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