1/* Copyright (C) 1996-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <byteswap.h>
19#include <endian.h>
20#include <errno.h>
21#include <fcntl.h>
22#include <string.h>
23#include <stdlib.h>
24#include <unistd.h>
25#ifdef _POSIX_MAPPED_FILES
26# include <sys/mman.h>
27#endif
28#include <sys/stat.h>
29
30#include "catgetsinfo.h"
31#include <not-cancel.h>
32
33
34#define SWAPU32(w) bswap_32 (w)
35
36
37int
38__open_catalog (const char *cat_name, const char *nlspath, const char *env_var,
39 __nl_catd catalog)
40{
41 int fd = -1;
42 struct __stat64_t64 st;
43 int swapping;
44 size_t cnt;
45 size_t max_offset;
46 size_t tab_size;
47 const char *lastp;
48 int result = -1;
49 char *buf = NULL;
50
51 if (strchr (cat_name, '/') != NULL || nlspath == NULL)
52 fd = __open_nocancel (cat_name, O_RDONLY | O_CLOEXEC);
53 else
54 {
55 const char *run_nlspath = nlspath;
56#define ENOUGH(n) \
57 if (__glibc_unlikely (bufact + (n) >= bufmax)) \
58 { \
59 char *old_buf = buf; \
60 bufmax += (bufmax < 256 + (n)) ? 256 + (n) : bufmax; \
61 buf = realloc (buf, bufmax); \
62 if (__glibc_unlikely (buf == NULL)) \
63 { \
64 free (old_buf); \
65 return -1; \
66 } \
67 }
68
69 /* The RUN_NLSPATH variable contains a colon separated list of
70 descriptions where we expect to find catalogs. We have to
71 recognize certain % substitutions and stop when we found the
72 first existing file. */
73 size_t bufact;
74 size_t bufmax = 0;
75 size_t len;
76
77 fd = -1;
78 while (*run_nlspath != '\0')
79 {
80 bufact = 0;
81
82 if (*run_nlspath == ':')
83 {
84 /* Leading colon or adjacent colons - treat same as %N. */
85 len = strlen (cat_name);
86 ENOUGH (len);
87 memcpy (&buf[bufact], cat_name, len);
88 bufact += len;
89 }
90 else
91 while (*run_nlspath != ':' && *run_nlspath != '\0')
92 if (*run_nlspath == '%')
93 {
94 const char *tmp;
95
96 ++run_nlspath; /* We have seen the `%'. */
97 switch (*run_nlspath++)
98 {
99 case 'N':
100 /* Use the catalog name. */
101 len = strlen (cat_name);
102 ENOUGH (len);
103 memcpy (&buf[bufact], cat_name, len);
104 bufact += len;
105 break;
106 case 'L':
107 /* Use the current locale category value. */
108 len = strlen (env_var);
109 ENOUGH (len);
110 memcpy (&buf[bufact], env_var, len);
111 bufact += len;
112 break;
113 case 'l':
114 /* Use language element of locale category value. */
115 tmp = env_var;
116 do
117 {
118 ENOUGH (1);
119 buf[bufact++] = *tmp++;
120 }
121 while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
122 break;
123 case 't':
124 /* Use territory element of locale category value. */
125 tmp = env_var;
126 do
127 ++tmp;
128 while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
129 if (*tmp == '_')
130 {
131 ++tmp;
132 do
133 {
134 ENOUGH (1);
135 buf[bufact++] = *tmp++;
136 }
137 while (*tmp != '\0' && *tmp != '.');
138 }
139 break;
140 case 'c':
141 /* Use code set element of locale category value. */
142 tmp = env_var;
143 do
144 ++tmp;
145 while (*tmp != '\0' && *tmp != '.');
146 if (*tmp == '.')
147 {
148 ++tmp;
149 do
150 {
151 ENOUGH (1);
152 buf[bufact++] = *tmp++;
153 }
154 while (*tmp != '\0');
155 }
156 break;
157 case '%':
158 ENOUGH (1);
159 buf[bufact++] = '%';
160 break;
161 default:
162 /* Unknown variable: ignore this path element. */
163 bufact = 0;
164 while (*run_nlspath != '\0' && *run_nlspath != ':')
165 ++run_nlspath;
166 break;
167 }
168 }
169 else
170 {
171 ENOUGH (1);
172 buf[bufact++] = *run_nlspath++;
173 }
174
175 ENOUGH (1);
176 buf[bufact] = '\0';
177
178 if (bufact != 0)
179 {
180 fd = __open_nocancel (buf, O_RDONLY | O_CLOEXEC);
181 if (fd >= 0)
182 break;
183 }
184
185 ++run_nlspath;
186 }
187 }
188
189 /* Avoid dealing with directories and block devices */
190 if (__builtin_expect (fd, 0) < 0)
191 {
192 free (buf);
193 return -1;
194 }
195
196 if (__glibc_unlikely (__fstat64_time64 (fd, &st) < 0))
197 goto close_unlock_return;
198
199 if (__builtin_expect (!S_ISREG (st.st_mode), 0)
200 || (size_t) st.st_size < sizeof (struct catalog_obj))
201 {
202 /* `errno' is not set correctly but the file is not usable.
203 Use an reasonable error value. */
204 __set_errno (EINVAL);
205 goto close_unlock_return;
206 }
207
208 catalog->file_size = st.st_size;
209#ifdef _POSIX_MAPPED_FILES
210# ifndef MAP_COPY
211 /* Linux seems to lack read-only copy-on-write. */
212# define MAP_COPY MAP_PRIVATE
213# endif
214# ifndef MAP_FILE
215 /* Some systems do not have this flag; it is superfluous. */
216# define MAP_FILE 0
217# endif
218 catalog->file_ptr =
219 (struct catalog_obj *) __mmap (NULL, st.st_size, PROT_READ,
220 MAP_FILE|MAP_COPY, fd, 0);
221 if (__builtin_expect (catalog->file_ptr != (struct catalog_obj *) MAP_FAILED,
222 1))
223 /* Tell the world we managed to mmap the file. */
224 catalog->status = mmapped;
225 else
226#endif /* _POSIX_MAPPED_FILES */
227 {
228 /* mmap failed perhaps because the system call is not
229 implemented. Try to load the file. */
230 size_t todo;
231 catalog->file_ptr = malloc (st.st_size);
232 if (catalog->file_ptr == NULL)
233 goto close_unlock_return;
234
235 todo = st.st_size;
236 /* Save read, handle partial reads. */
237 do
238 {
239 size_t now = __read_nocancel (fd, (((char *) catalog->file_ptr)
240 + (st.st_size - todo)), todo);
241 if (now == 0 || now == (size_t) -1)
242 {
243#ifdef EINTR
244 if (now == (size_t) -1 && errno == EINTR)
245 continue;
246#endif
247 free ((void *) catalog->file_ptr);
248 goto close_unlock_return;
249 }
250 todo -= now;
251 }
252 while (todo > 0);
253 catalog->status = malloced;
254 }
255
256 /* Determine whether the file is a catalog file and if yes whether
257 it is written using the correct byte order. Else we have to swap
258 the values. */
259 if (__glibc_likely (catalog->file_ptr->magic == CATGETS_MAGIC))
260 swapping = 0;
261 else if (catalog->file_ptr->magic == SWAPU32 (CATGETS_MAGIC))
262 swapping = 1;
263 else
264 {
265 invalid_file:
266 /* Invalid file. Free the resources and mark catalog as not
267 usable. */
268#ifdef _POSIX_MAPPED_FILES
269 if (catalog->status == mmapped)
270 __munmap ((void *) catalog->file_ptr, catalog->file_size);
271 else
272#endif /* _POSIX_MAPPED_FILES */
273 free (catalog->file_ptr);
274 goto close_unlock_return;
275 }
276
277#define SWAP(x) (swapping ? SWAPU32 (x) : (x))
278
279 /* Get dimensions of the used hashing table. */
280 catalog->plane_size = SWAP (catalog->file_ptr->plane_size);
281 catalog->plane_depth = SWAP (catalog->file_ptr->plane_depth);
282
283 /* The file contains two versions of the pointer tables. Pick the
284 right one for the local byte order. */
285#if __BYTE_ORDER == __LITTLE_ENDIAN
286 catalog->name_ptr = &catalog->file_ptr->name_ptr[0];
287#elif __BYTE_ORDER == __BIG_ENDIAN
288 catalog->name_ptr = &catalog->file_ptr->name_ptr[catalog->plane_size
289 * catalog->plane_depth
290 * 3];
291#else
292# error Cannot handle __BYTE_ORDER byte order
293#endif
294
295 /* The rest of the file contains all the strings. They are
296 addressed relative to the position of the first string. */
297 catalog->strings =
298 (const char *) &catalog->file_ptr->name_ptr[catalog->plane_size
299 * catalog->plane_depth * 3 * 2];
300
301 /* Determine the largest string offset mentioned in the table. */
302 max_offset = 0;
303 tab_size = 3 * catalog->plane_size * catalog->plane_depth;
304 for (cnt = 2; cnt < tab_size; cnt += 3)
305 if (catalog->name_ptr[cnt] > max_offset)
306 max_offset = catalog->name_ptr[cnt];
307
308 /* Now we can check whether the file is large enough to contain the
309 tables it says it contains. */
310 if ((size_t) st.st_size
311 <= (sizeof (struct catalog_obj) + 2 * tab_size + max_offset))
312 /* The last string is not contained in the file. */
313 goto invalid_file;
314
315 lastp = catalog->strings + max_offset;
316 max_offset = (st.st_size
317 - sizeof (struct catalog_obj) + 2 * tab_size + max_offset);
318 while (*lastp != '\0')
319 {
320 if (--max_offset == 0)
321 goto invalid_file;
322 ++lastp;
323 }
324
325 /* We succeeded. */
326 result = 0;
327
328 /* Release the lock again. */
329 close_unlock_return:
330 __close_nocancel_nostatus (fd);
331 free (buf);
332
333 return result;
334}
335libc_hidden_def (__open_catalog)
336