diff-lib.con commit fsmonitor: simplify determining the git worktree under Windows (1fff303)
   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                unsigned char sub[20];
  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 = ce_match_stat(ce, st, ce_option);
  74        if (S_ISGITLINK(ce->ce_mode)) {
  75                unsigned orig_flags = diffopt->flags;
  76                if (!DIFF_OPT_TST(diffopt, OVERRIDE_SUBMODULE_CONFIG))
  77                        set_diffopt_flags_from_submodule_config(diffopt, ce->name);
  78                if (DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES))
  79                        changed = 0;
  80                else if (!DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)
  81                    && (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES)))
  82                        *dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));
  83                diffopt->flags = orig_flags;
  84        }
  85        return changed;
  86}
  87
  88int run_diff_files(struct rev_info *revs, unsigned int option)
  89{
  90        int entries, i;
  91        int diff_unmerged_stage = revs->max_count;
  92        unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
  93                              ? CE_MATCH_RACY_IS_DIRTY : 0);
  94
  95        diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
  96
  97        if (diff_unmerged_stage < 0)
  98                diff_unmerged_stage = 2;
  99        entries = active_nr;
 100        for (i = 0; i < entries; i++) {
 101                unsigned int oldmode, newmode;
 102                struct cache_entry *ce = active_cache[i];
 103                int changed;
 104                unsigned dirty_submodule = 0;
 105                const struct object_id *old_oid, *new_oid;
 106
 107                if (diff_can_quit_early(&revs->diffopt))
 108                        break;
 109
 110                if (!ce_path_match(ce, &revs->prune_data, NULL))
 111                        continue;
 112
 113                if (ce_stage(ce)) {
 114                        struct combine_diff_path *dpath;
 115                        struct diff_filepair *pair;
 116                        unsigned int wt_mode = 0;
 117                        int num_compare_stages = 0;
 118                        size_t path_len;
 119                        struct stat st;
 120
 121                        path_len = ce_namelen(ce);
 122
 123                        dpath = xmalloc(combine_diff_path_size(5, path_len));
 124                        dpath->path = (char *) &(dpath->parent[5]);
 125
 126                        dpath->next = NULL;
 127                        memcpy(dpath->path, ce->name, path_len);
 128                        dpath->path[path_len] = '\0';
 129                        oidclr(&dpath->oid);
 130                        memset(&(dpath->parent[0]), 0,
 131                               sizeof(struct combine_diff_parent)*5);
 132
 133                        changed = check_removed(ce, &st);
 134                        if (!changed)
 135                                wt_mode = ce_mode_from_stat(ce, st.st_mode);
 136                        else {
 137                                if (changed < 0) {
 138                                        perror(ce->name);
 139                                        continue;
 140                                }
 141                                wt_mode = 0;
 142                        }
 143                        dpath->mode = wt_mode;
 144
 145                        while (i < entries) {
 146                                struct cache_entry *nce = active_cache[i];
 147                                int stage;
 148
 149                                if (strcmp(ce->name, nce->name))
 150                                        break;
 151
 152                                /* Stage #2 (ours) is the first parent,
 153                                 * stage #3 (theirs) is the second.
 154                                 */
 155                                stage = ce_stage(nce);
 156                                if (2 <= stage) {
 157                                        int mode = nce->ce_mode;
 158                                        num_compare_stages++;
 159                                        oidcpy(&dpath->parent[stage - 2].oid,
 160                                               &nce->oid);
 161                                        dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
 162                                        dpath->parent[stage-2].status =
 163                                                DIFF_STATUS_MODIFIED;
 164                                }
 165
 166                                /* diff against the proper unmerged stage */
 167                                if (stage == diff_unmerged_stage)
 168                                        ce = nce;
 169                                i++;
 170                        }
 171                        /*
 172                         * Compensate for loop update
 173                         */
 174                        i--;
 175
 176                        if (revs->combine_merges && num_compare_stages == 2) {
 177                                show_combined_diff(dpath, 2,
 178                                                   revs->dense_combined_merges,
 179                                                   revs);
 180                                free(dpath);
 181                                continue;
 182                        }
 183                        FREE_AND_NULL(dpath);
 184
 185                        /*
 186                         * Show the diff for the 'ce' if we found the one
 187                         * from the desired stage.
 188                         */
 189                        pair = diff_unmerge(&revs->diffopt, ce->name);
 190                        if (wt_mode)
 191                                pair->two->mode = wt_mode;
 192                        if (ce_stage(ce) != diff_unmerged_stage)
 193                                continue;
 194                }
 195
 196                if (ce_uptodate(ce) || ce_skip_worktree(ce))
 197                        continue;
 198
 199                /* If CE_VALID is set, don't look at workdir for file removal */
 200                if (ce->ce_flags & CE_VALID) {
 201                        changed = 0;
 202                        newmode = ce->ce_mode;
 203                } else {
 204                        struct stat st;
 205
 206                        changed = check_removed(ce, &st);
 207                        if (changed) {
 208                                if (changed < 0) {
 209                                        perror(ce->name);
 210                                        continue;
 211                                }
 212                                diff_addremove(&revs->diffopt, '-', ce->ce_mode,
 213                                               &ce->oid,
 214                                               !is_null_oid(&ce->oid),
 215                                               ce->name, 0);
 216                                continue;
 217                        } else if (revs->diffopt.ita_invisible_in_index &&
 218                                   ce_intent_to_add(ce)) {
 219                                diff_addremove(&revs->diffopt, '+', ce->ce_mode,
 220                                               &empty_tree_oid, 0,
 221                                               ce->name, 0);
 222                                continue;
 223                        }
 224
 225                        changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
 226                                                            ce_option, &dirty_submodule);
 227                        newmode = ce_mode_from_stat(ce, st.st_mode);
 228                }
 229
 230                if (!changed && !dirty_submodule) {
 231                        ce_mark_uptodate(ce);
 232                        mark_fsmonitor_valid(ce);
 233                        if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
 234                                continue;
 235                }
 236                oldmode = ce->ce_mode;
 237                old_oid = &ce->oid;
 238                new_oid = changed ? &null_oid : &ce->oid;
 239                diff_change(&revs->diffopt, oldmode, newmode,
 240                            old_oid, new_oid,
 241                            !is_null_oid(old_oid),
 242                            !is_null_oid(new_oid),
 243                            ce->name, 0, dirty_submodule);
 244
 245        }
 246        diffcore_std(&revs->diffopt);
 247        diff_flush(&revs->diffopt);
 248        return 0;
 249}
 250
 251/*
 252 * diff-index
 253 */
 254
 255/* A file entry went away or appeared */
 256static void diff_index_show_file(struct rev_info *revs,
 257                                 const char *prefix,
 258                                 const struct cache_entry *ce,
 259                                 const struct object_id *oid, int oid_valid,
 260                                 unsigned int mode,
 261                                 unsigned dirty_submodule)
 262{
 263        diff_addremove(&revs->diffopt, prefix[0], mode,
 264                       oid, oid_valid, ce->name, dirty_submodule);
 265}
 266
 267static int get_stat_data(const struct cache_entry *ce,
 268                         const struct object_id **oidp,
 269                         unsigned int *modep,
 270                         int cached, int match_missing,
 271                         unsigned *dirty_submodule, struct diff_options *diffopt)
 272{
 273        const struct object_id *oid = &ce->oid;
 274        unsigned int mode = ce->ce_mode;
 275
 276        if (!cached && !ce_uptodate(ce)) {
 277                int changed;
 278                struct stat st;
 279                changed = check_removed(ce, &st);
 280                if (changed < 0)
 281                        return -1;
 282                else if (changed) {
 283                        if (match_missing) {
 284                                *oidp = oid;
 285                                *modep = mode;
 286                                return 0;
 287                        }
 288                        return -1;
 289                }
 290                changed = match_stat_with_submodule(diffopt, ce, &st,
 291                                                    0, dirty_submodule);
 292                if (changed) {
 293                        mode = ce_mode_from_stat(ce, st.st_mode);
 294                        oid = &null_oid;
 295                }
 296        }
 297
 298        *oidp = oid;
 299        *modep = mode;
 300        return 0;
 301}
 302
 303static void show_new_file(struct rev_info *revs,
 304                          const struct cache_entry *new,
 305                          int cached, int match_missing)
 306{
 307        const struct object_id *oid;
 308        unsigned int mode;
 309        unsigned dirty_submodule = 0;
 310
 311        /*
 312         * New file in the index: it might actually be different in
 313         * the working tree.
 314         */
 315        if (get_stat_data(new, &oid, &mode, cached, match_missing,
 316            &dirty_submodule, &revs->diffopt) < 0)
 317                return;
 318
 319        diff_index_show_file(revs, "+", new, oid, !is_null_oid(oid), mode, dirty_submodule);
 320}
 321
 322static int show_modified(struct rev_info *revs,
 323                         const struct cache_entry *old,
 324                         const struct cache_entry *new,
 325                         int report_missing,
 326                         int cached, int match_missing)
 327{
 328        unsigned int mode, oldmode;
 329        const struct object_id *oid;
 330        unsigned dirty_submodule = 0;
 331
 332        if (get_stat_data(new, &oid, &mode, cached, match_missing,
 333                          &dirty_submodule, &revs->diffopt) < 0) {
 334                if (report_missing)
 335                        diff_index_show_file(revs, "-", old,
 336                                             &old->oid, 1, old->ce_mode,
 337                                             0);
 338                return -1;
 339        }
 340
 341        if (revs->combine_merges && !cached &&
 342            (oidcmp(oid, &old->oid) || oidcmp(&old->oid, &new->oid))) {
 343                struct combine_diff_path *p;
 344                int pathlen = ce_namelen(new);
 345
 346                p = xmalloc(combine_diff_path_size(2, pathlen));
 347                p->path = (char *) &p->parent[2];
 348                p->next = NULL;
 349                memcpy(p->path, new->name, pathlen);
 350                p->path[pathlen] = 0;
 351                p->mode = mode;
 352                oidclr(&p->oid);
 353                memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 354                p->parent[0].status = DIFF_STATUS_MODIFIED;
 355                p->parent[0].mode = new->ce_mode;
 356                oidcpy(&p->parent[0].oid, &new->oid);
 357                p->parent[1].status = DIFF_STATUS_MODIFIED;
 358                p->parent[1].mode = old->ce_mode;
 359                oidcpy(&p->parent[1].oid, &old->oid);
 360                show_combined_diff(p, 2, revs->dense_combined_merges, revs);
 361                free(p);
 362                return 0;
 363        }
 364
 365        oldmode = old->ce_mode;
 366        if (mode == oldmode && !oidcmp(oid, &old->oid) && !dirty_submodule &&
 367            !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
 368                return 0;
 369
 370        diff_change(&revs->diffopt, oldmode, mode,
 371                    &old->oid, oid, 1, !is_null_oid(oid),
 372                    old->name, 0, dirty_submodule);
 373        return 0;
 374}
 375
 376/*
 377 * This gets a mix of an existing index and a tree, one pathname entry
 378 * at a time. The index entry may be a single stage-0 one, but it could
 379 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
 380 * give you the position and number of entries in the index).
 381 */
 382static void do_oneway_diff(struct unpack_trees_options *o,
 383                           const struct cache_entry *idx,
 384                           const struct cache_entry *tree)
 385{
 386        struct rev_info *revs = o->unpack_data;
 387        int match_missing, cached;
 388
 389        /* i-t-a entries do not actually exist in the index */
 390        if (revs->diffopt.ita_invisible_in_index &&
 391            idx && ce_intent_to_add(idx)) {
 392                idx = NULL;
 393                if (!tree)
 394                        return; /* nothing to diff.. */
 395        }
 396
 397        /* if the entry is not checked out, don't examine work tree */
 398        cached = o->index_only ||
 399                (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
 400        /*
 401         * Backward compatibility wart - "diff-index -m" does
 402         * not mean "do not ignore merges", but "match_missing".
 403         *
 404         * But with the revision flag parsing, that's found in
 405         * "!revs->ignore_merges".
 406         */
 407        match_missing = !revs->ignore_merges;
 408
 409        if (cached && idx && ce_stage(idx)) {
 410                struct diff_filepair *pair;
 411                pair = diff_unmerge(&revs->diffopt, idx->name);
 412                if (tree)
 413                        fill_filespec(pair->one, &tree->oid, 1,
 414                                      tree->ce_mode);
 415                return;
 416        }
 417
 418        /*
 419         * Something added to the tree?
 420         */
 421        if (!tree) {
 422                show_new_file(revs, idx, cached, match_missing);
 423                return;
 424        }
 425
 426        /*
 427         * Something removed from the tree?
 428         */
 429        if (!idx) {
 430                diff_index_show_file(revs, "-", tree, &tree->oid, 1,
 431                                     tree->ce_mode, 0);
 432                return;
 433        }
 434
 435        /* Show difference between old and new */
 436        show_modified(revs, tree, idx, 1, cached, match_missing);
 437}
 438
 439/*
 440 * The unpack_trees() interface is designed for merging, so
 441 * the different source entries are designed primarily for
 442 * the source trees, with the old index being really mainly
 443 * used for being replaced by the result.
 444 *
 445 * For diffing, the index is more important, and we only have a
 446 * single tree.
 447 *
 448 * We're supposed to advance o->pos to skip what we have already processed.
 449 *
 450 * This wrapper makes it all more readable, and takes care of all
 451 * the fairly complex unpack_trees() semantic requirements, including
 452 * the skipping, the path matching, the type conflict cases etc.
 453 */
 454static int oneway_diff(const struct cache_entry * const *src,
 455                       struct unpack_trees_options *o)
 456{
 457        const struct cache_entry *idx = src[0];
 458        const struct cache_entry *tree = src[1];
 459        struct rev_info *revs = o->unpack_data;
 460
 461        /*
 462         * Unpack-trees generates a DF/conflict entry if
 463         * there was a directory in the index and a tree
 464         * in the tree. From a diff standpoint, that's a
 465         * delete of the tree and a create of the file.
 466         */
 467        if (tree == o->df_conflict_entry)
 468                tree = NULL;
 469
 470        if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
 471                do_oneway_diff(o, idx, tree);
 472                if (diff_can_quit_early(&revs->diffopt)) {
 473                        o->exiting_early = 1;
 474                        return -1;
 475                }
 476        }
 477
 478        return 0;
 479}
 480
 481static int diff_cache(struct rev_info *revs,
 482                      const struct object_id *tree_oid,
 483                      const char *tree_name,
 484                      int cached)
 485{
 486        struct tree *tree;
 487        struct tree_desc t;
 488        struct unpack_trees_options opts;
 489
 490        tree = parse_tree_indirect(tree_oid);
 491        if (!tree)
 492                return error("bad tree object %s",
 493                             tree_name ? tree_name : oid_to_hex(tree_oid));
 494        memset(&opts, 0, sizeof(opts));
 495        opts.head_idx = 1;
 496        opts.index_only = cached;
 497        opts.diff_index_cached = (cached &&
 498                                  !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
 499        opts.merge = 1;
 500        opts.fn = oneway_diff;
 501        opts.unpack_data = revs;
 502        opts.src_index = &the_index;
 503        opts.dst_index = NULL;
 504        opts.pathspec = &revs->diffopt.pathspec;
 505        opts.pathspec->recursive = 1;
 506
 507        init_tree_desc(&t, tree->buffer, tree->size);
 508        return unpack_trees(1, &t, &opts);
 509}
 510
 511int run_diff_index(struct rev_info *revs, int cached)
 512{
 513        struct object_array_entry *ent;
 514
 515        ent = revs->pending.objects;
 516        if (diff_cache(revs, &ent->item->oid, ent->name, cached))
 517                exit(128);
 518
 519        diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
 520        diffcore_fix_diff_index(&revs->diffopt);
 521        diffcore_std(&revs->diffopt);
 522        diff_flush(&revs->diffopt);
 523        return 0;
 524}
 525
 526int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
 527{
 528        struct rev_info revs;
 529
 530        init_revisions(&revs, NULL);
 531        copy_pathspec(&revs.prune_data, &opt->pathspec);
 532        revs.diffopt = *opt;
 533
 534        if (diff_cache(&revs, tree_oid, NULL, 1))
 535                exit(128);
 536        return 0;
 537}
 538
 539int index_differs_from(const char *def, int diff_flags,
 540                       int ita_invisible_in_index)
 541{
 542        struct rev_info rev;
 543        struct setup_revision_opt opt;
 544
 545        init_revisions(&rev, NULL);
 546        memset(&opt, 0, sizeof(opt));
 547        opt.def = def;
 548        setup_revisions(0, NULL, &rev, &opt);
 549        DIFF_OPT_SET(&rev.diffopt, QUICK);
 550        DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
 551        rev.diffopt.flags |= diff_flags;
 552        rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
 553        run_diff_index(&rev, 1);
 554        if (rev.pending.alloc)
 555                free(rev.pending.objects);
 556        return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
 557}