summary refs log tree commit diff
path: root/catgets/open_catalog.c
blob: e4b61d779af7fe45229d7840414050a4e84ddc19 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
/* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper, <drepper@gnu.ai.mit.edu>.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <byteswap.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#ifdef _POSIX_MAPPED_FILES
# include <sys/mman.h>
#endif
#include <sys/stat.h>

#include "catgetsinfo.h"


#define SWAPU32(w) bswap_32 (w)


void
__open_catalog (__nl_catd catalog)
{
  int fd = -1;
  struct stat st;
  int swapping;
  size_t cnt;
  size_t max_offset;
  size_t tab_size;
  const char *lastp;

  /* Make sure we are alone.  */
  __libc_lock_lock (catalog->lock);

  /* Check whether there was no other thread faster.  */
  if (catalog->status != closed)
    /* While we waited some other thread tried to open the catalog.  */
    goto unlock_return;

  if (strchr (catalog->cat_name, '/') != NULL || catalog->nlspath == NULL)
    fd = __open (catalog->cat_name, O_RDONLY);
  else
    {
      const char *run_nlspath = catalog->nlspath;
#define ENOUGH(n)							      \
  if (bufact + (n) >=bufmax) 						      \
    {									      \
      char *old_buf = buf;						      \
      bufmax += 256 + (n);						      \
      buf = (char *) alloca (bufmax);					      \
      memcpy (buf, old_buf, bufact);					      \
    }

      /* The RUN_NLSPATH variable contains a colon separated list of
	 descriptions where we expect to find catalogs.  We have to
	 recognize certain % substitutions and stop when we found the
	 first existing file.  */
      char *buf;
      size_t bufact;
      size_t bufmax;
      size_t len;

      buf = NULL;
      bufmax = 0;

      fd = -1;
      while (*run_nlspath != '\0')
	{
	  bufact = 0;
	  while (*run_nlspath != ':' && *run_nlspath != '\0')
	    if (*run_nlspath == '%')
	      {
		const char *tmp;

		++run_nlspath;	/* We have seen the `%'.  */
		switch (*run_nlspath++)
		  {
		  case 'N':
		    /* Use the catalog name.  */
		    len = strlen (catalog->cat_name);
		    ENOUGH (len);
		    memcpy (&buf[bufact], catalog->cat_name, len);
		    bufact += len;
		    break;
		  case 'L':
		    /* Use the current locale category value.  */
		    len = strlen (catalog->env_var);
		    ENOUGH (len);
		    memcpy (&buf[bufact], catalog->env_var, len);
		    bufact += len;
		    break;
		  case 'l':
		    /* Use language element of locale category value.  */
		    tmp = catalog->env_var;
		    do
		      {
			ENOUGH (1);
			buf[bufact++] = *tmp++;
		      }
		    while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
		    break;
		  case 't':
		    /* Use territory element of locale category value.  */
		    tmp = catalog->env_var;
		    do
		      ++tmp;
		    while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
		    if (*tmp == '_')
		      {
			++tmp;
			do
			  {
			    ENOUGH (1);
			    buf[bufact++] = *tmp;
			  }
			while (*tmp != '\0' && *tmp != '.');
		      }
		    break;
		  case 'c':
		    /* Use code set element of locale category value.  */
		    tmp = catalog->env_var;
		    do
		      ++tmp;
		    while (*tmp != '\0' && *tmp != '.');
		    if (*tmp == '.')
		      {
			++tmp;
			do
			  {
			    ENOUGH (1);
			    buf[bufact++] = *tmp;
			  }
			while (*tmp != '\0');
		      }
		    break;
		  case '%':
		    ENOUGH (1);
		    buf[bufact++] = '%';
		    break;
		  default:
		    /* Unknown variable: ignore this path element.  */
		    bufact = 0;
		    while (*run_nlspath != '\0' && *run_nlspath != ':')
		      ++run_nlspath;
		    break;
		  }
	      }
	    else
	      {
		ENOUGH (1);
		buf[bufact++] = *run_nlspath++;
	      }
	  ENOUGH (1);
	  buf[bufact] = '\0';

	  if (bufact != 0)
	    {
	      fd = __open (buf, O_RDONLY);
	      if (fd >= 0)
		break;
	    }

	  ++run_nlspath;
	}
    }

  /* Avoid dealing with directories and block devices */
  if (fd < 0 || __fstat (fd, &st) < 0)
    {
      catalog->status = nonexisting;
      goto unlock_return;
    }
  if (!S_ISREG (st.st_mode) || st.st_size < sizeof (struct catalog_obj))
    {
      /* `errno' is not set correctly but the file is not usable.
	 Use an reasonable error value.  */
      __set_errno (EINVAL);
      catalog->status = nonexisting;
      goto unlock_return;
    }

  catalog->file_size = st.st_size;
#ifdef _POSIX_MAPPED_FILES
# ifndef MAP_COPY
    /* Linux seems to lack read-only copy-on-write.  */
#  define MAP_COPY MAP_PRIVATE
# endif
# ifndef MAP_FILE
    /* Some systems do not have this flag; it is superfluous.  */
#  define MAP_FILE 0
# endif
# ifndef MAP_INHERIT
    /* Some systems might lack this; they lose.  */
#  define MAP_INHERIT 0
# endif
  catalog->file_ptr =
    (struct catalog_obj *) __mmap (NULL, st.st_size, PROT_READ,
				   MAP_FILE|MAP_COPY|MAP_INHERIT, fd, 0);
  if (catalog->file_ptr != (struct catalog_obj *) MAP_FAILED)
    /* Tell the world we managed to mmap the file.  */
    catalog->status = mmapped;
  else
#endif /* _POSIX_MAPPED_FILES */
    {
      /* mmap failed perhaps because the system call is not
	 implemented.  Try to load the file.  */
      size_t todo;
      catalog->file_ptr = malloc (st.st_size);
      if (catalog->file_ptr == NULL)
	{
	  catalog->status = nonexisting;
	  goto unlock_return;
	}
      todo = st.st_size;
      /* Save read, handle partial reads.  */
      do
	{
	  size_t now = __read (fd, (((char *) &catalog->file_ptr)
				    + (st.st_size - todo)), todo);
	  if (now == 0)
	    {
	      free ((void *) catalog->file_ptr);
	      catalog->status = nonexisting;
	      goto unlock_return;
	    }
	  todo -= now;
	}
      while (todo > 0);
      catalog->status = malloced;
    }

  /* We don't need the file anymore.  */
  __close (fd);
  fd = -1;

  /* Determine whether the file is a catalog file and if yes whether
     it is written using the correct byte order.  Else we have to swap
     the values.  */
  if (catalog->file_ptr->magic == CATGETS_MAGIC)
    swapping = 0;
  else if (catalog->file_ptr->magic == SWAPU32 (CATGETS_MAGIC))
    swapping = 1;
  else
    {
    invalid_file:
      /* Invalid file.  Free the resources and mark catalog as not
	 usable.  */
#ifdef _POSIX_MAPPED_FILES
      if (catalog->status == mmapped)
	__munmap ((void *) catalog->file_ptr, catalog->file_size);
      else
#endif	/* _POSIX_MAPPED_FILES */
	free (catalog->file_ptr);
      catalog->status = nonexisting;
      goto unlock_return;
    }

#define SWAP(x) (swapping ? SWAPU32 (x) : (x))

  /* Get dimensions of the used hashing table.  */
  catalog->plane_size = SWAP (catalog->file_ptr->plane_size);
  catalog->plane_depth = SWAP (catalog->file_ptr->plane_depth);

  /* The file contains two versions of the pointer tables.  Pick the
     right one for the local byte order.  */
#if __BYTE_ORDER == __LITTLE_ENDIAN
  catalog->name_ptr = &catalog->file_ptr->name_ptr[0];
#elif __BYTE_ORDER == __BIG_ENDIAN
  catalog->name_ptr = &catalog->file_ptr->name_ptr[catalog->plane_size
						  * catalog->plane_depth
						  * 3];
#else
# error Cannot handle __BYTE_ORDER byte order
#endif

  /* The rest of the file contains all the strings.  They are
     addressed relative to the position of the first string.  */
  catalog->strings =
    (const char *) &catalog->file_ptr->name_ptr[catalog->plane_size
					       * catalog->plane_depth * 3 * 2];

  /* Determine the largest string offset mentioned in the table.  */
  max_offset = 0;
  tab_size = 3 * catalog->plane_size * catalog->plane_depth;
  for (cnt = 2; cnt < tab_size; cnt += 3)
    if (catalog->name_ptr[cnt] > max_offset)
      max_offset = catalog->name_ptr[cnt];

  /* Now we can check whether the file is large enough to contain the
     tables it says it contains.  */
  if (st.st_size <= (sizeof (struct catalog_obj) + 2 * tab_size + max_offset))
    /* The last string is not contained in the file.  */
    goto invalid_file;

  lastp = catalog->strings + max_offset;
  max_offset = (st.st_size
		- sizeof (struct catalog_obj) + 2 * tab_size + max_offset);
  while (*lastp != '\0')
    {
      if (--max_offset == 0)
	goto invalid_file;
      ++lastp;
    }

  /* Release the lock again.  */
 unlock_return:
  if (fd != -1)
    __close (fd);
  __libc_lock_unlock (catalog->lock);
}