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