revision.con commit Merge branch 'maint' (6169a89)
   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#include "grep.h"
  10#include "reflog-walk.h"
  11#include "patch-ids.h"
  12
  13static char *path_name(struct name_path *path, const char *name)
  14{
  15        struct name_path *p;
  16        char *n, *m;
  17        int nlen = strlen(name);
  18        int len = nlen + 1;
  19
  20        for (p = path; p; p = p->up) {
  21                if (p->elem_len)
  22                        len += p->elem_len + 1;
  23        }
  24        n = xmalloc(len);
  25        m = n + len - (nlen + 1);
  26        strcpy(m, name);
  27        for (p = path; p; p = p->up) {
  28                if (p->elem_len) {
  29                        m -= p->elem_len + 1;
  30                        memcpy(m, p->elem, p->elem_len);
  31                        m[p->elem_len] = '/';
  32                }
  33        }
  34        return n;
  35}
  36
  37void add_object(struct object *obj,
  38                struct object_array *p,
  39                struct name_path *path,
  40                const char *name)
  41{
  42        add_object_array(obj, path_name(path, name), p);
  43}
  44
  45static void mark_blob_uninteresting(struct blob *blob)
  46{
  47        if (blob->object.flags & UNINTERESTING)
  48                return;
  49        blob->object.flags |= UNINTERESTING;
  50}
  51
  52void mark_tree_uninteresting(struct tree *tree)
  53{
  54        struct tree_desc desc;
  55        struct name_entry entry;
  56        struct object *obj = &tree->object;
  57
  58        if (obj->flags & UNINTERESTING)
  59                return;
  60        obj->flags |= UNINTERESTING;
  61        if (!has_sha1_file(obj->sha1))
  62                return;
  63        if (parse_tree(tree) < 0)
  64                die("bad tree %s", sha1_to_hex(obj->sha1));
  65
  66        init_tree_desc(&desc, tree->buffer, tree->size);
  67        while (tree_entry(&desc, &entry)) {
  68                if (S_ISDIR(entry.mode))
  69                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  70                else
  71                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  72        }
  73
  74        /*
  75         * We don't care about the tree any more
  76         * after it has been marked uninteresting.
  77         */
  78        free(tree->buffer);
  79        tree->buffer = NULL;
  80}
  81
  82void mark_parents_uninteresting(struct commit *commit)
  83{
  84        struct commit_list *parents = commit->parents;
  85
  86        while (parents) {
  87                struct commit *commit = parents->item;
  88                if (!(commit->object.flags & UNINTERESTING)) {
  89                        commit->object.flags |= UNINTERESTING;
  90
  91                        /*
  92                         * Normally we haven't parsed the parent
  93                         * yet, so we won't have a parent of a parent
  94                         * here. However, it may turn out that we've
  95                         * reached this commit some other way (where it
  96                         * wasn't uninteresting), in which case we need
  97                         * to mark its parents recursively too..
  98                         */
  99                        if (commit->parents)
 100                                mark_parents_uninteresting(commit);
 101                }
 102
 103                /*
 104                 * A missing commit is ok iff its parent is marked
 105                 * uninteresting.
 106                 *
 107                 * We just mark such a thing parsed, so that when
 108                 * it is popped next time around, we won't be trying
 109                 * to parse it and get an error.
 110                 */
 111                if (!has_sha1_file(commit->object.sha1))
 112                        commit->object.parsed = 1;
 113                parents = parents->next;
 114        }
 115}
 116
 117void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 118{
 119        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 120}
 121
 122void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
 123{
 124        if (revs->no_walk && (obj->flags & UNINTERESTING))
 125                die("object ranges do not make sense when not walking revisions");
 126        add_object_array_with_mode(obj, name, &revs->pending, mode);
 127        if (revs->reflog_info && obj->type == OBJ_COMMIT)
 128                add_reflog_for_walk(revs->reflog_info,
 129                                (struct commit *)obj, name);
 130}
 131
 132static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 133{
 134        struct object *object;
 135
 136        object = parse_object(sha1);
 137        if (!object)
 138                die("bad object %s", name);
 139        object->flags |= flags;
 140        return object;
 141}
 142
 143static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 144{
 145        unsigned long flags = object->flags;
 146
 147        /*
 148         * Tag object? Look what it points to..
 149         */
 150        while (object->type == OBJ_TAG) {
 151                struct tag *tag = (struct tag *) object;
 152                if (revs->tag_objects && !(flags & UNINTERESTING))
 153                        add_pending_object(revs, object, tag->tag);
 154                object = parse_object(tag->tagged->sha1);
 155                if (!object)
 156                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 157        }
 158
 159        /*
 160         * Commit object? Just return it, we'll do all the complex
 161         * reachability crud.
 162         */
 163        if (object->type == OBJ_COMMIT) {
 164                struct commit *commit = (struct commit *)object;
 165                if (parse_commit(commit) < 0)
 166                        die("unable to parse commit %s", name);
 167                if (flags & UNINTERESTING) {
 168                        commit->object.flags |= UNINTERESTING;
 169                        mark_parents_uninteresting(commit);
 170                        revs->limited = 1;
 171                }
 172                return commit;
 173        }
 174
 175        /*
 176         * Tree object? Either mark it uniniteresting, or add it
 177         * to the list of objects to look at later..
 178         */
 179        if (object->type == OBJ_TREE) {
 180                struct tree *tree = (struct tree *)object;
 181                if (!revs->tree_objects)
 182                        return NULL;
 183                if (flags & UNINTERESTING) {
 184                        mark_tree_uninteresting(tree);
 185                        return NULL;
 186                }
 187                add_pending_object(revs, object, "");
 188                return NULL;
 189        }
 190
 191        /*
 192         * Blob object? You know the drill by now..
 193         */
 194        if (object->type == OBJ_BLOB) {
 195                struct blob *blob = (struct blob *)object;
 196                if (!revs->blob_objects)
 197                        return NULL;
 198                if (flags & UNINTERESTING) {
 199                        mark_blob_uninteresting(blob);
 200                        return NULL;
 201                }
 202                add_pending_object(revs, object, "");
 203                return NULL;
 204        }
 205        die("%s is unknown object", name);
 206}
 207
 208static int everybody_uninteresting(struct commit_list *orig)
 209{
 210        struct commit_list *list = orig;
 211        while (list) {
 212                struct commit *commit = list->item;
 213                list = list->next;
 214                if (commit->object.flags & UNINTERESTING)
 215                        continue;
 216                return 0;
 217        }
 218        return 1;
 219}
 220
 221/*
 222 * The goal is to get REV_TREE_NEW as the result only if the
 223 * diff consists of all '+' (and no other changes), and
 224 * REV_TREE_DIFFERENT otherwise (of course if the trees are
 225 * the same we want REV_TREE_SAME).  That means that once we
 226 * get to REV_TREE_DIFFERENT, we do not have to look any further.
 227 */
 228static int tree_difference = REV_TREE_SAME;
 229
 230static void file_add_remove(struct diff_options *options,
 231                    int addremove, unsigned mode,
 232                    const unsigned char *sha1,
 233                    const char *base, const char *path)
 234{
 235        int diff = REV_TREE_DIFFERENT;
 236
 237        /*
 238         * Is it an add of a new file? It means that the old tree
 239         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 240         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 241         * (and if it already was "REV_TREE_NEW", we'll keep it
 242         * "REV_TREE_NEW" of course).
 243         */
 244        if (addremove == '+') {
 245                diff = tree_difference;
 246                if (diff != REV_TREE_SAME)
 247                        return;
 248                diff = REV_TREE_NEW;
 249        }
 250        tree_difference = diff;
 251        if (tree_difference == REV_TREE_DIFFERENT)
 252                options->has_changes = 1;
 253}
 254
 255static void file_change(struct diff_options *options,
 256                 unsigned old_mode, unsigned new_mode,
 257                 const unsigned char *old_sha1,
 258                 const unsigned char *new_sha1,
 259                 const char *base, const char *path)
 260{
 261        tree_difference = REV_TREE_DIFFERENT;
 262        options->has_changes = 1;
 263}
 264
 265int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 266{
 267        if (!t1)
 268                return REV_TREE_NEW;
 269        if (!t2)
 270                return REV_TREE_DIFFERENT;
 271        tree_difference = REV_TREE_SAME;
 272        revs->pruning.has_changes = 0;
 273        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 274                           &revs->pruning) < 0)
 275                return REV_TREE_DIFFERENT;
 276        return tree_difference;
 277}
 278
 279int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 280{
 281        int retval;
 282        void *tree;
 283        unsigned long size;
 284        struct tree_desc empty, real;
 285
 286        if (!t1)
 287                return 0;
 288
 289        tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
 290        if (!tree)
 291                return 0;
 292        init_tree_desc(&real, tree, size);
 293        init_tree_desc(&empty, "", 0);
 294
 295        tree_difference = REV_TREE_SAME;
 296        revs->pruning.has_changes = 0;
 297        retval = diff_tree(&empty, &real, "", &revs->pruning);
 298        free(tree);
 299
 300        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 301}
 302
 303static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 304{
 305        struct commit_list **pp, *parent;
 306        int tree_changed = 0, tree_same = 0;
 307
 308        if (!commit->tree)
 309                return;
 310
 311        if (!commit->parents) {
 312                if (!rev_same_tree_as_empty(revs, commit->tree))
 313                        commit->object.flags |= TREECHANGE;
 314                return;
 315        }
 316
 317        pp = &commit->parents;
 318        while ((parent = *pp) != NULL) {
 319                struct commit *p = parent->item;
 320
 321                parse_commit(p);
 322                switch (rev_compare_tree(revs, p->tree, commit->tree)) {
 323                case REV_TREE_SAME:
 324                        tree_same = 1;
 325                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 326                                /* Even if a merge with an uninteresting
 327                                 * side branch brought the entire change
 328                                 * we are interested in, we do not want
 329                                 * to lose the other branches of this
 330                                 * merge, so we just keep going.
 331                                 */
 332                                pp = &parent->next;
 333                                continue;
 334                        }
 335                        parent->next = NULL;
 336                        commit->parents = parent;
 337                        return;
 338
 339                case REV_TREE_NEW:
 340                        if (revs->remove_empty_trees &&
 341                            rev_same_tree_as_empty(revs, p->tree)) {
 342                                /* We are adding all the specified
 343                                 * paths from this parent, so the
 344                                 * history beyond this parent is not
 345                                 * interesting.  Remove its parents
 346                                 * (they are grandparents for us).
 347                                 * IOW, we pretend this parent is a
 348                                 * "root" commit.
 349                                 */
 350                                parse_commit(p);
 351                                p->parents = NULL;
 352                        }
 353                /* fallthrough */
 354                case REV_TREE_DIFFERENT:
 355                        tree_changed = 1;
 356                        pp = &parent->next;
 357                        continue;
 358                }
 359                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 360        }
 361        if (tree_changed && !tree_same)
 362                commit->object.flags |= TREECHANGE;
 363}
 364
 365static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 366{
 367        struct commit_list *parent = commit->parents;
 368        unsigned left_flag;
 369        int add, rest;
 370
 371        if (commit->object.flags & ADDED)
 372                return;
 373        commit->object.flags |= ADDED;
 374
 375        /*
 376         * If the commit is uninteresting, don't try to
 377         * prune parents - we want the maximal uninteresting
 378         * set.
 379         *
 380         * Normally we haven't parsed the parent
 381         * yet, so we won't have a parent of a parent
 382         * here. However, it may turn out that we've
 383         * reached this commit some other way (where it
 384         * wasn't uninteresting), in which case we need
 385         * to mark its parents recursively too..
 386         */
 387        if (commit->object.flags & UNINTERESTING) {
 388                while (parent) {
 389                        struct commit *p = parent->item;
 390                        parent = parent->next;
 391                        parse_commit(p);
 392                        p->object.flags |= UNINTERESTING;
 393                        if (p->parents)
 394                                mark_parents_uninteresting(p);
 395                        if (p->object.flags & SEEN)
 396                                continue;
 397                        p->object.flags |= SEEN;
 398                        insert_by_date(p, list);
 399                }
 400                return;
 401        }
 402
 403        /*
 404         * Ok, the commit wasn't uninteresting. Try to
 405         * simplify the commit history and find the parent
 406         * that has no differences in the path set if one exists.
 407         */
 408        if (revs->prune_fn)
 409                revs->prune_fn(revs, commit);
 410
 411        if (revs->no_walk)
 412                return;
 413
 414        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 415
 416        rest = !revs->first_parent_only;
 417        for (parent = commit->parents, add = 1; parent; add = rest) {
 418                struct commit *p = parent->item;
 419
 420                parent = parent->next;
 421                parse_commit(p);
 422                p->object.flags |= left_flag;
 423                if (p->object.flags & SEEN)
 424                        continue;
 425                p->object.flags |= SEEN;
 426                if (add)
 427                        insert_by_date(p, list);
 428        }
 429}
 430
 431static void cherry_pick_list(struct commit_list *list)
 432{
 433        struct commit_list *p;
 434        int left_count = 0, right_count = 0;
 435        int left_first;
 436        struct patch_ids ids;
 437
 438        /* First count the commits on the left and on the right */
 439        for (p = list; p; p = p->next) {
 440                struct commit *commit = p->item;
 441                unsigned flags = commit->object.flags;
 442                if (flags & BOUNDARY)
 443                        ;
 444                else if (flags & SYMMETRIC_LEFT)
 445                        left_count++;
 446                else
 447                        right_count++;
 448        }
 449
 450        left_first = left_count < right_count;
 451        init_patch_ids(&ids);
 452
 453        /* Compute patch-ids for one side */
 454        for (p = list; p; p = p->next) {
 455                struct commit *commit = p->item;
 456                unsigned flags = commit->object.flags;
 457
 458                if (flags & BOUNDARY)
 459                        continue;
 460                /*
 461                 * If we have fewer left, left_first is set and we omit
 462                 * commits on the right branch in this loop.  If we have
 463                 * fewer right, we skip the left ones.
 464                 */
 465                if (left_first != !!(flags & SYMMETRIC_LEFT))
 466                        continue;
 467                commit->util = add_commit_patch_id(commit, &ids);
 468        }
 469
 470        /* Check the other side */
 471        for (p = list; p; p = p->next) {
 472                struct commit *commit = p->item;
 473                struct patch_id *id;
 474                unsigned flags = commit->object.flags;
 475
 476                if (flags & BOUNDARY)
 477                        continue;
 478                /*
 479                 * If we have fewer left, left_first is set and we omit
 480                 * commits on the left branch in this loop.
 481                 */
 482                if (left_first == !!(flags & SYMMETRIC_LEFT))
 483                        continue;
 484
 485                /*
 486                 * Have we seen the same patch id?
 487                 */
 488                id = has_commit_patch_id(commit, &ids);
 489                if (!id)
 490                        continue;
 491                id->seen = 1;
 492                commit->object.flags |= SHOWN;
 493        }
 494
 495        /* Now check the original side for seen ones */
 496        for (p = list; p; p = p->next) {
 497                struct commit *commit = p->item;
 498                struct patch_id *ent;
 499
 500                ent = commit->util;
 501                if (!ent)
 502                        continue;
 503                if (ent->seen)
 504                        commit->object.flags |= SHOWN;
 505                commit->util = NULL;
 506        }
 507
 508        free_patch_ids(&ids);
 509}
 510
 511static void limit_list(struct rev_info *revs)
 512{
 513        struct commit_list *list = revs->commits;
 514        struct commit_list *newlist = NULL;
 515        struct commit_list **p = &newlist;
 516
 517        while (list) {
 518                struct commit_list *entry = list;
 519                struct commit *commit = list->item;
 520                struct object *obj = &commit->object;
 521
 522                list = list->next;
 523                free(entry);
 524
 525                if (revs->max_age != -1 && (commit->date < revs->max_age))
 526                        obj->flags |= UNINTERESTING;
 527                add_parents_to_list(revs, commit, &list);
 528                if (obj->flags & UNINTERESTING) {
 529                        mark_parents_uninteresting(commit);
 530                        if (everybody_uninteresting(list))
 531                                break;
 532                        continue;
 533                }
 534                if (revs->min_age != -1 && (commit->date > revs->min_age))
 535                        continue;
 536                p = &commit_list_insert(commit, p)->next;
 537        }
 538        if (revs->cherry_pick)
 539                cherry_pick_list(newlist);
 540
 541        revs->commits = newlist;
 542}
 543
 544struct all_refs_cb {
 545        int all_flags;
 546        int warned_bad_reflog;
 547        struct rev_info *all_revs;
 548        const char *name_for_errormsg;
 549};
 550
 551static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 552{
 553        struct all_refs_cb *cb = cb_data;
 554        struct object *object = get_reference(cb->all_revs, path, sha1,
 555                                              cb->all_flags);
 556        add_pending_object(cb->all_revs, object, path);
 557        return 0;
 558}
 559
 560static void handle_all(struct rev_info *revs, unsigned flags)
 561{
 562        struct all_refs_cb cb;
 563        cb.all_revs = revs;
 564        cb.all_flags = flags;
 565        for_each_ref(handle_one_ref, &cb);
 566}
 567
 568static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 569{
 570        struct all_refs_cb *cb = cb_data;
 571        if (!is_null_sha1(sha1)) {
 572                struct object *o = parse_object(sha1);
 573                if (o) {
 574                        o->flags |= cb->all_flags;
 575                        add_pending_object(cb->all_revs, o, "");
 576                }
 577                else if (!cb->warned_bad_reflog) {
 578                        warning("reflog of '%s' references pruned commits",
 579                                cb->name_for_errormsg);
 580                        cb->warned_bad_reflog = 1;
 581                }
 582        }
 583}
 584
 585static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 586                const char *email, unsigned long timestamp, int tz,
 587                const char *message, void *cb_data)
 588{
 589        handle_one_reflog_commit(osha1, cb_data);
 590        handle_one_reflog_commit(nsha1, cb_data);
 591        return 0;
 592}
 593
 594static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 595{
 596        struct all_refs_cb *cb = cb_data;
 597        cb->warned_bad_reflog = 0;
 598        cb->name_for_errormsg = path;
 599        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
 600        return 0;
 601}
 602
 603static void handle_reflog(struct rev_info *revs, unsigned flags)
 604{
 605        struct all_refs_cb cb;
 606        cb.all_revs = revs;
 607        cb.all_flags = flags;
 608        for_each_reflog(handle_one_reflog, &cb);
 609}
 610
 611static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 612{
 613        unsigned char sha1[20];
 614        struct object *it;
 615        struct commit *commit;
 616        struct commit_list *parents;
 617
 618        if (*arg == '^') {
 619                flags ^= UNINTERESTING;
 620                arg++;
 621        }
 622        if (get_sha1(arg, sha1))
 623                return 0;
 624        while (1) {
 625                it = get_reference(revs, arg, sha1, 0);
 626                if (it->type != OBJ_TAG)
 627                        break;
 628                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 629        }
 630        if (it->type != OBJ_COMMIT)
 631                return 0;
 632        commit = (struct commit *)it;
 633        for (parents = commit->parents; parents; parents = parents->next) {
 634                it = &parents->item->object;
 635                it->flags |= flags;
 636                add_pending_object(revs, it, arg);
 637        }
 638        return 1;
 639}
 640
 641void init_revisions(struct rev_info *revs, const char *prefix)
 642{
 643        memset(revs, 0, sizeof(*revs));
 644
 645        revs->abbrev = DEFAULT_ABBREV;
 646        revs->ignore_merges = 1;
 647        revs->simplify_history = 1;
 648        revs->pruning.recursive = 1;
 649        revs->pruning.quiet = 1;
 650        revs->pruning.add_remove = file_add_remove;
 651        revs->pruning.change = file_change;
 652        revs->lifo = 1;
 653        revs->dense = 1;
 654        revs->prefix = prefix;
 655        revs->max_age = -1;
 656        revs->min_age = -1;
 657        revs->skip_count = -1;
 658        revs->max_count = -1;
 659        revs->subject_prefix = "PATCH";
 660
 661        revs->prune_fn = NULL;
 662        revs->prune_data = NULL;
 663
 664        revs->topo_setter = topo_sort_default_setter;
 665        revs->topo_getter = topo_sort_default_getter;
 666
 667        revs->commit_format = CMIT_FMT_DEFAULT;
 668
 669        diff_setup(&revs->diffopt);
 670}
 671
 672static void add_pending_commit_list(struct rev_info *revs,
 673                                    struct commit_list *commit_list,
 674                                    unsigned int flags)
 675{
 676        while (commit_list) {
 677                struct object *object = &commit_list->item->object;
 678                object->flags |= flags;
 679                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 680                commit_list = commit_list->next;
 681        }
 682}
 683
 684static void prepare_show_merge(struct rev_info *revs)
 685{
 686        struct commit_list *bases;
 687        struct commit *head, *other;
 688        unsigned char sha1[20];
 689        const char **prune = NULL;
 690        int i, prune_num = 1; /* counting terminating NULL */
 691
 692        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 693                die("--merge without HEAD?");
 694        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 695                die("--merge without MERGE_HEAD?");
 696        add_pending_object(revs, &head->object, "HEAD");
 697        add_pending_object(revs, &other->object, "MERGE_HEAD");
 698        bases = get_merge_bases(head, other, 1);
 699        while (bases) {
 700                struct commit *it = bases->item;
 701                struct commit_list *n = bases->next;
 702                free(bases);
 703                bases = n;
 704                it->object.flags |= UNINTERESTING;
 705                add_pending_object(revs, &it->object, "(merge-base)");
 706        }
 707
 708        if (!active_nr)
 709                read_cache();
 710        for (i = 0; i < active_nr; i++) {
 711                struct cache_entry *ce = active_cache[i];
 712                if (!ce_stage(ce))
 713                        continue;
 714                if (ce_path_match(ce, revs->prune_data)) {
 715                        prune_num++;
 716                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
 717                        prune[prune_num-2] = ce->name;
 718                        prune[prune_num-1] = NULL;
 719                }
 720                while ((i+1 < active_nr) &&
 721                       ce_same_name(ce, active_cache[i+1]))
 722                        i++;
 723        }
 724        revs->prune_data = prune;
 725}
 726
 727int handle_revision_arg(const char *arg, struct rev_info *revs,
 728                        int flags,
 729                        int cant_be_filename)
 730{
 731        unsigned mode;
 732        char *dotdot;
 733        struct object *object;
 734        unsigned char sha1[20];
 735        int local_flags;
 736
 737        dotdot = strstr(arg, "..");
 738        if (dotdot) {
 739                unsigned char from_sha1[20];
 740                const char *next = dotdot + 2;
 741                const char *this = arg;
 742                int symmetric = *next == '.';
 743                unsigned int flags_exclude = flags ^ UNINTERESTING;
 744
 745                *dotdot = 0;
 746                next += symmetric;
 747
 748                if (!*next)
 749                        next = "HEAD";
 750                if (dotdot == arg)
 751                        this = "HEAD";
 752                if (!get_sha1(this, from_sha1) &&
 753                    !get_sha1(next, sha1)) {
 754                        struct commit *a, *b;
 755                        struct commit_list *exclude;
 756
 757                        a = lookup_commit_reference(from_sha1);
 758                        b = lookup_commit_reference(sha1);
 759                        if (!a || !b) {
 760                                die(symmetric ?
 761                                    "Invalid symmetric difference expression %s...%s" :
 762                                    "Invalid revision range %s..%s",
 763                                    arg, next);
 764                        }
 765
 766                        if (!cant_be_filename) {
 767                                *dotdot = '.';
 768                                verify_non_filename(revs->prefix, arg);
 769                        }
 770
 771                        if (symmetric) {
 772                                exclude = get_merge_bases(a, b, 1);
 773                                add_pending_commit_list(revs, exclude,
 774                                                        flags_exclude);
 775                                free_commit_list(exclude);
 776                                a->object.flags |= flags | SYMMETRIC_LEFT;
 777                        } else
 778                                a->object.flags |= flags_exclude;
 779                        b->object.flags |= flags;
 780                        add_pending_object(revs, &a->object, this);
 781                        add_pending_object(revs, &b->object, next);
 782                        return 0;
 783                }
 784                *dotdot = '.';
 785        }
 786        dotdot = strstr(arg, "^@");
 787        if (dotdot && !dotdot[2]) {
 788                *dotdot = 0;
 789                if (add_parents_only(revs, arg, flags))
 790                        return 0;
 791                *dotdot = '^';
 792        }
 793        dotdot = strstr(arg, "^!");
 794        if (dotdot && !dotdot[2]) {
 795                *dotdot = 0;
 796                if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
 797                        *dotdot = '^';
 798        }
 799
 800        local_flags = 0;
 801        if (*arg == '^') {
 802                local_flags = UNINTERESTING;
 803                arg++;
 804        }
 805        if (get_sha1_with_mode(arg, sha1, &mode))
 806                return -1;
 807        if (!cant_be_filename)
 808                verify_non_filename(revs->prefix, arg);
 809        object = get_reference(revs, arg, sha1, flags ^ local_flags);
 810        add_pending_object_with_mode(revs, object, arg, mode);
 811        return 0;
 812}
 813
 814static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 815{
 816        if (!revs->grep_filter) {
 817                struct grep_opt *opt = xcalloc(1, sizeof(*opt));
 818                opt->status_only = 1;
 819                opt->pattern_tail = &(opt->pattern_list);
 820                opt->regflags = REG_NEWLINE;
 821                revs->grep_filter = opt;
 822        }
 823        append_grep_pattern(revs->grep_filter, ptn,
 824                            "command line", 0, what);
 825}
 826
 827static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
 828{
 829        char *pat;
 830        const char *prefix;
 831        int patlen, fldlen;
 832
 833        fldlen = strlen(field);
 834        patlen = strlen(pattern);
 835        pat = xmalloc(patlen + fldlen + 10);
 836        prefix = ".*";
 837        if (*pattern == '^') {
 838                prefix = "";
 839                pattern++;
 840        }
 841        sprintf(pat, "^%s %s%s", field, prefix, pattern);
 842        add_grep(revs, pat, GREP_PATTERN_HEAD);
 843}
 844
 845static void add_message_grep(struct rev_info *revs, const char *pattern)
 846{
 847        add_grep(revs, pattern, GREP_PATTERN_BODY);
 848}
 849
 850static void add_ignore_packed(struct rev_info *revs, const char *name)
 851{
 852        int num = ++revs->num_ignore_packed;
 853
 854        revs->ignore_packed = xrealloc(revs->ignore_packed,
 855                                       sizeof(const char **) * (num + 1));
 856        revs->ignore_packed[num-1] = name;
 857        revs->ignore_packed[num] = NULL;
 858}
 859
 860/*
 861 * Parse revision information, filling in the "rev_info" structure,
 862 * and removing the used arguments from the argument list.
 863 *
 864 * Returns the number of arguments left that weren't recognized
 865 * (which are also moved to the head of the argument list)
 866 */
 867int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 868{
 869        int i, flags, seen_dashdash, show_merge;
 870        const char **unrecognized = argv + 1;
 871        int left = 1;
 872        int all_match = 0;
 873
 874        /* First, search for "--" */
 875        seen_dashdash = 0;
 876        for (i = 1; i < argc; i++) {
 877                const char *arg = argv[i];
 878                if (strcmp(arg, "--"))
 879                        continue;
 880                argv[i] = NULL;
 881                argc = i;
 882                revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 883                seen_dashdash = 1;
 884                break;
 885        }
 886
 887        flags = show_merge = 0;
 888        for (i = 1; i < argc; i++) {
 889                const char *arg = argv[i];
 890                if (*arg == '-') {
 891                        int opts;
 892                        if (!prefixcmp(arg, "--max-count=")) {
 893                                revs->max_count = atoi(arg + 12);
 894                                continue;
 895                        }
 896                        if (!prefixcmp(arg, "--skip=")) {
 897                                revs->skip_count = atoi(arg + 7);
 898                                continue;
 899                        }
 900                        /* accept -<digit>, like traditional "head" */
 901                        if ((*arg == '-') && isdigit(arg[1])) {
 902                                revs->max_count = atoi(arg + 1);
 903                                continue;
 904                        }
 905                        if (!strcmp(arg, "-n")) {
 906                                if (argc <= i + 1)
 907                                        die("-n requires an argument");
 908                                revs->max_count = atoi(argv[++i]);
 909                                continue;
 910                        }
 911                        if (!prefixcmp(arg, "-n")) {
 912                                revs->max_count = atoi(arg + 2);
 913                                continue;
 914                        }
 915                        if (!prefixcmp(arg, "--max-age=")) {
 916                                revs->max_age = atoi(arg + 10);
 917                                continue;
 918                        }
 919                        if (!prefixcmp(arg, "--since=")) {
 920                                revs->max_age = approxidate(arg + 8);
 921                                continue;
 922                        }
 923                        if (!prefixcmp(arg, "--after=")) {
 924                                revs->max_age = approxidate(arg + 8);
 925                                continue;
 926                        }
 927                        if (!prefixcmp(arg, "--min-age=")) {
 928                                revs->min_age = atoi(arg + 10);
 929                                continue;
 930                        }
 931                        if (!prefixcmp(arg, "--before=")) {
 932                                revs->min_age = approxidate(arg + 9);
 933                                continue;
 934                        }
 935                        if (!prefixcmp(arg, "--until=")) {
 936                                revs->min_age = approxidate(arg + 8);
 937                                continue;
 938                        }
 939                        if (!strcmp(arg, "--all")) {
 940                                handle_all(revs, flags);
 941                                continue;
 942                        }
 943                        if (!strcmp(arg, "--first-parent")) {
 944                                revs->first_parent_only = 1;
 945                                continue;
 946                        }
 947                        if (!strcmp(arg, "--reflog")) {
 948                                handle_reflog(revs, flags);
 949                                continue;
 950                        }
 951                        if (!strcmp(arg, "-g") ||
 952                                        !strcmp(arg, "--walk-reflogs")) {
 953                                init_reflog_walk(&revs->reflog_info);
 954                                continue;
 955                        }
 956                        if (!strcmp(arg, "--not")) {
 957                                flags ^= UNINTERESTING;
 958                                continue;
 959                        }
 960                        if (!strcmp(arg, "--default")) {
 961                                if (++i >= argc)
 962                                        die("bad --default argument");
 963                                def = argv[i];
 964                                continue;
 965                        }
 966                        if (!strcmp(arg, "--merge")) {
 967                                show_merge = 1;
 968                                continue;
 969                        }
 970                        if (!strcmp(arg, "--topo-order")) {
 971                                revs->topo_order = 1;
 972                                continue;
 973                        }
 974                        if (!strcmp(arg, "--date-order")) {
 975                                revs->lifo = 0;
 976                                revs->topo_order = 1;
 977                                continue;
 978                        }
 979                        if (!strcmp(arg, "--parents")) {
 980                                revs->parents = 1;
 981                                continue;
 982                        }
 983                        if (!strcmp(arg, "--dense")) {
 984                                revs->dense = 1;
 985                                continue;
 986                        }
 987                        if (!strcmp(arg, "--sparse")) {
 988                                revs->dense = 0;
 989                                continue;
 990                        }
 991                        if (!strcmp(arg, "--remove-empty")) {
 992                                revs->remove_empty_trees = 1;
 993                                continue;
 994                        }
 995                        if (!strcmp(arg, "--no-merges")) {
 996                                revs->no_merges = 1;
 997                                continue;
 998                        }
 999                        if (!strcmp(arg, "--boundary")) {
1000                                revs->boundary = 1;
1001                                continue;
1002                        }
1003                        if (!strcmp(arg, "--left-right")) {
1004                                revs->left_right = 1;
1005                                continue;
1006                        }
1007                        if (!strcmp(arg, "--cherry-pick")) {
1008                                revs->cherry_pick = 1;
1009                                continue;
1010                        }
1011                        if (!strcmp(arg, "--objects")) {
1012                                revs->tag_objects = 1;
1013                                revs->tree_objects = 1;
1014                                revs->blob_objects = 1;
1015                                continue;
1016                        }
1017                        if (!strcmp(arg, "--objects-edge")) {
1018                                revs->tag_objects = 1;
1019                                revs->tree_objects = 1;
1020                                revs->blob_objects = 1;
1021                                revs->edge_hint = 1;
1022                                continue;
1023                        }
1024                        if (!strcmp(arg, "--unpacked")) {
1025                                revs->unpacked = 1;
1026                                free(revs->ignore_packed);
1027                                revs->ignore_packed = NULL;
1028                                revs->num_ignore_packed = 0;
1029                                continue;
1030                        }
1031                        if (!prefixcmp(arg, "--unpacked=")) {
1032                                revs->unpacked = 1;
1033                                add_ignore_packed(revs, arg+11);
1034                                continue;
1035                        }
1036                        if (!strcmp(arg, "-r")) {
1037                                revs->diff = 1;
1038                                revs->diffopt.recursive = 1;
1039                                continue;
1040                        }
1041                        if (!strcmp(arg, "-t")) {
1042                                revs->diff = 1;
1043                                revs->diffopt.recursive = 1;
1044                                revs->diffopt.tree_in_recursive = 1;
1045                                continue;
1046                        }
1047                        if (!strcmp(arg, "-m")) {
1048                                revs->ignore_merges = 0;
1049                                continue;
1050                        }
1051                        if (!strcmp(arg, "-c")) {
1052                                revs->diff = 1;
1053                                revs->dense_combined_merges = 0;
1054                                revs->combine_merges = 1;
1055                                continue;
1056                        }
1057                        if (!strcmp(arg, "--cc")) {
1058                                revs->diff = 1;
1059                                revs->dense_combined_merges = 1;
1060                                revs->combine_merges = 1;
1061                                continue;
1062                        }
1063                        if (!strcmp(arg, "-v")) {
1064                                revs->verbose_header = 1;
1065                                continue;
1066                        }
1067                        if (!prefixcmp(arg, "--pretty")) {
1068                                revs->verbose_header = 1;
1069                                revs->commit_format = get_commit_format(arg+8);
1070                                continue;
1071                        }
1072                        if (!strcmp(arg, "--root")) {
1073                                revs->show_root_diff = 1;
1074                                continue;
1075                        }
1076                        if (!strcmp(arg, "--no-commit-id")) {
1077                                revs->no_commit_id = 1;
1078                                continue;
1079                        }
1080                        if (!strcmp(arg, "--always")) {
1081                                revs->always_show_header = 1;
1082                                continue;
1083                        }
1084                        if (!strcmp(arg, "--no-abbrev")) {
1085                                revs->abbrev = 0;
1086                                continue;
1087                        }
1088                        if (!strcmp(arg, "--abbrev")) {
1089                                revs->abbrev = DEFAULT_ABBREV;
1090                                continue;
1091                        }
1092                        if (!prefixcmp(arg, "--abbrev=")) {
1093                                revs->abbrev = strtoul(arg + 9, NULL, 10);
1094                                if (revs->abbrev < MINIMUM_ABBREV)
1095                                        revs->abbrev = MINIMUM_ABBREV;
1096                                else if (revs->abbrev > 40)
1097                                        revs->abbrev = 40;
1098                                continue;
1099                        }
1100                        if (!strcmp(arg, "--abbrev-commit")) {
1101                                revs->abbrev_commit = 1;
1102                                continue;
1103                        }
1104                        if (!strcmp(arg, "--full-diff")) {
1105                                revs->diff = 1;
1106                                revs->full_diff = 1;
1107                                continue;
1108                        }
1109                        if (!strcmp(arg, "--full-history")) {
1110                                revs->simplify_history = 0;
1111                                continue;
1112                        }
1113                        if (!strcmp(arg, "--relative-date")) {
1114                                revs->date_mode = DATE_RELATIVE;
1115                                continue;
1116                        }
1117                        if (!strncmp(arg, "--date=", 7)) {
1118                                if (!strcmp(arg + 7, "relative"))
1119                                        revs->date_mode = DATE_RELATIVE;
1120                                else if (!strcmp(arg + 7, "local"))
1121                                        revs->date_mode = DATE_LOCAL;
1122                                else if (!strcmp(arg + 7, "default"))
1123                                        revs->date_mode = DATE_NORMAL;
1124                                else
1125                                        die("unknown date format %s", arg);
1126                                continue;
1127                        }
1128
1129                        /*
1130                         * Grepping the commit log
1131                         */
1132                        if (!prefixcmp(arg, "--author=")) {
1133                                add_header_grep(revs, "author", arg+9);
1134                                continue;
1135                        }
1136                        if (!prefixcmp(arg, "--committer=")) {
1137                                add_header_grep(revs, "committer", arg+12);
1138                                continue;
1139                        }
1140                        if (!prefixcmp(arg, "--grep=")) {
1141                                add_message_grep(revs, arg+7);
1142                                continue;
1143                        }
1144                        if (!strcmp(arg, "--all-match")) {
1145                                all_match = 1;
1146                                continue;
1147                        }
1148                        if (!prefixcmp(arg, "--encoding=")) {
1149                                arg += 11;
1150                                if (strcmp(arg, "none"))
1151                                        git_log_output_encoding = xstrdup(arg);
1152                                else
1153                                        git_log_output_encoding = "";
1154                                continue;
1155                        }
1156                        if (!strcmp(arg, "--reverse")) {
1157                                revs->reverse ^= 1;
1158                                continue;
1159                        }
1160
1161                        opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
1162                        if (opts > 0) {
1163                                revs->diff = 1;
1164                                i += opts - 1;
1165                                continue;
1166                        }
1167                        *unrecognized++ = arg;
1168                        left++;
1169                        continue;
1170                }
1171
1172                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1173                        int j;
1174                        if (seen_dashdash || *arg == '^')
1175                                die("bad revision '%s'", arg);
1176
1177                        /* If we didn't have a "--":
1178                         * (1) all filenames must exist;
1179                         * (2) all rev-args must not be interpretable
1180                         *     as a valid filename.
1181                         * but the latter we have checked in the main loop.
1182                         */
1183                        for (j = i; j < argc; j++)
1184                                verify_filename(revs->prefix, argv[j]);
1185
1186                        revs->prune_data = get_pathspec(revs->prefix,
1187                                                        argv + i);
1188                        break;
1189                }
1190        }
1191
1192        if (show_merge)
1193                prepare_show_merge(revs);
1194        if (def && !revs->pending.nr) {
1195                unsigned char sha1[20];
1196                struct object *object;
1197                unsigned mode;
1198                if (get_sha1_with_mode(def, sha1, &mode))
1199                        die("bad default revision '%s'", def);
1200                object = get_reference(revs, def, sha1, 0);
1201                add_pending_object_with_mode(revs, object, def, mode);
1202        }
1203
1204        if (revs->topo_order)
1205                revs->limited = 1;
1206
1207        if (revs->prune_data) {
1208                diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1209                revs->prune_fn = try_to_simplify_commit;
1210                if (!revs->full_diff)
1211                        diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1212        }
1213        if (revs->combine_merges) {
1214                revs->ignore_merges = 0;
1215                if (revs->dense_combined_merges && !revs->diffopt.output_format)
1216                        revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1217        }
1218        revs->diffopt.abbrev = revs->abbrev;
1219        if (diff_setup_done(&revs->diffopt) < 0)
1220                die("diff_setup_done failed");
1221
1222        if (revs->grep_filter) {
1223                revs->grep_filter->all_match = all_match;
1224                compile_grep_patterns(revs->grep_filter);
1225        }
1226
1227        return left;
1228}
1229
1230void prepare_revision_walk(struct rev_info *revs)
1231{
1232        int nr = revs->pending.nr;
1233        struct object_array_entry *e, *list;
1234
1235        e = list = revs->pending.objects;
1236        revs->pending.nr = 0;
1237        revs->pending.alloc = 0;
1238        revs->pending.objects = NULL;
1239        while (--nr >= 0) {
1240                struct commit *commit = handle_commit(revs, e->item, e->name);
1241                if (commit) {
1242                        if (!(commit->object.flags & SEEN)) {
1243                                commit->object.flags |= SEEN;
1244                                insert_by_date(commit, &revs->commits);
1245                        }
1246                }
1247                e++;
1248        }
1249        free(list);
1250
1251        if (revs->no_walk)
1252                return;
1253        if (revs->limited)
1254                limit_list(revs);
1255        if (revs->topo_order)
1256                sort_in_topological_order_fn(&revs->commits, revs->lifo,
1257                                             revs->topo_setter,
1258                                             revs->topo_getter);
1259}
1260
1261static int rewrite_one(struct rev_info *revs, struct commit **pp)
1262{
1263        for (;;) {
1264                struct commit *p = *pp;
1265                if (!revs->limited)
1266                        add_parents_to_list(revs, p, &revs->commits);
1267                if (p->parents && p->parents->next)
1268                        return 0;
1269                if (p->object.flags & (TREECHANGE | UNINTERESTING))
1270                        return 0;
1271                if (!p->parents)
1272                        return -1;
1273                *pp = p->parents->item;
1274        }
1275}
1276
1277static void rewrite_parents(struct rev_info *revs, struct commit *commit)
1278{
1279        struct commit_list **pp = &commit->parents;
1280        while (*pp) {
1281                struct commit_list *parent = *pp;
1282                if (rewrite_one(revs, &parent->item) < 0) {
1283                        *pp = parent->next;
1284                        continue;
1285                }
1286                pp = &parent->next;
1287        }
1288}
1289
1290static int commit_match(struct commit *commit, struct rev_info *opt)
1291{
1292        if (!opt->grep_filter)
1293                return 1;
1294        return grep_buffer(opt->grep_filter,
1295                           NULL, /* we say nothing, not even filename */
1296                           commit->buffer, strlen(commit->buffer));
1297}
1298
1299static struct commit *get_revision_1(struct rev_info *revs)
1300{
1301        if (!revs->commits)
1302                return NULL;
1303
1304        do {
1305                struct commit_list *entry = revs->commits;
1306                struct commit *commit = entry->item;
1307
1308                revs->commits = entry->next;
1309                free(entry);
1310
1311                if (revs->reflog_info)
1312                        fake_reflog_parent(revs->reflog_info, commit);
1313
1314                /*
1315                 * If we haven't done the list limiting, we need to look at
1316                 * the parents here. We also need to do the date-based limiting
1317                 * that we'd otherwise have done in limit_list().
1318                 */
1319                if (!revs->limited) {
1320                        if (revs->max_age != -1 &&
1321                            (commit->date < revs->max_age))
1322                                continue;
1323                        add_parents_to_list(revs, commit, &revs->commits);
1324                }
1325                if (commit->object.flags & SHOWN)
1326                        continue;
1327
1328                if (revs->unpacked && has_sha1_pack(commit->object.sha1,
1329                                                    revs->ignore_packed))
1330                    continue;
1331
1332                if (commit->object.flags & UNINTERESTING)
1333                        continue;
1334                if (revs->min_age != -1 && (commit->date > revs->min_age))
1335                        continue;
1336                if (revs->no_merges &&
1337                    commit->parents && commit->parents->next)
1338                        continue;
1339                if (!commit_match(commit, revs))
1340                        continue;
1341                if (revs->prune_fn && revs->dense) {
1342                        /* Commit without changes? */
1343                        if (!(commit->object.flags & TREECHANGE)) {
1344                                /* drop merges unless we want parenthood */
1345                                if (!revs->parents)
1346                                        continue;
1347                                /* non-merge - always ignore it */
1348                                if (!commit->parents || !commit->parents->next)
1349                                        continue;
1350                        }
1351                        if (revs->parents)
1352                                rewrite_parents(revs, commit);
1353                }
1354                return commit;
1355        } while (revs->commits);
1356        return NULL;
1357}
1358
1359static void gc_boundary(struct object_array *array)
1360{
1361        unsigned nr = array->nr;
1362        unsigned alloc = array->alloc;
1363        struct object_array_entry *objects = array->objects;
1364
1365        if (alloc <= nr) {
1366                unsigned i, j;
1367                for (i = j = 0; i < nr; i++) {
1368                        if (objects[i].item->flags & SHOWN)
1369                                continue;
1370                        if (i != j)
1371                                objects[j] = objects[i];
1372                        j++;
1373                }
1374                for (i = j; i < nr; i++)
1375                        objects[i].item = NULL;
1376                array->nr = j;
1377        }
1378}
1379
1380struct commit *get_revision(struct rev_info *revs)
1381{
1382        struct commit *c = NULL;
1383        struct commit_list *l;
1384
1385        if (revs->boundary == 2) {
1386                unsigned i;
1387                struct object_array *array = &revs->boundary_commits;
1388                struct object_array_entry *objects = array->objects;
1389                for (i = 0; i < array->nr; i++) {
1390                        c = (struct commit *)(objects[i].item);
1391                        if (!c)
1392                                continue;
1393                        if (!(c->object.flags & CHILD_SHOWN))
1394                                continue;
1395                        if (!(c->object.flags & SHOWN))
1396                                break;
1397                }
1398                if (array->nr <= i)
1399                        return NULL;
1400
1401                c->object.flags |= SHOWN | BOUNDARY;
1402                return c;
1403        }
1404
1405        if (revs->reverse) {
1406                int limit = -1;
1407
1408                if (0 <= revs->max_count) {
1409                        limit = revs->max_count;
1410                        if (0 < revs->skip_count)
1411                                limit += revs->skip_count;
1412                }
1413                l = NULL;
1414                while ((c = get_revision_1(revs))) {
1415                        commit_list_insert(c, &l);
1416                        if ((0 < limit) && !--limit)
1417                                break;
1418                }
1419                revs->commits = l;
1420                revs->reverse = 0;
1421                revs->max_count = -1;
1422                c = NULL;
1423        }
1424
1425        /*
1426         * Now pick up what they want to give us
1427         */
1428        c = get_revision_1(revs);
1429        if (c) {
1430                while (0 < revs->skip_count) {
1431                        revs->skip_count--;
1432                        c = get_revision_1(revs);
1433                        if (!c)
1434                                break;
1435                }
1436        }
1437
1438        /*
1439         * Check the max_count.
1440         */
1441        switch (revs->max_count) {
1442        case -1:
1443                break;
1444        case 0:
1445                c = NULL;
1446                break;
1447        default:
1448                revs->max_count--;
1449        }
1450
1451        if (c)
1452                c->object.flags |= SHOWN;
1453
1454        if (!revs->boundary) {
1455                return c;
1456        }
1457
1458        if (!c) {
1459                /*
1460                 * get_revision_1() runs out the commits, and
1461                 * we are done computing the boundaries.
1462                 * switch to boundary commits output mode.
1463                 */
1464                revs->boundary = 2;
1465                return get_revision(revs);
1466        }
1467
1468        /*
1469         * boundary commits are the commits that are parents of the
1470         * ones we got from get_revision_1() but they themselves are
1471         * not returned from get_revision_1().  Before returning
1472         * 'c', we need to mark its parents that they could be boundaries.
1473         */
1474
1475        for (l = c->parents; l; l = l->next) {
1476                struct object *p;
1477                p = &(l->item->object);
1478                if (p->flags & (CHILD_SHOWN | SHOWN))
1479                        continue;
1480                p->flags |= CHILD_SHOWN;
1481                gc_boundary(&revs->boundary_commits);
1482                add_object_array(p, NULL, &revs->boundary_commits);
1483        }
1484
1485        return c;
1486}