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 void *entry,
  68                            const void *entry_or_key,
  69                            const void *peeled)
  70 {
  71         const struct commit_name *cn1 = entry;
  72         const struct commit_name *cn2 = entry_or_key;
  73
  74         return !oideq(&cn1->peeled, peeled ? peeled : &cn2->peeled);
  75 }
  76
  77 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
  78 {
  79         return hashmap_get_from_hash(&names, sha1hash(peeled->hash), peeled->hash);
  80 }
  81
  82 static int replace_name(struct commit_name *e,
  83                                int prio,
  84                                const struct object_id *oid,
  85                                struct tag **tag)
  86 {
  87         if (!e || e->prio < prio)
  88                 return 1;
  89
  90         if (e->prio == 2 && prio == 2) {
  91                 /* Multiple annotated tags point to the same commit.
  92                  * Select one to keep based upon their tagger date.
  93                  */
  94                 struct tag *t;
  95
  96                 if (!e->tag) {
  97                         t = lookup_tag(the_repository, &e->oid);
  98                         if (!t || parse_tag(t))
  99                                 return 1;
 100                         e->tag = t;
 101                 }
 102
 103                 t = lookup_tag(the_repository, oid);
 104                 if (!t || parse_tag(t))
 105                         return 0;
 106                 *tag = t;
 107
 108                 if (e->tag->date < t->date)
 109                         return 1;
 110         }
 111
 112         return 0;
 113 }
 114
 115 static void add_to_known_names(const char *path,
 116                                const struct object_id *peeled,
 117                                int prio,
 118                                const struct object_id *oid)
 119 {
 120         struct commit_name *e = find_commit_name(peeled);
 121         struct tag *tag = NULL;
 122         if (replace_name(e, prio, oid, &tag)) {
 123                 if (!e) {
 124                         e = xmalloc(sizeof(struct commit_name));
 125                         oidcpy(&e->peeled, peeled);
 126                         hashmap_entry_init(e, sha1hash(peeled->hash));
 127                         hashmap_add(&names, e);
 128                         e->path = NULL;
 129                 }
 130                 e->tag = tag;
 131                 e->prio = prio;
 132                 e->name_checked = 0;
 133                 oidcpy(&e->oid, oid);
 134                 free(e->path);
 135                 e->path = xstrdup(path);
 136         }
 137 }
 138
 139 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
 140 {
 141         int is_tag = 0;
 142         struct object_id peeled;
 143         int is_annotated, prio;
 144         const char *path_to_match = NULL;
 145
 146         if (skip_prefix(path, "refs/tags/", &path_to_match)) {
 147                 is_tag = 1;
 148         } else if (all) {
 149                 if ((exclude_patterns.nr || patterns.nr) &&
 150                     !skip_prefix(path, "refs/heads/", &path_to_match) &&
 151                     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
 152                         /* Only accept reference of known type if there are match/exclude patterns */
 153                         return 0;
 154                 }
 155         } else {
 156                 /* Reject anything outside refs/tags/ unless --all */
 157                 return 0;
 158         }
 159
 160         /*
 161          * If we're given exclude patterns, first exclude any tag which match
 162          * any of the exclude pattern.
 163          */
 164         if (exclude_patterns.nr) {
 165                 struct string_list_item *item;
 166
 167                 for_each_string_list_item(item, &exclude_patterns) {
 168                         if (!wildmatch(item->string, path_to_match, 0))
 169                                 return 0;
 170                 }
 171         }
 172
 173         /*
 174          * If we're given patterns, accept only tags which match at least one
 175          * pattern.
 176          */
 177         if (patterns.nr) {
 178                 int found = 0;
 179                 struct string_list_item *item;
 180
 181                 for_each_string_list_item(item, &patterns) {
 182                         if (!wildmatch(item->string, path_to_match, 0)) {
 183                                 found = 1;
 184                                 break;
 185                         }
 186                 }
 187
 188                 if (!found)
 189                         return 0;
 190         }
 191
 192         /* Is it annotated? */
 193         if (!peel_ref(path, &peeled)) {
 194                 is_annotated = !oideq(oid, &peeled);
 195         } else {
 196                 oidcpy(&peeled, oid);
 197                 is_annotated = 0;
 198         }
 199
 200         /*
 201          * By default, we only use annotated tags, but with --tags
 202          * we fall back to lightweight ones (even without --tags,
 203          * we still remember lightweight ones, only to give hints
 204          * in an error message).  --all allows any refs to be used.
 205          */
 206         if (is_annotated)
 207                 prio = 2;
 208         else if (is_tag)
 209                 prio = 1;
 210         else
 211                 prio = 0;
 212
 213         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
 214         return 0;
 215 }
 216
 217 struct possible_tag {
 218         struct commit_name *name;
 219         int depth;
 220         int found_order;
 221         unsigned flag_within;
 222 };
 223
 224 static int compare_pt(const void *a_, const void *b_)
 225 {
 226         struct possible_tag *a = (struct possible_tag *)a_;
 227         struct possible_tag *b = (struct possible_tag *)b_;
 228         if (a->depth != b->depth)
 229                 return a->depth - b->depth;
 230         if (a->found_order != b->found_order)
 231                 return a->found_order - b->found_order;
 232         return 0;
 233 }
 234
 235 static unsigned long finish_depth_computation(
 236         struct commit_list **list,
 237         struct possible_tag *best)
 238 {
 239         unsigned long seen_commits = 0;
 240         while (*list) {
 241                 struct commit *c = pop_commit(list);
 242                 struct commit_list *parents = c->parents;
 243                 seen_commits++;
 244                 if (c->object.flags & best->flag_within) {
 245                         struct commit_list *a = *list;
 246                         while (a) {
 247                                 struct commit *i = a->item;
 248                                 if (!(i->object.flags & best->flag_within))
 249                                         break;
 250                                 a = a->next;
 251                         }
 252                         if (!a)
 253                                 break;
 254                 } else
 255                         best->depth++;
 256                 while (parents) {
 257                         struct commit *p = parents->item;
 258                         parse_commit(p);
 259                         if (!(p->object.flags & SEEN))
 260                                 commit_list_insert_by_date(p, list);
 261                         p->object.flags |= c->object.flags;
 262                         parents = parents->next;
 263                 }
 264         }
 265         return seen_commits;
 266 }
 267
 268 static void append_name(struct commit_name *n, struct strbuf *dst)
 269 {
 270         if (n->prio == 2 && !n->tag) {
 271                 n->tag = lookup_tag(the_repository, &n->oid);
 272                 if (!n->tag || parse_tag(n->tag))
 273                         die(_("annotated tag %s not available"), n->path);
 274         }
 275         if (n->tag && !n->name_checked) {
 276                 if (!n->tag->tag)
 277                         die(_("annotated tag %s has no embedded name"), n->path);
 278                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
 279                         warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
 280                 n->name_checked = 1;
 281         }
 282
 283         if (n->tag) {
 284                 if (all)
 285                         strbuf_addstr(dst, "tags/");
 286                 strbuf_addstr(dst, n->tag->tag);
 287         } else {
 288                 strbuf_addstr(dst, n->path);
 289         }
 290 }
 291
 292 static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
 293 {
 294         strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid, abbrev));
 295 }
 296
 297 static void describe_commit(struct object_id *oid, struct strbuf *dst)
 298 {
 299         struct commit *cmit, *gave_up_on = NULL;
 300         struct commit_list *list;
 301         struct commit_name *n;
 302         struct possible_tag all_matches[MAX_TAGS];
 303         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
 304         unsigned long seen_commits = 0;
 305         unsigned int unannotated_cnt = 0;
 306
 307         cmit = lookup_commit_reference(the_repository, oid);
 308
 309         n = find_commit_name(&cmit->object.oid);
 310         if (n && (tags || all || n->prio == 2)) {
 311                 /*
 312                  * Exact match to an existing ref.
 313                  */
 314                 append_name(n, dst);
 315                 if (longformat)
 316                         append_suffix(0, n->tag ? &n->tag->tagged->oid : oid, dst);
 317                 if (suffix)
 318                         strbuf_addstr(dst, suffix);
 319                 return;
 320         }
 321
 322         if (!max_candidates)
 323                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
 324         if (debug)
 325                 fprintf(stderr, _("No exact match on refs or tags, searching to describe\n"));
 326
 327         if (!have_util) {
 328                 struct hashmap_iter iter;
 329                 struct commit *c;
 330                 struct commit_name *n;
 331
 332                 init_commit_names(&commit_names);
 333                 n = hashmap_iter_first(&names, &iter);
 334                 for (; n; n = hashmap_iter_next(&iter)) {
 335                         c = lookup_commit_reference_gently(the_repository,
 336                                                            &n->peeled, 1);
 337                         if (c)
 338                                 *commit_names_at(&commit_names, c) = n;
 339                 }
 340                 have_util = 1;
 341         }
 342
 343         list = NULL;
 344         cmit->object.flags = SEEN;
 345         commit_list_insert(cmit, &list);
 346         while (list) {
 347                 struct commit *c = pop_commit(&list);
 348                 struct commit_list *parents = c->parents;
 349                 struct commit_name **slot;
 350
 351                 seen_commits++;
 352                 slot = commit_names_peek(&commit_names, c);
 353                 n = slot ? *slot : NULL;
 354                 if (n) {
 355                         if (!tags && !all && n->prio < 2) {
 356                                 unannotated_cnt++;
 357                         } else if (match_cnt < max_candidates) {
 358                                 struct possible_tag *t = &all_matches[match_cnt++];
 359                                 t->name = n;
 360                                 t->depth = seen_commits - 1;
 361                                 t->flag_within = 1u << match_cnt;
 362                                 t->found_order = match_cnt;
 363                                 c->object.flags |= t->flag_within;
 364                                 if (n->prio == 2)
 365                                         annotated_cnt++;
 366                         }
 367                         else {
 368                                 gave_up_on = c;
 369                                 break;
 370                         }
 371                 }
 372                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 373                         struct possible_tag *t = &all_matches[cur_match];
 374                         if (!(c->object.flags & t->flag_within))
 375                                 t->depth++;
 376                 }
 377                 if (annotated_cnt && !list) {
 378                         if (debug)
 379                                 fprintf(stderr, _("finished search at %s\n"),
 380                                         oid_to_hex(&c->object.oid));
 381                         break;
 382                 }
 383                 while (parents) {
 384                         struct commit *p = parents->item;
 385                         parse_commit(p);
 386                         if (!(p->object.flags & SEEN))
 387                                 commit_list_insert_by_date(p, &list);
 388                         p->object.flags |= c->object.flags;
 389                         parents = parents->next;
 390
 391                         if (first_parent)
 392                                 break;
 393                 }
 394         }
 395
 396         if (!match_cnt) {
 397                 struct object_id *cmit_oid = &cmit->object.oid;
 398                 if (always) {
 399                         strbuf_add_unique_abbrev(dst, cmit_oid, abbrev);
 400                         if (suffix)
 401                                 strbuf_addstr(dst, suffix);
 402                         return;
 403                 }
 404                 if (unannotated_cnt)
 405                         die(_("No annotated tags can describe '%s'.\n"
 406                             "However, there were unannotated tags: try --tags."),
 407                             oid_to_hex(cmit_oid));
 408                 else
 409                         die(_("No tags can describe '%s'.\n"
 410                             "Try --always, or create some tags."),
 411                             oid_to_hex(cmit_oid));
 412         }
 413
 414         QSORT(all_matches, match_cnt, compare_pt);
 415
 416         if (gave_up_on) {
 417                 commit_list_insert_by_date(gave_up_on, &list);
 418                 seen_commits--;
 419         }
 420         seen_commits += finish_depth_computation(&list, &all_matches[0]);
 421         free_commit_list(list);
 422
 423         if (debug) {
 424                 static int label_width = -1;
 425                 if (label_width < 0) {
 426                         int i, w;
 427                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
 428                                 w = strlen(_(prio_names[i]));
 429                                 if (label_width < w)
 430                                         label_width = w;
 431                         }
 432                 }
 433                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 434                         struct possible_tag *t = &all_matches[cur_match];
 435                         fprintf(stderr, " %-*s %8d %s\n",
 436                                 label_width, _(prio_names[t->name->prio]),
 437                                 t->depth, t->name->path);
 438                 }
 439                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
 440                 if (gave_up_on) {
 441                         fprintf(stderr,
 442                                 _("more than %i tags found; listed %i most recent\n"
 443                                 "gave up search at %s\n"),
 444                                 max_candidates, max_candidates,
 445                                 oid_to_hex(&gave_up_on->object.oid));
 446                 }
 447         }
 448
 449         append_name(all_matches[0].name, dst);
 450         if (abbrev)
 451                 append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
 452         if (suffix)
 453                 strbuf_addstr(dst, suffix);
 454 }
 455
 456 struct process_commit_data {
 457         struct object_id current_commit;
 458         struct object_id looking_for;
 459         struct strbuf *dst;
 460         struct rev_info *revs;
 461 };
 462
 463 static void process_commit(struct commit *commit, void *data)
 464 {
 465         struct process_commit_data *pcd = data;
 466         pcd->current_commit = commit->object.oid;
 467 }
 468
 469 static void process_object(struct object *obj, const char *path, void *data)
 470 {
 471         struct process_commit_data *pcd = data;
 472
 473         if (oideq(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
 474                 reset_revision_walk();
 475                 describe_commit(&pcd->current_commit, pcd->dst);
 476                 strbuf_addf(pcd->dst, ":%s", path);
 477                 free_commit_list(pcd->revs->commits);
 478                 pcd->revs->commits = NULL;
 479         }
 480 }
 481
 482 static void describe_blob(struct object_id oid, struct strbuf *dst)
 483 {
 484         struct rev_info revs;
 485         struct argv_array args = ARGV_ARRAY_INIT;
 486         struct process_commit_data pcd = { null_oid, oid, dst, &revs};
 487
 488         argv_array_pushl(&args, "internal: The first arg is not parsed",
 489                 "--objects", "--in-commit-order", "--reverse", "HEAD",
 490                 NULL);
 491
 492         repo_init_revisions(the_repository, &revs, NULL);
 493         if (setup_revisions(args.argc, args.argv, &revs, NULL) > 1)
 494                 BUG("setup_revisions could not handle all args?");
 495
 496         if (prepare_revision_walk(&revs))
 497                 die("revision walk setup failed");
 498
 499         traverse_commit_list(&revs, process_commit, process_object, &pcd);
 500         reset_revision_walk();
 501 }
 502
 503 static void describe(const char *arg, int last_one)
 504 {
 505         struct object_id oid;
 506         struct commit *cmit;
 507         struct strbuf sb = STRBUF_INIT;
 508
 509         if (debug)
 510                 fprintf(stderr, _("describe %s\n"), arg);
 511
 512         if (get_oid(arg, &oid))
 513                 die(_("Not a valid object name %s"), arg);
 514         cmit = lookup_commit_reference_gently(the_repository, &oid, 1);
 515
 516         if (cmit)
 517                 describe_commit(&oid, &sb);
 518         else if (oid_object_info(the_repository, &oid, NULL) == OBJ_BLOB)
 519                 describe_blob(oid, &sb);
 520         else
 521                 die(_("%s is neither a commit nor blob"), arg);
 522
 523         puts(sb.buf);
 524
 525         if (!last_one)
 526                 clear_commit_marks(cmit, -1);
 527
 528         strbuf_release(&sb);
 529 }
 530
 531 int cmd_describe(int argc, const char **argv, const char *prefix)
 532 {
 533         int contains = 0;
 534         struct option options[] = {
 535                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
 536                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
 537                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
 538                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
 539                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
 540                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
 541                 OPT__ABBREV(&abbrev),
 542                 OPT_SET_INT(0, "exact-match", &max_candidates,
 543                             N_("only output exact matches"), 0),
 544                 OPT_INTEGER(0, "candidates", &max_candidates,
 545                             N_("consider <n> most recent tags (default: 10)")),
 546                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
 547                            N_("only consider tags matching <pattern>")),
 548                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
 549                            N_("do not consider tags matching <pattern>")),
 550                 OPT_BOOL(0, "always",        &always,
 551                         N_("show abbreviated commit object as fallback")),
 552                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
 553                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
 554                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
 555                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
 556                         N_("append <mark> on broken working tree (default: \"-broken\")"),
 557                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
 558                 OPT_END(),
 559         };
 560
 561         git_config(git_default_config, NULL);
 562         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
 563         if (abbrev < 0)
 564                 abbrev = DEFAULT_ABBREV;
 565
 566         if (max_candidates < 0)
 567                 max_candidates = 0;
 568         else if (max_candidates > MAX_TAGS)
 569                 max_candidates = MAX_TAGS;
 570
 571         save_commit_buffer = 0;
 572
 573         if (longformat && abbrev == 0)
 574                 die(_("--long is incompatible with --abbrev=0"));
 575
 576         if (contains) {
 577                 struct string_list_item *item;
 578                 struct argv_array args;
 579
 580                 argv_array_init(&args);
 581                 argv_array_pushl(&args, "name-rev",
 582                                  "--peel-tag", "--name-only", "--no-undefined",
 583                                  NULL);
 584                 if (always)
 585                         argv_array_push(&args, "--always");
 586                 if (!all) {
 587                         argv_array_push(&args, "--tags");
 588                         for_each_string_list_item(item, &patterns)
 589                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
 590                         for_each_string_list_item(item, &exclude_patterns)
 591                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
 592                 }
 593                 if (argc)
 594                         argv_array_pushv(&args, argv);
 595                 else
 596                         argv_array_push(&args, "HEAD");
 597                 return cmd_name_rev(args.argc, args.argv, prefix);
 598         }
 599
 600         hashmap_init(&names, commit_name_neq, NULL, 0);
 601         for_each_rawref(get_name, NULL);
 602         if (!hashmap_get_size(&names) && !always)
 603                 die(_("No names found, cannot describe anything."));
 604
 605         if (argc == 0) {
 606                 if (broken) {
 607                         struct child_process cp = CHILD_PROCESS_INIT;
 608                         argv_array_pushv(&cp.args, diff_index_args);
 609                         cp.git_cmd = 1;
 610                         cp.no_stdin = 1;
 611                         cp.no_stdout = 1;
 612
 613                         if (!dirty)
 614                                 dirty = "-dirty";
 615
 616                         switch (run_command(&cp)) {
 617                         case 0:
 618                                 suffix = NULL;
 619                                 break;
 620                         case 1:
 621                                 suffix = dirty;
 622                                 break;
 623                         default:
 624                                 /* diff-index aborted abnormally */
 625                                 suffix = broken;
 626                         }
 627                 } else if (dirty) {
 628                         struct lock_file index_lock = LOCK_INIT;
 629                         struct rev_info revs;
 630                         struct argv_array args = ARGV_ARRAY_INIT;
 631                         int fd, result;
 632
 633                         setup_work_tree();
 634                         read_cache();
 635                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
 636                                       NULL, NULL, NULL);
 637                         fd = hold_locked_index(&index_lock, 0);
 638                         if (0 <= fd)
 639                                 repo_update_index_if_able(the_repository, &index_lock);
 640
 641                         repo_init_revisions(the_repository, &revs, prefix);
 642                         argv_array_pushv(&args, diff_index_args);
 643                         if (setup_revisions(args.argc, args.argv, &revs, NULL) != 1)
 644                                 BUG("malformed internal diff-index command line");
 645                         result = run_diff_index(&revs, 0);
 646
 647                         if (!diff_result_code(&revs.diffopt, result))
 648                                 suffix = NULL;
 649                         else
 650                                 suffix = dirty;
 651                 }
 652                 describe("HEAD", 1);
 653         } else if (dirty) {
 654                 die(_("--dirty is incompatible with commit-ishes"));
 655         } else if (broken) {
 656                 die(_("--broken is incompatible with commit-ishes"));
 657         } else {
 658                 while (argc-- > 0)
 659                         describe(*argv++, argc == 0);
 660         }
 661         return 0;
 662 }