builtin/describe.c

   1 #define USE_THE_INDEX_VARIABLE
   2 #include "cache.h"
   3 #include "config.h"
   4 #include "environment.h"
   5 #include "gettext.h"
   6 #include "hex.h"
   7 #include "lockfile.h"
   8 #include "commit.h"
   9 #include "tag.h"
  10 #include "blob.h"
  11 #include "refs.h"
  12 #include "builtin.h"
  13 #include "exec-cmd.h"
  14 #include "parse-options.h"
  15 #include "revision.h"
  16 #include "diff.h"
  17 #include "hashmap.h"
  18 #include "setup.h"
  19 #include "strvec.h"
  20 #include "run-command.h"
  21 #include "object-store.h"
  22 #include "list-objects.h"
  23 #include "commit-slab.h"
  24
  25 #define MAX_TAGS        (FLAG_BITS - 1)
  26
  27 define_commit_slab(commit_names, struct commit_name *);
  28
  29 static const char * const describe_usage[] = {
  30         N_("git describe [--all] [--tags] [--contains] [--abbrev=<n>] [<commit-ish>...]"),
  31         N_("git describe [--all] [--tags] [--contains] [--abbrev=<n>] --dirty[=<mark>]"),
  32         N_("git describe <blob>"),
  33         NULL
  34 };
  35
  36 static int debug;       /* Display lots of verbose info */
  37 static int all; /* Any valid ref can be used */
  38 static int tags;        /* Allow lightweight tags */
  39 static int longformat;
  40 static int first_parent;
  41 static int abbrev = -1; /* unspecified */
  42 static int max_candidates = 10;
  43 static struct hashmap names;
  44 static int have_util;
  45 static struct string_list patterns = STRING_LIST_INIT_NODUP;
  46 static struct string_list exclude_patterns = STRING_LIST_INIT_NODUP;
  47 static int always;
  48 static const char *suffix, *dirty, *broken;
  49 static struct commit_names commit_names;
  50
  51 /* diff-index command arguments to check if working tree is dirty. */
  52 static const char *diff_index_args[] = {
  53         "diff-index", "--quiet", "HEAD", "--", NULL
  54 };
  55
  56 struct commit_name {
  57         struct hashmap_entry entry;
  58         struct object_id peeled;
  59         struct tag *tag;
  60         unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
  61         unsigned name_checked:1;
  62         unsigned misnamed:1;
  63         struct object_id oid;
  64         char *path;
  65 };
  66
  67 static const char *prio_names[] = {
  68         N_("head"), N_("lightweight"), N_("annotated"),
  69 };
  70
  71 static int commit_name_neq(const void *cmp_data UNUSED,
  72                            const struct hashmap_entry *eptr,
  73                            const struct hashmap_entry *entry_or_key,
  74                            const void *peeled)
  75 {
  76         const struct commit_name *cn1, *cn2;
  77
  78         cn1 = container_of(eptr, const struct commit_name, entry);
  79         cn2 = container_of(entry_or_key, const struct commit_name, entry);
  80
  81         return !oideq(&cn1->peeled, peeled ? peeled : &cn2->peeled);
  82 }
  83
  84 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
  85 {
  86         return hashmap_get_entry_from_hash(&names, oidhash(peeled), peeled,
  87                                                 struct commit_name, entry);
  88 }
  89
  90 static int replace_name(struct commit_name *e,
  91                                int prio,
  92                                const struct object_id *oid,
  93                                struct tag **tag)
  94 {
  95         if (!e || e->prio < prio)
  96                 return 1;
  97
  98         if (e->prio == 2 && prio == 2) {
  99                 /* Multiple annotated tags point to the same commit.
 100                  * Select one to keep based upon their tagger date.
 101                  */
 102                 struct tag *t;
 103
 104                 if (!e->tag) {
 105                         t = lookup_tag(the_repository, &e->oid);
 106                         if (!t || parse_tag(t))
 107                                 return 1;
 108                         e->tag = t;
 109                 }
 110
 111                 t = lookup_tag(the_repository, oid);
 112                 if (!t || parse_tag(t))
 113                         return 0;
 114                 *tag = t;
 115
 116                 if (e->tag->date < t->date)
 117                         return 1;
 118         }
 119
 120         return 0;
 121 }
 122
 123 static void add_to_known_names(const char *path,
 124                                const struct object_id *peeled,
 125                                int prio,
 126                                const struct object_id *oid)
 127 {
 128         struct commit_name *e = find_commit_name(peeled);
 129         struct tag *tag = NULL;
 130         if (replace_name(e, prio, oid, &tag)) {
 131                 if (!e) {
 132                         e = xmalloc(sizeof(struct commit_name));
 133                         oidcpy(&e->peeled, peeled);
 134                         hashmap_entry_init(&e->entry, oidhash(peeled));
 135                         hashmap_add(&names, &e->entry);
 136                         e->path = NULL;
 137                 }
 138                 e->tag = tag;
 139                 e->prio = prio;
 140                 e->name_checked = 0;
 141                 e->misnamed = 0;
 142                 oidcpy(&e->oid, oid);
 143                 free(e->path);
 144                 e->path = xstrdup(path);
 145         }
 146 }
 147
 148 static int get_name(const char *path, const struct object_id *oid,
 149                     int flag UNUSED, void *cb_data UNUSED)
 150 {
 151         int is_tag = 0;
 152         struct object_id peeled;
 153         int is_annotated, prio;
 154         const char *path_to_match = NULL;
 155
 156         if (skip_prefix(path, "refs/tags/", &path_to_match)) {
 157                 is_tag = 1;
 158         } else if (all) {
 159                 if ((exclude_patterns.nr || patterns.nr) &&
 160                     !skip_prefix(path, "refs/heads/", &path_to_match) &&
 161                     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
 162                         /* Only accept reference of known type if there are match/exclude patterns */
 163                         return 0;
 164                 }
 165         } else {
 166                 /* Reject anything outside refs/tags/ unless --all */
 167                 return 0;
 168         }
 169
 170         /*
 171          * If we're given exclude patterns, first exclude any tag which match
 172          * any of the exclude pattern.
 173          */
 174         if (exclude_patterns.nr) {
 175                 struct string_list_item *item;
 176
 177                 for_each_string_list_item(item, &exclude_patterns) {
 178                         if (!wildmatch(item->string, path_to_match, 0))
 179                                 return 0;
 180                 }
 181         }
 182
 183         /*
 184          * If we're given patterns, accept only tags which match at least one
 185          * pattern.
 186          */
 187         if (patterns.nr) {
 188                 int found = 0;
 189                 struct string_list_item *item;
 190
 191                 for_each_string_list_item(item, &patterns) {
 192                         if (!wildmatch(item->string, path_to_match, 0)) {
 193                                 found = 1;
 194                                 break;
 195                         }
 196                 }
 197
 198                 if (!found)
 199                         return 0;
 200         }
 201
 202         /* Is it annotated? */
 203         if (!peel_iterated_oid(oid, &peeled)) {
 204                 is_annotated = !oideq(oid, &peeled);
 205         } else {
 206                 oidcpy(&peeled, oid);
 207                 is_annotated = 0;
 208         }
 209
 210         /*
 211          * By default, we only use annotated tags, but with --tags
 212          * we fall back to lightweight ones (even without --tags,
 213          * we still remember lightweight ones, only to give hints
 214          * in an error message).  --all allows any refs to be used.
 215          */
 216         if (is_annotated)
 217                 prio = 2;
 218         else if (is_tag)
 219                 prio = 1;
 220         else
 221                 prio = 0;
 222
 223         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
 224         return 0;
 225 }
 226
 227 struct possible_tag {
 228         struct commit_name *name;
 229         int depth;
 230         int found_order;
 231         unsigned flag_within;
 232 };
 233
 234 static int compare_pt(const void *a_, const void *b_)
 235 {
 236         struct possible_tag *a = (struct possible_tag *)a_;
 237         struct possible_tag *b = (struct possible_tag *)b_;
 238         if (a->depth != b->depth)
 239                 return a->depth - b->depth;
 240         if (a->found_order != b->found_order)
 241                 return a->found_order - b->found_order;
 242         return 0;
 243 }
 244
 245 static unsigned long finish_depth_computation(
 246         struct commit_list **list,
 247         struct possible_tag *best)
 248 {
 249         unsigned long seen_commits = 0;
 250         while (*list) {
 251                 struct commit *c = pop_commit(list);
 252                 struct commit_list *parents = c->parents;
 253                 seen_commits++;
 254                 if (c->object.flags & best->flag_within) {
 255                         struct commit_list *a = *list;
 256                         while (a) {
 257                                 struct commit *i = a->item;
 258                                 if (!(i->object.flags & best->flag_within))
 259                                         break;
 260                                 a = a->next;
 261                         }
 262                         if (!a)
 263                                 break;
 264                 } else
 265                         best->depth++;
 266                 while (parents) {
 267                         struct commit *p = parents->item;
 268                         parse_commit(p);
 269                         if (!(p->object.flags & SEEN))
 270                                 commit_list_insert_by_date(p, list);
 271                         p->object.flags |= c->object.flags;
 272                         parents = parents->next;
 273                 }
 274         }
 275         return seen_commits;
 276 }
 277
 278 static void append_name(struct commit_name *n, struct strbuf *dst)
 279 {
 280         if (n->prio == 2 && !n->tag) {
 281                 n->tag = lookup_tag(the_repository, &n->oid);
 282                 if (!n->tag || parse_tag(n->tag))
 283                         die(_("annotated tag %s not available"), n->path);
 284         }
 285         if (n->tag && !n->name_checked) {
 286                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path)) {
 287                         warning(_("tag '%s' is externally known as '%s'"),
 288                                 n->path, n->tag->tag);
 289                         n->misnamed = 1;
 290                 }
 291                 n->name_checked = 1;
 292         }
 293
 294         if (n->tag) {
 295                 if (all)
 296                         strbuf_addstr(dst, "tags/");
 297                 strbuf_addstr(dst, n->tag->tag);
 298         } else {
 299                 strbuf_addstr(dst, n->path);
 300         }
 301 }
 302
 303 static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
 304 {
 305         strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid, abbrev));
 306 }
 307
 308 static void describe_commit(struct object_id *oid, struct strbuf *dst)
 309 {
 310         struct commit *cmit, *gave_up_on = NULL;
 311         struct commit_list *list;
 312         struct commit_name *n;
 313         struct possible_tag all_matches[MAX_TAGS];
 314         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
 315         unsigned long seen_commits = 0;
 316         unsigned int unannotated_cnt = 0;
 317
 318         cmit = lookup_commit_reference(the_repository, oid);
 319
 320         n = find_commit_name(&cmit->object.oid);
 321         if (n && (tags || all || n->prio == 2)) {
 322                 /*
 323                  * Exact match to an existing ref.
 324                  */
 325                 append_name(n, dst);
 326                 if (n->misnamed || longformat)
 327                         append_suffix(0, n->tag ? get_tagged_oid(n->tag) : oid, dst);
 328                 if (suffix)
 329                         strbuf_addstr(dst, suffix);
 330                 return;
 331         }
 332
 333         if (!max_candidates)
 334                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
 335         if (debug)
 336                 fprintf(stderr, _("No exact match on refs or tags, searching to describe\n"));
 337
 338         if (!have_util) {
 339                 struct hashmap_iter iter;
 340                 struct commit *c;
 341                 struct commit_name *n;
 342
 343                 init_commit_names(&commit_names);
 344                 hashmap_for_each_entry(&names, &iter, n,
 345                                         entry /* member name */) {
 346                         c = lookup_commit_reference_gently(the_repository,
 347                                                            &n->peeled, 1);
 348                         if (c)
 349                                 *commit_names_at(&commit_names, c) = n;
 350                 }
 351                 have_util = 1;
 352         }
 353
 354         list = NULL;
 355         cmit->object.flags = SEEN;
 356         commit_list_insert(cmit, &list);
 357         while (list) {
 358                 struct commit *c = pop_commit(&list);
 359                 struct commit_list *parents = c->parents;
 360                 struct commit_name **slot;
 361
 362                 seen_commits++;
 363                 slot = commit_names_peek(&commit_names, c);
 364                 n = slot ? *slot : NULL;
 365                 if (n) {
 366                         if (!tags && !all && n->prio < 2) {
 367                                 unannotated_cnt++;
 368                         } else if (match_cnt < max_candidates) {
 369                                 struct possible_tag *t = &all_matches[match_cnt++];
 370                                 t->name = n;
 371                                 t->depth = seen_commits - 1;
 372                                 t->flag_within = 1u << match_cnt;
 373                                 t->found_order = match_cnt;
 374                                 c->object.flags |= t->flag_within;
 375                                 if (n->prio == 2)
 376                                         annotated_cnt++;
 377                         }
 378                         else {
 379                                 gave_up_on = c;
 380                                 break;
 381                         }
 382                 }
 383                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 384                         struct possible_tag *t = &all_matches[cur_match];
 385                         if (!(c->object.flags & t->flag_within))
 386                                 t->depth++;
 387                 }
 388                 /* Stop if last remaining path already covered by best candidate(s) */
 389                 if (annotated_cnt && !list) {
 390                         int best_depth = INT_MAX;
 391                         unsigned best_within = 0;
 392                         for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 393                                 struct possible_tag *t = &all_matches[cur_match];
 394                                 if (t->depth < best_depth) {
 395                                         best_depth = t->depth;
 396                                         best_within = t->flag_within;
 397                                 } else if (t->depth == best_depth) {
 398                                         best_within |= t->flag_within;
 399                                 }
 400                         }
 401                         if ((c->object.flags & best_within) == best_within) {
 402                                 if (debug)
 403                                         fprintf(stderr, _("finished search at %s\n"),
 404                                                 oid_to_hex(&c->object.oid));
 405                                 break;
 406                         }
 407                 }
 408                 while (parents) {
 409                         struct commit *p = parents->item;
 410                         parse_commit(p);
 411                         if (!(p->object.flags & SEEN))
 412                                 commit_list_insert_by_date(p, &list);
 413                         p->object.flags |= c->object.flags;
 414                         parents = parents->next;
 415
 416                         if (first_parent)
 417                                 break;
 418                 }
 419         }
 420
 421         if (!match_cnt) {
 422                 struct object_id *cmit_oid = &cmit->object.oid;
 423                 if (always) {
 424                         strbuf_add_unique_abbrev(dst, cmit_oid, abbrev);
 425                         if (suffix)
 426                                 strbuf_addstr(dst, suffix);
 427                         return;
 428                 }
 429                 if (unannotated_cnt)
 430                         die(_("No annotated tags can describe '%s'.\n"
 431                             "However, there were unannotated tags: try --tags."),
 432                             oid_to_hex(cmit_oid));
 433                 else
 434                         die(_("No tags can describe '%s'.\n"
 435                             "Try --always, or create some tags."),
 436                             oid_to_hex(cmit_oid));
 437         }
 438
 439         QSORT(all_matches, match_cnt, compare_pt);
 440
 441         if (gave_up_on) {
 442                 commit_list_insert_by_date(gave_up_on, &list);
 443                 seen_commits--;
 444         }
 445         seen_commits += finish_depth_computation(&list, &all_matches[0]);
 446         free_commit_list(list);
 447
 448         if (debug) {
 449                 static int label_width = -1;
 450                 if (label_width < 0) {
 451                         int i, w;
 452                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
 453                                 w = strlen(_(prio_names[i]));
 454                                 if (label_width < w)
 455                                         label_width = w;
 456                         }
 457                 }
 458                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
 459                         struct possible_tag *t = &all_matches[cur_match];
 460                         fprintf(stderr, " %-*s %8d %s\n",
 461                                 label_width, _(prio_names[t->name->prio]),
 462                                 t->depth, t->name->path);
 463                 }
 464                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
 465                 if (gave_up_on) {
 466                         fprintf(stderr,
 467                                 _("more than %i tags found; listed %i most recent\n"
 468                                 "gave up search at %s\n"),
 469                                 max_candidates, max_candidates,
 470                                 oid_to_hex(&gave_up_on->object.oid));
 471                 }
 472         }
 473
 474         append_name(all_matches[0].name, dst);
 475         if (all_matches[0].name->misnamed || abbrev)
 476                 append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
 477         if (suffix)
 478                 strbuf_addstr(dst, suffix);
 479 }
 480
 481 struct process_commit_data {
 482         struct object_id current_commit;
 483         struct object_id looking_for;
 484         struct strbuf *dst;
 485         struct rev_info *revs;
 486 };
 487
 488 static void process_commit(struct commit *commit, void *data)
 489 {
 490         struct process_commit_data *pcd = data;
 491         pcd->current_commit = commit->object.oid;
 492 }
 493
 494 static void process_object(struct object *obj, const char *path, void *data)
 495 {
 496         struct process_commit_data *pcd = data;
 497
 498         if (oideq(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
 499                 reset_revision_walk();
 500                 describe_commit(&pcd->current_commit, pcd->dst);
 501                 strbuf_addf(pcd->dst, ":%s", path);
 502                 free_commit_list(pcd->revs->commits);
 503                 pcd->revs->commits = NULL;
 504         }
 505 }
 506
 507 static void describe_blob(struct object_id oid, struct strbuf *dst)
 508 {
 509         struct rev_info revs;
 510         struct strvec args = STRVEC_INIT;
 511         struct process_commit_data pcd = { *null_oid(), oid, dst, &revs};
 512
 513         strvec_pushl(&args, "internal: The first arg is not parsed",
 514                      "--objects", "--in-commit-order", "--reverse", "HEAD",
 515                      NULL);
 516
 517         repo_init_revisions(the_repository, &revs, NULL);
 518         if (setup_revisions(args.nr, args.v, &revs, NULL) > 1)
 519                 BUG("setup_revisions could not handle all args?");
 520
 521         if (prepare_revision_walk(&revs))
 522                 die("revision walk setup failed");
 523
 524         traverse_commit_list(&revs, process_commit, process_object, &pcd);
 525         reset_revision_walk();
 526         release_revisions(&revs);
 527 }
 528
 529 static void describe(const char *arg, int last_one)
 530 {
 531         struct object_id oid;
 532         struct commit *cmit;
 533         struct strbuf sb = STRBUF_INIT;
 534
 535         if (debug)
 536                 fprintf(stderr, _("describe %s\n"), arg);
 537
 538         if (get_oid(arg, &oid))
 539                 die(_("Not a valid object name %s"), arg);
 540         cmit = lookup_commit_reference_gently(the_repository, &oid, 1);
 541
 542         if (cmit)
 543                 describe_commit(&oid, &sb);
 544         else if (oid_object_info(the_repository, &oid, NULL) == OBJ_BLOB)
 545                 describe_blob(oid, &sb);
 546         else
 547                 die(_("%s is neither a commit nor blob"), arg);
 548
 549         puts(sb.buf);
 550
 551         if (!last_one)
 552                 clear_commit_marks(cmit, -1);
 553
 554         strbuf_release(&sb);
 555 }
 556
 557 int cmd_describe(int argc, const char **argv, const char *prefix)
 558 {
 559         int contains = 0;
 560         struct option options[] = {
 561                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
 562                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
 563                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
 564                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
 565                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
 566                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
 567                 OPT__ABBREV(&abbrev),
 568                 OPT_SET_INT(0, "exact-match", &max_candidates,
 569                             N_("only output exact matches"), 0),
 570                 OPT_INTEGER(0, "candidates", &max_candidates,
 571                             N_("consider <n> most recent tags (default: 10)")),
 572                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
 573                            N_("only consider tags matching <pattern>")),
 574                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
 575                            N_("do not consider tags matching <pattern>")),
 576                 OPT_BOOL(0, "always",        &always,
 577                         N_("show abbreviated commit object as fallback")),
 578                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
 579                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
 580                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
 581                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
 582                         N_("append <mark> on broken working tree (default: \"-broken\")"),
 583                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
 584                 OPT_END(),
 585         };
 586
 587         git_config(git_default_config, NULL);
 588         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
 589         if (abbrev < 0)
 590                 abbrev = DEFAULT_ABBREV;
 591
 592         if (max_candidates < 0)
 593                 max_candidates = 0;
 594         else if (max_candidates > MAX_TAGS)
 595                 max_candidates = MAX_TAGS;
 596
 597         save_commit_buffer = 0;
 598
 599         if (longformat && abbrev == 0)
 600                 die(_("options '%s' and '%s' cannot be used together"), "--long", "--abbrev=0");
 601
 602         if (contains) {
 603                 struct string_list_item *item;
 604                 struct strvec args;
 605
 606                 strvec_init(&args);
 607                 strvec_pushl(&args, "name-rev",
 608                              "--peel-tag", "--name-only", "--no-undefined",
 609                              NULL);
 610                 if (always)
 611                         strvec_push(&args, "--always");
 612                 if (!all) {
 613                         strvec_push(&args, "--tags");
 614                         for_each_string_list_item(item, &patterns)
 615                                 strvec_pushf(&args, "--refs=refs/tags/%s", item->string);
 616                         for_each_string_list_item(item, &exclude_patterns)
 617                                 strvec_pushf(&args, "--exclude=refs/tags/%s", item->string);
 618                 }
 619                 if (argc)
 620                         strvec_pushv(&args, argv);
 621                 else
 622                         strvec_push(&args, "HEAD");
 623                 return cmd_name_rev(args.nr, args.v, prefix);
 624         }
 625
 626         hashmap_init(&names, commit_name_neq, NULL, 0);
 627         for_each_rawref(get_name, NULL);
 628         if (!hashmap_get_size(&names) && !always)
 629                 die(_("No names found, cannot describe anything."));
 630
 631         if (argc == 0) {
 632                 if (broken) {
 633                         struct child_process cp = CHILD_PROCESS_INIT;
 634                         strvec_pushv(&cp.args, diff_index_args);
 635                         cp.git_cmd = 1;
 636                         cp.no_stdin = 1;
 637                         cp.no_stdout = 1;
 638
 639                         if (!dirty)
 640                                 dirty = "-dirty";
 641
 642                         switch (run_command(&cp)) {
 643                         case 0:
 644                                 suffix = NULL;
 645                                 break;
 646                         case 1:
 647                                 suffix = dirty;
 648                                 break;
 649                         default:
 650                                 /* diff-index aborted abnormally */
 651                                 suffix = broken;
 652                         }
 653                 } else if (dirty) {
 654                         struct lock_file index_lock = LOCK_INIT;
 655                         struct rev_info revs;
 656                         struct strvec args = STRVEC_INIT;
 657                         int fd, result;
 658
 659                         setup_work_tree();
 660                         repo_read_index(the_repository);
 661                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
 662                                       NULL, NULL, NULL);
 663                         fd = repo_hold_locked_index(the_repository,
 664                                                     &index_lock, 0);
 665                         if (0 <= fd)
 666                                 repo_update_index_if_able(the_repository, &index_lock);
 667
 668                         repo_init_revisions(the_repository, &revs, prefix);
 669                         strvec_pushv(&args, diff_index_args);
 670                         if (setup_revisions(args.nr, args.v, &revs, NULL) != 1)
 671                                 BUG("malformed internal diff-index command line");
 672                         result = run_diff_index(&revs, 0);
 673
 674                         if (!diff_result_code(&revs.diffopt, result))
 675                                 suffix = NULL;
 676                         else
 677                                 suffix = dirty;
 678                         release_revisions(&revs);
 679                 }
 680                 describe("HEAD", 1);
 681         } else if (dirty) {
 682                 die(_("option '%s' and commit-ishes cannot be used together"), "--dirty");
 683         } else if (broken) {
 684                 die(_("option '%s' and commit-ishes cannot be used together"), "--broken");
 685         } else {
 686                 while (argc-- > 0)
 687                         describe(*argv++, argc == 0);
 688         }
 689         return 0;
 690 }