revision.con commit upload-pack: add object filtering for partial clone (10ac85c)
   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                if (revs->exclude_promisor_objects && is_promisor_object(oid))
 202                        return NULL;
 203                die("bad object %s", name);
 204        }
 205        object->flags |= flags;
 206        return object;
 207}
 208
 209void add_pending_oid(struct rev_info *revs, const char *name,
 210                      const struct object_id *oid, unsigned int flags)
 211{
 212        struct object *object = get_reference(revs, name, oid, flags);
 213        add_pending_object(revs, object, name);
 214}
 215
 216static struct commit *handle_commit(struct rev_info *revs,
 217                                    struct object_array_entry *entry)
 218{
 219        struct object *object = entry->item;
 220        const char *name = entry->name;
 221        const char *path = entry->path;
 222        unsigned int mode = entry->mode;
 223        unsigned long flags = object->flags;
 224
 225        /*
 226         * Tag object? Look what it points to..
 227         */
 228        while (object->type == OBJ_TAG) {
 229                struct tag *tag = (struct tag *) object;
 230                if (revs->tag_objects && !(flags & UNINTERESTING))
 231                        add_pending_object(revs, object, tag->tag);
 232                if (!tag->tagged)
 233                        die("bad tag");
 234                object = parse_object(&tag->tagged->oid);
 235                if (!object) {
 236                        if (revs->ignore_missing_links || (flags & UNINTERESTING))
 237                                return NULL;
 238                        die("bad object %s", oid_to_hex(&tag->tagged->oid));
 239                }
 240                object->flags |= flags;
 241                /*
 242                 * We'll handle the tagged object by looping or dropping
 243                 * through to the non-tag handlers below. Do not
 244                 * propagate path data from the tag's pending entry.
 245                 */
 246                path = NULL;
 247                mode = 0;
 248        }
 249
 250        /*
 251         * Commit object? Just return it, we'll do all the complex
 252         * reachability crud.
 253         */
 254        if (object->type == OBJ_COMMIT) {
 255                struct commit *commit = (struct commit *)object;
 256                if (parse_commit(commit) < 0)
 257                        die("unable to parse commit %s", name);
 258                if (flags & UNINTERESTING) {
 259                        mark_parents_uninteresting(commit);
 260                        revs->limited = 1;
 261                }
 262                if (revs->show_source && !commit->util)
 263                        commit->util = xstrdup(name);
 264                return commit;
 265        }
 266
 267        /*
 268         * Tree object? Either mark it uninteresting, or add it
 269         * to the list of objects to look at later..
 270         */
 271        if (object->type == OBJ_TREE) {
 272                struct tree *tree = (struct tree *)object;
 273                if (!revs->tree_objects)
 274                        return NULL;
 275                if (flags & UNINTERESTING) {
 276                        mark_tree_contents_uninteresting(tree);
 277                        return NULL;
 278                }
 279                add_pending_object_with_path(revs, object, name, mode, path);
 280                return NULL;
 281        }
 282
 283        /*
 284         * Blob object? You know the drill by now..
 285         */
 286        if (object->type == OBJ_BLOB) {
 287                if (!revs->blob_objects)
 288                        return NULL;
 289                if (flags & UNINTERESTING)
 290                        return NULL;
 291                add_pending_object_with_path(revs, object, name, mode, path);
 292                return NULL;
 293        }
 294        die("%s is unknown object", name);
 295}
 296
 297static int everybody_uninteresting(struct commit_list *orig,
 298                                   struct commit **interesting_cache)
 299{
 300        struct commit_list *list = orig;
 301
 302        if (*interesting_cache) {
 303                struct commit *commit = *interesting_cache;
 304                if (!(commit->object.flags & UNINTERESTING))
 305                        return 0;
 306        }
 307
 308        while (list) {
 309                struct commit *commit = list->item;
 310                list = list->next;
 311                if (commit->object.flags & UNINTERESTING)
 312                        continue;
 313
 314                *interesting_cache = commit;
 315                return 0;
 316        }
 317        return 1;
 318}
 319
 320/*
 321 * A definition of "relevant" commit that we can use to simplify limited graphs
 322 * by eliminating side branches.
 323 *
 324 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 325 * in our list), or that is a specified BOTTOM commit. Then after computing
 326 * a limited list, during processing we can generally ignore boundary merges
 327 * coming from outside the graph, (ie from irrelevant parents), and treat
 328 * those merges as if they were single-parent. TREESAME is defined to consider
 329 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 330 * we don't care if we were !TREESAME to non-graph parents.
 331 *
 332 * Treating bottom commits as relevant ensures that a limited graph's
 333 * connection to the actual bottom commit is not viewed as a side branch, but
 334 * treated as part of the graph. For example:
 335 *
 336 *   ....Z...A---X---o---o---B
 337 *        .     /
 338 *         W---Y
 339 *
 340 * When computing "A..B", the A-X connection is at least as important as
 341 * Y-X, despite A being flagged UNINTERESTING.
 342 *
 343 * And when computing --ancestry-path "A..B", the A-X connection is more
 344 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 345 */
 346static inline int relevant_commit(struct commit *commit)
 347{
 348        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 349}
 350
 351/*
 352 * Return a single relevant commit from a parent list. If we are a TREESAME
 353 * commit, and this selects one of our parents, then we can safely simplify to
 354 * that parent.
 355 */
 356static struct commit *one_relevant_parent(const struct rev_info *revs,
 357                                          struct commit_list *orig)
 358{
 359        struct commit_list *list = orig;
 360        struct commit *relevant = NULL;
 361
 362        if (!orig)
 363                return NULL;
 364
 365        /*
 366         * For 1-parent commits, or if first-parent-only, then return that
 367         * first parent (even if not "relevant" by the above definition).
 368         * TREESAME will have been set purely on that parent.
 369         */
 370        if (revs->first_parent_only || !orig->next)
 371                return orig->item;
 372
 373        /*
 374         * For multi-parent commits, identify a sole relevant parent, if any.
 375         * If we have only one relevant parent, then TREESAME will be set purely
 376         * with regard to that parent, and we can simplify accordingly.
 377         *
 378         * If we have more than one relevant parent, or no relevant parents
 379         * (and multiple irrelevant ones), then we can't select a parent here
 380         * and return NULL.
 381         */
 382        while (list) {
 383                struct commit *commit = list->item;
 384                list = list->next;
 385                if (relevant_commit(commit)) {
 386                        if (relevant)
 387                                return NULL;
 388                        relevant = commit;
 389                }
 390        }
 391        return relevant;
 392}
 393
 394/*
 395 * The goal is to get REV_TREE_NEW as the result only if the
 396 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 397 * if the whole diff is removal of old data, and otherwise
 398 * REV_TREE_DIFFERENT (of course if the trees are the same we
 399 * want REV_TREE_SAME).
 400 * That means that once we get to REV_TREE_DIFFERENT, we do not
 401 * have to look any further.
 402 */
 403static int tree_difference = REV_TREE_SAME;
 404
 405static void file_add_remove(struct diff_options *options,
 406                    int addremove, unsigned mode,
 407                    const struct object_id *oid,
 408                    int oid_valid,
 409                    const char *fullpath, unsigned dirty_submodule)
 410{
 411        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 412
 413        tree_difference |= diff;
 414        if (tree_difference == REV_TREE_DIFFERENT)
 415                DIFF_OPT_SET(options, HAS_CHANGES);
 416}
 417
 418static void file_change(struct diff_options *options,
 419                 unsigned old_mode, unsigned new_mode,
 420                 const struct object_id *old_oid,
 421                 const struct object_id *new_oid,
 422                 int old_oid_valid, int new_oid_valid,
 423                 const char *fullpath,
 424                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 425{
 426        tree_difference = REV_TREE_DIFFERENT;
 427        DIFF_OPT_SET(options, HAS_CHANGES);
 428}
 429
 430static int rev_compare_tree(struct rev_info *revs,
 431                            struct commit *parent, struct commit *commit)
 432{
 433        struct tree *t1 = parent->tree;
 434        struct tree *t2 = commit->tree;
 435
 436        if (!t1)
 437                return REV_TREE_NEW;
 438        if (!t2)
 439                return REV_TREE_OLD;
 440
 441        if (revs->simplify_by_decoration) {
 442                /*
 443                 * If we are simplifying by decoration, then the commit
 444                 * is worth showing if it has a tag pointing at it.
 445                 */
 446                if (get_name_decoration(&commit->object))
 447                        return REV_TREE_DIFFERENT;
 448                /*
 449                 * A commit that is not pointed by a tag is uninteresting
 450                 * if we are not limited by path.  This means that you will
 451                 * see the usual "commits that touch the paths" plus any
 452                 * tagged commit by specifying both --simplify-by-decoration
 453                 * and pathspec.
 454                 */
 455                if (!revs->prune_data.nr)
 456                        return REV_TREE_SAME;
 457        }
 458
 459        tree_difference = REV_TREE_SAME;
 460        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 461        if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
 462                           &revs->pruning) < 0)
 463                return REV_TREE_DIFFERENT;
 464        return tree_difference;
 465}
 466
 467static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 468{
 469        int retval;
 470        struct tree *t1 = commit->tree;
 471
 472        if (!t1)
 473                return 0;
 474
 475        tree_difference = REV_TREE_SAME;
 476        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 477        retval = diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);
 478
 479        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 480}
 481
 482struct treesame_state {
 483        unsigned int nparents;
 484        unsigned char treesame[FLEX_ARRAY];
 485};
 486
 487static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 488{
 489        unsigned n = commit_list_count(commit->parents);
 490        struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 491        st->nparents = n;
 492        add_decoration(&revs->treesame, &commit->object, st);
 493        return st;
 494}
 495
 496/*
 497 * Must be called immediately after removing the nth_parent from a commit's
 498 * parent list, if we are maintaining the per-parent treesame[] decoration.
 499 * This does not recalculate the master TREESAME flag - update_treesame()
 500 * should be called to update it after a sequence of treesame[] modifications
 501 * that may have affected it.
 502 */
 503static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 504{
 505        struct treesame_state *st;
 506        int old_same;
 507
 508        if (!commit->parents) {
 509                /*
 510                 * Have just removed the only parent from a non-merge.
 511                 * Different handling, as we lack decoration.
 512                 */
 513                if (nth_parent != 0)
 514                        die("compact_treesame %u", nth_parent);
 515                old_same = !!(commit->object.flags & TREESAME);
 516                if (rev_same_tree_as_empty(revs, commit))
 517                        commit->object.flags |= TREESAME;
 518                else
 519                        commit->object.flags &= ~TREESAME;
 520                return old_same;
 521        }
 522
 523        st = lookup_decoration(&revs->treesame, &commit->object);
 524        if (!st || nth_parent >= st->nparents)
 525                die("compact_treesame %u", nth_parent);
 526
 527        old_same = st->treesame[nth_parent];
 528        memmove(st->treesame + nth_parent,
 529                st->treesame + nth_parent + 1,
 530                st->nparents - nth_parent - 1);
 531
 532        /*
 533         * If we've just become a non-merge commit, update TREESAME
 534         * immediately, and remove the no-longer-needed decoration.
 535         * If still a merge, defer update until update_treesame().
 536         */
 537        if (--st->nparents == 1) {
 538                if (commit->parents->next)
 539                        die("compact_treesame parents mismatch");
 540                if (st->treesame[0] && revs->dense)
 541                        commit->object.flags |= TREESAME;
 542                else
 543                        commit->object.flags &= ~TREESAME;
 544                free(add_decoration(&revs->treesame, &commit->object, NULL));
 545        }
 546
 547        return old_same;
 548}
 549
 550static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 551{
 552        if (commit->parents && commit->parents->next) {
 553                unsigned n;
 554                struct treesame_state *st;
 555                struct commit_list *p;
 556                unsigned relevant_parents;
 557                unsigned relevant_change, irrelevant_change;
 558
 559                st = lookup_decoration(&revs->treesame, &commit->object);
 560                if (!st)
 561                        die("update_treesame %s", oid_to_hex(&commit->object.oid));
 562                relevant_parents = 0;
 563                relevant_change = irrelevant_change = 0;
 564                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 565                        if (relevant_commit(p->item)) {
 566                                relevant_change |= !st->treesame[n];
 567                                relevant_parents++;
 568                        } else
 569                                irrelevant_change |= !st->treesame[n];
 570                }
 571                if (relevant_parents ? relevant_change : irrelevant_change)
 572                        commit->object.flags &= ~TREESAME;
 573                else
 574                        commit->object.flags |= TREESAME;
 575        }
 576
 577        return commit->object.flags & TREESAME;
 578}
 579
 580static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 581{
 582        /*
 583         * TREESAME is irrelevant unless prune && dense;
 584         * if simplify_history is set, we can't have a mixture of TREESAME and
 585         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 586         *    decoration anyway);
 587         * if first_parent_only is set, then the TREESAME flag is locked
 588         *    against the first parent (and again we lack treesame[] decoration).
 589         */
 590        return revs->prune && revs->dense &&
 591               !revs->simplify_history &&
 592               !revs->first_parent_only;
 593}
 594
 595static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 596{
 597        struct commit_list **pp, *parent;
 598        struct treesame_state *ts = NULL;
 599        int relevant_change = 0, irrelevant_change = 0;
 600        int relevant_parents, nth_parent;
 601
 602        /*
 603         * If we don't do pruning, everything is interesting
 604         */
 605        if (!revs->prune)
 606                return;
 607
 608        if (!commit->tree)
 609                return;
 610
 611        if (!commit->parents) {
 612                if (rev_same_tree_as_empty(revs, commit))
 613                        commit->object.flags |= TREESAME;
 614                return;
 615        }
 616
 617        /*
 618         * Normal non-merge commit? If we don't want to make the
 619         * history dense, we consider it always to be a change..
 620         */
 621        if (!revs->dense && !commit->parents->next)
 622                return;
 623
 624        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 625             (parent = *pp) != NULL;
 626             pp = &parent->next, nth_parent++) {
 627                struct commit *p = parent->item;
 628                if (relevant_commit(p))
 629                        relevant_parents++;
 630
 631                if (nth_parent == 1) {
 632                        /*
 633                         * This our second loop iteration - so we now know
 634                         * we're dealing with a merge.
 635                         *
 636                         * Do not compare with later parents when we care only about
 637                         * the first parent chain, in order to avoid derailing the
 638                         * traversal to follow a side branch that brought everything
 639                         * in the path we are limited to by the pathspec.
 640                         */
 641                        if (revs->first_parent_only)
 642                                break;
 643                        /*
 644                         * If this will remain a potentially-simplifiable
 645                         * merge, remember per-parent treesame if needed.
 646                         * Initialise the array with the comparison from our
 647                         * first iteration.
 648                         */
 649                        if (revs->treesame.name &&
 650                            !revs->simplify_history &&
 651                            !(commit->object.flags & UNINTERESTING)) {
 652                                ts = initialise_treesame(revs, commit);
 653                                if (!(irrelevant_change || relevant_change))
 654                                        ts->treesame[0] = 1;
 655                        }
 656                }
 657                if (parse_commit(p) < 0)
 658                        die("cannot simplify commit %s (because of %s)",
 659                            oid_to_hex(&commit->object.oid),
 660                            oid_to_hex(&p->object.oid));
 661                switch (rev_compare_tree(revs, p, commit)) {
 662                case REV_TREE_SAME:
 663                        if (!revs->simplify_history || !relevant_commit(p)) {
 664                                /* Even if a merge with an uninteresting
 665                                 * side branch brought the entire change
 666                                 * we are interested in, we do not want
 667                                 * to lose the other branches of this
 668                                 * merge, so we just keep going.
 669                                 */
 670                                if (ts)
 671                                        ts->treesame[nth_parent] = 1;
 672                                continue;
 673                        }
 674                        parent->next = NULL;
 675                        commit->parents = parent;
 676                        commit->object.flags |= TREESAME;
 677                        return;
 678
 679                case REV_TREE_NEW:
 680                        if (revs->remove_empty_trees &&
 681                            rev_same_tree_as_empty(revs, p)) {
 682                                /* We are adding all the specified
 683                                 * paths from this parent, so the
 684                                 * history beyond this parent is not
 685                                 * interesting.  Remove its parents
 686                                 * (they are grandparents for us).
 687                                 * IOW, we pretend this parent is a
 688                                 * "root" commit.
 689                                 */
 690                                if (parse_commit(p) < 0)
 691                                        die("cannot simplify commit %s (invalid %s)",
 692                                            oid_to_hex(&commit->object.oid),
 693                                            oid_to_hex(&p->object.oid));
 694                                p->parents = NULL;
 695                        }
 696                /* fallthrough */
 697                case REV_TREE_OLD:
 698                case REV_TREE_DIFFERENT:
 699                        if (relevant_commit(p))
 700                                relevant_change = 1;
 701                        else
 702                                irrelevant_change = 1;
 703                        continue;
 704                }
 705                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
 706        }
 707
 708        /*
 709         * TREESAME is straightforward for single-parent commits. For merge
 710         * commits, it is most useful to define it so that "irrelevant"
 711         * parents cannot make us !TREESAME - if we have any relevant
 712         * parents, then we only consider TREESAMEness with respect to them,
 713         * allowing irrelevant merges from uninteresting branches to be
 714         * simplified away. Only if we have only irrelevant parents do we
 715         * base TREESAME on them. Note that this logic is replicated in
 716         * update_treesame, which should be kept in sync.
 717         */
 718        if (relevant_parents ? !relevant_change : !irrelevant_change)
 719                commit->object.flags |= TREESAME;
 720}
 721
 722static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 723                    struct commit_list *cached_base, struct commit_list **cache)
 724{
 725        struct commit_list *new_entry;
 726
 727        if (cached_base && p->date < cached_base->item->date)
 728                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 729        else
 730                new_entry = commit_list_insert_by_date(p, head);
 731
 732        if (cache && (!*cache || p->date < (*cache)->item->date))
 733                *cache = new_entry;
 734}
 735
 736static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 737                    struct commit_list **list, struct commit_list **cache_ptr)
 738{
 739        struct commit_list *parent = commit->parents;
 740        unsigned left_flag;
 741        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 742
 743        if (commit->object.flags & ADDED)
 744                return 0;
 745        commit->object.flags |= ADDED;
 746
 747        if (revs->include_check &&
 748            !revs->include_check(commit, revs->include_check_data))
 749                return 0;
 750
 751        /*
 752         * If the commit is uninteresting, don't try to
 753         * prune parents - we want the maximal uninteresting
 754         * set.
 755         *
 756         * Normally we haven't parsed the parent
 757         * yet, so we won't have a parent of a parent
 758         * here. However, it may turn out that we've
 759         * reached this commit some other way (where it
 760         * wasn't uninteresting), in which case we need
 761         * to mark its parents recursively too..
 762         */
 763        if (commit->object.flags & UNINTERESTING) {
 764                while (parent) {
 765                        struct commit *p = parent->item;
 766                        parent = parent->next;
 767                        if (p)
 768                                p->object.flags |= UNINTERESTING;
 769                        if (parse_commit_gently(p, 1) < 0)
 770                                continue;
 771                        if (p->parents)
 772                                mark_parents_uninteresting(p);
 773                        if (p->object.flags & SEEN)
 774                                continue;
 775                        p->object.flags |= SEEN;
 776                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 777                }
 778                return 0;
 779        }
 780
 781        /*
 782         * Ok, the commit wasn't uninteresting. Try to
 783         * simplify the commit history and find the parent
 784         * that has no differences in the path set if one exists.
 785         */
 786        try_to_simplify_commit(revs, commit);
 787
 788        if (revs->no_walk)
 789                return 0;
 790
 791        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 792
 793        for (parent = commit->parents; parent; parent = parent->next) {
 794                struct commit *p = parent->item;
 795                int gently = revs->ignore_missing_links ||
 796                             revs->exclude_promisor_objects;
 797                if (parse_commit_gently(p, gently) < 0) {
 798                        if (revs->exclude_promisor_objects &&
 799                            is_promisor_object(&p->object.oid)) {
 800                                if (revs->first_parent_only)
 801                                        break;
 802                                continue;
 803                        }
 804                        return -1;
 805                }
 806                if (revs->show_source && !p->util)
 807                        p->util = commit->util;
 808                p->object.flags |= left_flag;
 809                if (!(p->object.flags & SEEN)) {
 810                        p->object.flags |= SEEN;
 811                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 812                }
 813                if (revs->first_parent_only)
 814                        break;
 815        }
 816        return 0;
 817}
 818
 819static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 820{
 821        struct commit_list *p;
 822        int left_count = 0, right_count = 0;
 823        int left_first;
 824        struct patch_ids ids;
 825        unsigned cherry_flag;
 826
 827        /* First count the commits on the left and on the right */
 828        for (p = list; p; p = p->next) {
 829                struct commit *commit = p->item;
 830                unsigned flags = commit->object.flags;
 831                if (flags & BOUNDARY)
 832                        ;
 833                else if (flags & SYMMETRIC_LEFT)
 834                        left_count++;
 835                else
 836                        right_count++;
 837        }
 838
 839        if (!left_count || !right_count)
 840                return;
 841
 842        left_first = left_count < right_count;
 843        init_patch_ids(&ids);
 844        ids.diffopts.pathspec = revs->diffopt.pathspec;
 845
 846        /* Compute patch-ids for one side */
 847        for (p = list; p; p = p->next) {
 848                struct commit *commit = p->item;
 849                unsigned flags = commit->object.flags;
 850
 851                if (flags & BOUNDARY)
 852                        continue;
 853                /*
 854                 * If we have fewer left, left_first is set and we omit
 855                 * commits on the right branch in this loop.  If we have
 856                 * fewer right, we skip the left ones.
 857                 */
 858                if (left_first != !!(flags & SYMMETRIC_LEFT))
 859                        continue;
 860                add_commit_patch_id(commit, &ids);
 861        }
 862
 863        /* either cherry_mark or cherry_pick are true */
 864        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 865
 866        /* Check the other side */
 867        for (p = list; p; p = p->next) {
 868                struct commit *commit = p->item;
 869                struct patch_id *id;
 870                unsigned flags = commit->object.flags;
 871
 872                if (flags & BOUNDARY)
 873                        continue;
 874                /*
 875                 * If we have fewer left, left_first is set and we omit
 876                 * commits on the left branch in this loop.
 877                 */
 878                if (left_first == !!(flags & SYMMETRIC_LEFT))
 879                        continue;
 880
 881                /*
 882                 * Have we seen the same patch id?
 883                 */
 884                id = has_commit_patch_id(commit, &ids);
 885                if (!id)
 886                        continue;
 887
 888                commit->object.flags |= cherry_flag;
 889                id->commit->object.flags |= cherry_flag;
 890        }
 891
 892        free_patch_ids(&ids);
 893}
 894
 895/* How many extra uninteresting commits we want to see.. */
 896#define SLOP 5
 897
 898static int still_interesting(struct commit_list *src, timestamp_t date, int slop,
 899                             struct commit **interesting_cache)
 900{
 901        /*
 902         * No source list at all? We're definitely done..
 903         */
 904        if (!src)
 905                return 0;
 906
 907        /*
 908         * Does the destination list contain entries with a date
 909         * before the source list? Definitely _not_ done.
 910         */
 911        if (date <= src->item->date)
 912                return SLOP;
 913
 914        /*
 915         * Does the source list still have interesting commits in
 916         * it? Definitely not done..
 917         */
 918        if (!everybody_uninteresting(src, interesting_cache))
 919                return SLOP;
 920
 921        /* Ok, we're closing in.. */
 922        return slop-1;
 923}
 924
 925/*
 926 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 927 * of B but not ancestors of A but further limits the result to those
 928 * that are descendants of A.  This takes the list of bottom commits and
 929 * the result of "A..B" without --ancestry-path, and limits the latter
 930 * further to the ones that can reach one of the commits in "bottom".
 931 */
 932static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 933{
 934        struct commit_list *p;
 935        struct commit_list *rlist = NULL;
 936        int made_progress;
 937
 938        /*
 939         * Reverse the list so that it will be likely that we would
 940         * process parents before children.
 941         */
 942        for (p = list; p; p = p->next)
 943                commit_list_insert(p->item, &rlist);
 944
 945        for (p = bottom; p; p = p->next)
 946                p->item->object.flags |= TMP_MARK;
 947
 948        /*
 949         * Mark the ones that can reach bottom commits in "list",
 950         * in a bottom-up fashion.
 951         */
 952        do {
 953                made_progress = 0;
 954                for (p = rlist; p; p = p->next) {
 955                        struct commit *c = p->item;
 956                        struct commit_list *parents;
 957                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 958                                continue;
 959                        for (parents = c->parents;
 960                             parents;
 961                             parents = parents->next) {
 962                                if (!(parents->item->object.flags & TMP_MARK))
 963                                        continue;
 964                                c->object.flags |= TMP_MARK;
 965                                made_progress = 1;
 966                                break;
 967                        }
 968                }
 969        } while (made_progress);
 970
 971        /*
 972         * NEEDSWORK: decide if we want to remove parents that are
 973         * not marked with TMP_MARK from commit->parents for commits
 974         * in the resulting list.  We may not want to do that, though.
 975         */
 976
 977        /*
 978         * The ones that are not marked with TMP_MARK are uninteresting
 979         */
 980        for (p = list; p; p = p->next) {
 981                struct commit *c = p->item;
 982                if (c->object.flags & TMP_MARK)
 983                        continue;
 984                c->object.flags |= UNINTERESTING;
 985        }
 986
 987        /* We are done with the TMP_MARK */
 988        for (p = list; p; p = p->next)
 989                p->item->object.flags &= ~TMP_MARK;
 990        for (p = bottom; p; p = p->next)
 991                p->item->object.flags &= ~TMP_MARK;
 992        free_commit_list(rlist);
 993}
 994
 995/*
 996 * Before walking the history, keep the set of "negative" refs the
 997 * caller has asked to exclude.
 998 *
 999 * This is used to compute "rev-list --ancestry-path A..B", as we need
1000 * to filter the result of "A..B" further to the ones that can actually
1001 * reach A.
1002 */
1003static struct commit_list *collect_bottom_commits(struct commit_list *list)
1004{
1005        struct commit_list *elem, *bottom = NULL;
1006        for (elem = list; elem; elem = elem->next)
1007                if (elem->item->object.flags & BOTTOM)
1008                        commit_list_insert(elem->item, &bottom);
1009        return bottom;
1010}
1011
1012/* Assumes either left_only or right_only is set */
1013static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1014{
1015        struct commit_list *p;
1016
1017        for (p = list; p; p = p->next) {
1018                struct commit *commit = p->item;
1019
1020                if (revs->right_only) {
1021                        if (commit->object.flags & SYMMETRIC_LEFT)
1022                                commit->object.flags |= SHOWN;
1023                } else  /* revs->left_only is set */
1024                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1025                                commit->object.flags |= SHOWN;
1026        }
1027}
1028
1029static int limit_list(struct rev_info *revs)
1030{
1031        int slop = SLOP;
1032        timestamp_t date = TIME_MAX;
1033        struct commit_list *list = revs->commits;
1034        struct commit_list *newlist = NULL;
1035        struct commit_list **p = &newlist;
1036        struct commit_list *bottom = NULL;
1037        struct commit *interesting_cache = NULL;
1038
1039        if (revs->ancestry_path) {
1040                bottom = collect_bottom_commits(list);
1041                if (!bottom)
1042                        die("--ancestry-path given but there are no bottom commits");
1043        }
1044
1045        while (list) {
1046                struct commit *commit = pop_commit(&list);
1047                struct object *obj = &commit->object;
1048                show_early_output_fn_t show;
1049
1050                if (commit == interesting_cache)
1051                        interesting_cache = NULL;
1052
1053                if (revs->max_age != -1 && (commit->date < revs->max_age))
1054                        obj->flags |= UNINTERESTING;
1055                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1056                        return -1;
1057                if (obj->flags & UNINTERESTING) {
1058                        mark_parents_uninteresting(commit);
1059                        if (revs->show_all)
1060                                p = &commit_list_insert(commit, p)->next;
1061                        slop = still_interesting(list, date, slop, &interesting_cache);
1062                        if (slop)
1063                                continue;
1064                        /* If showing all, add the whole pending list to the end */
1065                        if (revs->show_all)
1066                                *p = list;
1067                        break;
1068                }
1069                if (revs->min_age != -1 && (commit->date > revs->min_age))
1070                        continue;
1071                date = commit->date;
1072                p = &commit_list_insert(commit, p)->next;
1073
1074                show = show_early_output;
1075                if (!show)
1076                        continue;
1077
1078                show(revs, newlist);
1079                show_early_output = NULL;
1080        }
1081        if (revs->cherry_pick || revs->cherry_mark)
1082                cherry_pick_list(newlist, revs);
1083
1084        if (revs->left_only || revs->right_only)
1085                limit_left_right(newlist, revs);
1086
1087        if (bottom) {
1088                limit_to_ancestry(bottom, newlist);
1089                free_commit_list(bottom);
1090        }
1091
1092        /*
1093         * Check if any commits have become TREESAME by some of their parents
1094         * becoming UNINTERESTING.
1095         */
1096        if (limiting_can_increase_treesame(revs))
1097                for (list = newlist; list; list = list->next) {
1098                        struct commit *c = list->item;
1099                        if (c->object.flags & (UNINTERESTING | TREESAME))
1100                                continue;
1101                        update_treesame(revs, c);
1102                }
1103
1104        revs->commits = newlist;
1105        return 0;
1106}
1107
1108/*
1109 * Add an entry to refs->cmdline with the specified information.
1110 * *name is copied.
1111 */
1112static void add_rev_cmdline(struct rev_info *revs,
1113                            struct object *item,
1114                            const char *name,
1115                            int whence,
1116                            unsigned flags)
1117{
1118        struct rev_cmdline_info *info = &revs->cmdline;
1119        unsigned int nr = info->nr;
1120
1121        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1122        info->rev[nr].item = item;
1123        info->rev[nr].name = xstrdup(name);
1124        info->rev[nr].whence = whence;
1125        info->rev[nr].flags = flags;
1126        info->nr++;
1127}
1128
1129static void add_rev_cmdline_list(struct rev_info *revs,
1130                                 struct commit_list *commit_list,
1131                                 int whence,
1132                                 unsigned flags)
1133{
1134        while (commit_list) {
1135                struct object *object = &commit_list->item->object;
1136                add_rev_cmdline(revs, object, oid_to_hex(&object->oid),
1137                                whence, flags);
1138                commit_list = commit_list->next;
1139        }
1140}
1141
1142struct all_refs_cb {
1143        int all_flags;
1144        int warned_bad_reflog;
1145        struct rev_info *all_revs;
1146        const char *name_for_errormsg;
1147        struct ref_store *refs;
1148};
1149
1150int ref_excluded(struct string_list *ref_excludes, const char *path)
1151{
1152        struct string_list_item *item;
1153
1154        if (!ref_excludes)
1155                return 0;
1156        for_each_string_list_item(item, ref_excludes) {
1157                if (!wildmatch(item->string, path, 0))
1158                        return 1;
1159        }
1160        return 0;
1161}
1162
1163static int handle_one_ref(const char *path, const struct object_id *oid,
1164                          int flag, void *cb_data)
1165{
1166        struct all_refs_cb *cb = cb_data;
1167        struct object *object;
1168
1169        if (ref_excluded(cb->all_revs->ref_excludes, path))
1170            return 0;
1171
1172        object = get_reference(cb->all_revs, path, oid, cb->all_flags);
1173        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1174        add_pending_oid(cb->all_revs, path, oid, cb->all_flags);
1175        return 0;
1176}
1177
1178static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1179        unsigned flags)
1180{
1181        cb->all_revs = revs;
1182        cb->all_flags = flags;
1183        revs->rev_input_given = 1;
1184        cb->refs = NULL;
1185}
1186
1187void clear_ref_exclusion(struct string_list **ref_excludes_p)
1188{
1189        if (*ref_excludes_p) {
1190                string_list_clear(*ref_excludes_p, 0);
1191                free(*ref_excludes_p);
1192        }
1193        *ref_excludes_p = NULL;
1194}
1195
1196void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1197{
1198        if (!*ref_excludes_p) {
1199                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1200                (*ref_excludes_p)->strdup_strings = 1;
1201        }
1202        string_list_append(*ref_excludes_p, exclude);
1203}
1204
1205static void handle_refs(struct ref_store *refs,
1206                        struct rev_info *revs, unsigned flags,
1207                        int (*for_each)(struct ref_store *, each_ref_fn, void *))
1208{
1209        struct all_refs_cb cb;
1210
1211        if (!refs) {
1212                /* this could happen with uninitialized submodules */
1213                return;
1214        }
1215
1216        init_all_refs_cb(&cb, revs, flags);
1217        for_each(refs, handle_one_ref, &cb);
1218}
1219
1220static void handle_one_reflog_commit(struct object_id *oid, void *cb_data)
1221{
1222        struct all_refs_cb *cb = cb_data;
1223        if (!is_null_oid(oid)) {
1224                struct object *o = parse_object(oid);
1225                if (o) {
1226                        o->flags |= cb->all_flags;
1227                        /* ??? CMDLINEFLAGS ??? */
1228                        add_pending_object(cb->all_revs, o, "");
1229                }
1230                else if (!cb->warned_bad_reflog) {
1231                        warning("reflog of '%s' references pruned commits",
1232                                cb->name_for_errormsg);
1233                        cb->warned_bad_reflog = 1;
1234                }
1235        }
1236}
1237
1238static int handle_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
1239                const char *email, timestamp_t timestamp, int tz,
1240                const char *message, void *cb_data)
1241{
1242        handle_one_reflog_commit(ooid, cb_data);
1243        handle_one_reflog_commit(noid, cb_data);
1244        return 0;
1245}
1246
1247static int handle_one_reflog(const char *path, const struct object_id *oid,
1248                             int flag, void *cb_data)
1249{
1250        struct all_refs_cb *cb = cb_data;
1251        cb->warned_bad_reflog = 0;
1252        cb->name_for_errormsg = path;
1253        refs_for_each_reflog_ent(cb->refs, path,
1254                                 handle_one_reflog_ent, cb_data);
1255        return 0;
1256}
1257
1258static void add_other_reflogs_to_pending(struct all_refs_cb *cb)
1259{
1260        struct worktree **worktrees, **p;
1261
1262        worktrees = get_worktrees(0);
1263        for (p = worktrees; *p; p++) {
1264                struct worktree *wt = *p;
1265
1266                if (wt->is_current)
1267                        continue;
1268
1269                cb->refs = get_worktree_ref_store(wt);
1270                refs_for_each_reflog(cb->refs,
1271                                     handle_one_reflog,
1272                                     cb);
1273        }
1274        free_worktrees(worktrees);
1275}
1276
1277void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1278{
1279        struct all_refs_cb cb;
1280
1281        cb.all_revs = revs;
1282        cb.all_flags = flags;
1283        cb.refs = get_main_ref_store();
1284        for_each_reflog(handle_one_reflog, &cb);
1285
1286        if (!revs->single_worktree)
1287                add_other_reflogs_to_pending(&cb);
1288}
1289
1290static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1291                           struct strbuf *path)
1292{
1293        size_t baselen = path->len;
1294        int i;
1295
1296        if (it->entry_count >= 0) {
1297                struct tree *tree = lookup_tree(&it->oid);
1298                add_pending_object_with_path(revs, &tree->object, "",
1299                                             040000, path->buf);
1300        }
1301
1302        for (i = 0; i < it->subtree_nr; i++) {
1303                struct cache_tree_sub *sub = it->down[i];
1304                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1305                add_cache_tree(sub->cache_tree, revs, path);
1306                strbuf_setlen(path, baselen);
1307        }
1308
1309}
1310
1311static void do_add_index_objects_to_pending(struct rev_info *revs,
1312                                            struct index_state *istate)
1313{
1314        int i;
1315
1316        for (i = 0; i < istate->cache_nr; i++) {
1317                struct cache_entry *ce = istate->cache[i];
1318                struct blob *blob;
1319
1320                if (S_ISGITLINK(ce->ce_mode))
1321                        continue;
1322
1323                blob = lookup_blob(&ce->oid);
1324                if (!blob)
1325                        die("unable to add index blob to traversal");
1326                add_pending_object_with_path(revs, &blob->object, "",
1327                                             ce->ce_mode, ce->name);
1328        }
1329
1330        if (istate->cache_tree) {
1331                struct strbuf path = STRBUF_INIT;
1332                add_cache_tree(istate->cache_tree, revs, &path);
1333                strbuf_release(&path);
1334        }
1335}
1336
1337void add_index_objects_to_pending(struct rev_info *revs, unsigned int flags)
1338{
1339        struct worktree **worktrees, **p;
1340
1341        read_cache();
1342        do_add_index_objects_to_pending(revs, &the_index);
1343
1344        if (revs->single_worktree)
1345                return;
1346
1347        worktrees = get_worktrees(0);
1348        for (p = worktrees; *p; p++) {
1349                struct worktree *wt = *p;
1350                struct index_state istate = { NULL };
1351
1352                if (wt->is_current)
1353                        continue; /* current index already taken care of */
1354
1355                if (read_index_from(&istate,
1356                                    worktree_git_path(wt, "index")) > 0)
1357                        do_add_index_objects_to_pending(revs, &istate);
1358                discard_index(&istate);
1359        }
1360        free_worktrees(worktrees);
1361}
1362
1363static int add_parents_only(struct rev_info *revs, const char *arg_, int flags,
1364                            int exclude_parent)
1365{
1366        struct object_id oid;
1367        struct object *it;
1368        struct commit *commit;
1369        struct commit_list *parents;
1370        int parent_number;
1371        const char *arg = arg_;
1372
1373        if (*arg == '^') {
1374                flags ^= UNINTERESTING | BOTTOM;
1375                arg++;
1376        }
1377        if (get_oid_committish(arg, &oid))
1378                return 0;
1379        while (1) {
1380                it = get_reference(revs, arg, &oid, 0);
1381                if (!it && revs->ignore_missing)
1382                        return 0;
1383                if (it->type != OBJ_TAG)
1384                        break;
1385                if (!((struct tag*)it)->tagged)
1386                        return 0;
1387                oidcpy(&oid, &((struct tag*)it)->tagged->oid);
1388        }
1389        if (it->type != OBJ_COMMIT)
1390                return 0;
1391        commit = (struct commit *)it;
1392        if (exclude_parent &&
1393            exclude_parent > commit_list_count(commit->parents))
1394                return 0;
1395        for (parents = commit->parents, parent_number = 1;
1396             parents;
1397             parents = parents->next, parent_number++) {
1398                if (exclude_parent && parent_number != exclude_parent)
1399                        continue;
1400
1401                it = &parents->item->object;
1402                it->flags |= flags;
1403                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1404                add_pending_object(revs, it, arg);
1405        }
1406        return 1;
1407}
1408
1409void init_revisions(struct rev_info *revs, const char *prefix)
1410{
1411        memset(revs, 0, sizeof(*revs));
1412
1413        revs->abbrev = DEFAULT_ABBREV;
1414        revs->ignore_merges = 1;
1415        revs->simplify_history = 1;
1416        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
1417        DIFF_OPT_SET(&revs->pruning, QUICK);
1418        revs->pruning.add_remove = file_add_remove;
1419        revs->pruning.change = file_change;
1420        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1421        revs->dense = 1;
1422        revs->prefix = prefix;
1423        revs->max_age = -1;
1424        revs->min_age = -1;
1425        revs->skip_count = -1;
1426        revs->max_count = -1;
1427        revs->max_parents = -1;
1428        revs->expand_tabs_in_log = -1;
1429
1430        revs->commit_format = CMIT_FMT_DEFAULT;
1431        revs->expand_tabs_in_log_default = 8;
1432
1433        init_grep_defaults();
1434        grep_init(&revs->grep_filter, prefix);
1435        revs->grep_filter.status_only = 1;
1436
1437        diff_setup(&revs->diffopt);
1438        if (prefix && !revs->diffopt.prefix) {
1439                revs->diffopt.prefix = prefix;
1440                revs->diffopt.prefix_length = strlen(prefix);
1441        }
1442
1443        revs->notes_opt.use_default_notes = -1;
1444}
1445
1446static void add_pending_commit_list(struct rev_info *revs,
1447                                    struct commit_list *commit_list,
1448                                    unsigned int flags)
1449{
1450        while (commit_list) {
1451                struct object *object = &commit_list->item->object;
1452                object->flags |= flags;
1453                add_pending_object(revs, object, oid_to_hex(&object->oid));
1454                commit_list = commit_list->next;
1455        }
1456}
1457
1458static void prepare_show_merge(struct rev_info *revs)
1459{
1460        struct commit_list *bases;
1461        struct commit *head, *other;
1462        struct object_id oid;
1463        const char **prune = NULL;
1464        int i, prune_num = 1; /* counting terminating NULL */
1465
1466        if (get_oid("HEAD", &oid))
1467                die("--merge without HEAD?");
1468        head = lookup_commit_or_die(&oid, "HEAD");
1469        if (get_oid("MERGE_HEAD", &oid))
1470                die("--merge without MERGE_HEAD?");
1471        other = lookup_commit_or_die(&oid, "MERGE_HEAD");
1472        add_pending_object(revs, &head->object, "HEAD");
1473        add_pending_object(revs, &other->object, "MERGE_HEAD");
1474        bases = get_merge_bases(head, other);
1475        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1476        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1477        free_commit_list(bases);
1478        head->object.flags |= SYMMETRIC_LEFT;
1479
1480        if (!active_nr)
1481                read_cache();
1482        for (i = 0; i < active_nr; i++) {
1483                const struct cache_entry *ce = active_cache[i];
1484                if (!ce_stage(ce))
1485                        continue;
1486                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1487                        prune_num++;
1488                        REALLOC_ARRAY(prune, prune_num);
1489                        prune[prune_num-2] = ce->name;
1490                        prune[prune_num-1] = NULL;
1491                }
1492                while ((i+1 < active_nr) &&
1493                       ce_same_name(ce, active_cache[i+1]))
1494                        i++;
1495        }
1496        clear_pathspec(&revs->prune_data);
1497        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1498                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1499        revs->limited = 1;
1500}
1501
1502static int dotdot_missing(const char *arg, char *dotdot,
1503                          struct rev_info *revs, int symmetric)
1504{
1505        if (revs->ignore_missing)
1506                return 0;
1507        /* de-munge so we report the full argument */
1508        *dotdot = '.';
1509        die(symmetric
1510            ? "Invalid symmetric difference expression %s"
1511            : "Invalid revision range %s", arg);
1512}
1513
1514static int handle_dotdot_1(const char *arg, char *dotdot,
1515                           struct rev_info *revs, int flags,
1516                           int cant_be_filename,
1517                           struct object_context *a_oc,
1518                           struct object_context *b_oc)
1519{
1520        const char *a_name, *b_name;
1521        struct object_id a_oid, b_oid;
1522        struct object *a_obj, *b_obj;
1523        unsigned int a_flags, b_flags;
1524        int symmetric = 0;
1525        unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1526        unsigned int oc_flags = GET_OID_COMMITTISH | GET_OID_RECORD_PATH;
1527
1528        a_name = arg;
1529        if (!*a_name)
1530                a_name = "HEAD";
1531
1532        b_name = dotdot + 2;
1533        if (*b_name == '.') {
1534                symmetric = 1;
1535                b_name++;
1536        }
1537        if (!*b_name)
1538                b_name = "HEAD";
1539
1540        if (get_oid_with_context(a_name, oc_flags, &a_oid, a_oc) ||
1541            get_oid_with_context(b_name, oc_flags, &b_oid, b_oc))
1542                return -1;
1543
1544        if (!cant_be_filename) {
1545                *dotdot = '.';
1546                verify_non_filename(revs->prefix, arg);
1547                *dotdot = '\0';
1548        }
1549
1550        a_obj = parse_object(&a_oid);
1551        b_obj = parse_object(&b_oid);
1552        if (!a_obj || !b_obj)
1553                return dotdot_missing(arg, dotdot, revs, symmetric);
1554
1555        if (!symmetric) {
1556                /* just A..B */
1557                b_flags = flags;
1558                a_flags = flags_exclude;
1559        } else {
1560                /* A...B -- find merge bases between the two */
1561                struct commit *a, *b;
1562                struct commit_list *exclude;
1563
1564                a = lookup_commit_reference(&a_obj->oid);
1565                b = lookup_commit_reference(&b_obj->oid);
1566                if (!a || !b)
1567                        return dotdot_missing(arg, dotdot, revs, symmetric);
1568
1569                exclude = get_merge_bases(a, b);
1570                add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
1571                                     flags_exclude);
1572                add_pending_commit_list(revs, exclude, flags_exclude);
1573                free_commit_list(exclude);
1574
1575                b_flags = flags;
1576                a_flags = flags | SYMMETRIC_LEFT;
1577        }
1578
1579        a_obj->flags |= a_flags;
1580        b_obj->flags |= b_flags;
1581        add_rev_cmdline(revs, a_obj, a_name, REV_CMD_LEFT, a_flags);
1582        add_rev_cmdline(revs, b_obj, b_name, REV_CMD_RIGHT, b_flags);
1583        add_pending_object_with_path(revs, a_obj, a_name, a_oc->mode, a_oc->path);
1584        add_pending_object_with_path(revs, b_obj, b_name, b_oc->mode, b_oc->path);
1585        return 0;
1586}
1587
1588static int handle_dotdot(const char *arg,
1589                         struct rev_info *revs, int flags,
1590                         int cant_be_filename)
1591{
1592        struct object_context a_oc, b_oc;
1593        char *dotdot = strstr(arg, "..");
1594        int ret;
1595
1596        if (!dotdot)
1597                return -1;
1598
1599        memset(&a_oc, 0, sizeof(a_oc));
1600        memset(&b_oc, 0, sizeof(b_oc));
1601
1602        *dotdot = '\0';
1603        ret = handle_dotdot_1(arg, dotdot, revs, flags, cant_be_filename,
1604                              &a_oc, &b_oc);
1605        *dotdot = '.';
1606
1607        free(a_oc.path);
1608        free(b_oc.path);
1609
1610        return ret;
1611}
1612
1613int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1614{
1615        struct object_context oc;
1616        char *mark;
1617        struct object *object;
1618        struct object_id oid;
1619        int local_flags;
1620        const char *arg = arg_;
1621        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1622        unsigned get_sha1_flags = GET_OID_RECORD_PATH;
1623
1624        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1625
1626        if (!cant_be_filename && !strcmp(arg, "..")) {
1627                /*
1628                 * Just ".."?  That is not a range but the
1629                 * pathspec for the parent directory.
1630                 */
1631                return -1;
1632        }
1633
1634        if (!handle_dotdot(arg, revs, flags, revarg_opt))
1635                return 0;
1636
1637        mark = strstr(arg, "^@");
1638        if (mark && !mark[2]) {
1639                *mark = 0;
1640                if (add_parents_only(revs, arg, flags, 0))
1641                        return 0;
1642                *mark = '^';
1643        }
1644        mark = strstr(arg, "^!");
1645        if (mark && !mark[2]) {
1646                *mark = 0;
1647                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), 0))
1648                        *mark = '^';
1649        }
1650        mark = strstr(arg, "^-");
1651        if (mark) {
1652                int exclude_parent = 1;
1653
1654                if (mark[2]) {
1655                        char *end;
1656                        exclude_parent = strtoul(mark + 2, &end, 10);
1657                        if (*end != '\0' || !exclude_parent)
1658                                return -1;
1659                }
1660
1661                *mark = 0;
1662                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), exclude_parent))
1663                        *mark = '^';
1664        }
1665
1666        local_flags = 0;
1667        if (*arg == '^') {
1668                local_flags = UNINTERESTING | BOTTOM;
1669                arg++;
1670        }
1671
1672        if (revarg_opt & REVARG_COMMITTISH)
1673                get_sha1_flags |= GET_OID_COMMITTISH;
1674
1675        if (get_oid_with_context(arg, get_sha1_flags, &oid, &oc))
1676                return revs->ignore_missing ? 0 : -1;
1677        if (!cant_be_filename)
1678                verify_non_filename(revs->prefix, arg);
1679        object = get_reference(revs, arg, &oid, flags ^ local_flags);
1680        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1681        add_pending_object_with_path(revs, object, arg, oc.mode, oc.path);
1682        free(oc.path);
1683        return 0;
1684}
1685
1686static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1687                                     struct argv_array *prune)
1688{
1689        while (strbuf_getline(sb, stdin) != EOF)
1690                argv_array_push(prune, sb->buf);
1691}
1692
1693static void read_revisions_from_stdin(struct rev_info *revs,
1694                                      struct argv_array *prune)
1695{
1696        struct strbuf sb;
1697        int seen_dashdash = 0;
1698        int save_warning;
1699
1700        save_warning = warn_on_object_refname_ambiguity;
1701        warn_on_object_refname_ambiguity = 0;
1702
1703        strbuf_init(&sb, 1000);
1704        while (strbuf_getline(&sb, stdin) != EOF) {
1705                int len = sb.len;
1706                if (!len)
1707                        break;
1708                if (sb.buf[0] == '-') {
1709                        if (len == 2 && sb.buf[1] == '-') {
1710                                seen_dashdash = 1;
1711                                break;
1712                        }
1713                        die("options not supported in --stdin mode");
1714                }
1715                if (handle_revision_arg(sb.buf, revs, 0,
1716                                        REVARG_CANNOT_BE_FILENAME))
1717                        die("bad revision '%s'", sb.buf);
1718        }
1719        if (seen_dashdash)
1720                read_pathspec_from_stdin(revs, &sb, prune);
1721
1722        strbuf_release(&sb);
1723        warn_on_object_refname_ambiguity = save_warning;
1724}
1725
1726static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1727{
1728        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1729}
1730
1731static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1732{
1733        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1734}
1735
1736static void add_message_grep(struct rev_info *revs, const char *pattern)
1737{
1738        add_grep(revs, pattern, GREP_PATTERN_BODY);
1739}
1740
1741static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1742                               int *unkc, const char **unkv)
1743{
1744        const char *arg = argv[0];
1745        const char *optarg;
1746        int argcount;
1747
1748        /* pseudo revision arguments */
1749        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1750            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1751            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1752            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1753            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1754            !strcmp(arg, "--indexed-objects") ||
1755            starts_with(arg, "--exclude=") ||
1756            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1757            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1758        {
1759                unkv[(*unkc)++] = arg;
1760                return 1;
1761        }
1762
1763        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1764                revs->max_count = atoi(optarg);
1765                revs->no_walk = 0;
1766                return argcount;
1767        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1768                revs->skip_count = atoi(optarg);
1769                return argcount;
1770        } else if ((*arg == '-') && isdigit(arg[1])) {
1771                /* accept -<digit>, like traditional "head" */
1772                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1773                    revs->max_count < 0)
1774                        die("'%s': not a non-negative integer", arg + 1);
1775                revs->no_walk = 0;
1776        } else if (!strcmp(arg, "-n")) {
1777                if (argc <= 1)
1778                        return error("-n requires an argument");
1779                revs->max_count = atoi(argv[1]);
1780                revs->no_walk = 0;
1781                return 2;
1782        } else if (skip_prefix(arg, "-n", &optarg)) {
1783                revs->max_count = atoi(optarg);
1784                revs->no_walk = 0;
1785        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1786                revs->max_age = atoi(optarg);
1787                return argcount;
1788        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1789                revs->max_age = approxidate(optarg);
1790                return argcount;
1791        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1792                revs->max_age = approxidate(optarg);
1793                return argcount;
1794        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1795                revs->min_age = atoi(optarg);
1796                return argcount;
1797        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1798                revs->min_age = approxidate(optarg);
1799                return argcount;
1800        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1801                revs->min_age = approxidate(optarg);
1802                return argcount;
1803        } else if (!strcmp(arg, "--first-parent")) {
1804                revs->first_parent_only = 1;
1805        } else if (!strcmp(arg, "--ancestry-path")) {
1806                revs->ancestry_path = 1;
1807                revs->simplify_history = 0;
1808                revs->limited = 1;
1809        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1810                init_reflog_walk(&revs->reflog_info);
1811        } else if (!strcmp(arg, "--default")) {
1812                if (argc <= 1)
1813                        return error("bad --default argument");
1814                revs->def = argv[1];
1815                return 2;
1816        } else if (!strcmp(arg, "--merge")) {
1817                revs->show_merge = 1;
1818        } else if (!strcmp(arg, "--topo-order")) {
1819                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1820                revs->topo_order = 1;
1821        } else if (!strcmp(arg, "--simplify-merges")) {
1822                revs->simplify_merges = 1;
1823                revs->topo_order = 1;
1824                revs->rewrite_parents = 1;
1825                revs->simplify_history = 0;
1826                revs->limited = 1;
1827        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1828                revs->simplify_merges = 1;
1829                revs->topo_order = 1;
1830                revs->rewrite_parents = 1;
1831                revs->simplify_history = 0;
1832                revs->simplify_by_decoration = 1;
1833                revs->limited = 1;
1834                revs->prune = 1;
1835                load_ref_decorations(DECORATE_SHORT_REFS);
1836        } else if (!strcmp(arg, "--date-order")) {
1837                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1838                revs->topo_order = 1;
1839        } else if (!strcmp(arg, "--author-date-order")) {
1840                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1841                revs->topo_order = 1;
1842        } else if (!strcmp(arg, "--early-output")) {
1843                revs->early_output = 100;
1844                revs->topo_order = 1;
1845        } else if (skip_prefix(arg, "--early-output=", &optarg)) {
1846                if (strtoul_ui(optarg, 10, &revs->early_output) < 0)
1847                        die("'%s': not a non-negative integer", optarg);
1848                revs->topo_order = 1;
1849        } else if (!strcmp(arg, "--parents")) {
1850                revs->rewrite_parents = 1;
1851                revs->print_parents = 1;
1852        } else if (!strcmp(arg, "--dense")) {
1853                revs->dense = 1;
1854        } else if (!strcmp(arg, "--sparse")) {
1855                revs->dense = 0;
1856        } else if (!strcmp(arg, "--show-all")) {
1857                revs->show_all = 1;
1858        } else if (!strcmp(arg, "--remove-empty")) {
1859                revs->remove_empty_trees = 1;
1860        } else if (!strcmp(arg, "--merges")) {
1861                revs->min_parents = 2;
1862        } else if (!strcmp(arg, "--no-merges")) {
1863                revs->max_parents = 1;
1864        } else if (skip_prefix(arg, "--min-parents=", &optarg)) {
1865                revs->min_parents = atoi(optarg);
1866        } else if (!strcmp(arg, "--no-min-parents")) {
1867                revs->min_parents = 0;
1868        } else if (skip_prefix(arg, "--max-parents=", &optarg)) {
1869                revs->max_parents = atoi(optarg);
1870        } else if (!strcmp(arg, "--no-max-parents")) {
1871                revs->max_parents = -1;
1872        } else if (!strcmp(arg, "--boundary")) {
1873                revs->boundary = 1;
1874        } else if (!strcmp(arg, "--left-right")) {
1875                revs->left_right = 1;
1876        } else if (!strcmp(arg, "--left-only")) {
1877                if (revs->right_only)
1878                        die("--left-only is incompatible with --right-only"
1879                            " or --cherry");
1880                revs->left_only = 1;
1881        } else if (!strcmp(arg, "--right-only")) {
1882                if (revs->left_only)
1883                        die("--right-only is incompatible with --left-only");
1884                revs->right_only = 1;
1885        } else if (!strcmp(arg, "--cherry")) {
1886                if (revs->left_only)
1887                        die("--cherry is incompatible with --left-only");
1888                revs->cherry_mark = 1;
1889                revs->right_only = 1;
1890                revs->max_parents = 1;
1891                revs->limited = 1;
1892        } else if (!strcmp(arg, "--count")) {
1893                revs->count = 1;
1894        } else if (!strcmp(arg, "--cherry-mark")) {
1895                if (revs->cherry_pick)
1896                        die("--cherry-mark is incompatible with --cherry-pick");
1897                revs->cherry_mark = 1;
1898                revs->limited = 1; /* needs limit_list() */
1899        } else if (!strcmp(arg, "--cherry-pick")) {
1900                if (revs->cherry_mark)
1901                        die("--cherry-pick is incompatible with --cherry-mark");
1902                revs->cherry_pick = 1;
1903                revs->limited = 1;
1904        } else if (!strcmp(arg, "--objects")) {
1905                revs->tag_objects = 1;
1906                revs->tree_objects = 1;
1907                revs->blob_objects = 1;
1908        } else if (!strcmp(arg, "--objects-edge")) {
1909                revs->tag_objects = 1;
1910                revs->tree_objects = 1;
1911                revs->blob_objects = 1;
1912                revs->edge_hint = 1;
1913        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1914                revs->tag_objects = 1;
1915                revs->tree_objects = 1;
1916                revs->blob_objects = 1;
1917                revs->edge_hint = 1;
1918                revs->edge_hint_aggressive = 1;
1919        } else if (!strcmp(arg, "--verify-objects")) {
1920                revs->tag_objects = 1;
1921                revs->tree_objects = 1;
1922                revs->blob_objects = 1;
1923                revs->verify_objects = 1;
1924        } else if (!strcmp(arg, "--unpacked")) {
1925                revs->unpacked = 1;
1926        } else if (starts_with(arg, "--unpacked=")) {
1927                die("--unpacked=<packfile> no longer supported.");
1928        } else if (!strcmp(arg, "-r")) {
1929                revs->diff = 1;
1930                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1931        } else if (!strcmp(arg, "-t")) {
1932                revs->diff = 1;
1933                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1934                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1935        } else if (!strcmp(arg, "-m")) {
1936                revs->ignore_merges = 0;
1937        } else if (!strcmp(arg, "-c")) {
1938                revs->diff = 1;
1939                revs->dense_combined_merges = 0;
1940                revs->combine_merges = 1;
1941        } else if (!strcmp(arg, "--cc")) {
1942                revs->diff = 1;
1943                revs->dense_combined_merges = 1;
1944                revs->combine_merges = 1;
1945        } else if (!strcmp(arg, "-v")) {
1946                revs->verbose_header = 1;
1947        } else if (!strcmp(arg, "--pretty")) {
1948                revs->verbose_header = 1;
1949                revs->pretty_given = 1;
1950                get_commit_format(NULL, revs);
1951        } else if (skip_prefix(arg, "--pretty=", &optarg) ||
1952                   skip_prefix(arg, "--format=", &optarg)) {
1953                /*
1954                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1955                 * not allowed, since the argument is optional.
1956                 */
1957                revs->verbose_header = 1;
1958                revs->pretty_given = 1;
1959                get_commit_format(optarg, revs);
1960        } else if (!strcmp(arg, "--expand-tabs")) {
1961                revs->expand_tabs_in_log = 8;
1962        } else if (!strcmp(arg, "--no-expand-tabs")) {
1963                revs->expand_tabs_in_log = 0;
1964        } else if (skip_prefix(arg, "--expand-tabs=", &arg)) {
1965                int val;
1966                if (strtol_i(arg, 10, &val) < 0 || val < 0)
1967                        die("'%s': not a non-negative integer", arg);
1968                revs->expand_tabs_in_log = val;
1969        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1970                revs->show_notes = 1;
1971                revs->show_notes_given = 1;
1972                revs->notes_opt.use_default_notes = 1;
1973        } else if (!strcmp(arg, "--show-signature")) {
1974                revs->show_signature = 1;
1975        } else if (!strcmp(arg, "--no-show-signature")) {
1976                revs->show_signature = 0;
1977        } else if (!strcmp(arg, "--show-linear-break")) {
1978                revs->break_bar = "                    ..........";
1979                revs->track_linear = 1;
1980                revs->track_first_time = 1;
1981        } else if (skip_prefix(arg, "--show-linear-break=", &optarg)) {
1982                revs->break_bar = xstrdup(optarg);
1983                revs->track_linear = 1;
1984                revs->track_first_time = 1;
1985        } else if (skip_prefix(arg, "--show-notes=", &optarg) ||
1986                   skip_prefix(arg, "--notes=", &optarg)) {
1987                struct strbuf buf = STRBUF_INIT;
1988                revs->show_notes = 1;
1989                revs->show_notes_given = 1;
1990                if (starts_with(arg, "--show-notes=") &&
1991                    revs->notes_opt.use_default_notes < 0)
1992                        revs->notes_opt.use_default_notes = 1;
1993                strbuf_addstr(&buf, optarg);
1994                expand_notes_ref(&buf);
1995                string_list_append(&revs->notes_opt.extra_notes_refs,
1996                                   strbuf_detach(&buf, NULL));
1997        } else if (!strcmp(arg, "--no-notes")) {
1998                revs->show_notes = 0;
1999                revs->show_notes_given = 1;
2000                revs->notes_opt.use_default_notes = -1;
2001                /* we have been strdup'ing ourselves, so trick
2002                 * string_list into free()ing strings */
2003                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
2004                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
2005                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
2006        } else if (!strcmp(arg, "--standard-notes")) {
2007                revs->show_notes_given = 1;
2008                revs->notes_opt.use_default_notes = 1;
2009        } else if (!strcmp(arg, "--no-standard-notes")) {
2010                revs->notes_opt.use_default_notes = 0;
2011        } else if (!strcmp(arg, "--oneline")) {
2012                revs->verbose_header = 1;
2013                get_commit_format("oneline", revs);
2014                revs->pretty_given = 1;
2015                revs->abbrev_commit = 1;
2016        } else if (!strcmp(arg, "--graph")) {
2017                revs->topo_order = 1;
2018                revs->rewrite_parents = 1;
2019                revs->graph = graph_init(revs);
2020        } else if (!strcmp(arg, "--root")) {
2021                revs->show_root_diff = 1;
2022        } else if (!strcmp(arg, "--no-commit-id")) {
2023                revs->no_commit_id = 1;
2024        } else if (!strcmp(arg, "--always")) {
2025                revs->always_show_header = 1;
2026        } else if (!strcmp(arg, "--no-abbrev")) {
2027                revs->abbrev = 0;
2028        } else if (!strcmp(arg, "--abbrev")) {
2029                revs->abbrev = DEFAULT_ABBREV;
2030        } else if (skip_prefix(arg, "--abbrev=", &optarg)) {
2031                revs->abbrev = strtoul(optarg, NULL, 10);
2032                if (revs->abbrev < MINIMUM_ABBREV)
2033                        revs->abbrev = MINIMUM_ABBREV;
2034                else if (revs->abbrev > 40)
2035                        revs->abbrev = 40;
2036        } else if (!strcmp(arg, "--abbrev-commit")) {
2037                revs->abbrev_commit = 1;
2038                revs->abbrev_commit_given = 1;
2039        } else if (!strcmp(arg, "--no-abbrev-commit")) {
2040                revs->abbrev_commit = 0;
2041        } else if (!strcmp(arg, "--full-diff")) {
2042                revs->diff = 1;
2043                revs->full_diff = 1;
2044        } else if (!strcmp(arg, "--full-history")) {
2045                revs->simplify_history = 0;
2046        } else if (!strcmp(arg, "--relative-date")) {
2047                revs->date_mode.type = DATE_RELATIVE;
2048                revs->date_mode_explicit = 1;
2049        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
2050                parse_date_format(optarg, &revs->date_mode);
2051                revs->date_mode_explicit = 1;
2052                return argcount;
2053        } else if (!strcmp(arg, "--log-size")) {
2054                revs->show_log_size = 1;
2055        }
2056        /*
2057         * Grepping the commit log
2058         */
2059        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
2060                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
2061                return argcount;
2062        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
2063                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
2064                return argcount;
2065        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
2066                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
2067                return argcount;
2068        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
2069                add_message_grep(revs, optarg);
2070                return argcount;
2071        } else if (!strcmp(arg, "--grep-debug")) {
2072                revs->grep_filter.debug = 1;
2073        } else if (!strcmp(arg, "--basic-regexp")) {
2074                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_BRE;
2075        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
2076                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_ERE;
2077        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
2078                revs->grep_filter.ignore_case = 1;
2079                DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
2080        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
2081                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
2082        } else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
2083                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
2084        } else if (!strcmp(arg, "--all-match")) {
2085                revs->grep_filter.all_match = 1;
2086        } else if (!strcmp(arg, "--invert-grep")) {
2087                revs->invert_grep = 1;
2088        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
2089                if (strcmp(optarg, "none"))
2090                        git_log_output_encoding = xstrdup(optarg);
2091                else
2092                        git_log_output_encoding = "";
2093                return argcount;
2094        } else if (!strcmp(arg, "--reverse")) {
2095                revs->reverse ^= 1;
2096        } else if (!strcmp(arg, "--children")) {
2097                revs->children.name = "children";
2098                revs->limited = 1;
2099        } else if (!strcmp(arg, "--ignore-missing")) {
2100                revs->ignore_missing = 1;
2101        } else if (!strcmp(arg, "--exclude-promisor-objects")) {
2102                if (fetch_if_missing)
2103                        die("BUG: exclude_promisor_objects can only be used when fetch_if_missing is 0");
2104                revs->exclude_promisor_objects = 1;
2105        } else {
2106                int opts = diff_opt_parse(&revs->diffopt, argv, argc, revs->prefix);
2107                if (!opts)
2108                        unkv[(*unkc)++] = arg;
2109                return opts;
2110        }
2111        if (revs->graph && revs->track_linear)
2112                die("--show-linear-break and --graph are incompatible");
2113
2114        return 1;
2115}
2116
2117void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2118                        const struct option *options,
2119                        const char * const usagestr[])
2120{
2121        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2122                                    &ctx->cpidx, ctx->out);
2123        if (n <= 0) {
2124                error("unknown option `%s'", ctx->argv[0]);
2125                usage_with_options(usagestr, options);
2126        }
2127        ctx->argv += n;
2128        ctx->argc -= n;
2129}
2130
2131static int for_each_bisect_ref(struct ref_store *refs, each_ref_fn fn,
2132                               void *cb_data, const char *term)
2133{
2134        struct strbuf bisect_refs = STRBUF_INIT;
2135        int status;
2136        strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
2137        status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data, 0);
2138        strbuf_release(&bisect_refs);
2139        return status;
2140}
2141
2142static int for_each_bad_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2143{
2144        return for_each_bisect_ref(refs, fn, cb_data, term_bad);
2145}
2146
2147static int for_each_good_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2148{
2149        return for_each_bisect_ref(refs, fn, cb_data, term_good);
2150}
2151
2152static int handle_revision_pseudo_opt(const char *submodule,
2153                                struct rev_info *revs,
2154                                int argc, const char **argv, int *flags)
2155{
2156        const char *arg = argv[0];
2157        const char *optarg;
2158        struct ref_store *refs;
2159        int argcount;
2160
2161        if (submodule) {
2162                /*
2163                 * We need some something like get_submodule_worktrees()
2164                 * before we can go through all worktrees of a submodule,
2165                 * .e.g with adding all HEADs from --all, which is not
2166                 * supported right now, so stick to single worktree.
2167                 */
2168                if (!revs->single_worktree)
2169                        die("BUG: --single-worktree cannot be used together with submodule");
2170                refs = get_submodule_ref_store(submodule);
2171        } else
2172                refs = get_main_ref_store();
2173
2174        /*
2175         * NOTE!
2176         *
2177         * Commands like "git shortlog" will not accept the options below
2178         * unless parse_revision_opt queues them (as opposed to erroring
2179         * out).
2180         *
2181         * When implementing your new pseudo-option, remember to
2182         * register it in the list at the top of handle_revision_opt.
2183         */
2184        if (!strcmp(arg, "--all")) {
2185                handle_refs(refs, revs, *flags, refs_for_each_ref);
2186                handle_refs(refs, revs, *flags, refs_head_ref);
2187                if (!revs->single_worktree) {
2188                        struct all_refs_cb cb;
2189
2190                        init_all_refs_cb(&cb, revs, *flags);
2191                        other_head_refs(handle_one_ref, &cb);
2192                }
2193                clear_ref_exclusion(&revs->ref_excludes);
2194        } else if (!strcmp(arg, "--branches")) {
2195                handle_refs(refs, revs, *flags, refs_for_each_branch_ref);
2196                clear_ref_exclusion(&revs->ref_excludes);
2197        } else if (!strcmp(arg, "--bisect")) {
2198                read_bisect_terms(&term_bad, &term_good);
2199                handle_refs(refs, revs, *flags, for_each_bad_bisect_ref);
2200                handle_refs(refs, revs, *flags ^ (UNINTERESTING | BOTTOM),
2201                            for_each_good_bisect_ref);
2202                revs->bisect = 1;
2203        } else if (!strcmp(arg, "--tags")) {
2204                handle_refs(refs, revs, *flags, refs_for_each_tag_ref);
2205                clear_ref_exclusion(&revs->ref_excludes);
2206        } else if (!strcmp(arg, "--remotes")) {
2207                handle_refs(refs, revs, *flags, refs_for_each_remote_ref);
2208                clear_ref_exclusion(&revs->ref_excludes);
2209        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2210                struct all_refs_cb cb;
2211                init_all_refs_cb(&cb, revs, *flags);
2212                for_each_glob_ref(handle_one_ref, optarg, &cb);
2213                clear_ref_exclusion(&revs->ref_excludes);
2214                return argcount;
2215        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2216                add_ref_exclusion(&revs->ref_excludes, optarg);
2217                return argcount;
2218        } else if (skip_prefix(arg, "--branches=", &optarg)) {
2219                struct all_refs_cb cb;
2220                init_all_refs_cb(&cb, revs, *flags);
2221                for_each_glob_ref_in(handle_one_ref, optarg, "refs/heads/", &cb);
2222                clear_ref_exclusion(&revs->ref_excludes);
2223        } else if (skip_prefix(arg, "--tags=", &optarg)) {
2224                struct all_refs_cb cb;
2225                init_all_refs_cb(&cb, revs, *flags);
2226                for_each_glob_ref_in(handle_one_ref, optarg, "refs/tags/", &cb);
2227                clear_ref_exclusion(&revs->ref_excludes);
2228        } else if (skip_prefix(arg, "--remotes=", &optarg)) {
2229                struct all_refs_cb cb;
2230                init_all_refs_cb(&cb, revs, *flags);
2231                for_each_glob_ref_in(handle_one_ref, optarg, "refs/remotes/", &cb);
2232                clear_ref_exclusion(&revs->ref_excludes);
2233        } else if (!strcmp(arg, "--reflog")) {
2234                add_reflogs_to_pending(revs, *flags);
2235        } else if (!strcmp(arg, "--indexed-objects")) {
2236                add_index_objects_to_pending(revs, *flags);
2237        } else if (!strcmp(arg, "--not")) {
2238                *flags ^= UNINTERESTING | BOTTOM;
2239        } else if (!strcmp(arg, "--no-walk")) {
2240                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2241        } else if (skip_prefix(arg, "--no-walk=", &optarg)) {
2242                /*
2243                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2244                 * not allowed, since the argument is optional.
2245                 */
2246                if (!strcmp(optarg, "sorted"))
2247                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2248                else if (!strcmp(optarg, "unsorted"))
2249                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2250                else
2251                        return error("invalid argument to --no-walk");
2252        } else if (!strcmp(arg, "--do-walk")) {
2253                revs->no_walk = 0;
2254        } else if (!strcmp(arg, "--single-worktree")) {
2255                revs->single_worktree = 1;
2256        } else {
2257                return 0;
2258        }
2259
2260        return 1;
2261}
2262
2263static void NORETURN diagnose_missing_default(const char *def)
2264{
2265        int flags;
2266        const char *refname;
2267
2268        refname = resolve_ref_unsafe(def, 0, NULL, &flags);
2269        if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
2270                die(_("your current branch appears to be broken"));
2271
2272        skip_prefix(refname, "refs/heads/", &refname);
2273        die(_("your current branch '%s' does not have any commits yet"),
2274            refname);
2275}
2276
2277/*
2278 * Parse revision information, filling in the "rev_info" structure,
2279 * and removing the used arguments from the argument list.
2280 *
2281 * Returns the number of arguments left that weren't recognized
2282 * (which are also moved to the head of the argument list)
2283 */
2284int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2285{
2286        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2287        struct argv_array prune_data = ARGV_ARRAY_INIT;
2288        const char *submodule = NULL;
2289
2290        if (opt)
2291                submodule = opt->submodule;
2292
2293        /* First, search for "--" */
2294        if (opt && opt->assume_dashdash) {
2295                seen_dashdash = 1;
2296        } else {
2297                seen_dashdash = 0;
2298                for (i = 1; i < argc; i++) {
2299                        const char *arg = argv[i];
2300                        if (strcmp(arg, "--"))
2301                                continue;
2302                        argv[i] = NULL;
2303                        argc = i;
2304                        if (argv[i + 1])
2305                                argv_array_pushv(&prune_data, argv + i + 1);
2306                        seen_dashdash = 1;
2307                        break;
2308                }
2309        }
2310
2311        /* Second, deal with arguments and options */
2312        flags = 0;
2313        revarg_opt = opt ? opt->revarg_opt : 0;
2314        if (seen_dashdash)
2315                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2316        read_from_stdin = 0;
2317        for (left = i = 1; i < argc; i++) {
2318                const char *arg = argv[i];
2319                if (*arg == '-') {
2320                        int opts;
2321
2322                        opts = handle_revision_pseudo_opt(submodule,
2323                                                revs, argc - i, argv + i,
2324                                                &flags);
2325                        if (opts > 0) {
2326                                i += opts - 1;
2327                                continue;
2328                        }
2329
2330                        if (!strcmp(arg, "--stdin")) {
2331                                if (revs->disable_stdin) {
2332                                        argv[left++] = arg;
2333                                        continue;
2334                                }
2335                                if (read_from_stdin++)
2336                                        die("--stdin given twice?");
2337                                read_revisions_from_stdin(revs, &prune_data);
2338                                continue;
2339                        }
2340
2341                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2342                        if (opts > 0) {
2343                                i += opts - 1;
2344                                continue;
2345                        }
2346                        if (opts < 0)
2347                                exit(128);
2348                        continue;
2349                }
2350
2351
2352                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2353                        int j;
2354                        if (seen_dashdash || *arg == '^')
2355                                die("bad revision '%s'", arg);
2356
2357                        /* If we didn't have a "--":
2358                         * (1) all filenames must exist;
2359                         * (2) all rev-args must not be interpretable
2360                         *     as a valid filename.
2361                         * but the latter we have checked in the main loop.
2362                         */
2363                        for (j = i; j < argc; j++)
2364                                verify_filename(revs->prefix, argv[j], j == i);
2365
2366                        argv_array_pushv(&prune_data, argv + i);
2367                        break;
2368                }
2369                else
2370                        got_rev_arg = 1;
2371        }
2372
2373        if (prune_data.argc) {
2374                /*
2375                 * If we need to introduce the magic "a lone ':' means no
2376                 * pathspec whatsoever", here is the place to do so.
2377                 *
2378                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2379                 *      prune_data.nr = 0;
2380                 *      prune_data.alloc = 0;
2381                 *      free(prune_data.path);
2382                 *      prune_data.path = NULL;
2383                 * } else {
2384                 *      terminate prune_data.alloc with NULL and
2385                 *      call init_pathspec() to set revs->prune_data here.
2386                 * }
2387                 */
2388                parse_pathspec(&revs->prune_data, 0, 0,
2389                               revs->prefix, prune_data.argv);
2390        }
2391        argv_array_clear(&prune_data);
2392
2393        if (revs->def == NULL)
2394                revs->def = opt ? opt->def : NULL;
2395        if (opt && opt->tweak)
2396                opt->tweak(revs, opt);
2397        if (revs->show_merge)
2398                prepare_show_merge(revs);
2399        if (revs->def && !revs->pending.nr && !revs->rev_input_given && !got_rev_arg) {
2400                struct object_id oid;
2401                struct object *object;
2402                struct object_context oc;
2403                if (get_oid_with_context(revs->def, 0, &oid, &oc))
2404                        diagnose_missing_default(revs->def);
2405                object = get_reference(revs, revs->def, &oid, 0);
2406                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2407        }
2408
2409        /* Did the user ask for any diff output? Run the diff! */
2410        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2411                revs->diff = 1;
2412
2413        /* Pickaxe, diff-filter and rename following need diffs */
2414        if (revs->diffopt.pickaxe ||
2415            revs->diffopt.filter ||
2416            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2417                revs->diff = 1;
2418
2419        if (revs->topo_order)
2420                revs->limited = 1;
2421
2422        if (revs->prune_data.nr) {
2423                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2424                /* Can't prune commits with rename following: the paths change.. */
2425                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2426                        revs->prune = 1;
2427                if (!revs->full_diff)
2428                        copy_pathspec(&revs->diffopt.pathspec,
2429                                      &revs->prune_data);
2430        }
2431        if (revs->combine_merges)
2432                revs->ignore_merges = 0;
2433        revs->diffopt.abbrev = revs->abbrev;
2434
2435        if (revs->line_level_traverse) {
2436                revs->limited = 1;
2437                revs->topo_order = 1;
2438        }
2439
2440        diff_setup_done(&revs->diffopt);
2441
2442        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2443                                 &revs->grep_filter);
2444        compile_grep_patterns(&revs->grep_filter);
2445
2446        if (revs->reverse && revs->reflog_info)
2447                die("cannot combine --reverse with --walk-reflogs");
2448        if (revs->reflog_info && revs->limited)
2449                die("cannot combine --walk-reflogs with history-limiting options");
2450        if (revs->rewrite_parents && revs->children.name)
2451                die("cannot combine --parents and --children");
2452
2453        /*
2454         * Limitations on the graph functionality
2455         */
2456        if (revs->reverse && revs->graph)
2457                die("cannot combine --reverse with --graph");
2458
2459        if (revs->reflog_info && revs->graph)
2460                die("cannot combine --walk-reflogs with --graph");
2461        if (revs->no_walk && revs->graph)
2462                die("cannot combine --no-walk with --graph");
2463        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2464                die("cannot use --grep-reflog without --walk-reflogs");
2465
2466        if (revs->first_parent_only && revs->bisect)
2467                die(_("--first-parent is incompatible with --bisect"));
2468
2469        if (revs->expand_tabs_in_log < 0)
2470                revs->expand_tabs_in_log = revs->expand_tabs_in_log_default;
2471
2472        return left;
2473}
2474
2475static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2476{
2477        struct commit_list *l = xcalloc(1, sizeof(*l));
2478
2479        l->item = child;
2480        l->next = add_decoration(&revs->children, &parent->object, l);
2481}
2482
2483static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2484{
2485        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2486        struct commit_list **pp, *p;
2487        int surviving_parents;
2488
2489        /* Examine existing parents while marking ones we have seen... */
2490        pp = &commit->parents;
2491        surviving_parents = 0;
2492        while ((p = *pp) != NULL) {
2493                struct commit *parent = p->item;
2494                if (parent->object.flags & TMP_MARK) {
2495                        *pp = p->next;
2496                        if (ts)
2497                                compact_treesame(revs, commit, surviving_parents);
2498                        continue;
2499                }
2500                parent->object.flags |= TMP_MARK;
2501                surviving_parents++;
2502                pp = &p->next;
2503        }
2504        /* clear the temporary mark */
2505        for (p = commit->parents; p; p = p->next) {
2506                p->item->object.flags &= ~TMP_MARK;
2507        }
2508        /* no update_treesame() - removing duplicates can't affect TREESAME */
2509        return surviving_parents;
2510}
2511
2512struct merge_simplify_state {
2513        struct commit *simplified;
2514};
2515
2516static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2517{
2518        struct merge_simplify_state *st;
2519
2520        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2521        if (!st) {
2522                st = xcalloc(1, sizeof(*st));
2523                add_decoration(&revs->merge_simplification, &commit->object, st);
2524        }
2525        return st;
2526}
2527
2528static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2529{
2530        struct commit_list *h = reduce_heads(commit->parents);
2531        int i = 0, marked = 0;
2532        struct commit_list *po, *pn;
2533
2534        /* Want these for sanity-checking only */
2535        int orig_cnt = commit_list_count(commit->parents);
2536        int cnt = commit_list_count(h);
2537
2538        /*
2539         * Not ready to remove items yet, just mark them for now, based
2540         * on the output of reduce_heads(). reduce_heads outputs the reduced
2541         * set in its original order, so this isn't too hard.
2542         */
2543        po = commit->parents;
2544        pn = h;
2545        while (po) {
2546                if (pn && po->item == pn->item) {
2547                        pn = pn->next;
2548                        i++;
2549                } else {
2550                        po->item->object.flags |= TMP_MARK;
2551                        marked++;
2552                }
2553                po=po->next;
2554        }
2555
2556        if (i != cnt || cnt+marked != orig_cnt)
2557                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2558
2559        free_commit_list(h);
2560
2561        return marked;
2562}
2563
2564static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2565{
2566        struct commit_list *p;
2567        int marked = 0;
2568
2569        for (p = commit->parents; p; p = p->next) {
2570                struct commit *parent = p->item;
2571                if (!parent->parents && (parent->object.flags & TREESAME)) {
2572                        parent->object.flags |= TMP_MARK;
2573                        marked++;
2574                }
2575        }
2576
2577        return marked;
2578}
2579
2580/*
2581 * Awkward naming - this means one parent we are TREESAME to.
2582 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2583 * empty tree). Better name suggestions?
2584 */
2585static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2586{
2587        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2588        struct commit *unmarked = NULL, *marked = NULL;
2589        struct commit_list *p;
2590        unsigned n;
2591
2592        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2593                if (ts->treesame[n]) {
2594                        if (p->item->object.flags & TMP_MARK) {
2595                                if (!marked)
2596                                        marked = p->item;
2597                        } else {
2598                                if (!unmarked) {
2599                                        unmarked = p->item;
2600                                        break;
2601                                }
2602                        }
2603                }
2604        }
2605
2606        /*
2607         * If we are TREESAME to a marked-for-deletion parent, but not to any
2608         * unmarked parents, unmark the first TREESAME parent. This is the
2609         * parent that the default simplify_history==1 scan would have followed,
2610         * and it doesn't make sense to omit that path when asking for a
2611         * simplified full history. Retaining it improves the chances of
2612         * understanding odd missed merges that took an old version of a file.
2613         *
2614         * Example:
2615         *
2616         *   I--------*X       A modified the file, but mainline merge X used
2617         *    \       /        "-s ours", so took the version from I. X is
2618         *     `-*A--'         TREESAME to I and !TREESAME to A.
2619         *
2620         * Default log from X would produce "I". Without this check,
2621         * --full-history --simplify-merges would produce "I-A-X", showing
2622         * the merge commit X and that it changed A, but not making clear that
2623         * it had just taken the I version. With this check, the topology above
2624         * is retained.
2625         *
2626         * Note that it is possible that the simplification chooses a different
2627         * TREESAME parent from the default, in which case this test doesn't
2628         * activate, and we _do_ drop the default parent. Example:
2629         *
2630         *   I------X         A modified the file, but it was reverted in B,
2631         *    \    /          meaning mainline merge X is TREESAME to both
2632         *    *A-*B           parents.
2633         *
2634         * Default log would produce "I" by following the first parent;
2635         * --full-history --simplify-merges will produce "I-A-B". But this is a
2636         * reasonable result - it presents a logical full history leading from
2637         * I to X, and X is not an important merge.
2638         */
2639        if (!unmarked && marked) {
2640                marked->object.flags &= ~TMP_MARK;
2641                return 1;
2642        }
2643
2644        return 0;
2645}
2646
2647static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2648{
2649        struct commit_list **pp, *p;
2650        int nth_parent, removed = 0;
2651
2652        pp = &commit->parents;
2653        nth_parent = 0;
2654        while ((p = *pp) != NULL) {
2655                struct commit *parent = p->item;
2656                if (parent->object.flags & TMP_MARK) {
2657                        parent->object.flags &= ~TMP_MARK;
2658                        *pp = p->next;
2659                        free(p);
2660                        removed++;
2661                        compact_treesame(revs, commit, nth_parent);
2662                        continue;
2663                }
2664                pp = &p->next;
2665                nth_parent++;
2666        }
2667
2668        /* Removing parents can only increase TREESAMEness */
2669        if (removed && !(commit->object.flags & TREESAME))
2670                update_treesame(revs, commit);
2671
2672        return nth_parent;
2673}
2674
2675static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2676{
2677        struct commit_list *p;
2678        struct commit *parent;
2679        struct merge_simplify_state *st, *pst;
2680        int cnt;
2681
2682        st = locate_simplify_state(revs, commit);
2683
2684        /*
2685         * Have we handled this one?
2686         */
2687        if (st->simplified)
2688                return tail;
2689
2690        /*
2691         * An UNINTERESTING commit simplifies to itself, so does a
2692         * root commit.  We do not rewrite parents of such commit
2693         * anyway.
2694         */
2695        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2696                st->simplified = commit;
2697                return tail;
2698        }
2699
2700        /*
2701         * Do we know what commit all of our parents that matter
2702         * should be rewritten to?  Otherwise we are not ready to
2703         * rewrite this one yet.
2704         */
2705        for (cnt = 0, p = commit->parents; p; p = p->next) {
2706                pst = locate_simplify_state(revs, p->item);
2707                if (!pst->simplified) {
2708                        tail = &commit_list_insert(p->item, tail)->next;
2709                        cnt++;
2710                }
2711                if (revs->first_parent_only)
2712                        break;
2713        }
2714        if (cnt) {
2715                tail = &commit_list_insert(commit, tail)->next;
2716                return tail;
2717        }
2718
2719        /*
2720         * Rewrite our list of parents. Note that this cannot
2721         * affect our TREESAME flags in any way - a commit is
2722         * always TREESAME to its simplification.
2723         */
2724        for (p = commit->parents; p; p = p->next) {
2725                pst = locate_simplify_state(revs, p->item);
2726                p->item = pst->simplified;
2727                if (revs->first_parent_only)
2728                        break;
2729        }
2730
2731        if (revs->first_parent_only)
2732                cnt = 1;
2733        else
2734                cnt = remove_duplicate_parents(revs, commit);
2735
2736        /*
2737         * It is possible that we are a merge and one side branch
2738         * does not have any commit that touches the given paths;
2739         * in such a case, the immediate parent from that branch
2740         * will be rewritten to be the merge base.
2741         *
2742         *      o----X          X: the commit we are looking at;
2743         *     /    /           o: a commit that touches the paths;
2744         * ---o----'
2745         *
2746         * Further, a merge of an independent branch that doesn't
2747         * touch the path will reduce to a treesame root parent:
2748         *
2749         *  ----o----X          X: the commit we are looking at;
2750         *          /           o: a commit that touches the paths;
2751         *         r            r: a root commit not touching the paths
2752         *
2753         * Detect and simplify both cases.
2754         */
2755        if (1 < cnt) {
2756                int marked = mark_redundant_parents(revs, commit);
2757                marked += mark_treesame_root_parents(revs, commit);
2758                if (marked)
2759                        marked -= leave_one_treesame_to_parent(revs, commit);
2760                if (marked)
2761                        cnt = remove_marked_parents(revs, commit);
2762        }
2763
2764        /*
2765         * A commit simplifies to itself if it is a root, if it is
2766         * UNINTERESTING, if it touches the given paths, or if it is a
2767         * merge and its parents don't simplify to one relevant commit
2768         * (the first two cases are already handled at the beginning of
2769         * this function).
2770         *
2771         * Otherwise, it simplifies to what its sole relevant parent
2772         * simplifies to.
2773         */
2774        if (!cnt ||
2775            (commit->object.flags & UNINTERESTING) ||
2776            !(commit->object.flags & TREESAME) ||
2777            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2778                st->simplified = commit;
2779        else {
2780                pst = locate_simplify_state(revs, parent);
2781                st->simplified = pst->simplified;
2782        }
2783        return tail;
2784}
2785
2786static void simplify_merges(struct rev_info *revs)
2787{
2788        struct commit_list *list, *next;
2789        struct commit_list *yet_to_do, **tail;
2790        struct commit *commit;
2791
2792        if (!revs->prune)
2793                return;
2794
2795        /* feed the list reversed */
2796        yet_to_do = NULL;
2797        for (list = revs->commits; list; list = next) {
2798                commit = list->item;
2799                next = list->next;
2800                /*
2801                 * Do not free(list) here yet; the original list
2802                 * is used later in this function.
2803                 */
2804                commit_list_insert(commit, &yet_to_do);
2805        }
2806        while (yet_to_do) {
2807                list = yet_to_do;
2808                yet_to_do = NULL;
2809                tail = &yet_to_do;
2810                while (list) {
2811                        commit = pop_commit(&list);
2812                        tail = simplify_one(revs, commit, tail);
2813                }
2814        }
2815
2816        /* clean up the result, removing the simplified ones */
2817        list = revs->commits;
2818        revs->commits = NULL;
2819        tail = &revs->commits;
2820        while (list) {
2821                struct merge_simplify_state *st;
2822
2823                commit = pop_commit(&list);
2824                st = locate_simplify_state(revs, commit);
2825                if (st->simplified == commit)
2826                        tail = &commit_list_insert(commit, tail)->next;
2827        }
2828}
2829
2830static void set_children(struct rev_info *revs)
2831{
2832        struct commit_list *l;
2833        for (l = revs->commits; l; l = l->next) {
2834                struct commit *commit = l->item;
2835                struct commit_list *p;
2836
2837                for (p = commit->parents; p; p = p->next)
2838                        add_child(revs, p->item, commit);
2839        }
2840}
2841
2842void reset_revision_walk(void)
2843{
2844        clear_object_flags(SEEN | ADDED | SHOWN);
2845}
2846
2847static int mark_uninteresting(const struct object_id *oid,
2848                              struct packed_git *pack,
2849                              uint32_t pos,
2850                              void *unused)
2851{
2852        struct object *o = parse_object(oid);
2853        o->flags |= UNINTERESTING | SEEN;
2854        return 0;
2855}
2856
2857int prepare_revision_walk(struct rev_info *revs)
2858{
2859        int i;
2860        struct object_array old_pending;
2861        struct commit_list **next = &revs->commits;
2862
2863        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2864        revs->pending.nr = 0;
2865        revs->pending.alloc = 0;
2866        revs->pending.objects = NULL;
2867        for (i = 0; i < old_pending.nr; i++) {
2868                struct object_array_entry *e = old_pending.objects + i;
2869                struct commit *commit = handle_commit(revs, e);
2870                if (commit) {
2871                        if (!(commit->object.flags & SEEN)) {
2872                                commit->object.flags |= SEEN;
2873                                next = commit_list_append(commit, next);
2874                        }
2875                }
2876        }
2877        if (!revs->leak_pending)
2878                object_array_clear(&old_pending);
2879
2880        /* Signal whether we need per-parent treesame decoration */
2881        if (revs->simplify_merges ||
2882            (revs->limited && limiting_can_increase_treesame(revs)))
2883                revs->treesame.name = "treesame";
2884
2885        if (revs->exclude_promisor_objects) {
2886                for_each_packed_object(mark_uninteresting, NULL,
2887                                       FOR_EACH_OBJECT_PROMISOR_ONLY);
2888        }
2889
2890        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2891                commit_list_sort_by_date(&revs->commits);
2892        if (revs->no_walk)
2893                return 0;
2894        if (revs->limited)
2895                if (limit_list(revs) < 0)
2896                        return -1;
2897        if (revs->topo_order)
2898                sort_in_topological_order(&revs->commits, revs->sort_order);
2899        if (revs->line_level_traverse)
2900                line_log_filter(revs);
2901        if (revs->simplify_merges)
2902                simplify_merges(revs);
2903        if (revs->children.name)
2904                set_children(revs);
2905        return 0;
2906}
2907
2908static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2909{
2910        struct commit_list *cache = NULL;
2911
2912        for (;;) {
2913                struct commit *p = *pp;
2914                if (!revs->limited)
2915                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2916                                return rewrite_one_error;
2917                if (p->object.flags & UNINTERESTING)
2918                        return rewrite_one_ok;
2919                if (!(p->object.flags & TREESAME))
2920                        return rewrite_one_ok;
2921                if (!p->parents)
2922                        return rewrite_one_noparents;
2923                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2924                        return rewrite_one_ok;
2925                *pp = p;
2926        }
2927}
2928
2929int rewrite_parents(struct rev_info *revs, struct commit *commit,
2930        rewrite_parent_fn_t rewrite_parent)
2931{
2932        struct commit_list **pp = &commit->parents;
2933        while (*pp) {
2934                struct commit_list *parent = *pp;
2935                switch (rewrite_parent(revs, &parent->item)) {
2936                case rewrite_one_ok:
2937                        break;
2938                case rewrite_one_noparents:
2939                        *pp = parent->next;
2940                        continue;
2941                case rewrite_one_error:
2942                        return -1;
2943                }
2944                pp = &parent->next;
2945        }
2946        remove_duplicate_parents(revs, commit);
2947        return 0;
2948}
2949
2950static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2951{
2952        char *person, *endp;
2953        size_t len, namelen, maillen;
2954        const char *name;
2955        const char *mail;
2956        struct ident_split ident;
2957
2958        person = strstr(buf->buf, what);
2959        if (!person)
2960                return 0;
2961
2962        person += strlen(what);
2963        endp = strchr(person, '\n');
2964        if (!endp)
2965                return 0;
2966
2967        len = endp - person;
2968
2969        if (split_ident_line(&ident, person, len))
2970                return 0;
2971
2972        mail = ident.mail_begin;
2973        maillen = ident.mail_end - ident.mail_begin;
2974        name = ident.name_begin;
2975        namelen = ident.name_end - ident.name_begin;
2976
2977        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2978                struct strbuf namemail = STRBUF_INIT;
2979
2980                strbuf_addf(&namemail, "%.*s <%.*s>",
2981                            (int)namelen, name, (int)maillen, mail);
2982
2983                strbuf_splice(buf, ident.name_begin - buf->buf,
2984                              ident.mail_end - ident.name_begin + 1,
2985                              namemail.buf, namemail.len);
2986
2987                strbuf_release(&namemail);
2988
2989                return 1;
2990        }
2991
2992        return 0;
2993}
2994
2995static int commit_match(struct commit *commit, struct rev_info *opt)
2996{
2997        int retval;
2998        const char *encoding;
2999        const char *message;
3000        struct strbuf buf = STRBUF_INIT;
3001
3002        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
3003                return 1;
3004
3005        /* Prepend "fake" headers as needed */
3006        if (opt->grep_filter.use_reflog_filter) {
3007                strbuf_addstr(&buf, "reflog ");
3008                get_reflog_message(&buf, opt->reflog_info);
3009                strbuf_addch(&buf, '\n');
3010        }
3011
3012        /*
3013         * We grep in the user's output encoding, under the assumption that it
3014         * is the encoding they are most likely to write their grep pattern
3015         * for. In addition, it means we will match the "notes" encoding below,
3016         * so we will not end up with a buffer that has two different encodings
3017         * in it.
3018         */
3019        encoding = get_log_output_encoding();
3020        message = logmsg_reencode(commit, NULL, encoding);
3021
3022        /* Copy the commit to temporary if we are using "fake" headers */
3023        if (buf.len)
3024                strbuf_addstr(&buf, message);
3025
3026        if (opt->grep_filter.header_list && opt->mailmap) {
3027                if (!buf.len)
3028                        strbuf_addstr(&buf, message);
3029
3030                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
3031                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
3032        }
3033
3034        /* Append "fake" message parts as needed */
3035        if (opt->show_notes) {
3036                if (!buf.len)
3037                        strbuf_addstr(&buf, message);
3038                format_display_notes(&commit->object.oid, &buf, encoding, 1);
3039        }
3040
3041        /*
3042         * Find either in the original commit message, or in the temporary.
3043         * Note that we cast away the constness of "message" here. It is
3044         * const because it may come from the cached commit buffer. That's OK,
3045         * because we know that it is modifiable heap memory, and that while
3046         * grep_buffer may modify it for speed, it will restore any
3047         * changes before returning.
3048         */
3049        if (buf.len)
3050                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
3051        else
3052                retval = grep_buffer(&opt->grep_filter,
3053                                     (char *)message, strlen(message));
3054        strbuf_release(&buf);
3055        unuse_commit_buffer(commit, message);
3056        return opt->invert_grep ? !retval : retval;
3057}
3058
3059static inline int want_ancestry(const struct rev_info *revs)
3060{
3061        return (revs->rewrite_parents || revs->children.name);
3062}
3063
3064/*
3065 * Return a timestamp to be used for --since/--until comparisons for this
3066 * commit, based on the revision options.
3067 */
3068static timestamp_t comparison_date(const struct rev_info *revs,
3069                                   struct commit *commit)
3070{
3071        return revs->reflog_info ?
3072                get_reflog_timestamp(revs->reflog_info) :
3073                commit->date;
3074}
3075
3076enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
3077{
3078        if (commit->object.flags & SHOWN)
3079                return commit_ignore;
3080        if (revs->unpacked && has_sha1_pack(commit->object.oid.hash))
3081                return commit_ignore;
3082        if (revs->show_all)
3083                return commit_show;
3084        if (commit->object.flags & UNINTERESTING)
3085                return commit_ignore;
3086        if (revs->min_age != -1 &&
3087            comparison_date(revs, commit) > revs->min_age)
3088                        return commit_ignore;
3089        if (revs->min_parents || (revs->max_parents >= 0)) {
3090                int n = commit_list_count(commit->parents);
3091                if ((n < revs->min_parents) ||
3092                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
3093                        return commit_ignore;
3094        }
3095        if (!commit_match(commit, revs))
3096                return commit_ignore;
3097        if (revs->prune && revs->dense) {
3098                /* Commit without changes? */
3099                if (commit->object.flags & TREESAME) {
3100                        int n;
3101                        struct commit_list *p;
3102                        /* drop merges unless we want parenthood */
3103                        if (!want_ancestry(revs))
3104                                return commit_ignore;
3105                        /*
3106                         * If we want ancestry, then need to keep any merges
3107                         * between relevant commits to tie together topology.
3108                         * For consistency with TREESAME and simplification
3109                         * use "relevant" here rather than just INTERESTING,
3110                         * to treat bottom commit(s) as part of the topology.
3111                         */
3112                        for (n = 0, p = commit->parents; p; p = p->next)
3113                                if (relevant_commit(p->item))
3114                                        if (++n >= 2)
3115                                                return commit_show;
3116                        return commit_ignore;
3117                }
3118        }
3119        return commit_show;
3120}
3121
3122define_commit_slab(saved_parents, struct commit_list *);
3123
3124#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
3125
3126/*
3127 * You may only call save_parents() once per commit (this is checked
3128 * for non-root commits).
3129 */
3130static void save_parents(struct rev_info *revs, struct commit *commit)
3131{
3132        struct commit_list **pp;
3133
3134        if (!revs->saved_parents_slab) {
3135                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
3136                init_saved_parents(revs->saved_parents_slab);
3137        }
3138
3139        pp = saved_parents_at(revs->saved_parents_slab, commit);
3140
3141        /*
3142         * When walking with reflogs, we may visit the same commit
3143         * several times: once for each appearance in the reflog.
3144         *
3145         * In this case, save_parents() will be called multiple times.
3146         * We want to keep only the first set of parents.  We need to
3147         * store a sentinel value for an empty (i.e., NULL) parent
3148         * list to distinguish it from a not-yet-saved list, however.
3149         */
3150        if (*pp)
3151                return;
3152        if (commit->parents)
3153                *pp = copy_commit_list(commit->parents);
3154        else
3155                *pp = EMPTY_PARENT_LIST;
3156}
3157
3158static void free_saved_parents(struct rev_info *revs)
3159{
3160        if (revs->saved_parents_slab)
3161                clear_saved_parents(revs->saved_parents_slab);
3162}
3163
3164struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
3165{
3166        struct commit_list *parents;
3167
3168        if (!revs->saved_parents_slab)
3169                return commit->parents;
3170
3171        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3172        if (parents == EMPTY_PARENT_LIST)
3173                return NULL;
3174        return parents;
3175}
3176
3177enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
3178{
3179        enum commit_action action = get_commit_action(revs, commit);
3180
3181        if (action == commit_show &&
3182            !revs->show_all &&
3183            revs->prune && revs->dense && want_ancestry(revs)) {
3184                /*
3185                 * --full-diff on simplified parents is no good: it
3186                 * will show spurious changes from the commits that
3187                 * were elided.  So we save the parents on the side
3188                 * when --full-diff is in effect.
3189                 */
3190                if (revs->full_diff)
3191                        save_parents(revs, commit);
3192                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3193                        return commit_error;
3194        }
3195        return action;
3196}
3197
3198static void track_linear(struct rev_info *revs, struct commit *commit)
3199{
3200        if (revs->track_first_time) {
3201                revs->linear = 1;
3202                revs->track_first_time = 0;
3203        } else {
3204                struct commit_list *p;
3205                for (p = revs->previous_parents; p; p = p->next)
3206                        if (p->item == NULL || /* first commit */
3207                            !oidcmp(&p->item->object.oid, &commit->object.oid))
3208                                break;
3209                revs->linear = p != NULL;
3210        }
3211        if (revs->reverse) {
3212                if (revs->linear)
3213                        commit->object.flags |= TRACK_LINEAR;
3214        }
3215        free_commit_list(revs->previous_parents);
3216        revs->previous_parents = copy_commit_list(commit->parents);
3217}
3218
3219static struct commit *get_revision_1(struct rev_info *revs)
3220{
3221        while (1) {
3222                struct commit *commit;
3223
3224                if (revs->reflog_info)
3225                        commit = next_reflog_entry(revs->reflog_info);
3226                else
3227                        commit = pop_commit(&revs->commits);
3228
3229                if (!commit)
3230                        return NULL;
3231
3232                if (revs->reflog_info)
3233                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3234
3235                /*
3236                 * If we haven't done the list limiting, we need to look at
3237                 * the parents here. We also need to do the date-based limiting
3238                 * that we'd otherwise have done in limit_list().
3239                 */
3240                if (!revs->limited) {
3241                        if (revs->max_age != -1 &&
3242                            comparison_date(revs, commit) < revs->max_age)
3243                                continue;
3244
3245                        if (revs->reflog_info)
3246                                try_to_simplify_commit(revs, commit);
3247                        else if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3248                                if (!revs->ignore_missing_links)
3249                                        die("Failed to traverse parents of commit %s",
3250                                                oid_to_hex(&commit->object.oid));
3251                        }
3252                }
3253
3254                switch (simplify_commit(revs, commit)) {
3255                case commit_ignore:
3256                        continue;
3257                case commit_error:
3258                        die("Failed to simplify parents of commit %s",
3259                            oid_to_hex(&commit->object.oid));
3260                default:
3261                        if (revs->track_linear)
3262                                track_linear(revs, commit);
3263                        return commit;
3264                }
3265        }
3266}
3267
3268/*
3269 * Return true for entries that have not yet been shown.  (This is an
3270 * object_array_each_func_t.)
3271 */
3272static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3273{
3274        return !(entry->item->flags & SHOWN);
3275}
3276
3277/*
3278 * If array is on the verge of a realloc, garbage-collect any entries
3279 * that have already been shown to try to free up some space.
3280 */
3281static void gc_boundary(struct object_array *array)
3282{
3283        if (array->nr == array->alloc)
3284                object_array_filter(array, entry_unshown, NULL);
3285}
3286
3287static void create_boundary_commit_list(struct rev_info *revs)
3288{
3289        unsigned i;
3290        struct commit *c;
3291        struct object_array *array = &revs->boundary_commits;
3292        struct object_array_entry *objects = array->objects;
3293
3294        /*
3295         * If revs->commits is non-NULL at this point, an error occurred in
3296         * get_revision_1().  Ignore the error and continue printing the
3297         * boundary commits anyway.  (This is what the code has always
3298         * done.)
3299         */
3300        if (revs->commits) {
3301                free_commit_list(revs->commits);
3302                revs->commits = NULL;
3303        }
3304
3305        /*
3306         * Put all of the actual boundary commits from revs->boundary_commits
3307         * into revs->commits
3308         */
3309        for (i = 0; i < array->nr; i++) {
3310                c = (struct commit *)(objects[i].item);
3311                if (!c)
3312                        continue;
3313                if (!(c->object.flags & CHILD_SHOWN))
3314                        continue;
3315                if (c->object.flags & (SHOWN | BOUNDARY))
3316                        continue;
3317                c->object.flags |= BOUNDARY;
3318                commit_list_insert(c, &revs->commits);
3319        }
3320
3321        /*
3322         * If revs->topo_order is set, sort the boundary commits
3323         * in topological order
3324         */
3325        sort_in_topological_order(&revs->commits, revs->sort_order);
3326}
3327
3328static struct commit *get_revision_internal(struct rev_info *revs)
3329{
3330        struct commit *c = NULL;
3331        struct commit_list *l;
3332
3333        if (revs->boundary == 2) {
3334                /*
3335                 * All of the normal commits have already been returned,
3336                 * and we are now returning boundary commits.
3337                 * create_boundary_commit_list() has populated
3338                 * revs->commits with the remaining commits to return.
3339                 */
3340                c = pop_commit(&revs->commits);
3341                if (c)
3342                        c->object.flags |= SHOWN;
3343                return c;
3344        }
3345
3346        /*
3347         * If our max_count counter has reached zero, then we are done. We
3348         * don't simply return NULL because we still might need to show
3349         * boundary commits. But we want to avoid calling get_revision_1, which
3350         * might do a considerable amount of work finding the next commit only
3351         * for us to throw it away.
3352         *
3353         * If it is non-zero, then either we don't have a max_count at all
3354         * (-1), or it is still counting, in which case we decrement.
3355         */
3356        if (revs->max_count) {
3357                c = get_revision_1(revs);
3358                if (c) {
3359                        while (revs->skip_count > 0) {
3360                                revs->skip_count--;
3361                                c = get_revision_1(revs);
3362                                if (!c)
3363                                        break;
3364                        }
3365                }
3366
3367                if (revs->max_count > 0)
3368                        revs->max_count--;
3369        }
3370
3371        if (c)
3372                c->object.flags |= SHOWN;
3373
3374        if (!revs->boundary)
3375                return c;
3376
3377        if (!c) {
3378                /*
3379                 * get_revision_1() runs out the commits, and
3380                 * we are done computing the boundaries.
3381                 * switch to boundary commits output mode.
3382                 */
3383                revs->boundary = 2;
3384
3385                /*
3386                 * Update revs->commits to contain the list of
3387                 * boundary commits.
3388                 */
3389                create_boundary_commit_list(revs);
3390
3391                return get_revision_internal(revs);
3392        }
3393
3394        /*
3395         * boundary commits are the commits that are parents of the
3396         * ones we got from get_revision_1() but they themselves are
3397         * not returned from get_revision_1().  Before returning
3398         * 'c', we need to mark its parents that they could be boundaries.
3399         */
3400
3401        for (l = c->parents; l; l = l->next) {
3402                struct object *p;
3403                p = &(l->item->object);
3404                if (p->flags & (CHILD_SHOWN | SHOWN))
3405                        continue;
3406                p->flags |= CHILD_SHOWN;
3407                gc_boundary(&revs->boundary_commits);
3408                add_object_array(p, NULL, &revs->boundary_commits);
3409        }
3410
3411        return c;
3412}
3413
3414struct commit *get_revision(struct rev_info *revs)
3415{
3416        struct commit *c;
3417        struct commit_list *reversed;
3418
3419        if (revs->reverse) {
3420                reversed = NULL;
3421                while ((c = get_revision_internal(revs)))
3422                        commit_list_insert(c, &reversed);
3423                revs->commits = reversed;
3424                revs->reverse = 0;
3425                revs->reverse_output_stage = 1;
3426        }
3427
3428        if (revs->reverse_output_stage) {
3429                c = pop_commit(&revs->commits);
3430                if (revs->track_linear)
3431                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3432                return c;
3433        }
3434
3435        c = get_revision_internal(revs);
3436        if (c && revs->graph)
3437                graph_update(revs->graph, c);
3438        if (!c) {
3439                free_saved_parents(revs);
3440                if (revs->previous_parents) {
3441                        free_commit_list(revs->previous_parents);
3442                        revs->previous_parents = NULL;
3443                }
3444        }
3445        return c;
3446}
3447
3448char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3449{
3450        if (commit->object.flags & BOUNDARY)
3451                return "-";
3452        else if (commit->object.flags & UNINTERESTING)
3453                return "^";
3454        else if (commit->object.flags & PATCHSAME)
3455                return "=";
3456        else if (!revs || revs->left_right) {
3457                if (commit->object.flags & SYMMETRIC_LEFT)
3458                        return "<";
3459                else
3460                        return ">";
3461        } else if (revs->graph)
3462                return "*";
3463        else if (revs->cherry_mark)
3464                return "+";
3465        return "";
3466}
3467
3468void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3469{
3470        char *mark = get_revision_mark(revs, commit);
3471        if (!strlen(mark))
3472                return;
3473        fputs(mark, stdout);
3474        putchar(' ');
3475}