revision.con commit Merge branch 'bp/fsmonitor' (e05336b)
   1#include "cache.h"
   2#include "tag.h"
   3#include "blob.h"
   4#include "tree.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "refs.h"
   8#include "revision.h"
   9#include "graph.h"
  10#include "grep.h"
  11#include "reflog-walk.h"
  12#include "patch-ids.h"
  13#include "decorate.h"
  14#include "log-tree.h"
  15#include "string-list.h"
  16#include "line-log.h"
  17#include "mailmap.h"
  18#include "commit-slab.h"
  19#include "dir.h"
  20#include "cache-tree.h"
  21#include "bisect.h"
  22#include "packfile.h"
  23#include "worktree.h"
  24#include "argv-array.h"
  25
  26volatile show_early_output_fn_t show_early_output;
  27
  28static const char *term_bad;
  29static const char *term_good;
  30
  31void show_object_with_name(FILE *out, struct object *obj, const char *name)
  32{
  33        const char *p;
  34
  35        fprintf(out, "%s ", oid_to_hex(&obj->oid));
  36        for (p = name; *p && *p != '\n'; p++)
  37                fputc(*p, out);
  38        fputc('\n', out);
  39}
  40
  41static void mark_blob_uninteresting(struct blob *blob)
  42{
  43        if (!blob)
  44                return;
  45        if (blob->object.flags & UNINTERESTING)
  46                return;
  47        blob->object.flags |= UNINTERESTING;
  48}
  49
  50static void mark_tree_contents_uninteresting(struct tree *tree)
  51{
  52        struct tree_desc desc;
  53        struct name_entry entry;
  54        struct object *obj = &tree->object;
  55
  56        if (!has_object_file(&obj->oid))
  57                return;
  58        if (parse_tree(tree) < 0)
  59                die("bad tree %s", oid_to_hex(&obj->oid));
  60
  61        init_tree_desc(&desc, tree->buffer, tree->size);
  62        while (tree_entry(&desc, &entry)) {
  63                switch (object_type(entry.mode)) {
  64                case OBJ_TREE:
  65                        mark_tree_uninteresting(lookup_tree(entry.oid));
  66                        break;
  67                case OBJ_BLOB:
  68                        mark_blob_uninteresting(lookup_blob(entry.oid));
  69                        break;
  70                default:
  71                        /* Subproject commit - not in this repository */
  72                        break;
  73                }
  74        }
  75
  76        /*
  77         * We don't care about the tree any more
  78         * after it has been marked uninteresting.
  79         */
  80        free_tree_buffer(tree);
  81}
  82
  83void mark_tree_uninteresting(struct tree *tree)
  84{
  85        struct object *obj;
  86
  87        if (!tree)
  88                return;
  89
  90        obj = &tree->object;
  91        if (obj->flags & UNINTERESTING)
  92                return;
  93        obj->flags |= UNINTERESTING;
  94        mark_tree_contents_uninteresting(tree);
  95}
  96
  97void mark_parents_uninteresting(struct commit *commit)
  98{
  99        struct commit_list *parents = NULL, *l;
 100
 101        for (l = commit->parents; l; l = l->next)
 102                commit_list_insert(l->item, &parents);
 103
 104        while (parents) {
 105                struct commit *commit = pop_commit(&parents);
 106
 107                while (commit) {
 108                        /*
 109                         * A missing commit is ok iff its parent is marked
 110                         * uninteresting.
 111                         *
 112                         * We just mark such a thing parsed, so that when
 113                         * it is popped next time around, we won't be trying
 114                         * to parse it and get an error.
 115                         */
 116                        if (!has_object_file(&commit->object.oid))
 117                                commit->object.parsed = 1;
 118
 119                        if (commit->object.flags & UNINTERESTING)
 120                                break;
 121
 122                        commit->object.flags |= UNINTERESTING;
 123
 124                        /*
 125                         * Normally we haven't parsed the parent
 126                         * yet, so we won't have a parent of a parent
 127                         * here. However, it may turn out that we've
 128                         * reached this commit some other way (where it
 129                         * wasn't uninteresting), in which case we need
 130                         * to mark its parents recursively too..
 131                         */
 132                        if (!commit->parents)
 133                                break;
 134
 135                        for (l = commit->parents->next; l; l = l->next)
 136                                commit_list_insert(l->item, &parents);
 137                        commit = commit->parents->item;
 138                }
 139        }
 140}
 141
 142static void add_pending_object_with_path(struct rev_info *revs,
 143                                         struct object *obj,
 144                                         const char *name, unsigned mode,
 145                                         const char *path)
 146{
 147        if (!obj)
 148                return;
 149        if (revs->no_walk && (obj->flags & UNINTERESTING))
 150                revs->no_walk = 0;
 151        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 152                struct strbuf buf = STRBUF_INIT;
 153                int len = interpret_branch_name(name, 0, &buf, 0);
 154
 155                if (0 < len && name[len] && buf.len)
 156                        strbuf_addstr(&buf, name + len);
 157                add_reflog_for_walk(revs->reflog_info,
 158                                    (struct commit *)obj,
 159                                    buf.buf[0] ? buf.buf: name);
 160                strbuf_release(&buf);
 161                return; /* do not add the commit itself */
 162        }
 163        add_object_array_with_path(obj, name, &revs->pending, mode, path);
 164}
 165
 166static void add_pending_object_with_mode(struct rev_info *revs,
 167                                         struct object *obj,
 168                                         const char *name, unsigned mode)
 169{
 170        add_pending_object_with_path(revs, obj, name, mode, NULL);
 171}
 172
 173void add_pending_object(struct rev_info *revs,
 174                        struct object *obj, const char *name)
 175{
 176        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 177}
 178
 179void add_head_to_pending(struct rev_info *revs)
 180{
 181        struct object_id oid;
 182        struct object *obj;
 183        if (get_oid("HEAD", &oid))
 184                return;
 185        obj = parse_object(&oid);
 186        if (!obj)
 187                return;
 188        add_pending_object(revs, obj, "HEAD");
 189}
 190
 191static struct object *get_reference(struct rev_info *revs, const char *name,
 192                                    const struct object_id *oid,
 193                                    unsigned int flags)
 194{
 195        struct object *object;
 196
 197        object = parse_object(oid);
 198        if (!object) {
 199                if (revs->ignore_missing)
 200                        return object;
 201                die("bad object %s", name);
 202        }
 203        object->flags |= flags;
 204        return object;
 205}
 206
 207void add_pending_oid(struct rev_info *revs, const char *name,
 208                      const struct object_id *oid, unsigned int flags)
 209{
 210        struct object *object = get_reference(revs, name, oid, flags);
 211        add_pending_object(revs, object, name);
 212}
 213
 214static struct commit *handle_commit(struct rev_info *revs,
 215                                    struct object_array_entry *entry)
 216{
 217        struct object *object = entry->item;
 218        const char *name = entry->name;
 219        const char *path = entry->path;
 220        unsigned int mode = entry->mode;
 221        unsigned long flags = object->flags;
 222
 223        /*
 224         * Tag object? Look what it points to..
 225         */
 226        while (object->type == OBJ_TAG) {
 227                struct tag *tag = (struct tag *) object;
 228                if (revs->tag_objects && !(flags & UNINTERESTING))
 229                        add_pending_object(revs, object, tag->tag);
 230                if (!tag->tagged)
 231                        die("bad tag");
 232                object = parse_object(&tag->tagged->oid);
 233                if (!object) {
 234                        if (revs->ignore_missing_links || (flags & UNINTERESTING))
 235                                return NULL;
 236                        die("bad object %s", oid_to_hex(&tag->tagged->oid));
 237                }
 238                object->flags |= flags;
 239                /*
 240                 * We'll handle the tagged object by looping or dropping
 241                 * through to the non-tag handlers below. Do not
 242                 * propagate path data from the tag's pending entry.
 243                 */
 244                path = NULL;
 245                mode = 0;
 246        }
 247
 248        /*
 249         * Commit object? Just return it, we'll do all the complex
 250         * reachability crud.
 251         */
 252        if (object->type == OBJ_COMMIT) {
 253                struct commit *commit = (struct commit *)object;
 254                if (parse_commit(commit) < 0)
 255                        die("unable to parse commit %s", name);
 256                if (flags & UNINTERESTING) {
 257                        mark_parents_uninteresting(commit);
 258                        revs->limited = 1;
 259                }
 260                if (revs->show_source && !commit->util)
 261                        commit->util = xstrdup(name);
 262                return commit;
 263        }
 264
 265        /*
 266         * Tree object? Either mark it uninteresting, or add it
 267         * to the list of objects to look at later..
 268         */
 269        if (object->type == OBJ_TREE) {
 270                struct tree *tree = (struct tree *)object;
 271                if (!revs->tree_objects)
 272                        return NULL;
 273                if (flags & UNINTERESTING) {
 274                        mark_tree_contents_uninteresting(tree);
 275                        return NULL;
 276                }
 277                add_pending_object_with_path(revs, object, name, mode, path);
 278                return NULL;
 279        }
 280
 281        /*
 282         * Blob object? You know the drill by now..
 283         */
 284        if (object->type == OBJ_BLOB) {
 285                if (!revs->blob_objects)
 286                        return NULL;
 287                if (flags & UNINTERESTING)
 288                        return NULL;
 289                add_pending_object_with_path(revs, object, name, mode, path);
 290                return NULL;
 291        }
 292        die("%s is unknown object", name);
 293}
 294
 295static int everybody_uninteresting(struct commit_list *orig,
 296                                   struct commit **interesting_cache)
 297{
 298        struct commit_list *list = orig;
 299
 300        if (*interesting_cache) {
 301                struct commit *commit = *interesting_cache;
 302                if (!(commit->object.flags & UNINTERESTING))
 303                        return 0;
 304        }
 305
 306        while (list) {
 307                struct commit *commit = list->item;
 308                list = list->next;
 309                if (commit->object.flags & UNINTERESTING)
 310                        continue;
 311
 312                *interesting_cache = commit;
 313                return 0;
 314        }
 315        return 1;
 316}
 317
 318/*
 319 * A definition of "relevant" commit that we can use to simplify limited graphs
 320 * by eliminating side branches.
 321 *
 322 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 323 * in our list), or that is a specified BOTTOM commit. Then after computing
 324 * a limited list, during processing we can generally ignore boundary merges
 325 * coming from outside the graph, (ie from irrelevant parents), and treat
 326 * those merges as if they were single-parent. TREESAME is defined to consider
 327 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 328 * we don't care if we were !TREESAME to non-graph parents.
 329 *
 330 * Treating bottom commits as relevant ensures that a limited graph's
 331 * connection to the actual bottom commit is not viewed as a side branch, but
 332 * treated as part of the graph. For example:
 333 *
 334 *   ....Z...A---X---o---o---B
 335 *        .     /
 336 *         W---Y
 337 *
 338 * When computing "A..B", the A-X connection is at least as important as
 339 * Y-X, despite A being flagged UNINTERESTING.
 340 *
 341 * And when computing --ancestry-path "A..B", the A-X connection is more
 342 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 343 */
 344static inline int relevant_commit(struct commit *commit)
 345{
 346        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 347}
 348
 349/*
 350 * Return a single relevant commit from a parent list. If we are a TREESAME
 351 * commit, and this selects one of our parents, then we can safely simplify to
 352 * that parent.
 353 */
 354static struct commit *one_relevant_parent(const struct rev_info *revs,
 355                                          struct commit_list *orig)
 356{
 357        struct commit_list *list = orig;
 358        struct commit *relevant = NULL;
 359
 360        if (!orig)
 361                return NULL;
 362
 363        /*
 364         * For 1-parent commits, or if first-parent-only, then return that
 365         * first parent (even if not "relevant" by the above definition).
 366         * TREESAME will have been set purely on that parent.
 367         */
 368        if (revs->first_parent_only || !orig->next)
 369                return orig->item;
 370
 371        /*
 372         * For multi-parent commits, identify a sole relevant parent, if any.
 373         * If we have only one relevant parent, then TREESAME will be set purely
 374         * with regard to that parent, and we can simplify accordingly.
 375         *
 376         * If we have more than one relevant parent, or no relevant parents
 377         * (and multiple irrelevant ones), then we can't select a parent here
 378         * and return NULL.
 379         */
 380        while (list) {
 381                struct commit *commit = list->item;
 382                list = list->next;
 383                if (relevant_commit(commit)) {
 384                        if (relevant)
 385                                return NULL;
 386                        relevant = commit;
 387                }
 388        }
 389        return relevant;
 390}
 391
 392/*
 393 * The goal is to get REV_TREE_NEW as the result only if the
 394 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 395 * if the whole diff is removal of old data, and otherwise
 396 * REV_TREE_DIFFERENT (of course if the trees are the same we
 397 * want REV_TREE_SAME).
 398 *
 399 * The only time we care about the distinction is when
 400 * remove_empty_trees is in effect, in which case we care only about
 401 * whether the whole change is REV_TREE_NEW, or if there's another type
 402 * of change. Which means we can stop the diff early in either of these
 403 * cases:
 404 *
 405 *   1. We're not using remove_empty_trees at all.
 406 *
 407 *   2. We saw anything except REV_TREE_NEW.
 408 */
 409static int tree_difference = REV_TREE_SAME;
 410
 411static void file_add_remove(struct diff_options *options,
 412                    int addremove, unsigned mode,
 413                    const struct object_id *oid,
 414                    int oid_valid,
 415                    const char *fullpath, unsigned dirty_submodule)
 416{
 417        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 418        struct rev_info *revs = options->change_fn_data;
 419
 420        tree_difference |= diff;
 421        if (!revs->remove_empty_trees || tree_difference != REV_TREE_NEW)
 422                options->flags.has_changes = 1;
 423}
 424
 425static void file_change(struct diff_options *options,
 426                 unsigned old_mode, unsigned new_mode,
 427                 const struct object_id *old_oid,
 428                 const struct object_id *new_oid,
 429                 int old_oid_valid, int new_oid_valid,
 430                 const char *fullpath,
 431                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 432{
 433        tree_difference = REV_TREE_DIFFERENT;
 434        options->flags.has_changes = 1;
 435}
 436
 437static int rev_compare_tree(struct rev_info *revs,
 438                            struct commit *parent, struct commit *commit)
 439{
 440        struct tree *t1 = parent->tree;
 441        struct tree *t2 = commit->tree;
 442
 443        if (!t1)
 444                return REV_TREE_NEW;
 445        if (!t2)
 446                return REV_TREE_OLD;
 447
 448        if (revs->simplify_by_decoration) {
 449                /*
 450                 * If we are simplifying by decoration, then the commit
 451                 * is worth showing if it has a tag pointing at it.
 452                 */
 453                if (get_name_decoration(&commit->object))
 454                        return REV_TREE_DIFFERENT;
 455                /*
 456                 * A commit that is not pointed by a tag is uninteresting
 457                 * if we are not limited by path.  This means that you will
 458                 * see the usual "commits that touch the paths" plus any
 459                 * tagged commit by specifying both --simplify-by-decoration
 460                 * and pathspec.
 461                 */
 462                if (!revs->prune_data.nr)
 463                        return REV_TREE_SAME;
 464        }
 465
 466        tree_difference = REV_TREE_SAME;
 467        revs->pruning.flags.has_changes = 0;
 468        if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
 469                           &revs->pruning) < 0)
 470                return REV_TREE_DIFFERENT;
 471        return tree_difference;
 472}
 473
 474static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 475{
 476        int retval;
 477        struct tree *t1 = commit->tree;
 478
 479        if (!t1)
 480                return 0;
 481
 482        tree_difference = REV_TREE_SAME;
 483        revs->pruning.flags.has_changes = 0;
 484        retval = diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);
 485
 486        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 487}
 488
 489struct treesame_state {
 490        unsigned int nparents;
 491        unsigned char treesame[FLEX_ARRAY];
 492};
 493
 494static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 495{
 496        unsigned n = commit_list_count(commit->parents);
 497        struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 498        st->nparents = n;
 499        add_decoration(&revs->treesame, &commit->object, st);
 500        return st;
 501}
 502
 503/*
 504 * Must be called immediately after removing the nth_parent from a commit's
 505 * parent list, if we are maintaining the per-parent treesame[] decoration.
 506 * This does not recalculate the master TREESAME flag - update_treesame()
 507 * should be called to update it after a sequence of treesame[] modifications
 508 * that may have affected it.
 509 */
 510static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 511{
 512        struct treesame_state *st;
 513        int old_same;
 514
 515        if (!commit->parents) {
 516                /*
 517                 * Have just removed the only parent from a non-merge.
 518                 * Different handling, as we lack decoration.
 519                 */
 520                if (nth_parent != 0)
 521                        die("compact_treesame %u", nth_parent);
 522                old_same = !!(commit->object.flags & TREESAME);
 523                if (rev_same_tree_as_empty(revs, commit))
 524                        commit->object.flags |= TREESAME;
 525                else
 526                        commit->object.flags &= ~TREESAME;
 527                return old_same;
 528        }
 529
 530        st = lookup_decoration(&revs->treesame, &commit->object);
 531        if (!st || nth_parent >= st->nparents)
 532                die("compact_treesame %u", nth_parent);
 533
 534        old_same = st->treesame[nth_parent];
 535        memmove(st->treesame + nth_parent,
 536                st->treesame + nth_parent + 1,
 537                st->nparents - nth_parent - 1);
 538
 539        /*
 540         * If we've just become a non-merge commit, update TREESAME
 541         * immediately, and remove the no-longer-needed decoration.
 542         * If still a merge, defer update until update_treesame().
 543         */
 544        if (--st->nparents == 1) {
 545                if (commit->parents->next)
 546                        die("compact_treesame parents mismatch");
 547                if (st->treesame[0] && revs->dense)
 548                        commit->object.flags |= TREESAME;
 549                else
 550                        commit->object.flags &= ~TREESAME;
 551                free(add_decoration(&revs->treesame, &commit->object, NULL));
 552        }
 553
 554        return old_same;
 555}
 556
 557static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 558{
 559        if (commit->parents && commit->parents->next) {
 560                unsigned n;
 561                struct treesame_state *st;
 562                struct commit_list *p;
 563                unsigned relevant_parents;
 564                unsigned relevant_change, irrelevant_change;
 565
 566                st = lookup_decoration(&revs->treesame, &commit->object);
 567                if (!st)
 568                        die("update_treesame %s", oid_to_hex(&commit->object.oid));
 569                relevant_parents = 0;
 570                relevant_change = irrelevant_change = 0;
 571                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 572                        if (relevant_commit(p->item)) {
 573                                relevant_change |= !st->treesame[n];
 574                                relevant_parents++;
 575                        } else
 576                                irrelevant_change |= !st->treesame[n];
 577                }
 578                if (relevant_parents ? relevant_change : irrelevant_change)
 579                        commit->object.flags &= ~TREESAME;
 580                else
 581                        commit->object.flags |= TREESAME;
 582        }
 583
 584        return commit->object.flags & TREESAME;
 585}
 586
 587static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 588{
 589        /*
 590         * TREESAME is irrelevant unless prune && dense;
 591         * if simplify_history is set, we can't have a mixture of TREESAME and
 592         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 593         *    decoration anyway);
 594         * if first_parent_only is set, then the TREESAME flag is locked
 595         *    against the first parent (and again we lack treesame[] decoration).
 596         */
 597        return revs->prune && revs->dense &&
 598               !revs->simplify_history &&
 599               !revs->first_parent_only;
 600}
 601
 602static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 603{
 604        struct commit_list **pp, *parent;
 605        struct treesame_state *ts = NULL;
 606        int relevant_change = 0, irrelevant_change = 0;
 607        int relevant_parents, nth_parent;
 608
 609        /*
 610         * If we don't do pruning, everything is interesting
 611         */
 612        if (!revs->prune)
 613                return;
 614
 615        if (!commit->tree)
 616                return;
 617
 618        if (!commit->parents) {
 619                if (rev_same_tree_as_empty(revs, commit))
 620                        commit->object.flags |= TREESAME;
 621                return;
 622        }
 623
 624        /*
 625         * Normal non-merge commit? If we don't want to make the
 626         * history dense, we consider it always to be a change..
 627         */
 628        if (!revs->dense && !commit->parents->next)
 629                return;
 630
 631        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 632             (parent = *pp) != NULL;
 633             pp = &parent->next, nth_parent++) {
 634                struct commit *p = parent->item;
 635                if (relevant_commit(p))
 636                        relevant_parents++;
 637
 638                if (nth_parent == 1) {
 639                        /*
 640                         * This our second loop iteration - so we now know
 641                         * we're dealing with a merge.
 642                         *
 643                         * Do not compare with later parents when we care only about
 644                         * the first parent chain, in order to avoid derailing the
 645                         * traversal to follow a side branch that brought everything
 646                         * in the path we are limited to by the pathspec.
 647                         */
 648                        if (revs->first_parent_only)
 649                                break;
 650                        /*
 651                         * If this will remain a potentially-simplifiable
 652                         * merge, remember per-parent treesame if needed.
 653                         * Initialise the array with the comparison from our
 654                         * first iteration.
 655                         */
 656                        if (revs->treesame.name &&
 657                            !revs->simplify_history &&
 658                            !(commit->object.flags & UNINTERESTING)) {
 659                                ts = initialise_treesame(revs, commit);
 660                                if (!(irrelevant_change || relevant_change))
 661                                        ts->treesame[0] = 1;
 662                        }
 663                }
 664                if (parse_commit(p) < 0)
 665                        die("cannot simplify commit %s (because of %s)",
 666                            oid_to_hex(&commit->object.oid),
 667                            oid_to_hex(&p->object.oid));
 668                switch (rev_compare_tree(revs, p, commit)) {
 669                case REV_TREE_SAME:
 670                        if (!revs->simplify_history || !relevant_commit(p)) {
 671                                /* Even if a merge with an uninteresting
 672                                 * side branch brought the entire change
 673                                 * we are interested in, we do not want
 674                                 * to lose the other branches of this
 675                                 * merge, so we just keep going.
 676                                 */
 677                                if (ts)
 678                                        ts->treesame[nth_parent] = 1;
 679                                continue;
 680                        }
 681                        parent->next = NULL;
 682                        commit->parents = parent;
 683                        commit->object.flags |= TREESAME;
 684                        return;
 685
 686                case REV_TREE_NEW:
 687                        if (revs->remove_empty_trees &&
 688                            rev_same_tree_as_empty(revs, p)) {
 689                                /* We are adding all the specified
 690                                 * paths from this parent, so the
 691                                 * history beyond this parent is not
 692                                 * interesting.  Remove its parents
 693                                 * (they are grandparents for us).
 694                                 * IOW, we pretend this parent is a
 695                                 * "root" commit.
 696                                 */
 697                                if (parse_commit(p) < 0)
 698                                        die("cannot simplify commit %s (invalid %s)",
 699                                            oid_to_hex(&commit->object.oid),
 700                                            oid_to_hex(&p->object.oid));
 701                                p->parents = NULL;
 702                        }
 703                /* fallthrough */
 704                case REV_TREE_OLD:
 705                case REV_TREE_DIFFERENT:
 706                        if (relevant_commit(p))
 707                                relevant_change = 1;
 708                        else
 709                                irrelevant_change = 1;
 710                        continue;
 711                }
 712                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
 713        }
 714
 715        /*
 716         * TREESAME is straightforward for single-parent commits. For merge
 717         * commits, it is most useful to define it so that "irrelevant"
 718         * parents cannot make us !TREESAME - if we have any relevant
 719         * parents, then we only consider TREESAMEness with respect to them,
 720         * allowing irrelevant merges from uninteresting branches to be
 721         * simplified away. Only if we have only irrelevant parents do we
 722         * base TREESAME on them. Note that this logic is replicated in
 723         * update_treesame, which should be kept in sync.
 724         */
 725        if (relevant_parents ? !relevant_change : !irrelevant_change)
 726                commit->object.flags |= TREESAME;
 727}
 728
 729static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 730                    struct commit_list *cached_base, struct commit_list **cache)
 731{
 732        struct commit_list *new_entry;
 733
 734        if (cached_base && p->date < cached_base->item->date)
 735                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 736        else
 737                new_entry = commit_list_insert_by_date(p, head);
 738
 739        if (cache && (!*cache || p->date < (*cache)->item->date))
 740                *cache = new_entry;
 741}
 742
 743static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 744                    struct commit_list **list, struct commit_list **cache_ptr)
 745{
 746        struct commit_list *parent = commit->parents;
 747        unsigned left_flag;
 748        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 749
 750        if (commit->object.flags & ADDED)
 751                return 0;
 752        commit->object.flags |= ADDED;
 753
 754        if (revs->include_check &&
 755            !revs->include_check(commit, revs->include_check_data))
 756                return 0;
 757
 758        /*
 759         * If the commit is uninteresting, don't try to
 760         * prune parents - we want the maximal uninteresting
 761         * set.
 762         *
 763         * Normally we haven't parsed the parent
 764         * yet, so we won't have a parent of a parent
 765         * here. However, it may turn out that we've
 766         * reached this commit some other way (where it
 767         * wasn't uninteresting), in which case we need
 768         * to mark its parents recursively too..
 769         */
 770        if (commit->object.flags & UNINTERESTING) {
 771                while (parent) {
 772                        struct commit *p = parent->item;
 773                        parent = parent->next;
 774                        if (p)
 775                                p->object.flags |= UNINTERESTING;
 776                        if (parse_commit_gently(p, 1) < 0)
 777                                continue;
 778                        if (p->parents)
 779                                mark_parents_uninteresting(p);
 780                        if (p->object.flags & SEEN)
 781                                continue;
 782                        p->object.flags |= SEEN;
 783                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 784                }
 785                return 0;
 786        }
 787
 788        /*
 789         * Ok, the commit wasn't uninteresting. Try to
 790         * simplify the commit history and find the parent
 791         * that has no differences in the path set if one exists.
 792         */
 793        try_to_simplify_commit(revs, commit);
 794
 795        if (revs->no_walk)
 796                return 0;
 797
 798        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 799
 800        for (parent = commit->parents; parent; parent = parent->next) {
 801                struct commit *p = parent->item;
 802
 803                if (parse_commit_gently(p, revs->ignore_missing_links) < 0)
 804                        return -1;
 805                if (revs->show_source && !p->util)
 806                        p->util = commit->util;
 807                p->object.flags |= left_flag;
 808                if (!(p->object.flags & SEEN)) {
 809                        p->object.flags |= SEEN;
 810                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 811                }
 812                if (revs->first_parent_only)
 813                        break;
 814        }
 815        return 0;
 816}
 817
 818static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 819{
 820        struct commit_list *p;
 821        int left_count = 0, right_count = 0;
 822        int left_first;
 823        struct patch_ids ids;
 824        unsigned cherry_flag;
 825
 826        /* First count the commits on the left and on the right */
 827        for (p = list; p; p = p->next) {
 828                struct commit *commit = p->item;
 829                unsigned flags = commit->object.flags;
 830                if (flags & BOUNDARY)
 831                        ;
 832                else if (flags & SYMMETRIC_LEFT)
 833                        left_count++;
 834                else
 835                        right_count++;
 836        }
 837
 838        if (!left_count || !right_count)
 839                return;
 840
 841        left_first = left_count < right_count;
 842        init_patch_ids(&ids);
 843        ids.diffopts.pathspec = revs->diffopt.pathspec;
 844
 845        /* Compute patch-ids for one side */
 846        for (p = list; p; p = p->next) {
 847                struct commit *commit = p->item;
 848                unsigned flags = commit->object.flags;
 849
 850                if (flags & BOUNDARY)
 851                        continue;
 852                /*
 853                 * If we have fewer left, left_first is set and we omit
 854                 * commits on the right branch in this loop.  If we have
 855                 * fewer right, we skip the left ones.
 856                 */
 857                if (left_first != !!(flags & SYMMETRIC_LEFT))
 858                        continue;
 859                add_commit_patch_id(commit, &ids);
 860        }
 861
 862        /* either cherry_mark or cherry_pick are true */
 863        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 864
 865        /* Check the other side */
 866        for (p = list; p; p = p->next) {
 867                struct commit *commit = p->item;
 868                struct patch_id *id;
 869                unsigned flags = commit->object.flags;
 870
 871                if (flags & BOUNDARY)
 872                        continue;
 873                /*
 874                 * If we have fewer left, left_first is set and we omit
 875                 * commits on the left branch in this loop.
 876                 */
 877                if (left_first == !!(flags & SYMMETRIC_LEFT))
 878                        continue;
 879
 880                /*
 881                 * Have we seen the same patch id?
 882                 */
 883                id = has_commit_patch_id(commit, &ids);
 884                if (!id)
 885                        continue;
 886
 887                commit->object.flags |= cherry_flag;
 888                id->commit->object.flags |= cherry_flag;
 889        }
 890
 891        free_patch_ids(&ids);
 892}
 893
 894/* How many extra uninteresting commits we want to see.. */
 895#define SLOP 5
 896
 897static int still_interesting(struct commit_list *src, timestamp_t date, int slop,
 898                             struct commit **interesting_cache)
 899{
 900        /*
 901         * No source list at all? We're definitely done..
 902         */
 903        if (!src)
 904                return 0;
 905
 906        /*
 907         * Does the destination list contain entries with a date
 908         * before the source list? Definitely _not_ done.
 909         */
 910        if (date <= src->item->date)
 911                return SLOP;
 912
 913        /*
 914         * Does the source list still have interesting commits in
 915         * it? Definitely not done..
 916         */
 917        if (!everybody_uninteresting(src, interesting_cache))
 918                return SLOP;
 919
 920        /* Ok, we're closing in.. */
 921        return slop-1;
 922}
 923
 924/*
 925 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 926 * of B but not ancestors of A but further limits the result to those
 927 * that are descendants of A.  This takes the list of bottom commits and
 928 * the result of "A..B" without --ancestry-path, and limits the latter
 929 * further to the ones that can reach one of the commits in "bottom".
 930 */
 931static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 932{
 933        struct commit_list *p;
 934        struct commit_list *rlist = NULL;
 935        int made_progress;
 936
 937        /*
 938         * Reverse the list so that it will be likely that we would
 939         * process parents before children.
 940         */
 941        for (p = list; p; p = p->next)
 942                commit_list_insert(p->item, &rlist);
 943
 944        for (p = bottom; p; p = p->next)
 945                p->item->object.flags |= TMP_MARK;
 946
 947        /*
 948         * Mark the ones that can reach bottom commits in "list",
 949         * in a bottom-up fashion.
 950         */
 951        do {
 952                made_progress = 0;
 953                for (p = rlist; p; p = p->next) {
 954                        struct commit *c = p->item;
 955                        struct commit_list *parents;
 956                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 957                                continue;
 958                        for (parents = c->parents;
 959                             parents;
 960                             parents = parents->next) {
 961                                if (!(parents->item->object.flags & TMP_MARK))
 962                                        continue;
 963                                c->object.flags |= TMP_MARK;
 964                                made_progress = 1;
 965                                break;
 966                        }
 967                }
 968        } while (made_progress);
 969
 970        /*
 971         * NEEDSWORK: decide if we want to remove parents that are
 972         * not marked with TMP_MARK from commit->parents for commits
 973         * in the resulting list.  We may not want to do that, though.
 974         */
 975
 976        /*
 977         * The ones that are not marked with TMP_MARK are uninteresting
 978         */
 979        for (p = list; p; p = p->next) {
 980                struct commit *c = p->item;
 981                if (c->object.flags & TMP_MARK)
 982                        continue;
 983                c->object.flags |= UNINTERESTING;
 984        }
 985
 986        /* We are done with the TMP_MARK */
 987        for (p = list; p; p = p->next)
 988                p->item->object.flags &= ~TMP_MARK;
 989        for (p = bottom; p; p = p->next)
 990                p->item->object.flags &= ~TMP_MARK;
 991        free_commit_list(rlist);
 992}
 993
 994/*
 995 * Before walking the history, keep the set of "negative" refs the
 996 * caller has asked to exclude.
 997 *
 998 * This is used to compute "rev-list --ancestry-path A..B", as we need
 999 * to filter the result of "A..B" further to the ones that can actually
1000 * reach A.
1001 */
1002static struct commit_list *collect_bottom_commits(struct commit_list *list)
1003{
1004        struct commit_list *elem, *bottom = NULL;
1005        for (elem = list; elem; elem = elem->next)
1006                if (elem->item->object.flags & BOTTOM)
1007                        commit_list_insert(elem->item, &bottom);
1008        return bottom;
1009}
1010
1011/* Assumes either left_only or right_only is set */
1012static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1013{
1014        struct commit_list *p;
1015
1016        for (p = list; p; p = p->next) {
1017                struct commit *commit = p->item;
1018
1019                if (revs->right_only) {
1020                        if (commit->object.flags & SYMMETRIC_LEFT)
1021                                commit->object.flags |= SHOWN;
1022                } else  /* revs->left_only is set */
1023                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1024                                commit->object.flags |= SHOWN;
1025        }
1026}
1027
1028static int limit_list(struct rev_info *revs)
1029{
1030        int slop = SLOP;
1031        timestamp_t date = TIME_MAX;
1032        struct commit_list *list = revs->commits;
1033        struct commit_list *newlist = NULL;
1034        struct commit_list **p = &newlist;
1035        struct commit_list *bottom = NULL;
1036        struct commit *interesting_cache = NULL;
1037
1038        if (revs->ancestry_path) {
1039                bottom = collect_bottom_commits(list);
1040                if (!bottom)
1041                        die("--ancestry-path given but there are no bottom commits");
1042        }
1043
1044        while (list) {
1045                struct commit *commit = pop_commit(&list);
1046                struct object *obj = &commit->object;
1047                show_early_output_fn_t show;
1048
1049                if (commit == interesting_cache)
1050                        interesting_cache = NULL;
1051
1052                if (revs->max_age != -1 && (commit->date < revs->max_age))
1053                        obj->flags |= UNINTERESTING;
1054                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1055                        return -1;
1056                if (obj->flags & UNINTERESTING) {
1057                        mark_parents_uninteresting(commit);
1058                        if (revs->show_all)
1059                                p = &commit_list_insert(commit, p)->next;
1060                        slop = still_interesting(list, date, slop, &interesting_cache);
1061                        if (slop)
1062                                continue;
1063                        /* If showing all, add the whole pending list to the end */
1064                        if (revs->show_all)
1065                                *p = list;
1066                        break;
1067                }
1068                if (revs->min_age != -1 && (commit->date > revs->min_age))
1069                        continue;
1070                date = commit->date;
1071                p = &commit_list_insert(commit, p)->next;
1072
1073                show = show_early_output;
1074                if (!show)
1075                        continue;
1076
1077                show(revs, newlist);
1078                show_early_output = NULL;
1079        }
1080        if (revs->cherry_pick || revs->cherry_mark)
1081                cherry_pick_list(newlist, revs);
1082
1083        if (revs->left_only || revs->right_only)
1084                limit_left_right(newlist, revs);
1085
1086        if (bottom) {
1087                limit_to_ancestry(bottom, newlist);
1088                free_commit_list(bottom);
1089        }
1090
1091        /*
1092         * Check if any commits have become TREESAME by some of their parents
1093         * becoming UNINTERESTING.
1094         */
1095        if (limiting_can_increase_treesame(revs))
1096                for (list = newlist; list; list = list->next) {
1097                        struct commit *c = list->item;
1098                        if (c->object.flags & (UNINTERESTING | TREESAME))
1099                                continue;
1100                        update_treesame(revs, c);
1101                }
1102
1103        revs->commits = newlist;
1104        return 0;
1105}
1106
1107/*
1108 * Add an entry to refs->cmdline with the specified information.
1109 * *name is copied.
1110 */
1111static void add_rev_cmdline(struct rev_info *revs,
1112                            struct object *item,
1113                            const char *name,
1114                            int whence,
1115                            unsigned flags)
1116{
1117        struct rev_cmdline_info *info = &revs->cmdline;
1118        unsigned int nr = info->nr;
1119
1120        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1121        info->rev[nr].item = item;
1122        info->rev[nr].name = xstrdup(name);
1123        info->rev[nr].whence = whence;
1124        info->rev[nr].flags = flags;
1125        info->nr++;
1126}
1127
1128static void add_rev_cmdline_list(struct rev_info *revs,
1129                                 struct commit_list *commit_list,
1130                                 int whence,
1131                                 unsigned flags)
1132{
1133        while (commit_list) {
1134                struct object *object = &commit_list->item->object;
1135                add_rev_cmdline(revs, object, oid_to_hex(&object->oid),
1136                                whence, flags);
1137                commit_list = commit_list->next;
1138        }
1139}
1140
1141struct all_refs_cb {
1142        int all_flags;
1143        int warned_bad_reflog;
1144        struct rev_info *all_revs;
1145        const char *name_for_errormsg;
1146        struct ref_store *refs;
1147};
1148
1149int ref_excluded(struct string_list *ref_excludes, const char *path)
1150{
1151        struct string_list_item *item;
1152
1153        if (!ref_excludes)
1154                return 0;
1155        for_each_string_list_item(item, ref_excludes) {
1156                if (!wildmatch(item->string, path, 0))
1157                        return 1;
1158        }
1159        return 0;
1160}
1161
1162static int handle_one_ref(const char *path, const struct object_id *oid,
1163                          int flag, void *cb_data)
1164{
1165        struct all_refs_cb *cb = cb_data;
1166        struct object *object;
1167
1168        if (ref_excluded(cb->all_revs->ref_excludes, path))
1169            return 0;
1170
1171        object = get_reference(cb->all_revs, path, oid, cb->all_flags);
1172        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1173        add_pending_oid(cb->all_revs, path, oid, cb->all_flags);
1174        return 0;
1175}
1176
1177static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1178        unsigned flags)
1179{
1180        cb->all_revs = revs;
1181        cb->all_flags = flags;
1182        revs->rev_input_given = 1;
1183        cb->refs = NULL;
1184}
1185
1186void clear_ref_exclusion(struct string_list **ref_excludes_p)
1187{
1188        if (*ref_excludes_p) {
1189                string_list_clear(*ref_excludes_p, 0);
1190                free(*ref_excludes_p);
1191        }
1192        *ref_excludes_p = NULL;
1193}
1194
1195void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1196{
1197        if (!*ref_excludes_p) {
1198                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1199                (*ref_excludes_p)->strdup_strings = 1;
1200        }
1201        string_list_append(*ref_excludes_p, exclude);
1202}
1203
1204static void handle_refs(struct ref_store *refs,
1205                        struct rev_info *revs, unsigned flags,
1206                        int (*for_each)(struct ref_store *, each_ref_fn, void *))
1207{
1208        struct all_refs_cb cb;
1209
1210        if (!refs) {
1211                /* this could happen with uninitialized submodules */
1212                return;
1213        }
1214
1215        init_all_refs_cb(&cb, revs, flags);
1216        for_each(refs, handle_one_ref, &cb);
1217}
1218
1219static void handle_one_reflog_commit(struct object_id *oid, void *cb_data)
1220{
1221        struct all_refs_cb *cb = cb_data;
1222        if (!is_null_oid(oid)) {
1223                struct object *o = parse_object(oid);
1224                if (o) {
1225                        o->flags |= cb->all_flags;
1226                        /* ??? CMDLINEFLAGS ??? */
1227                        add_pending_object(cb->all_revs, o, "");
1228                }
1229                else if (!cb->warned_bad_reflog) {
1230                        warning("reflog of '%s' references pruned commits",
1231                                cb->name_for_errormsg);
1232                        cb->warned_bad_reflog = 1;
1233                }
1234        }
1235}
1236
1237static int handle_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
1238                const char *email, timestamp_t timestamp, int tz,
1239                const char *message, void *cb_data)
1240{
1241        handle_one_reflog_commit(ooid, cb_data);
1242        handle_one_reflog_commit(noid, cb_data);
1243        return 0;
1244}
1245
1246static int handle_one_reflog(const char *path, const struct object_id *oid,
1247                             int flag, void *cb_data)
1248{
1249        struct all_refs_cb *cb = cb_data;
1250        cb->warned_bad_reflog = 0;
1251        cb->name_for_errormsg = path;
1252        refs_for_each_reflog_ent(cb->refs, path,
1253                                 handle_one_reflog_ent, cb_data);
1254        return 0;
1255}
1256
1257static void add_other_reflogs_to_pending(struct all_refs_cb *cb)
1258{
1259        struct worktree **worktrees, **p;
1260
1261        worktrees = get_worktrees(0);
1262        for (p = worktrees; *p; p++) {
1263                struct worktree *wt = *p;
1264
1265                if (wt->is_current)
1266                        continue;
1267
1268                cb->refs = get_worktree_ref_store(wt);
1269                refs_for_each_reflog(cb->refs,
1270                                     handle_one_reflog,
1271                                     cb);
1272        }
1273        free_worktrees(worktrees);
1274}
1275
1276void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1277{
1278        struct all_refs_cb cb;
1279
1280        cb.all_revs = revs;
1281        cb.all_flags = flags;
1282        cb.refs = get_main_ref_store();
1283        for_each_reflog(handle_one_reflog, &cb);
1284
1285        if (!revs->single_worktree)
1286                add_other_reflogs_to_pending(&cb);
1287}
1288
1289static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1290                           struct strbuf *path)
1291{
1292        size_t baselen = path->len;
1293        int i;
1294
1295        if (it->entry_count >= 0) {
1296                struct tree *tree = lookup_tree(&it->oid);
1297                add_pending_object_with_path(revs, &tree->object, "",
1298                                             040000, path->buf);
1299        }
1300
1301        for (i = 0; i < it->subtree_nr; i++) {
1302                struct cache_tree_sub *sub = it->down[i];
1303                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1304                add_cache_tree(sub->cache_tree, revs, path);
1305                strbuf_setlen(path, baselen);
1306        }
1307
1308}
1309
1310static void do_add_index_objects_to_pending(struct rev_info *revs,
1311                                            struct index_state *istate)
1312{
1313        int i;
1314
1315        for (i = 0; i < istate->cache_nr; i++) {
1316                struct cache_entry *ce = istate->cache[i];
1317                struct blob *blob;
1318
1319                if (S_ISGITLINK(ce->ce_mode))
1320                        continue;
1321
1322                blob = lookup_blob(&ce->oid);
1323                if (!blob)
1324                        die("unable to add index blob to traversal");
1325                add_pending_object_with_path(revs, &blob->object, "",
1326                                             ce->ce_mode, ce->name);
1327        }
1328
1329        if (istate->cache_tree) {
1330                struct strbuf path = STRBUF_INIT;
1331                add_cache_tree(istate->cache_tree, revs, &path);
1332                strbuf_release(&path);
1333        }
1334}
1335
1336void add_index_objects_to_pending(struct rev_info *revs, unsigned int flags)
1337{
1338        struct worktree **worktrees, **p;
1339
1340        read_cache();
1341        do_add_index_objects_to_pending(revs, &the_index);
1342
1343        if (revs->single_worktree)
1344                return;
1345
1346        worktrees = get_worktrees(0);
1347        for (p = worktrees; *p; p++) {
1348                struct worktree *wt = *p;
1349                struct index_state istate = { NULL };
1350
1351                if (wt->is_current)
1352                        continue; /* current index already taken care of */
1353
1354                if (read_index_from(&istate,
1355                                    worktree_git_path(wt, "index")) > 0)
1356                        do_add_index_objects_to_pending(revs, &istate);
1357                discard_index(&istate);
1358        }
1359        free_worktrees(worktrees);
1360}
1361
1362static int add_parents_only(struct rev_info *revs, const char *arg_, int flags,
1363                            int exclude_parent)
1364{
1365        struct object_id oid;
1366        struct object *it;
1367        struct commit *commit;
1368        struct commit_list *parents;
1369        int parent_number;
1370        const char *arg = arg_;
1371
1372        if (*arg == '^') {
1373                flags ^= UNINTERESTING | BOTTOM;
1374                arg++;
1375        }
1376        if (get_oid_committish(arg, &oid))
1377                return 0;
1378        while (1) {
1379                it = get_reference(revs, arg, &oid, 0);
1380                if (!it && revs->ignore_missing)
1381                        return 0;
1382                if (it->type != OBJ_TAG)
1383                        break;
1384                if (!((struct tag*)it)->tagged)
1385                        return 0;
1386                oidcpy(&oid, &((struct tag*)it)->tagged->oid);
1387        }
1388        if (it->type != OBJ_COMMIT)
1389                return 0;
1390        commit = (struct commit *)it;
1391        if (exclude_parent &&
1392            exclude_parent > commit_list_count(commit->parents))
1393                return 0;
1394        for (parents = commit->parents, parent_number = 1;
1395             parents;
1396             parents = parents->next, parent_number++) {
1397                if (exclude_parent && parent_number != exclude_parent)
1398                        continue;
1399
1400                it = &parents->item->object;
1401                it->flags |= flags;
1402                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1403                add_pending_object(revs, it, arg);
1404        }
1405        return 1;
1406}
1407
1408void init_revisions(struct rev_info *revs, const char *prefix)
1409{
1410        memset(revs, 0, sizeof(*revs));
1411
1412        revs->abbrev = DEFAULT_ABBREV;
1413        revs->ignore_merges = 1;
1414        revs->simplify_history = 1;
1415        revs->pruning.flags.recursive = 1;
1416        revs->pruning.flags.quick = 1;
1417        revs->pruning.add_remove = file_add_remove;
1418        revs->pruning.change = file_change;
1419        revs->pruning.change_fn_data = revs;
1420        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1421        revs->dense = 1;
1422        revs->prefix = prefix;
1423        revs->max_age = -1;
1424        revs->min_age = -1;
1425        revs->skip_count = -1;
1426        revs->max_count = -1;
1427        revs->max_parents = -1;
1428        revs->expand_tabs_in_log = -1;
1429
1430        revs->commit_format = CMIT_FMT_DEFAULT;
1431        revs->expand_tabs_in_log_default = 8;
1432
1433        init_grep_defaults();
1434        grep_init(&revs->grep_filter, prefix);
1435        revs->grep_filter.status_only = 1;
1436
1437        diff_setup(&revs->diffopt);
1438        if (prefix && !revs->diffopt.prefix) {
1439                revs->diffopt.prefix = prefix;
1440                revs->diffopt.prefix_length = strlen(prefix);
1441        }
1442
1443        revs->notes_opt.use_default_notes = -1;
1444}
1445
1446static void add_pending_commit_list(struct rev_info *revs,
1447                                    struct commit_list *commit_list,
1448                                    unsigned int flags)
1449{
1450        while (commit_list) {
1451                struct object *object = &commit_list->item->object;
1452                object->flags |= flags;
1453                add_pending_object(revs, object, oid_to_hex(&object->oid));
1454                commit_list = commit_list->next;
1455        }
1456}
1457
1458static void prepare_show_merge(struct rev_info *revs)
1459{
1460        struct commit_list *bases;
1461        struct commit *head, *other;
1462        struct object_id oid;
1463        const char **prune = NULL;
1464        int i, prune_num = 1; /* counting terminating NULL */
1465
1466        if (get_oid("HEAD", &oid))
1467                die("--merge without HEAD?");
1468        head = lookup_commit_or_die(&oid, "HEAD");
1469        if (get_oid("MERGE_HEAD", &oid))
1470                die("--merge without MERGE_HEAD?");
1471        other = lookup_commit_or_die(&oid, "MERGE_HEAD");
1472        add_pending_object(revs, &head->object, "HEAD");
1473        add_pending_object(revs, &other->object, "MERGE_HEAD");
1474        bases = get_merge_bases(head, other);
1475        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1476        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1477        free_commit_list(bases);
1478        head->object.flags |= SYMMETRIC_LEFT;
1479
1480        if (!active_nr)
1481                read_cache();
1482        for (i = 0; i < active_nr; i++) {
1483                const struct cache_entry *ce = active_cache[i];
1484                if (!ce_stage(ce))
1485                        continue;
1486                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1487                        prune_num++;
1488                        REALLOC_ARRAY(prune, prune_num);
1489                        prune[prune_num-2] = ce->name;
1490                        prune[prune_num-1] = NULL;
1491                }
1492                while ((i+1 < active_nr) &&
1493                       ce_same_name(ce, active_cache[i+1]))
1494                        i++;
1495        }
1496        clear_pathspec(&revs->prune_data);
1497        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1498                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1499        revs->limited = 1;
1500}
1501
1502static int dotdot_missing(const char *arg, char *dotdot,
1503                          struct rev_info *revs, int symmetric)
1504{
1505        if (revs->ignore_missing)
1506                return 0;
1507        /* de-munge so we report the full argument */
1508        *dotdot = '.';
1509        die(symmetric
1510            ? "Invalid symmetric difference expression %s"
1511            : "Invalid revision range %s", arg);
1512}
1513
1514static int handle_dotdot_1(const char *arg, char *dotdot,
1515                           struct rev_info *revs, int flags,
1516                           int cant_be_filename,
1517                           struct object_context *a_oc,
1518                           struct object_context *b_oc)
1519{
1520        const char *a_name, *b_name;
1521        struct object_id a_oid, b_oid;
1522        struct object *a_obj, *b_obj;
1523        unsigned int a_flags, b_flags;
1524        int symmetric = 0;
1525        unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1526        unsigned int oc_flags = GET_OID_COMMITTISH | GET_OID_RECORD_PATH;
1527
1528        a_name = arg;
1529        if (!*a_name)
1530                a_name = "HEAD";
1531
1532        b_name = dotdot + 2;
1533        if (*b_name == '.') {
1534                symmetric = 1;
1535                b_name++;
1536        }
1537        if (!*b_name)
1538                b_name = "HEAD";
1539
1540        if (get_oid_with_context(a_name, oc_flags, &a_oid, a_oc) ||
1541            get_oid_with_context(b_name, oc_flags, &b_oid, b_oc))
1542                return -1;
1543
1544        if (!cant_be_filename) {
1545                *dotdot = '.';
1546                verify_non_filename(revs->prefix, arg);
1547                *dotdot = '\0';
1548        }
1549
1550        a_obj = parse_object(&a_oid);
1551        b_obj = parse_object(&b_oid);
1552        if (!a_obj || !b_obj)
1553                return dotdot_missing(arg, dotdot, revs, symmetric);
1554
1555        if (!symmetric) {
1556                /* just A..B */
1557                b_flags = flags;
1558                a_flags = flags_exclude;
1559        } else {
1560                /* A...B -- find merge bases between the two */
1561                struct commit *a, *b;
1562                struct commit_list *exclude;
1563
1564                a = lookup_commit_reference(&a_obj->oid);
1565                b = lookup_commit_reference(&b_obj->oid);
1566                if (!a || !b)
1567                        return dotdot_missing(arg, dotdot, revs, symmetric);
1568
1569                exclude = get_merge_bases(a, b);
1570                add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
1571                                     flags_exclude);
1572                add_pending_commit_list(revs, exclude, flags_exclude);
1573                free_commit_list(exclude);
1574
1575                b_flags = flags;
1576                a_flags = flags | SYMMETRIC_LEFT;
1577        }
1578
1579        a_obj->flags |= a_flags;
1580        b_obj->flags |= b_flags;
1581        add_rev_cmdline(revs, a_obj, a_name, REV_CMD_LEFT, a_flags);
1582        add_rev_cmdline(revs, b_obj, b_name, REV_CMD_RIGHT, b_flags);
1583        add_pending_object_with_path(revs, a_obj, a_name, a_oc->mode, a_oc->path);
1584        add_pending_object_with_path(revs, b_obj, b_name, b_oc->mode, b_oc->path);
1585        return 0;
1586}
1587
1588static int handle_dotdot(const char *arg,
1589                         struct rev_info *revs, int flags,
1590                         int cant_be_filename)
1591{
1592        struct object_context a_oc, b_oc;
1593        char *dotdot = strstr(arg, "..");
1594        int ret;
1595
1596        if (!dotdot)
1597                return -1;
1598
1599        memset(&a_oc, 0, sizeof(a_oc));
1600        memset(&b_oc, 0, sizeof(b_oc));
1601
1602        *dotdot = '\0';
1603        ret = handle_dotdot_1(arg, dotdot, revs, flags, cant_be_filename,
1604                              &a_oc, &b_oc);
1605        *dotdot = '.';
1606
1607        free(a_oc.path);
1608        free(b_oc.path);
1609
1610        return ret;
1611}
1612
1613int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1614{
1615        struct object_context oc;
1616        char *mark;
1617        struct object *object;
1618        struct object_id oid;
1619        int local_flags;
1620        const char *arg = arg_;
1621        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1622        unsigned get_sha1_flags = GET_OID_RECORD_PATH;
1623
1624        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1625
1626        if (!cant_be_filename && !strcmp(arg, "..")) {
1627                /*
1628                 * Just ".."?  That is not a range but the
1629                 * pathspec for the parent directory.
1630                 */
1631                return -1;
1632        }
1633
1634        if (!handle_dotdot(arg, revs, flags, revarg_opt))
1635                return 0;
1636
1637        mark = strstr(arg, "^@");
1638        if (mark && !mark[2]) {
1639                *mark = 0;
1640                if (add_parents_only(revs, arg, flags, 0))
1641                        return 0;
1642                *mark = '^';
1643        }
1644        mark = strstr(arg, "^!");
1645        if (mark && !mark[2]) {
1646                *mark = 0;
1647                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), 0))
1648                        *mark = '^';
1649        }
1650        mark = strstr(arg, "^-");
1651        if (mark) {
1652                int exclude_parent = 1;
1653
1654                if (mark[2]) {
1655                        char *end;
1656                        exclude_parent = strtoul(mark + 2, &end, 10);
1657                        if (*end != '\0' || !exclude_parent)
1658                                return -1;
1659                }
1660
1661                *mark = 0;
1662                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), exclude_parent))
1663                        *mark = '^';
1664        }
1665
1666        local_flags = 0;
1667        if (*arg == '^') {
1668                local_flags = UNINTERESTING | BOTTOM;
1669                arg++;
1670        }
1671
1672        if (revarg_opt & REVARG_COMMITTISH)
1673                get_sha1_flags |= GET_OID_COMMITTISH;
1674
1675        if (get_oid_with_context(arg, get_sha1_flags, &oid, &oc))
1676                return revs->ignore_missing ? 0 : -1;
1677        if (!cant_be_filename)
1678                verify_non_filename(revs->prefix, arg);
1679        object = get_reference(revs, arg, &oid, flags ^ local_flags);
1680        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1681        add_pending_object_with_path(revs, object, arg, oc.mode, oc.path);
1682        free(oc.path);
1683        return 0;
1684}
1685
1686static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1687                                     struct argv_array *prune)
1688{
1689        while (strbuf_getline(sb, stdin) != EOF)
1690                argv_array_push(prune, sb->buf);
1691}
1692
1693static void read_revisions_from_stdin(struct rev_info *revs,
1694                                      struct argv_array *prune)
1695{
1696        struct strbuf sb;
1697        int seen_dashdash = 0;
1698        int save_warning;
1699
1700        save_warning = warn_on_object_refname_ambiguity;
1701        warn_on_object_refname_ambiguity = 0;
1702
1703        strbuf_init(&sb, 1000);
1704        while (strbuf_getline(&sb, stdin) != EOF) {
1705                int len = sb.len;
1706                if (!len)
1707                        break;
1708                if (sb.buf[0] == '-') {
1709                        if (len == 2 && sb.buf[1] == '-') {
1710                                seen_dashdash = 1;
1711                                break;
1712                        }
1713                        die("options not supported in --stdin mode");
1714                }
1715                if (handle_revision_arg(sb.buf, revs, 0,
1716                                        REVARG_CANNOT_BE_FILENAME))
1717                        die("bad revision '%s'", sb.buf);
1718        }
1719        if (seen_dashdash)
1720                read_pathspec_from_stdin(revs, &sb, prune);
1721
1722        strbuf_release(&sb);
1723        warn_on_object_refname_ambiguity = save_warning;
1724}
1725
1726static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1727{
1728        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1729}
1730
1731static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1732{
1733        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1734}
1735
1736static void add_message_grep(struct rev_info *revs, const char *pattern)
1737{
1738        add_grep(revs, pattern, GREP_PATTERN_BODY);
1739}
1740
1741static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1742                               int *unkc, const char **unkv)
1743{
1744        const char *arg = argv[0];
1745        const char *optarg;
1746        int argcount;
1747
1748        /* pseudo revision arguments */
1749        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1750            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1751            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1752            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1753            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1754            !strcmp(arg, "--indexed-objects") ||
1755            starts_with(arg, "--exclude=") ||
1756            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1757            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1758        {
1759                unkv[(*unkc)++] = arg;
1760                return 1;
1761        }
1762
1763        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1764                revs->max_count = atoi(optarg);
1765                revs->no_walk = 0;
1766                return argcount;
1767        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1768                revs->skip_count = atoi(optarg);
1769                return argcount;
1770        } else if ((*arg == '-') && isdigit(arg[1])) {
1771                /* accept -<digit>, like traditional "head" */
1772                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1773                    revs->max_count < 0)
1774                        die("'%s': not a non-negative integer", arg + 1);
1775                revs->no_walk = 0;
1776        } else if (!strcmp(arg, "-n")) {
1777                if (argc <= 1)
1778                        return error("-n requires an argument");
1779                revs->max_count = atoi(argv[1]);
1780                revs->no_walk = 0;
1781                return 2;
1782        } else if (skip_prefix(arg, "-n", &optarg)) {
1783                revs->max_count = atoi(optarg);
1784                revs->no_walk = 0;
1785        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1786                revs->max_age = atoi(optarg);
1787                return argcount;
1788        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1789                revs->max_age = approxidate(optarg);
1790                return argcount;
1791        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1792                revs->max_age = approxidate(optarg);
1793                return argcount;
1794        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1795                revs->min_age = atoi(optarg);
1796                return argcount;
1797        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1798                revs->min_age = approxidate(optarg);
1799                return argcount;
1800        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1801                revs->min_age = approxidate(optarg);
1802                return argcount;
1803        } else if (!strcmp(arg, "--first-parent")) {
1804                revs->first_parent_only = 1;
1805        } else if (!strcmp(arg, "--ancestry-path")) {
1806                revs->ancestry_path = 1;
1807                revs->simplify_history = 0;
1808                revs->limited = 1;
1809        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1810                init_reflog_walk(&revs->reflog_info);
1811        } else if (!strcmp(arg, "--default")) {
1812                if (argc <= 1)
1813                        return error("bad --default argument");
1814                revs->def = argv[1];
1815                return 2;
1816        } else if (!strcmp(arg, "--merge")) {
1817                revs->show_merge = 1;
1818        } else if (!strcmp(arg, "--topo-order")) {
1819                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1820                revs->topo_order = 1;
1821        } else if (!strcmp(arg, "--simplify-merges")) {
1822                revs->simplify_merges = 1;
1823                revs->topo_order = 1;
1824                revs->rewrite_parents = 1;
1825                revs->simplify_history = 0;
1826                revs->limited = 1;
1827        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1828                revs->simplify_merges = 1;
1829                revs->topo_order = 1;
1830                revs->rewrite_parents = 1;
1831                revs->simplify_history = 0;
1832                revs->simplify_by_decoration = 1;
1833                revs->limited = 1;
1834                revs->prune = 1;
1835                load_ref_decorations(DECORATE_SHORT_REFS);
1836        } else if (!strcmp(arg, "--date-order")) {
1837                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1838                revs->topo_order = 1;
1839        } else if (!strcmp(arg, "--author-date-order")) {
1840                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1841                revs->topo_order = 1;
1842        } else if (!strcmp(arg, "--early-output")) {
1843                revs->early_output = 100;
1844                revs->topo_order = 1;
1845        } else if (skip_prefix(arg, "--early-output=", &optarg)) {
1846                if (strtoul_ui(optarg, 10, &revs->early_output) < 0)
1847                        die("'%s': not a non-negative integer", optarg);
1848                revs->topo_order = 1;
1849        } else if (!strcmp(arg, "--parents")) {
1850                revs->rewrite_parents = 1;
1851                revs->print_parents = 1;
1852        } else if (!strcmp(arg, "--dense")) {
1853                revs->dense = 1;
1854        } else if (!strcmp(arg, "--sparse")) {
1855                revs->dense = 0;
1856        } else if (!strcmp(arg, "--show-all")) {
1857                revs->show_all = 1;
1858        } else if (!strcmp(arg, "--remove-empty")) {
1859                revs->remove_empty_trees = 1;
1860        } else if (!strcmp(arg, "--merges")) {
1861                revs->min_parents = 2;
1862        } else if (!strcmp(arg, "--no-merges")) {
1863                revs->max_parents = 1;
1864        } else if (skip_prefix(arg, "--min-parents=", &optarg)) {
1865                revs->min_parents = atoi(optarg);
1866        } else if (!strcmp(arg, "--no-min-parents")) {
1867                revs->min_parents = 0;
1868        } else if (skip_prefix(arg, "--max-parents=", &optarg)) {
1869                revs->max_parents = atoi(optarg);
1870        } else if (!strcmp(arg, "--no-max-parents")) {
1871                revs->max_parents = -1;
1872        } else if (!strcmp(arg, "--boundary")) {
1873                revs->boundary = 1;
1874        } else if (!strcmp(arg, "--left-right")) {
1875                revs->left_right = 1;
1876        } else if (!strcmp(arg, "--left-only")) {
1877                if (revs->right_only)
1878                        die("--left-only is incompatible with --right-only"
1879                            " or --cherry");
1880                revs->left_only = 1;
1881        } else if (!strcmp(arg, "--right-only")) {
1882                if (revs->left_only)
1883                        die("--right-only is incompatible with --left-only");
1884                revs->right_only = 1;
1885        } else if (!strcmp(arg, "--cherry")) {
1886                if (revs->left_only)
1887                        die("--cherry is incompatible with --left-only");
1888                revs->cherry_mark = 1;
1889                revs->right_only = 1;
1890                revs->max_parents = 1;
1891                revs->limited = 1;
1892        } else if (!strcmp(arg, "--count")) {
1893                revs->count = 1;
1894        } else if (!strcmp(arg, "--cherry-mark")) {
1895                if (revs->cherry_pick)
1896                        die("--cherry-mark is incompatible with --cherry-pick");
1897                revs->cherry_mark = 1;
1898                revs->limited = 1; /* needs limit_list() */
1899        } else if (!strcmp(arg, "--cherry-pick")) {
1900                if (revs->cherry_mark)
1901                        die("--cherry-pick is incompatible with --cherry-mark");
1902                revs->cherry_pick = 1;
1903                revs->limited = 1;
1904        } else if (!strcmp(arg, "--objects")) {
1905                revs->tag_objects = 1;
1906                revs->tree_objects = 1;
1907                revs->blob_objects = 1;
1908        } else if (!strcmp(arg, "--objects-edge")) {
1909                revs->tag_objects = 1;
1910                revs->tree_objects = 1;
1911                revs->blob_objects = 1;
1912                revs->edge_hint = 1;
1913        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1914                revs->tag_objects = 1;
1915                revs->tree_objects = 1;
1916                revs->blob_objects = 1;
1917                revs->edge_hint = 1;
1918                revs->edge_hint_aggressive = 1;
1919        } else if (!strcmp(arg, "--verify-objects")) {
1920                revs->tag_objects = 1;
1921                revs->tree_objects = 1;
1922                revs->blob_objects = 1;
1923                revs->verify_objects = 1;
1924        } else if (!strcmp(arg, "--unpacked")) {
1925                revs->unpacked = 1;
1926        } else if (starts_with(arg, "--unpacked=")) {
1927                die("--unpacked=<packfile> no longer supported.");
1928        } else if (!strcmp(arg, "-r")) {
1929                revs->diff = 1;
1930                revs->diffopt.flags.recursive = 1;
1931        } else if (!strcmp(arg, "-t")) {
1932                revs->diff = 1;
1933                revs->diffopt.flags.recursive = 1;
1934                revs->diffopt.flags.tree_in_recursive = 1;
1935        } else if (!strcmp(arg, "-m")) {
1936                revs->ignore_merges = 0;
1937        } else if (!strcmp(arg, "-c")) {
1938                revs->diff = 1;
1939                revs->dense_combined_merges = 0;
1940                revs->combine_merges = 1;
1941        } else if (!strcmp(arg, "--cc")) {
1942                revs->diff = 1;
1943                revs->dense_combined_merges = 1;
1944                revs->combine_merges = 1;
1945        } else if (!strcmp(arg, "-v")) {
1946                revs->verbose_header = 1;
1947        } else if (!strcmp(arg, "--pretty")) {
1948                revs->verbose_header = 1;
1949                revs->pretty_given = 1;
1950                get_commit_format(NULL, revs);
1951        } else if (skip_prefix(arg, "--pretty=", &optarg) ||
1952                   skip_prefix(arg, "--format=", &optarg)) {
1953                /*
1954                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1955                 * not allowed, since the argument is optional.
1956                 */
1957                revs->verbose_header = 1;
1958                revs->pretty_given = 1;
1959                get_commit_format(optarg, revs);
1960        } else if (!strcmp(arg, "--expand-tabs")) {
1961                revs->expand_tabs_in_log = 8;
1962        } else if (!strcmp(arg, "--no-expand-tabs")) {
1963                revs->expand_tabs_in_log = 0;
1964        } else if (skip_prefix(arg, "--expand-tabs=", &arg)) {
1965                int val;
1966                if (strtol_i(arg, 10, &val) < 0 || val < 0)
1967                        die("'%s': not a non-negative integer", arg);
1968                revs->expand_tabs_in_log = val;
1969        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1970                revs->show_notes = 1;
1971                revs->show_notes_given = 1;
1972                revs->notes_opt.use_default_notes = 1;
1973        } else if (!strcmp(arg, "--show-signature")) {
1974                revs->show_signature = 1;
1975        } else if (!strcmp(arg, "--no-show-signature")) {
1976                revs->show_signature = 0;
1977        } else if (!strcmp(arg, "--show-linear-break")) {
1978                revs->break_bar = "                    ..........";
1979                revs->track_linear = 1;
1980                revs->track_first_time = 1;
1981        } else if (skip_prefix(arg, "--show-linear-break=", &optarg)) {
1982                revs->break_bar = xstrdup(optarg);
1983                revs->track_linear = 1;
1984                revs->track_first_time = 1;
1985        } else if (skip_prefix(arg, "--show-notes=", &optarg) ||
1986                   skip_prefix(arg, "--notes=", &optarg)) {
1987                struct strbuf buf = STRBUF_INIT;
1988                revs->show_notes = 1;
1989                revs->show_notes_given = 1;
1990                if (starts_with(arg, "--show-notes=") &&
1991                    revs->notes_opt.use_default_notes < 0)
1992                        revs->notes_opt.use_default_notes = 1;
1993                strbuf_addstr(&buf, optarg);
1994                expand_notes_ref(&buf);
1995                string_list_append(&revs->notes_opt.extra_notes_refs,
1996                                   strbuf_detach(&buf, NULL));
1997        } else if (!strcmp(arg, "--no-notes")) {
1998                revs->show_notes = 0;
1999                revs->show_notes_given = 1;
2000                revs->notes_opt.use_default_notes = -1;
2001                /* we have been strdup'ing ourselves, so trick
2002                 * string_list into free()ing strings */
2003                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
2004                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
2005                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
2006        } else if (!strcmp(arg, "--standard-notes")) {
2007                revs->show_notes_given = 1;
2008                revs->notes_opt.use_default_notes = 1;
2009        } else if (!strcmp(arg, "--no-standard-notes")) {
2010                revs->notes_opt.use_default_notes = 0;
2011        } else if (!strcmp(arg, "--oneline")) {
2012                revs->verbose_header = 1;
2013                get_commit_format("oneline", revs);
2014                revs->pretty_given = 1;
2015                revs->abbrev_commit = 1;
2016        } else if (!strcmp(arg, "--graph")) {
2017                revs->topo_order = 1;
2018                revs->rewrite_parents = 1;
2019                revs->graph = graph_init(revs);
2020        } else if (!strcmp(arg, "--root")) {
2021                revs->show_root_diff = 1;
2022        } else if (!strcmp(arg, "--no-commit-id")) {
2023                revs->no_commit_id = 1;
2024        } else if (!strcmp(arg, "--always")) {
2025                revs->always_show_header = 1;
2026        } else if (!strcmp(arg, "--no-abbrev")) {
2027                revs->abbrev = 0;
2028        } else if (!strcmp(arg, "--abbrev")) {
2029                revs->abbrev = DEFAULT_ABBREV;
2030        } else if (skip_prefix(arg, "--abbrev=", &optarg)) {
2031                revs->abbrev = strtoul(optarg, NULL, 10);
2032                if (revs->abbrev < MINIMUM_ABBREV)
2033                        revs->abbrev = MINIMUM_ABBREV;
2034                else if (revs->abbrev > 40)
2035                        revs->abbrev = 40;
2036        } else if (!strcmp(arg, "--abbrev-commit")) {
2037                revs->abbrev_commit = 1;
2038                revs->abbrev_commit_given = 1;
2039        } else if (!strcmp(arg, "--no-abbrev-commit")) {
2040                revs->abbrev_commit = 0;
2041        } else if (!strcmp(arg, "--full-diff")) {
2042                revs->diff = 1;
2043                revs->full_diff = 1;
2044        } else if (!strcmp(arg, "--full-history")) {
2045                revs->simplify_history = 0;
2046        } else if (!strcmp(arg, "--relative-date")) {
2047                revs->date_mode.type = DATE_RELATIVE;
2048                revs->date_mode_explicit = 1;
2049        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
2050                parse_date_format(optarg, &revs->date_mode);
2051                revs->date_mode_explicit = 1;
2052                return argcount;
2053        } else if (!strcmp(arg, "--log-size")) {
2054                revs->show_log_size = 1;
2055        }
2056        /*
2057         * Grepping the commit log
2058         */
2059        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
2060                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
2061                return argcount;
2062        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
2063                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
2064                return argcount;
2065        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
2066                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
2067                return argcount;
2068        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
2069                add_message_grep(revs, optarg);
2070                return argcount;
2071        } else if (!strcmp(arg, "--grep-debug")) {
2072                revs->grep_filter.debug = 1;
2073        } else if (!strcmp(arg, "--basic-regexp")) {
2074                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_BRE;
2075        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
2076                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_ERE;
2077        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
2078                revs->grep_filter.ignore_case = 1;
2079                revs->diffopt.flags.pickaxe_ignore_case = 1;
2080        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
2081                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
2082        } else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
2083                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
2084        } else if (!strcmp(arg, "--all-match")) {
2085                revs->grep_filter.all_match = 1;
2086        } else if (!strcmp(arg, "--invert-grep")) {
2087                revs->invert_grep = 1;
2088        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
2089                if (strcmp(optarg, "none"))
2090                        git_log_output_encoding = xstrdup(optarg);
2091                else
2092                        git_log_output_encoding = "";
2093                return argcount;
2094        } else if (!strcmp(arg, "--reverse")) {
2095                revs->reverse ^= 1;
2096        } else if (!strcmp(arg, "--children")) {
2097                revs->children.name = "children";
2098                revs->limited = 1;
2099        } else if (!strcmp(arg, "--ignore-missing")) {
2100                revs->ignore_missing = 1;
2101        } else {
2102                int opts = diff_opt_parse(&revs->diffopt, argv, argc, revs->prefix);
2103                if (!opts)
2104                        unkv[(*unkc)++] = arg;
2105                return opts;
2106        }
2107        if (revs->graph && revs->track_linear)
2108                die("--show-linear-break and --graph are incompatible");
2109
2110        return 1;
2111}
2112
2113void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2114                        const struct option *options,
2115                        const char * const usagestr[])
2116{
2117        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2118                                    &ctx->cpidx, ctx->out);
2119        if (n <= 0) {
2120                error("unknown option `%s'", ctx->argv[0]);
2121                usage_with_options(usagestr, options);
2122        }
2123        ctx->argv += n;
2124        ctx->argc -= n;
2125}
2126
2127static int for_each_bisect_ref(struct ref_store *refs, each_ref_fn fn,
2128                               void *cb_data, const char *term)
2129{
2130        struct strbuf bisect_refs = STRBUF_INIT;
2131        int status;
2132        strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
2133        status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data, 0);
2134        strbuf_release(&bisect_refs);
2135        return status;
2136}
2137
2138static int for_each_bad_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2139{
2140        return for_each_bisect_ref(refs, fn, cb_data, term_bad);
2141}
2142
2143static int for_each_good_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2144{
2145        return for_each_bisect_ref(refs, fn, cb_data, term_good);
2146}
2147
2148static int handle_revision_pseudo_opt(const char *submodule,
2149                                struct rev_info *revs,
2150                                int argc, const char **argv, int *flags)
2151{
2152        const char *arg = argv[0];
2153        const char *optarg;
2154        struct ref_store *refs;
2155        int argcount;
2156
2157        if (submodule) {
2158                /*
2159                 * We need some something like get_submodule_worktrees()
2160                 * before we can go through all worktrees of a submodule,
2161                 * .e.g with adding all HEADs from --all, which is not
2162                 * supported right now, so stick to single worktree.
2163                 */
2164                if (!revs->single_worktree)
2165                        die("BUG: --single-worktree cannot be used together with submodule");
2166                refs = get_submodule_ref_store(submodule);
2167        } else
2168                refs = get_main_ref_store();
2169
2170        /*
2171         * NOTE!
2172         *
2173         * Commands like "git shortlog" will not accept the options below
2174         * unless parse_revision_opt queues them (as opposed to erroring
2175         * out).
2176         *
2177         * When implementing your new pseudo-option, remember to
2178         * register it in the list at the top of handle_revision_opt.
2179         */
2180        if (!strcmp(arg, "--all")) {
2181                handle_refs(refs, revs, *flags, refs_for_each_ref);
2182                handle_refs(refs, revs, *flags, refs_head_ref);
2183                if (!revs->single_worktree) {
2184                        struct all_refs_cb cb;
2185
2186                        init_all_refs_cb(&cb, revs, *flags);
2187                        other_head_refs(handle_one_ref, &cb);
2188                }
2189                clear_ref_exclusion(&revs->ref_excludes);
2190        } else if (!strcmp(arg, "--branches")) {
2191                handle_refs(refs, revs, *flags, refs_for_each_branch_ref);
2192                clear_ref_exclusion(&revs->ref_excludes);
2193        } else if (!strcmp(arg, "--bisect")) {
2194                read_bisect_terms(&term_bad, &term_good);
2195                handle_refs(refs, revs, *flags, for_each_bad_bisect_ref);
2196                handle_refs(refs, revs, *flags ^ (UNINTERESTING | BOTTOM),
2197                            for_each_good_bisect_ref);
2198                revs->bisect = 1;
2199        } else if (!strcmp(arg, "--tags")) {
2200                handle_refs(refs, revs, *flags, refs_for_each_tag_ref);
2201                clear_ref_exclusion(&revs->ref_excludes);
2202        } else if (!strcmp(arg, "--remotes")) {
2203                handle_refs(refs, revs, *flags, refs_for_each_remote_ref);
2204                clear_ref_exclusion(&revs->ref_excludes);
2205        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2206                struct all_refs_cb cb;
2207                init_all_refs_cb(&cb, revs, *flags);
2208                for_each_glob_ref(handle_one_ref, optarg, &cb);
2209                clear_ref_exclusion(&revs->ref_excludes);
2210                return argcount;
2211        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2212                add_ref_exclusion(&revs->ref_excludes, optarg);
2213                return argcount;
2214        } else if (skip_prefix(arg, "--branches=", &optarg)) {
2215                struct all_refs_cb cb;
2216                init_all_refs_cb(&cb, revs, *flags);
2217                for_each_glob_ref_in(handle_one_ref, optarg, "refs/heads/", &cb);
2218                clear_ref_exclusion(&revs->ref_excludes);
2219        } else if (skip_prefix(arg, "--tags=", &optarg)) {
2220                struct all_refs_cb cb;
2221                init_all_refs_cb(&cb, revs, *flags);
2222                for_each_glob_ref_in(handle_one_ref, optarg, "refs/tags/", &cb);
2223                clear_ref_exclusion(&revs->ref_excludes);
2224        } else if (skip_prefix(arg, "--remotes=", &optarg)) {
2225                struct all_refs_cb cb;
2226                init_all_refs_cb(&cb, revs, *flags);
2227                for_each_glob_ref_in(handle_one_ref, optarg, "refs/remotes/", &cb);
2228                clear_ref_exclusion(&revs->ref_excludes);
2229        } else if (!strcmp(arg, "--reflog")) {
2230                add_reflogs_to_pending(revs, *flags);
2231        } else if (!strcmp(arg, "--indexed-objects")) {
2232                add_index_objects_to_pending(revs, *flags);
2233        } else if (!strcmp(arg, "--not")) {
2234                *flags ^= UNINTERESTING | BOTTOM;
2235        } else if (!strcmp(arg, "--no-walk")) {
2236                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2237        } else if (skip_prefix(arg, "--no-walk=", &optarg)) {
2238                /*
2239                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2240                 * not allowed, since the argument is optional.
2241                 */
2242                if (!strcmp(optarg, "sorted"))
2243                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2244                else if (!strcmp(optarg, "unsorted"))
2245                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2246                else
2247                        return error("invalid argument to --no-walk");
2248        } else if (!strcmp(arg, "--do-walk")) {
2249                revs->no_walk = 0;
2250        } else if (!strcmp(arg, "--single-worktree")) {
2251                revs->single_worktree = 1;
2252        } else {
2253                return 0;
2254        }
2255
2256        return 1;
2257}
2258
2259static void NORETURN diagnose_missing_default(const char *def)
2260{
2261        int flags;
2262        const char *refname;
2263
2264        refname = resolve_ref_unsafe(def, 0, NULL, &flags);
2265        if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
2266                die(_("your current branch appears to be broken"));
2267
2268        skip_prefix(refname, "refs/heads/", &refname);
2269        die(_("your current branch '%s' does not have any commits yet"),
2270            refname);
2271}
2272
2273/*
2274 * Parse revision information, filling in the "rev_info" structure,
2275 * and removing the used arguments from the argument list.
2276 *
2277 * Returns the number of arguments left that weren't recognized
2278 * (which are also moved to the head of the argument list)
2279 */
2280int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2281{
2282        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2283        struct argv_array prune_data = ARGV_ARRAY_INIT;
2284        const char *submodule = NULL;
2285
2286        if (opt)
2287                submodule = opt->submodule;
2288
2289        /* First, search for "--" */
2290        if (opt && opt->assume_dashdash) {
2291                seen_dashdash = 1;
2292        } else {
2293                seen_dashdash = 0;
2294                for (i = 1; i < argc; i++) {
2295                        const char *arg = argv[i];
2296                        if (strcmp(arg, "--"))
2297                                continue;
2298                        argv[i] = NULL;
2299                        argc = i;
2300                        if (argv[i + 1])
2301                                argv_array_pushv(&prune_data, argv + i + 1);
2302                        seen_dashdash = 1;
2303                        break;
2304                }
2305        }
2306
2307        /* Second, deal with arguments and options */
2308        flags = 0;
2309        revarg_opt = opt ? opt->revarg_opt : 0;
2310        if (seen_dashdash)
2311                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2312        read_from_stdin = 0;
2313        for (left = i = 1; i < argc; i++) {
2314                const char *arg = argv[i];
2315                if (*arg == '-') {
2316                        int opts;
2317
2318                        opts = handle_revision_pseudo_opt(submodule,
2319                                                revs, argc - i, argv + i,
2320                                                &flags);
2321                        if (opts > 0) {
2322                                i += opts - 1;
2323                                continue;
2324                        }
2325
2326                        if (!strcmp(arg, "--stdin")) {
2327                                if (revs->disable_stdin) {
2328                                        argv[left++] = arg;
2329                                        continue;
2330                                }
2331                                if (read_from_stdin++)
2332                                        die("--stdin given twice?");
2333                                read_revisions_from_stdin(revs, &prune_data);
2334                                continue;
2335                        }
2336
2337                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2338                        if (opts > 0) {
2339                                i += opts - 1;
2340                                continue;
2341                        }
2342                        if (opts < 0)
2343                                exit(128);
2344                        continue;
2345                }
2346
2347
2348                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2349                        int j;
2350                        if (seen_dashdash || *arg == '^')
2351                                die("bad revision '%s'", arg);
2352
2353                        /* If we didn't have a "--":
2354                         * (1) all filenames must exist;
2355                         * (2) all rev-args must not be interpretable
2356                         *     as a valid filename.
2357                         * but the latter we have checked in the main loop.
2358                         */
2359                        for (j = i; j < argc; j++)
2360                                verify_filename(revs->prefix, argv[j], j == i);
2361
2362                        argv_array_pushv(&prune_data, argv + i);
2363                        break;
2364                }
2365                else
2366                        got_rev_arg = 1;
2367        }
2368
2369        if (prune_data.argc) {
2370                /*
2371                 * If we need to introduce the magic "a lone ':' means no
2372                 * pathspec whatsoever", here is the place to do so.
2373                 *
2374                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2375                 *      prune_data.nr = 0;
2376                 *      prune_data.alloc = 0;
2377                 *      free(prune_data.path);
2378                 *      prune_data.path = NULL;
2379                 * } else {
2380                 *      terminate prune_data.alloc with NULL and
2381                 *      call init_pathspec() to set revs->prune_data here.
2382                 * }
2383                 */
2384                parse_pathspec(&revs->prune_data, 0, 0,
2385                               revs->prefix, prune_data.argv);
2386        }
2387        argv_array_clear(&prune_data);
2388
2389        if (revs->def == NULL)
2390                revs->def = opt ? opt->def : NULL;
2391        if (opt && opt->tweak)
2392                opt->tweak(revs, opt);
2393        if (revs->show_merge)
2394                prepare_show_merge(revs);
2395        if (revs->def && !revs->pending.nr && !revs->rev_input_given && !got_rev_arg) {
2396                struct object_id oid;
2397                struct object *object;
2398                struct object_context oc;
2399                if (get_oid_with_context(revs->def, 0, &oid, &oc))
2400                        diagnose_missing_default(revs->def);
2401                object = get_reference(revs, revs->def, &oid, 0);
2402                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2403        }
2404
2405        /* Did the user ask for any diff output? Run the diff! */
2406        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2407                revs->diff = 1;
2408
2409        /* Pickaxe, diff-filter and rename following need diffs */
2410        if (revs->diffopt.pickaxe ||
2411            revs->diffopt.filter ||
2412            revs->diffopt.flags.follow_renames)
2413                revs->diff = 1;
2414
2415        if (revs->topo_order)
2416                revs->limited = 1;
2417
2418        if (revs->prune_data.nr) {
2419                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2420                /* Can't prune commits with rename following: the paths change.. */
2421                if (!revs->diffopt.flags.follow_renames)
2422                        revs->prune = 1;
2423                if (!revs->full_diff)
2424                        copy_pathspec(&revs->diffopt.pathspec,
2425                                      &revs->prune_data);
2426        }
2427        if (revs->combine_merges)
2428                revs->ignore_merges = 0;
2429        revs->diffopt.abbrev = revs->abbrev;
2430
2431        if (revs->line_level_traverse) {
2432                revs->limited = 1;
2433                revs->topo_order = 1;
2434        }
2435
2436        diff_setup_done(&revs->diffopt);
2437
2438        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2439                                 &revs->grep_filter);
2440        compile_grep_patterns(&revs->grep_filter);
2441
2442        if (revs->reverse && revs->reflog_info)
2443                die("cannot combine --reverse with --walk-reflogs");
2444        if (revs->reflog_info && revs->limited)
2445                die("cannot combine --walk-reflogs with history-limiting options");
2446        if (revs->rewrite_parents && revs->children.name)
2447                die("cannot combine --parents and --children");
2448
2449        /*
2450         * Limitations on the graph functionality
2451         */
2452        if (revs->reverse && revs->graph)
2453                die("cannot combine --reverse with --graph");
2454
2455        if (revs->reflog_info && revs->graph)
2456                die("cannot combine --walk-reflogs with --graph");
2457        if (revs->no_walk && revs->graph)
2458                die("cannot combine --no-walk with --graph");
2459        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2460                die("cannot use --grep-reflog without --walk-reflogs");
2461
2462        if (revs->first_parent_only && revs->bisect)
2463                die(_("--first-parent is incompatible with --bisect"));
2464
2465        if (revs->expand_tabs_in_log < 0)
2466                revs->expand_tabs_in_log = revs->expand_tabs_in_log_default;
2467
2468        return left;
2469}
2470
2471static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2472{
2473        struct commit_list *l = xcalloc(1, sizeof(*l));
2474
2475        l->item = child;
2476        l->next = add_decoration(&revs->children, &parent->object, l);
2477}
2478
2479static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2480{
2481        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2482        struct commit_list **pp, *p;
2483        int surviving_parents;
2484
2485        /* Examine existing parents while marking ones we have seen... */
2486        pp = &commit->parents;
2487        surviving_parents = 0;
2488        while ((p = *pp) != NULL) {
2489                struct commit *parent = p->item;
2490                if (parent->object.flags & TMP_MARK) {
2491                        *pp = p->next;
2492                        if (ts)
2493                                compact_treesame(revs, commit, surviving_parents);
2494                        continue;
2495                }
2496                parent->object.flags |= TMP_MARK;
2497                surviving_parents++;
2498                pp = &p->next;
2499        }
2500        /* clear the temporary mark */
2501        for (p = commit->parents; p; p = p->next) {
2502                p->item->object.flags &= ~TMP_MARK;
2503        }
2504        /* no update_treesame() - removing duplicates can't affect TREESAME */
2505        return surviving_parents;
2506}
2507
2508struct merge_simplify_state {
2509        struct commit *simplified;
2510};
2511
2512static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2513{
2514        struct merge_simplify_state *st;
2515
2516        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2517        if (!st) {
2518                st = xcalloc(1, sizeof(*st));
2519                add_decoration(&revs->merge_simplification, &commit->object, st);
2520        }
2521        return st;
2522}
2523
2524static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2525{
2526        struct commit_list *h = reduce_heads(commit->parents);
2527        int i = 0, marked = 0;
2528        struct commit_list *po, *pn;
2529
2530        /* Want these for sanity-checking only */
2531        int orig_cnt = commit_list_count(commit->parents);
2532        int cnt = commit_list_count(h);
2533
2534        /*
2535         * Not ready to remove items yet, just mark them for now, based
2536         * on the output of reduce_heads(). reduce_heads outputs the reduced
2537         * set in its original order, so this isn't too hard.
2538         */
2539        po = commit->parents;
2540        pn = h;
2541        while (po) {
2542                if (pn && po->item == pn->item) {
2543                        pn = pn->next;
2544                        i++;
2545                } else {
2546                        po->item->object.flags |= TMP_MARK;
2547                        marked++;
2548                }
2549                po=po->next;
2550        }
2551
2552        if (i != cnt || cnt+marked != orig_cnt)
2553                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2554
2555        free_commit_list(h);
2556
2557        return marked;
2558}
2559
2560static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2561{
2562        struct commit_list *p;
2563        int marked = 0;
2564
2565        for (p = commit->parents; p; p = p->next) {
2566                struct commit *parent = p->item;
2567                if (!parent->parents && (parent->object.flags & TREESAME)) {
2568                        parent->object.flags |= TMP_MARK;
2569                        marked++;
2570                }
2571        }
2572
2573        return marked;
2574}
2575
2576/*
2577 * Awkward naming - this means one parent we are TREESAME to.
2578 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2579 * empty tree). Better name suggestions?
2580 */
2581static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2582{
2583        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2584        struct commit *unmarked = NULL, *marked = NULL;
2585        struct commit_list *p;
2586        unsigned n;
2587
2588        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2589                if (ts->treesame[n]) {
2590                        if (p->item->object.flags & TMP_MARK) {
2591                                if (!marked)
2592                                        marked = p->item;
2593                        } else {
2594                                if (!unmarked) {
2595                                        unmarked = p->item;
2596                                        break;
2597                                }
2598                        }
2599                }
2600        }
2601
2602        /*
2603         * If we are TREESAME to a marked-for-deletion parent, but not to any
2604         * unmarked parents, unmark the first TREESAME parent. This is the
2605         * parent that the default simplify_history==1 scan would have followed,
2606         * and it doesn't make sense to omit that path when asking for a
2607         * simplified full history. Retaining it improves the chances of
2608         * understanding odd missed merges that took an old version of a file.
2609         *
2610         * Example:
2611         *
2612         *   I--------*X       A modified the file, but mainline merge X used
2613         *    \       /        "-s ours", so took the version from I. X is
2614         *     `-*A--'         TREESAME to I and !TREESAME to A.
2615         *
2616         * Default log from X would produce "I". Without this check,
2617         * --full-history --simplify-merges would produce "I-A-X", showing
2618         * the merge commit X and that it changed A, but not making clear that
2619         * it had just taken the I version. With this check, the topology above
2620         * is retained.
2621         *
2622         * Note that it is possible that the simplification chooses a different
2623         * TREESAME parent from the default, in which case this test doesn't
2624         * activate, and we _do_ drop the default parent. Example:
2625         *
2626         *   I------X         A modified the file, but it was reverted in B,
2627         *    \    /          meaning mainline merge X is TREESAME to both
2628         *    *A-*B           parents.
2629         *
2630         * Default log would produce "I" by following the first parent;
2631         * --full-history --simplify-merges will produce "I-A-B". But this is a
2632         * reasonable result - it presents a logical full history leading from
2633         * I to X, and X is not an important merge.
2634         */
2635        if (!unmarked && marked) {
2636                marked->object.flags &= ~TMP_MARK;
2637                return 1;
2638        }
2639
2640        return 0;
2641}
2642
2643static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2644{
2645        struct commit_list **pp, *p;
2646        int nth_parent, removed = 0;
2647
2648        pp = &commit->parents;
2649        nth_parent = 0;
2650        while ((p = *pp) != NULL) {
2651                struct commit *parent = p->item;
2652                if (parent->object.flags & TMP_MARK) {
2653                        parent->object.flags &= ~TMP_MARK;
2654                        *pp = p->next;
2655                        free(p);
2656                        removed++;
2657                        compact_treesame(revs, commit, nth_parent);
2658                        continue;
2659                }
2660                pp = &p->next;
2661                nth_parent++;
2662        }
2663
2664        /* Removing parents can only increase TREESAMEness */
2665        if (removed && !(commit->object.flags & TREESAME))
2666                update_treesame(revs, commit);
2667
2668        return nth_parent;
2669}
2670
2671static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2672{
2673        struct commit_list *p;
2674        struct commit *parent;
2675        struct merge_simplify_state *st, *pst;
2676        int cnt;
2677
2678        st = locate_simplify_state(revs, commit);
2679
2680        /*
2681         * Have we handled this one?
2682         */
2683        if (st->simplified)
2684                return tail;
2685
2686        /*
2687         * An UNINTERESTING commit simplifies to itself, so does a
2688         * root commit.  We do not rewrite parents of such commit
2689         * anyway.
2690         */
2691        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2692                st->simplified = commit;
2693                return tail;
2694        }
2695
2696        /*
2697         * Do we know what commit all of our parents that matter
2698         * should be rewritten to?  Otherwise we are not ready to
2699         * rewrite this one yet.
2700         */
2701        for (cnt = 0, p = commit->parents; p; p = p->next) {
2702                pst = locate_simplify_state(revs, p->item);
2703                if (!pst->simplified) {
2704                        tail = &commit_list_insert(p->item, tail)->next;
2705                        cnt++;
2706                }
2707                if (revs->first_parent_only)
2708                        break;
2709        }
2710        if (cnt) {
2711                tail = &commit_list_insert(commit, tail)->next;
2712                return tail;
2713        }
2714
2715        /*
2716         * Rewrite our list of parents. Note that this cannot
2717         * affect our TREESAME flags in any way - a commit is
2718         * always TREESAME to its simplification.
2719         */
2720        for (p = commit->parents; p; p = p->next) {
2721                pst = locate_simplify_state(revs, p->item);
2722                p->item = pst->simplified;
2723                if (revs->first_parent_only)
2724                        break;
2725        }
2726
2727        if (revs->first_parent_only)
2728                cnt = 1;
2729        else
2730                cnt = remove_duplicate_parents(revs, commit);
2731
2732        /*
2733         * It is possible that we are a merge and one side branch
2734         * does not have any commit that touches the given paths;
2735         * in such a case, the immediate parent from that branch
2736         * will be rewritten to be the merge base.
2737         *
2738         *      o----X          X: the commit we are looking at;
2739         *     /    /           o: a commit that touches the paths;
2740         * ---o----'
2741         *
2742         * Further, a merge of an independent branch that doesn't
2743         * touch the path will reduce to a treesame root parent:
2744         *
2745         *  ----o----X          X: the commit we are looking at;
2746         *          /           o: a commit that touches the paths;
2747         *         r            r: a root commit not touching the paths
2748         *
2749         * Detect and simplify both cases.
2750         */
2751        if (1 < cnt) {
2752                int marked = mark_redundant_parents(revs, commit);
2753                marked += mark_treesame_root_parents(revs, commit);
2754                if (marked)
2755                        marked -= leave_one_treesame_to_parent(revs, commit);
2756                if (marked)
2757                        cnt = remove_marked_parents(revs, commit);
2758        }
2759
2760        /*
2761         * A commit simplifies to itself if it is a root, if it is
2762         * UNINTERESTING, if it touches the given paths, or if it is a
2763         * merge and its parents don't simplify to one relevant commit
2764         * (the first two cases are already handled at the beginning of
2765         * this function).
2766         *
2767         * Otherwise, it simplifies to what its sole relevant parent
2768         * simplifies to.
2769         */
2770        if (!cnt ||
2771            (commit->object.flags & UNINTERESTING) ||
2772            !(commit->object.flags & TREESAME) ||
2773            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2774                st->simplified = commit;
2775        else {
2776                pst = locate_simplify_state(revs, parent);
2777                st->simplified = pst->simplified;
2778        }
2779        return tail;
2780}
2781
2782static void simplify_merges(struct rev_info *revs)
2783{
2784        struct commit_list *list, *next;
2785        struct commit_list *yet_to_do, **tail;
2786        struct commit *commit;
2787
2788        if (!revs->prune)
2789                return;
2790
2791        /* feed the list reversed */
2792        yet_to_do = NULL;
2793        for (list = revs->commits; list; list = next) {
2794                commit = list->item;
2795                next = list->next;
2796                /*
2797                 * Do not free(list) here yet; the original list
2798                 * is used later in this function.
2799                 */
2800                commit_list_insert(commit, &yet_to_do);
2801        }
2802        while (yet_to_do) {
2803                list = yet_to_do;
2804                yet_to_do = NULL;
2805                tail = &yet_to_do;
2806                while (list) {
2807                        commit = pop_commit(&list);
2808                        tail = simplify_one(revs, commit, tail);
2809                }
2810        }
2811
2812        /* clean up the result, removing the simplified ones */
2813        list = revs->commits;
2814        revs->commits = NULL;
2815        tail = &revs->commits;
2816        while (list) {
2817                struct merge_simplify_state *st;
2818
2819                commit = pop_commit(&list);
2820                st = locate_simplify_state(revs, commit);
2821                if (st->simplified == commit)
2822                        tail = &commit_list_insert(commit, tail)->next;
2823        }
2824}
2825
2826static void set_children(struct rev_info *revs)
2827{
2828        struct commit_list *l;
2829        for (l = revs->commits; l; l = l->next) {
2830                struct commit *commit = l->item;
2831                struct commit_list *p;
2832
2833                for (p = commit->parents; p; p = p->next)
2834                        add_child(revs, p->item, commit);
2835        }
2836}
2837
2838void reset_revision_walk(void)
2839{
2840        clear_object_flags(SEEN | ADDED | SHOWN);
2841}
2842
2843int prepare_revision_walk(struct rev_info *revs)
2844{
2845        int i;
2846        struct object_array old_pending;
2847        struct commit_list **next = &revs->commits;
2848
2849        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2850        revs->pending.nr = 0;
2851        revs->pending.alloc = 0;
2852        revs->pending.objects = NULL;
2853        for (i = 0; i < old_pending.nr; i++) {
2854                struct object_array_entry *e = old_pending.objects + i;
2855                struct commit *commit = handle_commit(revs, e);
2856                if (commit) {
2857                        if (!(commit->object.flags & SEEN)) {
2858                                commit->object.flags |= SEEN;
2859                                next = commit_list_append(commit, next);
2860                        }
2861                }
2862        }
2863        if (!revs->leak_pending)
2864                object_array_clear(&old_pending);
2865
2866        /* Signal whether we need per-parent treesame decoration */
2867        if (revs->simplify_merges ||
2868            (revs->limited && limiting_can_increase_treesame(revs)))
2869                revs->treesame.name = "treesame";
2870
2871        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2872                commit_list_sort_by_date(&revs->commits);
2873        if (revs->no_walk)
2874                return 0;
2875        if (revs->limited)
2876                if (limit_list(revs) < 0)
2877                        return -1;
2878        if (revs->topo_order)
2879                sort_in_topological_order(&revs->commits, revs->sort_order);
2880        if (revs->line_level_traverse)
2881                line_log_filter(revs);
2882        if (revs->simplify_merges)
2883                simplify_merges(revs);
2884        if (revs->children.name)
2885                set_children(revs);
2886        return 0;
2887}
2888
2889static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2890{
2891        struct commit_list *cache = NULL;
2892
2893        for (;;) {
2894                struct commit *p = *pp;
2895                if (!revs->limited)
2896                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2897                                return rewrite_one_error;
2898                if (p->object.flags & UNINTERESTING)
2899                        return rewrite_one_ok;
2900                if (!(p->object.flags & TREESAME))
2901                        return rewrite_one_ok;
2902                if (!p->parents)
2903                        return rewrite_one_noparents;
2904                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2905                        return rewrite_one_ok;
2906                *pp = p;
2907        }
2908}
2909
2910int rewrite_parents(struct rev_info *revs, struct commit *commit,
2911        rewrite_parent_fn_t rewrite_parent)
2912{
2913        struct commit_list **pp = &commit->parents;
2914        while (*pp) {
2915                struct commit_list *parent = *pp;
2916                switch (rewrite_parent(revs, &parent->item)) {
2917                case rewrite_one_ok:
2918                        break;
2919                case rewrite_one_noparents:
2920                        *pp = parent->next;
2921                        continue;
2922                case rewrite_one_error:
2923                        return -1;
2924                }
2925                pp = &parent->next;
2926        }
2927        remove_duplicate_parents(revs, commit);
2928        return 0;
2929}
2930
2931static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2932{
2933        char *person, *endp;
2934        size_t len, namelen, maillen;
2935        const char *name;
2936        const char *mail;
2937        struct ident_split ident;
2938
2939        person = strstr(buf->buf, what);
2940        if (!person)
2941                return 0;
2942
2943        person += strlen(what);
2944        endp = strchr(person, '\n');
2945        if (!endp)
2946                return 0;
2947
2948        len = endp - person;
2949
2950        if (split_ident_line(&ident, person, len))
2951                return 0;
2952
2953        mail = ident.mail_begin;
2954        maillen = ident.mail_end - ident.mail_begin;
2955        name = ident.name_begin;
2956        namelen = ident.name_end - ident.name_begin;
2957
2958        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2959                struct strbuf namemail = STRBUF_INIT;
2960
2961                strbuf_addf(&namemail, "%.*s <%.*s>",
2962                            (int)namelen, name, (int)maillen, mail);
2963
2964                strbuf_splice(buf, ident.name_begin - buf->buf,
2965                              ident.mail_end - ident.name_begin + 1,
2966                              namemail.buf, namemail.len);
2967
2968                strbuf_release(&namemail);
2969
2970                return 1;
2971        }
2972
2973        return 0;
2974}
2975
2976static int commit_match(struct commit *commit, struct rev_info *opt)
2977{
2978        int retval;
2979        const char *encoding;
2980        const char *message;
2981        struct strbuf buf = STRBUF_INIT;
2982
2983        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2984                return 1;
2985
2986        /* Prepend "fake" headers as needed */
2987        if (opt->grep_filter.use_reflog_filter) {
2988                strbuf_addstr(&buf, "reflog ");
2989                get_reflog_message(&buf, opt->reflog_info);
2990                strbuf_addch(&buf, '\n');
2991        }
2992
2993        /*
2994         * We grep in the user's output encoding, under the assumption that it
2995         * is the encoding they are most likely to write their grep pattern
2996         * for. In addition, it means we will match the "notes" encoding below,
2997         * so we will not end up with a buffer that has two different encodings
2998         * in it.
2999         */
3000        encoding = get_log_output_encoding();
3001        message = logmsg_reencode(commit, NULL, encoding);
3002
3003        /* Copy the commit to temporary if we are using "fake" headers */
3004        if (buf.len)
3005                strbuf_addstr(&buf, message);
3006
3007        if (opt->grep_filter.header_list && opt->mailmap) {
3008                if (!buf.len)
3009                        strbuf_addstr(&buf, message);
3010
3011                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
3012                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
3013        }
3014
3015        /* Append "fake" message parts as needed */
3016        if (opt->show_notes) {
3017                if (!buf.len)
3018                        strbuf_addstr(&buf, message);
3019                format_display_notes(&commit->object.oid, &buf, encoding, 1);
3020        }
3021
3022        /*
3023         * Find either in the original commit message, or in the temporary.
3024         * Note that we cast away the constness of "message" here. It is
3025         * const because it may come from the cached commit buffer. That's OK,
3026         * because we know that it is modifiable heap memory, and that while
3027         * grep_buffer may modify it for speed, it will restore any
3028         * changes before returning.
3029         */
3030        if (buf.len)
3031                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
3032        else
3033                retval = grep_buffer(&opt->grep_filter,
3034                                     (char *)message, strlen(message));
3035        strbuf_release(&buf);
3036        unuse_commit_buffer(commit, message);
3037        return opt->invert_grep ? !retval : retval;
3038}
3039
3040static inline int want_ancestry(const struct rev_info *revs)
3041{
3042        return (revs->rewrite_parents || revs->children.name);
3043}
3044
3045/*
3046 * Return a timestamp to be used for --since/--until comparisons for this
3047 * commit, based on the revision options.
3048 */
3049static timestamp_t comparison_date(const struct rev_info *revs,
3050                                   struct commit *commit)
3051{
3052        return revs->reflog_info ?
3053                get_reflog_timestamp(revs->reflog_info) :
3054                commit->date;
3055}
3056
3057enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
3058{
3059        if (commit->object.flags & SHOWN)
3060                return commit_ignore;
3061        if (revs->unpacked && has_sha1_pack(commit->object.oid.hash))
3062                return commit_ignore;
3063        if (revs->show_all)
3064                return commit_show;
3065        if (commit->object.flags & UNINTERESTING)
3066                return commit_ignore;
3067        if (revs->min_age != -1 &&
3068            comparison_date(revs, commit) > revs->min_age)
3069                        return commit_ignore;
3070        if (revs->min_parents || (revs->max_parents >= 0)) {
3071                int n = commit_list_count(commit->parents);
3072                if ((n < revs->min_parents) ||
3073                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
3074                        return commit_ignore;
3075        }
3076        if (!commit_match(commit, revs))
3077                return commit_ignore;
3078        if (revs->prune && revs->dense) {
3079                /* Commit without changes? */
3080                if (commit->object.flags & TREESAME) {
3081                        int n;
3082                        struct commit_list *p;
3083                        /* drop merges unless we want parenthood */
3084                        if (!want_ancestry(revs))
3085                                return commit_ignore;
3086                        /*
3087                         * If we want ancestry, then need to keep any merges
3088                         * between relevant commits to tie together topology.
3089                         * For consistency with TREESAME and simplification
3090                         * use "relevant" here rather than just INTERESTING,
3091                         * to treat bottom commit(s) as part of the topology.
3092                         */
3093                        for (n = 0, p = commit->parents; p; p = p->next)
3094                                if (relevant_commit(p->item))
3095                                        if (++n >= 2)
3096                                                return commit_show;
3097                        return commit_ignore;
3098                }
3099        }
3100        return commit_show;
3101}
3102
3103define_commit_slab(saved_parents, struct commit_list *);
3104
3105#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
3106
3107/*
3108 * You may only call save_parents() once per commit (this is checked
3109 * for non-root commits).
3110 */
3111static void save_parents(struct rev_info *revs, struct commit *commit)
3112{
3113        struct commit_list **pp;
3114
3115        if (!revs->saved_parents_slab) {
3116                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
3117                init_saved_parents(revs->saved_parents_slab);
3118        }
3119
3120        pp = saved_parents_at(revs->saved_parents_slab, commit);
3121
3122        /*
3123         * When walking with reflogs, we may visit the same commit
3124         * several times: once for each appearance in the reflog.
3125         *
3126         * In this case, save_parents() will be called multiple times.
3127         * We want to keep only the first set of parents.  We need to
3128         * store a sentinel value for an empty (i.e., NULL) parent
3129         * list to distinguish it from a not-yet-saved list, however.
3130         */
3131        if (*pp)
3132                return;
3133        if (commit->parents)
3134                *pp = copy_commit_list(commit->parents);
3135        else
3136                *pp = EMPTY_PARENT_LIST;
3137}
3138
3139static void free_saved_parents(struct rev_info *revs)
3140{
3141        if (revs->saved_parents_slab)
3142                clear_saved_parents(revs->saved_parents_slab);
3143}
3144
3145struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
3146{
3147        struct commit_list *parents;
3148
3149        if (!revs->saved_parents_slab)
3150                return commit->parents;
3151
3152        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3153        if (parents == EMPTY_PARENT_LIST)
3154                return NULL;
3155        return parents;
3156}
3157
3158enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
3159{
3160        enum commit_action action = get_commit_action(revs, commit);
3161
3162        if (action == commit_show &&
3163            !revs->show_all &&
3164            revs->prune && revs->dense && want_ancestry(revs)) {
3165                /*
3166                 * --full-diff on simplified parents is no good: it
3167                 * will show spurious changes from the commits that
3168                 * were elided.  So we save the parents on the side
3169                 * when --full-diff is in effect.
3170                 */
3171                if (revs->full_diff)
3172                        save_parents(revs, commit);
3173                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3174                        return commit_error;
3175        }
3176        return action;
3177}
3178
3179static void track_linear(struct rev_info *revs, struct commit *commit)
3180{
3181        if (revs->track_first_time) {
3182                revs->linear = 1;
3183                revs->track_first_time = 0;
3184        } else {
3185                struct commit_list *p;
3186                for (p = revs->previous_parents; p; p = p->next)
3187                        if (p->item == NULL || /* first commit */
3188                            !oidcmp(&p->item->object.oid, &commit->object.oid))
3189                                break;
3190                revs->linear = p != NULL;
3191        }
3192        if (revs->reverse) {
3193                if (revs->linear)
3194                        commit->object.flags |= TRACK_LINEAR;
3195        }
3196        free_commit_list(revs->previous_parents);
3197        revs->previous_parents = copy_commit_list(commit->parents);
3198}
3199
3200static struct commit *get_revision_1(struct rev_info *revs)
3201{
3202        while (1) {
3203                struct commit *commit;
3204
3205                if (revs->reflog_info)
3206                        commit = next_reflog_entry(revs->reflog_info);
3207                else
3208                        commit = pop_commit(&revs->commits);
3209
3210                if (!commit)
3211                        return NULL;
3212
3213                if (revs->reflog_info)
3214                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3215
3216                /*
3217                 * If we haven't done the list limiting, we need to look at
3218                 * the parents here. We also need to do the date-based limiting
3219                 * that we'd otherwise have done in limit_list().
3220                 */
3221                if (!revs->limited) {
3222                        if (revs->max_age != -1 &&
3223                            comparison_date(revs, commit) < revs->max_age)
3224                                continue;
3225
3226                        if (revs->reflog_info)
3227                                try_to_simplify_commit(revs, commit);
3228                        else if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3229                                if (!revs->ignore_missing_links)
3230                                        die("Failed to traverse parents of commit %s",
3231                                                oid_to_hex(&commit->object.oid));
3232                        }
3233                }
3234
3235                switch (simplify_commit(revs, commit)) {
3236                case commit_ignore:
3237                        continue;
3238                case commit_error:
3239                        die("Failed to simplify parents of commit %s",
3240                            oid_to_hex(&commit->object.oid));
3241                default:
3242                        if (revs->track_linear)
3243                                track_linear(revs, commit);
3244                        return commit;
3245                }
3246        }
3247}
3248
3249/*
3250 * Return true for entries that have not yet been shown.  (This is an
3251 * object_array_each_func_t.)
3252 */
3253static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3254{
3255        return !(entry->item->flags & SHOWN);
3256}
3257
3258/*
3259 * If array is on the verge of a realloc, garbage-collect any entries
3260 * that have already been shown to try to free up some space.
3261 */
3262static void gc_boundary(struct object_array *array)
3263{
3264        if (array->nr == array->alloc)
3265                object_array_filter(array, entry_unshown, NULL);
3266}
3267
3268static void create_boundary_commit_list(struct rev_info *revs)
3269{
3270        unsigned i;
3271        struct commit *c;
3272        struct object_array *array = &revs->boundary_commits;
3273        struct object_array_entry *objects = array->objects;
3274
3275        /*
3276         * If revs->commits is non-NULL at this point, an error occurred in
3277         * get_revision_1().  Ignore the error and continue printing the
3278         * boundary commits anyway.  (This is what the code has always
3279         * done.)
3280         */
3281        if (revs->commits) {
3282                free_commit_list(revs->commits);
3283                revs->commits = NULL;
3284        }
3285
3286        /*
3287         * Put all of the actual boundary commits from revs->boundary_commits
3288         * into revs->commits
3289         */
3290        for (i = 0; i < array->nr; i++) {
3291                c = (struct commit *)(objects[i].item);
3292                if (!c)
3293                        continue;
3294                if (!(c->object.flags & CHILD_SHOWN))
3295                        continue;
3296                if (c->object.flags & (SHOWN | BOUNDARY))
3297                        continue;
3298                c->object.flags |= BOUNDARY;
3299                commit_list_insert(c, &revs->commits);
3300        }
3301
3302        /*
3303         * If revs->topo_order is set, sort the boundary commits
3304         * in topological order
3305         */
3306        sort_in_topological_order(&revs->commits, revs->sort_order);
3307}
3308
3309static struct commit *get_revision_internal(struct rev_info *revs)
3310{
3311        struct commit *c = NULL;
3312        struct commit_list *l;
3313
3314        if (revs->boundary == 2) {
3315                /*
3316                 * All of the normal commits have already been returned,
3317                 * and we are now returning boundary commits.
3318                 * create_boundary_commit_list() has populated
3319                 * revs->commits with the remaining commits to return.
3320                 */
3321                c = pop_commit(&revs->commits);
3322                if (c)
3323                        c->object.flags |= SHOWN;
3324                return c;
3325        }
3326
3327        /*
3328         * If our max_count counter has reached zero, then we are done. We
3329         * don't simply return NULL because we still might need to show
3330         * boundary commits. But we want to avoid calling get_revision_1, which
3331         * might do a considerable amount of work finding the next commit only
3332         * for us to throw it away.
3333         *
3334         * If it is non-zero, then either we don't have a max_count at all
3335         * (-1), or it is still counting, in which case we decrement.
3336         */
3337        if (revs->max_count) {
3338                c = get_revision_1(revs);
3339                if (c) {
3340                        while (revs->skip_count > 0) {
3341                                revs->skip_count--;
3342                                c = get_revision_1(revs);
3343                                if (!c)
3344                                        break;
3345                        }
3346                }
3347
3348                if (revs->max_count > 0)
3349                        revs->max_count--;
3350        }
3351
3352        if (c)
3353                c->object.flags |= SHOWN;
3354
3355        if (!revs->boundary)
3356                return c;
3357
3358        if (!c) {
3359                /*
3360                 * get_revision_1() runs out the commits, and
3361                 * we are done computing the boundaries.
3362                 * switch to boundary commits output mode.
3363                 */
3364                revs->boundary = 2;
3365
3366                /*
3367                 * Update revs->commits to contain the list of
3368                 * boundary commits.
3369                 */
3370                create_boundary_commit_list(revs);
3371
3372                return get_revision_internal(revs);
3373        }
3374
3375        /*
3376         * boundary commits are the commits that are parents of the
3377         * ones we got from get_revision_1() but they themselves are
3378         * not returned from get_revision_1().  Before returning
3379         * 'c', we need to mark its parents that they could be boundaries.
3380         */
3381
3382        for (l = c->parents; l; l = l->next) {
3383                struct object *p;
3384                p = &(l->item->object);
3385                if (p->flags & (CHILD_SHOWN | SHOWN))
3386                        continue;
3387                p->flags |= CHILD_SHOWN;
3388                gc_boundary(&revs->boundary_commits);
3389                add_object_array(p, NULL, &revs->boundary_commits);
3390        }
3391
3392        return c;
3393}
3394
3395struct commit *get_revision(struct rev_info *revs)
3396{
3397        struct commit *c;
3398        struct commit_list *reversed;
3399
3400        if (revs->reverse) {
3401                reversed = NULL;
3402                while ((c = get_revision_internal(revs)))
3403                        commit_list_insert(c, &reversed);
3404                revs->commits = reversed;
3405                revs->reverse = 0;
3406                revs->reverse_output_stage = 1;
3407        }
3408
3409        if (revs->reverse_output_stage) {
3410                c = pop_commit(&revs->commits);
3411                if (revs->track_linear)
3412                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3413                return c;
3414        }
3415
3416        c = get_revision_internal(revs);
3417        if (c && revs->graph)
3418                graph_update(revs->graph, c);
3419        if (!c) {
3420                free_saved_parents(revs);
3421                if (revs->previous_parents) {
3422                        free_commit_list(revs->previous_parents);
3423                        revs->previous_parents = NULL;
3424                }
3425        }
3426        return c;
3427}
3428
3429char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3430{
3431        if (commit->object.flags & BOUNDARY)
3432                return "-";
3433        else if (commit->object.flags & UNINTERESTING)
3434                return "^";
3435        else if (commit->object.flags & PATCHSAME)
3436                return "=";
3437        else if (!revs || revs->left_right) {
3438                if (commit->object.flags & SYMMETRIC_LEFT)
3439                        return "<";
3440                else
3441                        return ">";
3442        } else if (revs->graph)
3443                return "*";
3444        else if (revs->cherry_mark)
3445                return "+";
3446        return "";
3447}
3448
3449void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3450{
3451        char *mark = get_revision_mark(revs, commit);
3452        if (!strlen(mark))
3453                return;
3454        fputs(mark, stdout);
3455        putchar(' ');
3456}