Merge branch 'ma/bisect-doc-sample-update'
[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                  * Please update $__git_log_pretty_formats in
103                  * git-completion.bash when you add new formats.
104                  */
105         };
106         commit_formats_len = ARRAY_SIZE(builtin_formats);
107         builtin_formats_len = commit_formats_len;
108         ALLOC_GROW(commit_formats, commit_formats_len, commit_formats_alloc);
109         COPY_ARRAY(commit_formats, builtin_formats,
110                    ARRAY_SIZE(builtin_formats));
111
112         git_config(git_pretty_formats_config, NULL);
113 }
114
115 static struct cmt_fmt_map *find_commit_format_recursive(const char *sought,
116                                                         const char *original,
117                                                         int num_redirections)
118 {
119         struct cmt_fmt_map *found = NULL;
120         size_t found_match_len = 0;
121         int i;
122
123         if (num_redirections >= commit_formats_len)
124                 die("invalid --pretty format: "
125                     "'%s' references an alias which points to itself",
126                     original);
127
128         for (i = 0; i < commit_formats_len; i++) {
129                 size_t match_len;
130
131                 if (!starts_with(commit_formats[i].name, sought))
132                         continue;
133
134                 match_len = strlen(commit_formats[i].name);
135                 if (found == NULL || found_match_len > match_len) {
136                         found = &commit_formats[i];
137                         found_match_len = match_len;
138                 }
139         }
140
141         if (found && found->is_alias) {
142                 found = find_commit_format_recursive(found->user_format,
143                                                      original,
144                                                      num_redirections+1);
145         }
146
147         return found;
148 }
149
150 static struct cmt_fmt_map *find_commit_format(const char *sought)
151 {
152         if (!commit_formats)
153                 setup_commit_formats();
154
155         return find_commit_format_recursive(sought, sought, 0);
156 }
157
158 void get_commit_format(const char *arg, struct rev_info *rev)
159 {
160         struct cmt_fmt_map *commit_format;
161
162         rev->use_terminator = 0;
163         if (!arg) {
164                 rev->commit_format = CMIT_FMT_DEFAULT;
165                 return;
166         }
167         if (skip_prefix(arg, "format:", &arg)) {
168                 save_user_format(rev, arg, 0);
169                 return;
170         }
171
172         if (!*arg || skip_prefix(arg, "tformat:", &arg) || strchr(arg, '%')) {
173                 save_user_format(rev, arg, 1);
174                 return;
175         }
176
177         commit_format = find_commit_format(arg);
178         if (!commit_format)
179                 die("invalid --pretty format: %s", arg);
180
181         rev->commit_format = commit_format->format;
182         rev->use_terminator = commit_format->is_tformat;
183         rev->expand_tabs_in_log_default = commit_format->expand_tabs_in_log;
184         if (commit_format->format == CMIT_FMT_USERFORMAT) {
185                 save_user_format(rev, commit_format->user_format,
186                                  commit_format->is_tformat);
187         }
188 }
189
190 /*
191  * Generic support for pretty-printing the header
192  */
193 static int get_one_line(const char *msg)
194 {
195         int ret = 0;
196
197         for (;;) {
198                 char c = *msg++;
199                 if (!c)
200                         break;
201                 ret++;
202                 if (c == '\n')
203                         break;
204         }
205         return ret;
206 }
207
208 /* High bit set, or ISO-2022-INT */
209 static int non_ascii(int ch)
210 {
211         return !isascii(ch) || ch == '\033';
212 }
213
214 int has_non_ascii(const char *s)
215 {
216         int ch;
217         if (!s)
218                 return 0;
219         while ((ch = *s++) != '\0') {
220                 if (non_ascii(ch))
221                         return 1;
222         }
223         return 0;
224 }
225
226 static int is_rfc822_special(char ch)
227 {
228         switch (ch) {
229         case '(':
230         case ')':
231         case '<':
232         case '>':
233         case '[':
234         case ']':
235         case ':':
236         case ';':
237         case '@':
238         case ',':
239         case '.':
240         case '"':
241         case '\\':
242                 return 1;
243         default:
244                 return 0;
245         }
246 }
247
248 static int needs_rfc822_quoting(const char *s, int len)
249 {
250         int i;
251         for (i = 0; i < len; i++)
252                 if (is_rfc822_special(s[i]))
253                         return 1;
254         return 0;
255 }
256
257 static int last_line_length(struct strbuf *sb)
258 {
259         int i;
260
261         /* How many bytes are already used on the last line? */
262         for (i = sb->len - 1; i >= 0; i--)
263                 if (sb->buf[i] == '\n')
264                         break;
265         return sb->len - (i + 1);
266 }
267
268 static void add_rfc822_quoted(struct strbuf *out, const char *s, int len)
269 {
270         int i;
271
272         /* just a guess, we may have to also backslash-quote */
273         strbuf_grow(out, len + 2);
274
275         strbuf_addch(out, '"');
276         for (i = 0; i < len; i++) {
277                 switch (s[i]) {
278                 case '"':
279                 case '\\':
280                         strbuf_addch(out, '\\');
281                         /* fall through */
282                 default:
283                         strbuf_addch(out, s[i]);
284                 }
285         }
286         strbuf_addch(out, '"');
287 }
288
289 enum rfc2047_type {
290         RFC2047_SUBJECT,
291         RFC2047_ADDRESS
292 };
293
294 static int is_rfc2047_special(char ch, enum rfc2047_type type)
295 {
296         /*
297          * rfc2047, section 4.2:
298          *
299          *    8-bit values which correspond to printable ASCII characters other
300          *    than "=", "?", and "_" (underscore), MAY be represented as those
301          *    characters.  (But see section 5 for restrictions.)  In
302          *    particular, SPACE and TAB MUST NOT be represented as themselves
303          *    within encoded words.
304          */
305
306         /*
307          * rule out non-ASCII characters and non-printable characters (the
308          * non-ASCII check should be redundant as isprint() is not localized
309          * and only knows about ASCII, but be defensive about that)
310          */
311         if (non_ascii(ch) || !isprint(ch))
312                 return 1;
313
314         /*
315          * rule out special printable characters (' ' should be the only
316          * whitespace character considered printable, but be defensive and use
317          * isspace())
318          */
319         if (isspace(ch) || ch == '=' || ch == '?' || ch == '_')
320                 return 1;
321
322         /*
323          * rfc2047, section 5.3:
324          *
325          *    As a replacement for a 'word' entity within a 'phrase', for example,
326          *    one that precedes an address in a From, To, or Cc header.  The ABNF
327          *    definition for 'phrase' from RFC 822 thus becomes:
328          *
329          *    phrase = 1*( encoded-word / word )
330          *
331          *    In this case the set of characters that may be used in a "Q"-encoded
332          *    'encoded-word' is restricted to: <upper and lower case ASCII
333          *    letters, decimal digits, "!", "*", "+", "-", "/", "=", and "_"
334          *    (underscore, ASCII 95.)>.  An 'encoded-word' that appears within a
335          *    'phrase' MUST be separated from any adjacent 'word', 'text' or
336          *    'special' by 'linear-white-space'.
337          */
338
339         if (type != RFC2047_ADDRESS)
340                 return 0;
341
342         /* '=' and '_' are special cases and have been checked above */
343         return !(isalnum(ch) || ch == '!' || ch == '*' || ch == '+' || ch == '-' || ch == '/');
344 }
345
346 static int needs_rfc2047_encoding(const char *line, int len)
347 {
348         int i;
349
350         for (i = 0; i < len; i++) {
351                 int ch = line[i];
352                 if (non_ascii(ch) || ch == '\n')
353                         return 1;
354                 if ((i + 1 < len) && (ch == '=' && line[i+1] == '?'))
355                         return 1;
356         }
357
358         return 0;
359 }
360
361 static void add_rfc2047(struct strbuf *sb, const char *line, size_t len,
362                        const char *encoding, enum rfc2047_type type)
363 {
364         static const int max_encoded_length = 76; /* per rfc2047 */
365         int i;
366         int line_len = last_line_length(sb);
367
368         strbuf_grow(sb, len * 3 + strlen(encoding) + 100);
369         strbuf_addf(sb, "=?%s?q?", encoding);
370         line_len += strlen(encoding) + 5; /* 5 for =??q? */
371
372         while (len) {
373                 /*
374                  * RFC 2047, section 5 (3):
375                  *
376                  * Each 'encoded-word' MUST represent an integral number of
377                  * characters.  A multi-octet character may not be split across
378                  * adjacent 'encoded- word's.
379                  */
380                 const unsigned char *p = (const unsigned char *)line;
381                 int chrlen = mbs_chrlen(&line, &len, encoding);
382                 int is_special = (chrlen > 1) || is_rfc2047_special(*p, type);
383
384                 /* "=%02X" * chrlen, or the byte itself */
385                 const char *encoded_fmt = is_special ? "=%02X"    : "%c";
386                 int         encoded_len = is_special ? 3 * chrlen : 1;
387
388                 /*
389                  * According to RFC 2047, we could encode the special character
390                  * ' ' (space) with '_' (underscore) for readability. But many
391                  * programs do not understand this and just leave the
392                  * underscore in place. Thus, we do nothing special here, which
393                  * causes ' ' to be encoded as '=20', avoiding this problem.
394                  */
395
396                 if (line_len + encoded_len + 2 > max_encoded_length) {
397                         /* It won't fit with trailing "?=" --- break the line */
398                         strbuf_addf(sb, "?=\n =?%s?q?", encoding);
399                         line_len = strlen(encoding) + 5 + 1; /* =??q? plus SP */
400                 }
401
402                 for (i = 0; i < chrlen; i++)
403                         strbuf_addf(sb, encoded_fmt, p[i]);
404                 line_len += encoded_len;
405         }
406         strbuf_addstr(sb, "?=");
407 }
408
409 const char *show_ident_date(const struct ident_split *ident,
410                             const struct date_mode *mode)
411 {
412         timestamp_t date = 0;
413         long tz = 0;
414
415         if (ident->date_begin && ident->date_end)
416                 date = parse_timestamp(ident->date_begin, NULL, 10);
417         if (date_overflows(date))
418                 date = 0;
419         else {
420                 if (ident->tz_begin && ident->tz_end)
421                         tz = strtol(ident->tz_begin, NULL, 10);
422                 if (tz >= INT_MAX || tz <= INT_MIN)
423                         tz = 0;
424         }
425         return show_date(date, tz, mode);
426 }
427
428 void pp_user_info(struct pretty_print_context *pp,
429                   const char *what, struct strbuf *sb,
430                   const char *line, const char *encoding)
431 {
432         struct ident_split ident;
433         char *line_end;
434         const char *mailbuf, *namebuf;
435         size_t namelen, maillen;
436         int max_length = 78; /* per rfc2822 */
437
438         if (pp->fmt == CMIT_FMT_ONELINE)
439                 return;
440
441         line_end = strchrnul(line, '\n');
442         if (split_ident_line(&ident, line, line_end - line))
443                 return;
444
445         mailbuf = ident.mail_begin;
446         maillen = ident.mail_end - ident.mail_begin;
447         namebuf = ident.name_begin;
448         namelen = ident.name_end - ident.name_begin;
449
450         if (pp->mailmap)
451                 map_user(pp->mailmap, &mailbuf, &maillen, &namebuf, &namelen);
452
453         if (cmit_fmt_is_mail(pp->fmt)) {
454                 if (pp->from_ident && ident_cmp(pp->from_ident, &ident)) {
455                         struct strbuf buf = STRBUF_INIT;
456
457                         strbuf_addstr(&buf, "From: ");
458                         strbuf_add(&buf, namebuf, namelen);
459                         strbuf_addstr(&buf, " <");
460                         strbuf_add(&buf, mailbuf, maillen);
461                         strbuf_addstr(&buf, ">\n");
462                         string_list_append(&pp->in_body_headers,
463                                            strbuf_detach(&buf, NULL));
464
465                         mailbuf = pp->from_ident->mail_begin;
466                         maillen = pp->from_ident->mail_end - mailbuf;
467                         namebuf = pp->from_ident->name_begin;
468                         namelen = pp->from_ident->name_end - namebuf;
469                 }
470
471                 strbuf_addstr(sb, "From: ");
472                 if (needs_rfc2047_encoding(namebuf, namelen)) {
473                         add_rfc2047(sb, namebuf, namelen,
474                                     encoding, RFC2047_ADDRESS);
475                         max_length = 76; /* per rfc2047 */
476                 } else if (needs_rfc822_quoting(namebuf, namelen)) {
477                         struct strbuf quoted = STRBUF_INIT;
478                         add_rfc822_quoted(&quoted, namebuf, namelen);
479                         strbuf_add_wrapped_bytes(sb, quoted.buf, quoted.len,
480                                                         -6, 1, max_length);
481                         strbuf_release(&quoted);
482                 } else {
483                         strbuf_add_wrapped_bytes(sb, namebuf, namelen,
484                                                  -6, 1, max_length);
485                 }
486
487                 if (max_length <
488                     last_line_length(sb) + strlen(" <") + maillen + strlen(">"))
489                         strbuf_addch(sb, '\n');
490                 strbuf_addf(sb, " <%.*s>\n", (int)maillen, mailbuf);
491         } else {
492                 strbuf_addf(sb, "%s: %.*s%.*s <%.*s>\n", what,
493                             (pp->fmt == CMIT_FMT_FULLER) ? 4 : 0, "    ",
494                             (int)namelen, namebuf, (int)maillen, mailbuf);
495         }
496
497         switch (pp->fmt) {
498         case CMIT_FMT_MEDIUM:
499                 strbuf_addf(sb, "Date:   %s\n",
500                             show_ident_date(&ident, &pp->date_mode));
501                 break;
502         case CMIT_FMT_EMAIL:
503         case CMIT_FMT_MBOXRD:
504                 strbuf_addf(sb, "Date: %s\n",
505                             show_ident_date(&ident, DATE_MODE(RFC2822)));
506                 break;
507         case CMIT_FMT_FULLER:
508                 strbuf_addf(sb, "%sDate: %s\n", what,
509                             show_ident_date(&ident, &pp->date_mode));
510                 break;
511         default:
512                 /* notin' */
513                 break;
514         }
515 }
516
517 static int is_blank_line(const char *line, int *len_p)
518 {
519         int len = *len_p;
520         while (len && isspace(line[len - 1]))
521                 len--;
522         *len_p = len;
523         return !len;
524 }
525
526 const char *skip_blank_lines(const char *msg)
527 {
528         for (;;) {
529                 int linelen = get_one_line(msg);
530                 int ll = linelen;
531                 if (!linelen)
532                         break;
533                 if (!is_blank_line(msg, &ll))
534                         break;
535                 msg += linelen;
536         }
537         return msg;
538 }
539
540 static void add_merge_info(const struct pretty_print_context *pp,
541                            struct strbuf *sb, const struct commit *commit)
542 {
543         struct commit_list *parent = commit->parents;
544
545         if ((pp->fmt == CMIT_FMT_ONELINE) || (cmit_fmt_is_mail(pp->fmt)) ||
546             !parent || !parent->next)
547                 return;
548
549         strbuf_addstr(sb, "Merge:");
550
551         while (parent) {
552                 struct object_id *oidp = &parent->item->object.oid;
553                 strbuf_addch(sb, ' ');
554                 if (pp->abbrev)
555                         strbuf_add_unique_abbrev(sb, oidp, pp->abbrev);
556                 else
557                         strbuf_addstr(sb, oid_to_hex(oidp));
558                 parent = parent->next;
559         }
560         strbuf_addch(sb, '\n');
561 }
562
563 static char *get_header(const char *msg, const char *key)
564 {
565         size_t len;
566         const char *v = find_commit_header(msg, key, &len);
567         return v ? xmemdupz(v, len) : NULL;
568 }
569
570 static char *replace_encoding_header(char *buf, const char *encoding)
571 {
572         struct strbuf tmp = STRBUF_INIT;
573         size_t start, len;
574         char *cp = buf;
575
576         /* guess if there is an encoding header before a \n\n */
577         while (!starts_with(cp, "encoding ")) {
578                 cp = strchr(cp, '\n');
579                 if (!cp || *++cp == '\n')
580                         return buf;
581         }
582         start = cp - buf;
583         cp = strchr(cp, '\n');
584         if (!cp)
585                 return buf; /* should not happen but be defensive */
586         len = cp + 1 - (buf + start);
587
588         strbuf_attach(&tmp, buf, strlen(buf), strlen(buf) + 1);
589         if (is_encoding_utf8(encoding)) {
590                 /* we have re-coded to UTF-8; drop the header */
591                 strbuf_remove(&tmp, start, len);
592         } else {
593                 /* just replaces XXXX in 'encoding XXXX\n' */
594                 strbuf_splice(&tmp, start + strlen("encoding "),
595                                           len - strlen("encoding \n"),
596                                           encoding, strlen(encoding));
597         }
598         return strbuf_detach(&tmp, NULL);
599 }
600
601 const char *repo_logmsg_reencode(struct repository *r,
602                                  const struct commit *commit,
603                                  char **commit_encoding,
604                                  const char *output_encoding)
605 {
606         static const char *utf8 = "UTF-8";
607         const char *use_encoding;
608         char *encoding;
609         const char *msg = repo_get_commit_buffer(r, commit, NULL);
610         char *out;
611
612         if (!output_encoding || !*output_encoding) {
613                 if (commit_encoding)
614                         *commit_encoding = get_header(msg, "encoding");
615                 return msg;
616         }
617         encoding = get_header(msg, "encoding");
618         if (commit_encoding)
619                 *commit_encoding = encoding;
620         use_encoding = encoding ? encoding : utf8;
621         if (same_encoding(use_encoding, output_encoding)) {
622                 /*
623                  * No encoding work to be done. If we have no encoding header
624                  * at all, then there's nothing to do, and we can return the
625                  * message verbatim (whether newly allocated or not).
626                  */
627                 if (!encoding)
628                         return msg;
629
630                 /*
631                  * Otherwise, we still want to munge the encoding header in the
632                  * result, which will be done by modifying the buffer. If we
633                  * are using a fresh copy, we can reuse it. But if we are using
634                  * the cached copy from get_commit_buffer, we need to duplicate it
635                  * to avoid munging the cached copy.
636                  */
637                 if (msg == get_cached_commit_buffer(r, commit, NULL))
638                         out = xstrdup(msg);
639                 else
640                         out = (char *)msg;
641         }
642         else {
643                 /*
644                  * There's actual encoding work to do. Do the reencoding, which
645                  * still leaves the header to be replaced in the next step. At
646                  * this point, we are done with msg. If we allocated a fresh
647                  * copy, we can free it.
648                  */
649                 out = reencode_string(msg, output_encoding, use_encoding);
650                 if (out)
651                         repo_unuse_commit_buffer(r, commit, msg);
652         }
653
654         /*
655          * This replacement actually consumes the buffer we hand it, so we do
656          * not have to worry about freeing the old "out" here.
657          */
658         if (out)
659                 out = replace_encoding_header(out, output_encoding);
660
661         if (!commit_encoding)
662                 free(encoding);
663         /*
664          * If the re-encoding failed, out might be NULL here; in that
665          * case we just return the commit message verbatim.
666          */
667         return out ? out : msg;
668 }
669
670 static int mailmap_name(const char **email, size_t *email_len,
671                         const char **name, size_t *name_len)
672 {
673         static struct string_list *mail_map;
674         if (!mail_map) {
675                 mail_map = xcalloc(1, sizeof(*mail_map));
676                 read_mailmap(mail_map, NULL);
677         }
678         return mail_map->nr && map_user(mail_map, email, email_len, name, name_len);
679 }
680
681 static size_t format_person_part(struct strbuf *sb, char part,
682                                  const char *msg, int len,
683                                  const struct date_mode *dmode)
684 {
685         /* currently all placeholders have same length */
686         const int placeholder_len = 2;
687         struct ident_split s;
688         const char *name, *mail;
689         size_t maillen, namelen;
690
691         if (split_ident_line(&s, msg, len) < 0)
692                 goto skip;
693
694         name = s.name_begin;
695         namelen = s.name_end - s.name_begin;
696         mail = s.mail_begin;
697         maillen = s.mail_end - s.mail_begin;
698
699         if (part == 'N' || part == 'E' || part == 'L') /* mailmap lookup */
700                 mailmap_name(&mail, &maillen, &name, &namelen);
701         if (part == 'n' || part == 'N') {       /* name */
702                 strbuf_add(sb, name, namelen);
703                 return placeholder_len;
704         }
705         if (part == 'e' || part == 'E') {       /* email */
706                 strbuf_add(sb, mail, maillen);
707                 return placeholder_len;
708         }
709         if (part == 'l' || part == 'L') {       /* local-part */
710                 const char *at = memchr(mail, '@', maillen);
711                 if (at)
712                         maillen = at - mail;
713                 strbuf_add(sb, mail, maillen);
714                 return placeholder_len;
715         }
716
717         if (!s.date_begin)
718                 goto skip;
719
720         if (part == 't') {      /* date, UNIX timestamp */
721                 strbuf_add(sb, s.date_begin, s.date_end - s.date_begin);
722                 return placeholder_len;
723         }
724
725         switch (part) {
726         case 'd':       /* date */
727                 strbuf_addstr(sb, show_ident_date(&s, dmode));
728                 return placeholder_len;
729         case 'D':       /* date, RFC2822 style */
730                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(RFC2822)));
731                 return placeholder_len;
732         case 'r':       /* date, relative */
733                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(RELATIVE)));
734                 return placeholder_len;
735         case 'i':       /* date, ISO 8601-like */
736                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(ISO8601)));
737                 return placeholder_len;
738         case 'I':       /* date, ISO 8601 strict */
739                 strbuf_addstr(sb, show_ident_date(&s, DATE_MODE(ISO8601_STRICT)));
740                 return placeholder_len;
741         }
742
743 skip:
744         /*
745          * reading from either a bogus commit, or a reflog entry with
746          * %gn, %ge, etc.; 'sb' cannot be updated, but we still need
747          * to compute a valid return value.
748          */
749         if (part == 'n' || part == 'e' || part == 't' || part == 'd'
750             || part == 'D' || part == 'r' || part == 'i')
751                 return placeholder_len;
752
753         return 0; /* unknown placeholder */
754 }
755
756 struct chunk {
757         size_t off;
758         size_t len;
759 };
760
761 enum flush_type {
762         no_flush,
763         flush_right,
764         flush_left,
765         flush_left_and_steal,
766         flush_both
767 };
768
769 enum trunc_type {
770         trunc_none,
771         trunc_left,
772         trunc_middle,
773         trunc_right
774 };
775
776 struct format_commit_context {
777         const struct commit *commit;
778         const struct pretty_print_context *pretty_ctx;
779         unsigned commit_header_parsed:1;
780         unsigned commit_message_parsed:1;
781         struct signature_check signature_check;
782         enum flush_type flush_type;
783         enum trunc_type truncate;
784         const char *message;
785         char *commit_encoding;
786         size_t width, indent1, indent2;
787         int auto_color;
788         int padding;
789
790         /* These offsets are relative to the start of the commit message. */
791         struct chunk author;
792         struct chunk committer;
793         size_t message_off;
794         size_t subject_off;
795         size_t body_off;
796
797         /* The following ones are relative to the result struct strbuf. */
798         size_t wrap_start;
799 };
800
801 static void parse_commit_header(struct format_commit_context *context)
802 {
803         const char *msg = context->message;
804         int i;
805
806         for (i = 0; msg[i]; i++) {
807                 const char *name;
808                 int eol;
809                 for (eol = i; msg[eol] && msg[eol] != '\n'; eol++)
810                         ; /* do nothing */
811
812                 if (i == eol) {
813                         break;
814                 } else if (skip_prefix(msg + i, "author ", &name)) {
815                         context->author.off = name - msg;
816                         context->author.len = msg + eol - name;
817                 } else if (skip_prefix(msg + i, "committer ", &name)) {
818                         context->committer.off = name - msg;
819                         context->committer.len = msg + eol - name;
820                 }
821                 i = eol;
822         }
823         context->message_off = i;
824         context->commit_header_parsed = 1;
825 }
826
827 static int istitlechar(char c)
828 {
829         return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
830                 (c >= '0' && c <= '9') || c == '.' || c == '_';
831 }
832
833 static void format_sanitized_subject(struct strbuf *sb, const char *msg)
834 {
835         size_t trimlen;
836         size_t start_len = sb->len;
837         int space = 2;
838
839         for (; *msg && *msg != '\n'; msg++) {
840                 if (istitlechar(*msg)) {
841                         if (space == 1)
842                                 strbuf_addch(sb, '-');
843                         space = 0;
844                         strbuf_addch(sb, *msg);
845                         if (*msg == '.')
846                                 while (*(msg+1) == '.')
847                                         msg++;
848                 } else
849                         space |= 1;
850         }
851
852         /* trim any trailing '.' or '-' characters */
853         trimlen = 0;
854         while (sb->len - trimlen > start_len &&
855                 (sb->buf[sb->len - 1 - trimlen] == '.'
856                 || sb->buf[sb->len - 1 - trimlen] == '-'))
857                 trimlen++;
858         strbuf_remove(sb, sb->len - trimlen, trimlen);
859 }
860
861 const char *format_subject(struct strbuf *sb, const char *msg,
862                            const char *line_separator)
863 {
864         int first = 1;
865
866         for (;;) {
867                 const char *line = msg;
868                 int linelen = get_one_line(line);
869
870                 msg += linelen;
871                 if (!linelen || is_blank_line(line, &linelen))
872                         break;
873
874                 if (!sb)
875                         continue;
876                 strbuf_grow(sb, linelen + 2);
877                 if (!first)
878                         strbuf_addstr(sb, line_separator);
879                 strbuf_add(sb, line, linelen);
880                 first = 0;
881         }
882         return msg;
883 }
884
885 static void parse_commit_message(struct format_commit_context *c)
886 {
887         const char *msg = c->message + c->message_off;
888         const char *start = c->message;
889
890         msg = skip_blank_lines(msg);
891         c->subject_off = msg - start;
892
893         msg = format_subject(NULL, msg, NULL);
894         msg = skip_blank_lines(msg);
895         c->body_off = msg - start;
896
897         c->commit_message_parsed = 1;
898 }
899
900 static void strbuf_wrap(struct strbuf *sb, size_t pos,
901                         size_t width, size_t indent1, size_t indent2)
902 {
903         struct strbuf tmp = STRBUF_INIT;
904
905         if (pos)
906                 strbuf_add(&tmp, sb->buf, pos);
907         strbuf_add_wrapped_text(&tmp, sb->buf + pos,
908                                 (int) indent1, (int) indent2, (int) width);
909         strbuf_swap(&tmp, sb);
910         strbuf_release(&tmp);
911 }
912
913 static void rewrap_message_tail(struct strbuf *sb,
914                                 struct format_commit_context *c,
915                                 size_t new_width, size_t new_indent1,
916                                 size_t new_indent2)
917 {
918         if (c->width == new_width && c->indent1 == new_indent1 &&
919             c->indent2 == new_indent2)
920                 return;
921         if (c->wrap_start < sb->len)
922                 strbuf_wrap(sb, c->wrap_start, c->width, c->indent1, c->indent2);
923         c->wrap_start = sb->len;
924         c->width = new_width;
925         c->indent1 = new_indent1;
926         c->indent2 = new_indent2;
927 }
928
929 static int format_reflog_person(struct strbuf *sb,
930                                 char part,
931                                 struct reflog_walk_info *log,
932                                 const struct date_mode *dmode)
933 {
934         const char *ident;
935
936         if (!log)
937                 return 2;
938
939         ident = get_reflog_ident(log);
940         if (!ident)
941                 return 2;
942
943         return format_person_part(sb, part, ident, strlen(ident), dmode);
944 }
945
946 static size_t parse_color(struct strbuf *sb, /* in UTF-8 */
947                           const char *placeholder,
948                           struct format_commit_context *c)
949 {
950         const char *rest = placeholder;
951         const char *basic_color = NULL;
952
953         if (placeholder[1] == '(') {
954                 const char *begin = placeholder + 2;
955                 const char *end = strchr(begin, ')');
956                 char color[COLOR_MAXLEN];
957
958                 if (!end)
959                         return 0;
960
961                 if (skip_prefix(begin, "auto,", &begin)) {
962                         if (!want_color(c->pretty_ctx->color))
963                                 return end - placeholder + 1;
964                 } else if (skip_prefix(begin, "always,", &begin)) {
965                         /* nothing to do; we do not respect want_color at all */
966                 } else {
967                         /* the default is the same as "auto" */
968                         if (!want_color(c->pretty_ctx->color))
969                                 return end - placeholder + 1;
970                 }
971
972                 if (color_parse_mem(begin, end - begin, color) < 0)
973                         die(_("unable to parse --pretty format"));
974                 strbuf_addstr(sb, color);
975                 return end - placeholder + 1;
976         }
977
978         /*
979          * We handle things like "%C(red)" above; for historical reasons, there
980          * are a few colors that can be specified without parentheses (and
981          * they cannot support things like "auto" or "always" at all).
982          */
983         if (skip_prefix(placeholder + 1, "red", &rest))
984                 basic_color = GIT_COLOR_RED;
985         else if (skip_prefix(placeholder + 1, "green", &rest))
986                 basic_color = GIT_COLOR_GREEN;
987         else if (skip_prefix(placeholder + 1, "blue", &rest))
988                 basic_color = GIT_COLOR_BLUE;
989         else if (skip_prefix(placeholder + 1, "reset", &rest))
990                 basic_color = GIT_COLOR_RESET;
991
992         if (basic_color && want_color(c->pretty_ctx->color))
993                 strbuf_addstr(sb, basic_color);
994
995         return rest - placeholder;
996 }
997
998 static size_t parse_padding_placeholder(const char *placeholder,
999                                         struct format_commit_context *c)
1000 {
1001         const char *ch = placeholder;
1002         enum flush_type flush_type;
1003         int to_column = 0;
1004
1005         switch (*ch++) {
1006         case '<':
1007                 flush_type = flush_right;
1008                 break;
1009         case '>':
1010                 if (*ch == '<') {
1011                         flush_type = flush_both;
1012                         ch++;
1013                 } else if (*ch == '>') {
1014                         flush_type = flush_left_and_steal;
1015                         ch++;
1016                 } else
1017                         flush_type = flush_left;
1018                 break;
1019         default:
1020                 return 0;
1021         }
1022
1023         /* the next value means "wide enough to that column" */
1024         if (*ch == '|') {
1025                 to_column = 1;
1026                 ch++;
1027         }
1028
1029         if (*ch == '(') {
1030                 const char *start = ch + 1;
1031                 const char *end = start + strcspn(start, ",)");
1032                 char *next;
1033                 int width;
1034                 if (!end || end == start)
1035                         return 0;
1036                 width = strtol(start, &next, 10);
1037                 if (next == start || width == 0)
1038                         return 0;
1039                 if (width < 0) {
1040                         if (to_column)
1041                                 width += term_columns();
1042                         if (width < 0)
1043                                 return 0;
1044                 }
1045                 c->padding = to_column ? -width : width;
1046                 c->flush_type = flush_type;
1047
1048                 if (*end == ',') {
1049                         start = end + 1;
1050                         end = strchr(start, ')');
1051                         if (!end || end == start)
1052                                 return 0;
1053                         if (starts_with(start, "trunc)"))
1054                                 c->truncate = trunc_right;
1055                         else if (starts_with(start, "ltrunc)"))
1056                                 c->truncate = trunc_left;
1057                         else if (starts_with(start, "mtrunc)"))
1058                                 c->truncate = trunc_middle;
1059                         else
1060                                 return 0;
1061                 } else
1062                         c->truncate = trunc_none;
1063
1064                 return end - placeholder + 1;
1065         }
1066         return 0;
1067 }
1068
1069 static int match_placeholder_arg_value(const char *to_parse, const char *candidate,
1070                                        const char **end, const char **valuestart,
1071                                        size_t *valuelen)
1072 {
1073         const char *p;
1074
1075         if (!(skip_prefix(to_parse, candidate, &p)))
1076                 return 0;
1077         if (valuestart) {
1078                 if (*p == '=') {
1079                         *valuestart = p + 1;
1080                         *valuelen = strcspn(*valuestart, ",)");
1081                         p = *valuestart + *valuelen;
1082                 } else {
1083                         if (*p != ',' && *p != ')')
1084                                 return 0;
1085                         *valuestart = NULL;
1086                         *valuelen = 0;
1087                 }
1088         }
1089         if (*p == ',') {
1090                 *end = p + 1;
1091                 return 1;
1092         }
1093         if (*p == ')') {
1094                 *end = p;
1095                 return 1;
1096         }
1097         return 0;
1098 }
1099
1100 static int match_placeholder_bool_arg(const char *to_parse, const char *candidate,
1101                                       const char **end, int *val)
1102 {
1103         const char *argval;
1104         char *strval;
1105         size_t arglen;
1106         int v;
1107
1108         if (!match_placeholder_arg_value(to_parse, candidate, end, &argval, &arglen))
1109                 return 0;
1110
1111         if (!argval) {
1112                 *val = 1;
1113                 return 1;
1114         }
1115
1116         strval = xstrndup(argval, arglen);
1117         v = git_parse_maybe_bool(strval);
1118         free(strval);
1119
1120         if (v == -1)
1121                 return 0;
1122
1123         *val = v;
1124
1125         return 1;
1126 }
1127
1128 static int format_trailer_match_cb(const struct strbuf *key, void *ud)
1129 {
1130         const struct string_list *list = ud;
1131         const struct string_list_item *item;
1132
1133         for_each_string_list_item (item, list) {
1134                 if (key->len == (uintptr_t)item->util &&
1135                     !strncasecmp(item->string, key->buf, key->len))
1136                         return 1;
1137         }
1138         return 0;
1139 }
1140
1141 static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
1142                                 const char *placeholder,
1143                                 void *context)
1144 {
1145         struct format_commit_context *c = context;
1146         const struct commit *commit = c->commit;
1147         const char *msg = c->message;
1148         struct commit_list *p;
1149         const char *arg;
1150         size_t res;
1151         char **slot;
1152
1153         /* these are independent of the commit */
1154         res = strbuf_expand_literal_cb(sb, placeholder, NULL);
1155         if (res)
1156                 return res;
1157
1158         switch (placeholder[0]) {
1159         case 'C':
1160                 if (starts_with(placeholder + 1, "(auto)")) {
1161                         c->auto_color = want_color(c->pretty_ctx->color);
1162                         if (c->auto_color && sb->len)
1163                                 strbuf_addstr(sb, GIT_COLOR_RESET);
1164                         return 7; /* consumed 7 bytes, "C(auto)" */
1165                 } else {
1166                         int ret = parse_color(sb, placeholder, c);
1167                         if (ret)
1168                                 c->auto_color = 0;
1169                         /*
1170                          * Otherwise, we decided to treat %C<unknown>
1171                          * as a literal string, and the previous
1172                          * %C(auto) is still valid.
1173                          */
1174                         return ret;
1175                 }
1176         case 'w':
1177                 if (placeholder[1] == '(') {
1178                         unsigned long width = 0, indent1 = 0, indent2 = 0;
1179                         char *next;
1180                         const char *start = placeholder + 2;
1181                         const char *end = strchr(start, ')');
1182                         if (!end)
1183                                 return 0;
1184                         if (end > start) {
1185                                 width = strtoul(start, &next, 10);
1186                                 if (*next == ',') {
1187                                         indent1 = strtoul(next + 1, &next, 10);
1188                                         if (*next == ',') {
1189                                                 indent2 = strtoul(next + 1,
1190                                                                  &next, 10);
1191                                         }
1192                                 }
1193                                 if (*next != ')')
1194                                         return 0;
1195                         }
1196                         rewrap_message_tail(sb, c, width, indent1, indent2);
1197                         return end - placeholder + 1;
1198                 } else
1199                         return 0;
1200
1201         case '<':
1202         case '>':
1203                 return parse_padding_placeholder(placeholder, c);
1204         }
1205
1206         /* these depend on the commit */
1207         if (!commit->object.parsed)
1208                 parse_object(the_repository, &commit->object.oid);
1209
1210         switch (placeholder[0]) {
1211         case 'H':               /* commit hash */
1212                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_COMMIT));
1213                 strbuf_addstr(sb, oid_to_hex(&commit->object.oid));
1214                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_RESET));
1215                 return 1;
1216         case 'h':               /* abbreviated commit hash */
1217                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_COMMIT));
1218                 strbuf_add_unique_abbrev(sb, &commit->object.oid,
1219                                          c->pretty_ctx->abbrev);
1220                 strbuf_addstr(sb, diff_get_color(c->auto_color, DIFF_RESET));
1221                 return 1;
1222         case 'T':               /* tree hash */
1223                 strbuf_addstr(sb, oid_to_hex(get_commit_tree_oid(commit)));
1224                 return 1;
1225         case 't':               /* abbreviated tree hash */
1226                 strbuf_add_unique_abbrev(sb,
1227                                          get_commit_tree_oid(commit),
1228                                          c->pretty_ctx->abbrev);
1229                 return 1;
1230         case 'P':               /* parent hashes */
1231                 for (p = commit->parents; p; p = p->next) {
1232                         if (p != commit->parents)
1233                                 strbuf_addch(sb, ' ');
1234                         strbuf_addstr(sb, oid_to_hex(&p->item->object.oid));
1235                 }
1236                 return 1;
1237         case 'p':               /* abbreviated parent hashes */
1238                 for (p = commit->parents; p; p = p->next) {
1239                         if (p != commit->parents)
1240                                 strbuf_addch(sb, ' ');
1241                         strbuf_add_unique_abbrev(sb, &p->item->object.oid,
1242                                                  c->pretty_ctx->abbrev);
1243                 }
1244                 return 1;
1245         case 'm':               /* left/right/bottom */
1246                 strbuf_addstr(sb, get_revision_mark(NULL, commit));
1247                 return 1;
1248         case 'd':
1249                 format_decorations(sb, commit, c->auto_color);
1250                 return 1;
1251         case 'D':
1252                 format_decorations_extended(sb, commit, c->auto_color, "", ", ", "");
1253                 return 1;
1254         case 'S':               /* tag/branch like --source */
1255                 if (!(c->pretty_ctx->rev && c->pretty_ctx->rev->sources))
1256                         return 0;
1257                 slot = revision_sources_at(c->pretty_ctx->rev->sources, commit);
1258                 if (!(slot && *slot))
1259                         return 0;
1260                 strbuf_addstr(sb, *slot);
1261                 return 1;
1262         case 'g':               /* reflog info */
1263                 switch(placeholder[1]) {
1264                 case 'd':       /* reflog selector */
1265                 case 'D':
1266                         if (c->pretty_ctx->reflog_info)
1267                                 get_reflog_selector(sb,
1268                                                     c->pretty_ctx->reflog_info,
1269                                                     &c->pretty_ctx->date_mode,
1270                                                     c->pretty_ctx->date_mode_explicit,
1271                                                     (placeholder[1] == 'd'));
1272                         return 2;
1273                 case 's':       /* reflog message */
1274                         if (c->pretty_ctx->reflog_info)
1275                                 get_reflog_message(sb, c->pretty_ctx->reflog_info);
1276                         return 2;
1277                 case 'n':
1278                 case 'N':
1279                 case 'e':
1280                 case 'E':
1281                         return format_reflog_person(sb,
1282                                                     placeholder[1],
1283                                                     c->pretty_ctx->reflog_info,
1284                                                     &c->pretty_ctx->date_mode);
1285                 }
1286                 return 0;       /* unknown %g placeholder */
1287         case 'N':
1288                 if (c->pretty_ctx->notes_message) {
1289                         strbuf_addstr(sb, c->pretty_ctx->notes_message);
1290                         return 1;
1291                 }
1292                 return 0;
1293         }
1294
1295         if (placeholder[0] == 'G') {
1296                 if (!c->signature_check.result)
1297                         check_commit_signature(c->commit, &(c->signature_check));
1298                 switch (placeholder[1]) {
1299                 case 'G':
1300                         if (c->signature_check.gpg_output)
1301                                 strbuf_addstr(sb, c->signature_check.gpg_output);
1302                         break;
1303                 case '?':
1304                         switch (c->signature_check.result) {
1305                         case 'G':
1306                         case 'B':
1307                         case 'E':
1308                         case 'U':
1309                         case 'N':
1310                         case 'X':
1311                         case 'Y':
1312                         case 'R':
1313                                 strbuf_addch(sb, c->signature_check.result);
1314                         }
1315                         break;
1316                 case 'S':
1317                         if (c->signature_check.signer)
1318                                 strbuf_addstr(sb, c->signature_check.signer);
1319                         break;
1320                 case 'K':
1321                         if (c->signature_check.key)
1322                                 strbuf_addstr(sb, c->signature_check.key);
1323                         break;
1324                 case 'F':
1325                         if (c->signature_check.fingerprint)
1326                                 strbuf_addstr(sb, c->signature_check.fingerprint);
1327                         break;
1328                 case 'P':
1329                         if (c->signature_check.primary_key_fingerprint)
1330                                 strbuf_addstr(sb, c->signature_check.primary_key_fingerprint);
1331                         break;
1332                 default:
1333                         return 0;
1334                 }
1335                 return 2;
1336         }
1337
1338
1339         /* For the rest we have to parse the commit header. */
1340         if (!c->commit_header_parsed)
1341                 parse_commit_header(c);
1342
1343         switch (placeholder[0]) {
1344         case 'a':       /* author ... */
1345                 return format_person_part(sb, placeholder[1],
1346                                    msg + c->author.off, c->author.len,
1347                                    &c->pretty_ctx->date_mode);
1348         case 'c':       /* committer ... */
1349                 return format_person_part(sb, placeholder[1],
1350                                    msg + c->committer.off, c->committer.len,
1351                                    &c->pretty_ctx->date_mode);
1352         case 'e':       /* encoding */
1353                 if (c->commit_encoding)
1354                         strbuf_addstr(sb, c->commit_encoding);
1355                 return 1;
1356         case 'B':       /* raw body */
1357                 /* message_off is always left at the initial newline */
1358                 strbuf_addstr(sb, msg + c->message_off + 1);
1359                 return 1;
1360         }
1361
1362         /* Now we need to parse the commit message. */
1363         if (!c->commit_message_parsed)
1364                 parse_commit_message(c);
1365
1366         switch (placeholder[0]) {
1367         case 's':       /* subject */
1368                 format_subject(sb, msg + c->subject_off, " ");
1369                 return 1;
1370         case 'f':       /* sanitized subject */
1371                 format_sanitized_subject(sb, msg + c->subject_off);
1372                 return 1;
1373         case 'b':       /* body */
1374                 strbuf_addstr(sb, msg + c->body_off);
1375                 return 1;
1376         }
1377
1378         if (skip_prefix(placeholder, "(trailers", &arg)) {
1379                 struct process_trailer_options opts = PROCESS_TRAILER_OPTIONS_INIT;
1380                 struct string_list filter_list = STRING_LIST_INIT_NODUP;
1381                 struct strbuf sepbuf = STRBUF_INIT;
1382                 size_t ret = 0;
1383
1384                 opts.no_divider = 1;
1385
1386                 if (*arg == ':') {
1387                         arg++;
1388                         for (;;) {
1389                                 const char *argval;
1390                                 size_t arglen;
1391
1392                                 if (match_placeholder_arg_value(arg, "key", &arg, &argval, &arglen)) {
1393                                         uintptr_t len = arglen;
1394
1395                                         if (!argval)
1396                                                 goto trailer_out;
1397
1398                                         if (len && argval[len - 1] == ':')
1399                                                 len--;
1400                                         string_list_append(&filter_list, argval)->util = (char *)len;
1401
1402                                         opts.filter = format_trailer_match_cb;
1403                                         opts.filter_data = &filter_list;
1404                                         opts.only_trailers = 1;
1405                                 } else if (match_placeholder_arg_value(arg, "separator", &arg, &argval, &arglen)) {
1406                                         char *fmt;
1407
1408                                         strbuf_reset(&sepbuf);
1409                                         fmt = xstrndup(argval, arglen);
1410                                         strbuf_expand(&sepbuf, fmt, strbuf_expand_literal_cb, NULL);
1411                                         free(fmt);
1412                                         opts.separator = &sepbuf;
1413                                 } else if (!match_placeholder_bool_arg(arg, "only", &arg, &opts.only_trailers) &&
1414                                            !match_placeholder_bool_arg(arg, "unfold", &arg, &opts.unfold) &&
1415                                            !match_placeholder_bool_arg(arg, "valueonly", &arg, &opts.value_only))
1416                                         break;
1417                         }
1418                 }
1419                 if (*arg == ')') {
1420                         format_trailers_from_commit(sb, msg + c->subject_off, &opts);
1421                         ret = arg - placeholder + 1;
1422                 }
1423         trailer_out:
1424                 string_list_clear(&filter_list, 0);
1425                 strbuf_release(&sepbuf);
1426                 return ret;
1427         }
1428
1429         return 0;       /* unknown placeholder */
1430 }
1431
1432 static size_t format_and_pad_commit(struct strbuf *sb, /* in UTF-8 */
1433                                     const char *placeholder,
1434                                     struct format_commit_context *c)
1435 {
1436         struct strbuf local_sb = STRBUF_INIT;
1437         int total_consumed = 0, len, padding = c->padding;
1438         if (padding < 0) {
1439                 const char *start = strrchr(sb->buf, '\n');
1440                 int occupied;
1441                 if (!start)
1442                         start = sb->buf;
1443                 occupied = utf8_strnwidth(start, -1, 1);
1444                 occupied += c->pretty_ctx->graph_width;
1445                 padding = (-padding) - occupied;
1446         }
1447         while (1) {
1448                 int modifier = *placeholder == 'C';
1449                 int consumed = format_commit_one(&local_sb, placeholder, c);
1450                 total_consumed += consumed;
1451
1452                 if (!modifier)
1453                         break;
1454
1455                 placeholder += consumed;
1456                 if (*placeholder != '%')
1457                         break;
1458                 placeholder++;
1459                 total_consumed++;
1460         }
1461         len = utf8_strnwidth(local_sb.buf, -1, 1);
1462
1463         if (c->flush_type == flush_left_and_steal) {
1464                 const char *ch = sb->buf + sb->len - 1;
1465                 while (len > padding && ch > sb->buf) {
1466                         const char *p;
1467                         if (*ch == ' ') {
1468                                 ch--;
1469                                 padding++;
1470                                 continue;
1471                         }
1472                         /* check for trailing ansi sequences */
1473                         if (*ch != 'm')
1474                                 break;
1475                         p = ch - 1;
1476                         while (ch - p < 10 && *p != '\033')
1477                                 p--;
1478                         if (*p != '\033' ||
1479                             ch + 1 - p != display_mode_esc_sequence_len(p))
1480                                 break;
1481                         /*
1482                          * got a good ansi sequence, put it back to
1483                          * local_sb as we're cutting sb
1484                          */
1485                         strbuf_insert(&local_sb, 0, p, ch + 1 - p);
1486                         ch = p - 1;
1487                 }
1488                 strbuf_setlen(sb, ch + 1 - sb->buf);
1489                 c->flush_type = flush_left;
1490         }
1491
1492         if (len > padding) {
1493                 switch (c->truncate) {
1494                 case trunc_left:
1495                         strbuf_utf8_replace(&local_sb,
1496                                             0, len - (padding - 2),
1497                                             "..");
1498                         break;
1499                 case trunc_middle:
1500                         strbuf_utf8_replace(&local_sb,
1501                                             padding / 2 - 1,
1502                                             len - (padding - 2),
1503                                             "..");
1504                         break;
1505                 case trunc_right:
1506                         strbuf_utf8_replace(&local_sb,
1507                                             padding - 2, len - (padding - 2),
1508                                             "..");
1509                         break;
1510                 case trunc_none:
1511                         break;
1512                 }
1513                 strbuf_addbuf(sb, &local_sb);
1514         } else {
1515                 int sb_len = sb->len, offset = 0;
1516                 if (c->flush_type == flush_left)
1517                         offset = padding - len;
1518                 else if (c->flush_type == flush_both)
1519                         offset = (padding - len) / 2;
1520                 /*
1521                  * we calculate padding in columns, now
1522                  * convert it back to chars
1523                  */
1524                 padding = padding - len + local_sb.len;
1525                 strbuf_addchars(sb, ' ', padding);
1526                 memcpy(sb->buf + sb_len + offset, local_sb.buf,
1527                        local_sb.len);
1528         }
1529         strbuf_release(&local_sb);
1530         c->flush_type = no_flush;
1531         return total_consumed;
1532 }
1533
1534 static size_t format_commit_item(struct strbuf *sb, /* in UTF-8 */
1535                                  const char *placeholder,
1536                                  void *context)
1537 {
1538         int consumed;
1539         size_t orig_len;
1540         enum {
1541                 NO_MAGIC,
1542                 ADD_LF_BEFORE_NON_EMPTY,
1543                 DEL_LF_BEFORE_EMPTY,
1544                 ADD_SP_BEFORE_NON_EMPTY
1545         } magic = NO_MAGIC;
1546
1547         switch (placeholder[0]) {
1548         case '-':
1549                 magic = DEL_LF_BEFORE_EMPTY;
1550                 break;
1551         case '+':
1552                 magic = ADD_LF_BEFORE_NON_EMPTY;
1553                 break;
1554         case ' ':
1555                 magic = ADD_SP_BEFORE_NON_EMPTY;
1556                 break;
1557         default:
1558                 break;
1559         }
1560         if (magic != NO_MAGIC)
1561                 placeholder++;
1562
1563         orig_len = sb->len;
1564         if (((struct format_commit_context *)context)->flush_type != no_flush)
1565                 consumed = format_and_pad_commit(sb, placeholder, context);
1566         else
1567                 consumed = format_commit_one(sb, placeholder, context);
1568         if (magic == NO_MAGIC)
1569                 return consumed;
1570
1571         if ((orig_len == sb->len) && magic == DEL_LF_BEFORE_EMPTY) {
1572                 while (sb->len && sb->buf[sb->len - 1] == '\n')
1573                         strbuf_setlen(sb, sb->len - 1);
1574         } else if (orig_len != sb->len) {
1575                 if (magic == ADD_LF_BEFORE_NON_EMPTY)
1576                         strbuf_insert(sb, orig_len, "\n", 1);
1577                 else if (magic == ADD_SP_BEFORE_NON_EMPTY)
1578                         strbuf_insert(sb, orig_len, " ", 1);
1579         }
1580         return consumed + 1;
1581 }
1582
1583 static size_t userformat_want_item(struct strbuf *sb, const char *placeholder,
1584                                    void *context)
1585 {
1586         struct userformat_want *w = context;
1587
1588         if (*placeholder == '+' || *placeholder == '-' || *placeholder == ' ')
1589                 placeholder++;
1590
1591         switch (*placeholder) {
1592         case 'N':
1593                 w->notes = 1;
1594                 break;
1595         case 'S':
1596                 w->source = 1;
1597                 break;
1598         }
1599         return 0;
1600 }
1601
1602 void userformat_find_requirements(const char *fmt, struct userformat_want *w)
1603 {
1604         struct strbuf dummy = STRBUF_INIT;
1605
1606         if (!fmt) {
1607                 if (!user_format)
1608                         return;
1609                 fmt = user_format;
1610         }
1611         strbuf_expand(&dummy, fmt, userformat_want_item, w);
1612         strbuf_release(&dummy);
1613 }
1614
1615 void repo_format_commit_message(struct repository *r,
1616                                 const struct commit *commit,
1617                                 const char *format, struct strbuf *sb,
1618                                 const struct pretty_print_context *pretty_ctx)
1619 {
1620         struct format_commit_context context;
1621         const char *output_enc = pretty_ctx->output_encoding;
1622         const char *utf8 = "UTF-8";
1623
1624         memset(&context, 0, sizeof(context));
1625         context.commit = commit;
1626         context.pretty_ctx = pretty_ctx;
1627         context.wrap_start = sb->len;
1628         /*
1629          * convert a commit message to UTF-8 first
1630          * as far as 'format_commit_item' assumes it in UTF-8
1631          */
1632         context.message = repo_logmsg_reencode(r, commit,
1633                                                &context.commit_encoding,
1634                                                utf8);
1635
1636         strbuf_expand(sb, format, format_commit_item, &context);
1637         rewrap_message_tail(sb, &context, 0, 0, 0);
1638
1639         /* then convert a commit message to an actual output encoding */
1640         if (output_enc) {
1641                 if (same_encoding(utf8, output_enc))
1642                         output_enc = NULL;
1643         } else {
1644                 if (context.commit_encoding &&
1645                     !same_encoding(context.commit_encoding, utf8))
1646                         output_enc = context.commit_encoding;
1647         }
1648
1649         if (output_enc) {
1650                 size_t outsz;
1651                 char *out = reencode_string_len(sb->buf, sb->len,
1652                                                 output_enc, utf8, &outsz);
1653                 if (out)
1654                         strbuf_attach(sb, out, outsz, outsz + 1);
1655         }
1656
1657         free(context.commit_encoding);
1658         repo_unuse_commit_buffer(r, commit, context.message);
1659 }
1660
1661 static void pp_header(struct pretty_print_context *pp,
1662                       const char *encoding,
1663                       const struct commit *commit,
1664                       const char **msg_p,
1665                       struct strbuf *sb)
1666 {
1667         int parents_shown = 0;
1668
1669         for (;;) {
1670                 const char *name, *line = *msg_p;
1671                 int linelen = get_one_line(*msg_p);
1672
1673                 if (!linelen)
1674                         return;
1675                 *msg_p += linelen;
1676
1677                 if (linelen == 1)
1678                         /* End of header */
1679                         return;
1680
1681                 if (pp->fmt == CMIT_FMT_RAW) {
1682                         strbuf_add(sb, line, linelen);
1683                         continue;
1684                 }
1685
1686                 if (starts_with(line, "parent ")) {
1687                         if (linelen != the_hash_algo->hexsz + 8)
1688                                 die("bad parent line in commit");
1689                         continue;
1690                 }
1691
1692                 if (!parents_shown) {
1693                         unsigned num = commit_list_count(commit->parents);
1694                         /* with enough slop */
1695                         strbuf_grow(sb, num * (GIT_MAX_HEXSZ + 10) + 20);
1696                         add_merge_info(pp, sb, commit);
1697                         parents_shown = 1;
1698                 }
1699
1700                 /*
1701                  * MEDIUM == DEFAULT shows only author with dates.
1702                  * FULL shows both authors but not dates.
1703                  * FULLER shows both authors and dates.
1704                  */
1705                 if (skip_prefix(line, "author ", &name)) {
1706                         strbuf_grow(sb, linelen + 80);
1707                         pp_user_info(pp, "Author", sb, name, encoding);
1708                 }
1709                 if (skip_prefix(line, "committer ", &name) &&
1710                     (pp->fmt == CMIT_FMT_FULL || pp->fmt == CMIT_FMT_FULLER)) {
1711                         strbuf_grow(sb, linelen + 80);
1712                         pp_user_info(pp, "Commit", sb, name, encoding);
1713                 }
1714         }
1715 }
1716
1717 void pp_title_line(struct pretty_print_context *pp,
1718                    const char **msg_p,
1719                    struct strbuf *sb,
1720                    const char *encoding,
1721                    int need_8bit_cte)
1722 {
1723         static const int max_length = 78; /* per rfc2047 */
1724         struct strbuf title;
1725
1726         strbuf_init(&title, 80);
1727         *msg_p = format_subject(&title, *msg_p,
1728                                 pp->preserve_subject ? "\n" : " ");
1729
1730         strbuf_grow(sb, title.len + 1024);
1731         if (pp->print_email_subject) {
1732                 if (pp->rev)
1733                         fmt_output_email_subject(sb, pp->rev);
1734                 if (needs_rfc2047_encoding(title.buf, title.len))
1735                         add_rfc2047(sb, title.buf, title.len,
1736                                                 encoding, RFC2047_SUBJECT);
1737                 else
1738                         strbuf_add_wrapped_bytes(sb, title.buf, title.len,
1739                                          -last_line_length(sb), 1, max_length);
1740         } else {
1741                 strbuf_addbuf(sb, &title);
1742         }
1743         strbuf_addch(sb, '\n');
1744
1745         if (need_8bit_cte == 0) {
1746                 int i;
1747                 for (i = 0; i < pp->in_body_headers.nr; i++) {
1748                         if (has_non_ascii(pp->in_body_headers.items[i].string)) {
1749                                 need_8bit_cte = 1;
1750                                 break;
1751                         }
1752                 }
1753         }
1754
1755         if (need_8bit_cte > 0) {
1756                 const char *header_fmt =
1757                         "MIME-Version: 1.0\n"
1758                         "Content-Type: text/plain; charset=%s\n"
1759                         "Content-Transfer-Encoding: 8bit\n";
1760                 strbuf_addf(sb, header_fmt, encoding);
1761         }
1762         if (pp->after_subject) {
1763                 strbuf_addstr(sb, pp->after_subject);
1764         }
1765         if (cmit_fmt_is_mail(pp->fmt)) {
1766                 strbuf_addch(sb, '\n');
1767         }
1768
1769         if (pp->in_body_headers.nr) {
1770                 int i;
1771                 for (i = 0; i < pp->in_body_headers.nr; i++) {
1772                         strbuf_addstr(sb, pp->in_body_headers.items[i].string);
1773                         free(pp->in_body_headers.items[i].string);
1774                 }
1775                 string_list_clear(&pp->in_body_headers, 0);
1776                 strbuf_addch(sb, '\n');
1777         }
1778
1779         strbuf_release(&title);
1780 }
1781
1782 static int pp_utf8_width(const char *start, const char *end)
1783 {
1784         int width = 0;
1785         size_t remain = end - start;
1786
1787         while (remain) {
1788                 int n = utf8_width(&start, &remain);
1789                 if (n < 0 || !start)
1790                         return -1;
1791                 width += n;
1792         }
1793         return width;
1794 }
1795
1796 static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,
1797                                  const char *line, int linelen)
1798 {
1799         const char *tab;
1800
1801         while ((tab = memchr(line, '\t', linelen)) != NULL) {
1802                 int width = pp_utf8_width(line, tab);
1803
1804                 /*
1805                  * If it wasn't well-formed utf8, or it
1806                  * had characters with badly defined
1807                  * width (control characters etc), just
1808                  * give up on trying to align things.
1809                  */
1810                 if (width < 0)
1811                         break;
1812
1813                 /* Output the data .. */
1814                 strbuf_add(sb, line, tab - line);
1815
1816                 /* .. and the de-tabified tab */
1817                 strbuf_addchars(sb, ' ', tabwidth - (width % tabwidth));
1818
1819                 /* Skip over the printed part .. */
1820                 linelen -= tab + 1 - line;
1821                 line = tab + 1;
1822         }
1823
1824         /*
1825          * Print out everything after the last tab without
1826          * worrying about width - there's nothing more to
1827          * align.
1828          */
1829         strbuf_add(sb, line, linelen);
1830 }
1831
1832 /*
1833  * pp_handle_indent() prints out the intendation, and
1834  * the whole line (without the final newline), after
1835  * de-tabifying.
1836  */
1837 static void pp_handle_indent(struct pretty_print_context *pp,
1838                              struct strbuf *sb, int indent,
1839                              const char *line, int linelen)
1840 {
1841         strbuf_addchars(sb, ' ', indent);
1842         if (pp->expand_tabs_in_log)
1843                 strbuf_add_tabexpand(sb, pp->expand_tabs_in_log, line, linelen);
1844         else
1845                 strbuf_add(sb, line, linelen);
1846 }
1847
1848 static int is_mboxrd_from(const char *line, int len)
1849 {
1850         /*
1851          * a line matching /^From $/ here would only have len == 4
1852          * at this point because is_empty_line would've trimmed all
1853          * trailing space
1854          */
1855         return len > 4 && starts_with(line + strspn(line, ">"), "From ");
1856 }
1857
1858 void pp_remainder(struct pretty_print_context *pp,
1859                   const char **msg_p,
1860                   struct strbuf *sb,
1861                   int indent)
1862 {
1863         int first = 1;
1864         for (;;) {
1865                 const char *line = *msg_p;
1866                 int linelen = get_one_line(line);
1867                 *msg_p += linelen;
1868
1869                 if (!linelen)
1870                         break;
1871
1872                 if (is_blank_line(line, &linelen)) {
1873                         if (first)
1874                                 continue;
1875                         if (pp->fmt == CMIT_FMT_SHORT)
1876                                 break;
1877                 }
1878                 first = 0;
1879
1880                 strbuf_grow(sb, linelen + indent + 20);
1881                 if (indent)
1882                         pp_handle_indent(pp, sb, indent, line, linelen);
1883                 else if (pp->expand_tabs_in_log)
1884                         strbuf_add_tabexpand(sb, pp->expand_tabs_in_log,
1885                                              line, linelen);
1886                 else {
1887                         if (pp->fmt == CMIT_FMT_MBOXRD &&
1888                                         is_mboxrd_from(line, linelen))
1889                                 strbuf_addch(sb, '>');
1890
1891                         strbuf_add(sb, line, linelen);
1892                 }
1893                 strbuf_addch(sb, '\n');
1894         }
1895 }
1896
1897 void pretty_print_commit(struct pretty_print_context *pp,
1898                          const struct commit *commit,
1899                          struct strbuf *sb)
1900 {
1901         unsigned long beginning_of_body;
1902         int indent = 4;
1903         const char *msg;
1904         const char *reencoded;
1905         const char *encoding;
1906         int need_8bit_cte = pp->need_8bit_cte;
1907
1908         if (pp->fmt == CMIT_FMT_USERFORMAT) {
1909                 format_commit_message(commit, user_format, sb, pp);
1910                 return;
1911         }
1912
1913         encoding = get_log_output_encoding();
1914         msg = reencoded = logmsg_reencode(commit, NULL, encoding);
1915
1916         if (pp->fmt == CMIT_FMT_ONELINE || cmit_fmt_is_mail(pp->fmt))
1917                 indent = 0;
1918
1919         /*
1920          * We need to check and emit Content-type: to mark it
1921          * as 8-bit if we haven't done so.
1922          */
1923         if (cmit_fmt_is_mail(pp->fmt) && need_8bit_cte == 0) {
1924                 int i, ch, in_body;
1925
1926                 for (in_body = i = 0; (ch = msg[i]); i++) {
1927                         if (!in_body) {
1928                                 /* author could be non 7-bit ASCII but
1929                                  * the log may be so; skip over the
1930                                  * header part first.
1931                                  */
1932                                 if (ch == '\n' && msg[i+1] == '\n')
1933                                         in_body = 1;
1934                         }
1935                         else if (non_ascii(ch)) {
1936                                 need_8bit_cte = 1;
1937                                 break;
1938                         }
1939                 }
1940         }
1941
1942         pp_header(pp, encoding, commit, &msg, sb);
1943         if (pp->fmt != CMIT_FMT_ONELINE && !pp->print_email_subject) {
1944                 strbuf_addch(sb, '\n');
1945         }
1946
1947         /* Skip excess blank lines at the beginning of body, if any... */
1948         msg = skip_blank_lines(msg);
1949
1950         /* These formats treat the title line specially. */
1951         if (pp->fmt == CMIT_FMT_ONELINE || cmit_fmt_is_mail(pp->fmt))
1952                 pp_title_line(pp, &msg, sb, encoding, need_8bit_cte);
1953
1954         beginning_of_body = sb->len;
1955         if (pp->fmt != CMIT_FMT_ONELINE)
1956                 pp_remainder(pp, &msg, sb, indent);
1957         strbuf_rtrim(sb);
1958
1959         /* Make sure there is an EOLN for the non-oneline case */
1960         if (pp->fmt != CMIT_FMT_ONELINE)
1961                 strbuf_addch(sb, '\n');
1962
1963         /*
1964          * The caller may append additional body text in e-mail
1965          * format.  Make sure we did not strip the blank line
1966          * between the header and the body.
1967          */
1968         if (cmit_fmt_is_mail(pp->fmt) && sb->len <= beginning_of_body)
1969                 strbuf_addch(sb, '\n');
1970
1971         unuse_commit_buffer(commit, reencoded);
1972 }
1973
1974 void pp_commit_easy(enum cmit_fmt fmt, const struct commit *commit,
1975                     struct strbuf *sb)
1976 {
1977         struct pretty_print_context pp = {0};
1978         pp.fmt = fmt;
1979         pretty_print_commit(&pp, commit, sb);
1980 }