xref: /freebsd/lib/libc/iconv/citrus_csmapper.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /* $FreeBSD$ */
2 /*	$NetBSD: citrus_csmapper.c,v 1.11 2011/11/20 07:43:52 tnozaki Exp $	*/
3 
4 /*-
5  * Copyright (c)2003 Citrus Project,
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  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #include <sys/endian.h>
32 #include <sys/types.h>
33 #include <sys/queue.h>
34 
35 #include <assert.h>
36 #include <errno.h>
37 #include <limits.h>
38 #include <paths.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 #include "citrus_namespace.h"
44 #include "citrus_types.h"
45 #include "citrus_bcs.h"
46 #include "citrus_region.h"
47 #include "citrus_lock.h"
48 #include "citrus_memstream.h"
49 #include "citrus_mmap.h"
50 #include "citrus_module.h"
51 #include "citrus_hash.h"
52 #include "citrus_mapper.h"
53 #include "citrus_csmapper.h"
54 #include "citrus_pivot_file.h"
55 #include "citrus_db.h"
56 #include "citrus_db_hash.h"
57 #include "citrus_lookup.h"
58 
59 static struct _citrus_mapper_area	*maparea = NULL;
60 
61 static pthread_rwlock_t			ma_lock = PTHREAD_RWLOCK_INITIALIZER;
62 
63 #define CS_ALIAS	_PATH_CSMAPPER "/charset.alias"
64 #define CS_PIVOT	_PATH_CSMAPPER "/charset.pivot"
65 
66 
67 /* ---------------------------------------------------------------------- */
68 
69 static int
70 get32(struct _region *r, uint32_t *rval)
71 {
72 
73 	if (_region_size(r) != 4)
74 		return (EFTYPE);
75 
76 	memcpy(rval, _region_head(r), (size_t)4);
77 	*rval = be32toh(*rval);
78 
79 	return (0);
80 }
81 
82 static int
83 open_subdb(struct _citrus_db **subdb, struct _citrus_db *db, const char *src)
84 {
85 	struct _region r;
86 	int ret;
87 
88 	ret = _db_lookup_by_s(db, src, &r, NULL);
89 	if (ret)
90 		return (ret);
91 	ret = _db_open(subdb, &r, _CITRUS_PIVOT_SUB_MAGIC, _db_hash_std, NULL);
92 	if (ret)
93 		return (ret);
94 
95 	return (0);
96 }
97 
98 
99 #define NO_SUCH_FILE	EOPNOTSUPP
100 static int
101 find_best_pivot_pvdb(const char *src, const char *dst, char *pivot,
102     size_t pvlen, unsigned long *rnorm)
103 {
104 	struct _citrus_db *db1, *db2, *db3;
105 	struct _region fr, r1, r2;
106 	char buf[LINE_MAX];
107 	uint32_t val32;
108 	unsigned long norm;
109 	int i, num, ret;
110 
111 	ret = _map_file(&fr, CS_PIVOT ".pvdb");
112 	if (ret) {
113 		if (ret == ENOENT)
114 			ret = NO_SUCH_FILE;
115 		return (ret);
116 	}
117 	ret = _db_open(&db1, &fr, _CITRUS_PIVOT_MAGIC, _db_hash_std, NULL);
118 	if (ret)
119 		goto quit1;
120 	ret = open_subdb(&db2, db1, src);
121 	if (ret)
122 		goto quit2;
123 
124 	num = _db_get_num_entries(db2);
125 	*rnorm = ULONG_MAX;
126 	for (i = 0; i < num; i++) {
127 		/* iterate each pivot */
128 		ret = _db_get_entry(db2, i, &r1, &r2);
129 		if (ret)
130 			goto quit3;
131 		/* r1:pivot name, r2:norm among src and pivot */
132 		ret = get32(&r2, &val32);
133 		if (ret)
134 			goto quit3;
135 		norm = val32;
136 		snprintf(buf, sizeof(buf), "%.*s",
137 			 (int)_region_size(&r1), (char *)_region_head(&r1));
138 		/* buf: pivot name */
139 		ret = open_subdb(&db3, db1, buf);
140 		if (ret)
141 			goto quit3;
142 		if (_db_lookup_by_s(db3, dst, &r2, NULL) != 0)
143 			/* don't break the loop, test all src/dst pairs. */
144 			goto quit4;
145 		/* r2: norm among pivot and dst */
146 		ret = get32(&r2, &val32);
147 		if (ret)
148 			goto quit4;
149 		norm += val32;
150 		/* judge minimum norm */
151 		if (norm < *rnorm) {
152 			*rnorm = norm;
153 			strlcpy(pivot, buf, pvlen);
154 		}
155 quit4:
156 		_db_close(db3);
157 		if (ret)
158 			goto quit3;
159 	}
160 quit3:
161 	_db_close(db2);
162 quit2:
163 	_db_close(db1);
164 quit1:
165 	_unmap_file(&fr);
166 	if (ret)
167 		return (ret);
168 
169 	if (*rnorm == ULONG_MAX)
170 		return (ENOENT);
171 
172 	return (0);
173 }
174 
175 /* ---------------------------------------------------------------------- */
176 
177 struct zone {
178 	const char *begin, *end;
179 };
180 
181 struct parse_arg {
182 	char dst[PATH_MAX];
183 	unsigned long norm;
184 };
185 
186 static int
187 parse_line(struct parse_arg *pa, struct _region *r)
188 {
189 	struct zone z1, z2;
190 	char buf[20];
191 	size_t len;
192 
193 	len = _region_size(r);
194 	z1.begin = _bcs_skip_ws_len(_region_head(r), &len);
195 	if (len == 0)
196 		return (EFTYPE);
197 	z1.end = _bcs_skip_nonws_len(z1.begin, &len);
198 	if (len == 0)
199 		return (EFTYPE);
200 	z2.begin = _bcs_skip_ws_len(z1.end, &len);
201 	if (len == 0)
202 		return (EFTYPE);
203 	z2.end = _bcs_skip_nonws_len(z2.begin, &len);
204 
205 	/* z1 : dst name, z2 : norm */
206 	snprintf(pa->dst, sizeof(pa->dst),
207 	    "%.*s", (int)(z1.end-z1.begin), z1.begin);
208 	snprintf(buf, sizeof(buf),
209 	    "%.*s", (int)(z2.end-z2.begin), z2.begin);
210 	pa->norm = _bcs_strtoul(buf, NULL, 0);
211 
212 	return (0);
213 }
214 
215 static int
216 find_dst(struct parse_arg *pasrc, const char *dst)
217 {
218 	struct _lookup *cl;
219 	struct parse_arg padst;
220 	struct _region data;
221 	int ret;
222 
223 	ret = _lookup_seq_open(&cl, CS_PIVOT, _LOOKUP_CASE_IGNORE);
224 	if (ret)
225 		return (ret);
226 
227 	ret = _lookup_seq_lookup(cl, pasrc->dst, &data);
228 	while (ret == 0) {
229 		ret = parse_line(&padst, &data);
230 		if (ret)
231 			break;
232 		if (strcmp(dst, padst.dst) == 0) {
233 			pasrc->norm += padst.norm;
234 			break;
235 		}
236 		ret = _lookup_seq_next(cl, NULL, &data);
237 	}
238 	_lookup_seq_close(cl);
239 
240 	return (ret);
241 }
242 
243 static int
244 find_best_pivot_lookup(const char *src, const char *dst, char *pivot,
245     size_t pvlen, unsigned long *rnorm)
246 {
247 	struct _lookup *cl;
248 	struct _region data;
249 	struct parse_arg pa;
250 	char pivot_min[PATH_MAX];
251 	unsigned long norm_min;
252 	int ret;
253 
254 	ret = _lookup_seq_open(&cl, CS_PIVOT, _LOOKUP_CASE_IGNORE);
255 	if (ret)
256 		return (ret);
257 
258 	norm_min = ULONG_MAX;
259 
260 	/* find pivot code */
261 	ret = _lookup_seq_lookup(cl, src, &data);
262 	while (ret == 0) {
263 		ret = parse_line(&pa, &data);
264 		if (ret)
265 			break;
266 		ret = find_dst(&pa, dst);
267 		if (ret)
268 			break;
269 		if (pa.norm < norm_min) {
270 			norm_min = pa.norm;
271 			strlcpy(pivot_min, pa.dst, sizeof(pivot_min));
272 		}
273 		ret = _lookup_seq_next(cl, NULL, &data);
274 	}
275 	_lookup_seq_close(cl);
276 
277 	if (ret != ENOENT)
278 		return (ret);
279 	if (norm_min == ULONG_MAX)
280 		return (ENOENT);
281 	strlcpy(pivot, pivot_min, pvlen);
282 	if (rnorm)
283 		*rnorm = norm_min;
284 
285 	return (0);
286 }
287 
288 static int
289 find_best_pivot(const char *src, const char *dst, char *pivot, size_t pvlen,
290     unsigned long *rnorm)
291 {
292 	int ret;
293 
294 	ret = find_best_pivot_pvdb(src, dst, pivot, pvlen, rnorm);
295 	if (ret == NO_SUCH_FILE)
296 		ret = find_best_pivot_lookup(src, dst, pivot, pvlen, rnorm);
297 
298 	return (ret);
299 }
300 
301 static __inline int
302 open_serial_mapper(struct _citrus_mapper_area *__restrict ma,
303     struct _citrus_mapper * __restrict * __restrict rcm,
304     const char *src, const char *pivot, const char *dst)
305 {
306 	char buf[PATH_MAX];
307 
308 	snprintf(buf, sizeof(buf), "%s/%s,%s/%s", src, pivot, pivot, dst);
309 
310 	return (_mapper_open_direct(ma, rcm, "mapper_serial", buf));
311 }
312 
313 static struct _citrus_csmapper *csm_none = NULL;
314 static int
315 get_none(struct _citrus_mapper_area *__restrict ma,
316     struct _citrus_csmapper *__restrict *__restrict rcsm)
317 {
318 	int ret;
319 
320 	WLOCK(&ma_lock);
321 	if (csm_none) {
322 		*rcsm = csm_none;
323 		ret = 0;
324 		goto quit;
325 	}
326 
327 	ret = _mapper_open_direct(ma, &csm_none, "mapper_none", "");
328 	if (ret)
329 		goto quit;
330 	_mapper_set_persistent(csm_none);
331 
332 	*rcsm = csm_none;
333 	ret = 0;
334 quit:
335 	UNLOCK(&ma_lock);
336 	return (ret);
337 }
338 
339 int
340 _citrus_csmapper_open(struct _citrus_csmapper * __restrict * __restrict rcsm,
341     const char * __restrict src, const char * __restrict dst, uint32_t flags,
342     unsigned long *rnorm)
343 {
344 	const char *realsrc, *realdst;
345 	char buf1[PATH_MAX], buf2[PATH_MAX], key[PATH_MAX], pivot[PATH_MAX];
346 	unsigned long norm;
347 	int ret;
348 
349 	norm = 0;
350 
351 	ret = _citrus_mapper_create_area(&maparea, _PATH_CSMAPPER);
352 	if (ret)
353 		return (ret);
354 
355 	realsrc = _lookup_alias(CS_ALIAS, src, buf1, sizeof(buf1),
356 	    _LOOKUP_CASE_IGNORE);
357 	realdst = _lookup_alias(CS_ALIAS, dst, buf2, sizeof(buf2),
358 	    _LOOKUP_CASE_IGNORE);
359 	if (!strcmp(realsrc, realdst)) {
360 		ret = get_none(maparea, rcsm);
361 		if (ret == 0 && rnorm != NULL)
362 			*rnorm = 0;
363 		return (ret);
364 	}
365 
366 	snprintf(key, sizeof(key), "%s/%s", realsrc, realdst);
367 
368 	ret = _mapper_open(maparea, rcsm, key);
369 	if (ret == 0) {
370 		if (rnorm != NULL)
371 			*rnorm = 0;
372 		return (0);
373 	}
374 	if (ret != ENOENT || (flags & _CSMAPPER_F_PREVENT_PIVOT)!=0)
375 		return (ret);
376 
377 	ret = find_best_pivot(realsrc, realdst, pivot, sizeof(pivot), &norm);
378 	if (ret)
379 		return (ret);
380 
381 	ret = open_serial_mapper(maparea, rcsm, realsrc, pivot, realdst);
382 	if (ret == 0 && rnorm != NULL)
383 		*rnorm = norm;
384 
385 	return (ret);
386 }
387