Merge branch 'hb/hg-to-git-py3'
[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 "sha1-lookup.h"
10 #include "commit-slab.h"
11
12 #define CUTOFF_DATE_SLOP 86400 /* one day */
13
14 typedef struct rev_name {
15         const char *tip_name;
16         timestamp_t taggerdate;
17         int generation;
18         int distance;
19         int from_tag;
20 } rev_name;
21
22 define_commit_slab(commit_rev_name, struct rev_name *);
23
24 static timestamp_t cutoff = TIME_MAX;
25 static struct commit_rev_name rev_names;
26
27 /* How many generations are maximally preferred over _one_ merge traversal? */
28 #define MERGE_TRAVERSAL_WEIGHT 65535
29
30 static struct rev_name *get_commit_rev_name(struct commit *commit)
31 {
32         struct rev_name **slot = commit_rev_name_peek(&rev_names, commit);
33
34         return slot ? *slot : NULL;
35 }
36
37 static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
38 {
39         *commit_rev_name_at(&rev_names, commit) = name;
40 }
41
42 static int is_better_name(struct rev_name *name,
43                           timestamp_t taggerdate,
44                           int distance,
45                           int from_tag)
46 {
47         /*
48          * When comparing names based on tags, prefer names
49          * based on the older tag, even if it is farther away.
50          */
51         if (from_tag && name->from_tag)
52                 return (name->taggerdate > taggerdate ||
53                         (name->taggerdate == taggerdate &&
54                          name->distance > distance));
55
56         /*
57          * We know that at least one of them is a non-tag at this point.
58          * favor a tag over a non-tag.
59          */
60         if (name->from_tag != from_tag)
61                 return from_tag;
62
63         /*
64          * We are now looking at two non-tags.  Tiebreak to favor
65          * shorter hops.
66          */
67         if (name->distance != distance)
68                 return name->distance > distance;
69
70         /* ... or tiebreak to favor older date */
71         if (name->taggerdate != taggerdate)
72                 return name->taggerdate > taggerdate;
73
74         /* keep the current one if we cannot decide */
75         return 0;
76 }
77
78 static void name_rev(struct commit *commit,
79                 const char *tip_name, timestamp_t taggerdate,
80                 int generation, int distance, int from_tag,
81                 int deref)
82 {
83         struct rev_name *name = get_commit_rev_name(commit);
84         struct commit_list *parents;
85         int parent_number = 1;
86         char *to_free = NULL;
87
88         parse_commit(commit);
89
90         if (commit->date < cutoff)
91                 return;
92
93         if (deref) {
94                 tip_name = to_free = xstrfmt("%s^0", tip_name);
95
96                 if (generation)
97                         die("generation: %d, but deref?", generation);
98         }
99
100         if (name == NULL) {
101                 name = xmalloc(sizeof(rev_name));
102                 set_commit_rev_name(commit, name);
103                 goto copy_data;
104         } else if (is_better_name(name, taggerdate, distance, from_tag)) {
105 copy_data:
106                 name->tip_name = tip_name;
107                 name->taggerdate = taggerdate;
108                 name->generation = generation;
109                 name->distance = distance;
110                 name->from_tag = from_tag;
111         } else {
112                 free(to_free);
113                 return;
114         }
115
116         for (parents = commit->parents;
117                         parents;
118                         parents = parents->next, parent_number++) {
119                 if (parent_number > 1) {
120                         size_t len;
121                         char *new_name;
122
123                         strip_suffix(tip_name, "^0", &len);
124                         if (generation > 0)
125                                 new_name = xstrfmt("%.*s~%d^%d", (int)len, tip_name,
126                                                    generation, parent_number);
127                         else
128                                 new_name = xstrfmt("%.*s^%d", (int)len, tip_name,
129                                                    parent_number);
130
131                         name_rev(parents->item, new_name, taggerdate, 0,
132                                  distance + MERGE_TRAVERSAL_WEIGHT,
133                                  from_tag, 0);
134                 } else {
135                         name_rev(parents->item, tip_name, taggerdate,
136                                  generation + 1, distance + 1,
137                                  from_tag, 0);
138                 }
139         }
140 }
141
142 static int subpath_matches(const char *path, const char *filter)
143 {
144         const char *subpath = path;
145
146         while (subpath) {
147                 if (!wildmatch(filter, subpath, 0))
148                         return subpath - path;
149                 subpath = strchr(subpath, '/');
150                 if (subpath)
151                         subpath++;
152         }
153         return -1;
154 }
155
156 static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
157 {
158         if (shorten_unambiguous)
159                 refname = shorten_unambiguous_ref(refname, 0);
160         else if (starts_with(refname, "refs/heads/"))
161                 refname = refname + 11;
162         else if (starts_with(refname, "refs/"))
163                 refname = refname + 5;
164         return refname;
165 }
166
167 struct name_ref_data {
168         int tags_only;
169         int name_only;
170         struct string_list ref_filters;
171         struct string_list exclude_filters;
172 };
173
174 static struct tip_table {
175         struct tip_table_entry {
176                 struct object_id oid;
177                 const char *refname;
178         } *table;
179         int nr;
180         int alloc;
181         int sorted;
182 } tip_table;
183
184 static void add_to_tip_table(const struct object_id *oid, const char *refname,
185                              int shorten_unambiguous)
186 {
187         refname = name_ref_abbrev(refname, shorten_unambiguous);
188
189         ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
190         oidcpy(&tip_table.table[tip_table.nr].oid, oid);
191         tip_table.table[tip_table.nr].refname = xstrdup(refname);
192         tip_table.nr++;
193         tip_table.sorted = 0;
194 }
195
196 static int tipcmp(const void *a_, const void *b_)
197 {
198         const struct tip_table_entry *a = a_, *b = b_;
199         return oidcmp(&a->oid, &b->oid);
200 }
201
202 static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
203 {
204         struct object *o = parse_object(the_repository, oid);
205         struct name_ref_data *data = cb_data;
206         int can_abbreviate_output = data->tags_only && data->name_only;
207         int deref = 0;
208         timestamp_t taggerdate = TIME_MAX;
209
210         if (data->tags_only && !starts_with(path, "refs/tags/"))
211                 return 0;
212
213         if (data->exclude_filters.nr) {
214                 struct string_list_item *item;
215
216                 for_each_string_list_item(item, &data->exclude_filters) {
217                         if (subpath_matches(path, item->string) >= 0)
218                                 return 0;
219                 }
220         }
221
222         if (data->ref_filters.nr) {
223                 struct string_list_item *item;
224                 int matched = 0;
225
226                 /* See if any of the patterns match. */
227                 for_each_string_list_item(item, &data->ref_filters) {
228                         /*
229                          * Check all patterns even after finding a match, so
230                          * that we can see if a match with a subpath exists.
231                          * When a user asked for 'refs/tags/v*' and 'v1.*',
232                          * both of which match, the user is showing her
233                          * willingness to accept a shortened output by having
234                          * the 'v1.*' in the acceptable refnames, so we
235                          * shouldn't stop when seeing 'refs/tags/v1.4' matches
236                          * 'refs/tags/v*'.  We should show it as 'v1.4'.
237                          */
238                         switch (subpath_matches(path, item->string)) {
239                         case -1: /* did not match */
240                                 break;
241                         case 0: /* matched fully */
242                                 matched = 1;
243                                 break;
244                         default: /* matched subpath */
245                                 matched = 1;
246                                 can_abbreviate_output = 1;
247                                 break;
248                         }
249                 }
250
251                 /* If none of the patterns matched, stop now */
252                 if (!matched)
253                         return 0;
254         }
255
256         add_to_tip_table(oid, path, can_abbreviate_output);
257
258         while (o && o->type == OBJ_TAG) {
259                 struct tag *t = (struct tag *) o;
260                 if (!t->tagged)
261                         break; /* broken repository */
262                 o = parse_object(the_repository, &t->tagged->oid);
263                 deref = 1;
264                 taggerdate = t->date;
265         }
266         if (o && o->type == OBJ_COMMIT) {
267                 struct commit *commit = (struct commit *)o;
268                 int from_tag = starts_with(path, "refs/tags/");
269
270                 if (taggerdate == TIME_MAX)
271                         taggerdate = ((struct commit *)o)->date;
272                 path = name_ref_abbrev(path, can_abbreviate_output);
273                 name_rev(commit, xstrdup(path), taggerdate, 0, 0,
274                          from_tag, deref);
275         }
276         return 0;
277 }
278
279 static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
280 {
281         struct tip_table_entry *table = table_;
282         return table[ix].oid.hash;
283 }
284
285 static const char *get_exact_ref_match(const struct object *o)
286 {
287         int found;
288
289         if (!tip_table.table || !tip_table.nr)
290                 return NULL;
291
292         if (!tip_table.sorted) {
293                 QSORT(tip_table.table, tip_table.nr, tipcmp);
294                 tip_table.sorted = 1;
295         }
296
297         found = sha1_pos(o->oid.hash, tip_table.table, tip_table.nr,
298                          nth_tip_table_ent);
299         if (0 <= found)
300                 return tip_table.table[found].refname;
301         return NULL;
302 }
303
304 /* may return a constant string or use "buf" as scratch space */
305 static const char *get_rev_name(const struct object *o, struct strbuf *buf)
306 {
307         struct rev_name *n;
308         struct commit *c;
309
310         if (o->type != OBJ_COMMIT)
311                 return get_exact_ref_match(o);
312         c = (struct commit *) o;
313         n = get_commit_rev_name(c);
314         if (!n)
315                 return NULL;
316
317         if (!n->generation)
318                 return n->tip_name;
319         else {
320                 int len = strlen(n->tip_name);
321                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
322                         len -= 2;
323                 strbuf_reset(buf);
324                 strbuf_addf(buf, "%.*s~%d", len, n->tip_name, n->generation);
325                 return buf->buf;
326         }
327 }
328
329 static void show_name(const struct object *obj,
330                       const char *caller_name,
331                       int always, int allow_undefined, int name_only)
332 {
333         const char *name;
334         const struct object_id *oid = &obj->oid;
335         struct strbuf buf = STRBUF_INIT;
336
337         if (!name_only)
338                 printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
339         name = get_rev_name(obj, &buf);
340         if (name)
341                 printf("%s\n", name);
342         else if (allow_undefined)
343                 printf("undefined\n");
344         else if (always)
345                 printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
346         else
347                 die("cannot describe '%s'", oid_to_hex(oid));
348         strbuf_release(&buf);
349 }
350
351 static char const * const name_rev_usage[] = {
352         N_("git name-rev [<options>] <commit>..."),
353         N_("git name-rev [<options>] --all"),
354         N_("git name-rev [<options>] --stdin"),
355         NULL
356 };
357
358 static void name_rev_line(char *p, struct name_ref_data *data)
359 {
360         struct strbuf buf = STRBUF_INIT;
361         int counter = 0;
362         char *p_start;
363         const unsigned hexsz = the_hash_algo->hexsz;
364
365         for (p_start = p; *p; p++) {
366 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
367                 if (!ishex(*p))
368                         counter = 0;
369                 else if (++counter == hexsz &&
370                          !ishex(*(p+1))) {
371                         struct object_id oid;
372                         const char *name = NULL;
373                         char c = *(p+1);
374                         int p_len = p - p_start + 1;
375
376                         counter = 0;
377
378                         *(p+1) = 0;
379                         if (!get_oid(p - (hexsz - 1), &oid)) {
380                                 struct object *o =
381                                         lookup_object(the_repository, &oid);
382                                 if (o)
383                                         name = get_rev_name(o, &buf);
384                         }
385                         *(p+1) = c;
386
387                         if (!name)
388                                 continue;
389
390                         if (data->name_only)
391                                 printf("%.*s%s", p_len - hexsz, p_start, name);
392                         else
393                                 printf("%.*s (%s)", p_len, p_start, name);
394                         p_start = p + 1;
395                 }
396         }
397
398         /* flush */
399         if (p_start != p)
400                 fwrite(p_start, p - p_start, 1, stdout);
401
402         strbuf_release(&buf);
403 }
404
405 int cmd_name_rev(int argc, const char **argv, const char *prefix)
406 {
407         struct object_array revs = OBJECT_ARRAY_INIT;
408         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
409         struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
410         struct option opts[] = {
411                 OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
412                 OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
413                 OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
414                                    N_("only use refs matching <pattern>")),
415                 OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
416                                    N_("ignore refs matching <pattern>")),
417                 OPT_GROUP(""),
418                 OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
419                 OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
420                 OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
421                 OPT_BOOL(0, "always",     &always,
422                            N_("show abbreviated commit object as fallback")),
423                 {
424                         /* A Hidden OPT_BOOL */
425                         OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
426                         N_("dereference tags in the input (internal use)"),
427                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
428                 },
429                 OPT_END(),
430         };
431
432         init_commit_rev_name(&rev_names);
433         git_config(git_default_config, NULL);
434         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
435         if (all + transform_stdin + !!argc > 1) {
436                 error("Specify either a list, or --all, not both!");
437                 usage_with_options(name_rev_usage, opts);
438         }
439         if (all || transform_stdin)
440                 cutoff = 0;
441
442         for (; argc; argc--, argv++) {
443                 struct object_id oid;
444                 struct object *object;
445                 struct commit *commit;
446
447                 if (get_oid(*argv, &oid)) {
448                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
449                                         *argv);
450                         continue;
451                 }
452
453                 commit = NULL;
454                 object = parse_object(the_repository, &oid);
455                 if (object) {
456                         struct object *peeled = deref_tag(the_repository,
457                                                           object, *argv, 0);
458                         if (peeled && peeled->type == OBJ_COMMIT)
459                                 commit = (struct commit *)peeled;
460                 }
461
462                 if (!object) {
463                         fprintf(stderr, "Could not get object for %s. Skipping.\n",
464                                         *argv);
465                         continue;
466                 }
467
468                 if (commit) {
469                         if (cutoff > commit->date)
470                                 cutoff = commit->date;
471                 }
472
473                 if (peel_tag) {
474                         if (!commit) {
475                                 fprintf(stderr, "Could not get commit for %s. Skipping.\n",
476                                         *argv);
477                                 continue;
478                         }
479                         object = (struct object *)commit;
480                 }
481                 add_object_array(object, *argv, &revs);
482         }
483
484         if (cutoff)
485                 cutoff = cutoff - CUTOFF_DATE_SLOP;
486         for_each_ref(name_ref, &data);
487
488         if (transform_stdin) {
489                 char buffer[2048];
490
491                 while (!feof(stdin)) {
492                         char *p = fgets(buffer, sizeof(buffer), stdin);
493                         if (!p)
494                                 break;
495                         name_rev_line(p, &data);
496                 }
497         } else if (all) {
498                 int i, max;
499
500                 max = get_max_object_index();
501                 for (i = 0; i < max; i++) {
502                         struct object *obj = get_indexed_object(i);
503                         if (!obj || obj->type != OBJ_COMMIT)
504                                 continue;
505                         show_name(obj, NULL,
506                                   always, allow_undefined, data.name_only);
507                 }
508         } else {
509                 int i;
510                 for (i = 0; i < revs.nr; i++)
511                         show_name(revs.objects[i].item, revs.objects[i].name,
512                                   always, allow_undefined, data.name_only);
513         }
514
515         UNLEAK(revs);
516         return 0;
517 }