f8a801d5f6e2f2198ab1bee39f4aff31ae929196
   1#include "cache.h"
   2#include "object-store.h"
   3#include "tag.h"
   4#include "blob.h"
   5#include "tree.h"
   6#include "commit.h"
   7#include "diff.h"
   8#include "refs.h"
   9#include "revision.h"
  10#include "repository.h"
  11#include "graph.h"
  12#include "grep.h"
  13#include "reflog-walk.h"
  14#include "patch-ids.h"
  15#include "decorate.h"
  16#include "log-tree.h"
  17#include "string-list.h"
  18#include "line-log.h"
  19#include "mailmap.h"
  20#include "commit-slab.h"
  21#include "dir.h"
  22#include "cache-tree.h"
  23#include "bisect.h"
  24#include "packfile.h"
  25#include "worktree.h"
  26#include "argv-array.h"
  27
  28volatile show_early_output_fn_t show_early_output;
  29
  30static const char *term_bad;
  31static const char *term_good;
  32
  33implement_shared_commit_slab(revision_sources, char *);
  34
  35void show_object_with_name(FILE *out, struct object *obj, const char *name)
  36{
  37        const char *p;
  38
  39        fprintf(out, "%s ", oid_to_hex(&obj->oid));
  40        for (p = name; *p && *p != '\n'; p++)
  41                fputc(*p, out);
  42        fputc('\n', out);
  43}
  44
  45static void mark_blob_uninteresting(struct blob *blob)
  46{
  47        if (!blob)
  48                return;
  49        if (blob->object.flags & UNINTERESTING)
  50                return;
  51        blob->object.flags |= UNINTERESTING;
  52}
  53
  54static void mark_tree_contents_uninteresting(struct tree *tree)
  55{
  56        struct tree_desc desc;
  57        struct name_entry entry;
  58
  59        if (parse_tree_gently(tree, 1) < 0)
  60                return;
  61
  62        init_tree_desc(&desc, tree->buffer, tree->size);
  63        while (tree_entry(&desc, &entry)) {
  64                switch (object_type(entry.mode)) {
  65                case OBJ_TREE:
  66                        mark_tree_uninteresting(lookup_tree(the_repository, entry.oid));
  67                        break;
  68                case OBJ_BLOB:
  69                        mark_blob_uninteresting(lookup_blob(the_repository, entry.oid));
  70                        break;
  71                default:
  72                        /* Subproject commit - not in this repository */
  73                        break;
  74                }
  75        }
  76
  77        /*
  78         * We don't care about the tree any more
  79         * after it has been marked uninteresting.
  80         */
  81        free_tree_buffer(tree);
  82}
  83
  84void mark_tree_uninteresting(struct tree *tree)
  85{
  86        struct object *obj;
  87
  88        if (!tree)
  89                return;
  90
  91        obj = &tree->object;
  92        if (obj->flags & UNINTERESTING)
  93                return;
  94        obj->flags |= UNINTERESTING;
  95        mark_tree_contents_uninteresting(tree);
  96}
  97
  98struct commit_stack {
  99        struct commit **items;
 100        size_t nr, alloc;
 101};
 102#define COMMIT_STACK_INIT { NULL, 0, 0 }
 103
 104static void commit_stack_push(struct commit_stack *stack, struct commit *commit)
 105{
 106        ALLOC_GROW(stack->items, stack->nr + 1, stack->alloc);
 107        stack->items[stack->nr++] = commit;
 108}
 109
 110static struct commit *commit_stack_pop(struct commit_stack *stack)
 111{
 112        return stack->nr ? stack->items[--stack->nr] : NULL;
 113}
 114
 115static void commit_stack_clear(struct commit_stack *stack)
 116{
 117        FREE_AND_NULL(stack->items);
 118        stack->nr = stack->alloc = 0;
 119}
 120
 121static void mark_one_parent_uninteresting(struct commit *commit,
 122                                          struct commit_stack *pending)
 123{
 124        struct commit_list *l;
 125
 126        if (commit->object.flags & UNINTERESTING)
 127                return;
 128        commit->object.flags |= UNINTERESTING;
 129
 130        /*
 131         * Normally we haven't parsed the parent
 132         * yet, so we won't have a parent of a parent
 133         * here. However, it may turn out that we've
 134         * reached this commit some other way (where it
 135         * wasn't uninteresting), in which case we need
 136         * to mark its parents recursively too..
 137         */
 138        for (l = commit->parents; l; l = l->next)
 139                commit_stack_push(pending, l->item);
 140}
 141
 142void mark_parents_uninteresting(struct commit *commit)
 143{
 144        struct commit_stack pending = COMMIT_STACK_INIT;
 145        struct commit_list *l;
 146
 147        for (l = commit->parents; l; l = l->next)
 148                mark_one_parent_uninteresting(l->item, &pending);
 149
 150        while (pending.nr > 0)
 151                mark_one_parent_uninteresting(commit_stack_pop(&pending),
 152                                              &pending);
 153
 154        commit_stack_clear(&pending);
 155}
 156
 157static void add_pending_object_with_path(struct rev_info *revs,
 158                                         struct object *obj,
 159                                         const char *name, unsigned mode,
 160                                         const char *path)
 161{
 162        if (!obj)
 163                return;
 164        if (revs->no_walk && (obj->flags & UNINTERESTING))
 165                revs->no_walk = 0;
 166        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 167                struct strbuf buf = STRBUF_INIT;
 168                int len = interpret_branch_name(name, 0, &buf, 0);
 169
 170                if (0 < len && name[len] && buf.len)
 171                        strbuf_addstr(&buf, name + len);
 172                add_reflog_for_walk(revs->reflog_info,
 173                                    (struct commit *)obj,
 174                                    buf.buf[0] ? buf.buf: name);
 175                strbuf_release(&buf);
 176                return; /* do not add the commit itself */
 177        }
 178        obj->flags |= USER_GIVEN;
 179        add_object_array_with_path(obj, name, &revs->pending, mode, path);
 180}
 181
 182static void add_pending_object_with_mode(struct rev_info *revs,
 183                                         struct object *obj,
 184                                         const char *name, unsigned mode)
 185{
 186        add_pending_object_with_path(revs, obj, name, mode, NULL);
 187}
 188
 189void add_pending_object(struct rev_info *revs,
 190                        struct object *obj, const char *name)
 191{
 192        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 193}
 194
 195void add_head_to_pending(struct rev_info *revs)
 196{
 197        struct object_id oid;
 198        struct object *obj;
 199        if (get_oid("HEAD", &oid))
 200                return;
 201        obj = parse_object(the_repository, &oid);
 202        if (!obj)
 203                return;
 204        add_pending_object(revs, obj, "HEAD");
 205}
 206
 207static struct object *get_reference(struct rev_info *revs, const char *name,
 208                                    const struct object_id *oid,
 209                                    unsigned int flags)
 210{
 211        struct object *object;
 212
 213        object = parse_object(the_repository, oid);
 214        if (!object) {
 215                if (revs->ignore_missing)
 216                        return object;
 217                if (revs->exclude_promisor_objects && is_promisor_object(oid))
 218                        return NULL;
 219                die("bad object %s", name);
 220        }
 221        object->flags |= flags;
 222        return object;
 223}
 224
 225void add_pending_oid(struct rev_info *revs, const char *name,
 226                      const struct object_id *oid, unsigned int flags)
 227{
 228        struct object *object = get_reference(revs, name, oid, flags);
 229        add_pending_object(revs, object, name);
 230}
 231
 232static struct commit *handle_commit(struct rev_info *revs,
 233                                    struct object_array_entry *entry)
 234{
 235        struct object *object = entry->item;
 236        const char *name = entry->name;
 237        const char *path = entry->path;
 238        unsigned int mode = entry->mode;
 239        unsigned long flags = object->flags;
 240
 241        /*
 242         * Tag object? Look what it points to..
 243         */
 244        while (object->type == OBJ_TAG) {
 245                struct tag *tag = (struct tag *) object;
 246                if (revs->tag_objects && !(flags & UNINTERESTING))
 247                        add_pending_object(revs, object, tag->tag);
 248                if (!tag->tagged)
 249                        die("bad tag");
 250                object = parse_object(the_repository, &tag->tagged->oid);
 251                if (!object) {
 252                        if (revs->ignore_missing_links || (flags & UNINTERESTING))
 253                                return NULL;
 254                        if (revs->exclude_promisor_objects &&
 255                            is_promisor_object(&tag->tagged->oid))
 256                                return NULL;
 257                        die("bad object %s", oid_to_hex(&tag->tagged->oid));
 258                }
 259                object->flags |= flags;
 260                /*
 261                 * We'll handle the tagged object by looping or dropping
 262                 * through to the non-tag handlers below. Do not
 263                 * propagate path data from the tag's pending entry.
 264                 */
 265                path = NULL;
 266                mode = 0;
 267        }
 268
 269        /*
 270         * Commit object? Just return it, we'll do all the complex
 271         * reachability crud.
 272         */
 273        if (object->type == OBJ_COMMIT) {
 274                struct commit *commit = (struct commit *)object;
 275
 276                if (parse_commit(commit) < 0)
 277                        die("unable to parse commit %s", name);
 278                if (flags & UNINTERESTING) {
 279                        mark_parents_uninteresting(commit);
 280                        revs->limited = 1;
 281                }
 282                if (revs->sources) {
 283                        char **slot = revision_sources_at(revs->sources, commit);
 284
 285                        if (!*slot)
 286                                *slot = xstrdup(name);
 287                }
 288                return commit;
 289        }
 290
 291        /*
 292         * Tree object? Either mark it uninteresting, or add it
 293         * to the list of objects to look at later..
 294         */
 295        if (object->type == OBJ_TREE) {
 296                struct tree *tree = (struct tree *)object;
 297                if (!revs->tree_objects)
 298                        return NULL;
 299                if (flags & UNINTERESTING) {
 300                        mark_tree_contents_uninteresting(tree);
 301                        return NULL;
 302                }
 303                add_pending_object_with_path(revs, object, name, mode, path);
 304                return NULL;
 305        }
 306
 307        /*
 308         * Blob object? You know the drill by now..
 309         */
 310        if (object->type == OBJ_BLOB) {
 311                if (!revs->blob_objects)
 312                        return NULL;
 313                if (flags & UNINTERESTING)
 314                        return NULL;
 315                add_pending_object_with_path(revs, object, name, mode, path);
 316                return NULL;
 317        }
 318        die("%s is unknown object", name);
 319}
 320
 321static int everybody_uninteresting(struct commit_list *orig,
 322                                   struct commit **interesting_cache)
 323{
 324        struct commit_list *list = orig;
 325
 326        if (*interesting_cache) {
 327                struct commit *commit = *interesting_cache;
 328                if (!(commit->object.flags & UNINTERESTING))
 329                        return 0;
 330        }
 331
 332        while (list) {
 333                struct commit *commit = list->item;
 334                list = list->next;
 335                if (commit->object.flags & UNINTERESTING)
 336                        continue;
 337
 338                *interesting_cache = commit;
 339                return 0;
 340        }
 341        return 1;
 342}
 343
 344/*
 345 * A definition of "relevant" commit that we can use to simplify limited graphs
 346 * by eliminating side branches.
 347 *
 348 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 349 * in our list), or that is a specified BOTTOM commit. Then after computing
 350 * a limited list, during processing we can generally ignore boundary merges
 351 * coming from outside the graph, (ie from irrelevant parents), and treat
 352 * those merges as if they were single-parent. TREESAME is defined to consider
 353 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 354 * we don't care if we were !TREESAME to non-graph parents.
 355 *
 356 * Treating bottom commits as relevant ensures that a limited graph's
 357 * connection to the actual bottom commit is not viewed as a side branch, but
 358 * treated as part of the graph. For example:
 359 *
 360 *   ....Z...A---X---o---o---B
 361 *        .     /
 362 *         W---Y
 363 *
 364 * When computing "A..B", the A-X connection is at least as important as
 365 * Y-X, despite A being flagged UNINTERESTING.
 366 *
 367 * And when computing --ancestry-path "A..B", the A-X connection is more
 368 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 369 */
 370static inline int relevant_commit(struct commit *commit)
 371{
 372        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 373}
 374
 375/*
 376 * Return a single relevant commit from a parent list. If we are a TREESAME
 377 * commit, and this selects one of our parents, then we can safely simplify to
 378 * that parent.
 379 */
 380static struct commit *one_relevant_parent(const struct rev_info *revs,
 381                                          struct commit_list *orig)
 382{
 383        struct commit_list *list = orig;
 384        struct commit *relevant = NULL;
 385
 386        if (!orig)
 387                return NULL;
 388
 389        /*
 390         * For 1-parent commits, or if first-parent-only, then return that
 391         * first parent (even if not "relevant" by the above definition).
 392         * TREESAME will have been set purely on that parent.
 393         */
 394        if (revs->first_parent_only || !orig->next)
 395                return orig->item;
 396
 397        /*
 398         * For multi-parent commits, identify a sole relevant parent, if any.
 399         * If we have only one relevant parent, then TREESAME will be set purely
 400         * with regard to that parent, and we can simplify accordingly.
 401         *
 402         * If we have more than one relevant parent, or no relevant parents
 403         * (and multiple irrelevant ones), then we can't select a parent here
 404         * and return NULL.
 405         */
 406        while (list) {
 407                struct commit *commit = list->item;
 408                list = list->next;
 409                if (relevant_commit(commit)) {
 410                        if (relevant)
 411                                return NULL;
 412                        relevant = commit;
 413                }
 414        }
 415        return relevant;
 416}
 417
 418/*
 419 * The goal is to get REV_TREE_NEW as the result only if the
 420 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 421 * if the whole diff is removal of old data, and otherwise
 422 * REV_TREE_DIFFERENT (of course if the trees are the same we
 423 * want REV_TREE_SAME).
 424 *
 425 * The only time we care about the distinction is when
 426 * remove_empty_trees is in effect, in which case we care only about
 427 * whether the whole change is REV_TREE_NEW, or if there's another type
 428 * of change. Which means we can stop the diff early in either of these
 429 * cases:
 430 *
 431 *   1. We're not using remove_empty_trees at all.
 432 *
 433 *   2. We saw anything except REV_TREE_NEW.
 434 */
 435static int tree_difference = REV_TREE_SAME;
 436
 437static void file_add_remove(struct diff_options *options,
 438                    int addremove, unsigned mode,
 439                    const struct object_id *oid,
 440                    int oid_valid,
 441                    const char *fullpath, unsigned dirty_submodule)
 442{
 443        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 444        struct rev_info *revs = options->change_fn_data;
 445
 446        tree_difference |= diff;
 447        if (!revs->remove_empty_trees || tree_difference != REV_TREE_NEW)
 448                options->flags.has_changes = 1;
 449}
 450
 451static void file_change(struct diff_options *options,
 452                 unsigned old_mode, unsigned new_mode,
 453                 const struct object_id *old_oid,
 454                 const struct object_id *new_oid,
 455                 int old_oid_valid, int new_oid_valid,
 456                 const char *fullpath,
 457                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 458{
 459        tree_difference = REV_TREE_DIFFERENT;
 460        options->flags.has_changes = 1;
 461}
 462
 463static int rev_compare_tree(struct rev_info *revs,
 464                            struct commit *parent, struct commit *commit)
 465{
 466        struct tree *t1 = get_commit_tree(parent);
 467        struct tree *t2 = get_commit_tree(commit);
 468
 469        if (!t1)
 470                return REV_TREE_NEW;
 471        if (!t2)
 472                return REV_TREE_OLD;
 473
 474        if (revs->simplify_by_decoration) {
 475                /*
 476                 * If we are simplifying by decoration, then the commit
 477                 * is worth showing if it has a tag pointing at it.
 478                 */
 479                if (get_name_decoration(&commit->object))
 480                        return REV_TREE_DIFFERENT;
 481                /*
 482                 * A commit that is not pointed by a tag is uninteresting
 483                 * if we are not limited by path.  This means that you will
 484                 * see the usual "commits that touch the paths" plus any
 485                 * tagged commit by specifying both --simplify-by-decoration
 486                 * and pathspec.
 487                 */
 488                if (!revs->prune_data.nr)
 489                        return REV_TREE_SAME;
 490        }
 491
 492        tree_difference = REV_TREE_SAME;
 493        revs->pruning.flags.has_changes = 0;
 494        if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
 495                           &revs->pruning) < 0)
 496                return REV_TREE_DIFFERENT;
 497        return tree_difference;
 498}
 499
 500static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 501{
 502        int retval;
 503        struct tree *t1 = get_commit_tree(commit);
 504
 505        if (!t1)
 506                return 0;
 507
 508        tree_difference = REV_TREE_SAME;
 509        revs->pruning.flags.has_changes = 0;
 510        retval = diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);
 511
 512        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 513}
 514
 515struct treesame_state {
 516        unsigned int nparents;
 517        unsigned char treesame[FLEX_ARRAY];
 518};
 519
 520static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 521{
 522        unsigned n = commit_list_count(commit->parents);
 523        struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 524        st->nparents = n;
 525        add_decoration(&revs->treesame, &commit->object, st);
 526        return st;
 527}
 528
 529/*
 530 * Must be called immediately after removing the nth_parent from a commit's
 531 * parent list, if we are maintaining the per-parent treesame[] decoration.
 532 * This does not recalculate the master TREESAME flag - update_treesame()
 533 * should be called to update it after a sequence of treesame[] modifications
 534 * that may have affected it.
 535 */
 536static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 537{
 538        struct treesame_state *st;
 539        int old_same;
 540
 541        if (!commit->parents) {
 542                /*
 543                 * Have just removed the only parent from a non-merge.
 544                 * Different handling, as we lack decoration.
 545                 */
 546                if (nth_parent != 0)
 547                        die("compact_treesame %u", nth_parent);
 548                old_same = !!(commit->object.flags & TREESAME);
 549                if (rev_same_tree_as_empty(revs, commit))
 550                        commit->object.flags |= TREESAME;
 551                else
 552                        commit->object.flags &= ~TREESAME;
 553                return old_same;
 554        }
 555
 556        st = lookup_decoration(&revs->treesame, &commit->object);
 557        if (!st || nth_parent >= st->nparents)
 558                die("compact_treesame %u", nth_parent);
 559
 560        old_same = st->treesame[nth_parent];
 561        memmove(st->treesame + nth_parent,
 562                st->treesame + nth_parent + 1,
 563                st->nparents - nth_parent - 1);
 564
 565        /*
 566         * If we've just become a non-merge commit, update TREESAME
 567         * immediately, and remove the no-longer-needed decoration.
 568         * If still a merge, defer update until update_treesame().
 569         */
 570        if (--st->nparents == 1) {
 571                if (commit->parents->next)
 572                        die("compact_treesame parents mismatch");
 573                if (st->treesame[0] && revs->dense)
 574                        commit->object.flags |= TREESAME;
 575                else
 576                        commit->object.flags &= ~TREESAME;
 577                free(add_decoration(&revs->treesame, &commit->object, NULL));
 578        }
 579
 580        return old_same;
 581}
 582
 583static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 584{
 585        if (commit->parents && commit->parents->next) {
 586                unsigned n;
 587                struct treesame_state *st;
 588                struct commit_list *p;
 589                unsigned relevant_parents;
 590                unsigned relevant_change, irrelevant_change;
 591
 592                st = lookup_decoration(&revs->treesame, &commit->object);
 593                if (!st)
 594                        die("update_treesame %s", oid_to_hex(&commit->object.oid));
 595                relevant_parents = 0;
 596                relevant_change = irrelevant_change = 0;
 597                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 598                        if (relevant_commit(p->item)) {
 599                                relevant_change |= !st->treesame[n];
 600                                relevant_parents++;
 601                        } else
 602                                irrelevant_change |= !st->treesame[n];
 603                }
 604                if (relevant_parents ? relevant_change : irrelevant_change)
 605                        commit->object.flags &= ~TREESAME;
 606                else
 607                        commit->object.flags |= TREESAME;
 608        }
 609
 610        return commit->object.flags & TREESAME;
 611}
 612
 613static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 614{
 615        /*
 616         * TREESAME is irrelevant unless prune && dense;
 617         * if simplify_history is set, we can't have a mixture of TREESAME and
 618         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 619         *    decoration anyway);
 620         * if first_parent_only is set, then the TREESAME flag is locked
 621         *    against the first parent (and again we lack treesame[] decoration).
 622         */
 623        return revs->prune && revs->dense &&
 624               !revs->simplify_history &&
 625               !revs->first_parent_only;
 626}
 627
 628static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 629{
 630        struct commit_list **pp, *parent;
 631        struct treesame_state *ts = NULL;
 632        int relevant_change = 0, irrelevant_change = 0;
 633        int relevant_parents, nth_parent;
 634
 635        /*
 636         * If we don't do pruning, everything is interesting
 637         */
 638        if (!revs->prune)
 639                return;
 640
 641        if (!get_commit_tree(commit))
 642                return;
 643
 644        if (!commit->parents) {
 645                if (rev_same_tree_as_empty(revs, commit))
 646                        commit->object.flags |= TREESAME;
 647                return;
 648        }
 649
 650        /*
 651         * Normal non-merge commit? If we don't want to make the
 652         * history dense, we consider it always to be a change..
 653         */
 654        if (!revs->dense && !commit->parents->next)
 655                return;
 656
 657        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 658             (parent = *pp) != NULL;
 659             pp = &parent->next, nth_parent++) {
 660                struct commit *p = parent->item;
 661                if (relevant_commit(p))
 662                        relevant_parents++;
 663
 664                if (nth_parent == 1) {
 665                        /*
 666                         * This our second loop iteration - so we now know
 667                         * we're dealing with a merge.
 668                         *
 669                         * Do not compare with later parents when we care only about
 670                         * the first parent chain, in order to avoid derailing the
 671                         * traversal to follow a side branch that brought everything
 672                         * in the path we are limited to by the pathspec.
 673                         */
 674                        if (revs->first_parent_only)
 675                                break;
 676                        /*
 677                         * If this will remain a potentially-simplifiable
 678                         * merge, remember per-parent treesame if needed.
 679                         * Initialise the array with the comparison from our
 680                         * first iteration.
 681                         */
 682                        if (revs->treesame.name &&
 683                            !revs->simplify_history &&
 684                            !(commit->object.flags & UNINTERESTING)) {
 685                                ts = initialise_treesame(revs, commit);
 686                                if (!(irrelevant_change || relevant_change))
 687                                        ts->treesame[0] = 1;
 688                        }
 689                }
 690                if (parse_commit(p) < 0)
 691                        die("cannot simplify commit %s (because of %s)",
 692                            oid_to_hex(&commit->object.oid),
 693                            oid_to_hex(&p->object.oid));
 694                switch (rev_compare_tree(revs, p, commit)) {
 695                case REV_TREE_SAME:
 696                        if (!revs->simplify_history || !relevant_commit(p)) {
 697                                /* Even if a merge with an uninteresting
 698                                 * side branch brought the entire change
 699                                 * we are interested in, we do not want
 700                                 * to lose the other branches of this
 701                                 * merge, so we just keep going.
 702                                 */
 703                                if (ts)
 704                                        ts->treesame[nth_parent] = 1;
 705                                continue;
 706                        }
 707                        parent->next = NULL;
 708                        commit->parents = parent;
 709                        commit->object.flags |= TREESAME;
 710                        return;
 711
 712                case REV_TREE_NEW:
 713                        if (revs->remove_empty_trees &&
 714                            rev_same_tree_as_empty(revs, p)) {
 715                                /* We are adding all the specified
 716                                 * paths from this parent, so the
 717                                 * history beyond this parent is not
 718                                 * interesting.  Remove its parents
 719                                 * (they are grandparents for us).
 720                                 * IOW, we pretend this parent is a
 721                                 * "root" commit.
 722                                 */
 723                                if (parse_commit(p) < 0)
 724                                        die("cannot simplify commit %s (invalid %s)",
 725                                            oid_to_hex(&commit->object.oid),
 726                                            oid_to_hex(&p->object.oid));
 727                                p->parents = NULL;
 728                        }
 729                /* fallthrough */
 730                case REV_TREE_OLD:
 731                case REV_TREE_DIFFERENT:
 732                        if (relevant_commit(p))
 733                                relevant_change = 1;
 734                        else
 735                                irrelevant_change = 1;
 736                        continue;
 737                }
 738                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
 739        }
 740
 741        /*
 742         * TREESAME is straightforward for single-parent commits. For merge
 743         * commits, it is most useful to define it so that "irrelevant"
 744         * parents cannot make us !TREESAME - if we have any relevant
 745         * parents, then we only consider TREESAMEness with respect to them,
 746         * allowing irrelevant merges from uninteresting branches to be
 747         * simplified away. Only if we have only irrelevant parents do we
 748         * base TREESAME on them. Note that this logic is replicated in
 749         * update_treesame, which should be kept in sync.
 750         */
 751        if (relevant_parents ? !relevant_change : !irrelevant_change)
 752                commit->object.flags |= TREESAME;
 753}
 754
 755static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 756                    struct commit_list *cached_base, struct commit_list **cache)
 757{
 758        struct commit_list *new_entry;
 759
 760        if (cached_base && p->date < cached_base->item->date)
 761                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 762        else
 763                new_entry = commit_list_insert_by_date(p, head);
 764
 765        if (cache && (!*cache || p->date < (*cache)->item->date))
 766                *cache = new_entry;
 767}
 768
 769static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 770                    struct commit_list **list, struct commit_list **cache_ptr)
 771{
 772        struct commit_list *parent = commit->parents;
 773        unsigned left_flag;
 774        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 775
 776        if (commit->object.flags & ADDED)
 777                return 0;
 778        commit->object.flags |= ADDED;
 779
 780        if (revs->include_check &&
 781            !revs->include_check(commit, revs->include_check_data))
 782                return 0;
 783
 784        /*
 785         * If the commit is uninteresting, don't try to
 786         * prune parents - we want the maximal uninteresting
 787         * set.
 788         *
 789         * Normally we haven't parsed the parent
 790         * yet, so we won't have a parent of a parent
 791         * here. However, it may turn out that we've
 792         * reached this commit some other way (where it
 793         * wasn't uninteresting), in which case we need
 794         * to mark its parents recursively too..
 795         */
 796        if (commit->object.flags & UNINTERESTING) {
 797                while (parent) {
 798                        struct commit *p = parent->item;
 799                        parent = parent->next;
 800                        if (p)
 801                                p->object.flags |= UNINTERESTING;
 802                        if (parse_commit_gently(p, 1) < 0)
 803                                continue;
 804                        if (p->parents)
 805                                mark_parents_uninteresting(p);
 806                        if (p->object.flags & SEEN)
 807                                continue;
 808                        p->object.flags |= SEEN;
 809                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 810                }
 811                return 0;
 812        }
 813
 814        /*
 815         * Ok, the commit wasn't uninteresting. Try to
 816         * simplify the commit history and find the parent
 817         * that has no differences in the path set if one exists.
 818         */
 819        try_to_simplify_commit(revs, commit);
 820
 821        if (revs->no_walk)
 822                return 0;
 823
 824        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 825
 826        for (parent = commit->parents; parent; parent = parent->next) {
 827                struct commit *p = parent->item;
 828                int gently = revs->ignore_missing_links ||
 829                             revs->exclude_promisor_objects;
 830                if (parse_commit_gently(p, gently) < 0) {
 831                        if (revs->exclude_promisor_objects &&
 832                            is_promisor_object(&p->object.oid)) {
 833                                if (revs->first_parent_only)
 834                                        break;
 835                                continue;
 836                        }
 837                        return -1;
 838                }
 839                if (revs->sources) {
 840                        char **slot = revision_sources_at(revs->sources, p);
 841
 842                        if (!*slot)
 843                                *slot = *revision_sources_at(revs->sources, commit);
 844                }
 845                p->object.flags |= left_flag;
 846                if (!(p->object.flags & SEEN)) {
 847                        p->object.flags |= SEEN;
 848                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 849                }
 850                if (revs->first_parent_only)
 851                        break;
 852        }
 853        return 0;
 854}
 855
 856static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 857{
 858        struct commit_list *p;
 859        int left_count = 0, right_count = 0;
 860        int left_first;
 861        struct patch_ids ids;
 862        unsigned cherry_flag;
 863
 864        /* First count the commits on the left and on the right */
 865        for (p = list; p; p = p->next) {
 866                struct commit *commit = p->item;
 867                unsigned flags = commit->object.flags;
 868                if (flags & BOUNDARY)
 869                        ;
 870                else if (flags & SYMMETRIC_LEFT)
 871                        left_count++;
 872                else
 873                        right_count++;
 874        }
 875
 876        if (!left_count || !right_count)
 877                return;
 878
 879        left_first = left_count < right_count;
 880        init_patch_ids(revs->repo, &ids);
 881        ids.diffopts.pathspec = revs->diffopt.pathspec;
 882
 883        /* Compute patch-ids for one side */
 884        for (p = list; p; p = p->next) {
 885                struct commit *commit = p->item;
 886                unsigned flags = commit->object.flags;
 887
 888                if (flags & BOUNDARY)
 889                        continue;
 890                /*
 891                 * If we have fewer left, left_first is set and we omit
 892                 * commits on the right branch in this loop.  If we have
 893                 * fewer right, we skip the left ones.
 894                 */
 895                if (left_first != !!(flags & SYMMETRIC_LEFT))
 896                        continue;
 897                add_commit_patch_id(commit, &ids);
 898        }
 899
 900        /* either cherry_mark or cherry_pick are true */
 901        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 902
 903        /* Check the other side */
 904        for (p = list; p; p = p->next) {
 905                struct commit *commit = p->item;
 906                struct patch_id *id;
 907                unsigned flags = commit->object.flags;
 908
 909                if (flags & BOUNDARY)
 910                        continue;
 911                /*
 912                 * If we have fewer left, left_first is set and we omit
 913                 * commits on the left branch in this loop.
 914                 */
 915                if (left_first == !!(flags & SYMMETRIC_LEFT))
 916                        continue;
 917
 918                /*
 919                 * Have we seen the same patch id?
 920                 */
 921                id = has_commit_patch_id(commit, &ids);
 922                if (!id)
 923                        continue;
 924
 925                commit->object.flags |= cherry_flag;
 926                id->commit->object.flags |= cherry_flag;
 927        }
 928
 929        free_patch_ids(&ids);
 930}
 931
 932/* How many extra uninteresting commits we want to see.. */
 933#define SLOP 5
 934
 935static int still_interesting(struct commit_list *src, timestamp_t date, int slop,
 936                             struct commit **interesting_cache)
 937{
 938        /*
 939         * No source list at all? We're definitely done..
 940         */
 941        if (!src)
 942                return 0;
 943
 944        /*
 945         * Does the destination list contain entries with a date
 946         * before the source list? Definitely _not_ done.
 947         */
 948        if (date <= src->item->date)
 949                return SLOP;
 950
 951        /*
 952         * Does the source list still have interesting commits in
 953         * it? Definitely not done..
 954         */
 955        if (!everybody_uninteresting(src, interesting_cache))
 956                return SLOP;
 957
 958        /* Ok, we're closing in.. */
 959        return slop-1;
 960}
 961
 962/*
 963 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 964 * of B but not ancestors of A but further limits the result to those
 965 * that are descendants of A.  This takes the list of bottom commits and
 966 * the result of "A..B" without --ancestry-path, and limits the latter
 967 * further to the ones that can reach one of the commits in "bottom".
 968 */
 969static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 970{
 971        struct commit_list *p;
 972        struct commit_list *rlist = NULL;
 973        int made_progress;
 974
 975        /*
 976         * Reverse the list so that it will be likely that we would
 977         * process parents before children.
 978         */
 979        for (p = list; p; p = p->next)
 980                commit_list_insert(p->item, &rlist);
 981
 982        for (p = bottom; p; p = p->next)
 983                p->item->object.flags |= TMP_MARK;
 984
 985        /*
 986         * Mark the ones that can reach bottom commits in "list",
 987         * in a bottom-up fashion.
 988         */
 989        do {
 990                made_progress = 0;
 991                for (p = rlist; p; p = p->next) {
 992                        struct commit *c = p->item;
 993                        struct commit_list *parents;
 994                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 995                                continue;
 996                        for (parents = c->parents;
 997                             parents;
 998                             parents = parents->next) {
 999                                if (!(parents->item->object.flags & TMP_MARK))
1000                                        continue;
1001                                c->object.flags |= TMP_MARK;
1002                                made_progress = 1;
1003                                break;
1004                        }
1005                }
1006        } while (made_progress);
1007
1008        /*
1009         * NEEDSWORK: decide if we want to remove parents that are
1010         * not marked with TMP_MARK from commit->parents for commits
1011         * in the resulting list.  We may not want to do that, though.
1012         */
1013
1014        /*
1015         * The ones that are not marked with TMP_MARK are uninteresting
1016         */
1017        for (p = list; p; p = p->next) {
1018                struct commit *c = p->item;
1019                if (c->object.flags & TMP_MARK)
1020                        continue;
1021                c->object.flags |= UNINTERESTING;
1022        }
1023
1024        /* We are done with the TMP_MARK */
1025        for (p = list; p; p = p->next)
1026                p->item->object.flags &= ~TMP_MARK;
1027        for (p = bottom; p; p = p->next)
1028                p->item->object.flags &= ~TMP_MARK;
1029        free_commit_list(rlist);
1030}
1031
1032/*
1033 * Before walking the history, keep the set of "negative" refs the
1034 * caller has asked to exclude.
1035 *
1036 * This is used to compute "rev-list --ancestry-path A..B", as we need
1037 * to filter the result of "A..B" further to the ones that can actually
1038 * reach A.
1039 */
1040static struct commit_list *collect_bottom_commits(struct commit_list *list)
1041{
1042        struct commit_list *elem, *bottom = NULL;
1043        for (elem = list; elem; elem = elem->next)
1044                if (elem->item->object.flags & BOTTOM)
1045                        commit_list_insert(elem->item, &bottom);
1046        return bottom;
1047}
1048
1049/* Assumes either left_only or right_only is set */
1050static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1051{
1052        struct commit_list *p;
1053
1054        for (p = list; p; p = p->next) {
1055                struct commit *commit = p->item;
1056
1057                if (revs->right_only) {
1058                        if (commit->object.flags & SYMMETRIC_LEFT)
1059                                commit->object.flags |= SHOWN;
1060                } else  /* revs->left_only is set */
1061                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1062                                commit->object.flags |= SHOWN;
1063        }
1064}
1065
1066static int limit_list(struct rev_info *revs)
1067{
1068        int slop = SLOP;
1069        timestamp_t date = TIME_MAX;
1070        struct commit_list *list = revs->commits;
1071        struct commit_list *newlist = NULL;
1072        struct commit_list **p = &newlist;
1073        struct commit_list *bottom = NULL;
1074        struct commit *interesting_cache = NULL;
1075
1076        if (revs->ancestry_path) {
1077                bottom = collect_bottom_commits(list);
1078                if (!bottom)
1079                        die("--ancestry-path given but there are no bottom commits");
1080        }
1081
1082        while (list) {
1083                struct commit *commit = pop_commit(&list);
1084                struct object *obj = &commit->object;
1085                show_early_output_fn_t show;
1086
1087                if (commit == interesting_cache)
1088                        interesting_cache = NULL;
1089
1090                if (revs->max_age != -1 && (commit->date < revs->max_age))
1091                        obj->flags |= UNINTERESTING;
1092                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1093                        return -1;
1094                if (obj->flags & UNINTERESTING) {
1095                        mark_parents_uninteresting(commit);
1096                        slop = still_interesting(list, date, slop, &interesting_cache);
1097                        if (slop)
1098                                continue;
1099                        break;
1100                }
1101                if (revs->min_age != -1 && (commit->date > revs->min_age))
1102                        continue;
1103                date = commit->date;
1104                p = &commit_list_insert(commit, p)->next;
1105
1106                show = show_early_output;
1107                if (!show)
1108                        continue;
1109
1110                show(revs, newlist);
1111                show_early_output = NULL;
1112        }
1113        if (revs->cherry_pick || revs->cherry_mark)
1114                cherry_pick_list(newlist, revs);
1115
1116        if (revs->left_only || revs->right_only)
1117                limit_left_right(newlist, revs);
1118
1119        if (bottom) {
1120                limit_to_ancestry(bottom, newlist);
1121                free_commit_list(bottom);
1122        }
1123
1124        /*
1125         * Check if any commits have become TREESAME by some of their parents
1126         * becoming UNINTERESTING.
1127         */
1128        if (limiting_can_increase_treesame(revs))
1129                for (list = newlist; list; list = list->next) {
1130                        struct commit *c = list->item;
1131                        if (c->object.flags & (UNINTERESTING | TREESAME))
1132                                continue;
1133                        update_treesame(revs, c);
1134                }
1135
1136        revs->commits = newlist;
1137        return 0;
1138}
1139
1140/*
1141 * Add an entry to refs->cmdline with the specified information.
1142 * *name is copied.
1143 */
1144static void add_rev_cmdline(struct rev_info *revs,
1145                            struct object *item,
1146                            const char *name,
1147                            int whence,
1148                            unsigned flags)
1149{
1150        struct rev_cmdline_info *info = &revs->cmdline;
1151        unsigned int nr = info->nr;
1152
1153        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1154        info->rev[nr].item = item;
1155        info->rev[nr].name = xstrdup(name);
1156        info->rev[nr].whence = whence;
1157        info->rev[nr].flags = flags;
1158        info->nr++;
1159}
1160
1161static void add_rev_cmdline_list(struct rev_info *revs,
1162                                 struct commit_list *commit_list,
1163                                 int whence,
1164                                 unsigned flags)
1165{
1166        while (commit_list) {
1167                struct object *object = &commit_list->item->object;
1168                add_rev_cmdline(revs, object, oid_to_hex(&object->oid),
1169                                whence, flags);
1170                commit_list = commit_list->next;
1171        }
1172}
1173
1174struct all_refs_cb {
1175        int all_flags;
1176        int warned_bad_reflog;
1177        struct rev_info *all_revs;
1178        const char *name_for_errormsg;
1179        struct ref_store *refs;
1180};
1181
1182int ref_excluded(struct string_list *ref_excludes, const char *path)
1183{
1184        struct string_list_item *item;
1185
1186        if (!ref_excludes)
1187                return 0;
1188        for_each_string_list_item(item, ref_excludes) {
1189                if (!wildmatch(item->string, path, 0))
1190                        return 1;
1191        }
1192        return 0;
1193}
1194
1195static int handle_one_ref(const char *path, const struct object_id *oid,
1196                          int flag, void *cb_data)
1197{
1198        struct all_refs_cb *cb = cb_data;
1199        struct object *object;
1200
1201        if (ref_excluded(cb->all_revs->ref_excludes, path))
1202            return 0;
1203
1204        object = get_reference(cb->all_revs, path, oid, cb->all_flags);
1205        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1206        add_pending_oid(cb->all_revs, path, oid, cb->all_flags);
1207        return 0;
1208}
1209
1210static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1211        unsigned flags)
1212{
1213        cb->all_revs = revs;
1214        cb->all_flags = flags;
1215        revs->rev_input_given = 1;
1216        cb->refs = NULL;
1217}
1218
1219void clear_ref_exclusion(struct string_list **ref_excludes_p)
1220{
1221        if (*ref_excludes_p) {
1222                string_list_clear(*ref_excludes_p, 0);
1223                free(*ref_excludes_p);
1224        }
1225        *ref_excludes_p = NULL;
1226}
1227
1228void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1229{
1230        if (!*ref_excludes_p) {
1231                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1232                (*ref_excludes_p)->strdup_strings = 1;
1233        }
1234        string_list_append(*ref_excludes_p, exclude);
1235}
1236
1237static void handle_refs(struct ref_store *refs,
1238                        struct rev_info *revs, unsigned flags,
1239                        int (*for_each)(struct ref_store *, each_ref_fn, void *))
1240{
1241        struct all_refs_cb cb;
1242
1243        if (!refs) {
1244                /* this could happen with uninitialized submodules */
1245                return;
1246        }
1247
1248        init_all_refs_cb(&cb, revs, flags);
1249        for_each(refs, handle_one_ref, &cb);
1250}
1251
1252static void handle_one_reflog_commit(struct object_id *oid, void *cb_data)
1253{
1254        struct all_refs_cb *cb = cb_data;
1255        if (!is_null_oid(oid)) {
1256                struct object *o = parse_object(the_repository, oid);
1257                if (o) {
1258                        o->flags |= cb->all_flags;
1259                        /* ??? CMDLINEFLAGS ??? */
1260                        add_pending_object(cb->all_revs, o, "");
1261                }
1262                else if (!cb->warned_bad_reflog) {
1263                        warning("reflog of '%s' references pruned commits",
1264                                cb->name_for_errormsg);
1265                        cb->warned_bad_reflog = 1;
1266                }
1267        }
1268}
1269
1270static int handle_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
1271                const char *email, timestamp_t timestamp, int tz,
1272                const char *message, void *cb_data)
1273{
1274        handle_one_reflog_commit(ooid, cb_data);
1275        handle_one_reflog_commit(noid, cb_data);
1276        return 0;
1277}
1278
1279static int handle_one_reflog(const char *path, const struct object_id *oid,
1280                             int flag, void *cb_data)
1281{
1282        struct all_refs_cb *cb = cb_data;
1283        cb->warned_bad_reflog = 0;
1284        cb->name_for_errormsg = path;
1285        refs_for_each_reflog_ent(cb->refs, path,
1286                                 handle_one_reflog_ent, cb_data);
1287        return 0;
1288}
1289
1290static void add_other_reflogs_to_pending(struct all_refs_cb *cb)
1291{
1292        struct worktree **worktrees, **p;
1293
1294        worktrees = get_worktrees(0);
1295        for (p = worktrees; *p; p++) {
1296                struct worktree *wt = *p;
1297
1298                if (wt->is_current)
1299                        continue;
1300
1301                cb->refs = get_worktree_ref_store(wt);
1302                refs_for_each_reflog(cb->refs,
1303                                     handle_one_reflog,
1304                                     cb);
1305        }
1306        free_worktrees(worktrees);
1307}
1308
1309void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1310{
1311        struct all_refs_cb cb;
1312
1313        cb.all_revs = revs;
1314        cb.all_flags = flags;
1315        cb.refs = get_main_ref_store(the_repository);
1316        for_each_reflog(handle_one_reflog, &cb);
1317
1318        if (!revs->single_worktree)
1319                add_other_reflogs_to_pending(&cb);
1320}
1321
1322static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1323                           struct strbuf *path)
1324{
1325        size_t baselen = path->len;
1326        int i;
1327
1328        if (it->entry_count >= 0) {
1329                struct tree *tree = lookup_tree(the_repository, &it->oid);
1330                add_pending_object_with_path(revs, &tree->object, "",
1331                                             040000, path->buf);
1332        }
1333
1334        for (i = 0; i < it->subtree_nr; i++) {
1335                struct cache_tree_sub *sub = it->down[i];
1336                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1337                add_cache_tree(sub->cache_tree, revs, path);
1338                strbuf_setlen(path, baselen);
1339        }
1340
1341}
1342
1343static void do_add_index_objects_to_pending(struct rev_info *revs,
1344                                            struct index_state *istate)
1345{
1346        int i;
1347
1348        for (i = 0; i < istate->cache_nr; i++) {
1349                struct cache_entry *ce = istate->cache[i];
1350                struct blob *blob;
1351
1352                if (S_ISGITLINK(ce->ce_mode))
1353                        continue;
1354
1355                blob = lookup_blob(the_repository, &ce->oid);
1356                if (!blob)
1357                        die("unable to add index blob to traversal");
1358                add_pending_object_with_path(revs, &blob->object, "",
1359                                             ce->ce_mode, ce->name);
1360        }
1361
1362        if (istate->cache_tree) {
1363                struct strbuf path = STRBUF_INIT;
1364                add_cache_tree(istate->cache_tree, revs, &path);
1365                strbuf_release(&path);
1366        }
1367}
1368
1369void add_index_objects_to_pending(struct rev_info *revs, unsigned int flags)
1370{
1371        struct worktree **worktrees, **p;
1372
1373        read_index(revs->repo->index);
1374        do_add_index_objects_to_pending(revs, revs->repo->index);
1375
1376        if (revs->single_worktree)
1377                return;
1378
1379        worktrees = get_worktrees(0);
1380        for (p = worktrees; *p; p++) {
1381                struct worktree *wt = *p;
1382                struct index_state istate = { NULL };
1383
1384                if (wt->is_current)
1385                        continue; /* current index already taken care of */
1386
1387                if (read_index_from(&istate,
1388                                    worktree_git_path(wt, "index"),
1389                                    get_worktree_git_dir(wt)) > 0)
1390                        do_add_index_objects_to_pending(revs, &istate);
1391                discard_index(&istate);
1392        }
1393        free_worktrees(worktrees);
1394}
1395
1396static int add_parents_only(struct rev_info *revs, const char *arg_, int flags,
1397                            int exclude_parent)
1398{
1399        struct object_id oid;
1400        struct object *it;
1401        struct commit *commit;
1402        struct commit_list *parents;
1403        int parent_number;
1404        const char *arg = arg_;
1405
1406        if (*arg == '^') {
1407                flags ^= UNINTERESTING | BOTTOM;
1408                arg++;
1409        }
1410        if (get_oid_committish(arg, &oid))
1411                return 0;
1412        while (1) {
1413                it = get_reference(revs, arg, &oid, 0);
1414                if (!it && revs->ignore_missing)
1415                        return 0;
1416                if (it->type != OBJ_TAG)
1417                        break;
1418                if (!((struct tag*)it)->tagged)
1419                        return 0;
1420                oidcpy(&oid, &((struct tag*)it)->tagged->oid);
1421        }
1422        if (it->type != OBJ_COMMIT)
1423                return 0;
1424        commit = (struct commit *)it;
1425        if (exclude_parent &&
1426            exclude_parent > commit_list_count(commit->parents))
1427                return 0;
1428        for (parents = commit->parents, parent_number = 1;
1429             parents;
1430             parents = parents->next, parent_number++) {
1431                if (exclude_parent && parent_number != exclude_parent)
1432                        continue;
1433
1434                it = &parents->item->object;
1435                it->flags |= flags;
1436                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1437                add_pending_object(revs, it, arg);
1438        }
1439        return 1;
1440}
1441
1442void repo_init_revisions(struct repository *r,
1443                         struct rev_info *revs,
1444                         const char *prefix)
1445{
1446        memset(revs, 0, sizeof(*revs));
1447
1448        revs->repo = r;
1449        revs->abbrev = DEFAULT_ABBREV;
1450        revs->ignore_merges = 1;
1451        revs->simplify_history = 1;
1452        revs->pruning.flags.recursive = 1;
1453        revs->pruning.flags.quick = 1;
1454        revs->pruning.add_remove = file_add_remove;
1455        revs->pruning.change = file_change;
1456        revs->pruning.change_fn_data = revs;
1457        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1458        revs->dense = 1;
1459        revs->prefix = prefix;
1460        revs->max_age = -1;
1461        revs->min_age = -1;
1462        revs->skip_count = -1;
1463        revs->max_count = -1;
1464        revs->max_parents = -1;
1465        revs->expand_tabs_in_log = -1;
1466
1467        revs->commit_format = CMIT_FMT_DEFAULT;
1468        revs->expand_tabs_in_log_default = 8;
1469
1470        init_grep_defaults(revs->repo);
1471        grep_init(&revs->grep_filter, revs->repo, prefix);
1472        revs->grep_filter.status_only = 1;
1473
1474        repo_diff_setup(revs->repo, &revs->diffopt);
1475        if (prefix && !revs->diffopt.prefix) {
1476                revs->diffopt.prefix = prefix;
1477                revs->diffopt.prefix_length = strlen(prefix);
1478        }
1479
1480        revs->notes_opt.use_default_notes = -1;
1481}
1482
1483static void add_pending_commit_list(struct rev_info *revs,
1484                                    struct commit_list *commit_list,
1485                                    unsigned int flags)
1486{
1487        while (commit_list) {
1488                struct object *object = &commit_list->item->object;
1489                object->flags |= flags;
1490                add_pending_object(revs, object, oid_to_hex(&object->oid));
1491                commit_list = commit_list->next;
1492        }
1493}
1494
1495static void prepare_show_merge(struct rev_info *revs)
1496{
1497        struct commit_list *bases;
1498        struct commit *head, *other;
1499        struct object_id oid;
1500        const char **prune = NULL;
1501        int i, prune_num = 1; /* counting terminating NULL */
1502        struct index_state *istate = revs->repo->index;
1503
1504        if (get_oid("HEAD", &oid))
1505                die("--merge without HEAD?");
1506        head = lookup_commit_or_die(&oid, "HEAD");
1507        if (get_oid("MERGE_HEAD", &oid))
1508                die("--merge without MERGE_HEAD?");
1509        other = lookup_commit_or_die(&oid, "MERGE_HEAD");
1510        add_pending_object(revs, &head->object, "HEAD");
1511        add_pending_object(revs, &other->object, "MERGE_HEAD");
1512        bases = get_merge_bases(head, other);
1513        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1514        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1515        free_commit_list(bases);
1516        head->object.flags |= SYMMETRIC_LEFT;
1517
1518        if (!istate->cache_nr)
1519                read_index(istate);
1520        for (i = 0; i < istate->cache_nr; i++) {
1521                const struct cache_entry *ce = istate->cache[i];
1522                if (!ce_stage(ce))
1523                        continue;
1524                if (ce_path_match(istate, ce, &revs->prune_data, NULL)) {
1525                        prune_num++;
1526                        REALLOC_ARRAY(prune, prune_num);
1527                        prune[prune_num-2] = ce->name;
1528                        prune[prune_num-1] = NULL;
1529                }
1530                while ((i+1 < istate->cache_nr) &&
1531                       ce_same_name(ce, istate->cache[i+1]))
1532                        i++;
1533        }
1534        clear_pathspec(&revs->prune_data);
1535        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1536                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1537        revs->limited = 1;
1538}
1539
1540static int dotdot_missing(const char *arg, char *dotdot,
1541                          struct rev_info *revs, int symmetric)
1542{
1543        if (revs->ignore_missing)
1544                return 0;
1545        /* de-munge so we report the full argument */
1546        *dotdot = '.';
1547        die(symmetric
1548            ? "Invalid symmetric difference expression %s"
1549            : "Invalid revision range %s", arg);
1550}
1551
1552static int handle_dotdot_1(const char *arg, char *dotdot,
1553                           struct rev_info *revs, int flags,
1554                           int cant_be_filename,
1555                           struct object_context *a_oc,
1556                           struct object_context *b_oc)
1557{
1558        const char *a_name, *b_name;
1559        struct object_id a_oid, b_oid;
1560        struct object *a_obj, *b_obj;
1561        unsigned int a_flags, b_flags;
1562        int symmetric = 0;
1563        unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1564        unsigned int oc_flags = GET_OID_COMMITTISH | GET_OID_RECORD_PATH;
1565
1566        a_name = arg;
1567        if (!*a_name)
1568                a_name = "HEAD";
1569
1570        b_name = dotdot + 2;
1571        if (*b_name == '.') {
1572                symmetric = 1;
1573                b_name++;
1574        }
1575        if (!*b_name)
1576                b_name = "HEAD";
1577
1578        if (get_oid_with_context(a_name, oc_flags, &a_oid, a_oc) ||
1579            get_oid_with_context(b_name, oc_flags, &b_oid, b_oc))
1580                return -1;
1581
1582        if (!cant_be_filename) {
1583                *dotdot = '.';
1584                verify_non_filename(revs->prefix, arg);
1585                *dotdot = '\0';
1586        }
1587
1588        a_obj = parse_object(the_repository, &a_oid);
1589        b_obj = parse_object(the_repository, &b_oid);
1590        if (!a_obj || !b_obj)
1591                return dotdot_missing(arg, dotdot, revs, symmetric);
1592
1593        if (!symmetric) {
1594                /* just A..B */
1595                b_flags = flags;
1596                a_flags = flags_exclude;
1597        } else {
1598                /* A...B -- find merge bases between the two */
1599                struct commit *a, *b;
1600                struct commit_list *exclude;
1601
1602                a = lookup_commit_reference(the_repository, &a_obj->oid);
1603                b = lookup_commit_reference(the_repository, &b_obj->oid);
1604                if (!a || !b)
1605                        return dotdot_missing(arg, dotdot, revs, symmetric);
1606
1607                exclude = get_merge_bases(a, b);
1608                add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
1609                                     flags_exclude);
1610                add_pending_commit_list(revs, exclude, flags_exclude);
1611                free_commit_list(exclude);
1612
1613                b_flags = flags;
1614                a_flags = flags | SYMMETRIC_LEFT;
1615        }
1616
1617        a_obj->flags |= a_flags;
1618        b_obj->flags |= b_flags;
1619        add_rev_cmdline(revs, a_obj, a_name, REV_CMD_LEFT, a_flags);
1620        add_rev_cmdline(revs, b_obj, b_name, REV_CMD_RIGHT, b_flags);
1621        add_pending_object_with_path(revs, a_obj, a_name, a_oc->mode, a_oc->path);
1622        add_pending_object_with_path(revs, b_obj, b_name, b_oc->mode, b_oc->path);
1623        return 0;
1624}
1625
1626static int handle_dotdot(const char *arg,
1627                         struct rev_info *revs, int flags,
1628                         int cant_be_filename)
1629{
1630        struct object_context a_oc, b_oc;
1631        char *dotdot = strstr(arg, "..");
1632        int ret;
1633
1634        if (!dotdot)
1635                return -1;
1636
1637        memset(&a_oc, 0, sizeof(a_oc));
1638        memset(&b_oc, 0, sizeof(b_oc));
1639
1640        *dotdot = '\0';
1641        ret = handle_dotdot_1(arg, dotdot, revs, flags, cant_be_filename,
1642                              &a_oc, &b_oc);
1643        *dotdot = '.';
1644
1645        free(a_oc.path);
1646        free(b_oc.path);
1647
1648        return ret;
1649}
1650
1651int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1652{
1653        struct object_context oc;
1654        char *mark;
1655        struct object *object;
1656        struct object_id oid;
1657        int local_flags;
1658        const char *arg = arg_;
1659        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1660        unsigned get_sha1_flags = GET_OID_RECORD_PATH;
1661
1662        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1663
1664        if (!cant_be_filename && !strcmp(arg, "..")) {
1665                /*
1666                 * Just ".."?  That is not a range but the
1667                 * pathspec for the parent directory.
1668                 */
1669                return -1;
1670        }
1671
1672        if (!handle_dotdot(arg, revs, flags, revarg_opt))
1673                return 0;
1674
1675        mark = strstr(arg, "^@");
1676        if (mark && !mark[2]) {
1677                *mark = 0;
1678                if (add_parents_only(revs, arg, flags, 0))
1679                        return 0;
1680                *mark = '^';
1681        }
1682        mark = strstr(arg, "^!");
1683        if (mark && !mark[2]) {
1684                *mark = 0;
1685                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), 0))
1686                        *mark = '^';
1687        }
1688        mark = strstr(arg, "^-");
1689        if (mark) {
1690                int exclude_parent = 1;
1691
1692                if (mark[2]) {
1693                        char *end;
1694                        exclude_parent = strtoul(mark + 2, &end, 10);
1695                        if (*end != '\0' || !exclude_parent)
1696                                return -1;
1697                }
1698
1699                *mark = 0;
1700                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), exclude_parent))
1701                        *mark = '^';
1702        }
1703
1704        local_flags = 0;
1705        if (*arg == '^') {
1706                local_flags = UNINTERESTING | BOTTOM;
1707                arg++;
1708        }
1709
1710        if (revarg_opt & REVARG_COMMITTISH)
1711                get_sha1_flags |= GET_OID_COMMITTISH;
1712
1713        if (get_oid_with_context(arg, get_sha1_flags, &oid, &oc))
1714                return revs->ignore_missing ? 0 : -1;
1715        if (!cant_be_filename)
1716                verify_non_filename(revs->prefix, arg);
1717        object = get_reference(revs, arg, &oid, flags ^ local_flags);
1718        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1719        add_pending_object_with_path(revs, object, arg, oc.mode, oc.path);
1720        free(oc.path);
1721        return 0;
1722}
1723
1724static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1725                                     struct argv_array *prune)
1726{
1727        while (strbuf_getline(sb, stdin) != EOF)
1728                argv_array_push(prune, sb->buf);
1729}
1730
1731static void read_revisions_from_stdin(struct rev_info *revs,
1732                                      struct argv_array *prune)
1733{
1734        struct strbuf sb;
1735        int seen_dashdash = 0;
1736        int save_warning;
1737
1738        save_warning = warn_on_object_refname_ambiguity;
1739        warn_on_object_refname_ambiguity = 0;
1740
1741        strbuf_init(&sb, 1000);
1742        while (strbuf_getline(&sb, stdin) != EOF) {
1743                int len = sb.len;
1744                if (!len)
1745                        break;
1746                if (sb.buf[0] == '-') {
1747                        if (len == 2 && sb.buf[1] == '-') {
1748                                seen_dashdash = 1;
1749                                break;
1750                        }
1751                        die("options not supported in --stdin mode");
1752                }
1753                if (handle_revision_arg(sb.buf, revs, 0,
1754                                        REVARG_CANNOT_BE_FILENAME))
1755                        die("bad revision '%s'", sb.buf);
1756        }
1757        if (seen_dashdash)
1758                read_pathspec_from_stdin(revs, &sb, prune);
1759
1760        strbuf_release(&sb);
1761        warn_on_object_refname_ambiguity = save_warning;
1762}
1763
1764static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1765{
1766        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1767}
1768
1769static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1770{
1771        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1772}
1773
1774static void add_message_grep(struct rev_info *revs, const char *pattern)
1775{
1776        add_grep(revs, pattern, GREP_PATTERN_BODY);
1777}
1778
1779static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1780                               int *unkc, const char **unkv)
1781{
1782        const char *arg = argv[0];
1783        const char *optarg;
1784        int argcount;
1785        const unsigned hexsz = the_hash_algo->hexsz;
1786
1787        /* pseudo revision arguments */
1788        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1789            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1790            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1791            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1792            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1793            !strcmp(arg, "--indexed-objects") ||
1794            starts_with(arg, "--exclude=") ||
1795            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1796            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1797        {
1798                unkv[(*unkc)++] = arg;
1799                return 1;
1800        }
1801
1802        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1803                revs->max_count = atoi(optarg);
1804                revs->no_walk = 0;
1805                return argcount;
1806        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1807                revs->skip_count = atoi(optarg);
1808                return argcount;
1809        } else if ((*arg == '-') && isdigit(arg[1])) {
1810                /* accept -<digit>, like traditional "head" */
1811                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1812                    revs->max_count < 0)
1813                        die("'%s': not a non-negative integer", arg + 1);
1814                revs->no_walk = 0;
1815        } else if (!strcmp(arg, "-n")) {
1816                if (argc <= 1)
1817                        return error("-n requires an argument");
1818                revs->max_count = atoi(argv[1]);
1819                revs->no_walk = 0;
1820                return 2;
1821        } else if (skip_prefix(arg, "-n", &optarg)) {
1822                revs->max_count = atoi(optarg);
1823                revs->no_walk = 0;
1824        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1825                revs->max_age = atoi(optarg);
1826                return argcount;
1827        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1828                revs->max_age = approxidate(optarg);
1829                return argcount;
1830        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1831                revs->max_age = approxidate(optarg);
1832                return argcount;
1833        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1834                revs->min_age = atoi(optarg);
1835                return argcount;
1836        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1837                revs->min_age = approxidate(optarg);
1838                return argcount;
1839        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1840                revs->min_age = approxidate(optarg);
1841                return argcount;
1842        } else if (!strcmp(arg, "--first-parent")) {
1843                revs->first_parent_only = 1;
1844        } else if (!strcmp(arg, "--ancestry-path")) {
1845                revs->ancestry_path = 1;
1846                revs->simplify_history = 0;
1847                revs->limited = 1;
1848        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1849                init_reflog_walk(&revs->reflog_info);
1850        } else if (!strcmp(arg, "--default")) {
1851                if (argc <= 1)
1852                        return error("bad --default argument");
1853                revs->def = argv[1];
1854                return 2;
1855        } else if (!strcmp(arg, "--merge")) {
1856                revs->show_merge = 1;
1857        } else if (!strcmp(arg, "--topo-order")) {
1858                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1859                revs->topo_order = 1;
1860        } else if (!strcmp(arg, "--simplify-merges")) {
1861                revs->simplify_merges = 1;
1862                revs->topo_order = 1;
1863                revs->rewrite_parents = 1;
1864                revs->simplify_history = 0;
1865                revs->limited = 1;
1866        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1867                revs->simplify_merges = 1;
1868                revs->topo_order = 1;
1869                revs->rewrite_parents = 1;
1870                revs->simplify_history = 0;
1871                revs->simplify_by_decoration = 1;
1872                revs->limited = 1;
1873                revs->prune = 1;
1874                load_ref_decorations(NULL, DECORATE_SHORT_REFS);
1875        } else if (!strcmp(arg, "--date-order")) {
1876                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1877                revs->topo_order = 1;
1878        } else if (!strcmp(arg, "--author-date-order")) {
1879                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1880                revs->topo_order = 1;
1881        } else if (!strcmp(arg, "--early-output")) {
1882                revs->early_output = 100;
1883                revs->topo_order = 1;
1884        } else if (skip_prefix(arg, "--early-output=", &optarg)) {
1885                if (strtoul_ui(optarg, 10, &revs->early_output) < 0)
1886                        die("'%s': not a non-negative integer", optarg);
1887                revs->topo_order = 1;
1888        } else if (!strcmp(arg, "--parents")) {
1889                revs->rewrite_parents = 1;
1890                revs->print_parents = 1;
1891        } else if (!strcmp(arg, "--dense")) {
1892                revs->dense = 1;
1893        } else if (!strcmp(arg, "--sparse")) {
1894                revs->dense = 0;
1895        } else if (!strcmp(arg, "--in-commit-order")) {
1896                revs->tree_blobs_in_commit_order = 1;
1897        } else if (!strcmp(arg, "--remove-empty")) {
1898                revs->remove_empty_trees = 1;
1899        } else if (!strcmp(arg, "--merges")) {
1900                revs->min_parents = 2;
1901        } else if (!strcmp(arg, "--no-merges")) {
1902                revs->max_parents = 1;
1903        } else if (skip_prefix(arg, "--min-parents=", &optarg)) {
1904                revs->min_parents = atoi(optarg);
1905        } else if (!strcmp(arg, "--no-min-parents")) {
1906                revs->min_parents = 0;
1907        } else if (skip_prefix(arg, "--max-parents=", &optarg)) {
1908                revs->max_parents = atoi(optarg);
1909        } else if (!strcmp(arg, "--no-max-parents")) {
1910                revs->max_parents = -1;
1911        } else if (!strcmp(arg, "--boundary")) {
1912                revs->boundary = 1;
1913        } else if (!strcmp(arg, "--left-right")) {
1914                revs->left_right = 1;
1915        } else if (!strcmp(arg, "--left-only")) {
1916                if (revs->right_only)
1917                        die("--left-only is incompatible with --right-only"
1918                            " or --cherry");
1919                revs->left_only = 1;
1920        } else if (!strcmp(arg, "--right-only")) {
1921                if (revs->left_only)
1922                        die("--right-only is incompatible with --left-only");
1923                revs->right_only = 1;
1924        } else if (!strcmp(arg, "--cherry")) {
1925                if (revs->left_only)
1926                        die("--cherry is incompatible with --left-only");
1927                revs->cherry_mark = 1;
1928                revs->right_only = 1;
1929                revs->max_parents = 1;
1930                revs->limited = 1;
1931        } else if (!strcmp(arg, "--count")) {
1932                revs->count = 1;
1933        } else if (!strcmp(arg, "--cherry-mark")) {
1934                if (revs->cherry_pick)
1935                        die("--cherry-mark is incompatible with --cherry-pick");
1936                revs->cherry_mark = 1;
1937                revs->limited = 1; /* needs limit_list() */
1938        } else if (!strcmp(arg, "--cherry-pick")) {
1939                if (revs->cherry_mark)
1940                        die("--cherry-pick is incompatible with --cherry-mark");
1941                revs->cherry_pick = 1;
1942                revs->limited = 1;
1943        } else if (!strcmp(arg, "--objects")) {
1944                revs->tag_objects = 1;
1945                revs->tree_objects = 1;
1946                revs->blob_objects = 1;
1947        } else if (!strcmp(arg, "--objects-edge")) {
1948                revs->tag_objects = 1;
1949                revs->tree_objects = 1;
1950                revs->blob_objects = 1;
1951                revs->edge_hint = 1;
1952        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1953                revs->tag_objects = 1;
1954                revs->tree_objects = 1;
1955                revs->blob_objects = 1;
1956                revs->edge_hint = 1;
1957                revs->edge_hint_aggressive = 1;
1958        } else if (!strcmp(arg, "--verify-objects")) {
1959                revs->tag_objects = 1;
1960                revs->tree_objects = 1;
1961                revs->blob_objects = 1;
1962                revs->verify_objects = 1;
1963        } else if (!strcmp(arg, "--unpacked")) {
1964                revs->unpacked = 1;
1965        } else if (starts_with(arg, "--unpacked=")) {
1966                die("--unpacked=<packfile> no longer supported.");
1967        } else if (!strcmp(arg, "-r")) {
1968                revs->diff = 1;
1969                revs->diffopt.flags.recursive = 1;
1970        } else if (!strcmp(arg, "-t")) {
1971                revs->diff = 1;
1972                revs->diffopt.flags.recursive = 1;
1973                revs->diffopt.flags.tree_in_recursive = 1;
1974        } else if (!strcmp(arg, "-m")) {
1975                revs->ignore_merges = 0;
1976        } else if (!strcmp(arg, "-c")) {
1977                revs->diff = 1;
1978                revs->dense_combined_merges = 0;
1979                revs->combine_merges = 1;
1980        } else if (!strcmp(arg, "--cc")) {
1981                revs->diff = 1;
1982                revs->dense_combined_merges = 1;
1983                revs->combine_merges = 1;
1984        } else if (!strcmp(arg, "-v")) {
1985                revs->verbose_header = 1;
1986        } else if (!strcmp(arg, "--pretty")) {
1987                revs->verbose_header = 1;
1988                revs->pretty_given = 1;
1989                get_commit_format(NULL, revs);
1990        } else if (skip_prefix(arg, "--pretty=", &optarg) ||
1991                   skip_prefix(arg, "--format=", &optarg)) {
1992                /*
1993                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1994                 * not allowed, since the argument is optional.
1995                 */
1996                revs->verbose_header = 1;
1997                revs->pretty_given = 1;
1998                get_commit_format(optarg, revs);
1999        } else if (!strcmp(arg, "--expand-tabs")) {
2000                revs->expand_tabs_in_log = 8;
2001        } else if (!strcmp(arg, "--no-expand-tabs")) {
2002                revs->expand_tabs_in_log = 0;
2003        } else if (skip_prefix(arg, "--expand-tabs=", &arg)) {
2004                int val;
2005                if (strtol_i(arg, 10, &val) < 0 || val < 0)
2006                        die("'%s': not a non-negative integer", arg);
2007                revs->expand_tabs_in_log = val;
2008        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
2009                revs->show_notes = 1;
2010                revs->show_notes_given = 1;
2011                revs->notes_opt.use_default_notes = 1;
2012        } else if (!strcmp(arg, "--show-signature")) {
2013                revs->show_signature = 1;
2014        } else if (!strcmp(arg, "--no-show-signature")) {
2015                revs->show_signature = 0;
2016        } else if (!strcmp(arg, "--show-linear-break")) {
2017                revs->break_bar = "                    ..........";
2018                revs->track_linear = 1;
2019                revs->track_first_time = 1;
2020        } else if (skip_prefix(arg, "--show-linear-break=", &optarg)) {
2021                revs->break_bar = xstrdup(optarg);
2022                revs->track_linear = 1;
2023                revs->track_first_time = 1;
2024        } else if (skip_prefix(arg, "--show-notes=", &optarg) ||
2025                   skip_prefix(arg, "--notes=", &optarg)) {
2026                struct strbuf buf = STRBUF_INIT;
2027                revs->show_notes = 1;
2028                revs->show_notes_given = 1;
2029                if (starts_with(arg, "--show-notes=") &&
2030                    revs->notes_opt.use_default_notes < 0)
2031                        revs->notes_opt.use_default_notes = 1;
2032                strbuf_addstr(&buf, optarg);
2033                expand_notes_ref(&buf);
2034                string_list_append(&revs->notes_opt.extra_notes_refs,
2035                                   strbuf_detach(&buf, NULL));
2036        } else if (!strcmp(arg, "--no-notes")) {
2037                revs->show_notes = 0;
2038                revs->show_notes_given = 1;
2039                revs->notes_opt.use_default_notes = -1;
2040                /* we have been strdup'ing ourselves, so trick
2041                 * string_list into free()ing strings */
2042                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
2043                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
2044                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
2045        } else if (!strcmp(arg, "--standard-notes")) {
2046                revs->show_notes_given = 1;
2047                revs->notes_opt.use_default_notes = 1;
2048        } else if (!strcmp(arg, "--no-standard-notes")) {
2049                revs->notes_opt.use_default_notes = 0;
2050        } else if (!strcmp(arg, "--oneline")) {
2051                revs->verbose_header = 1;
2052                get_commit_format("oneline", revs);
2053                revs->pretty_given = 1;
2054                revs->abbrev_commit = 1;
2055        } else if (!strcmp(arg, "--graph")) {
2056                revs->topo_order = 1;
2057                revs->rewrite_parents = 1;
2058                revs->graph = graph_init(revs);
2059        } else if (!strcmp(arg, "--root")) {
2060                revs->show_root_diff = 1;
2061        } else if (!strcmp(arg, "--no-commit-id")) {
2062                revs->no_commit_id = 1;
2063        } else if (!strcmp(arg, "--always")) {
2064                revs->always_show_header = 1;
2065        } else if (!strcmp(arg, "--no-abbrev")) {
2066                revs->abbrev = 0;
2067        } else if (!strcmp(arg, "--abbrev")) {
2068                revs->abbrev = DEFAULT_ABBREV;
2069        } else if (skip_prefix(arg, "--abbrev=", &optarg)) {
2070                revs->abbrev = strtoul(optarg, NULL, 10);
2071                if (revs->abbrev < MINIMUM_ABBREV)
2072                        revs->abbrev = MINIMUM_ABBREV;
2073                else if (revs->abbrev > hexsz)
2074                        revs->abbrev = hexsz;
2075        } else if (!strcmp(arg, "--abbrev-commit")) {
2076                revs->abbrev_commit = 1;
2077                revs->abbrev_commit_given = 1;
2078        } else if (!strcmp(arg, "--no-abbrev-commit")) {
2079                revs->abbrev_commit = 0;
2080        } else if (!strcmp(arg, "--full-diff")) {
2081                revs->diff = 1;
2082                revs->full_diff = 1;
2083        } else if (!strcmp(arg, "--full-history")) {
2084                revs->simplify_history = 0;
2085        } else if (!strcmp(arg, "--relative-date")) {
2086                revs->date_mode.type = DATE_RELATIVE;
2087                revs->date_mode_explicit = 1;
2088        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
2089                parse_date_format(optarg, &revs->date_mode);
2090                revs->date_mode_explicit = 1;
2091                return argcount;
2092        } else if (!strcmp(arg, "--log-size")) {
2093                revs->show_log_size = 1;
2094        }
2095        /*
2096         * Grepping the commit log
2097         */
2098        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
2099                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
2100                return argcount;
2101        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
2102                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
2103                return argcount;
2104        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
2105                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
2106                return argcount;
2107        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
2108                add_message_grep(revs, optarg);
2109                return argcount;
2110        } else if (!strcmp(arg, "--grep-debug")) {
2111                revs->grep_filter.debug = 1;
2112        } else if (!strcmp(arg, "--basic-regexp")) {
2113                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_BRE;
2114        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
2115                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_ERE;
2116        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
2117                revs->grep_filter.ignore_case = 1;
2118                revs->diffopt.pickaxe_opts |= DIFF_PICKAXE_IGNORE_CASE;
2119        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
2120                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
2121        } else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
2122                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
2123        } else if (!strcmp(arg, "--all-match")) {
2124                revs->grep_filter.all_match = 1;
2125        } else if (!strcmp(arg, "--invert-grep")) {
2126                revs->invert_grep = 1;
2127        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
2128                if (strcmp(optarg, "none"))
2129                        git_log_output_encoding = xstrdup(optarg);
2130                else
2131                        git_log_output_encoding = "";
2132                return argcount;
2133        } else if (!strcmp(arg, "--reverse")) {
2134                revs->reverse ^= 1;
2135        } else if (!strcmp(arg, "--children")) {
2136                revs->children.name = "children";
2137                revs->limited = 1;
2138        } else if (!strcmp(arg, "--ignore-missing")) {
2139                revs->ignore_missing = 1;
2140        } else if (!strcmp(arg, "--exclude-promisor-objects")) {
2141                if (fetch_if_missing)
2142                        BUG("exclude_promisor_objects can only be used when fetch_if_missing is 0");
2143                revs->exclude_promisor_objects = 1;
2144        } else {
2145                int opts = diff_opt_parse(&revs->diffopt, argv, argc, revs->prefix);
2146                if (!opts)
2147                        unkv[(*unkc)++] = arg;
2148                return opts;
2149        }
2150        if (revs->graph && revs->track_linear)
2151                die("--show-linear-break and --graph are incompatible");
2152
2153        return 1;
2154}
2155
2156void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2157                        const struct option *options,
2158                        const char * const usagestr[])
2159{
2160        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2161                                    &ctx->cpidx, ctx->out);
2162        if (n <= 0) {
2163                error("unknown option `%s'", ctx->argv[0]);
2164                usage_with_options(usagestr, options);
2165        }
2166        ctx->argv += n;
2167        ctx->argc -= n;
2168}
2169
2170static int for_each_bisect_ref(struct ref_store *refs, each_ref_fn fn,
2171                               void *cb_data, const char *term)
2172{
2173        struct strbuf bisect_refs = STRBUF_INIT;
2174        int status;
2175        strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
2176        status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data, 0);
2177        strbuf_release(&bisect_refs);
2178        return status;
2179}
2180
2181static int for_each_bad_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2182{
2183        return for_each_bisect_ref(refs, fn, cb_data, term_bad);
2184}
2185
2186static int for_each_good_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2187{
2188        return for_each_bisect_ref(refs, fn, cb_data, term_good);
2189}
2190
2191static int handle_revision_pseudo_opt(const char *submodule,
2192                                struct rev_info *revs,
2193                                int argc, const char **argv, int *flags)
2194{
2195        const char *arg = argv[0];
2196        const char *optarg;
2197        struct ref_store *refs;
2198        int argcount;
2199
2200        if (submodule) {
2201                /*
2202                 * We need some something like get_submodule_worktrees()
2203                 * before we can go through all worktrees of a submodule,
2204                 * .e.g with adding all HEADs from --all, which is not
2205                 * supported right now, so stick to single worktree.
2206                 */
2207                if (!revs->single_worktree)
2208                        BUG("--single-worktree cannot be used together with submodule");
2209                refs = get_submodule_ref_store(submodule);
2210        } else
2211                refs = get_main_ref_store(the_repository);
2212
2213        /*
2214         * NOTE!
2215         *
2216         * Commands like "git shortlog" will not accept the options below
2217         * unless parse_revision_opt queues them (as opposed to erroring
2218         * out).
2219         *
2220         * When implementing your new pseudo-option, remember to
2221         * register it in the list at the top of handle_revision_opt.
2222         */
2223        if (!strcmp(arg, "--all")) {
2224                handle_refs(refs, revs, *flags, refs_for_each_ref);
2225                handle_refs(refs, revs, *flags, refs_head_ref);
2226                if (!revs->single_worktree) {
2227                        struct all_refs_cb cb;
2228
2229                        init_all_refs_cb(&cb, revs, *flags);
2230                        other_head_refs(handle_one_ref, &cb);
2231                }
2232                clear_ref_exclusion(&revs->ref_excludes);
2233        } else if (!strcmp(arg, "--branches")) {
2234                handle_refs(refs, revs, *flags, refs_for_each_branch_ref);
2235                clear_ref_exclusion(&revs->ref_excludes);
2236        } else if (!strcmp(arg, "--bisect")) {
2237                read_bisect_terms(&term_bad, &term_good);
2238                handle_refs(refs, revs, *flags, for_each_bad_bisect_ref);
2239                handle_refs(refs, revs, *flags ^ (UNINTERESTING | BOTTOM),
2240                            for_each_good_bisect_ref);
2241                revs->bisect = 1;
2242        } else if (!strcmp(arg, "--tags")) {
2243                handle_refs(refs, revs, *flags, refs_for_each_tag_ref);
2244                clear_ref_exclusion(&revs->ref_excludes);
2245        } else if (!strcmp(arg, "--remotes")) {
2246                handle_refs(refs, revs, *flags, refs_for_each_remote_ref);
2247                clear_ref_exclusion(&revs->ref_excludes);
2248        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2249                struct all_refs_cb cb;
2250                init_all_refs_cb(&cb, revs, *flags);
2251                for_each_glob_ref(handle_one_ref, optarg, &cb);
2252                clear_ref_exclusion(&revs->ref_excludes);
2253                return argcount;
2254        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2255                add_ref_exclusion(&revs->ref_excludes, optarg);
2256                return argcount;
2257        } else if (skip_prefix(arg, "--branches=", &optarg)) {
2258                struct all_refs_cb cb;
2259                init_all_refs_cb(&cb, revs, *flags);
2260                for_each_glob_ref_in(handle_one_ref, optarg, "refs/heads/", &cb);
2261                clear_ref_exclusion(&revs->ref_excludes);
2262        } else if (skip_prefix(arg, "--tags=", &optarg)) {
2263                struct all_refs_cb cb;
2264                init_all_refs_cb(&cb, revs, *flags);
2265                for_each_glob_ref_in(handle_one_ref, optarg, "refs/tags/", &cb);
2266                clear_ref_exclusion(&revs->ref_excludes);
2267        } else if (skip_prefix(arg, "--remotes=", &optarg)) {
2268                struct all_refs_cb cb;
2269                init_all_refs_cb(&cb, revs, *flags);
2270                for_each_glob_ref_in(handle_one_ref, optarg, "refs/remotes/", &cb);
2271                clear_ref_exclusion(&revs->ref_excludes);
2272        } else if (!strcmp(arg, "--reflog")) {
2273                add_reflogs_to_pending(revs, *flags);
2274        } else if (!strcmp(arg, "--indexed-objects")) {
2275                add_index_objects_to_pending(revs, *flags);
2276        } else if (!strcmp(arg, "--not")) {
2277                *flags ^= UNINTERESTING | BOTTOM;
2278        } else if (!strcmp(arg, "--no-walk")) {
2279                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2280        } else if (skip_prefix(arg, "--no-walk=", &optarg)) {
2281                /*
2282                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2283                 * not allowed, since the argument is optional.
2284                 */
2285                if (!strcmp(optarg, "sorted"))
2286                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2287                else if (!strcmp(optarg, "unsorted"))
2288                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2289                else
2290                        return error("invalid argument to --no-walk");
2291        } else if (!strcmp(arg, "--do-walk")) {
2292                revs->no_walk = 0;
2293        } else if (!strcmp(arg, "--single-worktree")) {
2294                revs->single_worktree = 1;
2295        } else {
2296                return 0;
2297        }
2298
2299        return 1;
2300}
2301
2302static void NORETURN diagnose_missing_default(const char *def)
2303{
2304        int flags;
2305        const char *refname;
2306
2307        refname = resolve_ref_unsafe(def, 0, NULL, &flags);
2308        if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
2309                die(_("your current branch appears to be broken"));
2310
2311        skip_prefix(refname, "refs/heads/", &refname);
2312        die(_("your current branch '%s' does not have any commits yet"),
2313            refname);
2314}
2315
2316/*
2317 * Parse revision information, filling in the "rev_info" structure,
2318 * and removing the used arguments from the argument list.
2319 *
2320 * Returns the number of arguments left that weren't recognized
2321 * (which are also moved to the head of the argument list)
2322 */
2323int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2324{
2325        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2326        struct argv_array prune_data = ARGV_ARRAY_INIT;
2327        const char *submodule = NULL;
2328
2329        if (opt)
2330                submodule = opt->submodule;
2331
2332        /* First, search for "--" */
2333        if (opt && opt->assume_dashdash) {
2334                seen_dashdash = 1;
2335        } else {
2336                seen_dashdash = 0;
2337                for (i = 1; i < argc; i++) {
2338                        const char *arg = argv[i];
2339                        if (strcmp(arg, "--"))
2340                                continue;
2341                        argv[i] = NULL;
2342                        argc = i;
2343                        if (argv[i + 1])
2344                                argv_array_pushv(&prune_data, argv + i + 1);
2345                        seen_dashdash = 1;
2346                        break;
2347                }
2348        }
2349
2350        /* Second, deal with arguments and options */
2351        flags = 0;
2352        revarg_opt = opt ? opt->revarg_opt : 0;
2353        if (seen_dashdash)
2354                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2355        read_from_stdin = 0;
2356        for (left = i = 1; i < argc; i++) {
2357                const char *arg = argv[i];
2358                if (*arg == '-') {
2359                        int opts;
2360
2361                        opts = handle_revision_pseudo_opt(submodule,
2362                                                revs, argc - i, argv + i,
2363                                                &flags);
2364                        if (opts > 0) {
2365                                i += opts - 1;
2366                                continue;
2367                        }
2368
2369                        if (!strcmp(arg, "--stdin")) {
2370                                if (revs->disable_stdin) {
2371                                        argv[left++] = arg;
2372                                        continue;
2373                                }
2374                                if (read_from_stdin++)
2375                                        die("--stdin given twice?");
2376                                read_revisions_from_stdin(revs, &prune_data);
2377                                continue;
2378                        }
2379
2380                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2381                        if (opts > 0) {
2382                                i += opts - 1;
2383                                continue;
2384                        }
2385                        if (opts < 0)
2386                                exit(128);
2387                        continue;
2388                }
2389
2390
2391                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2392                        int j;
2393                        if (seen_dashdash || *arg == '^')
2394                                die("bad revision '%s'", arg);
2395
2396                        /* If we didn't have a "--":
2397                         * (1) all filenames must exist;
2398                         * (2) all rev-args must not be interpretable
2399                         *     as a valid filename.
2400                         * but the latter we have checked in the main loop.
2401                         */
2402                        for (j = i; j < argc; j++)
2403                                verify_filename(revs->prefix, argv[j], j == i);
2404
2405                        argv_array_pushv(&prune_data, argv + i);
2406                        break;
2407                }
2408                else
2409                        got_rev_arg = 1;
2410        }
2411
2412        if (prune_data.argc) {
2413                /*
2414                 * If we need to introduce the magic "a lone ':' means no
2415                 * pathspec whatsoever", here is the place to do so.
2416                 *
2417                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2418                 *      prune_data.nr = 0;
2419                 *      prune_data.alloc = 0;
2420                 *      free(prune_data.path);
2421                 *      prune_data.path = NULL;
2422                 * } else {
2423                 *      terminate prune_data.alloc with NULL and
2424                 *      call init_pathspec() to set revs->prune_data here.
2425                 * }
2426                 */
2427                parse_pathspec(&revs->prune_data, 0, 0,
2428                               revs->prefix, prune_data.argv);
2429        }
2430        argv_array_clear(&prune_data);
2431
2432        if (revs->def == NULL)
2433                revs->def = opt ? opt->def : NULL;
2434        if (opt && opt->tweak)
2435                opt->tweak(revs, opt);
2436        if (revs->show_merge)
2437                prepare_show_merge(revs);
2438        if (revs->def && !revs->pending.nr && !revs->rev_input_given && !got_rev_arg) {
2439                struct object_id oid;
2440                struct object *object;
2441                struct object_context oc;
2442                if (get_oid_with_context(revs->def, 0, &oid, &oc))
2443                        diagnose_missing_default(revs->def);
2444                object = get_reference(revs, revs->def, &oid, 0);
2445                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2446        }
2447
2448        /* Did the user ask for any diff output? Run the diff! */
2449        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2450                revs->diff = 1;
2451
2452        /* Pickaxe, diff-filter and rename following need diffs */
2453        if ((revs->diffopt.pickaxe_opts & DIFF_PICKAXE_KINDS_MASK) ||
2454            revs->diffopt.filter ||
2455            revs->diffopt.flags.follow_renames)
2456                revs->diff = 1;
2457
2458        if (revs->diffopt.objfind)
2459                revs->simplify_history = 0;
2460
2461        if (revs->topo_order)
2462                revs->limited = 1;
2463
2464        if (revs->prune_data.nr) {
2465                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2466                /* Can't prune commits with rename following: the paths change.. */
2467                if (!revs->diffopt.flags.follow_renames)
2468                        revs->prune = 1;
2469                if (!revs->full_diff)
2470                        copy_pathspec(&revs->diffopt.pathspec,
2471                                      &revs->prune_data);
2472        }
2473        if (revs->combine_merges)
2474                revs->ignore_merges = 0;
2475        revs->diffopt.abbrev = revs->abbrev;
2476
2477        if (revs->line_level_traverse) {
2478                revs->limited = 1;
2479                revs->topo_order = 1;
2480        }
2481
2482        diff_setup_done(&revs->diffopt);
2483
2484        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2485                                 &revs->grep_filter);
2486        compile_grep_patterns(&revs->grep_filter);
2487
2488        if (revs->reverse && revs->reflog_info)
2489                die("cannot combine --reverse with --walk-reflogs");
2490        if (revs->reflog_info && revs->limited)
2491                die("cannot combine --walk-reflogs with history-limiting options");
2492        if (revs->rewrite_parents && revs->children.name)
2493                die("cannot combine --parents and --children");
2494
2495        /*
2496         * Limitations on the graph functionality
2497         */
2498        if (revs->reverse && revs->graph)
2499                die("cannot combine --reverse with --graph");
2500
2501        if (revs->reflog_info && revs->graph)
2502                die("cannot combine --walk-reflogs with --graph");
2503        if (revs->no_walk && revs->graph)
2504                die("cannot combine --no-walk with --graph");
2505        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2506                die("cannot use --grep-reflog without --walk-reflogs");
2507
2508        if (revs->first_parent_only && revs->bisect)
2509                die(_("--first-parent is incompatible with --bisect"));
2510
2511        if (revs->expand_tabs_in_log < 0)
2512                revs->expand_tabs_in_log = revs->expand_tabs_in_log_default;
2513
2514        return left;
2515}
2516
2517static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2518{
2519        struct commit_list *l = xcalloc(1, sizeof(*l));
2520
2521        l->item = child;
2522        l->next = add_decoration(&revs->children, &parent->object, l);
2523}
2524
2525static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2526{
2527        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2528        struct commit_list **pp, *p;
2529        int surviving_parents;
2530
2531        /* Examine existing parents while marking ones we have seen... */
2532        pp = &commit->parents;
2533        surviving_parents = 0;
2534        while ((p = *pp) != NULL) {
2535                struct commit *parent = p->item;
2536                if (parent->object.flags & TMP_MARK) {
2537                        *pp = p->next;
2538                        if (ts)
2539                                compact_treesame(revs, commit, surviving_parents);
2540                        continue;
2541                }
2542                parent->object.flags |= TMP_MARK;
2543                surviving_parents++;
2544                pp = &p->next;
2545        }
2546        /* clear the temporary mark */
2547        for (p = commit->parents; p; p = p->next) {
2548                p->item->object.flags &= ~TMP_MARK;
2549        }
2550        /* no update_treesame() - removing duplicates can't affect TREESAME */
2551        return surviving_parents;
2552}
2553
2554struct merge_simplify_state {
2555        struct commit *simplified;
2556};
2557
2558static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2559{
2560        struct merge_simplify_state *st;
2561
2562        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2563        if (!st) {
2564                st = xcalloc(1, sizeof(*st));
2565                add_decoration(&revs->merge_simplification, &commit->object, st);
2566        }
2567        return st;
2568}
2569
2570static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2571{
2572        struct commit_list *h = reduce_heads(commit->parents);
2573        int i = 0, marked = 0;
2574        struct commit_list *po, *pn;
2575
2576        /* Want these for sanity-checking only */
2577        int orig_cnt = commit_list_count(commit->parents);
2578        int cnt = commit_list_count(h);
2579
2580        /*
2581         * Not ready to remove items yet, just mark them for now, based
2582         * on the output of reduce_heads(). reduce_heads outputs the reduced
2583         * set in its original order, so this isn't too hard.
2584         */
2585        po = commit->parents;
2586        pn = h;
2587        while (po) {
2588                if (pn && po->item == pn->item) {
2589                        pn = pn->next;
2590                        i++;
2591                } else {
2592                        po->item->object.flags |= TMP_MARK;
2593                        marked++;
2594                }
2595                po=po->next;
2596        }
2597
2598        if (i != cnt || cnt+marked != orig_cnt)
2599                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2600
2601        free_commit_list(h);
2602
2603        return marked;
2604}
2605
2606static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2607{
2608        struct commit_list *p;
2609        int marked = 0;
2610
2611        for (p = commit->parents; p; p = p->next) {
2612                struct commit *parent = p->item;
2613                if (!parent->parents && (parent->object.flags & TREESAME)) {
2614                        parent->object.flags |= TMP_MARK;
2615                        marked++;
2616                }
2617        }
2618
2619        return marked;
2620}
2621
2622/*
2623 * Awkward naming - this means one parent we are TREESAME to.
2624 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2625 * empty tree). Better name suggestions?
2626 */
2627static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2628{
2629        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2630        struct commit *unmarked = NULL, *marked = NULL;
2631        struct commit_list *p;
2632        unsigned n;
2633
2634        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2635                if (ts->treesame[n]) {
2636                        if (p->item->object.flags & TMP_MARK) {
2637                                if (!marked)
2638                                        marked = p->item;
2639                        } else {
2640                                if (!unmarked) {
2641                                        unmarked = p->item;
2642                                        break;
2643                                }
2644                        }
2645                }
2646        }
2647
2648        /*
2649         * If we are TREESAME to a marked-for-deletion parent, but not to any
2650         * unmarked parents, unmark the first TREESAME parent. This is the
2651         * parent that the default simplify_history==1 scan would have followed,
2652         * and it doesn't make sense to omit that path when asking for a
2653         * simplified full history. Retaining it improves the chances of
2654         * understanding odd missed merges that took an old version of a file.
2655         *
2656         * Example:
2657         *
2658         *   I--------*X       A modified the file, but mainline merge X used
2659         *    \       /        "-s ours", so took the version from I. X is
2660         *     `-*A--'         TREESAME to I and !TREESAME to A.
2661         *
2662         * Default log from X would produce "I". Without this check,
2663         * --full-history --simplify-merges would produce "I-A-X", showing
2664         * the merge commit X and that it changed A, but not making clear that
2665         * it had just taken the I version. With this check, the topology above
2666         * is retained.
2667         *
2668         * Note that it is possible that the simplification chooses a different
2669         * TREESAME parent from the default, in which case this test doesn't
2670         * activate, and we _do_ drop the default parent. Example:
2671         *
2672         *   I------X         A modified the file, but it was reverted in B,
2673         *    \    /          meaning mainline merge X is TREESAME to both
2674         *    *A-*B           parents.
2675         *
2676         * Default log would produce "I" by following the first parent;
2677         * --full-history --simplify-merges will produce "I-A-B". But this is a
2678         * reasonable result - it presents a logical full history leading from
2679         * I to X, and X is not an important merge.
2680         */
2681        if (!unmarked && marked) {
2682                marked->object.flags &= ~TMP_MARK;
2683                return 1;
2684        }
2685
2686        return 0;
2687}
2688
2689static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2690{
2691        struct commit_list **pp, *p;
2692        int nth_parent, removed = 0;
2693
2694        pp = &commit->parents;
2695        nth_parent = 0;
2696        while ((p = *pp) != NULL) {
2697                struct commit *parent = p->item;
2698                if (parent->object.flags & TMP_MARK) {
2699                        parent->object.flags &= ~TMP_MARK;
2700                        *pp = p->next;
2701                        free(p);
2702                        removed++;
2703                        compact_treesame(revs, commit, nth_parent);
2704                        continue;
2705                }
2706                pp = &p->next;
2707                nth_parent++;
2708        }
2709
2710        /* Removing parents can only increase TREESAMEness */
2711        if (removed && !(commit->object.flags & TREESAME))
2712                update_treesame(revs, commit);
2713
2714        return nth_parent;
2715}
2716
2717static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2718{
2719        struct commit_list *p;
2720        struct commit *parent;
2721        struct merge_simplify_state *st, *pst;
2722        int cnt;
2723
2724        st = locate_simplify_state(revs, commit);
2725
2726        /*
2727         * Have we handled this one?
2728         */
2729        if (st->simplified)
2730                return tail;
2731
2732        /*
2733         * An UNINTERESTING commit simplifies to itself, so does a
2734         * root commit.  We do not rewrite parents of such commit
2735         * anyway.
2736         */
2737        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2738                st->simplified = commit;
2739                return tail;
2740        }
2741
2742        /*
2743         * Do we know what commit all of our parents that matter
2744         * should be rewritten to?  Otherwise we are not ready to
2745         * rewrite this one yet.
2746         */
2747        for (cnt = 0, p = commit->parents; p; p = p->next) {
2748                pst = locate_simplify_state(revs, p->item);
2749                if (!pst->simplified) {
2750                        tail = &commit_list_insert(p->item, tail)->next;
2751                        cnt++;
2752                }
2753                if (revs->first_parent_only)
2754                        break;
2755        }
2756        if (cnt) {
2757                tail = &commit_list_insert(commit, tail)->next;
2758                return tail;
2759        }
2760
2761        /*
2762         * Rewrite our list of parents. Note that this cannot
2763         * affect our TREESAME flags in any way - a commit is
2764         * always TREESAME to its simplification.
2765         */
2766        for (p = commit->parents; p; p = p->next) {
2767                pst = locate_simplify_state(revs, p->item);
2768                p->item = pst->simplified;
2769                if (revs->first_parent_only)
2770                        break;
2771        }
2772
2773        if (revs->first_parent_only)
2774                cnt = 1;
2775        else
2776                cnt = remove_duplicate_parents(revs, commit);
2777
2778        /*
2779         * It is possible that we are a merge and one side branch
2780         * does not have any commit that touches the given paths;
2781         * in such a case, the immediate parent from that branch
2782         * will be rewritten to be the merge base.
2783         *
2784         *      o----X          X: the commit we are looking at;
2785         *     /    /           o: a commit that touches the paths;
2786         * ---o----'
2787         *
2788         * Further, a merge of an independent branch that doesn't
2789         * touch the path will reduce to a treesame root parent:
2790         *
2791         *  ----o----X          X: the commit we are looking at;
2792         *          /           o: a commit that touches the paths;
2793         *         r            r: a root commit not touching the paths
2794         *
2795         * Detect and simplify both cases.
2796         */
2797        if (1 < cnt) {
2798                int marked = mark_redundant_parents(revs, commit);
2799                marked += mark_treesame_root_parents(revs, commit);
2800                if (marked)
2801                        marked -= leave_one_treesame_to_parent(revs, commit);
2802                if (marked)
2803                        cnt = remove_marked_parents(revs, commit);
2804        }
2805
2806        /*
2807         * A commit simplifies to itself if it is a root, if it is
2808         * UNINTERESTING, if it touches the given paths, or if it is a
2809         * merge and its parents don't simplify to one relevant commit
2810         * (the first two cases are already handled at the beginning of
2811         * this function).
2812         *
2813         * Otherwise, it simplifies to what its sole relevant parent
2814         * simplifies to.
2815         */
2816        if (!cnt ||
2817            (commit->object.flags & UNINTERESTING) ||
2818            !(commit->object.flags & TREESAME) ||
2819            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2820                st->simplified = commit;
2821        else {
2822                pst = locate_simplify_state(revs, parent);
2823                st->simplified = pst->simplified;
2824        }
2825        return tail;
2826}
2827
2828static void simplify_merges(struct rev_info *revs)
2829{
2830        struct commit_list *list, *next;
2831        struct commit_list *yet_to_do, **tail;
2832        struct commit *commit;
2833
2834        if (!revs->prune)
2835                return;
2836
2837        /* feed the list reversed */
2838        yet_to_do = NULL;
2839        for (list = revs->commits; list; list = next) {
2840                commit = list->item;
2841                next = list->next;
2842                /*
2843                 * Do not free(list) here yet; the original list
2844                 * is used later in this function.
2845                 */
2846                commit_list_insert(commit, &yet_to_do);
2847        }
2848        while (yet_to_do) {
2849                list = yet_to_do;
2850                yet_to_do = NULL;
2851                tail = &yet_to_do;
2852                while (list) {
2853                        commit = pop_commit(&list);
2854                        tail = simplify_one(revs, commit, tail);
2855                }
2856        }
2857
2858        /* clean up the result, removing the simplified ones */
2859        list = revs->commits;
2860        revs->commits = NULL;
2861        tail = &revs->commits;
2862        while (list) {
2863                struct merge_simplify_state *st;
2864
2865                commit = pop_commit(&list);
2866                st = locate_simplify_state(revs, commit);
2867                if (st->simplified == commit)
2868                        tail = &commit_list_insert(commit, tail)->next;
2869        }
2870}
2871
2872static void set_children(struct rev_info *revs)
2873{
2874        struct commit_list *l;
2875        for (l = revs->commits; l; l = l->next) {
2876                struct commit *commit = l->item;
2877                struct commit_list *p;
2878
2879                for (p = commit->parents; p; p = p->next)
2880                        add_child(revs, p->item, commit);
2881        }
2882}
2883
2884void reset_revision_walk(void)
2885{
2886        clear_object_flags(SEEN | ADDED | SHOWN);
2887}
2888
2889static int mark_uninteresting(const struct object_id *oid,
2890                              struct packed_git *pack,
2891                              uint32_t pos,
2892                              void *unused)
2893{
2894        struct object *o = parse_object(the_repository, oid);
2895        o->flags |= UNINTERESTING | SEEN;
2896        return 0;
2897}
2898
2899int prepare_revision_walk(struct rev_info *revs)
2900{
2901        int i;
2902        struct object_array old_pending;
2903        struct commit_list **next = &revs->commits;
2904
2905        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2906        revs->pending.nr = 0;
2907        revs->pending.alloc = 0;
2908        revs->pending.objects = NULL;
2909        for (i = 0; i < old_pending.nr; i++) {
2910                struct object_array_entry *e = old_pending.objects + i;
2911                struct commit *commit = handle_commit(revs, e);
2912                if (commit) {
2913                        if (!(commit->object.flags & SEEN)) {
2914                                commit->object.flags |= SEEN;
2915                                next = commit_list_append(commit, next);
2916                        }
2917                }
2918        }
2919        object_array_clear(&old_pending);
2920
2921        /* Signal whether we need per-parent treesame decoration */
2922        if (revs->simplify_merges ||
2923            (revs->limited && limiting_can_increase_treesame(revs)))
2924                revs->treesame.name = "treesame";
2925
2926        if (revs->exclude_promisor_objects) {
2927                for_each_packed_object(mark_uninteresting, NULL,
2928                                       FOR_EACH_OBJECT_PROMISOR_ONLY);
2929        }
2930
2931        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2932                commit_list_sort_by_date(&revs->commits);
2933        if (revs->no_walk)
2934                return 0;
2935        if (revs->limited)
2936                if (limit_list(revs) < 0)
2937                        return -1;
2938        if (revs->topo_order)
2939                sort_in_topological_order(&revs->commits, revs->sort_order);
2940        if (revs->line_level_traverse)
2941                line_log_filter(revs);
2942        if (revs->simplify_merges)
2943                simplify_merges(revs);
2944        if (revs->children.name)
2945                set_children(revs);
2946        return 0;
2947}
2948
2949static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2950{
2951        struct commit_list *cache = NULL;
2952
2953        for (;;) {
2954                struct commit *p = *pp;
2955                if (!revs->limited)
2956                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2957                                return rewrite_one_error;
2958                if (p->object.flags & UNINTERESTING)
2959                        return rewrite_one_ok;
2960                if (!(p->object.flags & TREESAME))
2961                        return rewrite_one_ok;
2962                if (!p->parents)
2963                        return rewrite_one_noparents;
2964                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2965                        return rewrite_one_ok;
2966                *pp = p;
2967        }
2968}
2969
2970int rewrite_parents(struct rev_info *revs, struct commit *commit,
2971        rewrite_parent_fn_t rewrite_parent)
2972{
2973        struct commit_list **pp = &commit->parents;
2974        while (*pp) {
2975                struct commit_list *parent = *pp;
2976                switch (rewrite_parent(revs, &parent->item)) {
2977                case rewrite_one_ok:
2978                        break;
2979                case rewrite_one_noparents:
2980                        *pp = parent->next;
2981                        continue;
2982                case rewrite_one_error:
2983                        return -1;
2984                }
2985                pp = &parent->next;
2986        }
2987        remove_duplicate_parents(revs, commit);
2988        return 0;
2989}
2990
2991static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2992{
2993        char *person, *endp;
2994        size_t len, namelen, maillen;
2995        const char *name;
2996        const char *mail;
2997        struct ident_split ident;
2998
2999        person = strstr(buf->buf, what);
3000        if (!person)
3001                return 0;
3002
3003        person += strlen(what);
3004        endp = strchr(person, '\n');
3005        if (!endp)
3006                return 0;
3007
3008        len = endp - person;
3009
3010        if (split_ident_line(&ident, person, len))
3011                return 0;
3012
3013        mail = ident.mail_begin;
3014        maillen = ident.mail_end - ident.mail_begin;
3015        name = ident.name_begin;
3016        namelen = ident.name_end - ident.name_begin;
3017
3018        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
3019                struct strbuf namemail = STRBUF_INIT;
3020
3021                strbuf_addf(&namemail, "%.*s <%.*s>",
3022                            (int)namelen, name, (int)maillen, mail);
3023
3024                strbuf_splice(buf, ident.name_begin - buf->buf,
3025                              ident.mail_end - ident.name_begin + 1,
3026                              namemail.buf, namemail.len);
3027
3028                strbuf_release(&namemail);
3029
3030                return 1;
3031        }
3032
3033        return 0;
3034}
3035
3036static int commit_match(struct commit *commit, struct rev_info *opt)
3037{
3038        int retval;
3039        const char *encoding;
3040        const char *message;
3041        struct strbuf buf = STRBUF_INIT;
3042
3043        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
3044                return 1;
3045
3046        /* Prepend "fake" headers as needed */
3047        if (opt->grep_filter.use_reflog_filter) {
3048                strbuf_addstr(&buf, "reflog ");
3049                get_reflog_message(&buf, opt->reflog_info);
3050                strbuf_addch(&buf, '\n');
3051        }
3052
3053        /*
3054         * We grep in the user's output encoding, under the assumption that it
3055         * is the encoding they are most likely to write their grep pattern
3056         * for. In addition, it means we will match the "notes" encoding below,
3057         * so we will not end up with a buffer that has two different encodings
3058         * in it.
3059         */
3060        encoding = get_log_output_encoding();
3061        message = logmsg_reencode(commit, NULL, encoding);
3062
3063        /* Copy the commit to temporary if we are using "fake" headers */
3064        if (buf.len)
3065                strbuf_addstr(&buf, message);
3066
3067        if (opt->grep_filter.header_list && opt->mailmap) {
3068                if (!buf.len)
3069                        strbuf_addstr(&buf, message);
3070
3071                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
3072                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
3073        }
3074
3075        /* Append "fake" message parts as needed */
3076        if (opt->show_notes) {
3077                if (!buf.len)
3078                        strbuf_addstr(&buf, message);
3079                format_display_notes(&commit->object.oid, &buf, encoding, 1);
3080        }
3081
3082        /*
3083         * Find either in the original commit message, or in the temporary.
3084         * Note that we cast away the constness of "message" here. It is
3085         * const because it may come from the cached commit buffer. That's OK,
3086         * because we know that it is modifiable heap memory, and that while
3087         * grep_buffer may modify it for speed, it will restore any
3088         * changes before returning.
3089         */
3090        if (buf.len)
3091                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
3092        else
3093                retval = grep_buffer(&opt->grep_filter,
3094                                     (char *)message, strlen(message));
3095        strbuf_release(&buf);
3096        unuse_commit_buffer(commit, message);
3097        return opt->invert_grep ? !retval : retval;
3098}
3099
3100static inline int want_ancestry(const struct rev_info *revs)
3101{
3102        return (revs->rewrite_parents || revs->children.name);
3103}
3104
3105/*
3106 * Return a timestamp to be used for --since/--until comparisons for this
3107 * commit, based on the revision options.
3108 */
3109static timestamp_t comparison_date(const struct rev_info *revs,
3110                                   struct commit *commit)
3111{
3112        return revs->reflog_info ?
3113                get_reflog_timestamp(revs->reflog_info) :
3114                commit->date;
3115}
3116
3117enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
3118{
3119        if (commit->object.flags & SHOWN)
3120                return commit_ignore;
3121        if (revs->unpacked && has_object_pack(&commit->object.oid))
3122                return commit_ignore;
3123        if (commit->object.flags & UNINTERESTING)
3124                return commit_ignore;
3125        if (revs->min_age != -1 &&
3126            comparison_date(revs, commit) > revs->min_age)
3127                        return commit_ignore;
3128        if (revs->min_parents || (revs->max_parents >= 0)) {
3129                int n = commit_list_count(commit->parents);
3130                if ((n < revs->min_parents) ||
3131                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
3132                        return commit_ignore;
3133        }
3134        if (!commit_match(commit, revs))
3135                return commit_ignore;
3136        if (revs->prune && revs->dense) {
3137                /* Commit without changes? */
3138                if (commit->object.flags & TREESAME) {
3139                        int n;
3140                        struct commit_list *p;
3141                        /* drop merges unless we want parenthood */
3142                        if (!want_ancestry(revs))
3143                                return commit_ignore;
3144                        /*
3145                         * If we want ancestry, then need to keep any merges
3146                         * between relevant commits to tie together topology.
3147                         * For consistency with TREESAME and simplification
3148                         * use "relevant" here rather than just INTERESTING,
3149                         * to treat bottom commit(s) as part of the topology.
3150                         */
3151                        for (n = 0, p = commit->parents; p; p = p->next)
3152                                if (relevant_commit(p->item))
3153                                        if (++n >= 2)
3154                                                return commit_show;
3155                        return commit_ignore;
3156                }
3157        }
3158        return commit_show;
3159}
3160
3161define_commit_slab(saved_parents, struct commit_list *);
3162
3163#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
3164
3165/*
3166 * You may only call save_parents() once per commit (this is checked
3167 * for non-root commits).
3168 */
3169static void save_parents(struct rev_info *revs, struct commit *commit)
3170{
3171        struct commit_list **pp;
3172
3173        if (!revs->saved_parents_slab) {
3174                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
3175                init_saved_parents(revs->saved_parents_slab);
3176        }
3177
3178        pp = saved_parents_at(revs->saved_parents_slab, commit);
3179
3180        /*
3181         * When walking with reflogs, we may visit the same commit
3182         * several times: once for each appearance in the reflog.
3183         *
3184         * In this case, save_parents() will be called multiple times.
3185         * We want to keep only the first set of parents.  We need to
3186         * store a sentinel value for an empty (i.e., NULL) parent
3187         * list to distinguish it from a not-yet-saved list, however.
3188         */
3189        if (*pp)
3190                return;
3191        if (commit->parents)
3192                *pp = copy_commit_list(commit->parents);
3193        else
3194                *pp = EMPTY_PARENT_LIST;
3195}
3196
3197static void free_saved_parents(struct rev_info *revs)
3198{
3199        if (revs->saved_parents_slab)
3200                clear_saved_parents(revs->saved_parents_slab);
3201}
3202
3203struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
3204{
3205        struct commit_list *parents;
3206
3207        if (!revs->saved_parents_slab)
3208                return commit->parents;
3209
3210        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3211        if (parents == EMPTY_PARENT_LIST)
3212                return NULL;
3213        return parents;
3214}
3215
3216enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
3217{
3218        enum commit_action action = get_commit_action(revs, commit);
3219
3220        if (action == commit_show &&
3221            revs->prune && revs->dense && want_ancestry(revs)) {
3222                /*
3223                 * --full-diff on simplified parents is no good: it
3224                 * will show spurious changes from the commits that
3225                 * were elided.  So we save the parents on the side
3226                 * when --full-diff is in effect.
3227                 */
3228                if (revs->full_diff)
3229                        save_parents(revs, commit);
3230                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3231                        return commit_error;
3232        }
3233        return action;
3234}
3235
3236static void track_linear(struct rev_info *revs, struct commit *commit)
3237{
3238        if (revs->track_first_time) {
3239                revs->linear = 1;
3240                revs->track_first_time = 0;
3241        } else {
3242                struct commit_list *p;
3243                for (p = revs->previous_parents; p; p = p->next)
3244                        if (p->item == NULL || /* first commit */
3245                            !oidcmp(&p->item->object.oid, &commit->object.oid))
3246                                break;
3247                revs->linear = p != NULL;
3248        }
3249        if (revs->reverse) {
3250                if (revs->linear)
3251                        commit->object.flags |= TRACK_LINEAR;
3252        }
3253        free_commit_list(revs->previous_parents);
3254        revs->previous_parents = copy_commit_list(commit->parents);
3255}
3256
3257static struct commit *get_revision_1(struct rev_info *revs)
3258{
3259        while (1) {
3260                struct commit *commit;
3261
3262                if (revs->reflog_info)
3263                        commit = next_reflog_entry(revs->reflog_info);
3264                else
3265                        commit = pop_commit(&revs->commits);
3266
3267                if (!commit)
3268                        return NULL;
3269
3270                if (revs->reflog_info)
3271                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3272
3273                /*
3274                 * If we haven't done the list limiting, we need to look at
3275                 * the parents here. We also need to do the date-based limiting
3276                 * that we'd otherwise have done in limit_list().
3277                 */
3278                if (!revs->limited) {
3279                        if (revs->max_age != -1 &&
3280                            comparison_date(revs, commit) < revs->max_age)
3281                                continue;
3282
3283                        if (revs->reflog_info)
3284                                try_to_simplify_commit(revs, commit);
3285                        else if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3286                                if (!revs->ignore_missing_links)
3287                                        die("Failed to traverse parents of commit %s",
3288                                                oid_to_hex(&commit->object.oid));
3289                        }
3290                }
3291
3292                switch (simplify_commit(revs, commit)) {
3293                case commit_ignore:
3294                        continue;
3295                case commit_error:
3296                        die("Failed to simplify parents of commit %s",
3297                            oid_to_hex(&commit->object.oid));
3298                default:
3299                        if (revs->track_linear)
3300                                track_linear(revs, commit);
3301                        return commit;
3302                }
3303        }
3304}
3305
3306/*
3307 * Return true for entries that have not yet been shown.  (This is an
3308 * object_array_each_func_t.)
3309 */
3310static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3311{
3312        return !(entry->item->flags & SHOWN);
3313}
3314
3315/*
3316 * If array is on the verge of a realloc, garbage-collect any entries
3317 * that have already been shown to try to free up some space.
3318 */
3319static void gc_boundary(struct object_array *array)
3320{
3321        if (array->nr == array->alloc)
3322                object_array_filter(array, entry_unshown, NULL);
3323}
3324
3325static void create_boundary_commit_list(struct rev_info *revs)
3326{
3327        unsigned i;
3328        struct commit *c;
3329        struct object_array *array = &revs->boundary_commits;
3330        struct object_array_entry *objects = array->objects;
3331
3332        /*
3333         * If revs->commits is non-NULL at this point, an error occurred in
3334         * get_revision_1().  Ignore the error and continue printing the
3335         * boundary commits anyway.  (This is what the code has always
3336         * done.)
3337         */
3338        if (revs->commits) {
3339                free_commit_list(revs->commits);
3340                revs->commits = NULL;
3341        }
3342
3343        /*
3344         * Put all of the actual boundary commits from revs->boundary_commits
3345         * into revs->commits
3346         */
3347        for (i = 0; i < array->nr; i++) {
3348                c = (struct commit *)(objects[i].item);
3349                if (!c)
3350                        continue;
3351                if (!(c->object.flags & CHILD_SHOWN))
3352                        continue;
3353                if (c->object.flags & (SHOWN | BOUNDARY))
3354                        continue;
3355                c->object.flags |= BOUNDARY;
3356                commit_list_insert(c, &revs->commits);
3357        }
3358
3359        /*
3360         * If revs->topo_order is set, sort the boundary commits
3361         * in topological order
3362         */
3363        sort_in_topological_order(&revs->commits, revs->sort_order);
3364}
3365
3366static struct commit *get_revision_internal(struct rev_info *revs)
3367{
3368        struct commit *c = NULL;
3369        struct commit_list *l;
3370
3371        if (revs->boundary == 2) {
3372                /*
3373                 * All of the normal commits have already been returned,
3374                 * and we are now returning boundary commits.
3375                 * create_boundary_commit_list() has populated
3376                 * revs->commits with the remaining commits to return.
3377                 */
3378                c = pop_commit(&revs->commits);
3379                if (c)
3380                        c->object.flags |= SHOWN;
3381                return c;
3382        }
3383
3384        /*
3385         * If our max_count counter has reached zero, then we are done. We
3386         * don't simply return NULL because we still might need to show
3387         * boundary commits. But we want to avoid calling get_revision_1, which
3388         * might do a considerable amount of work finding the next commit only
3389         * for us to throw it away.
3390         *
3391         * If it is non-zero, then either we don't have a max_count at all
3392         * (-1), or it is still counting, in which case we decrement.
3393         */
3394        if (revs->max_count) {
3395                c = get_revision_1(revs);
3396                if (c) {
3397                        while (revs->skip_count > 0) {
3398                                revs->skip_count--;
3399                                c = get_revision_1(revs);
3400                                if (!c)
3401                                        break;
3402                        }
3403                }
3404
3405                if (revs->max_count > 0)
3406                        revs->max_count--;
3407        }
3408
3409        if (c)
3410                c->object.flags |= SHOWN;
3411
3412        if (!revs->boundary)
3413                return c;
3414
3415        if (!c) {
3416                /*
3417                 * get_revision_1() runs out the commits, and
3418                 * we are done computing the boundaries.
3419                 * switch to boundary commits output mode.
3420                 */
3421                revs->boundary = 2;
3422
3423                /*
3424                 * Update revs->commits to contain the list of
3425                 * boundary commits.
3426                 */
3427                create_boundary_commit_list(revs);
3428
3429                return get_revision_internal(revs);
3430        }
3431
3432        /*
3433         * boundary commits are the commits that are parents of the
3434         * ones we got from get_revision_1() but they themselves are
3435         * not returned from get_revision_1().  Before returning
3436         * 'c', we need to mark its parents that they could be boundaries.
3437         */
3438
3439        for (l = c->parents; l; l = l->next) {
3440                struct object *p;
3441                p = &(l->item->object);
3442                if (p->flags & (CHILD_SHOWN | SHOWN))
3443                        continue;
3444                p->flags |= CHILD_SHOWN;
3445                gc_boundary(&revs->boundary_commits);
3446                add_object_array(p, NULL, &revs->boundary_commits);
3447        }
3448
3449        return c;
3450}
3451
3452struct commit *get_revision(struct rev_info *revs)
3453{
3454        struct commit *c;
3455        struct commit_list *reversed;
3456
3457        if (revs->reverse) {
3458                reversed = NULL;
3459                while ((c = get_revision_internal(revs)))
3460                        commit_list_insert(c, &reversed);
3461                revs->commits = reversed;
3462                revs->reverse = 0;
3463                revs->reverse_output_stage = 1;
3464        }
3465
3466        if (revs->reverse_output_stage) {
3467                c = pop_commit(&revs->commits);
3468                if (revs->track_linear)
3469                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3470                return c;
3471        }
3472
3473        c = get_revision_internal(revs);
3474        if (c && revs->graph)
3475                graph_update(revs->graph, c);
3476        if (!c) {
3477                free_saved_parents(revs);
3478                if (revs->previous_parents) {
3479                        free_commit_list(revs->previous_parents);
3480                        revs->previous_parents = NULL;
3481                }
3482        }
3483        return c;
3484}
3485
3486char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3487{
3488        if (commit->object.flags & BOUNDARY)
3489                return "-";
3490        else if (commit->object.flags & UNINTERESTING)
3491                return "^";
3492        else if (commit->object.flags & PATCHSAME)
3493                return "=";
3494        else if (!revs || revs->left_right) {
3495                if (commit->object.flags & SYMMETRIC_LEFT)
3496                        return "<";
3497                else
3498                        return ">";
3499        } else if (revs->graph)
3500                return "*";
3501        else if (revs->cherry_mark)
3502                return "+";
3503        return "";
3504}
3505
3506void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3507{
3508        char *mark = get_revision_mark(revs, commit);
3509        if (!strlen(mark))
3510                return;
3511        fputs(mark, stdout);
3512        putchar(' ');
3513}