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 void handle_content_type(struct mailinfo *mi, struct strbuf *line)
241
{
242
	struct strbuf *boundary = xmalloc(sizeof(struct strbuf));
243
	strbuf_init(boundary, line->len);
244

245
	if (slurp_attr(line->buf, "boundary=", boundary)) {
246
		strbuf_insert(boundary, 0, "--", 2);
247
		if (++mi->content_top >= &mi->content[MAX_BOUNDARIES]) {
248
			error("Too many boundaries to handle");
249
			mi->input_error = -1;
250
			mi->content_top = &mi->content[MAX_BOUNDARIES] - 1;
251
			return;
252
		}
253
		*(mi->content_top) = boundary;
254
		boundary = NULL;
255
	}
256
	slurp_attr(line->buf, "charset=", &mi->charset);
257

258
	if (boundary) {
259
		strbuf_release(boundary);
260
		free(boundary);
261
	}
262
}
263

264
static void handle_content_transfer_encoding(struct mailinfo *mi,
265
					     const struct strbuf *line)
266
{
267
	if (strcasestr(line->buf, "base64"))
268
		mi->transfer_encoding = TE_BASE64;
269
	else if (strcasestr(line->buf, "quoted-printable"))
270
		mi->transfer_encoding = TE_QP;
271
	else
272
		mi->transfer_encoding = TE_DONTCARE;
273
}
274

275
static int is_multipart_boundary(struct mailinfo *mi, const struct strbuf *line)
276
{
277
	struct strbuf *content_top = *(mi->content_top);
278

279
	return ((content_top->len <= line->len) &&
280
		!memcmp(line->buf, content_top->buf, content_top->len));
281
}
282

283
static void cleanup_subject(struct mailinfo *mi, struct strbuf *subject)
284
{
285
	size_t at = 0;
286

287
	while (at < subject->len) {
288
		char *pos;
289
		size_t remove;
290

291
		switch (subject->buf[at]) {
292
		case 'r': case 'R':
293
			if (subject->len <= at + 3)
294
				break;
295
			if ((subject->buf[at + 1] == 'e' ||
296
			     subject->buf[at + 1] == 'E') &&
297
			    subject->buf[at + 2] == ':') {
298
				strbuf_remove(subject, at, 3);
299
				continue;
300
			}
301
			at++;
302
			break;
303
		case ' ': case '\t': case ':':
304
			strbuf_remove(subject, at, 1);
305
			continue;
306
		case '[':
307
			pos = strchr(subject->buf + at, ']');
308
			if (!pos)
309
				break;
310
			remove = pos - subject->buf + at + 1;
311
			if (!mi->keep_non_patch_brackets_in_subject ||
312
			    (7 <= remove &&
313
			     memmem(subject->buf + at, remove, "PATCH", 5)))
314
				strbuf_remove(subject, at, remove);
315
			else {
316
				at += remove;
317
				/*
318
				 * If the input had a space after the ], keep
319
				 * it.  We don't bother with finding the end of
320
				 * the space, since we later normalize it
321
				 * anyway.
322
				 */
323
				if (isspace(subject->buf[at]))
324
					at += 1;
325
			}
326
			continue;
327
		}
328
		break;
329
	}
330
	strbuf_trim(subject);
331
}
332

333
#define MAX_HDR_PARSED 10
334
static const char *header[MAX_HDR_PARSED] = {
335
	"From","Subject","Date",
336
};
337

338
static inline int cmp_header(const struct strbuf *line, const char *hdr)
339
{
340
	int len = strlen(hdr);
341
	return !strncasecmp(line->buf, hdr, len) && line->len > len &&
342
			line->buf[len] == ':' && isspace(line->buf[len + 1]);
343
}
344

345
static int is_format_patch_separator(const char *line, int len)
346
{
347
	static const char SAMPLE[] =
348
		"From e6807f3efca28b30decfecb1732a56c7db1137ee Mon Sep 17 00:00:00 2001\n";
349
	const char *cp;
350

351
	if (len != strlen(SAMPLE))
352
		return 0;
353
	if (!skip_prefix(line, "From ", &cp))
354
		return 0;
355
	if (strspn(cp, "0123456789abcdef") != 40)
356
		return 0;
357
	cp += 40;
358
	return !memcmp(SAMPLE + (cp - line), cp, strlen(SAMPLE) - (cp - line));
359
}
360

361
static struct strbuf *decode_q_segment(const struct strbuf *q_seg, int rfc2047)
362
{
363
	const char *in = q_seg->buf;
364
	int c;
365
	struct strbuf *out = xmalloc(sizeof(struct strbuf));
366
	strbuf_init(out, q_seg->len);
367

368
	while ((c = *in++) != 0) {
369
		if (c == '=') {
370
			int ch, d = *in;
371
			if (d == '\n' || !d)
372
				break; /* drop trailing newline */
373
			ch = hex2chr(in);
374
			if (ch >= 0) {
375
				strbuf_addch(out, ch);
376
				in += 2;
377
				continue;
378
			}
379
			/* garbage -- fall through */
380
		}
381
		if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
382
			c = 0x20;
383
		strbuf_addch(out, c);
384
	}
385
	return out;
386
}
387

388
static struct strbuf *decode_b_segment(const struct strbuf *b_seg)
389
{
390
	/* Decode in..ep, possibly in-place to ot */
391
	int c, pos = 0, acc = 0;
392
	const char *in = b_seg->buf;
393
	struct strbuf *out = xmalloc(sizeof(struct strbuf));
394
	strbuf_init(out, b_seg->len);
395

396
	while ((c = *in++) != 0) {
397
		if (c == '+')
398
			c = 62;
399
		else if (c == '/')
400
			c = 63;
401
		else if ('A' <= c && c <= 'Z')
402
			c -= 'A';
403
		else if ('a' <= c && c <= 'z')
404
			c -= 'a' - 26;
405
		else if ('0' <= c && c <= '9')
406
			c -= '0' - 52;
407
		else
408
			continue; /* garbage */
409
		switch (pos++) {
410
		case 0:
411
			acc = (c << 2);
412
			break;
413
		case 1:
414
			strbuf_addch(out, (acc | (c >> 4)));
415
			acc = (c & 15) << 4;
416
			break;
417
		case 2:
418
			strbuf_addch(out, (acc | (c >> 2)));
419
			acc = (c & 3) << 6;
420
			break;
421
		case 3:
422
			strbuf_addch(out, (acc | c));
423
			acc = pos = 0;
424
			break;
425
		}
426
	}
427
	return out;
428
}
429

430
static int convert_to_utf8(struct mailinfo *mi,
431
			   struct strbuf *line, const char *charset)
432
{
433
	char *out;
434

435
	if (!mi->metainfo_charset || !charset || !*charset)
436
		return 0;
437

438
	if (same_encoding(mi->metainfo_charset, charset))
439
		return 0;
440
	out = reencode_string(line->buf, mi->metainfo_charset, charset);
441
	if (!out) {
442
		mi->input_error = -1;
443
		return error("cannot convert from %s to %s",
444
			     charset, mi->metainfo_charset);
445
	}
446
	strbuf_attach(line, out, strlen(out), strlen(out));
447
	return 0;
448
}
449

450
static void decode_header(struct mailinfo *mi, struct strbuf *it)
451
{
452
	char *in, *ep, *cp;
453
	struct strbuf outbuf = STRBUF_INIT, *dec;
454
	struct strbuf charset_q = STRBUF_INIT, piecebuf = STRBUF_INIT;
455
	int found_error = 1; /* pessimism */
456

457
	in = it->buf;
458
	while (in - it->buf <= it->len && (ep = strstr(in, "=?")) != NULL) {
459
		int encoding;
460
		strbuf_reset(&charset_q);
461
		strbuf_reset(&piecebuf);
462

463
		if (in != ep) {
464
			/*
465
			 * We are about to process an encoded-word
466
			 * that begins at ep, but there is something
467
			 * before the encoded word.
468
			 */
469
			char *scan;
470
			for (scan = in; scan < ep; scan++)
471
				if (!isspace(*scan))
472
					break;
473

474
			if (scan != ep || in == it->buf) {
475
				/*
476
				 * We should not lose that "something",
477
				 * unless we have just processed an
478
				 * encoded-word, and there is only LWS
479
				 * before the one we are about to process.
480
				 */
481
				strbuf_add(&outbuf, in, ep - in);
482
			}
483
		}
484
		/* E.g.
485
		 * ep : "=?iso-2022-jp?B?GyR...?= foo"
486
		 * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
487
		 */
488
		ep += 2;
489

490
		if (ep - it->buf >= it->len || !(cp = strchr(ep, '?')))
491
			goto release_return;
492

493
		if (cp + 3 - it->buf > it->len)
494
			goto release_return;
495
		strbuf_add(&charset_q, ep, cp - ep);
496

497
		encoding = cp[1];
498
		if (!encoding || cp[2] != '?')
499
			goto release_return;
500
		ep = strstr(cp + 3, "?=");
501
		if (!ep)
502
			goto release_return;
503
		strbuf_add(&piecebuf, cp + 3, ep - cp - 3);
504
		switch (tolower(encoding)) {
505
		default:
506
			goto release_return;
507
		case 'b':
508
			dec = decode_b_segment(&piecebuf);
509
			break;
510
		case 'q':
511
			dec = decode_q_segment(&piecebuf, 1);
512
			break;
513
		}
514
		if (convert_to_utf8(mi, dec, charset_q.buf))
515
			goto release_return;
516

517
		strbuf_addbuf(&outbuf, dec);
518
		strbuf_release(dec);
519
		free(dec);
520
		in = ep + 2;
521
	}
522
	strbuf_addstr(&outbuf, in);
523
	strbuf_reset(it);
524
	strbuf_addbuf(it, &outbuf);
525
	found_error = 0;
526
release_return:
527
	strbuf_release(&outbuf);
528
	strbuf_release(&charset_q);
529
	strbuf_release(&piecebuf);
530

531
	if (found_error)
532
		mi->input_error = -1;
533
}
534

535
static int check_header(struct mailinfo *mi,
536
			const struct strbuf *line,
537
			struct strbuf *hdr_data[], int overwrite)
538
{
539
	int i, ret = 0, len;
540
	struct strbuf sb = STRBUF_INIT;
541

542
	/* search for the interesting parts */
543
	for (i = 0; header[i]; i++) {
544
		int len = strlen(header[i]);
545
		if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) {
546
			/* Unwrap inline B and Q encoding, and optionally
547
			 * normalize the meta information to utf8.
548
			 */
549
			strbuf_add(&sb, line->buf + len + 2, line->len - len - 2);
550
			decode_header(mi, &sb);
551
			handle_header(&hdr_data[i], &sb);
552
			ret = 1;
553
			goto check_header_out;
554
		}
555
	}
556

557
	/* Content stuff */
558
	if (cmp_header(line, "Content-Type")) {
559
		len = strlen("Content-Type: ");
560
		strbuf_add(&sb, line->buf + len, line->len - len);
561
		decode_header(mi, &sb);
562
		strbuf_insert(&sb, 0, "Content-Type: ", len);
563
		handle_content_type(mi, &sb);
564
		ret = 1;
565
		goto check_header_out;
566
	}
567
	if (cmp_header(line, "Content-Transfer-Encoding")) {
568
		len = strlen("Content-Transfer-Encoding: ");
569
		strbuf_add(&sb, line->buf + len, line->len - len);
570
		decode_header(mi, &sb);
571
		handle_content_transfer_encoding(mi, &sb);
572
		ret = 1;
573
		goto check_header_out;
574
	}
575
	if (cmp_header(line, "Message-Id")) {
576
		len = strlen("Message-Id: ");
577
		strbuf_add(&sb, line->buf + len, line->len - len);
578
		decode_header(mi, &sb);
579
		if (mi->add_message_id)
580
			mi->message_id = strbuf_detach(&sb, NULL);
581
		ret = 1;
582
		goto check_header_out;
583
	}
584

585
check_header_out:
586
	strbuf_release(&sb);
587
	return ret;
588
}
589

590
/*
591
 * Returns 1 if the given line or any line beginning with the given line is an
592
 * in-body header (that is, check_header will succeed when passed
593
 * mi->s_hdr_data).
594
 */
595
static int is_inbody_header(const struct mailinfo *mi,
596
			    const struct strbuf *line)
597
{
598
	int i;
599
	for (i = 0; header[i]; i++)
600
		if (!mi->s_hdr_data[i] && cmp_header(line, header[i]))
601
			return 1;
602
	return 0;
603
}
604

605
static void decode_transfer_encoding(struct mailinfo *mi, struct strbuf *line)
606
{
607
	struct strbuf *ret;
608

609
	switch (mi->transfer_encoding) {
610
	case TE_QP:
611
		ret = decode_q_segment(line, 0);
612
		break;
613
	case TE_BASE64:
614
		ret = decode_b_segment(line);
615
		break;
616
	case TE_DONTCARE:
617
	default:
618
		return;
619
	}
620
	strbuf_reset(line);
621
	strbuf_addbuf(line, ret);
622
	strbuf_release(ret);
623
	free(ret);
624
}
625

626
static inline int patchbreak(const struct strbuf *line)
627
{
628
	size_t i;
629

630
	/* Beginning of a "diff -" header? */
631
	if (starts_with(line->buf, "diff -"))
632
		return 1;
633

634
	/* CVS "Index: " line? */
635
	if (starts_with(line->buf, "Index: "))
636
		return 1;
637

638
	/*
639
	 * "--- <filename>" starts patches without headers
640
	 * "---<sp>*" is a manual separator
641
	 */
642
	if (line->len < 4)
643
		return 0;
644

645
	if (starts_with(line->buf, "---")) {
646
		/* space followed by a filename? */
647
		if (line->buf[3] == ' ' && !isspace(line->buf[4]))
648
			return 1;
649
		/* Just whitespace? */
650
		for (i = 3; i < line->len; i++) {
651
			unsigned char c = line->buf[i];
652
			if (c == '\n')
653
				return 1;
654
			if (!isspace(c))
655
				break;
656
		}
657
		return 0;
658
	}
659
	return 0;
660
}
661

662
static int is_scissors_line(const char *line)
663
{
664
	const char *c;
665
	int scissors = 0, gap = 0;
666
	const char *first_nonblank = NULL, *last_nonblank = NULL;
667
	int visible, perforation = 0, in_perforation = 0;
668

669
	for (c = line; *c; c++) {
670
		if (isspace(*c)) {
671
			if (in_perforation) {
672
				perforation++;
673
				gap++;
674
			}
675
			continue;
676
		}
677
		last_nonblank = c;
678
		if (first_nonblank == NULL)
679
			first_nonblank = c;
680
		if (*c == '-') {
681
			in_perforation = 1;
682
			perforation++;
683
			continue;
684
		}
685
		if ((!memcmp(c, ">8", 2) || !memcmp(c, "8<", 2) ||
686
		     !memcmp(c, ">%", 2) || !memcmp(c, "%<", 2))) {
687
			in_perforation = 1;
688
			perforation += 2;
689
			scissors += 2;
690
			c++;
691
			continue;
692
		}
693
		in_perforation = 0;
694
	}
695

696
	/*
697
	 * The mark must be at least 8 bytes long (e.g. "-- >8 --").
698
	 * Even though there can be arbitrary cruft on the same line
699
	 * (e.g. "cut here"), in order to avoid misidentification, the
700
	 * perforation must occupy more than a third of the visible
701
	 * width of the line, and dashes and scissors must occupy more
702
	 * than half of the perforation.
703
	 */
704

705
	if (first_nonblank && last_nonblank)
706
		visible = last_nonblank - first_nonblank + 1;
707
	else
708
		visible = 0;
709
	return (scissors && 8 <= visible &&
710
		visible < perforation * 3 &&
711
		gap * 2 < perforation);
712
}
713

714
static void flush_inbody_header_accum(struct mailinfo *mi)
715
{
716
	if (!mi->inbody_header_accum.len)
717
		return;
718
	if (!check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0))
719
		BUG("inbody_header_accum, if not empty, must always contain a valid in-body header");
720
	strbuf_reset(&mi->inbody_header_accum);
721
}
722

723
static int check_inbody_header(struct mailinfo *mi, const struct strbuf *line)
724
{
725
	if (mi->inbody_header_accum.len &&
726
	    (line->buf[0] == ' ' || line->buf[0] == '\t')) {
727
		if (mi->use_scissors && is_scissors_line(line->buf)) {
728
			/*
729
			 * This is a scissors line; do not consider this line
730
			 * as a header continuation line.
731
			 */
732
			flush_inbody_header_accum(mi);
733
			return 0;
734
		}
735
		strbuf_strip_suffix(&mi->inbody_header_accum, "\n");
736
		strbuf_addbuf(&mi->inbody_header_accum, line);
737
		return 1;
738
	}
739

740
	flush_inbody_header_accum(mi);
741

742
	if (starts_with(line->buf, ">From") && isspace(line->buf[5]))
743
		return is_format_patch_separator(line->buf + 1, line->len - 1);
744
	if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
745
		int i;
746
		for (i = 0; header[i]; i++)
747
			if (!strcmp("Subject", header[i])) {
748
				handle_header(&mi->s_hdr_data[i], line);
749
				return 1;
750
			}
751
		return 0;
752
	}
753
	if (is_inbody_header(mi, line)) {
754
		strbuf_addbuf(&mi->inbody_header_accum, line);
755
		return 1;
756
	}
757
	return 0;
758
}
759

760
static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
761
{
762
	assert(!mi->filter_stage);
763

764
	if (mi->header_stage) {
765
		if (!line->len || (line->len == 1 && line->buf[0] == '\n')) {
766
			if (mi->inbody_header_accum.len) {
767
				flush_inbody_header_accum(mi);
768
				mi->header_stage = 0;
769
			}
770
			return 0;
771
		}
772
	}
773

774
	if (mi->use_inbody_headers && mi->header_stage) {
775
		mi->header_stage = check_inbody_header(mi, line);
776
		if (mi->header_stage)
777
			return 0;
778
	} else
779
		/* Only trim the first (blank) line of the commit message
780
		 * when ignoring in-body headers.
781
		 */
782
		mi->header_stage = 0;
783

784
	/* normalize the log message to UTF-8. */
785
	if (convert_to_utf8(mi, line, mi->charset.buf))
786
		return 0; /* mi->input_error already set */
787

788
	if (mi->use_scissors && is_scissors_line(line->buf)) {
789
		int i;
790

791
		strbuf_setlen(&mi->log_message, 0);
792
		mi->header_stage = 1;
793

794
		/*
795
		 * We may have already read "secondary headers"; purge
796
		 * them to give ourselves a clean restart.
797
		 */
798
		for (i = 0; header[i]; i++) {
799
			if (mi->s_hdr_data[i])
800
				strbuf_release(mi->s_hdr_data[i]);
801
			mi->s_hdr_data[i] = NULL;
802
		}
803
		return 0;
804
	}
805

806
	if (patchbreak(line)) {
807
		if (mi->message_id)
808
			strbuf_addf(&mi->log_message,
809
				    "Message-Id: %s\n", mi->message_id);
810
		return 1;
811
	}
812

813
	strbuf_addbuf(&mi->log_message, line);
814
	return 0;
815
}
816

817
static void handle_patch(struct mailinfo *mi, const struct strbuf *line)
818
{
819
	fwrite(line->buf, 1, line->len, mi->patchfile);
820
	mi->patch_lines++;
821
}
822

823
static void handle_filter(struct mailinfo *mi, struct strbuf *line)
824
{
825
	switch (mi->filter_stage) {
826
	case 0:
827
		if (!handle_commit_msg(mi, line))
828
			break;
829
		mi->filter_stage++;
830
		/* fallthrough */
831
	case 1:
832
		handle_patch(mi, line);
833
		break;
834
	}
835
}
836

837
static int is_rfc2822_header(const struct strbuf *line)
838
{
839
	/*
840
	 * The section that defines the loosest possible
841
	 * field name is "3.6.8 Optional fields".
842
	 *
843
	 * optional-field = field-name ":" unstructured CRLF
844
	 * field-name = 1*ftext
845
	 * ftext = %d33-57 / %59-126
846
	 */
847
	int ch;
848
	char *cp = line->buf;
849

850
	/* Count mbox From headers as headers */
851
	if (starts_with(cp, "From ") || starts_with(cp, ">From "))
852
		return 1;
853

854
	while ((ch = *cp++)) {
855
		if (ch == ':')
856
			return 1;
857
		if ((33 <= ch && ch <= 57) ||
858
		    (59 <= ch && ch <= 126))
859
			continue;
860
		break;
861
	}
862
	return 0;
863
}
864

865
static int read_one_header_line(struct strbuf *line, FILE *in)
866
{
867
	struct strbuf continuation = STRBUF_INIT;
868

869
	/* Get the first part of the line. */
870
	if (strbuf_getline_lf(line, in))
871
		return 0;
872

873
	/*
874
	 * Is it an empty line or not a valid rfc2822 header?
875
	 * If so, stop here, and return false ("not a header")
876
	 */
877
	strbuf_rtrim(line);
878
	if (!line->len || !is_rfc2822_header(line)) {
879
		/* Re-add the newline */
880
		strbuf_addch(line, '\n');
881
		return 0;
882
	}
883

884
	/*
885
	 * Now we need to eat all the continuation lines..
886
	 * Yuck, 2822 header "folding"
887
	 */
888
	for (;;) {
889
		int peek;
890

891
		peek = fgetc(in);
892
		if (peek == EOF)
893
			break;
894
		ungetc(peek, in);
895
		if (peek != ' ' && peek != '\t')
896
			break;
897
		if (strbuf_getline_lf(&continuation, in))
898
			break;
899
		continuation.buf[0] = ' ';
900
		strbuf_rtrim(&continuation);
901
		strbuf_addbuf(line, &continuation);
902
	}
903
	strbuf_release(&continuation);
904

905
	return 1;
906
}
907

908
static int find_boundary(struct mailinfo *mi, struct strbuf *line)
909
{
910
	while (!strbuf_getline_lf(line, mi->input)) {
911
		if (*(mi->content_top) && is_multipart_boundary(mi, line))
912
			return 1;
913
	}
914
	return 0;
915
}
916

917
static int handle_boundary(struct mailinfo *mi, struct strbuf *line)
918
{
919
	struct strbuf newline = STRBUF_INIT;
920

921
	strbuf_addch(&newline, '\n');
922
again:
923
	if (line->len >= (*(mi->content_top))->len + 2 &&
924
	    !memcmp(line->buf + (*(mi->content_top))->len, "--", 2)) {
925
		/* we hit an end boundary */
926
		/* pop the current boundary off the stack */
927
		strbuf_release(*(mi->content_top));
928
		FREE_AND_NULL(*(mi->content_top));
929

930
		/* technically won't happen as is_multipart_boundary()
931
		   will fail first.  But just in case..
932
		 */
933
		if (--mi->content_top < mi->content) {
934
			error("Detected mismatched boundaries, can't recover");
935
			mi->input_error = -1;
936
			mi->content_top = mi->content;
937
			strbuf_release(&newline);
938
			return 0;
939
		}
940
		handle_filter(mi, &newline);
941
		strbuf_release(&newline);
942
		if (mi->input_error)
943
			return 0;
944

945
		/* skip to the next boundary */
946
		if (!find_boundary(mi, line))
947
			return 0;
948
		goto again;
949
	}
950

951
	/* set some defaults */
952
	mi->transfer_encoding = TE_DONTCARE;
953
	strbuf_reset(&mi->charset);
954

955
	/* slurp in this section's info */
956
	while (read_one_header_line(line, mi->input))
957
		check_header(mi, line, mi->p_hdr_data, 0);
958

959
	strbuf_release(&newline);
960
	/* replenish line */
961
	if (strbuf_getline_lf(line, mi->input))
962
		return 0;
963
	strbuf_addch(line, '\n');
964
	return 1;
965
}
966

967
static void handle_body(struct mailinfo *mi, struct strbuf *line)
968
{
969
	struct strbuf prev = STRBUF_INIT;
970

971
	/* Skip up to the first boundary */
972
	if (*(mi->content_top)) {
973
		if (!find_boundary(mi, line))
974
			goto handle_body_out;
975
	}
976

977
	do {
978
		/* process any boundary lines */
979
		if (*(mi->content_top) && is_multipart_boundary(mi, line)) {
980
			/* flush any leftover */
981
			if (prev.len) {
982
				handle_filter(mi, &prev);
983
				strbuf_reset(&prev);
984
			}
985
			if (!handle_boundary(mi, line))
986
				goto handle_body_out;
987
		}
988

989
		/* Unwrap transfer encoding */
990
		decode_transfer_encoding(mi, line);
991

992
		switch (mi->transfer_encoding) {
993
		case TE_BASE64:
994
		case TE_QP:
995
		{
996
			struct strbuf **lines, **it, *sb;
997

998
			/* Prepend any previous partial lines */
999
			strbuf_insert(line, 0, prev.buf, prev.len);
1000
			strbuf_reset(&prev);
1001

1002
			/*
1003
			 * This is a decoded line that may contain
1004
			 * multiple new lines.  Pass only one chunk
1005
			 * at a time to handle_filter()
1006
			 */
1007
			lines = strbuf_split(line, '\n');
1008
			for (it = lines; (sb = *it); it++) {
1009
				if (*(it + 1) == NULL) /* The last line */
1010
					if (sb->buf[sb->len - 1] != '\n') {
1011
						/* Partial line, save it for later. */
1012
						strbuf_addbuf(&prev, sb);
1013
						break;
1014
					}
1015
				handle_filter(mi, sb);
1016
			}
1017
			/*
1018
			 * The partial chunk is saved in "prev" and will be
1019
			 * appended by the next iteration of read_line_with_nul().
1020
			 */
1021
			strbuf_list_free(lines);
1022
			break;
1023
		}
1024
		default:
1025
			handle_filter(mi, line);
1026
		}
1027

1028
		if (mi->input_error)
1029
			break;
1030
	} while (!strbuf_getwholeline(line, mi->input, '\n'));
1031

1032
	flush_inbody_header_accum(mi);
1033

1034
handle_body_out:
1035
	strbuf_release(&prev);
1036
}
1037

1038
static void output_header_lines(FILE *fout, const char *hdr, const struct strbuf *data)
1039
{
1040
	const char *sp = data->buf;
1041
	while (1) {
1042
		char *ep = strchr(sp, '\n');
1043
		int len;
1044
		if (!ep)
1045
			len = strlen(sp);
1046
		else
1047
			len = ep - sp;
1048
		fprintf(fout, "%s: %.*s\n", hdr, len, sp);
1049
		if (!ep)
1050
			break;
1051
		sp = ep + 1;
1052
	}
1053
}
1054

1055
static void handle_info(struct mailinfo *mi)
1056
{
1057
	struct strbuf *hdr;
1058
	int i;
1059

1060
	for (i = 0; header[i]; i++) {
1061
		/* only print inbody headers if we output a patch file */
1062
		if (mi->patch_lines && mi->s_hdr_data[i])
1063
			hdr = mi->s_hdr_data[i];
1064
		else if (mi->p_hdr_data[i])
1065
			hdr = mi->p_hdr_data[i];
1066
		else
1067
			continue;
1068

1069
		if (!strcmp(header[i], "Subject")) {
1070
			if (!mi->keep_subject) {
1071
				cleanup_subject(mi, hdr);
1072
				cleanup_space(hdr);
1073
			}
1074
			output_header_lines(mi->output, "Subject", hdr);
1075
		} else if (!strcmp(header[i], "From")) {
1076
			cleanup_space(hdr);
1077
			handle_from(mi, hdr);
1078
			fprintf(mi->output, "Author: %s\n", mi->name.buf);
1079
			fprintf(mi->output, "Email: %s\n", mi->email.buf);
1080
		} else {
1081
			cleanup_space(hdr);
1082
			fprintf(mi->output, "%s: %s\n", header[i], hdr->buf);
1083
		}
1084
	}
1085
	fprintf(mi->output, "\n");
1086
}
1087

1088
int mailinfo(struct mailinfo *mi, const char *msg, const char *patch)
1089
{
1090
	FILE *cmitmsg;
1091
	int peek;
1092
	struct strbuf line = STRBUF_INIT;
1093

1094
	cmitmsg = fopen(msg, "w");
1095
	if (!cmitmsg) {
1096
		perror(msg);
1097
		return -1;
1098
	}
1099
	mi->patchfile = fopen(patch, "w");
1100
	if (!mi->patchfile) {
1101
		perror(patch);
1102
		fclose(cmitmsg);
1103
		return -1;
1104
	}
1105

1106
	mi->p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->p_hdr_data)));
1107
	mi->s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->s_hdr_data)));
1108

1109
	do {
1110
		peek = fgetc(mi->input);
1111
		if (peek == EOF) {
1112
			fclose(cmitmsg);
1113
			return error("empty patch: '%s'", patch);
1114
		}
1115
	} while (isspace(peek));
1116
	ungetc(peek, mi->input);
1117

1118
	/* process the email header */
1119
	while (read_one_header_line(&line, mi->input))
1120
		check_header(mi, &line, mi->p_hdr_data, 1);
1121

1122
	handle_body(mi, &line);
1123
	fwrite(mi->log_message.buf, 1, mi->log_message.len, cmitmsg);
1124
	fclose(cmitmsg);
1125
	fclose(mi->patchfile);
1126

1127
	handle_info(mi);
1128
	strbuf_release(&line);
1129
	return mi->input_error;
1130
}
1131

1132
static int git_mailinfo_config(const char *var, const char *value, void *mi_)
1133
{
1134
	struct mailinfo *mi = mi_;
1135

1136
	if (!starts_with(var, "mailinfo."))
1137
		return git_default_config(var, value, NULL);
1138
	if (!strcmp(var, "mailinfo.scissors")) {
1139
		mi->use_scissors = git_config_bool(var, value);
1140
		return 0;
1141
	}
1142
	/* perhaps others here */
1143
	return 0;
1144
}
1145

1146
void setup_mailinfo(struct mailinfo *mi)
1147
{
1148
	memset(mi, 0, sizeof(*mi));
1149
	strbuf_init(&mi->name, 0);
1150
	strbuf_init(&mi->email, 0);
1151
	strbuf_init(&mi->charset, 0);
1152
	strbuf_init(&mi->log_message, 0);
1153
	strbuf_init(&mi->inbody_header_accum, 0);
1154
	mi->header_stage = 1;
1155
	mi->use_inbody_headers = 1;
1156
	mi->content_top = mi->content;
1157
	git_config(git_mailinfo_config, mi);
1158
}
1159

1160
void clear_mailinfo(struct mailinfo *mi)
1161
{
1162
	int i;
1163

1164
	strbuf_release(&mi->name);
1165
	strbuf_release(&mi->email);
1166
	strbuf_release(&mi->charset);
1167
	strbuf_release(&mi->inbody_header_accum);
1168
	free(mi->message_id);
1169

1170
	if (mi->p_hdr_data)
1171
		for (i = 0; mi->p_hdr_data[i]; i++)
1172
			strbuf_release(mi->p_hdr_data[i]);
1173
	free(mi->p_hdr_data);
1174
	if (mi->s_hdr_data)
1175
		for (i = 0; mi->s_hdr_data[i]; i++)
1176
			strbuf_release(mi->s_hdr_data[i]);
1177
	free(mi->s_hdr_data);
1178

1179
	while (mi->content < mi->content_top) {
1180
		free(*(mi->content_top));
1181
		mi->content_top--;
1182
	}
1183

1184
	strbuf_release(&mi->log_message);
1185
}
1186