builtin/describe.c

   1 #include "cache.h"
   2 #include "lockfile.h"
   3 #include "commit.h"
   4 #include "tag.h"
   5 #include "refs.h"
   6 #include "builtin.h"
   7 #include "exec_cmd.h"
   8 #include "parse-options.h"
   9 #include "diff.h"
  10 #include "hashmap.h"
  11 #include "argv-array.h"
  12 #include "run-command.h"
  13
  14 #define SEEN            (1u << 0)
  15 #define MAX_TAGS        (FLAG_BITS - 1)
  16
  17 static const char * const describe_usage[] = {
  18         N_("git describe [<options>] [<commit-ish>...]"),
  19         N_("git describe [<options>] --dirty"),
  20         NULL
  21 };
  22
  23 static int debug;       /* Display lots of verbose info */
  24 static int all; /* Any valid ref can be used */
  25 static int tags;        /* Allow lightweight tags */
  26 static int longformat;
  27 static int first_parent;
  28 static int abbrev = -1; /* unspecified */
  29 static int max_candidates = 10;
  30 static struct hashmap names;
  31 static int have_util;
  32 static struct string_list patterns = STRING_LIST_INIT_NODUP;
  33 static struct string_list exclude_patterns = STRING_LIST_INIT_NODUP;
  34 static int always;
  35 static const char *suffix, *dirty, *broken;
  36
  37 /* diff-index command arguments to check if working tree is dirty. */
  38 static const char *diff_index_args[] = {
  39         "diff-index", "--quiet", "HEAD", "--", NULL
  40 };
  41
  42 struct commit_name {
  43         struct hashmap_entry entry;
  44         struct object_id peeled;
  45         struct tag *tag;
  46         unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
  47         unsigned name_checked:1;
  48         struct object_id oid;
  49         char *path;
  50 };
  51
  52 static const char *prio_names[] = {
  53         "head", "lightweight", "annotated",
  54 };
  55
  56 static int commit_name_cmp(const struct commit_name *cn1,
  57                 const struct commit_name *cn2, const void *peeled)
  58 {
  59         return oidcmp(&cn1->peeled, peeled ? peeled : &cn2->peeled);
  60 }
  61
  62 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
  63 {
  64         return hashmap_get_from_hash(&names, sha1hash(peeled->hash), peeled->hash);
  65 }
  66
  67 static int replace_name(struct commit_name *e,
  68                                int prio,
  69                                const struct object_id *oid,
  70                                struct tag **tag)
  71 {
  72         if (!e || e->prio < prio)
  73                 return 1;
  74
  75         if (e->prio == 2 && prio == 2) {
  76                 /* Multiple annotated tags point to the same commit.
  77                  * Select one to keep based upon their tagger date.
  78                  */
  79                 struct tag *t;
  80
  81                 if (!e->tag) {
  82                         t = lookup_tag(e->oid.hash);
  83                         if (!t || parse_tag(t))
  84                                 return 1;
  85                         e->tag = t;
  86                 }
  87
  88                 t = lookup_tag(oid->hash);
  89                 if (!t || parse_tag(t))
  90                         return 0;
  91                 *tag = t;
  92
  93                 if (e->tag->date < t->date)
  94                         return 1;
  95         }
  96
  97         return 0;
  98 }
  99
 100 static void add_to_known_names(const char *path,
 101                                const struct object_id *peeled,
 102                                int prio,
 103                                const struct object_id *oid)
 104 {
 105         struct commit_name *e = find_commit_name(peeled);
 106         struct tag *tag = NULL;
 107         if (replace_name(e, prio, oid, &tag)) {
 108                 if (!e) {
 109                         e = xmalloc(sizeof(struct commit_name));
 110                         oidcpy(&e->peeled, peeled);
 111                         hashmap_entry_init(e, sha1hash(peeled->hash));
 112                         hashmap_add(&names, e);
 113                         e->path = NULL;
 114                 }
 115                 e->tag = tag;
 116                 e->prio = prio;
 117                 e->name_checked = 0;
 118                 oidcpy(&e->oid, oid);
 119                 free(e->path);
 120                 e->path = xstrdup(path);
 121         }
 122 }
 123
 124 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
 125 {
 126         int is_tag = starts_with(path, "refs/tags/");
 127         struct object_id peeled;
 128         int is_annotated, prio;
 129
 130         /* Reject anything outside refs/tags/ unless --all */
 131         if (!all && !is_tag)
 132                 return 0;
 133
 134         /*
 135          * If we're given exclude patterns, first exclude any tag which match
 136          * any of the exclude pattern.
 137          */
 138         if (exclude_patterns.nr) {
 139                 struct string_list_item *item;
 140
 141                 if (!is_tag)
 142                         return 0;
 143
 144                 for_each_string_list_item(item, &exclude_patterns) {
 145                         if (!wildmatch(item->string, path + 10, 0, NULL))
 146                                 return 0;
 147                 }
 148         }
 149
 150         /*
 151          * If we're given patterns, accept only tags which match at least one
 152          * pattern.
 153          */
 154         if (patterns.nr) {
 155                 struct string_list_item *item;
 156
 157                 if (!is_tag)
 158                         return 0;
 159
 160                 for_each_string_list_item(item, &patterns) {
 161                         if (!wildmatch(item->string, path + 10, 0, NULL))
 162                                 break;
 163
 164                         /* If we get here, no pattern matched. */
 165                         return 0;
 166                 }
 167         }
 168
 169         /* Is it annotated? */
 170         if (!peel_ref(path, peeled.hash)) {
 171                 is_annotated = !!oidcmp(oid, &peeled);
 172         } else {
 173                 oidcpy(&peeled, oid);
 174                 is_annotated = 0;
 175         }
 176
 177         /*
 178          * By default, we only use annotated tags, but with --tags
 179          * we fall back to lightweight ones (even without --tags,
 180          * we still remember lightweight ones, only to give hints
 181          * in an error message).  --all allows any refs to be used.
 182          */
 183         if (is_annotated)
 184                 prio = 2;
 185         else if (is_tag)
 186                 prio = 1;
 187         else
 188                 prio = 0;
 189
 190         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
 191         return 0;
 192 }
 193
 194 struct possible_tag {
 195         struct commit_name *name;
 196         int depth;
 197         int found_order;
 198         unsigned flag_within;
 199 };
 200
 201 static int compare_pt(const void *a_, const void *b_)
 202 {
 203         struct possible_tag *a = (struct possible_tag *)a_;
 204         struct possible_tag *b = (struct possible_tag *)b_;
 205         if (a->depth != b->depth)
 206                 return a->depth - b->depth;
 207         if (a->found_order != b->found_order)
 208                 return a->found_order - b->found_order;
 209         return 0;
 210 }
 211
 212 static unsigned long finish_depth_computation(
 213         struct commit_list **list,
 214         struct possible_tag *best)
 215 {
 216         unsigned long seen_commits = 0;
 217         while (*list) {
 218                 struct commit *c = pop_commit(list);
 219                 struct commit_list *parents = c->parents;
 220                 seen_commits++;
 221                 if (c->object.flags & best->flag_within) {
 222                         struct commit_list *a = *list;
 223                         while (a) {
 224                                 struct commit *i = a->item;
 225                                 if (!(i->object.flags & best->flag_within))
 226                                         break;
 227                                 a = a->next;
 228                         }
 229                         if (!a)
 230                                 break;
 231                 } else
 232                         best->depth++;
 233                 while (parents) {
 234                         struct commit *p = parents->item;
 235                         parse_commit(p);
 236                         if (!(p->object.flags & SEEN))
 237                                 commit_list_insert_by_date(p, list);
 238                         p->object.flags |= c->object.flags;
 239                         parents = parents->next;
 240                 }
 241         }
 242         return seen_commits;
 243 }
 244
 245 static void display_name(struct commit_name *n)
 246 {
 247         if (n->prio == 2 && !n->tag) {
 248                 n->tag = lookup_tag(n->oid.hash);
 249                 if (!n->tag || parse_tag(n->tag))
 250                         die(_("annotated tag %s not available"), n->path);
 251         }
 252         if (n->tag && !n->name_checked) {
 253                 if (!n->tag->tag)
 254                         die(_("annotated tag %s has no embedded name"), n->path);
 255                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
 256                         warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
 257                 n->name_checked = 1;
 258         }
 259
 260         if (n->tag)
 261                 printf("%s", n->tag->tag);
 262         else
 263                 printf("%s", n->path);
 264 }
 265
 266 static void show_suffix(int depth, const struct object_id *oid)
 267 {
 268         printf("-%d-g%s", depth, find_unique_abbrev(oid->hash, abbrev));
 269 }
 270
 271 static void describe(const char *arg, int last_one)
 272 {
 273         struct object_id oid;
 274         struct commit *cmit, *gave_up_on = NULL;
 275         struct commit_list *list;
 276         struct commit_name *n;
 277         struct possible_tag all_matches[MAX_TAGS];
 278         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
 279         unsigned long seen_commits = 0;
 280         unsigned int unannotated_cnt = 0;
 281
 282         if (get_oid(arg, &oid))
 283                 die(_("Not a valid object name %s"), arg);
 284         cmit = lookup_commit_reference(oid.hash);
 285         if (!cmit)
 286                 die(_("%s is not a valid '%s' object"), arg, commit_type);
 287
 288         n = find_commit_name(&cmit->object.oid);
 289         if (n && (tags || all || n->prio == 2)) {
 290                 /*
 291                  * Exact match to an existing ref.
 292                  */
 293                 display_name(n);
 294                 if (longformat)
 295                         show_suffix(0, n->tag ? &n->tag->tagged->oid : &oid);
 296                 if (suffix)
 297                         printf("%s", suffix);
 298                 printf("\n");
 299                 return;
 300         }
 301
 302         if (!max_candidates)
 303                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
 304         if (debug)
 305                 fprintf(stderr, _("searching to describe %s\n"), arg);
 306
 307         if (!have_util) {
 308                 struct hashmap_iter iter;
 309                 struct commit *c;
 310                 struct commit_name *n = hashmap_iter_first(&names, &iter);
 311                 for (; n; n = hashmap_iter_next(&iter)) {
 312                         c = lookup_commit_reference_gently(n->peeled.hash, 1);
 313                         if (c)
 314                                 c->util = n;
 315                 }
 316                 have_util = 1;
 317         }
 318
 319         list = NULL;
 320         cmit->object.flags = SEEN;
 321         commit_list_insert(cmit, &list);
 322         while (list) {
 323                 struct commit *c = pop_commit(&list);
 324                 struct commit_list *parents = c->parents;
 325                 seen_commits++;
 326                 n = c->util;
 327                 if (n) {
 328                         if (!tags && !all && n->prio < 2) {
 329                                 unannotated_cnt++;
 330                         } else if (match_cnt < max_candidates) {
 331                                 struct possible_tag *t = &all_matches[match_cnt++];
 332                                 t->name = n;
 333                                 t->depth = seen_commits - 1;
 334                                 t->flag_within = 1u << match_cnt;
 335                                 t->found_order = match_cnt;
 336                                 c->object.flags |= t->flag_within;
 337                                 if (n->prio == 2)
 338                                         annotated_cnt++;
 339                         }
 340                         else {
 341                                 gave_up_on = c;
 342                                 break;
 343                         }
 344                 }
 345                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 346                         struct possible_tag *t = &all_matches[cur_match];
 347                         if (!(c->object.flags & t->flag_within))
 348                                 t->depth++;
 349                 }
 350                 if (annotated_cnt && !list) {
 351                         if (debug)
 352                                 fprintf(stderr, _("finished search at %s\n"),
 353                                         oid_to_hex(&c->object.oid));
 354                         break;
 355                 }
 356                 while (parents) {
 357                         struct commit *p = parents->item;
 358                         parse_commit(p);
 359                         if (!(p->object.flags & SEEN))
 360                                 commit_list_insert_by_date(p, &list);
 361                         p->object.flags |= c->object.flags;
 362                         parents = parents->next;
 363
 364                         if (first_parent)
 365                                 break;
 366                 }
 367         }
 368
 369         if (!match_cnt) {
 370                 struct object_id *oid = &cmit->object.oid;
 371                 if (always) {
 372                         printf("%s", find_unique_abbrev(oid->hash, abbrev));
 373                         if (suffix)
 374                                 printf("%s", suffix);
 375                         printf("\n");
 376                         return;
 377                 }
 378                 if (unannotated_cnt)
 379                         die(_("No annotated tags can describe '%s'.\n"
 380                             "However, there were unannotated tags: try --tags."),
 381                             oid_to_hex(oid));
 382                 else
 383                         die(_("No tags can describe '%s'.\n"
 384                             "Try --always, or create some tags."),
 385                             oid_to_hex(oid));
 386         }
 387
 388         QSORT(all_matches, match_cnt, compare_pt);
 389
 390         if (gave_up_on) {
 391                 commit_list_insert_by_date(gave_up_on, &list);
 392                 seen_commits--;
 393         }
 394         seen_commits += finish_depth_computation(&list, &all_matches[0]);
 395         free_commit_list(list);
 396
 397         if (debug) {
 398                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 399                         struct possible_tag *t = &all_matches[cur_match];
 400                         fprintf(stderr, " %-11s %8d %s\n",
 401                                 prio_names[t->name->prio],
 402                                 t->depth, t->name->path);
 403                 }
 404                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
 405                 if (gave_up_on) {
 406                         fprintf(stderr,
 407                                 _("more than %i tags found; listed %i most recent\n"
 408                                 "gave up search at %s\n"),
 409                                 max_candidates, max_candidates,
 410                                 oid_to_hex(&gave_up_on->object.oid));
 411                 }
 412         }
 413
 414         display_name(all_matches[0].name);
 415         if (abbrev)
 416                 show_suffix(all_matches[0].depth, &cmit->object.oid);
 417         if (suffix)
 418                 printf("%s", suffix);
 419         printf("\n");
 420
 421         if (!last_one)
 422                 clear_commit_marks(cmit, -1);
 423 }
 424
 425 int cmd_describe(int argc, const char **argv, const char *prefix)
 426 {
 427         int contains = 0;
 428         struct option options[] = {
 429                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
 430                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
 431                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
 432                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
 433                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
 434                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
 435                 OPT__ABBREV(&abbrev),
 436                 OPT_SET_INT(0, "exact-match", &max_candidates,
 437                             N_("only output exact matches"), 0),
 438                 OPT_INTEGER(0, "candidates", &max_candidates,
 439                             N_("consider <n> most recent tags (default: 10)")),
 440                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
 441                            N_("only consider tags matching <pattern>")),
 442                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
 443                            N_("do not consider tags matching <pattern>")),
 444                 OPT_BOOL(0, "always",        &always,
 445                         N_("show abbreviated commit object as fallback")),
 446                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
 447                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
 448                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
 449                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
 450                         N_("append <mark> on broken working tree (default: \"-broken\")"),
 451                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
 452                 OPT_END(),
 453         };
 454
 455         git_config(git_default_config, NULL);
 456         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
 457         if (abbrev < 0)
 458                 abbrev = DEFAULT_ABBREV;
 459
 460         if (max_candidates < 0)
 461                 max_candidates = 0;
 462         else if (max_candidates > MAX_TAGS)
 463                 max_candidates = MAX_TAGS;
 464
 465         save_commit_buffer = 0;
 466
 467         if (longformat && abbrev == 0)
 468                 die(_("--long is incompatible with --abbrev=0"));
 469
 470         if (contains) {
 471                 struct string_list_item *item;
 472                 struct argv_array args;
 473
 474                 argv_array_init(&args);
 475                 argv_array_pushl(&args, "name-rev",
 476                                  "--peel-tag", "--name-only", "--no-undefined",
 477                                  NULL);
 478                 if (always)
 479                         argv_array_push(&args, "--always");
 480                 if (!all) {
 481                         argv_array_push(&args, "--tags");
 482                         for_each_string_list_item(item, &patterns)
 483                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
 484                         for_each_string_list_item(item, &exclude_patterns)
 485                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
 486                 }
 487                 if (argc)
 488                         argv_array_pushv(&args, argv);
 489                 else
 490                         argv_array_push(&args, "HEAD");
 491                 return cmd_name_rev(args.argc, args.argv, prefix);
 492         }
 493
 494         hashmap_init(&names, (hashmap_cmp_fn) commit_name_cmp, 0);
 495         for_each_rawref(get_name, NULL);
 496         if (!names.size && !always)
 497                 die(_("No names found, cannot describe anything."));
 498
 499         if (argc == 0) {
 500                 if (broken) {
 501                         struct child_process cp = CHILD_PROCESS_INIT;
 502                         argv_array_pushv(&cp.args, diff_index_args);
 503                         cp.git_cmd = 1;
 504                         cp.no_stdin = 1;
 505                         cp.no_stdout = 1;
 506
 507                         if (!dirty)
 508                                 dirty = "-dirty";
 509
 510                         switch (run_command(&cp)) {
 511                         case 0:
 512                                 suffix = NULL;
 513                                 break;
 514                         case 1:
 515                                 suffix = dirty;
 516                                 break;
 517                         default:
 518                                 /* diff-index aborted abnormally */
 519                                 suffix = broken;
 520                         }
 521                 } else if (dirty) {
 522                         static struct lock_file index_lock;
 523                         int fd;
 524
 525                         read_cache_preload(NULL);
 526                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
 527                                       NULL, NULL, NULL);
 528                         fd = hold_locked_index(&index_lock, 0);
 529                         if (0 <= fd)
 530                                 update_index_if_able(&the_index, &index_lock);
 531
 532                         if (!cmd_diff_index(ARRAY_SIZE(diff_index_args) - 1,
 533                                             diff_index_args, prefix))
 534                                 suffix = NULL;
 535                         else
 536                                 suffix = dirty;
 537                 }
 538                 describe("HEAD", 1);
 539         } else if (dirty) {
 540                 die(_("--dirty is incompatible with commit-ishes"));
 541         } else if (broken) {
 542                 die(_("--broken is incompatible with commit-ishes"));
 543         } else {
 544                 while (argc-- > 0)
 545                         describe(*argv++, argc == 0);
 546         }
 547         return 0;
 548 }