c8d93ff106d88cd7c11a8b246d0d469301a2ffab
   1#include "cache.h"
   2#include "tag.h"
   3#include "blob.h"
   4#include "tree.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "refs.h"
   8#include "revision.h"
   9
  10static char *path_name(struct name_path *path, const char *name)
  11{
  12        struct name_path *p;
  13        char *n, *m;
  14        int nlen = strlen(name);
  15        int len = nlen + 1;
  16
  17        for (p = path; p; p = p->up) {
  18                if (p->elem_len)
  19                        len += p->elem_len + 1;
  20        }
  21        n = xmalloc(len);
  22        m = n + len - (nlen + 1);
  23        strcpy(m, name);
  24        for (p = path; p; p = p->up) {
  25                if (p->elem_len) {
  26                        m -= p->elem_len + 1;
  27                        memcpy(m, p->elem, p->elem_len);
  28                        m[p->elem_len] = '/';
  29                }
  30        }
  31        return n;
  32}
  33
  34struct object_list **add_object(struct object *obj,
  35                                       struct object_list **p,
  36                                       struct name_path *path,
  37                                       const char *name)
  38{
  39        struct object_list *entry = xmalloc(sizeof(*entry));
  40        entry->item = obj;
  41        entry->next = *p;
  42        entry->name = path_name(path, name);
  43        *p = entry;
  44        return &entry->next;
  45}
  46
  47static void mark_blob_uninteresting(struct blob *blob)
  48{
  49        if (blob->object.flags & UNINTERESTING)
  50                return;
  51        blob->object.flags |= UNINTERESTING;
  52}
  53
  54void mark_tree_uninteresting(struct tree *tree)
  55{
  56        struct object *obj = &tree->object;
  57        struct tree_entry_list *entry;
  58
  59        if (obj->flags & UNINTERESTING)
  60                return;
  61        obj->flags |= UNINTERESTING;
  62        if (!has_sha1_file(obj->sha1))
  63                return;
  64        if (parse_tree(tree) < 0)
  65                die("bad tree %s", sha1_to_hex(obj->sha1));
  66        entry = tree->entries;
  67        tree->entries = NULL;
  68        while (entry) {
  69                struct tree_entry_list *next = entry->next;
  70                if (entry->directory)
  71                        mark_tree_uninteresting(entry->item.tree);
  72                else
  73                        mark_blob_uninteresting(entry->item.blob);
  74                free(entry);
  75                entry = next;
  76        }
  77}
  78
  79void mark_parents_uninteresting(struct commit *commit)
  80{
  81        struct commit_list *parents = commit->parents;
  82
  83        while (parents) {
  84                struct commit *commit = parents->item;
  85                if (!(commit->object.flags & UNINTERESTING)) {
  86                        commit->object.flags |= UNINTERESTING;
  87
  88                        /*
  89                         * Normally we haven't parsed the parent
  90                         * yet, so we won't have a parent of a parent
  91                         * here. However, it may turn out that we've
  92                         * reached this commit some other way (where it
  93                         * wasn't uninteresting), in which case we need
  94                         * to mark its parents recursively too..
  95                         */
  96                        if (commit->parents)
  97                                mark_parents_uninteresting(commit);
  98                }
  99
 100                /*
 101                 * A missing commit is ok iff its parent is marked
 102                 * uninteresting.
 103                 *
 104                 * We just mark such a thing parsed, so that when
 105                 * it is popped next time around, we won't be trying
 106                 * to parse it and get an error.
 107                 */
 108                if (!has_sha1_file(commit->object.sha1))
 109                        commit->object.parsed = 1;
 110                parents = parents->next;
 111        }
 112}
 113
 114static void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 115{
 116        add_object(obj, &revs->pending_objects, NULL, name);
 117}
 118
 119static struct commit *get_commit_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 120{
 121        struct object *object;
 122
 123        object = parse_object(sha1);
 124        if (!object)
 125                die("bad object %s", name);
 126
 127        /*
 128         * Tag object? Look what it points to..
 129         */
 130        while (object->type == tag_type) {
 131                struct tag *tag = (struct tag *) object;
 132                object->flags |= flags;
 133                if (revs->tag_objects && !(object->flags & UNINTERESTING))
 134                        add_pending_object(revs, object, tag->tag);
 135                object = parse_object(tag->tagged->sha1);
 136                if (!object)
 137                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 138        }
 139
 140        /*
 141         * Commit object? Just return it, we'll do all the complex
 142         * reachability crud.
 143         */
 144        if (object->type == commit_type) {
 145                struct commit *commit = (struct commit *)object;
 146                object->flags |= flags;
 147                if (parse_commit(commit) < 0)
 148                        die("unable to parse commit %s", name);
 149                if (flags & UNINTERESTING) {
 150                        mark_parents_uninteresting(commit);
 151                        revs->limited = 1;
 152                }
 153                return commit;
 154        }
 155
 156        /*
 157         * Tree object? Either mark it uniniteresting, or add it
 158         * to the list of objects to look at later..
 159         */
 160        if (object->type == tree_type) {
 161                struct tree *tree = (struct tree *)object;
 162                if (!revs->tree_objects)
 163                        return NULL;
 164                if (flags & UNINTERESTING) {
 165                        mark_tree_uninteresting(tree);
 166                        return NULL;
 167                }
 168                add_pending_object(revs, object, "");
 169                return NULL;
 170        }
 171
 172        /*
 173         * Blob object? You know the drill by now..
 174         */
 175        if (object->type == blob_type) {
 176                struct blob *blob = (struct blob *)object;
 177                if (!revs->blob_objects)
 178                        return NULL;
 179                if (flags & UNINTERESTING) {
 180                        mark_blob_uninteresting(blob);
 181                        return NULL;
 182                }
 183                add_pending_object(revs, object, "");
 184                return NULL;
 185        }
 186        die("%s is unknown object", name);
 187}
 188
 189static int everybody_uninteresting(struct commit_list *orig)
 190{
 191        struct commit_list *list = orig;
 192        while (list) {
 193                struct commit *commit = list->item;
 194                list = list->next;
 195                if (commit->object.flags & UNINTERESTING)
 196                        continue;
 197                return 0;
 198        }
 199        return 1;
 200}
 201
 202#define TREE_SAME       0
 203#define TREE_NEW        1
 204#define TREE_DIFFERENT  2
 205static int tree_difference = TREE_SAME;
 206
 207static void file_add_remove(struct diff_options *options,
 208                    int addremove, unsigned mode,
 209                    const unsigned char *sha1,
 210                    const char *base, const char *path)
 211{
 212        int diff = TREE_DIFFERENT;
 213
 214        /*
 215         * Is it an add of a new file? It means that
 216         * the old tree didn't have it at all, so we
 217         * will turn "TREE_SAME" -> "TREE_NEW", but
 218         * leave any "TREE_DIFFERENT" alone (and if
 219         * it already was "TREE_NEW", we'll keep it
 220         * "TREE_NEW" of course).
 221         */
 222        if (addremove == '+') {
 223                diff = tree_difference;
 224                if (diff != TREE_SAME)
 225                        return;
 226                diff = TREE_NEW;
 227        }
 228        tree_difference = diff;
 229}
 230
 231static void file_change(struct diff_options *options,
 232                 unsigned old_mode, unsigned new_mode,
 233                 const unsigned char *old_sha1,
 234                 const unsigned char *new_sha1,
 235                 const char *base, const char *path)
 236{
 237        tree_difference = TREE_DIFFERENT;
 238}
 239
 240static struct diff_options diff_opt = {
 241        .recursive = 1,
 242        .add_remove = file_add_remove,
 243        .change = file_change,
 244};
 245
 246static int compare_tree(struct tree *t1, struct tree *t2)
 247{
 248        if (!t1)
 249                return TREE_NEW;
 250        if (!t2)
 251                return TREE_DIFFERENT;
 252        tree_difference = TREE_SAME;
 253        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 254                return TREE_DIFFERENT;
 255        return tree_difference;
 256}
 257
 258static int same_tree_as_empty(struct tree *t1)
 259{
 260        int retval;
 261        void *tree;
 262        struct tree_desc empty, real;
 263
 264        if (!t1)
 265                return 0;
 266
 267        tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 268        if (!tree)
 269                return 0;
 270        real.buf = tree;
 271
 272        empty.buf = "";
 273        empty.size = 0;
 274
 275        tree_difference = 0;
 276        retval = diff_tree(&empty, &real, "", &diff_opt);
 277        free(tree);
 278
 279        return retval >= 0 && !tree_difference;
 280}
 281
 282static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 283{
 284        struct commit_list **pp, *parent;
 285        int tree_changed = 0;
 286
 287        if (!commit->tree)
 288                return;
 289
 290        if (!commit->parents) {
 291                if (!same_tree_as_empty(commit->tree))
 292                        commit->object.flags |= TREECHANGE;
 293                return;
 294        }
 295
 296        pp = &commit->parents;
 297        while ((parent = *pp) != NULL) {
 298                struct commit *p = parent->item;
 299
 300                parse_commit(p);
 301                switch (compare_tree(p->tree, commit->tree)) {
 302                case TREE_SAME:
 303                        if (p->object.flags & UNINTERESTING) {
 304                                /* Even if a merge with an uninteresting
 305                                 * side branch brought the entire change
 306                                 * we are interested in, we do not want
 307                                 * to lose the other branches of this
 308                                 * merge, so we just keep going.
 309                                 */
 310                                pp = &parent->next;
 311                                continue;
 312                        }
 313                        parent->next = NULL;
 314                        commit->parents = parent;
 315                        return;
 316
 317                case TREE_NEW:
 318                        if (revs->remove_empty_trees && same_tree_as_empty(p->tree)) {
 319                                *pp = parent->next;
 320                                continue;
 321                        }
 322                /* fallthrough */
 323                case TREE_DIFFERENT:
 324                        tree_changed = 1;
 325                        pp = &parent->next;
 326                        continue;
 327                }
 328                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 329        }
 330        if (tree_changed)
 331                commit->object.flags |= TREECHANGE;
 332}
 333
 334static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 335{
 336        struct commit_list *parent = commit->parents;
 337
 338        /*
 339         * If the commit is uninteresting, don't try to
 340         * prune parents - we want the maximal uninteresting
 341         * set.
 342         *
 343         * Normally we haven't parsed the parent
 344         * yet, so we won't have a parent of a parent
 345         * here. However, it may turn out that we've
 346         * reached this commit some other way (where it
 347         * wasn't uninteresting), in which case we need
 348         * to mark its parents recursively too..
 349         */
 350        if (commit->object.flags & UNINTERESTING) {
 351                while (parent) {
 352                        struct commit *p = parent->item;
 353                        parent = parent->next;
 354                        parse_commit(p);
 355                        p->object.flags |= UNINTERESTING;
 356                        if (p->parents)
 357                                mark_parents_uninteresting(p);
 358                        if (p->object.flags & SEEN)
 359                                continue;
 360                        p->object.flags |= SEEN;
 361                        insert_by_date(p, list);
 362                }
 363                return;
 364        }
 365
 366        /*
 367         * Ok, the commit wasn't uninteresting. Try to
 368         * simplify the commit history and find the parent
 369         * that has no differences in the path set if one exists.
 370         */
 371        if (revs->paths)
 372                try_to_simplify_commit(revs, commit);
 373
 374        parent = commit->parents;
 375        while (parent) {
 376                struct commit *p = parent->item;
 377
 378                parent = parent->next;
 379
 380                parse_commit(p);
 381                if (p->object.flags & SEEN)
 382                        continue;
 383                p->object.flags |= SEEN;
 384                insert_by_date(p, list);
 385        }
 386}
 387
 388static void limit_list(struct rev_info *revs)
 389{
 390        struct commit_list *list = revs->commits;
 391        struct commit_list *newlist = NULL;
 392        struct commit_list **p = &newlist;
 393
 394        if (revs->paths)
 395                diff_tree_setup_paths(revs->paths);
 396
 397        while (list) {
 398                struct commit_list *entry = list;
 399                struct commit *commit = list->item;
 400                struct object *obj = &commit->object;
 401
 402                list = list->next;
 403                free(entry);
 404
 405                if (revs->max_age != -1 && (commit->date < revs->max_age))
 406                        obj->flags |= UNINTERESTING;
 407                if (revs->unpacked && has_sha1_pack(obj->sha1))
 408                        obj->flags |= UNINTERESTING;
 409                add_parents_to_list(revs, commit, &list);
 410                if (obj->flags & UNINTERESTING) {
 411                        mark_parents_uninteresting(commit);
 412                        if (everybody_uninteresting(list))
 413                                break;
 414                        continue;
 415                }
 416                if (revs->min_age != -1 && (commit->date > revs->min_age))
 417                        continue;
 418                p = &commit_list_insert(commit, p)->next;
 419        }
 420        revs->commits = newlist;
 421}
 422
 423static void add_one_commit(struct commit *commit, struct rev_info *revs)
 424{
 425        if (!commit || (commit->object.flags & SEEN))
 426                return;
 427        commit->object.flags |= SEEN;
 428        commit_list_insert(commit, &revs->commits);
 429}
 430
 431static int all_flags;
 432static struct rev_info *all_revs;
 433
 434static int handle_one_ref(const char *path, const unsigned char *sha1)
 435{
 436        struct commit *commit = get_commit_reference(all_revs, path, sha1, all_flags);
 437        add_one_commit(commit, all_revs);
 438        return 0;
 439}
 440
 441static void handle_all(struct rev_info *revs, unsigned flags)
 442{
 443        all_revs = revs;
 444        all_flags = flags;
 445        for_each_ref(handle_one_ref);
 446}
 447
 448/*
 449 * Parse revision information, filling in the "rev_info" structure,
 450 * and removing the used arguments from the argument list.
 451 *
 452 * Returns the number of arguments left that weren't recognized
 453 * (which are also moved to the head of the argument list)
 454 */
 455int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 456{
 457        int i, flags, seen_dashdash;
 458        const char **unrecognized = argv + 1;
 459        int left = 1;
 460
 461        memset(revs, 0, sizeof(*revs));
 462        revs->lifo = 1;
 463        revs->dense = 1;
 464        revs->prefix = setup_git_directory();
 465        revs->max_age = -1;
 466        revs->min_age = -1;
 467        revs->max_count = -1;
 468
 469        /* First, search for "--" */
 470        seen_dashdash = 0;
 471        for (i = 1; i < argc; i++) {
 472                const char *arg = argv[i];
 473                if (strcmp(arg, "--"))
 474                        continue;
 475                argv[i] = NULL;
 476                argc = i;
 477                revs->paths = get_pathspec(revs->prefix, argv + i + 1);
 478                seen_dashdash = 1;
 479                break;
 480        }
 481
 482        flags = 0;
 483        for (i = 1; i < argc; i++) {
 484                struct commit *commit;
 485                const char *arg = argv[i];
 486                unsigned char sha1[20];
 487                char *dotdot;
 488                int local_flags;
 489
 490                if (*arg == '-') {
 491                        if (!strncmp(arg, "--max-count=", 12)) {
 492                                revs->max_count = atoi(arg + 12);
 493                                continue;
 494                        }
 495                        /* accept -<digit>, like traditilnal "head" */
 496                        if ((*arg == '-') && isdigit(arg[1])) {
 497                                revs->max_count = atoi(arg + 1);
 498                                continue;
 499                        }
 500                        if (!strcmp(arg, "-n")) {
 501                                if (argc <= i + 1)
 502                                        die("-n requires an argument");
 503                                revs->max_count = atoi(argv[++i]);
 504                                continue;
 505                        }
 506                        if (!strncmp(arg,"-n",2)) {
 507                                revs->max_count = atoi(arg + 2);
 508                                continue;
 509                        }
 510                        if (!strncmp(arg, "--max-age=", 10)) {
 511                                revs->max_age = atoi(arg + 10);
 512                                revs->limited = 1;
 513                                continue;
 514                        }
 515                        if (!strncmp(arg, "--min-age=", 10)) {
 516                                revs->min_age = atoi(arg + 10);
 517                                revs->limited = 1;
 518                                continue;
 519                        }
 520                        if (!strncmp(arg, "--since=", 8)) {
 521                                revs->max_age = approxidate(arg + 8);
 522                                revs->limited = 1;
 523                                continue;
 524                        }
 525                        if (!strncmp(arg, "--after=", 8)) {
 526                                revs->max_age = approxidate(arg + 8);
 527                                revs->limited = 1;
 528                                continue;
 529                        }
 530                        if (!strncmp(arg, "--before=", 9)) {
 531                                revs->min_age = approxidate(arg + 9);
 532                                revs->limited = 1;
 533                                continue;
 534                        }
 535                        if (!strncmp(arg, "--until=", 8)) {
 536                                revs->min_age = approxidate(arg + 8);
 537                                revs->limited = 1;
 538                                continue;
 539                        }
 540                        if (!strcmp(arg, "--all")) {
 541                                handle_all(revs, flags);
 542                                continue;
 543                        }
 544                        if (!strcmp(arg, "--not")) {
 545                                flags ^= UNINTERESTING;
 546                                continue;
 547                        }
 548                        if (!strcmp(arg, "--default")) {
 549                                if (++i >= argc)
 550                                        die("bad --default argument");
 551                                def = argv[i];
 552                                continue;
 553                        }
 554                        if (!strcmp(arg, "--topo-order")) {
 555                                revs->topo_order = 1;
 556                                revs->limited = 1;
 557                                continue;
 558                        }
 559                        if (!strcmp(arg, "--date-order")) {
 560                                revs->lifo = 0;
 561                                revs->topo_order = 1;
 562                                revs->limited = 1;
 563                                continue;
 564                        }
 565                        if (!strcmp(arg, "--dense")) {
 566                                revs->dense = 1;
 567                                continue;
 568                        }
 569                        if (!strcmp(arg, "--sparse")) {
 570                                revs->dense = 0;
 571                                continue;
 572                        }
 573                        if (!strcmp(arg, "--remove-empty")) {
 574                                revs->remove_empty_trees = 1;
 575                                continue;
 576                        }
 577                        if (!strncmp(arg, "--no-merges", 11)) {
 578                                revs->no_merges = 1;
 579                                continue;
 580                        }
 581                        if (!strcmp(arg, "--objects")) {
 582                                revs->tag_objects = 1;
 583                                revs->tree_objects = 1;
 584                                revs->blob_objects = 1;
 585                                continue;
 586                        }
 587                        if (!strcmp(arg, "--objects-edge")) {
 588                                revs->tag_objects = 1;
 589                                revs->tree_objects = 1;
 590                                revs->blob_objects = 1;
 591                                revs->edge_hint = 1;
 592                                continue;
 593                        }
 594                        if (!strcmp(arg, "--unpacked")) {
 595                                revs->unpacked = 1;
 596                                revs->limited = 1;
 597                                continue;
 598                        }
 599                        *unrecognized++ = arg;
 600                        left++;
 601                        continue;
 602                }
 603                dotdot = strstr(arg, "..");
 604                if (dotdot) {
 605                        unsigned char from_sha1[20];
 606                        char *next = dotdot + 2;
 607                        *dotdot = 0;
 608                        if (!*next)
 609                                next = "HEAD";
 610                        if (!get_sha1(arg, from_sha1) && !get_sha1(next, sha1)) {
 611                                struct commit *exclude;
 612                                struct commit *include;
 613
 614                                exclude = get_commit_reference(revs, arg, from_sha1, flags ^ UNINTERESTING);
 615                                include = get_commit_reference(revs, next, sha1, flags);
 616                                if (!exclude || !include)
 617                                        die("Invalid revision range %s..%s", arg, next);
 618                                add_one_commit(exclude, revs);
 619                                add_one_commit(include, revs);
 620                                continue;
 621                        }
 622                        *dotdot = '.';
 623                }
 624                local_flags = 0;
 625                if (*arg == '^') {
 626                        local_flags = UNINTERESTING;
 627                        arg++;
 628                }
 629                if (get_sha1(arg, sha1) < 0) {
 630                        struct stat st;
 631                        int j;
 632
 633                        if (seen_dashdash || local_flags)
 634                                die("bad revision '%s'", arg);
 635
 636                        /* If we didn't have a "--", all filenames must exist */
 637                        for (j = i; j < argc; j++) {
 638                                if (lstat(argv[j], &st) < 0)
 639                                        die("'%s': %s", arg, strerror(errno));
 640                        }
 641                        revs->paths = get_pathspec(revs->prefix, argv + i);
 642                        break;
 643                }
 644                commit = get_commit_reference(revs, arg, sha1, flags ^ local_flags);
 645                add_one_commit(commit, revs);
 646        }
 647        if (def && !revs->commits) {
 648                unsigned char sha1[20];
 649                struct commit *commit;
 650                if (get_sha1(def, sha1) < 0)
 651                        die("bad default revision '%s'", def);
 652                commit = get_commit_reference(revs, def, sha1, 0);
 653                add_one_commit(commit, revs);
 654        }
 655        if (revs->paths)
 656                revs->limited = 1;
 657        return left;
 658}
 659
 660void prepare_revision_walk(struct rev_info *revs)
 661{
 662        sort_by_date(&revs->commits);
 663        if (revs->limited)
 664                limit_list(revs);
 665        if (revs->topo_order)
 666                sort_in_topological_order(&revs->commits, revs->lifo);
 667}
 668
 669static int rewrite_one(struct commit **pp)
 670{
 671        for (;;) {
 672                struct commit *p = *pp;
 673                if (p->object.flags & (TREECHANGE | UNINTERESTING))
 674                        return 0;
 675                if (!p->parents)
 676                        return -1;
 677                *pp = p->parents->item;
 678        }
 679}
 680
 681static void rewrite_parents(struct commit *commit)
 682{
 683        struct commit_list **pp = &commit->parents;
 684        while (*pp) {
 685                struct commit_list *parent = *pp;
 686                if (rewrite_one(&parent->item) < 0) {
 687                        *pp = parent->next;
 688                        continue;
 689                }
 690                pp = &parent->next;
 691        }
 692}
 693
 694struct commit *get_revision(struct rev_info *revs)
 695{
 696        struct commit_list *list = revs->commits;
 697
 698        if (!list)
 699                return NULL;
 700
 701        /* Check the max_count ... */
 702        switch (revs->max_count) {
 703        case -1:
 704                break;
 705        case 0:
 706                return NULL;
 707        default:
 708                revs->max_count--;
 709        }
 710
 711        do {
 712                struct commit *commit = revs->commits->item;
 713
 714                if (commit->object.flags & (UNINTERESTING|SHOWN))
 715                        goto next;
 716                if (revs->min_age != -1 && (commit->date > revs->min_age))
 717                        goto next;
 718                if (revs->max_age != -1 && (commit->date < revs->max_age))
 719                        return NULL;
 720                if (revs->no_merges && commit->parents && commit->parents->next)
 721                        goto next;
 722                if (revs->paths && revs->dense) {
 723                        if (!(commit->object.flags & TREECHANGE))
 724                                goto next;
 725                        rewrite_parents(commit);
 726                }
 727                /* More to go? */
 728                if (revs->max_count)
 729                        pop_most_recent_commit(&revs->commits, SEEN);
 730                commit->object.flags |= SHOWN;
 731                return commit;
 732next:
 733                pop_most_recent_commit(&revs->commits, SEEN);
 734        } while (revs->commits);
 735        return NULL;
 736}