Merge branch 'bg/maint-remote-update-default' into maint
[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     "git show-branch [-a|--all] [-r|--remotes] [--topo-order | --date-order] [--current] [--color | --no-color] [--sparse] [--more=<n> | --list | --independent | --merge-base] [--no-name | --sha1-name] [--topics] [<rev> | <glob>]...",
10     "git show-branch (-g|--reflog)[=<n>[,<base>]] [--list] [<ref>]",
11     NULL
12 };
13
14 static int showbranch_use_color = -1;
15 static char column_colors[][COLOR_MAXLEN] = {
16         GIT_COLOR_RED,
17         GIT_COLOR_GREEN,
18         GIT_COLOR_YELLOW,
19         GIT_COLOR_BLUE,
20         GIT_COLOR_MAGENTA,
21         GIT_COLOR_CYAN,
22 };
23
24 #define COLUMN_COLORS_MAX (ARRAY_SIZE(column_colors))
25
26 static int default_num;
27 static int default_alloc;
28 static const char **default_arg;
29
30 #define UNINTERESTING   01
31
32 #define REV_SHIFT        2
33 #define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
34
35 #define DEFAULT_REFLOG  4
36
37 static const char *get_color_code(int idx)
38 {
39         if (showbranch_use_color)
40                 return column_colors[idx];
41         return "";
42 }
43
44 static const char *get_color_reset_code(void)
45 {
46         if (showbranch_use_color)
47                 return GIT_COLOR_RESET;
48         return "";
49 }
50
51 static struct commit *interesting(struct commit_list *list)
52 {
53         while (list) {
54                 struct commit *commit = list->item;
55                 list = list->next;
56                 if (commit->object.flags & UNINTERESTING)
57                         continue;
58                 return commit;
59         }
60         return NULL;
61 }
62
63 static struct commit *pop_one_commit(struct commit_list **list_p)
64 {
65         struct commit *commit;
66         struct commit_list *list;
67         list = *list_p;
68         commit = list->item;
69         *list_p = list->next;
70         free(list);
71         return commit;
72 }
73
74 struct commit_name {
75         const char *head_name; /* which head's ancestor? */
76         int generation; /* how many parents away from head_name */
77 };
78
79 /* Name the commit as nth generation ancestor of head_name;
80  * we count only the first-parent relationship for naming purposes.
81  */
82 static void name_commit(struct commit *commit, const char *head_name, int nth)
83 {
84         struct commit_name *name;
85         if (!commit->util)
86                 commit->util = xmalloc(sizeof(struct commit_name));
87         name = commit->util;
88         name->head_name = head_name;
89         name->generation = nth;
90 }
91
92 /* Parent is the first parent of the commit.  We may name it
93  * as (n+1)th generation ancestor of the same head_name as
94  * commit is nth generation ancestor of, if that generation
95  * number is better than the name it already has.
96  */
97 static void name_parent(struct commit *commit, struct commit *parent)
98 {
99         struct commit_name *commit_name = commit->util;
100         struct commit_name *parent_name = parent->util;
101         if (!commit_name)
102                 return;
103         if (!parent_name ||
104             commit_name->generation + 1 < parent_name->generation)
105                 name_commit(parent, commit_name->head_name,
106                             commit_name->generation + 1);
107 }
108
109 static int name_first_parent_chain(struct commit *c)
110 {
111         int i = 0;
112         while (c) {
113                 struct commit *p;
114                 if (!c->util)
115                         break;
116                 if (!c->parents)
117                         break;
118                 p = c->parents->item;
119                 if (!p->util) {
120                         name_parent(c, p);
121                         i++;
122                 }
123                 else
124                         break;
125                 c = p;
126         }
127         return i;
128 }
129
130 static void name_commits(struct commit_list *list,
131                          struct commit **rev,
132                          char **ref_name,
133                          int num_rev)
134 {
135         struct commit_list *cl;
136         struct commit *c;
137         int i;
138
139         /* First give names to the given heads */
140         for (cl = list; cl; cl = cl->next) {
141                 c = cl->item;
142                 if (c->util)
143                         continue;
144                 for (i = 0; i < num_rev; i++) {
145                         if (rev[i] == c) {
146                                 name_commit(c, ref_name[i], 0);
147                                 break;
148                         }
149                 }
150         }
151
152         /* Then commits on the first parent ancestry chain */
153         do {
154                 i = 0;
155                 for (cl = list; cl; cl = cl->next) {
156                         i += name_first_parent_chain(cl->item);
157                 }
158         } while (i);
159
160         /* Finally, any unnamed commits */
161         do {
162                 i = 0;
163                 for (cl = list; cl; cl = cl->next) {
164                         struct commit_list *parents;
165                         struct commit_name *n;
166                         int nth;
167                         c = cl->item;
168                         if (!c->util)
169                                 continue;
170                         n = c->util;
171                         parents = c->parents;
172                         nth = 0;
173                         while (parents) {
174                                 struct commit *p = parents->item;
175                                 char newname[1000], *en;
176                                 parents = parents->next;
177                                 nth++;
178                                 if (p->util)
179                                         continue;
180                                 en = newname;
181                                 switch (n->generation) {
182                                 case 0:
183                                         en += sprintf(en, "%s", n->head_name);
184                                         break;
185                                 case 1:
186                                         en += sprintf(en, "%s^", n->head_name);
187                                         break;
188                                 default:
189                                         en += sprintf(en, "%s~%d",
190                                                 n->head_name, n->generation);
191                                         break;
192                                 }
193                                 if (nth == 1)
194                                         en += sprintf(en, "^");
195                                 else
196                                         en += sprintf(en, "^%d", nth);
197                                 name_commit(p, xstrdup(newname), 0);
198                                 i++;
199                                 name_first_parent_chain(p);
200                         }
201                 }
202         } while (i);
203 }
204
205 static int mark_seen(struct commit *commit, struct commit_list **seen_p)
206 {
207         if (!commit->object.flags) {
208                 commit_list_insert(commit, seen_p);
209                 return 1;
210         }
211         return 0;
212 }
213
214 static void join_revs(struct commit_list **list_p,
215                       struct commit_list **seen_p,
216                       int num_rev, int extra)
217 {
218         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
219         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
220
221         while (*list_p) {
222                 struct commit_list *parents;
223                 int still_interesting = !!interesting(*list_p);
224                 struct commit *commit = pop_one_commit(list_p);
225                 int flags = commit->object.flags & all_mask;
226
227                 if (!still_interesting && extra <= 0)
228                         break;
229
230                 mark_seen(commit, seen_p);
231                 if ((flags & all_revs) == all_revs)
232                         flags |= UNINTERESTING;
233                 parents = commit->parents;
234
235                 while (parents) {
236                         struct commit *p = parents->item;
237                         int this_flag = p->object.flags;
238                         parents = parents->next;
239                         if ((this_flag & flags) == flags)
240                                 continue;
241                         if (!p->object.parsed)
242                                 parse_commit(p);
243                         if (mark_seen(p, seen_p) && !still_interesting)
244                                 extra--;
245                         p->object.flags |= flags;
246                         insert_by_date(p, list_p);
247                 }
248         }
249
250         /*
251          * Postprocess to complete well-poisoning.
252          *
253          * At this point we have all the commits we have seen in
254          * seen_p list.  Mark anything that can be reached from
255          * uninteresting commits not interesting.
256          */
257         for (;;) {
258                 int changed = 0;
259                 struct commit_list *s;
260                 for (s = *seen_p; s; s = s->next) {
261                         struct commit *c = s->item;
262                         struct commit_list *parents;
263
264                         if (((c->object.flags & all_revs) != all_revs) &&
265                             !(c->object.flags & UNINTERESTING))
266                                 continue;
267
268                         /* The current commit is either a merge base or
269                          * already uninteresting one.  Mark its parents
270                          * as uninteresting commits _only_ if they are
271                          * already parsed.  No reason to find new ones
272                          * here.
273                          */
274                         parents = c->parents;
275                         while (parents) {
276                                 struct commit *p = parents->item;
277                                 parents = parents->next;
278                                 if (!(p->object.flags & UNINTERESTING)) {
279                                         p->object.flags |= UNINTERESTING;
280                                         changed = 1;
281                                 }
282                         }
283                 }
284                 if (!changed)
285                         break;
286         }
287 }
288
289 static void show_one_commit(struct commit *commit, int no_name)
290 {
291         struct strbuf pretty = STRBUF_INIT;
292         const char *pretty_str = "(unavailable)";
293         struct commit_name *name = commit->util;
294
295         if (commit->object.parsed) {
296                 struct pretty_print_context ctx = {0};
297                 pretty_print_commit(CMIT_FMT_ONELINE, commit, &pretty, &ctx);
298                 pretty_str = pretty.buf;
299         }
300         if (!prefixcmp(pretty_str, "[PATCH] "))
301                 pretty_str += 8;
302
303         if (!no_name) {
304                 if (name && name->head_name) {
305                         printf("[%s", name->head_name);
306                         if (name->generation) {
307                                 if (name->generation == 1)
308                                         printf("^");
309                                 else
310                                         printf("~%d", name->generation);
311                         }
312                         printf("] ");
313                 }
314                 else
315                         printf("[%s] ",
316                                find_unique_abbrev(commit->object.sha1, 7));
317         }
318         puts(pretty_str);
319         strbuf_release(&pretty);
320 }
321
322 static char *ref_name[MAX_REVS + 1];
323 static int ref_name_cnt;
324
325 static const char *find_digit_prefix(const char *s, int *v)
326 {
327         const char *p;
328         int ver;
329         char ch;
330
331         for (p = s, ver = 0;
332              '0' <= (ch = *p) && ch <= '9';
333              p++)
334                 ver = ver * 10 + ch - '0';
335         *v = ver;
336         return p;
337 }
338
339
340 static int version_cmp(const char *a, const char *b)
341 {
342         while (1) {
343                 int va, vb;
344
345                 a = find_digit_prefix(a, &va);
346                 b = find_digit_prefix(b, &vb);
347                 if (va != vb)
348                         return va - vb;
349
350                 while (1) {
351                         int ca = *a;
352                         int cb = *b;
353                         if ('0' <= ca && ca <= '9')
354                                 ca = 0;
355                         if ('0' <= cb && cb <= '9')
356                                 cb = 0;
357                         if (ca != cb)
358                                 return ca - cb;
359                         if (!ca)
360                                 break;
361                         a++;
362                         b++;
363                 }
364                 if (!*a && !*b)
365                         return 0;
366         }
367 }
368
369 static int compare_ref_name(const void *a_, const void *b_)
370 {
371         const char * const*a = a_, * const*b = b_;
372         return version_cmp(*a, *b);
373 }
374
375 static void sort_ref_range(int bottom, int top)
376 {
377         qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
378               compare_ref_name);
379 }
380
381 static int append_ref(const char *refname, const unsigned char *sha1,
382                       int allow_dups)
383 {
384         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
385         int i;
386
387         if (!commit)
388                 return 0;
389
390         if (!allow_dups) {
391                 /* Avoid adding the same thing twice */
392                 for (i = 0; i < ref_name_cnt; i++)
393                         if (!strcmp(refname, ref_name[i]))
394                                 return 0;
395         }
396         if (MAX_REVS <= ref_name_cnt) {
397                 warning("ignoring %s; cannot handle more than %d refs",
398                         refname, MAX_REVS);
399                 return 0;
400         }
401         ref_name[ref_name_cnt++] = xstrdup(refname);
402         ref_name[ref_name_cnt] = NULL;
403         return 0;
404 }
405
406 static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
407 {
408         unsigned char tmp[20];
409         int ofs = 11;
410         if (prefixcmp(refname, "refs/heads/"))
411                 return 0;
412         /* If both heads/foo and tags/foo exists, get_sha1 would
413          * get confused.
414          */
415         if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
416                 ofs = 5;
417         return append_ref(refname + ofs, sha1, 0);
418 }
419
420 static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
421 {
422         unsigned char tmp[20];
423         int ofs = 13;
424         if (prefixcmp(refname, "refs/remotes/"))
425                 return 0;
426         /* If both heads/foo and tags/foo exists, get_sha1 would
427          * get confused.
428          */
429         if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
430                 ofs = 5;
431         return append_ref(refname + ofs, sha1, 0);
432 }
433
434 static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
435 {
436         if (prefixcmp(refname, "refs/tags/"))
437                 return 0;
438         return append_ref(refname + 5, sha1, 0);
439 }
440
441 static const char *match_ref_pattern = NULL;
442 static int match_ref_slash = 0;
443 static int count_slash(const char *s)
444 {
445         int cnt = 0;
446         while (*s)
447                 if (*s++ == '/')
448                         cnt++;
449         return cnt;
450 }
451
452 static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
453 {
454         /* we want to allow pattern hold/<asterisk> to show all
455          * branches under refs/heads/hold/, and v0.99.9? to show
456          * refs/tags/v0.99.9a and friends.
457          */
458         const char *tail;
459         int slash = count_slash(refname);
460         for (tail = refname; *tail && match_ref_slash < slash; )
461                 if (*tail++ == '/')
462                         slash--;
463         if (!*tail)
464                 return 0;
465         if (fnmatch(match_ref_pattern, tail, 0))
466                 return 0;
467         if (!prefixcmp(refname, "refs/heads/"))
468                 return append_head_ref(refname, sha1, flag, cb_data);
469         if (!prefixcmp(refname, "refs/tags/"))
470                 return append_tag_ref(refname, sha1, flag, cb_data);
471         return append_ref(refname, sha1, 0);
472 }
473
474 static void snarf_refs(int head, int remotes)
475 {
476         if (head) {
477                 int orig_cnt = ref_name_cnt;
478                 for_each_ref(append_head_ref, NULL);
479                 sort_ref_range(orig_cnt, ref_name_cnt);
480         }
481         if (remotes) {
482                 int orig_cnt = ref_name_cnt;
483                 for_each_ref(append_remote_ref, NULL);
484                 sort_ref_range(orig_cnt, ref_name_cnt);
485         }
486 }
487
488 static int rev_is_head(char *head, int headlen, char *name,
489                        unsigned char *head_sha1, unsigned char *sha1)
490 {
491         if ((!head[0]) ||
492             (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
493                 return 0;
494         if (!prefixcmp(head, "refs/heads/"))
495                 head += 11;
496         if (!prefixcmp(name, "refs/heads/"))
497                 name += 11;
498         else if (!prefixcmp(name, "heads/"))
499                 name += 6;
500         return !strcmp(head, name);
501 }
502
503 static int show_merge_base(struct commit_list *seen, int num_rev)
504 {
505         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
506         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
507         int exit_status = 1;
508
509         while (seen) {
510                 struct commit *commit = pop_one_commit(&seen);
511                 int flags = commit->object.flags & all_mask;
512                 if (!(flags & UNINTERESTING) &&
513                     ((flags & all_revs) == all_revs)) {
514                         puts(sha1_to_hex(commit->object.sha1));
515                         exit_status = 0;
516                         commit->object.flags |= UNINTERESTING;
517                 }
518         }
519         return exit_status;
520 }
521
522 static int show_independent(struct commit **rev,
523                             int num_rev,
524                             char **ref_name,
525                             unsigned int *rev_mask)
526 {
527         int i;
528
529         for (i = 0; i < num_rev; i++) {
530                 struct commit *commit = rev[i];
531                 unsigned int flag = rev_mask[i];
532
533                 if (commit->object.flags == flag)
534                         puts(sha1_to_hex(commit->object.sha1));
535                 commit->object.flags |= UNINTERESTING;
536         }
537         return 0;
538 }
539
540 static void append_one_rev(const char *av)
541 {
542         unsigned char revkey[20];
543         if (!get_sha1(av, revkey)) {
544                 append_ref(av, revkey, 0);
545                 return;
546         }
547         if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
548                 /* glob style match */
549                 int saved_matches = ref_name_cnt;
550                 match_ref_pattern = av;
551                 match_ref_slash = count_slash(av);
552                 for_each_ref(append_matching_ref, NULL);
553                 if (saved_matches == ref_name_cnt &&
554                     ref_name_cnt < MAX_REVS)
555                         error("no matching refs with %s", av);
556                 if (saved_matches + 1 < ref_name_cnt)
557                         sort_ref_range(saved_matches, ref_name_cnt);
558                 return;
559         }
560         die("bad sha1 reference %s", av);
561 }
562
563 static int git_show_branch_config(const char *var, const char *value, void *cb)
564 {
565         if (!strcmp(var, "showbranch.default")) {
566                 if (!value)
567                         return config_error_nonbool(var);
568                 /*
569                  * default_arg is now passed to parse_options(), so we need to
570                  * mimick the real argv a bit better.
571                  */
572                 if (!default_num) {
573                         default_alloc = 20;
574                         default_arg = xcalloc(default_alloc, sizeof(*default_arg));
575                         default_arg[default_num++] = "show-branch";
576                 } else if (default_alloc <= default_num + 1) {
577                         default_alloc = default_alloc * 3 / 2 + 20;
578                         default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
579                 }
580                 default_arg[default_num++] = xstrdup(value);
581                 default_arg[default_num] = NULL;
582                 return 0;
583         }
584
585         if (!strcmp(var, "color.showbranch")) {
586                 showbranch_use_color = git_config_colorbool(var, value, -1);
587                 return 0;
588         }
589
590         return git_color_default_config(var, value, cb);
591 }
592
593 static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
594 {
595         /* If the commit is tip of the named branches, do not
596          * omit it.
597          * Otherwise, if it is a merge that is reachable from only one
598          * tip, it is not that interesting.
599          */
600         int i, flag, count;
601         for (i = 0; i < n; i++)
602                 if (rev[i] == commit)
603                         return 0;
604         flag = commit->object.flags;
605         for (i = count = 0; i < n; i++) {
606                 if (flag & (1u << (i + REV_SHIFT)))
607                         count++;
608         }
609         if (count == 1)
610                 return 1;
611         return 0;
612 }
613
614 static int reflog = 0;
615
616 static int parse_reflog_param(const struct option *opt, const char *arg,
617                               int unset)
618 {
619         char *ep;
620         const char **base = (const char **)opt->value;
621         if (!arg)
622                 arg = "";
623         reflog = strtoul(arg, &ep, 10);
624         if (*ep == ',')
625                 *base = ep + 1;
626         else if (*ep)
627                 return error("unrecognized reflog param '%s'", arg);
628         else
629                 *base = NULL;
630         if (reflog <= 0)
631                 reflog = DEFAULT_REFLOG;
632         return 0;
633 }
634
635 int cmd_show_branch(int ac, const char **av, const char *prefix)
636 {
637         struct commit *rev[MAX_REVS], *commit;
638         char *reflog_msg[MAX_REVS];
639         struct commit_list *list = NULL, *seen = NULL;
640         unsigned int rev_mask[MAX_REVS];
641         int num_rev, i, extra = 0;
642         int all_heads = 0, all_remotes = 0;
643         int all_mask, all_revs;
644         int lifo = 1;
645         char head[128];
646         const char *head_p;
647         int head_len;
648         unsigned char head_sha1[20];
649         int merge_base = 0;
650         int independent = 0;
651         int no_name = 0;
652         int sha1_name = 0;
653         int shown_merge_point = 0;
654         int with_current_branch = 0;
655         int head_at = -1;
656         int topics = 0;
657         int dense = 1;
658         const char *reflog_base = NULL;
659         struct option builtin_show_branch_options[] = {
660                 OPT_BOOLEAN('a', "all", &all_heads,
661                             "show remote-tracking and local branches"),
662                 OPT_BOOLEAN('r', "remotes", &all_remotes,
663                             "show remote-tracking branches"),
664                 OPT_BOOLEAN(0, "color", &showbranch_use_color,
665                             "color '*!+-' corresponding to the branch"),
666                 { OPTION_INTEGER, 0, "more", &extra, "n",
667                             "show <n> more commits after the common ancestor",
668                             PARSE_OPT_OPTARG, NULL, (intptr_t)1 },
669                 OPT_SET_INT(0, "list", &extra, "synonym to more=-1", -1),
670                 OPT_BOOLEAN(0, "no-name", &no_name, "suppress naming strings"),
671                 OPT_BOOLEAN(0, "current", &with_current_branch,
672                             "include the current branch"),
673                 OPT_BOOLEAN(0, "sha1-name", &sha1_name,
674                             "name commits with their object names"),
675                 OPT_BOOLEAN(0, "merge-base", &merge_base,
676                             "show possible merge bases"),
677                 OPT_BOOLEAN(0, "independent", &independent,
678                             "show refs unreachable from any other ref"),
679                 OPT_BOOLEAN(0, "topo-order", &lifo,
680                             "show commits in topological order"),
681                 OPT_BOOLEAN(0, "topics", &topics,
682                             "show only commits not on the first branch"),
683                 OPT_SET_INT(0, "sparse", &dense,
684                             "show merges reachable from only one tip", 0),
685                 OPT_SET_INT(0, "date-order", &lifo,
686                             "show commits where no parent comes before its "
687                             "children", 0),
688                 { OPTION_CALLBACK, 'g', "reflog", &reflog_base, "<n>[,<base>]",
689                             "show <n> most recent ref-log entries starting at "
690                             "base",
691                             PARSE_OPT_OPTARG | PARSE_OPT_LITERAL_ARGHELP,
692                             parse_reflog_param },
693                 OPT_END()
694         };
695
696         git_config(git_show_branch_config, NULL);
697
698         if (showbranch_use_color == -1)
699                 showbranch_use_color = git_use_color_default;
700
701         /* If nothing is specified, try the default first */
702         if (ac == 1 && default_num) {
703                 ac = default_num;
704                 av = default_arg;
705         }
706
707         ac = parse_options(ac, av, prefix, builtin_show_branch_options,
708                            show_branch_usage, PARSE_OPT_STOP_AT_NON_OPTION);
709         if (all_heads)
710                 all_remotes = 1;
711
712         if (extra || reflog) {
713                 /* "listing" mode is incompatible with
714                  * independent nor merge-base modes.
715                  */
716                 if (independent || merge_base)
717                         usage_with_options(show_branch_usage,
718                                            builtin_show_branch_options);
719                 if (reflog && ((0 < extra) || all_heads || all_remotes))
720                         /*
721                          * Asking for --more in reflog mode does not
722                          * make sense.  --list is Ok.
723                          *
724                          * Also --all and --remotes do not make sense either.
725                          */
726                         die("--reflog is incompatible with --all, --remotes, "
727                             "--independent or --merge-base");
728         }
729
730         /* If nothing is specified, show all branches by default */
731         if (ac + all_heads + all_remotes == 0)
732                 all_heads = 1;
733
734         if (reflog) {
735                 unsigned char sha1[20];
736                 char nth_desc[256];
737                 char *ref;
738                 int base = 0;
739
740                 if (ac == 0) {
741                         static const char *fake_av[2];
742                         const char *refname;
743
744                         refname = resolve_ref("HEAD", sha1, 1, NULL);
745                         fake_av[0] = xstrdup(refname);
746                         fake_av[1] = NULL;
747                         av = fake_av;
748                         ac = 1;
749                 }
750                 if (ac != 1)
751                         die("--reflog option needs one branch name");
752
753                 if (MAX_REVS < reflog)
754                         die("Only %d entries can be shown at one time.",
755                             MAX_REVS);
756                 if (!dwim_ref(*av, strlen(*av), sha1, &ref))
757                         die("No such ref %s", *av);
758
759                 /* Has the base been specified? */
760                 if (reflog_base) {
761                         char *ep;
762                         base = strtoul(reflog_base, &ep, 10);
763                         if (*ep) {
764                                 /* Ah, that is a date spec... */
765                                 unsigned long at;
766                                 at = approxidate(reflog_base);
767                                 read_ref_at(ref, at, -1, sha1, NULL,
768                                             NULL, NULL, &base);
769                         }
770                 }
771
772                 for (i = 0; i < reflog; i++) {
773                         char *logmsg, *m;
774                         const char *msg;
775                         unsigned long timestamp;
776                         int tz;
777
778                         if (read_ref_at(ref, 0, base+i, sha1, &logmsg,
779                                         &timestamp, &tz, NULL)) {
780                                 reflog = i;
781                                 break;
782                         }
783                         msg = strchr(logmsg, '\t');
784                         if (!msg)
785                                 msg = "(none)";
786                         else
787                                 msg++;
788                         m = xmalloc(strlen(msg) + 200);
789                         sprintf(m, "(%s) %s",
790                                 show_date(timestamp, tz, 1),
791                                 msg);
792                         reflog_msg[i] = m;
793                         free(logmsg);
794                         sprintf(nth_desc, "%s@{%d}", *av, base+i);
795                         append_ref(nth_desc, sha1, 1);
796                 }
797         }
798         else if (all_heads + all_remotes)
799                 snarf_refs(all_heads, all_remotes);
800         else {
801                 while (0 < ac) {
802                         append_one_rev(*av);
803                         ac--; av++;
804                 }
805         }
806
807         head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
808         if (head_p) {
809                 head_len = strlen(head_p);
810                 memcpy(head, head_p, head_len + 1);
811         }
812         else {
813                 head_len = 0;
814                 head[0] = 0;
815         }
816
817         if (with_current_branch && head_p) {
818                 int has_head = 0;
819                 for (i = 0; !has_head && i < ref_name_cnt; i++) {
820                         /* We are only interested in adding the branch
821                          * HEAD points at.
822                          */
823                         if (rev_is_head(head,
824                                         head_len,
825                                         ref_name[i],
826                                         head_sha1, NULL))
827                                 has_head++;
828                 }
829                 if (!has_head) {
830                         int offset = !prefixcmp(head, "refs/heads/") ? 11 : 0;
831                         append_one_rev(head + offset);
832                 }
833         }
834
835         if (!ref_name_cnt) {
836                 fprintf(stderr, "No revs to be shown.\n");
837                 exit(0);
838         }
839
840         for (num_rev = 0; ref_name[num_rev]; num_rev++) {
841                 unsigned char revkey[20];
842                 unsigned int flag = 1u << (num_rev + REV_SHIFT);
843
844                 if (MAX_REVS <= num_rev)
845                         die("cannot handle more than %d revs.", MAX_REVS);
846                 if (get_sha1(ref_name[num_rev], revkey))
847                         die("'%s' is not a valid ref.", ref_name[num_rev]);
848                 commit = lookup_commit_reference(revkey);
849                 if (!commit)
850                         die("cannot find commit %s (%s)",
851                             ref_name[num_rev], revkey);
852                 parse_commit(commit);
853                 mark_seen(commit, &seen);
854
855                 /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
856                  * and so on.  REV_SHIFT bits from bit 0 are used for
857                  * internal bookkeeping.
858                  */
859                 commit->object.flags |= flag;
860                 if (commit->object.flags == flag)
861                         insert_by_date(commit, &list);
862                 rev[num_rev] = commit;
863         }
864         for (i = 0; i < num_rev; i++)
865                 rev_mask[i] = rev[i]->object.flags;
866
867         if (0 <= extra)
868                 join_revs(&list, &seen, num_rev, extra);
869
870         sort_by_date(&seen);
871
872         if (merge_base)
873                 return show_merge_base(seen, num_rev);
874
875         if (independent)
876                 return show_independent(rev, num_rev, ref_name, rev_mask);
877
878         /* Show list; --more=-1 means list-only */
879         if (1 < num_rev || extra < 0) {
880                 for (i = 0; i < num_rev; i++) {
881                         int j;
882                         int is_head = rev_is_head(head,
883                                                   head_len,
884                                                   ref_name[i],
885                                                   head_sha1,
886                                                   rev[i]->object.sha1);
887                         if (extra < 0)
888                                 printf("%c [%s] ",
889                                        is_head ? '*' : ' ', ref_name[i]);
890                         else {
891                                 for (j = 0; j < i; j++)
892                                         putchar(' ');
893                                 printf("%s%c%s [%s] ",
894                                        get_color_code(i % COLUMN_COLORS_MAX),
895                                        is_head ? '*' : '!',
896                                        get_color_reset_code(), ref_name[i]);
897                         }
898
899                         if (!reflog) {
900                                 /* header lines never need name */
901                                 show_one_commit(rev[i], 1);
902                         }
903                         else
904                                 puts(reflog_msg[i]);
905
906                         if (is_head)
907                                 head_at = i;
908                 }
909                 if (0 <= extra) {
910                         for (i = 0; i < num_rev; i++)
911                                 putchar('-');
912                         putchar('\n');
913                 }
914         }
915         if (extra < 0)
916                 exit(0);
917
918         /* Sort topologically */
919         sort_in_topological_order(&seen, lifo);
920
921         /* Give names to commits */
922         if (!sha1_name && !no_name)
923                 name_commits(seen, rev, ref_name, num_rev);
924
925         all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
926         all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
927
928         while (seen) {
929                 struct commit *commit = pop_one_commit(&seen);
930                 int this_flag = commit->object.flags;
931                 int is_merge_point = ((this_flag & all_revs) == all_revs);
932
933                 shown_merge_point |= is_merge_point;
934
935                 if (1 < num_rev) {
936                         int is_merge = !!(commit->parents &&
937                                           commit->parents->next);
938                         if (topics &&
939                             !is_merge_point &&
940                             (this_flag & (1u << REV_SHIFT)))
941                                 continue;
942                         if (dense && is_merge &&
943                             omit_in_dense(commit, rev, num_rev))
944                                 continue;
945                         for (i = 0; i < num_rev; i++) {
946                                 int mark;
947                                 if (!(this_flag & (1u << (i + REV_SHIFT))))
948                                         mark = ' ';
949                                 else if (is_merge)
950                                         mark = '-';
951                                 else if (i == head_at)
952                                         mark = '*';
953                                 else
954                                         mark = '+';
955                                 printf("%s%c%s",
956                                        get_color_code(i % COLUMN_COLORS_MAX),
957                                        mark, get_color_reset_code());
958                         }
959                         putchar(' ');
960                 }
961                 show_one_commit(commit, no_name);
962
963                 if (shown_merge_point && --extra < 0)
964                         break;
965         }
966         return 0;
967 }