1/* Copyright (C) 1996-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper, <drepper@gnu.org>.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
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 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <byteswap.h>
20#include <endian.h>
21#include <errno.h>
22#include <fcntl.h>
23#include <string.h>
24#include <stdlib.h>
25#include <unistd.h>
26#ifdef _POSIX_MAPPED_FILES
27# include <sys/mman.h>
28#endif
29#include <sys/stat.h>
30
31#include "catgetsinfo.h"
32#include <not-cancel.h>
33
34
35#define SWAPU32(w) bswap_32 (w)
36
37
38int
39__open_catalog (const char *cat_name, const char *nlspath, const char *env_var,
40 __nl_catd catalog)
41{
42 int fd = -1;
43 struct stat64 st;
44 int swapping;
45 size_t cnt;
46 size_t max_offset;
47 size_t tab_size;
48 const char *lastp;
49 int result = -1;
50 char *buf = NULL;
51
52 if (strchr (cat_name, '/') != NULL || nlspath == NULL)
53 fd = __open_nocancel (cat_name, O_RDONLY);
54 else
55 {
56 const char *run_nlspath = nlspath;
57#define ENOUGH(n) \
58 if (__glibc_unlikely (bufact + (n) >= bufmax)) \
59 { \
60 char *old_buf = buf; \
61 bufmax += (bufmax < 256 + (n)) ? 256 + (n) : bufmax; \
62 buf = realloc (buf, bufmax); \
63 if (__glibc_unlikely (buf == NULL)) \
64 { \
65 free (old_buf); \
66 return -1; \
67 } \
68 }
69
70 /* The RUN_NLSPATH variable contains a colon separated list of
71 descriptions where we expect to find catalogs. We have to
72 recognize certain % substitutions and stop when we found the
73 first existing file. */
74 size_t bufact;
75 size_t bufmax = 0;
76 size_t len;
77
78 fd = -1;
79 while (*run_nlspath != '\0')
80 {
81 bufact = 0;
82
83 if (*run_nlspath == ':')
84 {
85 /* Leading colon or adjacent colons - treat same as %N. */
86 len = strlen (cat_name);
87 ENOUGH (len);
88 memcpy (&buf[bufact], cat_name, len);
89 bufact += len;
90 }
91 else
92 while (*run_nlspath != ':' && *run_nlspath != '\0')
93 if (*run_nlspath == '%')
94 {
95 const char *tmp;
96
97 ++run_nlspath; /* We have seen the `%'. */
98 switch (*run_nlspath++)
99 {
100 case 'N':
101 /* Use the catalog name. */
102 len = strlen (cat_name);
103 ENOUGH (len);
104 memcpy (&buf[bufact], cat_name, len);
105 bufact += len;
106 break;
107 case 'L':
108 /* Use the current locale category value. */
109 len = strlen (env_var);
110 ENOUGH (len);
111 memcpy (&buf[bufact], env_var, len);
112 bufact += len;
113 break;
114 case 'l':
115 /* Use language element of locale category value. */
116 tmp = env_var;
117 do
118 {
119 ENOUGH (1);
120 buf[bufact++] = *tmp++;
121 }
122 while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
123 break;
124 case 't':
125 /* Use territory element of locale category value. */
126 tmp = env_var;
127 do
128 ++tmp;
129 while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
130 if (*tmp == '_')
131 {
132 ++tmp;
133 do
134 {
135 ENOUGH (1);
136 buf[bufact++] = *tmp++;
137 }
138 while (*tmp != '\0' && *tmp != '.');
139 }
140 break;
141 case 'c':
142 /* Use code set element of locale category value. */
143 tmp = env_var;
144 do
145 ++tmp;
146 while (*tmp != '\0' && *tmp != '.');
147 if (*tmp == '.')
148 {
149 ++tmp;
150 do
151 {
152 ENOUGH (1);
153 buf[bufact++] = *tmp++;
154 }
155 while (*tmp != '\0');
156 }
157 break;
158 case '%':
159 ENOUGH (1);
160 buf[bufact++] = '%';
161 break;
162 default:
163 /* Unknown variable: ignore this path element. */
164 bufact = 0;
165 while (*run_nlspath != '\0' && *run_nlspath != ':')
166 ++run_nlspath;
167 break;
168 }
169 }
170 else
171 {
172 ENOUGH (1);
173 buf[bufact++] = *run_nlspath++;
174 }
175
176 ENOUGH (1);
177 buf[bufact] = '\0';
178
179 if (bufact != 0)
180 {
181 fd = __open_nocancel (buf, O_RDONLY);
182 if (fd >= 0)
183 break;
184 }
185
186 ++run_nlspath;
187 }
188 }
189
190 /* Avoid dealing with directories and block devices */
191 if (__builtin_expect (fd, 0) < 0)
192 {
193 free (buf);
194 return -1;
195 }
196
197 if (__builtin_expect (__fstat64 (fd, &st), 0) < 0)
198 goto close_unlock_return;
199
200 if (__builtin_expect (!S_ISREG (st.st_mode), 0)
201 || (size_t) st.st_size < sizeof (struct catalog_obj))
202 {
203 /* `errno' is not set correctly but the file is not usable.
204 Use an reasonable error value. */
205 __set_errno (EINVAL);
206 goto close_unlock_return;
207 }
208
209 catalog->file_size = st.st_size;
210#ifdef _POSIX_MAPPED_FILES
211# ifndef MAP_COPY
212 /* Linux seems to lack read-only copy-on-write. */
213# define MAP_COPY MAP_PRIVATE
214# endif
215# ifndef MAP_FILE
216 /* Some systems do not have this flag; it is superfluous. */
217# define MAP_FILE 0
218# endif
219 catalog->file_ptr =
220 (struct catalog_obj *) __mmap (NULL, st.st_size, PROT_READ,
221 MAP_FILE|MAP_COPY, fd, 0);
222 if (__builtin_expect (catalog->file_ptr != (struct catalog_obj *) MAP_FAILED,
223 1))
224 /* Tell the world we managed to mmap the file. */
225 catalog->status = mmapped;
226 else
227#endif /* _POSIX_MAPPED_FILES */
228 {
229 /* mmap failed perhaps because the system call is not
230 implemented. Try to load the file. */
231 size_t todo;
232 catalog->file_ptr = malloc (st.st_size);
233 if (catalog->file_ptr == NULL)
234 goto close_unlock_return;
235
236 todo = st.st_size;
237 /* Save read, handle partial reads. */
238 do
239 {
240 size_t now = __read_nocancel (fd, (((char *) catalog->file_ptr)
241 + (st.st_size - todo)), todo);
242 if (now == 0 || now == (size_t) -1)
243 {
244#ifdef EINTR
245 if (now == (size_t) -1 && errno == EINTR)
246 continue;
247#endif
248 free ((void *) catalog->file_ptr);
249 goto close_unlock_return;
250 }
251 todo -= now;
252 }
253 while (todo > 0);
254 catalog->status = malloced;
255 }
256
257 /* Determine whether the file is a catalog file and if yes whether
258 it is written using the correct byte order. Else we have to swap
259 the values. */
260 if (__glibc_likely (catalog->file_ptr->magic == CATGETS_MAGIC))
261 swapping = 0;
262 else if (catalog->file_ptr->magic == SWAPU32 (CATGETS_MAGIC))
263 swapping = 1;
264 else
265 {
266 invalid_file:
267 /* Invalid file. Free the resources and mark catalog as not
268 usable. */
269#ifdef _POSIX_MAPPED_FILES
270 if (catalog->status == mmapped)
271 __munmap ((void *) catalog->file_ptr, catalog->file_size);
272 else
273#endif /* _POSIX_MAPPED_FILES */
274 free (catalog->file_ptr);
275 goto close_unlock_return;
276 }
277
278#define SWAP(x) (swapping ? SWAPU32 (x) : (x))
279
280 /* Get dimensions of the used hashing table. */
281 catalog->plane_size = SWAP (catalog->file_ptr->plane_size);
282 catalog->plane_depth = SWAP (catalog->file_ptr->plane_depth);
283
284 /* The file contains two versions of the pointer tables. Pick the
285 right one for the local byte order. */
286#if __BYTE_ORDER == __LITTLE_ENDIAN
287 catalog->name_ptr = &catalog->file_ptr->name_ptr[0];
288#elif __BYTE_ORDER == __BIG_ENDIAN
289 catalog->name_ptr = &catalog->file_ptr->name_ptr[catalog->plane_size
290 * catalog->plane_depth
291 * 3];
292#else
293# error Cannot handle __BYTE_ORDER byte order
294#endif
295
296 /* The rest of the file contains all the strings. They are
297 addressed relative to the position of the first string. */
298 catalog->strings =
299 (const char *) &catalog->file_ptr->name_ptr[catalog->plane_size
300 * catalog->plane_depth * 3 * 2];
301
302 /* Determine the largest string offset mentioned in the table. */
303 max_offset = 0;
304 tab_size = 3 * catalog->plane_size * catalog->plane_depth;
305 for (cnt = 2; cnt < tab_size; cnt += 3)
306 if (catalog->name_ptr[cnt] > max_offset)
307 max_offset = catalog->name_ptr[cnt];
308
309 /* Now we can check whether the file is large enough to contain the
310 tables it says it contains. */
311 if ((size_t) st.st_size
312 <= (sizeof (struct catalog_obj) + 2 * tab_size + max_offset))
313 /* The last string is not contained in the file. */
314 goto invalid_file;
315
316 lastp = catalog->strings + max_offset;
317 max_offset = (st.st_size
318 - sizeof (struct catalog_obj) + 2 * tab_size + max_offset);
319 while (*lastp != '\0')
320 {
321 if (--max_offset == 0)
322 goto invalid_file;
323 ++lastp;
324 }
325
326 /* We succeeded. */
327 result = 0;
328
329 /* Release the lock again. */
330 close_unlock_return:
331 __close_nocancel_nostatus (fd);
332 free (buf);
333
334 return result;
335}
336libc_hidden_def (__open_catalog)
337