revision.con commit Merge branch 'vr/merge-base-doc' into maint (8de4338)
   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
  17volatile show_early_output_fn_t show_early_output;
  18
  19char *path_name(const struct name_path *path, const char *name)
  20{
  21        const struct name_path *p;
  22        char *n, *m;
  23        int nlen = strlen(name);
  24        int len = nlen + 1;
  25
  26        for (p = path; p; p = p->up) {
  27                if (p->elem_len)
  28                        len += p->elem_len + 1;
  29        }
  30        n = xmalloc(len);
  31        m = n + len - (nlen + 1);
  32        strcpy(m, name);
  33        for (p = path; p; p = p->up) {
  34                if (p->elem_len) {
  35                        m -= p->elem_len + 1;
  36                        memcpy(m, p->elem, p->elem_len);
  37                        m[p->elem_len] = '/';
  38                }
  39        }
  40        return n;
  41}
  42
  43void add_object(struct object *obj,
  44                struct object_array *p,
  45                struct name_path *path,
  46                const char *name)
  47{
  48        add_object_array(obj, path_name(path, name), p);
  49}
  50
  51static void mark_blob_uninteresting(struct blob *blob)
  52{
  53        if (!blob)
  54                return;
  55        if (blob->object.flags & UNINTERESTING)
  56                return;
  57        blob->object.flags |= UNINTERESTING;
  58}
  59
  60void mark_tree_uninteresting(struct tree *tree)
  61{
  62        struct tree_desc desc;
  63        struct name_entry entry;
  64        struct object *obj = &tree->object;
  65
  66        if (!tree)
  67                return;
  68        if (obj->flags & UNINTERESTING)
  69                return;
  70        obj->flags |= UNINTERESTING;
  71        if (!has_sha1_file(obj->sha1))
  72                return;
  73        if (parse_tree(tree) < 0)
  74                die("bad tree %s", sha1_to_hex(obj->sha1));
  75
  76        init_tree_desc(&desc, tree->buffer, tree->size);
  77        while (tree_entry(&desc, &entry)) {
  78                switch (object_type(entry.mode)) {
  79                case OBJ_TREE:
  80                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  81                        break;
  82                case OBJ_BLOB:
  83                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  84                        break;
  85                default:
  86                        /* Subproject commit - not in this repository */
  87                        break;
  88                }
  89        }
  90
  91        /*
  92         * We don't care about the tree any more
  93         * after it has been marked uninteresting.
  94         */
  95        free(tree->buffer);
  96        tree->buffer = NULL;
  97}
  98
  99void mark_parents_uninteresting(struct commit *commit)
 100{
 101        struct commit_list *parents = commit->parents;
 102
 103        while (parents) {
 104                struct commit *commit = parents->item;
 105                if (!(commit->object.flags & UNINTERESTING)) {
 106                        commit->object.flags |= UNINTERESTING;
 107
 108                        /*
 109                         * Normally we haven't parsed the parent
 110                         * yet, so we won't have a parent of a parent
 111                         * here. However, it may turn out that we've
 112                         * reached this commit some other way (where it
 113                         * wasn't uninteresting), in which case we need
 114                         * to mark its parents recursively too..
 115                         */
 116                        if (commit->parents)
 117                                mark_parents_uninteresting(commit);
 118                }
 119
 120                /*
 121                 * A missing commit is ok iff its parent is marked
 122                 * uninteresting.
 123                 *
 124                 * We just mark such a thing parsed, so that when
 125                 * it is popped next time around, we won't be trying
 126                 * to parse it and get an error.
 127                 */
 128                if (!has_sha1_file(commit->object.sha1))
 129                        commit->object.parsed = 1;
 130                parents = parents->next;
 131        }
 132}
 133
 134static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
 135{
 136        if (revs->no_walk && (obj->flags & UNINTERESTING))
 137                revs->no_walk = 0;
 138        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 139                struct strbuf buf = STRBUF_INIT;
 140                int len = interpret_branch_name(name, &buf);
 141                int st;
 142
 143                if (0 < len && name[len] && buf.len)
 144                        strbuf_addstr(&buf, name + len);
 145                st = add_reflog_for_walk(revs->reflog_info,
 146                                         (struct commit *)obj,
 147                                         buf.buf[0] ? buf.buf: name);
 148                strbuf_release(&buf);
 149                if (st)
 150                        return;
 151        }
 152        add_object_array_with_mode(obj, name, &revs->pending, mode);
 153}
 154
 155void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 156{
 157        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 158}
 159
 160void add_head_to_pending(struct rev_info *revs)
 161{
 162        unsigned char sha1[20];
 163        struct object *obj;
 164        if (get_sha1("HEAD", sha1))
 165                return;
 166        obj = parse_object(sha1);
 167        if (!obj)
 168                return;
 169        add_pending_object(revs, obj, "HEAD");
 170}
 171
 172static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 173{
 174        struct object *object;
 175
 176        object = parse_object(sha1);
 177        if (!object)
 178                die("bad object %s", name);
 179        object->flags |= flags;
 180        return object;
 181}
 182
 183static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 184{
 185        unsigned long flags = object->flags;
 186
 187        /*
 188         * Tag object? Look what it points to..
 189         */
 190        while (object->type == OBJ_TAG) {
 191                struct tag *tag = (struct tag *) object;
 192                if (revs->tag_objects && !(flags & UNINTERESTING))
 193                        add_pending_object(revs, object, tag->tag);
 194                if (!tag->tagged)
 195                        die("bad tag");
 196                object = parse_object(tag->tagged->sha1);
 197                if (!object) {
 198                        if (flags & UNINTERESTING)
 199                                return NULL;
 200                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 201                }
 202        }
 203
 204        /*
 205         * Commit object? Just return it, we'll do all the complex
 206         * reachability crud.
 207         */
 208        if (object->type == OBJ_COMMIT) {
 209                struct commit *commit = (struct commit *)object;
 210                if (parse_commit(commit) < 0)
 211                        die("unable to parse commit %s", name);
 212                if (flags & UNINTERESTING) {
 213                        commit->object.flags |= UNINTERESTING;
 214                        mark_parents_uninteresting(commit);
 215                        revs->limited = 1;
 216                }
 217                if (revs->show_source && !commit->util)
 218                        commit->util = (void *) name;
 219                return commit;
 220        }
 221
 222        /*
 223         * Tree object? Either mark it uninteresting, or add it
 224         * to the list of objects to look at later..
 225         */
 226        if (object->type == OBJ_TREE) {
 227                struct tree *tree = (struct tree *)object;
 228                if (!revs->tree_objects)
 229                        return NULL;
 230                if (flags & UNINTERESTING) {
 231                        mark_tree_uninteresting(tree);
 232                        return NULL;
 233                }
 234                add_pending_object(revs, object, "");
 235                return NULL;
 236        }
 237
 238        /*
 239         * Blob object? You know the drill by now..
 240         */
 241        if (object->type == OBJ_BLOB) {
 242                struct blob *blob = (struct blob *)object;
 243                if (!revs->blob_objects)
 244                        return NULL;
 245                if (flags & UNINTERESTING) {
 246                        mark_blob_uninteresting(blob);
 247                        return NULL;
 248                }
 249                add_pending_object(revs, object, "");
 250                return NULL;
 251        }
 252        die("%s is unknown object", name);
 253}
 254
 255static int everybody_uninteresting(struct commit_list *orig)
 256{
 257        struct commit_list *list = orig;
 258        while (list) {
 259                struct commit *commit = list->item;
 260                list = list->next;
 261                if (commit->object.flags & UNINTERESTING)
 262                        continue;
 263                return 0;
 264        }
 265        return 1;
 266}
 267
 268/*
 269 * The goal is to get REV_TREE_NEW as the result only if the
 270 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 271 * if the whole diff is removal of old data, and otherwise
 272 * REV_TREE_DIFFERENT (of course if the trees are the same we
 273 * want REV_TREE_SAME).
 274 * That means that once we get to REV_TREE_DIFFERENT, we do not
 275 * have to look any further.
 276 */
 277static int tree_difference = REV_TREE_SAME;
 278
 279static void file_add_remove(struct diff_options *options,
 280                    int addremove, unsigned mode,
 281                    const unsigned char *sha1,
 282                    const char *fullpath, unsigned dirty_submodule)
 283{
 284        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 285
 286        tree_difference |= diff;
 287        if (tree_difference == REV_TREE_DIFFERENT)
 288                DIFF_OPT_SET(options, HAS_CHANGES);
 289}
 290
 291static void file_change(struct diff_options *options,
 292                 unsigned old_mode, unsigned new_mode,
 293                 const unsigned char *old_sha1,
 294                 const unsigned char *new_sha1,
 295                 const char *fullpath,
 296                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 297{
 298        tree_difference = REV_TREE_DIFFERENT;
 299        DIFF_OPT_SET(options, HAS_CHANGES);
 300}
 301
 302static int rev_compare_tree(struct rev_info *revs, struct commit *parent, struct commit *commit)
 303{
 304        struct tree *t1 = parent->tree;
 305        struct tree *t2 = commit->tree;
 306
 307        if (!t1)
 308                return REV_TREE_NEW;
 309        if (!t2)
 310                return REV_TREE_OLD;
 311
 312        if (revs->simplify_by_decoration) {
 313                /*
 314                 * If we are simplifying by decoration, then the commit
 315                 * is worth showing if it has a tag pointing at it.
 316                 */
 317                if (lookup_decoration(&name_decoration, &commit->object))
 318                        return REV_TREE_DIFFERENT;
 319                /*
 320                 * A commit that is not pointed by a tag is uninteresting
 321                 * if we are not limited by path.  This means that you will
 322                 * see the usual "commits that touch the paths" plus any
 323                 * tagged commit by specifying both --simplify-by-decoration
 324                 * and pathspec.
 325                 */
 326                if (!revs->prune_data.nr)
 327                        return REV_TREE_SAME;
 328        }
 329
 330        tree_difference = REV_TREE_SAME;
 331        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 332        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 333                           &revs->pruning) < 0)
 334                return REV_TREE_DIFFERENT;
 335        return tree_difference;
 336}
 337
 338static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 339{
 340        int retval;
 341        void *tree;
 342        unsigned long size;
 343        struct tree_desc empty, real;
 344        struct tree *t1 = commit->tree;
 345
 346        if (!t1)
 347                return 0;
 348
 349        tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
 350        if (!tree)
 351                return 0;
 352        init_tree_desc(&real, tree, size);
 353        init_tree_desc(&empty, "", 0);
 354
 355        tree_difference = REV_TREE_SAME;
 356        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 357        retval = diff_tree(&empty, &real, "", &revs->pruning);
 358        free(tree);
 359
 360        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 361}
 362
 363static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 364{
 365        struct commit_list **pp, *parent;
 366        int tree_changed = 0, tree_same = 0;
 367
 368        /*
 369         * If we don't do pruning, everything is interesting
 370         */
 371        if (!revs->prune)
 372                return;
 373
 374        if (!commit->tree)
 375                return;
 376
 377        if (!commit->parents) {
 378                if (rev_same_tree_as_empty(revs, commit))
 379                        commit->object.flags |= TREESAME;
 380                return;
 381        }
 382
 383        /*
 384         * Normal non-merge commit? If we don't want to make the
 385         * history dense, we consider it always to be a change..
 386         */
 387        if (!revs->dense && !commit->parents->next)
 388                return;
 389
 390        pp = &commit->parents;
 391        while ((parent = *pp) != NULL) {
 392                struct commit *p = parent->item;
 393
 394                if (parse_commit(p) < 0)
 395                        die("cannot simplify commit %s (because of %s)",
 396                            sha1_to_hex(commit->object.sha1),
 397                            sha1_to_hex(p->object.sha1));
 398                switch (rev_compare_tree(revs, p, commit)) {
 399                case REV_TREE_SAME:
 400                        tree_same = 1;
 401                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 402                                /* Even if a merge with an uninteresting
 403                                 * side branch brought the entire change
 404                                 * we are interested in, we do not want
 405                                 * to lose the other branches of this
 406                                 * merge, so we just keep going.
 407                                 */
 408                                pp = &parent->next;
 409                                continue;
 410                        }
 411                        parent->next = NULL;
 412                        commit->parents = parent;
 413                        commit->object.flags |= TREESAME;
 414                        return;
 415
 416                case REV_TREE_NEW:
 417                        if (revs->remove_empty_trees &&
 418                            rev_same_tree_as_empty(revs, p)) {
 419                                /* We are adding all the specified
 420                                 * paths from this parent, so the
 421                                 * history beyond this parent is not
 422                                 * interesting.  Remove its parents
 423                                 * (they are grandparents for us).
 424                                 * IOW, we pretend this parent is a
 425                                 * "root" commit.
 426                                 */
 427                                if (parse_commit(p) < 0)
 428                                        die("cannot simplify commit %s (invalid %s)",
 429                                            sha1_to_hex(commit->object.sha1),
 430                                            sha1_to_hex(p->object.sha1));
 431                                p->parents = NULL;
 432                        }
 433                /* fallthrough */
 434                case REV_TREE_OLD:
 435                case REV_TREE_DIFFERENT:
 436                        tree_changed = 1;
 437                        pp = &parent->next;
 438                        continue;
 439                }
 440                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 441        }
 442        if (tree_changed && !tree_same)
 443                return;
 444        commit->object.flags |= TREESAME;
 445}
 446
 447static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 448                    struct commit_list *cached_base, struct commit_list **cache)
 449{
 450        struct commit_list *new_entry;
 451
 452        if (cached_base && p->date < cached_base->item->date)
 453                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 454        else
 455                new_entry = commit_list_insert_by_date(p, head);
 456
 457        if (cache && (!*cache || p->date < (*cache)->item->date))
 458                *cache = new_entry;
 459}
 460
 461static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 462                    struct commit_list **list, struct commit_list **cache_ptr)
 463{
 464        struct commit_list *parent = commit->parents;
 465        unsigned left_flag;
 466        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 467
 468        if (commit->object.flags & ADDED)
 469                return 0;
 470        commit->object.flags |= ADDED;
 471
 472        /*
 473         * If the commit is uninteresting, don't try to
 474         * prune parents - we want the maximal uninteresting
 475         * set.
 476         *
 477         * Normally we haven't parsed the parent
 478         * yet, so we won't have a parent of a parent
 479         * here. However, it may turn out that we've
 480         * reached this commit some other way (where it
 481         * wasn't uninteresting), in which case we need
 482         * to mark its parents recursively too..
 483         */
 484        if (commit->object.flags & UNINTERESTING) {
 485                while (parent) {
 486                        struct commit *p = parent->item;
 487                        parent = parent->next;
 488                        if (p)
 489                                p->object.flags |= UNINTERESTING;
 490                        if (parse_commit(p) < 0)
 491                                continue;
 492                        if (p->parents)
 493                                mark_parents_uninteresting(p);
 494                        if (p->object.flags & SEEN)
 495                                continue;
 496                        p->object.flags |= SEEN;
 497                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 498                }
 499                return 0;
 500        }
 501
 502        /*
 503         * Ok, the commit wasn't uninteresting. Try to
 504         * simplify the commit history and find the parent
 505         * that has no differences in the path set if one exists.
 506         */
 507        try_to_simplify_commit(revs, commit);
 508
 509        if (revs->no_walk)
 510                return 0;
 511
 512        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 513
 514        for (parent = commit->parents; parent; parent = parent->next) {
 515                struct commit *p = parent->item;
 516
 517                if (parse_commit(p) < 0)
 518                        return -1;
 519                if (revs->show_source && !p->util)
 520                        p->util = commit->util;
 521                p->object.flags |= left_flag;
 522                if (!(p->object.flags & SEEN)) {
 523                        p->object.flags |= SEEN;
 524                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 525                }
 526                if (revs->first_parent_only)
 527                        break;
 528        }
 529        return 0;
 530}
 531
 532static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 533{
 534        struct commit_list *p;
 535        int left_count = 0, right_count = 0;
 536        int left_first;
 537        struct patch_ids ids;
 538        unsigned cherry_flag;
 539
 540        /* First count the commits on the left and on the right */
 541        for (p = list; p; p = p->next) {
 542                struct commit *commit = p->item;
 543                unsigned flags = commit->object.flags;
 544                if (flags & BOUNDARY)
 545                        ;
 546                else if (flags & SYMMETRIC_LEFT)
 547                        left_count++;
 548                else
 549                        right_count++;
 550        }
 551
 552        if (!left_count || !right_count)
 553                return;
 554
 555        left_first = left_count < right_count;
 556        init_patch_ids(&ids);
 557        ids.diffopts.pathspec = revs->diffopt.pathspec;
 558
 559        /* Compute patch-ids for one side */
 560        for (p = list; p; p = p->next) {
 561                struct commit *commit = p->item;
 562                unsigned flags = commit->object.flags;
 563
 564                if (flags & BOUNDARY)
 565                        continue;
 566                /*
 567                 * If we have fewer left, left_first is set and we omit
 568                 * commits on the right branch in this loop.  If we have
 569                 * fewer right, we skip the left ones.
 570                 */
 571                if (left_first != !!(flags & SYMMETRIC_LEFT))
 572                        continue;
 573                commit->util = add_commit_patch_id(commit, &ids);
 574        }
 575
 576        /* either cherry_mark or cherry_pick are true */
 577        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 578
 579        /* Check the other side */
 580        for (p = list; p; p = p->next) {
 581                struct commit *commit = p->item;
 582                struct patch_id *id;
 583                unsigned flags = commit->object.flags;
 584
 585                if (flags & BOUNDARY)
 586                        continue;
 587                /*
 588                 * If we have fewer left, left_first is set and we omit
 589                 * commits on the left branch in this loop.
 590                 */
 591                if (left_first == !!(flags & SYMMETRIC_LEFT))
 592                        continue;
 593
 594                /*
 595                 * Have we seen the same patch id?
 596                 */
 597                id = has_commit_patch_id(commit, &ids);
 598                if (!id)
 599                        continue;
 600                id->seen = 1;
 601                commit->object.flags |= cherry_flag;
 602        }
 603
 604        /* Now check the original side for seen ones */
 605        for (p = list; p; p = p->next) {
 606                struct commit *commit = p->item;
 607                struct patch_id *ent;
 608
 609                ent = commit->util;
 610                if (!ent)
 611                        continue;
 612                if (ent->seen)
 613                        commit->object.flags |= cherry_flag;
 614                commit->util = NULL;
 615        }
 616
 617        free_patch_ids(&ids);
 618}
 619
 620/* How many extra uninteresting commits we want to see.. */
 621#define SLOP 5
 622
 623static int still_interesting(struct commit_list *src, unsigned long date, int slop)
 624{
 625        /*
 626         * No source list at all? We're definitely done..
 627         */
 628        if (!src)
 629                return 0;
 630
 631        /*
 632         * Does the destination list contain entries with a date
 633         * before the source list? Definitely _not_ done.
 634         */
 635        if (date < src->item->date)
 636                return SLOP;
 637
 638        /*
 639         * Does the source list still have interesting commits in
 640         * it? Definitely not done..
 641         */
 642        if (!everybody_uninteresting(src))
 643                return SLOP;
 644
 645        /* Ok, we're closing in.. */
 646        return slop-1;
 647}
 648
 649/*
 650 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 651 * of B but not ancestors of A but further limits the result to those
 652 * that are descendants of A.  This takes the list of bottom commits and
 653 * the result of "A..B" without --ancestry-path, and limits the latter
 654 * further to the ones that can reach one of the commits in "bottom".
 655 */
 656static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 657{
 658        struct commit_list *p;
 659        struct commit_list *rlist = NULL;
 660        int made_progress;
 661
 662        /*
 663         * Reverse the list so that it will be likely that we would
 664         * process parents before children.
 665         */
 666        for (p = list; p; p = p->next)
 667                commit_list_insert(p->item, &rlist);
 668
 669        for (p = bottom; p; p = p->next)
 670                p->item->object.flags |= TMP_MARK;
 671
 672        /*
 673         * Mark the ones that can reach bottom commits in "list",
 674         * in a bottom-up fashion.
 675         */
 676        do {
 677                made_progress = 0;
 678                for (p = rlist; p; p = p->next) {
 679                        struct commit *c = p->item;
 680                        struct commit_list *parents;
 681                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 682                                continue;
 683                        for (parents = c->parents;
 684                             parents;
 685                             parents = parents->next) {
 686                                if (!(parents->item->object.flags & TMP_MARK))
 687                                        continue;
 688                                c->object.flags |= TMP_MARK;
 689                                made_progress = 1;
 690                                break;
 691                        }
 692                }
 693        } while (made_progress);
 694
 695        /*
 696         * NEEDSWORK: decide if we want to remove parents that are
 697         * not marked with TMP_MARK from commit->parents for commits
 698         * in the resulting list.  We may not want to do that, though.
 699         */
 700
 701        /*
 702         * The ones that are not marked with TMP_MARK are uninteresting
 703         */
 704        for (p = list; p; p = p->next) {
 705                struct commit *c = p->item;
 706                if (c->object.flags & TMP_MARK)
 707                        continue;
 708                c->object.flags |= UNINTERESTING;
 709        }
 710
 711        /* We are done with the TMP_MARK */
 712        for (p = list; p; p = p->next)
 713                p->item->object.flags &= ~TMP_MARK;
 714        for (p = bottom; p; p = p->next)
 715                p->item->object.flags &= ~TMP_MARK;
 716        free_commit_list(rlist);
 717}
 718
 719/*
 720 * Before walking the history, keep the set of "negative" refs the
 721 * caller has asked to exclude.
 722 *
 723 * This is used to compute "rev-list --ancestry-path A..B", as we need
 724 * to filter the result of "A..B" further to the ones that can actually
 725 * reach A.
 726 */
 727static struct commit_list *collect_bottom_commits(struct commit_list *list)
 728{
 729        struct commit_list *elem, *bottom = NULL;
 730        for (elem = list; elem; elem = elem->next)
 731                if (elem->item->object.flags & UNINTERESTING)
 732                        commit_list_insert(elem->item, &bottom);
 733        return bottom;
 734}
 735
 736/* Assumes either left_only or right_only is set */
 737static void limit_left_right(struct commit_list *list, struct rev_info *revs)
 738{
 739        struct commit_list *p;
 740
 741        for (p = list; p; p = p->next) {
 742                struct commit *commit = p->item;
 743
 744                if (revs->right_only) {
 745                        if (commit->object.flags & SYMMETRIC_LEFT)
 746                                commit->object.flags |= SHOWN;
 747                } else  /* revs->left_only is set */
 748                        if (!(commit->object.flags & SYMMETRIC_LEFT))
 749                                commit->object.flags |= SHOWN;
 750        }
 751}
 752
 753static int limit_list(struct rev_info *revs)
 754{
 755        int slop = SLOP;
 756        unsigned long date = ~0ul;
 757        struct commit_list *list = revs->commits;
 758        struct commit_list *newlist = NULL;
 759        struct commit_list **p = &newlist;
 760        struct commit_list *bottom = NULL;
 761
 762        if (revs->ancestry_path) {
 763                bottom = collect_bottom_commits(list);
 764                if (!bottom)
 765                        die("--ancestry-path given but there are no bottom commits");
 766        }
 767
 768        while (list) {
 769                struct commit_list *entry = list;
 770                struct commit *commit = list->item;
 771                struct object *obj = &commit->object;
 772                show_early_output_fn_t show;
 773
 774                list = list->next;
 775                free(entry);
 776
 777                if (revs->max_age != -1 && (commit->date < revs->max_age))
 778                        obj->flags |= UNINTERESTING;
 779                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
 780                        return -1;
 781                if (obj->flags & UNINTERESTING) {
 782                        mark_parents_uninteresting(commit);
 783                        if (revs->show_all)
 784                                p = &commit_list_insert(commit, p)->next;
 785                        slop = still_interesting(list, date, slop);
 786                        if (slop)
 787                                continue;
 788                        /* If showing all, add the whole pending list to the end */
 789                        if (revs->show_all)
 790                                *p = list;
 791                        break;
 792                }
 793                if (revs->min_age != -1 && (commit->date > revs->min_age))
 794                        continue;
 795                date = commit->date;
 796                p = &commit_list_insert(commit, p)->next;
 797
 798                show = show_early_output;
 799                if (!show)
 800                        continue;
 801
 802                show(revs, newlist);
 803                show_early_output = NULL;
 804        }
 805        if (revs->cherry_pick || revs->cherry_mark)
 806                cherry_pick_list(newlist, revs);
 807
 808        if (revs->left_only || revs->right_only)
 809                limit_left_right(newlist, revs);
 810
 811        if (bottom) {
 812                limit_to_ancestry(bottom, newlist);
 813                free_commit_list(bottom);
 814        }
 815
 816        revs->commits = newlist;
 817        return 0;
 818}
 819
 820struct all_refs_cb {
 821        int all_flags;
 822        int warned_bad_reflog;
 823        struct rev_info *all_revs;
 824        const char *name_for_errormsg;
 825};
 826
 827static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 828{
 829        struct all_refs_cb *cb = cb_data;
 830        struct object *object = get_reference(cb->all_revs, path, sha1,
 831                                              cb->all_flags);
 832        add_pending_object(cb->all_revs, object, path);
 833        return 0;
 834}
 835
 836static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
 837        unsigned flags)
 838{
 839        cb->all_revs = revs;
 840        cb->all_flags = flags;
 841}
 842
 843static void handle_refs(const char *submodule, struct rev_info *revs, unsigned flags,
 844                int (*for_each)(const char *, each_ref_fn, void *))
 845{
 846        struct all_refs_cb cb;
 847        init_all_refs_cb(&cb, revs, flags);
 848        for_each(submodule, handle_one_ref, &cb);
 849}
 850
 851static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 852{
 853        struct all_refs_cb *cb = cb_data;
 854        if (!is_null_sha1(sha1)) {
 855                struct object *o = parse_object(sha1);
 856                if (o) {
 857                        o->flags |= cb->all_flags;
 858                        add_pending_object(cb->all_revs, o, "");
 859                }
 860                else if (!cb->warned_bad_reflog) {
 861                        warning("reflog of '%s' references pruned commits",
 862                                cb->name_for_errormsg);
 863                        cb->warned_bad_reflog = 1;
 864                }
 865        }
 866}
 867
 868static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 869                const char *email, unsigned long timestamp, int tz,
 870                const char *message, void *cb_data)
 871{
 872        handle_one_reflog_commit(osha1, cb_data);
 873        handle_one_reflog_commit(nsha1, cb_data);
 874        return 0;
 875}
 876
 877static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 878{
 879        struct all_refs_cb *cb = cb_data;
 880        cb->warned_bad_reflog = 0;
 881        cb->name_for_errormsg = path;
 882        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
 883        return 0;
 884}
 885
 886static void handle_reflog(struct rev_info *revs, unsigned flags)
 887{
 888        struct all_refs_cb cb;
 889        cb.all_revs = revs;
 890        cb.all_flags = flags;
 891        for_each_reflog(handle_one_reflog, &cb);
 892}
 893
 894static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 895{
 896        unsigned char sha1[20];
 897        struct object *it;
 898        struct commit *commit;
 899        struct commit_list *parents;
 900
 901        if (*arg == '^') {
 902                flags ^= UNINTERESTING;
 903                arg++;
 904        }
 905        if (get_sha1(arg, sha1))
 906                return 0;
 907        while (1) {
 908                it = get_reference(revs, arg, sha1, 0);
 909                if (it->type != OBJ_TAG)
 910                        break;
 911                if (!((struct tag*)it)->tagged)
 912                        return 0;
 913                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 914        }
 915        if (it->type != OBJ_COMMIT)
 916                return 0;
 917        commit = (struct commit *)it;
 918        for (parents = commit->parents; parents; parents = parents->next) {
 919                it = &parents->item->object;
 920                it->flags |= flags;
 921                add_pending_object(revs, it, arg);
 922        }
 923        return 1;
 924}
 925
 926void init_revisions(struct rev_info *revs, const char *prefix)
 927{
 928        memset(revs, 0, sizeof(*revs));
 929
 930        revs->abbrev = DEFAULT_ABBREV;
 931        revs->ignore_merges = 1;
 932        revs->simplify_history = 1;
 933        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
 934        DIFF_OPT_SET(&revs->pruning, QUICK);
 935        revs->pruning.add_remove = file_add_remove;
 936        revs->pruning.change = file_change;
 937        revs->lifo = 1;
 938        revs->dense = 1;
 939        revs->prefix = prefix;
 940        revs->max_age = -1;
 941        revs->min_age = -1;
 942        revs->skip_count = -1;
 943        revs->max_count = -1;
 944        revs->max_parents = -1;
 945
 946        revs->commit_format = CMIT_FMT_DEFAULT;
 947
 948        revs->grep_filter.status_only = 1;
 949        revs->grep_filter.pattern_tail = &(revs->grep_filter.pattern_list);
 950        revs->grep_filter.header_tail = &(revs->grep_filter.header_list);
 951        revs->grep_filter.regflags = REG_NEWLINE;
 952
 953        diff_setup(&revs->diffopt);
 954        if (prefix && !revs->diffopt.prefix) {
 955                revs->diffopt.prefix = prefix;
 956                revs->diffopt.prefix_length = strlen(prefix);
 957        }
 958}
 959
 960static void add_pending_commit_list(struct rev_info *revs,
 961                                    struct commit_list *commit_list,
 962                                    unsigned int flags)
 963{
 964        while (commit_list) {
 965                struct object *object = &commit_list->item->object;
 966                object->flags |= flags;
 967                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 968                commit_list = commit_list->next;
 969        }
 970}
 971
 972static void prepare_show_merge(struct rev_info *revs)
 973{
 974        struct commit_list *bases;
 975        struct commit *head, *other;
 976        unsigned char sha1[20];
 977        const char **prune = NULL;
 978        int i, prune_num = 1; /* counting terminating NULL */
 979
 980        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 981                die("--merge without HEAD?");
 982        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 983                die("--merge without MERGE_HEAD?");
 984        add_pending_object(revs, &head->object, "HEAD");
 985        add_pending_object(revs, &other->object, "MERGE_HEAD");
 986        bases = get_merge_bases(head, other, 1);
 987        add_pending_commit_list(revs, bases, UNINTERESTING);
 988        free_commit_list(bases);
 989        head->object.flags |= SYMMETRIC_LEFT;
 990
 991        if (!active_nr)
 992                read_cache();
 993        for (i = 0; i < active_nr; i++) {
 994                struct cache_entry *ce = active_cache[i];
 995                if (!ce_stage(ce))
 996                        continue;
 997                if (ce_path_match(ce, &revs->prune_data)) {
 998                        prune_num++;
 999                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
1000                        prune[prune_num-2] = ce->name;
1001                        prune[prune_num-1] = NULL;
1002                }
1003                while ((i+1 < active_nr) &&
1004                       ce_same_name(ce, active_cache[i+1]))
1005                        i++;
1006        }
1007        free_pathspec(&revs->prune_data);
1008        init_pathspec(&revs->prune_data, prune);
1009        revs->limited = 1;
1010}
1011
1012int handle_revision_arg(const char *arg, struct rev_info *revs,
1013                        int flags,
1014                        int cant_be_filename)
1015{
1016        unsigned mode;
1017        char *dotdot;
1018        struct object *object;
1019        unsigned char sha1[20];
1020        int local_flags;
1021
1022        dotdot = strstr(arg, "..");
1023        if (dotdot) {
1024                unsigned char from_sha1[20];
1025                const char *next = dotdot + 2;
1026                const char *this = arg;
1027                int symmetric = *next == '.';
1028                unsigned int flags_exclude = flags ^ UNINTERESTING;
1029
1030                *dotdot = 0;
1031                next += symmetric;
1032
1033                if (!*next)
1034                        next = "HEAD";
1035                if (dotdot == arg)
1036                        this = "HEAD";
1037                if (!get_sha1(this, from_sha1) &&
1038                    !get_sha1(next, sha1)) {
1039                        struct commit *a, *b;
1040                        struct commit_list *exclude;
1041
1042                        a = lookup_commit_reference(from_sha1);
1043                        b = lookup_commit_reference(sha1);
1044                        if (!a || !b) {
1045                                die(symmetric ?
1046                                    "Invalid symmetric difference expression %s...%s" :
1047                                    "Invalid revision range %s..%s",
1048                                    arg, next);
1049                        }
1050
1051                        if (!cant_be_filename) {
1052                                *dotdot = '.';
1053                                verify_non_filename(revs->prefix, arg);
1054                        }
1055
1056                        if (symmetric) {
1057                                exclude = get_merge_bases(a, b, 1);
1058                                add_pending_commit_list(revs, exclude,
1059                                                        flags_exclude);
1060                                free_commit_list(exclude);
1061                                a->object.flags |= flags | SYMMETRIC_LEFT;
1062                        } else
1063                                a->object.flags |= flags_exclude;
1064                        b->object.flags |= flags;
1065                        add_pending_object(revs, &a->object, this);
1066                        add_pending_object(revs, &b->object, next);
1067                        return 0;
1068                }
1069                *dotdot = '.';
1070        }
1071        dotdot = strstr(arg, "^@");
1072        if (dotdot && !dotdot[2]) {
1073                *dotdot = 0;
1074                if (add_parents_only(revs, arg, flags))
1075                        return 0;
1076                *dotdot = '^';
1077        }
1078        dotdot = strstr(arg, "^!");
1079        if (dotdot && !dotdot[2]) {
1080                *dotdot = 0;
1081                if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
1082                        *dotdot = '^';
1083        }
1084
1085        local_flags = 0;
1086        if (*arg == '^') {
1087                local_flags = UNINTERESTING;
1088                arg++;
1089        }
1090        if (get_sha1_with_mode(arg, sha1, &mode))
1091                return -1;
1092        if (!cant_be_filename)
1093                verify_non_filename(revs->prefix, arg);
1094        object = get_reference(revs, arg, sha1, flags ^ local_flags);
1095        add_pending_object_with_mode(revs, object, arg, mode);
1096        return 0;
1097}
1098
1099static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb, const char ***prune_data)
1100{
1101        const char **prune = *prune_data;
1102        int prune_nr;
1103        int prune_alloc;
1104
1105        /* count existing ones */
1106        if (!prune)
1107                prune_nr = 0;
1108        else
1109                for (prune_nr = 0; prune[prune_nr]; prune_nr++)
1110                        ;
1111        prune_alloc = prune_nr; /* not really, but we do not know */
1112
1113        while (strbuf_getwholeline(sb, stdin, '\n') != EOF) {
1114                int len = sb->len;
1115                if (len && sb->buf[len - 1] == '\n')
1116                        sb->buf[--len] = '\0';
1117                ALLOC_GROW(prune, prune_nr+1, prune_alloc);
1118                prune[prune_nr++] = xstrdup(sb->buf);
1119        }
1120        if (prune) {
1121                ALLOC_GROW(prune, prune_nr+1, prune_alloc);
1122                prune[prune_nr] = NULL;
1123        }
1124        *prune_data = prune;
1125}
1126
1127static void read_revisions_from_stdin(struct rev_info *revs, const char ***prune)
1128{
1129        struct strbuf sb;
1130        int seen_dashdash = 0;
1131
1132        strbuf_init(&sb, 1000);
1133        while (strbuf_getwholeline(&sb, stdin, '\n') != EOF) {
1134                int len = sb.len;
1135                if (len && sb.buf[len - 1] == '\n')
1136                        sb.buf[--len] = '\0';
1137                if (!len)
1138                        break;
1139                if (sb.buf[0] == '-') {
1140                        if (len == 2 && sb.buf[1] == '-') {
1141                                seen_dashdash = 1;
1142                                break;
1143                        }
1144                        die("options not supported in --stdin mode");
1145                }
1146                if (handle_revision_arg(sb.buf, revs, 0, 1))
1147                        die("bad revision '%s'", sb.buf);
1148        }
1149        if (seen_dashdash)
1150                read_pathspec_from_stdin(revs, &sb, prune);
1151        strbuf_release(&sb);
1152}
1153
1154static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1155{
1156        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1157}
1158
1159static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1160{
1161        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1162}
1163
1164static void add_message_grep(struct rev_info *revs, const char *pattern)
1165{
1166        add_grep(revs, pattern, GREP_PATTERN_BODY);
1167}
1168
1169static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1170                               int *unkc, const char **unkv)
1171{
1172        const char *arg = argv[0];
1173        const char *optarg;
1174        int argcount;
1175
1176        /* pseudo revision arguments */
1177        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1178            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1179            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1180            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1181            !strcmp(arg, "--bisect"))
1182        {
1183                unkv[(*unkc)++] = arg;
1184                return 1;
1185        }
1186
1187        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1188                revs->max_count = atoi(optarg);
1189                revs->no_walk = 0;
1190                return argcount;
1191        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1192                revs->skip_count = atoi(optarg);
1193                return argcount;
1194        } else if ((*arg == '-') && isdigit(arg[1])) {
1195        /* accept -<digit>, like traditional "head" */
1196                revs->max_count = atoi(arg + 1);
1197                revs->no_walk = 0;
1198        } else if (!strcmp(arg, "-n")) {
1199                if (argc <= 1)
1200                        return error("-n requires an argument");
1201                revs->max_count = atoi(argv[1]);
1202                revs->no_walk = 0;
1203                return 2;
1204        } else if (!prefixcmp(arg, "-n")) {
1205                revs->max_count = atoi(arg + 2);
1206                revs->no_walk = 0;
1207        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1208                revs->max_age = atoi(optarg);
1209                return argcount;
1210        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1211                revs->max_age = approxidate(optarg);
1212                return argcount;
1213        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1214                revs->max_age = approxidate(optarg);
1215                return argcount;
1216        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1217                revs->min_age = atoi(optarg);
1218                return argcount;
1219        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1220                revs->min_age = approxidate(optarg);
1221                return argcount;
1222        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1223                revs->min_age = approxidate(optarg);
1224                return argcount;
1225        } else if (!strcmp(arg, "--first-parent")) {
1226                revs->first_parent_only = 1;
1227        } else if (!strcmp(arg, "--ancestry-path")) {
1228                revs->ancestry_path = 1;
1229                revs->simplify_history = 0;
1230                revs->limited = 1;
1231        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1232                init_reflog_walk(&revs->reflog_info);
1233        } else if (!strcmp(arg, "--default")) {
1234                if (argc <= 1)
1235                        return error("bad --default argument");
1236                revs->def = argv[1];
1237                return 2;
1238        } else if (!strcmp(arg, "--merge")) {
1239                revs->show_merge = 1;
1240        } else if (!strcmp(arg, "--topo-order")) {
1241                revs->lifo = 1;
1242                revs->topo_order = 1;
1243        } else if (!strcmp(arg, "--simplify-merges")) {
1244                revs->simplify_merges = 1;
1245                revs->rewrite_parents = 1;
1246                revs->simplify_history = 0;
1247                revs->limited = 1;
1248        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1249                revs->simplify_merges = 1;
1250                revs->rewrite_parents = 1;
1251                revs->simplify_history = 0;
1252                revs->simplify_by_decoration = 1;
1253                revs->limited = 1;
1254                revs->prune = 1;
1255                load_ref_decorations(DECORATE_SHORT_REFS);
1256        } else if (!strcmp(arg, "--date-order")) {
1257                revs->lifo = 0;
1258                revs->topo_order = 1;
1259        } else if (!prefixcmp(arg, "--early-output")) {
1260                int count = 100;
1261                switch (arg[14]) {
1262                case '=':
1263                        count = atoi(arg+15);
1264                        /* Fallthrough */
1265                case 0:
1266                        revs->topo_order = 1;
1267                       revs->early_output = count;
1268                }
1269        } else if (!strcmp(arg, "--parents")) {
1270                revs->rewrite_parents = 1;
1271                revs->print_parents = 1;
1272        } else if (!strcmp(arg, "--dense")) {
1273                revs->dense = 1;
1274        } else if (!strcmp(arg, "--sparse")) {
1275                revs->dense = 0;
1276        } else if (!strcmp(arg, "--show-all")) {
1277                revs->show_all = 1;
1278        } else if (!strcmp(arg, "--remove-empty")) {
1279                revs->remove_empty_trees = 1;
1280        } else if (!strcmp(arg, "--merges")) {
1281                revs->min_parents = 2;
1282        } else if (!strcmp(arg, "--no-merges")) {
1283                revs->max_parents = 1;
1284        } else if (!prefixcmp(arg, "--min-parents=")) {
1285                revs->min_parents = atoi(arg+14);
1286        } else if (!prefixcmp(arg, "--no-min-parents")) {
1287                revs->min_parents = 0;
1288        } else if (!prefixcmp(arg, "--max-parents=")) {
1289                revs->max_parents = atoi(arg+14);
1290        } else if (!prefixcmp(arg, "--no-max-parents")) {
1291                revs->max_parents = -1;
1292        } else if (!strcmp(arg, "--boundary")) {
1293                revs->boundary = 1;
1294        } else if (!strcmp(arg, "--left-right")) {
1295                revs->left_right = 1;
1296        } else if (!strcmp(arg, "--left-only")) {
1297                if (revs->right_only)
1298                        die("--left-only is incompatible with --right-only"
1299                            " or --cherry");
1300                revs->left_only = 1;
1301        } else if (!strcmp(arg, "--right-only")) {
1302                if (revs->left_only)
1303                        die("--right-only is incompatible with --left-only");
1304                revs->right_only = 1;
1305        } else if (!strcmp(arg, "--cherry")) {
1306                if (revs->left_only)
1307                        die("--cherry is incompatible with --left-only");
1308                revs->cherry_mark = 1;
1309                revs->right_only = 1;
1310                revs->max_parents = 1;
1311                revs->limited = 1;
1312        } else if (!strcmp(arg, "--count")) {
1313                revs->count = 1;
1314        } else if (!strcmp(arg, "--cherry-mark")) {
1315                if (revs->cherry_pick)
1316                        die("--cherry-mark is incompatible with --cherry-pick");
1317                revs->cherry_mark = 1;
1318                revs->limited = 1; /* needs limit_list() */
1319        } else if (!strcmp(arg, "--cherry-pick")) {
1320                if (revs->cherry_mark)
1321                        die("--cherry-pick is incompatible with --cherry-mark");
1322                revs->cherry_pick = 1;
1323                revs->limited = 1;
1324        } else if (!strcmp(arg, "--objects")) {
1325                revs->tag_objects = 1;
1326                revs->tree_objects = 1;
1327                revs->blob_objects = 1;
1328        } else if (!strcmp(arg, "--objects-edge")) {
1329                revs->tag_objects = 1;
1330                revs->tree_objects = 1;
1331                revs->blob_objects = 1;
1332                revs->edge_hint = 1;
1333        } else if (!strcmp(arg, "--unpacked")) {
1334                revs->unpacked = 1;
1335        } else if (!prefixcmp(arg, "--unpacked=")) {
1336                die("--unpacked=<packfile> no longer supported.");
1337        } else if (!strcmp(arg, "-r")) {
1338                revs->diff = 1;
1339                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1340        } else if (!strcmp(arg, "-t")) {
1341                revs->diff = 1;
1342                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1343                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1344        } else if (!strcmp(arg, "-m")) {
1345                revs->ignore_merges = 0;
1346        } else if (!strcmp(arg, "-c")) {
1347                revs->diff = 1;
1348                revs->dense_combined_merges = 0;
1349                revs->combine_merges = 1;
1350        } else if (!strcmp(arg, "--cc")) {
1351                revs->diff = 1;
1352                revs->dense_combined_merges = 1;
1353                revs->combine_merges = 1;
1354        } else if (!strcmp(arg, "-v")) {
1355                revs->verbose_header = 1;
1356        } else if (!strcmp(arg, "--pretty")) {
1357                revs->verbose_header = 1;
1358                revs->pretty_given = 1;
1359                get_commit_format(arg+8, revs);
1360        } else if (!prefixcmp(arg, "--pretty=") || !prefixcmp(arg, "--format=")) {
1361                /*
1362                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1363                 * not allowed, since the argument is optional.
1364                 */
1365                revs->verbose_header = 1;
1366                revs->pretty_given = 1;
1367                get_commit_format(arg+9, revs);
1368        } else if (!strcmp(arg, "--show-notes")) {
1369                revs->show_notes = 1;
1370                revs->show_notes_given = 1;
1371        } else if (!prefixcmp(arg, "--show-notes=")) {
1372                struct strbuf buf = STRBUF_INIT;
1373                revs->show_notes = 1;
1374                revs->show_notes_given = 1;
1375                if (!revs->notes_opt.extra_notes_refs)
1376                        revs->notes_opt.extra_notes_refs = xcalloc(1, sizeof(struct string_list));
1377                if (!prefixcmp(arg+13, "refs/"))
1378                        /* happy */;
1379                else if (!prefixcmp(arg+13, "notes/"))
1380                        strbuf_addstr(&buf, "refs/");
1381                else
1382                        strbuf_addstr(&buf, "refs/notes/");
1383                strbuf_addstr(&buf, arg+13);
1384                string_list_append(revs->notes_opt.extra_notes_refs,
1385                                   strbuf_detach(&buf, NULL));
1386        } else if (!strcmp(arg, "--no-notes")) {
1387                revs->show_notes = 0;
1388                revs->show_notes_given = 1;
1389        } else if (!strcmp(arg, "--standard-notes")) {
1390                revs->show_notes_given = 1;
1391                revs->notes_opt.suppress_default_notes = 0;
1392        } else if (!strcmp(arg, "--no-standard-notes")) {
1393                revs->notes_opt.suppress_default_notes = 1;
1394        } else if (!strcmp(arg, "--oneline")) {
1395                revs->verbose_header = 1;
1396                get_commit_format("oneline", revs);
1397                revs->pretty_given = 1;
1398                revs->abbrev_commit = 1;
1399        } else if (!strcmp(arg, "--graph")) {
1400                revs->topo_order = 1;
1401                revs->rewrite_parents = 1;
1402                revs->graph = graph_init(revs);
1403        } else if (!strcmp(arg, "--root")) {
1404                revs->show_root_diff = 1;
1405        } else if (!strcmp(arg, "--no-commit-id")) {
1406                revs->no_commit_id = 1;
1407        } else if (!strcmp(arg, "--always")) {
1408                revs->always_show_header = 1;
1409        } else if (!strcmp(arg, "--no-abbrev")) {
1410                revs->abbrev = 0;
1411        } else if (!strcmp(arg, "--abbrev")) {
1412                revs->abbrev = DEFAULT_ABBREV;
1413        } else if (!prefixcmp(arg, "--abbrev=")) {
1414                revs->abbrev = strtoul(arg + 9, NULL, 10);
1415                if (revs->abbrev < MINIMUM_ABBREV)
1416                        revs->abbrev = MINIMUM_ABBREV;
1417                else if (revs->abbrev > 40)
1418                        revs->abbrev = 40;
1419        } else if (!strcmp(arg, "--abbrev-commit")) {
1420                revs->abbrev_commit = 1;
1421        } else if (!strcmp(arg, "--full-diff")) {
1422                revs->diff = 1;
1423                revs->full_diff = 1;
1424        } else if (!strcmp(arg, "--full-history")) {
1425                revs->simplify_history = 0;
1426        } else if (!strcmp(arg, "--relative-date")) {
1427                revs->date_mode = DATE_RELATIVE;
1428                revs->date_mode_explicit = 1;
1429        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
1430                revs->date_mode = parse_date_format(optarg);
1431                revs->date_mode_explicit = 1;
1432                return argcount;
1433        } else if (!strcmp(arg, "--log-size")) {
1434                revs->show_log_size = 1;
1435        }
1436        /*
1437         * Grepping the commit log
1438         */
1439        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
1440                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
1441                return argcount;
1442        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
1443                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
1444                return argcount;
1445        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
1446                add_message_grep(revs, optarg);
1447                return argcount;
1448        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
1449                revs->grep_filter.regflags |= REG_EXTENDED;
1450        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
1451                revs->grep_filter.regflags |= REG_ICASE;
1452        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
1453                revs->grep_filter.fixed = 1;
1454        } else if (!strcmp(arg, "--all-match")) {
1455                revs->grep_filter.all_match = 1;
1456        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
1457                if (strcmp(optarg, "none"))
1458                        git_log_output_encoding = xstrdup(optarg);
1459                else
1460                        git_log_output_encoding = "";
1461                return argcount;
1462        } else if (!strcmp(arg, "--reverse")) {
1463                revs->reverse ^= 1;
1464        } else if (!strcmp(arg, "--children")) {
1465                revs->children.name = "children";
1466                revs->limited = 1;
1467        } else {
1468                int opts = diff_opt_parse(&revs->diffopt, argv, argc);
1469                if (!opts)
1470                        unkv[(*unkc)++] = arg;
1471                return opts;
1472        }
1473
1474        return 1;
1475}
1476
1477void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
1478                        const struct option *options,
1479                        const char * const usagestr[])
1480{
1481        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
1482                                    &ctx->cpidx, ctx->out);
1483        if (n <= 0) {
1484                error("unknown option `%s'", ctx->argv[0]);
1485                usage_with_options(usagestr, options);
1486        }
1487        ctx->argv += n;
1488        ctx->argc -= n;
1489}
1490
1491static int for_each_bad_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1492{
1493        return for_each_ref_in_submodule(submodule, "refs/bisect/bad", fn, cb_data);
1494}
1495
1496static int for_each_good_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1497{
1498        return for_each_ref_in_submodule(submodule, "refs/bisect/good", fn, cb_data);
1499}
1500
1501static void append_prune_data(const char ***prune_data, const char **av)
1502{
1503        const char **prune = *prune_data;
1504        int prune_nr;
1505        int prune_alloc;
1506
1507        if (!prune) {
1508                *prune_data = av;
1509                return;
1510        }
1511
1512        /* count existing ones */
1513        for (prune_nr = 0; prune[prune_nr]; prune_nr++)
1514                ;
1515        prune_alloc = prune_nr; /* not really, but we do not know */
1516
1517        while (*av) {
1518                ALLOC_GROW(prune, prune_nr+1, prune_alloc);
1519                prune[prune_nr++] = *av;
1520                av++;
1521        }
1522        if (prune) {
1523                ALLOC_GROW(prune, prune_nr+1, prune_alloc);
1524                prune[prune_nr] = NULL;
1525        }
1526        *prune_data = prune;
1527}
1528
1529/*
1530 * Parse revision information, filling in the "rev_info" structure,
1531 * and removing the used arguments from the argument list.
1532 *
1533 * Returns the number of arguments left that weren't recognized
1534 * (which are also moved to the head of the argument list)
1535 */
1536int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
1537{
1538        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0;
1539        const char **prune_data = NULL;
1540        const char *submodule = NULL;
1541        const char *optarg;
1542        int argcount;
1543
1544        if (opt)
1545                submodule = opt->submodule;
1546
1547        /* First, search for "--" */
1548        seen_dashdash = 0;
1549        for (i = 1; i < argc; i++) {
1550                const char *arg = argv[i];
1551                if (strcmp(arg, "--"))
1552                        continue;
1553                argv[i] = NULL;
1554                argc = i;
1555                if (argv[i + 1])
1556                        prune_data = argv + i + 1;
1557                seen_dashdash = 1;
1558                break;
1559        }
1560
1561        /* Second, deal with arguments and options */
1562        flags = 0;
1563        read_from_stdin = 0;
1564        for (left = i = 1; i < argc; i++) {
1565                const char *arg = argv[i];
1566                if (*arg == '-') {
1567                        int opts;
1568
1569                        if (!strcmp(arg, "--all")) {
1570                                handle_refs(submodule, revs, flags, for_each_ref_submodule);
1571                                handle_refs(submodule, revs, flags, head_ref_submodule);
1572                                continue;
1573                        }
1574                        if (!strcmp(arg, "--branches")) {
1575                                handle_refs(submodule, revs, flags, for_each_branch_ref_submodule);
1576                                continue;
1577                        }
1578                        if (!strcmp(arg, "--bisect")) {
1579                                handle_refs(submodule, revs, flags, for_each_bad_bisect_ref);
1580                                handle_refs(submodule, revs, flags ^ UNINTERESTING, for_each_good_bisect_ref);
1581                                revs->bisect = 1;
1582                                continue;
1583                        }
1584                        if (!strcmp(arg, "--tags")) {
1585                                handle_refs(submodule, revs, flags, for_each_tag_ref_submodule);
1586                                continue;
1587                        }
1588                        if (!strcmp(arg, "--remotes")) {
1589                                handle_refs(submodule, revs, flags, for_each_remote_ref_submodule);
1590                                continue;
1591                        }
1592                        if ((argcount = parse_long_opt("glob", argv + i, &optarg))) {
1593                                struct all_refs_cb cb;
1594                                i += argcount - 1;
1595                                init_all_refs_cb(&cb, revs, flags);
1596                                for_each_glob_ref(handle_one_ref, optarg, &cb);
1597                                continue;
1598                        }
1599                        if (!prefixcmp(arg, "--branches=")) {
1600                                struct all_refs_cb cb;
1601                                init_all_refs_cb(&cb, revs, flags);
1602                                for_each_glob_ref_in(handle_one_ref, arg + 11, "refs/heads/", &cb);
1603                                continue;
1604                        }
1605                        if (!prefixcmp(arg, "--tags=")) {
1606                                struct all_refs_cb cb;
1607                                init_all_refs_cb(&cb, revs, flags);
1608                                for_each_glob_ref_in(handle_one_ref, arg + 7, "refs/tags/", &cb);
1609                                continue;
1610                        }
1611                        if (!prefixcmp(arg, "--remotes=")) {
1612                                struct all_refs_cb cb;
1613                                init_all_refs_cb(&cb, revs, flags);
1614                                for_each_glob_ref_in(handle_one_ref, arg + 10, "refs/remotes/", &cb);
1615                                continue;
1616                        }
1617                        if (!strcmp(arg, "--reflog")) {
1618                                handle_reflog(revs, flags);
1619                                continue;
1620                        }
1621                        if (!strcmp(arg, "--not")) {
1622                                flags ^= UNINTERESTING;
1623                                continue;
1624                        }
1625                        if (!strcmp(arg, "--no-walk")) {
1626                                revs->no_walk = 1;
1627                                continue;
1628                        }
1629                        if (!strcmp(arg, "--do-walk")) {
1630                                revs->no_walk = 0;
1631                                continue;
1632                        }
1633                        if (!strcmp(arg, "--stdin")) {
1634                                if (revs->disable_stdin) {
1635                                        argv[left++] = arg;
1636                                        continue;
1637                                }
1638                                if (read_from_stdin++)
1639                                        die("--stdin given twice?");
1640                                read_revisions_from_stdin(revs, &prune_data);
1641                                continue;
1642                        }
1643
1644                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
1645                        if (opts > 0) {
1646                                i += opts - 1;
1647                                continue;
1648                        }
1649                        if (opts < 0)
1650                                exit(128);
1651                        continue;
1652                }
1653
1654                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1655                        int j;
1656                        if (seen_dashdash || *arg == '^')
1657                                die("bad revision '%s'", arg);
1658
1659                        /* If we didn't have a "--":
1660                         * (1) all filenames must exist;
1661                         * (2) all rev-args must not be interpretable
1662                         *     as a valid filename.
1663                         * but the latter we have checked in the main loop.
1664                         */
1665                        for (j = i; j < argc; j++)
1666                                verify_filename(revs->prefix, argv[j]);
1667
1668                        append_prune_data(&prune_data, argv + i);
1669                        break;
1670                }
1671                else
1672                        got_rev_arg = 1;
1673        }
1674
1675        if (prune_data)
1676                init_pathspec(&revs->prune_data, get_pathspec(revs->prefix, prune_data));
1677
1678        if (revs->def == NULL)
1679                revs->def = opt ? opt->def : NULL;
1680        if (opt && opt->tweak)
1681                opt->tweak(revs, opt);
1682        if (revs->show_merge)
1683                prepare_show_merge(revs);
1684        if (revs->def && !revs->pending.nr && !got_rev_arg) {
1685                unsigned char sha1[20];
1686                struct object *object;
1687                unsigned mode;
1688                if (get_sha1_with_mode(revs->def, sha1, &mode))
1689                        die("bad default revision '%s'", revs->def);
1690                object = get_reference(revs, revs->def, sha1, 0);
1691                add_pending_object_with_mode(revs, object, revs->def, mode);
1692        }
1693
1694        /* Did the user ask for any diff output? Run the diff! */
1695        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
1696                revs->diff = 1;
1697
1698        /* Pickaxe, diff-filter and rename following need diffs */
1699        if (revs->diffopt.pickaxe ||
1700            revs->diffopt.filter ||
1701            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
1702                revs->diff = 1;
1703
1704        if (revs->topo_order)
1705                revs->limited = 1;
1706
1707        if (revs->prune_data.nr) {
1708                diff_tree_setup_paths(revs->prune_data.raw, &revs->pruning);
1709                /* Can't prune commits with rename following: the paths change.. */
1710                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
1711                        revs->prune = 1;
1712                if (!revs->full_diff)
1713                        diff_tree_setup_paths(revs->prune_data.raw, &revs->diffopt);
1714        }
1715        if (revs->combine_merges)
1716                revs->ignore_merges = 0;
1717        revs->diffopt.abbrev = revs->abbrev;
1718        if (diff_setup_done(&revs->diffopt) < 0)
1719                die("diff_setup_done failed");
1720
1721        compile_grep_patterns(&revs->grep_filter);
1722
1723        if (revs->reverse && revs->reflog_info)
1724                die("cannot combine --reverse with --walk-reflogs");
1725        if (revs->rewrite_parents && revs->children.name)
1726                die("cannot combine --parents and --children");
1727
1728        /*
1729         * Limitations on the graph functionality
1730         */
1731        if (revs->reverse && revs->graph)
1732                die("cannot combine --reverse with --graph");
1733
1734        if (revs->reflog_info && revs->graph)
1735                die("cannot combine --walk-reflogs with --graph");
1736
1737        return left;
1738}
1739
1740static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
1741{
1742        struct commit_list *l = xcalloc(1, sizeof(*l));
1743
1744        l->item = child;
1745        l->next = add_decoration(&revs->children, &parent->object, l);
1746}
1747
1748static int remove_duplicate_parents(struct commit *commit)
1749{
1750        struct commit_list **pp, *p;
1751        int surviving_parents;
1752
1753        /* Examine existing parents while marking ones we have seen... */
1754        pp = &commit->parents;
1755        while ((p = *pp) != NULL) {
1756                struct commit *parent = p->item;
1757                if (parent->object.flags & TMP_MARK) {
1758                        *pp = p->next;
1759                        continue;
1760                }
1761                parent->object.flags |= TMP_MARK;
1762                pp = &p->next;
1763        }
1764        /* count them while clearing the temporary mark */
1765        surviving_parents = 0;
1766        for (p = commit->parents; p; p = p->next) {
1767                p->item->object.flags &= ~TMP_MARK;
1768                surviving_parents++;
1769        }
1770        return surviving_parents;
1771}
1772
1773struct merge_simplify_state {
1774        struct commit *simplified;
1775};
1776
1777static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
1778{
1779        struct merge_simplify_state *st;
1780
1781        st = lookup_decoration(&revs->merge_simplification, &commit->object);
1782        if (!st) {
1783                st = xcalloc(1, sizeof(*st));
1784                add_decoration(&revs->merge_simplification, &commit->object, st);
1785        }
1786        return st;
1787}
1788
1789static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
1790{
1791        struct commit_list *p;
1792        struct merge_simplify_state *st, *pst;
1793        int cnt;
1794
1795        st = locate_simplify_state(revs, commit);
1796
1797        /*
1798         * Have we handled this one?
1799         */
1800        if (st->simplified)
1801                return tail;
1802
1803        /*
1804         * An UNINTERESTING commit simplifies to itself, so does a
1805         * root commit.  We do not rewrite parents of such commit
1806         * anyway.
1807         */
1808        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
1809                st->simplified = commit;
1810                return tail;
1811        }
1812
1813        /*
1814         * Do we know what commit all of our parents should be rewritten to?
1815         * Otherwise we are not ready to rewrite this one yet.
1816         */
1817        for (cnt = 0, p = commit->parents; p; p = p->next) {
1818                pst = locate_simplify_state(revs, p->item);
1819                if (!pst->simplified) {
1820                        tail = &commit_list_insert(p->item, tail)->next;
1821                        cnt++;
1822                }
1823        }
1824        if (cnt) {
1825                tail = &commit_list_insert(commit, tail)->next;
1826                return tail;
1827        }
1828
1829        /*
1830         * Rewrite our list of parents.
1831         */
1832        for (p = commit->parents; p; p = p->next) {
1833                pst = locate_simplify_state(revs, p->item);
1834                p->item = pst->simplified;
1835        }
1836        cnt = remove_duplicate_parents(commit);
1837
1838        /*
1839         * It is possible that we are a merge and one side branch
1840         * does not have any commit that touches the given paths;
1841         * in such a case, the immediate parents will be rewritten
1842         * to different commits.
1843         *
1844         *      o----X          X: the commit we are looking at;
1845         *     /    /           o: a commit that touches the paths;
1846         * ---o----'
1847         *
1848         * Further reduce the parents by removing redundant parents.
1849         */
1850        if (1 < cnt) {
1851                struct commit_list *h = reduce_heads(commit->parents);
1852                cnt = commit_list_count(h);
1853                free_commit_list(commit->parents);
1854                commit->parents = h;
1855        }
1856
1857        /*
1858         * A commit simplifies to itself if it is a root, if it is
1859         * UNINTERESTING, if it touches the given paths, or if it is a
1860         * merge and its parents simplifies to more than one commits
1861         * (the first two cases are already handled at the beginning of
1862         * this function).
1863         *
1864         * Otherwise, it simplifies to what its sole parent simplifies to.
1865         */
1866        if (!cnt ||
1867            (commit->object.flags & UNINTERESTING) ||
1868            !(commit->object.flags & TREESAME) ||
1869            (1 < cnt))
1870                st->simplified = commit;
1871        else {
1872                pst = locate_simplify_state(revs, commit->parents->item);
1873                st->simplified = pst->simplified;
1874        }
1875        return tail;
1876}
1877
1878static void simplify_merges(struct rev_info *revs)
1879{
1880        struct commit_list *list;
1881        struct commit_list *yet_to_do, **tail;
1882
1883        if (!revs->topo_order)
1884                sort_in_topological_order(&revs->commits, revs->lifo);
1885        if (!revs->prune)
1886                return;
1887
1888        /* feed the list reversed */
1889        yet_to_do = NULL;
1890        for (list = revs->commits; list; list = list->next)
1891                commit_list_insert(list->item, &yet_to_do);
1892        while (yet_to_do) {
1893                list = yet_to_do;
1894                yet_to_do = NULL;
1895                tail = &yet_to_do;
1896                while (list) {
1897                        struct commit *commit = list->item;
1898                        struct commit_list *next = list->next;
1899                        free(list);
1900                        list = next;
1901                        tail = simplify_one(revs, commit, tail);
1902                }
1903        }
1904
1905        /* clean up the result, removing the simplified ones */
1906        list = revs->commits;
1907        revs->commits = NULL;
1908        tail = &revs->commits;
1909        while (list) {
1910                struct commit *commit = list->item;
1911                struct commit_list *next = list->next;
1912                struct merge_simplify_state *st;
1913                free(list);
1914                list = next;
1915                st = locate_simplify_state(revs, commit);
1916                if (st->simplified == commit)
1917                        tail = &commit_list_insert(commit, tail)->next;
1918        }
1919}
1920
1921static void set_children(struct rev_info *revs)
1922{
1923        struct commit_list *l;
1924        for (l = revs->commits; l; l = l->next) {
1925                struct commit *commit = l->item;
1926                struct commit_list *p;
1927
1928                for (p = commit->parents; p; p = p->next)
1929                        add_child(revs, p->item, commit);
1930        }
1931}
1932
1933int prepare_revision_walk(struct rev_info *revs)
1934{
1935        int nr = revs->pending.nr;
1936        struct object_array_entry *e, *list;
1937
1938        e = list = revs->pending.objects;
1939        revs->pending.nr = 0;
1940        revs->pending.alloc = 0;
1941        revs->pending.objects = NULL;
1942        while (--nr >= 0) {
1943                struct commit *commit = handle_commit(revs, e->item, e->name);
1944                if (commit) {
1945                        if (!(commit->object.flags & SEEN)) {
1946                                commit->object.flags |= SEEN;
1947                                commit_list_insert_by_date(commit, &revs->commits);
1948                        }
1949                }
1950                e++;
1951        }
1952        free(list);
1953
1954        if (revs->no_walk)
1955                return 0;
1956        if (revs->limited)
1957                if (limit_list(revs) < 0)
1958                        return -1;
1959        if (revs->topo_order)
1960                sort_in_topological_order(&revs->commits, revs->lifo);
1961        if (revs->simplify_merges)
1962                simplify_merges(revs);
1963        if (revs->children.name)
1964                set_children(revs);
1965        return 0;
1966}
1967
1968enum rewrite_result {
1969        rewrite_one_ok,
1970        rewrite_one_noparents,
1971        rewrite_one_error
1972};
1973
1974static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
1975{
1976        struct commit_list *cache = NULL;
1977
1978        for (;;) {
1979                struct commit *p = *pp;
1980                if (!revs->limited)
1981                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
1982                                return rewrite_one_error;
1983                if (p->parents && p->parents->next)
1984                        return rewrite_one_ok;
1985                if (p->object.flags & UNINTERESTING)
1986                        return rewrite_one_ok;
1987                if (!(p->object.flags & TREESAME))
1988                        return rewrite_one_ok;
1989                if (!p->parents)
1990                        return rewrite_one_noparents;
1991                *pp = p->parents->item;
1992        }
1993}
1994
1995static int rewrite_parents(struct rev_info *revs, struct commit *commit)
1996{
1997        struct commit_list **pp = &commit->parents;
1998        while (*pp) {
1999                struct commit_list *parent = *pp;
2000                switch (rewrite_one(revs, &parent->item)) {
2001                case rewrite_one_ok:
2002                        break;
2003                case rewrite_one_noparents:
2004                        *pp = parent->next;
2005                        continue;
2006                case rewrite_one_error:
2007                        return -1;
2008                }
2009                pp = &parent->next;
2010        }
2011        remove_duplicate_parents(commit);
2012        return 0;
2013}
2014
2015static int commit_match(struct commit *commit, struct rev_info *opt)
2016{
2017        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2018                return 1;
2019        return grep_buffer(&opt->grep_filter,
2020                           NULL, /* we say nothing, not even filename */
2021                           commit->buffer, strlen(commit->buffer));
2022}
2023
2024static inline int want_ancestry(struct rev_info *revs)
2025{
2026        return (revs->rewrite_parents || revs->children.name);
2027}
2028
2029enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
2030{
2031        if (commit->object.flags & SHOWN)
2032                return commit_ignore;
2033        if (revs->unpacked && has_sha1_pack(commit->object.sha1))
2034                return commit_ignore;
2035        if (revs->show_all)
2036                return commit_show;
2037        if (commit->object.flags & UNINTERESTING)
2038                return commit_ignore;
2039        if (revs->min_age != -1 && (commit->date > revs->min_age))
2040                return commit_ignore;
2041        if (revs->min_parents || (revs->max_parents >= 0)) {
2042                int n = 0;
2043                struct commit_list *p;
2044                for (p = commit->parents; p; p = p->next)
2045                        n++;
2046                if ((n < revs->min_parents) ||
2047                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
2048                        return commit_ignore;
2049        }
2050        if (!commit_match(commit, revs))
2051                return commit_ignore;
2052        if (revs->prune && revs->dense) {
2053                /* Commit without changes? */
2054                if (commit->object.flags & TREESAME) {
2055                        /* drop merges unless we want parenthood */
2056                        if (!want_ancestry(revs))
2057                                return commit_ignore;
2058                        /* non-merge - always ignore it */
2059                        if (!commit->parents || !commit->parents->next)
2060                                return commit_ignore;
2061                }
2062        }
2063        return commit_show;
2064}
2065
2066enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
2067{
2068        enum commit_action action = get_commit_action(revs, commit);
2069
2070        if (action == commit_show &&
2071            !revs->show_all &&
2072            revs->prune && revs->dense && want_ancestry(revs)) {
2073                if (rewrite_parents(revs, commit) < 0)
2074                        return commit_error;
2075        }
2076        return action;
2077}
2078
2079static struct commit *get_revision_1(struct rev_info *revs)
2080{
2081        if (!revs->commits)
2082                return NULL;
2083
2084        do {
2085                struct commit_list *entry = revs->commits;
2086                struct commit *commit = entry->item;
2087
2088                revs->commits = entry->next;
2089                free(entry);
2090
2091                if (revs->reflog_info) {
2092                        fake_reflog_parent(revs->reflog_info, commit);
2093                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
2094                }
2095
2096                /*
2097                 * If we haven't done the list limiting, we need to look at
2098                 * the parents here. We also need to do the date-based limiting
2099                 * that we'd otherwise have done in limit_list().
2100                 */
2101                if (!revs->limited) {
2102                        if (revs->max_age != -1 &&
2103                            (commit->date < revs->max_age))
2104                                continue;
2105                        if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0)
2106                                die("Failed to traverse parents of commit %s",
2107                                    sha1_to_hex(commit->object.sha1));
2108                }
2109
2110                switch (simplify_commit(revs, commit)) {
2111                case commit_ignore:
2112                        continue;
2113                case commit_error:
2114                        die("Failed to simplify parents of commit %s",
2115                            sha1_to_hex(commit->object.sha1));
2116                default:
2117                        return commit;
2118                }
2119        } while (revs->commits);
2120        return NULL;
2121}
2122
2123static void gc_boundary(struct object_array *array)
2124{
2125        unsigned nr = array->nr;
2126        unsigned alloc = array->alloc;
2127        struct object_array_entry *objects = array->objects;
2128
2129        if (alloc <= nr) {
2130                unsigned i, j;
2131                for (i = j = 0; i < nr; i++) {
2132                        if (objects[i].item->flags & SHOWN)
2133                                continue;
2134                        if (i != j)
2135                                objects[j] = objects[i];
2136                        j++;
2137                }
2138                for (i = j; i < nr; i++)
2139                        objects[i].item = NULL;
2140                array->nr = j;
2141        }
2142}
2143
2144static void create_boundary_commit_list(struct rev_info *revs)
2145{
2146        unsigned i;
2147        struct commit *c;
2148        struct object_array *array = &revs->boundary_commits;
2149        struct object_array_entry *objects = array->objects;
2150
2151        /*
2152         * If revs->commits is non-NULL at this point, an error occurred in
2153         * get_revision_1().  Ignore the error and continue printing the
2154         * boundary commits anyway.  (This is what the code has always
2155         * done.)
2156         */
2157        if (revs->commits) {
2158                free_commit_list(revs->commits);
2159                revs->commits = NULL;
2160        }
2161
2162        /*
2163         * Put all of the actual boundary commits from revs->boundary_commits
2164         * into revs->commits
2165         */
2166        for (i = 0; i < array->nr; i++) {
2167                c = (struct commit *)(objects[i].item);
2168                if (!c)
2169                        continue;
2170                if (!(c->object.flags & CHILD_SHOWN))
2171                        continue;
2172                if (c->object.flags & (SHOWN | BOUNDARY))
2173                        continue;
2174                c->object.flags |= BOUNDARY;
2175                commit_list_insert(c, &revs->commits);
2176        }
2177
2178        /*
2179         * If revs->topo_order is set, sort the boundary commits
2180         * in topological order
2181         */
2182        sort_in_topological_order(&revs->commits, revs->lifo);
2183}
2184
2185static struct commit *get_revision_internal(struct rev_info *revs)
2186{
2187        struct commit *c = NULL;
2188        struct commit_list *l;
2189
2190        if (revs->boundary == 2) {
2191                /*
2192                 * All of the normal commits have already been returned,
2193                 * and we are now returning boundary commits.
2194                 * create_boundary_commit_list() has populated
2195                 * revs->commits with the remaining commits to return.
2196                 */
2197                c = pop_commit(&revs->commits);
2198                if (c)
2199                        c->object.flags |= SHOWN;
2200                return c;
2201        }
2202
2203        /*
2204         * Now pick up what they want to give us
2205         */
2206        c = get_revision_1(revs);
2207        if (c) {
2208                while (0 < revs->skip_count) {
2209                        revs->skip_count--;
2210                        c = get_revision_1(revs);
2211                        if (!c)
2212                                break;
2213                }
2214        }
2215
2216        /*
2217         * Check the max_count.
2218         */
2219        switch (revs->max_count) {
2220        case -1:
2221                break;
2222        case 0:
2223                c = NULL;
2224                break;
2225        default:
2226                revs->max_count--;
2227        }
2228
2229        if (c)
2230                c->object.flags |= SHOWN;
2231
2232        if (!revs->boundary) {
2233                return c;
2234        }
2235
2236        if (!c) {
2237                /*
2238                 * get_revision_1() runs out the commits, and
2239                 * we are done computing the boundaries.
2240                 * switch to boundary commits output mode.
2241                 */
2242                revs->boundary = 2;
2243
2244                /*
2245                 * Update revs->commits to contain the list of
2246                 * boundary commits.
2247                 */
2248                create_boundary_commit_list(revs);
2249
2250                return get_revision_internal(revs);
2251        }
2252
2253        /*
2254         * boundary commits are the commits that are parents of the
2255         * ones we got from get_revision_1() but they themselves are
2256         * not returned from get_revision_1().  Before returning
2257         * 'c', we need to mark its parents that they could be boundaries.
2258         */
2259
2260        for (l = c->parents; l; l = l->next) {
2261                struct object *p;
2262                p = &(l->item->object);
2263                if (p->flags & (CHILD_SHOWN | SHOWN))
2264                        continue;
2265                p->flags |= CHILD_SHOWN;
2266                gc_boundary(&revs->boundary_commits);
2267                add_object_array(p, NULL, &revs->boundary_commits);
2268        }
2269
2270        return c;
2271}
2272
2273struct commit *get_revision(struct rev_info *revs)
2274{
2275        struct commit *c;
2276        struct commit_list *reversed;
2277
2278        if (revs->reverse) {
2279                reversed = NULL;
2280                while ((c = get_revision_internal(revs))) {
2281                        commit_list_insert(c, &reversed);
2282                }
2283                revs->commits = reversed;
2284                revs->reverse = 0;
2285                revs->reverse_output_stage = 1;
2286        }
2287
2288        if (revs->reverse_output_stage)
2289                return pop_commit(&revs->commits);
2290
2291        c = get_revision_internal(revs);
2292        if (c && revs->graph)
2293                graph_update(revs->graph, c);
2294        return c;
2295}
2296
2297char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
2298{
2299        if (commit->object.flags & BOUNDARY)
2300                return "-";
2301        else if (commit->object.flags & UNINTERESTING)
2302                return "^";
2303        else if (commit->object.flags & PATCHSAME)
2304                return "=";
2305        else if (!revs || revs->left_right) {
2306                if (commit->object.flags & SYMMETRIC_LEFT)
2307                        return "<";
2308                else
2309                        return ">";
2310        } else if (revs->graph)
2311                return "*";
2312        else if (revs->cherry_mark)
2313                return "+";
2314        return "";
2315}
2316
2317void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
2318{
2319        char *mark = get_revision_mark(revs, commit);
2320        if (!strlen(mark))
2321                return;
2322        fputs(mark, stdout);
2323        putchar(' ');
2324}