diff-lib.con commit run_hook(): check the executability of the hook before filling argv (cf94ca8)
   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
  14/*
  15 * diff-files
  16 */
  17
  18/*
  19 * Has the work tree entity been removed?
  20 *
  21 * Return 1 if it was removed from the work tree, 0 if an entity to be
  22 * compared with the cache entry ce still exists (the latter includes
  23 * the case where a directory that is not a submodule repository
  24 * exists for ce that is a submodule -- it is a submodule that is not
  25 * checked out).  Return negative for an error.
  26 */
  27static int check_removed(const struct cache_entry *ce, struct stat *st)
  28{
  29        if (lstat(ce->name, st) < 0) {
  30                if (errno != ENOENT && errno != ENOTDIR)
  31                        return -1;
  32                return 1;
  33        }
  34        if (has_symlink_leading_path(ce_namelen(ce), ce->name))
  35                return 1;
  36        if (S_ISDIR(st->st_mode)) {
  37                unsigned char sub[20];
  38
  39                /*
  40                 * If ce is already a gitlink, we can have a plain
  41                 * directory (i.e. the submodule is not checked out),
  42                 * or a checked out submodule.  Either case this is not
  43                 * a case where something was removed from the work tree,
  44                 * so we will return 0.
  45                 *
  46                 * Otherwise, if the directory is not a submodule
  47                 * repository, that means ce which was a blob turned into
  48                 * a directory --- the blob was removed!
  49                 */
  50                if (!S_ISGITLINK(ce->ce_mode) &&
  51                    resolve_gitlink_ref(ce->name, "HEAD", sub))
  52                        return 1;
  53        }
  54        return 0;
  55}
  56
  57int run_diff_files(struct rev_info *revs, unsigned int option)
  58{
  59        int entries, i;
  60        int diff_unmerged_stage = revs->max_count;
  61        int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
  62        unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
  63                              ? CE_MATCH_RACY_IS_DIRTY : 0);
  64
  65        diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
  66
  67        if (diff_unmerged_stage < 0)
  68                diff_unmerged_stage = 2;
  69        entries = active_nr;
  70        for (i = 0; i < entries; i++) {
  71                struct stat st;
  72                unsigned int oldmode, newmode;
  73                struct cache_entry *ce = active_cache[i];
  74                int changed;
  75
  76                if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
  77                        DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
  78                        break;
  79
  80                if (!ce_path_match(ce, revs->prune_data))
  81                        continue;
  82
  83                if (ce_stage(ce)) {
  84                        struct combine_diff_path *dpath;
  85                        int num_compare_stages = 0;
  86                        size_t path_len;
  87
  88                        path_len = ce_namelen(ce);
  89
  90                        dpath = xmalloc(combine_diff_path_size(5, path_len));
  91                        dpath->path = (char *) &(dpath->parent[5]);
  92
  93                        dpath->next = NULL;
  94                        dpath->len = path_len;
  95                        memcpy(dpath->path, ce->name, path_len);
  96                        dpath->path[path_len] = '\0';
  97                        hashclr(dpath->sha1);
  98                        memset(&(dpath->parent[0]), 0,
  99                               sizeof(struct combine_diff_parent)*5);
 100
 101                        changed = check_removed(ce, &st);
 102                        if (!changed)
 103                                dpath->mode = ce_mode_from_stat(ce, st.st_mode);
 104                        else {
 105                                if (changed < 0) {
 106                                        perror(ce->name);
 107                                        continue;
 108                                }
 109                                if (silent_on_removed)
 110                                        continue;
 111                        }
 112
 113                        while (i < entries) {
 114                                struct cache_entry *nce = active_cache[i];
 115                                int stage;
 116
 117                                if (strcmp(ce->name, nce->name))
 118                                        break;
 119
 120                                /* Stage #2 (ours) is the first parent,
 121                                 * stage #3 (theirs) is the second.
 122                                 */
 123                                stage = ce_stage(nce);
 124                                if (2 <= stage) {
 125                                        int mode = nce->ce_mode;
 126                                        num_compare_stages++;
 127                                        hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
 128                                        dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
 129                                        dpath->parent[stage-2].status =
 130                                                DIFF_STATUS_MODIFIED;
 131                                }
 132
 133                                /* diff against the proper unmerged stage */
 134                                if (stage == diff_unmerged_stage)
 135                                        ce = nce;
 136                                i++;
 137                        }
 138                        /*
 139                         * Compensate for loop update
 140                         */
 141                        i--;
 142
 143                        if (revs->combine_merges && num_compare_stages == 2) {
 144                                show_combined_diff(dpath, 2,
 145                                                   revs->dense_combined_merges,
 146                                                   revs);
 147                                free(dpath);
 148                                continue;
 149                        }
 150                        free(dpath);
 151                        dpath = NULL;
 152
 153                        /*
 154                         * Show the diff for the 'ce' if we found the one
 155                         * from the desired stage.
 156                         */
 157                        diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
 158                        if (ce_stage(ce) != diff_unmerged_stage)
 159                                continue;
 160                }
 161
 162                if (ce_uptodate(ce))
 163                        continue;
 164
 165                changed = check_removed(ce, &st);
 166                if (changed) {
 167                        if (changed < 0) {
 168                                perror(ce->name);
 169                                continue;
 170                        }
 171                        if (silent_on_removed)
 172                                continue;
 173                        diff_addremove(&revs->diffopt, '-', ce->ce_mode,
 174                                       ce->sha1, ce->name);
 175                        continue;
 176                }
 177                changed = ce_match_stat(ce, &st, ce_option);
 178                if (!changed) {
 179                        ce_mark_uptodate(ce);
 180                        if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
 181                                continue;
 182                }
 183                oldmode = ce->ce_mode;
 184                newmode = ce_mode_from_stat(ce, st.st_mode);
 185                diff_change(&revs->diffopt, oldmode, newmode,
 186                            ce->sha1, (changed ? null_sha1 : ce->sha1),
 187                            ce->name);
 188
 189        }
 190        diffcore_std(&revs->diffopt);
 191        diff_flush(&revs->diffopt);
 192        return 0;
 193}
 194
 195/*
 196 * diff-index
 197 */
 198
 199/* A file entry went away or appeared */
 200static void diff_index_show_file(struct rev_info *revs,
 201                                 const char *prefix,
 202                                 struct cache_entry *ce,
 203                                 const unsigned char *sha1, unsigned int mode)
 204{
 205        diff_addremove(&revs->diffopt, prefix[0], mode,
 206                       sha1, ce->name);
 207}
 208
 209static int get_stat_data(struct cache_entry *ce,
 210                         const unsigned char **sha1p,
 211                         unsigned int *modep,
 212                         int cached, int match_missing)
 213{
 214        const unsigned char *sha1 = ce->sha1;
 215        unsigned int mode = ce->ce_mode;
 216
 217        if (!cached) {
 218                int changed;
 219                struct stat st;
 220                changed = check_removed(ce, &st);
 221                if (changed < 0)
 222                        return -1;
 223                else if (changed) {
 224                        if (match_missing) {
 225                                *sha1p = sha1;
 226                                *modep = mode;
 227                                return 0;
 228                        }
 229                        return -1;
 230                }
 231                changed = ce_match_stat(ce, &st, 0);
 232                if (changed) {
 233                        mode = ce_mode_from_stat(ce, st.st_mode);
 234                        sha1 = null_sha1;
 235                }
 236        }
 237
 238        *sha1p = sha1;
 239        *modep = mode;
 240        return 0;
 241}
 242
 243static void show_new_file(struct rev_info *revs,
 244                          struct cache_entry *new,
 245                          int cached, int match_missing)
 246{
 247        const unsigned char *sha1;
 248        unsigned int mode;
 249
 250        /*
 251         * New file in the index: it might actually be different in
 252         * the working copy.
 253         */
 254        if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
 255                return;
 256
 257        diff_index_show_file(revs, "+", new, sha1, mode);
 258}
 259
 260static int show_modified(struct rev_info *revs,
 261                         struct cache_entry *old,
 262                         struct cache_entry *new,
 263                         int report_missing,
 264                         int cached, int match_missing)
 265{
 266        unsigned int mode, oldmode;
 267        const unsigned char *sha1;
 268
 269        if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
 270                if (report_missing)
 271                        diff_index_show_file(revs, "-", old,
 272                                             old->sha1, old->ce_mode);
 273                return -1;
 274        }
 275
 276        if (revs->combine_merges && !cached &&
 277            (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
 278                struct combine_diff_path *p;
 279                int pathlen = ce_namelen(new);
 280
 281                p = xmalloc(combine_diff_path_size(2, pathlen));
 282                p->path = (char *) &p->parent[2];
 283                p->next = NULL;
 284                p->len = pathlen;
 285                memcpy(p->path, new->name, pathlen);
 286                p->path[pathlen] = 0;
 287                p->mode = mode;
 288                hashclr(p->sha1);
 289                memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 290                p->parent[0].status = DIFF_STATUS_MODIFIED;
 291                p->parent[0].mode = new->ce_mode;
 292                hashcpy(p->parent[0].sha1, new->sha1);
 293                p->parent[1].status = DIFF_STATUS_MODIFIED;
 294                p->parent[1].mode = old->ce_mode;
 295                hashcpy(p->parent[1].sha1, old->sha1);
 296                show_combined_diff(p, 2, revs->dense_combined_merges, revs);
 297                free(p);
 298                return 0;
 299        }
 300
 301        oldmode = old->ce_mode;
 302        if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
 303            !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
 304                return 0;
 305
 306        diff_change(&revs->diffopt, oldmode, mode,
 307                    old->sha1, sha1, old->name);
 308        return 0;
 309}
 310
 311/*
 312 * This turns all merge entries into "stage 3". That guarantees that
 313 * when we read in the new tree (into "stage 1"), we won't lose sight
 314 * of the fact that we had unmerged entries.
 315 */
 316static void mark_merge_entries(void)
 317{
 318        int i;
 319        for (i = 0; i < active_nr; i++) {
 320                struct cache_entry *ce = active_cache[i];
 321                if (!ce_stage(ce))
 322                        continue;
 323                ce->ce_flags |= CE_STAGEMASK;
 324        }
 325}
 326
 327/*
 328 * This gets a mix of an existing index and a tree, one pathname entry
 329 * at a time. The index entry may be a single stage-0 one, but it could
 330 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
 331 * give you the position and number of entries in the index).
 332 */
 333static void do_oneway_diff(struct unpack_trees_options *o,
 334        struct cache_entry *idx,
 335        struct cache_entry *tree)
 336{
 337        struct rev_info *revs = o->unpack_data;
 338        int match_missing, cached;
 339
 340        /*
 341         * Backward compatibility wart - "diff-index -m" does
 342         * not mean "do not ignore merges", but "match_missing".
 343         *
 344         * But with the revision flag parsing, that's found in
 345         * "!revs->ignore_merges".
 346         */
 347        cached = o->index_only;
 348        match_missing = !revs->ignore_merges;
 349
 350        if (cached && idx && ce_stage(idx)) {
 351                if (tree)
 352                        diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode, idx->sha1);
 353                return;
 354        }
 355
 356        /*
 357         * Something added to the tree?
 358         */
 359        if (!tree) {
 360                show_new_file(revs, idx, cached, match_missing);
 361                return;
 362        }
 363
 364        /*
 365         * Something removed from the tree?
 366         */
 367        if (!idx) {
 368                diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode);
 369                return;
 370        }
 371
 372        /* Show difference between old and new */
 373        show_modified(revs, tree, idx, 1, cached, match_missing);
 374}
 375
 376static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
 377{
 378        int len = ce_namelen(ce);
 379        const struct index_state *index = o->src_index;
 380
 381        while (o->pos < index->cache_nr) {
 382                struct cache_entry *next = index->cache[o->pos];
 383                if (len != ce_namelen(next))
 384                        break;
 385                if (memcmp(ce->name, next->name, len))
 386                        break;
 387                o->pos++;
 388        }
 389}
 390
 391/*
 392 * The unpack_trees() interface is designed for merging, so
 393 * the different source entries are designed primarily for
 394 * the source trees, with the old index being really mainly
 395 * used for being replaced by the result.
 396 *
 397 * For diffing, the index is more important, and we only have a
 398 * single tree.
 399 *
 400 * We're supposed to return how many index entries we want to skip.
 401 *
 402 * This wrapper makes it all more readable, and takes care of all
 403 * the fairly complex unpack_trees() semantic requirements, including
 404 * the skipping, the path matching, the type conflict cases etc.
 405 */
 406static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
 407{
 408        struct cache_entry *idx = src[0];
 409        struct cache_entry *tree = src[1];
 410        struct rev_info *revs = o->unpack_data;
 411
 412        if (idx && ce_stage(idx))
 413                skip_same_name(idx, o);
 414
 415        /*
 416         * Unpack-trees generates a DF/conflict entry if
 417         * there was a directory in the index and a tree
 418         * in the tree. From a diff standpoint, that's a
 419         * delete of the tree and a create of the file.
 420         */
 421        if (tree == o->df_conflict_entry)
 422                tree = NULL;
 423
 424        if (ce_path_match(idx ? idx : tree, revs->prune_data))
 425                do_oneway_diff(o, idx, tree);
 426
 427        return 0;
 428}
 429
 430int run_diff_index(struct rev_info *revs, int cached)
 431{
 432        struct object *ent;
 433        struct tree *tree;
 434        const char *tree_name;
 435        struct unpack_trees_options opts;
 436        struct tree_desc t;
 437
 438        mark_merge_entries();
 439
 440        ent = revs->pending.objects[0].item;
 441        tree_name = revs->pending.objects[0].name;
 442        tree = parse_tree_indirect(ent->sha1);
 443        if (!tree)
 444                return error("bad tree object %s", tree_name);
 445
 446        memset(&opts, 0, sizeof(opts));
 447        opts.head_idx = 1;
 448        opts.index_only = cached;
 449        opts.merge = 1;
 450        opts.fn = oneway_diff;
 451        opts.unpack_data = revs;
 452        opts.src_index = &the_index;
 453        opts.dst_index = NULL;
 454
 455        init_tree_desc(&t, tree->buffer, tree->size);
 456        if (unpack_trees(1, &t, &opts))
 457                exit(128);
 458
 459        diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
 460        diffcore_std(&revs->diffopt);
 461        diff_flush(&revs->diffopt);
 462        return 0;
 463}
 464
 465int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 466{
 467        struct tree *tree;
 468        struct rev_info revs;
 469        int i;
 470        struct cache_entry **dst;
 471        struct cache_entry *last = NULL;
 472        struct unpack_trees_options opts;
 473        struct tree_desc t;
 474
 475        /*
 476         * This is used by git-blame to run diff-cache internally;
 477         * it potentially needs to repeatedly run this, so we will
 478         * start by removing the higher order entries the last round
 479         * left behind.
 480         */
 481        dst = active_cache;
 482        for (i = 0; i < active_nr; i++) {
 483                struct cache_entry *ce = active_cache[i];
 484                if (ce_stage(ce)) {
 485                        if (last && !strcmp(ce->name, last->name))
 486                                continue;
 487                        cache_tree_invalidate_path(active_cache_tree,
 488                                                   ce->name);
 489                        last = ce;
 490                        ce->ce_flags |= CE_REMOVE;
 491                }
 492                *dst++ = ce;
 493        }
 494        active_nr = dst - active_cache;
 495
 496        init_revisions(&revs, NULL);
 497        revs.prune_data = opt->paths;
 498        tree = parse_tree_indirect(tree_sha1);
 499        if (!tree)
 500                die("bad tree object %s", sha1_to_hex(tree_sha1));
 501
 502        memset(&opts, 0, sizeof(opts));
 503        opts.head_idx = 1;
 504        opts.index_only = 1;
 505        opts.merge = 1;
 506        opts.fn = oneway_diff;
 507        opts.unpack_data = &revs;
 508        opts.src_index = &the_index;
 509        opts.dst_index = &the_index;
 510
 511        init_tree_desc(&t, tree->buffer, tree->size);
 512        if (unpack_trees(1, &t, &opts))
 513                exit(128);
 514        return 0;
 515}