Andrew's git - gitweb.git/blob

   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
  12/*
  13 * diff-files
  14 */
  15
  16int run_diff_files(struct rev_info *revs, int silent_on_removed)
  17{
  18        int entries, i;
  19        int diff_unmerged_stage = revs->max_count;
  20
  21        if (diff_unmerged_stage < 0)
  22                diff_unmerged_stage = 2;
  23        entries = active_nr;
  24        for (i = 0; i < entries; i++) {
  25                struct stat st;
  26                unsigned int oldmode, newmode;
  27                struct cache_entry *ce = active_cache[i];
  28                int changed;
  29
  30                if (!ce_path_match(ce, revs->prune_data))
  31                        continue;
  32
  33                if (ce_stage(ce)) {
  34                        struct combine_diff_path *dpath;
  35                        int num_compare_stages = 0;
  36                        size_t path_len;
  37
  38                        path_len = ce_namelen(ce);
  39
  40                        dpath = xmalloc (combine_diff_path_size (5, path_len));
  41                        dpath->path = (char *) &(dpath->parent[5]);
  42
  43                        dpath->next = NULL;
  44                        dpath->len = path_len;
  45                        memcpy(dpath->path, ce->name, path_len);
  46                        dpath->path[path_len] = '\0';
  47                        dpath->mode = 0;
  48                        hashclr(dpath->sha1);
  49                        memset(&(dpath->parent[0]), 0,
  50                                        sizeof(struct combine_diff_parent)*5);
  51
  52                        while (i < entries) {
  53                                struct cache_entry *nce = active_cache[i];
  54                                int stage;
  55
  56                                if (strcmp(ce->name, nce->name))
  57                                        break;
  58
  59                                /* Stage #2 (ours) is the first parent,
  60                                 * stage #3 (theirs) is the second.
  61                                 */
  62                                stage = ce_stage(nce);
  63                                if (2 <= stage) {
  64                                        int mode = ntohl(nce->ce_mode);
  65                                        num_compare_stages++;
  66                                        hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
  67                                        dpath->parent[stage-2].mode =
  68                                                canon_mode(mode);
  69                                        dpath->parent[stage-2].status =
  70                                                DIFF_STATUS_MODIFIED;
  71                                }
  72
  73                                /* diff against the proper unmerged stage */
  74                                if (stage == diff_unmerged_stage)
  75                                        ce = nce;
  76                                i++;
  77                        }
  78                        /*
  79                         * Compensate for loop update
  80                         */
  81                        i--;
  82
  83                        if (revs->combine_merges && num_compare_stages == 2) {
  84                                show_combined_diff(dpath, 2,
  85                                                   revs->dense_combined_merges,
  86                                                   revs);
  87                                free(dpath);
  88                                continue;
  89                        }
  90                        free(dpath);
  91                        dpath = NULL;
  92
  93                        /*
  94                         * Show the diff for the 'ce' if we found the one
  95                         * from the desired stage.
  96                         */
  97                        diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
  98                        if (ce_stage(ce) != diff_unmerged_stage)
  99                                continue;
 100                }
 101
 102                if (lstat(ce->name, &st) < 0) {
 103                        if (errno != ENOENT && errno != ENOTDIR) {
 104                                perror(ce->name);
 105                                continue;
 106                        }
 107                        if (silent_on_removed)
 108                                continue;
 109                        diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
 110                                       ce->sha1, ce->name, NULL);
 111                        continue;
 112                }
 113                changed = ce_match_stat(ce, &st, 0);
 114                if (!changed && !revs->diffopt.find_copies_harder)
 115                        continue;
 116                oldmode = ntohl(ce->ce_mode);
 117
 118                newmode = canon_mode(st.st_mode);
 119                if (!trust_executable_bit &&
 120                    S_ISREG(newmode) && S_ISREG(oldmode) &&
 121                    ((newmode ^ oldmode) == 0111))
 122                        newmode = oldmode;
 123                diff_change(&revs->diffopt, oldmode, newmode,
 124                            ce->sha1, (changed ? null_sha1 : ce->sha1),
 125                            ce->name, NULL);
 126
 127        }
 128        diffcore_std(&revs->diffopt);
 129        diff_flush(&revs->diffopt);
 130        return 0;
 131}
 132
 133/*
 134 * diff-index
 135 */
 136
 137/* A file entry went away or appeared */
 138static void diff_index_show_file(struct rev_info *revs,
 139                                 const char *prefix,
 140                                 struct cache_entry *ce,
 141                                 unsigned char *sha1, unsigned int mode)
 142{
 143        diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
 144                       sha1, ce->name, NULL);
 145}
 146
 147static int get_stat_data(struct cache_entry *ce,
 148                         unsigned char **sha1p,
 149                         unsigned int *modep,
 150                         int cached, int match_missing)
 151{
 152        unsigned char *sha1 = ce->sha1;
 153        unsigned int mode = ce->ce_mode;
 154
 155        if (!cached) {
 156                static unsigned char no_sha1[20];
 157                int changed;
 158                struct stat st;
 159                if (lstat(ce->name, &st) < 0) {
 160                        if (errno == ENOENT && match_missing) {
 161                                *sha1p = sha1;
 162                                *modep = mode;
 163                                return 0;
 164                        }
 165                        return -1;
 166                }
 167                changed = ce_match_stat(ce, &st, 0);
 168                if (changed) {
 169                        mode = create_ce_mode(st.st_mode);
 170                        if (!trust_executable_bit && S_ISREG(st.st_mode))
 171                                mode = ce->ce_mode;
 172                        sha1 = no_sha1;
 173                }
 174        }
 175
 176        *sha1p = sha1;
 177        *modep = mode;
 178        return 0;
 179}
 180
 181static void show_new_file(struct rev_info *revs,
 182                          struct cache_entry *new,
 183                          int cached, int match_missing)
 184{
 185        unsigned char *sha1;
 186        unsigned int mode;
 187
 188        /* New file in the index: it might actually be different in
 189         * the working copy.
 190         */
 191        if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
 192                return;
 193
 194        diff_index_show_file(revs, "+", new, sha1, mode);
 195}
 196
 197static int show_modified(struct rev_info *revs,
 198                         struct cache_entry *old,
 199                         struct cache_entry *new,
 200                         int report_missing,
 201                         int cached, int match_missing)
 202{
 203        unsigned int mode, oldmode;
 204        unsigned char *sha1;
 205
 206        if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
 207                if (report_missing)
 208                        diff_index_show_file(revs, "-", old,
 209                                             old->sha1, old->ce_mode);
 210                return -1;
 211        }
 212
 213        if (revs->combine_merges && !cached &&
 214            (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
 215                struct combine_diff_path *p;
 216                int pathlen = ce_namelen(new);
 217
 218                p = xmalloc(combine_diff_path_size(2, pathlen));
 219                p->path = (char *) &p->parent[2];
 220                p->next = NULL;
 221                p->len = pathlen;
 222                memcpy(p->path, new->name, pathlen);
 223                p->path[pathlen] = 0;
 224                p->mode = ntohl(mode);
 225                hashclr(p->sha1);
 226                memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 227                p->parent[0].status = DIFF_STATUS_MODIFIED;
 228                p->parent[0].mode = ntohl(new->ce_mode);
 229                hashcpy(p->parent[0].sha1, new->sha1);
 230                p->parent[1].status = DIFF_STATUS_MODIFIED;
 231                p->parent[1].mode = ntohl(old->ce_mode);
 232                hashcpy(p->parent[1].sha1, old->sha1);
 233                show_combined_diff(p, 2, revs->dense_combined_merges, revs);
 234                free(p);
 235                return 0;
 236        }
 237
 238        oldmode = old->ce_mode;
 239        if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
 240            !revs->diffopt.find_copies_harder)
 241                return 0;
 242
 243        mode = ntohl(mode);
 244        oldmode = ntohl(oldmode);
 245
 246        diff_change(&revs->diffopt, oldmode, mode,
 247                    old->sha1, sha1, old->name, NULL);
 248        return 0;
 249}
 250
 251static int diff_cache(struct rev_info *revs,
 252                      struct cache_entry **ac, int entries,
 253                      const char **pathspec,
 254                      int cached, int match_missing)
 255{
 256        while (entries) {
 257                struct cache_entry *ce = *ac;
 258                int same = (entries > 1) && ce_same_name(ce, ac[1]);
 259
 260                if (!ce_path_match(ce, pathspec))
 261                        goto skip_entry;
 262
 263                switch (ce_stage(ce)) {
 264                case 0:
 265                        /* No stage 1 entry? That means it's a new file */
 266                        if (!same) {
 267                                show_new_file(revs, ce, cached, match_missing);
 268                                break;
 269                        }
 270                        /* Show difference between old and new */
 271                        show_modified(revs, ac[1], ce, 1,
 272                                      cached, match_missing);
 273                        break;
 274                case 1:
 275                        /* No stage 3 (merge) entry?
 276                         * That means it's been deleted.
 277                         */
 278                        if (!same) {
 279                                diff_index_show_file(revs, "-", ce,
 280                                                     ce->sha1, ce->ce_mode);
 281                                break;
 282                        }
 283                        /* We come here with ce pointing at stage 1
 284                         * (original tree) and ac[1] pointing at stage
 285                         * 3 (unmerged).  show-modified with
 286                         * report-missing set to false does not say the
 287                         * file is deleted but reports true if work
 288                         * tree does not have it, in which case we
 289                         * fall through to report the unmerged state.
 290                         * Otherwise, we show the differences between
 291                         * the original tree and the work tree.
 292                         */
 293                        if (!cached &&
 294                            !show_modified(revs, ce, ac[1], 0,
 295                                           cached, match_missing))
 296                                break;
 297                        diff_unmerge(&revs->diffopt, ce->name,
 298                                     ntohl(ce->ce_mode), ce->sha1);
 299                        break;
 300                case 3:
 301                        diff_unmerge(&revs->diffopt, ce->name,
 302                                     0, null_sha1);
 303                        break;
 304
 305                default:
 306                        die("impossible cache entry stage");
 307                }
 308
 309skip_entry:
 310                /*
 311                 * Ignore all the different stages for this file,
 312                 * we've handled the relevant cases now.
 313                 */
 314                do {
 315                        ac++;
 316                        entries--;
 317                } while (entries && ce_same_name(ce, ac[0]));
 318        }
 319        return 0;
 320}
 321
 322/*
 323 * This turns all merge entries into "stage 3". That guarantees that
 324 * when we read in the new tree (into "stage 1"), we won't lose sight
 325 * of the fact that we had unmerged entries.
 326 */
 327static void mark_merge_entries(void)
 328{
 329        int i;
 330        for (i = 0; i < active_nr; i++) {
 331                struct cache_entry *ce = active_cache[i];
 332                if (!ce_stage(ce))
 333                        continue;
 334                ce->ce_flags |= htons(CE_STAGEMASK);
 335        }
 336}
 337
 338int run_diff_index(struct rev_info *revs, int cached)
 339{
 340        int ret;
 341        struct object *ent;
 342        struct tree *tree;
 343        const char *tree_name;
 344        int match_missing = 0;
 345
 346        /* 
 347         * Backward compatibility wart - "diff-index -m" does
 348         * not mean "do not ignore merges", but totally different.
 349         */
 350        if (!revs->ignore_merges)
 351                match_missing = 1;
 352
 353        mark_merge_entries();
 354
 355        ent = revs->pending.objects[0].item;
 356        tree_name = revs->pending.objects[0].name;
 357        tree = parse_tree_indirect(ent->sha1);
 358        if (!tree)
 359                return error("bad tree object %s", tree_name);
 360        if (read_tree(tree, 1, revs->prune_data))
 361                return error("unable to read tree object %s", tree_name);
 362        ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
 363                         cached, match_missing);
 364        diffcore_std(&revs->diffopt);
 365        diff_flush(&revs->diffopt);
 366        return ret;
 367}
 368
 369int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 370{
 371        struct tree *tree;
 372        struct rev_info revs;
 373        int i;
 374        struct cache_entry **dst;
 375        struct cache_entry *last = NULL;
 376
 377        /*
 378         * This is used by git-blame to run diff-cache internally;
 379         * it potentially needs to repeatedly run this, so we will
 380         * start by removing the higher order entries the last round
 381         * left behind.
 382         */
 383        dst = active_cache;
 384        for (i = 0; i < active_nr; i++) {
 385                struct cache_entry *ce = active_cache[i];
 386                if (ce_stage(ce)) {
 387                        if (last && !strcmp(ce->name, last->name))
 388                                continue;
 389                        cache_tree_invalidate_path(active_cache_tree,
 390                                                   ce->name);
 391                        last = ce;
 392                        ce->ce_mode = 0;
 393                        ce->ce_flags &= ~htons(CE_STAGEMASK);
 394                }
 395                *dst++ = ce;
 396        }
 397        active_nr = dst - active_cache;
 398
 399        init_revisions(&revs, NULL);
 400        revs.prune_data = opt->paths;
 401        tree = parse_tree_indirect(tree_sha1);
 402        if (!tree)
 403                die("bad tree object %s", sha1_to_hex(tree_sha1));
 404        if (read_tree(tree, 1, opt->paths))
 405                return error("unable to read tree %s", sha1_to_hex(tree_sha1));
 406        return diff_cache(&revs, active_cache, active_nr, revs.prune_data,
 407                          1, 0);
 408}