diff-lib.con commit Make git-revert & git-cherry-pick a builtin (9509af6)
   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 "path-list.h"
  12
  13/*
  14 * diff-files
  15 */
  16
  17static int read_directory(const char *path, struct path_list *list)
  18{
  19        DIR *dir;
  20        struct dirent *e;
  21
  22        if (!(dir = opendir(path)))
  23                return error("Could not open directory %s", path);
  24
  25        while ((e = readdir(dir)))
  26                if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
  27                        path_list_insert(xstrdup(e->d_name), list);
  28
  29        closedir(dir);
  30        return 0;
  31}
  32
  33static int queue_diff(struct diff_options *o,
  34                const char *name1, const char *name2)
  35{
  36        struct stat st;
  37        int mode1 = 0, mode2 = 0;
  38
  39        if (name1) {
  40                if (stat(name1, &st))
  41                        return error("Could not access '%s'", name1);
  42                mode1 = st.st_mode;
  43        }
  44        if (name2) {
  45                if (stat(name2, &st))
  46                        return error("Could not access '%s'", name2);
  47                mode2 = st.st_mode;
  48        }
  49
  50        if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
  51                return error("file/directory conflict: %s, %s", name1, name2);
  52
  53        if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
  54                char buffer1[PATH_MAX], buffer2[PATH_MAX];
  55                struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
  56                int len1 = 0, len2 = 0, i1, i2, ret = 0;
  57
  58                if (name1 && read_directory(name1, &p1))
  59                        return -1;
  60                if (name2 && read_directory(name2, &p2)) {
  61                        path_list_clear(&p1, 0);
  62                        return -1;
  63                }
  64
  65                if (name1) {
  66                        len1 = strlen(name1);
  67                        if (len1 > 0 && name1[len1 - 1] == '/')
  68                                len1--;
  69                        memcpy(buffer1, name1, len1);
  70                        buffer1[len1++] = '/';
  71                }
  72
  73                if (name2) {
  74                        len2 = strlen(name2);
  75                        if (len2 > 0 && name2[len2 - 1] == '/')
  76                                len2--;
  77                        memcpy(buffer2, name2, len2);
  78                        buffer2[len2++] = '/';
  79                }
  80
  81                for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
  82                        const char *n1, *n2;
  83                        int comp;
  84
  85                        if (i1 == p1.nr)
  86                                comp = 1;
  87                        else if (i2 == p2.nr)
  88                                comp = -1;
  89                        else
  90                                comp = strcmp(p1.items[i1].path,
  91                                        p2.items[i2].path);
  92
  93                        if (comp > 0)
  94                                n1 = NULL;
  95                        else {
  96                                n1 = buffer1;
  97                                strncpy(buffer1 + len1, p1.items[i1++].path,
  98                                                PATH_MAX - len1);
  99                        }
 100
 101                        if (comp < 0)
 102                                n2 = NULL;
 103                        else {
 104                                n2 = buffer2;
 105                                strncpy(buffer2 + len2, p2.items[i2++].path,
 106                                                PATH_MAX - len2);
 107                        }
 108
 109                        ret = queue_diff(o, n1, n2);
 110                }
 111                path_list_clear(&p1, 0);
 112                path_list_clear(&p2, 0);
 113
 114                return ret;
 115        } else {
 116                struct diff_filespec *d1, *d2;
 117
 118                if (o->reverse_diff) {
 119                        unsigned tmp;
 120                        const char *tmp_c;
 121                        tmp = mode1; mode1 = mode2; mode2 = tmp;
 122                        tmp_c = name1; name1 = name2; name2 = tmp_c;
 123                }
 124
 125                if (!name1)
 126                        name1 = "/dev/null";
 127                if (!name2)
 128                        name2 = "/dev/null";
 129                d1 = alloc_filespec(name1);
 130                d2 = alloc_filespec(name2);
 131                fill_filespec(d1, null_sha1, mode1);
 132                fill_filespec(d2, null_sha1, mode2);
 133
 134                diff_queue(&diff_queued_diff, d1, d2);
 135                return 0;
 136        }
 137}
 138
 139static int is_in_index(const char *path)
 140{
 141        int len = strlen(path);
 142        int pos = cache_name_pos(path, len);
 143        char c;
 144
 145        if (pos < 0)
 146                return 0;
 147        if (strncmp(active_cache[pos]->name, path, len))
 148                return 0;
 149        c = active_cache[pos]->name[len];
 150        return c == '\0' || c == '/';
 151}
 152
 153static int handle_diff_files_args(struct rev_info *revs,
 154                int argc, const char **argv, int *silent)
 155{
 156        *silent = 0;
 157
 158        /* revs->max_count == -2 means --no-index */
 159        while (1 < argc && argv[1][0] == '-') {
 160                if (!strcmp(argv[1], "--base"))
 161                        revs->max_count = 1;
 162                else if (!strcmp(argv[1], "--ours"))
 163                        revs->max_count = 2;
 164                else if (!strcmp(argv[1], "--theirs"))
 165                        revs->max_count = 3;
 166                else if (!strcmp(argv[1], "-n") ||
 167                                !strcmp(argv[1], "--no-index"))
 168                        revs->max_count = -2;
 169                else if (!strcmp(argv[1], "-q"))
 170                        *silent = 1;
 171                else
 172                        return error("invalid option: %s", argv[1]);
 173                argv++; argc--;
 174        }
 175
 176        if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
 177                /*
 178                 * If two files are specified, and at least one is untracked,
 179                 * default to no-index.
 180                 */
 181                read_cache();
 182                if (!is_in_index(revs->diffopt.paths[0]) ||
 183                                        !is_in_index(revs->diffopt.paths[1]))
 184                        revs->max_count = -2;
 185        }
 186
 187        /*
 188         * Make sure there are NO revision (i.e. pending object) parameter,
 189         * rev.max_count is reasonable (0 <= n <= 3),
 190         * there is no other revision filtering parameters.
 191         */
 192        if (revs->pending.nr || revs->max_count > 3 ||
 193            revs->min_age != -1 || revs->max_age != -1)
 194                return error("no revision allowed with diff-files");
 195
 196        if (revs->max_count == -1 &&
 197            (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
 198                revs->combine_merges = revs->dense_combined_merges = 1;
 199
 200        return 0;
 201}
 202
 203static int is_outside_repo(const char *path, int nongit, const char *prefix)
 204{
 205        int i;
 206        if (nongit || !strcmp(path, "-") || path[0] == '/')
 207                return 1;
 208        if (prefixcmp(path, "../"))
 209                return 0;
 210        if (!prefix)
 211                return 1;
 212        for (i = strlen(prefix); !prefixcmp(path, "../"); ) {
 213                while (i > 0 && prefix[i - 1] != '/')
 214                        i--;
 215                if (--i < 0)
 216                        return 1;
 217                path += 3;
 218        }
 219        return 0;
 220}
 221
 222int setup_diff_no_index(struct rev_info *revs,
 223                int argc, const char ** argv, int nongit, const char *prefix)
 224{
 225        int i;
 226        for (i = 1; i < argc; i++)
 227                if (argv[i][0] != '-')
 228                        break;
 229                else if (!strcmp(argv[i], "--")) {
 230                        i++;
 231                        break;
 232                } else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
 233                        i = argc - 3;
 234                        break;
 235                }
 236        if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
 237                                !is_outside_repo(argv[i], nongit, prefix)))
 238                return -1;
 239
 240        diff_setup(&revs->diffopt);
 241        for (i = 1; i < argc - 2; )
 242                if (!strcmp(argv[i], "--no-index"))
 243                        i++;
 244                else {
 245                        int j = diff_opt_parse(&revs->diffopt,
 246                                        argv + i, argc - i);
 247                        if (!j)
 248                                die("invalid diff option/value: %s", argv[i]);
 249                        i += j;
 250                }
 251        revs->diffopt.paths = argv + argc - 2;
 252        revs->diffopt.nr_paths = 2;
 253        revs->max_count = -2;
 254        return 0;
 255}
 256
 257int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
 258{
 259        int silent_on_removed;
 260
 261        if (handle_diff_files_args(revs, argc, argv, &silent_on_removed))
 262                return -1;
 263
 264        if (revs->max_count == -2) {
 265                if (revs->diffopt.nr_paths != 2)
 266                        return error("need two files/directories with --no-index");
 267                if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
 268                                revs->diffopt.paths[1]))
 269                        return -1;
 270                diffcore_std(&revs->diffopt);
 271                diff_flush(&revs->diffopt);
 272                /*
 273                 * The return code for --no-index imitates diff(1):
 274                 * 0 = no changes, 1 = changes, else error
 275                 */
 276                return revs->diffopt.found_changes;
 277        }
 278
 279        if (read_cache() < 0) {
 280                perror("read_cache");
 281                return -1;
 282        }
 283        return run_diff_files(revs, silent_on_removed);
 284}
 285
 286int run_diff_files(struct rev_info *revs, int silent_on_removed)
 287{
 288        int entries, i;
 289        int diff_unmerged_stage = revs->max_count;
 290
 291        if (diff_unmerged_stage < 0)
 292                diff_unmerged_stage = 2;
 293        entries = active_nr;
 294        for (i = 0; i < entries; i++) {
 295                struct stat st;
 296                unsigned int oldmode, newmode;
 297                struct cache_entry *ce = active_cache[i];
 298                int changed;
 299
 300                if (!ce_path_match(ce, revs->prune_data))
 301                        continue;
 302
 303                if (ce_stage(ce)) {
 304                        struct combine_diff_path *dpath;
 305                        int num_compare_stages = 0;
 306                        size_t path_len;
 307
 308                        path_len = ce_namelen(ce);
 309
 310                        dpath = xmalloc(combine_diff_path_size(5, path_len));
 311                        dpath->path = (char *) &(dpath->parent[5]);
 312
 313                        dpath->next = NULL;
 314                        dpath->len = path_len;
 315                        memcpy(dpath->path, ce->name, path_len);
 316                        dpath->path[path_len] = '\0';
 317                        hashclr(dpath->sha1);
 318                        memset(&(dpath->parent[0]), 0,
 319                               sizeof(struct combine_diff_parent)*5);
 320
 321                        if (lstat(ce->name, &st) < 0) {
 322                                if (errno != ENOENT && errno != ENOTDIR) {
 323                                        perror(ce->name);
 324                                        continue;
 325                                }
 326                                if (silent_on_removed)
 327                                        continue;
 328                        }
 329                        else
 330                                dpath->mode = canon_mode(st.st_mode);
 331
 332                        while (i < entries) {
 333                                struct cache_entry *nce = active_cache[i];
 334                                int stage;
 335
 336                                if (strcmp(ce->name, nce->name))
 337                                        break;
 338
 339                                /* Stage #2 (ours) is the first parent,
 340                                 * stage #3 (theirs) is the second.
 341                                 */
 342                                stage = ce_stage(nce);
 343                                if (2 <= stage) {
 344                                        int mode = ntohl(nce->ce_mode);
 345                                        num_compare_stages++;
 346                                        hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
 347                                        dpath->parent[stage-2].mode =
 348                                                canon_mode(mode);
 349                                        dpath->parent[stage-2].status =
 350                                                DIFF_STATUS_MODIFIED;
 351                                }
 352
 353                                /* diff against the proper unmerged stage */
 354                                if (stage == diff_unmerged_stage)
 355                                        ce = nce;
 356                                i++;
 357                        }
 358                        /*
 359                         * Compensate for loop update
 360                         */
 361                        i--;
 362
 363                        if (revs->combine_merges && num_compare_stages == 2) {
 364                                show_combined_diff(dpath, 2,
 365                                                   revs->dense_combined_merges,
 366                                                   revs);
 367                                free(dpath);
 368                                continue;
 369                        }
 370                        free(dpath);
 371                        dpath = NULL;
 372
 373                        /*
 374                         * Show the diff for the 'ce' if we found the one
 375                         * from the desired stage.
 376                         */
 377                        diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
 378                        if (ce_stage(ce) != diff_unmerged_stage)
 379                                continue;
 380                }
 381
 382                if (lstat(ce->name, &st) < 0) {
 383                        if (errno != ENOENT && errno != ENOTDIR) {
 384                                perror(ce->name);
 385                                continue;
 386                        }
 387                        if (silent_on_removed)
 388                                continue;
 389                        diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
 390                                       ce->sha1, ce->name, NULL);
 391                        continue;
 392                }
 393                changed = ce_match_stat(ce, &st, 0);
 394                if (!changed && !revs->diffopt.find_copies_harder)
 395                        continue;
 396                oldmode = ntohl(ce->ce_mode);
 397
 398                newmode = canon_mode(st.st_mode);
 399                if (!trust_executable_bit &&
 400                    S_ISREG(newmode) && S_ISREG(oldmode) &&
 401                    ((newmode ^ oldmode) == 0111))
 402                        newmode = oldmode;
 403                diff_change(&revs->diffopt, oldmode, newmode,
 404                            ce->sha1, (changed ? null_sha1 : ce->sha1),
 405                            ce->name, NULL);
 406
 407        }
 408        diffcore_std(&revs->diffopt);
 409        diff_flush(&revs->diffopt);
 410        return 0;
 411}
 412
 413/*
 414 * diff-index
 415 */
 416
 417/* A file entry went away or appeared */
 418static void diff_index_show_file(struct rev_info *revs,
 419                                 const char *prefix,
 420                                 struct cache_entry *ce,
 421                                 unsigned char *sha1, unsigned int mode)
 422{
 423        diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
 424                       sha1, ce->name, NULL);
 425}
 426
 427static int get_stat_data(struct cache_entry *ce,
 428                         unsigned char **sha1p,
 429                         unsigned int *modep,
 430                         int cached, int match_missing)
 431{
 432        unsigned char *sha1 = ce->sha1;
 433        unsigned int mode = ce->ce_mode;
 434
 435        if (!cached) {
 436                static unsigned char no_sha1[20];
 437                int changed;
 438                struct stat st;
 439                if (lstat(ce->name, &st) < 0) {
 440                        if (errno == ENOENT && match_missing) {
 441                                *sha1p = sha1;
 442                                *modep = mode;
 443                                return 0;
 444                        }
 445                        return -1;
 446                }
 447                changed = ce_match_stat(ce, &st, 0);
 448                if (changed) {
 449                        mode = ce_mode_from_stat(ce, st.st_mode);
 450                        sha1 = no_sha1;
 451                }
 452        }
 453
 454        *sha1p = sha1;
 455        *modep = mode;
 456        return 0;
 457}
 458
 459static void show_new_file(struct rev_info *revs,
 460                          struct cache_entry *new,
 461                          int cached, int match_missing)
 462{
 463        unsigned char *sha1;
 464        unsigned int mode;
 465
 466        /* New file in the index: it might actually be different in
 467         * the working copy.
 468         */
 469        if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
 470                return;
 471
 472        diff_index_show_file(revs, "+", new, sha1, mode);
 473}
 474
 475static int show_modified(struct rev_info *revs,
 476                         struct cache_entry *old,
 477                         struct cache_entry *new,
 478                         int report_missing,
 479                         int cached, int match_missing)
 480{
 481        unsigned int mode, oldmode;
 482        unsigned char *sha1;
 483
 484        if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
 485                if (report_missing)
 486                        diff_index_show_file(revs, "-", old,
 487                                             old->sha1, old->ce_mode);
 488                return -1;
 489        }
 490
 491        if (revs->combine_merges && !cached &&
 492            (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
 493                struct combine_diff_path *p;
 494                int pathlen = ce_namelen(new);
 495
 496                p = xmalloc(combine_diff_path_size(2, pathlen));
 497                p->path = (char *) &p->parent[2];
 498                p->next = NULL;
 499                p->len = pathlen;
 500                memcpy(p->path, new->name, pathlen);
 501                p->path[pathlen] = 0;
 502                p->mode = ntohl(mode);
 503                hashclr(p->sha1);
 504                memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
 505                p->parent[0].status = DIFF_STATUS_MODIFIED;
 506                p->parent[0].mode = ntohl(new->ce_mode);
 507                hashcpy(p->parent[0].sha1, new->sha1);
 508                p->parent[1].status = DIFF_STATUS_MODIFIED;
 509                p->parent[1].mode = ntohl(old->ce_mode);
 510                hashcpy(p->parent[1].sha1, old->sha1);
 511                show_combined_diff(p, 2, revs->dense_combined_merges, revs);
 512                free(p);
 513                return 0;
 514        }
 515
 516        oldmode = old->ce_mode;
 517        if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
 518            !revs->diffopt.find_copies_harder)
 519                return 0;
 520
 521        mode = ntohl(mode);
 522        oldmode = ntohl(oldmode);
 523
 524        diff_change(&revs->diffopt, oldmode, mode,
 525                    old->sha1, sha1, old->name, NULL);
 526        return 0;
 527}
 528
 529static int diff_cache(struct rev_info *revs,
 530                      struct cache_entry **ac, int entries,
 531                      const char **pathspec,
 532                      int cached, int match_missing)
 533{
 534        while (entries) {
 535                struct cache_entry *ce = *ac;
 536                int same = (entries > 1) && ce_same_name(ce, ac[1]);
 537
 538                if (!ce_path_match(ce, pathspec))
 539                        goto skip_entry;
 540
 541                switch (ce_stage(ce)) {
 542                case 0:
 543                        /* No stage 1 entry? That means it's a new file */
 544                        if (!same) {
 545                                show_new_file(revs, ce, cached, match_missing);
 546                                break;
 547                        }
 548                        /* Show difference between old and new */
 549                        show_modified(revs, ac[1], ce, 1,
 550                                      cached, match_missing);
 551                        break;
 552                case 1:
 553                        /* No stage 3 (merge) entry?
 554                         * That means it's been deleted.
 555                         */
 556                        if (!same) {
 557                                diff_index_show_file(revs, "-", ce,
 558                                                     ce->sha1, ce->ce_mode);
 559                                break;
 560                        }
 561                        /* We come here with ce pointing at stage 1
 562                         * (original tree) and ac[1] pointing at stage
 563                         * 3 (unmerged).  show-modified with
 564                         * report-missing set to false does not say the
 565                         * file is deleted but reports true if work
 566                         * tree does not have it, in which case we
 567                         * fall through to report the unmerged state.
 568                         * Otherwise, we show the differences between
 569                         * the original tree and the work tree.
 570                         */
 571                        if (!cached &&
 572                            !show_modified(revs, ce, ac[1], 0,
 573                                           cached, match_missing))
 574                                break;
 575                        diff_unmerge(&revs->diffopt, ce->name,
 576                                     ntohl(ce->ce_mode), ce->sha1);
 577                        break;
 578                case 3:
 579                        diff_unmerge(&revs->diffopt, ce->name,
 580                                     0, null_sha1);
 581                        break;
 582
 583                default:
 584                        die("impossible cache entry stage");
 585                }
 586
 587skip_entry:
 588                /*
 589                 * Ignore all the different stages for this file,
 590                 * we've handled the relevant cases now.
 591                 */
 592                do {
 593                        ac++;
 594                        entries--;
 595                } while (entries && ce_same_name(ce, ac[0]));
 596        }
 597        return 0;
 598}
 599
 600/*
 601 * This turns all merge entries into "stage 3". That guarantees that
 602 * when we read in the new tree (into "stage 1"), we won't lose sight
 603 * of the fact that we had unmerged entries.
 604 */
 605static void mark_merge_entries(void)
 606{
 607        int i;
 608        for (i = 0; i < active_nr; i++) {
 609                struct cache_entry *ce = active_cache[i];
 610                if (!ce_stage(ce))
 611                        continue;
 612                ce->ce_flags |= htons(CE_STAGEMASK);
 613        }
 614}
 615
 616int run_diff_index(struct rev_info *revs, int cached)
 617{
 618        int ret;
 619        struct object *ent;
 620        struct tree *tree;
 621        const char *tree_name;
 622        int match_missing = 0;
 623
 624        /* 
 625         * Backward compatibility wart - "diff-index -m" does
 626         * not mean "do not ignore merges", but totally different.
 627         */
 628        if (!revs->ignore_merges)
 629                match_missing = 1;
 630
 631        mark_merge_entries();
 632
 633        ent = revs->pending.objects[0].item;
 634        tree_name = revs->pending.objects[0].name;
 635        tree = parse_tree_indirect(ent->sha1);
 636        if (!tree)
 637                return error("bad tree object %s", tree_name);
 638        if (read_tree(tree, 1, revs->prune_data))
 639                return error("unable to read tree object %s", tree_name);
 640        ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
 641                         cached, match_missing);
 642        diffcore_std(&revs->diffopt);
 643        diff_flush(&revs->diffopt);
 644        return ret;
 645}
 646
 647int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 648{
 649        struct tree *tree;
 650        struct rev_info revs;
 651        int i;
 652        struct cache_entry **dst;
 653        struct cache_entry *last = NULL;
 654
 655        /*
 656         * This is used by git-blame to run diff-cache internally;
 657         * it potentially needs to repeatedly run this, so we will
 658         * start by removing the higher order entries the last round
 659         * left behind.
 660         */
 661        dst = active_cache;
 662        for (i = 0; i < active_nr; i++) {
 663                struct cache_entry *ce = active_cache[i];
 664                if (ce_stage(ce)) {
 665                        if (last && !strcmp(ce->name, last->name))
 666                                continue;
 667                        cache_tree_invalidate_path(active_cache_tree,
 668                                                   ce->name);
 669                        last = ce;
 670                        ce->ce_mode = 0;
 671                        ce->ce_flags &= ~htons(CE_STAGEMASK);
 672                }
 673                *dst++ = ce;
 674        }
 675        active_nr = dst - active_cache;
 676
 677        init_revisions(&revs, NULL);
 678        revs.prune_data = opt->paths;
 679        tree = parse_tree_indirect(tree_sha1);
 680        if (!tree)
 681                die("bad tree object %s", sha1_to_hex(tree_sha1));
 682        if (read_tree(tree, 1, opt->paths))
 683                return error("unable to read tree %s", sha1_to_hex(tree_sha1));
 684        return diff_cache(&revs, active_cache, active_nr, revs.prune_data,
 685                          1, 0);
 686}