Merge branch 'jc/conf-var-doc'
[git] / builtin / show-branch.c
1 #include "cache.h"
2 #include "commit.h"
3 #include "refs.h"
4 #include "builtin.h"
5 #include "color.h"
6 #include "parse-options.h"
7
8 static const char* show_branch_usage[] = {
9     N_("git show-branch [-a | --all] [-r | --remotes] [--topo-order | --date-order]\n"
10        "                [--current] [--color[=<when>] | --no-color] [--sparse]\n"
11        "                [--more=<n> | --list | --independent | --merge-base]\n"
12        "                [--no-name | --sha1-name] [--topics] [(<rev> | <glob>)...]"),
13     N_("git show-branch (-g | --reflog)[=<n>[,<base>]] [--list] [<ref>]"),
14     NULL
15 };
16
17 static int showbranch_use_color = -1;
18
19 static int default_num;
20 static int default_alloc;
21 static const char **default_arg;
22
23 #define UNINTERESTING   01
24
25 #define REV_SHIFT        2
26 #define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
27
28 #define DEFAULT_REFLOG  4
29
30 static const char *get_color_code(int idx)
31 {
32         if (want_color(showbranch_use_color))
33                 return column_colors_ansi[idx % column_colors_ansi_max];
34         return "";
35 }
36
37 static const char *get_color_reset_code(void)
38 {
39         if (want_color(showbranch_use_color))
40                 return GIT_COLOR_RESET;
41         return "";
42 }
43
44 static struct commit *interesting(struct commit_list *list)
45 {
46         while (list) {
47                 struct commit *commit = list->item;
48                 list = list->next;
49                 if (commit->object.flags & UNINTERESTING)
50                         continue;
51                 return commit;
52         }
53         return NULL;
54 }
55
56 static struct commit *pop_one_commit(struct commit_list **list_p)
57 {
58         struct commit *commit;
59         struct commit_list *list;
60         list = *list_p;
61         commit = list->item;
62         *list_p = list->next;
63         free(list);
64         return commit;
65 }
66
67 struct commit_name {
68         const char *head_name; /* which head's ancestor? */
69         int generation; /* how many parents away from head_name */
70 };
71
72 /* Name the commit as nth generation ancestor of head_name;
73  * we count only the first-parent relationship for naming purposes.
74  */
75 static void name_commit(struct commit *commit, const char *head_name, int nth)
76 {
77         struct commit_name *name;
78         if (!commit->util)
79                 commit->util = xmalloc(sizeof(struct commit_name));
80         name = commit->util;
81         name->head_name = head_name;
82         name->generation = nth;
83 }
84
85 /* Parent is the first parent of the commit.  We may name it
86  * as (n+1)th generation ancestor of the same head_name as
87  * commit is nth generation ancestor of, if that generation
88  * number is better than the name it already has.
89  */
90 static void name_parent(struct commit *commit, struct commit *parent)
91 {
92         struct commit_name *commit_name = commit->util;
93         struct commit_name *parent_name = parent->util;
94         if (!commit_name)
95                 return;
96         if (!parent_name ||
97             commit_name->generation + 1 < parent_name->generation)
98                 name_commit(parent, commit_name->head_name,
99                             commit_name->generation + 1);
100 }
101
102 static int name_first_parent_chain(struct commit *c)
103 {
104         int i = 0;
105         while (c) {
106                 struct commit *p;
107                 if (!c->util)
108                         break;
109                 if (!c->parents)
110                         break;
111                 p = c->parents->item;
112                 if (!p->util) {
113                         name_parent(c, p);
114                         i++;
115                 }
116                 else
117                         break;
118                 c = p;
119         }
120         return i;
121 }
122
123 static void name_commits(struct commit_list *list,
124                          struct commit **rev,
125                          char **ref_name,
126                          int num_rev)
127 {
128         struct commit_list *cl;
129         struct commit *c;
130         int i;
131
132         /* First give names to the given heads */
133         for (cl = list; cl; cl = cl->next) {
134                 c = cl->item;
135                 if (c->util)
136                         continue;
137                 for (i = 0; i < num_rev; i++) {
138                         if (rev[i] == c) {
139                                 name_commit(c, ref_name[i], 0);
140                                 break;
141                         }
142                 }
143         }
144
145         /* Then commits on the first parent ancestry chain */
146         do {
147                 i = 0;
148                 for (cl = list; cl; cl = cl->next) {
149                         i += name_first_parent_chain(cl->item);
150                 }
151         } while (i);
152
153         /* Finally, any unnamed commits */
154         do {
155                 i = 0;
156                 for (cl = list; cl; cl = cl->next) {
157                         struct commit_list *parents;
158                         struct commit_name *n;
159                         int nth;
160                         c = cl->item;
161                         if (!c->util)
162                                 continue;
163                         n = c->util;
164                         parents = c->parents;
165                         nth = 0;
166                         while (parents) {
167                                 struct commit *p = parents->item;
168                                 struct strbuf newname = STRBUF_INIT;
169                                 parents = parents->next;
170                                 nth++;
171                                 if (p->util)
172                                         continue;
173                                 switch (n->generation) {
174                                 case 0:
175                                         strbuf_addstr(&newname, n->head_name);
176                                         break;
177                                 case 1:
178                                         strbuf_addf(&newname, "%s^", n->head_name);
179                                         break;
180                                 default:
181                                         strbuf_addf(&newname, "%s~%d",
182                                                     n->head_name, n->generation);
183                                         break;
184                                 }
185                                 if (nth == 1)
186                                         strbuf_addch(&newname, '^');
187                                 else
188                                         strbuf_addf(&newname, "^%d", nth);
189                                 name_commit(p, strbuf_detach(&newname, NULL), 0);
190                                 i++;
191                                 name_first_parent_chain(p);
192                         }
193                 }
194         } while (i);
195 }
196
197 static int mark_seen(struct commit *commit, struct commit_list **seen_p)
198 {
199         if (!commit->object.flags) {
200                 commit_list_insert(commit, seen_p);
201                 return 1;
202         }
203         return 0;
204 }
205
206 static void join_revs(struct commit_list **list_p,
207                       struct commit_list **seen_p,
208                       int num_rev, int extra)
209 {
210         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
211         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
212
213         while (*list_p) {
214                 struct commit_list *parents;
215                 int still_interesting = !!interesting(*list_p);
216                 struct commit *commit = pop_one_commit(list_p);
217                 int flags = commit->object.flags & all_mask;
218
219                 if (!still_interesting && extra <= 0)
220                         break;
221
222                 mark_seen(commit, seen_p);
223                 if ((flags & all_revs) == all_revs)
224                         flags |= UNINTERESTING;
225                 parents = commit->parents;
226
227                 while (parents) {
228                         struct commit *p = parents->item;
229                         int this_flag = p->object.flags;
230                         parents = parents->next;
231                         if ((this_flag & flags) == flags)
232                                 continue;
233                         parse_commit(p);
234                         if (mark_seen(p, seen_p) && !still_interesting)
235                                 extra--;
236                         p->object.flags |= flags;
237                         commit_list_insert_by_date(p, list_p);
238                 }
239         }
240
241         /*
242          * Postprocess to complete well-poisoning.
243          *
244          * At this point we have all the commits we have seen in
245          * seen_p list.  Mark anything that can be reached from
246          * uninteresting commits not interesting.
247          */
248         for (;;) {
249                 int changed = 0;
250                 struct commit_list *s;
251                 for (s = *seen_p; s; s = s->next) {
252                         struct commit *c = s->item;
253                         struct commit_list *parents;
254
255                         if (((c->object.flags & all_revs) != all_revs) &&
256                             !(c->object.flags & UNINTERESTING))
257                                 continue;
258
259                         /* The current commit is either a merge base or
260                          * already uninteresting one.  Mark its parents
261                          * as uninteresting commits _only_ if they are
262                          * already parsed.  No reason to find new ones
263                          * here.
264                          */
265                         parents = c->parents;
266                         while (parents) {
267                                 struct commit *p = parents->item;
268                                 parents = parents->next;
269                                 if (!(p->object.flags & UNINTERESTING)) {
270                                         p->object.flags |= UNINTERESTING;
271                                         changed = 1;
272                                 }
273                         }
274                 }
275                 if (!changed)
276                         break;
277         }
278 }
279
280 static void show_one_commit(struct commit *commit, int no_name)
281 {
282         struct strbuf pretty = STRBUF_INIT;
283         const char *pretty_str = "(unavailable)";
284         struct commit_name *name = commit->util;
285
286         if (commit->object.parsed) {
287                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &pretty);
288                 pretty_str = pretty.buf;
289         }
290         if (starts_with(pretty_str, "[PATCH] "))
291                 pretty_str += 8;
292
293         if (!no_name) {
294                 if (name && name->head_name) {
295                         printf("[%s", name->head_name);
296                         if (name->generation) {
297                                 if (name->generation == 1)
298                                         printf("^");
299                                 else
300                                         printf("~%d", name->generation);
301                         }
302                         printf("] ");
303                 }
304                 else
305                         printf("[%s] ",
306                                find_unique_abbrev(commit->object.sha1,
307                                                   DEFAULT_ABBREV));
308         }
309         puts(pretty_str);
310         strbuf_release(&pretty);
311 }
312
313 static char *ref_name[MAX_REVS + 1];
314 static int ref_name_cnt;
315
316 static const char *find_digit_prefix(const char *s, int *v)
317 {
318         const char *p;
319         int ver;
320         char ch;
321
322         for (p = s, ver = 0;
323              '0' <= (ch = *p) && ch <= '9';
324              p++)
325                 ver = ver * 10 + ch - '0';
326         *v = ver;
327         return p;
328 }
329
330
331 static int version_cmp(const char *a, const char *b)
332 {
333         while (1) {
334                 int va, vb;
335
336                 a = find_digit_prefix(a, &va);
337                 b = find_digit_prefix(b, &vb);
338                 if (va != vb)
339                         return va - vb;
340
341                 while (1) {
342                         int ca = *a;
343                         int cb = *b;
344                         if ('0' <= ca && ca <= '9')
345                                 ca = 0;
346                         if ('0' <= cb && cb <= '9')
347                                 cb = 0;
348                         if (ca != cb)
349                                 return ca - cb;
350                         if (!ca)
351                                 break;
352                         a++;
353                         b++;
354                 }
355                 if (!*a && !*b)
356                         return 0;
357         }
358 }
359
360 static int compare_ref_name(const void *a_, const void *b_)
361 {
362         const char * const*a = a_, * const*b = b_;
363         return version_cmp(*a, *b);
364 }
365
366 static void sort_ref_range(int bottom, int top)
367 {
368         qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
369               compare_ref_name);
370 }
371
372 static int append_ref(const char *refname, const unsigned char *sha1,
373                       int allow_dups)
374 {
375         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
376         int i;
377
378         if (!commit)
379                 return 0;
380
381         if (!allow_dups) {
382                 /* Avoid adding the same thing twice */
383                 for (i = 0; i < ref_name_cnt; i++)
384                         if (!strcmp(refname, ref_name[i]))
385                                 return 0;
386         }
387         if (MAX_REVS <= ref_name_cnt) {
388                 warning("ignoring %s; cannot handle more than %d refs",
389                         refname, MAX_REVS);
390                 return 0;
391         }
392         ref_name[ref_name_cnt++] = xstrdup(refname);
393         ref_name[ref_name_cnt] = NULL;
394         return 0;
395 }
396
397 static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
398 {
399         unsigned char tmp[20];
400         int ofs = 11;
401         if (!starts_with(refname, "refs/heads/"))
402                 return 0;
403         /* If both heads/foo and tags/foo exists, get_sha1 would
404          * get confused.
405          */
406         if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
407                 ofs = 5;
408         return append_ref(refname + ofs, sha1, 0);
409 }
410
411 static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
412 {
413         unsigned char tmp[20];
414         int ofs = 13;
415         if (!starts_with(refname, "refs/remotes/"))
416                 return 0;
417         /* If both heads/foo and tags/foo exists, get_sha1 would
418          * get confused.
419          */
420         if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
421                 ofs = 5;
422         return append_ref(refname + ofs, sha1, 0);
423 }
424
425 static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
426 {
427         if (!starts_with(refname, "refs/tags/"))
428                 return 0;
429         return append_ref(refname + 5, sha1, 0);
430 }
431
432 static const char *match_ref_pattern = NULL;
433 static int match_ref_slash = 0;
434 static int count_slash(const char *s)
435 {
436         int cnt = 0;
437         while (*s)
438                 if (*s++ == '/')
439                         cnt++;
440         return cnt;
441 }
442
443 static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
444 {
445         /* we want to allow pattern hold/<asterisk> to show all
446          * branches under refs/heads/hold/, and v0.99.9? to show
447          * refs/tags/v0.99.9a and friends.
448          */
449         const char *tail;
450         int slash = count_slash(refname);
451         for (tail = refname; *tail && match_ref_slash < slash; )
452                 if (*tail++ == '/')
453                         slash--;
454         if (!*tail)
455                 return 0;
456         if (wildmatch(match_ref_pattern, tail, 0, NULL))
457                 return 0;
458         if (starts_with(refname, "refs/heads/"))
459                 return append_head_ref(refname, sha1, flag, cb_data);
460         if (starts_with(refname, "refs/tags/"))
461                 return append_tag_ref(refname, sha1, flag, cb_data);
462         return append_ref(refname, sha1, 0);
463 }
464
465 static void snarf_refs(int head, int remotes)
466 {
467         if (head) {
468                 int orig_cnt = ref_name_cnt;
469                 for_each_ref(append_head_ref, NULL);
470                 sort_ref_range(orig_cnt, ref_name_cnt);
471         }
472         if (remotes) {
473                 int orig_cnt = ref_name_cnt;
474                 for_each_ref(append_remote_ref, NULL);
475                 sort_ref_range(orig_cnt, ref_name_cnt);
476         }
477 }
478
479 static int rev_is_head(char *head, int headlen, char *name,
480                        unsigned char *head_sha1, unsigned char *sha1)
481 {
482         if ((!head[0]) ||
483             (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
484                 return 0;
485         if (starts_with(head, "refs/heads/"))
486                 head += 11;
487         if (starts_with(name, "refs/heads/"))
488                 name += 11;
489         else if (starts_with(name, "heads/"))
490                 name += 6;
491         return !strcmp(head, name);
492 }
493
494 static int show_merge_base(struct commit_list *seen, int num_rev)
495 {
496         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
497         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
498         int exit_status = 1;
499
500         while (seen) {
501                 struct commit *commit = pop_one_commit(&seen);
502                 int flags = commit->object.flags & all_mask;
503                 if (!(flags & UNINTERESTING) &&
504                     ((flags & all_revs) == all_revs)) {
505                         puts(sha1_to_hex(commit->object.sha1));
506                         exit_status = 0;
507                         commit->object.flags |= UNINTERESTING;
508                 }
509         }
510         return exit_status;
511 }
512
513 static int show_independent(struct commit **rev,
514                             int num_rev,
515                             char **ref_name,
516                             unsigned int *rev_mask)
517 {
518         int i;
519
520         for (i = 0; i < num_rev; i++) {
521                 struct commit *commit = rev[i];
522                 unsigned int flag = rev_mask[i];
523
524                 if (commit->object.flags == flag)
525                         puts(sha1_to_hex(commit->object.sha1));
526                 commit->object.flags |= UNINTERESTING;
527         }
528         return 0;
529 }
530
531 static void append_one_rev(const char *av)
532 {
533         unsigned char revkey[20];
534         if (!get_sha1(av, revkey)) {
535                 append_ref(av, revkey, 0);
536                 return;
537         }
538         if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
539                 /* glob style match */
540                 int saved_matches = ref_name_cnt;
541                 match_ref_pattern = av;
542                 match_ref_slash = count_slash(av);
543                 for_each_ref(append_matching_ref, NULL);
544                 if (saved_matches == ref_name_cnt &&
545                     ref_name_cnt < MAX_REVS)
546                         error("no matching refs with %s", av);
547                 if (saved_matches + 1 < ref_name_cnt)
548                         sort_ref_range(saved_matches, ref_name_cnt);
549                 return;
550         }
551         die("bad sha1 reference %s", av);
552 }
553
554 static int git_show_branch_config(const char *var, const char *value, void *cb)
555 {
556         if (!strcmp(var, "showbranch.default")) {
557                 if (!value)
558                         return config_error_nonbool(var);
559                 /*
560                  * default_arg is now passed to parse_options(), so we need to
561                  * mimic the real argv a bit better.
562                  */
563                 if (!default_num) {
564                         default_alloc = 20;
565                         default_arg = xcalloc(default_alloc, sizeof(*default_arg));
566                         default_arg[default_num++] = "show-branch";
567                 } else if (default_alloc <= default_num + 1) {
568                         default_alloc = default_alloc * 3 / 2 + 20;
569                         REALLOC_ARRAY(default_arg, default_alloc);
570                 }
571                 default_arg[default_num++] = xstrdup(value);
572                 default_arg[default_num] = NULL;
573                 return 0;
574         }
575
576         if (!strcmp(var, "color.showbranch")) {
577                 showbranch_use_color = git_config_colorbool(var, value);
578                 return 0;
579         }
580
581         return git_color_default_config(var, value, cb);
582 }
583
584 static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
585 {
586         /* If the commit is tip of the named branches, do not
587          * omit it.
588          * Otherwise, if it is a merge that is reachable from only one
589          * tip, it is not that interesting.
590          */
591         int i, flag, count;
592         for (i = 0; i < n; i++)
593                 if (rev[i] == commit)
594                         return 0;
595         flag = commit->object.flags;
596         for (i = count = 0; i < n; i++) {
597                 if (flag & (1u << (i + REV_SHIFT)))
598                         count++;
599         }
600         if (count == 1)
601                 return 1;
602         return 0;
603 }
604
605 static int reflog = 0;
606
607 static int parse_reflog_param(const struct option *opt, const char *arg,
608                               int unset)
609 {
610         char *ep;
611         const char **base = (const char **)opt->value;
612         if (!arg)
613                 arg = "";
614         reflog = strtoul(arg, &ep, 10);
615         if (*ep == ',')
616                 *base = ep + 1;
617         else if (*ep)
618                 return error("unrecognized reflog param '%s'", arg);
619         else
620                 *base = NULL;
621         if (reflog <= 0)
622                 reflog = DEFAULT_REFLOG;
623         return 0;
624 }
625
626 int cmd_show_branch(int ac, const char **av, const char *prefix)
627 {
628         struct commit *rev[MAX_REVS], *commit;
629         char *reflog_msg[MAX_REVS];
630         struct commit_list *list = NULL, *seen = NULL;
631         unsigned int rev_mask[MAX_REVS];
632         int num_rev, i, extra = 0;
633         int all_heads = 0, all_remotes = 0;
634         int all_mask, all_revs;
635         enum rev_sort_order sort_order = REV_SORT_IN_GRAPH_ORDER;
636         char head[128];
637         const char *head_p;
638         int head_len;
639         unsigned char head_sha1[20];
640         int merge_base = 0;
641         int independent = 0;
642         int no_name = 0;
643         int sha1_name = 0;
644         int shown_merge_point = 0;
645         int with_current_branch = 0;
646         int head_at = -1;
647         int topics = 0;
648         int dense = 1;
649         const char *reflog_base = NULL;
650         struct option builtin_show_branch_options[] = {
651                 OPT_BOOL('a', "all", &all_heads,
652                          N_("show remote-tracking and local branches")),
653                 OPT_BOOL('r', "remotes", &all_remotes,
654                          N_("show remote-tracking branches")),
655                 OPT__COLOR(&showbranch_use_color,
656                             N_("color '*!+-' corresponding to the branch")),
657                 { OPTION_INTEGER, 0, "more", &extra, N_("n"),
658                             N_("show <n> more commits after the common ancestor"),
659                             PARSE_OPT_OPTARG, NULL, (intptr_t)1 },
660                 OPT_SET_INT(0, "list", &extra, N_("synonym to more=-1"), -1),
661                 OPT_BOOL(0, "no-name", &no_name, N_("suppress naming strings")),
662                 OPT_BOOL(0, "current", &with_current_branch,
663                          N_("include the current branch")),
664                 OPT_BOOL(0, "sha1-name", &sha1_name,
665                          N_("name commits with their object names")),
666                 OPT_BOOL(0, "merge-base", &merge_base,
667                          N_("show possible merge bases")),
668                 OPT_BOOL(0, "independent", &independent,
669                             N_("show refs unreachable from any other ref")),
670                 OPT_SET_INT(0, "topo-order", &sort_order,
671                             N_("show commits in topological order"),
672                             REV_SORT_IN_GRAPH_ORDER),
673                 OPT_BOOL(0, "topics", &topics,
674                          N_("show only commits not on the first branch")),
675                 OPT_SET_INT(0, "sparse", &dense,
676                             N_("show merges reachable from only one tip"), 0),
677                 OPT_SET_INT(0, "date-order", &sort_order,
678                             N_("topologically sort, maintaining date order "
679                                "where possible"),
680                             REV_SORT_BY_COMMIT_DATE),
681                 { OPTION_CALLBACK, 'g', "reflog", &reflog_base, N_("<n>[,<base>]"),
682                             N_("show <n> most recent ref-log entries starting at "
683                                "base"),
684                             PARSE_OPT_OPTARG | PARSE_OPT_LITERAL_ARGHELP,
685                             parse_reflog_param },
686                 OPT_END()
687         };
688
689         git_config(git_show_branch_config, NULL);
690
691         /* If nothing is specified, try the default first */
692         if (ac == 1 && default_num) {
693                 ac = default_num;
694                 av = default_arg;
695         }
696
697         ac = parse_options(ac, av, prefix, builtin_show_branch_options,
698                            show_branch_usage, PARSE_OPT_STOP_AT_NON_OPTION);
699         if (all_heads)
700                 all_remotes = 1;
701
702         if (extra || reflog) {
703                 /* "listing" mode is incompatible with
704                  * independent nor merge-base modes.
705                  */
706                 if (independent || merge_base)
707                         usage_with_options(show_branch_usage,
708                                            builtin_show_branch_options);
709                 if (reflog && ((0 < extra) || all_heads || all_remotes))
710                         /*
711                          * Asking for --more in reflog mode does not
712                          * make sense.  --list is Ok.
713                          *
714                          * Also --all and --remotes do not make sense either.
715                          */
716                         die("--reflog is incompatible with --all, --remotes, "
717                             "--independent or --merge-base");
718         }
719
720         /* If nothing is specified, show all branches by default */
721         if (ac + all_heads + all_remotes == 0)
722                 all_heads = 1;
723
724         if (reflog) {
725                 unsigned char sha1[20];
726                 char nth_desc[256];
727                 char *ref;
728                 int base = 0;
729                 unsigned int flags = 0;
730
731                 if (ac == 0) {
732                         static const char *fake_av[2];
733
734                         fake_av[0] = resolve_refdup("HEAD",
735                                                     RESOLVE_REF_READING,
736                                                     sha1, NULL);
737                         fake_av[1] = NULL;
738                         av = fake_av;
739                         ac = 1;
740                 }
741                 if (ac != 1)
742                         die("--reflog option needs one branch name");
743
744                 if (MAX_REVS < reflog)
745                         die("Only %d entries can be shown at one time.",
746                             MAX_REVS);
747                 if (!dwim_ref(*av, strlen(*av), sha1, &ref))
748                         die("No such ref %s", *av);
749
750                 /* Has the base been specified? */
751                 if (reflog_base) {
752                         char *ep;
753                         base = strtoul(reflog_base, &ep, 10);
754                         if (*ep) {
755                                 /* Ah, that is a date spec... */
756                                 unsigned long at;
757                                 at = approxidate(reflog_base);
758                                 read_ref_at(ref, flags, at, -1, sha1, NULL,
759                                             NULL, NULL, &base);
760                         }
761                 }
762
763                 for (i = 0; i < reflog; i++) {
764                         char *logmsg;
765                         const char *msg;
766                         unsigned long timestamp;
767                         int tz;
768
769                         if (read_ref_at(ref, flags, 0, base+i, sha1, &logmsg,
770                                         &timestamp, &tz, NULL)) {
771                                 reflog = i;
772                                 break;
773                         }
774                         msg = strchr(logmsg, '\t');
775                         if (!msg)
776                                 msg = "(none)";
777                         else
778                                 msg++;
779                         reflog_msg[i] = xstrfmt("(%s) %s",
780                                                 show_date(timestamp, tz, 1),
781                                                 msg);
782                         free(logmsg);
783                         sprintf(nth_desc, "%s@{%d}", *av, base+i);
784                         append_ref(nth_desc, sha1, 1);
785                 }
786                 free(ref);
787         }
788         else if (all_heads + all_remotes)
789                 snarf_refs(all_heads, all_remotes);
790         else {
791                 while (0 < ac) {
792                         append_one_rev(*av);
793                         ac--; av++;
794                 }
795         }
796
797         head_p = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
798                                     head_sha1, NULL);
799         if (head_p) {
800                 head_len = strlen(head_p);
801                 memcpy(head, head_p, head_len + 1);
802         }
803         else {
804                 head_len = 0;
805                 head[0] = 0;
806         }
807
808         if (with_current_branch && head_p) {
809                 int has_head = 0;
810                 for (i = 0; !has_head && i < ref_name_cnt; i++) {
811                         /* We are only interested in adding the branch
812                          * HEAD points at.
813                          */
814                         if (rev_is_head(head,
815                                         head_len,
816                                         ref_name[i],
817                                         head_sha1, NULL))
818                                 has_head++;
819                 }
820                 if (!has_head) {
821                         int offset = starts_with(head, "refs/heads/") ? 11 : 0;
822                         append_one_rev(head + offset);
823                 }
824         }
825
826         if (!ref_name_cnt) {
827                 fprintf(stderr, "No revs to be shown.\n");
828                 exit(0);
829         }
830
831         for (num_rev = 0; ref_name[num_rev]; num_rev++) {
832                 unsigned char revkey[20];
833                 unsigned int flag = 1u << (num_rev + REV_SHIFT);
834
835                 if (MAX_REVS <= num_rev)
836                         die("cannot handle more than %d revs.", MAX_REVS);
837                 if (get_sha1(ref_name[num_rev], revkey))
838                         die("'%s' is not a valid ref.", ref_name[num_rev]);
839                 commit = lookup_commit_reference(revkey);
840                 if (!commit)
841                         die("cannot find commit %s (%s)",
842                             ref_name[num_rev], revkey);
843                 parse_commit(commit);
844                 mark_seen(commit, &seen);
845
846                 /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
847                  * and so on.  REV_SHIFT bits from bit 0 are used for
848                  * internal bookkeeping.
849                  */
850                 commit->object.flags |= flag;
851                 if (commit->object.flags == flag)
852                         commit_list_insert_by_date(commit, &list);
853                 rev[num_rev] = commit;
854         }
855         for (i = 0; i < num_rev; i++)
856                 rev_mask[i] = rev[i]->object.flags;
857
858         if (0 <= extra)
859                 join_revs(&list, &seen, num_rev, extra);
860
861         commit_list_sort_by_date(&seen);
862
863         if (merge_base)
864                 return show_merge_base(seen, num_rev);
865
866         if (independent)
867                 return show_independent(rev, num_rev, ref_name, rev_mask);
868
869         /* Show list; --more=-1 means list-only */
870         if (1 < num_rev || extra < 0) {
871                 for (i = 0; i < num_rev; i++) {
872                         int j;
873                         int is_head = rev_is_head(head,
874                                                   head_len,
875                                                   ref_name[i],
876                                                   head_sha1,
877                                                   rev[i]->object.sha1);
878                         if (extra < 0)
879                                 printf("%c [%s] ",
880                                        is_head ? '*' : ' ', ref_name[i]);
881                         else {
882                                 for (j = 0; j < i; j++)
883                                         putchar(' ');
884                                 printf("%s%c%s [%s] ",
885                                        get_color_code(i),
886                                        is_head ? '*' : '!',
887                                        get_color_reset_code(), ref_name[i]);
888                         }
889
890                         if (!reflog) {
891                                 /* header lines never need name */
892                                 show_one_commit(rev[i], 1);
893                         }
894                         else
895                                 puts(reflog_msg[i]);
896
897                         if (is_head)
898                                 head_at = i;
899                 }
900                 if (0 <= extra) {
901                         for (i = 0; i < num_rev; i++)
902                                 putchar('-');
903                         putchar('\n');
904                 }
905         }
906         if (extra < 0)
907                 exit(0);
908
909         /* Sort topologically */
910         sort_in_topological_order(&seen, sort_order);
911
912         /* Give names to commits */
913         if (!sha1_name && !no_name)
914                 name_commits(seen, rev, ref_name, num_rev);
915
916         all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
917         all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
918
919         while (seen) {
920                 struct commit *commit = pop_one_commit(&seen);
921                 int this_flag = commit->object.flags;
922                 int is_merge_point = ((this_flag & all_revs) == all_revs);
923
924                 shown_merge_point |= is_merge_point;
925
926                 if (1 < num_rev) {
927                         int is_merge = !!(commit->parents &&
928                                           commit->parents->next);
929                         if (topics &&
930                             !is_merge_point &&
931                             (this_flag & (1u << REV_SHIFT)))
932                                 continue;
933                         if (dense && is_merge &&
934                             omit_in_dense(commit, rev, num_rev))
935                                 continue;
936                         for (i = 0; i < num_rev; i++) {
937                                 int mark;
938                                 if (!(this_flag & (1u << (i + REV_SHIFT))))
939                                         mark = ' ';
940                                 else if (is_merge)
941                                         mark = '-';
942                                 else if (i == head_at)
943                                         mark = '*';
944                                 else
945                                         mark = '+';
946                                 printf("%s%c%s",
947                                        get_color_code(i),
948                                        mark, get_color_reset_code());
949                         }
950                         putchar(' ');
951                 }
952                 show_one_commit(commit, no_name);
953
954                 if (shown_merge_point && --extra < 0)
955                         break;
956         }
957         return 0;
958 }