source: vendor/texinfo/4.8/intl/localcharset.c@ 2617

Last change on this file since 2617 was 2617, checked in by bird, 20 years ago

GNU Texinfo 4.8

File size: 10.2 KB
RevLine 
[2617]1/* Determine a canonical name for the current locale's character encoding.
2
3 Copyright (C) 2000-2003 Free Software Foundation, Inc.
4
5 This program is free software; you can redistribute it and/or modify it
6 under the terms of the GNU Library General Public License as published
7 by the Free Software Foundation; either version 2, or (at your option)
8 any later version.
9
10 This program 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.
14
15 You should have received a copy of the GNU Library General Public
16 License along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
18 USA. */
19
20/* Written by Bruno Haible <[email protected]>. */
21
22#ifdef HAVE_CONFIG_H
23# include <config.h>
24#endif
25
26/* Specification. */
27#include "localcharset.h"
28
29#if HAVE_STDDEF_H
30# include <stddef.h>
31#endif
32
33#include <stdio.h>
34#if HAVE_STRING_H
35# include <string.h>
36#else
37# include <strings.h>
38#endif
39#if HAVE_STDLIB_H
40# include <stdlib.h>
41#endif
42
43#if defined _WIN32 || defined __WIN32__
44# undef WIN32 /* avoid warning on mingw32 */
45# define WIN32
46#endif
47
48#if defined __EMX__
49/* Assume EMX program runs on OS/2, even if compiled under DOS. */
50# define OS2
51#endif
52
53#if !defined WIN32
54# if HAVE_LANGINFO_CODESET
55# include <langinfo.h>
56# else
57# if HAVE_SETLOCALE
58# include <locale.h>
59# endif
60# endif
61#elif defined WIN32
62# define WIN32_LEAN_AND_MEAN
63# include <windows.h>
64#endif
65#if defined OS2
66# define INCL_DOS
67# include <os2.h>
68#endif
69
70#if ENABLE_RELOCATABLE
71# include "relocatable.h"
72#else
73# define relocate(pathname) (pathname)
74#endif
75
76#if defined _WIN32 || defined __WIN32__ || defined __EMX__ || defined __DJGPP__
77 /* Win32, OS/2, DOS */
78# define ISSLASH(C) ((C) == '/' || (C) == '\\')
79#endif
80
81#ifndef DIRECTORY_SEPARATOR
82# define DIRECTORY_SEPARATOR '/'
83#endif
84
85#ifndef ISSLASH
86# define ISSLASH(C) ((C) == DIRECTORY_SEPARATOR)
87#endif
88
89#if HAVE_DECL_GETC_UNLOCKED
90# undef getc
91# define getc getc_unlocked
92#endif
93
94/* The following static variable is declared 'volatile' to avoid a
95 possible multithread problem in the function get_charset_aliases. If we
96 are running in a threaded environment, and if two threads initialize
97 'charset_aliases' simultaneously, both will produce the same value,
98 and everything will be ok if the two assignments to 'charset_aliases'
99 are atomic. But I don't know what will happen if the two assignments mix. */
100#if __STDC__ != 1
101# define volatile /* empty */
102#endif
103/* Pointer to the contents of the charset.alias file, if it has already been
104 read, else NULL. Its format is:
105 ALIAS_1 '\0' CANONICAL_1 '\0' ... ALIAS_n '\0' CANONICAL_n '\0' '\0' */
106static const char * volatile charset_aliases;
107
108/* Return a pointer to the contents of the charset.alias file. */
109static const char *
110get_charset_aliases ()
111{
112 const char *cp;
113
114 cp = charset_aliases;
115 if (cp == NULL)
116 {
117#if !(defined VMS || defined WIN32)
118 FILE *fp;
119 const char *dir = relocate (LIBDIR);
120 const char *base = "charset.alias";
121 char *file_name;
122
123 /* Concatenate dir and base into freshly allocated file_name. */
124 {
125 size_t dir_len = strlen (dir);
126 size_t base_len = strlen (base);
127 int add_slash = (dir_len > 0 && !ISSLASH (dir[dir_len - 1]));
128 file_name = (char *) malloc (dir_len + add_slash + base_len + 1);
129 if (file_name != NULL)
130 {
131 memcpy (file_name, dir, dir_len);
132 if (add_slash)
133 file_name[dir_len] = DIRECTORY_SEPARATOR;
134 memcpy (file_name + dir_len + add_slash, base, base_len + 1);
135 }
136 }
137
138 if (file_name == NULL || (fp = fopen (file_name, "r")) == NULL)
139 /* Out of memory or file not found, treat it as empty. */
140 cp = "";
141 else
142 {
143 /* Parse the file's contents. */
144 int c;
145 char buf1[50+1];
146 char buf2[50+1];
147 char *res_ptr = NULL;
148 size_t res_size = 0;
149 size_t l1, l2;
150
151 for (;;)
152 {
153 c = getc (fp);
154 if (c == EOF)
155 break;
156 if (c == '\n' || c == ' ' || c == '\t')
157 continue;
158 if (c == '#')
159 {
160 /* Skip comment, to end of line. */
161 do
162 c = getc (fp);
163 while (!(c == EOF || c == '\n'));
164 if (c == EOF)
165 break;
166 continue;
167 }
168 ungetc (c, fp);
169 if (fscanf (fp, "%50s %50s", buf1, buf2) < 2)
170 break;
171 l1 = strlen (buf1);
172 l2 = strlen (buf2);
173 if (res_size == 0)
174 {
175 res_size = l1 + 1 + l2 + 1;
176 res_ptr = (char *) malloc (res_size + 1);
177 }
178 else
179 {
180 res_size += l1 + 1 + l2 + 1;
181 res_ptr = (char *) realloc (res_ptr, res_size + 1);
182 }
183 if (res_ptr == NULL)
184 {
185 /* Out of memory. */
186 res_size = 0;
187 break;
188 }
189 strcpy (res_ptr + res_size - (l2 + 1) - (l1 + 1), buf1);
190 strcpy (res_ptr + res_size - (l2 + 1), buf2);
191 }
192 fclose (fp);
193 if (res_size == 0)
194 cp = "";
195 else
196 {
197 *(res_ptr + res_size) = '\0';
198 cp = res_ptr;
199 }
200 }
201
202 if (file_name != NULL)
203 free (file_name);
204
205#else
206
207# if defined VMS
208 /* To avoid the troubles of an extra file charset.alias_vms in the
209 sources of many GNU packages, simply inline the aliases here. */
210 /* The list of encodings is taken from the OpenVMS 7.3-1 documentation
211 "Compaq C Run-Time Library Reference Manual for OpenVMS systems"
212 section 10.7 "Handling Different Character Sets". */
213 cp = "ISO8859-1" "\0" "ISO-8859-1" "\0"
214 "ISO8859-2" "\0" "ISO-8859-2" "\0"
215 "ISO8859-5" "\0" "ISO-8859-5" "\0"
216 "ISO8859-7" "\0" "ISO-8859-7" "\0"
217 "ISO8859-8" "\0" "ISO-8859-8" "\0"
218 "ISO8859-9" "\0" "ISO-8859-9" "\0"
219 /* Japanese */
220 "eucJP" "\0" "EUC-JP" "\0"
221 "SJIS" "\0" "SHIFT_JIS" "\0"
222 "DECKANJI" "\0" "DEC-KANJI" "\0"
223 "SDECKANJI" "\0" "EUC-JP" "\0"
224 /* Chinese */
225 "eucTW" "\0" "EUC-TW" "\0"
226 "DECHANYU" "\0" "DEC-HANYU" "\0"
227 "DECHANZI" "\0" "GB2312" "\0"
228 /* Korean */
229 "DECKOREAN" "\0" "EUC-KR" "\0";
230# endif
231
232# if defined WIN32
233 /* To avoid the troubles of installing a separate file in the same
234 directory as the DLL and of retrieving the DLL's directory at
235 runtime, simply inline the aliases here. */
236
237 cp = "CP936" "\0" "GBK" "\0"
238 "CP1361" "\0" "JOHAB" "\0"
239 "CP20127" "\0" "ASCII" "\0"
240 "CP20866" "\0" "KOI8-R" "\0"