1#include <stdlib.h>
2#include <fnmatch.h>
3#include "cache.h"
4#include "commit.h"
5#include "refs.h"
6static const char show_branch_usage[] =
8"git-show-branch [--all] [--heads] [--tags] [--more=count | --list | --independent | --merge-base ] [<refs>...]";
9#define UNINTERESTING 01
11#define REV_SHIFT 2
13#define MAX_REVS 29 /* should not exceed bits_per_int - REV_SHIFT */
14static struct commit *interesting(struct commit_list *list)
16{
17 while (list) {
18 struct commit *commit = list->item;
19 list = list->next;
20 if (commit->object.flags & UNINTERESTING)
21 continue;
22 return commit;
23 }
24 return NULL;
25}
26static struct commit *pop_one_commit(struct commit_list **list_p)
28{
29 struct commit *commit;
30 struct commit_list *list;
31 list = *list_p;
32 commit = list->item;
33 *list_p = list->next;
34 free(list);
35 return commit;
36}
37struct commit_name {
39 const char *head_name; /* which head's ancestor? */
40 int generation; /* how many parents away from head_name */
41};
42/* Name the commit as nth generation ancestor of head_name;
44 * we count only the first-parent relationship for naming purposes.
45 */
46static void name_commit(struct commit *commit, const char *head_name, int nth)
47{
48 struct commit_name *name;
49 if (!commit->object.util)
50 commit->object.util = xmalloc(sizeof(struct commit_name));
51 name = commit->object.util;
52 name->head_name = head_name;
53 name->generation = nth;
54}
55/* Parent is the first parent of the commit. We may name it
57 * as (n+1)th generation ancestor of the same head_name as
58 * commit is nth generation ancestore of, if that generation
59 * number is better than the name it already has.
60 */
61static void name_parent(struct commit *commit, struct commit *parent)
62{
63 struct commit_name *commit_name = commit->object.util;
64 struct commit_name *parent_name = parent->object.util;
65 if (!commit_name)
66 return;
67 if (!parent_name ||
68 commit_name->generation + 1 < parent_name->generation)
69 name_commit(parent, commit_name->head_name,
70 commit_name->generation + 1);
71}
72static int name_first_parent_chain(struct commit *c)
74{
75 int i = 0;
76 while (c) {
77 struct commit *p;
78 if (!c->object.util)
79 break;
80 if (!c->parents)
81 break;
82 p = c->parents->item;
83 if (!p->object.util) {
84 name_parent(c, p);
85 i++;
86 }
87 c = p;
88 }
89 return i;
90}
91static void name_commits(struct commit_list *list,
93 struct commit **rev,
94 char **ref_name,
95 int num_rev)
96{
97 struct commit_list *cl;
98 struct commit *c;
99 int i;
100 /* First give names to the given heads */
102 for (cl = list; cl; cl = cl->next) {
103 c = cl->item;
104 if (c->object.util)
105 continue;
106 for (i = 0; i < num_rev; i++) {
107 if (rev[i] == c) {
108 name_commit(c, ref_name[i], 0);
109 break;
110 }
111 }
112 }
113 /* Then commits on the first parent ancestry chain */
115 do {
116 i = 0;
117 for (cl = list; cl; cl = cl->next) {
118 i += name_first_parent_chain(cl->item);
119 }
120 } while (i);
121 /* Finally, any unnamed commits */
123 do {
124 i = 0;
125 for (cl = list; cl; cl = cl->next) {
126 struct commit_list *parents;
127 struct commit_name *n;
128 int nth;
129 c = cl->item;
130 if (!c->object.util)
131 continue;
132 n = c->object.util;
133 parents = c->parents;
134 nth = 0;
135 while (parents) {
136 struct commit *p = parents->item;
137 char newname[1000], *en;
138 parents = parents->next;
139 nth++;
140 if (p->object.util)
141 continue;
142 en = newname;
143 switch (n->generation) {
144 case 0:
145 en += sprintf(en, "%s", n->head_name);
146 break;
147 case 1:
148 en += sprintf(en, "%s^", n->head_name);
149 break;
150 default:
151 en += sprintf(en, "%s~%d",
152 n->head_name, n->generation);
153 break;
154 }
155 if (nth == 1)
156 en += sprintf(en, "^");
157 else
158 en += sprintf(en, "^%d", nth);
159 name_commit(p, strdup(newname), 0);
160 i++;
161 name_first_parent_chain(p);
162 }
163 }
164 } while (i);
165}
166static int mark_seen(struct commit *commit, struct commit_list **seen_p)
168{
169 if (!commit->object.flags) {
170 insert_by_date(commit, seen_p);
171 return 1;
172 }
173 return 0;
174}
175static void join_revs(struct commit_list **list_p,
177 struct commit_list **seen_p,
178 int num_rev, int extra)
179{
180 int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
181 int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
182 while (*list_p) {
184 struct commit_list *parents;
185 int still_interesting = !!interesting(*list_p);
186 struct commit *commit = pop_one_commit(list_p);
187 int flags = commit->object.flags & all_mask;
188 if (!still_interesting && extra <= 0)
190 break;
191 mark_seen(commit, seen_p);
193 if ((flags & all_revs) == all_revs)
194 flags |= UNINTERESTING;
195 parents = commit->parents;
196 while (parents) {
198 struct commit *p = parents->item;
199 int this_flag = p->object.flags;
200 parents = parents->next;
201 if ((this_flag & flags) == flags)
202 continue;
203 if (!p->object.parsed)
204 parse_commit(p);
205 if (mark_seen(p, seen_p) && !still_interesting)
206 extra--;
207 p->object.flags |= flags;
208 insert_by_date(p, list_p);
209 }
210 }
211 /*
213 * Postprocess to complete well-poisoning.
214 *
215 * At this point we have all the commits we have seen in
216 * seen_p list (which happens to be sorted chronologically but
217 * it does not really matter). Mark anything that can be
218 * reached from uninteresting commits not interesting.
219 */
220 for (;;) {
221 int changed = 0;
222 struct commit_list *s;
223 for (s = *seen_p; s; s = s->next) {
224 struct commit *c = s->item;
225 struct commit_list *parents;
226 if (((c->object.flags & all_revs) != all_revs) &&
228 !(c->object.flags & UNINTERESTING))
229 continue;
230 /* The current commit is either a merge base or
232 * already uninteresting one. Mark its parents
233 * as uninteresting commits _only_ if they are
234 * already parsed. No reason to find new ones
235 * here.
236 */
237 parents = c->parents;
238 while (parents) {
239 struct commit *p = parents->item;
240 parents = parents->next;
241 if (!(p->object.flags & UNINTERESTING)) {
242 p->object.flags |= UNINTERESTING;
243 changed = 1;
244 }
245 }
246 }
247 if (!changed)
248 break;
249 }
250}
251static void show_one_commit(struct commit *commit, int no_name)
253{
254 char pretty[256], *cp;
255 struct commit_name *name = commit->object.util;
256 if (commit->object.parsed)
257 pretty_print_commit(CMIT_FMT_ONELINE, commit->buffer, ~0,
258 pretty, sizeof(pretty));
259 else
260 strcpy(pretty, "(unavailable)");
261 if (!strncmp(pretty, "[PATCH] ", 8))
262 cp = pretty + 8;
263 else
264 cp = pretty;
265 if (!no_name) {
267 if (name && name->head_name) {
268 printf("[%s", name->head_name);
269 if (name->generation) {
270 if (name->generation == 1)
271 printf("^");
272 else
273 printf("~%d", name->generation);
274 }
275 printf("] ");
276 }
277 else
278 printf("[%s] ",
279 find_unique_abbrev(commit->object.sha1, 7));
280 }
281 puts(cp);
282}
283static char *ref_name[MAX_REVS + 1];
285static int ref_name_cnt;
286static int compare_ref_name(const void *a_, const void *b_)
288{
289 const char * const*a = a_, * const*b = b_;
290 return strcmp(*a, *b);
291}
292static void sort_ref_range(int bottom, int top)
294{
295 qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
296 compare_ref_name);
297}
298static int append_ref(const char *refname, const unsigned char *sha1)
300{
301 struct commit *commit = lookup_commit_reference_gently(sha1, 1);
302 if (!commit)
303 return 0;
304 if (MAX_REVS <= ref_name_cnt) {
305 fprintf(stderr, "warning: ignoring %s; "
306 "cannot handle more than %d refs",
307 refname, MAX_REVS);
308 return 0;
309 }
310 ref_name[ref_name_cnt++] = strdup(refname);
311 ref_name[ref_name_cnt] = NULL;
312 return 0;
313}
314static int append_head_ref(const char *refname, const unsigned char *sha1)
316{
317 unsigned char tmp[20];
318 int ofs = 11;
319 if (strncmp(refname, "refs/heads/", ofs))
320 return 0;
321 /* If both heads/foo and tags/foo exists, get_sha1 would
322 * get confused.
323 */
324 if (get_sha1(refname + ofs, tmp) || memcmp(tmp, sha1, 20))
325 ofs = 5;
326 return append_ref(refname + ofs, sha1);
327}
328static int append_tag_ref(const char *refname, const unsigned char *sha1)
330{
331 if (strncmp(refname, "refs/tags/", 10))
332 return 0;
333 return append_ref(refname + 5, sha1);
334}
335static const char *match_ref_pattern = NULL;
337static int match_ref_slash = 0;
338static int count_slash(const char *s)
339{
340 int cnt = 0;
341 while (*s)
342 if (*s++ == '/')
343 cnt++;
344 return cnt;
345}
346static int append_matching_ref(const char *refname, const unsigned char *sha1)
348{
349 /* we want to allow pattern hold/<asterisk> to show all
350 * branches under refs/heads/hold/, and v0.99.9? to show
351 * refs/tags/v0.99.9a and friends.
352 */
353 const char *tail;
354 int slash = count_slash(refname);
355 for (tail = refname; *tail && match_ref_slash < slash; )
356 if (*tail++ == '/')
357 slash--;
358 if (!*tail)
359 return 0;
360 if (fnmatch(match_ref_pattern, tail, 0))
361 return 0;
362 if (!strncmp("refs/heads/", refname, 11))
363 return append_head_ref(refname, sha1);
364 if (!strncmp("refs/tags/", refname, 10))
365 return append_tag_ref(refname, sha1);
366 return append_ref(refname, sha1);
367}
368static void snarf_refs(int head, int tag)
370{
371 if (head) {
372 int orig_cnt = ref_name_cnt;
373 for_each_ref(append_head_ref);
374 sort_ref_range(orig_cnt, ref_name_cnt);
375 }
376 if (tag) {
377 int orig_cnt = ref_name_cnt;
378 for_each_ref(append_tag_ref);
379 sort_ref_range(orig_cnt, ref_name_cnt);
380 }
381}
382static int rev_is_head(char *head_path, int headlen,
384 char *name,
385 unsigned char *head_sha1, unsigned char *sha1)
386{
387 int namelen;
388 if ((!head_path[0]) || memcmp(head_sha1, sha1, 20))
389 return 0;
390 namelen = strlen(name);
391 if ((headlen < namelen) ||
392 memcmp(head_path + headlen - namelen, name, namelen))
393 return 0;
394 if (headlen == namelen ||
395 head_path[headlen - namelen - 1] == '/')
396 return 1;
397 return 0;
398}
399static int show_merge_base(struct commit_list *seen, int num_rev)
401{
402 int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
403 int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
404 int exit_status = 1;
405 while (seen) {
407 struct commit *commit = pop_one_commit(&seen);
408 int flags = commit->object.flags & all_mask;
409 if (!(flags & UNINTERESTING) &&
410 ((flags & all_revs) == all_revs)) {
411 puts(sha1_to_hex(commit->object.sha1));
412 exit_status = 0;
413 commit->object.flags |= UNINTERESTING;
414 }
415 }
416 return exit_status;
417}
418static int show_independent(struct commit **rev,
420 int num_rev,
421 char **ref_name,
422 unsigned int *rev_mask)
423{
424 int i;
425 for (i = 0; i < num_rev; i++) {
427 struct commit *commit = rev[i];
428 unsigned int flag = rev_mask[i];
429 if (commit->object.flags == flag)
431 puts(sha1_to_hex(commit->object.sha1));
432 commit->object.flags |= UNINTERESTING;
433 }
434 return 0;
435}
436static void append_one_rev(const char *av)
438{
439 unsigned char revkey[20];
440 if (!get_sha1(av, revkey)) {
441 append_ref(av, revkey);
442 return;
443 }
444 if (strchr(av, '*') || strchr(av, '?')) {
445 /* glob style match */
446 int saved_matches = ref_name_cnt;
447 match_ref_pattern = av;
448 match_ref_slash = count_slash(av);
449 for_each_ref(append_matching_ref);
450 if (saved_matches == ref_name_cnt &&
451 ref_name_cnt < MAX_REVS)
452 error("no matching refs with %s", av);
453 return;
454 }
455 die("bad sha1 reference %s", av);
456}
457int main(int ac, char **av)
459{
460 struct commit *rev[MAX_REVS], *commit;
461 struct commit_list *list = NULL, *seen = NULL;
462 unsigned int rev_mask[MAX_REVS];
463 int num_rev, i, extra = 0;
464 int all_heads = 0, all_tags = 0;
465 int all_mask, all_revs;
466 char head_path[128];
467 const char *head_path_p;
468 int head_path_len;
469 unsigned char head_sha1[20];
470 int merge_base = 0;
471 int independent = 0;
472 int no_name = 0;
473 int sha1_name = 0;
474 int shown_merge_point = 0;
475 int topo_order = 0;
476 setup_git_directory();
478 while (1 < ac && av[1][0] == '-') {
480 char *arg = av[1];
481 if (!strcmp(arg, "--all"))
482 all_heads = all_tags = 1;
483 else if (!strcmp(arg, "--heads"))
484 all_heads = 1;
485 else if (!strcmp(arg, "--tags"))
486 all_tags = 1;
487 else if (!strcmp(arg, "--more"))
488 extra = 1;
489 else if (!strcmp(arg, "--list"))
490 extra = -1;
491 else if (!strcmp(arg, "--no-name"))
492 no_name = 1;
493 else if (!strcmp(arg, "--sha1-name"))
494 sha1_name = 1;
495 else if (!strncmp(arg, "--more=", 7))
496 extra = atoi(arg + 7);
497 else if (!strcmp(arg, "--merge-base"))
498 merge_base = 1;
499 else if (!strcmp(arg, "--independent"))
500 independent = 1;
501 else if (!strcmp(arg, "--topo-order"))
502 topo_order = 1;
503 else
504 usage(show_branch_usage);
505 ac--; av++;
506 }
507 ac--; av++;
508 /* Only one of these is allowed */
510 if (1 < independent + merge_base + (extra != 0))
511 usage(show_branch_usage);
512 if (all_heads + all_tags)
514 snarf_refs(all_heads, all_tags);
515 if (ac) {
517 while (0 < ac) {
518 append_one_rev(*av);
519 ac--; av++;
520 }
521 }
522 else {
523 /* If no revs given, then add heads */
524 snarf_refs(1, 0);
525 }
526 if (!ref_name_cnt) {
527 fprintf(stderr, "No revs to be shown.\n");
528 exit(0);
529 }
530 for (num_rev = 0; ref_name[num_rev]; num_rev++) {
532 unsigned char revkey[20];
533 unsigned int flag = 1u << (num_rev + REV_SHIFT);
534 if (MAX_REVS <= num_rev)
536 die("cannot handle more than %d revs.", MAX_REVS);
537 if (get_sha1(ref_name[num_rev], revkey))
538 die("'%s' is not a valid ref.\n", ref_name[num_rev]);
539 commit = lookup_commit_reference(revkey);
540 if (!commit)
541 die("cannot find commit %s (%s)",
542 ref_name[num_rev], revkey);
543 parse_commit(commit);
544 mark_seen(commit, &seen);
545 /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
547 * and so on. REV_SHIFT bits from bit 0 are used for
548 * internal bookkeeping.
549 */
550 commit->object.flags |= flag;
551 if (commit->object.flags == flag)
552 insert_by_date(commit, &list);
553 rev[num_rev] = commit;
554 }
555 for (i = 0; i < num_rev; i++)
556 rev_mask[i] = rev[i]->object.flags;
557 if (0 <= extra)
559 join_revs(&list, &seen, num_rev, extra);
560 head_path_p = resolve_ref(git_path("HEAD"), head_sha1, 1);
562 if (head_path_p) {
563 head_path_len = strlen(head_path_p);
564 memcpy(head_path, head_path_p, head_path_len + 1);
565 }
566 else {
567 head_path_len = 0;
568 head_path[0] = 0;
569 }
570 if (merge_base)
572 return show_merge_base(seen, num_rev);
573 if (independent)
575 return show_independent(rev, num_rev, ref_name, rev_mask);
576 /* Show list; --more=-1 means list-only */
578 if (1 < num_rev || extra < 0) {
579 for (i = 0; i < num_rev; i++) {
580 int j;
581 int is_head = rev_is_head(head_path,
582 head_path_len,
583 ref_name[i],
584 head_sha1,
585 rev[i]->object.sha1);
586 if (extra < 0)
587 printf("%c [%s] ",
588 is_head ? '*' : ' ', ref_name[i]);
589 else {
590 for (j = 0; j < i; j++)
591 putchar(' ');
592 printf("%c [%s] ",
593 is_head ? '*' : '!', ref_name[i]);
594 }
595 /* header lines never need name */
596 show_one_commit(rev[i], 1);
597 }
598 if (0 <= extra) {
599 for (i = 0; i < num_rev; i++)
600 putchar('-');
601 putchar('\n');
602 }
603 }
604 if (extra < 0)
605 exit(0);
606 /* Sort topologically */
608 if (topo_order)
609 sort_in_topological_order(&seen);
610 /* Give names to commits */
612 if (!sha1_name && !no_name)
613 name_commits(seen, rev, ref_name, num_rev);
614 all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
616 all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
617 while (seen) {
619 struct commit *commit = pop_one_commit(&seen);
620 int this_flag = commit->object.flags;
621 shown_merge_point |= ((this_flag & all_revs) == all_revs);
623 if (1 < num_rev) {
625 for (i = 0; i < num_rev; i++)
626 putchar((this_flag & (1u << (i + REV_SHIFT)))
627 ? '+' : ' ');
628 putchar(' ');
629 }
630 show_one_commit(commit, no_name);
631 if (shown_merge_point && --extra < 0)
633 break;
634 }
635 return 0;
636}