diff-lib.c

   1 /*
   2  * Copyright (C) 2005 Junio C Hamano
   3  */
   4 #include "cache.h"
   5 #include "quote.h"
   6 #include "commit.h"
   7 #include "diff.h"
   8 #include "diffcore.h"
   9 #include "gettext.h"
  10 #include "hex.h"
  11 #include "object-name.h"
  12 #include "revision.h"
  13 #include "cache-tree.h"
  14 #include "unpack-trees.h"
  15 #include "refs.h"
  16 #include "submodule.h"
  17 #include "trace.h"
  18 #include "dir.h"
  19 #include "fsmonitor.h"
  20 #include "commit-reach.h"
  21
  22 /*
  23  * diff-files
  24  */
  25
  26 /*
  27  * Has the work tree entity been removed?
  28  *
  29  * Return 1 if it was removed from the work tree, 0 if an entity to be
  30  * compared with the cache entry ce still exists (the latter includes
  31  * the case where a directory that is not a submodule repository
  32  * exists for ce that is a submodule -- it is a submodule that is not
  33  * checked out).  Return negative for an error.
  34  */
  35 static int check_removed(const struct index_state *istate, const struct cache_entry *ce, struct stat *st)
  36 {
  37         assert(is_fsmonitor_refreshed(istate));
  38         if (!(ce->ce_flags & CE_FSMONITOR_VALID) && lstat(ce->name, st) < 0) {
  39                 if (!is_missing_file_error(errno))
  40                         return -1;
  41                 return 1;
  42         }
  43         if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
  44                 return 1;
  45         if (S_ISDIR(st->st_mode)) {
  46                 struct object_id sub;
  47
  48                 /*
  49                  * If ce is already a gitlink, we can have a plain
  50                  * directory (i.e. the submodule is not checked out),
  51                  * or a checked out submodule.  Either case this is not
  52                  * a case where something was removed from the work tree,
  53                  * so we will return 0.
  54                  *
  55                  * Otherwise, if the directory is not a submodule
  56                  * repository, that means ce which was a blob turned into
  57                  * a directory --- the blob was removed!
  58                  */
  59                 if (!S_ISGITLINK(ce->ce_mode) &&
  60                     resolve_gitlink_ref(ce->name, "HEAD", &sub))
  61                         return 1;
  62         }
  63         return 0;
  64 }
  65
  66 /*
  67  * Has a file changed or has a submodule new commits or a dirty work tree?
  68  *
  69  * Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
  70  * option is set, the caller does not only want to know if a submodule is
  71  * modified at all but wants to know all the conditions that are met (new
  72  * commits, untracked content and/or modified content).
  73  */
  74 static int match_stat_with_submodule(struct diff_options *diffopt,
  75                                      const struct cache_entry *ce,
  76                                      struct stat *st, unsigned ce_option,
  77                                      unsigned *dirty_submodule)
  78 {
  79         int changed = ie_match_stat(diffopt->repo->index, ce, st, ce_option);
  80         if (S_ISGITLINK(ce->ce_mode)) {
  81                 struct diff_flags orig_flags = diffopt->flags;
  82                 if (!diffopt->flags.override_submodule_config)
  83                         set_diffopt_flags_from_submodule_config(diffopt, ce->name);
  84                 if (diffopt->flags.ignore_submodules)
  85                         changed = 0;
  86                 else if (!diffopt->flags.ignore_dirty_submodules &&
  87                          (!changed || diffopt->flags.dirty_submodules))
  88                         *dirty_submodule = is_submodule_modified(ce->name,
  89                                                                  diffopt->flags.ignore_untracked_in_submodules);
  90                 diffopt->flags = orig_flags;
  91         }
  92         return changed;
  93 }
  94
  95 int run_diff_files(struct rev_info *revs, unsigned int option)
  96 {
  97         int entries, i;
  98         int diff_unmerged_stage = revs->max_count;
  99         unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
 100                               ? CE_MATCH_RACY_IS_DIRTY : 0);
 101         uint64_t start = getnanotime();
 102         struct index_state *istate = revs->diffopt.repo->index;
 103
 104         diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
 105
 106         refresh_fsmonitor(istate);
 107
 108         if (diff_unmerged_stage < 0)
 109                 diff_unmerged_stage = 2;
 110         entries = istate->cache_nr;
 111         for (i = 0; i < entries; i++) {
 112                 unsigned int oldmode, newmode;
 113                 struct cache_entry *ce = istate->cache[i];
 114                 int changed;
 115                 unsigned dirty_submodule = 0;
 116                 const struct object_id *old_oid, *new_oid;
 117
 118                 if (diff_can_quit_early(&revs->diffopt))
 119                         break;
 120
 121                 if (!ce_path_match(istate, ce, &revs->prune_data, NULL))
 122                         continue;
 123
 124                 if (revs->diffopt.prefix &&
 125                     strncmp(ce->name, revs->diffopt.prefix, revs->diffopt.prefix_length))
 126                         continue;
 127
 128                 if (ce_stage(ce)) {
 129                         struct combine_diff_path *dpath;
 130                         struct diff_filepair *pair;
 131                         unsigned int wt_mode = 0;
 132                         int num_compare_stages = 0;
 133                         size_t path_len;
 134                         struct stat st;
 135
 136                         path_len = ce_namelen(ce);
 137
 138                         dpath = xmalloc(combine_diff_path_size(5, path_len));
 139                         dpath->path = (char *) &(dpath->parent[5]);
 140
 141                         dpath->next = NULL;
 142                         memcpy(dpath->path, ce->name, path_len);
 143                         dpath->path[path_len] = '\0';
 144                         oidclr(&dpath->oid);
 145                         memset(&(dpath->parent[0]), 0,
 146                                sizeof(struct combine_diff_parent)*5);
 147
 148                         changed = check_removed(istate, ce, &st);
 149                         if (!changed)
 150                                 wt_mode = ce_mode_from_stat(ce, st.st_mode);
 151                         else {
 152                                 if (changed < 0) {
 153                                         perror(ce->name);
 154                                         continue;
 155                                 }
 156                                 wt_mode = 0;
 157                         }
 158                         dpath->mode = wt_mode;
 159
 160                         while (i < entries) {
 161                                 struct cache_entry *nce = istate->cache[i];
 162                                 int stage;
 163
 164                                 if (strcmp(ce->name, nce->name))
 165                                         break;
 166
 167                                 /* Stage #2 (ours) is the first parent,
 168                                  * stage #3 (theirs) is the second.
 169                                  */
 170                                 stage = ce_stage(nce);
 171                                 if (2 <= stage) {
 172                                         int mode = nce->ce_mode;
 173                                         num_compare_stages++;
 174                                         oidcpy(&dpath->parent[stage - 2].oid,
 175                                                &nce->oid);
 176                                         dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
 177                                         dpath->parent[stage-2].status =
 178                                                 DIFF_STATUS_MODIFIED;
 179                                 }
 180
 181                                 /* diff against the proper unmerged stage */
 182                                 if (stage == diff_unmerged_stage)
 183                                         ce = nce;
 184                                 i++;
 185                         }
 186                         /*
 187                          * Compensate for loop update
 188                          */
 189                         i--;
 190
 191                         if (revs->combine_merges && num_compare_stages == 2) {
 192                                 show_combined_diff(dpath, 2, revs);
 193                                 free(dpath);
 194                                 continue;
 195                         }
 196                         FREE_AND_NULL(dpath);
 197
 198                         /*
 199                          * Show the diff for the 'ce' if we found the one
 200                          * from the desired stage.
 201                          */
 202                         pair = diff_unmerge(&revs->diffopt, ce->name);
 203                         if (wt_mode)
 204                                 pair->two->mode = wt_mode;
 205                         if (ce_stage(ce) != diff_unmerged_stage)
 206                                 continue;
 207                 }
 208
 209                 if (ce_uptodate(ce) || ce_skip_worktree(ce))
 210                         continue;
 211
 212                 /*
 213                  * When CE_VALID is set (via "update-index --assume-unchanged"
 214                  * or via adding paths while core.ignorestat is set to true),
 215                  * the user has promised that the working tree file for that
 216                  * path will not be modified.  When CE_FSMONITOR_VALID is true,
 217                  * the fsmonitor knows that the path hasn't been modified since
 218                  * we refreshed the cached stat information.  In either case,
 219                  * we do not have to stat to see if the path has been removed
 220                  * or modified.
 221                  */
 222                 if (ce->ce_flags & (CE_VALID | CE_FSMONITOR_VALID)) {
 223                         changed = 0;
 224                         newmode = ce->ce_mode;
 225                 } else {
 226                         struct stat st;
 227
 228                         changed = check_removed(istate, ce, &st);
 229                         if (changed) {
 230                                 if (changed < 0) {
 231                                         perror(ce->name);
 232                                         continue;
 233                                 }
 234                                 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
 235                                                &ce->oid,
 236                                                !is_null_oid(&ce->oid),
 237                                                ce->name, 0);
 238                                 continue;
 239                         } else if (revs->diffopt.ita_invisible_in_index &&
 240                                    ce_intent_to_add(ce)) {
 241                                 newmode = ce_mode_from_stat(ce, st.st_mode);
 242                                 diff_addremove(&revs->diffopt, '+', newmode,
 243                                                null_oid(), 0, ce->name, 0);
 244                                 continue;
 245                         }
 246
 247                         changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
 248                                                             ce_option, &dirty_submodule);
 249                         newmode = ce_mode_from_stat(ce, st.st_mode);
 250                 }
 251
 252                 if (!changed && !dirty_submodule) {
 253                         ce_mark_uptodate(ce);
 254                         mark_fsmonitor_valid(istate, ce);
 255                         if (!revs->diffopt.flags.find_copies_harder)
 256                                 continue;
 257                 }
 258                 oldmode = ce->ce_mode;
 259                 old_oid = &ce->oid;
 260                 new_oid = changed ? null_oid() : &ce->oid;
 261                 diff_change(&revs->diffopt, oldmode, newmode,
 262                             old_oid, new_oid,
 263                             !is_null_oid(old_oid),
 264                             !is_null_oid(new_oid),
 265                             ce->name, 0, dirty_submodule);
 266
 267         }
 268         diffcore_std(&revs->diffopt);
 269         diff_flush(&revs->diffopt);
 270         trace_performance_since(start, "diff-files");
 271         return 0;
 272 }
 273
 274 /*
 275  * diff-index
 276  */
 277
 278 /* A file entry went away or appeared */
 279 static void diff_index_show_file(struct rev_info *revs,
 280                                  const char *prefix,
 281                                  const struct cache_entry *ce,
 282                                  const struct object_id *oid, int oid_valid,
 283                                  unsigned int mode,
 284                                  unsigned dirty_submodule)
 285 {
 286         diff_addremove(&revs->diffopt, prefix[0], mode,
 287                        oid, oid_valid, ce->name, dirty_submodule);
 288 }
 289
 290 static int get_stat_data(const struct index_state *istate,
 291                          const struct cache_entry *ce,
 292                          const struct object_id **oidp,
 293                          unsigned int *modep,
 294                          int cached, int match_missing,
 295                          unsigned *dirty_submodule, struct diff_options *diffopt)
 296 {
 297         const struct object_id *oid = &ce->oid;
 298         unsigned int mode = ce->ce_mode;
 299
 300         if (!cached && !ce_uptodate(ce)) {
 301                 int changed;
 302                 struct stat st;
 303                 changed = check_removed(istate, ce, &st);
 304                 if (changed < 0)
 305                         return -1;
 306                 else if (changed) {
 307                         if (match_missing) {
 308                                 *oidp = oid;
 309                                 *modep = mode;
 310                                 return 0;
 311                         }
 312                         return -1;
 313                 }
 314                 changed = match_stat_with_submodule(diffopt, ce, &st,
 315                                                     0, dirty_submodule);
 316                 if (changed) {
 317                         mode = ce_mode_from_stat(ce, st.st_mode);
 318                         oid = null_oid();
 319                 }
 320         }
 321
 322         *oidp = oid;
 323         *modep = mode;
 324         return 0;
 325 }
 326
 327 static void show_new_file(struct rev_info *revs,
 328                           const struct cache_entry *new_file,
 329                           int cached, int match_missing)
 330 {
 331         const struct object_id *oid;
 332         unsigned int mode;
 333         unsigned dirty_submodule = 0;
 334         struct index_state *istate = revs->diffopt.repo->index;
 335
 336         if (new_file && S_ISSPARSEDIR(new_file->ce_mode)) {
 337                 diff_tree_oid(NULL, &new_file->oid, new_file->name, &revs->diffopt);
 338                 return;
 339         }
 340
 341         /*
 342          * New file in the index: it might actually be different in
 343          * the working tree.
 344          */
 345         if (get_stat_data(istate, new_file, &oid, &mode, cached, match_missing,
 346             &dirty_submodule, &revs->diffopt) < 0)
 347                 return;
 348
 349         diff_index_show_file(revs, "+", new_file, oid, !is_null_oid(oid), mode, dirty_submodule);
 350 }
 351
 352 static int show_modified(struct rev_info *revs,
 353                          const struct cache_entry *old_entry,
 354                          const struct cache_entry *new_entry,
 355                          int report_missing,
 356                          int cached, int match_missing)
 357 {
 358         unsigned int mode, oldmode;
 359         const struct object_id *oid;
 360         unsigned dirty_submodule = 0;
 361         struct index_state *istate = revs->diffopt.repo->index;
 362
 363         assert(S_ISSPARSEDIR(old_entry->ce_mode) ==
 364                S_ISSPARSEDIR(new_entry->ce_mode));
 365
 366         /*
 367          * If both are sparse directory entries, then expand the
 368          * modifications to the file level. If only one was a sparse
 369          * directory, then they appear as an add and delete instead of
 370          * a modification.
 371          */
 372         if (S_ISSPARSEDIR(new_entry->ce_mode)) {
 373                 diff_tree_oid(&old_entry->oid, &new_entry->oid, new_entry->name, &revs->diffopt);
 374                 return 0;
 375         }
 376
 377         if (get_stat_data(istate, new_entry, &oid, &mode, cached, match_missing,
 378                           &dirty_submodule, &revs->diffopt) < 0) {
 379                 if (report_missing)
 380                         diff_index_show_file(revs, "-", old_entry,
 381                                              &old_entry->oid, 1, old_entry->ce_mode,
 382                                              0);
 383                 return -1;
 384         }
 385
 386         if (revs->combine_merges && !cached &&
 387             (!oideq(oid, &old_entry->oid) || !oideq(&old_entry->oid, &new_entry->oid))) {
 388                 struct combine_diff_path *p;
 389                 int pathlen = ce_namelen(new_entry);
 390
 391                 p = xmalloc(combine_diff_path_size(2, pathlen));
 392                 p->path = (char *) &p->parent[2];
 393                 p->next = NULL;
 394                 memcpy(p->path, new_entry->name, pathlen);
 395                 p->path[pathlen] = 0;
 396                 p->mode = mode;
 397                 oidclr(&p->oid);
 398                 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 399                 p->parent[0].status = DIFF_STATUS_MODIFIED;
 400                 p->parent[0].mode = new_entry->ce_mode;
 401                 oidcpy(&p->parent[0].oid, &new_entry->oid);
 402                 p->parent[1].status = DIFF_STATUS_MODIFIED;
 403                 p->parent[1].mode = old_entry->ce_mode;
 404                 oidcpy(&p->parent[1].oid, &old_entry->oid);
 405                 show_combined_diff(p, 2, revs);
 406                 free(p);
 407                 return 0;
 408         }
 409
 410         oldmode = old_entry->ce_mode;
 411         if (mode == oldmode && oideq(oid, &old_entry->oid) && !dirty_submodule &&
 412             !revs->diffopt.flags.find_copies_harder)
 413                 return 0;
 414
 415         diff_change(&revs->diffopt, oldmode, mode,
 416                     &old_entry->oid, oid, 1, !is_null_oid(oid),
 417                     old_entry->name, 0, dirty_submodule);
 418         return 0;
 419 }
 420
 421 /*
 422  * This gets a mix of an existing index and a tree, one pathname entry
 423  * at a time. The index entry may be a single stage-0 one, but it could
 424  * also be multiple unmerged entries (in which case idx_pos/idx_nr will
 425  * give you the position and number of entries in the index).
 426  */
 427 static void do_oneway_diff(struct unpack_trees_options *o,
 428                            const struct cache_entry *idx,
 429                            const struct cache_entry *tree)
 430 {
 431         struct rev_info *revs = o->unpack_data;
 432         int match_missing, cached;
 433
 434         /*
 435          * i-t-a entries do not actually exist in the index (if we're
 436          * looking at its content)
 437          */
 438         if (o->index_only &&
 439             revs->diffopt.ita_invisible_in_index &&
 440             idx && ce_intent_to_add(idx)) {
 441                 idx = NULL;
 442                 if (!tree)
 443                         return; /* nothing to diff.. */
 444         }
 445
 446         /* if the entry is not checked out, don't examine work tree */
 447         cached = o->index_only ||
 448                 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
 449
 450         match_missing = revs->match_missing;
 451
 452         if (cached && idx && ce_stage(idx)) {
 453                 struct diff_filepair *pair;
 454                 pair = diff_unmerge(&revs->diffopt, idx->name);
 455                 if (tree)
 456                         fill_filespec(pair->one, &tree->oid, 1,
 457                                       tree->ce_mode);
 458                 return;
 459         }
 460
 461         /*
 462          * Something added to the tree?
 463          */
 464         if (!tree) {
 465                 show_new_file(revs, idx, cached, match_missing);
 466                 return;
 467         }
 468
 469         /*
 470          * Something removed from the tree?
 471          */
 472         if (!idx) {
 473                 if (S_ISSPARSEDIR(tree->ce_mode)) {
 474                         diff_tree_oid(&tree->oid, NULL, tree->name, &revs->diffopt);
 475                         return;
 476                 }
 477
 478                 diff_index_show_file(revs, "-", tree, &tree->oid, 1,
 479                                      tree->ce_mode, 0);
 480                 return;
 481         }
 482
 483         /* Show difference between old and new */
 484         show_modified(revs, tree, idx, 1, cached, match_missing);
 485 }
 486
 487 /*
 488  * The unpack_trees() interface is designed for merging, so
 489  * the different source entries are designed primarily for
 490  * the source trees, with the old index being really mainly
 491  * used for being replaced by the result.
 492  *
 493  * For diffing, the index is more important, and we only have a
 494  * single tree.
 495  *
 496  * We're supposed to advance o->pos to skip what we have already processed.
 497  *
 498  * This wrapper makes it all more readable, and takes care of all
 499  * the fairly complex unpack_trees() semantic requirements, including
 500  * the skipping, the path matching, the type conflict cases etc.
 501  */
 502 static int oneway_diff(const struct cache_entry * const *src,
 503                        struct unpack_trees_options *o)
 504 {
 505         const struct cache_entry *idx = src[0];
 506         const struct cache_entry *tree = src[1];
 507         struct rev_info *revs = o->unpack_data;
 508
 509         /*
 510          * Unpack-trees generates a DF/conflict entry if
 511          * there was a directory in the index and a tree
 512          * in the tree. From a diff standpoint, that's a
 513          * delete of the tree and a create of the file.
 514          */
 515         if (tree == o->df_conflict_entry)
 516                 tree = NULL;
 517
 518         if (ce_path_match(revs->diffopt.repo->index,
 519                           idx ? idx : tree,
 520                           &revs->prune_data, NULL)) {
 521                 do_oneway_diff(o, idx, tree);
 522                 if (diff_can_quit_early(&revs->diffopt)) {
 523                         o->exiting_early = 1;
 524                         return -1;
 525                 }
 526         }
 527
 528         return 0;
 529 }
 530
 531 static int diff_cache(struct rev_info *revs,
 532                       const struct object_id *tree_oid,
 533                       const char *tree_name,
 534                       int cached)
 535 {
 536         struct tree *tree;
 537         struct tree_desc t;
 538         struct unpack_trees_options opts;
 539
 540         tree = parse_tree_indirect(tree_oid);
 541         if (!tree)
 542                 return error("bad tree object %s",
 543                              tree_name ? tree_name : oid_to_hex(tree_oid));
 544         memset(&opts, 0, sizeof(opts));
 545         opts.head_idx = 1;
 546         opts.index_only = cached;
 547         opts.diff_index_cached = (cached &&
 548                                   !revs->diffopt.flags.find_copies_harder);
 549         opts.merge = 1;
 550         opts.fn = oneway_diff;
 551         opts.unpack_data = revs;
 552         opts.src_index = revs->diffopt.repo->index;
 553         opts.dst_index = NULL;
 554         opts.pathspec = &revs->diffopt.pathspec;
 555         opts.pathspec->recursive = 1;
 556
 557         init_tree_desc(&t, tree->buffer, tree->size);
 558         return unpack_trees(1, &t, &opts);
 559 }
 560
 561 void diff_get_merge_base(const struct rev_info *revs, struct object_id *mb)
 562 {
 563         int i;
 564         struct commit *mb_child[2] = {0};
 565         struct commit_list *merge_bases;
 566
 567         for (i = 0; i < revs->pending.nr; i++) {
 568                 struct object *obj = revs->pending.objects[i].item;
 569                 if (obj->flags)
 570                         die(_("--merge-base does not work with ranges"));
 571                 if (obj->type != OBJ_COMMIT)
 572                         die(_("--merge-base only works with commits"));
 573         }
 574
 575         /*
 576          * This check must go after the for loop above because A...B
 577          * ranges produce three pending commits, resulting in a
 578          * misleading error message.
 579          */
 580         if (revs->pending.nr < 1 || revs->pending.nr > 2)
 581                 BUG("unexpected revs->pending.nr: %d", revs->pending.nr);
 582
 583         for (i = 0; i < revs->pending.nr; i++)
 584                 mb_child[i] = lookup_commit_reference(the_repository, &revs->pending.objects[i].item->oid);
 585         if (revs->pending.nr == 1) {
 586                 struct object_id oid;
 587
 588                 if (repo_get_oid(the_repository, "HEAD", &oid))
 589                         die(_("unable to get HEAD"));
 590
 591                 mb_child[1] = lookup_commit_reference(the_repository, &oid);
 592         }
 593
 594         merge_bases = repo_get_merge_bases(the_repository, mb_child[0], mb_child[1]);
 595         if (!merge_bases)
 596                 die(_("no merge base found"));
 597         if (merge_bases->next)
 598                 die(_("multiple merge bases found"));
 599
 600         oidcpy(mb, &merge_bases->item->object.oid);
 601
 602         free_commit_list(merge_bases);
 603 }
 604
 605 int run_diff_index(struct rev_info *revs, unsigned int option)
 606 {
 607         struct object_array_entry *ent;
 608         int cached = !!(option & DIFF_INDEX_CACHED);
 609         int merge_base = !!(option & DIFF_INDEX_MERGE_BASE);
 610         struct object_id oid;
 611         const char *name;
 612         char merge_base_hex[GIT_MAX_HEXSZ + 1];
 613         struct index_state *istate = revs->diffopt.repo->index;
 614
 615         if (revs->pending.nr != 1)
 616                 BUG("run_diff_index must be passed exactly one tree");
 617
 618         trace_performance_enter();
 619         ent = revs->pending.objects;
 620
 621         refresh_fsmonitor(istate);
 622
 623         if (merge_base) {
 624                 diff_get_merge_base(revs, &oid);
 625                 name = oid_to_hex_r(merge_base_hex, &oid);
 626         } else {
 627                 oidcpy(&oid, &ent->item->oid);
 628                 name = ent->name;
 629         }
 630
 631         if (diff_cache(revs, &oid, name, cached))
 632                 exit(128);
 633
 634         diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
 635         diffcore_fix_diff_index();
 636         diffcore_std(&revs->diffopt);
 637         diff_flush(&revs->diffopt);
 638         trace_performance_leave("diff-index");
 639         return 0;
 640 }
 641
 642 int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
 643 {
 644         struct rev_info revs;
 645
 646         repo_init_revisions(opt->repo, &revs, NULL);
 647         copy_pathspec(&revs.prune_data, &opt->pathspec);
 648         diff_setup_done(&revs.diffopt);
 649         revs.diffopt = *opt;
 650
 651         if (diff_cache(&revs, tree_oid, NULL, 1))
 652                 exit(128);
 653         release_revisions(&revs);
 654         return 0;
 655 }
 656
 657 int index_differs_from(struct repository *r,
 658                        const char *def, const struct diff_flags *flags,
 659                        int ita_invisible_in_index)
 660 {
 661         struct rev_info rev;
 662         struct setup_revision_opt opt;
 663         unsigned has_changes;
 664
 665         repo_init_revisions(r, &rev, NULL);
 666         memset(&opt, 0, sizeof(opt));
 667         opt.def = def;
 668         setup_revisions(0, NULL, &rev, &opt);
 669         rev.diffopt.flags.quick = 1;
 670         rev.diffopt.flags.exit_with_status = 1;
 671         if (flags)
 672                 diff_flags_or(&rev.diffopt.flags, flags);
 673         rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
 674         run_diff_index(&rev, 1);
 675         has_changes = rev.diffopt.flags.has_changes;
 676         release_revisions(&rev);
 677         return (has_changes != 0);
 678 }
 679
 680 static struct strbuf *idiff_prefix_cb(struct diff_options *opt UNUSED, void *data)
 681 {
 682         return data;
 683 }
 684
 685 void show_interdiff(const struct object_id *oid1, const struct object_id *oid2,
 686                     int indent, struct diff_options *diffopt)
 687 {
 688         struct diff_options opts;
 689         struct strbuf prefix = STRBUF_INIT;
 690
 691         memcpy(&opts, diffopt, sizeof(opts));
 692         opts.output_format = DIFF_FORMAT_PATCH;
 693         opts.output_prefix = idiff_prefix_cb;
 694         strbuf_addchars(&prefix, ' ', indent);
 695         opts.output_prefix_data = &prefix;
 696         diff_setup_done(&opts);
 697
 698         diff_tree_oid(oid1, oid2, "", &opts);
 699         diffcore_std(&opts);
 700         diff_flush(&opts);
 701
 702         strbuf_release(&prefix);
 703 }