Mon Dec 2 15:32:15 1996 Ulrich Drepper <drepper@cygnus.com>
[glibc.git] / catgets / open_catalog.c
blob5335b433c74dd1fbd08a1fc5d893fb823612d360
1 /* Copyright (C) 1996 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper, <drepper@gnu.ai.mit.edu>.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
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 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
20 #include <endian.h>
21 #include <fcntl.h>
22 #include <string.h>
23 #include <stdlib.h>
24 #include <unistd.h>
25 #include <sys/mman.h>
26 #include <sys/stat.h>
28 #include "catgetsinfo.h"
31 #define SWAPU32(w) \
32 (((w) << 24) | (((w) & 0xff00) << 8) | (((w) >> 8) & 0xff00) | ((w) >> 24))
35 void
36 __open_catalog (__nl_catd catalog, int with_path)
38 int fd;
39 struct stat st;
40 int swapping;
42 if (strchr (catalog->cat_name, '/') != NULL || !with_path)
43 fd = open (catalog->cat_name, O_RDONLY);
44 else
46 const char *run_nlspath = catalog->nlspath;
47 #define ENOUGH(n) \
48 if (bufact + (n) >=bufmax) \
49 { \
50 char *old_buf = buf; \
51 bufmax += 256 + (n); \
52 buf = (char *) alloca (bufmax); \
53 memcpy (buf, old_buf, bufact); \
56 /* The RUN_NLSPATH variable contains a colon separated list of
57 descriptions where we expect to find catalogs. We have to
58 recognize certain % substitutions and stop when we found the
59 first existing file. */
60 char *buf;
61 size_t bufact;
62 size_t bufmax;
64 buf = NULL;
65 bufmax = 0;
67 fd = -1;
68 while (*run_nlspath != '\0')
70 bufact = 0;
71 while (*run_nlspath != ':' && *run_nlspath != '\0')
72 if (*run_nlspath == '%')
74 const char *tmp;
76 ++run_nlspath; /* We have seen the `%'. */
77 switch (*run_nlspath++)
79 case 'N':
80 /* Use the catalog name. */
81 ENOUGH (strlen (catalog->cat_name));
82 bufact = __stpcpy (&buf[bufact], catalog->cat_name) - buf;
83 break;
84 case 'L':
85 /* Use the current locale category value. */
86 ENOUGH (strlen (catalog->env_var));
87 bufact = __stpcpy (&buf[bufact], catalog->env_var) - buf;
88 break;
89 case 'l':
90 /* Use language element of locale category value. */
91 tmp = catalog->env_var;
94 ENOUGH (1);
95 buf[bufact++] = *tmp++;
97 while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
98 break;
99 case 't':
100 /* Use territory element of locale category value. */
101 tmp = catalog->env_var;
103 ++tmp;
104 while (*tmp != '\0' && *tmp != '_' && *tmp != '.');
105 if (*tmp == '_')
107 ++tmp;
110 ENOUGH (1);
111 buf[bufact++] = *tmp;
113 while (*tmp != '\0' && *tmp != '.');
115 break;
116 case 'c':
117 /* Use code set element of locale category value. */
118 tmp = catalog->env_var;
120 ++tmp;
121 while (*tmp != '\0' && *tmp != '.');
122 if (*tmp == '.')
124 ++tmp;
127 ENOUGH (1);
128 buf[bufact++] = *tmp;
130 while (*tmp != '\0');
132 break;
133 case '%':
134 ENOUGH (1);
135 buf[bufact++] = '%';
136 break;
137 default:
138 /* Unknown variable: ignore this path element. */
139 bufact = 0;
140 while (*run_nlspath != '\0' && *run_nlspath != ':')
141 ++run_nlspath;
142 break;
145 else
147 ENOUGH (1);
148 buf[bufact++] = *run_nlspath++;
150 ENOUGH (1);
151 buf[bufact] = '\0';
153 if (bufact != 0)
155 fd = __open (buf, O_RDONLY);
156 if (fd >= 0)
157 break;
160 ++run_nlspath;
164 if (fd < 0 || __fstat (fd, &st) < 0)
166 catalog->status = nonexisting;
167 return;
170 #ifndef MAP_COPY
171 /* Linux seems to lack read-only copy-on-write. */
172 #define MAP_COPY MAP_PRIVATE
173 #endif
174 #ifndef MAP_FILE
175 /* Some systems do not have this flag; it is superfluous. */
176 #define MAP_FILE 0
177 #endif
178 #ifndef MAP_INHERIT
179 /* Some systems might lack this; they lose. */
180 #define MAP_INHERIT 0
181 #endif
182 catalog->file_size = st.st_size;
183 catalog->file_ptr =
184 (struct catalog_obj *) __mmap (NULL, st.st_size, PROT_READ,
185 MAP_FILE|MAP_COPY|MAP_INHERIT, fd, 0);
186 if (catalog->file_ptr != (struct catalog_obj *) -1)
187 /* Tell the world we managed to mmap the file. */
188 catalog->status = mmaped;
189 else
191 /* mmap failed perhaps because the system call is not
192 implemented. Try to load the file. */
193 size_t todo;
194 catalog->file_ptr = malloc (st.st_size);
195 if (catalog->file_ptr == NULL)
197 catalog->status = nonexisting;
198 return;
200 todo = st.st_size;
201 /* Save read, handle partial reads. */
204 size_t now = __read (fd, (((char *) &catalog->file_ptr)
205 + (st.st_size - todo)), todo);
206 if (now == 0)
208 free ((void *) catalog->file_ptr);
209 catalog->status = nonexisting;
210 return;
212 todo -= now;
214 while (todo > 0);
215 catalog->status = malloced;
218 /* We don't need the file anymore. */
219 __close (fd);
221 /* Determine whether the file is a catalog file and if yes whether
222 it is written using the correct byte order. Else we have to swap
223 the values. */
224 if (catalog->file_ptr->magic == CATGETS_MAGIC)
225 swapping = 0;
226 else if (catalog->file_ptr->magic == SWAPU32 (CATGETS_MAGIC))
227 swapping = 1;
228 else
230 /* Illegal file. Free he resources and mark catalog as not
231 usable. */
232 if (catalog->status == mmaped)
233 __munmap ((void *) catalog->file_ptr, catalog->file_size);
234 else
235 free (catalog->file_ptr);
236 catalog->status = nonexisting;
237 return;
240 #define SWAP(x) (swapping ? SWAPU32 (x) : (x))
242 /* Get dimensions of the used hashing table. */
243 catalog->plane_size = SWAP (catalog->file_ptr->plane_size);
244 catalog->plane_depth = SWAP (catalog->file_ptr->plane_depth);
246 /* The file contains two versions of the pointer tables. Pick the
247 right one for the local byte order. */
248 #if __BYTE_ORDER == __LITTLE_ENDIAN
249 catalog->name_ptr = &catalog->file_ptr->name_ptr[0];
250 #elif __BYTE_ORDER == __BIG_ENDIAN
251 catalog->name_ptr = &catalog->file_ptr->name_ptr[catalog->plane_size
252 * catalog->plane_depth
253 * 3];
254 #else
255 # error Cannot handle __BYTE_ORDER byte order
256 #endif
258 /* The rest of the file contains all the strings. They are
259 addressed relative to the position of the first string. */
260 catalog->strings =
261 (const char *) &catalog->file_ptr->name_ptr[catalog->plane_size
262 * catalog->plane_depth * 3 * 2];