Shrink "struct object" a bit
[git/git.git] / builtin-show-branch.c
1 #include <stdlib.h>
2 #include <fnmatch.h>
3 #include "cache.h"
4 #include "commit.h"
5 #include "refs.h"
6 #include "builtin.h"
7
8 static const char show_branch_usage[] =
9 "git-show-branch [--dense] [--current] [--all] [--heads] [--tags] [--topo-order] [--more=count | --list | --independent | --merge-base ] [--topics] [<refs>...]";
10
11 static int default_num = 0;
12 static int default_alloc = 0;
13 static const char **default_arg = NULL;
14
15 #define UNINTERESTING 01
16
17 #define REV_SHIFT 2
18 #define MAX_REVS (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
19
20 static struct commit *interesting(struct commit_list *list)
21 {
22 while (list) {
23 struct commit *commit = list->item;
24 list = list->next;
25 if (commit->object.flags & UNINTERESTING)
26 continue;
27 return commit;
28 }
29 return NULL;
30 }
31
32 static struct commit *pop_one_commit(struct commit_list **list_p)
33 {
34 struct commit *commit;
35 struct commit_list *list;
36 list = *list_p;
37 commit = list->item;
38 *list_p = list->next;
39 free(list);
40 return commit;
41 }
42
43 struct commit_name {
44 const char *head_name; /* which head's ancestor? */
45 int generation; /* how many parents away from head_name */
46 };
47
48 /* Name the commit as nth generation ancestor of head_name;
49 * we count only the first-parent relationship for naming purposes.
50 */
51 static void name_commit(struct commit *commit, const char *head_name, int nth)
52 {
53 struct commit_name *name;
54 if (!commit->object.util)
55 commit->object.util = xmalloc(sizeof(struct commit_name));
56 name = commit->object.util;
57 name->head_name = head_name;
58 name->generation = nth;
59 }
60
61 /* Parent is the first parent of the commit. We may name it
62 * as (n+1)th generation ancestor of the same head_name as
63 * commit is nth generation ancestor of, if that generation
64 * number is better than the name it already has.
65 */
66 static void name_parent(struct commit *commit, struct commit *parent)
67 {
68 struct commit_name *commit_name = commit->object.util;
69 struct commit_name *parent_name = parent->object.util;
70 if (!commit_name)
71 return;
72 if (!parent_name ||
73 commit_name->generation + 1 < parent_name->generation)
74 name_commit(parent, commit_name->head_name,
75 commit_name->generation + 1);
76 }
77
78 static int name_first_parent_chain(struct commit *c)
79 {
80 int i = 0;
81 while (c) {
82 struct commit *p;
83 if (!c->object.util)
84 break;
85 if (!c->parents)
86 break;
87 p = c->parents->item;
88 if (!p->object.util) {
89 name_parent(c, p);
90 i++;
91 }
92 c = p;
93 }
94 return i;
95 }
96
97 static void name_commits(struct commit_list *list,
98 struct commit **rev,
99 char **ref_name,
100 int num_rev)
101 {
102 struct commit_list *cl;
103 struct commit *c;
104 int i;
105
106 /* First give names to the given heads */
107 for (cl = list; cl; cl = cl->next) {
108 c = cl->item;
109 if (c->object.util)
110 continue;
111 for (i = 0; i < num_rev; i++) {
112 if (rev[i] == c) {
113 name_commit(c, ref_name[i], 0);
114 break;
115 }
116 }
117 }
118
119 /* Then commits on the first parent ancestry chain */
120 do {
121 i = 0;
122 for (cl = list; cl; cl = cl->next) {
123 i += name_first_parent_chain(cl->item);
124 }
125 } while (i);
126
127 /* Finally, any unnamed commits */
128 do {
129 i = 0;
130 for (cl = list; cl; cl = cl->next) {
131 struct commit_list *parents;
132 struct commit_name *n;
133 int nth;
134 c = cl->item;
135 if (!c->object.util)
136 continue;
137 n = c->object.util;
138 parents = c->parents;
139 nth = 0;
140 while (parents) {
141 struct commit *p = parents->item;
142 char newname[1000], *en;
143 parents = parents->next;
144 nth++;
145 if (p->object.util)
146 continue;
147 en = newname;
148 switch (n->generation) {
149 case 0:
150 en += sprintf(en, "%s", n->head_name);
151 break;
152 case 1:
153 en += sprintf(en, "%s^", n->head_name);
154 break;
155 default:
156 en += sprintf(en, "%s~%d",
157 n->head_name, n->generation);
158 break;
159 }
160 if (nth == 1)
161 en += sprintf(en, "^");
162 else
163 en += sprintf(en, "^%d", nth);
164 name_commit(p, strdup(newname), 0);
165 i++;
166 name_first_parent_chain(p);
167 }
168 }
169 } while (i);
170 }
171
172 static int mark_seen(struct commit *commit, struct commit_list **seen_p)
173 {
174 if (!commit->object.flags) {
175 insert_by_date(commit, seen_p);
176 return 1;
177 }
178 return 0;
179 }
180
181 static void join_revs(struct commit_list **list_p,
182 struct commit_list **seen_p,
183 int num_rev, int extra)
184 {
185 int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
186 int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
187
188 while (*list_p) {
189 struct commit_list *parents;
190 int still_interesting = !!interesting(*list_p);
191 struct commit *commit = pop_one_commit(list_p);
192 int flags = commit->object.flags & all_mask;
193
194 if (!still_interesting && extra <= 0)
195 break;
196
197 mark_seen(commit, seen_p);
198 if ((flags & all_revs) == all_revs)
199 flags |= UNINTERESTING;
200 parents = commit->parents;
201
202 while (parents) {
203 struct commit *p = parents->item;
204 int this_flag = p->object.flags;
205 parents = parents->next;
206 if ((this_flag & flags) == flags)
207 continue;
208 if (!p->object.parsed)
209 parse_commit(p);
210 if (mark_seen(p, seen_p) && !still_interesting)
211 extra--;
212 p->object.flags |= flags;
213 insert_by_date(p, list_p);
214 }
215 }
216
217 /*
218 * Postprocess to complete well-poisoning.
219 *
220 * At this point we have all the commits we have seen in
221 * seen_p list (which happens to be sorted chronologically but
222 * it does not really matter). Mark anything that can be
223 * reached from uninteresting commits not interesting.
224 */
225 for (;;) {
226 int changed = 0;
227 struct commit_list *s;
228 for (s = *seen_p; s; s = s->next) {
229 struct commit *c = s->item;
230 struct commit_list *parents;
231
232 if (((c->object.flags & all_revs) != all_revs) &&
233 !(c->object.flags & UNINTERESTING))
234 continue;
235
236 /* The current commit is either a merge base or
237 * already uninteresting one. Mark its parents
238 * as uninteresting commits _only_ if they are
239 * already parsed. No reason to find new ones
240 * here.
241 */
242 parents = c->parents;
243 while (parents) {
244 struct commit *p = parents->item;
245 parents = parents->next;
246 if (!(p->object.flags & UNINTERESTING)) {
247 p->object.flags |= UNINTERESTING;
248 changed = 1;
249 }
250 }
251 }
252 if (!changed)
253 break;
254 }
255 }
256
257 static void show_one_commit(struct commit *commit, int no_name)
258 {
259 char pretty[256], *cp;
260 struct commit_name *name = commit->object.util;
261 if (commit->object.parsed)
262 pretty_print_commit(CMIT_FMT_ONELINE, commit, ~0,
263 pretty, sizeof(pretty), 0, NULL, NULL);
264 else
265 strcpy(pretty, "(unavailable)");
266 if (!strncmp(pretty, "[PATCH] ", 8))
267 cp = pretty + 8;
268 else
269 cp = pretty;
270
271 if (!no_name) {
272 if (name && name->head_name) {
273 printf("[%s", name->head_name);
274 if (name->generation) {
275 if (name->generation == 1)
276 printf("^");
277 else
278 printf("~%d", name->generation);
279 }
280 printf("] ");
281 }
282 else
283 printf("[%s] ",
284 find_unique_abbrev(commit->object.sha1, 7));
285 }
286 puts(cp);
287 }
288
289 static char *ref_name[MAX_REVS + 1];
290 static int ref_name_cnt;
291
292 static const char *find_digit_prefix(const char *s, int *v)
293 {
294 const char *p;
295 int ver;
296 char ch;
297
298 for (p = s, ver = 0;
299 '0' <= (ch = *p) && ch <= '9';
300 p++)
301 ver = ver * 10 + ch - '0';
302 *v = ver;
303 return p;
304 }
305
306
307 static int version_cmp(const char *a, const char *b)
308 {
309 while (1) {
310 int va, vb;
311
312 a = find_digit_prefix(a, &va);
313 b = find_digit_prefix(b, &vb);
314 if (va != vb)
315 return va - vb;
316
317 while (1) {
318 int ca = *a;
319 int cb = *b;
320 if ('0' <= ca && ca <= '9')
321 ca = 0;
322 if ('0' <= cb && cb <= '9')
323 cb = 0;
324 if (ca != cb)
325 return ca - cb;
326 if (!ca)
327 break;
328 a++;
329 b++;
330 }
331 if (!*a && !*b)
332 return 0;
333 }
334 }
335
336 static int compare_ref_name(const void *a_, const void *b_)
337 {
338 const char * const*a = a_, * const*b = b_;
339 return version_cmp(*a, *b);
340 }
341
342 static void sort_ref_range(int bottom, int top)
343 {
344 qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
345 compare_ref_name);
346 }
347
348 static int append_ref(const char *refname, const unsigned char *sha1)
349 {
350 struct commit *commit = lookup_commit_reference_gently(sha1, 1);
351 int i;
352
353 if (!commit)
354 return 0;
355 /* Avoid adding the same thing twice */
356 for (i = 0; i < ref_name_cnt; i++)
357 if (!strcmp(refname, ref_name[i]))
358 return 0;
359
360 if (MAX_REVS <= ref_name_cnt) {
361 fprintf(stderr, "warning: ignoring %s; "
362 "cannot handle more than %d refs\n",
363 refname, MAX_REVS);
364 return 0;
365 }
366 ref_name[ref_name_cnt++] = strdup(refname);
367 ref_name[ref_name_cnt] = NULL;
368 return 0;
369 }
370
371 static int append_head_ref(const char *refname, const unsigned char *sha1)
372 {
373 unsigned char tmp[20];
374 int ofs = 11;
375 if (strncmp(refname, "refs/heads/", ofs))
376 return 0;
377 /* If both heads/foo and tags/foo exists, get_sha1 would
378 * get confused.
379 */
380 if (get_sha1(refname + ofs, tmp) || memcmp(tmp, sha1, 20))
381 ofs = 5;
382 return append_ref(refname + ofs, sha1);
383 }
384
385 static int append_tag_ref(const char *refname, const unsigned char *sha1)
386 {
387 if (strncmp(refname, "refs/tags/", 10))
388 return 0;
389 return append_ref(refname + 5, sha1);
390 }
391
392 static const char *match_ref_pattern = NULL;
393 static int match_ref_slash = 0;
394 static int count_slash(const char *s)
395 {
396 int cnt = 0;
397 while (*s)
398 if (*s++ == '/')
399 cnt++;
400 return cnt;
401 }
402
403 static int append_matching_ref(const char *refname, const unsigned char *sha1)
404 {
405 /* we want to allow pattern hold/<asterisk> to show all
406 * branches under refs/heads/hold/, and v0.99.9? to show
407 * refs/tags/v0.99.9a and friends.
408 */
409 const char *tail;
410 int slash = count_slash(refname);
411 for (tail = refname; *tail && match_ref_slash < slash; )
412 if (*tail++ == '/')
413 slash--;
414 if (!*tail)
415 return 0;
416 if (fnmatch(match_ref_pattern, tail, 0))
417 return 0;
418 if (!strncmp("refs/heads/", refname, 11))
419 return append_head_ref(refname, sha1);
420 if (!strncmp("refs/tags/", refname, 10))
421 return append_tag_ref(refname, sha1);
422 return append_ref(refname, sha1);
423 }
424
425 static void snarf_refs(int head, int tag)
426 {
427 if (head) {
428 int orig_cnt = ref_name_cnt;
429 for_each_ref(append_head_ref);
430 sort_ref_range(orig_cnt, ref_name_cnt);
431 }
432 if (tag) {
433 int orig_cnt = ref_name_cnt;
434 for_each_ref(append_tag_ref);
435 sort_ref_range(orig_cnt, ref_name_cnt);
436 }
437 }
438
439 static int rev_is_head(char *head_path, int headlen, char *name,
440 unsigned char *head_sha1, unsigned char *sha1)
441 {
442 int namelen;
443 if ((!head_path[0]) ||
444 (head_sha1 && sha1 && memcmp(head_sha1, sha1, 20)))
445 return 0;
446 namelen = strlen(name);
447 if ((headlen < namelen) ||
448 memcmp(head_path + headlen - namelen, name, namelen))
449 return 0;
450 if (headlen == namelen ||
451 head_path[headlen - namelen - 1] == '/')
452 return 1;
453 return 0;
454 }
455
456 static int show_merge_base(struct commit_list *seen, int num_rev)
457 {
458 int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
459 int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
460 int exit_status = 1;
461
462 while (seen) {
463 struct commit *commit = pop_one_commit(&seen);
464 int flags = commit->object.flags & all_mask;
465 if (!(flags & UNINTERESTING) &&
466 ((flags & all_revs) == all_revs)) {
467 puts(sha1_to_hex(commit->object.sha1));
468 exit_status = 0;
469 commit->object.flags |= UNINTERESTING;
470 }
471 }
472 return exit_status;
473 }
474
475 static int show_independent(struct commit **rev,
476 int num_rev,
477 char **ref_name,
478 unsigned int *rev_mask)
479 {
480 int i;
481
482 for (i = 0; i < num_rev; i++) {
483 struct commit *commit = rev[i];
484 unsigned int flag = rev_mask[i];
485
486 if (commit->object.flags == flag)
487 puts(sha1_to_hex(commit->object.sha1));
488 commit->object.flags |= UNINTERESTING;
489 }
490 return 0;
491 }
492
493 static void append_one_rev(const char *av)
494 {
495 unsigned char revkey[20];
496 if (!get_sha1(av, revkey)) {
497 append_ref(av, revkey);
498 return;
499 }
500 if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
501 /* glob style match */
502 int saved_matches = ref_name_cnt;
503 match_ref_pattern = av;
504 match_ref_slash = count_slash(av);
505 for_each_ref(append_matching_ref);
506 if (saved_matches == ref_name_cnt &&
507 ref_name_cnt < MAX_REVS)
508 error("no matching refs with %s", av);
509 if (saved_matches + 1 < ref_name_cnt)
510 sort_ref_range(saved_matches, ref_name_cnt);
511 return;
512 }
513 die("bad sha1 reference %s", av);
514 }
515
516 static int git_show_branch_config(const char *var, const char *value)
517 {
518 if (!strcmp(var, "showbranch.default")) {
519 if (default_alloc <= default_num + 1) {
520 default_alloc = default_alloc * 3 / 2 + 20;
521 default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
522 }
523 default_arg[default_num++] = strdup(value);
524 default_arg[default_num] = NULL;
525 return 0;
526 }
527
528 return git_default_config(var, value);
529 }
530
531 static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
532 {
533 /* If the commit is tip of the named branches, do not
534 * omit it.
535 * Otherwise, if it is a merge that is reachable from only one
536 * tip, it is not that interesting.
537 */
538 int i, flag, count;
539 for (i = 0; i < n; i++)
540 if (rev[i] == commit)
541 return 0;
542 flag = commit->object.flags;
543 for (i = count = 0; i < n; i++) {
544 if (flag & (1u << (i + REV_SHIFT)))
545 count++;
546 }
547 if (count == 1)
548 return 1;
549 return 0;
550 }
551
552 int cmd_show_branch(int ac, const char **av, char **envp)
553 {
554 struct commit *rev[MAX_REVS], *commit;
555 struct commit_list *list = NULL, *seen = NULL;
556 unsigned int rev_mask[MAX_REVS];
557 int num_rev, i, extra = 0;
558 int all_heads = 0, all_tags = 0;
559 int all_mask, all_revs;
560 int lifo = 1;
561 char head_path[128];
562 const char *head_path_p;
563 int head_path_len;
564 unsigned char head_sha1[20];
565 int merge_base = 0;
566 int independent = 0;
567 int no_name = 0;
568 int sha1_name = 0;
569 int shown_merge_point = 0;
570 int with_current_branch = 0;
571 int head_at = -1;
572 int topics = 0;
573 int dense = 1;
574
575 setup_git_directory();
576 git_config(git_show_branch_config);
577
578 /* If nothing is specified, try the default first */
579 if (ac == 1 && default_num) {
580 ac = default_num + 1;
581 av = default_arg - 1; /* ick; we would not address av[0] */
582 }
583
584 while (1 < ac && av[1][0] == '-') {
585 const char *arg = av[1];
586 if (!strcmp(arg, "--")) {
587 ac--; av++;
588 break;
589 }
590 else if (!strcmp(arg, "--all"))
591 all_heads = all_tags = 1;
592 else if (!strcmp(arg, "--heads"))
593 all_heads = 1;
594 else if (!strcmp(arg, "--tags"))
595 all_tags = 1;
596 else if (!strcmp(arg, "--more"))
597 extra = 1;
598 else if (!strcmp(arg, "--list"))
599 extra = -1;
600 else if (!strcmp(arg, "--no-name"))
601 no_name = 1;
602 else if (!strcmp(arg, "--current"))
603 with_current_branch = 1;
604 else if (!strcmp(arg, "--sha1-name"))
605 sha1_name = 1;
606 else if (!strncmp(arg, "--more=", 7))
607 extra = atoi(arg + 7);
608 else if (!strcmp(arg, "--merge-base"))
609 merge_base = 1;
610 else if (!strcmp(arg, "--independent"))
611 independent = 1;
612 else if (!strcmp(arg, "--topo-order"))
613 lifo = 1;
614 else if (!strcmp(arg, "--topics"))
615 topics = 1;
616 else if (!strcmp(arg, "--sparse"))
617 dense = 0;
618 else if (!strcmp(arg, "--date-order"))
619 lifo = 0;
620 else
621 usage(show_branch_usage);
622 ac--; av++;
623 }
624 ac--; av++;
625
626 /* Only one of these is allowed */
627 if (1 < independent + merge_base + (extra != 0))
628 usage(show_branch_usage);
629
630 /* If nothing is specified, show all branches by default */
631 if (ac + all_heads + all_tags == 0)
632 all_heads = 1;
633
634 if (all_heads + all_tags)
635 snarf_refs(all_heads, all_tags);
636 while (0 < ac) {
637 append_one_rev(*av);
638 ac--; av++;
639 }
640
641 head_path_p = resolve_ref(git_path("HEAD"), head_sha1, 1);
642 if (head_path_p) {
643 head_path_len = strlen(head_path_p);
644 memcpy(head_path, head_path_p, head_path_len + 1);
645 }
646 else {
647 head_path_len = 0;
648 head_path[0] = 0;
649 }
650
651 if (with_current_branch && head_path_p) {
652 int has_head = 0;
653 for (i = 0; !has_head && i < ref_name_cnt; i++) {
654 /* We are only interested in adding the branch
655 * HEAD points at.
656 */
657 if (rev_is_head(head_path,
658 head_path_len,
659 ref_name[i],
660 head_sha1, NULL))
661 has_head++;
662 }
663 if (!has_head) {
664 int pfxlen = strlen(git_path("refs/heads/"));
665 append_one_rev(head_path + pfxlen);
666 }
667 }
668
669 if (!ref_name_cnt) {
670 fprintf(stderr, "No revs to be shown.\n");
671 exit(0);
672 }
673
674 for (num_rev = 0; ref_name[num_rev]; num_rev++) {
675 unsigned char revkey[20];
676 unsigned int flag = 1u << (num_rev + REV_SHIFT);
677
678 if (MAX_REVS <= num_rev)
679 die("cannot handle more than %d revs.", MAX_REVS);
680 if (get_sha1(ref_name[num_rev], revkey))
681 die("'%s' is not a valid ref.", ref_name[num_rev]);
682 commit = lookup_commit_reference(revkey);
683 if (!commit)
684 die("cannot find commit %s (%s)",
685 ref_name[num_rev], revkey);
686 parse_commit(commit);
687 mark_seen(commit, &seen);
688
689 /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
690 * and so on. REV_SHIFT bits from bit 0 are used for
691 * internal bookkeeping.
692 */
693 commit->object.flags |= flag;
694 if (commit->object.flags == flag)
695 insert_by_date(commit, &list);
696 rev[num_rev] = commit;
697 }
698 for (i = 0; i < num_rev; i++)
699 rev_mask[i] = rev[i]->object.flags;
700
701 if (0 <= extra)
702 join_revs(&list, &seen, num_rev, extra);
703
704 if (merge_base)
705 return show_merge_base(seen, num_rev);
706
707 if (independent)
708 return show_independent(rev, num_rev, ref_name, rev_mask);
709
710 /* Show list; --more=-1 means list-only */
711 if (1 < num_rev || extra < 0) {
712 for (i = 0; i < num_rev; i++) {
713 int j;
714 int is_head = rev_is_head(head_path,
715 head_path_len,
716 ref_name[i],
717 head_sha1,
718 rev[i]->object.sha1);
719 if (extra < 0)
720 printf("%c [%s] ",
721 is_head ? '*' : ' ', ref_name[i]);
722 else {
723 for (j = 0; j < i; j++)
724 putchar(' ');
725 printf("%c [%s] ",
726 is_head ? '*' : '!', ref_name[i]);
727 }
728 /* header lines never need name */
729 show_one_commit(rev[i], 1);
730 if (is_head)
731 head_at = i;
732 }
733 if (0 <= extra) {
734 for (i = 0; i < num_rev; i++)
735 putchar('-');
736 putchar('\n');
737 }
738 }
739 if (extra < 0)
740 exit(0);
741
742 /* Sort topologically */
743 sort_in_topological_order(&seen, lifo);
744
745 /* Give names to commits */
746 if (!sha1_name && !no_name)
747 name_commits(seen, rev, ref_name, num_rev);
748
749 all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
750 all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
751
752 while (seen) {
753 struct commit *commit = pop_one_commit(&seen);
754 int this_flag = commit->object.flags;
755 int is_merge_point = ((this_flag & all_revs) == all_revs);
756
757 shown_merge_point |= is_merge_point;
758
759 if (1 < num_rev) {
760 int is_merge = !!(commit->parents &&
761 commit->parents->next);
762 if (topics &&
763 !is_merge_point &&
764 (this_flag & (1u << REV_SHIFT)))
765 continue;
766 if (dense && is_merge &&
767 omit_in_dense(commit, rev, num_rev))
768 continue;
769 for (i = 0; i < num_rev; i++) {
770 int mark;
771 if (!(this_flag & (1u << (i + REV_SHIFT))))
772 mark = ' ';
773 else if (is_merge)
774 mark = '-';
775 else if (i == head_at)
776 mark = '*';
777 else
778 mark = '+';
779 putchar(mark);
780 }
781 putchar(' ');
782 }
783 show_one_commit(commit, no_name);
784
785 if (shown_merge_point && --extra < 0)
786 break;
787 }
788 return 0;
789 }