Merge branch 'cp/completion-clone-recurse-submodules' into maint
[git] / mailinfo.c
1 #include "cache.h"
2 #include "utf8.h"
3 #include "strbuf.h"
4 #include "mailinfo.h"
5
6 static void cleanup_space(struct strbuf *sb)
7 {
8         size_t pos, cnt;
9         for (pos = 0; pos < sb->len; pos++) {
10                 if (isspace(sb->buf[pos])) {
11                         sb->buf[pos] = ' ';
12                         for (cnt = 0; isspace(sb->buf[pos + cnt + 1]); cnt++);
13                         strbuf_remove(sb, pos + 1, cnt);
14                 }
15         }
16 }
17
18 static void get_sane_name(struct strbuf *out, struct strbuf *name, struct strbuf *email)
19 {
20         struct strbuf *src = name;
21         if (name->len < 3 || 60 < name->len || strchr(name->buf, '@') ||
22                 strchr(name->buf, '<') || strchr(name->buf, '>'))
23                 src = email;
24         else if (name == out)
25                 return;
26         strbuf_reset(out);
27         strbuf_addbuf(out, src);
28 }
29
30 static void parse_bogus_from(struct mailinfo *mi, const struct strbuf *line)
31 {
32         /* John Doe <johndoe> */
33
34         char *bra, *ket;
35         /* This is fallback, so do not bother if we already have an
36          * e-mail address.
37          */
38         if (mi->email.len)
39                 return;
40
41         bra = strchr(line->buf, '<');
42         if (!bra)
43                 return;
44         ket = strchr(bra, '>');
45         if (!ket)
46                 return;
47
48         strbuf_reset(&mi->email);
49         strbuf_add(&mi->email, bra + 1, ket - bra - 1);
50
51         strbuf_reset(&mi->name);
52         strbuf_add(&mi->name, line->buf, bra - line->buf);
53         strbuf_trim(&mi->name);
54         get_sane_name(&mi->name, &mi->name, &mi->email);
55 }
56
57 static void handle_from(struct mailinfo *mi, const struct strbuf *from)
58 {
59         char *at;
60         size_t el;
61         struct strbuf f;
62
63         strbuf_init(&f, from->len);
64         strbuf_addbuf(&f, from);
65
66         at = strchr(f.buf, '@');
67         if (!at) {
68                 parse_bogus_from(mi, from);
69                 return;
70         }
71
72         /*
73          * If we already have one email, don't take any confusing lines
74          */
75         if (mi->email.len && strchr(at + 1, '@')) {
76                 strbuf_release(&f);
77                 return;
78         }
79
80         /* Pick up the string around '@', possibly delimited with <>
81          * pair; that is the email part.
82          */
83         while (at > f.buf) {
84                 char c = at[-1];
85                 if (isspace(c))
86                         break;
87                 if (c == '<') {
88                         at[-1] = ' ';
89                         break;
90                 }
91                 at--;
92         }
93         el = strcspn(at, " \n\t\r\v\f>");
94         strbuf_reset(&mi->email);
95         strbuf_add(&mi->email, at, el);
96         strbuf_remove(&f, at - f.buf, el + (at[el] ? 1 : 0));
97
98         /* The remainder is name.  It could be
99          *
100          * - "John Doe <john.doe@xz>"                   (a), or
101          * - "john.doe@xz (John Doe)"                   (b), or
102          * - "John (zzz) Doe <john.doe@xz> (Comment)"   (c)
103          *
104          * but we have removed the email part, so
105          *
106          * - remove extra spaces which could stay after email (case 'c'), and
107          * - trim from both ends, possibly removing the () pair at the end
108          *   (cases 'a' and 'b').
109          */
110         cleanup_space(&f);
111         strbuf_trim(&f);
112         if (f.buf[0] == '(' && f.len && f.buf[f.len - 1] == ')') {
113                 strbuf_remove(&f, 0, 1);
114                 strbuf_setlen(&f, f.len - 1);
115         }
116
117         get_sane_name(&mi->name, &f, &mi->email);
118         strbuf_release(&f);
119 }
120
121 static void handle_header(struct strbuf **out, const struct strbuf *line)
122 {
123         if (!*out) {
124                 *out = xmalloc(sizeof(struct strbuf));
125                 strbuf_init(*out, line->len);
126         } else
127                 strbuf_reset(*out);
128
129         strbuf_addbuf(*out, line);
130 }
131
132 /* NOTE NOTE NOTE.  We do not claim we do full MIME.  We just attempt
133  * to have enough heuristics to grok MIME encoded patches often found
134  * on our mailing lists.  For example, we do not even treat header lines
135  * case insensitively.
136  */
137
138 static int slurp_attr(const char *line, const char *name, struct strbuf *attr)
139 {
140         const char *ends, *ap = strcasestr(line, name);
141         size_t sz;
142
143         strbuf_setlen(attr, 0);
144         if (!ap)
145                 return 0;
146         ap += strlen(name);
147         if (*ap == '"') {
148                 ap++;
149                 ends = "\"";
150         }
151         else
152                 ends = "; \t";
153         sz = strcspn(ap, ends);
154         strbuf_add(attr, ap, sz);
155         return 1;
156 }
157
158 static void handle_content_type(struct mailinfo *mi, struct strbuf *line)
159 {
160         struct strbuf *boundary = xmalloc(sizeof(struct strbuf));
161         strbuf_init(boundary, line->len);
162
163         if (slurp_attr(line->buf, "boundary=", boundary)) {
164                 strbuf_insert(boundary, 0, "--", 2);
165                 if (++mi->content_top >= &mi->content[MAX_BOUNDARIES]) {
166                         error("Too many boundaries to handle");
167                         mi->input_error = -1;
168                         mi->content_top = &mi->content[MAX_BOUNDARIES] - 1;
169                         return;
170                 }
171                 *(mi->content_top) = boundary;
172                 boundary = NULL;
173         }
174         slurp_attr(line->buf, "charset=", &mi->charset);
175
176         if (boundary) {
177                 strbuf_release(boundary);
178                 free(boundary);
179         }
180 }
181
182 static void handle_message_id(struct mailinfo *mi, const struct strbuf *line)
183 {
184         if (mi->add_message_id)
185                 mi->message_id = strdup(line->buf);
186 }
187
188 static void handle_content_transfer_encoding(struct mailinfo *mi,
189                                              const struct strbuf *line)
190 {
191         if (strcasestr(line->buf, "base64"))
192                 mi->transfer_encoding = TE_BASE64;
193         else if (strcasestr(line->buf, "quoted-printable"))
194                 mi->transfer_encoding = TE_QP;
195         else
196                 mi->transfer_encoding = TE_DONTCARE;
197 }
198
199 static int is_multipart_boundary(struct mailinfo *mi, const struct strbuf *line)
200 {
201         struct strbuf *content_top = *(mi->content_top);
202
203         return ((content_top->len <= line->len) &&
204                 !memcmp(line->buf, content_top->buf, content_top->len));
205 }
206
207 static void cleanup_subject(struct mailinfo *mi, struct strbuf *subject)
208 {
209         size_t at = 0;
210
211         while (at < subject->len) {
212                 char *pos;
213                 size_t remove;
214
215                 switch (subject->buf[at]) {
216                 case 'r': case 'R':
217                         if (subject->len <= at + 3)
218                                 break;
219                         if ((subject->buf[at + 1] == 'e' ||
220                              subject->buf[at + 1] == 'E') &&
221                             subject->buf[at + 2] == ':') {
222                                 strbuf_remove(subject, at, 3);
223                                 continue;
224                         }
225                         at++;
226                         break;
227                 case ' ': case '\t': case ':':
228                         strbuf_remove(subject, at, 1);
229                         continue;
230                 case '[':
231                         pos = strchr(subject->buf + at, ']');
232                         if (!pos)
233                                 break;
234                         remove = pos - subject->buf + at + 1;
235                         if (!mi->keep_non_patch_brackets_in_subject ||
236                             (7 <= remove &&
237                              memmem(subject->buf + at, remove, "PATCH", 5)))
238                                 strbuf_remove(subject, at, remove);
239                         else {
240                                 at += remove;
241                                 /*
242                                  * If the input had a space after the ], keep
243                                  * it.  We don't bother with finding the end of
244                                  * the space, since we later normalize it
245                                  * anyway.
246                                  */
247                                 if (isspace(subject->buf[at]))
248                                         at += 1;
249                         }
250                         continue;
251                 }
252                 break;
253         }
254         strbuf_trim(subject);
255 }
256
257 #define MAX_HDR_PARSED 10
258 static const char *header[MAX_HDR_PARSED] = {
259         "From","Subject","Date",
260 };
261
262 static inline int cmp_header(const struct strbuf *line, const char *hdr)
263 {
264         int len = strlen(hdr);
265         return !strncasecmp(line->buf, hdr, len) && line->len > len &&
266                         line->buf[len] == ':' && isspace(line->buf[len + 1]);
267 }
268
269 static int is_format_patch_separator(const char *line, int len)
270 {
271         static const char SAMPLE[] =
272                 "From e6807f3efca28b30decfecb1732a56c7db1137ee Mon Sep 17 00:00:00 2001\n";
273         const char *cp;
274
275         if (len != strlen(SAMPLE))
276                 return 0;
277         if (!skip_prefix(line, "From ", &cp))
278                 return 0;
279         if (strspn(cp, "0123456789abcdef") != 40)
280                 return 0;
281         cp += 40;
282         return !memcmp(SAMPLE + (cp - line), cp, strlen(SAMPLE) - (cp - line));
283 }
284
285 static struct strbuf *decode_q_segment(const struct strbuf *q_seg, int rfc2047)
286 {
287         const char *in = q_seg->buf;
288         int c;
289         struct strbuf *out = xmalloc(sizeof(struct strbuf));
290         strbuf_init(out, q_seg->len);
291
292         while ((c = *in++) != 0) {
293                 if (c == '=') {
294                         int d = *in++;
295                         if (d == '\n' || !d)
296                                 break; /* drop trailing newline */
297                         strbuf_addch(out, (hexval(d) << 4) | hexval(*in++));
298                         continue;
299                 }
300                 if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
301                         c = 0x20;
302                 strbuf_addch(out, c);
303         }
304         return out;
305 }
306
307 static struct strbuf *decode_b_segment(const struct strbuf *b_seg)
308 {
309         /* Decode in..ep, possibly in-place to ot */
310         int c, pos = 0, acc = 0;
311         const char *in = b_seg->buf;
312         struct strbuf *out = xmalloc(sizeof(struct strbuf));
313         strbuf_init(out, b_seg->len);
314
315         while ((c = *in++) != 0) {
316                 if (c == '+')
317                         c = 62;
318                 else if (c == '/')
319                         c = 63;
320                 else if ('A' <= c && c <= 'Z')
321                         c -= 'A';
322                 else if ('a' <= c && c <= 'z')
323                         c -= 'a' - 26;
324                 else if ('0' <= c && c <= '9')
325                         c -= '0' - 52;
326                 else
327                         continue; /* garbage */
328                 switch (pos++) {
329                 case 0:
330                         acc = (c << 2);
331                         break;
332                 case 1:
333                         strbuf_addch(out, (acc | (c >> 4)));
334                         acc = (c & 15) << 4;
335                         break;
336                 case 2:
337                         strbuf_addch(out, (acc | (c >> 2)));
338                         acc = (c & 3) << 6;
339                         break;
340                 case 3:
341                         strbuf_addch(out, (acc | c));
342                         acc = pos = 0;
343                         break;
344                 }
345         }
346         return out;
347 }
348
349 static int convert_to_utf8(struct mailinfo *mi,
350                            struct strbuf *line, const char *charset)
351 {
352         char *out;
353
354         if (!mi->metainfo_charset || !charset || !*charset)
355                 return 0;
356
357         if (same_encoding(mi->metainfo_charset, charset))
358                 return 0;
359         out = reencode_string(line->buf, mi->metainfo_charset, charset);
360         if (!out) {
361                 mi->input_error = -1;
362                 return error("cannot convert from %s to %s",
363                              charset, mi->metainfo_charset);
364         }
365         strbuf_attach(line, out, strlen(out), strlen(out));
366         return 0;
367 }
368
369 static void decode_header(struct mailinfo *mi, struct strbuf *it)
370 {
371         char *in, *ep, *cp;
372         struct strbuf outbuf = STRBUF_INIT, *dec;
373         struct strbuf charset_q = STRBUF_INIT, piecebuf = STRBUF_INIT;
374         int found_error = 1; /* pessimism */
375
376         in = it->buf;
377         while (in - it->buf <= it->len && (ep = strstr(in, "=?")) != NULL) {
378                 int encoding;
379                 strbuf_reset(&charset_q);
380                 strbuf_reset(&piecebuf);
381
382                 if (in != ep) {
383                         /*
384                          * We are about to process an encoded-word
385                          * that begins at ep, but there is something
386                          * before the encoded word.
387                          */
388                         char *scan;
389                         for (scan = in; scan < ep; scan++)
390                                 if (!isspace(*scan))
391                                         break;
392
393                         if (scan != ep || in == it->buf) {
394                                 /*
395                                  * We should not lose that "something",
396                                  * unless we have just processed an
397                                  * encoded-word, and there is only LWS
398                                  * before the one we are about to process.
399                                  */
400                                 strbuf_add(&outbuf, in, ep - in);
401                         }
402                 }
403                 /* E.g.
404                  * ep : "=?iso-2022-jp?B?GyR...?= foo"
405                  * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
406                  */
407                 ep += 2;
408
409                 if (ep - it->buf >= it->len || !(cp = strchr(ep, '?')))
410                         goto release_return;
411
412                 if (cp + 3 - it->buf > it->len)
413                         goto release_return;
414                 strbuf_add(&charset_q, ep, cp - ep);
415
416                 encoding = cp[1];
417                 if (!encoding || cp[2] != '?')
418                         goto release_return;
419                 ep = strstr(cp + 3, "?=");
420                 if (!ep)
421                         goto release_return;
422                 strbuf_add(&piecebuf, cp + 3, ep - cp - 3);
423                 switch (tolower(encoding)) {
424                 default:
425                         goto release_return;
426                 case 'b':
427                         dec = decode_b_segment(&piecebuf);
428                         break;
429                 case 'q':
430                         dec = decode_q_segment(&piecebuf, 1);
431                         break;
432                 }
433                 if (convert_to_utf8(mi, dec, charset_q.buf))
434                         goto release_return;
435
436                 strbuf_addbuf(&outbuf, dec);
437                 strbuf_release(dec);
438                 free(dec);
439                 in = ep + 2;
440         }
441         strbuf_addstr(&outbuf, in);
442         strbuf_reset(it);
443         strbuf_addbuf(it, &outbuf);
444         found_error = 0;
445 release_return:
446         strbuf_release(&outbuf);
447         strbuf_release(&charset_q);
448         strbuf_release(&piecebuf);
449
450         if (found_error)
451                 mi->input_error = -1;
452 }
453
454 static int check_header(struct mailinfo *mi,
455                         const struct strbuf *line,
456                         struct strbuf *hdr_data[], int overwrite)
457 {
458         int i, ret = 0, len;
459         struct strbuf sb = STRBUF_INIT;
460
461         /* search for the interesting parts */
462         for (i = 0; header[i]; i++) {
463                 int len = strlen(header[i]);
464                 if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) {
465                         /* Unwrap inline B and Q encoding, and optionally
466                          * normalize the meta information to utf8.
467                          */
468                         strbuf_add(&sb, line->buf + len + 2, line->len - len - 2);
469                         decode_header(mi, &sb);
470                         handle_header(&hdr_data[i], &sb);
471                         ret = 1;
472                         goto check_header_out;
473                 }
474         }
475
476         /* Content stuff */
477         if (cmp_header(line, "Content-Type")) {
478                 len = strlen("Content-Type: ");
479                 strbuf_add(&sb, line->buf + len, line->len - len);
480                 decode_header(mi, &sb);
481                 strbuf_insert(&sb, 0, "Content-Type: ", len);
482                 handle_content_type(mi, &sb);
483                 ret = 1;
484                 goto check_header_out;
485         }
486         if (cmp_header(line, "Content-Transfer-Encoding")) {
487                 len = strlen("Content-Transfer-Encoding: ");
488                 strbuf_add(&sb, line->buf + len, line->len - len);
489                 decode_header(mi, &sb);
490                 handle_content_transfer_encoding(mi, &sb);
491                 ret = 1;
492                 goto check_header_out;
493         }
494         if (cmp_header(line, "Message-Id")) {
495                 len = strlen("Message-Id: ");
496                 strbuf_add(&sb, line->buf + len, line->len - len);
497                 decode_header(mi, &sb);
498                 handle_message_id(mi, &sb);
499                 ret = 1;
500                 goto check_header_out;
501         }
502
503         /* for inbody stuff */
504         if (starts_with(line->buf, ">From") && isspace(line->buf[5])) {
505                 ret = is_format_patch_separator(line->buf + 1, line->len - 1);
506                 goto check_header_out;
507         }
508         if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
509                 for (i = 0; header[i]; i++) {
510                         if (!strcmp("Subject", header[i])) {
511                                 handle_header(&hdr_data[i], line);
512                                 ret = 1;
513                                 goto check_header_out;
514                         }
515                 }
516         }
517
518 check_header_out:
519         strbuf_release(&sb);
520         return ret;
521 }
522
523 static void decode_transfer_encoding(struct mailinfo *mi, struct strbuf *line)
524 {
525         struct strbuf *ret;
526
527         switch (mi->transfer_encoding) {
528         case TE_QP:
529                 ret = decode_q_segment(line, 0);
530                 break;
531         case TE_BASE64:
532                 ret = decode_b_segment(line);
533                 break;
534         case TE_DONTCARE:
535         default:
536                 return;
537         }
538         strbuf_reset(line);
539         strbuf_addbuf(line, ret);
540         strbuf_release(ret);
541         free(ret);
542 }
543
544 static inline int patchbreak(const struct strbuf *line)
545 {
546         size_t i;
547
548         /* Beginning of a "diff -" header? */
549         if (starts_with(line->buf, "diff -"))
550                 return 1;
551
552         /* CVS "Index: " line? */
553         if (starts_with(line->buf, "Index: "))
554                 return 1;
555
556         /*
557          * "--- <filename>" starts patches without headers
558          * "---<sp>*" is a manual separator
559          */
560         if (line->len < 4)
561                 return 0;
562
563         if (starts_with(line->buf, "---")) {
564                 /* space followed by a filename? */
565                 if (line->buf[3] == ' ' && !isspace(line->buf[4]))
566                         return 1;
567                 /* Just whitespace? */
568                 for (i = 3; i < line->len; i++) {
569                         unsigned char c = line->buf[i];
570                         if (c == '\n')
571                                 return 1;
572                         if (!isspace(c))
573                                 break;
574                 }
575                 return 0;
576         }
577         return 0;
578 }
579
580 static int is_scissors_line(const struct strbuf *line)
581 {
582         size_t i, len = line->len;
583         int scissors = 0, gap = 0;
584         int first_nonblank = -1;
585         int last_nonblank = 0, visible, perforation = 0, in_perforation = 0;
586         const char *buf = line->buf;
587
588         for (i = 0; i < len; i++) {
589                 if (isspace(buf[i])) {
590                         if (in_perforation) {
591                                 perforation++;
592                                 gap++;
593                         }
594                         continue;
595                 }
596                 last_nonblank = i;
597                 if (first_nonblank < 0)
598                         first_nonblank = i;
599                 if (buf[i] == '-') {
600                         in_perforation = 1;
601                         perforation++;
602                         continue;
603                 }
604                 if (i + 1 < len &&
605                     (!memcmp(buf + i, ">8", 2) || !memcmp(buf + i, "8<", 2) ||
606                      !memcmp(buf + i, ">%", 2) || !memcmp(buf + i, "%<", 2))) {
607                         in_perforation = 1;
608                         perforation += 2;
609                         scissors += 2;
610                         i++;
611                         continue;
612                 }
613                 in_perforation = 0;
614         }
615
616         /*
617          * The mark must be at least 8 bytes long (e.g. "-- >8 --").
618          * Even though there can be arbitrary cruft on the same line
619          * (e.g. "cut here"), in order to avoid misidentification, the
620          * perforation must occupy more than a third of the visible
621          * width of the line, and dashes and scissors must occupy more
622          * than half of the perforation.
623          */
624
625         visible = last_nonblank - first_nonblank + 1;
626         return (scissors && 8 <= visible &&
627                 visible < perforation * 3 &&
628                 gap * 2 < perforation);
629 }
630
631 static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
632 {
633         assert(!mi->filter_stage);
634
635         if (mi->header_stage) {
636                 if (!line->len || (line->len == 1 && line->buf[0] == '\n'))
637                         return 0;
638         }
639
640         if (mi->use_inbody_headers && mi->header_stage) {
641                 mi->header_stage = check_header(mi, line, mi->s_hdr_data, 0);
642                 if (mi->header_stage)
643                         return 0;
644         } else
645                 /* Only trim the first (blank) line of the commit message
646                  * when ignoring in-body headers.
647                  */
648                 mi->header_stage = 0;
649
650         /* normalize the log message to UTF-8. */
651         if (convert_to_utf8(mi, line, mi->charset.buf))
652                 return 0; /* mi->input_error already set */
653
654         if (mi->use_scissors && is_scissors_line(line)) {
655                 int i;
656
657                 strbuf_setlen(&mi->log_message, 0);
658                 mi->header_stage = 1;
659
660                 /*
661                  * We may have already read "secondary headers"; purge
662                  * them to give ourselves a clean restart.
663                  */
664                 for (i = 0; header[i]; i++) {
665                         if (mi->s_hdr_data[i])
666                                 strbuf_release(mi->s_hdr_data[i]);
667                         mi->s_hdr_data[i] = NULL;
668                 }
669                 return 0;
670         }
671
672         if (patchbreak(line)) {
673                 if (mi->message_id)
674                         strbuf_addf(&mi->log_message,
675                                     "Message-Id: %s\n", mi->message_id);
676                 return 1;
677         }
678
679         strbuf_addbuf(&mi->log_message, line);
680         return 0;
681 }
682
683 static void handle_patch(struct mailinfo *mi, const struct strbuf *line)
684 {
685         fwrite(line->buf, 1, line->len, mi->patchfile);
686         mi->patch_lines++;
687 }
688
689 static void handle_filter(struct mailinfo *mi, struct strbuf *line)
690 {
691         switch (mi->filter_stage) {
692         case 0:
693                 if (!handle_commit_msg(mi, line))
694                         break;
695                 mi->filter_stage++;
696         case 1:
697                 handle_patch(mi, line);
698                 break;
699         }
700 }
701
702 static int is_rfc2822_header(const struct strbuf *line)
703 {
704         /*
705          * The section that defines the loosest possible
706          * field name is "3.6.8 Optional fields".
707          *
708          * optional-field = field-name ":" unstructured CRLF
709          * field-name = 1*ftext
710          * ftext = %d33-57 / %59-126
711          */
712         int ch;
713         char *cp = line->buf;
714
715         /* Count mbox From headers as headers */
716         if (starts_with(cp, "From ") || starts_with(cp, ">From "))
717                 return 1;
718
719         while ((ch = *cp++)) {
720                 if (ch == ':')
721                         return 1;
722                 if ((33 <= ch && ch <= 57) ||
723                     (59 <= ch && ch <= 126))
724                         continue;
725                 break;
726         }
727         return 0;
728 }
729
730 static int read_one_header_line(struct strbuf *line, FILE *in)
731 {
732         struct strbuf continuation = STRBUF_INIT;
733
734         /* Get the first part of the line. */
735         if (strbuf_getline_lf(line, in))
736                 return 0;
737
738         /*
739          * Is it an empty line or not a valid rfc2822 header?
740          * If so, stop here, and return false ("not a header")
741          */
742         strbuf_rtrim(line);
743         if (!line->len || !is_rfc2822_header(line)) {
744                 /* Re-add the newline */
745                 strbuf_addch(line, '\n');
746                 return 0;
747         }
748
749         /*
750          * Now we need to eat all the continuation lines..
751          * Yuck, 2822 header "folding"
752          */
753         for (;;) {
754                 int peek;
755
756                 peek = fgetc(in); ungetc(peek, in);
757                 if (peek != ' ' && peek != '\t')
758                         break;
759                 if (strbuf_getline_lf(&continuation, in))
760                         break;
761                 continuation.buf[0] = ' ';
762                 strbuf_rtrim(&continuation);
763                 strbuf_addbuf(line, &continuation);
764         }
765         strbuf_release(&continuation);
766
767         return 1;
768 }
769
770 static int find_boundary(struct mailinfo *mi, struct strbuf *line)
771 {
772         while (!strbuf_getline_lf(line, mi->input)) {
773                 if (*(mi->content_top) && is_multipart_boundary(mi, line))
774                         return 1;
775         }
776         return 0;
777 }
778
779 static int handle_boundary(struct mailinfo *mi, struct strbuf *line)
780 {
781         struct strbuf newline = STRBUF_INIT;
782
783         strbuf_addch(&newline, '\n');
784 again:
785         if (line->len >= (*(mi->content_top))->len + 2 &&
786             !memcmp(line->buf + (*(mi->content_top))->len, "--", 2)) {
787                 /* we hit an end boundary */
788                 /* pop the current boundary off the stack */
789                 strbuf_release(*(mi->content_top));
790                 free(*(mi->content_top));
791                 *(mi->content_top) = NULL;
792
793                 /* technically won't happen as is_multipart_boundary()
794                    will fail first.  But just in case..
795                  */
796                 if (--mi->content_top < mi->content) {
797                         error("Detected mismatched boundaries, can't recover");
798                         mi->input_error = -1;
799                         mi->content_top = mi->content;
800                         return 0;
801                 }
802                 handle_filter(mi, &newline);
803                 strbuf_release(&newline);
804                 if (mi->input_error)
805                         return 0;
806
807                 /* skip to the next boundary */
808                 if (!find_boundary(mi, line))
809                         return 0;
810                 goto again;
811         }
812
813         /* set some defaults */
814         mi->transfer_encoding = TE_DONTCARE;
815         strbuf_reset(&mi->charset);
816
817         /* slurp in this section's info */
818         while (read_one_header_line(line, mi->input))
819                 check_header(mi, line, mi->p_hdr_data, 0);
820
821         strbuf_release(&newline);
822         /* replenish line */
823         if (strbuf_getline_lf(line, mi->input))
824                 return 0;
825         strbuf_addch(line, '\n');
826         return 1;
827 }
828
829 static void handle_body(struct mailinfo *mi, struct strbuf *line)
830 {
831         struct strbuf prev = STRBUF_INIT;
832
833         /* Skip up to the first boundary */
834         if (*(mi->content_top)) {
835                 if (!find_boundary(mi, line))
836                         goto handle_body_out;
837         }
838
839         do {
840                 /* process any boundary lines */
841                 if (*(mi->content_top) && is_multipart_boundary(mi, line)) {
842                         /* flush any leftover */
843                         if (prev.len) {
844                                 handle_filter(mi, &prev);
845                                 strbuf_reset(&prev);
846                         }
847                         if (!handle_boundary(mi, line))
848                                 goto handle_body_out;
849                 }
850
851                 /* Unwrap transfer encoding */
852                 decode_transfer_encoding(mi, line);
853
854                 switch (mi->transfer_encoding) {
855                 case TE_BASE64:
856                 case TE_QP:
857                 {
858                         struct strbuf **lines, **it, *sb;
859
860                         /* Prepend any previous partial lines */
861                         strbuf_insert(line, 0, prev.buf, prev.len);
862                         strbuf_reset(&prev);
863
864                         /*
865                          * This is a decoded line that may contain
866                          * multiple new lines.  Pass only one chunk
867                          * at a time to handle_filter()
868                          */
869                         lines = strbuf_split(line, '\n');
870                         for (it = lines; (sb = *it); it++) {
871                                 if (*(it + 1) == NULL) /* The last line */
872                                         if (sb->buf[sb->len - 1] != '\n') {
873                                                 /* Partial line, save it for later. */
874                                                 strbuf_addbuf(&prev, sb);
875                                                 break;
876                                         }
877                                 handle_filter(mi, sb);
878                         }
879                         /*
880                          * The partial chunk is saved in "prev" and will be
881                          * appended by the next iteration of read_line_with_nul().
882                          */
883                         strbuf_list_free(lines);
884                         break;
885                 }
886                 default:
887                         handle_filter(mi, line);
888                 }
889
890                 if (mi->input_error)
891                         break;
892         } while (!strbuf_getwholeline(line, mi->input, '\n'));
893
894 handle_body_out:
895         strbuf_release(&prev);
896 }
897
898 static void output_header_lines(FILE *fout, const char *hdr, const struct strbuf *data)
899 {
900         const char *sp = data->buf;
901         while (1) {
902                 char *ep = strchr(sp, '\n');
903                 int len;
904                 if (!ep)
905                         len = strlen(sp);
906                 else
907                         len = ep - sp;
908                 fprintf(fout, "%s: %.*s\n", hdr, len, sp);
909                 if (!ep)
910                         break;
911                 sp = ep + 1;
912         }
913 }
914
915 static void handle_info(struct mailinfo *mi)
916 {
917         struct strbuf *hdr;
918         int i;
919
920         for (i = 0; header[i]; i++) {
921                 /* only print inbody headers if we output a patch file */
922                 if (mi->patch_lines && mi->s_hdr_data[i])
923                         hdr = mi->s_hdr_data[i];
924                 else if (mi->p_hdr_data[i])
925                         hdr = mi->p_hdr_data[i];
926                 else
927                         continue;
928
929                 if (!strcmp(header[i], "Subject")) {
930                         if (!mi->keep_subject) {
931                                 cleanup_subject(mi, hdr);
932                                 cleanup_space(hdr);
933                         }
934                         output_header_lines(mi->output, "Subject", hdr);
935                 } else if (!strcmp(header[i], "From")) {
936                         cleanup_space(hdr);
937                         handle_from(mi, hdr);
938                         fprintf(mi->output, "Author: %s\n", mi->name.buf);
939                         fprintf(mi->output, "Email: %s\n", mi->email.buf);
940                 } else {
941                         cleanup_space(hdr);
942                         fprintf(mi->output, "%s: %s\n", header[i], hdr->buf);
943                 }
944         }
945         fprintf(mi->output, "\n");
946 }
947
948 int mailinfo(struct mailinfo *mi, const char *msg, const char *patch)
949 {
950         FILE *cmitmsg;
951         int peek;
952         struct strbuf line = STRBUF_INIT;
953
954         cmitmsg = fopen(msg, "w");
955         if (!cmitmsg) {
956                 perror(msg);
957                 return -1;
958         }
959         mi->patchfile = fopen(patch, "w");
960         if (!mi->patchfile) {
961                 perror(patch);
962                 fclose(cmitmsg);
963                 return -1;
964         }
965
966         mi->p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->p_hdr_data)));
967         mi->s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->s_hdr_data)));
968
969         do {
970                 peek = fgetc(mi->input);
971         } while (isspace(peek));
972         ungetc(peek, mi->input);
973
974         /* process the email header */
975         while (read_one_header_line(&line, mi->input))
976                 check_header(mi, &line, mi->p_hdr_data, 1);
977
978         handle_body(mi, &line);
979         fwrite(mi->log_message.buf, 1, mi->log_message.len, cmitmsg);
980         fclose(cmitmsg);
981         fclose(mi->patchfile);
982
983         handle_info(mi);
984         strbuf_release(&line);
985         return mi->input_error;
986 }
987
988 static int git_mailinfo_config(const char *var, const char *value, void *mi_)
989 {
990         struct mailinfo *mi = mi_;
991
992         if (!starts_with(var, "mailinfo."))
993                 return git_default_config(var, value, NULL);
994         if (!strcmp(var, "mailinfo.scissors")) {
995                 mi->use_scissors = git_config_bool(var, value);
996                 return 0;
997         }
998         /* perhaps others here */
999         return 0;
1000 }
1001
1002 void setup_mailinfo(struct mailinfo *mi)
1003 {
1004         memset(mi, 0, sizeof(*mi));
1005         strbuf_init(&mi->name, 0);
1006         strbuf_init(&mi->email, 0);
1007         strbuf_init(&mi->charset, 0);
1008         strbuf_init(&mi->log_message, 0);
1009         mi->header_stage = 1;
1010         mi->use_inbody_headers = 1;
1011         mi->content_top = mi->content;
1012         git_config(git_mailinfo_config, mi);
1013 }
1014
1015 void clear_mailinfo(struct mailinfo *mi)
1016 {
1017         int i;
1018
1019         strbuf_release(&mi->name);
1020         strbuf_release(&mi->email);
1021         strbuf_release(&mi->charset);
1022         free(mi->message_id);
1023
1024         for (i = 0; mi->p_hdr_data[i]; i++)
1025                 strbuf_release(mi->p_hdr_data[i]);
1026         free(mi->p_hdr_data);
1027         for (i = 0; mi->s_hdr_data[i]; i++)
1028                 strbuf_release(mi->s_hdr_data[i]);
1029         free(mi->s_hdr_data);
1030
1031         while (mi->content < mi->content_top) {
1032                 free(*(mi->content_top));
1033                 mi->content_top--;
1034         }
1035
1036         strbuf_release(&mi->log_message);
1037 }