revision.con commit Merge branch 'ks/help-alias-label' (5079cc8)
   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
  25volatile show_early_output_fn_t show_early_output;
  26
  27static const char *term_bad;
  28static const char *term_good;
  29
  30void show_object_with_name(FILE *out, struct object *obj, const char *name)
  31{
  32        const char *p;
  33
  34        fprintf(out, "%s ", oid_to_hex(&obj->oid));
  35        for (p = name; *p && *p != '\n'; p++)
  36                fputc(*p, out);
  37        fputc('\n', out);
  38}
  39
  40static void mark_blob_uninteresting(struct blob *blob)
  41{
  42        if (!blob)
  43                return;
  44        if (blob->object.flags & UNINTERESTING)
  45                return;
  46        blob->object.flags |= UNINTERESTING;
  47}
  48
  49static void mark_tree_contents_uninteresting(struct tree *tree)
  50{
  51        struct tree_desc desc;
  52        struct name_entry entry;
  53        struct object *obj = &tree->object;
  54
  55        if (!has_object_file(&obj->oid))
  56                return;
  57        if (parse_tree(tree) < 0)
  58                die("bad tree %s", oid_to_hex(&obj->oid));
  59
  60        init_tree_desc(&desc, tree->buffer, tree->size);
  61        while (tree_entry(&desc, &entry)) {
  62                switch (object_type(entry.mode)) {
  63                case OBJ_TREE:
  64                        mark_tree_uninteresting(lookup_tree(entry.oid));
  65                        break;
  66                case OBJ_BLOB:
  67                        mark_blob_uninteresting(lookup_blob(entry.oid));
  68                        break;
  69                default:
  70                        /* Subproject commit - not in this repository */
  71                        break;
  72                }
  73        }
  74
  75        /*
  76         * We don't care about the tree any more
  77         * after it has been marked uninteresting.
  78         */
  79        free_tree_buffer(tree);
  80}
  81
  82void mark_tree_uninteresting(struct tree *tree)
  83{
  84        struct object *obj;
  85
  86        if (!tree)
  87                return;
  88
  89        obj = &tree->object;
  90        if (obj->flags & UNINTERESTING)
  91                return;
  92        obj->flags |= UNINTERESTING;
  93        mark_tree_contents_uninteresting(tree);
  94}
  95
  96void mark_parents_uninteresting(struct commit *commit)
  97{
  98        struct commit_list *parents = NULL, *l;
  99
 100        for (l = commit->parents; l; l = l->next)
 101                commit_list_insert(l->item, &parents);
 102
 103        while (parents) {
 104                struct commit *commit = pop_commit(&parents);
 105
 106                while (commit) {
 107                        /*
 108                         * A missing commit is ok iff its parent is marked
 109                         * uninteresting.
 110                         *
 111                         * We just mark such a thing parsed, so that when
 112                         * it is popped next time around, we won't be trying
 113                         * to parse it and get an error.
 114                         */
 115                        if (!has_object_file(&commit->object.oid))
 116                                commit->object.parsed = 1;
 117
 118                        if (commit->object.flags & UNINTERESTING)
 119                                break;
 120
 121                        commit->object.flags |= UNINTERESTING;
 122
 123                        /*
 124                         * Normally we haven't parsed the parent
 125                         * yet, so we won't have a parent of a parent
 126                         * here. However, it may turn out that we've
 127                         * reached this commit some other way (where it
 128                         * wasn't uninteresting), in which case we need
 129                         * to mark its parents recursively too..
 130                         */
 131                        if (!commit->parents)
 132                                break;
 133
 134                        for (l = commit->parents->next; l; l = l->next)
 135                                commit_list_insert(l->item, &parents);
 136                        commit = commit->parents->item;
 137                }
 138        }
 139}
 140
 141static void add_pending_object_with_path(struct rev_info *revs,
 142                                         struct object *obj,
 143                                         const char *name, unsigned mode,
 144                                         const char *path)
 145{
 146        if (!obj)
 147                return;
 148        if (revs->no_walk && (obj->flags & UNINTERESTING))
 149                revs->no_walk = 0;
 150        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 151                struct strbuf buf = STRBUF_INIT;
 152                int len = interpret_branch_name(name, 0, &buf, 0);
 153
 154                if (0 < len && name[len] && buf.len)
 155                        strbuf_addstr(&buf, name + len);
 156                add_reflog_for_walk(revs->reflog_info,
 157                                    (struct commit *)obj,
 158                                    buf.buf[0] ? buf.buf: name);
 159                strbuf_release(&buf);
 160                return; /* do not add the commit itself */
 161        }
 162        add_object_array_with_path(obj, name, &revs->pending, mode, path);
 163}
 164
 165static void add_pending_object_with_mode(struct rev_info *revs,
 166                                         struct object *obj,
 167                                         const char *name, unsigned mode)
 168{
 169        add_pending_object_with_path(revs, obj, name, mode, NULL);
 170}
 171
 172void add_pending_object(struct rev_info *revs,
 173                        struct object *obj, const char *name)
 174{
 175        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 176}
 177
 178void add_head_to_pending(struct rev_info *revs)
 179{
 180        struct object_id oid;
 181        struct object *obj;
 182        if (get_oid("HEAD", &oid))
 183                return;
 184        obj = parse_object(&oid);
 185        if (!obj)
 186                return;
 187        add_pending_object(revs, obj, "HEAD");
 188}
 189
 190static struct object *get_reference(struct rev_info *revs, const char *name,
 191                                    const struct object_id *oid,
 192                                    unsigned int flags)
 193{
 194        struct object *object;
 195
 196        object = parse_object(oid);
 197        if (!object) {
 198                if (revs->ignore_missing)
 199                        return object;
 200                die("bad object %s", name);
 201        }
 202        object->flags |= flags;
 203        return object;
 204}
 205
 206void add_pending_oid(struct rev_info *revs, const char *name,
 207                      const struct object_id *oid, unsigned int flags)
 208{
 209        struct object *object = get_reference(revs, name, oid, flags);
 210        add_pending_object(revs, object, name);
 211}
 212
 213static struct commit *handle_commit(struct rev_info *revs,
 214                                    struct object_array_entry *entry)
 215{
 216        struct object *object = entry->item;
 217        const char *name = entry->name;
 218        const char *path = entry->path;
 219        unsigned int mode = entry->mode;
 220        unsigned long flags = object->flags;
 221
 222        /*
 223         * Tag object? Look what it points to..
 224         */
 225        while (object->type == OBJ_TAG) {
 226                struct tag *tag = (struct tag *) object;
 227                if (revs->tag_objects && !(flags & UNINTERESTING))
 228                        add_pending_object(revs, object, tag->tag);
 229                if (!tag->tagged)
 230                        die("bad tag");
 231                object = parse_object(&tag->tagged->oid);
 232                if (!object) {
 233                        if (revs->ignore_missing_links || (flags & UNINTERESTING))
 234                                return NULL;
 235                        die("bad object %s", oid_to_hex(&tag->tagged->oid));
 236                }
 237                object->flags |= flags;
 238                /*
 239                 * We'll handle the tagged object by looping or dropping
 240                 * through to the non-tag handlers below. Do not
 241                 * propagate path data from the tag's pending entry.
 242                 */
 243                path = NULL;
 244                mode = 0;
 245        }
 246
 247        /*
 248         * Commit object? Just return it, we'll do all the complex
 249         * reachability crud.
 250         */
 251        if (object->type == OBJ_COMMIT) {
 252                struct commit *commit = (struct commit *)object;
 253                if (parse_commit(commit) < 0)
 254                        die("unable to parse commit %s", name);
 255                if (flags & UNINTERESTING) {
 256                        mark_parents_uninteresting(commit);
 257                        revs->limited = 1;
 258                }
 259                if (revs->show_source && !commit->util)
 260                        commit->util = xstrdup(name);
 261                return commit;
 262        }
 263
 264        /*
 265         * Tree object? Either mark it uninteresting, or add it
 266         * to the list of objects to look at later..
 267         */
 268        if (object->type == OBJ_TREE) {
 269                struct tree *tree = (struct tree *)object;
 270                if (!revs->tree_objects)
 271                        return NULL;
 272                if (flags & UNINTERESTING) {
 273                        mark_tree_contents_uninteresting(tree);
 274                        return NULL;
 275                }
 276                add_pending_object_with_path(revs, object, name, mode, path);
 277                return NULL;
 278        }
 279
 280        /*
 281         * Blob object? You know the drill by now..
 282         */
 283        if (object->type == OBJ_BLOB) {
 284                if (!revs->blob_objects)
 285                        return NULL;
 286                if (flags & UNINTERESTING)
 287                        return NULL;
 288                add_pending_object_with_path(revs, object, name, mode, path);
 289                return NULL;
 290        }
 291        die("%s is unknown object", name);
 292}
 293
 294static int everybody_uninteresting(struct commit_list *orig,
 295                                   struct commit **interesting_cache)
 296{
 297        struct commit_list *list = orig;
 298
 299        if (*interesting_cache) {
 300                struct commit *commit = *interesting_cache;
 301                if (!(commit->object.flags & UNINTERESTING))
 302                        return 0;
 303        }
 304
 305        while (list) {
 306                struct commit *commit = list->item;
 307                list = list->next;
 308                if (commit->object.flags & UNINTERESTING)
 309                        continue;
 310
 311                *interesting_cache = commit;
 312                return 0;
 313        }
 314        return 1;
 315}
 316
 317/*
 318 * A definition of "relevant" commit that we can use to simplify limited graphs
 319 * by eliminating side branches.
 320 *
 321 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 322 * in our list), or that is a specified BOTTOM commit. Then after computing
 323 * a limited list, during processing we can generally ignore boundary merges
 324 * coming from outside the graph, (ie from irrelevant parents), and treat
 325 * those merges as if they were single-parent. TREESAME is defined to consider
 326 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 327 * we don't care if we were !TREESAME to non-graph parents.
 328 *
 329 * Treating bottom commits as relevant ensures that a limited graph's
 330 * connection to the actual bottom commit is not viewed as a side branch, but
 331 * treated as part of the graph. For example:
 332 *
 333 *   ....Z...A---X---o---o---B
 334 *        .     /
 335 *         W---Y
 336 *
 337 * When computing "A..B", the A-X connection is at least as important as
 338 * Y-X, despite A being flagged UNINTERESTING.
 339 *
 340 * And when computing --ancestry-path "A..B", the A-X connection is more
 341 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 342 */
 343static inline int relevant_commit(struct commit *commit)
 344{
 345        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 346}
 347
 348/*
 349 * Return a single relevant commit from a parent list. If we are a TREESAME
 350 * commit, and this selects one of our parents, then we can safely simplify to
 351 * that parent.
 352 */
 353static struct commit *one_relevant_parent(const struct rev_info *revs,
 354                                          struct commit_list *orig)
 355{
 356        struct commit_list *list = orig;
 357        struct commit *relevant = NULL;
 358
 359        if (!orig)
 360                return NULL;
 361
 362        /*
 363         * For 1-parent commits, or if first-parent-only, then return that
 364         * first parent (even if not "relevant" by the above definition).
 365         * TREESAME will have been set purely on that parent.
 366         */
 367        if (revs->first_parent_only || !orig->next)
 368                return orig->item;
 369
 370        /*
 371         * For multi-parent commits, identify a sole relevant parent, if any.
 372         * If we have only one relevant parent, then TREESAME will be set purely
 373         * with regard to that parent, and we can simplify accordingly.
 374         *
 375         * If we have more than one relevant parent, or no relevant parents
 376         * (and multiple irrelevant ones), then we can't select a parent here
 377         * and return NULL.
 378         */
 379        while (list) {
 380                struct commit *commit = list->item;
 381                list = list->next;
 382                if (relevant_commit(commit)) {
 383                        if (relevant)
 384                                return NULL;
 385                        relevant = commit;
 386                }
 387        }
 388        return relevant;
 389}
 390
 391/*
 392 * The goal is to get REV_TREE_NEW as the result only if the
 393 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 394 * if the whole diff is removal of old data, and otherwise
 395 * REV_TREE_DIFFERENT (of course if the trees are the same we
 396 * want REV_TREE_SAME).
 397 * That means that once we get to REV_TREE_DIFFERENT, we do not
 398 * have to look any further.
 399 */
 400static int tree_difference = REV_TREE_SAME;
 401
 402static void file_add_remove(struct diff_options *options,
 403                    int addremove, unsigned mode,
 404                    const struct object_id *oid,
 405                    int oid_valid,
 406                    const char *fullpath, unsigned dirty_submodule)
 407{
 408        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 409
 410        tree_difference |= diff;
 411        if (tree_difference == REV_TREE_DIFFERENT)
 412                DIFF_OPT_SET(options, HAS_CHANGES);
 413}
 414
 415static void file_change(struct diff_options *options,
 416                 unsigned old_mode, unsigned new_mode,
 417                 const struct object_id *old_oid,
 418                 const struct object_id *new_oid,
 419                 int old_oid_valid, int new_oid_valid,
 420                 const char *fullpath,
 421                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 422{
 423        tree_difference = REV_TREE_DIFFERENT;
 424        DIFF_OPT_SET(options, HAS_CHANGES);
 425}
 426
 427static int rev_compare_tree(struct rev_info *revs,
 428                            struct commit *parent, struct commit *commit)
 429{
 430        struct tree *t1 = parent->tree;
 431        struct tree *t2 = commit->tree;
 432
 433        if (!t1)
 434                return REV_TREE_NEW;
 435        if (!t2)
 436                return REV_TREE_OLD;
 437
 438        if (revs->simplify_by_decoration) {
 439                /*
 440                 * If we are simplifying by decoration, then the commit
 441                 * is worth showing if it has a tag pointing at it.
 442                 */
 443                if (get_name_decoration(&commit->object))
 444                        return REV_TREE_DIFFERENT;
 445                /*
 446                 * A commit that is not pointed by a tag is uninteresting
 447                 * if we are not limited by path.  This means that you will
 448                 * see the usual "commits that touch the paths" plus any
 449                 * tagged commit by specifying both --simplify-by-decoration
 450                 * and pathspec.
 451                 */
 452                if (!revs->prune_data.nr)
 453                        return REV_TREE_SAME;
 454        }
 455
 456        tree_difference = REV_TREE_SAME;
 457        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 458        if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
 459                           &revs->pruning) < 0)
 460                return REV_TREE_DIFFERENT;
 461        return tree_difference;
 462}
 463
 464static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 465{
 466        int retval;
 467        struct tree *t1 = commit->tree;
 468
 469        if (!t1)
 470                return 0;
 471
 472        tree_difference = REV_TREE_SAME;
 473        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 474        retval = diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);
 475
 476        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 477}
 478
 479struct treesame_state {
 480        unsigned int nparents;
 481        unsigned char treesame[FLEX_ARRAY];
 482};
 483
 484static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 485{
 486        unsigned n = commit_list_count(commit->parents);
 487        struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 488        st->nparents = n;
 489        add_decoration(&revs->treesame, &commit->object, st);
 490        return st;
 491}
 492
 493/*
 494 * Must be called immediately after removing the nth_parent from a commit's
 495 * parent list, if we are maintaining the per-parent treesame[] decoration.
 496 * This does not recalculate the master TREESAME flag - update_treesame()
 497 * should be called to update it after a sequence of treesame[] modifications
 498 * that may have affected it.
 499 */
 500static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 501{
 502        struct treesame_state *st;
 503        int old_same;
 504
 505        if (!commit->parents) {
 506                /*
 507                 * Have just removed the only parent from a non-merge.
 508                 * Different handling, as we lack decoration.
 509                 */
 510                if (nth_parent != 0)
 511                        die("compact_treesame %u", nth_parent);
 512                old_same = !!(commit->object.flags & TREESAME);
 513                if (rev_same_tree_as_empty(revs, commit))
 514                        commit->object.flags |= TREESAME;
 515                else
 516                        commit->object.flags &= ~TREESAME;
 517                return old_same;
 518        }
 519
 520        st = lookup_decoration(&revs->treesame, &commit->object);
 521        if (!st || nth_parent >= st->nparents)
 522                die("compact_treesame %u", nth_parent);
 523
 524        old_same = st->treesame[nth_parent];
 525        memmove(st->treesame + nth_parent,
 526                st->treesame + nth_parent + 1,
 527                st->nparents - nth_parent - 1);
 528
 529        /*
 530         * If we've just become a non-merge commit, update TREESAME
 531         * immediately, and remove the no-longer-needed decoration.
 532         * If still a merge, defer update until update_treesame().
 533         */
 534        if (--st->nparents == 1) {
 535                if (commit->parents->next)
 536                        die("compact_treesame parents mismatch");
 537                if (st->treesame[0] && revs->dense)
 538                        commit->object.flags |= TREESAME;
 539                else
 540                        commit->object.flags &= ~TREESAME;
 541                free(add_decoration(&revs->treesame, &commit->object, NULL));
 542        }
 543
 544        return old_same;
 545}
 546
 547static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 548{
 549        if (commit->parents && commit->parents->next) {
 550                unsigned n;
 551                struct treesame_state *st;
 552                struct commit_list *p;
 553                unsigned relevant_parents;
 554                unsigned relevant_change, irrelevant_change;
 555
 556                st = lookup_decoration(&revs->treesame, &commit->object);
 557                if (!st)
 558                        die("update_treesame %s", oid_to_hex(&commit->object.oid));
 559                relevant_parents = 0;
 560                relevant_change = irrelevant_change = 0;
 561                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 562                        if (relevant_commit(p->item)) {
 563                                relevant_change |= !st->treesame[n];
 564                                relevant_parents++;
 565                        } else
 566                                irrelevant_change |= !st->treesame[n];
 567                }
 568                if (relevant_parents ? relevant_change : irrelevant_change)
 569                        commit->object.flags &= ~TREESAME;
 570                else
 571                        commit->object.flags |= TREESAME;
 572        }
 573
 574        return commit->object.flags & TREESAME;
 575}
 576
 577static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 578{
 579        /*
 580         * TREESAME is irrelevant unless prune && dense;
 581         * if simplify_history is set, we can't have a mixture of TREESAME and
 582         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 583         *    decoration anyway);
 584         * if first_parent_only is set, then the TREESAME flag is locked
 585         *    against the first parent (and again we lack treesame[] decoration).
 586         */
 587        return revs->prune && revs->dense &&
 588               !revs->simplify_history &&
 589               !revs->first_parent_only;
 590}
 591
 592static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 593{
 594        struct commit_list **pp, *parent;
 595        struct treesame_state *ts = NULL;
 596        int relevant_change = 0, irrelevant_change = 0;
 597        int relevant_parents, nth_parent;
 598
 599        /*
 600         * If we don't do pruning, everything is interesting
 601         */
 602        if (!revs->prune)
 603                return;
 604
 605        if (!commit->tree)
 606                return;
 607
 608        if (!commit->parents) {
 609                if (rev_same_tree_as_empty(revs, commit))
 610                        commit->object.flags |= TREESAME;
 611                return;
 612        }
 613
 614        /*
 615         * Normal non-merge commit? If we don't want to make the
 616         * history dense, we consider it always to be a change..
 617         */
 618        if (!revs->dense && !commit->parents->next)
 619                return;
 620
 621        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 622             (parent = *pp) != NULL;
 623             pp = &parent->next, nth_parent++) {
 624                struct commit *p = parent->item;
 625                if (relevant_commit(p))
 626                        relevant_parents++;
 627
 628                if (nth_parent == 1) {
 629                        /*
 630                         * This our second loop iteration - so we now know
 631                         * we're dealing with a merge.
 632                         *
 633                         * Do not compare with later parents when we care only about
 634                         * the first parent chain, in order to avoid derailing the
 635                         * traversal to follow a side branch that brought everything
 636                         * in the path we are limited to by the pathspec.
 637                         */
 638                        if (revs->first_parent_only)
 639                                break;
 640                        /*
 641                         * If this will remain a potentially-simplifiable
 642                         * merge, remember per-parent treesame if needed.
 643                         * Initialise the array with the comparison from our
 644                         * first iteration.
 645                         */
 646                        if (revs->treesame.name &&
 647                            !revs->simplify_history &&
 648                            !(commit->object.flags & UNINTERESTING)) {
 649                                ts = initialise_treesame(revs, commit);
 650                                if (!(irrelevant_change || relevant_change))
 651                                        ts->treesame[0] = 1;
 652                        }
 653                }
 654                if (parse_commit(p) < 0)
 655                        die("cannot simplify commit %s (because of %s)",
 656                            oid_to_hex(&commit->object.oid),
 657                            oid_to_hex(&p->object.oid));
 658                switch (rev_compare_tree(revs, p, commit)) {
 659                case REV_TREE_SAME:
 660                        if (!revs->simplify_history || !relevant_commit(p)) {
 661                                /* Even if a merge with an uninteresting
 662                                 * side branch brought the entire change
 663                                 * we are interested in, we do not want
 664                                 * to lose the other branches of this
 665                                 * merge, so we just keep going.
 666                                 */
 667                                if (ts)
 668                                        ts->treesame[nth_parent] = 1;
 669                                continue;
 670                        }
 671                        parent->next = NULL;
 672                        commit->parents = parent;
 673                        commit->object.flags |= TREESAME;
 674                        return;
 675
 676                case REV_TREE_NEW:
 677                        if (revs->remove_empty_trees &&
 678                            rev_same_tree_as_empty(revs, p)) {
 679                                /* We are adding all the specified
 680                                 * paths from this parent, so the
 681                                 * history beyond this parent is not
 682                                 * interesting.  Remove its parents
 683                                 * (they are grandparents for us).
 684                                 * IOW, we pretend this parent is a
 685                                 * "root" commit.
 686                                 */
 687                                if (parse_commit(p) < 0)
 688                                        die("cannot simplify commit %s (invalid %s)",
 689                                            oid_to_hex(&commit->object.oid),
 690                                            oid_to_hex(&p->object.oid));
 691                                p->parents = NULL;
 692                        }
 693                /* fallthrough */
 694                case REV_TREE_OLD:
 695                case REV_TREE_DIFFERENT:
 696                        if (relevant_commit(p))
 697                                relevant_change = 1;
 698                        else
 699                                irrelevant_change = 1;
 700                        continue;
 701                }
 702                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
 703        }
 704
 705        /*
 706         * TREESAME is straightforward for single-parent commits. For merge
 707         * commits, it is most useful to define it so that "irrelevant"
 708         * parents cannot make us !TREESAME - if we have any relevant
 709         * parents, then we only consider TREESAMEness with respect to them,
 710         * allowing irrelevant merges from uninteresting branches to be
 711         * simplified away. Only if we have only irrelevant parents do we
 712         * base TREESAME on them. Note that this logic is replicated in
 713         * update_treesame, which should be kept in sync.
 714         */
 715        if (relevant_parents ? !relevant_change : !irrelevant_change)
 716                commit->object.flags |= TREESAME;
 717}
 718
 719static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 720                    struct commit_list *cached_base, struct commit_list **cache)
 721{
 722        struct commit_list *new_entry;
 723
 724        if (cached_base && p->date < cached_base->item->date)
 725                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 726        else
 727                new_entry = commit_list_insert_by_date(p, head);
 728
 729        if (cache && (!*cache || p->date < (*cache)->item->date))
 730                *cache = new_entry;
 731}
 732
 733static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 734                    struct commit_list **list, struct commit_list **cache_ptr)
 735{
 736        struct commit_list *parent = commit->parents;
 737        unsigned left_flag;
 738        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 739
 740        if (commit->object.flags & ADDED)
 741                return 0;
 742        commit->object.flags |= ADDED;
 743
 744        if (revs->include_check &&
 745            !revs->include_check(commit, revs->include_check_data))
 746                return 0;
 747
 748        /*
 749         * If the commit is uninteresting, don't try to
 750         * prune parents - we want the maximal uninteresting
 751         * set.
 752         *
 753         * Normally we haven't parsed the parent
 754         * yet, so we won't have a parent of a parent
 755         * here. However, it may turn out that we've
 756         * reached this commit some other way (where it
 757         * wasn't uninteresting), in which case we need
 758         * to mark its parents recursively too..
 759         */
 760        if (commit->object.flags & UNINTERESTING) {
 761                while (parent) {
 762                        struct commit *p = parent->item;
 763                        parent = parent->next;
 764                        if (p)
 765                                p->object.flags |= UNINTERESTING;
 766                        if (parse_commit_gently(p, 1) < 0)
 767                                continue;
 768                        if (p->parents)
 769                                mark_parents_uninteresting(p);
 770                        if (p->object.flags & SEEN)
 771                                continue;
 772                        p->object.flags |= SEEN;
 773                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 774                }
 775                return 0;
 776        }
 777
 778        /*
 779         * Ok, the commit wasn't uninteresting. Try to
 780         * simplify the commit history and find the parent
 781         * that has no differences in the path set if one exists.
 782         */
 783        try_to_simplify_commit(revs, commit);
 784
 785        if (revs->no_walk)
 786                return 0;
 787
 788        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 789
 790        for (parent = commit->parents; parent; parent = parent->next) {
 791                struct commit *p = parent->item;
 792
 793                if (parse_commit_gently(p, revs->ignore_missing_links) < 0)
 794                        return -1;
 795                if (revs->show_source && !p->util)
 796                        p->util = commit->util;
 797                p->object.flags |= left_flag;
 798                if (!(p->object.flags & SEEN)) {
 799                        p->object.flags |= SEEN;
 800                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 801                }
 802                if (revs->first_parent_only)
 803                        break;
 804        }
 805        return 0;
 806}
 807
 808static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 809{
 810        struct commit_list *p;
 811        int left_count = 0, right_count = 0;
 812        int left_first;
 813        struct patch_ids ids;
 814        unsigned cherry_flag;
 815
 816        /* First count the commits on the left and on the right */
 817        for (p = list; p; p = p->next) {
 818                struct commit *commit = p->item;
 819                unsigned flags = commit->object.flags;
 820                if (flags & BOUNDARY)
 821                        ;
 822                else if (flags & SYMMETRIC_LEFT)
 823                        left_count++;
 824                else
 825                        right_count++;
 826        }
 827
 828        if (!left_count || !right_count)
 829                return;
 830
 831        left_first = left_count < right_count;
 832        init_patch_ids(&ids);
 833        ids.diffopts.pathspec = revs->diffopt.pathspec;
 834
 835        /* Compute patch-ids for one side */
 836        for (p = list; p; p = p->next) {
 837                struct commit *commit = p->item;
 838                unsigned flags = commit->object.flags;
 839
 840                if (flags & BOUNDARY)
 841                        continue;
 842                /*
 843                 * If we have fewer left, left_first is set and we omit
 844                 * commits on the right branch in this loop.  If we have
 845                 * fewer right, we skip the left ones.
 846                 */
 847                if (left_first != !!(flags & SYMMETRIC_LEFT))
 848                        continue;
 849                add_commit_patch_id(commit, &ids);
 850        }
 851
 852        /* either cherry_mark or cherry_pick are true */
 853        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 854
 855        /* Check the other side */
 856        for (p = list; p; p = p->next) {
 857                struct commit *commit = p->item;
 858                struct patch_id *id;
 859                unsigned flags = commit->object.flags;
 860
 861                if (flags & BOUNDARY)
 862                        continue;
 863                /*
 864                 * If we have fewer left, left_first is set and we omit
 865                 * commits on the left branch in this loop.
 866                 */
 867                if (left_first == !!(flags & SYMMETRIC_LEFT))
 868                        continue;
 869
 870                /*
 871                 * Have we seen the same patch id?
 872                 */
 873                id = has_commit_patch_id(commit, &ids);
 874                if (!id)
 875                        continue;
 876
 877                commit->object.flags |= cherry_flag;
 878                id->commit->object.flags |= cherry_flag;
 879        }
 880
 881        free_patch_ids(&ids);
 882}
 883
 884/* How many extra uninteresting commits we want to see.. */
 885#define SLOP 5
 886
 887static int still_interesting(struct commit_list *src, timestamp_t date, int slop,
 888                             struct commit **interesting_cache)
 889{
 890        /*
 891         * No source list at all? We're definitely done..
 892         */
 893        if (!src)
 894                return 0;
 895
 896        /*
 897         * Does the destination list contain entries with a date
 898         * before the source list? Definitely _not_ done.
 899         */
 900        if (date <= src->item->date)
 901                return SLOP;
 902
 903        /*
 904         * Does the source list still have interesting commits in
 905         * it? Definitely not done..
 906         */
 907        if (!everybody_uninteresting(src, interesting_cache))
 908                return SLOP;
 909
 910        /* Ok, we're closing in.. */
 911        return slop-1;
 912}
 913
 914/*
 915 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 916 * of B but not ancestors of A but further limits the result to those
 917 * that are descendants of A.  This takes the list of bottom commits and
 918 * the result of "A..B" without --ancestry-path, and limits the latter
 919 * further to the ones that can reach one of the commits in "bottom".
 920 */
 921static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 922{
 923        struct commit_list *p;
 924        struct commit_list *rlist = NULL;
 925        int made_progress;
 926
 927        /*
 928         * Reverse the list so that it will be likely that we would
 929         * process parents before children.
 930         */
 931        for (p = list; p; p = p->next)
 932                commit_list_insert(p->item, &rlist);
 933
 934        for (p = bottom; p; p = p->next)
 935                p->item->object.flags |= TMP_MARK;
 936
 937        /*
 938         * Mark the ones that can reach bottom commits in "list",
 939         * in a bottom-up fashion.
 940         */
 941        do {
 942                made_progress = 0;
 943                for (p = rlist; p; p = p->next) {
 944                        struct commit *c = p->item;
 945                        struct commit_list *parents;
 946                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 947                                continue;
 948                        for (parents = c->parents;
 949                             parents;
 950                             parents = parents->next) {
 951                                if (!(parents->item->object.flags & TMP_MARK))
 952                                        continue;
 953                                c->object.flags |= TMP_MARK;
 954                                made_progress = 1;
 955                                break;
 956                        }
 957                }
 958        } while (made_progress);
 959
 960        /*
 961         * NEEDSWORK: decide if we want to remove parents that are
 962         * not marked with TMP_MARK from commit->parents for commits
 963         * in the resulting list.  We may not want to do that, though.
 964         */
 965
 966        /*
 967         * The ones that are not marked with TMP_MARK are uninteresting
 968         */
 969        for (p = list; p; p = p->next) {
 970                struct commit *c = p->item;
 971                if (c->object.flags & TMP_MARK)
 972                        continue;
 973                c->object.flags |= UNINTERESTING;
 974        }
 975
 976        /* We are done with the TMP_MARK */
 977        for (p = list; p; p = p->next)
 978                p->item->object.flags &= ~TMP_MARK;
 979        for (p = bottom; p; p = p->next)
 980                p->item->object.flags &= ~TMP_MARK;
 981        free_commit_list(rlist);
 982}
 983
 984/*
 985 * Before walking the history, keep the set of "negative" refs the
 986 * caller has asked to exclude.
 987 *
 988 * This is used to compute "rev-list --ancestry-path A..B", as we need
 989 * to filter the result of "A..B" further to the ones that can actually
 990 * reach A.
 991 */
 992static struct commit_list *collect_bottom_commits(struct commit_list *list)
 993{
 994        struct commit_list *elem, *bottom = NULL;
 995        for (elem = list; elem; elem = elem->next)
 996                if (elem->item->object.flags & BOTTOM)
 997                        commit_list_insert(elem->item, &bottom);
 998        return bottom;
 999}
1000
1001/* Assumes either left_only or right_only is set */
1002static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1003{
1004        struct commit_list *p;
1005
1006        for (p = list; p; p = p->next) {
1007                struct commit *commit = p->item;
1008
1009                if (revs->right_only) {
1010                        if (commit->object.flags & SYMMETRIC_LEFT)
1011                                commit->object.flags |= SHOWN;
1012                } else  /* revs->left_only is set */
1013                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1014                                commit->object.flags |= SHOWN;
1015        }
1016}
1017
1018static int limit_list(struct rev_info *revs)
1019{
1020        int slop = SLOP;
1021        timestamp_t date = TIME_MAX;
1022        struct commit_list *list = revs->commits;
1023        struct commit_list *newlist = NULL;
1024        struct commit_list **p = &newlist;
1025        struct commit_list *bottom = NULL;
1026        struct commit *interesting_cache = NULL;
1027
1028        if (revs->ancestry_path) {
1029                bottom = collect_bottom_commits(list);
1030                if (!bottom)
1031                        die("--ancestry-path given but there are no bottom commits");
1032        }
1033
1034        while (list) {
1035                struct commit *commit = pop_commit(&list);
1036                struct object *obj = &commit->object;
1037                show_early_output_fn_t show;
1038
1039                if (commit == interesting_cache)
1040                        interesting_cache = NULL;
1041
1042                if (revs->max_age != -1 && (commit->date < revs->max_age))
1043                        obj->flags |= UNINTERESTING;
1044                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1045                        return -1;
1046                if (obj->flags & UNINTERESTING) {
1047                        mark_parents_uninteresting(commit);
1048                        if (revs->show_all)
1049                                p = &commit_list_insert(commit, p)->next;
1050                        slop = still_interesting(list, date, slop, &interesting_cache);
1051                        if (slop)
1052                                continue;
1053                        /* If showing all, add the whole pending list to the end */
1054                        if (revs->show_all)
1055                                *p = list;
1056                        break;
1057                }
1058                if (revs->min_age != -1 && (commit->date > revs->min_age))
1059                        continue;
1060                date = commit->date;
1061                p = &commit_list_insert(commit, p)->next;
1062
1063                show = show_early_output;
1064                if (!show)
1065                        continue;
1066
1067                show(revs, newlist);
1068                show_early_output = NULL;
1069        }
1070        if (revs->cherry_pick || revs->cherry_mark)
1071                cherry_pick_list(newlist, revs);
1072
1073        if (revs->left_only || revs->right_only)
1074                limit_left_right(newlist, revs);
1075
1076        if (bottom) {
1077                limit_to_ancestry(bottom, newlist);
1078                free_commit_list(bottom);
1079        }
1080
1081        /*
1082         * Check if any commits have become TREESAME by some of their parents
1083         * becoming UNINTERESTING.
1084         */
1085        if (limiting_can_increase_treesame(revs))
1086                for (list = newlist; list; list = list->next) {
1087                        struct commit *c = list->item;
1088                        if (c->object.flags & (UNINTERESTING | TREESAME))
1089                                continue;
1090                        update_treesame(revs, c);
1091                }
1092
1093        revs->commits = newlist;
1094        return 0;
1095}
1096
1097/*
1098 * Add an entry to refs->cmdline with the specified information.
1099 * *name is copied.
1100 */
1101static void add_rev_cmdline(struct rev_info *revs,
1102                            struct object *item,
1103                            const char *name,
1104                            int whence,
1105                            unsigned flags)
1106{
1107        struct rev_cmdline_info *info = &revs->cmdline;
1108        int nr = info->nr;
1109
1110        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1111        info->rev[nr].item = item;
1112        info->rev[nr].name = xstrdup(name);
1113        info->rev[nr].whence = whence;
1114        info->rev[nr].flags = flags;
1115        info->nr++;
1116}
1117
1118static void add_rev_cmdline_list(struct rev_info *revs,
1119                                 struct commit_list *commit_list,
1120                                 int whence,
1121                                 unsigned flags)
1122{
1123        while (commit_list) {
1124                struct object *object = &commit_list->item->object;
1125                add_rev_cmdline(revs, object, oid_to_hex(&object->oid),
1126                                whence, flags);
1127                commit_list = commit_list->next;
1128        }
1129}
1130
1131struct all_refs_cb {
1132        int all_flags;
1133        int warned_bad_reflog;
1134        struct rev_info *all_revs;
1135        const char *name_for_errormsg;
1136        struct ref_store *refs;
1137};
1138
1139int ref_excluded(struct string_list *ref_excludes, const char *path)
1140{
1141        struct string_list_item *item;
1142
1143        if (!ref_excludes)
1144                return 0;
1145        for_each_string_list_item(item, ref_excludes) {
1146                if (!wildmatch(item->string, path, 0))
1147                        return 1;
1148        }
1149        return 0;
1150}
1151
1152static int handle_one_ref(const char *path, const struct object_id *oid,
1153                          int flag, void *cb_data)
1154{
1155        struct all_refs_cb *cb = cb_data;
1156        struct object *object;
1157
1158        if (ref_excluded(cb->all_revs->ref_excludes, path))
1159            return 0;
1160
1161        object = get_reference(cb->all_revs, path, oid, cb->all_flags);
1162        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1163        add_pending_oid(cb->all_revs, path, oid, cb->all_flags);
1164        return 0;
1165}
1166
1167static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1168        unsigned flags)
1169{
1170        cb->all_revs = revs;
1171        cb->all_flags = flags;
1172        revs->rev_input_given = 1;
1173        cb->refs = NULL;
1174}
1175
1176void clear_ref_exclusion(struct string_list **ref_excludes_p)
1177{
1178        if (*ref_excludes_p) {
1179                string_list_clear(*ref_excludes_p, 0);
1180                free(*ref_excludes_p);
1181        }
1182        *ref_excludes_p = NULL;
1183}
1184
1185void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1186{
1187        if (!*ref_excludes_p) {
1188                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1189                (*ref_excludes_p)->strdup_strings = 1;
1190        }
1191        string_list_append(*ref_excludes_p, exclude);
1192}
1193
1194static void handle_refs(struct ref_store *refs,
1195                        struct rev_info *revs, unsigned flags,
1196                        int (*for_each)(struct ref_store *, each_ref_fn, void *))
1197{
1198        struct all_refs_cb cb;
1199
1200        if (!refs) {
1201                /* this could happen with uninitialized submodules */
1202                return;
1203        }
1204
1205        init_all_refs_cb(&cb, revs, flags);
1206        for_each(refs, handle_one_ref, &cb);
1207}
1208
1209static void handle_one_reflog_commit(struct object_id *oid, void *cb_data)
1210{
1211        struct all_refs_cb *cb = cb_data;
1212        if (!is_null_oid(oid)) {
1213                struct object *o = parse_object(oid);
1214                if (o) {
1215                        o->flags |= cb->all_flags;
1216                        /* ??? CMDLINEFLAGS ??? */
1217                        add_pending_object(cb->all_revs, o, "");
1218                }
1219                else if (!cb->warned_bad_reflog) {
1220                        warning("reflog of '%s' references pruned commits",
1221                                cb->name_for_errormsg);
1222                        cb->warned_bad_reflog = 1;
1223                }
1224        }
1225}
1226
1227static int handle_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
1228                const char *email, timestamp_t timestamp, int tz,
1229                const char *message, void *cb_data)
1230{
1231        handle_one_reflog_commit(ooid, cb_data);
1232        handle_one_reflog_commit(noid, cb_data);
1233        return 0;
1234}
1235
1236static int handle_one_reflog(const char *path, const struct object_id *oid,
1237                             int flag, void *cb_data)
1238{
1239        struct all_refs_cb *cb = cb_data;
1240        cb->warned_bad_reflog = 0;
1241        cb->name_for_errormsg = path;
1242        refs_for_each_reflog_ent(cb->refs, path,
1243                                 handle_one_reflog_ent, cb_data);
1244        return 0;
1245}
1246
1247static void add_other_reflogs_to_pending(struct all_refs_cb *cb)
1248{
1249        struct worktree **worktrees, **p;
1250
1251        worktrees = get_worktrees(0);
1252        for (p = worktrees; *p; p++) {
1253                struct worktree *wt = *p;
1254
1255                if (wt->is_current)
1256                        continue;
1257
1258                cb->refs = get_worktree_ref_store(wt);
1259                refs_for_each_reflog(cb->refs,
1260                                     handle_one_reflog,
1261                                     cb);
1262        }
1263        free_worktrees(worktrees);
1264}
1265
1266void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1267{
1268        struct all_refs_cb cb;
1269
1270        cb.all_revs = revs;
1271        cb.all_flags = flags;
1272        cb.refs = get_main_ref_store();
1273        for_each_reflog(handle_one_reflog, &cb);
1274
1275        if (!revs->single_worktree)
1276                add_other_reflogs_to_pending(&cb);
1277}
1278
1279static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1280                           struct strbuf *path)
1281{
1282        size_t baselen = path->len;
1283        int i;
1284
1285        if (it->entry_count >= 0) {
1286                struct tree *tree = lookup_tree(&it->oid);
1287                add_pending_object_with_path(revs, &tree->object, "",
1288                                             040000, path->buf);
1289        }
1290
1291        for (i = 0; i < it->subtree_nr; i++) {
1292                struct cache_tree_sub *sub = it->down[i];
1293                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1294                add_cache_tree(sub->cache_tree, revs, path);
1295                strbuf_setlen(path, baselen);
1296        }
1297
1298}
1299
1300static void do_add_index_objects_to_pending(struct rev_info *revs,
1301                                            struct index_state *istate)
1302{
1303        int i;
1304
1305        for (i = 0; i < istate->cache_nr; i++) {
1306                struct cache_entry *ce = istate->cache[i];
1307                struct blob *blob;
1308
1309                if (S_ISGITLINK(ce->ce_mode))
1310                        continue;
1311
1312                blob = lookup_blob(&ce->oid);
1313                if (!blob)
1314                        die("unable to add index blob to traversal");
1315                add_pending_object_with_path(revs, &blob->object, "",
1316                                             ce->ce_mode, ce->name);
1317        }
1318
1319        if (istate->cache_tree) {
1320                struct strbuf path = STRBUF_INIT;
1321                add_cache_tree(istate->cache_tree, revs, &path);
1322                strbuf_release(&path);
1323        }
1324}
1325
1326void add_index_objects_to_pending(struct rev_info *revs, unsigned int flags)
1327{
1328        struct worktree **worktrees, **p;
1329
1330        read_cache();
1331        do_add_index_objects_to_pending(revs, &the_index);
1332
1333        if (revs->single_worktree)
1334                return;
1335
1336        worktrees = get_worktrees(0);
1337        for (p = worktrees; *p; p++) {
1338                struct worktree *wt = *p;
1339                struct index_state istate = { NULL };
1340
1341                if (wt->is_current)
1342                        continue; /* current index already taken care of */
1343
1344                if (read_index_from(&istate,
1345                                    worktree_git_path(wt, "index")) > 0)
1346                        do_add_index_objects_to_pending(revs, &istate);
1347                discard_index(&istate);
1348        }
1349        free_worktrees(worktrees);
1350}
1351
1352static int add_parents_only(struct rev_info *revs, const char *arg_, int flags,
1353                            int exclude_parent)
1354{
1355        struct object_id oid;
1356        struct object *it;
1357        struct commit *commit;
1358        struct commit_list *parents;
1359        int parent_number;
1360        const char *arg = arg_;
1361
1362        if (*arg == '^') {
1363                flags ^= UNINTERESTING | BOTTOM;
1364                arg++;
1365        }
1366        if (get_oid_committish(arg, &oid))
1367                return 0;
1368        while (1) {
1369                it = get_reference(revs, arg, &oid, 0);
1370                if (!it && revs->ignore_missing)
1371                        return 0;
1372                if (it->type != OBJ_TAG)
1373                        break;
1374                if (!((struct tag*)it)->tagged)
1375                        return 0;
1376                oidcpy(&oid, &((struct tag*)it)->tagged->oid);
1377        }
1378        if (it->type != OBJ_COMMIT)
1379                return 0;
1380        commit = (struct commit *)it;
1381        if (exclude_parent &&
1382            exclude_parent > commit_list_count(commit->parents))
1383                return 0;
1384        for (parents = commit->parents, parent_number = 1;
1385             parents;
1386             parents = parents->next, parent_number++) {
1387                if (exclude_parent && parent_number != exclude_parent)
1388                        continue;
1389
1390                it = &parents->item->object;
1391                it->flags |= flags;
1392                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1393                add_pending_object(revs, it, arg);
1394        }
1395        return 1;
1396}
1397
1398void init_revisions(struct rev_info *revs, const char *prefix)
1399{
1400        memset(revs, 0, sizeof(*revs));
1401
1402        revs->abbrev = DEFAULT_ABBREV;
1403        revs->ignore_merges = 1;
1404        revs->simplify_history = 1;
1405        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
1406        DIFF_OPT_SET(&revs->pruning, QUICK);
1407        revs->pruning.add_remove = file_add_remove;
1408        revs->pruning.change = file_change;
1409        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1410        revs->dense = 1;
1411        revs->prefix = prefix;
1412        revs->max_age = -1;
1413        revs->min_age = -1;
1414        revs->skip_count = -1;
1415        revs->max_count = -1;
1416        revs->max_parents = -1;
1417        revs->expand_tabs_in_log = -1;
1418
1419        revs->commit_format = CMIT_FMT_DEFAULT;
1420        revs->expand_tabs_in_log_default = 8;
1421
1422        init_grep_defaults();
1423        grep_init(&revs->grep_filter, prefix);
1424        revs->grep_filter.status_only = 1;
1425
1426        diff_setup(&revs->diffopt);
1427        if (prefix && !revs->diffopt.prefix) {
1428                revs->diffopt.prefix = prefix;
1429                revs->diffopt.prefix_length = strlen(prefix);
1430        }
1431
1432        revs->notes_opt.use_default_notes = -1;
1433}
1434
1435static void add_pending_commit_list(struct rev_info *revs,
1436                                    struct commit_list *commit_list,
1437                                    unsigned int flags)
1438{
1439        while (commit_list) {
1440                struct object *object = &commit_list->item->object;
1441                object->flags |= flags;
1442                add_pending_object(revs, object, oid_to_hex(&object->oid));
1443                commit_list = commit_list->next;
1444        }
1445}
1446
1447static void prepare_show_merge(struct rev_info *revs)
1448{
1449        struct commit_list *bases;
1450        struct commit *head, *other;
1451        struct object_id oid;
1452        const char **prune = NULL;
1453        int i, prune_num = 1; /* counting terminating NULL */
1454
1455        if (get_oid("HEAD", &oid))
1456                die("--merge without HEAD?");
1457        head = lookup_commit_or_die(&oid, "HEAD");
1458        if (get_oid("MERGE_HEAD", &oid))
1459                die("--merge without MERGE_HEAD?");
1460        other = lookup_commit_or_die(&oid, "MERGE_HEAD");
1461        add_pending_object(revs, &head->object, "HEAD");
1462        add_pending_object(revs, &other->object, "MERGE_HEAD");
1463        bases = get_merge_bases(head, other);
1464        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1465        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1466        free_commit_list(bases);
1467        head->object.flags |= SYMMETRIC_LEFT;
1468
1469        if (!active_nr)
1470                read_cache();
1471        for (i = 0; i < active_nr; i++) {
1472                const struct cache_entry *ce = active_cache[i];
1473                if (!ce_stage(ce))
1474                        continue;
1475                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1476                        prune_num++;
1477                        REALLOC_ARRAY(prune, prune_num);
1478                        prune[prune_num-2] = ce->name;
1479                        prune[prune_num-1] = NULL;
1480                }
1481                while ((i+1 < active_nr) &&
1482                       ce_same_name(ce, active_cache[i+1]))
1483                        i++;
1484        }
1485        clear_pathspec(&revs->prune_data);
1486        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1487                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1488        revs->limited = 1;
1489}
1490
1491static int dotdot_missing(const char *arg, char *dotdot,
1492                          struct rev_info *revs, int symmetric)
1493{
1494        if (revs->ignore_missing)
1495                return 0;
1496        /* de-munge so we report the full argument */
1497        *dotdot = '.';
1498        die(symmetric
1499            ? "Invalid symmetric difference expression %s"
1500            : "Invalid revision range %s", arg);
1501}
1502
1503static int handle_dotdot_1(const char *arg, char *dotdot,
1504                           struct rev_info *revs, int flags,
1505                           int cant_be_filename,
1506                           struct object_context *a_oc,
1507                           struct object_context *b_oc)
1508{
1509        const char *a_name, *b_name;
1510        struct object_id a_oid, b_oid;
1511        struct object *a_obj, *b_obj;
1512        unsigned int a_flags, b_flags;
1513        int symmetric = 0;
1514        unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1515        unsigned int oc_flags = GET_OID_COMMITTISH | GET_OID_RECORD_PATH;
1516
1517        a_name = arg;
1518        if (!*a_name)
1519                a_name = "HEAD";
1520
1521        b_name = dotdot + 2;
1522        if (*b_name == '.') {
1523                symmetric = 1;
1524                b_name++;
1525        }
1526        if (!*b_name)
1527                b_name = "HEAD";
1528
1529        if (get_oid_with_context(a_name, oc_flags, &a_oid, a_oc) ||
1530            get_oid_with_context(b_name, oc_flags, &b_oid, b_oc))
1531                return -1;
1532
1533        if (!cant_be_filename) {
1534                *dotdot = '.';
1535                verify_non_filename(revs->prefix, arg);
1536                *dotdot = '\0';
1537        }
1538
1539        a_obj = parse_object(&a_oid);
1540        b_obj = parse_object(&b_oid);
1541        if (!a_obj || !b_obj)
1542                return dotdot_missing(arg, dotdot, revs, symmetric);
1543
1544        if (!symmetric) {
1545                /* just A..B */
1546                b_flags = flags;
1547                a_flags = flags_exclude;
1548        } else {
1549                /* A...B -- find merge bases between the two */
1550                struct commit *a, *b;
1551                struct commit_list *exclude;
1552
1553                a = lookup_commit_reference(&a_obj->oid);
1554                b = lookup_commit_reference(&b_obj->oid);
1555                if (!a || !b)
1556                        return dotdot_missing(arg, dotdot, revs, symmetric);
1557
1558                exclude = get_merge_bases(a, b);
1559                add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
1560                                     flags_exclude);
1561                add_pending_commit_list(revs, exclude, flags_exclude);
1562                free_commit_list(exclude);
1563
1564                b_flags = flags;
1565                a_flags = flags | SYMMETRIC_LEFT;
1566        }
1567
1568        a_obj->flags |= a_flags;
1569        b_obj->flags |= b_flags;
1570        add_rev_cmdline(revs, a_obj, a_name, REV_CMD_LEFT, a_flags);
1571        add_rev_cmdline(revs, b_obj, b_name, REV_CMD_RIGHT, b_flags);
1572        add_pending_object_with_path(revs, a_obj, a_name, a_oc->mode, a_oc->path);
1573        add_pending_object_with_path(revs, b_obj, b_name, b_oc->mode, b_oc->path);
1574        return 0;
1575}
1576
1577static int handle_dotdot(const char *arg,
1578                         struct rev_info *revs, int flags,
1579                         int cant_be_filename)
1580{
1581        struct object_context a_oc, b_oc;
1582        char *dotdot = strstr(arg, "..");
1583        int ret;
1584
1585        if (!dotdot)
1586                return -1;
1587
1588        memset(&a_oc, 0, sizeof(a_oc));
1589        memset(&b_oc, 0, sizeof(b_oc));
1590
1591        *dotdot = '\0';
1592        ret = handle_dotdot_1(arg, dotdot, revs, flags, cant_be_filename,
1593                              &a_oc, &b_oc);
1594        *dotdot = '.';
1595
1596        free(a_oc.path);
1597        free(b_oc.path);
1598
1599        return ret;
1600}
1601
1602int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1603{
1604        struct object_context oc;
1605        char *mark;
1606        struct object *object;
1607        struct object_id oid;
1608        int local_flags;
1609        const char *arg = arg_;
1610        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1611        unsigned get_sha1_flags = GET_OID_RECORD_PATH;
1612
1613        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1614
1615        if (!cant_be_filename && !strcmp(arg, "..")) {
1616                /*
1617                 * Just ".."?  That is not a range but the
1618                 * pathspec for the parent directory.
1619                 */
1620                return -1;
1621        }
1622
1623        if (!handle_dotdot(arg, revs, flags, revarg_opt))
1624                return 0;
1625
1626        mark = strstr(arg, "^@");
1627        if (mark && !mark[2]) {
1628                *mark = 0;
1629                if (add_parents_only(revs, arg, flags, 0))
1630                        return 0;
1631                *mark = '^';
1632        }
1633        mark = strstr(arg, "^!");
1634        if (mark && !mark[2]) {
1635                *mark = 0;
1636                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), 0))
1637                        *mark = '^';
1638        }
1639        mark = strstr(arg, "^-");
1640        if (mark) {
1641                int exclude_parent = 1;
1642
1643                if (mark[2]) {
1644                        char *end;
1645                        exclude_parent = strtoul(mark + 2, &end, 10);
1646                        if (*end != '\0' || !exclude_parent)
1647                                return -1;
1648                }
1649
1650                *mark = 0;
1651                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM), exclude_parent))
1652                        *mark = '^';
1653        }
1654
1655        local_flags = 0;
1656        if (*arg == '^') {
1657                local_flags = UNINTERESTING | BOTTOM;
1658                arg++;
1659        }
1660
1661        if (revarg_opt & REVARG_COMMITTISH)
1662                get_sha1_flags |= GET_OID_COMMITTISH;
1663
1664        if (get_oid_with_context(arg, get_sha1_flags, &oid, &oc))
1665                return revs->ignore_missing ? 0 : -1;
1666        if (!cant_be_filename)
1667                verify_non_filename(revs->prefix, arg);
1668        object = get_reference(revs, arg, &oid, flags ^ local_flags);
1669        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1670        add_pending_object_with_path(revs, object, arg, oc.mode, oc.path);
1671        free(oc.path);
1672        return 0;
1673}
1674
1675struct cmdline_pathspec {
1676        int alloc;
1677        int nr;
1678        const char **path;
1679};
1680
1681static void append_prune_data(struct cmdline_pathspec *prune, const char **av)
1682{
1683        while (*av) {
1684                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1685                prune->path[prune->nr++] = *(av++);
1686        }
1687}
1688
1689static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1690                                     struct cmdline_pathspec *prune)
1691{
1692        while (strbuf_getline(sb, stdin) != EOF) {
1693                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1694                prune->path[prune->nr++] = xstrdup(sb->buf);
1695        }
1696}
1697
1698static void read_revisions_from_stdin(struct rev_info *revs,
1699                                      struct cmdline_pathspec *prune)
1700{
1701        struct strbuf sb;
1702        int seen_dashdash = 0;
1703        int save_warning;
1704
1705        save_warning = warn_on_object_refname_ambiguity;
1706        warn_on_object_refname_ambiguity = 0;
1707
1708        strbuf_init(&sb, 1000);
1709        while (strbuf_getline(&sb, stdin) != EOF) {
1710                int len = sb.len;
1711                if (!len)
1712                        break;
1713                if (sb.buf[0] == '-') {
1714                        if (len == 2 && sb.buf[1] == '-') {
1715                                seen_dashdash = 1;
1716                                break;
1717                        }
1718                        die("options not supported in --stdin mode");
1719                }
1720                if (handle_revision_arg(sb.buf, revs, 0,
1721                                        REVARG_CANNOT_BE_FILENAME))
1722                        die("bad revision '%s'", sb.buf);
1723        }
1724        if (seen_dashdash)
1725                read_pathspec_from_stdin(revs, &sb, prune);
1726
1727        strbuf_release(&sb);
1728        warn_on_object_refname_ambiguity = save_warning;
1729}
1730
1731static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1732{
1733        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1734}
1735
1736static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1737{
1738        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1739}
1740
1741static void add_message_grep(struct rev_info *revs, const char *pattern)
1742{
1743        add_grep(revs, pattern, GREP_PATTERN_BODY);
1744}
1745
1746static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1747                               int *unkc, const char **unkv)
1748{
1749        const char *arg = argv[0];
1750        const char *optarg;
1751        int argcount;
1752
1753        /* pseudo revision arguments */
1754        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1755            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1756            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1757            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1758            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1759            !strcmp(arg, "--indexed-objects") ||
1760            starts_with(arg, "--exclude=") ||
1761            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1762            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1763        {
1764                unkv[(*unkc)++] = arg;
1765                return 1;
1766        }
1767
1768        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1769                revs->max_count = atoi(optarg);
1770                revs->no_walk = 0;
1771                return argcount;
1772        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1773                revs->skip_count = atoi(optarg);
1774                return argcount;
1775        } else if ((*arg == '-') && isdigit(arg[1])) {
1776                /* accept -<digit>, like traditional "head" */
1777                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1778                    revs->max_count < 0)
1779                        die("'%s': not a non-negative integer", arg + 1);
1780                revs->no_walk = 0;
1781        } else if (!strcmp(arg, "-n")) {
1782                if (argc <= 1)
1783                        return error("-n requires an argument");
1784                revs->max_count = atoi(argv[1]);
1785                revs->no_walk = 0;
1786                return 2;
1787        } else if (skip_prefix(arg, "-n", &optarg)) {
1788                revs->max_count = atoi(optarg);
1789                revs->no_walk = 0;
1790        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1791                revs->max_age = atoi(optarg);
1792                return argcount;
1793        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1794                revs->max_age = approxidate(optarg);
1795                return argcount;
1796        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1797                revs->max_age = approxidate(optarg);
1798                return argcount;
1799        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1800                revs->min_age = atoi(optarg);
1801                return argcount;
1802        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1803                revs->min_age = approxidate(optarg);
1804                return argcount;
1805        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1806                revs->min_age = approxidate(optarg);
1807                return argcount;
1808        } else if (!strcmp(arg, "--first-parent")) {
1809                revs->first_parent_only = 1;
1810        } else if (!strcmp(arg, "--ancestry-path")) {
1811                revs->ancestry_path = 1;
1812                revs->simplify_history = 0;
1813                revs->limited = 1;
1814        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1815                init_reflog_walk(&revs->reflog_info);
1816        } else if (!strcmp(arg, "--default")) {
1817                if (argc <= 1)
1818                        return error("bad --default argument");
1819                revs->def = argv[1];
1820                return 2;
1821        } else if (!strcmp(arg, "--merge")) {
1822                revs->show_merge = 1;
1823        } else if (!strcmp(arg, "--topo-order")) {
1824                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1825                revs->topo_order = 1;
1826        } else if (!strcmp(arg, "--simplify-merges")) {
1827                revs->simplify_merges = 1;
1828                revs->topo_order = 1;
1829                revs->rewrite_parents = 1;
1830                revs->simplify_history = 0;
1831                revs->limited = 1;
1832        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1833                revs->simplify_merges = 1;
1834                revs->topo_order = 1;
1835                revs->rewrite_parents = 1;
1836                revs->simplify_history = 0;
1837                revs->simplify_by_decoration = 1;
1838                revs->limited = 1;
1839                revs->prune = 1;
1840                load_ref_decorations(DECORATE_SHORT_REFS);
1841        } else if (!strcmp(arg, "--date-order")) {
1842                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1843                revs->topo_order = 1;
1844        } else if (!strcmp(arg, "--author-date-order")) {
1845                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1846                revs->topo_order = 1;
1847        } else if (!strcmp(arg, "--early-output")) {
1848                revs->early_output = 100;
1849                revs->topo_order = 1;
1850        } else if (skip_prefix(arg, "--early-output=", &optarg)) {
1851                if (strtoul_ui(optarg, 10, &revs->early_output) < 0)
1852                        die("'%s': not a non-negative integer", optarg);
1853                revs->topo_order = 1;
1854        } else if (!strcmp(arg, "--parents")) {
1855                revs->rewrite_parents = 1;
1856                revs->print_parents = 1;
1857        } else if (!strcmp(arg, "--dense")) {
1858                revs->dense = 1;
1859        } else if (!strcmp(arg, "--sparse")) {
1860                revs->dense = 0;
1861        } else if (!strcmp(arg, "--show-all")) {
1862                revs->show_all = 1;
1863        } else if (!strcmp(arg, "--remove-empty")) {
1864                revs->remove_empty_trees = 1;
1865        } else if (!strcmp(arg, "--merges")) {
1866                revs->min_parents = 2;
1867        } else if (!strcmp(arg, "--no-merges")) {
1868                revs->max_parents = 1;
1869        } else if (skip_prefix(arg, "--min-parents=", &optarg)) {
1870                revs->min_parents = atoi(optarg);
1871        } else if (!strcmp(arg, "--no-min-parents")) {
1872                revs->min_parents = 0;
1873        } else if (skip_prefix(arg, "--max-parents=", &optarg)) {
1874                revs->max_parents = atoi(optarg);
1875        } else if (!strcmp(arg, "--no-max-parents")) {
1876                revs->max_parents = -1;
1877        } else if (!strcmp(arg, "--boundary")) {
1878                revs->boundary = 1;
1879        } else if (!strcmp(arg, "--left-right")) {
1880                revs->left_right = 1;
1881        } else if (!strcmp(arg, "--left-only")) {
1882                if (revs->right_only)
1883                        die("--left-only is incompatible with --right-only"
1884                            " or --cherry");
1885                revs->left_only = 1;
1886        } else if (!strcmp(arg, "--right-only")) {
1887                if (revs->left_only)
1888                        die("--right-only is incompatible with --left-only");
1889                revs->right_only = 1;
1890        } else if (!strcmp(arg, "--cherry")) {
1891                if (revs->left_only)
1892                        die("--cherry is incompatible with --left-only");
1893                revs->cherry_mark = 1;
1894                revs->right_only = 1;
1895                revs->max_parents = 1;
1896                revs->limited = 1;
1897        } else if (!strcmp(arg, "--count")) {
1898                revs->count = 1;
1899        } else if (!strcmp(arg, "--cherry-mark")) {
1900                if (revs->cherry_pick)
1901                        die("--cherry-mark is incompatible with --cherry-pick");
1902                revs->cherry_mark = 1;
1903                revs->limited = 1; /* needs limit_list() */
1904        } else if (!strcmp(arg, "--cherry-pick")) {
1905                if (revs->cherry_mark)
1906                        die("--cherry-pick is incompatible with --cherry-mark");
1907                revs->cherry_pick = 1;
1908                revs->limited = 1;
1909        } else if (!strcmp(arg, "--objects")) {
1910                revs->tag_objects = 1;
1911                revs->tree_objects = 1;
1912                revs->blob_objects = 1;
1913        } else if (!strcmp(arg, "--objects-edge")) {
1914                revs->tag_objects = 1;
1915                revs->tree_objects = 1;
1916                revs->blob_objects = 1;
1917                revs->edge_hint = 1;
1918        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1919                revs->tag_objects = 1;
1920                revs->tree_objects = 1;
1921                revs->blob_objects = 1;
1922                revs->edge_hint = 1;
1923                revs->edge_hint_aggressive = 1;
1924        } else if (!strcmp(arg, "--verify-objects")) {
1925                revs->tag_objects = 1;
1926                revs->tree_objects = 1;
1927                revs->blob_objects = 1;
1928                revs->verify_objects = 1;
1929        } else if (!strcmp(arg, "--unpacked")) {
1930                revs->unpacked = 1;
1931        } else if (starts_with(arg, "--unpacked=")) {
1932                die("--unpacked=<packfile> no longer supported.");
1933        } else if (!strcmp(arg, "-r")) {
1934                revs->diff = 1;
1935                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1936        } else if (!strcmp(arg, "-t")) {
1937                revs->diff = 1;
1938                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1939                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1940        } else if (!strcmp(arg, "-m")) {
1941                revs->ignore_merges = 0;
1942        } else if (!strcmp(arg, "-c")) {
1943                revs->diff = 1;
1944                revs->dense_combined_merges = 0;
1945                revs->combine_merges = 1;
1946        } else if (!strcmp(arg, "--cc")) {
1947                revs->diff = 1;
1948                revs->dense_combined_merges = 1;
1949                revs->combine_merges = 1;
1950        } else if (!strcmp(arg, "-v")) {
1951                revs->verbose_header = 1;
1952        } else if (!strcmp(arg, "--pretty")) {
1953                revs->verbose_header = 1;
1954                revs->pretty_given = 1;
1955                get_commit_format(NULL, revs);
1956        } else if (skip_prefix(arg, "--pretty=", &optarg) ||
1957                   skip_prefix(arg, "--format=", &optarg)) {
1958                /*
1959                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1960                 * not allowed, since the argument is optional.
1961                 */
1962                revs->verbose_header = 1;
1963                revs->pretty_given = 1;
1964                get_commit_format(optarg, revs);
1965        } else if (!strcmp(arg, "--expand-tabs")) {
1966                revs->expand_tabs_in_log = 8;
1967        } else if (!strcmp(arg, "--no-expand-tabs")) {
1968                revs->expand_tabs_in_log = 0;
1969        } else if (skip_prefix(arg, "--expand-tabs=", &arg)) {
1970                int val;
1971                if (strtol_i(arg, 10, &val) < 0 || val < 0)
1972                        die("'%s': not a non-negative integer", arg);
1973                revs->expand_tabs_in_log = val;
1974        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1975                revs->show_notes = 1;
1976                revs->show_notes_given = 1;
1977                revs->notes_opt.use_default_notes = 1;
1978        } else if (!strcmp(arg, "--show-signature")) {
1979                revs->show_signature = 1;
1980        } else if (!strcmp(arg, "--no-show-signature")) {
1981                revs->show_signature = 0;
1982        } else if (!strcmp(arg, "--show-linear-break")) {
1983                revs->break_bar = "                    ..........";
1984                revs->track_linear = 1;
1985                revs->track_first_time = 1;
1986        } else if (skip_prefix(arg, "--show-linear-break=", &optarg)) {
1987                revs->break_bar = xstrdup(optarg);
1988                revs->track_linear = 1;
1989                revs->track_first_time = 1;
1990        } else if (skip_prefix(arg, "--show-notes=", &optarg) ||
1991                   skip_prefix(arg, "--notes=", &optarg)) {
1992                struct strbuf buf = STRBUF_INIT;
1993                revs->show_notes = 1;
1994                revs->show_notes_given = 1;
1995                if (starts_with(arg, "--show-notes=") &&
1996                    revs->notes_opt.use_default_notes < 0)
1997                        revs->notes_opt.use_default_notes = 1;
1998                strbuf_addstr(&buf, optarg);
1999                expand_notes_ref(&buf);
2000                string_list_append(&revs->notes_opt.extra_notes_refs,
2001                                   strbuf_detach(&buf, NULL));
2002        } else if (!strcmp(arg, "--no-notes")) {
2003                revs->show_notes = 0;
2004                revs->show_notes_given = 1;
2005                revs->notes_opt.use_default_notes = -1;
2006                /* we have been strdup'ing ourselves, so trick
2007                 * string_list into free()ing strings */
2008                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
2009                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
2010                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
2011        } else if (!strcmp(arg, "--standard-notes")) {
2012                revs->show_notes_given = 1;
2013                revs->notes_opt.use_default_notes = 1;
2014        } else if (!strcmp(arg, "--no-standard-notes")) {
2015                revs->notes_opt.use_default_notes = 0;
2016        } else if (!strcmp(arg, "--oneline")) {
2017                revs->verbose_header = 1;
2018                get_commit_format("oneline", revs);
2019                revs->pretty_given = 1;
2020                revs->abbrev_commit = 1;
2021        } else if (!strcmp(arg, "--graph")) {
2022                revs->topo_order = 1;
2023                revs->rewrite_parents = 1;
2024                revs->graph = graph_init(revs);
2025        } else if (!strcmp(arg, "--root")) {
2026                revs->show_root_diff = 1;
2027        } else if (!strcmp(arg, "--no-commit-id")) {
2028                revs->no_commit_id = 1;
2029        } else if (!strcmp(arg, "--always")) {
2030                revs->always_show_header = 1;
2031        } else if (!strcmp(arg, "--no-abbrev")) {
2032                revs->abbrev = 0;
2033        } else if (!strcmp(arg, "--abbrev")) {
2034                revs->abbrev = DEFAULT_ABBREV;
2035        } else if (skip_prefix(arg, "--abbrev=", &optarg)) {
2036                revs->abbrev = strtoul(optarg, NULL, 10);
2037                if (revs->abbrev < MINIMUM_ABBREV)
2038                        revs->abbrev = MINIMUM_ABBREV;
2039                else if (revs->abbrev > 40)
2040                        revs->abbrev = 40;
2041        } else if (!strcmp(arg, "--abbrev-commit")) {
2042                revs->abbrev_commit = 1;
2043                revs->abbrev_commit_given = 1;
2044        } else if (!strcmp(arg, "--no-abbrev-commit")) {
2045                revs->abbrev_commit = 0;
2046        } else if (!strcmp(arg, "--full-diff")) {
2047                revs->diff = 1;
2048                revs->full_diff = 1;
2049        } else if (!strcmp(arg, "--full-history")) {
2050                revs->simplify_history = 0;
2051        } else if (!strcmp(arg, "--relative-date")) {
2052                revs->date_mode.type = DATE_RELATIVE;
2053                revs->date_mode_explicit = 1;
2054        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
2055                parse_date_format(optarg, &revs->date_mode);
2056                revs->date_mode_explicit = 1;
2057                return argcount;
2058        } else if (!strcmp(arg, "--log-size")) {
2059                revs->show_log_size = 1;
2060        }
2061        /*
2062         * Grepping the commit log
2063         */
2064        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
2065                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
2066                return argcount;
2067        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
2068                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
2069                return argcount;
2070        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
2071                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
2072                return argcount;
2073        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
2074                add_message_grep(revs, optarg);
2075                return argcount;
2076        } else if (!strcmp(arg, "--grep-debug")) {
2077                revs->grep_filter.debug = 1;
2078        } else if (!strcmp(arg, "--basic-regexp")) {
2079                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_BRE;
2080        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
2081                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_ERE;
2082        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
2083                revs->grep_filter.ignore_case = 1;
2084                DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
2085        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
2086                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
2087        } else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
2088                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
2089        } else if (!strcmp(arg, "--all-match")) {
2090                revs->grep_filter.all_match = 1;
2091        } else if (!strcmp(arg, "--invert-grep")) {
2092                revs->invert_grep = 1;
2093        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
2094                if (strcmp(optarg, "none"))
2095                        git_log_output_encoding = xstrdup(optarg);
2096                else
2097                        git_log_output_encoding = "";
2098                return argcount;
2099        } else if (!strcmp(arg, "--reverse")) {
2100                revs->reverse ^= 1;
2101        } else if (!strcmp(arg, "--children")) {
2102                revs->children.name = "children";
2103                revs->limited = 1;
2104        } else if (!strcmp(arg, "--ignore-missing")) {
2105                revs->ignore_missing = 1;
2106        } else {
2107                int opts = diff_opt_parse(&revs->diffopt, argv, argc, revs->prefix);
2108                if (!opts)
2109                        unkv[(*unkc)++] = arg;
2110                return opts;
2111        }
2112        if (revs->graph && revs->track_linear)
2113                die("--show-linear-break and --graph are incompatible");
2114
2115        return 1;
2116}
2117
2118void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2119                        const struct option *options,
2120                        const char * const usagestr[])
2121{
2122        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2123                                    &ctx->cpidx, ctx->out);
2124        if (n <= 0) {
2125                error("unknown option `%s'", ctx->argv[0]);
2126                usage_with_options(usagestr, options);
2127        }
2128        ctx->argv += n;
2129        ctx->argc -= n;
2130}
2131
2132static int for_each_bisect_ref(struct ref_store *refs, each_ref_fn fn,
2133                               void *cb_data, const char *term)
2134{
2135        struct strbuf bisect_refs = STRBUF_INIT;
2136        int status;
2137        strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
2138        status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data, 0);
2139        strbuf_release(&bisect_refs);
2140        return status;
2141}
2142
2143static int for_each_bad_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2144{
2145        return for_each_bisect_ref(refs, fn, cb_data, term_bad);
2146}
2147
2148static int for_each_good_bisect_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2149{
2150        return for_each_bisect_ref(refs, fn, cb_data, term_good);
2151}
2152
2153static int handle_revision_pseudo_opt(const char *submodule,
2154                                struct rev_info *revs,
2155                                int argc, const char **argv, int *flags)
2156{
2157        const char *arg = argv[0];
2158        const char *optarg;
2159        struct ref_store *refs;
2160        int argcount;
2161
2162        if (submodule) {
2163                /*
2164                 * We need some something like get_submodule_worktrees()
2165                 * before we can go through all worktrees of a submodule,
2166                 * .e.g with adding all HEADs from --all, which is not
2167                 * supported right now, so stick to single worktree.
2168                 */
2169                if (!revs->single_worktree)
2170                        die("BUG: --single-worktree cannot be used together with submodule");
2171                refs = get_submodule_ref_store(submodule);
2172        } else
2173                refs = get_main_ref_store();
2174
2175        /*
2176         * NOTE!
2177         *
2178         * Commands like "git shortlog" will not accept the options below
2179         * unless parse_revision_opt queues them (as opposed to erroring
2180         * out).
2181         *
2182         * When implementing your new pseudo-option, remember to
2183         * register it in the list at the top of handle_revision_opt.
2184         */
2185        if (!strcmp(arg, "--all")) {
2186                handle_refs(refs, revs, *flags, refs_for_each_ref);
2187                handle_refs(refs, revs, *flags, refs_head_ref);
2188                if (!revs->single_worktree) {
2189                        struct all_refs_cb cb;
2190
2191                        init_all_refs_cb(&cb, revs, *flags);
2192                        other_head_refs(handle_one_ref, &cb);
2193                }
2194                clear_ref_exclusion(&revs->ref_excludes);
2195        } else if (!strcmp(arg, "--branches")) {
2196                handle_refs(refs, revs, *flags, refs_for_each_branch_ref);
2197                clear_ref_exclusion(&revs->ref_excludes);
2198        } else if (!strcmp(arg, "--bisect")) {
2199                read_bisect_terms(&term_bad, &term_good);
2200                handle_refs(refs, revs, *flags, for_each_bad_bisect_ref);
2201                handle_refs(refs, revs, *flags ^ (UNINTERESTING | BOTTOM),
2202                            for_each_good_bisect_ref);
2203                revs->bisect = 1;
2204        } else if (!strcmp(arg, "--tags")) {
2205                handle_refs(refs, revs, *flags, refs_for_each_tag_ref);
2206                clear_ref_exclusion(&revs->ref_excludes);
2207        } else if (!strcmp(arg, "--remotes")) {
2208                handle_refs(refs, revs, *flags, refs_for_each_remote_ref);
2209                clear_ref_exclusion(&revs->ref_excludes);
2210        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2211                struct all_refs_cb cb;
2212                init_all_refs_cb(&cb, revs, *flags);
2213                for_each_glob_ref(handle_one_ref, optarg, &cb);
2214                clear_ref_exclusion(&revs->ref_excludes);
2215                return argcount;
2216        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2217                add_ref_exclusion(&revs->ref_excludes, optarg);
2218                return argcount;
2219        } else if (skip_prefix(arg, "--branches=", &optarg)) {
2220                struct all_refs_cb cb;
2221                init_all_refs_cb(&cb, revs, *flags);
2222                for_each_glob_ref_in(handle_one_ref, optarg, "refs/heads/", &cb);
2223                clear_ref_exclusion(&revs->ref_excludes);
2224        } else if (skip_prefix(arg, "--tags=", &optarg)) {
2225                struct all_refs_cb cb;
2226                init_all_refs_cb(&cb, revs, *flags);
2227                for_each_glob_ref_in(handle_one_ref, optarg, "refs/tags/", &cb);
2228                clear_ref_exclusion(&revs->ref_excludes);
2229        } else if (skip_prefix(arg, "--remotes=", &optarg)) {
2230                struct all_refs_cb cb;
2231                init_all_refs_cb(&cb, revs, *flags);
2232                for_each_glob_ref_in(handle_one_ref, optarg, "refs/remotes/", &cb);
2233                clear_ref_exclusion(&revs->ref_excludes);
2234        } else if (!strcmp(arg, "--reflog")) {
2235                add_reflogs_to_pending(revs, *flags);
2236        } else if (!strcmp(arg, "--indexed-objects")) {
2237                add_index_objects_to_pending(revs, *flags);
2238        } else if (!strcmp(arg, "--not")) {
2239                *flags ^= UNINTERESTING | BOTTOM;
2240        } else if (!strcmp(arg, "--no-walk")) {
2241                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2242        } else if (skip_prefix(arg, "--no-walk=", &optarg)) {
2243                /*
2244                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2245                 * not allowed, since the argument is optional.
2246                 */
2247                if (!strcmp(optarg, "sorted"))
2248                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2249                else if (!strcmp(optarg, "unsorted"))
2250                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2251                else
2252                        return error("invalid argument to --no-walk");
2253        } else if (!strcmp(arg, "--do-walk")) {
2254                revs->no_walk = 0;
2255        } else if (!strcmp(arg, "--single-worktree")) {
2256                revs->single_worktree = 1;
2257        } else {
2258                return 0;
2259        }
2260
2261        return 1;
2262}
2263
2264static void NORETURN diagnose_missing_default(const char *def)
2265{
2266        unsigned char sha1[20];
2267        int flags;
2268        const char *refname;
2269
2270        refname = resolve_ref_unsafe(def, 0, sha1, &flags);
2271        if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
2272                die(_("your current branch appears to be broken"));
2273
2274        skip_prefix(refname, "refs/heads/", &refname);
2275        die(_("your current branch '%s' does not have any commits yet"),
2276            refname);
2277}
2278
2279/*
2280 * Parse revision information, filling in the "rev_info" structure,
2281 * and removing the used arguments from the argument list.
2282 *
2283 * Returns the number of arguments left that weren't recognized
2284 * (which are also moved to the head of the argument list)
2285 */
2286int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2287{
2288        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2289        struct cmdline_pathspec prune_data;
2290        const char *submodule = NULL;
2291
2292        memset(&prune_data, 0, sizeof(prune_data));
2293        if (opt)
2294                submodule = opt->submodule;
2295
2296        /* First, search for "--" */
2297        if (opt && opt->assume_dashdash) {
2298                seen_dashdash = 1;
2299        } else {
2300                seen_dashdash = 0;
2301                for (i = 1; i < argc; i++) {
2302                        const char *arg = argv[i];
2303                        if (strcmp(arg, "--"))
2304                                continue;
2305                        argv[i] = NULL;
2306                        argc = i;
2307                        if (argv[i + 1])
2308                                append_prune_data(&prune_data, argv + i + 1);
2309                        seen_dashdash = 1;
2310                        break;
2311                }
2312        }
2313
2314        /* Second, deal with arguments and options */
2315        flags = 0;
2316        revarg_opt = opt ? opt->revarg_opt : 0;
2317        if (seen_dashdash)
2318                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2319        read_from_stdin = 0;
2320        for (left = i = 1; i < argc; i++) {
2321                const char *arg = argv[i];
2322                if (*arg == '-') {
2323                        int opts;
2324
2325                        opts = handle_revision_pseudo_opt(submodule,
2326                                                revs, argc - i, argv + i,
2327                                                &flags);
2328                        if (opts > 0) {
2329                                i += opts - 1;
2330                                continue;
2331                        }
2332
2333                        if (!strcmp(arg, "--stdin")) {
2334                                if (revs->disable_stdin) {
2335                                        argv[left++] = arg;
2336                                        continue;
2337                                }
2338                                if (read_from_stdin++)
2339                                        die("--stdin given twice?");
2340                                read_revisions_from_stdin(revs, &prune_data);
2341                                continue;
2342                        }
2343
2344                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2345                        if (opts > 0) {
2346                                i += opts - 1;
2347                                continue;
2348                        }
2349                        if (opts < 0)
2350                                exit(128);
2351                        continue;
2352                }
2353
2354
2355                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2356                        int j;
2357                        if (seen_dashdash || *arg == '^')
2358                                die("bad revision '%s'", arg);
2359
2360                        /* If we didn't have a "--":
2361                         * (1) all filenames must exist;
2362                         * (2) all rev-args must not be interpretable
2363                         *     as a valid filename.
2364                         * but the latter we have checked in the main loop.
2365                         */
2366                        for (j = i; j < argc; j++)
2367                                verify_filename(revs->prefix, argv[j], j == i);
2368
2369                        append_prune_data(&prune_data, argv + i);
2370                        break;
2371                }
2372                else
2373                        got_rev_arg = 1;
2374        }
2375
2376        if (prune_data.nr) {
2377                /*
2378                 * If we need to introduce the magic "a lone ':' means no
2379                 * pathspec whatsoever", here is the place to do so.
2380                 *
2381                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2382                 *      prune_data.nr = 0;
2383                 *      prune_data.alloc = 0;
2384                 *      free(prune_data.path);
2385                 *      prune_data.path = NULL;
2386                 * } else {
2387                 *      terminate prune_data.alloc with NULL and
2388                 *      call init_pathspec() to set revs->prune_data here.
2389                 * }
2390                 */
2391                ALLOC_GROW(prune_data.path, prune_data.nr + 1, prune_data.alloc);
2392                prune_data.path[prune_data.nr++] = NULL;
2393                parse_pathspec(&revs->prune_data, 0, 0,
2394                               revs->prefix, prune_data.path);
2395        }
2396
2397        if (revs->def == NULL)
2398                revs->def = opt ? opt->def : NULL;
2399        if (opt && opt->tweak)
2400                opt->tweak(revs, opt);
2401        if (revs->show_merge)
2402                prepare_show_merge(revs);
2403        if (revs->def && !revs->pending.nr && !revs->rev_input_given && !got_rev_arg) {
2404                struct object_id oid;
2405                struct object *object;
2406                struct object_context oc;
2407                if (get_oid_with_context(revs->def, 0, &oid, &oc))
2408                        diagnose_missing_default(revs->def);
2409                object = get_reference(revs, revs->def, &oid, 0);
2410                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2411        }
2412
2413        /* Did the user ask for any diff output? Run the diff! */
2414        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2415                revs->diff = 1;
2416
2417        /* Pickaxe, diff-filter and rename following need diffs */
2418        if (revs->diffopt.pickaxe ||
2419            revs->diffopt.filter ||
2420            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2421                revs->diff = 1;
2422
2423        if (revs->topo_order)
2424                revs->limited = 1;
2425
2426        if (revs->prune_data.nr) {
2427                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2428                /* Can't prune commits with rename following: the paths change.. */
2429                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2430                        revs->prune = 1;
2431                if (!revs->full_diff)
2432                        copy_pathspec(&revs->diffopt.pathspec,
2433                                      &revs->prune_data);
2434        }
2435        if (revs->combine_merges)
2436                revs->ignore_merges = 0;
2437        revs->diffopt.abbrev = revs->abbrev;
2438
2439        if (revs->line_level_traverse) {
2440                revs->limited = 1;
2441                revs->topo_order = 1;
2442        }
2443
2444        diff_setup_done(&revs->diffopt);
2445
2446        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2447                                 &revs->grep_filter);
2448        compile_grep_patterns(&revs->grep_filter);
2449
2450        if (revs->reverse && revs->reflog_info)
2451                die("cannot combine --reverse with --walk-reflogs");
2452        if (revs->reflog_info && revs->limited)
2453                die("cannot combine --walk-reflogs with history-limiting options");
2454        if (revs->rewrite_parents && revs->children.name)
2455                die("cannot combine --parents and --children");
2456
2457        /*
2458         * Limitations on the graph functionality
2459         */
2460        if (revs->reverse && revs->graph)
2461                die("cannot combine --reverse with --graph");
2462
2463        if (revs->reflog_info && revs->graph)
2464                die("cannot combine --walk-reflogs with --graph");
2465        if (revs->no_walk && revs->graph)
2466                die("cannot combine --no-walk with --graph");
2467        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2468                die("cannot use --grep-reflog without --walk-reflogs");
2469
2470        if (revs->first_parent_only && revs->bisect)
2471                die(_("--first-parent is incompatible with --bisect"));
2472
2473        if (revs->expand_tabs_in_log < 0)
2474                revs->expand_tabs_in_log = revs->expand_tabs_in_log_default;
2475
2476        return left;
2477}
2478
2479static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2480{
2481        struct commit_list *l = xcalloc(1, sizeof(*l));
2482
2483        l->item = child;
2484        l->next = add_decoration(&revs->children, &parent->object, l);
2485}
2486
2487static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2488{
2489        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2490        struct commit_list **pp, *p;
2491        int surviving_parents;
2492
2493        /* Examine existing parents while marking ones we have seen... */
2494        pp = &commit->parents;
2495        surviving_parents = 0;
2496        while ((p = *pp) != NULL) {
2497                struct commit *parent = p->item;
2498                if (parent->object.flags & TMP_MARK) {
2499                        *pp = p->next;
2500                        if (ts)
2501                                compact_treesame(revs, commit, surviving_parents);
2502                        continue;
2503                }
2504                parent->object.flags |= TMP_MARK;
2505                surviving_parents++;
2506                pp = &p->next;
2507        }
2508        /* clear the temporary mark */
2509        for (p = commit->parents; p; p = p->next) {
2510                p->item->object.flags &= ~TMP_MARK;
2511        }
2512        /* no update_treesame() - removing duplicates can't affect TREESAME */
2513        return surviving_parents;
2514}
2515
2516struct merge_simplify_state {
2517        struct commit *simplified;
2518};
2519
2520static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2521{
2522        struct merge_simplify_state *st;
2523
2524        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2525        if (!st) {
2526                st = xcalloc(1, sizeof(*st));
2527                add_decoration(&revs->merge_simplification, &commit->object, st);
2528        }
2529        return st;
2530}
2531
2532static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2533{
2534        struct commit_list *h = reduce_heads(commit->parents);
2535        int i = 0, marked = 0;
2536        struct commit_list *po, *pn;
2537
2538        /* Want these for sanity-checking only */
2539        int orig_cnt = commit_list_count(commit->parents);
2540        int cnt = commit_list_count(h);
2541
2542        /*
2543         * Not ready to remove items yet, just mark them for now, based
2544         * on the output of reduce_heads(). reduce_heads outputs the reduced
2545         * set in its original order, so this isn't too hard.
2546         */
2547        po = commit->parents;
2548        pn = h;
2549        while (po) {
2550                if (pn && po->item == pn->item) {
2551                        pn = pn->next;
2552                        i++;
2553                } else {
2554                        po->item->object.flags |= TMP_MARK;
2555                        marked++;
2556                }
2557                po=po->next;
2558        }
2559
2560        if (i != cnt || cnt+marked != orig_cnt)
2561                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2562
2563        free_commit_list(h);
2564
2565        return marked;
2566}
2567
2568static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2569{
2570        struct commit_list *p;
2571        int marked = 0;
2572
2573        for (p = commit->parents; p; p = p->next) {
2574                struct commit *parent = p->item;
2575                if (!parent->parents && (parent->object.flags & TREESAME)) {
2576                        parent->object.flags |= TMP_MARK;
2577                        marked++;
2578                }
2579        }
2580
2581        return marked;
2582}
2583
2584/*
2585 * Awkward naming - this means one parent we are TREESAME to.
2586 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2587 * empty tree). Better name suggestions?
2588 */
2589static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2590{
2591        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2592        struct commit *unmarked = NULL, *marked = NULL;
2593        struct commit_list *p;
2594        unsigned n;
2595
2596        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2597                if (ts->treesame[n]) {
2598                        if (p->item->object.flags & TMP_MARK) {
2599                                if (!marked)
2600                                        marked = p->item;
2601                        } else {
2602                                if (!unmarked) {
2603                                        unmarked = p->item;
2604                                        break;
2605                                }
2606                        }
2607                }
2608        }
2609
2610        /*
2611         * If we are TREESAME to a marked-for-deletion parent, but not to any
2612         * unmarked parents, unmark the first TREESAME parent. This is the
2613         * parent that the default simplify_history==1 scan would have followed,
2614         * and it doesn't make sense to omit that path when asking for a
2615         * simplified full history. Retaining it improves the chances of
2616         * understanding odd missed merges that took an old version of a file.
2617         *
2618         * Example:
2619         *
2620         *   I--------*X       A modified the file, but mainline merge X used
2621         *    \       /        "-s ours", so took the version from I. X is
2622         *     `-*A--'         TREESAME to I and !TREESAME to A.
2623         *
2624         * Default log from X would produce "I". Without this check,
2625         * --full-history --simplify-merges would produce "I-A-X", showing
2626         * the merge commit X and that it changed A, but not making clear that
2627         * it had just taken the I version. With this check, the topology above
2628         * is retained.
2629         *
2630         * Note that it is possible that the simplification chooses a different
2631         * TREESAME parent from the default, in which case this test doesn't
2632         * activate, and we _do_ drop the default parent. Example:
2633         *
2634         *   I------X         A modified the file, but it was reverted in B,
2635         *    \    /          meaning mainline merge X is TREESAME to both
2636         *    *A-*B           parents.
2637         *
2638         * Default log would produce "I" by following the first parent;
2639         * --full-history --simplify-merges will produce "I-A-B". But this is a
2640         * reasonable result - it presents a logical full history leading from
2641         * I to X, and X is not an important merge.
2642         */
2643        if (!unmarked && marked) {
2644                marked->object.flags &= ~TMP_MARK;
2645                return 1;
2646        }
2647
2648        return 0;
2649}
2650
2651static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2652{
2653        struct commit_list **pp, *p;
2654        int nth_parent, removed = 0;
2655
2656        pp = &commit->parents;
2657        nth_parent = 0;
2658        while ((p = *pp) != NULL) {
2659                struct commit *parent = p->item;
2660                if (parent->object.flags & TMP_MARK) {
2661                        parent->object.flags &= ~TMP_MARK;
2662                        *pp = p->next;
2663                        free(p);
2664                        removed++;
2665                        compact_treesame(revs, commit, nth_parent);
2666                        continue;
2667                }
2668                pp = &p->next;
2669                nth_parent++;
2670        }
2671
2672        /* Removing parents can only increase TREESAMEness */
2673        if (removed && !(commit->object.flags & TREESAME))
2674                update_treesame(revs, commit);
2675
2676        return nth_parent;
2677}
2678
2679static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2680{
2681        struct commit_list *p;
2682        struct commit *parent;
2683        struct merge_simplify_state *st, *pst;
2684        int cnt;
2685
2686        st = locate_simplify_state(revs, commit);
2687
2688        /*
2689         * Have we handled this one?
2690         */
2691        if (st->simplified)
2692                return tail;
2693
2694        /*
2695         * An UNINTERESTING commit simplifies to itself, so does a
2696         * root commit.  We do not rewrite parents of such commit
2697         * anyway.
2698         */
2699        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2700                st->simplified = commit;
2701                return tail;
2702        }
2703
2704        /*
2705         * Do we know what commit all of our parents that matter
2706         * should be rewritten to?  Otherwise we are not ready to
2707         * rewrite this one yet.
2708         */
2709        for (cnt = 0, p = commit->parents; p; p = p->next) {
2710                pst = locate_simplify_state(revs, p->item);
2711                if (!pst->simplified) {
2712                        tail = &commit_list_insert(p->item, tail)->next;
2713                        cnt++;
2714                }
2715                if (revs->first_parent_only)
2716                        break;
2717        }
2718        if (cnt) {
2719                tail = &commit_list_insert(commit, tail)->next;
2720                return tail;
2721        }
2722
2723        /*
2724         * Rewrite our list of parents. Note that this cannot
2725         * affect our TREESAME flags in any way - a commit is
2726         * always TREESAME to its simplification.
2727         */
2728        for (p = commit->parents; p; p = p->next) {
2729                pst = locate_simplify_state(revs, p->item);
2730                p->item = pst->simplified;
2731                if (revs->first_parent_only)
2732                        break;
2733        }
2734
2735        if (revs->first_parent_only)
2736                cnt = 1;
2737        else
2738                cnt = remove_duplicate_parents(revs, commit);
2739
2740        /*
2741         * It is possible that we are a merge and one side branch
2742         * does not have any commit that touches the given paths;
2743         * in such a case, the immediate parent from that branch
2744         * will be rewritten to be the merge base.
2745         *
2746         *      o----X          X: the commit we are looking at;
2747         *     /    /           o: a commit that touches the paths;
2748         * ---o----'
2749         *
2750         * Further, a merge of an independent branch that doesn't
2751         * touch the path will reduce to a treesame root parent:
2752         *
2753         *  ----o----X          X: the commit we are looking at;
2754         *          /           o: a commit that touches the paths;
2755         *         r            r: a root commit not touching the paths
2756         *
2757         * Detect and simplify both cases.
2758         */
2759        if (1 < cnt) {
2760                int marked = mark_redundant_parents(revs, commit);
2761                marked += mark_treesame_root_parents(revs, commit);
2762                if (marked)
2763                        marked -= leave_one_treesame_to_parent(revs, commit);
2764                if (marked)
2765                        cnt = remove_marked_parents(revs, commit);
2766        }
2767
2768        /*
2769         * A commit simplifies to itself if it is a root, if it is
2770         * UNINTERESTING, if it touches the given paths, or if it is a
2771         * merge and its parents don't simplify to one relevant commit
2772         * (the first two cases are already handled at the beginning of
2773         * this function).
2774         *
2775         * Otherwise, it simplifies to what its sole relevant parent
2776         * simplifies to.
2777         */
2778        if (!cnt ||
2779            (commit->object.flags & UNINTERESTING) ||
2780            !(commit->object.flags & TREESAME) ||
2781            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2782                st->simplified = commit;
2783        else {
2784                pst = locate_simplify_state(revs, parent);
2785                st->simplified = pst->simplified;
2786        }
2787        return tail;
2788}
2789
2790static void simplify_merges(struct rev_info *revs)
2791{
2792        struct commit_list *list, *next;
2793        struct commit_list *yet_to_do, **tail;
2794        struct commit *commit;
2795
2796        if (!revs->prune)
2797                return;
2798
2799        /* feed the list reversed */
2800        yet_to_do = NULL;
2801        for (list = revs->commits; list; list = next) {
2802                commit = list->item;
2803                next = list->next;
2804                /*
2805                 * Do not free(list) here yet; the original list
2806                 * is used later in this function.
2807                 */
2808                commit_list_insert(commit, &yet_to_do);
2809        }
2810        while (yet_to_do) {
2811                list = yet_to_do;
2812                yet_to_do = NULL;
2813                tail = &yet_to_do;
2814                while (list) {
2815                        commit = pop_commit(&list);
2816                        tail = simplify_one(revs, commit, tail);
2817                }
2818        }
2819
2820        /* clean up the result, removing the simplified ones */
2821        list = revs->commits;
2822        revs->commits = NULL;
2823        tail = &revs->commits;
2824        while (list) {
2825                struct merge_simplify_state *st;
2826
2827                commit = pop_commit(&list);
2828                st = locate_simplify_state(revs, commit);
2829                if (st->simplified == commit)
2830                        tail = &commit_list_insert(commit, tail)->next;
2831        }
2832}
2833
2834static void set_children(struct rev_info *revs)
2835{
2836        struct commit_list *l;
2837        for (l = revs->commits; l; l = l->next) {
2838                struct commit *commit = l->item;
2839                struct commit_list *p;
2840
2841                for (p = commit->parents; p; p = p->next)
2842                        add_child(revs, p->item, commit);
2843        }
2844}
2845
2846void reset_revision_walk(void)
2847{
2848        clear_object_flags(SEEN | ADDED | SHOWN);
2849}
2850
2851int prepare_revision_walk(struct rev_info *revs)
2852{
2853        int i;
2854        struct object_array old_pending;
2855        struct commit_list **next = &revs->commits;
2856
2857        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2858        revs->pending.nr = 0;
2859        revs->pending.alloc = 0;
2860        revs->pending.objects = NULL;
2861        for (i = 0; i < old_pending.nr; i++) {
2862                struct object_array_entry *e = old_pending.objects + i;
2863                struct commit *commit = handle_commit(revs, e);
2864                if (commit) {
2865                        if (!(commit->object.flags & SEEN)) {
2866                                commit->object.flags |= SEEN;
2867                                next = commit_list_append(commit, next);
2868                        }
2869                }
2870        }
2871        if (!revs->leak_pending)
2872                object_array_clear(&old_pending);
2873
2874        /* Signal whether we need per-parent treesame decoration */
2875        if (revs->simplify_merges ||
2876            (revs->limited && limiting_can_increase_treesame(revs)))
2877                revs->treesame.name = "treesame";
2878
2879        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2880                commit_list_sort_by_date(&revs->commits);
2881        if (revs->no_walk)
2882                return 0;
2883        if (revs->limited)
2884                if (limit_list(revs) < 0)
2885                        return -1;
2886        if (revs->topo_order)
2887                sort_in_topological_order(&revs->commits, revs->sort_order);
2888        if (revs->line_level_traverse)
2889                line_log_filter(revs);
2890        if (revs->simplify_merges)
2891                simplify_merges(revs);
2892        if (revs->children.name)
2893                set_children(revs);
2894        return 0;
2895}
2896
2897static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2898{
2899        struct commit_list *cache = NULL;
2900
2901        for (;;) {
2902                struct commit *p = *pp;
2903                if (!revs->limited)
2904                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2905                                return rewrite_one_error;
2906                if (p->object.flags & UNINTERESTING)
2907                        return rewrite_one_ok;
2908                if (!(p->object.flags & TREESAME))
2909                        return rewrite_one_ok;
2910                if (!p->parents)
2911                        return rewrite_one_noparents;
2912                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2913                        return rewrite_one_ok;
2914                *pp = p;
2915        }
2916}
2917
2918int rewrite_parents(struct rev_info *revs, struct commit *commit,
2919        rewrite_parent_fn_t rewrite_parent)
2920{
2921        struct commit_list **pp = &commit->parents;
2922        while (*pp) {
2923                struct commit_list *parent = *pp;
2924                switch (rewrite_parent(revs, &parent->item)) {
2925                case rewrite_one_ok:
2926                        break;
2927                case rewrite_one_noparents:
2928                        *pp = parent->next;
2929                        continue;
2930                case rewrite_one_error:
2931                        return -1;
2932                }
2933                pp = &parent->next;
2934        }
2935        remove_duplicate_parents(revs, commit);
2936        return 0;
2937}
2938
2939static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2940{
2941        char *person, *endp;
2942        size_t len, namelen, maillen;
2943        const char *name;
2944        const char *mail;
2945        struct ident_split ident;
2946
2947        person = strstr(buf->buf, what);
2948        if (!person)
2949                return 0;
2950
2951        person += strlen(what);
2952        endp = strchr(person, '\n');
2953        if (!endp)
2954                return 0;
2955
2956        len = endp - person;
2957
2958        if (split_ident_line(&ident, person, len))
2959                return 0;
2960
2961        mail = ident.mail_begin;
2962        maillen = ident.mail_end - ident.mail_begin;
2963        name = ident.name_begin;
2964        namelen = ident.name_end - ident.name_begin;
2965
2966        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2967                struct strbuf namemail = STRBUF_INIT;
2968
2969                strbuf_addf(&namemail, "%.*s <%.*s>",
2970                            (int)namelen, name, (int)maillen, mail);
2971
2972                strbuf_splice(buf, ident.name_begin - buf->buf,
2973                              ident.mail_end - ident.name_begin + 1,
2974                              namemail.buf, namemail.len);
2975
2976                strbuf_release(&namemail);
2977
2978                return 1;
2979        }
2980
2981        return 0;
2982}
2983
2984static int commit_match(struct commit *commit, struct rev_info *opt)
2985{
2986        int retval;
2987        const char *encoding;
2988        const char *message;
2989        struct strbuf buf = STRBUF_INIT;
2990
2991        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2992                return 1;
2993
2994        /* Prepend "fake" headers as needed */
2995        if (opt->grep_filter.use_reflog_filter) {
2996                strbuf_addstr(&buf, "reflog ");
2997                get_reflog_message(&buf, opt->reflog_info);
2998                strbuf_addch(&buf, '\n');
2999        }
3000
3001        /*
3002         * We grep in the user's output encoding, under the assumption that it
3003         * is the encoding they are most likely to write their grep pattern
3004         * for. In addition, it means we will match the "notes" encoding below,
3005         * so we will not end up with a buffer that has two different encodings
3006         * in it.
3007         */
3008        encoding = get_log_output_encoding();
3009        message = logmsg_reencode(commit, NULL, encoding);
3010
3011        /* Copy the commit to temporary if we are using "fake" headers */
3012        if (buf.len)
3013                strbuf_addstr(&buf, message);
3014
3015        if (opt->grep_filter.header_list && opt->mailmap) {
3016                if (!buf.len)
3017                        strbuf_addstr(&buf, message);
3018
3019                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
3020                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
3021        }
3022
3023        /* Append "fake" message parts as needed */
3024        if (opt->show_notes) {
3025                if (!buf.len)
3026                        strbuf_addstr(&buf, message);
3027                format_display_notes(&commit->object.oid, &buf, encoding, 1);
3028        }
3029
3030        /*
3031         * Find either in the original commit message, or in the temporary.
3032         * Note that we cast away the constness of "message" here. It is
3033         * const because it may come from the cached commit buffer. That's OK,
3034         * because we know that it is modifiable heap memory, and that while
3035         * grep_buffer may modify it for speed, it will restore any
3036         * changes before returning.
3037         */
3038        if (buf.len)
3039                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
3040        else
3041                retval = grep_buffer(&opt->grep_filter,
3042                                     (char *)message, strlen(message));
3043        strbuf_release(&buf);
3044        unuse_commit_buffer(commit, message);
3045        return opt->invert_grep ? !retval : retval;
3046}
3047
3048static inline int want_ancestry(const struct rev_info *revs)
3049{
3050        return (revs->rewrite_parents || revs->children.name);
3051}
3052
3053/*
3054 * Return a timestamp to be used for --since/--until comparisons for this
3055 * commit, based on the revision options.
3056 */
3057static timestamp_t comparison_date(const struct rev_info *revs,
3058                                   struct commit *commit)
3059{
3060        return revs->reflog_info ?
3061                get_reflog_timestamp(revs->reflog_info) :
3062                commit->date;
3063}
3064
3065enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
3066{
3067        if (commit->object.flags & SHOWN)
3068                return commit_ignore;
3069        if (revs->unpacked && has_sha1_pack(commit->object.oid.hash))
3070                return commit_ignore;
3071        if (revs->show_all)
3072                return commit_show;
3073        if (commit->object.flags & UNINTERESTING)
3074                return commit_ignore;
3075        if (revs->min_age != -1 &&
3076            comparison_date(revs, commit) > revs->min_age)
3077                        return commit_ignore;
3078        if (revs->min_parents || (revs->max_parents >= 0)) {
3079                int n = commit_list_count(commit->parents);
3080                if ((n < revs->min_parents) ||
3081                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
3082                        return commit_ignore;
3083        }
3084        if (!commit_match(commit, revs))
3085                return commit_ignore;
3086        if (revs->prune && revs->dense) {
3087                /* Commit without changes? */
3088                if (commit->object.flags & TREESAME) {
3089                        int n;
3090                        struct commit_list *p;
3091                        /* drop merges unless we want parenthood */
3092                        if (!want_ancestry(revs))
3093                                return commit_ignore;
3094                        /*
3095                         * If we want ancestry, then need to keep any merges
3096                         * between relevant commits to tie together topology.
3097                         * For consistency with TREESAME and simplification
3098                         * use "relevant" here rather than just INTERESTING,
3099                         * to treat bottom commit(s) as part of the topology.
3100                         */
3101                        for (n = 0, p = commit->parents; p; p = p->next)
3102                                if (relevant_commit(p->item))
3103                                        if (++n >= 2)
3104                                                return commit_show;
3105                        return commit_ignore;
3106                }
3107        }
3108        return commit_show;
3109}
3110
3111define_commit_slab(saved_parents, struct commit_list *);
3112
3113#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
3114
3115/*
3116 * You may only call save_parents() once per commit (this is checked
3117 * for non-root commits).
3118 */
3119static void save_parents(struct rev_info *revs, struct commit *commit)
3120{
3121        struct commit_list **pp;
3122
3123        if (!revs->saved_parents_slab) {
3124                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
3125                init_saved_parents(revs->saved_parents_slab);
3126        }
3127
3128        pp = saved_parents_at(revs->saved_parents_slab, commit);
3129
3130        /*
3131         * When walking with reflogs, we may visit the same commit
3132         * several times: once for each appearance in the reflog.
3133         *
3134         * In this case, save_parents() will be called multiple times.
3135         * We want to keep only the first set of parents.  We need to
3136         * store a sentinel value for an empty (i.e., NULL) parent
3137         * list to distinguish it from a not-yet-saved list, however.
3138         */
3139        if (*pp)
3140                return;
3141        if (commit->parents)
3142                *pp = copy_commit_list(commit->parents);
3143        else
3144                *pp = EMPTY_PARENT_LIST;
3145}
3146
3147static void free_saved_parents(struct rev_info *revs)
3148{
3149        if (revs->saved_parents_slab)
3150                clear_saved_parents(revs->saved_parents_slab);
3151}
3152
3153struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
3154{
3155        struct commit_list *parents;
3156
3157        if (!revs->saved_parents_slab)
3158                return commit->parents;
3159
3160        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3161        if (parents == EMPTY_PARENT_LIST)
3162                return NULL;
3163        return parents;
3164}
3165
3166enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
3167{
3168        enum commit_action action = get_commit_action(revs, commit);
3169
3170        if (action == commit_show &&
3171            !revs->show_all &&
3172            revs->prune && revs->dense && want_ancestry(revs)) {
3173                /*
3174                 * --full-diff on simplified parents is no good: it
3175                 * will show spurious changes from the commits that
3176                 * were elided.  So we save the parents on the side
3177                 * when --full-diff is in effect.
3178                 */
3179                if (revs->full_diff)
3180                        save_parents(revs, commit);
3181                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3182                        return commit_error;
3183        }
3184        return action;
3185}
3186
3187static void track_linear(struct rev_info *revs, struct commit *commit)
3188{
3189        if (revs->track_first_time) {
3190                revs->linear = 1;
3191                revs->track_first_time = 0;
3192        } else {
3193                struct commit_list *p;
3194                for (p = revs->previous_parents; p; p = p->next)
3195                        if (p->item == NULL || /* first commit */
3196                            !oidcmp(&p->item->object.oid, &commit->object.oid))
3197                                break;
3198                revs->linear = p != NULL;
3199        }
3200        if (revs->reverse) {
3201                if (revs->linear)
3202                        commit->object.flags |= TRACK_LINEAR;
3203        }
3204        free_commit_list(revs->previous_parents);
3205        revs->previous_parents = copy_commit_list(commit->parents);
3206}
3207
3208static struct commit *get_revision_1(struct rev_info *revs)
3209{
3210        while (1) {
3211                struct commit *commit;
3212
3213                if (revs->reflog_info)
3214                        commit = next_reflog_entry(revs->reflog_info);
3215                else
3216                        commit = pop_commit(&revs->commits);
3217
3218                if (!commit)
3219                        return NULL;
3220
3221                if (revs->reflog_info)
3222                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3223
3224                /*
3225                 * If we haven't done the list limiting, we need to look at
3226                 * the parents here. We also need to do the date-based limiting
3227                 * that we'd otherwise have done in limit_list().
3228                 */
3229                if (!revs->limited) {
3230                        if (revs->max_age != -1 &&
3231                            comparison_date(revs, commit) < revs->max_age)
3232                                continue;
3233
3234                        if (revs->reflog_info)
3235                                try_to_simplify_commit(revs, commit);
3236                        else if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3237                                if (!revs->ignore_missing_links)
3238                                        die("Failed to traverse parents of commit %s",
3239                                                oid_to_hex(&commit->object.oid));
3240                        }
3241                }
3242
3243                switch (simplify_commit(revs, commit)) {
3244                case commit_ignore:
3245                        continue;
3246                case commit_error:
3247                        die("Failed to simplify parents of commit %s",
3248                            oid_to_hex(&commit->object.oid));
3249                default:
3250                        if (revs->track_linear)
3251                                track_linear(revs, commit);
3252                        return commit;
3253                }
3254        }
3255}
3256
3257/*
3258 * Return true for entries that have not yet been shown.  (This is an
3259 * object_array_each_func_t.)
3260 */
3261static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3262{
3263        return !(entry->item->flags & SHOWN);
3264}
3265
3266/*
3267 * If array is on the verge of a realloc, garbage-collect any entries
3268 * that have already been shown to try to free up some space.
3269 */
3270static void gc_boundary(struct object_array *array)
3271{
3272        if (array->nr == array->alloc)
3273                object_array_filter(array, entry_unshown, NULL);
3274}
3275
3276static void create_boundary_commit_list(struct rev_info *revs)
3277{
3278        unsigned i;
3279        struct commit *c;
3280        struct object_array *array = &revs->boundary_commits;
3281        struct object_array_entry *objects = array->objects;
3282
3283        /*
3284         * If revs->commits is non-NULL at this point, an error occurred in
3285         * get_revision_1().  Ignore the error and continue printing the
3286         * boundary commits anyway.  (This is what the code has always
3287         * done.)
3288         */
3289        if (revs->commits) {
3290                free_commit_list(revs->commits);
3291                revs->commits = NULL;
3292        }
3293
3294        /*
3295         * Put all of the actual boundary commits from revs->boundary_commits
3296         * into revs->commits
3297         */
3298        for (i = 0; i < array->nr; i++) {
3299                c = (struct commit *)(objects[i].item);
3300                if (!c)
3301                        continue;
3302                if (!(c->object.flags & CHILD_SHOWN))
3303                        continue;
3304                if (c->object.flags & (SHOWN | BOUNDARY))
3305                        continue;
3306                c->object.flags |= BOUNDARY;
3307                commit_list_insert(c, &revs->commits);
3308        }
3309
3310        /*
3311         * If revs->topo_order is set, sort the boundary commits
3312         * in topological order
3313         */
3314        sort_in_topological_order(&revs->commits, revs->sort_order);
3315}
3316
3317static struct commit *get_revision_internal(struct rev_info *revs)
3318{
3319        struct commit *c = NULL;
3320        struct commit_list *l;
3321
3322        if (revs->boundary == 2) {
3323                /*
3324                 * All of the normal commits have already been returned,
3325                 * and we are now returning boundary commits.
3326                 * create_boundary_commit_list() has populated
3327                 * revs->commits with the remaining commits to return.
3328                 */
3329                c = pop_commit(&revs->commits);
3330                if (c)
3331                        c->object.flags |= SHOWN;
3332                return c;
3333        }
3334
3335        /*
3336         * If our max_count counter has reached zero, then we are done. We
3337         * don't simply return NULL because we still might need to show
3338         * boundary commits. But we want to avoid calling get_revision_1, which
3339         * might do a considerable amount of work finding the next commit only
3340         * for us to throw it away.
3341         *
3342         * If it is non-zero, then either we don't have a max_count at all
3343         * (-1), or it is still counting, in which case we decrement.
3344         */
3345        if (revs->max_count) {
3346                c = get_revision_1(revs);
3347                if (c) {
3348                        while (revs->skip_count > 0) {
3349                                revs->skip_count--;
3350                                c = get_revision_1(revs);
3351                                if (!c)
3352                                        break;
3353                        }
3354                }
3355
3356                if (revs->max_count > 0)
3357                        revs->max_count--;
3358        }
3359
3360        if (c)
3361                c->object.flags |= SHOWN;
3362
3363        if (!revs->boundary)
3364                return c;
3365
3366        if (!c) {
3367                /*
3368                 * get_revision_1() runs out the commits, and
3369                 * we are done computing the boundaries.
3370                 * switch to boundary commits output mode.
3371                 */
3372                revs->boundary = 2;
3373
3374                /*
3375                 * Update revs->commits to contain the list of
3376                 * boundary commits.
3377                 */
3378                create_boundary_commit_list(revs);
3379
3380                return get_revision_internal(revs);
3381        }
3382
3383        /*
3384         * boundary commits are the commits that are parents of the
3385         * ones we got from get_revision_1() but they themselves are
3386         * not returned from get_revision_1().  Before returning
3387         * 'c', we need to mark its parents that they could be boundaries.
3388         */
3389
3390        for (l = c->parents; l; l = l->next) {
3391                struct object *p;
3392                p = &(l->item->object);
3393                if (p->flags & (CHILD_SHOWN | SHOWN))
3394                        continue;
3395                p->flags |= CHILD_SHOWN;
3396                gc_boundary(&revs->boundary_commits);
3397                add_object_array(p, NULL, &revs->boundary_commits);
3398        }
3399
3400        return c;
3401}
3402
3403struct commit *get_revision(struct rev_info *revs)
3404{
3405        struct commit *c;
3406        struct commit_list *reversed;
3407
3408        if (revs->reverse) {
3409                reversed = NULL;
3410                while ((c = get_revision_internal(revs)))
3411                        commit_list_insert(c, &reversed);
3412                revs->commits = reversed;
3413                revs->reverse = 0;
3414                revs->reverse_output_stage = 1;
3415        }
3416
3417        if (revs->reverse_output_stage) {
3418                c = pop_commit(&revs->commits);
3419                if (revs->track_linear)
3420                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3421                return c;
3422        }
3423
3424        c = get_revision_internal(revs);
3425        if (c && revs->graph)
3426                graph_update(revs->graph, c);
3427        if (!c) {
3428                free_saved_parents(revs);
3429                if (revs->previous_parents) {
3430                        free_commit_list(revs->previous_parents);
3431                        revs->previous_parents = NULL;
3432                }
3433        }
3434        return c;
3435}
3436
3437char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3438{
3439        if (commit->object.flags & BOUNDARY)
3440                return "-";
3441        else if (commit->object.flags & UNINTERESTING)
3442                return "^";
3443        else if (commit->object.flags & PATCHSAME)
3444                return "=";
3445        else if (!revs || revs->left_right) {
3446                if (commit->object.flags & SYMMETRIC_LEFT)
3447                        return "<";
3448                else
3449                        return ">";
3450        } else if (revs->graph)
3451                return "*";
3452        else if (revs->cherry_mark)
3453                return "+";
3454        return "";
3455}
3456
3457void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3458{
3459        char *mark = get_revision_mark(revs, commit);
3460        if (!strlen(mark))
3461                return;
3462        fputs(mark, stdout);
3463        putchar(' ');
3464}