revision.con commit Merge branch 'tz/fsf-address-update' of ../git-gui into tz/fsf-address-update (5313bee)
   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 * That means that once we get to REV_TREE_DIFFERENT, we do not
 399 * have to look any further.
 400 */
 401static int tree_difference = REV_TREE_SAME;
 402
 403static void file_add_remove(struct diff_options *options,
 404                    int addremove, unsigned mode,
 405                    const struct object_id *oid,
 406                    int oid_valid,
 407                    const char *fullpath, unsigned dirty_submodule)
 408{
 409        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 410
 411        tree_difference |= diff;
 412        if (tree_difference == REV_TREE_DIFFERENT)
 413                DIFF_OPT_SET(options, HAS_CHANGES);
 414}
 415
 416static void file_change(struct diff_options *options,
 417                 unsigned old_mode, unsigned new_mode,
 418                 const struct object_id *old_oid,
 419                 const struct object_id *new_oid,
 420                 int old_oid_valid, int new_oid_valid,
 421                 const char *fullpath,
 422                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 423{
 424        tree_difference = REV_TREE_DIFFERENT;
 425        DIFF_OPT_SET(options, HAS_CHANGES);
 426}
 427
 428static int rev_compare_tree(struct rev_info *revs,
 429                            struct commit *parent, struct commit *commit)
 430{
 431        struct tree *t1 = parent->tree;
 432        struct tree *t2 = commit->tree;
 433
 434        if (!t1)
 435                return REV_TREE_NEW;
 436        if (!t2)
 437                return REV_TREE_OLD;
 438
 439        if (revs->simplify_by_decoration) {
 440                /*
 441                 * If we are simplifying by decoration, then the commit
 442                 * is worth showing if it has a tag pointing at it.
 443                 */
 444                if (get_name_decoration(&commit->object))
 445                        return REV_TREE_DIFFERENT;
 446                /*
 447                 * A commit that is not pointed by a tag is uninteresting
 448                 * if we are not limited by path.  This means that you will
 449                 * see the usual "commits that touch the paths" plus any
 450                 * tagged commit by specifying both --simplify-by-decoration
 451                 * and pathspec.
 452                 */
 453                if (!revs->prune_data.nr)
 454                        return REV_TREE_SAME;
 455        }
 456
 457        tree_difference = REV_TREE_SAME;
 458        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 459        if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
 460                           &revs->pruning) < 0)
 461                return REV_TREE_DIFFERENT;
 462        return tree_difference;
 463}
 464
 465static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 466{
 467        int retval;
 468        struct tree *t1 = commit->tree;
 469
 470        if (!t1)
 471                return 0;
 472
 473        tree_difference = REV_TREE_SAME;
 474        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 475        retval = diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);
 476
 477        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 478}
 479
 480struct treesame_state {
 481        unsigned int nparents;
 482        unsigned char treesame[FLEX_ARRAY];
 483};
 484
 485static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 486{
 487        unsigned n = commit_list_count(commit->parents);
 488        struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 489        st->nparents = n;
 490        add_decoration(&revs->treesame, &commit->object, st);
 491        return st;
 492}
 493
 494/*
 495 * Must be called immediately after removing the nth_parent from a commit's
 496 * parent list, if we are maintaining the per-parent treesame[] decoration.
 497 * This does not recalculate the master TREESAME flag - update_treesame()
 498 * should be called to update it after a sequence of treesame[] modifications
 499 * that may have affected it.
 500 */
 501static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 502{
 503        struct treesame_state *st;
 504        int old_same;
 505
 506        if (!commit->parents) {
 507                /*
 508                 * Have just removed the only parent from a non-merge.
 509                 * Different handling, as we lack decoration.
 510                 */
 511                if (nth_parent != 0)
 512                        die("compact_treesame %u", nth_parent);
 513                old_same = !!(commit->object.flags & TREESAME);
 514                if (rev_same_tree_as_empty(revs, commit))
 515                        commit->object.flags |= TREESAME;
 516                else
 517                        commit->object.flags &= ~TREESAME;
 518                return old_same;
 519        }
 520
 521        st = lookup_decoration(&revs->treesame, &commit->object);
 522        if (!st || nth_parent >= st->nparents)
 523                die("compact_treesame %u", nth_parent);
 524
 525        old_same = st->treesame[nth_parent];
 526        memmove(st->treesame + nth_parent,
 527                st->treesame + nth_parent + 1,
 528                st->nparents - nth_parent - 1);
 529
 530        /*
 531         * If we've just become a non-merge commit, update TREESAME
 532         * immediately, and remove the no-longer-needed decoration.
 533         * If still a merge, defer update until update_treesame().
 534         */
 535        if (--st->nparents == 1) {
 536                if (commit->parents->next)
 537                        die("compact_treesame parents mismatch");
 538                if (st->treesame[0] && revs->dense)
 539                        commit->object.flags |= TREESAME;
 540                else
 541                        commit->object.flags &= ~TREESAME;
 542                free(add_decoration(&revs->treesame, &commit->object, NULL));
 543        }
 544
 545        return old_same;
 546}
 547
 548static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 549{
 550        if (commit->parents && commit->parents->next) {
 551                unsigned n;
 552                struct treesame_state *st;
 553                struct commit_list *p;
 554                unsigned relevant_parents;
 555                unsigned relevant_change, irrelevant_change;
 556
 557                st = lookup_decoration(&revs->treesame, &commit->object);
 558                if (!st)
 559                        die("update_treesame %s", oid_to_hex(&commit->object.oid));
 560                relevant_parents = 0;
 561                relevant_change = irrelevant_change = 0;
 562                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 563                        if (relevant_commit(p->item)) {
 564                                relevant_change |= !st->treesame[n];
 565                                relevant_parents++;
 566                        } else
 567                                irrelevant_change |= !st->treesame[n];
 568                }
 569                if (relevant_parents ? relevant_change : irrelevant_change)
 570                        commit->object.flags &= ~TREESAME;
 571                else
 572                        commit->object.flags |= TREESAME;
 573        }
 574
 575        return commit->object.flags & TREESAME;
 576}
 577
 578static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 579{
 580        /*
 581         * TREESAME is irrelevant unless prune && dense;
 582         * if simplify_history is set, we can't have a mixture of TREESAME and
 583         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 584         *    decoration anyway);
 585         * if first_parent_only is set, then the TREESAME flag is locked
 586         *    against the first parent (and again we lack treesame[] decoration).
 587         */
 588        return revs->prune && revs->dense &&
 589               !revs->simplify_history &&
 590               !revs->first_parent_only;
 591}
 592
 593static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 594{
 595        struct commit_list **pp, *parent;
 596        struct treesame_state *ts = NULL;
 597        int relevant_change = 0, irrelevant_change = 0;
 598        int relevant_parents, nth_parent;
 599
 600        /*
 601         * If we don't do pruning, everything is interesting
 602         */
 603        if (!revs->prune)
 604                return;
 605
 606        if (!commit->tree)
 607                return;
 608
 609        if (!commit->parents) {
 610                if (rev_same_tree_as_empty(revs, commit))
 611                        commit->object.flags |= TREESAME;
 612                return;
 613        }
 614
 615        /*
 616         * Normal non-merge commit? If we don't want to make the
 617         * history dense, we consider it always to be a change..
 618         */
 619        if (!revs->dense && !commit->parents->next)
 620                return;
 621
 622        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 623             (parent = *pp) != NULL;
 624             pp = &parent->next, nth_parent++) {
 625                struct commit *p = parent->item;
 626                if (relevant_commit(p))
 627                        relevant_parents++;
 628
 629                if (nth_parent == 1) {
 630                        /*
 631                         * This our second loop iteration - so we now know
 632                         * we're dealing with a merge.
 633                         *
 634                         * Do not compare with later parents when we care only about
 635                         * the first parent chain, in order to avoid derailing the
 636                         * traversal to follow a side branch that brought everything
 637                         * in the path we are limited to by the pathspec.
 638                         */
 639                        if (revs->first_parent_only)
 640                                break;
 641                        /*
 642                         * If this will remain a potentially-simplifiable
 643                         * merge, remember per-parent treesame if needed.
 644                         * Initialise the array with the comparison from our
 645                         * first iteration.
 646                         */
 647                        if (revs->treesame.name &&
 648                            !revs->simplify_history &&
 649                            !(commit->object.flags & UNINTERESTING)) {
 650                                ts = initialise_treesame(revs, commit);
 651                                if (!(irrelevant_change || relevant_change))
 652                                        ts->treesame[0] = 1;
 653                        }
 654                }
 655                if (parse_commit(p) < 0)
 656                        die("cannot simplify commit %s (because of %s)",
 657                            oid_to_hex(&commit->object.oid),
 658                            oid_to_hex(&p->object.oid));
 659                switch (rev_compare_tree(revs, p, commit)) {
 660                case REV_TREE_SAME:
 661                        if (!revs->simplify_history || !relevant_commit(p)) {
 662                                /* Even if a merge with an uninteresting
 663                                 * side branch brought the entire change
 664                                 * we are interested in, we do not want
 665                                 * to lose the other branches of this
 666                                 * merge, so we just keep going.
 667                                 */
 668                                if (ts)
 669                                        ts->treesame[nth_parent] = 1;
 670                                continue;
 671                        }
 672                        parent->next = NULL;
 673                        commit->parents = parent;
 674                        commit->object.flags |= TREESAME;
 675                        return;
 676
 677                case REV_TREE_NEW:
 678                        if (revs->remove_empty_trees &&
 679                            rev_same_tree_as_empty(revs, p)) {
 680                                /* We are adding all the specified
 681                                 * paths from this parent, so the
 682                                 * history beyond this parent is not
 683                                 * interesting.  Remove its parents
 684                                 * (they are grandparents for us).
 685                                 * IOW, we pretend this parent is a
 686                                 * "root" commit.
 687                                 */
 688                                if (parse_commit(p) < 0)
 689                                        die("cannot simplify commit %s (invalid %s)",
 690                                            oid_to_hex(&commit->object.oid),
 691                                            oid_to_hex(&p->object.oid));
 692                                p->parents = NULL;
 693                        }
 694                /* fallthrough */
 695                case REV_TREE_OLD:
 696                case REV_TREE_DIFFERENT:
 697                        if (relevant_commit(p))
 698                                relevant_change = 1;
 699                        else
 700                                irrelevant_change = 1;
 701                        continue;
 702                }
 703                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
 704        }
 705
 706        /*
 707         * TREESAME is straightforward for single-parent commits. For merge
 708         * commits, it is most useful to define it so that "irrelevant"
 709         * parents cannot make us !TREESAME - if we have any relevant
 710         * parents, then we only consider TREESAMEness with respect to them,
 711         * allowing irrelevant merges from uninteresting branches to be
 712         * simplified away. Only if we have only irrelevant parents do we
 713         * base TREESAME on them. Note that this logic is replicated in
 714         * update_treesame, which should be kept in sync.
 715         */
 716        if (relevant_parents ? !relevant_change : !irrelevant_change)
 717                commit->object.flags |= TREESAME;
 718}
 719
 720static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 721                    struct commit_list *cached_base, struct commit_list **cache)
 722{
 723        struct commit_list *new_entry;
 724
 725        if (cached_base && p->date < cached_base->item->date)
 726                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 727        else
 728                new_entry = commit_list_insert_by_date(p, head);
 729
 730        if (cache && (!*cache || p->date < (*cache)->item->date))
 731                *cache = new_entry;
 732}
 733
 734static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 735                    struct commit_list **list, struct commit_list **cache_ptr)
 736{
 737        struct commit_list *parent = commit->parents;
 738        unsigned left_flag;
 739        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 740
 741        if (commit->object.flags & ADDED)
 742                return 0;
 743        commit->object.flags |= ADDED;
 744
 745        if (revs->include_check &&
 746            !revs->include_check(commit, revs->include_check_data))
 747                return 0;
 748
 749        /*
 750         * If the commit is uninteresting, don't try to
 751         * prune parents - we want the maximal uninteresting
 752         * set.
 753         *
 754         * Normally we haven't parsed the parent
 755         * yet, so we won't have a parent of a parent
 756         * here. However, it may turn out that we've
 757         * reached this commit some other way (where it
 758         * wasn't uninteresting), in which case we need
 759         * to mark its parents recursively too..
 760         */
 761        if (commit->object.flags & UNINTERESTING) {
 762                while (parent) {
 763                        struct commit *p = parent->item;
 764                        parent = parent->next;
 765                        if (p)
 766                                p->object.flags |= UNINTERESTING;
 767                        if (parse_commit_gently(p, 1) < 0)
 768                                continue;
 769                        if (p->parents)
 770                                mark_parents_uninteresting(p);
 771                        if (p->object.flags & SEEN)
 772                                continue;
 773                        p->object.flags |= SEEN;
 774                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 775                }
 776                return 0;
 777        }
 778
 779        /*
 780         * Ok, the commit wasn't uninteresting. Try to
 781         * simplify the commit history and find the parent
 782         * that has no differences in the path set if one exists.
 783         */
 784        try_to_simplify_commit(revs, commit);
 785
 786        if (revs->no_walk)
 787                return 0;
 788
 789        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 790
 791        for (parent = commit->parents; parent; parent = parent->next) {
 792                struct commit *p = parent->item;
 793
 794                if (parse_commit_gently(p, revs->ignore_missing_links) < 0)
 795                        return -1;
 796                if (revs->show_source && !p->util)
 797                        p->util = commit->util;
 798                p->object.flags |= left_flag;
 799                if (!(p->object.flags & SEEN)) {
 800                        p->object.flags |= SEEN;
 801                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 802                }
 803                if (revs->first_parent_only)
 804                        break;
 805        }
 806        return 0;
 807}
 808
 809static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 810{
 811        struct commit_list *p;
 812        int left_count = 0, right_count = 0;
 813        int left_first;
 814        struct patch_ids ids;
 815        unsigned cherry_flag;
 816
 817        /* First count the commits on the left and on the right */
 818        for (p = list; p; p = p->next) {
 819                struct commit *commit = p->item;
 820                unsigned flags = commit->object.flags;
 821                if (flags & BOUNDARY)
 822                        ;
 823                else if (flags & SYMMETRIC_LEFT)
 824                        left_count++;
 825                else
 826                        right_count++;
 827        }
 828
 829        if (!left_count || !right_count)
 830                return;
 831
 832        left_first = left_count < right_count;
 833        init_patch_ids(&ids);
 834        ids.diffopts.pathspec = revs->diffopt.pathspec;
 835
 836        /* Compute patch-ids for one side */
 837        for (p = list; p; p = p->next) {
 838                struct commit *commit = p->item;
 839                unsigned flags = commit->object.flags;
 840
 841                if (flags & BOUNDARY)
 842                        continue;
 843                /*
 844                 * If we have fewer left, left_first is set and we omit
 845                 * commits on the right branch in this loop.  If we have
 846                 * fewer right, we skip the left ones.
 847                 */
 848                if (left_first != !!(flags & SYMMETRIC_LEFT))
 849                        continue;
 850                add_commit_patch_id(commit, &ids);
 851        }
 852
 853        /* either cherry_mark or cherry_pick are true */
 854        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 855
 856        /* Check the other side */
 857        for (p = list; p; p = p->next) {
 858                struct commit *commit = p->item;
 859                struct patch_id *id;
 860                unsigned flags = commit->object.flags;
 861
 862                if (flags & BOUNDARY)
 863                        continue;
 864                /*
 865                 * If we have fewer left, left_first is set and we omit
 866                 * commits on the left branch in this loop.
 867                 */
 868                if (left_first == !!(flags & SYMMETRIC_LEFT))
 869                        continue;
 870
 871                /*
 872                 * Have we seen the same patch id?
 873                 */
 874                id = has_commit_patch_id(commit, &ids);
 875                if (!id)
 876                        continue;
 877
 878                commit->object.flags |= cherry_flag;
 879                id->commit->object.flags |= cherry_flag;
 880        }
 881
 882        free_patch_ids(&ids);
 883}
 884
 885/* How many extra uninteresting commits we want to see.. */
 886#define SLOP 5
 887
 888static int still_interesting(struct commit_list *src, timestamp_t date, int slop,
 889                             struct commit **interesting_cache)
 890{
 891        /*
 892         * No source list at all? We're definitely done..
 893         */
 894        if (!src)
 895                return 0;
 896
 897        /*
 898         * Does the destination list contain entries with a date
 899         * before the source list? Definitely _not_ done.
 900         */
 901        if (date <= src->item->date)
 902                return SLOP;
 903
 904        /*
 905         * Does the source list still have interesting commits in
 906         * it? Definitely not done..
 907         */
 908        if (!everybody_uninteresting(src, interesting_cache))
 909                return SLOP;
 910
 911        /* Ok, we're closing in.. */
 912        return slop-1;
 913}
 914
 915/*
 916 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 917 * of B but not ancestors of A but further limits the result to those
 918 * that are descendants of A.  This takes the list of bottom commits and
 919 * the result of "A..B" without --ancestry-path, and limits the latter
 920 * further to the ones that can reach one of the commits in "bottom".
 921 */
 922static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 923{
 924        struct commit_list *p;
 925        struct commit_list *rlist = NULL;
 926        int made_progress;
 927
 928        /*
 929         * Reverse the list so that it will be likely that we would
 930         * process parents before children.
 931         */
 932        for (p = list; p; p = p->next)
 933                commit_list_insert(p->item, &rlist);
 934
 935        for (p = bottom; p; p = p->next)
 936                p->item->object.flags |= TMP_MARK;
 937
 938        /*
 939         * Mark the ones that can reach bottom commits in "list",
 940         * in a bottom-up fashion.
 941         */
 942        do {
 943                made_progress = 0;
 944                for (p = rlist; p; p = p->next) {
 945                        struct commit *c = p->item;
 946                        struct commit_list *parents;
 947                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 948                                continue;
 949                        for (parents = c->parents;
 950                             parents;
 951                             parents = parents->next) {
 952                                if (!(parents->item->object.flags & TMP_MARK))
 953                                        continue;
 954                                c->object.flags |= TMP_MARK;
 955                                made_progress = 1;
 956                                break;
 957                        }
 958                }
 959        } while (made_progress);
 960
 961        /*
 962         * NEEDSWORK: decide if we want to remove parents that are
 963         * not marked with TMP_MARK from commit->parents for commits
 964         * in the resulting list.  We may not want to do that, though.
 965         */
 966
 967        /*
 968         * The ones that are not marked with TMP_MARK are uninteresting
 969         */
 970        for (p = list; p; p = p->next) {
 971                struct commit *c = p->item;
 972                if (c->object.flags & TMP_MARK)
 973                        continue;
 974                c->object.flags |= UNINTERESTING;
 975        }
 976
 977        /* We are done with the TMP_MARK */
 978        for (p = list; p; p = p->next)
 979                p->item->object.flags &= ~TMP_MARK;
 980        for (p = bottom; p; p = p->next)
 981                p->item->object.flags &= ~TMP_MARK;
 982        free_commit_list(rlist);
 983}
 984
 985/*
 986 * Before walking the history, keep the set of "negative" refs the
 987 * caller has asked to exclude.
 988 *
 989 * This is used to compute "rev-list --ancestry-path A..B", as we need
 990 * to filter the result of "A..B" further to the ones that can actually
 991 * reach A.
 992 */
 993static struct commit_list *collect_bottom_commits(struct commit_list *list)
 994{
 995        struct commit_list *elem, *bottom = NULL;
 996        for (elem = list; elem; elem = elem->next)
 997                if (elem->item->object.flags & BOTTOM)
 998                        commit_list_insert(elem->item, &bottom);
 999        return bottom;
1000}
1001
1002/* Assumes either left_only or right_only is set */
1003static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1004{
1005        struct commit_list *p;
1006
1007        for (p = list; p; p = p->next) {
1008                struct commit *commit = p->item;
1009
1010                if (revs->right_only) {
1011                        if (commit->object.flags & SYMMETRIC_LEFT)
1012                                commit->object.flags |= SHOWN;
1013                } else  /* revs->left_only is set */
1014                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1015                                commit->object.flags |= SHOWN;
1016        }
1017}
1018
1019static int limit_list(struct rev_info *revs)
1020{
1021        int slop = SLOP;
1022        timestamp_t date = TIME_MAX;
1023        struct commit_list *list = revs->commits;
1024        struct commit_list *newlist = NULL;
1025        struct commit_list **p = &newlist;
1026        struct commit_list *bottom = NULL;
1027        struct commit *interesting_cache = NULL;
1028
1029        if (revs->ancestry_path) {
1030                bottom = collect_bottom_commits(list);
1031                if (!bottom)
1032                        die("--ancestry-path given but there are no bottom commits");
1033        }
1034
1035        while (list) {
1036                struct commit *commit = pop_commit(&list);
1037                struct object *obj = &commit->object;
1038                show_early_output_fn_t show;
1039
1040                if (commit == interesting_cache)
1041                        interesting_cache = NULL;
1042
1043                if (revs->max_age != -1 && (commit->date < revs->max_age))
1044                        obj->flags |= UNINTERESTING;
1045                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1046                        return -1;
1047                if (obj->flags & UNINTERESTING) {
1048                        mark_parents_uninteresting(commit);
1049                        if (revs->show_all)
1050                                p = &commit_list_insert(commit, p)->next;
1051                        slop = still_interesting(list, date, slop, &interesting_cache);
1052                        if (slop)
1053                                continue;
1054                        /* If showing all, add the whole pending list to the end */
1055                        if (revs->show_all)
1056                                *p = list;
1057                        break;
1058                }
1059                if (revs->min_age != -1 && (commit->date > revs->min_age))
1060                        continue;
1061                date = commit->date;
1062                p = &commit_list_insert(commit, p)->next;
1063
1064                show = show_early_output;
1065                if (!show)
1066                        continue;
1067
1068                show(revs, newlist);
1069                show_early_output = NULL;
1070        }
1071        if (revs->cherry_pick || revs->cherry_mark)
1072                cherry_pick_list(newlist, revs);
1073
1074        if (revs->left_only || revs->right_only)
1075                limit_left_right(newlist, revs);
1076
1077        if (bottom) {
1078                limit_to_ancestry(bottom, newlist);
1079                free_commit_list(bottom);
1080        }
1081
1082        /*
1083         * Check if any commits have become TREESAME by some of their parents
1084         * becoming UNINTERESTING.
1085         */
1086        if (limiting_can_increase_treesame(revs))
1087                for (list = newlist; list; list = list->next) {
1088                        struct commit *c = list->item;
1089                        if (c->object.flags & (UNINTERESTING | TREESAME))
1090                                continue;
1091                        update_treesame(revs, c);
1092                }
1093
1094        revs->commits = newlist;
1095        return 0;
1096}
1097
1098/*
1099 * Add an entry to refs->cmdline with the specified information.
1100 * *name is copied.
1101 */
1102static void add_rev_cmdline(struct rev_info *revs,
1103                            struct object *item,
1104                            const char *name,
1105                            int whence,
1106                            unsigned flags)
1107{
1108        struct rev_cmdline_info *info = &revs->cmdline;
1109        unsigned int nr = info->nr;
1110
1111        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1112        info->rev[nr].item = item;
1113        info->rev[nr].name = xstrdup(name);
1114        info->rev[nr].whence = whence;
1115        info->rev[nr].flags = flags;
1116        info->nr++;
1117}
1118
1119static void add_rev_cmdline_list(struct rev_info *revs,
1120                                 struct commit_list *commit_list,
1121                                 int whence,
1122                                 unsigned flags)
1123{
1124        while (commit_list) {
1125                struct object *object = &commit_list->item->object;
1126                add_rev_cmdline(revs, object, oid_to_hex(&object->oid),
1127                                whence, flags);
1128                commit_list = commit_list->next;
1129        }
1130}
1131
1132struct all_refs_cb {
1133        int all_flags;
1134        int warned_bad_reflog;
1135        struct rev_info *all_revs;
1136        const char *name_for_errormsg;
1137        struct ref_store *refs;
1138};
1139
1140int ref_excluded(struct string_list *ref_excludes, const char *path)
1141{
1142        struct string_list_item *item;
1143
1144        if (!ref_excludes)
1145                return 0;
1146        for_each_string_list_item(item, ref_excludes) {
1147                if (!wildmatch(item->string, path, 0))
1148                        return 1;
1149        }
1150        return 0;
1151}
1152
1153static int handle_one_ref(const char *path, const struct object_id *oid,
1154                          int flag, void *cb_data)
1155{
1156        struct all_refs_cb *cb = cb_data;
1157        struct object *object;
1158
1159        if (ref_excluded(cb->all_revs->ref_excludes, path))
1160            return 0;
1161
1162        object = get_reference(cb->all_revs, path, oid, cb->all_flags);
1163        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1164        add_pending_oid(cb->all_revs, path, oid, cb->all_flags);
1165        return 0;
1166}
1167
1168static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1169        unsigned flags)
1170{
1171        cb->all_revs = revs;
1172        cb->all_flags = flags;
1173        revs->rev_input_given = 1;
1174        cb->refs = NULL;
1175}
1176
1177void clear_ref_exclusion(struct string_list **ref_excludes_p)
1178{
1179        if (*ref_excludes_p) {
1180                string_list_clear(*ref_excludes_p, 0);
1181                free(*ref_excludes_p);
1182        }
1183        *ref_excludes_p = NULL;
1184}
1185
1186void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1187{
1188        if (!*ref_excludes_p) {
1189                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1190                (*ref_excludes_p)->strdup_strings = 1;
1191        }
1192        string_list_append(*ref_excludes_p, exclude);
1193}
1194
1195static void handle_refs(struct ref_store *refs,
1196                        struct rev_info *revs, unsigned flags,
1197                        int (*for_each)(struct ref_store *, each_ref_fn, void *))
1198{
1199        struct all_refs_cb cb;
1200
1201        if (!refs) {
1202                /* this could happen with uninitialized submodules */
1203                return;
1204        }
1205
1206        init_all_refs_cb(&cb, revs, flags);
1207        for_each(refs, handle_one_ref, &cb);
1208}
1209
1210static void handle_one_reflog_commit(struct object_id *oid, void *cb_data)
1211{
1212        struct all_refs_cb *cb = cb_data;
1213        if (!is_null_oid(oid)) {
1214                struct object *o = parse_object(oid);
1215                if (o) {
1216                        o->flags |= cb->all_flags;
1217                        /* ??? CMDLINEFLAGS ??? */
1218                        add_pending_object(cb->all_revs, o, "");
1219                }
1220                else if (!cb->warned_bad_reflog) {
1221                        warning("reflog of '%s' references pruned commits",
1222                                cb->name_for_errormsg);
1223                        cb->warned_bad_reflog = 1;
1224                }
1225        }
1226}
1227
1228static int handle_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
1229                const char *email, timestamp_t timestamp, int tz,
1230                const char *message, void *cb_data)
1231{
1232        handle_one_reflog_commit(ooid, cb_data);
1233        handle_one_reflog_commit(noid, cb_data);
1234        return 0;
1235}
1236
1237static int handle_one_reflog(const char *path, const struct object_id *oid,
1238                             int flag, void *cb_data)
1239{
1240        struct all_refs_cb *cb = cb_data;
1241        cb->warned_bad_reflog = 0;
1242        cb->name_for_errormsg = path;
1243        refs_for_each_reflog_ent(cb->refs, path,
1244                                 handle_one_reflog_ent, cb_data);
1245        return 0;
1246}
1247
1248static void add_other_reflogs_to_pending(struct all_refs_cb *cb)
1249{
1250        struct worktree **worktrees, **p;
1251
1252        worktrees = get_worktrees(0);
1253        for (p = worktrees; *p; p++) {
1254                struct worktree *wt = *p;
1255
1256                if (wt->is_current)
1257                        continue;
1258
1259                cb->refs = get_worktree_ref_store(wt);
1260                refs_for_each_reflog(cb->refs,
1261                                     handle_one_reflog,
1262                                     cb);
1263        }
1264        free_worktrees(worktrees);
1265}
1266
1267void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1268{
1269        struct all_refs_cb cb;
1270
1271        cb.all_revs = revs;
1272        cb.all_flags = flags;
1273        cb.refs = get_main_ref_store();
1274        for_each_reflog(handle_one_reflog, &cb);
1275
1276        if (!revs->single_worktree)
1277                add_other_reflogs_to_pending(&cb);
1278}
1279
1280static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1281                           struct strbuf *path)
1282{
1283        size_t baselen = path->len;
1284        int i;
1285
1286        if (it->entry_count >= 0) {
1287                struct tree *tree = lookup_tree(&it->oid);
1288                add_pending_object_with_path(revs, &tree->object, "",
1289                                             040000, path->buf);
1290        }
1291
1292        for (i = 0; i < it->subtree_nr; i++) {
1293                struct cache_tree_sub *sub = it->down[i];
1294                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1295                add_cache_tree(sub->cache_tree, revs, path);
1296                strbuf_setlen(path, baselen);
1297        }
1298
1299}
1300
1301static void do_add_index_objects_to_pending(struct rev_info *revs,
1302                                            struct index_state *istate)
1303{
1304        int i;
1305
1306        for (i = 0; i < istate->cache_nr; i++) {
1307                struct cache_entry *ce = istate->cache[i];
1308                struct blob *blob;
1309
1310                if (S_ISGITLINK(ce->ce_mode))
1311                        continue;
1312
1313                blob = lookup_blob(&ce->oid);
1314                if (!blob)
1315                        die("unable to add index blob to traversal");
1316                add_pending_object_with_path(revs, &blob->object, "",
1317                                             ce->ce_mode, ce->name);
1318        }
1319
1320        if (istate->cache_tree) {
1321                struct strbuf path = STRBUF_INIT;
1322                add_cache_tree(istate->cache_tree, revs, &path);
1323                strbuf_release(&path);
1324        }
1325}
1326
1327void add_index_objects_to_pending(struct rev_info *revs, unsigned int flags)
1328{
1329        struct worktree **worktrees, **p;
1330
1331        read_cache();
1332        do_add_index_objects_to_pending(revs, &the_index);
1333
1334        if (revs->single_worktree)
1335                return;
1336
1337        worktrees = get_worktrees(0);
1338        for (p = worktrees; *p; p++) {
1339                struct worktree *wt = *p;
1340                struct index_state istate = { NULL };
1341
1342                if (wt->is_current)
1343                        continue; /* current index already taken care of */
1344
1345                if (read_index_from(&istate,
1346                                    worktree_git_path(wt, "index")) > 0)
1347                        do_add_index_objects_to_pending(revs, &istate);
1348                discard_index(&istate);
1349        }
1350        free_worktrees(worktrees);
1351}
1352
1353static int add_parents_only(struct rev_info *revs, const char *arg_, int flags,
1354                            int exclude_parent)
1355{
1356        struct object_id oid;
1357        struct object *it;
1358        struct commit *commit;
1359        struct commit_list *parents;
1360        int parent_number;
1361        const char *arg = arg_;
1362
1363        if (*arg == '^') {
1364                flags ^= UNINTERESTING | BOTTOM;
1365                arg++;
1366        }
1367        if (get_oid_committish(arg, &oid))
1368                return 0;
1369        while (1) {
1370                it = get_reference(revs, arg, &oid, 0);
1371                if (!it && revs->ignore_missing)
1372                        return 0;
1373                if (it->type != OBJ_TAG)
1374                        break;
1375                if (!((struct tag*)it)->tagged)
1376                        return 0;
1377                oidcpy(&oid, &((struct tag*)it)->tagged->oid);
1378        }
1379        if (it->type != OBJ_COMMIT)
1380                return 0;
1381        commit = (struct commit *)it;
1382        if (exclude_parent &&
1383            exclude_parent > commit_list_count(commit->parents))
1384                return 0;
1385        for (parents = commit->parents, parent_number = 1;
1386             parents;
1387             parents = parents->next, parent_number++) {
1388                if (exclude_parent && parent_number != exclude_parent)
1389                        continue;
1390
1391                it = &parents->item->object;
1392                it->flags |= flags;
1393                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1394                add_pending_object(revs, it, arg);
1395        }
1396        return 1;
1397}
1398
1399void init_revisions(struct rev_info *revs, const char *prefix)
1400{
1401        memset(revs, 0, sizeof(*revs));
1402
1403        revs->abbrev = DEFAULT_ABBREV;
1404        revs->ignore_merges = 1;
1405        revs->simplify_history = 1;
1406        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
1407        DIFF_OPT_SET(&revs->pruning, QUICK);
1408        revs->pruning.add_remove = file_add_remove;
1409        revs->pruning.change = file_change;
1410        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1411        revs->dense = 1;
1412        revs->prefix = prefix;
1413        revs->max_age = -1;
1414        revs->min_age = -1;
1415        revs->skip_count = -1;
1416        revs->max_count = -1;
1417        revs->max_parents = -1;
1418        revs->expand_tabs_in_log = -1;
1419
1420        revs->commit_format = CMIT_FMT_DEFAULT;
1421        revs->expand_tabs_in_log_default = 8;
1422
1423        init_grep_defaults();
1424        grep_init(&revs->grep_filter, prefix);
1425        revs->grep_filter.status_only = 1;
1426
1427        diff_setup(&revs->diffopt);
1428        if (prefix && !revs->diffopt.prefix) {
1429                revs->diffopt.prefix = prefix;
1430                revs->diffopt.prefix_length = strlen(prefix);
1431        }
1432
1433        revs->notes_opt.use_default_notes = -1;
1434}
1435
1436static void add_pending_commit_list(struct rev_info *revs,
1437                                    struct commit_list *commit_list,
1438                                    unsigned int flags)
1439{
1440        while (commit_list) {
1441                struct object *object = &commit_list->item->object;
1442                object->flags |= flags;
1443                add_pending_object(revs, object, oid_to_hex(&object->oid));
1444                commit_list = commit_list->next;
1445        }
1446}
1447
1448static void prepare_show_merge(struct rev_info *revs)
1449{
1450        struct commit_list *bases;
1451        struct commit *head, *other;
1452        struct object_id oid;
1453        const char **prune = NULL;
1454        int i, prune_num = 1; /* counting terminating NULL */
1455
1456        if (get_oid("HEAD", &oid))
1457                die("--merge without HEAD?");
1458        head = lookup_commit_or_die(&oid, "HEAD");
1459        if (get_oid("MERGE_HEAD", &oid))
1460                die("--merge without MERGE_HEAD?");
1461        other = lookup_commit_or_die(&oid, "MERGE_HEAD");
1462        add_pending_object(revs, &head->object, "HEAD");
1463        add_pending_object(revs, &other->object, "MERGE_HEAD");
1464        bases = get_merge_bases(head, other);
1465        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1466        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1467        free_commit_list(bases);
1468        head->object.flags |= SYMMETRIC_LEFT;
1469
1470        if (!active_nr)
1471                read_cache();
1472        for (i = 0; i < active_nr; i++) {
1473                const struct cache_entry *ce = active_cache[i];
1474                if (!ce_stage(ce))
1475                        continue;
1476                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1477                        prune_num++;
1478                        REALLOC_ARRAY(prune, prune_num);
1479                        prune[prune_num-2] = ce->name;
1480                        prune[prune_num-1] = NULL;
1481                }
1482                while ((i+1 < active_nr) &&
1483                       ce_same_name(ce, active_cache[i+1]))
1484                        i++;
1485        }
1486        clear_pathspec(&revs->prune_data);
1487        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1488                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1489        revs->limited = 1;
1490}
1491
1492static int dotdot_missing(const char *arg, char *dotdot,
1493                          struct rev_info *revs, int symmetric)
1494{
1495        if (revs->ignore_missing)
1496                return 0;
1497        /* de-munge so we report the full argument */
1498        *dotdot = '.';
1499        die(symmetric
1500            ? "Invalid symmetric difference expression %s"
1501            : "Invalid revision range %s", arg);
1502}
1503
1504static int handle_dotdot_1(const char *arg, char *dotdot,
1505                           struct rev_info *revs, int flags,
1506                           int cant_be_filename,
1507                           struct object_context *a_oc,
1508                           struct object_context *b_oc)
1509{
1510        const char *a_name, *b_name;
1511        struct object_id a_oid, b_oid;
1512        struct object *a_obj, *b_obj;
1513        unsigned int a_flags, b_flags;
1514        int symmetric = 0;
1515        unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1516        unsigned int oc_flags = GET_OID_COMMITTISH | GET_OID_RECORD_PATH;
1517
1518        a_name = arg;
1519        if (!*a_name)
1520                a_name = "HEAD";
1521
1522        b_name = dotdot + 2;
1523        if (*b_name == '.') {
1524                symmetric = 1;
1525                b_name++;
1526        }
1527        if (!*b_name)
1528                b_name = "HEAD";
1529
1530        if (get_oid_with_context(a_name, oc_flags, &a_oid, a_oc) ||
1531            get_oid_with_context(b_name, oc_flags, &b_oid, b_oc))
1532                return -1;
1533
1534        if (!cant_be_filename) {
1535                *dotdot = '.';
1536                verify_non_filename(revs->prefix, arg);
1537                *dotdot = '\0';
1538        }
1539
1540        a_obj = parse_object(&a_oid);
1541        b_obj = parse_object(&b_oid);
1542        if (!a_obj || !b_obj)
1543                return dotdot_missing(arg, dotdot, revs, symmetric);
1544
1545        if (!symmetric) {
1546                /* just A..B */
1547                b_flags = flags;
1548                a_flags = flags_exclude;
1549        } else {
1550                /* A...B -- find merge bases between the two */
1551                struct commit *a, *b;
1552                struct commit_list *exclude;
1553
1554                a = lookup_commit_reference(&a_obj->oid);
1555                b = lookup_commit_reference(&b_obj->oid);
1556                if (!a || !b)
1557                        return dotdot_missing(arg, dotdot, revs, symmetric);
1558
1559                exclude = get_merge_bases(a, b);
1560                add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
1561                                     flags_exclude);
1562                add_pending_commit_list(revs, exclude, flags_exclude);
1563                free_commit_list(exclude);
1564
1565                b_flags = flags;
1566                a_flags = flags | SYMMETRIC_LEFT;
1567        }
1568
1569        a_obj->flags |= a_flags;
1570        b_obj->flags |= b_flags;
1571        add_rev_cmdline(revs, a_obj, a_name, REV_CMD_LEFT, a_flags);
1572        add_rev_cmdline(revs, b_obj, b_name, REV_CMD_RIGHT, b_flags);
1573        add_pending_object_with_path(revs, a_obj, a_name, a_oc->mode, a_oc->path);
1574        add_pending_object_with_path(revs, b_obj, b_name, b_oc->mode, b_oc->path);
1575        return 0;
1576}
1577
1578static int handle_dotdot(const char *arg,
1579                         struct rev_info *revs, int flags,
1580                         int cant_be_filename)
1581{
1582        struct object_context a_oc, b_oc;
1583        char *dotdot = strstr(arg, "..");
1584        int ret;
1585
1586        if (!dotdot)
1587                return -1;
1588
1589        memset(&a_oc, 0, sizeof(a_oc));
1590        memset(&b_oc, 0, sizeof(b_oc));
1591
1592        *dotdot = '\0';
1593        ret = handle_dotdot_1(arg, dotdot, revs, flags, cant_be_filename,
1594                              &a_oc, &b_oc);
1595        *dotdot = '.';
1596
1597        free(a_oc.path);
1598        free(b_oc.path);
1599
1600        return ret;
1601}
1602
1603int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1604{
1605        struct object_context oc;
1606        char *mark;
1607        struct object *object;
1608        struct object_id oid;
1609        int local_flags;
1610        const char *arg = arg_;
1611        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1612        unsigned get_sha1_flags = GET_OID_RECORD_PATH;
1613
1614        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1615
1616        if (!cant_be_filename && !strcmp(arg, "..")) {
1617                /*
1618                 * Just ".."?  That is not a range but the
1619                 * pathspec for the parent directory.
1620                 */
1621                return -1;
1622        }
1623
1624        if (!handle_dotdot(arg, revs, flags, revarg_opt))
1625                return 0;
1626
1627        mark = strstr(arg, "^@");
1628        if (mark && !mark[2]) {
1629                *mark = 0;
1630                if (add_parents_only(revs, arg, flags, 0))
1631                        return 0;
1632                *mark = '^';
1633        }
1634        mark = strstr(arg, "^!");
1635        if (mark && !mark[2]) {
1636                *mark = 0;
1637                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), 0))
1638                        *mark = '^';
1639        }
1640        mark = strstr(arg, "^-");
1641        if (mark) {
1642                int exclude_parent = 1;
1643
1644                if (mark[2]) {
1645                        char *end;
1646                        exclude_parent = strtoul(mark + 2, &end, 10);
1647                        if (*end != '\0' || !exclude_parent)
1648                                return -1;
1649                }
1650
1651                *mark = 0;
1652                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), exclude_parent))
1653                        *mark = '^';
1654        }
1655
1656        local_flags = 0;
1657        if (*arg == '^') {
1658                local_flags = UNINTERESTING | BOTTOM;
1659                arg++;
1660        }
1661
1662        if (revarg_opt & REVARG_COMMITTISH)
1663                get_sha1_flags |= GET_OID_COMMITTISH;
1664
1665        if (get_oid_with_context(arg, get_sha1_flags, &oid, &oc))
1666                return revs->ignore_missing ? 0 : -1;
1667        if (!cant_be_filename)
1668                verify_non_filename(revs->prefix, arg);
1669        object = get_reference(revs, arg, &oid, flags ^ local_flags);
1670        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1671        add_pending_object_with_path(revs, object, arg, oc.mode, oc.path);
1672        free(oc.path);
1673        return 0;
1674}
1675
1676static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1677                                     struct argv_array *prune)
1678{
1679        while (strbuf_getline(sb, stdin) != EOF)
1680                argv_array_push(prune, sb->buf);
1681}
1682
1683static void read_revisions_from_stdin(struct rev_info *revs,
1684                                      struct argv_array *prune)
1685{
1686        struct strbuf sb;
1687        int seen_dashdash = 0;
1688        int save_warning;
1689
1690        save_warning = warn_on_object_refname_ambiguity;
1691        warn_on_object_refname_ambiguity = 0;
1692
1693        strbuf_init(&sb, 1000);
1694        while (strbuf_getline(&sb, stdin) != EOF) {
1695                int len = sb.len;
1696                if (!len)
1697                        break;
1698                if (sb.buf[0] == '-') {
1699                        if (len == 2 && sb.buf[1] == '-') {
1700                                seen_dashdash = 1;
1701                                break;
1702                        }
1703                        die("options not supported in --stdin mode");
1704                }
1705                if (handle_revision_arg(sb.buf, revs, 0,
1706                                        REVARG_CANNOT_BE_FILENAME))
1707                        die("bad revision '%s'", sb.buf);
1708        }
1709        if (seen_dashdash)
1710                read_pathspec_from_stdin(revs, &sb, prune);
1711
1712        strbuf_release(&sb);
1713        warn_on_object_refname_ambiguity = save_warning;
1714}
1715
1716static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1717{
1718        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1719}
1720
1721static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1722{
1723        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1724}
1725
1726static void add_message_grep(struct rev_info *revs, const char *pattern)
1727{
1728        add_grep(revs, pattern, GREP_PATTERN_BODY);
1729}
1730
1731static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1732                               int *unkc, const char **unkv)
1733{
1734        const char *arg = argv[0];
1735        const char *optarg;
1736        int argcount;
1737
1738        /* pseudo revision arguments */
1739        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1740            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1741            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1742            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1743            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1744            !strcmp(arg, "--indexed-objects") ||
1745            starts_with(arg, "--exclude=") ||
1746            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1747            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1748        {
1749                unkv[(*unkc)++] = arg;
1750                return 1;
1751        }
1752
1753        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1754                revs->max_count = atoi(optarg);
1755                revs->no_walk = 0;
1756                return argcount;
1757        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1758                revs->skip_count = atoi(optarg);
1759                return argcount;
1760        } else if ((*arg == '-') && isdigit(arg[1])) {
1761                /* accept -<digit>, like traditional "head" */
1762                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1763                    revs->max_count < 0)
1764                        die("'%s': not a non-negative integer", arg + 1);
1765                revs->no_walk = 0;
1766        } else if (!strcmp(arg, "-n")) {
1767                if (argc <= 1)
1768                        return error("-n requires an argument");
1769                revs->max_count = atoi(argv[1]);
1770                revs->no_walk = 0;
1771                return 2;
1772        } else if (skip_prefix(arg, "-n", &optarg)) {
1773                revs->max_count = atoi(optarg);
1774                revs->no_walk = 0;
1775        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1776                revs->max_age = atoi(optarg);
1777                return argcount;
1778        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1779                revs->max_age = approxidate(optarg);
1780                return argcount;
1781        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1782                revs->max_age = approxidate(optarg);
1783                return argcount;
1784        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1785                revs->min_age = atoi(optarg);
1786                return argcount;
1787        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1788                revs->min_age = approxidate(optarg);
1789                return argcount;
1790        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1791                revs->min_age = approxidate(optarg);
1792                return argcount;
1793        } else if (!strcmp(arg, "--first-parent")) {
1794                revs->first_parent_only = 1;
1795        } else if (!strcmp(arg, "--ancestry-path")) {
1796                revs->ancestry_path = 1;
1797                revs->simplify_history = 0;
1798                revs->limited = 1;
1799        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1800                init_reflog_walk(&revs->reflog_info);
1801        } else if (!strcmp(arg, "--default")) {
1802                if (argc <= 1)
1803                        return error("bad --default argument");
1804                revs->def = argv[1];
1805                return 2;
1806        } else if (!strcmp(arg, "--merge")) {
1807                revs->show_merge = 1;
1808        } else if (!strcmp(arg, "--topo-order")) {
1809                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1810                revs->topo_order = 1;
1811        } else if (!strcmp(arg, "--simplify-merges")) {
1812                revs->simplify_merges = 1;
1813                revs->topo_order = 1;
1814                revs->rewrite_parents = 1;
1815                revs->simplify_history = 0;
1816                revs->limited = 1;
1817        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1818                revs->simplify_merges = 1;
1819                revs->topo_order = 1;
1820                revs->rewrite_parents = 1;
1821                revs->simplify_history = 0;
1822                revs->simplify_by_decoration = 1;
1823                revs->limited = 1;
1824                revs->prune = 1;
1825                load_ref_decorations(DECORATE_SHORT_REFS);
1826        } else if (!strcmp(arg, "--date-order")) {
1827                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1828                revs->topo_order = 1;
1829        } else if (!strcmp(arg, "--author-date-order")) {
1830                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1831                revs->topo_order = 1;
1832        } else if (!strcmp(arg, "--early-output")) {
1833                revs->early_output = 100;
1834                revs->topo_order = 1;
1835        } else if (skip_prefix(arg, "--early-output=", &optarg)) {
1836                if (strtoul_ui(optarg, 10, &revs->early_output) < 0)
1837                        die("'%s': not a non-negative integer", optarg);
1838                revs->topo_order = 1;
1839        } else if (!strcmp(arg, "--parents")) {
1840                revs->rewrite_parents = 1;
1841                revs->print_parents = 1;
1842        } else if (!strcmp(arg, "--dense")) {
1843                revs->dense = 1;
1844        } else if (!strcmp(arg, "--sparse")) {
1845                revs->dense = 0;
1846        } else if (!strcmp(arg, "--show-all")) {
1847                revs->show_all = 1;
1848        } else if (!strcmp(arg, "--remove-empty")) {
1849                revs->remove_empty_trees = 1;
1850        } else if (!strcmp(arg, "--merges")) {
1851                revs->min_parents = 2;
1852        } else if (!strcmp(arg, "--no-merges")) {
1853                revs->max_parents = 1;
1854        } else if (skip_prefix(arg, "--min-parents=", &optarg)) {
1855                revs->min_parents = atoi(optarg);
1856        } else if (!strcmp(arg, "--no-min-parents")) {
1857                revs->min_parents = 0;
1858        } else if (skip_prefix(arg, "--max-parents=", &optarg)) {
1859                revs->max_parents = atoi(optarg);
1860        } else if (!strcmp(arg, "--no-max-parents")) {
1861                revs->max_parents = -1;
1862        } else if (!strcmp(arg, "--boundary")) {
1863                revs->boundary = 1;
1864        } else if (!strcmp(arg, "--left-right")) {
1865                revs->left_right = 1;
1866        } else if (!strcmp(arg, "--left-only")) {
1867                if (revs->right_only)
1868                        die("--left-only is incompatible with --right-only"
1869                            " or --cherry");
1870                revs->left_only = 1;
1871        } else if (!strcmp(arg, "--right-only")) {
1872                if (revs->left_only)
1873                        die("--right-only is incompatible with --left-only");
1874                revs->right_only = 1;
1875        } else if (!strcmp(arg, "--cherry")) {
1876                if (revs->left_only)
1877                        die("--cherry is incompatible with --left-only");
1878                revs->cherry_mark = 1;
1879                revs->right_only = 1;
1880                revs->max_parents = 1;
1881                revs->limited = 1;
1882        } else if (!strcmp(arg, "--count")) {
1883                revs->count = 1;
1884        } else if (!strcmp(arg, "--cherry-mark")) {
1885                if (revs->cherry_pick)
1886                        die("--cherry-mark is incompatible with --cherry-pick");
1887                revs->cherry_mark = 1;
1888                revs->limited = 1; /* needs limit_list() */
1889        } else if (!strcmp(arg, "--cherry-pick")) {
1890                if (revs->cherry_mark)
1891                        die("--cherry-pick is incompatible with --cherry-mark");
1892                revs->cherry_pick = 1;
1893                revs->limited = 1;
1894        } else if (!strcmp(arg, "--objects")) {
1895                revs->tag_objects = 1;
1896                revs->tree_objects = 1;
1897                revs->blob_objects = 1;
1898        } else if (!strcmp(arg, "--objects-edge")) {
1899                revs->tag_objects = 1;
1900                revs->tree_objects = 1;
1901                revs->blob_objects = 1;
1902                revs->edge_hint = 1;
1903        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1904                revs->tag_objects = 1;
1905                revs->tree_objects = 1;
1906                revs->blob_objects = 1;
1907                revs->edge_hint = 1;
1908                revs->edge_hint_aggressive = 1;
1909        } else if (!strcmp(arg, "--verify-objects")) {
1910                revs->tag_objects = 1;
1911                revs->tree_objects = 1;
1912                revs->blob_objects = 1;
1913                revs->verify_objects = 1;
1914        } else if (!strcmp(arg, "--unpacked")) {
1915                revs->unpacked = 1;
1916        } else if (starts_with(arg, "--unpacked=")) {
1917                die("--unpacked=<packfile> no longer supported.");
1918        } else if (!strcmp(arg, "-r")) {
1919                revs->diff = 1;
1920                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1921        } else if (!strcmp(arg, "-t")) {
1922                revs->diff = 1;
1923                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1924                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1925        } else if (!strcmp(arg, "-m")) {
1926                revs->ignore_merges = 0;
1927        } else if (!strcmp(arg, "-c")) {
1928                revs->diff = 1;
1929                revs->dense_combined_merges = 0;
1930                revs->combine_merges = 1;
1931        } else if (!strcmp(arg, "--cc")) {
1932                revs->diff = 1;
1933                revs->dense_combined_merges = 1;
1934                revs->combine_merges = 1;
1935        } else if (!strcmp(arg, "-v")) {
1936                revs->verbose_header = 1;
1937        } else if (!strcmp(arg, "--pretty")) {
1938                revs->verbose_header = 1;
1939                revs->pretty_given = 1;
1940                get_commit_format(NULL, revs);
1941        } else if (skip_prefix(arg, "--pretty=", &optarg) ||
1942                   skip_prefix(arg, "--format=", &optarg)) {
1943                /*
1944                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1945                 * not allowed, since the argument is optional.
1946                 */
1947                revs->verbose_header = 1;
1948                revs->pretty_given = 1;
1949                get_commit_format(optarg, revs);
1950        } else if (!strcmp(arg, "--expand-tabs")) {
1951                revs->expand_tabs_in_log = 8;
1952        } else if (!strcmp(arg, "--no-expand-tabs")) {
1953                revs->expand_tabs_in_log = 0;
1954        } else if (skip_prefix(arg, "--expand-tabs=", &arg)) {
1955                int val;
1956                if (strtol_i(arg, 10, &val) < 0 || val < 0)
1957                        die("'%s': not a non-negative integer", arg);
1958                revs->expand_tabs_in_log = val;
1959        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1960                revs->show_notes = 1;
1961                revs->show_notes_given = 1;
1962                revs->notes_opt.use_default_notes = 1;
1963        } else if (!strcmp(arg, "--show-signature")) {
1964                revs->show_signature = 1;
1965        } else if (!strcmp(arg, "--no-show-signature")) {
1966                revs->show_signature = 0;
1967        } else if (!strcmp(arg, "--show-linear-break")) {
1968                revs->break_bar = "                    ..........";
1969                revs->track_linear = 1;
1970                revs->track_first_time = 1;
1971        } else if (skip_prefix(arg, "--show-linear-break=", &optarg)) {
1972                revs->break_bar = xstrdup(optarg);
1973                revs->track_linear = 1;
1974                revs->track_first_time = 1;
1975        } else if (skip_prefix(arg, "--show-notes=", &optarg) ||
1976                   skip_prefix(arg, "--notes=", &optarg)) {
1977                struct strbuf buf = STRBUF_INIT;
1978                revs->show_notes = 1;
1979                revs->show_notes_given = 1;
1980                if (starts_with(arg, "--show-notes=") &&
1981                    revs->notes_opt.use_default_notes < 0)
1982                        revs->notes_opt.use_default_notes = 1;
1983                strbuf_addstr(&buf, optarg);
1984                expand_notes_ref(&buf);
1985                string_list_append(&revs->notes_opt.extra_notes_refs,
1986                                   strbuf_detach(&buf, NULL));
1987        } else if (!strcmp(arg, "--no-notes")) {
1988                revs->show_notes = 0;
1989                revs->show_notes_given = 1;
1990                revs->notes_opt.use_default_notes = -1;
1991                /* we have been strdup'ing ourselves, so trick
1992                 * string_list into free()ing strings */
1993                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
1994                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
1995                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
1996        } else if (!strcmp(arg, "--standard-notes")) {
1997                revs->show_notes_given = 1;
1998                revs->notes_opt.use_default_notes = 1;
1999        } else if (!strcmp(arg, "--no-standard-notes")) {
2000                revs->notes_opt.use_default_notes = 0;
2001        } else if (!strcmp(arg, "--oneline")) {
2002                revs->verbose_header = 1;
2003                get_commit_format("oneline", revs);
2004                revs->pretty_given = 1;
2005                revs->abbrev_commit = 1;
2006        } else if (!strcmp(arg, "--graph")) {
2007                revs->topo_order = 1;
2008                revs->rewrite_parents = 1;
2009                revs->graph = graph_init(revs);
2010        } else if (!strcmp(arg, "--root")) {
2011                revs->show_root_diff = 1;
2012        } else if (!strcmp(arg, "--no-commit-id")) {
2013                revs->no_commit_id = 1;
2014        } else if (!strcmp(arg, "--always")) {
2015                revs->always_show_header = 1;
2016        } else if (!strcmp(arg, "--no-abbrev")) {
2017                revs->abbrev = 0;
2018        } else if (!strcmp(arg, "--abbrev")) {
2019                revs->abbrev = DEFAULT_ABBREV;
2020        } else if (skip_prefix(arg, "--abbrev=", &optarg)) {
2021                revs->abbrev = strtoul(optarg, NULL, 10);
2022                if (revs->abbrev < MINIMUM_ABBREV)
2023                        revs->abbrev = MINIMUM_ABBREV;
2024                else if (revs->abbrev > 40)
2025                        revs->abbrev = 40;
2026        } else if (!strcmp(arg, "--abbrev-commit")) {
2027                revs->abbrev_commit = 1;
2028                revs->abbrev_commit_given = 1;
2029        } else if (!strcmp(arg, "--no-abbrev-commit")) {
2030                revs->abbrev_commit = 0;
2031        } else if (!strcmp(arg, "--full-diff")) {
2032                revs->diff = 1;
2033                revs->full_diff = 1;
2034        } else if (!strcmp(arg, "--full-history")) {
2035                revs->simplify_history = 0;
2036        } else if (!strcmp(arg, "--relative-date")) {
2037                revs->date_mode.type = DATE_RELATIVE;
2038                revs->date_mode_explicit = 1;
2039        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
2040                parse_date_format(optarg, &revs->date_mode);
2041                revs->date_mode_explicit = 1;
2042                return argcount;
2043        } else if (!strcmp(arg, "--log-size")) {
2044                revs->show_log_size = 1;
2045        }
2046        /*
2047         * Grepping the commit log
2048         */
2049        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
2050                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
2051                return argcount;
2052        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
2053                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
2054                return argcount;
2055        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
2056                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
2057                return argcount;
2058        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
2059                add_message_grep(revs, optarg);
2060                return argcount;
2061        } else if (!strcmp(arg, "--grep-debug")) {
2062                revs->grep_filter.debug = 1;
2063        } else if (!strcmp(arg, "--basic-regexp")) {
2064                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_BRE;
2065        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
2066                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_ERE;
2067        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
2068                revs->grep_filter.ignore_case = 1;
2069                DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
2070        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
2071                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
2072        } else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
2073                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
2074        } else if (!strcmp(arg, "--all-match")) {
2075                revs->grep_filter.all_match = 1;
2076        } else if (!strcmp(arg, "--invert-grep")) {
2077                revs->invert_grep = 1;
2078        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
2079                if (strcmp(optarg, "none"))
2080                        git_log_output_encoding = xstrdup(optarg);
2081                else
2082                        git_log_output_encoding = "";
2083                return argcount;
2084        } else if (!strcmp(arg, "--reverse")) {
2085                revs->reverse ^= 1;
2086        } else if (!strcmp(arg, "--children")) {
2087                revs->children.name = "children";
2088                revs->limited = 1;
2089        } else if (!strcmp(arg, "--ignore-missing")) {
2090                revs->ignore_missing = 1;
2091        } else {
2092                int opts = diff_opt_parse(&revs->diffopt, argv, argc, revs->prefix);
2093                if (!opts)
2094                        unkv[(*unkc)++] = arg;
2095                return opts;
2096        }
2097        if (revs->graph && revs->track_linear)
2098                die("--show-linear-break and --graph are incompatible");
2099
2100        return 1;
2101}
2102
2103void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2104                        const struct option *options,
2105                        const char * const usagestr[])
2106{
2107        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2108                                    &ctx->cpidx, ctx->out);
2109        if (n <= 0) {
2110                error("unknown option `%s'", ctx->argv[0]);
2111                usage_with_options(usagestr, options);
2112        }
2113        ctx->argv += n;
2114        ctx->argc -= n;
2115}
2116
2117static int for_each_bisect_ref(struct ref_store *refs, each_ref_fn fn,
2118                               void *cb_data, const char *term)
2119{
2120        struct strbuf bisect_refs = STRBUF_INIT;
2121        int status;
2122        strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
2123        status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data, 0);
2124        strbuf_release(&bisect_refs);
2125        return status;
2126}
2127
2128static int for_each_bad_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2129{
2130        return for_each_bisect_ref(refs, fn, cb_data, term_bad);
2131}
2132
2133static int for_each_good_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2134{
2135        return for_each_bisect_ref(refs, fn, cb_data, term_good);
2136}
2137
2138static int handle_revision_pseudo_opt(const char *submodule,
2139                                struct rev_info *revs,
2140                                int argc, const char **argv, int *flags)
2141{
2142        const char *arg = argv[0];
2143        const char *optarg;
2144        struct ref_store *refs;
2145        int argcount;
2146
2147        if (submodule) {
2148                /*
2149                 * We need some something like get_submodule_worktrees()
2150                 * before we can go through all worktrees of a submodule,
2151                 * .e.g with adding all HEADs from --all, which is not
2152                 * supported right now, so stick to single worktree.
2153                 */
2154                if (!revs->single_worktree)
2155                        die("BUG: --single-worktree cannot be used together with submodule");
2156                refs = get_submodule_ref_store(submodule);
2157        } else
2158                refs = get_main_ref_store();
2159
2160        /*
2161         * NOTE!
2162         *
2163         * Commands like "git shortlog" will not accept the options below
2164         * unless parse_revision_opt queues them (as opposed to erroring
2165         * out).
2166         *
2167         * When implementing your new pseudo-option, remember to
2168         * register it in the list at the top of handle_revision_opt.
2169         */
2170        if (!strcmp(arg, "--all")) {
2171                handle_refs(refs, revs, *flags, refs_for_each_ref);
2172                handle_refs(refs, revs, *flags, refs_head_ref);
2173                if (!revs->single_worktree) {
2174                        struct all_refs_cb cb;
2175
2176                        init_all_refs_cb(&cb, revs, *flags);
2177                        other_head_refs(handle_one_ref, &cb);
2178                }
2179                clear_ref_exclusion(&revs->ref_excludes);
2180        } else if (!strcmp(arg, "--branches")) {
2181                handle_refs(refs, revs, *flags, refs_for_each_branch_ref);
2182                clear_ref_exclusion(&revs->ref_excludes);
2183        } else if (!strcmp(arg, "--bisect")) {
2184                read_bisect_terms(&term_bad, &term_good);
2185                handle_refs(refs, revs, *flags, for_each_bad_bisect_ref);
2186                handle_refs(refs, revs, *flags ^ (UNINTERESTING | BOTTOM),
2187                            for_each_good_bisect_ref);
2188                revs->bisect = 1;
2189        } else if (!strcmp(arg, "--tags")) {
2190                handle_refs(refs, revs, *flags, refs_for_each_tag_ref);
2191                clear_ref_exclusion(&revs->ref_excludes);
2192        } else if (!strcmp(arg, "--remotes")) {
2193                handle_refs(refs, revs, *flags, refs_for_each_remote_ref);
2194                clear_ref_exclusion(&revs->ref_excludes);
2195        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2196                struct all_refs_cb cb;
2197                init_all_refs_cb(&cb, revs, *flags);
2198                for_each_glob_ref(handle_one_ref, optarg, &cb);
2199                clear_ref_exclusion(&revs->ref_excludes);
2200                return argcount;
2201        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2202                add_ref_exclusion(&revs->ref_excludes, optarg);
2203                return argcount;
2204        } else if (skip_prefix(arg, "--branches=", &optarg)) {
2205                struct all_refs_cb cb;
2206                init_all_refs_cb(&cb, revs, *flags);
2207                for_each_glob_ref_in(handle_one_ref, optarg, "refs/heads/", &cb);
2208                clear_ref_exclusion(&revs->ref_excludes);
2209        } else if (skip_prefix(arg, "--tags=", &optarg)) {
2210                struct all_refs_cb cb;
2211                init_all_refs_cb(&cb, revs, *flags);
2212                for_each_glob_ref_in(handle_one_ref, optarg, "refs/tags/", &cb);
2213                clear_ref_exclusion(&revs->ref_excludes);
2214        } else if (skip_prefix(arg, "--remotes=", &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/remotes/", &cb);
2218                clear_ref_exclusion(&revs->ref_excludes);
2219        } else if (!strcmp(arg, "--reflog")) {
2220                add_reflogs_to_pending(revs, *flags);
2221        } else if (!strcmp(arg, "--indexed-objects")) {
2222                add_index_objects_to_pending(revs, *flags);
2223        } else if (!strcmp(arg, "--not")) {
2224                *flags ^= UNINTERESTING | BOTTOM;
2225        } else if (!strcmp(arg, "--no-walk")) {
2226                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2227        } else if (skip_prefix(arg, "--no-walk=", &optarg)) {
2228                /*
2229                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2230                 * not allowed, since the argument is optional.
2231                 */
2232                if (!strcmp(optarg, "sorted"))
2233                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2234                else if (!strcmp(optarg, "unsorted"))
2235                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2236                else
2237                        return error("invalid argument to --no-walk");
2238        } else if (!strcmp(arg, "--do-walk")) {
2239                revs->no_walk = 0;
2240        } else if (!strcmp(arg, "--single-worktree")) {
2241                revs->single_worktree = 1;
2242        } else {
2243                return 0;
2244        }
2245
2246        return 1;
2247}
2248
2249static void NORETURN diagnose_missing_default(const char *def)
2250{
2251        int flags;
2252        const char *refname;
2253
2254        refname = resolve_ref_unsafe(def, 0, NULL, &flags);
2255        if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
2256                die(_("your current branch appears to be broken"));
2257
2258        skip_prefix(refname, "refs/heads/", &refname);
2259        die(_("your current branch '%s' does not have any commits yet"),
2260            refname);
2261}
2262
2263/*
2264 * Parse revision information, filling in the "rev_info" structure,
2265 * and removing the used arguments from the argument list.
2266 *
2267 * Returns the number of arguments left that weren't recognized
2268 * (which are also moved to the head of the argument list)
2269 */
2270int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2271{
2272        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2273        struct argv_array prune_data = ARGV_ARRAY_INIT;
2274        const char *submodule = NULL;
2275
2276        if (opt)
2277                submodule = opt->submodule;
2278
2279        /* First, search for "--" */
2280        if (opt && opt->assume_dashdash) {
2281                seen_dashdash = 1;
2282        } else {
2283                seen_dashdash = 0;
2284                for (i = 1; i < argc; i++) {
2285                        const char *arg = argv[i];
2286                        if (strcmp(arg, "--"))
2287                                continue;
2288                        argv[i] = NULL;
2289                        argc = i;
2290                        if (argv[i + 1])
2291                                argv_array_pushv(&prune_data, argv + i + 1);
2292                        seen_dashdash = 1;
2293                        break;
2294                }
2295        }
2296
2297        /* Second, deal with arguments and options */
2298        flags = 0;
2299        revarg_opt = opt ? opt->revarg_opt : 0;
2300        if (seen_dashdash)
2301                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2302        read_from_stdin = 0;
2303        for (left = i = 1; i < argc; i++) {
2304                const char *arg = argv[i];
2305                if (*arg == '-') {
2306                        int opts;
2307
2308                        opts = handle_revision_pseudo_opt(submodule,
2309                                                revs, argc - i, argv + i,
2310                                                &flags);
2311                        if (opts > 0) {
2312                                i += opts - 1;
2313                                continue;
2314                        }
2315
2316                        if (!strcmp(arg, "--stdin")) {
2317                                if (revs->disable_stdin) {
2318                                        argv[left++] = arg;
2319                                        continue;
2320                                }
2321                                if (read_from_stdin++)
2322                                        die("--stdin given twice?");
2323                                read_revisions_from_stdin(revs, &prune_data);
2324                                continue;
2325                        }
2326
2327                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2328                        if (opts > 0) {
2329                                i += opts - 1;
2330                                continue;
2331                        }
2332                        if (opts < 0)
2333                                exit(128);
2334                        continue;
2335                }
2336
2337
2338                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2339                        int j;
2340                        if (seen_dashdash || *arg == '^')
2341                                die("bad revision '%s'", arg);
2342
2343                        /* If we didn't have a "--":
2344                         * (1) all filenames must exist;
2345                         * (2) all rev-args must not be interpretable
2346                         *     as a valid filename.
2347                         * but the latter we have checked in the main loop.
2348                         */
2349                        for (j = i; j < argc; j++)
2350                                verify_filename(revs->prefix, argv[j], j == i);
2351
2352                        argv_array_pushv(&prune_data, argv + i);
2353                        break;
2354                }
2355                else
2356                        got_rev_arg = 1;
2357        }
2358
2359        if (prune_data.argc) {
2360                /*
2361                 * If we need to introduce the magic "a lone ':' means no
2362                 * pathspec whatsoever", here is the place to do so.
2363                 *
2364                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2365                 *      prune_data.nr = 0;
2366                 *      prune_data.alloc = 0;
2367                 *      free(prune_data.path);
2368                 *      prune_data.path = NULL;
2369                 * } else {
2370                 *      terminate prune_data.alloc with NULL and
2371                 *      call init_pathspec() to set revs->prune_data here.
2372                 * }
2373                 */
2374                parse_pathspec(&revs->prune_data, 0, 0,
2375                               revs->prefix, prune_data.argv);
2376        }
2377        argv_array_clear(&prune_data);
2378
2379        if (revs->def == NULL)
2380                revs->def = opt ? opt->def : NULL;
2381        if (opt && opt->tweak)
2382                opt->tweak(revs, opt);
2383        if (revs->show_merge)
2384                prepare_show_merge(revs);
2385        if (revs->def && !revs->pending.nr && !revs->rev_input_given && !got_rev_arg) {
2386                struct object_id oid;
2387                struct object *object;
2388                struct object_context oc;
2389                if (get_oid_with_context(revs->def, 0, &oid, &oc))
2390                        diagnose_missing_default(revs->def);
2391                object = get_reference(revs, revs->def, &oid, 0);
2392                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2393        }
2394
2395        /* Did the user ask for any diff output? Run the diff! */
2396        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2397                revs->diff = 1;
2398
2399        /* Pickaxe, diff-filter and rename following need diffs */
2400        if (revs->diffopt.pickaxe ||
2401            revs->diffopt.filter ||
2402            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2403                revs->diff = 1;
2404
2405        if (revs->topo_order)
2406                revs->limited = 1;
2407
2408        if (revs->prune_data.nr) {
2409                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2410                /* Can't prune commits with rename following: the paths change.. */
2411                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2412                        revs->prune = 1;
2413                if (!revs->full_diff)
2414                        copy_pathspec(&revs->diffopt.pathspec,
2415                                      &revs->prune_data);
2416        }
2417        if (revs->combine_merges)
2418                revs->ignore_merges = 0;
2419        revs->diffopt.abbrev = revs->abbrev;
2420
2421        if (revs->line_level_traverse) {
2422                revs->limited = 1;
2423                revs->topo_order = 1;
2424        }
2425
2426        diff_setup_done(&revs->diffopt);
2427
2428        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2429                                 &revs->grep_filter);
2430        compile_grep_patterns(&revs->grep_filter);
2431
2432        if (revs->reverse && revs->reflog_info)
2433                die("cannot combine --reverse with --walk-reflogs");
2434        if (revs->reflog_info && revs->limited)
2435                die("cannot combine --walk-reflogs with history-limiting options");
2436        if (revs->rewrite_parents && revs->children.name)
2437                die("cannot combine --parents and --children");
2438
2439        /*
2440         * Limitations on the graph functionality
2441         */
2442        if (revs->reverse && revs->graph)
2443                die("cannot combine --reverse with --graph");
2444
2445        if (revs->reflog_info && revs->graph)
2446                die("cannot combine --walk-reflogs with --graph");
2447        if (revs->no_walk && revs->graph)
2448                die("cannot combine --no-walk with --graph");
2449        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2450                die("cannot use --grep-reflog without --walk-reflogs");
2451
2452        if (revs->first_parent_only && revs->bisect)
2453                die(_("--first-parent is incompatible with --bisect"));
2454
2455        if (revs->expand_tabs_in_log < 0)
2456                revs->expand_tabs_in_log = revs->expand_tabs_in_log_default;
2457
2458        return left;
2459}
2460
2461static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2462{
2463        struct commit_list *l = xcalloc(1, sizeof(*l));
2464
2465        l->item = child;
2466        l->next = add_decoration(&revs->children, &parent->object, l);
2467}
2468
2469static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2470{
2471        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2472        struct commit_list **pp, *p;
2473        int surviving_parents;
2474
2475        /* Examine existing parents while marking ones we have seen... */
2476        pp = &commit->parents;
2477        surviving_parents = 0;
2478        while ((p = *pp) != NULL) {
2479                struct commit *parent = p->item;
2480                if (parent->object.flags & TMP_MARK) {
2481                        *pp = p->next;
2482                        if (ts)
2483                                compact_treesame(revs, commit, surviving_parents);
2484                        continue;
2485                }
2486                parent->object.flags |= TMP_MARK;
2487                surviving_parents++;
2488                pp = &p->next;
2489        }
2490        /* clear the temporary mark */
2491        for (p = commit->parents; p; p = p->next) {
2492                p->item->object.flags &= ~TMP_MARK;
2493        }
2494        /* no update_treesame() - removing duplicates can't affect TREESAME */
2495        return surviving_parents;
2496}
2497
2498struct merge_simplify_state {
2499        struct commit *simplified;
2500};
2501
2502static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2503{
2504        struct merge_simplify_state *st;
2505
2506        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2507        if (!st) {
2508                st = xcalloc(1, sizeof(*st));
2509                add_decoration(&revs->merge_simplification, &commit->object, st);
2510        }
2511        return st;
2512}
2513
2514static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2515{
2516        struct commit_list *h = reduce_heads(commit->parents);
2517        int i = 0, marked = 0;
2518        struct commit_list *po, *pn;
2519
2520        /* Want these for sanity-checking only */
2521        int orig_cnt = commit_list_count(commit->parents);
2522        int cnt = commit_list_count(h);
2523
2524        /*
2525         * Not ready to remove items yet, just mark them for now, based
2526         * on the output of reduce_heads(). reduce_heads outputs the reduced
2527         * set in its original order, so this isn't too hard.
2528         */
2529        po = commit->parents;
2530        pn = h;
2531        while (po) {
2532                if (pn && po->item == pn->item) {
2533                        pn = pn->next;
2534                        i++;
2535                } else {
2536                        po->item->object.flags |= TMP_MARK;
2537                        marked++;
2538                }
2539                po=po->next;
2540        }
2541
2542        if (i != cnt || cnt+marked != orig_cnt)
2543                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2544
2545        free_commit_list(h);
2546
2547        return marked;
2548}
2549
2550static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2551{
2552        struct commit_list *p;
2553        int marked = 0;
2554
2555        for (p = commit->parents; p; p = p->next) {
2556                struct commit *parent = p->item;
2557                if (!parent->parents && (parent->object.flags & TREESAME)) {
2558                        parent->object.flags |= TMP_MARK;
2559                        marked++;
2560                }
2561        }
2562
2563        return marked;
2564}
2565
2566/*
2567 * Awkward naming - this means one parent we are TREESAME to.
2568 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2569 * empty tree). Better name suggestions?
2570 */
2571static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2572{
2573        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2574        struct commit *unmarked = NULL, *marked = NULL;
2575        struct commit_list *p;
2576        unsigned n;
2577
2578        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2579                if (ts->treesame[n]) {
2580                        if (p->item->object.flags & TMP_MARK) {
2581                                if (!marked)
2582                                        marked = p->item;
2583                        } else {
2584                                if (!unmarked) {
2585                                        unmarked = p->item;
2586                                        break;
2587                                }
2588                        }
2589                }
2590        }
2591
2592        /*
2593         * If we are TREESAME to a marked-for-deletion parent, but not to any
2594         * unmarked parents, unmark the first TREESAME parent. This is the
2595         * parent that the default simplify_history==1 scan would have followed,
2596         * and it doesn't make sense to omit that path when asking for a
2597         * simplified full history. Retaining it improves the chances of
2598         * understanding odd missed merges that took an old version of a file.
2599         *
2600         * Example:
2601         *
2602         *   I--------*X       A modified the file, but mainline merge X used
2603         *    \       /        "-s ours", so took the version from I. X is
2604         *     `-*A--'         TREESAME to I and !TREESAME to A.
2605         *
2606         * Default log from X would produce "I". Without this check,
2607         * --full-history --simplify-merges would produce "I-A-X", showing
2608         * the merge commit X and that it changed A, but not making clear that
2609         * it had just taken the I version. With this check, the topology above
2610         * is retained.
2611         *
2612         * Note that it is possible that the simplification chooses a different
2613         * TREESAME parent from the default, in which case this test doesn't
2614         * activate, and we _do_ drop the default parent. Example:
2615         *
2616         *   I------X         A modified the file, but it was reverted in B,
2617         *    \    /          meaning mainline merge X is TREESAME to both
2618         *    *A-*B           parents.
2619         *
2620         * Default log would produce "I" by following the first parent;
2621         * --full-history --simplify-merges will produce "I-A-B". But this is a
2622         * reasonable result - it presents a logical full history leading from
2623         * I to X, and X is not an important merge.
2624         */
2625        if (!unmarked && marked) {
2626                marked->object.flags &= ~TMP_MARK;
2627                return 1;
2628        }
2629
2630        return 0;
2631}
2632
2633static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2634{
2635        struct commit_list **pp, *p;
2636        int nth_parent, removed = 0;
2637
2638        pp = &commit->parents;
2639        nth_parent = 0;
2640        while ((p = *pp) != NULL) {
2641                struct commit *parent = p->item;
2642                if (parent->object.flags & TMP_MARK) {
2643                        parent->object.flags &= ~TMP_MARK;
2644                        *pp = p->next;
2645                        free(p);
2646                        removed++;
2647                        compact_treesame(revs, commit, nth_parent);
2648                        continue;
2649                }
2650                pp = &p->next;
2651                nth_parent++;
2652        }
2653
2654        /* Removing parents can only increase TREESAMEness */
2655        if (removed && !(commit->object.flags & TREESAME))
2656                update_treesame(revs, commit);
2657
2658        return nth_parent;
2659}
2660
2661static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2662{
2663        struct commit_list *p;
2664        struct commit *parent;
2665        struct merge_simplify_state *st, *pst;
2666        int cnt;
2667
2668        st = locate_simplify_state(revs, commit);
2669
2670        /*
2671         * Have we handled this one?
2672         */
2673        if (st->simplified)
2674                return tail;
2675
2676        /*
2677         * An UNINTERESTING commit simplifies to itself, so does a
2678         * root commit.  We do not rewrite parents of such commit
2679         * anyway.
2680         */
2681        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2682                st->simplified = commit;
2683                return tail;
2684        }
2685
2686        /*
2687         * Do we know what commit all of our parents that matter
2688         * should be rewritten to?  Otherwise we are not ready to
2689         * rewrite this one yet.
2690         */
2691        for (cnt = 0, p = commit->parents; p; p = p->next) {
2692                pst = locate_simplify_state(revs, p->item);
2693                if (!pst->simplified) {
2694                        tail = &commit_list_insert(p->item, tail)->next;
2695                        cnt++;
2696                }
2697                if (revs->first_parent_only)
2698                        break;
2699        }
2700        if (cnt) {
2701                tail = &commit_list_insert(commit, tail)->next;
2702                return tail;
2703        }
2704
2705        /*
2706         * Rewrite our list of parents. Note that this cannot
2707         * affect our TREESAME flags in any way - a commit is
2708         * always TREESAME to its simplification.
2709         */
2710        for (p = commit->parents; p; p = p->next) {
2711                pst = locate_simplify_state(revs, p->item);
2712                p->item = pst->simplified;
2713                if (revs->first_parent_only)
2714                        break;
2715        }
2716
2717        if (revs->first_parent_only)
2718                cnt = 1;
2719        else
2720                cnt = remove_duplicate_parents(revs, commit);
2721
2722        /*
2723         * It is possible that we are a merge and one side branch
2724         * does not have any commit that touches the given paths;
2725         * in such a case, the immediate parent from that branch
2726         * will be rewritten to be the merge base.
2727         *
2728         *      o----X          X: the commit we are looking at;
2729         *     /    /           o: a commit that touches the paths;
2730         * ---o----'
2731         *
2732         * Further, a merge of an independent branch that doesn't
2733         * touch the path will reduce to a treesame root parent:
2734         *
2735         *  ----o----X          X: the commit we are looking at;
2736         *          /           o: a commit that touches the paths;
2737         *         r            r: a root commit not touching the paths
2738         *
2739         * Detect and simplify both cases.
2740         */
2741        if (1 < cnt) {
2742                int marked = mark_redundant_parents(revs, commit);
2743                marked += mark_treesame_root_parents(revs, commit);
2744                if (marked)
2745                        marked -= leave_one_treesame_to_parent(revs, commit);
2746                if (marked)
2747                        cnt = remove_marked_parents(revs, commit);
2748        }
2749
2750        /*
2751         * A commit simplifies to itself if it is a root, if it is
2752         * UNINTERESTING, if it touches the given paths, or if it is a
2753         * merge and its parents don't simplify to one relevant commit
2754         * (the first two cases are already handled at the beginning of
2755         * this function).
2756         *
2757         * Otherwise, it simplifies to what its sole relevant parent
2758         * simplifies to.
2759         */
2760        if (!cnt ||
2761            (commit->object.flags & UNINTERESTING) ||
2762            !(commit->object.flags & TREESAME) ||
2763            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2764                st->simplified = commit;
2765        else {
2766                pst = locate_simplify_state(revs, parent);
2767                st->simplified = pst->simplified;
2768        }
2769        return tail;
2770}
2771
2772static void simplify_merges(struct rev_info *revs)
2773{
2774        struct commit_list *list, *next;
2775        struct commit_list *yet_to_do, **tail;
2776        struct commit *commit;
2777
2778        if (!revs->prune)
2779                return;
2780
2781        /* feed the list reversed */
2782        yet_to_do = NULL;
2783        for (list = revs->commits; list; list = next) {
2784                commit = list->item;
2785                next = list->next;
2786                /*
2787                 * Do not free(list) here yet; the original list
2788                 * is used later in this function.
2789                 */
2790                commit_list_insert(commit, &yet_to_do);
2791        }
2792        while (yet_to_do) {
2793                list = yet_to_do;
2794                yet_to_do = NULL;
2795                tail = &yet_to_do;
2796                while (list) {
2797                        commit = pop_commit(&list);
2798                        tail = simplify_one(revs, commit, tail);
2799                }
2800        }
2801
2802        /* clean up the result, removing the simplified ones */
2803        list = revs->commits;
2804        revs->commits = NULL;
2805        tail = &revs->commits;
2806        while (list) {
2807                struct merge_simplify_state *st;
2808
2809                commit = pop_commit(&list);
2810                st = locate_simplify_state(revs, commit);
2811                if (st->simplified == commit)
2812                        tail = &commit_list_insert(commit, tail)->next;
2813        }
2814}
2815
2816static void set_children(struct rev_info *revs)
2817{
2818        struct commit_list *l;
2819        for (l = revs->commits; l; l = l->next) {
2820                struct commit *commit = l->item;
2821                struct commit_list *p;
2822
2823                for (p = commit->parents; p; p = p->next)
2824                        add_child(revs, p->item, commit);
2825        }
2826}
2827
2828void reset_revision_walk(void)
2829{
2830        clear_object_flags(SEEN | ADDED | SHOWN);
2831}
2832
2833int prepare_revision_walk(struct rev_info *revs)
2834{
2835        int i;
2836        struct object_array old_pending;
2837        struct commit_list **next = &revs->commits;
2838
2839        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2840        revs->pending.nr = 0;
2841        revs->pending.alloc = 0;
2842        revs->pending.objects = NULL;
2843        for (i = 0; i < old_pending.nr; i++) {
2844                struct object_array_entry *e = old_pending.objects + i;
2845                struct commit *commit = handle_commit(revs, e);
2846                if (commit) {
2847                        if (!(commit->object.flags & SEEN)) {
2848                                commit->object.flags |= SEEN;
2849                                next = commit_list_append(commit, next);
2850                        }
2851                }
2852        }
2853        if (!revs->leak_pending)
2854                object_array_clear(&old_pending);
2855
2856        /* Signal whether we need per-parent treesame decoration */
2857        if (revs->simplify_merges ||
2858            (revs->limited && limiting_can_increase_treesame(revs)))
2859                revs->treesame.name = "treesame";
2860
2861        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2862                commit_list_sort_by_date(&revs->commits);
2863        if (revs->no_walk)
2864                return 0;
2865        if (revs->limited)
2866                if (limit_list(revs) < 0)
2867                        return -1;
2868        if (revs->topo_order)
2869                sort_in_topological_order(&revs->commits, revs->sort_order);
2870        if (revs->line_level_traverse)
2871                line_log_filter(revs);
2872        if (revs->simplify_merges)
2873                simplify_merges(revs);
2874        if (revs->children.name)
2875                set_children(revs);
2876        return 0;
2877}
2878
2879static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2880{
2881        struct commit_list *cache = NULL;
2882
2883        for (;;) {
2884                struct commit *p = *pp;
2885                if (!revs->limited)
2886                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2887                                return rewrite_one_error;
2888                if (p->object.flags & UNINTERESTING)
2889                        return rewrite_one_ok;
2890                if (!(p->object.flags & TREESAME))
2891                        return rewrite_one_ok;
2892                if (!p->parents)
2893                        return rewrite_one_noparents;
2894                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2895                        return rewrite_one_ok;
2896                *pp = p;
2897        }
2898}
2899
2900int rewrite_parents(struct rev_info *revs, struct commit *commit,
2901        rewrite_parent_fn_t rewrite_parent)
2902{
2903        struct commit_list **pp = &commit->parents;
2904        while (*pp) {
2905                struct commit_list *parent = *pp;
2906                switch (rewrite_parent(revs, &parent->item)) {
2907                case rewrite_one_ok:
2908                        break;
2909                case rewrite_one_noparents:
2910                        *pp = parent->next;
2911                        continue;
2912                case rewrite_one_error:
2913                        return -1;
2914                }
2915                pp = &parent->next;
2916        }
2917        remove_duplicate_parents(revs, commit);
2918        return 0;
2919}
2920
2921static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2922{
2923        char *person, *endp;
2924        size_t len, namelen, maillen;
2925        const char *name;
2926        const char *mail;
2927        struct ident_split ident;
2928
2929        person = strstr(buf->buf, what);
2930        if (!person)
2931                return 0;
2932
2933        person += strlen(what);
2934        endp = strchr(person, '\n');
2935        if (!endp)
2936                return 0;
2937
2938        len = endp - person;
2939
2940        if (split_ident_line(&ident, person, len))
2941                return 0;
2942
2943        mail = ident.mail_begin;
2944        maillen = ident.mail_end - ident.mail_begin;
2945        name = ident.name_begin;
2946        namelen = ident.name_end - ident.name_begin;
2947
2948        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2949                struct strbuf namemail = STRBUF_INIT;
2950
2951                strbuf_addf(&namemail, "%.*s <%.*s>",
2952                            (int)namelen, name, (int)maillen, mail);
2953
2954                strbuf_splice(buf, ident.name_begin - buf->buf,
2955                              ident.mail_end - ident.name_begin + 1,
2956                              namemail.buf, namemail.len);
2957
2958                strbuf_release(&namemail);
2959
2960                return 1;
2961        }
2962
2963        return 0;
2964}
2965
2966static int commit_match(struct commit *commit, struct rev_info *opt)
2967{
2968        int retval;
2969        const char *encoding;
2970        const char *message;
2971        struct strbuf buf = STRBUF_INIT;
2972
2973        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2974                return 1;
2975
2976        /* Prepend "fake" headers as needed */
2977        if (opt->grep_filter.use_reflog_filter) {
2978                strbuf_addstr(&buf, "reflog ");
2979                get_reflog_message(&buf, opt->reflog_info);
2980                strbuf_addch(&buf, '\n');
2981        }
2982
2983        /*
2984         * We grep in the user's output encoding, under the assumption that it
2985         * is the encoding they are most likely to write their grep pattern
2986         * for. In addition, it means we will match the "notes" encoding below,
2987         * so we will not end up with a buffer that has two different encodings
2988         * in it.
2989         */
2990        encoding = get_log_output_encoding();
2991        message = logmsg_reencode(commit, NULL, encoding);
2992
2993        /* Copy the commit to temporary if we are using "fake" headers */
2994        if (buf.len)
2995                strbuf_addstr(&buf, message);
2996
2997        if (opt->grep_filter.header_list && opt->mailmap) {
2998                if (!buf.len)
2999                        strbuf_addstr(&buf, message);
3000
3001                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
3002                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
3003        }
3004
3005        /* Append "fake" message parts as needed */
3006        if (opt->show_notes) {
3007                if (!buf.len)
3008                        strbuf_addstr(&buf, message);
3009                format_display_notes(&commit->object.oid, &buf, encoding, 1);
3010        }
3011
3012        /*
3013         * Find either in the original commit message, or in the temporary.
3014         * Note that we cast away the constness of "message" here. It is
3015         * const because it may come from the cached commit buffer. That's OK,
3016         * because we know that it is modifiable heap memory, and that while
3017         * grep_buffer may modify it for speed, it will restore any
3018         * changes before returning.
3019         */
3020        if (buf.len)
3021                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
3022        else
3023                retval = grep_buffer(&opt->grep_filter,
3024                                     (char *)message, strlen(message));
3025        strbuf_release(&buf);
3026        unuse_commit_buffer(commit, message);
3027        return opt->invert_grep ? !retval : retval;
3028}
3029
3030static inline int want_ancestry(const struct rev_info *revs)
3031{
3032        return (revs->rewrite_parents || revs->children.name);
3033}
3034
3035/*
3036 * Return a timestamp to be used for --since/--until comparisons for this
3037 * commit, based on the revision options.
3038 */
3039static timestamp_t comparison_date(const struct rev_info *revs,
3040                                   struct commit *commit)
3041{
3042        return revs->reflog_info ?
3043                get_reflog_timestamp(revs->reflog_info) :
3044                commit->date;
3045}
3046
3047enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
3048{
3049        if (commit->object.flags & SHOWN)
3050                return commit_ignore;
3051        if (revs->unpacked && has_sha1_pack(commit->object.oid.hash))
3052                return commit_ignore;
3053        if (revs->show_all)
3054                return commit_show;
3055        if (commit->object.flags & UNINTERESTING)
3056                return commit_ignore;
3057        if (revs->min_age != -1 &&
3058            comparison_date(revs, commit) > revs->min_age)
3059                        return commit_ignore;
3060        if (revs->min_parents || (revs->max_parents >= 0)) {
3061                int n = commit_list_count(commit->parents);
3062                if ((n < revs->min_parents) ||
3063                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
3064                        return commit_ignore;
3065        }
3066        if (!commit_match(commit, revs))
3067                return commit_ignore;
3068        if (revs->prune && revs->dense) {
3069                /* Commit without changes? */
3070                if (commit->object.flags & TREESAME) {
3071                        int n;
3072                        struct commit_list *p;
3073                        /* drop merges unless we want parenthood */
3074                        if (!want_ancestry(revs))
3075                                return commit_ignore;
3076                        /*
3077                         * If we want ancestry, then need to keep any merges
3078                         * between relevant commits to tie together topology.
3079                         * For consistency with TREESAME and simplification
3080                         * use "relevant" here rather than just INTERESTING,
3081                         * to treat bottom commit(s) as part of the topology.
3082                         */
3083                        for (n = 0, p = commit->parents; p; p = p->next)
3084                                if (relevant_commit(p->item))
3085                                        if (++n >= 2)
3086                                                return commit_show;
3087                        return commit_ignore;
3088                }
3089        }
3090        return commit_show;
3091}
3092
3093define_commit_slab(saved_parents, struct commit_list *);
3094
3095#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
3096
3097/*
3098 * You may only call save_parents() once per commit (this is checked
3099 * for non-root commits).
3100 */
3101static void save_parents(struct rev_info *revs, struct commit *commit)
3102{
3103        struct commit_list **pp;
3104
3105        if (!revs->saved_parents_slab) {
3106                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
3107                init_saved_parents(revs->saved_parents_slab);
3108        }
3109
3110        pp = saved_parents_at(revs->saved_parents_slab, commit);
3111
3112        /*
3113         * When walking with reflogs, we may visit the same commit
3114         * several times: once for each appearance in the reflog.
3115         *
3116         * In this case, save_parents() will be called multiple times.
3117         * We want to keep only the first set of parents.  We need to
3118         * store a sentinel value for an empty (i.e., NULL) parent
3119         * list to distinguish it from a not-yet-saved list, however.
3120         */
3121        if (*pp)
3122                return;
3123        if (commit->parents)
3124                *pp = copy_commit_list(commit->parents);
3125        else
3126                *pp = EMPTY_PARENT_LIST;
3127}
3128
3129static void free_saved_parents(struct rev_info *revs)
3130{
3131        if (revs->saved_parents_slab)
3132                clear_saved_parents(revs->saved_parents_slab);
3133}
3134
3135struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
3136{
3137        struct commit_list *parents;
3138
3139        if (!revs->saved_parents_slab)
3140                return commit->parents;
3141
3142        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3143        if (parents == EMPTY_PARENT_LIST)
3144                return NULL;
3145        return parents;
3146}
3147
3148enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
3149{
3150        enum commit_action action = get_commit_action(revs, commit);
3151
3152        if (action == commit_show &&
3153            !revs->show_all &&
3154            revs->prune && revs->dense && want_ancestry(revs)) {
3155                /*
3156                 * --full-diff on simplified parents is no good: it
3157                 * will show spurious changes from the commits that
3158                 * were elided.  So we save the parents on the side
3159                 * when --full-diff is in effect.
3160                 */
3161                if (revs->full_diff)
3162                        save_parents(revs, commit);
3163                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3164                        return commit_error;
3165        }
3166        return action;
3167}
3168
3169static void track_linear(struct rev_info *revs, struct commit *commit)
3170{
3171        if (revs->track_first_time) {
3172                revs->linear = 1;
3173                revs->track_first_time = 0;
3174        } else {
3175                struct commit_list *p;
3176                for (p = revs->previous_parents; p; p = p->next)
3177                        if (p->item == NULL || /* first commit */
3178                            !oidcmp(&p->item->object.oid, &commit->object.oid))
3179                                break;
3180                revs->linear = p != NULL;
3181        }
3182        if (revs->reverse) {
3183                if (revs->linear)
3184                        commit->object.flags |= TRACK_LINEAR;
3185        }
3186        free_commit_list(revs->previous_parents);
3187        revs->previous_parents = copy_commit_list(commit->parents);
3188}
3189
3190static struct commit *get_revision_1(struct rev_info *revs)
3191{
3192        while (1) {
3193                struct commit *commit;
3194
3195                if (revs->reflog_info)
3196                        commit = next_reflog_entry(revs->reflog_info);
3197                else
3198                        commit = pop_commit(&revs->commits);
3199
3200                if (!commit)
3201                        return NULL;
3202
3203                if (revs->reflog_info)
3204                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3205
3206                /*
3207                 * If we haven't done the list limiting, we need to look at
3208                 * the parents here. We also need to do the date-based limiting
3209                 * that we'd otherwise have done in limit_list().
3210                 */
3211                if (!revs->limited) {
3212                        if (revs->max_age != -1 &&
3213                            comparison_date(revs, commit) < revs->max_age)
3214                                continue;
3215
3216                        if (revs->reflog_info)
3217                                try_to_simplify_commit(revs, commit);
3218                        else if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3219                                if (!revs->ignore_missing_links)
3220                                        die("Failed to traverse parents of commit %s",
3221                                                oid_to_hex(&commit->object.oid));
3222                        }
3223                }
3224
3225                switch (simplify_commit(revs, commit)) {
3226                case commit_ignore:
3227                        continue;
3228                case commit_error:
3229                        die("Failed to simplify parents of commit %s",
3230                            oid_to_hex(&commit->object.oid));
3231                default:
3232                        if (revs->track_linear)
3233                                track_linear(revs, commit);
3234                        return commit;
3235                }
3236        }
3237}
3238
3239/*
3240 * Return true for entries that have not yet been shown.  (This is an
3241 * object_array_each_func_t.)
3242 */
3243static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3244{
3245        return !(entry->item->flags & SHOWN);
3246}
3247
3248/*
3249 * If array is on the verge of a realloc, garbage-collect any entries
3250 * that have already been shown to try to free up some space.
3251 */
3252static void gc_boundary(struct object_array *array)
3253{
3254        if (array->nr == array->alloc)
3255                object_array_filter(array, entry_unshown, NULL);
3256}
3257
3258static void create_boundary_commit_list(struct rev_info *revs)
3259{
3260        unsigned i;
3261        struct commit *c;
3262        struct object_array *array = &revs->boundary_commits;
3263        struct object_array_entry *objects = array->objects;
3264
3265        /*
3266         * If revs->commits is non-NULL at this point, an error occurred in
3267         * get_revision_1().  Ignore the error and continue printing the
3268         * boundary commits anyway.  (This is what the code has always
3269         * done.)
3270         */
3271        if (revs->commits) {
3272                free_commit_list(revs->commits);
3273                revs->commits = NULL;
3274        }
3275
3276        /*
3277         * Put all of the actual boundary commits from revs->boundary_commits
3278         * into revs->commits
3279         */
3280        for (i = 0; i < array->nr; i++) {
3281                c = (struct commit *)(objects[i].item);
3282                if (!c)
3283                        continue;
3284                if (!(c->object.flags & CHILD_SHOWN))
3285                        continue;
3286                if (c->object.flags & (SHOWN | BOUNDARY))
3287                        continue;
3288                c->object.flags |= BOUNDARY;
3289                commit_list_insert(c, &revs->commits);
3290        }
3291
3292        /*
3293         * If revs->topo_order is set, sort the boundary commits
3294         * in topological order
3295         */
3296        sort_in_topological_order(&revs->commits, revs->sort_order);
3297}
3298
3299static struct commit *get_revision_internal(struct rev_info *revs)
3300{
3301        struct commit *c = NULL;
3302        struct commit_list *l;
3303
3304        if (revs->boundary == 2) {
3305                /*
3306                 * All of the normal commits have already been returned,
3307                 * and we are now returning boundary commits.
3308                 * create_boundary_commit_list() has populated
3309                 * revs->commits with the remaining commits to return.
3310                 */
3311                c = pop_commit(&revs->commits);
3312                if (c)
3313                        c->object.flags |= SHOWN;
3314                return c;
3315        }
3316
3317        /*
3318         * If our max_count counter has reached zero, then we are done. We
3319         * don't simply return NULL because we still might need to show
3320         * boundary commits. But we want to avoid calling get_revision_1, which
3321         * might do a considerable amount of work finding the next commit only
3322         * for us to throw it away.
3323         *
3324         * If it is non-zero, then either we don't have a max_count at all
3325         * (-1), or it is still counting, in which case we decrement.
3326         */
3327        if (revs->max_count) {
3328                c = get_revision_1(revs);
3329                if (c) {
3330                        while (revs->skip_count > 0) {
3331                                revs->skip_count--;
3332                                c = get_revision_1(revs);
3333                                if (!c)
3334                                        break;
3335                        }
3336                }
3337
3338                if (revs->max_count > 0)
3339                        revs->max_count--;
3340        }
3341
3342        if (c)
3343                c->object.flags |= SHOWN;
3344
3345        if (!revs->boundary)
3346                return c;
3347
3348        if (!c) {
3349                /*
3350                 * get_revision_1() runs out the commits, and
3351                 * we are done computing the boundaries.
3352                 * switch to boundary commits output mode.
3353                 */
3354                revs->boundary = 2;
3355
3356                /*
3357                 * Update revs->commits to contain the list of
3358                 * boundary commits.
3359                 */
3360                create_boundary_commit_list(revs);
3361
3362                return get_revision_internal(revs);
3363        }
3364
3365        /*
3366         * boundary commits are the commits that are parents of the
3367         * ones we got from get_revision_1() but they themselves are
3368         * not returned from get_revision_1().  Before returning
3369         * 'c', we need to mark its parents that they could be boundaries.
3370         */
3371
3372        for (l = c->parents; l; l = l->next) {
3373                struct object *p;
3374                p = &(l->item->object);
3375                if (p->flags & (CHILD_SHOWN | SHOWN))
3376                        continue;
3377                p->flags |= CHILD_SHOWN;
3378                gc_boundary(&revs->boundary_commits);
3379                add_object_array(p, NULL, &revs->boundary_commits);
3380        }
3381
3382        return c;
3383}
3384
3385struct commit *get_revision(struct rev_info *revs)
3386{
3387        struct commit *c;
3388        struct commit_list *reversed;
3389
3390        if (revs->reverse) {
3391                reversed = NULL;
3392                while ((c = get_revision_internal(revs)))
3393                        commit_list_insert(c, &reversed);
3394                revs->commits = reversed;
3395                revs->reverse = 0;
3396                revs->reverse_output_stage = 1;
3397        }
3398
3399        if (revs->reverse_output_stage) {
3400                c = pop_commit(&revs->commits);
3401                if (revs->track_linear)
3402                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3403                return c;
3404        }
3405
3406        c = get_revision_internal(revs);
3407        if (c && revs->graph)
3408                graph_update(revs->graph, c);
3409        if (!c) {
3410                free_saved_parents(revs);
3411                if (revs->previous_parents) {
3412                        free_commit_list(revs->previous_parents);
3413                        revs->previous_parents = NULL;
3414                }
3415        }
3416        return c;
3417}
3418
3419char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3420{
3421        if (commit->object.flags & BOUNDARY)
3422                return "-";
3423        else if (commit->object.flags & UNINTERESTING)
3424                return "^";
3425        else if (commit->object.flags & PATCHSAME)
3426                return "=";
3427        else if (!revs || revs->left_right) {
3428                if (commit->object.flags & SYMMETRIC_LEFT)
3429                        return "<";
3430                else
3431                        return ">";
3432        } else if (revs->graph)
3433                return "*";
3434        else if (revs->cherry_mark)
3435                return "+";
3436        return "";
3437}
3438
3439void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3440{
3441        char *mark = get_revision_mark(revs, commit);
3442        if (!strlen(mark))
3443                return;
3444        fputs(mark, stdout);
3445        putchar(' ');
3446}