strbuf: separate callback for strbuf_expand:ing literals
[git] / pretty.c
1 #include "cache.h"
2 #include "config.h"
3 #include "commit.h"
4 #include "utf8.h"
5 #include "diff.h"
6 #include "revision.h"
7 #include "string-list.h"
8 #include "mailmap.h"
9 #include "log-tree.h"
10 #include "notes.h"
11 #include "color.h"
12 #include "reflog-walk.h"
13 #include "gpg-interface.h"
14 #include "trailer.h"
15
16 static char *user_format;
17 static struct cmt_fmt_map {
18         const char *name;
19         enum cmit_fmt format;
20         int is_tformat;
21         int expand_tabs_in_log;
22         int is_alias;
23         const char *user_format;
24 } *commit_formats;
25 static size_t builtin_formats_len;
26 static size_t commit_formats_len;
27 static size_t commit_formats_alloc;
28 static struct cmt_fmt_map *find_commit_format(const char *sought);
29
30 int commit_format_is_empty(enum cmit_fmt fmt)
31 {
32         return fmt == CMIT_FMT_USERFORMAT && !*user_format;
33 }
34
35 static void save_user_format(struct rev_info *rev, const char *cp, int is_tformat)
36 {
37         free(user_format);
38         user_format = xstrdup(cp);
39         if (is_tformat)
40                 rev->use_terminator = 1;
41         rev->commit_format = CMIT_FMT_USERFORMAT;
42 }
43
44 static int git_pretty_formats_config(const char *var, const char *value, void *cb)
45 {
46         struct cmt_fmt_map *commit_format = NULL;
47         const char *name;
48         const char *fmt;
49         int i;
50
51         if (!skip_prefix(var, "pretty.", &name))
52                 return 0;
53
54         for (i = 0; i < builtin_formats_len; i++) {
55                 if (!strcmp(commit_formats[i].name, name))
56                         return 0;
57         }
58
59         for (i = builtin_formats_len; i < commit_formats_len; i++) {
60                 if (!strcmp(commit_formats[i].name, name)) {
61                         commit_format = &commit_formats[i];
62                         break;
63                 }
64         }
65
66         if (!commit_format) {
67                 ALLOC_GROW(commit_formats, commit_formats_len+1,
68                            commit_formats_alloc);
69                 commit_format = &commit_formats[commit_formats_len];
70                 memset(commit_format, 0, sizeof(*commit_format));
71                 commit_formats_len++;
72         }
73
74         commit_format->name = xstrdup(name);
75         commit_format->format = CMIT_FMT_USERFORMAT;
76         if (git_config_string(&fmt, var, value))
77                 return -1;
78
79         if (skip_prefix(fmt, "format:", &fmt))
80                 commit_format->is_tformat = 0;
81         else if (skip_prefix(fmt, "tformat:", &fmt) || strchr(fmt, '%'))
82                 commit_format->is_tformat = 1;
83         else
84                 commit_format->is_alias = 1;
85         commit_format->user_format = fmt;
86
87         return 0;
88 }
89
90 static void setup_commit_formats(void)
91 {
92         struct cmt_fmt_map builtin_formats[] = {
93                 { "raw",        CMIT_FMT_RAW,           0,      0 },
94                 { "medium",     CMIT_FMT_MEDIUM,        0,      8 },
95                 { "short",      CMIT_FMT_SHORT,         0,      0 },
96                 { "email",      CMIT_FMT_EMAIL,         0,      0 },
97                 { "mboxrd",     CMIT_FMT_MBOXRD,        0,      0 },
98                 { "fuller",     CMIT_FMT_FULLER,        0,      8 },
99                 { "full",       CMIT_FMT_FULL,          0,      8 },
100                 { "oneline",    CMIT_FMT_ONELINE,       1,      0 }
101         };
102         commit_formats_len = ARRAY_SIZE(builtin_formats);
103         builtin_formats_len = commit_formats_len;
104         ALLOC_GROW(commit_formats, commit_formats_len, commit_formats_alloc);
105         memcpy(commit_formats, builtin_formats,
106                sizeof(*builtin_formats)*ARRAY_SIZE(builtin_formats));
107
108         git_config(git_pretty_formats_config, NULL);
109 }
110
111 static struct cmt_fmt_map *find_commit_format_recursive(const char *sought,
112                                                         const char *original,
113                                                         int num_redirections)
114 {
115         struct cmt_fmt_map *found = NULL;
116         size_t found_match_len = 0;
117         int i;
118
119         if (num_redirections >= commit_formats_len)
120                 die("invalid --pretty format: "
121                     "'%s' references an alias which points to itself",
122                     original);
123
124         for (i = 0; i < commit_formats_len; i++) {
125                 size_t match_len;
126
127                 if (!starts_with(commit_formats[i].name, sought))
128                         continue;
129
130                 match_len = strlen(commit_formats[i].name);
131                 if (found == NULL || found_match_len > match_len) {
132                         found = &commit_formats[i];
133                         found_match_len = match_len;
134                 }
135         }
136
137         if (found && found->is_alias) {
138                 found = find_commit_format_recursive(found->user_format,
139                                                      original,
140                                                      num_redirections+1);
141         }
142
143         return found;
144 }
145
146 static struct cmt_fmt_map *find_commit_format(const char *sought)
147 {
148         if (!commit_formats)
149                 setup_commit_formats();
150
151         return find_commit_format_recursive(sought, sought, 0);
152 }
153
154 void get_commit_format(const char *arg, struct rev_info *rev)
155 {
156         struct cmt_fmt_map *commit_format;
157
158         rev->use_terminator = 0;
159         if (!arg) {
160                 rev->commit_format = CMIT_FMT_DEFAULT;
161                 return;
162         }
163         if (skip_prefix(arg, "format:", &arg)) {
164                 save_user_format(rev, arg, 0);
165                 return;
166         }
167
168         if (!*arg || skip_prefix(arg, "tformat:", &arg) || strchr(arg, '%')) {
169                 save_user_format(rev, arg, 1);
170                 return;
171         }
172
173         commit_format = find_commit_format(arg);
174         if (!commit_format)
175                 die("invalid --pretty format: %s", arg);
176
177         rev->commit_format = commit_format->format;
178         rev->use_terminator = commit_format->is_tformat;
179         rev->expand_tabs_in_log_default = commit_format->expand_tabs_in_log;
180         if (commit_format->format == CMIT_FMT_USERFORMAT) {
181                 save_user_format(rev, commit_format->user_format,
182                                  commit_format->is_tformat);
183         }
184 }
185
186 /*
187  * Generic support for pretty-printing the header
188  */
189 static int get_one_line(const char *msg)
190 {
191         int ret = 0;
192
193         for (;;) {
194                 char c = *msg++;
195                 if (!c)
196                         break;
197                 ret++;
198                 if (c == '\n')
199                         break;
200         }
201         return ret;
202 }
203
204 /* High bit set, or ISO-2022-INT */
205 static int non_ascii(int ch)
206 {
207         return !isascii(ch) || ch == '\033';
208 }
209
210 int has_non_ascii(const char *s)
211 {
212         int ch;
213         if (!s)
214                 return 0;
215         while ((ch = *s++) != '\0') {
216                 if (non_ascii(ch))
217                         return 1;
218         }
219         return 0;
220 }
221
222 static int is_rfc822_special(char ch)
223 {
224         switch (ch) {
225         case '(':
226         case ')':
227         case '<':
228         case '>':
229         case '[':
230         case ']':
231         case ':':
232         case ';':
233         case '@':
234         case ',':
235         case '.':
236         case '"':
237         case '\\':
238                 return 1;
239         default:
240                 return 0;
241         }
242 }
243
244 static int needs_rfc822_quoting(const char *s, int len)
245 {
246         int i;
247         for (i = 0; i < len; i++)
248                 if (is_rfc822_special(s[i]))
249                         return 1;
250         return 0;
251 }
252
253 static int last_line_length(struct strbuf *sb)
254 {
255         int i;
256
257         /* How many bytes are already used on the last line? */
258         for (i = sb->len - 1; i >= 0; i--)
259                 if (sb->buf[i] == '\n')
260                         break;
261         return sb->len - (i + 1);
262 }
263
264 static void add_rfc822_quoted(struct strbuf *out, const char *s, int len)
265 {
266         int i;
267
268         /* just a guess, we may have to also backslash-quote */
269         strbuf_grow(out, len + 2);
270
271         strbuf_addch(out, '"');
272         for (i = 0; i < len; i++) {
273                 switch (s[i]) {
274                 case '"':
275                 case '\\':
276                         strbuf_addch(out, '\\');
277                         /* fall through */
278                 default:
279                         strbuf_addch(out, s[i]);
280                 }
281         }
282         strbuf_addch(out, '"');
283 }
284
285 enum rfc2047_type {
286         RFC2047_SUBJECT,
287         RFC2047_ADDRESS
288 };
289
290 static int is_rfc2047_special(char ch, enum rfc2047_type type)
291 {
292         /*
293          * rfc2047, section 4.2:
294          *
295          *    8-bit values which correspond to printable ASCII characters other
296          *    than "=", "?", and "_" (underscore), MAY be represented as those
297          *    characters.  (But see section 5 for restrictions.)  In
298          *    particular, SPACE and TAB MUST NOT be represented as themselves
299          *    within encoded words.
300          */
301
302         /*
303          * rule out non-ASCII characters and non-printable characters (the
304          * non-ASCII check should be redundant as isprint() is not localized
305          * and only knows about ASCII, but be defensive about that)
306          */
307         if (non_ascii(ch) || !isprint(ch))
308                 return 1;
309
310         /*
311          * rule out special printable characters (' ' should be the only
312          * whitespace character considered printable, but be defensive and use
313          * isspace())
314          */
315         if (isspace(ch) || ch == '=' || ch == '?' || ch == '_')
316                 return 1;
317
318         /*
319          * rfc2047, section 5.3:
320          *
321          *    As a replacement for a 'word' entity within a 'phrase', for example,
322          *    one that precedes an address in a From, To, or Cc header.  The ABNF
323          *    definition for 'phrase' from RFC 822 thus becomes:
324          *
325          *    phrase = 1*( encoded-word / word )
326          *
327          *    In this case the set of characters that may be used in a "Q"-encoded
328          *    'encoded-word' is restricted to: <upper and lower case ASCII
329          *    letters, decimal digits, "!", "*", "+", "-", "/", "=", and "_"
330          *    (underscore, ASCII 95.)>.  An 'encoded-word' that appears within a
331          *    'phrase' MUST be separated from any adjacent 'word', 'text' or
332          *    'special' by 'linear-white-space'.
333          */
334
335         if (type != RFC2047_ADDRESS)
336                 return 0;
337
338         /* '=' and '_' are special cases and have been checked above */
339         return !(isalnum(ch) || ch == '!' || ch == '*' || ch == '+' || ch == '-' || ch == '/');
340 }
341
342 static int needs_rfc2047_encoding(const char *line, int len,
343                                   enum rfc2047_type type)
344 {
345         int i;
346
347         for (i = 0; i < len; i++) {
348                 int ch = line[i];
349                 if (non_ascii(ch) || ch == '\n')
350                         return 1;
351                 if ((i + 1 < len) && (ch == '=' && line[i+1] == '?'))
352                         return 1;
353         }
354
355         return 0;
356 }
357
358 static void add_rfc2047(struct strbuf *sb, const char *line, size_t len,
359                        const char *encoding, enum rfc2047_type type)
360 {
361         static const int max_encoded_length = 76; /* per rfc2047 */
362         int i;
363         int line_len = last_line_length(sb);
364
365         strbuf_grow(sb, len * 3 + strlen(encoding) + 100);
366         strbuf_addf(sb, "=?%s?q?", encoding);
367         line_len += strlen(encoding) + 5; /* 5 for =??q? */
368
369         while (len) {
370                 /*
371                  * RFC 2047, section 5 (3):
372                  *
373                  * Each 'encoded-word' MUST represent an integral number of
374                  * characters.  A multi-octet character may not be split across
375                  * adjacent 'encoded- word's.
376                  */
377                 const unsigned char *p = (const unsigned char *)line;
378                 int chrlen = mbs_chrlen(&line, &len, encoding);
379                 int is_special = (chrlen > 1) || is_rfc2047_special(*p, type);
380
381                 /* "=%02X" * chrlen, or the byte itself */
382                 const char *encoded_fmt = is_special ? "=%02X"    : "%c";
383                 int         encoded_len = is_special ? 3 * chrlen : 1;
384
385                 /*
386                  * According to RFC 2047, we could encode the special character
387                  * ' ' (space) with '_' (underscore) for readability. But many
388                  * programs do not understand this and just leave the
389                  * underscore in place. Thus, we do nothing special here, which
390                  * causes ' ' to be encoded as '=20', avoiding this problem.
391                  */
392
393                 if (line_len + encoded_len + 2 > max_encoded_length) {
394                         /* It won't fit with trailing "?=" --- break the line */
395                         strbuf_addf(sb, "?=\n =?%s?q?", encoding);
396                         line_len = strlen(encoding) + 5 + 1; /* =??q? plus SP */
397                 }
398
399                 for (i = 0; i < chrlen; i++)
400                         strbuf_addf(sb, encoded_fmt, p[i]);
401                 line_len += encoded_len;
402         }
403         strbuf_addstr(sb, "?=");
404 }
405
406 const char *show_ident_date(const struct ident_split *ident,
407                             const struct date_mode *mode)
408 {
409         timestamp_t date = 0;
410         long tz = 0;
411
412         if (ident->date_begin && ident->date_end)
413                 date = parse_timestamp(ident->date_begin, NULL, 10);
414         if (date_overflows(date))
415                 date = 0;
416         else {
417                 if (ident->tz_begin && ident->tz_end)
418                         tz = strtol(ident->tz_begin, NULL, 10);
419                 if (tz >= INT_MAX || tz <= INT_MIN)
420                         tz = 0;
421         }
422         return show_date(date, tz, mode);
423 }
424
425 void pp_user_info(struct pretty_print_context *pp,
426                   const char *what, struct strbuf *sb,
427                   const char *line, const char *encoding)
428 {
429         struct ident_split ident;
430         char *line_end;
431         const char *mailbuf, *namebuf;
432         size_t namelen, maillen;
433         int max_length = 78; /* per rfc2822 */
434
435         if (pp->fmt == CMIT_FMT_ONELINE)
436                 return;
437
438         line_end = strchrnul(line, '\n');
439         if (split_ident_line(&ident, line, line_end - line))
440                 return;
441
442         mailbuf = ident.mail_begin;
443         maillen = ident.mail_end - ident.mail_begin;
444         namebuf = ident.name_begin;
445         namelen = ident.name_end - ident.name_begin;
446
447         if (pp->mailmap)
448                 map_user(pp->mailmap, &mailbuf, &maillen, &namebuf, &namelen);
449
450         if (cmit_fmt_is_mail(pp->fmt)) {
451                 if (pp->from_ident && ident_cmp(pp->from_ident, &ident)) {
452                         struct strbuf buf = STRBUF_INIT;
453
454                         strbuf_addstr(&buf, "From: ");
455                         strbuf_add(&buf, namebuf, namelen);
456                         strbuf_addstr(&buf, " <");
457                         strbuf_add(&buf, mailbuf, maillen);
458                         strbuf_addstr(&buf, ">\n");
459                         string_list_append(&pp->in_body_headers,
460                                            strbuf_detach(&buf, NULL));
461
462                         mailbuf = pp->from_ident->mail_begin;
463                         maillen = pp->from_ident->mail_end - mailbuf;
464                         namebuf = pp->from_ident->name_begin;
465                         namelen = pp->from_ident->name_end - namebuf;
466                 }
467
468                 strbuf_addstr(sb, "From: ");
469                 if (needs_rfc2047_encoding(namebuf, namelen, RFC2047_ADDRESS)) {
470                         add_rfc2047(sb, namebuf, namelen,
471                                     encoding, RFC2047_ADDRESS);
472                         max_length = 76; /* per rfc2047 */
473                 } else if (needs_rfc822_quoting(namebuf, namelen)) {
474                         struct strbuf quoted = STRBUF_INIT;
475                         add_rfc822_quoted(&quoted, namebuf, namelen);
476                         strbuf_add_wrapped_bytes(sb, quoted.buf, quoted.len,
477                                                         -6, 1, max_length);
478                         strbuf_release(&quoted);
479                 } else {
480                         strbuf_add_wrapped_bytes(sb, namebuf, namelen,
481                                                  -6, 1, max_length);
482                 }
483
484                 if (max_length <
485                     last_line_length(sb) + strlen(" <") + maillen + strlen(">"))
486                         strbuf_addch(sb, '\n');
487                 strbuf_addf(sb, " <%.*s>\n", (int)maillen, mailbuf);
488         } else {
489                 strbuf_addf(sb, "%s: %.*s%.*s <%.*s>\n", what,
490                             (pp->fmt == CMIT_FMT_FULLER) ? 4 : 0, "    ",
491                             (int)namelen, namebuf, (int)maillen, mailbuf);
492         }
493
494         switch (pp->fmt) {
495         case CMIT_FMT_MEDIUM:
496                 strbuf_addf(sb, "Date:   %s\n",
497                             show_ident_date(&ident, &pp->date_mode));
498                 break;
499         case CMIT_FMT_EMAIL:
500         case CMIT_FMT_MBOXRD:
501                 strbuf_addf(sb, "Date: %s\n",
502                             show_ident_date(&ident, DATE_MODE(RFC2822)));
503                 break;
504         case CMIT_FMT_FULLER:
505                 strbuf_addf(sb, "%sDate: %s\n", what,
506                             show_ident_date(&ident, &pp->date_mode));
507                 break;
508         default:
509                 /* notin' */
510                 break;
511         }
512 }
513
514 static int is_blank_line(const char *line, int *len_p)
515 {
516         int len = *len_p;
517         while (len && isspace(line[len - 1]))
518                 len--;
519         *len_p = len;
520         return !len;
521 }
522
523 const char *skip_blank_lines(const char *msg)
524 {
525         for (;;) {
526                 int linelen = get_one_line(msg);
527                 int ll = linelen;
528                 if (!linelen)
529                         break;
530                 if (!is_blank_line(msg, &ll))
531                         break;
532                 msg += linelen;
533         }
534         return msg;
535 }
536
537 static void add_merge_info(const struct pretty_print_context *pp,
538                            struct strbuf *sb, const struct commit *commit)
539 {
540         struct commit_list *parent = commit->parents;
541
542         if ((pp->fmt == CMIT_FMT_ONELINE) || (cmit_fmt_is_mail(pp->fmt)) ||
543             !parent || !parent->next)
544                 return;
545
546         strbuf_addstr(sb, "Merge:");
547
548         while (parent) {
549                 struct object_id *oidp = &parent->item->object.oid;
550                 strbuf_addch(sb, ' ');
551                 if (pp->abbrev)
552                         strbuf_add_unique_abbrev(sb, oidp, pp->abbrev);
553                 else
554                         strbuf_addstr(sb, oid_to_hex(oidp));
555                 parent = parent->next;
556         }
557         strbuf_addch(sb, '\n');
558 }
559
560 static char *get_header(const char *msg, const char *key)
561 {
562         size_t len;
563         const char *v = find_commit_header(msg, key, &len);
564         return v ? xmemdupz(v, len) : NULL;
565 }
566
567 static char *replace_encoding_header(char *buf, const char *encoding)
568 {
569         struct strbuf tmp = STRBUF_INIT;
570         size_t start, len;
571         char *cp = buf;
572
573         /* guess if there is an encoding header before a \n\n */
574         while (!starts_with(cp, "encoding ")) {
575                 cp = strchr(cp, '\n');
576                 if (!cp || *++cp == '\n')
577                         return buf;
578         }
579         start = cp - buf;
580         cp = strchr(cp, '\n');
581         if (!cp)
582                 return buf; /* should not happen but be defensive */
583         len = cp + 1 - (buf + start);
584
585         strbuf_attach(&tmp, buf, strlen(buf), strlen(buf) + 1);
586         if (is_encoding_utf8(encoding)) {
587                 /* we have re-coded to UTF-8; drop the header */
588                 strbuf_remove(&tmp, start, len);
589         } else {
590                 /* just replaces XXXX in 'encoding XXXX\n' */
591                 strbuf_splice(&tmp, start + strlen("encoding "),
592                                           len - strlen("encoding \n"),
593                                           encoding, strlen(encoding));
594         }
595         return strbuf_detach(&tmp, NULL);
596 }
597
598 const char *logmsg_reencode(const struct commit *commit,
599                             char **commit_encoding,
600                             const char *output_encoding)
601 {
602         static const char *utf8 = "UTF-8";
603         const char *use_encoding;
604         char *encoding;
605         const char *msg = get_commit_buffer(commit, NULL);
606         char *out;
607
608         if (!output_encoding || !*output_encoding) {
609                 if (commit_encoding)
610                         *commit_encoding = get_header(msg, "encoding");
611                 return msg;
612         }
613         encoding = get_header(msg, "encoding");
614         if (commit_encoding)
615                 *commit_encoding = encoding;
616         use_encoding = encoding ? encoding : utf8;
617         if (same_encoding(use_encoding, output_encoding)) {
618                 /*
619                  * No encoding work to be done. If we have no encoding header
620                  * at all, then there's nothing to do, and we can return the
621                  * message verbatim (whether newly allocated or not).
622                  */
623                 if (!encoding)
624                         return msg;
625
626                 /*
627                  * Otherwise, we still want to munge the encoding header in the
628                  * result, which will be done by modifying the buffer. If we
629                  * are using a fresh copy, we can reuse it. But if we are using
630                  * the cached copy from get_commit_buffer, we need to duplicate it
631                  * to avoid munging the cached copy.
632                  */
633                 if (msg == get_cached_commit_buffer(the_repository, commit, NULL))
634                         out = xstrdup(msg);
635                 else
636                         out = (char *)msg;
637         }
638         else {
639                 /*
640                  * There's actual encoding work to do. Do the reencoding, which
641                  * still leaves the header to be replaced in the next step. At
642                  * this point, we are done with msg. If we allocated a fresh
643                  * copy, we can free it.
644                  */
645                 out = reencode_string(msg, output_encoding, use_encoding);
646                 if (out)
647                         unuse_commit_buffer(commit, msg);
648         }
649
650         /*
651          * This replacement actually consumes the buffer we hand it, so we do
652          * not have to worry about freeing the old "out" here.
653          */
654         if (out)
655                 out = replace_encoding_header(out, output_encoding);
656
657         if (!commit_encoding)
658                 free(encoding);
659         /*
660          * If the re-encoding failed, out might be NULL here; in that
661          * case we just return the commit message verbatim.
662          */
663         return out ? out : msg;
664 }
665
666 static int mailmap_name(const char **email, size_t *email_len,
667                         const char **name, size_t *name_len)
668 {
669         static struct string_list *mail_map;
670         if (!mail_map) {
671                 mail_map = xcalloc(1, sizeof(*mail_map));
672                 read_mailmap(mail_map, NULL);
673         }
674         return mail_map->nr && map_user(mail_map, email, email_len, name, name_len);
675 }
676
677 static size_t format_person_part(struct strbuf *sb, char part,
678                                  const char *msg, int len,
679                                  const struct date_mode *dmode)
680 {
681         /* currently all placeholders have same length */
682         const int placeholder_len = 2;
683         struct ident_split s;
684         const char *name, *mail;
685         size_t maillen, namelen;
686
687         if (split_ident_line(&s, msg, len) < 0)
688                 goto skip;
689
690         name = s.name_begin;
691         namelen = s.name_end - s.name_begin;
692         mail = s.mail_begin;
693         maillen = s.mail_end - s.mail_begin;
694
695         if (part == 'N' || part == 'E') /* mailmap lookup */
696                 mailmap_name(&mail, &maillen, &name, &namelen);
697         if (part == 'n' || part == 'N') {       /* name */
698                 strbuf_add(sb, name, namelen);
699                 return placeholder_len;
700         }
701         if (part == 'e' || part == 'E') {       /* email */
702                 strbuf_add(sb, mail, maillen);
703                 return placeholder_len;
704         }
705
706         if (!s.date_begin)
707                 goto skip;
708
709         if (part == 't') {      /* date, UNIX timestamp */
710                 strbuf_add(sb, s.date_begin, s.date_end - s.date_begin);
711                 return placeholder_len;
712         }
713
714         switch (part) {
715         case 'd':       /* date */
716                 strbuf_addstr(sb, show_ident_date(&s, dmode));
717                 return placeholder_len;
718         case 'D':       /* date, RFC2822 style */
719                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(RFC2822)));
720                 return placeholder_len;
721         case 'r':       /* date, relative */
722                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(RELATIVE)));
723                 return placeholder_len;
724         case 'i':       /* date, ISO 8601-like */
725                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(ISO8601)));
726                 return placeholder_len;
727         case 'I':       /* date, ISO 8601 strict */
728                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(ISO8601_STRICT)));
729                 return placeholder_len;
730         }
731
732 skip:
733         /*
734          * reading from either a bogus commit, or a reflog entry with
735          * %gn, %ge, etc.; 'sb' cannot be updated, but we still need
736          * to compute a valid return value.
737          */
738         if (part == 'n' || part == 'e' || part == 't' || part == 'd'
739             || part == 'D' || part == 'r' || part == 'i')
740                 return placeholder_len;
741
742         return 0; /* unknown placeholder */
743 }
744
745 struct chunk {
746         size_t off;
747         size_t len;
748 };
749
750 enum flush_type {
751         no_flush,
752         flush_right,
753         flush_left,
754         flush_left_and_steal,
755         flush_both
756 };
757
758 enum trunc_type {
759         trunc_none,
760         trunc_left,
761         trunc_middle,
762         trunc_right
763 };
764
765 struct format_commit_context {
766         const struct commit *commit;
767         const struct pretty_print_context *pretty_ctx;
768         unsigned commit_header_parsed:1;
769         unsigned commit_message_parsed:1;
770         struct signature_check signature_check;
771         enum flush_type flush_type;
772         enum trunc_type truncate;
773         const char *message;
774         char *commit_encoding;
775         size_t width, indent1, indent2;
776         int auto_color;
777         int padding;
778
779         /* These offsets are relative to the start of the commit message. */
780         struct chunk author;
781         struct chunk committer;
782         size_t message_off;
783         size_t subject_off;
784         size_t body_off;
785
786         /* The following ones are relative to the result struct strbuf. */
787         size_t wrap_start;
788 };
789
790 static void parse_commit_header(struct format_commit_context *context)
791 {
792         const char *msg = context->message;
793         int i;
794
795         for (i = 0; msg[i]; i++) {
796                 const char *name;
797                 int eol;
798                 for (eol = i; msg[eol] && msg[eol] != '\n'; eol++)
799                         ; /* do nothing */
800
801                 if (i == eol) {
802                         break;
803                 } else if (skip_prefix(msg + i, "author ", &name)) {
804                         context->author.off = name - msg;
805                         context->author.len = msg + eol - name;
806                 } else if (skip_prefix(msg + i, "committer ", &name)) {
807                         context->committer.off = name - msg;
808                         context->committer.len = msg + eol - name;
809                 }
810                 i = eol;
811         }
812         context->message_off = i;
813         context->commit_header_parsed = 1;
814 }
815
816 static int istitlechar(char c)
817 {
818         return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
819                 (c >= '0' && c <= '9') || c == '.' || c == '_';
820 }
821
822 static void format_sanitized_subject(struct strbuf *sb, const char *msg)
823 {
824         size_t trimlen;
825         size_t start_len = sb->len;
826         int space = 2;
827
828         for (; *msg && *msg != '\n'; msg++) {
829                 if (istitlechar(*msg)) {
830                         if (space == 1)
831                                 strbuf_addch(sb, '-');
832                         space = 0;
833                         strbuf_addch(sb, *msg);
834                         if (*msg == '.')
835                                 while (*(msg+1) == '.')
836                                         msg++;
837                 } else
838                         space |= 1;
839         }
840
841         /* trim any trailing '.' or '-' characters */
842         trimlen = 0;
843         while (sb->len - trimlen > start_len &&
844                 (sb->buf[sb->len - 1 - trimlen] == '.'
845                 || sb->buf[sb->len - 1 - trimlen] == '-'))
846                 trimlen++;
847         strbuf_remove(sb, sb->len - trimlen, trimlen);
848 }
849
850 const char *format_subject(struct strbuf *sb, const char *msg,
851                            const char *line_separator)
852 {
853         int first = 1;
854
855         for (;;) {
856                 const char *line = msg;
857                 int linelen = get_one_line(line);
858
859                 msg += linelen;
860                 if (!linelen || is_blank_line(line, &linelen))
861                         break;
862
863                 if (!sb)
864                         continue;
865                 strbuf_grow(sb, linelen + 2);
866                 if (!first)
867                         strbuf_addstr(sb, line_separator);
868                 strbuf_add(sb, line, linelen);
869                 first = 0;
870         }
871         return msg;
872 }
873
874 static void parse_commit_message(struct format_commit_context *c)
875 {
876         const char *msg = c->message + c->message_off;
877         const char *start = c->message;
878
879         msg = skip_blank_lines(msg);
880         c->subject_off = msg - start;
881
882         msg = format_subject(NULL, msg, NULL);
883         msg = skip_blank_lines(msg);
884         c->body_off = msg - start;
885
886         c->commit_message_parsed = 1;
887 }
888
889 static void strbuf_wrap(struct strbuf *sb, size_t pos,
890                         size_t width, size_t indent1, size_t indent2)
891 {
892         struct strbuf tmp = STRBUF_INIT;
893
894         if (pos)
895                 strbuf_add(&tmp, sb->buf, pos);
896         strbuf_add_wrapped_text(&tmp, sb->buf + pos,
897                                 (int) indent1, (int) indent2, (int) width);
898         strbuf_swap(&tmp, sb);
899         strbuf_release(&tmp);
900 }
901
902 static void rewrap_message_tail(struct strbuf *sb,
903                                 struct format_commit_context *c,
904                                 size_t new_width, size_t new_indent1,
905                                 size_t new_indent2)
906 {
907         if (c->width == new_width && c->indent1 == new_indent1 &&
908             c->indent2 == new_indent2)
909                 return;
910         if (c->wrap_start < sb->len)
911                 strbuf_wrap(sb, c->wrap_start, c->width, c->indent1, c->indent2);
912         c->wrap_start = sb->len;
913         c->width = new_width;
914         c->indent1 = new_indent1;
915         c->indent2 = new_indent2;
916 }
917
918 static int format_reflog_person(struct strbuf *sb,
919                                 char part,
920                                 struct reflog_walk_info *log,
921                                 const struct date_mode *dmode)
922 {
923         const char *ident;
924
925         if (!log)
926                 return 2;
927
928         ident = get_reflog_ident(log);
929         if (!ident)
930                 return 2;
931
932         return format_person_part(sb, part, ident, strlen(ident), dmode);
933 }
934
935 static size_t parse_color(struct strbuf *sb, /* in UTF-8 */
936                           const char *placeholder,
937                           struct format_commit_context *c)
938 {
939         const char *rest = placeholder;
940         const char *basic_color = NULL;
941
942         if (placeholder[1] == '(') {
943                 const char *begin = placeholder + 2;
944                 const char *end = strchr(begin, ')');
945                 char color[COLOR_MAXLEN];
946
947                 if (!end)
948                         return 0;
949
950                 if (skip_prefix(begin, "auto,", &begin)) {
951                         if (!want_color(c->pretty_ctx->color))
952                                 return end - placeholder + 1;
953                 } else if (skip_prefix(begin, "always,", &begin)) {
954                         /* nothing to do; we do not respect want_color at all */
955                 } else {
956                         /* the default is the same as "auto" */
957                         if (!want_color(c->pretty_ctx->color))
958                                 return end - placeholder + 1;
959                 }
960
961                 if (color_parse_mem(begin, end - begin, color) < 0)
962                         die(_("unable to parse --pretty format"));
963                 strbuf_addstr(sb, color);
964                 return end - placeholder + 1;
965         }
966
967         /*
968          * We handle things like "%C(red)" above; for historical reasons, there
969          * are a few colors that can be specified without parentheses (and
970          * they cannot support things like "auto" or "always" at all).
971          */
972         if (skip_prefix(placeholder + 1, "red", &rest))
973                 basic_color = GIT_COLOR_RED;
974         else if (skip_prefix(placeholder + 1, "green", &rest))
975                 basic_color = GIT_COLOR_GREEN;
976         else if (skip_prefix(placeholder + 1, "blue", &rest))
977                 basic_color = GIT_COLOR_BLUE;
978         else if (skip_prefix(placeholder + 1, "reset", &rest))
979                 basic_color = GIT_COLOR_RESET;
980
981         if (basic_color && want_color(c->pretty_ctx->color))
982                 strbuf_addstr(sb, basic_color);
983
984         return rest - placeholder;
985 }
986
987 static size_t parse_padding_placeholder(struct strbuf *sb,
988                                         const char *placeholder,
989                                         struct format_commit_context *c)
990 {
991         const char *ch = placeholder;
992         enum flush_type flush_type;
993         int to_column = 0;
994
995         switch (*ch++) {
996         case '<':
997                 flush_type = flush_right;
998                 break;
999         case '>':
1000                 if (*ch == '<') {
1001                         flush_type = flush_both;
1002                         ch++;
1003                 } else if (*ch == '>') {
1004                         flush_type = flush_left_and_steal;
1005                         ch++;
1006                 } else
1007                         flush_type = flush_left;
1008                 break;
1009         default:
1010                 return 0;
1011         }
1012
1013         /* the next value means "wide enough to that column" */
1014         if (*ch == '|') {
1015                 to_column = 1;
1016                 ch++;
1017         }
1018
1019         if (*ch == '(') {
1020                 const char *start = ch + 1;
1021                 const char *end = start + strcspn(start, ",)");
1022                 char *next;
1023                 int width;
1024                 if (!end || end == start)
1025                         return 0;
1026                 width = strtol(start, &next, 10);
1027                 if (next == start || width == 0)
1028                         return 0;
1029                 if (width < 0) {
1030                         if (to_column)
1031                                 width += term_columns();
1032                         if (width < 0)
1033                                 return 0;
1034                 }
1035                 c->padding = to_column ? -width : width;
1036                 c->flush_type = flush_type;
1037
1038                 if (*end == ',') {
1039                         start = end + 1;
1040                         end = strchr(start, ')');
1041                         if (!end || end == start)
1042                                 return 0;
1043                         if (starts_with(start, "trunc)"))
1044                                 c->truncate = trunc_right;
1045                         else if (starts_with(start, "ltrunc)"))
1046                                 c->truncate = trunc_left;
1047                         else if (starts_with(start, "mtrunc)"))
1048                                 c->truncate = trunc_middle;
1049                         else
1050                                 return 0;
1051                 } else
1052                         c->truncate = trunc_none;
1053
1054                 return end - placeholder + 1;
1055         }
1056         return 0;
1057 }
1058
1059 static int match_placeholder_arg_value(const char *to_parse, const char *candidate,
1060                                        const char **end, const char **valuestart,
1061                                        size_t *valuelen)
1062 {
1063         const char *p;
1064
1065         if (!(skip_prefix(to_parse, candidate, &p)))
1066                 return 0;
1067         if (valuestart) {
1068                 if (*p == '=') {
1069                         *valuestart = p + 1;
1070                         *valuelen = strcspn(*valuestart, ",)");
1071                         p = *valuestart + *valuelen;
1072                 } else {
1073                         if (*p != ',' && *p != ')')
1074                                 return 0;
1075                         *valuestart = NULL;
1076                         *valuelen = 0;
1077                 }
1078         }
1079         if (*p == ',') {
1080                 *end = p + 1;
1081                 return 1;
1082         }
1083         if (*p == ')') {
1084                 *end = p;
1085                 return 1;
1086         }
1087         return 0;
1088 }
1089
1090 static int match_placeholder_bool_arg(const char *to_parse, const char *candidate,
1091                                       const char **end, int *val)
1092 {
1093         const char *argval;
1094         char *strval;
1095         size_t arglen;
1096         int v;
1097
1098         if (!match_placeholder_arg_value(to_parse, candidate, end, &argval, &arglen))
1099                 return 0;
1100
1101         if (!argval) {
1102                 *val = 1;
1103                 return 1;
1104         }
1105
1106         strval = xstrndup(argval, arglen);
1107         v = git_parse_maybe_bool(strval);
1108         free(strval);
1109
1110         if (v == -1)
1111                 return 0;
1112
1113         *val = v;
1114
1115         return 1;
1116 }
1117
1118 static int format_trailer_match_cb(const struct strbuf *key, void *ud)
1119 {
1120         const struct string_list *list = ud;
1121         const struct string_list_item *item;
1122
1123         for_each_string_list_item (item, list) {
1124                 if (key->len == (uintptr_t)item->util &&
1125                     !strncasecmp(item->string, key->buf, key->len))
1126                         return 1;
1127         }
1128         return 0;
1129 }
1130
1131 static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
1132                                 const char *placeholder,
1133                                 void *context)
1134 {
1135         struct format_commit_context *c = context;
1136         const struct commit *commit = c->commit;
1137         const char *msg = c->message;
1138         struct commit_list *p;
1139         const char *arg;
1140         size_t res;
1141
1142         /* these are independent of the commit */
1143         res = strbuf_expand_literal_cb(sb, placeholder, NULL);
1144         if (res)
1145                 return res;
1146
1147         switch (placeholder[0]) {
1148         case 'C':
1149                 if (starts_with(placeholder + 1, "(auto)")) {
1150                         c->auto_color = want_color(c->pretty_ctx->color);
1151                         if (c->auto_color && sb->len)
1152                                 strbuf_addstr(sb, GIT_COLOR_RESET);
1153                         return 7; /* consumed 7 bytes, "C(auto)" */
1154                 } else {
1155                         int ret = parse_color(sb, placeholder, c);
1156                         if (ret)
1157                                 c->auto_color = 0;
1158                         /*
1159                          * Otherwise, we decided to treat %C<unknown>
1160                          * as a literal string, and the previous
1161                          * %C(auto) is still valid.
1162                          */
1163                         return ret;
1164                 }
1165         case 'w':
1166                 if (placeholder[1] == '(') {
1167                         unsigned long width = 0, indent1 = 0, indent2 = 0;
1168                         char *next;
1169                         const char *start = placeholder + 2;
1170                         const char *end = strchr(start, ')');
1171                         if (!end)
1172                                 return 0;
1173                         if (end > start) {
1174                                 width = strtoul(start, &next, 10);
1175                                 if (*next == ',') {
1176                                         indent1 = strtoul(next + 1, &next, 10);
1177                                         if (*next == ',') {
1178                                                 indent2 = strtoul(next + 1,
1179                                                                  &next, 10);
1180                                         }
1181                                 }
1182                                 if (*next != ')')
1183                                         return 0;
1184                         }
1185                         rewrap_message_tail(sb, c, width, indent1, indent2);
1186                         return end - placeholder + 1;
1187                 } else
1188                         return 0;
1189
1190         case '<':
1191         case '>':
1192                 return parse_padding_placeholder(sb, placeholder, c);
1193         }
1194
1195         /* these depend on the commit */
1196         if (!commit->object.parsed)
1197                 parse_object(the_repository, &commit->object.oid);
1198
1199         switch (placeholder[0]) {
1200         case 'H':               /* commit hash */
1201                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_COMMIT));
1202                 strbuf_addstr(sb, oid_to_hex(&commit->object.oid));
1203                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_RESET));
1204                 return 1;
1205         case 'h':               /* abbreviated commit hash */
1206                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_COMMIT));
1207                 strbuf_add_unique_abbrev(sb, &commit->object.oid,
1208                                          c->pretty_ctx->abbrev);
1209                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_RESET));
1210                 return 1;
1211         case 'T':               /* tree hash */
1212                 strbuf_addstr(sb, oid_to_hex(get_commit_tree_oid(commit)));
1213                 return 1;
1214         case 't':               /* abbreviated tree hash */
1215                 strbuf_add_unique_abbrev(sb,
1216                                          get_commit_tree_oid(commit),
1217                                          c->pretty_ctx->abbrev);
1218                 return 1;
1219         case 'P':               /* parent hashes */
1220                 for (p = commit->parents; p; p = p->next) {
1221                         if (p != commit->parents)
1222                                 strbuf_addch(sb, ' ');
1223                         strbuf_addstr(sb, oid_to_hex(&p->item->object.oid));
1224                 }
1225                 return 1;
1226         case 'p':               /* abbreviated parent hashes */
1227                 for (p = commit->parents; p; p = p->next) {
1228                         if (p != commit->parents)
1229                                 strbuf_addch(sb, ' ');
1230                         strbuf_add_unique_abbrev(sb, &p->item->object.oid,
1231                                                  c->pretty_ctx->abbrev);
1232                 }
1233                 return 1;
1234         case 'm':               /* left/right/bottom */
1235                 strbuf_addstr(sb, get_revision_mark(NULL, commit));
1236                 return 1;
1237         case 'd':
1238                 load_ref_decorations(NULL, DECORATE_SHORT_REFS);
1239                 format_decorations(sb, commit, c->auto_color);
1240                 return 1;
1241         case 'D':
1242                 load_ref_decorations(NULL, DECORATE_SHORT_REFS);
1243                 format_decorations_extended(sb, commit, c->auto_color, "", ", ", "");
1244                 return 1;
1245         case 'g':               /* reflog info */
1246                 switch(placeholder[1]) {
1247                 case 'd':       /* reflog selector */
1248                 case 'D':
1249                         if (c->pretty_ctx->reflog_info)
1250                                 get_reflog_selector(sb,
1251                                                     c->pretty_ctx->reflog_info,
1252                                                     &c->pretty_ctx->date_mode,
1253                                                     c->pretty_ctx->date_mode_explicit,
1254                                                     (placeholder[1] == 'd'));
1255                         return 2;
1256                 case 's':       /* reflog message */
1257                         if (c->pretty_ctx->reflog_info)
1258                                 get_reflog_message(sb, c->pretty_ctx->reflog_info);
1259                         return 2;
1260                 case 'n':
1261                 case 'N':
1262                 case 'e':
1263                 case 'E':
1264                         return format_reflog_person(sb,
1265                                                     placeholder[1],
1266                                                     c->pretty_ctx->reflog_info,
1267                                                     &c->pretty_ctx->date_mode);
1268                 }
1269                 return 0;       /* unknown %g placeholder */
1270         case 'N':
1271                 if (c->pretty_ctx->notes_message) {
1272                         strbuf_addstr(sb, c->pretty_ctx->notes_message);
1273                         return 1;
1274                 }
1275                 return 0;
1276         }
1277
1278         if (placeholder[0] == 'G') {
1279                 if (!c->signature_check.result)
1280                         check_commit_signature(c->commit, &(c->signature_check));
1281                 switch (placeholder[1]) {
1282                 case 'G':
1283                         if (c->signature_check.gpg_output)
1284                                 strbuf_addstr(sb, c->signature_check.gpg_output);
1285                         break;
1286                 case '?':
1287                         switch (c->signature_check.result) {
1288                         case 'G':
1289                         case 'B':
1290                         case 'E':
1291                         case 'U':
1292                         case 'N':
1293                         case 'X':
1294                         case 'Y':
1295                         case 'R':
1296                                 strbuf_addch(sb, c->signature_check.result);
1297                         }
1298                         break;
1299                 case 'S':
1300                         if (c->signature_check.signer)
1301                                 strbuf_addstr(sb, c->signature_check.signer);
1302                         break;
1303                 case 'K':
1304                         if (c->signature_check.key)
1305                                 strbuf_addstr(sb, c->signature_check.key);
1306                         break;
1307                 case 'F':
1308                         if (c->signature_check.fingerprint)
1309                                 strbuf_addstr(sb, c->signature_check.fingerprint);
1310                         break;
1311                 case 'P':
1312                         if (c->signature_check.primary_key_fingerprint)
1313                                 strbuf_addstr(sb, c->signature_check.primary_key_fingerprint);
1314                         break;
1315                 default:
1316                         return 0;
1317                 }
1318                 return 2;
1319         }
1320
1321
1322         /* For the rest we have to parse the commit header. */
1323         if (!c->commit_header_parsed)
1324                 parse_commit_header(c);
1325
1326         switch (placeholder[0]) {
1327         case 'a':       /* author ... */
1328                 return format_person_part(sb, placeholder[1],
1329                                    msg + c->author.off, c->author.len,
1330                                    &c->pretty_ctx->date_mode);
1331         case 'c':       /* committer ... */
1332                 return format_person_part(sb, placeholder[1],
1333                                    msg + c->committer.off, c->committer.len,
1334                                    &c->pretty_ctx->date_mode);
1335         case 'e':       /* encoding */
1336                 if (c->commit_encoding)
1337                         strbuf_addstr(sb, c->commit_encoding);
1338                 return 1;
1339         case 'B':       /* raw body */
1340                 /* message_off is always left at the initial newline */
1341                 strbuf_addstr(sb, msg + c->message_off + 1);
1342                 return 1;
1343         }
1344
1345         /* Now we need to parse the commit message. */
1346         if (!c->commit_message_parsed)
1347                 parse_commit_message(c);
1348
1349         switch (placeholder[0]) {
1350         case 's':       /* subject */
1351                 format_subject(sb, msg + c->subject_off, " ");
1352                 return 1;
1353         case 'f':       /* sanitized subject */
1354                 format_sanitized_subject(sb, msg + c->subject_off);
1355                 return 1;
1356         case 'b':       /* body */
1357                 strbuf_addstr(sb, msg + c->body_off);
1358                 return 1;
1359         }
1360
1361         if (skip_prefix(placeholder, "(trailers", &arg)) {
1362                 struct process_trailer_options opts = PROCESS_TRAILER_OPTIONS_INIT;
1363                 struct string_list filter_list = STRING_LIST_INIT_NODUP;
1364                 size_t ret = 0;
1365
1366                 opts.no_divider = 1;
1367
1368                 if (*arg == ':') {
1369                         arg++;
1370                         for (;;) {
1371                                 const char *argval;
1372                                 size_t arglen;
1373
1374                                 if (match_placeholder_arg_value(arg, "key", &arg, &argval, &arglen)) {
1375                                         uintptr_t len = arglen;
1376
1377                                         if (!argval)
1378                                                 goto trailer_out;
1379
1380                                         if (len && argval[len - 1] == ':')
1381                                                 len--;
1382                                         string_list_append(&filter_list, argval)->util = (char *)len;
1383
1384                                         opts.filter = format_trailer_match_cb;
1385                                         opts.filter_data = &filter_list;
1386                                         opts.only_trailers = 1;
1387                                 } else if (!match_placeholder_bool_arg(arg, "only", &arg, &opts.only_trailers) &&
1388                                            !match_placeholder_bool_arg(arg, "unfold", &arg, &opts.unfold) &&
1389                                            !match_placeholder_bool_arg(arg, "valueonly", &arg, &opts.value_only))
1390                                         break;
1391                         }
1392                 }
1393                 if (*arg == ')') {
1394                         format_trailers_from_commit(sb, msg + c->subject_off, &opts);
1395                         ret = arg - placeholder + 1;
1396                 }
1397         trailer_out:
1398                 string_list_clear(&filter_list, 0);
1399                 return ret;
1400         }
1401
1402         return 0;       /* unknown placeholder */
1403 }
1404
1405 static size_t format_and_pad_commit(struct strbuf *sb, /* in UTF-8 */
1406                                     const char *placeholder,
1407                                     struct format_commit_context *c)
1408 {
1409         struct strbuf local_sb = STRBUF_INIT;
1410         int total_consumed = 0, len, padding = c->padding;
1411         if (padding < 0) {
1412                 const char *start = strrchr(sb->buf, '\n');
1413                 int occupied;
1414                 if (!start)
1415                         start = sb->buf;
1416                 occupied = utf8_strnwidth(start, -1, 1);
1417                 occupied += c->pretty_ctx->graph_width;
1418                 padding = (-padding) - occupied;
1419         }
1420         while (1) {
1421                 int modifier = *placeholder == 'C';
1422                 int consumed = format_commit_one(&local_sb, placeholder, c);
1423                 total_consumed += consumed;
1424
1425                 if (!modifier)
1426                         break;
1427
1428                 placeholder += consumed;
1429                 if (*placeholder != '%')
1430                         break;
1431                 placeholder++;
1432                 total_consumed++;
1433         }
1434         len = utf8_strnwidth(local_sb.buf, -1, 1);
1435
1436         if (c->flush_type == flush_left_and_steal) {
1437                 const char *ch = sb->buf + sb->len - 1;
1438                 while (len > padding && ch > sb->buf) {
1439                         const char *p;
1440                         if (*ch == ' ') {
1441                                 ch--;
1442                                 padding++;
1443                                 continue;
1444                         }
1445                         /* check for trailing ansi sequences */
1446                         if (*ch != 'm')
1447                                 break;
1448                         p = ch - 1;
1449                         while (ch - p < 10 && *p != '\033')
1450                                 p--;
1451                         if (*p != '\033' ||
1452                             ch + 1 - p != display_mode_esc_sequence_len(p))
1453                                 break;
1454                         /*
1455                          * got a good ansi sequence, put it back to
1456                          * local_sb as we're cutting sb
1457                          */
1458                         strbuf_insert(&local_sb, 0, p, ch + 1 - p);
1459                         ch = p - 1;
1460                 }
1461                 strbuf_setlen(sb, ch + 1 - sb->buf);
1462                 c->flush_type = flush_left;
1463         }
1464
1465         if (len > padding) {
1466                 switch (c->truncate) {
1467                 case trunc_left:
1468                         strbuf_utf8_replace(&local_sb,
1469                                             0, len - (padding - 2),
1470                                             "..");
1471                         break;
1472                 case trunc_middle:
1473                         strbuf_utf8_replace(&local_sb,
1474                                             padding / 2 - 1,
1475                                             len - (padding - 2),
1476                                             "..");
1477                         break;
1478                 case trunc_right:
1479                         strbuf_utf8_replace(&local_sb,
1480                                             padding - 2, len - (padding - 2),
1481                                             "..");
1482                         break;
1483                 case trunc_none:
1484                         break;
1485                 }
1486                 strbuf_addbuf(sb, &local_sb);
1487         } else {
1488                 int sb_len = sb->len, offset = 0;
1489                 if (c->flush_type == flush_left)
1490                         offset = padding - len;
1491                 else if (c->flush_type == flush_both)
1492                         offset = (padding - len) / 2;
1493                 /*
1494                  * we calculate padding in columns, now
1495                  * convert it back to chars
1496                  */
1497                 padding = padding - len + local_sb.len;
1498                 strbuf_addchars(sb, ' ', padding);
1499                 memcpy(sb->buf + sb_len + offset, local_sb.buf,
1500                        local_sb.len);
1501         }
1502         strbuf_release(&local_sb);
1503         c->flush_type = no_flush;
1504         return total_consumed;
1505 }
1506
1507 static size_t format_commit_item(struct strbuf *sb, /* in UTF-8 */
1508                                  const char *placeholder,
1509                                  void *context)
1510 {
1511         int consumed;
1512         size_t orig_len;
1513         enum {
1514                 NO_MAGIC,
1515                 ADD_LF_BEFORE_NON_EMPTY,
1516                 DEL_LF_BEFORE_EMPTY,
1517                 ADD_SP_BEFORE_NON_EMPTY
1518         } magic = NO_MAGIC;
1519
1520         switch (placeholder[0]) {
1521         case '-':
1522                 magic = DEL_LF_BEFORE_EMPTY;
1523                 break;
1524         case '+':
1525                 magic = ADD_LF_BEFORE_NON_EMPTY;
1526                 break;
1527         case ' ':
1528                 magic = ADD_SP_BEFORE_NON_EMPTY;
1529                 break;
1530         default:
1531                 break;
1532         }
1533         if (magic != NO_MAGIC)
1534                 placeholder++;
1535
1536         orig_len = sb->len;
1537         if (((struct format_commit_context *)context)->flush_type != no_flush)
1538                 consumed = format_and_pad_commit(sb, placeholder, context);
1539         else
1540                 consumed = format_commit_one(sb, placeholder, context);
1541         if (magic == NO_MAGIC)
1542                 return consumed;
1543
1544         if ((orig_len == sb->len) && magic == DEL_LF_BEFORE_EMPTY) {
1545                 while (sb->len && sb->buf[sb->len - 1] == '\n')
1546                         strbuf_setlen(sb, sb->len - 1);
1547         } else if (orig_len != sb->len) {
1548                 if (magic == ADD_LF_BEFORE_NON_EMPTY)
1549                         strbuf_insert(sb, orig_len, "\n", 1);
1550                 else if (magic == ADD_SP_BEFORE_NON_EMPTY)
1551                         strbuf_insert(sb, orig_len, " ", 1);
1552         }
1553         return consumed + 1;
1554 }
1555
1556 static size_t userformat_want_item(struct strbuf *sb, const char *placeholder,
1557                                    void *context)
1558 {
1559         struct userformat_want *w = context;
1560
1561         if (*placeholder == '+' || *placeholder == '-' || *placeholder == ' ')
1562                 placeholder++;
1563
1564         switch (*placeholder) {
1565         case 'N':
1566                 w->notes = 1;
1567                 break;
1568         }
1569         return 0;
1570 }
1571
1572 void userformat_find_requirements(const char *fmt, struct userformat_want *w)
1573 {
1574         struct strbuf dummy = STRBUF_INIT;
1575
1576         if (!fmt) {
1577                 if (!user_format)
1578                         return;
1579                 fmt = user_format;
1580         }
1581         strbuf_expand(&dummy, fmt, userformat_want_item, w);
1582         strbuf_release(&dummy);
1583 }
1584
1585 void format_commit_message(const struct commit *commit,
1586                            const char *format, struct strbuf *sb,
1587                            const struct pretty_print_context *pretty_ctx)
1588 {
1589         struct format_commit_context context;
1590         const char *output_enc = pretty_ctx->output_encoding;
1591         const char *utf8 = "UTF-8";
1592
1593         memset(&context, 0, sizeof(context));
1594         context.commit = commit;
1595         context.pretty_ctx = pretty_ctx;
1596         context.wrap_start = sb->len;
1597         /*
1598          * convert a commit message to UTF-8 first
1599          * as far as 'format_commit_item' assumes it in UTF-8
1600          */
1601         context.message = logmsg_reencode(commit,
1602                                           &context.commit_encoding,
1603                                           utf8);
1604
1605         strbuf_expand(sb, format, format_commit_item, &context);
1606         rewrap_message_tail(sb, &context, 0, 0, 0);
1607
1608         /* then convert a commit message to an actual output encoding */
1609         if (output_enc) {
1610                 if (same_encoding(utf8, output_enc))
1611                         output_enc = NULL;
1612         } else {
1613                 if (context.commit_encoding &&
1614                     !same_encoding(context.commit_encoding, utf8))
1615                         output_enc = context.commit_encoding;
1616         }
1617
1618         if (output_enc) {
1619                 size_t outsz;
1620                 char *out = reencode_string_len(sb->buf, sb->len,
1621                                                 output_enc, utf8, &outsz);
1622                 if (out)
1623                         strbuf_attach(sb, out, outsz, outsz + 1);
1624         }
1625
1626         free(context.commit_encoding);
1627         unuse_commit_buffer(commit, context.message);
1628 }
1629
1630 static void pp_header(struct pretty_print_context *pp,
1631                       const char *encoding,
1632                       const struct commit *commit,
1633                       const char **msg_p,
1634                       struct strbuf *sb)
1635 {
1636         int parents_shown = 0;
1637
1638         for (;;) {
1639                 const char *name, *line = *msg_p;
1640                 int linelen = get_one_line(*msg_p);
1641
1642                 if (!linelen)
1643                         return;
1644                 *msg_p += linelen;
1645
1646                 if (linelen == 1)
1647                         /* End of header */
1648                         return;
1649
1650                 if (pp->fmt == CMIT_FMT_RAW) {
1651                         strbuf_add(sb, line, linelen);
1652                         continue;
1653                 }
1654
1655                 if (starts_with(line, "parent ")) {
1656                         if (linelen != the_hash_algo->hexsz + 8)
1657                                 die("bad parent line in commit");
1658                         continue;
1659                 }
1660
1661                 if (!parents_shown) {
1662                         unsigned num = commit_list_count(commit->parents);
1663                         /* with enough slop */
1664                         strbuf_grow(sb, num * (GIT_MAX_HEXSZ + 10) + 20);
1665                         add_merge_info(pp, sb, commit);
1666                         parents_shown = 1;
1667                 }
1668
1669                 /*
1670                  * MEDIUM == DEFAULT shows only author with dates.
1671                  * FULL shows both authors but not dates.
1672                  * FULLER shows both authors and dates.
1673                  */
1674                 if (skip_prefix(line, "author ", &name)) {
1675                         strbuf_grow(sb, linelen + 80);
1676                         pp_user_info(pp, "Author", sb, name, encoding);
1677                 }
1678                 if (skip_prefix(line, "committer ", &name) &&
1679                     (pp->fmt == CMIT_FMT_FULL || pp->fmt == CMIT_FMT_FULLER)) {
1680                         strbuf_grow(sb, linelen + 80);
1681                         pp_user_info(pp, "Commit", sb, name, encoding);
1682                 }
1683         }
1684 }
1685
1686 void pp_title_line(struct pretty_print_context *pp,
1687                    const char **msg_p,
1688                    struct strbuf *sb,
1689                    const char *encoding,
1690                    int need_8bit_cte)
1691 {
1692         static const int max_length = 78; /* per rfc2047 */
1693         struct strbuf title;
1694
1695         strbuf_init(&title, 80);
1696         *msg_p = format_subject(&title, *msg_p,
1697                                 pp->preserve_subject ? "\n" : " ");
1698
1699         strbuf_grow(sb, title.len + 1024);
1700         if (pp->print_email_subject) {
1701                 if (pp->rev)
1702                         fmt_output_email_subject(sb, pp->rev);
1703                 if (needs_rfc2047_encoding(title.buf, title.len, RFC2047_SUBJECT))
1704                         add_rfc2047(sb, title.buf, title.len,
1705                                                 encoding, RFC2047_SUBJECT);
1706                 else
1707                         strbuf_add_wrapped_bytes(sb, title.buf, title.len,
1708                                          -last_line_length(sb), 1, max_length);
1709         } else {
1710                 strbuf_addbuf(sb, &title);
1711         }
1712         strbuf_addch(sb, '\n');
1713
1714         if (need_8bit_cte == 0) {
1715                 int i;
1716                 for (i = 0; i < pp->in_body_headers.nr; i++) {
1717                         if (has_non_ascii(pp->in_body_headers.items[i].string)) {
1718                                 need_8bit_cte = 1;
1719                                 break;
1720                         }
1721                 }
1722         }
1723
1724         if (need_8bit_cte > 0) {
1725                 const char *header_fmt =
1726                         "MIME-Version: 1.0\n"
1727                         "Content-Type: text/plain; charset=%s\n"
1728                         "Content-Transfer-Encoding: 8bit\n";
1729                 strbuf_addf(sb, header_fmt, encoding);
1730         }
1731         if (pp->after_subject) {
1732                 strbuf_addstr(sb, pp->after_subject);
1733         }
1734         if (cmit_fmt_is_mail(pp->fmt)) {
1735                 strbuf_addch(sb, '\n');
1736         }
1737
1738         if (pp->in_body_headers.nr) {
1739                 int i;
1740                 for (i = 0; i < pp->in_body_headers.nr; i++) {
1741                         strbuf_addstr(sb, pp->in_body_headers.items[i].string);
1742                         free(pp->in_body_headers.items[i].string);
1743                 }
1744                 string_list_clear(&pp->in_body_headers, 0);
1745                 strbuf_addch(sb, '\n');
1746         }
1747
1748         strbuf_release(&title);
1749 }
1750
1751 static int pp_utf8_width(const char *start, const char *end)
1752 {
1753         int width = 0;
1754         size_t remain = end - start;
1755
1756         while (remain) {
1757                 int n = utf8_width(&start, &remain);
1758                 if (n < 0 || !start)
1759                         return -1;
1760                 width += n;
1761         }
1762         return width;
1763 }
1764
1765 static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,
1766                                  const char *line, int linelen)
1767 {
1768         const char *tab;
1769
1770         while ((tab = memchr(line, '\t', linelen)) != NULL) {
1771                 int width = pp_utf8_width(line, tab);
1772
1773                 /*
1774                  * If it wasn't well-formed utf8, or it
1775                  * had characters with badly defined
1776                  * width (control characters etc), just
1777                  * give up on trying to align things.
1778                  */
1779                 if (width < 0)
1780                         break;
1781
1782                 /* Output the data .. */
1783                 strbuf_add(sb, line, tab - line);
1784
1785                 /* .. and the de-tabified tab */
1786                 strbuf_addchars(sb, ' ', tabwidth - (width % tabwidth));
1787
1788                 /* Skip over the printed part .. */
1789                 linelen -= tab + 1 - line;
1790                 line = tab + 1;
1791         }
1792
1793         /*
1794          * Print out everything after the last tab without
1795          * worrying about width - there's nothing more to
1796          * align.
1797          */
1798         strbuf_add(sb, line, linelen);
1799 }
1800
1801 /*
1802  * pp_handle_indent() prints out the intendation, and
1803  * the whole line (without the final newline), after
1804  * de-tabifying.
1805  */
1806 static void pp_handle_indent(struct pretty_print_context *pp,
1807                              struct strbuf *sb, int indent,
1808                              const char *line, int linelen)
1809 {
1810         strbuf_addchars(sb, ' ', indent);
1811         if (pp->expand_tabs_in_log)
1812                 strbuf_add_tabexpand(sb, pp->expand_tabs_in_log, line, linelen);
1813         else
1814                 strbuf_add(sb, line, linelen);
1815 }
1816
1817 static int is_mboxrd_from(const char *line, int len)
1818 {
1819         /*
1820          * a line matching /^From $/ here would only have len == 4
1821          * at this point because is_empty_line would've trimmed all
1822          * trailing space
1823          */
1824         return len > 4 && starts_with(line + strspn(line, ">"), "From ");
1825 }
1826
1827 void pp_remainder(struct pretty_print_context *pp,
1828                   const char **msg_p,
1829                   struct strbuf *sb,
1830                   int indent)
1831 {
1832         int first = 1;
1833         for (;;) {
1834                 const char *line = *msg_p;
1835                 int linelen = get_one_line(line);
1836                 *msg_p += linelen;
1837
1838                 if (!linelen)
1839                         break;
1840
1841                 if (is_blank_line(line, &linelen)) {
1842                         if (first)
1843                                 continue;
1844                         if (pp->fmt == CMIT_FMT_SHORT)
1845                                 break;
1846                 }
1847                 first = 0;
1848
1849                 strbuf_grow(sb, linelen + indent + 20);
1850                 if (indent)
1851                         pp_handle_indent(pp, sb, indent, line, linelen);
1852                 else if (pp->expand_tabs_in_log)
1853                         strbuf_add_tabexpand(sb, pp->expand_tabs_in_log,
1854                                              line, linelen);
1855                 else {
1856                         if (pp->fmt == CMIT_FMT_MBOXRD &&
1857                                         is_mboxrd_from(line, linelen))
1858                                 strbuf_addch(sb, '>');
1859
1860                         strbuf_add(sb, line, linelen);
1861                 }
1862                 strbuf_addch(sb, '\n');
1863         }
1864 }
1865
1866 void pretty_print_commit(struct pretty_print_context *pp,
1867                          const struct commit *commit,
1868                          struct strbuf *sb)
1869 {
1870         unsigned long beginning_of_body;
1871         int indent = 4;
1872         const char *msg;
1873         const char *reencoded;
1874         const char *encoding;
1875         int need_8bit_cte = pp->need_8bit_cte;
1876
1877         if (pp->fmt == CMIT_FMT_USERFORMAT) {
1878                 format_commit_message(commit, user_format, sb, pp);
1879                 return;
1880         }
1881
1882         encoding = get_log_output_encoding();
1883         msg = reencoded = logmsg_reencode(commit, NULL, encoding);
1884
1885         if (pp->fmt == CMIT_FMT_ONELINE || cmit_fmt_is_mail(pp->fmt))
1886                 indent = 0;
1887
1888         /*
1889          * We need to check and emit Content-type: to mark it
1890          * as 8-bit if we haven't done so.
1891          */
1892         if (cmit_fmt_is_mail(pp->fmt) && need_8bit_cte == 0) {
1893                 int i, ch, in_body;
1894
1895                 for (in_body = i = 0; (ch = msg[i]); i++) {
1896                         if (!in_body) {
1897                                 /* author could be non 7-bit ASCII but
1898                                  * the log may be so; skip over the
1899                                  * header part first.
1900                                  */
1901                                 if (ch == '\n' && msg[i+1] == '\n')
1902                                         in_body = 1;
1903                         }
1904                         else if (non_ascii(ch)) {
1905                                 need_8bit_cte = 1;
1906                                 break;
1907                         }
1908                 }
1909         }
1910
1911         pp_header(pp, encoding, commit, &msg, sb);
1912         if (pp->fmt != CMIT_FMT_ONELINE && !pp->print_email_subject) {
1913                 strbuf_addch(sb, '\n');
1914         }
1915
1916         /* Skip excess blank lines at the beginning of body, if any... */
1917         msg = skip_blank_lines(msg);
1918
1919         /* These formats treat the title line specially. */
1920         if (pp->fmt == CMIT_FMT_ONELINE || cmit_fmt_is_mail(pp->fmt))
1921                 pp_title_line(pp, &msg, sb, encoding, need_8bit_cte);
1922
1923         beginning_of_body = sb->len;
1924         if (pp->fmt != CMIT_FMT_ONELINE)
1925                 pp_remainder(pp, &msg, sb, indent);
1926         strbuf_rtrim(sb);
1927
1928         /* Make sure there is an EOLN for the non-oneline case */
1929         if (pp->fmt != CMIT_FMT_ONELINE)
1930                 strbuf_addch(sb, '\n');
1931
1932         /*
1933          * The caller may append additional body text in e-mail
1934          * format.  Make sure we did not strip the blank line
1935          * between the header and the body.
1936          */
1937         if (cmit_fmt_is_mail(pp->fmt) && sb->len <= beginning_of_body)
1938                 strbuf_addch(sb, '\n');
1939
1940         unuse_commit_buffer(commit, reencoded);
1941 }
1942
1943 void pp_commit_easy(enum cmit_fmt fmt, const struct commit *commit,
1944                     struct strbuf *sb)
1945 {
1946         struct pretty_print_context pp = {0};
1947         pp.fmt = fmt;
1948         pretty_print_commit(&pp, commit, sb);
1949 }