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typo fix
[disorder] / lib / mime.c
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460b9539 1/*
2 * This file is part of DisOrder
06819653 3 * Copyright (C) 2005, 2007, 2008 Richard Kettlewell
460b9539 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, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * 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
18 * USA
19 */
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20/** @file lib/mime.c
21 * @brief Support for MIME and allied protocols
22 */
460b9539 23
05b75f8d 24#include "common.h"
460b9539 25
460b9539 26#include <ctype.h>
27
28#include "mem.h"
29#include "mime.h"
30#include "vector.h"
31#include "hex.h"
39d4aa6b 32#include "log.h"
fce810c2 33#include "base64.h"
9bce81d1 34#include "kvp.h"
460b9539 35
39d4aa6b 36/** @brief Match whitespace characters */
460b9539 37static int whitespace(int c) {
38 switch(c) {
39 case ' ':
40 case '\t':
41 case '\r':
42 case '\n':
43 return 1;
44 default:
45 return 0;
46 }
47}
48
39d4aa6b 49/** @brief Match RFC2045 tspecial characters */
a1bedb6d 50int mime_tspecial(int c) {
460b9539 51 switch(c) {
52 case '(':
53 case ')':
54 case '<':
55 case '>':
56 case '@':
57 case ',':
58 case ';':
59 case ':':
60 case '\\':
61 case '"':
62 case '/':
63 case '[':
64 case ']':
65 case '?':
66 case '=':
67 return 1;
68 default:
69 return 0;
70 }
71}
72
82c01b31 73/** @brief Match RFC2616 separator characters */
a1bedb6d 74int mime_http_separator(int c) {
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75 switch(c) {
76 case '(':
77 case ')':
78 case '<':
79 case '>':
80 case '@':
81 case ',':
82 case ';':
83 case ':':
84 case '\\':
85 case '"':
86 case '/':
87 case '[':
88 case ']':
89 case '?':
90 case '=':
91 case '{':
92 case '}':
93 case ' ':
94 case '\t':
95 return 1;
96 default:
97 return 0;
98 }
99}
100
101/** @brief Match CRLF */
102static int iscrlf(const char *ptr) {
103 return ptr[0] == '\r' && ptr[1] == '\n';
104}
105
106/** @brief Skip whitespace
158d0961 107 * @param s Pointer into string
39d4aa6b 108 * @param rfc822_comments If true, skip RFC822 nested comments
158d0961 109 * @return Pointer into string after whitespace
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110 */
111static const char *skipwhite(const char *s, int rfc822_comments) {
460b9539 112 int c, depth;
113
114 for(;;) {
115 switch(c = *s) {
116 case ' ':
117 case '\t':
118 case '\r':
119 case '\n':
120 ++s;
121 break;
122 case '(':
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123 if(!rfc822_comments)
124 return s;
460b9539 125 ++s;
126 depth = 1;
127 while(*s && depth) {
128 c = *s++;
129 switch(c) {
130 case '(': ++depth; break;
131 case ')': --depth; break;
132 case '\\':
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133 if(!*s)
134 return 0;
460b9539 135 ++s;
136 break;
137 }
138 }
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139 if(depth)
140 return 0;
460b9539 141 break;
142 default:
143 return s;
144 }
145 }
146}
147
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148/** @brief Test for a word character
149 * @param c Character to test
a1bedb6d 150 * @param special mime_tspecial() (MIME/RFC2405) or mime_http_separator() (HTTP/RFC2616)
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151 * @return 1 if @p c is a word character, else 0
152 */
153static int iswordchar(int c, int (*special)(int)) {
154 return !(c <= ' ' || c > '~' || special(c));
155}
156
157/** @brief Parse an RFC1521/RFC2616 word
158 * @param s Pointer to start of word
159 * @param valuep Where to store value
a1bedb6d 160 * @param special mime_tspecial() (MIME/RFC2405) or mime_http_separator() (HTTP/RFC2616)
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161 * @return Pointer just after end of word or NULL if there's no word
162 *
163 * A word is a token or a quoted-string.
164 */
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165const char *mime_parse_word(const char *s, char **valuep,
166 int (*special)(int)) {
39d4aa6b 167 struct dynstr value[1];
460b9539 168 int c;
169
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170 dynstr_init(value);
171 if(*s == '"') {
172 ++s;
173 while((c = *s++) != '"') {
174 switch(c) {
175 case '\\':
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176 if(!(c = *s++))
177 return 0;
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178 default:
179 dynstr_append(value, c);
180 break;
181 }
460b9539 182 }
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183 if(!c)
184 return 0;
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185 } else {
186 if(!iswordchar((unsigned char)*s, special))
187 return NULL;
188 dynstr_init(value);
189 while(iswordchar((unsigned char)*s, special))
190 dynstr_append(value, *s++);
460b9539 191 }
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192 dynstr_terminate(value);
193 *valuep = value->vec;
460b9539 194 return s;
195}
196
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197/** @brief Parse an RFC1521/RFC2616 token
198 * @param s Pointer to start of token
199 * @param valuep Where to store value
a1bedb6d 200 * @param special mime_tspecial() (MIME/RFC2405) or mime_http_separator() (HTTP/RFC2616)
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201 * @return Pointer just after end of token or NULL if there's no token
202 */
203static const char *parsetoken(const char *s, char **valuep,
204 int (*special)(int)) {
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205 if(*s == '"')
206 return 0;
a1bedb6d 207 return mime_parse_word(s, valuep, special);
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208}
209
210/** @brief Parse a MIME content-type field
211 * @param s Start of field
212 * @param typep Where to store type
9bce81d1 213 * @param parametersp Where to store parameter list
39d4aa6b 214 * @return 0 on success, non-0 on error
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215 *
216 * See <a href="http://tools.ietf.org/html/rfc2045#section-5">RFC 2045 s5</a>.
39d4aa6b 217 */
460b9539 218int mime_content_type(const char *s,
219 char **typep,
9bce81d1 220 struct kvp **parametersp) {
39d4aa6b 221 struct dynstr type, parametername;
9bce81d1 222 struct kvp *parameters = 0;
223 char *parametervalue;
460b9539 224
225 dynstr_init(&type);
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226 if(!(s = skipwhite(s, 1)))
227 return -1;
228 if(!*s)
229 return -1;
a1bedb6d 230 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 231 dynstr_append(&type, tolower((unsigned char)*s++));
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232 if(!(s = skipwhite(s, 1)))
233 return -1;
234 if(*s++ != '/')
235 return -1;
460b9539 236 dynstr_append(&type, '/');
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237 if(!(s = skipwhite(s, 1)))
238 return -1;
a1bedb6d 239 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 240 dynstr_append(&type, tolower((unsigned char)*s++));
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241 if(!(s = skipwhite(s, 1)))
242 return -1;
460b9539 243
9bce81d1 244 while(*s == ';') {
460b9539 245 dynstr_init(&parametername);
246 ++s;
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247 if(!(s = skipwhite(s, 1)))
248 return -1;
249 if(!*s)
250 return -1;
a1bedb6d 251 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 252 dynstr_append(&parametername, tolower((unsigned char)*s++));
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253 if(!(s = skipwhite(s, 1)))
254 return -1;
255 if(*s++ != '=')
256 return -1;
257 if(!(s = skipwhite(s, 1)))
258 return -1;
a1bedb6d 259 if(!(s = mime_parse_word(s, &parametervalue, mime_tspecial)))
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260 return -1;
261 if(!(s = skipwhite(s, 1)))
262 return -1;
460b9539 263 dynstr_terminate(&parametername);
9bce81d1 264 kvp_set(&parameters, parametername.vec, parametervalue);
265 }
460b9539 266 dynstr_terminate(&type);
267 *typep = type.vec;
9bce81d1 268 *parametersp = parameters;
460b9539 269 return 0;
270}
271
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272/** @brief Parse a MIME message
273 * @param s Start of message
274 * @param callback Called for each header field
275 * @param u Passed to callback
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276 * @return Pointer to decoded body (might be in original string), or NULL on error
277 *
278 * This does an RFC 822-style parse and honors Content-Transfer-Encoding as
279 * described in <a href="http://tools.ietf.org/html/rfc2045#section-6">RFC 2045
280 * s6</a>. @p callback is called for each header field encountered, in order,
281 * with ASCII characters in the header name forced to lower case.
39d4aa6b 282 */
460b9539 283const char *mime_parse(const char *s,
284 int (*callback)(const char *name, const char *value,
285 void *u),
286 void *u) {
287 struct dynstr name, value;
288 char *cte = 0, *p;
289
290 while(*s && !iscrlf(s)) {
291 dynstr_init(&name);
292 dynstr_init(&value);
a1bedb6d 293 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 294 dynstr_append(&name, tolower((unsigned char)*s++));
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295 if(!(s = skipwhite(s, 1)))
296 return 0;
297 if(*s != ':')
298 return 0;
460b9539 299 ++s;
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300 while(*s && !(*s == '\n' && !(s[1] == ' ' || s[1] == '\t'))) {
301 const int c = *s++;
302 /* Strip leading whitespace */
303 if(value.nvec || !(c == ' ' || c == '\t' || c == '\n' || c == '\r'))
304 dynstr_append(&value, c);
305 }
306 /* Strip trailing whitespace */
307 while(value.nvec > 0 && (value.vec[value.nvec - 1] == ' '
308 || value.vec[value.nvec - 1] == '\t'
309 || value.vec[value.nvec - 1] == '\n'
310 || value.vec[value.nvec - 1] == '\r'))
311 --value.nvec;
312 if(*s)
313 ++s;
460b9539 314 dynstr_terminate(&name);
315 dynstr_terminate(&value);
316 if(!strcmp(name.vec, "content-transfer-encoding")) {
317 cte = xstrdup(value.vec);
318 for(p = cte; *p; p++)
319 *p = tolower((unsigned char)*p);
320 }
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321 if(callback(name.vec, value.vec, u))
322 return 0;
460b9539 323 }
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324 if(*s)
325 s += 2;
460b9539 326 if(cte) {
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327 if(!strcmp(cte, "base64"))
328 return mime_base64(s, 0);
329 if(!strcmp(cte, "quoted-printable"))
330 return mime_qp(s);
331 if(!strcmp(cte, "7bit") || !strcmp(cte, "8bit"))
332 return s;
333 error(0, "unknown content-transfer-encoding '%s'", cte);
334 return 0;
460b9539 335 }
336 return s;
337}
338
78d8e29d 339/** @brief Match the boundary string */
460b9539 340static int isboundary(const char *ptr, const char *boundary, size_t bl) {
341 return (ptr[0] == '-'
342 && ptr[1] == '-'
343 && !strncmp(ptr + 2, boundary, bl)
344 && (iscrlf(ptr + bl + 2)
345 || (ptr[bl + 2] == '-'
346 && ptr[bl + 3] == '-'
22896b25 347 && (iscrlf(ptr + bl + 4) || *(ptr + bl + 4) == 0))));
460b9539 348}
349
78d8e29d 350/** @brief Match the final boundary string */
460b9539 351static int isfinal(const char *ptr, const char *boundary, size_t bl) {
352 return (ptr[0] == '-'
353 && ptr[1] == '-'
354 && !strncmp(ptr + 2, boundary, bl)
355 && ptr[bl + 2] == '-'
356 && ptr[bl + 3] == '-'
22896b25 357 && (iscrlf(ptr + bl + 4) || *(ptr + bl + 4) == 0));
460b9539 358}
359
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360/** @brief Parse a multipart MIME body
361 * @param s Start of message
78d8e29d 362 * @param callback Callback for each part
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363 * @param boundary Boundary string
364 * @param u Passed to callback
365 * @return 0 on success, non-0 on error
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366 *
367 * See <a href="http://tools.ietf.org/html/rfc2046#section-5.1">RFC 2046
368 * s5.1</a>. @p callback is called for each part (not yet decoded in any way)
369 * in succession; you should probably call mime_parse() for each part.
39d4aa6b 370 */
460b9539 371int mime_multipart(const char *s,
372 int (*callback)(const char *s, void *u),
373 const char *boundary,
374 void *u) {
375 size_t bl = strlen(boundary);
376 const char *start, *e;
377 int ret;
378
22896b25 379 /* We must start with a boundary string */
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380 if(!isboundary(s, boundary, bl)) {
381 error(0, "mime_multipart: first line is not the boundary string");
22896b25 382 return -1;
d16be832 383 }
22896b25 384 /* Keep going until we hit a final boundary */
460b9539 385 while(!isfinal(s, boundary, bl)) {
386 s = strstr(s, "\r\n") + 2;
387 start = s;
388 while(!isboundary(s, boundary, bl)) {
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389 if(!(e = strstr(s, "\r\n"))) {
390 error(0, "mime_multipart: line does not end CRLF");
22896b25 391 return -1;
d16be832 392 }
460b9539 393 s = e + 2;
394 }
395 if((ret = callback(xstrndup(start,
396 s == start ? 0 : s - start - 2),
397 u)))
398 return ret;
399 }
400 return 0;
401}
402
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403/** @brief Parse an RFC2388-style content-disposition field
404 * @param s Start of field
158d0961 405 * @param dispositionp Where to store disposition
39d4aa6b 406 * @param parameternamep Where to store parameter name
158d0961 407 * @param parametervaluep Wher to store parameter value
39d4aa6b 408 * @return 0 on success, non-0 on error
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409 *
410 * See <a href="http://tools.ietf.org/html/rfc2388#section-3">RFC 2388 s3</a>
411 * and <a href="http://tools.ietf.org/html/rfc2183">RFC 2183</a>.
39d4aa6b 412 */
460b9539 413int mime_rfc2388_content_disposition(const char *s,
414 char **dispositionp,
415 char **parameternamep,
416 char **parametervaluep) {
39d4aa6b 417 struct dynstr disposition, parametername;
460b9539 418
419 dynstr_init(&disposition);
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420 if(!(s = skipwhite(s, 1)))
421 return -1;
422 if(!*s)
423 return -1;
a1bedb6d 424 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 425 dynstr_append(&disposition, tolower((unsigned char)*s++));
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426 if(!(s = skipwhite(s, 1)))
427 return -1;
460b9539 428
429 if(*s == ';') {
430 dynstr_init(&parametername);
431 ++s;
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432 if(!(s = skipwhite(s, 1)))
433 return -1;
434 if(!*s)
435 return -1;
a1bedb6d 436 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 437 dynstr_append(&parametername, tolower((unsigned char)*s++));
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438 if(!(s = skipwhite(s, 1)))
439 return -1;
440 if(*s++ != '=')
441 return -1;
442 if(!(s = skipwhite(s, 1)))
443 return -1;
a1bedb6d 444 if(!(s = mime_parse_word(s, parametervaluep, mime_tspecial)))
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445 return -1;
446 if(!(s = skipwhite(s, 1)))
447 return -1;
460b9539 448 dynstr_terminate(&parametername);
449 *parameternamep = parametername.vec;
450 } else
451 *parametervaluep = *parameternamep = 0;
452 dynstr_terminate(&disposition);
453 *dispositionp = disposition.vec;
454 return 0;
455}
456
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457/** @brief Convert MIME quoted-printable
458 * @param s Quoted-printable data
459 * @return Decoded data
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460 *
461 * See <a href="http://tools.ietf.org/html/rfc2045#section-6.7">RFC 2045
462 * s6.7</a>.
39d4aa6b 463 */
460b9539 464char *mime_qp(const char *s) {
465 struct dynstr d;
466 int c, a, b;
467 const char *t;
468
469 dynstr_init(&d);
470 while((c = *s++)) {
471 switch(c) {
472 case '=':
473 if((a = unhexdigitq(s[0])) != -1
474 && (b = unhexdigitq(s[1])) != -1) {
475 dynstr_append(&d, a * 16 + b);
476 s += 2;
477 } else {
478 t = s;
479 while(*t == ' ' || *t == '\t') ++t;
480 if(iscrlf(t)) {
481 /* soft line break */
482 s = t + 2;
483 } else
484 return 0;
485 }
486 break;
487 case ' ':
488 case '\t':
489 t = s;
490 while(*t == ' ' || *t == '\t') ++t;
491 if(iscrlf(t))
492 /* trailing space is always eliminated */
493 s = t;
494 else
495 dynstr_append(&d, c);
496 break;
497 default:
498 dynstr_append(&d, c);
499 break;
500 }
501 }
502 dynstr_terminate(&d);
503 return d.vec;
504}
505
06819653 506/** @brief Match cookie separator characters
507 *
508 * This is a subset of the RFC2616 specials, and technically is in breach of
509 * the specification. However rejecting (in particular) slashes is
510 * unreasonably strict and has broken at least one (admittedly somewhat
511 * obscure) browser, so we're more forgiving.
512 */
513static int cookie_separator(int c) {
514 switch(c) {
515 case '(':
516 case ')':
517 case ',':
518 case ';':
519 case '=':
520 case ' ':
521 case '"':
522 case '\t':
523 return 1;
524
525 default:
526 return 0;
527 }
528}
529
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530/** @brief Match cookie value separator characters
531 *
532 * Same as cookie_separator() but allows for @c = in cookie values.
533 */
534static int cookie_value_separator(int c) {
535 switch(c) {
536 case '(':
537 case ')':
538 case ',':
539 case ';':
540 case ' ':
541 case '"':
542 case '\t':
543 return 1;
544
545 default:
546 return 0;
547 }
548}
549
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550/** @brief Parse a RFC2109 Cookie: header
551 * @param s Header field value
552 * @param cd Where to store result
553 * @return 0 on success, non-0 on error
36bde473 554 *
555 * See <a href="http://tools.ietf.org/html/rfc2109">RFC 2109</a>.
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556 */
557int parse_cookie(const char *s,
558 struct cookiedata *cd) {
559 char *n = 0, *v = 0;
560
561 memset(cd, 0, sizeof *cd);
562 s = skipwhite(s, 0);
563 while(*s) {
564 /* Skip separators */
565 if(*s == ';' || *s == ',') {
566 ++s;
567 s = skipwhite(s, 0);
568 continue;
569 }
06819653 570 if(!(s = parsetoken(s, &n, cookie_separator))) {
571 error(0, "parse_cookie: cannot parse attribute name");
121f51ac 572 return -1;
06819653 573 }
39d4aa6b 574 s = skipwhite(s, 0);
06819653 575 if(*s++ != '=') {
576 error(0, "parse_cookie: did not find expected '='");
121f51ac 577 return -1;
06819653 578 }
39d4aa6b 579 s = skipwhite(s, 0);
e9eb8f7b 580 if(!(s = mime_parse_word(s, &v, cookie_value_separator))) {
06819653 581 error(0, "parse_cookie: cannot parse value for '%s'", n);
121f51ac 582 return -1;
06819653 583 }
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584 if(n[0] == '$') {
585 /* Some bit of meta-information */
586 if(!strcmp(n, "$Version"))
587 cd->version = v;
588 else if(!strcmp(n, "$Path")) {
589 if(cd->ncookies > 0 && cd->cookies[cd->ncookies-1].path == 0)
590 cd->cookies[cd->ncookies-1].path = v;
591 else {
592 error(0, "redundant $Path in Cookie: header");
593 return -1;
594 }
595 } else if(!strcmp(n, "$Domain")) {
596 if(cd->ncookies > 0 && cd->cookies[cd->ncookies-1].domain == 0)
597 cd->cookies[cd->ncookies-1].domain = v;
598 else {
599 error(0, "redundant $Domain in Cookie: header");
600 return -1;
601 }
602 }
603 } else {
604 /* It's a new cookie */
605 cd->cookies = xrealloc(cd->cookies,
606 (cd->ncookies + 1) * sizeof (struct cookie));
607 cd->cookies[cd->ncookies].name = n;
608 cd->cookies[cd->ncookies].value = v;
609 cd->cookies[cd->ncookies].path = 0;
610 cd->cookies[cd->ncookies].domain = 0;
611 ++cd->ncookies;
612 }
613 s = skipwhite(s, 0);
614 if(*s && (*s != ',' && *s != ';')) {
615 error(0, "missing separator in Cookie: header");
616 return -1;
617 }
618 }
619 return 0;
620}
621
622/** @brief Find a named cookie
623 * @param cd Parse cookie data
624 * @param name Name of cookie
625 * @return Cookie structure or NULL if not found
626 */
627const struct cookie *find_cookie(const struct cookiedata *cd,
628 const char *name) {
629 int n;
630
631 for(n = 0; n < cd->ncookies; ++n)
632 if(!strcmp(cd->cookies[n].name, name))
633 return &cd->cookies[n];
634 return 0;
635}
636
36bde473 637/** @brief RFC822 quoting
638 * @param s String to quote
639 * @param force If non-0, always quote
640 * @return Possibly quoted string
641 */
642char *quote822(const char *s, int force) {
643 const char *t;
644 struct dynstr d[1];
645 int c;
646
647 if(!force) {
648 /* See if we need to quote */
649 for(t = s; (c = (unsigned char)*t); ++t) {
a1bedb6d 650 if(mime_tspecial(c) || mime_http_separator(c) || whitespace(c))
36bde473 651 break;
652 }
653 if(*t)
654 force = 1;
655 }
656
657 if(!force)
658 return xstrdup(s);
659
660 dynstr_init(d);
661 dynstr_append(d, '"');
662 for(t = s; (c = (unsigned char)*t); ++t) {
663 if(c == '"' || c == '\\')
664 dynstr_append(d, '\\');
665 dynstr_append(d, c);
666 }
667 dynstr_append(d, '"');
668 dynstr_terminate(d);
669 return d->vec;
670}
671
bb6ae3fb 672/** @brief Return true if @p ptr points at trailing space */
673static int is_trailing_space(const char *ptr) {
674 if(*ptr == ' ' || *ptr == '\t') {
675 while(*ptr == ' ' || *ptr == '\t')
676 ++ptr;
677 return *ptr == '\n' || *ptr == 0;
678 } else
679 return 0;
680}
681
682/** @brief Encoding text as quoted-printable
683 * @param text String to encode
684 * @return Encoded string
685 *
686 * See <a href="http://tools.ietf.org/html/rfc2045#section-6.7">RFC2045
687 * s6.7</a>.
688 */
689char *mime_to_qp(const char *text) {
690 struct dynstr d[1];
691 int linelength = 0; /* length of current line */
692 char buffer[10];
693
694 dynstr_init(d);
695 /* The rules are:
696 * 1. Anything except newline can be replaced with =%02X
697 * 2. Newline, 33-60 and 62-126 stand for themselves (i.e. not '=')
698 * 3. Non-trailing space/tab stand for themselves.
699 * 4. Output lines are limited to 76 chars, with =<newline> being used
700 * as a soft line break
701 * 5. Newlines aren't counted towards the 76 char limit.
702 */
703 while(*text) {
704 const int c = (unsigned char)*text;
705 if(c == '\n') {
706 /* Newline stands as itself */
707 dynstr_append(d, '\n');
708 linelength = 0;
709 } else if((c >= 33 && c <= 126 && c != '=')
710 || ((c == ' ' || c == '\t')
711 && !is_trailing_space(text))) {
712 /* Things that can stand for themselves */
713 dynstr_append(d, c);
714 ++linelength;
715 } else {
716 /* Anything else that needs encoding */
717 snprintf(buffer, sizeof buffer, "=%02X", c);
718 dynstr_append_string(d, buffer);
719 linelength += 3;
720 }
721 ++text;
722 if(linelength > 73 && *text && *text != '\n') {
723 /* Next character might overflow 76 character limit if encoded, so we
724 * insert a soft break */
725 dynstr_append_string(d, "=\n");
726 linelength = 0;
727 }
728 }
729 /* Ensure there is a final newline */
730 if(linelength)
731 dynstr_append(d, '\n');
732 /* That's all */
733 dynstr_terminate(d);
734 return d->vec;
735}
736
737/** @brief Encode text
738 * @param text Underlying UTF-8 text
739 * @param charsetp Where to store charset string
740 * @param encodingp Where to store encoding string
0590cedc 741 * @return Encoded text (might be @p text)
bb6ae3fb 742 */
743const char *mime_encode_text(const char *text,
744 const char **charsetp,
745 const char **encodingp) {
746 const char *ptr;
747
748 /* See if there are in fact any non-ASCII characters */
749 for(ptr = text; *ptr; ++ptr)
750 if((unsigned char)*ptr >= 128)
751 break;
752 if(!*ptr) {
753 /* Plain old ASCII, no encoding required */
754 *charsetp = "us-ascii";
755 *encodingp = "7bit";
756 return text;
757 }
758 *charsetp = "utf-8";
759 *encodingp = "quoted-printable";
760 return mime_to_qp(text);
761}
762
460b9539 763/*
764Local Variables:
765c-basic-offset:2
766comment-column:40
767fill-column:79
768End:
769*/