should be, so
272
* we just double it and try again. */
273
cache->buff_size *= 2;
274
cache->buff = realloc(cache->buff, cache->buff_size);
275
if (cache->buff == NULL)
279
archive_set_error(cache->archive, errno,
280
"Can't lookup group for id %d", (int)id);
286
return strdup(result->gr_name);
290
lookup_gname_helper(struct name_cache *cache, id_t id)
292
struct group *result;
294
result = getgrgid((gid_t)id);
299
return strdup(result->gr_name);
303
#endif /* ! (_WIN32 && !__CYGWIN__) */