builtin / diff.con commit Merge branch 'ma/pkt-line-leakfix' into maint (6da2d14)
   1/*
   2 * Builtin "git diff"
   3 *
   4 * Copyright (c) 2006 Junio C Hamano
   5 */
   6#include "cache.h"
   7#include "config.h"
   8#include "lockfile.h"
   9#include "color.h"
  10#include "commit.h"
  11#include "blob.h"
  12#include "tag.h"
  13#include "diff.h"
  14#include "diffcore.h"
  15#include "revision.h"
  16#include "log-tree.h"
  17#include "builtin.h"
  18#include "submodule.h"
  19#include "sha1-array.h"
  20
  21#define DIFF_NO_INDEX_EXPLICIT 1
  22#define DIFF_NO_INDEX_IMPLICIT 2
  23
  24static const char builtin_diff_usage[] =
  25"git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
  26
  27static const char *blob_path(struct object_array_entry *entry)
  28{
  29        return entry->path ? entry->path : entry->name;
  30}
  31
  32static void stuff_change(struct diff_options *opt,
  33                         unsigned old_mode, unsigned new_mode,
  34                         const struct object_id *old_oid,
  35                         const struct object_id *new_oid,
  36                         int old_oid_valid,
  37                         int new_oid_valid,
  38                         const char *old_path,
  39                         const char *new_path)
  40{
  41        struct diff_filespec *one, *two;
  42
  43        if (!is_null_oid(old_oid) && !is_null_oid(new_oid) &&
  44            !oidcmp(old_oid, new_oid) && (old_mode == new_mode))
  45                return;
  46
  47        if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
  48                SWAP(old_mode, new_mode);
  49                SWAP(old_oid, new_oid);
  50                SWAP(old_path, new_path);
  51        }
  52
  53        if (opt->prefix &&
  54            (strncmp(old_path, opt->prefix, opt->prefix_length) ||
  55             strncmp(new_path, opt->prefix, opt->prefix_length)))
  56                return;
  57
  58        one = alloc_filespec(old_path);
  59        two = alloc_filespec(new_path);
  60        fill_filespec(one, old_oid, old_oid_valid, old_mode);
  61        fill_filespec(two, new_oid, new_oid_valid, new_mode);
  62
  63        diff_queue(&diff_queued_diff, one, two);
  64}
  65
  66static int builtin_diff_b_f(struct rev_info *revs,
  67                            int argc, const char **argv,
  68                            struct object_array_entry **blob)
  69{
  70        /* Blob vs file in the working tree*/
  71        struct stat st;
  72        const char *path;
  73
  74        if (argc > 1)
  75                usage(builtin_diff_usage);
  76
  77        GUARD_PATHSPEC(&revs->prune_data, PATHSPEC_FROMTOP | PATHSPEC_LITERAL);
  78        path = revs->prune_data.items[0].match;
  79
  80        if (lstat(path, &st))
  81                die_errno(_("failed to stat '%s'"), path);
  82        if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
  83                die(_("'%s': not a regular file or symlink"), path);
  84
  85        diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
  86
  87        if (blob[0]->mode == S_IFINVALID)
  88                blob[0]->mode = canon_mode(st.st_mode);
  89
  90        stuff_change(&revs->diffopt,
  91                     blob[0]->mode, canon_mode(st.st_mode),
  92                     &blob[0]->item->oid, &null_oid,
  93                     1, 0,
  94                     blob[0]->path ? blob[0]->path : path,
  95                     path);
  96        diffcore_std(&revs->diffopt);
  97        diff_flush(&revs->diffopt);
  98        return 0;
  99}
 100
 101static int builtin_diff_blobs(struct rev_info *revs,
 102                              int argc, const char **argv,
 103                              struct object_array_entry **blob)
 104{
 105        unsigned mode = canon_mode(S_IFREG | 0644);
 106
 107        if (argc > 1)
 108                usage(builtin_diff_usage);
 109
 110        if (blob[0]->mode == S_IFINVALID)
 111                blob[0]->mode = mode;
 112
 113        if (blob[1]->mode == S_IFINVALID)
 114                blob[1]->mode = mode;
 115
 116        stuff_change(&revs->diffopt,
 117                     blob[0]->mode, blob[1]->mode,
 118                     &blob[0]->item->oid, &blob[1]->item->oid,
 119                     1, 1,
 120                     blob_path(blob[0]), blob_path(blob[1]));
 121        diffcore_std(&revs->diffopt);
 122        diff_flush(&revs->diffopt);
 123        return 0;
 124}
 125
 126static int builtin_diff_index(struct rev_info *revs,
 127                              int argc, const char **argv)
 128{
 129        int cached = 0;
 130        while (1 < argc) {
 131                const char *arg = argv[1];
 132                if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
 133                        cached = 1;
 134                else
 135                        usage(builtin_diff_usage);
 136                argv++; argc--;
 137        }
 138        /*
 139         * Make sure there is one revision (i.e. pending object),
 140         * and there is no revision filtering parameters.
 141         */
 142        if (revs->pending.nr != 1 ||
 143            revs->max_count != -1 || revs->min_age != -1 ||
 144            revs->max_age != -1)
 145                usage(builtin_diff_usage);
 146        if (!cached) {
 147                setup_work_tree();
 148                if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
 149                        perror("read_cache_preload");
 150                        return -1;
 151                }
 152        } else if (read_cache() < 0) {
 153                perror("read_cache");
 154                return -1;
 155        }
 156        return run_diff_index(revs, cached);
 157}
 158
 159static int builtin_diff_tree(struct rev_info *revs,
 160                             int argc, const char **argv,
 161                             struct object_array_entry *ent0,
 162                             struct object_array_entry *ent1)
 163{
 164        const struct object_id *(oid[2]);
 165        int swap = 0;
 166
 167        if (argc > 1)
 168                usage(builtin_diff_usage);
 169
 170        /*
 171         * We saw two trees, ent0 and ent1.  If ent1 is uninteresting,
 172         * swap them.
 173         */
 174        if (ent1->item->flags & UNINTERESTING)
 175                swap = 1;
 176        oid[swap] = &ent0->item->oid;
 177        oid[1 - swap] = &ent1->item->oid;
 178        diff_tree_oid(oid[0], oid[1], "", &revs->diffopt);
 179        log_tree_diff_flush(revs);
 180        return 0;
 181}
 182
 183static int builtin_diff_combined(struct rev_info *revs,
 184                                 int argc, const char **argv,
 185                                 struct object_array_entry *ent,
 186                                 int ents)
 187{
 188        struct oid_array parents = OID_ARRAY_INIT;
 189        int i;
 190
 191        if (argc > 1)
 192                usage(builtin_diff_usage);
 193
 194        if (!revs->dense_combined_merges && !revs->combine_merges)
 195                revs->dense_combined_merges = revs->combine_merges = 1;
 196        for (i = 1; i < ents; i++)
 197                oid_array_append(&parents, &ent[i].item->oid);
 198        diff_tree_combined(&ent[0].item->oid, &parents,
 199                           revs->dense_combined_merges, revs);
 200        oid_array_clear(&parents);
 201        return 0;
 202}
 203
 204static void refresh_index_quietly(void)
 205{
 206        struct lock_file *lock_file;
 207        int fd;
 208
 209        lock_file = xcalloc(1, sizeof(struct lock_file));
 210        fd = hold_locked_index(lock_file, 0);
 211        if (fd < 0)
 212                return;
 213        discard_cache();
 214        read_cache();
 215        refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
 216        update_index_if_able(&the_index, lock_file);
 217}
 218
 219static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
 220{
 221        unsigned int options = 0;
 222
 223        while (1 < argc && argv[1][0] == '-') {
 224                if (!strcmp(argv[1], "--base"))
 225                        revs->max_count = 1;
 226                else if (!strcmp(argv[1], "--ours"))
 227                        revs->max_count = 2;
 228                else if (!strcmp(argv[1], "--theirs"))
 229                        revs->max_count = 3;
 230                else if (!strcmp(argv[1], "-q"))
 231                        options |= DIFF_SILENT_ON_REMOVED;
 232                else if (!strcmp(argv[1], "-h"))
 233                        usage(builtin_diff_usage);
 234                else
 235                        return error(_("invalid option: %s"), argv[1]);
 236                argv++; argc--;
 237        }
 238
 239        /*
 240         * "diff --base" should not combine merges because it was not
 241         * asked to.  "diff -c" should not densify (if the user wants
 242         * dense one, --cc can be explicitly asked for, or just rely
 243         * on the default).
 244         */
 245        if (revs->max_count == -1 && !revs->combine_merges &&
 246            (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
 247                revs->combine_merges = revs->dense_combined_merges = 1;
 248
 249        setup_work_tree();
 250        if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
 251                perror("read_cache_preload");
 252                return -1;
 253        }
 254        return run_diff_files(revs, options);
 255}
 256
 257int cmd_diff(int argc, const char **argv, const char *prefix)
 258{
 259        int i;
 260        struct rev_info rev;
 261        struct object_array ent = OBJECT_ARRAY_INIT;
 262        int blobs = 0, paths = 0;
 263        struct object_array_entry *blob[2];
 264        int nongit = 0, no_index = 0;
 265        int result = 0;
 266
 267        /*
 268         * We could get N tree-ish in the rev.pending_objects list.
 269         * Also there could be M blobs there, and P pathspecs.
 270         *
 271         * N=0, M=0:
 272         *      cache vs files (diff-files)
 273         * N=0, M=2:
 274         *      compare two random blobs.  P must be zero.
 275         * N=0, M=1, P=1:
 276         *      compare a blob with a working tree file.
 277         *
 278         * N=1, M=0:
 279         *      tree vs cache (diff-index --cached)
 280         *
 281         * N=2, M=0:
 282         *      tree vs tree (diff-tree)
 283         *
 284         * N=0, M=0, P=2:
 285         *      compare two filesystem entities (aka --no-index).
 286         *
 287         * Other cases are errors.
 288         */
 289
 290        /* Were we asked to do --no-index explicitly? */
 291        for (i = 1; i < argc; i++) {
 292                if (!strcmp(argv[i], "--")) {
 293                        i++;
 294                        break;
 295                }
 296                if (!strcmp(argv[i], "--no-index"))
 297                        no_index = DIFF_NO_INDEX_EXPLICIT;
 298                if (argv[i][0] != '-')
 299                        break;
 300        }
 301
 302        prefix = setup_git_directory_gently(&nongit);
 303
 304        if (!no_index) {
 305                /*
 306                 * Treat git diff with at least one path outside of the
 307                 * repo the same as if the command would have been executed
 308                 * outside of a git repository.  In this case it behaves
 309                 * the same way as "git diff --no-index <a> <b>", which acts
 310                 * as a colourful "diff" replacement.
 311                 */
 312                if (nongit || ((argc == i + 2) &&
 313                               (!path_inside_repo(prefix, argv[i]) ||
 314                                !path_inside_repo(prefix, argv[i + 1]))))
 315                        no_index = DIFF_NO_INDEX_IMPLICIT;
 316        }
 317
 318        if (!no_index)
 319                gitmodules_config();
 320        init_diff_ui_defaults();
 321        git_config(git_diff_ui_config, NULL);
 322        precompose_argv(argc, argv);
 323
 324        init_revisions(&rev, prefix);
 325
 326        if (no_index && argc != i + 2) {
 327                if (no_index == DIFF_NO_INDEX_IMPLICIT) {
 328                        /*
 329                         * There was no --no-index and there were not two
 330                         * paths. It is possible that the user intended
 331                         * to do an inside-repository operation.
 332                         */
 333                        fprintf(stderr, "Not a git repository\n");
 334                        fprintf(stderr,
 335                                "To compare two paths outside a working tree:\n");
 336                }
 337                /* Give the usage message for non-repository usage and exit. */
 338                usagef("git diff %s <path> <path>",
 339                       no_index == DIFF_NO_INDEX_EXPLICIT ?
 340                       "--no-index" : "[--no-index]");
 341
 342        }
 343        if (no_index)
 344                /* If this is a no-index diff, just run it and exit there. */
 345                diff_no_index(&rev, argc, argv);
 346
 347        /* Otherwise, we are doing the usual "git" diff */
 348        rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
 349
 350        /* Scale to real terminal size and respect statGraphWidth config */
 351        rev.diffopt.stat_width = -1;
 352        rev.diffopt.stat_graph_width = -1;
 353
 354        /* Default to let external and textconv be used */
 355        DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
 356        DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
 357
 358        if (nongit)
 359                die(_("Not a git repository"));
 360        argc = setup_revisions(argc, argv, &rev, NULL);
 361        if (!rev.diffopt.output_format) {
 362                rev.diffopt.output_format = DIFF_FORMAT_PATCH;
 363                diff_setup_done(&rev.diffopt);
 364        }
 365
 366        DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
 367
 368        setup_diff_pager(&rev.diffopt);
 369
 370        /*
 371         * Do we have --cached and not have a pending object, then
 372         * default to HEAD by hand.  Eek.
 373         */
 374        if (!rev.pending.nr) {
 375                int i;
 376                for (i = 1; i < argc; i++) {
 377                        const char *arg = argv[i];
 378                        if (!strcmp(arg, "--"))
 379                                break;
 380                        else if (!strcmp(arg, "--cached") ||
 381                                 !strcmp(arg, "--staged")) {
 382                                add_head_to_pending(&rev);
 383                                if (!rev.pending.nr) {
 384                                        struct tree *tree;
 385                                        tree = lookup_tree(&empty_tree_oid);
 386                                        add_pending_object(&rev, &tree->object, "HEAD");
 387                                }
 388                                break;
 389                        }
 390                }
 391        }
 392
 393        for (i = 0; i < rev.pending.nr; i++) {
 394                struct object_array_entry *entry = &rev.pending.objects[i];
 395                struct object *obj = entry->item;
 396                const char *name = entry->name;
 397                int flags = (obj->flags & UNINTERESTING);
 398                if (!obj->parsed)
 399                        obj = parse_object(&obj->oid);
 400                obj = deref_tag(obj, NULL, 0);
 401                if (!obj)
 402                        die(_("invalid object '%s' given."), name);
 403                if (obj->type == OBJ_COMMIT)
 404                        obj = &((struct commit *)obj)->tree->object;
 405
 406                if (obj->type == OBJ_TREE) {
 407                        obj->flags |= flags;
 408                        add_object_array(obj, name, &ent);
 409                } else if (obj->type == OBJ_BLOB) {
 410                        if (2 <= blobs)
 411                                die(_("more than two blobs given: '%s'"), name);
 412                        blob[blobs] = entry;
 413                        blobs++;
 414
 415                } else {
 416                        die(_("unhandled object '%s' given."), name);
 417                }
 418        }
 419        if (rev.prune_data.nr)
 420                paths += rev.prune_data.nr;
 421
 422        /*
 423         * Now, do the arguments look reasonable?
 424         */
 425        if (!ent.nr) {
 426                switch (blobs) {
 427                case 0:
 428                        result = builtin_diff_files(&rev, argc, argv);
 429                        break;
 430                case 1:
 431                        if (paths != 1)
 432                                usage(builtin_diff_usage);
 433                        result = builtin_diff_b_f(&rev, argc, argv, blob);
 434                        break;
 435                case 2:
 436                        if (paths)
 437                                usage(builtin_diff_usage);
 438                        result = builtin_diff_blobs(&rev, argc, argv, blob);
 439                        break;
 440                default:
 441                        usage(builtin_diff_usage);
 442                }
 443        }
 444        else if (blobs)
 445                usage(builtin_diff_usage);
 446        else if (ent.nr == 1)
 447                result = builtin_diff_index(&rev, argc, argv);
 448        else if (ent.nr == 2)
 449                result = builtin_diff_tree(&rev, argc, argv,
 450                                           &ent.objects[0], &ent.objects[1]);
 451        else if (ent.objects[0].item->flags & UNINTERESTING) {
 452                /*
 453                 * diff A...B where there is at least one merge base
 454                 * between A and B.  We have ent.objects[0] ==
 455                 * merge-base, ent.objects[ents-2] == A, and
 456                 * ent.objects[ents-1] == B.  Show diff between the
 457                 * base and B.  Note that we pick one merge base at
 458                 * random if there are more than one.
 459                 */
 460                result = builtin_diff_tree(&rev, argc, argv,
 461                                           &ent.objects[0],
 462                                           &ent.objects[ent.nr-1]);
 463        } else
 464                result = builtin_diff_combined(&rev, argc, argv,
 465                                               ent.objects, ent.nr);
 466        result = diff_result_code(&rev.diffopt, result);
 467        if (1 < rev.diffopt.skip_stat_unmatch)
 468                refresh_index_quietly();
 469        return result;
 470}