builtin/describe.c

   1 #define USE_THE_INDEX_COMPATIBILITY_MACROS
   2 #include "cache.h"
   3 #include "config.h"
   4 #include "lockfile.h"
   5 #include "commit.h"
   6 #include "tag.h"
   7 #include "blob.h"
   8 #include "refs.h"
   9 #include "builtin.h"
  10 #include "exec-cmd.h"
  11 #include "parse-options.h"
  12 #include "revision.h"
  13 #include "diff.h"
  14 #include "hashmap.h"
  15 #include "argv-array.h"
  16 #include "run-command.h"
  17 #include "object-store.h"
  18 #include "revision.h"
  19 #include "list-objects.h"
  20 #include "commit-slab.h"
  21
  22 #define MAX_TAGS        (FLAG_BITS - 1)
  23
  24 define_commit_slab(commit_names, struct commit_name *);
  25
  26 static const char * const describe_usage[] = {
  27         N_("git describe [<options>] [<commit-ish>...]"),
  28         N_("git describe [<options>] --dirty"),
  29         NULL
  30 };
  31
  32 static int debug;       /* Display lots of verbose info */
  33 static int all; /* Any valid ref can be used */
  34 static int tags;        /* Allow lightweight tags */
  35 static int longformat;
  36 static int first_parent;
  37 static int abbrev = -1; /* unspecified */
  38 static int max_candidates = 10;
  39 static struct hashmap names;
  40 static int have_util;
  41 static struct string_list patterns = STRING_LIST_INIT_NODUP;
  42 static struct string_list exclude_patterns = STRING_LIST_INIT_NODUP;
  43 static int always;
  44 static const char *suffix, *dirty, *broken;
  45 static struct commit_names commit_names;
  46
  47 /* diff-index command arguments to check if working tree is dirty. */
  48 static const char *diff_index_args[] = {
  49         "diff-index", "--quiet", "HEAD", "--", NULL
  50 };
  51
  52 struct commit_name {
  53         struct hashmap_entry entry;
  54         struct object_id peeled;
  55         struct tag *tag;
  56         unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
  57         unsigned name_checked:1;
  58         struct object_id oid;
  59         char *path;
  60 };
  61
  62 static const char *prio_names[] = {
  63         N_("head"), N_("lightweight"), N_("annotated"),
  64 };
  65
  66 static int commit_name_neq(const void *unused_cmp_data,
  67                            const struct hashmap_entry *eptr,
  68                            const struct hashmap_entry *entry_or_key,
  69                            const void *peeled)
  70 {
  71         const struct commit_name *cn1, *cn2;
  72
  73         cn1 = container_of(eptr, const struct commit_name, entry);
  74         cn2 = container_of(entry_or_key, const struct commit_name, entry);
  75
  76         return !oideq(&cn1->peeled, peeled ? peeled : &cn2->peeled);
  77 }
  78
  79 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
  80 {
  81         return hashmap_get_entry_from_hash(&names, oidhash(peeled), peeled,
  82                                                 struct commit_name, entry);
  83 }
  84
  85 static int replace_name(struct commit_name *e,
  86                                int prio,
  87                                const struct object_id *oid,
  88                                struct tag **tag)
  89 {
  90         if (!e || e->prio < prio)
  91                 return 1;
  92
  93         if (e->prio == 2 && prio == 2) {
  94                 /* Multiple annotated tags point to the same commit.
  95                  * Select one to keep based upon their tagger date.
  96                  */
  97                 struct tag *t;
  98
  99                 if (!e->tag) {
 100                         t = lookup_tag(the_repository, &e->oid);
 101                         if (!t || parse_tag(t))
 102                                 return 1;
 103                         e->tag = t;
 104                 }
 105
 106                 t = lookup_tag(the_repository, oid);
 107                 if (!t || parse_tag(t))
 108                         return 0;
 109                 *tag = t;
 110
 111                 if (e->tag->date < t->date)
 112                         return 1;
 113         }
 114
 115         return 0;
 116 }
 117
 118 static void add_to_known_names(const char *path,
 119                                const struct object_id *peeled,
 120                                int prio,
 121                                const struct object_id *oid)
 122 {
 123         struct commit_name *e = find_commit_name(peeled);
 124         struct tag *tag = NULL;
 125         if (replace_name(e, prio, oid, &tag)) {
 126                 if (!e) {
 127                         e = xmalloc(sizeof(struct commit_name));
 128                         oidcpy(&e->peeled, peeled);
 129                         hashmap_entry_init(&e->entry, oidhash(peeled));
 130                         hashmap_add(&names, &e->entry);
 131                         e->path = NULL;
 132                 }
 133                 e->tag = tag;
 134                 e->prio = prio;
 135                 e->name_checked = 0;
 136                 oidcpy(&e->oid, oid);
 137                 free(e->path);
 138                 e->path = xstrdup(path);
 139         }
 140 }
 141
 142 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
 143 {
 144         int is_tag = 0;
 145         struct object_id peeled;
 146         int is_annotated, prio;
 147         const char *path_to_match = NULL;
 148
 149         if (skip_prefix(path, "refs/tags/", &path_to_match)) {
 150                 is_tag = 1;
 151         } else if (all) {
 152                 if ((exclude_patterns.nr || patterns.nr) &&
 153                     !skip_prefix(path, "refs/heads/", &path_to_match) &&
 154                     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
 155                         /* Only accept reference of known type if there are match/exclude patterns */
 156                         return 0;
 157                 }
 158         } else {
 159                 /* Reject anything outside refs/tags/ unless --all */
 160                 return 0;
 161         }
 162
 163         /*
 164          * If we're given exclude patterns, first exclude any tag which match
 165          * any of the exclude pattern.
 166          */
 167         if (exclude_patterns.nr) {
 168                 struct string_list_item *item;
 169
 170                 for_each_string_list_item(item, &exclude_patterns) {
 171                         if (!wildmatch(item->string, path_to_match, 0))
 172                                 return 0;
 173                 }
 174         }
 175
 176         /*
 177          * If we're given patterns, accept only tags which match at least one
 178          * pattern.
 179          */
 180         if (patterns.nr) {
 181                 int found = 0;
 182                 struct string_list_item *item;
 183
 184                 for_each_string_list_item(item, &patterns) {
 185                         if (!wildmatch(item->string, path_to_match, 0)) {
 186                                 found = 1;
 187                                 break;
 188                         }
 189                 }
 190
 191                 if (!found)
 192                         return 0;
 193         }
 194
 195         /* Is it annotated? */
 196         if (!peel_ref(path, &peeled)) {
 197                 is_annotated = !oideq(oid, &peeled);
 198         } else {
 199                 oidcpy(&peeled, oid);
 200                 is_annotated = 0;
 201         }
 202
 203         /*
 204          * By default, we only use annotated tags, but with --tags
 205          * we fall back to lightweight ones (even without --tags,
 206          * we still remember lightweight ones, only to give hints
 207          * in an error message).  --all allows any refs to be used.
 208          */
 209         if (is_annotated)
 210                 prio = 2;
 211         else if (is_tag)
 212                 prio = 1;
 213         else
 214                 prio = 0;
 215
 216         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
 217         return 0;
 218 }
 219
 220 struct possible_tag {
 221         struct commit_name *name;
 222         int depth;
 223         int found_order;
 224         unsigned flag_within;
 225 };
 226
 227 static int compare_pt(const void *a_, const void *b_)
 228 {
 229         struct possible_tag *a = (struct possible_tag *)a_;
 230         struct possible_tag *b = (struct possible_tag *)b_;
 231         if (a->depth != b->depth)
 232                 return a->depth - b->depth;
 233         if (a->found_order != b->found_order)
 234                 return a->found_order - b->found_order;
 235         return 0;
 236 }
 237
 238 static unsigned long finish_depth_computation(
 239         struct commit_list **list,
 240         struct possible_tag *best)
 241 {
 242         unsigned long seen_commits = 0;
 243         while (*list) {
 244                 struct commit *c = pop_commit(list);
 245                 struct commit_list *parents = c->parents;
 246                 seen_commits++;
 247                 if (c->object.flags & best->flag_within) {
 248                         struct commit_list *a = *list;
 249                         while (a) {
 250                                 struct commit *i = a->item;
 251                                 if (!(i->object.flags & best->flag_within))
 252                                         break;
 253                                 a = a->next;
 254                         }
 255                         if (!a)
 256                                 break;
 257                 } else
 258                         best->depth++;
 259                 while (parents) {
 260                         struct commit *p = parents->item;
 261                         parse_commit(p);
 262                         if (!(p->object.flags & SEEN))
 263                                 commit_list_insert_by_date(p, list);
 264                         p->object.flags |= c->object.flags;
 265                         parents = parents->next;
 266                 }
 267         }
 268         return seen_commits;
 269 }
 270
 271 static void append_name(struct commit_name *n, struct strbuf *dst)
 272 {
 273         if (n->prio == 2 && !n->tag) {
 274                 n->tag = lookup_tag(the_repository, &n->oid);
 275                 if (!n->tag || parse_tag(n->tag))
 276                         die(_("annotated tag %s not available"), n->path);
 277         }
 278         if (n->tag && !n->name_checked) {
 279                 if (!n->tag->tag)
 280                         die(_("annotated tag %s has no embedded name"), n->path);
 281                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
 282                         warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
 283                 n->name_checked = 1;
 284         }
 285
 286         if (n->tag) {
 287                 if (all)
 288                         strbuf_addstr(dst, "tags/");
 289                 strbuf_addstr(dst, n->tag->tag);
 290         } else {
 291                 strbuf_addstr(dst, n->path);
 292         }
 293 }
 294
 295 static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
 296 {
 297         strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid, abbrev));
 298 }
 299
 300 static void describe_commit(struct object_id *oid, struct strbuf *dst)
 301 {
 302         struct commit *cmit, *gave_up_on = NULL;
 303         struct commit_list *list;
 304         struct commit_name *n;
 305         struct possible_tag all_matches[MAX_TAGS];
 306         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
 307         unsigned long seen_commits = 0;
 308         unsigned int unannotated_cnt = 0;
 309
 310         cmit = lookup_commit_reference(the_repository, oid);
 311
 312         n = find_commit_name(&cmit->object.oid);
 313         if (n && (tags || all || n->prio == 2)) {
 314                 /*
 315                  * Exact match to an existing ref.
 316                  */
 317                 append_name(n, dst);
 318                 if (longformat)
 319                         append_suffix(0, n->tag ? &n->tag->tagged->oid : oid, dst);
 320                 if (suffix)
 321                         strbuf_addstr(dst, suffix);
 322                 return;
 323         }
 324
 325         if (!max_candidates)
 326                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
 327         if (debug)
 328                 fprintf(stderr, _("No exact match on refs or tags, searching to describe\n"));
 329
 330         if (!have_util) {
 331                 struct hashmap_iter iter;
 332                 struct commit *c;
 333                 struct commit_name *n;
 334
 335                 init_commit_names(&commit_names);
 336                 n = hashmap_iter_first(&names, &iter);
 337                 for (; n; n = hashmap_iter_next(&iter)) {
 338                         c = lookup_commit_reference_gently(the_repository,
 339                                                            &n->peeled, 1);
 340                         if (c)
 341                                 *commit_names_at(&commit_names, c) = n;
 342                 }
 343                 have_util = 1;
 344         }
 345
 346         list = NULL;
 347         cmit->object.flags = SEEN;
 348         commit_list_insert(cmit, &list);
 349         while (list) {
 350                 struct commit *c = pop_commit(&list);
 351                 struct commit_list *parents = c->parents;
 352                 struct commit_name **slot;
 353
 354                 seen_commits++;
 355                 slot = commit_names_peek(&commit_names, c);
 356                 n = slot ? *slot : NULL;
 357                 if (n) {
 358                         if (!tags && !all && n->prio < 2) {
 359                                 unannotated_cnt++;
 360                         } else if (match_cnt < max_candidates) {
 361                                 struct possible_tag *t = &all_matches[match_cnt++];
 362                                 t->name = n;
 363                                 t->depth = seen_commits - 1;
 364                                 t->flag_within = 1u << match_cnt;
 365                                 t->found_order = match_cnt;
 366                                 c->object.flags |= t->flag_within;
 367                                 if (n->prio == 2)
 368                                         annotated_cnt++;
 369                         }
 370                         else {
 371                                 gave_up_on = c;
 372                                 break;
 373                         }
 374                 }
 375                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 376                         struct possible_tag *t = &all_matches[cur_match];
 377                         if (!(c->object.flags & t->flag_within))
 378                                 t->depth++;
 379                 }
 380                 if (annotated_cnt && !list) {
 381                         if (debug)
 382                                 fprintf(stderr, _("finished search at %s\n"),
 383                                         oid_to_hex(&c->object.oid));
 384                         break;
 385                 }
 386                 while (parents) {
 387                         struct commit *p = parents->item;
 388                         parse_commit(p);
 389                         if (!(p->object.flags & SEEN))
 390                                 commit_list_insert_by_date(p, &list);
 391                         p->object.flags |= c->object.flags;
 392                         parents = parents->next;
 393
 394                         if (first_parent)
 395                                 break;
 396                 }
 397         }
 398
 399         if (!match_cnt) {
 400                 struct object_id *cmit_oid = &cmit->object.oid;
 401                 if (always) {
 402                         strbuf_add_unique_abbrev(dst, cmit_oid, abbrev);
 403                         if (suffix)
 404                                 strbuf_addstr(dst, suffix);
 405                         return;
 406                 }
 407                 if (unannotated_cnt)
 408                         die(_("No annotated tags can describe '%s'.\n"
 409                             "However, there were unannotated tags: try --tags."),
 410                             oid_to_hex(cmit_oid));
 411                 else
 412                         die(_("No tags can describe '%s'.\n"
 413                             "Try --always, or create some tags."),
 414                             oid_to_hex(cmit_oid));
 415         }
 416
 417         QSORT(all_matches, match_cnt, compare_pt);
 418
 419         if (gave_up_on) {
 420                 commit_list_insert_by_date(gave_up_on, &list);
 421                 seen_commits--;
 422         }
 423         seen_commits += finish_depth_computation(&list, &all_matches[0]);
 424         free_commit_list(list);
 425
 426         if (debug) {
 427                 static int label_width = -1;
 428                 if (label_width < 0) {
 429                         int i, w;
 430                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
 431                                 w = strlen(_(prio_names[i]));
 432                                 if (label_width < w)
 433                                         label_width = w;
 434                         }
 435                 }
 436                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 437                         struct possible_tag *t = &all_matches[cur_match];
 438                         fprintf(stderr, " %-*s %8d %s\n",
 439                                 label_width, _(prio_names[t->name->prio]),
 440                                 t->depth, t->name->path);
 441                 }
 442                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
 443                 if (gave_up_on) {
 444                         fprintf(stderr,
 445                                 _("more than %i tags found; listed %i most recent\n"
 446                                 "gave up search at %s\n"),
 447                                 max_candidates, max_candidates,
 448                                 oid_to_hex(&gave_up_on->object.oid));
 449                 }
 450         }
 451
 452         append_name(all_matches[0].name, dst);
 453         if (abbrev)
 454                 append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
 455         if (suffix)
 456                 strbuf_addstr(dst, suffix);
 457 }
 458
 459 struct process_commit_data {
 460         struct object_id current_commit;
 461         struct object_id looking_for;
 462         struct strbuf *dst;
 463         struct rev_info *revs;
 464 };
 465
 466 static void process_commit(struct commit *commit, void *data)
 467 {
 468         struct process_commit_data *pcd = data;
 469         pcd->current_commit = commit->object.oid;
 470 }
 471
 472 static void process_object(struct object *obj, const char *path, void *data)
 473 {
 474         struct process_commit_data *pcd = data;
 475
 476         if (oideq(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
 477                 reset_revision_walk();
 478                 describe_commit(&pcd->current_commit, pcd->dst);
 479                 strbuf_addf(pcd->dst, ":%s", path);
 480                 free_commit_list(pcd->revs->commits);
 481                 pcd->revs->commits = NULL;
 482         }
 483 }
 484
 485 static void describe_blob(struct object_id oid, struct strbuf *dst)
 486 {
 487         struct rev_info revs;
 488         struct argv_array args = ARGV_ARRAY_INIT;
 489         struct process_commit_data pcd = { null_oid, oid, dst, &revs};
 490
 491         argv_array_pushl(&args, "internal: The first arg is not parsed",
 492                 "--objects", "--in-commit-order", "--reverse", "HEAD",
 493                 NULL);
 494
 495         repo_init_revisions(the_repository, &revs, NULL);
 496         if (setup_revisions(args.argc, args.argv, &revs, NULL) > 1)
 497                 BUG("setup_revisions could not handle all args?");
 498
 499         if (prepare_revision_walk(&revs))
 500                 die("revision walk setup failed");
 501
 502         traverse_commit_list(&revs, process_commit, process_object, &pcd);
 503         reset_revision_walk();
 504 }
 505
 506 static void describe(const char *arg, int last_one)
 507 {
 508         struct object_id oid;
 509         struct commit *cmit;
 510         struct strbuf sb = STRBUF_INIT;
 511
 512         if (debug)
 513                 fprintf(stderr, _("describe %s\n"), arg);
 514
 515         if (get_oid(arg, &oid))
 516                 die(_("Not a valid object name %s"), arg);
 517         cmit = lookup_commit_reference_gently(the_repository, &oid, 1);
 518
 519         if (cmit)
 520                 describe_commit(&oid, &sb);
 521         else if (oid_object_info(the_repository, &oid, NULL) == OBJ_BLOB)
 522                 describe_blob(oid, &sb);
 523         else
 524                 die(_("%s is neither a commit nor blob"), arg);
 525
 526         puts(sb.buf);
 527
 528         if (!last_one)
 529                 clear_commit_marks(cmit, -1);
 530
 531         strbuf_release(&sb);
 532 }
 533
 534 int cmd_describe(int argc, const char **argv, const char *prefix)
 535 {
 536         int contains = 0;
 537         struct option options[] = {
 538                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
 539                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
 540                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
 541                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
 542                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
 543                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
 544                 OPT__ABBREV(&abbrev),
 545                 OPT_SET_INT(0, "exact-match", &max_candidates,
 546                             N_("only output exact matches"), 0),
 547                 OPT_INTEGER(0, "candidates", &max_candidates,
 548                             N_("consider <n> most recent tags (default: 10)")),
 549                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
 550                            N_("only consider tags matching <pattern>")),
 551                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
 552                            N_("do not consider tags matching <pattern>")),
 553                 OPT_BOOL(0, "always",        &always,
 554                         N_("show abbreviated commit object as fallback")),
 555                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
 556                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
 557                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
 558                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
 559                         N_("append <mark> on broken working tree (default: \"-broken\")"),
 560                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
 561                 OPT_END(),
 562         };
 563
 564         git_config(git_default_config, NULL);
 565         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
 566         if (abbrev < 0)
 567                 abbrev = DEFAULT_ABBREV;
 568
 569         if (max_candidates < 0)
 570                 max_candidates = 0;
 571         else if (max_candidates > MAX_TAGS)
 572                 max_candidates = MAX_TAGS;
 573
 574         save_commit_buffer = 0;
 575
 576         if (longformat && abbrev == 0)
 577                 die(_("--long is incompatible with --abbrev=0"));
 578
 579         if (contains) {
 580                 struct string_list_item *item;
 581                 struct argv_array args;
 582
 583                 argv_array_init(&args);
 584                 argv_array_pushl(&args, "name-rev",
 585                                  "--peel-tag", "--name-only", "--no-undefined",
 586                                  NULL);
 587                 if (always)
 588                         argv_array_push(&args, "--always");
 589                 if (!all) {
 590                         argv_array_push(&args, "--tags");
 591                         for_each_string_list_item(item, &patterns)
 592                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
 593                         for_each_string_list_item(item, &exclude_patterns)
 594                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
 595                 }
 596                 if (argc)
 597                         argv_array_pushv(&args, argv);
 598                 else
 599                         argv_array_push(&args, "HEAD");
 600                 return cmd_name_rev(args.argc, args.argv, prefix);
 601         }
 602
 603         hashmap_init(&names, commit_name_neq, NULL, 0);
 604         for_each_rawref(get_name, NULL);
 605         if (!hashmap_get_size(&names) && !always)
 606                 die(_("No names found, cannot describe anything."));
 607
 608         if (argc == 0) {
 609                 if (broken) {
 610                         struct child_process cp = CHILD_PROCESS_INIT;
 611                         argv_array_pushv(&cp.args, diff_index_args);
 612                         cp.git_cmd = 1;
 613                         cp.no_stdin = 1;
 614                         cp.no_stdout = 1;
 615
 616                         if (!dirty)
 617                                 dirty = "-dirty";
 618
 619                         switch (run_command(&cp)) {
 620                         case 0:
 621                                 suffix = NULL;
 622                                 break;
 623                         case 1:
 624                                 suffix = dirty;
 625                                 break;
 626                         default:
 627                                 /* diff-index aborted abnormally */
 628                                 suffix = broken;
 629                         }
 630                 } else if (dirty) {
 631                         struct lock_file index_lock = LOCK_INIT;
 632                         struct rev_info revs;
 633                         struct argv_array args = ARGV_ARRAY_INIT;
 634                         int fd, result;
 635
 636                         setup_work_tree();
 637                         read_cache();
 638                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
 639                                       NULL, NULL, NULL);
 640                         fd = hold_locked_index(&index_lock, 0);
 641                         if (0 <= fd)
 642                                 repo_update_index_if_able(the_repository, &index_lock);
 643
 644                         repo_init_revisions(the_repository, &revs, prefix);
 645                         argv_array_pushv(&args, diff_index_args);
 646                         if (setup_revisions(args.argc, args.argv, &revs, NULL) != 1)
 647                                 BUG("malformed internal diff-index command line");
 648                         result = run_diff_index(&revs, 0);
 649
 650                         if (!diff_result_code(&revs.diffopt, result))
 651                                 suffix = NULL;
 652                         else
 653                                 suffix = dirty;
 654                 }
 655                 describe("HEAD", 1);
 656         } else if (dirty) {
 657                 die(_("--dirty is incompatible with commit-ishes"));
 658         } else if (broken) {
 659                 die(_("--broken is incompatible with commit-ishes"));
 660         } else {
 661                 while (argc-- > 0)
 662                         describe(*argv++, argc == 0);
 663         }
 664         return 0;
 665 }