sync with sylpheed 0.6.3 release
[claws.git] / src / codeconv.c
1 /*
2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
3  * Copyright (C) 1999-2001 Hiroyuki Yamamoto
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) 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
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18  */
19
20 #ifdef HAVE_CONFIG_H
21 #  include "config.h"
22 #endif
23
24 #include <glib.h>
25 #include <string.h>
26 #include <ctype.h>
27 #include <stdlib.h>
28
29 #if (HAVE_WCTYPE_H && HAVE_WCHAR_H)
30 #  include <wchar.h>
31 #  include <wctype.h>
32 #endif
33
34 #if HAVE_LOCALE_H
35 #  include <locale.h>
36 #endif
37
38 #if HAVE_LIBJCONV
39 #  include <jconv.h>
40 #endif
41
42 #include <kcc.h>
43
44 #include "intl.h"
45 #include "codeconv.h"
46 #include "unmime.h"
47 #include "base64.h"
48 #include "utils.h"
49 #include "prefs_common.h"
50
51 #define iskanji(c) \
52         (((c) & 0xff) >= 0xa1 && ((c) & 0xff) <= 0xfe)
53 #define iseucss(c) \
54         (((c) & 0xff) == 0x8e || ((c) & 0xff) == 0x8f)
55 #define isunprintablekanji(c) \
56         (((c) & 0xff) >= 0xa9 && ((c) & 0xff) <= 0xaf)
57
58 void conv_jistoeuc(gchar *outbuf, gint outlen, const gchar *inbuf)
59 {
60         KCC_filter(outbuf, "EUC", (gchar *)inbuf, "JISBB", 0, 0, 0);
61 }
62
63 void conv_euctojis(gchar *outbuf, gint outlen, const gchar *inbuf)
64 {
65         size_t inlen, len;
66
67         inlen = strlen(inbuf);
68         if (iskanji(inbuf[inlen - 1]) || iseucss(inbuf[inlen - 1])) {
69                 /* if tail end of the string is not ended with ascii,
70                    add dummy return code. */
71                 gchar *tmpin, *tmpout;
72
73                 /* length of original string + '\n' + '\0' */
74                 tmpin = alloca(inlen + 2);
75                 if (tmpin == NULL) {
76                         g_warning(_("can't allocate memory\n"));
77                         KCC_filter(outbuf, "JISBB", (gchar *)inbuf, "EUC",
78                                    0, 0, 0);
79                         return;
80                 }
81                 strcpy(tmpin, inbuf);
82                 tmpin[inlen] = '\n';
83                 tmpin[inlen + 1] = '\0';
84
85                 tmpout = alloca(outlen + 1);
86                 if (tmpout == NULL) {
87                         g_warning(_("can't allocate memory\n"));
88                         KCC_filter(outbuf, "JISBB", (gchar *)inbuf, "EUC",
89                                    0, 0, 0);
90                         return;
91                 }
92
93                 KCC_filter(tmpout, "JISBB", tmpin, "EUC", 0, 0, 0);
94                 len = strlen(tmpout);
95                 if (tmpout[len - 1] == '\n')
96                         tmpout[len - 1] = '\0';
97                 strncpy2(outbuf, tmpout, outlen);
98         } else
99                 KCC_filter(outbuf, "JISBB", (gchar *)inbuf, "EUC", 0, 0, 0);
100 }
101
102 void conv_sjistoeuc(gchar *outbuf, gint outlen, const gchar *inbuf)
103 {
104         KCC_filter(outbuf, "EUC", (gchar *)inbuf, "SJIS", 0, 0, 0);
105 }
106
107 void conv_anytoeuc(gchar *outbuf, gint outlen, const gchar *inbuf)
108 {
109         KCC_filter(outbuf, "EUC", (gchar *)inbuf, "AUTO", 0, 0, 0);
110 }
111
112 void conv_anytojis(gchar *outbuf, gint outlen, const gchar *inbuf)
113 {
114         KCC_filter(outbuf, "JISBB", (gchar *)inbuf, "AUTO", 0, 0, 0);
115 }
116
117 #define SUBST_CHAR      '_'
118
119 void conv_unreadable_eucjp(gchar *str)
120 {
121         register guchar *p = str;
122
123         while (*p != '\0') {
124                 if (isascii(*p)) {
125                         /* convert CR+LF -> LF */
126                         if (*p == '\r' && *(p + 1) == '\n')
127                                 memmove(p, p + 1, strlen(p));
128                         /* printable 7 bit code */
129                         p++;
130                 } else if (iskanji(*p)) {
131                         if (iskanji(*(p + 1)) && !isunprintablekanji(*p))
132                                 /* printable euc-jp code */
133                                 p += 2;
134                         else {
135                                 /* substitute unprintable code */
136                                 *p++ = SUBST_CHAR;
137                                 if (*p != '\0') {
138                                         if (isascii(*p))
139                                                 p++;
140                                         else
141                                                 *p++ = SUBST_CHAR;
142                                 }
143                         }
144                 } else if (iseucss(*p)) {
145                         if ((*(p + 1) & 0x80) != 0)
146                                 /* euc-jp hankaku kana */
147                                 p += 2;
148                         else
149                                 *p++ = SUBST_CHAR;
150                 } else
151                         /* substitute unprintable 1 byte code */
152                         *p++ = SUBST_CHAR;
153         }
154 }
155
156 void conv_unreadable_8bit(gchar *str)
157 {
158         register guchar *p = str;
159
160         while (*p != '\0') {
161                 /* convert CR+LF -> LF */
162                 if (*p == '\r' && *(p + 1) == '\n')
163                         memmove(p, p + 1, strlen(p));
164                 else if (!isascii(*p)) *p = SUBST_CHAR;
165                 p++;
166         }
167 }
168
169 void conv_unreadable_latin(gchar *str)
170 {
171         register guchar *p = str;
172
173         while (*p != '\0') {
174                 /* convert CR+LF -> LF */
175                 if (*p == '\r' && *(p + 1) == '\n')
176                         memmove(p, p + 1, strlen(p));
177                 else if ((*p & 0xff) >= 0x80 && (*p & 0xff) <= 0x9f)
178                         *p = SUBST_CHAR;
179                 p++;
180         }
181 }
182
183 #define NCV     '\0'
184
185 void conv_mb_alnum(gchar *str)
186 {
187         static guchar char_tbl[] = {
188                 /* 0xa0 - 0xaf */
189                 NCV, ' ', NCV, NCV, ',', '.', NCV, ':',
190                 ';', '?', '!', NCV, NCV, NCV, NCV, NCV,
191                 /* 0xb0 - 0xbf */
192                 NCV, NCV, NCV, NCV, NCV, NCV, NCV, NCV,
193                 NCV, NCV, NCV, NCV, NCV, NCV, NCV, NCV,
194                 /* 0xc0 - 0xcf */
195                 NCV, NCV, NCV, NCV, NCV, NCV, NCV, NCV,
196                 NCV, NCV, '(', ')', NCV, NCV, '[', ']',
197                 /* 0xd0 - 0xdf */
198                 '{', '}', NCV, NCV, NCV, NCV, NCV, NCV,
199                 NCV, NCV, NCV, NCV, '+', '-', NCV, NCV,
200                 /* 0xe0 - 0xef */
201                 NCV, '=', NCV, '<', '>', NCV, NCV, NCV,
202                 NCV, NCV, NCV, NCV, NCV, NCV, NCV, NCV
203         };
204
205         register guchar *p = str;
206         register gint len;
207
208         len = strlen(str);
209
210         while (len > 1) {
211                 if (*p == 0xa3) {
212                         register guchar ch = *(p + 1);
213
214                         if (ch >= 0xb0 && ch <= 0xfa) {
215                                 /* [a-zA-Z] */
216                                 *p = ch & 0x7f;
217                                 p++;
218                                 len--;
219                                 memmove(p, p + 1, len);
220                                 len--;
221                         } else  {
222                                 p += 2;
223                                 len -= 2;
224                         }
225                 } else if (*p == 0xa1) {
226                         register guchar ch = *(p + 1);
227
228                         if (ch >= 0xa0 && ch <= 0xef &&
229                             NCV != char_tbl[ch - 0xa0]) {
230                                 *p = char_tbl[ch - 0xa0];
231                                 p++;
232                                 len--;
233                                 memmove(p, p + 1, len);
234                                 len--;
235                         } else {
236                                 p += 2;
237                                 len -= 2;
238                         }
239                 } else if (iskanji(*p)) {
240                         p += 2;
241                         len -= 2;
242                 } else {
243                         p++;
244                         len--;
245                 }
246         }
247 }
248
249 void conv_jistodisp(gchar *outbuf, gint outlen, const gchar *inbuf)
250 {
251         conv_jistoeuc(outbuf, outlen, inbuf);
252         conv_unreadable_eucjp(outbuf);
253 }
254
255 void conv_sjistodisp(gchar *outbuf, gint outlen, const gchar *inbuf)
256 {
257         conv_sjistoeuc(outbuf, outlen, inbuf);
258         conv_unreadable_eucjp(outbuf);
259 }
260
261 void conv_euctodisp(gchar *outbuf, gint outlen, const gchar *inbuf)
262 {
263         strncpy2(outbuf, inbuf, outlen);
264         conv_unreadable_eucjp(outbuf);
265 }
266
267 void conv_ustodisp(gchar *outbuf, gint outlen, const gchar *inbuf)
268 {
269         strncpy2(outbuf, inbuf, outlen);
270         conv_unreadable_8bit(outbuf);
271 }
272
273 void conv_latintodisp(gchar *outbuf, gint outlen, const gchar *inbuf)
274 {
275         strncpy2(outbuf, inbuf, outlen);
276         conv_unreadable_latin(outbuf);
277 }
278
279 void conv_noconv(gchar *outbuf, gint outlen, const gchar *inbuf)
280 {
281         strncpy2(outbuf, inbuf, outlen);
282 }
283
284 CodeConverter *conv_code_converter_new(const gchar *charset)
285 {
286         CodeConverter *conv;
287
288         conv = g_new0(CodeConverter, 1);
289 #if !HAVE_LIBJCONV
290         conv->code_conv_func = conv_get_code_conv_func(charset);
291 #endif
292         conv->charset_str = g_strdup(charset);
293         conv->charset = conv_get_charset_from_str(charset);
294
295         return conv;
296 }
297
298 void conv_code_converter_destroy(CodeConverter *conv)
299 {
300         g_free(conv->charset_str);
301         g_free(conv);
302 }
303
304 gint conv_convert(CodeConverter *conv, gchar *outbuf, gint outlen,
305                   const gchar *inbuf)
306 {
307 #if HAVE_LIBJCONV
308         gchar *str;
309
310         str = conv_codeset_strdup(inbuf, conv->charset_str, NULL);
311         if (!str)
312                 return -1;
313         else {
314                 strncpy2(outbuf, str, outlen);
315                 g_free(str);
316         }
317 #else /* !HAVE_LIBJCONV */
318         conv->code_conv_func(outbuf, outlen, inbuf);
319 #endif
320
321         return 0;
322 }
323
324 gchar *conv_codeset_strdup(const gchar *inbuf,
325                            const gchar *src_codeset, const gchar *dest_codeset)
326 {
327         gchar *buf;
328         size_t len;
329 #if HAVE_LIBJCONV
330         gint actual_codeset;
331         const gchar *const *codesets;
332         gint n_codesets;
333 #else /* !HAVE_LIBJCONV */
334         CharSet src_charset = C_AUTO, dest_charset = C_AUTO;
335 #endif
336
337         if (!dest_codeset) {
338                 CodeConvFunc func;
339
340                 func = conv_get_code_conv_func(src_codeset);
341                 if (func != conv_noconv) {
342                         if (func == conv_jistodisp || func == conv_sjistodisp)
343                                 len = strlen(inbuf) * 2 + 1;
344                         else
345                                 len = strlen(inbuf) + 1;
346                         buf = g_malloc(len);
347                         if (!buf) return NULL;
348                         func(buf, len, inbuf);
349                         buf = g_realloc(buf, strlen(buf) + 1);
350                         return buf;
351                 }
352         }
353
354         /* don't convert if src and dest codeset are identical */
355         if (src_codeset && dest_codeset &&
356             !strcasecmp(src_codeset, dest_codeset))
357                 return g_strdup(inbuf);
358
359 #if HAVE_LIBJCONV
360         if (src_codeset) {
361                 codesets = &src_codeset;
362                 n_codesets = 1;
363         } else
364                 codesets = jconv_info_get_pref_codesets(&n_codesets);
365         if (!dest_codeset) {
366                 dest_codeset = conv_get_current_charset_str();
367                 /* don't convert if current codeset is US-ASCII */
368                 if (!strcasecmp(dest_codeset, CS_US_ASCII))
369                         return g_strdup(inbuf);
370         }
371
372         if (jconv_alloc_conv(inbuf, strlen(inbuf), &buf, &len,
373                              codesets, n_codesets,
374                              &actual_codeset, dest_codeset)
375             == 0)
376                 return buf;
377         else
378                 return NULL;
379 #else /* !HAVE_LIBJCONV */
380         if (src_codeset) {
381                 if (!strcasecmp(src_codeset, CS_EUC_JP) ||
382                     !strcasecmp(src_codeset, "EUCJP"))
383                         src_charset = C_EUC_JP;
384                 else if (!strcasecmp(src_codeset, CS_SHIFT_JIS) ||
385                          !strcasecmp(src_codeset, "SHIFT-JIS") ||
386                          !strcasecmp(src_codeset, "SJIS"))
387                         src_charset = C_SHIFT_JIS;
388                 if (dest_codeset && !strcasecmp(dest_codeset, CS_ISO_2022_JP))
389                         dest_charset = C_ISO_2022_JP;
390         }
391
392         if ((src_charset == C_EUC_JP || src_charset == C_SHIFT_JIS) &&
393             dest_charset == C_ISO_2022_JP) {
394                 len = (strlen(inbuf) + 1) * 3;
395                 buf = g_malloc(len);
396                 if (buf) {
397                         if (src_charset == C_EUC_JP)
398                                 conv_euctojis(buf, len, inbuf);
399                         else
400                                 conv_anytojis(buf, len, inbuf);
401                         buf = g_realloc(buf, strlen(buf) + 1);
402                 }
403         } else
404                 buf = g_strdup(inbuf);
405
406         return buf;
407 #endif /* !HAVE_LIBJCONV */
408 }
409
410 CodeConvFunc conv_get_code_conv_func(const gchar *charset)
411 {
412         CodeConvFunc code_conv;
413
414         if (!charset) {
415                 if (conv_get_outgoing_charset() == C_ISO_2022_JP)
416                         return conv_jistodisp;
417                 else
418                         return conv_noconv;
419         }
420
421         if (!strcasecmp(charset, CS_ISO_2022_JP) ||
422             !strcasecmp(charset, CS_ISO_2022_JP_2))
423                 code_conv = conv_jistodisp;
424         else if (!strcasecmp(charset, CS_US_ASCII))
425                 code_conv = conv_ustodisp;
426         else if (!strncasecmp(charset, CS_ISO_8859_1, 10))
427                 code_conv = conv_latintodisp;
428 #if !HAVE_LIBJCONV
429         else if (!strncasecmp(charset, "ISO-8859-", 9))
430                 code_conv = conv_latintodisp;
431 #endif
432         else if (!strcasecmp(charset, CS_SHIFT_JIS) ||
433                  !strcasecmp(charset, "SHIFT-JIS")  ||
434                  !strcasecmp(charset, "SJIS")       ||
435                  !strcasecmp(charset, "X-SJIS"))
436                 code_conv = conv_sjistodisp;
437         else if (!strcasecmp(charset, CS_EUC_JP) ||
438                  !strcasecmp(charset, "EUCJP"))
439                 code_conv = conv_euctodisp;
440         else
441                 code_conv = conv_noconv;
442
443         return code_conv;
444 }
445
446 static const struct {
447         CharSet charset;
448         gchar *const name;
449 } charsets[] = {
450         {C_US_ASCII,            CS_US_ASCII},
451         {C_US_ASCII,            CS_ANSI_X3_4_1968},
452         {C_UTF_8,               CS_UTF_8},
453         {C_ISO_8859_1,          CS_ISO_8859_1},
454         {C_ISO_8859_2,          CS_ISO_8859_2},
455         {C_ISO_8859_4,          CS_ISO_8859_4},
456         {C_ISO_8859_5,          CS_ISO_8859_5},
457         {C_ISO_8859_7,          CS_ISO_8859_7},
458         {C_ISO_8859_8,          CS_ISO_8859_8},
459         {C_ISO_8859_9,          CS_ISO_8859_9},
460         {C_ISO_8859_13,         CS_ISO_8859_13},
461         {C_ISO_8859_15,         CS_ISO_8859_15},
462         {C_BALTIC,              CS_BALTIC},
463         {C_CP1251,              CS_CP1251},
464         {C_WINDOWS_1251,        CS_WINDOWS_1251},
465         {C_KOI8_R,              CS_KOI8_R},
466         {C_KOI8_U,              CS_KOI8_U},
467         {C_ISO_2022_JP,         CS_ISO_2022_JP},
468         {C_ISO_2022_JP_2,       CS_ISO_2022_JP_2},
469         {C_EUC_JP,              CS_EUC_JP},
470         {C_SHIFT_JIS,           CS_SHIFT_JIS},
471         {C_ISO_2022_KR,         CS_ISO_2022_KR},
472         {C_EUC_KR,              CS_EUC_KR},
473         {C_ISO_2022_CN,         CS_ISO_2022_CN},
474         {C_EUC_CN,              CS_EUC_CN},
475         {C_GB2312,              CS_GB2312},
476         {C_EUC_TW,              CS_EUC_TW},
477         {C_BIG5,                CS_BIG5},
478 };
479
480 #if !HAVE_LIBJCONV
481 static const struct {
482         gchar *const locale;
483         CharSet charset;
484 } locale_table[] = {
485         {"ja_JP.eucJP"  , C_EUC_JP},
486         {"ja_JP.ujis"   , C_EUC_JP},
487         {"ja_JP.EUC"    , C_EUC_JP},
488         {"ja_JP.SJIS"   , C_SHIFT_JIS},
489         {"ja_JP.JIS"    , C_ISO_2022_JP},
490         {"ja_JP"        , C_EUC_JP},
491         {"ko_KR"        , C_EUC_KR},
492         {"zh_CN.GB2312" , C_GB2312},
493         {"zh_CN"        , C_GB2312},
494         {"zh_TW.eucTW"  , C_EUC_TW},
495         {"zh_TW.Big5"   , C_BIG5},
496         {"zh_TW"        , C_BIG5},
497
498         {"ru_RU.KOI8-R" , C_KOI8_R},
499         {"ru_RU.CP1251" , C_CP1251},
500
501         {"en_US"        , C_ISO_8859_1},
502         {"ca_ES"        , C_ISO_8859_1},
503         {"da_DK"        , C_ISO_8859_1},
504         {"de_DE"        , C_ISO_8859_1},
505         {"nl_NL"        , C_ISO_8859_1},
506         {"et_EE"        , C_ISO_8859_1},
507         {"fi_FI"        , C_ISO_8859_1},
508         {"fr_FR"        , C_ISO_8859_1},
509         {"is_IS"        , C_ISO_8859_1},
510         {"it_IT"        , C_ISO_8859_1},
511         {"no_NO"        , C_ISO_8859_1},
512         {"pt_PT"        , C_ISO_8859_1},
513         {"pt_BR"        , C_ISO_8859_1},
514         {"es_ES"        , C_ISO_8859_1},
515         {"sv_SE"        , C_ISO_8859_1},
516
517         {"hr_HR"        , C_ISO_8859_2},
518         {"hu_HU"        , C_ISO_8859_2},
519         {"pl_PL"        , C_ISO_8859_2},
520         {"ro_RO"        , C_ISO_8859_2},
521         {"sk_SK"        , C_ISO_8859_2},
522         {"sl_SI"        , C_ISO_8859_2},
523         {"ru_RU"        , C_ISO_8859_5},
524         {"el_GR"        , C_ISO_8859_7},
525         {"iw_IL"        , C_ISO_8859_8},
526         {"tr_TR"        , C_ISO_8859_9},
527
528         {"lt_LT.iso88594"       , C_ISO_8859_4},
529         {"lt_LT.ISO8859-4"      , C_ISO_8859_4},
530         {"lt_LT.ISO_8859-4"     , C_ISO_8859_4},
531         {"lt_LT"                , C_ISO_8859_13},
532         {"lv_LV"                , C_ISO_8859_13},
533
534         {"C"                    , C_US_ASCII},
535         {"POSIX"                , C_US_ASCII},
536         {"ANSI_X3.4-1968"       , C_US_ASCII},
537 };
538 #endif /* !HAVE_LIBJCONV */
539
540 const gchar *conv_get_charset_str(CharSet charset)
541 {
542         gint i;
543
544         for (i = 0; i < sizeof(charsets) / sizeof(charsets[0]); i++) {
545                 if (charsets[i].charset == charset)
546                         return charsets[i].name;
547         }
548
549         return NULL;
550 }
551
552 CharSet conv_get_charset_from_str(const gchar *charset)
553 {
554         gint i;
555
556         if (!charset) return C_AUTO;
557
558         for (i = 0; i < sizeof(charsets) / sizeof(charsets[0]); i++) {
559                 if (!strcasecmp(charsets[i].name, charset))
560                         return charsets[i].charset;
561         }
562
563         return C_AUTO;
564 }
565
566 CharSet conv_get_current_charset(void)
567 {
568         static CharSet cur_charset = -1;
569         gint i;
570
571 #if HAVE_LIBJCONV
572         const gchar *cur_codeset;
573 #else
574         const gchar *cur_locale;
575 #endif
576
577         if (cur_charset != -1)
578                 return cur_charset;
579
580 #if HAVE_LIBJCONV
581         cur_codeset = jconv_info_get_current_codeset();
582         for (i = 0; i < sizeof(charsets) / sizeof(charsets[0]); i++) {
583                 if (!strcasecmp(cur_codeset, charsets[i].name)) {
584                         cur_charset = charsets[i].charset;
585                         return cur_charset;
586                 }
587         }
588 #else
589         cur_locale = g_getenv("LC_ALL");
590         if (!cur_locale) cur_locale = g_getenv("LC_CTYPE");
591         if (!cur_locale) cur_locale = g_getenv("LANG");
592         if (!cur_locale) cur_locale = setlocale(LC_CTYPE, NULL);
593
594         debug_print("current locale: %s\n",
595                     cur_locale ? cur_locale : "(none)");
596
597         if (!cur_locale) {
598                 cur_charset = C_US_ASCII;
599                 return cur_charset;
600         }
601
602         if (strcasestr(cur_locale, "UTF-8")) {
603                 cur_charset = C_UTF_8;
604                 return cur_charset;
605         }
606
607         for (i = 0; i < sizeof(locale_table) / sizeof(locale_table[0]); i++) {
608                 const gchar *p;
609
610                 /* "ja_JP.EUC" matches with "ja_JP.eucJP" and "ja_JP.EUC" */
611                 /* "ja_JP" matches with "ja_JP.xxxx" and "ja" */
612                 if (!strncasecmp(cur_locale, locale_table[i].locale,
613                                  strlen(locale_table[i].locale))) {
614                         cur_charset = locale_table[i].charset;
615                         return cur_charset;
616                 } else if ((p = strchr(locale_table[i].locale, '_')) &&
617                          !strchr(p + 1, '.')) {
618                         if (strlen(cur_locale) == 2 &&
619                             !strncasecmp(cur_locale, locale_table[i].locale, 2)) {
620                                 cur_charset = locale_table[i].charset;
621                                 return cur_charset;
622                         }
623                 }
624         }
625 #endif
626
627         cur_charset = C_AUTO;
628         return cur_charset;
629 }
630
631 const gchar *conv_get_current_charset_str(void)
632 {
633         static const gchar *codeset = NULL;
634
635         if (!codeset)
636                 codeset = conv_get_charset_str(conv_get_current_charset());
637
638         return codeset ? codeset : "US-ASCII";
639 }
640
641 CharSet conv_get_outgoing_charset(void)
642 {
643         static CharSet out_charset = -1;
644
645 #if HAVE_LIBJCONV
646         gint i, j, n_pref_codesets;
647         const gchar *const *pref_codesets;
648 #else
649         CharSet cur_charset;
650 #endif
651
652         if (out_charset != -1)
653                 return out_charset;
654
655 #if HAVE_LIBJCONV
656         /* skip US-ASCII and UTF-8 */
657         pref_codesets = jconv_info_get_pref_codesets(&n_pref_codesets);
658         for (i = 0; i < n_pref_codesets; i++) {
659                 for (j = 3; j < sizeof(charsets) / sizeof(charsets[0]); j++) {
660                         if (!strcasecmp(pref_codesets[i], charsets[j].name)) {
661                                 out_charset = charsets[j].charset;
662                                 return out_charset;
663                         }
664                 }
665         }
666
667         for (i = 0; i < n_pref_codesets; i++) {
668                 if (!strcasecmp(pref_codesets[i], "UTF-8")) {
669                         out_charset = C_UTF_8;
670                         return out_charset;
671                 }
672         }
673
674         out_charset = C_AUTO;
675 #else
676         cur_charset = conv_get_current_charset();
677         switch (cur_charset) {
678         case C_EUC_JP:
679         case C_SHIFT_JIS:
680                 out_charset = C_ISO_2022_JP;
681                 break;
682         default:
683                 out_charset = cur_charset;
684         }
685 #endif
686
687         return out_charset;
688 }
689
690 const gchar *conv_get_outgoing_charset_str(void)
691 {
692         CharSet out_charset;
693         const gchar *str;
694
695         if (prefs_common.outgoing_charset) {
696                 if (!isalpha(prefs_common.outgoing_charset[0])) {
697                         g_free(prefs_common.outgoing_charset);
698                         prefs_common.outgoing_charset = g_strdup(CS_AUTO);
699                 } else if (strcmp(prefs_common.outgoing_charset, CS_AUTO) != 0)
700                         return prefs_common.outgoing_charset;
701         }
702
703         out_charset = conv_get_outgoing_charset();
704         str = conv_get_charset_str(out_charset);
705
706         return str ? str : "US-ASCII";
707 }
708
709 const gchar *conv_get_current_locale(void)
710 {
711         gchar *cur_locale;
712
713         cur_locale = g_getenv("LC_ALL");
714         if (!cur_locale) cur_locale = g_getenv("LANG");
715         if (!cur_locale) cur_locale = setlocale(LC_CTYPE, NULL);
716
717         debug_print("current locale: %s\n",
718                     cur_locale ? cur_locale : "(none)");
719
720         return cur_locale;
721 }
722
723 void conv_unmime_header_overwrite(gchar *str)
724 {
725         gchar *buf;
726         gint outlen;
727         CharSet cur_charset;
728
729         cur_charset = conv_get_current_charset();
730
731 #if HAVE_LIBJCONV
732         Xstrdup_a(buf, str, return);
733         outlen = strlen(str) + 1;
734         UnMimeHeaderConv(buf, str, outlen);
735         if (cur_charset == C_EUC_JP) {
736                 gchar *tmp;
737                 gint len;
738
739                 len = strlen(str) * 2 + 1;
740                 Xalloca(tmp, len, return);
741                 conv_jistodisp(tmp, len, str);
742                 strncpy2(str, tmp, outlen);
743         }
744 #else
745         if (cur_charset == C_EUC_JP) {
746                 gchar *tmp;
747                 gint len;
748
749                 Xstrdup_a(buf, str, return);
750                 outlen = strlen(str) + 1;
751                 UnMimeHeader(buf);
752                 len = strlen(buf) * 2 + 1;
753                 Xalloca(tmp, len, {strncpy2(str, buf, outlen); return;});
754                 conv_jistodisp(tmp, len, buf);
755                 strncpy2(str, tmp, outlen);
756         } else
757                 UnMimeHeader(str);
758 #endif
759 }
760
761 void conv_unmime_header(gchar *outbuf, gint outlen, const gchar *str,
762                         const gchar *charset)
763 {
764         gchar *buf;
765         CharSet cur_charset;
766
767         cur_charset = conv_get_current_charset();
768         Xstrdup_a(buf, str, return);
769
770 #if HAVE_LIBJCONV
771         UnMimeHeaderConv(buf, outbuf, outlen);
772 #else
773         UnMimeHeader(buf);
774         strncpy2(outbuf, buf, outlen);
775 #endif
776         if (cur_charset == C_EUC_JP) {
777                 gint len;
778
779                 len = strlen(outbuf) * 2 + 1;
780                 Xalloca(buf, len, return);
781                 conv_jistodisp(buf, len, outbuf);
782                 strncpy2(outbuf, buf, outlen);
783         }
784 }
785
786 #define MAX_ENCLEN      75
787 #define MAX_LINELEN     76
788
789 #define B64LEN(len)     ((len) / 3 * 4 + ((len) % 3 ? 4 : 0))
790
791 #if HAVE_LIBJCONV
792 void conv_encode_header(gchar *dest, gint len, const gchar *src,
793                         gint header_len)
794 {
795         wchar_t *wsrc;
796         wchar_t *wsrcp;
797         gchar *destp;
798         size_t line_len, mimehdr_len, mimehdr_begin_len;
799         gchar *mimehdr_init = "=?";
800         gchar *mimehdr_end = "?=";
801         gchar *mimehdr_enctype = "?B?";
802         const gchar *mimehdr_charset;
803
804         /* g_print("src = %s\n", src); */
805         mimehdr_charset = conv_get_outgoing_charset_str();
806
807         /* convert to wide-character string */
808         wsrcp = wsrc = strdup_mbstowcs(src);
809
810         mimehdr_len = strlen(mimehdr_init) + strlen(mimehdr_end) +
811                 strlen(mimehdr_charset) + strlen(mimehdr_enctype);
812         mimehdr_begin_len = strlen(mimehdr_init) +
813                 strlen(mimehdr_charset) + strlen(mimehdr_enctype);
814         /* line_len = 1; */
815         line_len = header_len;
816         destp = dest;
817         *dest = '\0';
818
819         g_return_if_fail(wsrc != NULL);
820
821         while (*wsrcp) {
822                 wchar_t *wp, *wtmp, *wtmpp;
823                 gint nspc = 0;
824
825                 /* irresponsible buffer overrun check */
826                 if ((len - (destp - dest)) < (MAX_LINELEN + 1) * 2) break;
827
828                 /* encode string including space
829                    if non-ASCII string follows */
830                 if (is_next_nonascii(wsrcp)) {
831                         wp = wsrcp;
832                         while ((wp = find_wspace(wp)) != NULL)
833                                 if (!is_next_nonascii(wp)) break;
834                 } else
835                         wp = find_wspace(wsrcp);
836
837                 if (wp != NULL) {
838                         wtmp = wcsndup(wsrcp, wp - wsrcp);
839                         wsrcp = wp + 1;
840                         while (iswspace(wsrcp[nspc])) nspc++;
841                 } else {
842                         wtmp = wcsdup(wsrcp);
843                         wsrcp += wcslen(wsrcp);
844                 }
845
846                 wtmpp = wtmp;
847
848                 do {
849                         gint tlen = 0, str_ascii = 1;
850                         gchar *tmp; /* internal codeset */
851                         gchar *raw; /* converted, but not base64 encoded */
852                         register gchar *tmpp;
853                         gint raw_len;
854
855                         tmpp = tmp = g_malloc(wcslen(wtmpp) * MB_CUR_MAX + 1);
856                         *tmp = '\0';
857                         raw = g_strdup("");
858                         raw_len = 0;
859
860                         while (*wtmpp != (wchar_t)0) {
861                                 gint mbl;
862                                 gint dummy;
863                                 gchar *raw_new = NULL;
864                                 int raw_new_len = 0;
865                                 const gchar *src_codeset;
866
867                                 if (*wtmpp < 32 || *wtmpp >= 127)
868                                         str_ascii = 0;
869                                 mbl = wctomb(tmpp, *wtmpp);
870                                 if (mbl == -1) {
871                                         g_warning("invalid wide character\n");
872                                         wtmpp++;
873                                         continue;
874                                 }
875                                 /* g_free(raw); */
876                                 src_codeset = conv_get_current_charset_str();
877                                 /* printf ("tmp = %s, tlen = %d, mbl\n", 
878                                         tmp, tlen, mbl); */
879                                 if (jconv_alloc_conv(tmp, tlen + mbl,
880                                                      &raw_new, &raw_new_len,
881                                                      &src_codeset, 1,
882                                                      &dummy, mimehdr_charset)
883                                     != 0) {
884                                         g_warning("can't convert\n");
885                                         tmpp[0] = '\0';
886                                         continue;
887                                 }
888                                 if (!str_ascii) {
889                                         gint dlen = mimehdr_len +
890                                                 B64LEN(raw_len);
891                                         if ((line_len + dlen +
892                                              (*(wtmpp + 1) ? 0 : nspc) +
893                                              (line_len > 1 ? 1 : 0))
894                                             > MAX_LINELEN) {
895                                                 g_free(raw_new);
896                                                 if (tlen == 0) {
897                                                         *destp++ = '\n';
898                                                         *destp++ = ' ';
899                                                         line_len = 1;
900                                                         str_ascii = 1;
901                                                         continue;
902                                                 } else {
903                                                         *tmpp = '\0';
904                                                         break;
905                                                 }
906                                         }
907                                 } else if ((line_len + tlen + mbl +
908                                             (*(wtmpp + 1) ? 0 : nspc) +
909                                             (line_len > 1 ? 1 : 0))
910                                            > MAX_LINELEN) {
911                                         g_free(raw_new);
912                                         if (1 + tlen + mbl +
913                                             (*(wtmpp + 1) ? 0 : nspc)
914                                             >= MAX_LINELEN) {
915                                                 *tmpp = '\0';
916                                                 break;
917                                         }
918                                         *destp++ = '\n';
919                                         *destp++ = ' ';
920                                         line_len = 1;
921                                         continue;
922                                 }
923
924                                 tmpp += mbl;
925                                 *tmpp = '\0';
926
927                                 tlen += mbl;
928
929                                 g_free(raw);
930                                 raw = raw_new;
931                                 raw_len = raw_new_len;
932
933                                 wtmpp++;
934                         }
935                         /*
936                           g_print("tmp = %s, tlen = %d, mb_seqlen = %d\n",
937                                 tmp, tlen, mb_seqlen);
938                         */                              
939
940                         if (tlen == 0 || raw_len == 0) {
941                                 g_free(tmp);
942                                 g_free(raw);
943                                 continue;
944                         }
945
946                         if (line_len > 1 && destp > dest) {
947                                 *destp++ = ' ';
948                                 *destp = '\0';
949                                 line_len++;
950                         }
951
952                         if (!str_ascii) {
953                                 g_snprintf(destp, len - strlen(dest), "%s%s%s",
954                                            mimehdr_init, mimehdr_charset,
955                                            mimehdr_enctype);
956                                 destp += mimehdr_begin_len;
957                                 line_len += mimehdr_begin_len;
958
959                                 to64frombits(destp, raw, raw_len);
960                                 line_len += strlen(destp);
961                                 destp += strlen(destp);
962
963                                 strcpy(destp, mimehdr_end);
964                                 destp += strlen(mimehdr_end);
965                                 line_len += strlen(mimehdr_end);
966                         } else {
967                                 strcpy(destp, tmp);
968                                 line_len += strlen(destp);
969                                 destp += strlen(destp);
970                         }
971
972                         g_free(tmp);
973                         g_free(raw);
974                         /* g_print("line_len = %d\n\n", line_len); */
975                 } while (*wtmpp != (wchar_t)0);
976
977                 while (iswspace(*wsrcp)) {
978                         gint mbl;
979
980                         mbl = wctomb(destp, *wsrcp++);
981                         if (mbl != -1) {
982                                 destp += mbl;
983                                 line_len += mbl;
984                         }
985                 }
986                 *destp = '\0';
987
988                 g_free(wtmp);
989         }
990
991         g_free(wsrc);
992
993         /* g_print("dest = %s\n", dest);  */
994 }
995 #else /* !HAVE_LIBJCONV */
996
997 #define JIS_SEQLEN      3
998
999 void conv_encode_header(gchar *dest, gint len, const gchar *src,
1000                         gint header_len)
1001 {
1002         wchar_t *wsrc;
1003         wchar_t *wsrcp;
1004         gchar *destp;
1005         size_t line_len, mimehdr_len, mimehdr_begin_len;
1006         gchar *mimehdr_init = "=?";
1007         gchar *mimehdr_end = "?=";
1008         gchar *mimehdr_enctype = "?B?";
1009         const gchar *mimehdr_charset;
1010
1011         /* g_print("src = %s\n", src); */
1012         mimehdr_charset = conv_get_outgoing_charset_str();
1013         if (strcmp(mimehdr_charset, "ISO-2022-JP") != 0) {
1014                 /* currently only supports Japanese */
1015                 strncpy2(dest, src, len);
1016                 return;
1017         }
1018
1019         /* convert to wide-character string */
1020         wsrcp = wsrc = strdup_mbstowcs(src);
1021
1022         mimehdr_len = strlen(mimehdr_init) + strlen(mimehdr_end) +
1023                       strlen(mimehdr_charset) + strlen(mimehdr_enctype);
1024         mimehdr_begin_len = strlen(mimehdr_init) +
1025                             strlen(mimehdr_charset) + strlen(mimehdr_enctype);
1026         /* line_len = 1; */
1027         line_len = header_len;
1028         destp = dest;
1029         *dest = '\0';
1030
1031         g_return_if_fail(wsrc != NULL);
1032
1033         while (*wsrcp) {
1034                 wchar_t *wp, *wtmp, *wtmpp;
1035                 gint nspc = 0;
1036
1037                 /* irresponsible buffer overrun check */
1038                 if ((len - (destp - dest)) < (MAX_LINELEN + 1) * 2) break;
1039
1040                 /* encode string including space
1041                    if non-ASCII string follows */
1042                 if (is_next_nonascii(wsrcp)) {
1043                         wp = wsrcp;
1044                         while ((wp = find_wspace(wp)) != NULL)
1045                                 if (!is_next_nonascii(wp)) break;
1046                 } else
1047                         wp = find_wspace(wsrcp);
1048
1049                 if (wp != NULL) {
1050                         wtmp = wcsndup(wsrcp, wp - wsrcp);
1051                         wsrcp = wp + 1;
1052                         while (iswspace(wsrcp[nspc])) nspc++;
1053                 } else {
1054                         wtmp = wcsdup(wsrcp);
1055                         wsrcp += wcslen(wsrcp);
1056                 }
1057
1058                 wtmpp = wtmp;
1059
1060                 do {
1061                         gint prev_mbl = 1, tlen = 0, mb_seqlen = 0;
1062                         gchar *tmp;
1063                         register gchar *tmpp;
1064
1065                         tmpp = tmp = g_malloc(wcslen(wtmpp) * MB_CUR_MAX + 1);
1066                         *tmp = '\0';
1067
1068                         while (*wtmpp != (wchar_t)0) {
1069                                 gint mbl;
1070
1071                                 mbl = wctomb(tmpp, *wtmpp);
1072                                 if (mbl == -1) {
1073                                         g_warning("invalid wide character\n");
1074                                         wtmpp++;
1075                                         continue;
1076                                 }
1077
1078                                 /* length of KI + KO */
1079                                 if (prev_mbl == 1 && mbl == 2)
1080                                         mb_seqlen += JIS_SEQLEN * 2;
1081
1082                                 if (mb_seqlen) {
1083                                         gint dlen = mimehdr_len +
1084                                                 B64LEN(tlen + mb_seqlen + mbl);
1085
1086                                         if ((line_len + dlen +
1087                                              (*(wtmpp + 1) ? 0 : nspc) +
1088                                              (line_len > 1 ? 1 : 0))
1089                                             > MAX_LINELEN) {
1090                                                 if (tlen == 0) {
1091                                                         *destp++ = '\n';
1092                                                         *destp++ = ' ';
1093                                                         line_len = 1;
1094                                                         mb_seqlen = 0;
1095                                                         continue;
1096                                                 } else {
1097                                                         *tmpp = '\0';
1098                                                         break;
1099                                                 }
1100                                         }
1101                                 } else if ((line_len + tlen + mbl +
1102                                             (*(wtmpp + 1) ? 0 : nspc) +
1103                                             (line_len > 1 ? 1 : 0))
1104                                            > MAX_LINELEN) {
1105                                         if (1 + tlen + mbl +
1106                                             (*(wtmpp + 1) ? 0 : nspc)
1107                                             >= MAX_LINELEN) {
1108                                                 *tmpp = '\0';
1109                                                 break;
1110                                         }
1111                                         *destp++ = '\n';
1112                                         *destp++ = ' ';
1113                                         line_len = 1;
1114                                         continue;
1115                                 }
1116
1117                                 tmpp += mbl;
1118                                 *tmpp = '\0';
1119
1120                                 tlen += mbl;
1121                                 prev_mbl = mbl;
1122
1123                                 wtmpp++;
1124                         }
1125                         /* g_print("tmp = %s, tlen = %d, mb_seqlen = %d\n",
1126                                 tmp, tlen, mb_seqlen);
1127                         */                              
1128
1129                         if (tlen == 0) {
1130                                 g_free(tmp);
1131                                 continue;
1132                         }
1133
1134                         if (line_len > 1 && destp > dest) {
1135                                 *destp++ = ' ';
1136                                 *destp = '\0';
1137                                 line_len++;
1138                         }
1139
1140                         if (mb_seqlen) {
1141                                 gchar *tmp_jis;
1142
1143                                 tmp_jis = g_new(gchar, tlen + mb_seqlen + 1);
1144                                 conv_euctojis(tmp_jis,
1145                                               tlen + mb_seqlen + 1, tmp);
1146                                 g_snprintf(destp, len - strlen(dest), "%s%s%s",
1147                                            mimehdr_init, mimehdr_charset,
1148                                            mimehdr_enctype);
1149                                 destp += mimehdr_begin_len;
1150                                 line_len += mimehdr_begin_len;
1151
1152                                 to64frombits(destp, tmp_jis, strlen(tmp_jis));
1153                                 line_len += strlen(destp);
1154                                 destp += strlen(destp);
1155
1156                                 strcpy(destp, mimehdr_end);
1157                                 destp += strlen(mimehdr_end);
1158                                 line_len += strlen(mimehdr_end);
1159
1160                                 g_free(tmp_jis);
1161                         } else {
1162                                 strcpy(destp, tmp);
1163                                 line_len += strlen(destp);
1164                                 destp += strlen(destp);
1165                         }
1166
1167                         g_free(tmp);
1168                         /* g_print("line_len = %d\n\n", line_len); */
1169                 } while (*wtmpp != (wchar_t)0);
1170
1171                 while (iswspace(*wsrcp)) {
1172                         gint mbl;
1173
1174                         mbl = wctomb(destp, *wsrcp++);
1175                         if (mbl != -1) {
1176                                 destp += mbl;
1177                                 line_len += mbl;
1178                         }
1179                 }
1180                 *destp = '\0';
1181
1182                 g_free(wtmp);
1183         }
1184
1185         g_free(wsrc);
1186
1187         /* g_print("dest = %s\n", dest); */
1188 }
1189 #endif /* HAVE_LIBJCONV */