diff-lib.con commit Merge branch 'mg/maint-send-email-lazy-editor' into maint (fe7e372)
   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
  15/*
  16 * diff-files
  17 */
  18
  19/*
  20 * Has the work tree entity been removed?
  21 *
  22 * Return 1 if it was removed from the work tree, 0 if an entity to be
  23 * compared with the cache entry ce still exists (the latter includes
  24 * the case where a directory that is not a submodule repository
  25 * exists for ce that is a submodule -- it is a submodule that is not
  26 * checked out).  Return negative for an error.
  27 */
  28static int check_removed(const struct cache_entry *ce, struct stat *st)
  29{
  30        if (lstat(ce->name, st) < 0) {
  31                if (errno != ENOENT && errno != ENOTDIR)
  32                        return -1;
  33                return 1;
  34        }
  35        if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
  36                return 1;
  37        if (S_ISDIR(st->st_mode)) {
  38                unsigned char sub[20];
  39
  40                /*
  41                 * If ce is already a gitlink, we can have a plain
  42                 * directory (i.e. the submodule is not checked out),
  43                 * or a checked out submodule.  Either case this is not
  44                 * a case where something was removed from the work tree,
  45                 * so we will return 0.
  46                 *
  47                 * Otherwise, if the directory is not a submodule
  48                 * repository, that means ce which was a blob turned into
  49                 * a directory --- the blob was removed!
  50                 */
  51                if (!S_ISGITLINK(ce->ce_mode) &&
  52                    resolve_gitlink_ref(ce->name, "HEAD", sub))
  53                        return 1;
  54        }
  55        return 0;
  56}
  57
  58int run_diff_files(struct rev_info *revs, unsigned int option)
  59{
  60        int entries, i;
  61        int diff_unmerged_stage = revs->max_count;
  62        int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
  63        unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
  64                              ? CE_MATCH_RACY_IS_DIRTY : 0);
  65
  66        diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
  67
  68        if (diff_unmerged_stage < 0)
  69                diff_unmerged_stage = 2;
  70        entries = active_nr;
  71        for (i = 0; i < entries; i++) {
  72                struct stat st;
  73                unsigned int oldmode, newmode;
  74                struct cache_entry *ce = active_cache[i];
  75                int changed;
  76                unsigned dirty_submodule = 0;
  77
  78                if (DIFF_OPT_TST(&revs->diffopt, QUICK) &&
  79                        DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
  80                        break;
  81
  82                if (!ce_path_match(ce, revs->prune_data))
  83                        continue;
  84
  85                if (ce_stage(ce)) {
  86                        struct combine_diff_path *dpath;
  87                        int num_compare_stages = 0;
  88                        size_t path_len;
  89
  90                        path_len = ce_namelen(ce);
  91
  92                        dpath = xmalloc(combine_diff_path_size(5, path_len));
  93                        dpath->path = (char *) &(dpath->parent[5]);
  94
  95                        dpath->next = NULL;
  96                        dpath->len = path_len;
  97                        memcpy(dpath->path, ce->name, path_len);
  98                        dpath->path[path_len] = '\0';
  99                        hashclr(dpath->sha1);
 100                        memset(&(dpath->parent[0]), 0,
 101                               sizeof(struct combine_diff_parent)*5);
 102
 103                        changed = check_removed(ce, &st);
 104                        if (!changed)
 105                                dpath->mode = ce_mode_from_stat(ce, st.st_mode);
 106                        else {
 107                                if (changed < 0) {
 108                                        perror(ce->name);
 109                                        continue;
 110                                }
 111                                if (silent_on_removed)
 112                                        continue;
 113                        }
 114
 115                        while (i < entries) {
 116                                struct cache_entry *nce = active_cache[i];
 117                                int stage;
 118
 119                                if (strcmp(ce->name, nce->name))
 120                                        break;
 121
 122                                /* Stage #2 (ours) is the first parent,
 123                                 * stage #3 (theirs) is the second.
 124                                 */
 125                                stage = ce_stage(nce);
 126                                if (2 <= stage) {
 127                                        int mode = nce->ce_mode;
 128                                        num_compare_stages++;
 129                                        hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
 130                                        dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
 131                                        dpath->parent[stage-2].status =
 132                                                DIFF_STATUS_MODIFIED;
 133                                }
 134
 135                                /* diff against the proper unmerged stage */
 136                                if (stage == diff_unmerged_stage)
 137                                        ce = nce;
 138                                i++;
 139                        }
 140                        /*
 141                         * Compensate for loop update
 142                         */
 143                        i--;
 144
 145                        if (revs->combine_merges && num_compare_stages == 2) {
 146                                show_combined_diff(dpath, 2,
 147                                                   revs->dense_combined_merges,
 148                                                   revs);
 149                                free(dpath);
 150                                continue;
 151                        }
 152                        free(dpath);
 153                        dpath = NULL;
 154
 155                        /*
 156                         * Show the diff for the 'ce' if we found the one
 157                         * from the desired stage.
 158                         */
 159                        diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
 160                        if (ce_stage(ce) != diff_unmerged_stage)
 161                                continue;
 162                }
 163
 164                if (ce_uptodate(ce) || ce_skip_worktree(ce))
 165                        continue;
 166
 167                /* If CE_VALID is set, don't look at workdir for file removal */
 168                changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
 169                if (changed) {
 170                        if (changed < 0) {
 171                                perror(ce->name);
 172                                continue;
 173                        }
 174                        if (silent_on_removed)
 175                                continue;
 176                        diff_addremove(&revs->diffopt, '-', ce->ce_mode,
 177                                       ce->sha1, ce->name, 0);
 178                        continue;
 179                }
 180                changed = ce_match_stat(ce, &st, ce_option);
 181                if (S_ISGITLINK(ce->ce_mode)
 182                    && !DIFF_OPT_TST(&revs->diffopt, IGNORE_SUBMODULES)
 183                    && (!changed || (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
 184                    && is_submodule_modified(ce->name)) {
 185                        changed = 1;
 186                        dirty_submodule = 1;
 187                }
 188                if (!changed) {
 189                        ce_mark_uptodate(ce);
 190                        if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
 191                                continue;
 192                }
 193                oldmode = ce->ce_mode;
 194                newmode = ce_mode_from_stat(ce, st.st_mode);
 195                diff_change(&revs->diffopt, oldmode, newmode,
 196                            ce->sha1, (changed ? null_sha1 : ce->sha1),
 197                            ce->name, 0, dirty_submodule);
 198
 199        }
 200        diffcore_std(&revs->diffopt);
 201        diff_flush(&revs->diffopt);
 202        return 0;
 203}
 204
 205/*
 206 * diff-index
 207 */
 208
 209/* A file entry went away or appeared */
 210static void diff_index_show_file(struct rev_info *revs,
 211                                 const char *prefix,
 212                                 struct cache_entry *ce,
 213                                 const unsigned char *sha1, unsigned int mode,
 214                                 unsigned dirty_submodule)
 215{
 216        diff_addremove(&revs->diffopt, prefix[0], mode,
 217                       sha1, ce->name, dirty_submodule);
 218}
 219
 220static int get_stat_data(struct cache_entry *ce,
 221                         const unsigned char **sha1p,
 222                         unsigned int *modep,
 223                         int cached, int match_missing,
 224                         unsigned *dirty_submodule, struct diff_options *diffopt)
 225{
 226        const unsigned char *sha1 = ce->sha1;
 227        unsigned int mode = ce->ce_mode;
 228
 229        if (!cached && !ce_uptodate(ce)) {
 230                int changed;
 231                struct stat st;
 232                changed = check_removed(ce, &st);
 233                if (changed < 0)
 234                        return -1;
 235                else if (changed) {
 236                        if (match_missing) {
 237                                *sha1p = sha1;
 238                                *modep = mode;
 239                                return 0;
 240                        }
 241                        return -1;
 242                }
 243                changed = ce_match_stat(ce, &st, 0);
 244                if (S_ISGITLINK(ce->ce_mode)
 245                    && !DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES)
 246                    && (!changed || (diffopt->output_format & DIFF_FORMAT_PATCH))
 247                    && is_submodule_modified(ce->name)) {
 248                        changed = 1;
 249                        *dirty_submodule = 1;
 250                }
 251                if (changed) {
 252                        mode = ce_mode_from_stat(ce, st.st_mode);
 253                        sha1 = null_sha1;
 254                }
 255        }
 256
 257        *sha1p = sha1;
 258        *modep = mode;
 259        return 0;
 260}
 261
 262static void show_new_file(struct rev_info *revs,
 263                          struct cache_entry *new,
 264                          int cached, int match_missing)
 265{
 266        const unsigned char *sha1;
 267        unsigned int mode;
 268        unsigned dirty_submodule = 0;
 269
 270        /*
 271         * New file in the index: it might actually be different in
 272         * the working copy.
 273         */
 274        if (get_stat_data(new, &sha1, &mode, cached, match_missing,
 275            &dirty_submodule, &revs->diffopt) < 0)
 276                return;
 277
 278        diff_index_show_file(revs, "+", new, sha1, mode, dirty_submodule);
 279}
 280
 281static int show_modified(struct rev_info *revs,
 282                         struct cache_entry *old,
 283                         struct cache_entry *new,
 284                         int report_missing,
 285                         int cached, int match_missing)
 286{
 287        unsigned int mode, oldmode;
 288        const unsigned char *sha1;
 289        unsigned dirty_submodule = 0;
 290
 291        if (get_stat_data(new, &sha1, &mode, cached, match_missing,
 292                          &dirty_submodule, &revs->diffopt) < 0) {
 293                if (report_missing)
 294                        diff_index_show_file(revs, "-", old,
 295                                             old->sha1, old->ce_mode, 0);
 296                return -1;
 297        }
 298
 299        if (revs->combine_merges && !cached &&
 300            (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
 301                struct combine_diff_path *p;
 302                int pathlen = ce_namelen(new);
 303
 304                p = xmalloc(combine_diff_path_size(2, pathlen));
 305                p->path = (char *) &p->parent[2];
 306                p->next = NULL;
 307                p->len = pathlen;
 308                memcpy(p->path, new->name, pathlen);
 309                p->path[pathlen] = 0;
 310                p->mode = mode;
 311                hashclr(p->sha1);
 312                memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 313                p->parent[0].status = DIFF_STATUS_MODIFIED;
 314                p->parent[0].mode = new->ce_mode;
 315                hashcpy(p->parent[0].sha1, new->sha1);
 316                p->parent[1].status = DIFF_STATUS_MODIFIED;
 317                p->parent[1].mode = old->ce_mode;
 318                hashcpy(p->parent[1].sha1, old->sha1);
 319                show_combined_diff(p, 2, revs->dense_combined_merges, revs);
 320                free(p);
 321                return 0;
 322        }
 323
 324        oldmode = old->ce_mode;
 325        if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
 326            !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
 327                return 0;
 328
 329        diff_change(&revs->diffopt, oldmode, mode,
 330                    old->sha1, sha1, old->name, 0, dirty_submodule);
 331        return 0;
 332}
 333
 334/*
 335 * This gets a mix of an existing index and a tree, one pathname entry
 336 * at a time. The index entry may be a single stage-0 one, but it could
 337 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
 338 * give you the position and number of entries in the index).
 339 */
 340static void do_oneway_diff(struct unpack_trees_options *o,
 341        struct cache_entry *idx,
 342        struct cache_entry *tree)
 343{
 344        struct rev_info *revs = o->unpack_data;
 345        int match_missing, cached;
 346
 347        /* if the entry is not checked out, don't examine work tree */
 348        cached = o->index_only ||
 349                (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
 350        /*
 351         * Backward compatibility wart - "diff-index -m" does
 352         * not mean "do not ignore merges", but "match_missing".
 353         *
 354         * But with the revision flag parsing, that's found in
 355         * "!revs->ignore_merges".
 356         */
 357        match_missing = !revs->ignore_merges;
 358
 359        if (cached && idx && ce_stage(idx)) {
 360                diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode,
 361                             idx->sha1);
 362                return;
 363        }
 364
 365        /*
 366         * Something added to the tree?
 367         */
 368        if (!tree) {
 369                show_new_file(revs, idx, cached, match_missing);
 370                return;
 371        }
 372
 373        /*
 374         * Something removed from the tree?
 375         */
 376        if (!idx) {
 377                diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode, 0);
 378                return;
 379        }
 380
 381        /* Show difference between old and new */
 382        show_modified(revs, tree, idx, 1, cached, match_missing);
 383}
 384
 385/*
 386 * The unpack_trees() interface is designed for merging, so
 387 * the different source entries are designed primarily for
 388 * the source trees, with the old index being really mainly
 389 * used for being replaced by the result.
 390 *
 391 * For diffing, the index is more important, and we only have a
 392 * single tree.
 393 *
 394 * We're supposed to advance o->pos to skip what we have already processed.
 395 *
 396 * This wrapper makes it all more readable, and takes care of all
 397 * the fairly complex unpack_trees() semantic requirements, including
 398 * the skipping, the path matching, the type conflict cases etc.
 399 */
 400static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
 401{
 402        struct cache_entry *idx = src[0];
 403        struct cache_entry *tree = src[1];
 404        struct rev_info *revs = o->unpack_data;
 405
 406        /*
 407         * Unpack-trees generates a DF/conflict entry if
 408         * there was a directory in the index and a tree
 409         * in the tree. From a diff standpoint, that's a
 410         * delete of the tree and a create of the file.
 411         */
 412        if (tree == o->df_conflict_entry)
 413                tree = NULL;
 414
 415        if (ce_path_match(idx ? idx : tree, revs->prune_data))
 416                do_oneway_diff(o, idx, tree);
 417
 418        return 0;
 419}
 420
 421int run_diff_index(struct rev_info *revs, int cached)
 422{
 423        struct object *ent;
 424        struct tree *tree;
 425        const char *tree_name;
 426        struct unpack_trees_options opts;
 427        struct tree_desc t;
 428
 429        ent = revs->pending.objects[0].item;
 430        tree_name = revs->pending.objects[0].name;
 431        tree = parse_tree_indirect(ent->sha1);
 432        if (!tree)
 433                return error("bad tree object %s", tree_name);
 434
 435        memset(&opts, 0, sizeof(opts));
 436        opts.head_idx = 1;
 437        opts.index_only = cached;
 438        opts.diff_index_cached = (cached &&
 439                                  !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
 440        opts.merge = 1;
 441        opts.fn = oneway_diff;
 442        opts.unpack_data = revs;
 443        opts.src_index = &the_index;
 444        opts.dst_index = NULL;
 445
 446        init_tree_desc(&t, tree->buffer, tree->size);
 447        if (unpack_trees(1, &t, &opts))
 448                exit(128);
 449
 450        diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
 451        diffcore_fix_diff_index(&revs->diffopt);
 452        diffcore_std(&revs->diffopt);
 453        diff_flush(&revs->diffopt);
 454        return 0;
 455}
 456
 457int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 458{
 459        struct tree *tree;
 460        struct rev_info revs;
 461        int i;
 462        struct cache_entry **dst;
 463        struct cache_entry *last = NULL;
 464        struct unpack_trees_options opts;
 465        struct tree_desc t;
 466
 467        /*
 468         * This is used by git-blame to run diff-cache internally;
 469         * it potentially needs to repeatedly run this, so we will
 470         * start by removing the higher order entries the last round
 471         * left behind.
 472         */
 473        dst = active_cache;
 474        for (i = 0; i < active_nr; i++) {
 475                struct cache_entry *ce = active_cache[i];
 476                if (ce_stage(ce)) {
 477                        if (last && !strcmp(ce->name, last->name))
 478                                continue;
 479                        cache_tree_invalidate_path(active_cache_tree,
 480                                                   ce->name);
 481                        last = ce;
 482                        ce->ce_flags |= CE_REMOVE;
 483                }
 484                *dst++ = ce;
 485        }
 486        active_nr = dst - active_cache;
 487
 488        init_revisions(&revs, NULL);
 489        revs.prune_data = opt->paths;
 490        tree = parse_tree_indirect(tree_sha1);
 491        if (!tree)
 492                die("bad tree object %s", sha1_to_hex(tree_sha1));
 493
 494        memset(&opts, 0, sizeof(opts));
 495        opts.head_idx = 1;
 496        opts.index_only = 1;
 497        opts.diff_index_cached = !DIFF_OPT_TST(opt, FIND_COPIES_HARDER);
 498        opts.merge = 1;
 499        opts.fn = oneway_diff;
 500        opts.unpack_data = &revs;
 501        opts.src_index = &the_index;
 502        opts.dst_index = &the_index;
 503
 504        init_tree_desc(&t, tree->buffer, tree->size);
 505        if (unpack_trees(1, &t, &opts))
 506                exit(128);
 507        return 0;
 508}
 509
 510int index_differs_from(const char *def, int diff_flags)
 511{
 512        struct rev_info rev;
 513
 514        init_revisions(&rev, NULL);
 515        setup_revisions(0, NULL, &rev, def);
 516        DIFF_OPT_SET(&rev.diffopt, QUICK);
 517        DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
 518        rev.diffopt.flags |= diff_flags;
 519        run_diff_index(&rev, 1);
 520        if (rev.pending.alloc)
 521                free(rev.pending.objects);
 522        return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
 523}