Merge branch 'js/builtin-add-i-cmds' into maint
[git] / builtin / name-rev.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "repository.h"
4 #include "config.h"
5 #include "commit.h"
6 #include "tag.h"
7 #include "refs.h"
8 #include "parse-options.h"
9 #include "prio-queue.h"
10 #include "sha1-lookup.h"
11 #include "commit-slab.h"
12
13 /*
14  * One day.  See the 'name a rev shortly after epoch' test in t6120 when
15  * changing this value
16  */
17 #define CUTOFF_DATE_SLOP 86400
18
19 typedef struct rev_name {
20         const char *tip_name;
21         timestamp_t taggerdate;
22         int generation;
23         int distance;
24         int from_tag;
25 } rev_name;
26
27 define_commit_slab(commit_rev_name, struct rev_name *);
28
29 static timestamp_t cutoff = TIME_MAX;
30 static struct commit_rev_name rev_names;
31
32 /* How many generations are maximally preferred over _one_ merge traversal? */
33 #define MERGE_TRAVERSAL_WEIGHT 65535
34
35 static struct rev_name *get_commit_rev_name(struct commit *commit)
36 {
37         struct rev_name **slot = commit_rev_name_peek(&rev_names, commit);
38
39         return slot ? *slot : NULL;
40 }
41
42 static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
43 {
44         *commit_rev_name_at(&rev_names, commit) = name;
45 }
46
47 static int is_better_name(struct rev_name *name,
48                           timestamp_t taggerdate,
49                           int distance,
50                           int from_tag)
51 {
52         /*
53          * When comparing names based on tags, prefer names
54          * based on the older tag, even if it is farther away.
55          */
56         if (from_tag && name->from_tag)
57                 return (name->taggerdate > taggerdate ||
58                         (name->taggerdate == taggerdate &&
59                          name->distance > distance));
60
61         /*
62          * We know that at least one of them is a non-tag at this point.
63          * favor a tag over a non-tag.
64          */
65         if (name->from_tag != from_tag)
66                 return from_tag;
67
68         /*
69          * We are now looking at two non-tags.  Tiebreak to favor
70          * shorter hops.
71          */
72         if (name->distance != distance)
73                 return name->distance > distance;
74
75         /* ... or tiebreak to favor older date */
76         if (name->taggerdate != taggerdate)
77                 return name->taggerdate > taggerdate;
78
79         /* keep the current one if we cannot decide */
80         return 0;
81 }
82
83 static struct rev_name *create_or_update_name(struct commit *commit,
84                                               const char *tip_name,
85                                               timestamp_t taggerdate,
86                                               int generation, int distance,
87                                               int from_tag)
88 {
89         struct rev_name *name = get_commit_rev_name(commit);
90
91         if (name == NULL) {
92                 name = xmalloc(sizeof(*name));
93                 set_commit_rev_name(commit, name);
94                 goto copy_data;
95         } else if (is_better_name(name, taggerdate, distance, from_tag)) {
96 copy_data:
97                 name->tip_name = tip_name;
98                 name->taggerdate = taggerdate;
99                 name->generation = generation;
100                 name->distance = distance;
101                 name->from_tag = from_tag;
102
103                 return name;
104         } else
105                 return NULL;
106 }
107
108 static void name_rev(struct commit *start_commit,
109                 const char *tip_name, timestamp_t taggerdate,
110                 int from_tag, int deref)
111 {
112         struct prio_queue queue;
113         struct commit *commit;
114         struct commit **parents_to_queue = NULL;
115         size_t parents_to_queue_nr, parents_to_queue_alloc = 0;
116         char *to_free = NULL;
117
118         parse_commit(start_commit);
119         if (start_commit->date < cutoff)
120                 return;
121
122         if (deref)
123                 tip_name = to_free = xstrfmt("%s^0", tip_name);
124
125         if (!create_or_update_name(start_commit, tip_name, taggerdate, 0, 0,
126                                    from_tag)) {
127                 free(to_free);
128                 return;
129         }
130
131         memset(&queue, 0, sizeof(queue)); /* Use the prio_queue as LIFO */
132         prio_queue_put(&queue, start_commit);
133
134         while ((commit = prio_queue_get(&queue))) {
135                 struct rev_name *name = get_commit_rev_name(commit);
136                 struct commit_list *parents;
137                 int parent_number = 1;
138
139                 parents_to_queue_nr = 0;
140
141                 for (parents = commit->parents;
142                                 parents;
143                                 parents = parents->next, parent_number++) {
144                         struct commit *parent = parents->item;
145                         const char *new_name;
146                         int generation, distance;
147
148                         parse_commit(parent);
149                         if (parent->date < cutoff)
150                                 continue;
151
152                         if (parent_number > 1) {
153                                 size_t len;
154
155                                 strip_suffix(name->tip_name, "^0", &len);
156                                 if (name->generation > 0)
157                                         new_name = xstrfmt("%.*s~%d^%d",
158                                                            (int)len,
159                                                            name->tip_name,
160                                                            name->generation,
161                                                            parent_number);
162                                 else
163                                         new_name = xstrfmt("%.*s^%d", (int)len,
164                                                            name->tip_name,
165                                                            parent_number);
166                                 generation = 0;
167                                 distance = name->distance + MERGE_TRAVERSAL_WEIGHT;
168                         } else {
169                                 new_name = name->tip_name;
170                                 generation = name->generation + 1;
171                                 distance = name->distance + 1;
172                         }
173
174                         if (create_or_update_name(parent, new_name, taggerdate,
175                                                   generation, distance,
176                                                   from_tag)) {
177                                 ALLOC_GROW(parents_to_queue,
178                                            parents_to_queue_nr + 1,
179                                            parents_to_queue_alloc);
180                                 parents_to_queue[parents_to_queue_nr] = parent;
181                                 parents_to_queue_nr++;
182                         }
183                 }
184
185                 /* The first parent must come out first from the prio_queue */
186                 while (parents_to_queue_nr)
187                         prio_queue_put(&queue,
188                                        parents_to_queue[--parents_to_queue_nr]);
189         }
190
191         clear_prio_queue(&queue);
192         free(parents_to_queue);
193 }
194
195 static int subpath_matches(const char *path, const char *filter)
196 {
197         const char *subpath = path;
198
199         while (subpath) {
200                 if (!wildmatch(filter, subpath, 0))
201                         return subpath - path;
202                 subpath = strchr(subpath, '/');
203                 if (subpath)
204                         subpath++;
205         }
206         return -1;
207 }
208
209 static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
210 {
211         if (shorten_unambiguous)
212                 refname = shorten_unambiguous_ref(refname, 0);
213         else if (skip_prefix(refname, "refs/heads/", &refname))
214                 ; /* refname already advanced */
215         else
216                 skip_prefix(refname, "refs/", &refname);
217         return refname;
218 }
219
220 struct name_ref_data {
221         int tags_only;
222         int name_only;
223         struct string_list ref_filters;
224         struct string_list exclude_filters;
225 };
226
227 static struct tip_table {
228         struct tip_table_entry {
229                 struct object_id oid;
230                 const char *refname;
231         } *table;
232         int nr;
233         int alloc;
234         int sorted;
235 } tip_table;
236
237 static void add_to_tip_table(const struct object_id *oid, const char *refname,
238                              int shorten_unambiguous)
239 {
240         refname = name_ref_abbrev(refname, shorten_unambiguous);
241
242         ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
243         oidcpy(&tip_table.table[tip_table.nr].oid, oid);
244         tip_table.table[tip_table.nr].refname = xstrdup(refname);
245         tip_table.nr++;
246         tip_table.sorted = 0;
247 }
248
249 static int tipcmp(const void *a_, const void *b_)
250 {
251         const struct tip_table_entry *a = a_, *b = b_;
252         return oidcmp(&a->oid, &b->oid);
253 }
254
255 static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
256 {
257         struct object *o = parse_object(the_repository, oid);
258         struct name_ref_data *data = cb_data;
259         int can_abbreviate_output = data->tags_only && data->name_only;
260         int deref = 0;
261         timestamp_t taggerdate = TIME_MAX;
262
263         if (data->tags_only && !starts_with(path, "refs/tags/"))
264                 return 0;
265
266         if (data->exclude_filters.nr) {
267                 struct string_list_item *item;
268
269                 for_each_string_list_item(item, &data->exclude_filters) {
270                         if (subpath_matches(path, item->string) >= 0)
271                                 return 0;
272                 }
273         }
274
275         if (data->ref_filters.nr) {
276                 struct string_list_item *item;
277                 int matched = 0;
278
279                 /* See if any of the patterns match. */
280                 for_each_string_list_item(item, &data->ref_filters) {
281                         /*
282                          * Check all patterns even after finding a match, so
283                          * that we can see if a match with a subpath exists.
284                          * When a user asked for 'refs/tags/v*' and 'v1.*',
285                          * both of which match, the user is showing her
286                          * willingness to accept a shortened output by having
287                          * the 'v1.*' in the acceptable refnames, so we
288                          * shouldn't stop when seeing 'refs/tags/v1.4' matches
289                          * 'refs/tags/v*'.  We should show it as 'v1.4'.
290                          */
291                         switch (subpath_matches(path, item->string)) {
292                         case -1: /* did not match */
293                                 break;
294                         case 0: /* matched fully */
295                                 matched = 1;
296                                 break;
297                         default: /* matched subpath */
298                                 matched = 1;
299                                 can_abbreviate_output = 1;
300                                 break;
301                         }
302                 }
303
304                 /* If none of the patterns matched, stop now */
305                 if (!matched)
306                         return 0;
307         }
308
309         add_to_tip_table(oid, path, can_abbreviate_output);
310
311         while (o && o->type == OBJ_TAG) {
312                 struct tag *t = (struct tag *) o;
313                 if (!t->tagged)
314                         break; /* broken repository */
315                 o = parse_object(the_repository, &t->tagged->oid);
316                 deref = 1;
317                 taggerdate = t->date;
318         }
319         if (o && o->type == OBJ_COMMIT) {
320                 struct commit *commit = (struct commit *)o;
321                 int from_tag = starts_with(path, "refs/tags/");
322
323                 if (taggerdate == TIME_MAX)
324                         taggerdate = commit->date;
325                 path = name_ref_abbrev(path, can_abbreviate_output);
326                 name_rev(commit, xstrdup(path), taggerdate, from_tag, deref);
327         }
328         return 0;
329 }
330
331 static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
332 {
333         struct tip_table_entry *table = table_;
334         return table[ix].oid.hash;
335 }
336
337 static const char *get_exact_ref_match(const struct object *o)
338 {
339         int found;
340
341         if (!tip_table.table || !tip_table.nr)
342                 return NULL;
343
344         if (!tip_table.sorted) {
345                 QSORT(tip_table.table, tip_table.nr, tipcmp);
346                 tip_table.sorted = 1;
347         }
348
349         found = sha1_pos(o->oid.hash, tip_table.table, tip_table.nr,
350                          nth_tip_table_ent);
351         if (0 <= found)
352                 return tip_table.table[found].refname;
353         return NULL;
354 }
355
356 /* may return a constant string or use "buf" as scratch space */
357 static const char *get_rev_name(const struct object *o, struct strbuf *buf)
358 {
359         struct rev_name *n;
360         struct commit *c;
361
362         if (o->type != OBJ_COMMIT)
363                 return get_exact_ref_match(o);
364         c = (struct commit *) o;
365         n = get_commit_rev_name(c);
366         if (!n)
367                 return NULL;
368
369         if (!n->generation)
370                 return n->tip_name;
371         else {
372                 strbuf_reset(buf);
373                 strbuf_addstr(buf, n->tip_name);
374                 strbuf_strip_suffix(buf, "^0");
375                 strbuf_addf(buf, "~%d", n->generation);
376                 return buf->buf;
377         }
378 }
379
380 static void show_name(const struct object *obj,
381                       const char *caller_name,
382                       int always, int allow_undefined, int name_only)
383 {
384         const char *name;
385         const struct object_id *oid = &obj->oid;
386         struct strbuf buf = STRBUF_INIT;
387
388         if (!name_only)
389                 printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
390         name = get_rev_name(obj, &buf);
391         if (name)
392                 printf("%s\n", name);
393         else if (allow_undefined)
394                 printf("undefined\n");
395         else if (always)
396                 printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
397         else
398                 die("cannot describe '%s'", oid_to_hex(oid));
399         strbuf_release(&buf);
400 }
401
402 static char const * const name_rev_usage[] = {
403         N_("git name-rev [<options>] <commit>..."),
404         N_("git name-rev [<options>] --all"),
405         N_("git name-rev [<options>] --stdin"),
406         NULL
407 };
408
409 static void name_rev_line(char *p, struct name_ref_data *data)
410 {
411         struct strbuf buf = STRBUF_INIT;
412         int counter = 0;
413         char *p_start;
414         const unsigned hexsz = the_hash_algo->hexsz;
415
416         for (p_start = p; *p; p++) {
417 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
418                 if (!ishex(*p))
419                         counter = 0;
420                 else if (++counter == hexsz &&
421                          !ishex(*(p+1))) {
422                         struct object_id oid;
423                         const char *name = NULL;
424                         char c = *(p+1);
425                         int p_len = p - p_start + 1;
426
427                         counter = 0;
428
429                         *(p+1) = 0;
430                         if (!get_oid(p - (hexsz - 1), &oid)) {
431                                 struct object *o =
432                                         lookup_object(the_repository, &oid);
433                                 if (o)
434                                         name = get_rev_name(o, &buf);
435                         }
436                         *(p+1) = c;
437
438                         if (!name)
439                                 continue;
440
441                         if (data->name_only)
442                                 printf("%.*s%s", p_len - hexsz, p_start, name);
443                         else
444                                 printf("%.*s (%s)", p_len, p_start, name);
445                         p_start = p + 1;
446                 }
447         }
448
449         /* flush */
450         if (p_start != p)
451                 fwrite(p_start, p - p_start, 1, stdout);
452
453         strbuf_release(&buf);
454 }
455
456 int cmd_name_rev(int argc, const char **argv, const char *prefix)
457 {
458         struct object_array revs = OBJECT_ARRAY_INIT;
459         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
460         struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
461         struct option opts[] = {
462                 OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
463                 OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
464                 OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
465                                    N_("only use refs matching <pattern>")),
466                 OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
467                                    N_("ignore refs matching <pattern>")),
468                 OPT_GROUP(""),
469                 OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
470                 OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
471                 OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
472                 OPT_BOOL(0, "always",     &always,
473                            N_("show abbreviated commit object as fallback")),
474                 {
475                         /* A Hidden OPT_BOOL */
476                         OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
477                         N_("dereference tags in the input (internal use)"),
478                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
479                 },
480                 OPT_END(),
481         };
482
483         init_commit_rev_name(&rev_names);
484         git_config(git_default_config, NULL);
485         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
486         if (all + transform_stdin + !!argc > 1) {
487                 error("Specify either a list, or --all, not both!");
488                 usage_with_options(name_rev_usage, opts);
489         }
490         if (all || transform_stdin)
491                 cutoff = 0;
492
493         for (; argc; argc--, argv++) {
494                 struct object_id oid;
495                 struct object *object;
496                 struct commit *commit;
497
498                 if (get_oid(*argv, &oid)) {
499                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
500                                         *argv);
501                         continue;
502                 }
503
504                 commit = NULL;
505                 object = parse_object(the_repository, &oid);
506                 if (object) {
507                         struct object *peeled = deref_tag(the_repository,
508                                                           object, *argv, 0);
509                         if (peeled && peeled->type == OBJ_COMMIT)
510                                 commit = (struct commit *)peeled;
511                 }
512
513                 if (!object) {
514                         fprintf(stderr, "Could not get object for %s. Skipping.\n",
515                                         *argv);
516                         continue;
517                 }
518
519                 if (commit) {
520                         if (cutoff > commit->date)
521                                 cutoff = commit->date;
522                 }
523
524                 if (peel_tag) {
525                         if (!commit) {
526                                 fprintf(stderr, "Could not get commit for %s. Skipping.\n",
527                                         *argv);
528                                 continue;
529                         }
530                         object = (struct object *)commit;
531                 }
532                 add_object_array(object, *argv, &revs);
533         }
534
535         if (cutoff) {
536                 /* check for undeflow */
537                 if (cutoff > TIME_MIN + CUTOFF_DATE_SLOP)
538                         cutoff = cutoff - CUTOFF_DATE_SLOP;
539                 else
540                         cutoff = TIME_MIN;
541         }
542         for_each_ref(name_ref, &data);
543
544         if (transform_stdin) {
545                 char buffer[2048];
546
547                 while (!feof(stdin)) {
548                         char *p = fgets(buffer, sizeof(buffer), stdin);
549                         if (!p)
550                                 break;
551                         name_rev_line(p, &data);
552                 }
553         } else if (all) {
554                 int i, max;
555
556                 max = get_max_object_index();
557                 for (i = 0; i < max; i++) {
558                         struct object *obj = get_indexed_object(i);
559                         if (!obj || obj->type != OBJ_COMMIT)
560                                 continue;
561                         show_name(obj, NULL,
562                                   always, allow_undefined, data.name_only);
563                 }
564         } else {
565                 int i;
566                 for (i = 0; i < revs.nr; i++)
567                         show_name(revs.objects[i].item, revs.objects[i].name,
568                                   always, allow_undefined, data.name_only);
569         }
570
571         UNLEAK(revs);
572         return 0;
573 }