1 /* $NetBSD: citrus_iconv.c,v 1.10 2011/11/19 18:34:21 tnozaki Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c)2003 Citrus Project,
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/types.h>
32 #include <sys/queue.h>
33
34 #include <assert.h>
35 #include <dirent.h>
36 #include <errno.h>
37 #include <iconv.h>
38 #include <langinfo.h>
39 #include <limits.h>
40 #include <paths.h>
41 #include <stdbool.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46
47 #include "citrus_namespace.h"
48 #include "citrus_bcs.h"
49 #include "citrus_esdb.h"
50 #include "citrus_region.h"
51 #include "citrus_memstream.h"
52 #include "citrus_mmap.h"
53 #include "citrus_module.h"
54 #include "citrus_lock.h"
55 #include "citrus_lookup.h"
56 #include "citrus_hash.h"
57 #include "citrus_iconv.h"
58
59 #define _CITRUS_ICONV_DIR "iconv.dir"
60 #define _CITRUS_ICONV_ALIAS "iconv.alias"
61
62 #define CI_HASH_SIZE 101
63 #define CI_INITIAL_MAX_REUSE 5
64 #define CI_ENV_MAX_REUSE "ICONV_MAX_REUSE"
65
66 static bool isinit = false;
67 static int shared_max_reuse, shared_num_unused;
68 static _CITRUS_HASH_HEAD(, _citrus_iconv_shared, CI_HASH_SIZE) shared_pool;
69 static TAILQ_HEAD(, _citrus_iconv_shared) shared_unused;
70
71 static pthread_rwlock_t ci_lock = PTHREAD_RWLOCK_INITIALIZER;
72
73 static __inline void
init_cache(void)74 init_cache(void)
75 {
76
77 WLOCK(&ci_lock);
78 if (!isinit) {
79 _CITRUS_HASH_INIT(&shared_pool, CI_HASH_SIZE);
80 TAILQ_INIT(&shared_unused);
81 shared_max_reuse = -1;
82 if (secure_getenv(CI_ENV_MAX_REUSE) != NULL)
83 shared_max_reuse =
84 atoi(secure_getenv(CI_ENV_MAX_REUSE));
85 if (shared_max_reuse < 0)
86 shared_max_reuse = CI_INITIAL_MAX_REUSE;
87 isinit = true;
88 }
89 UNLOCK(&ci_lock);
90 }
91
92 static __inline void
close_shared(struct _citrus_iconv_shared * ci)93 close_shared(struct _citrus_iconv_shared *ci)
94 {
95
96 if (ci) {
97 if (ci->ci_module) {
98 if (ci->ci_ops) {
99 if (ci->ci_closure)
100 (*ci->ci_ops->io_uninit_shared)(ci);
101 free(ci->ci_ops);
102 }
103 _citrus_unload_module(ci->ci_module);
104 }
105 free(ci);
106 }
107 }
108
109 static __inline int
open_shared(struct _citrus_iconv_shared * __restrict * __restrict rci,const char * __restrict convname,const char * __restrict src,const char * __restrict dst)110 open_shared(struct _citrus_iconv_shared * __restrict * __restrict rci,
111 const char * __restrict convname, const char * __restrict src,
112 const char * __restrict dst)
113 {
114 struct _citrus_iconv_shared *ci;
115 _citrus_iconv_getops_t getops;
116 const char *module;
117 size_t len_convname;
118 int ret;
119
120 #ifdef INCOMPATIBLE_WITH_GNU_ICONV
121 /*
122 * Sadly, the gnu tools expect iconv to actually parse the
123 * byte stream and don't allow for a pass-through when
124 * the (src,dest) encodings are the same.
125 * See gettext-0.18.3+ NEWS:
126 * msgfmt now checks PO file headers more strictly with less
127 * false-positives.
128 * NetBSD, also, doesn't do the below pass-through.
129 *
130 * Also note that this currently falls short if dst options have been
131 * specified. It may be the case that we want to ignore EILSEQ, in which
132 * case we should also select iconv_std anyways. This trick, while
133 * clever, may not be worth it.
134 */
135 module = (strcmp(src, dst) != 0) ? "iconv_std" : "iconv_none";
136 #else
137 module = "iconv_std";
138 #endif
139
140 /* initialize iconv handle */
141 len_convname = strlen(convname);
142 ci = calloc(1, sizeof(*ci) + len_convname + 1);
143 if (!ci) {
144 ret = errno;
145 goto err;
146 }
147 ci->ci_convname = (void *)&ci[1];
148 memcpy(ci->ci_convname, convname, len_convname + 1);
149
150 /* load module */
151 ret = _citrus_load_module(&ci->ci_module, module);
152 if (ret)
153 goto err;
154
155 /* get operators */
156 getops = (_citrus_iconv_getops_t)_citrus_find_getops(ci->ci_module,
157 module, "iconv");
158 if (!getops) {
159 ret = EOPNOTSUPP;
160 goto err;
161 }
162 ci->ci_ops = malloc(sizeof(*ci->ci_ops));
163 if (!ci->ci_ops) {
164 ret = errno;
165 goto err;
166 }
167 ret = (*getops)(ci->ci_ops);
168 if (ret)
169 goto err;
170
171 if (ci->ci_ops->io_init_shared == NULL ||
172 ci->ci_ops->io_uninit_shared == NULL ||
173 ci->ci_ops->io_init_context == NULL ||
174 ci->ci_ops->io_uninit_context == NULL ||
175 ci->ci_ops->io_convert == NULL) {
176 ret = EINVAL;
177 goto err;
178 }
179
180 /* initialize the converter */
181 ret = (*ci->ci_ops->io_init_shared)(ci, src, dst);
182 if (ret)
183 goto err;
184
185 *rci = ci;
186
187 return (0);
188 err:
189 close_shared(ci);
190 return (ret);
191 }
192
193 static __inline int
hash_func(const char * key)194 hash_func(const char *key)
195 {
196
197 return (_string_hash_func(key, CI_HASH_SIZE));
198 }
199
200 static __inline int
match_func(struct _citrus_iconv_shared * __restrict ci,const char * __restrict key)201 match_func(struct _citrus_iconv_shared * __restrict ci,
202 const char * __restrict key)
203 {
204
205 return (strcmp(ci->ci_convname, key));
206 }
207
208 static int
get_shared(struct _citrus_iconv_shared * __restrict * __restrict rci,const char * src,const char * dst)209 get_shared(struct _citrus_iconv_shared * __restrict * __restrict rci,
210 const char *src, const char *dst)
211 {
212 struct _citrus_iconv_shared * ci;
213 char convname[PATH_MAX];
214 int hashval, ret = 0;
215
216 snprintf(convname, sizeof(convname), "%s/%s", src, dst);
217
218 WLOCK(&ci_lock);
219
220 /* lookup alread existing entry */
221 hashval = hash_func(convname);
222 _CITRUS_HASH_SEARCH(&shared_pool, ci, ci_hash_entry, match_func,
223 convname, hashval);
224 if (ci != NULL) {
225 /* found */
226 if (ci->ci_used_count == 0) {
227 TAILQ_REMOVE(&shared_unused, ci, ci_tailq_entry);
228 shared_num_unused--;
229 }
230 ci->ci_used_count++;
231 *rci = ci;
232 goto quit;
233 }
234
235 /* create new entry */
236 ret = open_shared(&ci, convname, src, dst);
237 if (ret)
238 goto quit;
239
240 _CITRUS_HASH_INSERT(&shared_pool, ci, ci_hash_entry, hashval);
241 ci->ci_used_count = 1;
242 *rci = ci;
243
244 quit:
245 UNLOCK(&ci_lock);
246
247 return (ret);
248 }
249
250 static void
release_shared(struct _citrus_iconv_shared * __restrict ci)251 release_shared(struct _citrus_iconv_shared * __restrict ci)
252 {
253
254 WLOCK(&ci_lock);
255 ci->ci_used_count--;
256 if (ci->ci_used_count == 0) {
257 /* put it into unused list */
258 shared_num_unused++;
259 TAILQ_INSERT_TAIL(&shared_unused, ci, ci_tailq_entry);
260 /* flood out */
261 while (shared_num_unused > shared_max_reuse) {
262 ci = TAILQ_FIRST(&shared_unused);
263 TAILQ_REMOVE(&shared_unused, ci, ci_tailq_entry);
264 _CITRUS_HASH_REMOVE(ci, ci_hash_entry);
265 shared_num_unused--;
266 close_shared(ci);
267 }
268 }
269
270 UNLOCK(&ci_lock);
271 }
272
273 /*
274 * _citrus_iconv_open:
275 * open a converter for the specified in/out codes.
276 */
277 int
_citrus_iconv_open(struct _citrus_iconv * __restrict * __restrict rcv,const char * __restrict src,const char * __restrict dst)278 _citrus_iconv_open(struct _citrus_iconv * __restrict * __restrict rcv,
279 const char * __restrict src, const char * __restrict dst)
280 {
281 struct _citrus_iconv *cv = NULL;
282 struct _citrus_iconv_shared *ci = NULL;
283 char realdst[PATH_MAX], realsrc[PATH_MAX], *slashes;
284 #ifdef _PATH_ICONV
285 char buf[PATH_MAX], path[PATH_MAX];
286 #endif
287 int ret;
288
289 init_cache();
290
291 /* GNU behaviour, using locale encoding if "" or "char" is specified */
292 if ((strcmp(src, "") == 0) || (strcmp(src, "char") == 0))
293 src = nl_langinfo(CODESET);
294 if ((strcmp(dst, "") == 0) || (strcmp(dst, "char") == 0))
295 dst = nl_langinfo(CODESET);
296
297 strlcpy(realsrc, src, (size_t)PATH_MAX);
298 if ((slashes = strstr(realsrc, "//")) != NULL)
299 *slashes = '\0';
300 strlcpy(realdst, dst, (size_t)PATH_MAX);
301 if ((slashes = strstr(realdst, "//")) != NULL)
302 *slashes = '\0';
303
304 /* resolve codeset name aliases */
305 #ifdef _PATH_ICONV
306 /*
307 * Note that the below reads from realsrc and realdst while it's
308 * repopulating (writing to) realsrc and realdst, but it's done so with
309 * a trip through `buf`.
310 */
311 snprintf(path, sizeof(path), "%s/%s", _PATH_ICONV, _CITRUS_ICONV_ALIAS);
312 strlcpy(realsrc, _lookup_alias(path, realsrc, buf, (size_t)PATH_MAX,
313 _LOOKUP_CASE_IGNORE), (size_t)PATH_MAX);
314 strlcpy(realdst, _lookup_alias(path, realdst, buf, (size_t)PATH_MAX,
315 _LOOKUP_CASE_IGNORE), (size_t)PATH_MAX);
316 #endif
317
318 /* sanity check */
319 if (strchr(realsrc, '/') != NULL || strchr(realdst, '/'))
320 return (EINVAL);
321
322 /* get shared record */
323 ret = get_shared(&ci, realsrc, realdst);
324 if (ret)
325 return (ret);
326
327 /* create/init context */
328 if (*rcv == NULL) {
329 cv = malloc(sizeof(*cv));
330 if (cv == NULL) {
331 ret = errno;
332 release_shared(ci);
333 return (ret);
334 }
335 *rcv = cv;
336 }
337 (*rcv)->cv_shared = ci;
338 ret = (*ci->ci_ops->io_init_context)(*rcv);
339 if (ret) {
340 release_shared(ci);
341 free(cv);
342 return (ret);
343 }
344 return (0);
345 }
346
347 /*
348 * _citrus_iconv_close:
349 * close the specified converter.
350 */
351 void
_citrus_iconv_close(struct _citrus_iconv * cv)352 _citrus_iconv_close(struct _citrus_iconv *cv)
353 {
354
355 if (cv) {
356 (*cv->cv_shared->ci_ops->io_uninit_context)(cv);
357 release_shared(cv->cv_shared);
358 free(cv);
359 }
360 }
361
362 const char
_citrus_iconv_canonicalize(const char * name)363 *_citrus_iconv_canonicalize(const char *name)
364 {
365 char *buf;
366
367 if ((buf = calloc((size_t)PATH_MAX, sizeof(*buf))) == NULL)
368 return (NULL);
369 _citrus_esdb_alias(name, buf, (size_t)PATH_MAX);
370 return (buf);
371 }
372