git

1
#include "cache.h"
2
#include "config.h"
3
#include "utf8.h"
4
#include "strbuf.h"
5
#include "mailinfo.h"
6

7
static void cleanup_space(struct strbuf *sb)
8
{
9
	size_t pos, cnt;
10
	for (pos = 0; pos < sb->len; pos++) {
11
		if (isspace(sb->buf[pos])) {
12
			sb->buf[pos] = ' ';
13
			for (cnt = 0; isspace(sb->buf[pos + cnt + 1]); cnt++);
14
			strbuf_remove(sb, pos + 1, cnt);
15
		}
16
	}
17
}
18

19
static void get_sane_name(struct strbuf *out, struct strbuf *name, struct strbuf *email)
20
{
21
	struct strbuf *src = name;
22
	if (name->len < 3 || 60 < name->len || strchr(name->buf, '@') ||
23
		strchr(name->buf, '<') || strchr(name->buf, '>'))
24
		src = email;
25
	else if (name == out)
26
		return;
27
	strbuf_reset(out);
28
	strbuf_addbuf(out, src);
29
}
30

31
static void parse_bogus_from(struct mailinfo *mi, const struct strbuf *line)
32
{
33
	/* John Doe <johndoe> */
34

35
	char *bra, *ket;
36
	/* This is fallback, so do not bother if we already have an
37
	 * e-mail address.
38
	 */
39
	if (mi->email.len)
40
		return;
41

42
	bra = strchr(line->buf, '<');
43
	if (!bra)
44
		return;
45
	ket = strchr(bra, '>');
46
	if (!ket)
47
		return;
48

49
	strbuf_reset(&mi->email);
50
	strbuf_add(&mi->email, bra + 1, ket - bra - 1);
51

52
	strbuf_reset(&mi->name);
53
	strbuf_add(&mi->name, line->buf, bra - line->buf);
54
	strbuf_trim(&mi->name);
55
	get_sane_name(&mi->name, &mi->name, &mi->email);
56
}
57

58
static const char *unquote_comment(struct strbuf *outbuf, const char *in)
59
{
60
	int c;
61
	int take_next_literally = 0;
62

63
	strbuf_addch(outbuf, '(');
64

65
	while ((c = *in++) != 0) {
66
		if (take_next_literally == 1) {
67
			take_next_literally = 0;
68
		} else {
69
			switch (c) {
70
			case '\\':
71
				take_next_literally = 1;
72
				continue;
73
			case '(':
74
				in = unquote_comment(outbuf, in);
75
				continue;
76
			case ')':
77
				strbuf_addch(outbuf, ')');
78
				return in;
79
			}
80
		}
81

82
		strbuf_addch(outbuf, c);
83
	}
84

85
	return in;
86
}
87

88
static const char *unquote_quoted_string(struct strbuf *outbuf, const char *in)
89
{
90
	int c;
91
	int take_next_literally = 0;
92

93
	while ((c = *in++) != 0) {
94
		if (take_next_literally == 1) {
95
			take_next_literally = 0;
96
		} else {
97
			switch (c) {
98
			case '\\':
99
				take_next_literally = 1;
100
				continue;
101
			case '"':
102
				return in;
103
			}
104
		}
105

106
		strbuf_addch(outbuf, c);
107
	}
108

109
	return in;
110
}
111

112
static void unquote_quoted_pair(struct strbuf *line)
113
{
114
	struct strbuf outbuf;
115
	const char *in = line->buf;
116
	int c;
117

118
	strbuf_init(&outbuf, line->len);
119

120
	while ((c = *in++) != 0) {
121
		switch (c) {
122
		case '"':
123
			in = unquote_quoted_string(&outbuf, in);
124
			continue;
125
		case '(':
126
			in = unquote_comment(&outbuf, in);
127
			continue;
128
		}
129

130
		strbuf_addch(&outbuf, c);
131
	}
132

133
	strbuf_swap(&outbuf, line);
134
	strbuf_release(&outbuf);
135

136
}
137

138
static void handle_from(struct mailinfo *mi, const struct strbuf *from)
139
{
140
	char *at;
141
	size_t el;
142
	struct strbuf f;
143

144
	strbuf_init(&f, from->len);
145
	strbuf_addbuf(&f, from);
146

147
	unquote_quoted_pair(&f);
148

149
	at = strchr(f.buf, '@');
150
	if (!at) {
151
		parse_bogus_from(mi, from);
152
		goto out;
153
	}
154

155
	/*
156
	 * If we already have one email, don't take any confusing lines
157
	 */
158
	if (mi->email.len && strchr(at + 1, '@'))
159
		goto out;
160

161
	/* Pick up the string around '@', possibly delimited with <>
162
	 * pair; that is the email part.
163
	 */
164
	while (at > f.buf) {
165
		char c = at[-1];
166
		if (isspace(c))
167
			break;
168
		if (c == '<') {
169
			at[-1] = ' ';
170
			break;
171
		}
172
		at--;
173
	}
174
	el = strcspn(at, " \n\t\r\v\f>");
175
	strbuf_reset(&mi->email);
176
	strbuf_add(&mi->email, at, el);
177
	strbuf_remove(&f, at - f.buf, el + (at[el] ? 1 : 0));
178

179
	/* The remainder is name.  It could be
180
	 *
181
	 * - "John Doe <john.doe@xz>"			(a), or
182
	 * - "john.doe@xz (John Doe)"			(b), or
183
	 * - "John (zzz) Doe <john.doe@xz> (Comment)"	(c)
184
	 *
185
	 * but we have removed the email part, so
186
	 *
187
	 * - remove extra spaces which could stay after email (case 'c'), and
188
	 * - trim from both ends, possibly removing the () pair at the end
189
	 *   (cases 'a' and 'b').
190
	 */
191
	cleanup_space(&f);
192
	strbuf_trim(&f);
193
	if (f.buf[0] == '(' && f.len && f.buf[f.len - 1] == ')') {
194
		strbuf_remove(&f, 0, 1);
195
		strbuf_setlen(&f, f.len - 1);
196
	}
197

198
	get_sane_name(&mi->name, &f, &mi->email);
199
out:
200
	strbuf_release(&f);
201
}
202

203
static void handle_header(struct strbuf **out, const struct strbuf *line)
204
{
205
	if (!*out) {
206
		*out = xmalloc(sizeof(struct strbuf));
207
		strbuf_init(*out, line->len);
208
	} else
209
		strbuf_reset(*out);
210

211
	strbuf_addbuf(*out, line);
212
}
213

214
/* NOTE NOTE NOTE.  We do not claim we do full MIME.  We just attempt
215
 * to have enough heuristics to grok MIME encoded patches often found
216
 * on our mailing lists.  For example, we do not even treat header lines
217
 * case insensitively.
218
 */
219

220
static int slurp_attr(const char *line, const char *name, struct strbuf *attr)
221
{
222
	const char *ends, *ap = strcasestr(line, name);
223
	size_t sz;
224

225
	strbuf_setlen(attr, 0);
226
	if (!ap)
227
		return 0;
228
	ap += strlen(name);
229
	if (*ap == '"') {
230
		ap++;
231
		ends = "\"";
232
	}
233
	else
234
		ends = "; \t";
235
	sz = strcspn(ap, ends);
236
	strbuf_add(attr, ap, sz);
237
	return 1;
238
}
239

240
static int has_attr_value(const char *line, const char *name, const char *value)
241
{
242
	struct strbuf sb = STRBUF_INIT;
243
	int rc = slurp_attr(line, name, &sb) && !strcasecmp(sb.buf, value);
244
	strbuf_release(&sb);
245
	return rc;
246
}
247

248
static void handle_content_type(struct mailinfo *mi, struct strbuf *line)
249
{
250
	struct strbuf *boundary = xmalloc(sizeof(struct strbuf));
251
	strbuf_init(boundary, line->len);
252

253
	mi->format_flowed = has_attr_value(line->buf, "format=", "flowed");
254
	mi->delsp = has_attr_value(line->buf, "delsp=", "yes");
255

256
	if (slurp_attr(line->buf, "boundary=", boundary)) {
257
		strbuf_insert(boundary, 0, "--", 2);
258
		if (++mi->content_top >= &mi->content[MAX_BOUNDARIES]) {
259
			error("Too many boundaries to handle");
260
			mi->input_error = -1;
261
			mi->content_top = &mi->content[MAX_BOUNDARIES] - 1;
262
			return;
263
		}
264
		*(mi->content_top) = boundary;
265
		boundary = NULL;
266
	}
267
	slurp_attr(line->buf, "charset=", &mi->charset);
268

269
	if (boundary) {
270
		strbuf_release(boundary);
271
		free(boundary);
272
	}
273
}
274

275
static void handle_content_transfer_encoding(struct mailinfo *mi,
276
					     const struct strbuf *line)
277
{
278
	if (strcasestr(line->buf, "base64"))
279
		mi->transfer_encoding = TE_BASE64;
280
	else if (strcasestr(line->buf, "quoted-printable"))
281
		mi->transfer_encoding = TE_QP;
282
	else
283
		mi->transfer_encoding = TE_DONTCARE;
284
}
285

286
static int is_multipart_boundary(struct mailinfo *mi, const struct strbuf *line)
287
{
288
	struct strbuf *content_top = *(mi->content_top);
289

290
	return ((content_top->len <= line->len) &&
291
		!memcmp(line->buf, content_top->buf, content_top->len));
292
}
293

294
static void cleanup_subject(struct mailinfo *mi, struct strbuf *subject)
295
{
296
	size_t at = 0;
297

298
	while (at < subject->len) {
299
		char *pos;
300
		size_t remove;
301

302
		switch (subject->buf[at]) {
303
		case 'r': case 'R':
304
			if (subject->len <= at + 3)
305
				break;
306
			if ((subject->buf[at + 1] == 'e' ||
307
			     subject->buf[at + 1] == 'E') &&
308
			    subject->buf[at + 2] == ':') {
309
				strbuf_remove(subject, at, 3);
310
				continue;
311
			}
312
			at++;
313
			break;
314
		case ' ': case '\t': case ':':
315
			strbuf_remove(subject, at, 1);
316
			continue;
317
		case '[':
318
			pos = strchr(subject->buf + at, ']');
319
			if (!pos)
320
				break;
321
			remove = pos - subject->buf + at + 1;
322
			if (!mi->keep_non_patch_brackets_in_subject ||
323
			    (7 <= remove &&
324
			     memmem(subject->buf + at, remove, "PATCH", 5)))
325
				strbuf_remove(subject, at, remove);
326
			else {
327
				at += remove;
328
				/*
329
				 * If the input had a space after the ], keep
330
				 * it.  We don't bother with finding the end of
331
				 * the space, since we later normalize it
332
				 * anyway.
333
				 */
334
				if (isspace(subject->buf[at]))
335
					at += 1;
336
			}
337
			continue;
338
		}
339
		break;
340
	}
341
	strbuf_trim(subject);
342
}
343

344
#define MAX_HDR_PARSED 10
345
static const char *header[MAX_HDR_PARSED] = {
346
	"From","Subject","Date",
347
};
348

349
static inline int cmp_header(const struct strbuf *line, const char *hdr)
350
{
351
	int len = strlen(hdr);
352
	return !strncasecmp(line->buf, hdr, len) && line->len > len &&
353
			line->buf[len] == ':' && isspace(line->buf[len + 1]);
354
}
355

356
static int is_format_patch_separator(const char *line, int len)
357
{
358
	static const char SAMPLE[] =
359
		"From e6807f3efca28b30decfecb1732a56c7db1137ee Mon Sep 17 00:00:00 2001\n";
360
	const char *cp;
361

362
	if (len != strlen(SAMPLE))
363
		return 0;
364
	if (!skip_prefix(line, "From ", &cp))
365
		return 0;
366
	if (strspn(cp, "0123456789abcdef") != 40)
367
		return 0;
368
	cp += 40;
369
	return !memcmp(SAMPLE + (cp - line), cp, strlen(SAMPLE) - (cp - line));
370
}
371

372
static struct strbuf *decode_q_segment(const struct strbuf *q_seg, int rfc2047)
373
{
374
	const char *in = q_seg->buf;
375
	int c;
376
	struct strbuf *out = xmalloc(sizeof(struct strbuf));
377
	strbuf_init(out, q_seg->len);
378

379
	while ((c = *in++) != 0) {
380
		if (c == '=') {
381
			int ch, d = *in;
382
			if (d == '\n' || !d)
383
				break; /* drop trailing newline */
384
			ch = hex2chr(in);
385
			if (ch >= 0) {
386
				strbuf_addch(out, ch);
387
				in += 2;
388
				continue;
389
			}
390
			/* garbage -- fall through */
391
		}
392
		if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
393
			c = 0x20;
394
		strbuf_addch(out, c);
395
	}
396
	return out;
397
}
398

399
static struct strbuf *decode_b_segment(const struct strbuf *b_seg)
400
{
401
	/* Decode in..ep, possibly in-place to ot */
402
	int c, pos = 0, acc = 0;
403
	const char *in = b_seg->buf;
404
	struct strbuf *out = xmalloc(sizeof(struct strbuf));
405
	strbuf_init(out, b_seg->len);
406

407
	while ((c = *in++) != 0) {
408
		if (c == '+')
409
			c = 62;
410
		else if (c == '/')
411
			c = 63;
412
		else if ('A' <= c && c <= 'Z')
413
			c -= 'A';
414
		else if ('a' <= c && c <= 'z')
415
			c -= 'a' - 26;
416
		else if ('0' <= c && c <= '9')
417
			c -= '0' - 52;
418
		else
419
			continue; /* garbage */
420
		switch (pos++) {
421
		case 0:
422
			acc = (c << 2);
423
			break;
424
		case 1:
425
			strbuf_addch(out, (acc | (c >> 4)));
426
			acc = (c & 15) << 4;
427
			break;
428
		case 2:
429
			strbuf_addch(out, (acc | (c >> 2)));
430
			acc = (c & 3) << 6;
431
			break;
432
		case 3:
433
			strbuf_addch(out, (acc | c));
434
			acc = pos = 0;
435
			break;
436
		}
437
	}
438
	return out;
439
}
440

441
static int convert_to_utf8(struct mailinfo *mi,
442
			   struct strbuf *line, const char *charset)
443
{
444
	char *out;
445

446
	if (!mi->metainfo_charset || !charset || !*charset)
447
		return 0;
448

449
	if (same_encoding(mi->metainfo_charset, charset))
450
		return 0;
451
	out = reencode_string(line->buf, mi->metainfo_charset, charset);
452
	if (!out) {
453
		mi->input_error = -1;
454
		return error("cannot convert from %s to %s",
455
			     charset, mi->metainfo_charset);
456
	}
457
	strbuf_attach(line, out, strlen(out), strlen(out));
458
	return 0;
459
}
460

461
static void decode_header(struct mailinfo *mi, struct strbuf *it)
462
{
463
	char *in, *ep, *cp;
464
	struct strbuf outbuf = STRBUF_INIT, *dec;
465
	struct strbuf charset_q = STRBUF_INIT, piecebuf = STRBUF_INIT;
466
	int found_error = 1; /* pessimism */
467

468
	in = it->buf;
469
	while (in - it->buf <= it->len && (ep = strstr(in, "=?")) != NULL) {
470
		int encoding;
471
		strbuf_reset(&charset_q);
472
		strbuf_reset(&piecebuf);
473

474
		if (in != ep) {
475
			/*
476
			 * We are about to process an encoded-word
477
			 * that begins at ep, but there is something
478
			 * before the encoded word.
479
			 */
480
			char *scan;
481
			for (scan = in; scan < ep; scan++)
482
				if (!isspace(*scan))
483
					break;
484

485
			if (scan != ep || in == it->buf) {
486
				/*
487
				 * We should not lose that "something",
488
				 * unless we have just processed an
489
				 * encoded-word, and there is only LWS
490
				 * before the one we are about to process.
491
				 */
492
				strbuf_add(&outbuf, in, ep - in);
493
			}
494
		}
495
		/* E.g.
496
		 * ep : "=?iso-2022-jp?B?GyR...?= foo"
497
		 * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
498
		 */
499
		ep += 2;
500

501
		if (ep - it->buf >= it->len || !(cp = strchr(ep, '?')))
502
			goto release_return;
503

504
		if (cp + 3 - it->buf > it->len)
505
			goto release_return;
506
		strbuf_add(&charset_q, ep, cp - ep);
507

508
		encoding = cp[1];
509
		if (!encoding || cp[2] != '?')
510
			goto release_return;
511
		ep = strstr(cp + 3, "?=");
512
		if (!ep)
513
			goto release_return;
514
		strbuf_add(&piecebuf, cp + 3, ep - cp - 3);
515
		switch (tolower(encoding)) {
516
		default:
517
			goto release_return;
518
		case 'b':
519
			dec = decode_b_segment(&piecebuf);
520
			break;
521
		case 'q':
522
			dec = decode_q_segment(&piecebuf, 1);
523
			break;
524
		}
525
		if (convert_to_utf8(mi, dec, charset_q.buf))
526
			goto release_return;
527

528
		strbuf_addbuf(&outbuf, dec);
529
		strbuf_release(dec);
530
		free(dec);
531
		in = ep + 2;
532
	}
533
	strbuf_addstr(&outbuf, in);
534
	strbuf_reset(it);
535
	strbuf_addbuf(it, &outbuf);
536
	found_error = 0;
537
release_return:
538
	strbuf_release(&outbuf);
539
	strbuf_release(&charset_q);
540
	strbuf_release(&piecebuf);
541

542
	if (found_error)
543
		mi->input_error = -1;
544
}
545

546
static int check_header(struct mailinfo *mi,
547
			const struct strbuf *line,
548
			struct strbuf *hdr_data[], int overwrite)
549
{
550
	int i, ret = 0, len;
551
	struct strbuf sb = STRBUF_INIT;
552

553
	/* search for the interesting parts */
554
	for (i = 0; header[i]; i++) {
555
		int len = strlen(header[i]);
556
		if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) {
557
			/* Unwrap inline B and Q encoding, and optionally
558
			 * normalize the meta information to utf8.
559
			 */
560
			strbuf_add(&sb, line->buf + len + 2, line->len - len - 2);
561
			decode_header(mi, &sb);
562
			handle_header(&hdr_data[i], &sb);
563
			ret = 1;
564
			goto check_header_out;
565
		}
566
	}
567

568
	/* Content stuff */
569
	if (cmp_header(line, "Content-Type")) {
570
		len = strlen("Content-Type: ");
571
		strbuf_add(&sb, line->buf + len, line->len - len);
572
		decode_header(mi, &sb);
573
		strbuf_insert(&sb, 0, "Content-Type: ", len);
574
		handle_content_type(mi, &sb);
575
		ret = 1;
576
		goto check_header_out;
577
	}
578
	if (cmp_header(line, "Content-Transfer-Encoding")) {
579
		len = strlen("Content-Transfer-Encoding: ");
580
		strbuf_add(&sb, line->buf + len, line->len - len);
581
		decode_header(mi, &sb);
582
		handle_content_transfer_encoding(mi, &sb);
583
		ret = 1;
584
		goto check_header_out;
585
	}
586
	if (cmp_header(line, "Message-Id")) {
587
		len = strlen("Message-Id: ");
588
		strbuf_add(&sb, line->buf + len, line->len - len);
589
		decode_header(mi, &sb);
590
		if (mi->add_message_id)
591
			mi->message_id = strbuf_detach(&sb, NULL);
592
		ret = 1;
593
		goto check_header_out;
594
	}
595

596
check_header_out:
597
	strbuf_release(&sb);
598
	return ret;
599
}
600

601
/*
602
 * Returns 1 if the given line or any line beginning with the given line is an
603
 * in-body header (that is, check_header will succeed when passed
604
 * mi->s_hdr_data).
605
 */
606
static int is_inbody_header(const struct mailinfo *mi,
607
			    const struct strbuf *line)
608
{
609
	int i;
610
	for (i = 0; header[i]; i++)
611
		if (!mi->s_hdr_data[i] && cmp_header(line, header[i]))
612
			return 1;
613
	return 0;
614
}
615

616
static void decode_transfer_encoding(struct mailinfo *mi, struct strbuf *line)
617
{
618
	struct strbuf *ret;
619

620
	switch (mi->transfer_encoding) {
621
	case TE_QP:
622
		ret = decode_q_segment(line, 0);
623
		break;
624
	case TE_BASE64:
625
		ret = decode_b_segment(line);
626
		break;
627
	case TE_DONTCARE:
628
	default:
629
		return;
630
	}
631
	strbuf_reset(line);
632
	strbuf_addbuf(line, ret);
633
	strbuf_release(ret);
634
	free(ret);
635
}
636

637
static inline int patchbreak(const struct strbuf *line)
638
{
639
	size_t i;
640

641
	/* Beginning of a "diff -" header? */
642
	if (starts_with(line->buf, "diff -"))
643
		return 1;
644

645
	/* CVS "Index: " line? */
646
	if (starts_with(line->buf, "Index: "))
647
		return 1;
648

649
	/*
650
	 * "--- <filename>" starts patches without headers
651
	 * "---<sp>*" is a manual separator
652
	 */
653
	if (line->len < 4)
654
		return 0;
655

656
	if (starts_with(line->buf, "---")) {
657
		/* space followed by a filename? */
658
		if (line->buf[3] == ' ' && !isspace(line->buf[4]))
659
			return 1;
660
		/* Just whitespace? */
661
		for (i = 3; i < line->len; i++) {
662
			unsigned char c = line->buf[i];
663
			if (c == '\n')
664
				return 1;
665
			if (!isspace(c))
666
				break;
667
		}
668
		return 0;
669
	}
670
	return 0;
671
}
672

673
static int is_scissors_line(const char *line)
674
{
675
	const char *c;
676
	int scissors = 0, gap = 0;
677
	const char *first_nonblank = NULL, *last_nonblank = NULL;
678
	int visible, perforation = 0, in_perforation = 0;
679

680
	for (c = line; *c; c++) {
681
		if (isspace(*c)) {
682
			if (in_perforation) {
683
				perforation++;
684
				gap++;
685
			}
686
			continue;
687
		}
688
		last_nonblank = c;
689
		if (first_nonblank == NULL)
690
			first_nonblank = c;
691
		if (*c == '-') {
692
			in_perforation = 1;
693
			perforation++;
694
			continue;
695
		}
696
		if ((!memcmp(c, ">8", 2) || !memcmp(c, "8<", 2) ||
697
		     !memcmp(c, ">%", 2) || !memcmp(c, "%<", 2))) {
698
			in_perforation = 1;
699
			perforation += 2;
700
			scissors += 2;
701
			c++;
702
			continue;
703
		}
704
		in_perforation = 0;
705
	}
706

707
	/*
708
	 * The mark must be at least 8 bytes long (e.g. "-- >8 --").
709
	 * Even though there can be arbitrary cruft on the same line
710
	 * (e.g. "cut here"), in order to avoid misidentification, the
711
	 * perforation must occupy more than a third of the visible
712
	 * width of the line, and dashes and scissors must occupy more
713
	 * than half of the perforation.
714
	 */
715

716
	if (first_nonblank && last_nonblank)
717
		visible = last_nonblank - first_nonblank + 1;
718
	else
719
		visible = 0;
720
	return (scissors && 8 <= visible &&
721
		visible < perforation * 3 &&
722
		gap * 2 < perforation);
723
}
724

725
static void flush_inbody_header_accum(struct mailinfo *mi)
726
{
727
	if (!mi->inbody_header_accum.len)
728
		return;
729
	if (!check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0))
730
		BUG("inbody_header_accum, if not empty, must always contain a valid in-body header");
731
	strbuf_reset(&mi->inbody_header_accum);
732
}
733

734
static int check_inbody_header(struct mailinfo *mi, const struct strbuf *line)
735
{
736
	if (mi->inbody_header_accum.len &&
737
	    (line->buf[0] == ' ' || line->buf[0] == '\t')) {
738
		if (mi->use_scissors && is_scissors_line(line->buf)) {
739
			/*
740
			 * This is a scissors line; do not consider this line
741
			 * as a header continuation line.
742
			 */
743
			flush_inbody_header_accum(mi);
744
			return 0;
745
		}
746
		strbuf_strip_suffix(&mi->inbody_header_accum, "\n");
747
		strbuf_addbuf(&mi->inbody_header_accum, line);
748
		return 1;
749
	}
750

751
	flush_inbody_header_accum(mi);
752

753
	if (starts_with(line->buf, ">From") && isspace(line->buf[5]))
754
		return is_format_patch_separator(line->buf + 1, line->len - 1);
755
	if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
756
		int i;
757
		for (i = 0; header[i]; i++)
758
			if (!strcmp("Subject", header[i])) {
759
				handle_header(&mi->s_hdr_data[i], line);
760
				return 1;
761
			}
762
		return 0;
763
	}
764
	if (is_inbody_header(mi, line)) {
765
		strbuf_addbuf(&mi->inbody_header_accum, line);
766
		return 1;
767
	}
768
	return 0;
769
}
770

771
static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
772
{
773
	assert(!mi->filter_stage);
774

775
	if (mi->header_stage) {
776
		if (!line->len || (line->len == 1 && line->buf[0] == '\n')) {
777
			if (mi->inbody_header_accum.len) {
778
				flush_inbody_header_accum(mi);
779
				mi->header_stage = 0;
780
			}
781
			return 0;
782
		}
783
	}
784

785
	if (mi->use_inbody_headers && mi->header_stage) {
786
		mi->header_stage = check_inbody_header(mi, line);
787
		if (mi->header_stage)
788
			return 0;
789
	} else
790
		/* Only trim the first (blank) line of the commit message
791
		 * when ignoring in-body headers.
792
		 */
793
		mi->header_stage = 0;
794

795
	/* normalize the log message to UTF-8. */
796
	if (convert_to_utf8(mi, line, mi->charset.buf))
797
		return 0; /* mi->input_error already set */
798

799
	if (mi->use_scissors && is_scissors_line(line->buf)) {
800
		int i;
801

802
		strbuf_setlen(&mi->log_message, 0);
803
		mi->header_stage = 1;
804

805
		/*
806
		 * We may have already read "secondary headers"; purge
807
		 * them to give ourselves a clean restart.
808
		 */
809
		for (i = 0; header[i]; i++) {
810
			if (mi->s_hdr_data[i])
811
				strbuf_release(mi->s_hdr_data[i]);
812
			mi->s_hdr_data[i] = NULL;
813
		}
814
		return 0;
815
	}
816

817
	if (patchbreak(line)) {
818
		if (mi->message_id)
819
			strbuf_addf(&mi->log_message,
820
				    "Message-Id: %s\n", mi->message_id);
821
		return 1;
822
	}
823

824
	strbuf_addbuf(&mi->log_message, line);
825
	return 0;
826
}
827

828
static void handle_patch(struct mailinfo *mi, const struct strbuf *line)
829
{
830
	fwrite(line->buf, 1, line->len, mi->patchfile);
831
	mi->patch_lines++;
832
}
833

834
static void handle_filter(struct mailinfo *mi, struct strbuf *line)
835
{
836
	switch (mi->filter_stage) {
837
	case 0:
838
		if (!handle_commit_msg(mi, line))
839
			break;
840
		mi->filter_stage++;
841
		/* fallthrough */
842
	case 1:
843
		handle_patch(mi, line);
844
		break;
845
	}
846
}
847

848
static int is_rfc2822_header(const struct strbuf *line)
849
{
850
	/*
851
	 * The section that defines the loosest possible
852
	 * field name is "3.6.8 Optional fields".
853
	 *
854
	 * optional-field = field-name ":" unstructured CRLF
855
	 * field-name = 1*ftext
856
	 * ftext = %d33-57 / %59-126
857
	 */
858
	int ch;
859
	char *cp = line->buf;
860

861
	/* Count mbox From headers as headers */
862
	if (starts_with(cp, "From ") || starts_with(cp, ">From "))
863
		return 1;
864

865
	while ((ch = *cp++)) {
866
		if (ch == ':')
867
			return 1;
868
		if ((33 <= ch && ch <= 57) ||
869
		    (59 <= ch && ch <= 126))
870
			continue;
871
		break;
872
	}
873
	return 0;
874
}
875

876
static int read_one_header_line(struct strbuf *line, FILE *in)
877
{
878
	struct strbuf continuation = STRBUF_INIT;
879

880
	/* Get the first part of the line. */
881
	if (strbuf_getline_lf(line, in))
882
		return 0;
883

884
	/*
885
	 * Is it an empty line or not a valid rfc2822 header?
886
	 * If so, stop here, and return false ("not a header")
887
	 */
888
	strbuf_rtrim(line);
889
	if (!line->len || !is_rfc2822_header(line)) {
890
		/* Re-add the newline */
891
		strbuf_addch(line, '\n');
892
		return 0;
893
	}
894

895
	/*
896
	 * Now we need to eat all the continuation lines..
897
	 * Yuck, 2822 header "folding"
898
	 */
899
	for (;;) {
900
		int peek;
901

902
		peek = fgetc(in);
903
		if (peek == EOF)
904
			break;
905
		ungetc(peek, in);
906
		if (peek != ' ' && peek != '\t')
907
			break;
908
		if (strbuf_getline_lf(&continuation, in))
909
			break;
910
		continuation.buf[0] = ' ';
911
		strbuf_rtrim(&continuation);
912
		strbuf_addbuf(line, &continuation);
913
	}
914
	strbuf_release(&continuation);
915

916
	return 1;
917
}
918

919
static int find_boundary(struct mailinfo *mi, struct strbuf *line)
920
{
921
	while (!strbuf_getline_lf(line, mi->input)) {
922
		if (*(mi->content_top) && is_multipart_boundary(mi, line))
923
			return 1;
924
	}
925
	return 0;
926
}
927

928
static int handle_boundary(struct mailinfo *mi, struct strbuf *line)
929
{
930
	struct strbuf newline = STRBUF_INIT;
931

932
	strbuf_addch(&newline, '\n');
933
again:
934
	if (line->len >= (*(mi->content_top))->len + 2 &&
935
	    !memcmp(line->buf + (*(mi->content_top))->len, "--", 2)) {
936
		/* we hit an end boundary */
937
		/* pop the current boundary off the stack */
938
		strbuf_release(*(mi->content_top));
939
		FREE_AND_NULL(*(mi->content_top));
940

941
		/* technically won't happen as is_multipart_boundary()
942
		   will fail first.  But just in case..
943
		 */
944
		if (--mi->content_top < mi->content) {
945
			error("Detected mismatched boundaries, can't recover");
946
			mi->input_error = -1;
947
			mi->content_top = mi->content;
948
			strbuf_release(&newline);
949
			return 0;
950
		}
951
		handle_filter(mi, &newline);
952
		strbuf_release(&newline);
953
		if (mi->input_error)
954
			return 0;
955

956
		/* skip to the next boundary */
957
		if (!find_boundary(mi, line))
958
			return 0;
959
		goto again;
960
	}
961

962
	/* set some defaults */
963
	mi->transfer_encoding = TE_DONTCARE;
964
	strbuf_reset(&mi->charset);
965

966
	/* slurp in this section's info */
967
	while (read_one_header_line(line, mi->input))
968
		check_header(mi, line, mi->p_hdr_data, 0);
969

970
	strbuf_release(&newline);
971
	/* replenish line */
972
	if (strbuf_getline_lf(line, mi->input))
973
		return 0;
974
	strbuf_addch(line, '\n');
975
	return 1;
976
}
977

978
static void handle_filter_flowed(struct mailinfo *mi, struct strbuf *line,
979
				 struct strbuf *prev)
980
{
981
	size_t len = line->len;
982
	const char *rest;
983

984
	if (!mi->format_flowed) {
985
		handle_filter(mi, line);
986
		return;
987
	}
988

989
	if (line->buf[len - 1] == '\n') {
990
		len--;
991
		if (len && line->buf[len - 1] == '\r')
992
			len--;
993
	}
994

995
	/* Keep signature separator as-is. */
996
	if (skip_prefix(line->buf, "-- ", &rest) && rest - line->buf == len) {
997
		if (prev->len) {
998
			handle_filter(mi, prev);
999
			strbuf_reset(prev);
1000
		}
1001
		handle_filter(mi, line);
1002
		return;
1003
	}
1004

1005
	/* Unstuff space-stuffed line. */
1006
	if (len && line->buf[0] == ' ') {
1007
		strbuf_remove(line, 0, 1);
1008
		len--;
1009
	}
1010

1011
	/* Save flowed line for later, but without the soft line break. */
1012
	if (len && line->buf[len - 1] == ' ') {
1013
		strbuf_add(prev, line->buf, len - !!mi->delsp);
1014
		return;
1015
	}
1016

1017
	/* Prepend any previous partial lines */
1018
	strbuf_insert(line, 0, prev->buf, prev->len);
1019
	strbuf_reset(prev);
1020

1021
	handle_filter(mi, line);
1022
}
1023

1024
static void handle_body(struct mailinfo *mi, struct strbuf *line)
1025
{
1026
	struct strbuf prev = STRBUF_INIT;
1027

1028
	/* Skip up to the first boundary */
1029
	if (*(mi->content_top)) {
1030
		if (!find_boundary(mi, line))
1031
			goto handle_body_out;
1032
	}
1033

1034
	do {
1035
		/* process any boundary lines */
1036
		if (*(mi->content_top) && is_multipart_boundary(mi, line)) {
1037
			/* flush any leftover */
1038
			if (prev.len) {
1039
				handle_filter(mi, &prev);
1040
				strbuf_reset(&prev);
1041
			}
1042
			if (!handle_boundary(mi, line))
1043
				goto handle_body_out;
1044
		}
1045

1046
		/* Unwrap transfer encoding */
1047
		decode_transfer_encoding(mi, line);
1048

1049
		switch (mi->transfer_encoding) {
1050
		case TE_BASE64:
1051
		case TE_QP:
1052
		{
1053
			struct strbuf **lines, **it, *sb;
1054

1055
			/* Prepend any previous partial lines */
1056
			strbuf_insert(line, 0, prev.buf, prev.len);
1057
			strbuf_reset(&prev);
1058

1059
			/*
1060
			 * This is a decoded line that may contain
1061
			 * multiple new lines.  Pass only one chunk
1062
			 * at a time to handle_filter()
1063
			 */
1064
			lines = strbuf_split(line, '\n');
1065
			for (it = lines; (sb = *it); it++) {
1066
				if (*(it + 1) == NULL) /* The last line */
1067
					if (sb->buf[sb->len - 1] != '\n') {
1068
						/* Partial line, save it for later. */
1069
						strbuf_addbuf(&prev, sb);
1070
						break;
1071
					}
1072
				handle_filter_flowed(mi, sb, &prev);
1073
			}
1074
			/*
1075
			 * The partial chunk is saved in "prev" and will be
1076
			 * appended by the next iteration of read_line_with_nul().
1077
			 */
1078
			strbuf_list_free(lines);
1079
			break;
1080
		}
1081
		default:
1082
			handle_filter_flowed(mi, line, &prev);
1083
		}
1084

1085
		if (mi->input_error)
1086
			break;
1087
	} while (!strbuf_getwholeline(line, mi->input, '\n'));
1088

1089
	if (prev.len)
1090
		handle_filter(mi, &prev);
1091

1092
	flush_inbody_header_accum(mi);
1093

1094
handle_body_out:
1095
	strbuf_release(&prev);
1096
}
1097

1098
static void output_header_lines(FILE *fout, const char *hdr, const struct strbuf *data)
1099
{
1100
	const char *sp = data->buf;
1101
	while (1) {
1102
		char *ep = strchr(sp, '\n');
1103
		int len;
1104
		if (!ep)
1105
			len = strlen(sp);
1106
		else
1107
			len = ep - sp;
1108
		fprintf(fout, "%s: %.*s\n", hdr, len, sp);
1109
		if (!ep)
1110
			break;
1111
		sp = ep + 1;
1112
	}
1113
}
1114

1115
static void handle_info(struct mailinfo *mi)
1116
{
1117
	struct strbuf *hdr;
1118
	int i;
1119

1120
	for (i = 0; header[i]; i++) {
1121
		/* only print inbody headers if we output a patch file */
1122
		if (mi->patch_lines && mi->s_hdr_data[i])
1123
			hdr = mi->s_hdr_data[i];
1124
		else if (mi->p_hdr_data[i])
1125
			hdr = mi->p_hdr_data[i];
1126
		else
1127
			continue;
1128

1129
		if (!strcmp(header[i], "Subject")) {
1130
			if (!mi->keep_subject) {
1131
				cleanup_subject(mi, hdr);
1132
				cleanup_space(hdr);
1133
			}
1134
			output_header_lines(mi->output, "Subject", hdr);
1135
		} else if (!strcmp(header[i], "From")) {
1136
			cleanup_space(hdr);
1137
			handle_from(mi, hdr);
1138
			fprintf(mi->output, "Author: %s\n", mi->name.buf);
1139
			fprintf(mi->output, "Email: %s\n", mi->email.buf);
1140
		} else {
1141
			cleanup_space(hdr);
1142
			fprintf(mi->output, "%s: %s\n", header[i], hdr->buf);
1143
		}
1144
	}
1145
	fprintf(mi->output, "\n");
1146
}
1147

1148
int mailinfo(struct mailinfo *mi, const char *msg, const char *patch)
1149
{
1150
	FILE *cmitmsg;
1151
	int peek;
1152
	struct strbuf line = STRBUF_INIT;
1153

1154
	cmitmsg = fopen(msg, "w");
1155
	if (!cmitmsg) {
1156
		perror(msg);
1157
		return -1;
1158
	}
1159
	mi->patchfile = fopen(patch, "w");
1160
	if (!mi->patchfile) {
1161
		perror(patch);
1162
		fclose(cmitmsg);
1163
		return -1;
1164
	}
1165

1166
	mi->p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->p_hdr_data)));
1167
	mi->s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->s_hdr_data)));
1168

1169
	do {
1170
		peek = fgetc(mi->input);
1171
		if (peek == EOF) {
1172
			fclose(cmitmsg);
1173
			return error("empty patch: '%s'", patch);
1174
		}
1175
	} while (isspace(peek));
1176
	ungetc(peek, mi->input);
1177

1178
	/* process the email header */
1179
	while (read_one_header_line(&line, mi->input))
1180
		check_header(mi, &line, mi->p_hdr_data, 1);
1181

1182
	handle_body(mi, &line);
1183
	fwrite(mi->log_message.buf, 1, mi->log_message.len, cmitmsg);
1184
	fclose(cmitmsg);
1185
	fclose(mi->patchfile);
1186

1187
	handle_info(mi);
1188
	strbuf_release(&line);
1189
	return mi->input_error;
1190
}
1191

1192
static int git_mailinfo_config(const char *var, const char *value, void *mi_)
1193
{
1194
	struct mailinfo *mi = mi_;
1195

1196
	if (!starts_with(var, "mailinfo."))
1197
		return git_default_config(var, value, NULL);
1198
	if (!strcmp(var, "mailinfo.scissors")) {
1199
		mi->use_scissors = git_config_bool(var, value);
1200
		return 0;
1201
	}
1202
	/* perhaps others here */
1203
	return 0;
1204
}
1205

1206
void setup_mailinfo(struct mailinfo *mi)
1207
{
1208
	memset(mi, 0, sizeof(*mi));
1209
	strbuf_init(&mi->name, 0);
1210
	strbuf_init(&mi->email, 0);
1211
	strbuf_init(&mi->charset, 0);
1212
	strbuf_init(&mi->log_message, 0);
1213
	strbuf_init(&mi->inbody_header_accum, 0);
1214
	mi->header_stage = 1;
1215
	mi->use_inbody_headers = 1;
1216
	mi->content_top = mi->content;
1217
	git_config(git_mailinfo_config, mi);
1218
}
1219

1220
void clear_mailinfo(struct mailinfo *mi)
1221
{
1222
	int i;
1223

1224
	strbuf_release(&mi->name);
1225
	strbuf_release(&mi->email);
1226
	strbuf_release(&mi->charset);
1227
	strbuf_release(&mi->inbody_header_accum);
1228
	free(mi->message_id);
1229

1230
	if (mi->p_hdr_data)
1231
		for (i = 0; mi->p_hdr_data[i]; i++)
1232
			strbuf_release(mi->p_hdr_data[i]);
1233
	free(mi->p_hdr_data);
1234
	if (mi->s_hdr_data)
1235
		for (i = 0; mi->s_hdr_data[i]; i++)
1236
			strbuf_release(mi->s_hdr_data[i]);
1237
	free(mi->s_hdr_data);
1238

1239
	while (mi->content < mi->content_top) {
1240
		free(*(mi->content_top));
1241
		mi->content_top--;
1242
	}
1243

1244
	strbuf_release(&mi->log_message);
1245
}
1246