diff-lib.con commit Merge branch 'dl/rebase-i-keep-base' (640f9cd)
   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 "revision.h"
  10#include "cache-tree.h"
  11#include "unpack-trees.h"
  12#include "refs.h"
  13#include "submodule.h"
  14#include "dir.h"
  15#include "fsmonitor.h"
  16
  17/*
  18 * diff-files
  19 */
  20
  21/*
  22 * Has the work tree entity been removed?
  23 *
  24 * Return 1 if it was removed from the work tree, 0 if an entity to be
  25 * compared with the cache entry ce still exists (the latter includes
  26 * the case where a directory that is not a submodule repository
  27 * exists for ce that is a submodule -- it is a submodule that is not
  28 * checked out).  Return negative for an error.
  29 */
  30static int check_removed(const struct cache_entry *ce, struct stat *st)
  31{
  32        if (lstat(ce->name, st) < 0) {
  33                if (!is_missing_file_error(errno))
  34                        return -1;
  35                return 1;
  36        }
  37        if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
  38                return 1;
  39        if (S_ISDIR(st->st_mode)) {
  40                struct object_id sub;
  41
  42                /*
  43                 * If ce is already a gitlink, we can have a plain
  44                 * directory (i.e. the submodule is not checked out),
  45                 * or a checked out submodule.  Either case this is not
  46                 * a case where something was removed from the work tree,
  47                 * so we will return 0.
  48                 *
  49                 * Otherwise, if the directory is not a submodule
  50                 * repository, that means ce which was a blob turned into
  51                 * a directory --- the blob was removed!
  52                 */
  53                if (!S_ISGITLINK(ce->ce_mode) &&
  54                    resolve_gitlink_ref(ce->name, "HEAD", &sub))
  55                        return 1;
  56        }
  57        return 0;
  58}
  59
  60/*
  61 * Has a file changed or has a submodule new commits or a dirty work tree?
  62 *
  63 * Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
  64 * option is set, the caller does not only want to know if a submodule is
  65 * modified at all but wants to know all the conditions that are met (new
  66 * commits, untracked content and/or modified content).
  67 */
  68static int match_stat_with_submodule(struct diff_options *diffopt,
  69                                     const struct cache_entry *ce,
  70                                     struct stat *st, unsigned ce_option,
  71                                     unsigned *dirty_submodule)
  72{
  73        int changed = ie_match_stat(diffopt->repo->index, ce, st, ce_option);
  74        if (S_ISGITLINK(ce->ce_mode)) {
  75                struct diff_flags orig_flags = diffopt->flags;
  76                if (!diffopt->flags.override_submodule_config)
  77                        set_diffopt_flags_from_submodule_config(diffopt, ce->name);
  78                if (diffopt->flags.ignore_submodules)
  79                        changed = 0;
  80                else if (!diffopt->flags.ignore_dirty_submodules &&
  81                         (!changed || diffopt->flags.dirty_submodules))
  82                        *dirty_submodule = is_submodule_modified(ce->name,
  83                                                                 diffopt->flags.ignore_untracked_in_submodules);
  84                diffopt->flags = orig_flags;
  85        }
  86        return changed;
  87}
  88
  89int run_diff_files(struct rev_info *revs, unsigned int option)
  90{
  91        int entries, i;
  92        int diff_unmerged_stage = revs->max_count;
  93        unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
  94                              ? CE_MATCH_RACY_IS_DIRTY : 0);
  95        uint64_t start = getnanotime();
  96        struct index_state *istate = revs->diffopt.repo->index;
  97
  98        diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
  99
 100        if (diff_unmerged_stage < 0)
 101                diff_unmerged_stage = 2;
 102        entries = istate->cache_nr;
 103        for (i = 0; i < entries; i++) {
 104                unsigned int oldmode, newmode;
 105                struct cache_entry *ce = istate->cache[i];
 106                int changed;
 107                unsigned dirty_submodule = 0;
 108                const struct object_id *old_oid, *new_oid;
 109
 110                if (diff_can_quit_early(&revs->diffopt))
 111                        break;
 112
 113                if (!ce_path_match(istate, ce, &revs->prune_data, NULL))
 114                        continue;
 115
 116                if (ce_stage(ce)) {
 117                        struct combine_diff_path *dpath;
 118                        struct diff_filepair *pair;
 119                        unsigned int wt_mode = 0;
 120                        int num_compare_stages = 0;
 121                        size_t path_len;
 122                        struct stat st;
 123
 124                        path_len = ce_namelen(ce);
 125
 126                        dpath = xmalloc(combine_diff_path_size(5, path_len));
 127                        dpath->path = (char *) &(dpath->parent[5]);
 128
 129                        dpath->next = NULL;
 130                        memcpy(dpath->path, ce->name, path_len);
 131                        dpath->path[path_len] = '\0';
 132                        oidclr(&dpath->oid);
 133                        memset(&(dpath->parent[0]), 0,
 134                               sizeof(struct combine_diff_parent)*5);
 135
 136                        changed = check_removed(ce, &st);
 137                        if (!changed)
 138                                wt_mode = ce_mode_from_stat(ce, st.st_mode);
 139                        else {
 140                                if (changed < 0) {
 141                                        perror(ce->name);
 142                                        continue;
 143                                }
 144                                wt_mode = 0;
 145                        }
 146                        dpath->mode = wt_mode;
 147
 148                        while (i < entries) {
 149                                struct cache_entry *nce = istate->cache[i];
 150                                int stage;
 151
 152                                if (strcmp(ce->name, nce->name))
 153                                        break;
 154
 155                                /* Stage #2 (ours) is the first parent,
 156                                 * stage #3 (theirs) is the second.
 157                                 */
 158                                stage = ce_stage(nce);
 159                                if (2 <= stage) {
 160                                        int mode = nce->ce_mode;
 161                                        num_compare_stages++;
 162                                        oidcpy(&dpath->parent[stage - 2].oid,
 163                                               &nce->oid);
 164                                        dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
 165                                        dpath->parent[stage-2].status =
 166                                                DIFF_STATUS_MODIFIED;
 167                                }
 168
 169                                /* diff against the proper unmerged stage */
 170                                if (stage == diff_unmerged_stage)
 171                                        ce = nce;
 172                                i++;
 173                        }
 174                        /*
 175                         * Compensate for loop update
 176                         */
 177                        i--;
 178
 179                        if (revs->combine_merges && num_compare_stages == 2) {
 180                                show_combined_diff(dpath, 2,
 181                                                   revs->dense_combined_merges,
 182                                                   revs);
 183                                free(dpath);
 184                                continue;
 185                        }
 186                        FREE_AND_NULL(dpath);
 187
 188                        /*
 189                         * Show the diff for the 'ce' if we found the one
 190                         * from the desired stage.
 191                         */
 192                        pair = diff_unmerge(&revs->diffopt, ce->name);
 193                        if (wt_mode)
 194                                pair->two->mode = wt_mode;
 195                        if (ce_stage(ce) != diff_unmerged_stage)
 196                                continue;
 197                }
 198
 199                if (ce_uptodate(ce) || ce_skip_worktree(ce))
 200                        continue;
 201
 202                /* If CE_VALID is set, don't look at workdir for file removal */
 203                if (ce->ce_flags & CE_VALID) {
 204                        changed = 0;
 205                        newmode = ce->ce_mode;
 206                } else {
 207                        struct stat st;
 208
 209                        changed = check_removed(ce, &st);
 210                        if (changed) {
 211                                if (changed < 0) {
 212                                        perror(ce->name);
 213                                        continue;
 214                                }
 215                                diff_addremove(&revs->diffopt, '-', ce->ce_mode,
 216                                               &ce->oid,
 217                                               !is_null_oid(&ce->oid),
 218                                               ce->name, 0);
 219                                continue;
 220                        } else if (revs->diffopt.ita_invisible_in_index &&
 221                                   ce_intent_to_add(ce)) {
 222                                diff_addremove(&revs->diffopt, '+', ce->ce_mode,
 223                                               the_hash_algo->empty_tree, 0,
 224                                               ce->name, 0);
 225                                continue;
 226                        }
 227
 228                        changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
 229                                                            ce_option, &dirty_submodule);
 230                        newmode = ce_mode_from_stat(ce, st.st_mode);
 231                }
 232
 233                if (!changed && !dirty_submodule) {
 234                        ce_mark_uptodate(ce);
 235                        mark_fsmonitor_valid(istate, ce);
 236                        if (!revs->diffopt.flags.find_copies_harder)
 237                                continue;
 238                }
 239                oldmode = ce->ce_mode;
 240                old_oid = &ce->oid;
 241                new_oid = changed ? &null_oid : &ce->oid;
 242                diff_change(&revs->diffopt, oldmode, newmode,
 243                            old_oid, new_oid,
 244                            !is_null_oid(old_oid),
 245                            !is_null_oid(new_oid),
 246                            ce->name, 0, dirty_submodule);
 247
 248        }
 249        diffcore_std(&revs->diffopt);
 250        diff_flush(&revs->diffopt);
 251        trace_performance_since(start, "diff-files");
 252        return 0;
 253}
 254
 255/*
 256 * diff-index
 257 */
 258
 259/* A file entry went away or appeared */
 260static void diff_index_show_file(struct rev_info *revs,
 261                                 const char *prefix,
 262                                 const struct cache_entry *ce,
 263                                 const struct object_id *oid, int oid_valid,
 264                                 unsigned int mode,
 265                                 unsigned dirty_submodule)
 266{
 267        diff_addremove(&revs->diffopt, prefix[0], mode,
 268                       oid, oid_valid, ce->name, dirty_submodule);
 269}
 270
 271static int get_stat_data(const struct cache_entry *ce,
 272                         const struct object_id **oidp,
 273                         unsigned int *modep,
 274                         int cached, int match_missing,
 275                         unsigned *dirty_submodule, struct diff_options *diffopt)
 276{
 277        const struct object_id *oid = &ce->oid;
 278        unsigned int mode = ce->ce_mode;
 279
 280        if (!cached && !ce_uptodate(ce)) {
 281                int changed;
 282                struct stat st;
 283                changed = check_removed(ce, &st);
 284                if (changed < 0)
 285                        return -1;
 286                else if (changed) {
 287                        if (match_missing) {
 288                                *oidp = oid;
 289                                *modep = mode;
 290                                return 0;
 291                        }
 292                        return -1;
 293                }
 294                changed = match_stat_with_submodule(diffopt, ce, &st,
 295                                                    0, dirty_submodule);
 296                if (changed) {
 297                        mode = ce_mode_from_stat(ce, st.st_mode);
 298                        oid = &null_oid;
 299                }
 300        }
 301
 302        *oidp = oid;
 303        *modep = mode;
 304        return 0;
 305}
 306
 307static void show_new_file(struct rev_info *revs,
 308                          const struct cache_entry *new_file,
 309                          int cached, int match_missing)
 310{
 311        const struct object_id *oid;
 312        unsigned int mode;
 313        unsigned dirty_submodule = 0;
 314
 315        /*
 316         * New file in the index: it might actually be different in
 317         * the working tree.
 318         */
 319        if (get_stat_data(new_file, &oid, &mode, cached, match_missing,
 320            &dirty_submodule, &revs->diffopt) < 0)
 321                return;
 322
 323        diff_index_show_file(revs, "+", new_file, oid, !is_null_oid(oid), mode, dirty_submodule);
 324}
 325
 326static int show_modified(struct rev_info *revs,
 327                         const struct cache_entry *old_entry,
 328                         const struct cache_entry *new_entry,
 329                         int report_missing,
 330                         int cached, int match_missing)
 331{
 332        unsigned int mode, oldmode;
 333        const struct object_id *oid;
 334        unsigned dirty_submodule = 0;
 335
 336        if (get_stat_data(new_entry, &oid, &mode, cached, match_missing,
 337                          &dirty_submodule, &revs->diffopt) < 0) {
 338                if (report_missing)
 339                        diff_index_show_file(revs, "-", old_entry,
 340                                             &old_entry->oid, 1, old_entry->ce_mode,
 341                                             0);
 342                return -1;
 343        }
 344
 345        if (revs->combine_merges && !cached &&
 346            (!oideq(oid, &old_entry->oid) || !oideq(&old_entry->oid, &new_entry->oid))) {
 347                struct combine_diff_path *p;
 348                int pathlen = ce_namelen(new_entry);
 349
 350                p = xmalloc(combine_diff_path_size(2, pathlen));
 351                p->path = (char *) &p->parent[2];
 352                p->next = NULL;
 353                memcpy(p->path, new_entry->name, pathlen);
 354                p->path[pathlen] = 0;
 355                p->mode = mode;
 356                oidclr(&p->oid);
 357                memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 358                p->parent[0].status = DIFF_STATUS_MODIFIED;
 359                p->parent[0].mode = new_entry->ce_mode;
 360                oidcpy(&p->parent[0].oid, &new_entry->oid);
 361                p->parent[1].status = DIFF_STATUS_MODIFIED;
 362                p->parent[1].mode = old_entry->ce_mode;
 363                oidcpy(&p->parent[1].oid, &old_entry->oid);
 364                show_combined_diff(p, 2, revs->dense_combined_merges, revs);
 365                free(p);
 366                return 0;
 367        }
 368
 369        oldmode = old_entry->ce_mode;
 370        if (mode == oldmode && oideq(oid, &old_entry->oid) && !dirty_submodule &&
 371            !revs->diffopt.flags.find_copies_harder)
 372                return 0;
 373
 374        diff_change(&revs->diffopt, oldmode, mode,
 375                    &old_entry->oid, oid, 1, !is_null_oid(oid),
 376                    old_entry->name, 0, dirty_submodule);
 377        return 0;
 378}
 379
 380/*
 381 * This gets a mix of an existing index and a tree, one pathname entry
 382 * at a time. The index entry may be a single stage-0 one, but it could
 383 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
 384 * give you the position and number of entries in the index).
 385 */
 386static void do_oneway_diff(struct unpack_trees_options *o,
 387                           const struct cache_entry *idx,
 388                           const struct cache_entry *tree)
 389{
 390        struct rev_info *revs = o->unpack_data;
 391        int match_missing, cached;
 392
 393        /*
 394         * i-t-a entries do not actually exist in the index (if we're
 395         * looking at its content)
 396         */
 397        if (o->index_only &&
 398            revs->diffopt.ita_invisible_in_index &&
 399            idx && ce_intent_to_add(idx)) {
 400                idx = NULL;
 401                if (!tree)
 402                        return; /* nothing to diff.. */
 403        }
 404
 405        /* if the entry is not checked out, don't examine work tree */
 406        cached = o->index_only ||
 407                (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
 408        /*
 409         * Backward compatibility wart - "diff-index -m" does
 410         * not mean "do not ignore merges", but "match_missing".
 411         *
 412         * But with the revision flag parsing, that's found in
 413         * "!revs->ignore_merges".
 414         */
 415        match_missing = !revs->ignore_merges;
 416
 417        if (cached && idx && ce_stage(idx)) {
 418                struct diff_filepair *pair;
 419                pair = diff_unmerge(&revs->diffopt, idx->name);
 420                if (tree)
 421                        fill_filespec(pair->one, &tree->oid, 1,
 422                                      tree->ce_mode);
 423                return;
 424        }
 425
 426        /*
 427         * Something added to the tree?
 428         */
 429        if (!tree) {
 430                show_new_file(revs, idx, cached, match_missing);
 431                return;
 432        }
 433
 434        /*
 435         * Something removed from the tree?
 436         */
 437        if (!idx) {
 438                diff_index_show_file(revs, "-", tree, &tree->oid, 1,
 439                                     tree->ce_mode, 0);
 440                return;
 441        }
 442
 443        /* Show difference between old and new */
 444        show_modified(revs, tree, idx, 1, cached, match_missing);
 445}
 446
 447/*
 448 * The unpack_trees() interface is designed for merging, so
 449 * the different source entries are designed primarily for
 450 * the source trees, with the old index being really mainly
 451 * used for being replaced by the result.
 452 *
 453 * For diffing, the index is more important, and we only have a
 454 * single tree.
 455 *
 456 * We're supposed to advance o->pos to skip what we have already processed.
 457 *
 458 * This wrapper makes it all more readable, and takes care of all
 459 * the fairly complex unpack_trees() semantic requirements, including
 460 * the skipping, the path matching, the type conflict cases etc.
 461 */
 462static int oneway_diff(const struct cache_entry * const *src,
 463                       struct unpack_trees_options *o)
 464{
 465        const struct cache_entry *idx = src[0];
 466        const struct cache_entry *tree = src[1];
 467        struct rev_info *revs = o->unpack_data;
 468
 469        /*
 470         * Unpack-trees generates a DF/conflict entry if
 471         * there was a directory in the index and a tree
 472         * in the tree. From a diff standpoint, that's a
 473         * delete of the tree and a create of the file.
 474         */
 475        if (tree == o->df_conflict_entry)
 476                tree = NULL;
 477
 478        if (ce_path_match(revs->diffopt.repo->index,
 479                          idx ? idx : tree,
 480                          &revs->prune_data, NULL)) {
 481                do_oneway_diff(o, idx, tree);
 482                if (diff_can_quit_early(&revs->diffopt)) {
 483                        o->exiting_early = 1;
 484                        return -1;
 485                }
 486        }
 487
 488        return 0;
 489}
 490
 491static int diff_cache(struct rev_info *revs,
 492                      const struct object_id *tree_oid,
 493                      const char *tree_name,
 494                      int cached)
 495{
 496        struct tree *tree;
 497        struct tree_desc t;
 498        struct unpack_trees_options opts;
 499
 500        tree = parse_tree_indirect(tree_oid);
 501        if (!tree)
 502                return error("bad tree object %s",
 503                             tree_name ? tree_name : oid_to_hex(tree_oid));
 504        memset(&opts, 0, sizeof(opts));
 505        opts.head_idx = 1;
 506        opts.index_only = cached;
 507        opts.diff_index_cached = (cached &&
 508                                  !revs->diffopt.flags.find_copies_harder);
 509        opts.merge = 1;
 510        opts.fn = oneway_diff;
 511        opts.unpack_data = revs;
 512        opts.src_index = revs->diffopt.repo->index;
 513        opts.dst_index = NULL;
 514        opts.pathspec = &revs->diffopt.pathspec;
 515        opts.pathspec->recursive = 1;
 516
 517        init_tree_desc(&t, tree->buffer, tree->size);
 518        return unpack_trees(1, &t, &opts);
 519}
 520
 521int run_diff_index(struct rev_info *revs, int cached)
 522{
 523        struct object_array_entry *ent;
 524
 525        if (revs->pending.nr != 1)
 526                BUG("run_diff_index must be passed exactly one tree");
 527
 528        trace_performance_enter();
 529        ent = revs->pending.objects;
 530        if (diff_cache(revs, &ent->item->oid, ent->name, cached))
 531                exit(128);
 532
 533        diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
 534        diffcore_fix_diff_index();
 535        diffcore_std(&revs->diffopt);
 536        diff_flush(&revs->diffopt);
 537        trace_performance_leave("diff-index");
 538        return 0;
 539}
 540
 541int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
 542{
 543        struct rev_info revs;
 544
 545        repo_init_revisions(opt->repo, &revs, NULL);
 546        copy_pathspec(&revs.prune_data, &opt->pathspec);
 547        revs.diffopt = *opt;
 548
 549        if (diff_cache(&revs, tree_oid, NULL, 1))
 550                exit(128);
 551        return 0;
 552}
 553
 554int index_differs_from(struct repository *r,
 555                       const char *def, const struct diff_flags *flags,
 556                       int ita_invisible_in_index)
 557{
 558        struct rev_info rev;
 559        struct setup_revision_opt opt;
 560
 561        repo_init_revisions(r, &rev, NULL);
 562        memset(&opt, 0, sizeof(opt));
 563        opt.def = def;
 564        setup_revisions(0, NULL, &rev, &opt);
 565        rev.diffopt.flags.quick = 1;
 566        rev.diffopt.flags.exit_with_status = 1;
 567        if (flags)
 568                diff_flags_or(&rev.diffopt.flags, flags);
 569        rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
 570        run_diff_index(&rev, 1);
 571        object_array_clear(&rev.pending);
 572        return (rev.diffopt.flags.has_changes != 0);
 573}