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Merge from disorder.dev.
[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 *
e7eb3a27 5 * This program is free software: you can redistribute it and/or modify
460b9539 6 * it under the terms of the GNU General Public License as published by
e7eb3a27 7 * the Free Software Foundation, either version 3 of the License, or
460b9539 8 * (at your option) any later version.
e7eb3a27
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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 *
460b9539 15 * You should have received a copy of the GNU General Public License
e7eb3a27 16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
460b9539 17 */
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18/** @file lib/mime.c
19 * @brief Support for MIME and allied protocols
20 */
460b9539 21
05b75f8d 22#include "common.h"
460b9539 23
460b9539 24#include <ctype.h>
25
26#include "mem.h"
27#include "mime.h"
28#include "vector.h"
29#include "hex.h"
39d4aa6b 30#include "log.h"
fce810c2 31#include "base64.h"
9bce81d1 32#include "kvp.h"
460b9539 33
39d4aa6b 34/** @brief Match whitespace characters */
460b9539 35static int whitespace(int c) {
36 switch(c) {
37 case ' ':
38 case '\t':
39 case '\r':
40 case '\n':
41 return 1;
42 default:
43 return 0;
44 }
45}
46
39d4aa6b 47/** @brief Match RFC2045 tspecial characters */
a1bedb6d 48int mime_tspecial(int c) {
460b9539 49 switch(c) {
50 case '(':
51 case ')':
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 return 1;
66 default:
67 return 0;
68 }
69}
70
82c01b31 71/** @brief Match RFC2616 separator characters */
a1bedb6d 72int mime_http_separator(int c) {
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73 switch(c) {
74 case '(':
75 case ')':
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 '\t':
93 return 1;
94 default:
95 return 0;
96 }
97}
98
99/** @brief Match CRLF */
100static int iscrlf(const char *ptr) {
101 return ptr[0] == '\r' && ptr[1] == '\n';
102}
103
104/** @brief Skip whitespace
158d0961 105 * @param s Pointer into string
39d4aa6b 106 * @param rfc822_comments If true, skip RFC822 nested comments
158d0961 107 * @return Pointer into string after whitespace
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108 */
109static const char *skipwhite(const char *s, int rfc822_comments) {
460b9539 110 int c, depth;
111
112 for(;;) {
113 switch(c = *s) {
114 case ' ':
115 case '\t':
116 case '\r':
117 case '\n':
118 ++s;
119 break;
120 case '(':
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121 if(!rfc822_comments)
122 return s;
460b9539 123 ++s;
124 depth = 1;
125 while(*s && depth) {
126 c = *s++;
127 switch(c) {
128 case '(': ++depth; break;
129 case ')': --depth; break;
130 case '\\':
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131 if(!*s)
132 return 0;
460b9539 133 ++s;
134 break;
135 }
136 }
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137 if(depth)
138 return 0;
460b9539 139 break;
140 default:
141 return s;
142 }
143 }
144}
145
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146/** @brief Test for a word character
147 * @param c Character to test
a1bedb6d 148 * @param special mime_tspecial() (MIME/RFC2405) or mime_http_separator() (HTTP/RFC2616)
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149 * @return 1 if @p c is a word character, else 0
150 */
151static int iswordchar(int c, int (*special)(int)) {
152 return !(c <= ' ' || c > '~' || special(c));
153}
154
155/** @brief Parse an RFC1521/RFC2616 word
156 * @param s Pointer to start of word
157 * @param valuep Where to store value
a1bedb6d 158 * @param special mime_tspecial() (MIME/RFC2405) or mime_http_separator() (HTTP/RFC2616)
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159 * @return Pointer just after end of word or NULL if there's no word
160 *
161 * A word is a token or a quoted-string.
162 */
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163const char *mime_parse_word(const char *s, char **valuep,
164 int (*special)(int)) {
39d4aa6b 165 struct dynstr value[1];
460b9539 166 int c;
167
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168 dynstr_init(value);
169 if(*s == '"') {
170 ++s;
171 while((c = *s++) != '"') {
172 switch(c) {
173 case '\\':
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174 if(!(c = *s++))
175 return 0;
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176 default:
177 dynstr_append(value, c);
178 break;
179 }
460b9539 180 }
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181 if(!c)
182 return 0;
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183 } else {
184 if(!iswordchar((unsigned char)*s, special))
185 return NULL;
186 dynstr_init(value);
187 while(iswordchar((unsigned char)*s, special))
188 dynstr_append(value, *s++);
460b9539 189 }
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190 dynstr_terminate(value);
191 *valuep = value->vec;
460b9539 192 return s;
193}
194
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195/** @brief Parse an RFC1521/RFC2616 token
196 * @param s Pointer to start of token
197 * @param valuep Where to store value
a1bedb6d 198 * @param special mime_tspecial() (MIME/RFC2405) or mime_http_separator() (HTTP/RFC2616)
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199 * @return Pointer just after end of token or NULL if there's no token
200 */
201static const char *parsetoken(const char *s, char **valuep,
202 int (*special)(int)) {
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203 if(*s == '"')
204 return 0;
a1bedb6d 205 return mime_parse_word(s, valuep, special);
39d4aa6b
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206}
207
208/** @brief Parse a MIME content-type field
209 * @param s Start of field
210 * @param typep Where to store type
9bce81d1 211 * @param parametersp Where to store parameter list
39d4aa6b 212 * @return 0 on success, non-0 on error
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213 *
214 * See <a href="http://tools.ietf.org/html/rfc2045#section-5">RFC 2045 s5</a>.
39d4aa6b 215 */
460b9539 216int mime_content_type(const char *s,
217 char **typep,
9bce81d1 218 struct kvp **parametersp) {
39d4aa6b 219 struct dynstr type, parametername;
9bce81d1 220 struct kvp *parameters = 0;
221 char *parametervalue;
460b9539 222
223 dynstr_init(&type);
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224 if(!(s = skipwhite(s, 1)))
225 return -1;
226 if(!*s)
227 return -1;
a1bedb6d 228 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 229 dynstr_append(&type, tolower((unsigned char)*s++));
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230 if(!(s = skipwhite(s, 1)))
231 return -1;
232 if(*s++ != '/')
233 return -1;
460b9539 234 dynstr_append(&type, '/');
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235 if(!(s = skipwhite(s, 1)))
236 return -1;
a1bedb6d 237 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 238 dynstr_append(&type, tolower((unsigned char)*s++));
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239 if(!(s = skipwhite(s, 1)))
240 return -1;
460b9539 241
9bce81d1 242 while(*s == ';') {
460b9539 243 dynstr_init(&parametername);
244 ++s;
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245 if(!(s = skipwhite(s, 1)))
246 return -1;
247 if(!*s)
248 return -1;
a1bedb6d 249 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 250 dynstr_append(&parametername, tolower((unsigned char)*s++));
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251 if(!(s = skipwhite(s, 1)))
252 return -1;
253 if(*s++ != '=')
254 return -1;
255 if(!(s = skipwhite(s, 1)))
256 return -1;
a1bedb6d 257 if(!(s = mime_parse_word(s, &parametervalue, mime_tspecial)))
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258 return -1;
259 if(!(s = skipwhite(s, 1)))
260 return -1;
460b9539 261 dynstr_terminate(&parametername);
9bce81d1 262 kvp_set(&parameters, parametername.vec, parametervalue);
263 }
460b9539 264 dynstr_terminate(&type);
265 *typep = type.vec;
9bce81d1 266 *parametersp = parameters;
460b9539 267 return 0;
268}
269
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270/** @brief Parse a MIME message
271 * @param s Start of message
272 * @param callback Called for each header field
273 * @param u Passed to callback
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274 * @return Pointer to decoded body (might be in original string), or NULL on error
275 *
276 * This does an RFC 822-style parse and honors Content-Transfer-Encoding as
277 * described in <a href="http://tools.ietf.org/html/rfc2045#section-6">RFC 2045
278 * s6</a>. @p callback is called for each header field encountered, in order,
279 * with ASCII characters in the header name forced to lower case.
39d4aa6b 280 */
460b9539 281const char *mime_parse(const char *s,
282 int (*callback)(const char *name, const char *value,
283 void *u),
284 void *u) {
285 struct dynstr name, value;
286 char *cte = 0, *p;
287
288 while(*s && !iscrlf(s)) {
289 dynstr_init(&name);
290 dynstr_init(&value);
a1bedb6d 291 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 292 dynstr_append(&name, tolower((unsigned char)*s++));
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293 if(!(s = skipwhite(s, 1)))
294 return 0;
295 if(*s != ':')
296 return 0;
460b9539 297 ++s;
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298 while(*s && !(*s == '\n' && !(s[1] == ' ' || s[1] == '\t'))) {
299 const int c = *s++;
300 /* Strip leading whitespace */
301 if(value.nvec || !(c == ' ' || c == '\t' || c == '\n' || c == '\r'))
302 dynstr_append(&value, c);
303 }
304 /* Strip trailing whitespace */
305 while(value.nvec > 0 && (value.vec[value.nvec - 1] == ' '
306 || value.vec[value.nvec - 1] == '\t'
307 || value.vec[value.nvec - 1] == '\n'
308 || value.vec[value.nvec - 1] == '\r'))
309 --value.nvec;
310 if(*s)
311 ++s;
460b9539 312 dynstr_terminate(&name);
313 dynstr_terminate(&value);
314 if(!strcmp(name.vec, "content-transfer-encoding")) {
315 cte = xstrdup(value.vec);
316 for(p = cte; *p; p++)
317 *p = tolower((unsigned char)*p);
318 }
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319 if(callback(name.vec, value.vec, u))
320 return 0;
460b9539 321 }
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322 if(*s)
323 s += 2;
460b9539 324 if(cte) {
121f51ac
RK
325 if(!strcmp(cte, "base64"))
326 return mime_base64(s, 0);
327 if(!strcmp(cte, "quoted-printable"))
328 return mime_qp(s);
329 if(!strcmp(cte, "7bit") || !strcmp(cte, "8bit"))
330 return s;
331 error(0, "unknown content-transfer-encoding '%s'", cte);
332 return 0;
460b9539 333 }
334 return s;
335}
336
78d8e29d 337/** @brief Match the boundary string */
460b9539 338static int isboundary(const char *ptr, const char *boundary, size_t bl) {
339 return (ptr[0] == '-'
340 && ptr[1] == '-'
341 && !strncmp(ptr + 2, boundary, bl)
342 && (iscrlf(ptr + bl + 2)
343 || (ptr[bl + 2] == '-'
344 && ptr[bl + 3] == '-'
22896b25 345 && (iscrlf(ptr + bl + 4) || *(ptr + bl + 4) == 0))));
460b9539 346}
347
78d8e29d 348/** @brief Match the final boundary string */
460b9539 349static int isfinal(const char *ptr, const char *boundary, size_t bl) {
350 return (ptr[0] == '-'
351 && ptr[1] == '-'
352 && !strncmp(ptr + 2, boundary, bl)
353 && ptr[bl + 2] == '-'
354 && ptr[bl + 3] == '-'
22896b25 355 && (iscrlf(ptr + bl + 4) || *(ptr + bl + 4) == 0));
460b9539 356}
357
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358/** @brief Parse a multipart MIME body
359 * @param s Start of message
78d8e29d 360 * @param callback Callback for each part
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361 * @param boundary Boundary string
362 * @param u Passed to callback
363 * @return 0 on success, non-0 on error
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364 *
365 * See <a href="http://tools.ietf.org/html/rfc2046#section-5.1">RFC 2046
366 * s5.1</a>. @p callback is called for each part (not yet decoded in any way)
367 * in succession; you should probably call mime_parse() for each part.
39d4aa6b 368 */
460b9539 369int mime_multipart(const char *s,
370 int (*callback)(const char *s, void *u),
371 const char *boundary,
372 void *u) {
373 size_t bl = strlen(boundary);
374 const char *start, *e;
375 int ret;
376
22896b25 377 /* We must start with a boundary string */
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378 if(!isboundary(s, boundary, bl)) {
379 error(0, "mime_multipart: first line is not the boundary string");
22896b25 380 return -1;
d16be832 381 }
22896b25 382 /* Keep going until we hit a final boundary */
460b9539 383 while(!isfinal(s, boundary, bl)) {
384 s = strstr(s, "\r\n") + 2;
385 start = s;
386 while(!isboundary(s, boundary, bl)) {
d16be832
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387 if(!(e = strstr(s, "\r\n"))) {
388 error(0, "mime_multipart: line does not end CRLF");
22896b25 389 return -1;
d16be832 390 }
460b9539 391 s = e + 2;
392 }
393 if((ret = callback(xstrndup(start,
394 s == start ? 0 : s - start - 2),
395 u)))
396 return ret;
397 }
398 return 0;
399}
400
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401/** @brief Parse an RFC2388-style content-disposition field
402 * @param s Start of field
158d0961 403 * @param dispositionp Where to store disposition
39d4aa6b 404 * @param parameternamep Where to store parameter name
158d0961 405 * @param parametervaluep Wher to store parameter value
39d4aa6b 406 * @return 0 on success, non-0 on error
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407 *
408 * See <a href="http://tools.ietf.org/html/rfc2388#section-3">RFC 2388 s3</a>
409 * and <a href="http://tools.ietf.org/html/rfc2183">RFC 2183</a>.
39d4aa6b 410 */
460b9539 411int mime_rfc2388_content_disposition(const char *s,
412 char **dispositionp,
413 char **parameternamep,
414 char **parametervaluep) {
39d4aa6b 415 struct dynstr disposition, parametername;
460b9539 416
417 dynstr_init(&disposition);
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418 if(!(s = skipwhite(s, 1)))
419 return -1;
420 if(!*s)
421 return -1;
a1bedb6d 422 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 423 dynstr_append(&disposition, tolower((unsigned char)*s++));
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424 if(!(s = skipwhite(s, 1)))
425 return -1;
460b9539 426
427 if(*s == ';') {
428 dynstr_init(&parametername);
429 ++s;
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430 if(!(s = skipwhite(s, 1)))
431 return -1;
432 if(!*s)
433 return -1;
a1bedb6d 434 while(*s && !mime_tspecial(*s) && !whitespace(*s))
460b9539 435 dynstr_append(&parametername, tolower((unsigned char)*s++));
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436 if(!(s = skipwhite(s, 1)))
437 return -1;
438 if(*s++ != '=')
439 return -1;
440 if(!(s = skipwhite(s, 1)))
441 return -1;
a1bedb6d 442 if(!(s = mime_parse_word(s, parametervaluep, mime_tspecial)))
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443 return -1;
444 if(!(s = skipwhite(s, 1)))
445 return -1;
460b9539 446 dynstr_terminate(&parametername);
447 *parameternamep = parametername.vec;
448 } else
449 *parametervaluep = *parameternamep = 0;
450 dynstr_terminate(&disposition);
451 *dispositionp = disposition.vec;
452 return 0;
453}
454
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455/** @brief Convert MIME quoted-printable
456 * @param s Quoted-printable data
457 * @return Decoded data
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458 *
459 * See <a href="http://tools.ietf.org/html/rfc2045#section-6.7">RFC 2045
460 * s6.7</a>.
39d4aa6b 461 */
460b9539 462char *mime_qp(const char *s) {
463 struct dynstr d;
464 int c, a, b;
465 const char *t;
466
467 dynstr_init(&d);
468 while((c = *s++)) {
469 switch(c) {
470 case '=':
471 if((a = unhexdigitq(s[0])) != -1
472 && (b = unhexdigitq(s[1])) != -1) {
473 dynstr_append(&d, a * 16 + b);
474 s += 2;
475 } else {
476 t = s;
477 while(*t == ' ' || *t == '\t') ++t;
478 if(iscrlf(t)) {
479 /* soft line break */
480 s = t + 2;
481 } else
482 return 0;
483 }
484 break;
485 case ' ':
486 case '\t':
487 t = s;
488 while(*t == ' ' || *t == '\t') ++t;
489 if(iscrlf(t))
490 /* trailing space is always eliminated */
491 s = t;
492 else
493 dynstr_append(&d, c);
494 break;
495 default:
496 dynstr_append(&d, c);
497 break;
498 }
499 }
500 dynstr_terminate(&d);
501 return d.vec;
502}
503
06819653 504/** @brief Match cookie separator characters
505 *
506 * This is a subset of the RFC2616 specials, and technically is in breach of
507 * the specification. However rejecting (in particular) slashes is
508 * unreasonably strict and has broken at least one (admittedly somewhat
509 * obscure) browser, so we're more forgiving.
510 */
511static int cookie_separator(int c) {
512 switch(c) {
513 case '(':
514 case ')':
515 case ',':
516 case ';':
517 case '=':
518 case ' ':
519 case '"':
520 case '\t':
521 return 1;
522
523 default:
524 return 0;
525 }
526}
527
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528/** @brief Match cookie value separator characters
529 *
530 * Same as cookie_separator() but allows for @c = in cookie values.
531 */
532static int cookie_value_separator(int c) {
533 switch(c) {
534 case '(':
535 case ')':
536 case ',':
537 case ';':
538 case ' ':
539 case '"':
540 case '\t':
541 return 1;
542
543 default:
544 return 0;
545 }
546}
547
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548/** @brief Parse a RFC2109 Cookie: header
549 * @param s Header field value
550 * @param cd Where to store result
551 * @return 0 on success, non-0 on error
36bde473 552 *
553 * See <a href="http://tools.ietf.org/html/rfc2109">RFC 2109</a>.
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554 */
555int parse_cookie(const char *s,
556 struct cookiedata *cd) {
557 char *n = 0, *v = 0;
558
559 memset(cd, 0, sizeof *cd);
560 s = skipwhite(s, 0);
561 while(*s) {
562 /* Skip separators */
563 if(*s == ';' || *s == ',') {
564 ++s;
565 s = skipwhite(s, 0);
566 continue;
567 }
06819653 568 if(!(s = parsetoken(s, &n, cookie_separator))) {
569 error(0, "parse_cookie: cannot parse attribute name");
121f51ac 570 return -1;
06819653 571 }
39d4aa6b 572 s = skipwhite(s, 0);
06819653 573 if(*s++ != '=') {
574 error(0, "parse_cookie: did not find expected '='");
121f51ac 575 return -1;
06819653 576 }
39d4aa6b 577 s = skipwhite(s, 0);
e9eb8f7b 578 if(!(s = mime_parse_word(s, &v, cookie_value_separator))) {
06819653 579 error(0, "parse_cookie: cannot parse value for '%s'", n);
121f51ac 580 return -1;
06819653 581 }
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582 if(n[0] == '$') {
583 /* Some bit of meta-information */
584 if(!strcmp(n, "$Version"))
585 cd->version = v;
586 else if(!strcmp(n, "$Path")) {
587 if(cd->ncookies > 0 && cd->cookies[cd->ncookies-1].path == 0)
588 cd->cookies[cd->ncookies-1].path = v;
589 else {
590 error(0, "redundant $Path in Cookie: header");
591 return -1;
592 }
593 } else if(!strcmp(n, "$Domain")) {
594 if(cd->ncookies > 0 && cd->cookies[cd->ncookies-1].domain == 0)
595 cd->cookies[cd->ncookies-1].domain = v;
596 else {
597 error(0, "redundant $Domain in Cookie: header");
598 return -1;
599 }
600 }
601 } else {
602 /* It's a new cookie */
603 cd->cookies = xrealloc(cd->cookies,
604 (cd->ncookies + 1) * sizeof (struct cookie));
605 cd->cookies[cd->ncookies].name = n;
606 cd->cookies[cd->ncookies].value = v;
607 cd->cookies[cd->ncookies].path = 0;
608 cd->cookies[cd->ncookies].domain = 0;
609 ++cd->ncookies;
610 }
611 s = skipwhite(s, 0);
612 if(*s && (*s != ',' && *s != ';')) {
613 error(0, "missing separator in Cookie: header");
614 return -1;
615 }
616 }
617 return 0;
618}
619
620/** @brief Find a named cookie
621 * @param cd Parse cookie data
622 * @param name Name of cookie
623 * @return Cookie structure or NULL if not found
624 */
625const struct cookie *find_cookie(const struct cookiedata *cd,
626 const char *name) {
627 int n;
628
629 for(n = 0; n < cd->ncookies; ++n)
630 if(!strcmp(cd->cookies[n].name, name))
631 return &cd->cookies[n];
632 return 0;
633}
634
36bde473 635/** @brief RFC822 quoting
636 * @param s String to quote
637 * @param force If non-0, always quote
638 * @return Possibly quoted string
639 */
640char *quote822(const char *s, int force) {
641 const char *t;
642 struct dynstr d[1];
643 int c;
644
645 if(!force) {
646 /* See if we need to quote */
647 for(t = s; (c = (unsigned char)*t); ++t) {
a1bedb6d 648 if(mime_tspecial(c) || mime_http_separator(c) || whitespace(c))
36bde473 649 break;
650 }
651 if(*t)
652 force = 1;
653 }
654
655 if(!force)
656 return xstrdup(s);
657
658 dynstr_init(d);
659 dynstr_append(d, '"');
660 for(t = s; (c = (unsigned char)*t); ++t) {
661 if(c == '"' || c == '\\')
662 dynstr_append(d, '\\');
663 dynstr_append(d, c);
664 }
665 dynstr_append(d, '"');
666 dynstr_terminate(d);
667 return d->vec;
668}
669
bb6ae3fb 670/** @brief Return true if @p ptr points at trailing space */
671static int is_trailing_space(const char *ptr) {
672 if(*ptr == ' ' || *ptr == '\t') {
673 while(*ptr == ' ' || *ptr == '\t')
674 ++ptr;
675 return *ptr == '\n' || *ptr == 0;
676 } else
677 return 0;
678}
679
680/** @brief Encoding text as quoted-printable
681 * @param text String to encode
682 * @return Encoded string
683 *
684 * See <a href="http://tools.ietf.org/html/rfc2045#section-6.7">RFC2045
685 * s6.7</a>.
686 */
687char *mime_to_qp(const char *text) {
688 struct dynstr d[1];
689 int linelength = 0; /* length of current line */
690 char buffer[10];
691
692 dynstr_init(d);
693 /* The rules are:
694 * 1. Anything except newline can be replaced with =%02X
695 * 2. Newline, 33-60 and 62-126 stand for themselves (i.e. not '=')
696 * 3. Non-trailing space/tab stand for themselves.
697 * 4. Output lines are limited to 76 chars, with =<newline> being used
698 * as a soft line break
699 * 5. Newlines aren't counted towards the 76 char limit.
700 */
701 while(*text) {
702 const int c = (unsigned char)*text;
703 if(c == '\n') {
704 /* Newline stands as itself */
705 dynstr_append(d, '\n');
706 linelength = 0;
707 } else if((c >= 33 && c <= 126 && c != '=')
708 || ((c == ' ' || c == '\t')
709 && !is_trailing_space(text))) {
710 /* Things that can stand for themselves */
711 dynstr_append(d, c);
712 ++linelength;
713 } else {
714 /* Anything else that needs encoding */
715 snprintf(buffer, sizeof buffer, "=%02X", c);
716 dynstr_append_string(d, buffer);
717 linelength += 3;
718 }
719 ++text;
720 if(linelength > 73 && *text && *text != '\n') {
721 /* Next character might overflow 76 character limit if encoded, so we
722 * insert a soft break */
723 dynstr_append_string(d, "=\n");
724 linelength = 0;
725 }
726 }
727 /* Ensure there is a final newline */
728 if(linelength)
729 dynstr_append(d, '\n');
730 /* That's all */
731 dynstr_terminate(d);
732 return d->vec;
733}
734
735/** @brief Encode text
736 * @param text Underlying UTF-8 text
737 * @param charsetp Where to store charset string
738 * @param encodingp Where to store encoding string
0590cedc 739 * @return Encoded text (might be @p text)
bb6ae3fb 740 */
741const char *mime_encode_text(const char *text,
742 const char **charsetp,
743 const char **encodingp) {
744 const char *ptr;
745
746 /* See if there are in fact any non-ASCII characters */
747 for(ptr = text; *ptr; ++ptr)
748 if((unsigned char)*ptr >= 128)
749 break;
750 if(!*ptr) {
751 /* Plain old ASCII, no encoding required */
752 *charsetp = "us-ascii";
753 *encodingp = "7bit";
754 return text;
755 }
756 *charsetp = "utf-8";
757 *encodingp = "quoted-printable";
758 return mime_to_qp(text);
759}
760
460b9539 761/*
762Local Variables:
763c-basic-offset:2
764comment-column:40
765fill-column:79
766End:
767*/