revision.con commit Merge branch 'jc/withraw' into next (6b32ee2)
   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_type, &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
 317                                 * paths from this parent, so the
 318                                 * history beyond this parent is not
 319                                 * interesting.  Remove its parents
 320                                 * (they are grandparents for us).
 321                                 * IOW, we pretend this parent is a
 322                                 * "root" commit.
 323                                 */
 324                                parse_commit(p);
 325                                p->parents = NULL;
 326                        }
 327                /* fallthrough */
 328                case REV_TREE_DIFFERENT:
 329                        tree_changed = 1;
 330                        pp = &parent->next;
 331                        continue;
 332                }
 333                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 334        }
 335        if (tree_changed)
 336                commit->object.flags |= TREECHANGE;
 337}
 338
 339static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 340{
 341        struct commit_list *parent = commit->parents;
 342
 343        if (commit->object.flags & ADDED)
 344                return;
 345        commit->object.flags |= ADDED;
 346
 347        /*
 348         * If the commit is uninteresting, don't try to
 349         * prune parents - we want the maximal uninteresting
 350         * set.
 351         *
 352         * Normally we haven't parsed the parent
 353         * yet, so we won't have a parent of a parent
 354         * here. However, it may turn out that we've
 355         * reached this commit some other way (where it
 356         * wasn't uninteresting), in which case we need
 357         * to mark its parents recursively too..
 358         */
 359        if (commit->object.flags & UNINTERESTING) {
 360                while (parent) {
 361                        struct commit *p = parent->item;
 362                        parent = parent->next;
 363                        parse_commit(p);
 364                        p->object.flags |= UNINTERESTING;
 365                        if (p->parents)
 366                                mark_parents_uninteresting(p);
 367                        if (p->object.flags & SEEN)
 368                                continue;
 369                        p->object.flags |= SEEN;
 370                        insert_by_date(p, list);
 371                }
 372                return;
 373        }
 374
 375        /*
 376         * Ok, the commit wasn't uninteresting. Try to
 377         * simplify the commit history and find the parent
 378         * that has no differences in the path set if one exists.
 379         */
 380        if (revs->prune_fn)
 381                revs->prune_fn(revs, commit);
 382
 383        parent = commit->parents;
 384        while (parent) {
 385                struct commit *p = parent->item;
 386
 387                parent = parent->next;
 388
 389                parse_commit(p);
 390                if (p->object.flags & SEEN)
 391                        continue;
 392                p->object.flags |= SEEN;
 393                insert_by_date(p, list);
 394        }
 395}
 396
 397static void limit_list(struct rev_info *revs)
 398{
 399        struct commit_list *list = revs->commits;
 400        struct commit_list *newlist = NULL;
 401        struct commit_list **p = &newlist;
 402
 403        while (list) {
 404                struct commit_list *entry = list;
 405                struct commit *commit = list->item;
 406                struct object *obj = &commit->object;
 407
 408                list = list->next;
 409                free(entry);
 410
 411                if (revs->max_age != -1 && (commit->date < revs->max_age))
 412                        obj->flags |= UNINTERESTING;
 413                if (revs->unpacked && has_sha1_pack(obj->sha1))
 414                        obj->flags |= UNINTERESTING;
 415                add_parents_to_list(revs, commit, &list);
 416                if (obj->flags & UNINTERESTING) {
 417                        mark_parents_uninteresting(commit);
 418                        if (everybody_uninteresting(list))
 419                                break;
 420                        continue;
 421                }
 422                if (revs->min_age != -1 && (commit->date > revs->min_age))
 423                        continue;
 424                p = &commit_list_insert(commit, p)->next;
 425        }
 426        if (revs->boundary) {
 427                /* mark the ones that are on the result list first */
 428                for (list = newlist; list; list = list->next) {
 429                        struct commit *commit = list->item;
 430                        commit->object.flags |= TMP_MARK;
 431                }
 432                for (list = newlist; list; list = list->next) {
 433                        struct commit *commit = list->item;
 434                        struct object *obj = &commit->object;
 435                        struct commit_list *parent;
 436                        if (obj->flags & UNINTERESTING)
 437                                continue;
 438                        for (parent = commit->parents;
 439                             parent;
 440                             parent = parent->next) {
 441                                struct commit *pcommit = parent->item;
 442                                if (!(pcommit->object.flags & UNINTERESTING))
 443                                        continue;
 444                                pcommit->object.flags |= BOUNDARY;
 445                                if (pcommit->object.flags & TMP_MARK)
 446                                        continue;
 447                                pcommit->object.flags |= TMP_MARK;
 448                                p = &commit_list_insert(pcommit, p)->next;
 449                        }
 450                }
 451                for (list = newlist; list; list = list->next) {
 452                        struct commit *commit = list->item;
 453                        commit->object.flags &= ~TMP_MARK;
 454                }
 455        }
 456        revs->commits = newlist;
 457}
 458
 459static void add_one_commit(struct commit *commit, struct rev_info *revs)
 460{
 461        if (!commit || (commit->object.flags & SEEN))
 462                return;
 463        commit->object.flags |= SEEN;
 464        commit_list_insert(commit, &revs->commits);
 465}
 466
 467static int all_flags;
 468static struct rev_info *all_revs;
 469
 470static int handle_one_ref(const char *path, const unsigned char *sha1)
 471{
 472        struct commit *commit = get_commit_reference(all_revs, path, sha1, all_flags);
 473        add_one_commit(commit, all_revs);
 474        return 0;
 475}
 476
 477static void handle_all(struct rev_info *revs, unsigned flags)
 478{
 479        all_revs = revs;
 480        all_flags = flags;
 481        for_each_ref(handle_one_ref);
 482}
 483
 484void init_revisions(struct rev_info *revs)
 485{
 486        memset(revs, 0, sizeof(*revs));
 487        revs->lifo = 1;
 488        revs->dense = 1;
 489        revs->prefix = setup_git_directory();
 490        revs->max_age = -1;
 491        revs->min_age = -1;
 492        revs->max_count = -1;
 493
 494        revs->prune_fn = NULL;
 495        revs->prune_data = NULL;
 496
 497        revs->topo_setter = topo_sort_default_setter;
 498        revs->topo_getter = topo_sort_default_getter;
 499}
 500
 501/*
 502 * Parse revision information, filling in the "rev_info" structure,
 503 * and removing the used arguments from the argument list.
 504 *
 505 * Returns the number of arguments left that weren't recognized
 506 * (which are also moved to the head of the argument list)
 507 */
 508int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 509{
 510        int i, flags, seen_dashdash;
 511        const char **unrecognized = argv + 1;
 512        int left = 1;
 513
 514        init_revisions(revs);
 515
 516        /* First, search for "--" */
 517        seen_dashdash = 0;
 518        for (i = 1; i < argc; i++) {
 519                const char *arg = argv[i];
 520                if (strcmp(arg, "--"))
 521                        continue;
 522                argv[i] = NULL;
 523                argc = i;
 524                revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 525                seen_dashdash = 1;
 526                break;
 527        }
 528
 529        flags = 0;
 530        for (i = 1; i < argc; i++) {
 531                struct commit *commit;
 532                const char *arg = argv[i];
 533                unsigned char sha1[20];
 534                char *dotdot;
 535                int local_flags;
 536
 537                if (*arg == '-') {
 538                        if (!strncmp(arg, "--max-count=", 12)) {
 539                                revs->max_count = atoi(arg + 12);
 540                                continue;
 541                        }
 542                        /* accept -<digit>, like traditilnal "head" */
 543                        if ((*arg == '-') && isdigit(arg[1])) {
 544                                revs->max_count = atoi(arg + 1);
 545                                continue;
 546                        }
 547                        if (!strcmp(arg, "-n")) {
 548                                if (argc <= i + 1)
 549                                        die("-n requires an argument");
 550                                revs->max_count = atoi(argv[++i]);
 551                                continue;
 552                        }
 553                        if (!strncmp(arg,"-n",2)) {
 554                                revs->max_count = atoi(arg + 2);
 555                                continue;
 556                        }
 557                        if (!strncmp(arg, "--max-age=", 10)) {
 558                                revs->max_age = atoi(arg + 10);
 559                                continue;
 560                        }
 561                        if (!strncmp(arg, "--since=", 8)) {
 562                                revs->max_age = approxidate(arg + 8);
 563                                continue;
 564                        }
 565                        if (!strncmp(arg, "--after=", 8)) {
 566                                revs->max_age = approxidate(arg + 8);
 567                                continue;
 568                        }
 569                        if (!strncmp(arg, "--min-age=", 10)) {
 570                                revs->min_age = atoi(arg + 10);
 571                                continue;
 572                        }
 573                        if (!strncmp(arg, "--before=", 9)) {
 574                                revs->min_age = approxidate(arg + 9);
 575                                continue;
 576                        }
 577                        if (!strncmp(arg, "--until=", 8)) {
 578                                revs->min_age = approxidate(arg + 8);
 579                                continue;
 580                        }
 581                        if (!strcmp(arg, "--all")) {
 582                                handle_all(revs, flags);
 583                                continue;
 584                        }
 585                        if (!strcmp(arg, "--not")) {
 586                                flags ^= UNINTERESTING;
 587                                continue;
 588                        }
 589                        if (!strcmp(arg, "--default")) {
 590                                if (++i >= argc)
 591                                        die("bad --default argument");
 592                                def = argv[i];
 593                                continue;
 594                        }
 595                        if (!strcmp(arg, "--topo-order")) {
 596                                revs->topo_order = 1;
 597                                continue;
 598                        }
 599                        if (!strcmp(arg, "--date-order")) {
 600                                revs->lifo = 0;
 601                                revs->topo_order = 1;
 602                                continue;
 603                        }
 604                        if (!strcmp(arg, "--parents")) {
 605                                revs->parents = 1;
 606                                continue;
 607                        }
 608                        if (!strcmp(arg, "--dense")) {
 609                                revs->dense = 1;
 610                                continue;
 611                        }
 612                        if (!strcmp(arg, "--sparse")) {
 613                                revs->dense = 0;
 614                                continue;
 615                        }
 616                        if (!strcmp(arg, "--remove-empty")) {
 617                                revs->remove_empty_trees = 1;
 618                                continue;
 619                        }
 620                        if (!strcmp(arg, "--no-merges")) {
 621                                revs->no_merges = 1;
 622                                continue;
 623                        }
 624                        if (!strcmp(arg, "--boundary")) {
 625                                revs->boundary = 1;
 626                                continue;
 627                        }
 628                        if (!strcmp(arg, "--objects")) {
 629                                revs->tag_objects = 1;
 630                                revs->tree_objects = 1;
 631                                revs->blob_objects = 1;
 632                                continue;
 633                        }
 634                        if (!strcmp(arg, "--objects-edge")) {
 635                                revs->tag_objects = 1;
 636                                revs->tree_objects = 1;
 637                                revs->blob_objects = 1;
 638                                revs->edge_hint = 1;
 639                                continue;
 640                        }
 641                        if (!strcmp(arg, "--unpacked")) {
 642                                revs->unpacked = 1;
 643                                continue;
 644                        }
 645                        *unrecognized++ = arg;
 646                        left++;
 647                        continue;
 648                }
 649                dotdot = strstr(arg, "..");
 650                if (dotdot) {
 651                        unsigned char from_sha1[20];
 652                        const char *next = dotdot + 2;
 653                        const char *this = arg;
 654                        *dotdot = 0;
 655                        if (!*next)
 656                                next = "HEAD";
 657                        if (dotdot == arg)
 658                                this = "HEAD";
 659                        if (!get_sha1(this, from_sha1) &&
 660                            !get_sha1(next, sha1)) {
 661                                struct commit *exclude;
 662                                struct commit *include;
 663
 664                                exclude = get_commit_reference(revs, this, from_sha1, flags ^ UNINTERESTING);
 665                                include = get_commit_reference(revs, next, sha1, flags);
 666                                if (!exclude || !include)
 667                                        die("Invalid revision range %s..%s", arg, next);
 668                                add_one_commit(exclude, revs);
 669                                add_one_commit(include, revs);
 670                                continue;
 671                        }
 672                        *dotdot = '.';
 673                }
 674                local_flags = 0;
 675                if (*arg == '^') {
 676                        local_flags = UNINTERESTING;
 677                        arg++;
 678                }
 679                if (get_sha1(arg, sha1) < 0) {
 680                        struct stat st;
 681                        int j;
 682
 683                        if (seen_dashdash || local_flags)
 684                                die("bad revision '%s'", arg);
 685
 686                        /* If we didn't have a "--", all filenames must exist */
 687                        for (j = i; j < argc; j++) {
 688                                if (lstat(argv[j], &st) < 0)
 689                                        die("'%s': %s", argv[j], strerror(errno));
 690                        }
 691                        revs->prune_data = get_pathspec(revs->prefix, argv + i);
 692                        break;
 693                }
 694                commit = get_commit_reference(revs, arg, sha1, flags ^ local_flags);
 695                add_one_commit(commit, revs);
 696        }
 697        if (def && !revs->commits) {
 698                unsigned char sha1[20];
 699                struct commit *commit;
 700                if (get_sha1(def, sha1) < 0)
 701                        die("bad default revision '%s'", def);
 702                commit = get_commit_reference(revs, def, sha1, 0);
 703                add_one_commit(commit, revs);
 704        }
 705
 706        if (revs->topo_order || revs->unpacked)
 707                revs->limited = 1;
 708
 709        if (revs->prune_data) {
 710                diff_tree_setup_paths(revs->prune_data);
 711                revs->prune_fn = try_to_simplify_commit;
 712        }
 713
 714        return left;
 715}
 716
 717void prepare_revision_walk(struct rev_info *revs)
 718{
 719        sort_by_date(&revs->commits);
 720        if (revs->limited)
 721                limit_list(revs);
 722        if (revs->topo_order)
 723                sort_in_topological_order_fn(&revs->commits, revs->lifo,
 724                                             revs->topo_setter,
 725                                             revs->topo_getter);
 726}
 727
 728static int rewrite_one(struct rev_info *revs, struct commit **pp)
 729{
 730        for (;;) {
 731                struct commit *p = *pp;
 732                if (!revs->limited)
 733                        add_parents_to_list(revs, p, &revs->commits);
 734                if (p->object.flags & (TREECHANGE | UNINTERESTING))
 735                        return 0;
 736                if (!p->parents)
 737                        return -1;
 738                *pp = p->parents->item;
 739        }
 740}
 741
 742static void rewrite_parents(struct rev_info *revs, struct commit *commit)
 743{
 744        struct commit_list **pp = &commit->parents;
 745        while (*pp) {
 746                struct commit_list *parent = *pp;
 747                if (rewrite_one(revs, &parent->item) < 0) {
 748                        *pp = parent->next;
 749                        continue;
 750                }
 751                pp = &parent->next;
 752        }
 753}
 754
 755struct commit *get_revision(struct rev_info *revs)
 756{
 757        struct commit_list *list = revs->commits;
 758
 759        if (!list)
 760                return NULL;
 761
 762        /* Check the max_count ... */
 763        switch (revs->max_count) {
 764        case -1:
 765                break;
 766        case 0:
 767                return NULL;
 768        default:
 769                revs->max_count--;
 770        }
 771
 772        do {
 773                struct commit *commit = revs->commits->item;
 774
 775                revs->commits = revs->commits->next;
 776
 777                /*
 778                 * If we haven't done the list limiting, we need to look at
 779                 * the parents here. We also need to do the date-based limiting
 780                 * that we'd otherwise have done in limit_list().
 781                 */
 782                if (!revs->limited) {
 783                        if ((revs->unpacked &&
 784                             has_sha1_pack(commit->object.sha1)) ||
 785                            (revs->max_age != -1 &&
 786                             (commit->date < revs->max_age)))
 787                                continue;
 788                        add_parents_to_list(revs, commit, &revs->commits);
 789                }
 790                if (commit->object.flags & SHOWN)
 791                        continue;
 792                if (!(commit->object.flags & BOUNDARY) &&
 793                    (commit->object.flags & UNINTERESTING))
 794                        continue;
 795                if (revs->min_age != -1 && (commit->date > revs->min_age))
 796                        continue;
 797                if (revs->no_merges &&
 798                    commit->parents && commit->parents->next)
 799                        continue;
 800                if (revs->prune_fn && revs->dense) {
 801                        if (!(commit->object.flags & TREECHANGE))
 802                                continue;
 803                        if (revs->parents)
 804                                rewrite_parents(revs, commit);
 805                }
 806                commit->object.flags |= SHOWN;
 807                return commit;
 808        } while (revs->commits);
 809        return NULL;
 810}