revision.con commit Merge branch 'jc/empty' into next (3dcf2d0)
   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
 202static int tree_difference = REV_TREE_SAME;
 203
 204static void file_add_remove(struct diff_options *options,
 205                    int addremove, unsigned mode,
 206                    const unsigned char *sha1,
 207                    const char *base, const char *path)
 208{
 209        int diff = REV_TREE_DIFFERENT;
 210
 211        /*
 212         * Is it an add of a new file? It means that the old tree
 213         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 214         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 215         * (and if it already was "REV_TREE_NEW", we'll keep it
 216         * "REV_TREE_NEW" of course).
 217         */
 218        if (addremove == '+') {
 219                diff = tree_difference;
 220                if (diff != REV_TREE_SAME)
 221                        return;
 222                diff = REV_TREE_NEW;
 223        }
 224        tree_difference = diff;
 225}
 226
 227static void file_change(struct diff_options *options,
 228                 unsigned old_mode, unsigned new_mode,
 229                 const unsigned char *old_sha1,
 230                 const unsigned char *new_sha1,
 231                 const char *base, const char *path)
 232{
 233        tree_difference = REV_TREE_DIFFERENT;
 234}
 235
 236static struct diff_options diff_opt = {
 237        .recursive = 1,
 238        .add_remove = file_add_remove,
 239        .change = file_change,
 240};
 241
 242int rev_compare_tree(struct tree *t1, struct tree *t2)
 243{
 244        if (!t1)
 245                return REV_TREE_NEW;
 246        if (!t2)
 247                return REV_TREE_DIFFERENT;
 248        tree_difference = REV_TREE_SAME;
 249        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 250                return REV_TREE_DIFFERENT;
 251        return tree_difference;
 252}
 253
 254int rev_same_tree_as_empty(struct tree *t1)
 255{
 256        int retval;
 257        void *tree;
 258        struct tree_desc empty, real;
 259
 260        if (!t1)
 261                return 0;
 262
 263        tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 264        if (!tree)
 265                return 0;
 266        real.buf = tree;
 267
 268        empty.buf = "";
 269        empty.size = 0;
 270
 271        tree_difference = 0;
 272        retval = diff_tree(&empty, &real, "", &diff_opt);
 273        free(tree);
 274
 275        return retval >= 0 && !tree_difference;
 276}
 277
 278static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 279{
 280        struct commit_list **pp, *parent;
 281        int tree_changed = 0;
 282
 283        if (!commit->tree)
 284                return;
 285
 286        if (!commit->parents) {
 287                if (!rev_same_tree_as_empty(commit->tree))
 288                        commit->object.flags |= TREECHANGE;
 289                return;
 290        }
 291
 292        pp = &commit->parents;
 293        while ((parent = *pp) != NULL) {
 294                struct commit *p = parent->item;
 295
 296                parse_commit(p);
 297                switch (rev_compare_tree(p->tree, commit->tree)) {
 298                case REV_TREE_SAME:
 299                        if (p->object.flags & UNINTERESTING) {
 300                                /* Even if a merge with an uninteresting
 301                                 * side branch brought the entire change
 302                                 * we are interested in, we do not want
 303                                 * to lose the other branches of this
 304                                 * merge, so we just keep going.
 305                                 */
 306                                pp = &parent->next;
 307                                continue;
 308                        }
 309                        parent->next = NULL;
 310                        commit->parents = parent;
 311                        return;
 312
 313                case REV_TREE_NEW:
 314                        if (revs->remove_empty_trees &&
 315                            rev_same_tree_as_empty(p->tree)) {
 316                                /* We are adding all the specified paths from
 317                                 * this parent, so the parents of it is
 318                                 * not interesting, but the difference between
 319                                 * this parent and us still is interesting.
 320                                 */
 321                                p->object.flags |= UNINTERESTING;
 322                        }
 323                /* fallthrough */
 324                case REV_TREE_DIFFERENT:
 325                        tree_changed = 1;
 326                        pp = &parent->next;
 327                        continue;
 328                }
 329                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 330        }
 331        if (tree_changed)
 332                commit->object.flags |= TREECHANGE;
 333}
 334
 335static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 336{
 337        struct commit_list *parent = commit->parents;
 338
 339        /*
 340         * If the commit is uninteresting, don't try to
 341         * prune parents - we want the maximal uninteresting
 342         * set.
 343         *
 344         * Normally we haven't parsed the parent
 345         * yet, so we won't have a parent of a parent
 346         * here. However, it may turn out that we've
 347         * reached this commit some other way (where it
 348         * wasn't uninteresting), in which case we need
 349         * to mark its parents recursively too..
 350         */
 351        if (commit->object.flags & UNINTERESTING) {
 352                while (parent) {
 353                        struct commit *p = parent->item;
 354                        parent = parent->next;
 355                        parse_commit(p);
 356                        p->object.flags |= UNINTERESTING;
 357                        if (p->parents)
 358                                mark_parents_uninteresting(p);
 359                        if (p->object.flags & SEEN)
 360                                continue;
 361                        p->object.flags |= SEEN;
 362                        insert_by_date(p, list);
 363                }
 364                return;
 365        }
 366
 367        /*
 368         * Ok, the commit wasn't uninteresting. Try to
 369         * simplify the commit history and find the parent
 370         * that has no differences in the path set if one exists.
 371         */
 372        if (revs->prune_fn)
 373                revs->prune_fn(revs, commit);
 374
 375        parent = commit->parents;
 376        while (parent) {
 377                struct commit *p = parent->item;
 378
 379                parent = parent->next;
 380
 381                parse_commit(p);
 382                if (p->object.flags & SEEN)
 383                        continue;
 384                p->object.flags |= SEEN;
 385                insert_by_date(p, list);
 386        }
 387}
 388
 389static void limit_list(struct rev_info *revs)
 390{
 391        struct commit_list *list = revs->commits;
 392        struct commit_list *newlist = NULL;
 393        struct commit_list **p = &newlist;
 394
 395        while (list) {
 396                struct commit_list *entry = list;
 397                struct commit *commit = list->item;
 398                struct object *obj = &commit->object;
 399
 400                list = list->next;
 401                free(entry);
 402
 403                if (revs->max_age != -1 && (commit->date < revs->max_age))
 404                        obj->flags |= UNINTERESTING;
 405                if (revs->unpacked && has_sha1_pack(obj->sha1))
 406                        obj->flags |= UNINTERESTING;
 407                add_parents_to_list(revs, commit, &list);
 408                if (obj->flags & UNINTERESTING) {
 409                        mark_parents_uninteresting(commit);
 410                        if (everybody_uninteresting(list))
 411                                break;
 412                        continue;
 413                }
 414                if (revs->min_age != -1 && (commit->date > revs->min_age))
 415                        continue;
 416                p = &commit_list_insert(commit, p)->next;
 417        }
 418        revs->commits = newlist;
 419}
 420
 421static void add_one_commit(struct commit *commit, struct rev_info *revs)
 422{
 423        if (!commit || (commit->object.flags & SEEN))
 424                return;
 425        commit->object.flags |= SEEN;
 426        commit_list_insert(commit, &revs->commits);
 427}
 428
 429static int all_flags;
 430static struct rev_info *all_revs;
 431
 432static int handle_one_ref(const char *path, const unsigned char *sha1)
 433{
 434        struct commit *commit = get_commit_reference(all_revs, path, sha1, all_flags);
 435        add_one_commit(commit, all_revs);
 436        return 0;
 437}
 438
 439static void handle_all(struct rev_info *revs, unsigned flags)
 440{
 441        all_revs = revs;
 442        all_flags = flags;
 443        for_each_ref(handle_one_ref);
 444}
 445
 446void init_revisions(struct rev_info *revs)
 447{
 448        memset(revs, 0, sizeof(*revs));
 449        revs->lifo = 1;
 450        revs->dense = 1;
 451        revs->prefix = setup_git_directory();
 452        revs->max_age = -1;
 453        revs->min_age = -1;
 454        revs->max_count = -1;
 455
 456        revs->prune_fn = NULL;
 457        revs->prune_data = NULL;
 458
 459        revs->topo_setter = topo_sort_default_setter;
 460        revs->topo_getter = topo_sort_default_getter;
 461}
 462
 463/*
 464 * Parse revision information, filling in the "rev_info" structure,
 465 * and removing the used arguments from the argument list.
 466 *
 467 * Returns the number of arguments left that weren't recognized
 468 * (which are also moved to the head of the argument list)
 469 */
 470int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 471{
 472        int i, flags, seen_dashdash;
 473        const char **unrecognized = argv + 1;
 474        int left = 1;
 475
 476        init_revisions(revs);
 477
 478        /* First, search for "--" */
 479        seen_dashdash = 0;
 480        for (i = 1; i < argc; i++) {
 481                const char *arg = argv[i];
 482                if (strcmp(arg, "--"))
 483                        continue;
 484                argv[i] = NULL;
 485                argc = i;
 486                revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 487                seen_dashdash = 1;
 488                break;
 489        }
 490
 491        flags = 0;
 492        for (i = 1; i < argc; i++) {
 493                struct commit *commit;
 494                const char *arg = argv[i];
 495                unsigned char sha1[20];
 496                char *dotdot;
 497                int local_flags;
 498
 499                if (*arg == '-') {
 500                        if (!strncmp(arg, "--max-count=", 12)) {
 501                                revs->max_count = atoi(arg + 12);
 502                                continue;
 503                        }
 504                        /* accept -<digit>, like traditilnal "head" */
 505                        if ((*arg == '-') && isdigit(arg[1])) {
 506                                revs->max_count = atoi(arg + 1);
 507                                continue;
 508                        }
 509                        if (!strcmp(arg, "-n")) {
 510                                if (argc <= i + 1)
 511                                        die("-n requires an argument");
 512                                revs->max_count = atoi(argv[++i]);
 513                                continue;
 514                        }
 515                        if (!strncmp(arg,"-n",2)) {
 516                                revs->max_count = atoi(arg + 2);
 517                                continue;
 518                        }
 519                        if (!strncmp(arg, "--max-age=", 10)) {
 520                                revs->max_age = atoi(arg + 10);
 521                                revs->limited = 1;
 522                                continue;
 523                        }
 524                        if (!strncmp(arg, "--min-age=", 10)) {
 525                                revs->min_age = atoi(arg + 10);
 526                                revs->limited = 1;
 527                                continue;
 528                        }
 529                        if (!strncmp(arg, "--since=", 8)) {
 530                                revs->max_age = approxidate(arg + 8);
 531                                revs->limited = 1;
 532                                continue;
 533                        }
 534                        if (!strncmp(arg, "--after=", 8)) {
 535                                revs->max_age = approxidate(arg + 8);
 536                                revs->limited = 1;
 537                                continue;
 538                        }
 539                        if (!strncmp(arg, "--before=", 9)) {
 540                                revs->min_age = approxidate(arg + 9);
 541                                revs->limited = 1;
 542                                continue;
 543                        }
 544                        if (!strncmp(arg, "--until=", 8)) {
 545                                revs->min_age = approxidate(arg + 8);
 546                                revs->limited = 1;
 547                                continue;
 548                        }
 549                        if (!strcmp(arg, "--all")) {
 550                                handle_all(revs, flags);
 551                                continue;
 552                        }
 553                        if (!strcmp(arg, "--not")) {
 554                                flags ^= UNINTERESTING;
 555                                continue;
 556                        }
 557                        if (!strcmp(arg, "--default")) {
 558                                if (++i >= argc)
 559                                        die("bad --default argument");
 560                                def = argv[i];
 561                                continue;
 562                        }
 563                        if (!strcmp(arg, "--topo-order")) {
 564                                revs->topo_order = 1;
 565                                revs->limited = 1;
 566                                continue;
 567                        }
 568                        if (!strcmp(arg, "--date-order")) {
 569                                revs->lifo = 0;
 570                                revs->topo_order = 1;
 571                                revs->limited = 1;
 572                                continue;
 573                        }
 574                        if (!strcmp(arg, "--dense")) {
 575                                revs->dense = 1;
 576                                continue;
 577                        }
 578                        if (!strcmp(arg, "--sparse")) {
 579                                revs->dense = 0;
 580                                continue;
 581                        }
 582                        if (!strcmp(arg, "--remove-empty")) {
 583                                revs->remove_empty_trees = 1;
 584                                continue;
 585                        }
 586                        if (!strncmp(arg, "--no-merges", 11)) {
 587                                revs->no_merges = 1;
 588                                continue;
 589                        }
 590                        if (!strcmp(arg, "--objects")) {
 591                                revs->tag_objects = 1;
 592                                revs->tree_objects = 1;
 593                                revs->blob_objects = 1;
 594                                continue;
 595                        }
 596                        if (!strcmp(arg, "--objects-edge")) {
 597                                revs->tag_objects = 1;
 598                                revs->tree_objects = 1;
 599                                revs->blob_objects = 1;
 600                                revs->edge_hint = 1;
 601                                continue;
 602                        }
 603                        if (!strcmp(arg, "--unpacked")) {
 604                                revs->unpacked = 1;
 605                                revs->limited = 1;
 606                                continue;
 607                        }
 608                        *unrecognized++ = arg;
 609                        left++;
 610                        continue;
 611                }
 612                dotdot = strstr(arg, "..");
 613                if (dotdot) {
 614                        unsigned char from_sha1[20];
 615                        char *next = dotdot + 2;
 616                        *dotdot = 0;
 617                        if (!*next)
 618                                next = "HEAD";
 619                        if (!get_sha1(arg, from_sha1) && !get_sha1(next, sha1)) {
 620                                struct commit *exclude;
 621                                struct commit *include;
 622
 623                                exclude = get_commit_reference(revs, arg, from_sha1, flags ^ UNINTERESTING);
 624                                include = get_commit_reference(revs, next, sha1, flags);
 625                                if (!exclude || !include)
 626                                        die("Invalid revision range %s..%s", arg, next);
 627                                add_one_commit(exclude, revs);
 628                                add_one_commit(include, revs);
 629                                continue;
 630                        }
 631                        *dotdot = '.';
 632                }
 633                local_flags = 0;
 634                if (*arg == '^') {
 635                        local_flags = UNINTERESTING;
 636                        arg++;
 637                }
 638                if (get_sha1(arg, sha1) < 0) {
 639                        struct stat st;
 640                        int j;
 641
 642                        if (seen_dashdash || local_flags)
 643                                die("bad revision '%s'", arg);
 644
 645                        /* If we didn't have a "--", all filenames must exist */
 646                        for (j = i; j < argc; j++) {
 647                                if (lstat(argv[j], &st) < 0)
 648                                        die("'%s': %s", arg, strerror(errno));
 649                        }
 650                        revs->prune_data = get_pathspec(revs->prefix, argv + i);
 651                        break;
 652                }
 653                commit = get_commit_reference(revs, arg, sha1, flags ^ local_flags);
 654                add_one_commit(commit, revs);
 655        }
 656        if (def && !revs->commits) {
 657                unsigned char sha1[20];
 658                struct commit *commit;
 659                if (get_sha1(def, sha1) < 0)
 660                        die("bad default revision '%s'", def);
 661                commit = get_commit_reference(revs, def, sha1, 0);
 662                add_one_commit(commit, revs);
 663        }
 664
 665        if (revs->prune_data) {
 666                diff_tree_setup_paths(revs->prune_data);
 667                revs->prune_fn = try_to_simplify_commit;
 668                revs->limited = 1;
 669        }
 670
 671        return left;
 672}
 673
 674void prepare_revision_walk(struct rev_info *revs)
 675{
 676        sort_by_date(&revs->commits);
 677        if (revs->limited)
 678                limit_list(revs);
 679        if (revs->topo_order)
 680                sort_in_topological_order_fn(&revs->commits, revs->lifo,
 681                                             revs->topo_setter,
 682                                             revs->topo_getter);
 683}
 684
 685static int rewrite_one(struct commit **pp)
 686{
 687        for (;;) {
 688                struct commit *p = *pp;
 689                if (p->object.flags & (TREECHANGE | UNINTERESTING))
 690                        return 0;
 691                if (!p->parents)
 692                        return -1;
 693                *pp = p->parents->item;
 694        }
 695}
 696
 697static void rewrite_parents(struct commit *commit)
 698{
 699        struct commit_list **pp = &commit->parents;
 700        while (*pp) {
 701                struct commit_list *parent = *pp;
 702                if (rewrite_one(&parent->item) < 0) {
 703                        *pp = parent->next;
 704                        continue;
 705                }
 706                pp = &parent->next;
 707        }
 708}
 709
 710struct commit *get_revision(struct rev_info *revs)
 711{
 712        struct commit_list *list = revs->commits;
 713
 714        if (!list)
 715                return NULL;
 716
 717        /* Check the max_count ... */
 718        switch (revs->max_count) {
 719        case -1:
 720                break;
 721        case 0:
 722                return NULL;
 723        default:
 724                revs->max_count--;
 725        }
 726
 727        do {
 728                struct commit *commit = revs->commits->item;
 729
 730                if (commit->object.flags & (UNINTERESTING|SHOWN))
 731                        goto next;
 732                if (revs->min_age != -1 && (commit->date > revs->min_age))
 733                        goto next;
 734                if (revs->max_age != -1 && (commit->date < revs->max_age))
 735                        return NULL;
 736                if (revs->no_merges && commit->parents && commit->parents->next)
 737                        goto next;
 738                if (revs->prune_fn && revs->dense) {
 739                        if (!(commit->object.flags & TREECHANGE))
 740                                goto next;
 741                        rewrite_parents(commit);
 742                }
 743                /* More to go? */
 744                if (revs->max_count)
 745                        pop_most_recent_commit(&revs->commits, SEEN);
 746                commit->object.flags |= SHOWN;
 747                return commit;
 748next:
 749                pop_most_recent_commit(&revs->commits, SEEN);
 750        } while (revs->commits);
 751        return NULL;
 752}