revision.con commit rev-list: disable bitmaps when "-n" is used with listing objects (fb85db8)
   1#include "cache.h"
   2#include "tag.h"
   3#include "blob.h"
   4#include "tree.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "refs.h"
   8#include "revision.h"
   9#include "graph.h"
  10#include "grep.h"
  11#include "reflog-walk.h"
  12#include "patch-ids.h"
  13#include "decorate.h"
  14#include "log-tree.h"
  15#include "string-list.h"
  16#include "line-log.h"
  17#include "mailmap.h"
  18#include "commit-slab.h"
  19#include "dir.h"
  20#include "cache-tree.h"
  21
  22volatile show_early_output_fn_t show_early_output;
  23
  24void show_object_with_name(FILE *out, struct object *obj, const char *name)
  25{
  26        const char *p;
  27
  28        fprintf(out, "%s ", sha1_to_hex(obj->sha1));
  29        for (p = name; *p && *p != '\n'; p++)
  30                fputc(*p, out);
  31        fputc('\n', out);
  32}
  33
  34static void mark_blob_uninteresting(struct blob *blob)
  35{
  36        if (!blob)
  37                return;
  38        if (blob->object.flags & UNINTERESTING)
  39                return;
  40        blob->object.flags |= UNINTERESTING;
  41}
  42
  43static void mark_tree_contents_uninteresting(struct tree *tree)
  44{
  45        struct tree_desc desc;
  46        struct name_entry entry;
  47        struct object *obj = &tree->object;
  48
  49        if (!has_sha1_file(obj->sha1))
  50                return;
  51        if (parse_tree(tree) < 0)
  52                die("bad tree %s", sha1_to_hex(obj->sha1));
  53
  54        init_tree_desc(&desc, tree->buffer, tree->size);
  55        while (tree_entry(&desc, &entry)) {
  56                switch (object_type(entry.mode)) {
  57                case OBJ_TREE:
  58                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  59                        break;
  60                case OBJ_BLOB:
  61                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  62                        break;
  63                default:
  64                        /* Subproject commit - not in this repository */
  65                        break;
  66                }
  67        }
  68
  69        /*
  70         * We don't care about the tree any more
  71         * after it has been marked uninteresting.
  72         */
  73        free_tree_buffer(tree);
  74}
  75
  76void mark_tree_uninteresting(struct tree *tree)
  77{
  78        struct object *obj = &tree->object;
  79
  80        if (!tree)
  81                return;
  82        if (obj->flags & UNINTERESTING)
  83                return;
  84        obj->flags |= UNINTERESTING;
  85        mark_tree_contents_uninteresting(tree);
  86}
  87
  88void mark_parents_uninteresting(struct commit *commit)
  89{
  90        struct commit_list *parents = NULL, *l;
  91
  92        for (l = commit->parents; l; l = l->next)
  93                commit_list_insert(l->item, &parents);
  94
  95        while (parents) {
  96                struct commit *commit = parents->item;
  97                l = parents;
  98                parents = parents->next;
  99                free(l);
 100
 101                while (commit) {
 102                        /*
 103                         * A missing commit is ok iff its parent is marked
 104                         * uninteresting.
 105                         *
 106                         * We just mark such a thing parsed, so that when
 107                         * it is popped next time around, we won't be trying
 108                         * to parse it and get an error.
 109                         */
 110                        if (!has_sha1_file(commit->object.sha1))
 111                                commit->object.parsed = 1;
 112
 113                        if (commit->object.flags & UNINTERESTING)
 114                                break;
 115
 116                        commit->object.flags |= UNINTERESTING;
 117
 118                        /*
 119                         * Normally we haven't parsed the parent
 120                         * yet, so we won't have a parent of a parent
 121                         * here. However, it may turn out that we've
 122                         * reached this commit some other way (where it
 123                         * wasn't uninteresting), in which case we need
 124                         * to mark its parents recursively too..
 125                         */
 126                        if (!commit->parents)
 127                                break;
 128
 129                        for (l = commit->parents->next; l; l = l->next)
 130                                commit_list_insert(l->item, &parents);
 131                        commit = commit->parents->item;
 132                }
 133        }
 134}
 135
 136static void add_pending_object_with_path(struct rev_info *revs,
 137                                         struct object *obj,
 138                                         const char *name, unsigned mode,
 139                                         const char *path)
 140{
 141        if (!obj)
 142                return;
 143        if (revs->no_walk && (obj->flags & UNINTERESTING))
 144                revs->no_walk = 0;
 145        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 146                struct strbuf buf = STRBUF_INIT;
 147                int len = interpret_branch_name(name, 0, &buf);
 148                int st;
 149
 150                if (0 < len && name[len] && buf.len)
 151                        strbuf_addstr(&buf, name + len);
 152                st = add_reflog_for_walk(revs->reflog_info,
 153                                         (struct commit *)obj,
 154                                         buf.buf[0] ? buf.buf: name);
 155                strbuf_release(&buf);
 156                if (st)
 157                        return;
 158        }
 159        add_object_array_with_path(obj, name, &revs->pending, mode, path);
 160}
 161
 162static void add_pending_object_with_mode(struct rev_info *revs,
 163                                         struct object *obj,
 164                                         const char *name, unsigned mode)
 165{
 166        add_pending_object_with_path(revs, obj, name, mode, NULL);
 167}
 168
 169void add_pending_object(struct rev_info *revs,
 170                        struct object *obj, const char *name)
 171{
 172        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 173}
 174
 175void add_head_to_pending(struct rev_info *revs)
 176{
 177        unsigned char sha1[20];
 178        struct object *obj;
 179        if (get_sha1("HEAD", sha1))
 180                return;
 181        obj = parse_object(sha1);
 182        if (!obj)
 183                return;
 184        add_pending_object(revs, obj, "HEAD");
 185}
 186
 187static struct object *get_reference(struct rev_info *revs, const char *name,
 188                                    const unsigned char *sha1,
 189                                    unsigned int flags)
 190{
 191        struct object *object;
 192
 193        object = parse_object(sha1);
 194        if (!object) {
 195                if (revs->ignore_missing)
 196                        return object;
 197                die("bad object %s", name);
 198        }
 199        object->flags |= flags;
 200        return object;
 201}
 202
 203void add_pending_sha1(struct rev_info *revs, const char *name,
 204                      const unsigned char *sha1, unsigned int flags)
 205{
 206        struct object *object = get_reference(revs, name, sha1, flags);
 207        add_pending_object(revs, object, name);
 208}
 209
 210static struct commit *handle_commit(struct rev_info *revs,
 211                                    struct object_array_entry *entry)
 212{
 213        struct object *object = entry->item;
 214        const char *name = entry->name;
 215        const char *path = entry->path;
 216        unsigned int mode = entry->mode;
 217        unsigned long flags = object->flags;
 218
 219        /*
 220         * Tag object? Look what it points to..
 221         */
 222        while (object->type == OBJ_TAG) {
 223                struct tag *tag = (struct tag *) object;
 224                if (revs->tag_objects && !(flags & UNINTERESTING))
 225                        add_pending_object(revs, object, tag->tag);
 226                if (!tag->tagged)
 227                        die("bad tag");
 228                object = parse_object(tag->tagged->sha1);
 229                if (!object) {
 230                        if (flags & UNINTERESTING)
 231                                return NULL;
 232                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 233                }
 234                object->flags |= flags;
 235                /*
 236                 * We'll handle the tagged object by looping or dropping
 237                 * through to the non-tag handlers below. Do not
 238                 * propagate data from the tag's pending entry.
 239                 */
 240                name = "";
 241                path = NULL;
 242                mode = 0;
 243        }
 244
 245        /*
 246         * Commit object? Just return it, we'll do all the complex
 247         * reachability crud.
 248         */
 249        if (object->type == OBJ_COMMIT) {
 250                struct commit *commit = (struct commit *)object;
 251                if (parse_commit(commit) < 0)
 252                        die("unable to parse commit %s", name);
 253                if (flags & UNINTERESTING) {
 254                        mark_parents_uninteresting(commit);
 255                        revs->limited = 1;
 256                }
 257                if (revs->show_source && !commit->util)
 258                        commit->util = xstrdup(name);
 259                return commit;
 260        }
 261
 262        /*
 263         * Tree object? Either mark it uninteresting, or add it
 264         * to the list of objects to look at later..
 265         */
 266        if (object->type == OBJ_TREE) {
 267                struct tree *tree = (struct tree *)object;
 268                if (!revs->tree_objects)
 269                        return NULL;
 270                if (flags & UNINTERESTING) {
 271                        mark_tree_contents_uninteresting(tree);
 272                        return NULL;
 273                }
 274                add_pending_object_with_path(revs, object, name, mode, path);
 275                return NULL;
 276        }
 277
 278        /*
 279         * Blob object? You know the drill by now..
 280         */
 281        if (object->type == OBJ_BLOB) {
 282                if (!revs->blob_objects)
 283                        return NULL;
 284                if (flags & UNINTERESTING)
 285                        return NULL;
 286                add_pending_object_with_path(revs, object, name, mode, path);
 287                return NULL;
 288        }
 289        die("%s is unknown object", name);
 290}
 291
 292static int everybody_uninteresting(struct commit_list *orig,
 293                                   struct commit **interesting_cache)
 294{
 295        struct commit_list *list = orig;
 296
 297        if (*interesting_cache) {
 298                struct commit *commit = *interesting_cache;
 299                if (!(commit->object.flags & UNINTERESTING))
 300                        return 0;
 301        }
 302
 303        while (list) {
 304                struct commit *commit = list->item;
 305                list = list->next;
 306                if (commit->object.flags & UNINTERESTING)
 307                        continue;
 308                if (interesting_cache)
 309                        *interesting_cache = commit;
 310                return 0;
 311        }
 312        return 1;
 313}
 314
 315/*
 316 * A definition of "relevant" commit that we can use to simplify limited graphs
 317 * by eliminating side branches.
 318 *
 319 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 320 * in our list), or that is a specified BOTTOM commit. Then after computing
 321 * a limited list, during processing we can generally ignore boundary merges
 322 * coming from outside the graph, (ie from irrelevant parents), and treat
 323 * those merges as if they were single-parent. TREESAME is defined to consider
 324 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 325 * we don't care if we were !TREESAME to non-graph parents.
 326 *
 327 * Treating bottom commits as relevant ensures that a limited graph's
 328 * connection to the actual bottom commit is not viewed as a side branch, but
 329 * treated as part of the graph. For example:
 330 *
 331 *   ....Z...A---X---o---o---B
 332 *        .     /
 333 *         W---Y
 334 *
 335 * When computing "A..B", the A-X connection is at least as important as
 336 * Y-X, despite A being flagged UNINTERESTING.
 337 *
 338 * And when computing --ancestry-path "A..B", the A-X connection is more
 339 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 340 */
 341static inline int relevant_commit(struct commit *commit)
 342{
 343        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 344}
 345
 346/*
 347 * Return a single relevant commit from a parent list. If we are a TREESAME
 348 * commit, and this selects one of our parents, then we can safely simplify to
 349 * that parent.
 350 */
 351static struct commit *one_relevant_parent(const struct rev_info *revs,
 352                                          struct commit_list *orig)
 353{
 354        struct commit_list *list = orig;
 355        struct commit *relevant = NULL;
 356
 357        if (!orig)
 358                return NULL;
 359
 360        /*
 361         * For 1-parent commits, or if first-parent-only, then return that
 362         * first parent (even if not "relevant" by the above definition).
 363         * TREESAME will have been set purely on that parent.
 364         */
 365        if (revs->first_parent_only || !orig->next)
 366                return orig->item;
 367
 368        /*
 369         * For multi-parent commits, identify a sole relevant parent, if any.
 370         * If we have only one relevant parent, then TREESAME will be set purely
 371         * with regard to that parent, and we can simplify accordingly.
 372         *
 373         * If we have more than one relevant parent, or no relevant parents
 374         * (and multiple irrelevant ones), then we can't select a parent here
 375         * and return NULL.
 376         */
 377        while (list) {
 378                struct commit *commit = list->item;
 379                list = list->next;
 380                if (relevant_commit(commit)) {
 381                        if (relevant)
 382                                return NULL;
 383                        relevant = commit;
 384                }
 385        }
 386        return relevant;
 387}
 388
 389/*
 390 * The goal is to get REV_TREE_NEW as the result only if the
 391 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 392 * if the whole diff is removal of old data, and otherwise
 393 * REV_TREE_DIFFERENT (of course if the trees are the same we
 394 * want REV_TREE_SAME).
 395 * That means that once we get to REV_TREE_DIFFERENT, we do not
 396 * have to look any further.
 397 */
 398static int tree_difference = REV_TREE_SAME;
 399
 400static void file_add_remove(struct diff_options *options,
 401                    int addremove, unsigned mode,
 402                    const unsigned char *sha1,
 403                    int sha1_valid,
 404                    const char *fullpath, unsigned dirty_submodule)
 405{
 406        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 407
 408        tree_difference |= diff;
 409        if (tree_difference == REV_TREE_DIFFERENT)
 410                DIFF_OPT_SET(options, HAS_CHANGES);
 411}
 412
 413static void file_change(struct diff_options *options,
 414                 unsigned old_mode, unsigned new_mode,
 415                 const unsigned char *old_sha1,
 416                 const unsigned char *new_sha1,
 417                 int old_sha1_valid, int new_sha1_valid,
 418                 const char *fullpath,
 419                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 420{
 421        tree_difference = REV_TREE_DIFFERENT;
 422        DIFF_OPT_SET(options, HAS_CHANGES);
 423}
 424
 425static int rev_compare_tree(struct rev_info *revs,
 426                            struct commit *parent, struct commit *commit)
 427{
 428        struct tree *t1 = parent->tree;
 429        struct tree *t2 = commit->tree;
 430
 431        if (!t1)
 432                return REV_TREE_NEW;
 433        if (!t2)
 434                return REV_TREE_OLD;
 435
 436        if (revs->simplify_by_decoration) {
 437                /*
 438                 * If we are simplifying by decoration, then the commit
 439                 * is worth showing if it has a tag pointing at it.
 440                 */
 441                if (get_name_decoration(&commit->object))
 442                        return REV_TREE_DIFFERENT;
 443                /*
 444                 * A commit that is not pointed by a tag is uninteresting
 445                 * if we are not limited by path.  This means that you will
 446                 * see the usual "commits that touch the paths" plus any
 447                 * tagged commit by specifying both --simplify-by-decoration
 448                 * and pathspec.
 449                 */
 450                if (!revs->prune_data.nr)
 451                        return REV_TREE_SAME;
 452        }
 453
 454        tree_difference = REV_TREE_SAME;
 455        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 456        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 457                           &revs->pruning) < 0)
 458                return REV_TREE_DIFFERENT;
 459        return tree_difference;
 460}
 461
 462static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 463{
 464        int retval;
 465        struct tree *t1 = commit->tree;
 466
 467        if (!t1)
 468                return 0;
 469
 470        tree_difference = REV_TREE_SAME;
 471        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 472        retval = diff_tree_sha1(NULL, t1->object.sha1, "", &revs->pruning);
 473
 474        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 475}
 476
 477struct treesame_state {
 478        unsigned int nparents;
 479        unsigned char treesame[FLEX_ARRAY];
 480};
 481
 482static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 483{
 484        unsigned n = commit_list_count(commit->parents);
 485        struct treesame_state *st = xcalloc(1, sizeof(*st) + n);
 486        st->nparents = n;
 487        add_decoration(&revs->treesame, &commit->object, st);
 488        return st;
 489}
 490
 491/*
 492 * Must be called immediately after removing the nth_parent from a commit's
 493 * parent list, if we are maintaining the per-parent treesame[] decoration.
 494 * This does not recalculate the master TREESAME flag - update_treesame()
 495 * should be called to update it after a sequence of treesame[] modifications
 496 * that may have affected it.
 497 */
 498static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 499{
 500        struct treesame_state *st;
 501        int old_same;
 502
 503        if (!commit->parents) {
 504                /*
 505                 * Have just removed the only parent from a non-merge.
 506                 * Different handling, as we lack decoration.
 507                 */
 508                if (nth_parent != 0)
 509                        die("compact_treesame %u", nth_parent);
 510                old_same = !!(commit->object.flags & TREESAME);
 511                if (rev_same_tree_as_empty(revs, commit))
 512                        commit->object.flags |= TREESAME;
 513                else
 514                        commit->object.flags &= ~TREESAME;
 515                return old_same;
 516        }
 517
 518        st = lookup_decoration(&revs->treesame, &commit->object);
 519        if (!st || nth_parent >= st->nparents)
 520                die("compact_treesame %u", nth_parent);
 521
 522        old_same = st->treesame[nth_parent];
 523        memmove(st->treesame + nth_parent,
 524                st->treesame + nth_parent + 1,
 525                st->nparents - nth_parent - 1);
 526
 527        /*
 528         * If we've just become a non-merge commit, update TREESAME
 529         * immediately, and remove the no-longer-needed decoration.
 530         * If still a merge, defer update until update_treesame().
 531         */
 532        if (--st->nparents == 1) {
 533                if (commit->parents->next)
 534                        die("compact_treesame parents mismatch");
 535                if (st->treesame[0] && revs->dense)
 536                        commit->object.flags |= TREESAME;
 537                else
 538                        commit->object.flags &= ~TREESAME;
 539                free(add_decoration(&revs->treesame, &commit->object, NULL));
 540        }
 541
 542        return old_same;
 543}
 544
 545static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 546{
 547        if (commit->parents && commit->parents->next) {
 548                unsigned n;
 549                struct treesame_state *st;
 550                struct commit_list *p;
 551                unsigned relevant_parents;
 552                unsigned relevant_change, irrelevant_change;
 553
 554                st = lookup_decoration(&revs->treesame, &commit->object);
 555                if (!st)
 556                        die("update_treesame %s", sha1_to_hex(commit->object.sha1));
 557                relevant_parents = 0;
 558                relevant_change = irrelevant_change = 0;
 559                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 560                        if (relevant_commit(p->item)) {
 561                                relevant_change |= !st->treesame[n];
 562                                relevant_parents++;
 563                        } else
 564                                irrelevant_change |= !st->treesame[n];
 565                }
 566                if (relevant_parents ? relevant_change : irrelevant_change)
 567                        commit->object.flags &= ~TREESAME;
 568                else
 569                        commit->object.flags |= TREESAME;
 570        }
 571
 572        return commit->object.flags & TREESAME;
 573}
 574
 575static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 576{
 577        /*
 578         * TREESAME is irrelevant unless prune && dense;
 579         * if simplify_history is set, we can't have a mixture of TREESAME and
 580         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 581         *    decoration anyway);
 582         * if first_parent_only is set, then the TREESAME flag is locked
 583         *    against the first parent (and again we lack treesame[] decoration).
 584         */
 585        return revs->prune && revs->dense &&
 586               !revs->simplify_history &&
 587               !revs->first_parent_only;
 588}
 589
 590static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 591{
 592        struct commit_list **pp, *parent;
 593        struct treesame_state *ts = NULL;
 594        int relevant_change = 0, irrelevant_change = 0;
 595        int relevant_parents, nth_parent;
 596
 597        /*
 598         * If we don't do pruning, everything is interesting
 599         */
 600        if (!revs->prune)
 601                return;
 602
 603        if (!commit->tree)
 604                return;
 605
 606        if (!commit->parents) {
 607                if (rev_same_tree_as_empty(revs, commit))
 608                        commit->object.flags |= TREESAME;
 609                return;
 610        }
 611
 612        /*
 613         * Normal non-merge commit? If we don't want to make the
 614         * history dense, we consider it always to be a change..
 615         */
 616        if (!revs->dense && !commit->parents->next)
 617                return;
 618
 619        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 620             (parent = *pp) != NULL;
 621             pp = &parent->next, nth_parent++) {
 622                struct commit *p = parent->item;
 623                if (relevant_commit(p))
 624                        relevant_parents++;
 625
 626                if (nth_parent == 1) {
 627                        /*
 628                         * This our second loop iteration - so we now know
 629                         * we're dealing with a merge.
 630                         *
 631                         * Do not compare with later parents when we care only about
 632                         * the first parent chain, in order to avoid derailing the
 633                         * traversal to follow a side branch that brought everything
 634                         * in the path we are limited to by the pathspec.
 635                         */
 636                        if (revs->first_parent_only)
 637                                break;
 638                        /*
 639                         * If this will remain a potentially-simplifiable
 640                         * merge, remember per-parent treesame if needed.
 641                         * Initialise the array with the comparison from our
 642                         * first iteration.
 643                         */
 644                        if (revs->treesame.name &&
 645                            !revs->simplify_history &&
 646                            !(commit->object.flags & UNINTERESTING)) {
 647                                ts = initialise_treesame(revs, commit);
 648                                if (!(irrelevant_change || relevant_change))
 649                                        ts->treesame[0] = 1;
 650                        }
 651                }
 652                if (parse_commit(p) < 0)
 653                        die("cannot simplify commit %s (because of %s)",
 654                            sha1_to_hex(commit->object.sha1),
 655                            sha1_to_hex(p->object.sha1));
 656                switch (rev_compare_tree(revs, p, commit)) {
 657                case REV_TREE_SAME:
 658                        if (!revs->simplify_history || !relevant_commit(p)) {
 659                                /* Even if a merge with an uninteresting
 660                                 * side branch brought the entire change
 661                                 * we are interested in, we do not want
 662                                 * to lose the other branches of this
 663                                 * merge, so we just keep going.
 664                                 */
 665                                if (ts)
 666                                        ts->treesame[nth_parent] = 1;
 667                                continue;
 668                        }
 669                        parent->next = NULL;
 670                        commit->parents = parent;
 671                        commit->object.flags |= TREESAME;
 672                        return;
 673
 674                case REV_TREE_NEW:
 675                        if (revs->remove_empty_trees &&
 676                            rev_same_tree_as_empty(revs, p)) {
 677                                /* We are adding all the specified
 678                                 * paths from this parent, so the
 679                                 * history beyond this parent is not
 680                                 * interesting.  Remove its parents
 681                                 * (they are grandparents for us).
 682                                 * IOW, we pretend this parent is a
 683                                 * "root" commit.
 684                                 */
 685                                if (parse_commit(p) < 0)
 686                                        die("cannot simplify commit %s (invalid %s)",
 687                                            sha1_to_hex(commit->object.sha1),
 688                                            sha1_to_hex(p->object.sha1));
 689                                p->parents = NULL;
 690                        }
 691                /* fallthrough */
 692                case REV_TREE_OLD:
 693                case REV_TREE_DIFFERENT:
 694                        if (relevant_commit(p))
 695                                relevant_change = 1;
 696                        else
 697                                irrelevant_change = 1;
 698                        continue;
 699                }
 700                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 701        }
 702
 703        /*
 704         * TREESAME is straightforward for single-parent commits. For merge
 705         * commits, it is most useful to define it so that "irrelevant"
 706         * parents cannot make us !TREESAME - if we have any relevant
 707         * parents, then we only consider TREESAMEness with respect to them,
 708         * allowing irrelevant merges from uninteresting branches to be
 709         * simplified away. Only if we have only irrelevant parents do we
 710         * base TREESAME on them. Note that this logic is replicated in
 711         * update_treesame, which should be kept in sync.
 712         */
 713        if (relevant_parents ? !relevant_change : !irrelevant_change)
 714                commit->object.flags |= TREESAME;
 715}
 716
 717static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 718                    struct commit_list *cached_base, struct commit_list **cache)
 719{
 720        struct commit_list *new_entry;
 721
 722        if (cached_base && p->date < cached_base->item->date)
 723                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 724        else
 725                new_entry = commit_list_insert_by_date(p, head);
 726
 727        if (cache && (!*cache || p->date < (*cache)->item->date))
 728                *cache = new_entry;
 729}
 730
 731static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 732                    struct commit_list **list, struct commit_list **cache_ptr)
 733{
 734        struct commit_list *parent = commit->parents;
 735        unsigned left_flag;
 736        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 737
 738        if (commit->object.flags & ADDED)
 739                return 0;
 740        commit->object.flags |= ADDED;
 741
 742        if (revs->include_check &&
 743            !revs->include_check(commit, revs->include_check_data))
 744                return 0;
 745
 746        /*
 747         * If the commit is uninteresting, don't try to
 748         * prune parents - we want the maximal uninteresting
 749         * set.
 750         *
 751         * Normally we haven't parsed the parent
 752         * yet, so we won't have a parent of a parent
 753         * here. However, it may turn out that we've
 754         * reached this commit some other way (where it
 755         * wasn't uninteresting), in which case we need
 756         * to mark its parents recursively too..
 757         */
 758        if (commit->object.flags & UNINTERESTING) {
 759                while (parent) {
 760                        struct commit *p = parent->item;
 761                        parent = parent->next;
 762                        if (p)
 763                                p->object.flags |= UNINTERESTING;
 764                        if (parse_commit_gently(p, 1) < 0)
 765                                continue;
 766                        if (p->parents)
 767                                mark_parents_uninteresting(p);
 768                        if (p->object.flags & SEEN)
 769                                continue;
 770                        p->object.flags |= SEEN;
 771                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 772                }
 773                return 0;
 774        }
 775
 776        /*
 777         * Ok, the commit wasn't uninteresting. Try to
 778         * simplify the commit history and find the parent
 779         * that has no differences in the path set if one exists.
 780         */
 781        try_to_simplify_commit(revs, commit);
 782
 783        if (revs->no_walk)
 784                return 0;
 785
 786        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 787
 788        for (parent = commit->parents; parent; parent = parent->next) {
 789                struct commit *p = parent->item;
 790
 791                if (parse_commit_gently(p, revs->ignore_missing_links) < 0)
 792                        return -1;
 793                if (revs->show_source && !p->util)
 794                        p->util = commit->util;
 795                p->object.flags |= left_flag;
 796                if (!(p->object.flags & SEEN)) {
 797                        p->object.flags |= SEEN;
 798                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 799                }
 800                if (revs->first_parent_only)
 801                        break;
 802        }
 803        return 0;
 804}
 805
 806static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 807{
 808        struct commit_list *p;
 809        int left_count = 0, right_count = 0;
 810        int left_first;
 811        struct patch_ids ids;
 812        unsigned cherry_flag;
 813
 814        /* First count the commits on the left and on the right */
 815        for (p = list; p; p = p->next) {
 816                struct commit *commit = p->item;
 817                unsigned flags = commit->object.flags;
 818                if (flags & BOUNDARY)
 819                        ;
 820                else if (flags & SYMMETRIC_LEFT)
 821                        left_count++;
 822                else
 823                        right_count++;
 824        }
 825
 826        if (!left_count || !right_count)
 827                return;
 828
 829        left_first = left_count < right_count;
 830        init_patch_ids(&ids);
 831        ids.diffopts.pathspec = revs->diffopt.pathspec;
 832
 833        /* Compute patch-ids for one side */
 834        for (p = list; p; p = p->next) {
 835                struct commit *commit = p->item;
 836                unsigned flags = commit->object.flags;
 837
 838                if (flags & BOUNDARY)
 839                        continue;
 840                /*
 841                 * If we have fewer left, left_first is set and we omit
 842                 * commits on the right branch in this loop.  If we have
 843                 * fewer right, we skip the left ones.
 844                 */
 845                if (left_first != !!(flags & SYMMETRIC_LEFT))
 846                        continue;
 847                commit->util = add_commit_patch_id(commit, &ids);
 848        }
 849
 850        /* either cherry_mark or cherry_pick are true */
 851        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 852
 853        /* Check the other side */
 854        for (p = list; p; p = p->next) {
 855                struct commit *commit = p->item;
 856                struct patch_id *id;
 857                unsigned flags = commit->object.flags;
 858
 859                if (flags & BOUNDARY)
 860                        continue;
 861                /*
 862                 * If we have fewer left, left_first is set and we omit
 863                 * commits on the left branch in this loop.
 864                 */
 865                if (left_first == !!(flags & SYMMETRIC_LEFT))
 866                        continue;
 867
 868                /*
 869                 * Have we seen the same patch id?
 870                 */
 871                id = has_commit_patch_id(commit, &ids);
 872                if (!id)
 873                        continue;
 874                id->seen = 1;
 875                commit->object.flags |= cherry_flag;
 876        }
 877
 878        /* Now check the original side for seen ones */
 879        for (p = list; p; p = p->next) {
 880                struct commit *commit = p->item;
 881                struct patch_id *ent;
 882
 883                ent = commit->util;
 884                if (!ent)
 885                        continue;
 886                if (ent->seen)
 887                        commit->object.flags |= cherry_flag;
 888                commit->util = NULL;
 889        }
 890
 891        free_patch_ids(&ids);
 892}
 893
 894/* How many extra uninteresting commits we want to see.. */
 895#define SLOP 5
 896
 897static int still_interesting(struct commit_list *src, unsigned long date, int slop,
 898                             struct commit **interesting_cache)
 899{
 900        /*
 901         * No source list at all? We're definitely done..
 902         */
 903        if (!src)
 904                return 0;
 905
 906        /*
 907         * Does the destination list contain entries with a date
 908         * before the source list? Definitely _not_ done.
 909         */
 910        if (date <= src->item->date)
 911                return SLOP;
 912
 913        /*
 914         * Does the source list still have interesting commits in
 915         * it? Definitely not done..
 916         */
 917        if (!everybody_uninteresting(src, interesting_cache))
 918                return SLOP;
 919
 920        /* Ok, we're closing in.. */
 921        return slop-1;
 922}
 923
 924/*
 925 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 926 * of B but not ancestors of A but further limits the result to those
 927 * that are descendants of A.  This takes the list of bottom commits and
 928 * the result of "A..B" without --ancestry-path, and limits the latter
 929 * further to the ones that can reach one of the commits in "bottom".
 930 */
 931static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 932{
 933        struct commit_list *p;
 934        struct commit_list *rlist = NULL;
 935        int made_progress;
 936
 937        /*
 938         * Reverse the list so that it will be likely that we would
 939         * process parents before children.
 940         */
 941        for (p = list; p; p = p->next)
 942                commit_list_insert(p->item, &rlist);
 943
 944        for (p = bottom; p; p = p->next)
 945                p->item->object.flags |= TMP_MARK;
 946
 947        /*
 948         * Mark the ones that can reach bottom commits in "list",
 949         * in a bottom-up fashion.
 950         */
 951        do {
 952                made_progress = 0;
 953                for (p = rlist; p; p = p->next) {
 954                        struct commit *c = p->item;
 955                        struct commit_list *parents;
 956                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 957                                continue;
 958                        for (parents = c->parents;
 959                             parents;
 960                             parents = parents->next) {
 961                                if (!(parents->item->object.flags & TMP_MARK))
 962                                        continue;
 963                                c->object.flags |= TMP_MARK;
 964                                made_progress = 1;
 965                                break;
 966                        }
 967                }
 968        } while (made_progress);
 969
 970        /*
 971         * NEEDSWORK: decide if we want to remove parents that are
 972         * not marked with TMP_MARK from commit->parents for commits
 973         * in the resulting list.  We may not want to do that, though.
 974         */
 975
 976        /*
 977         * The ones that are not marked with TMP_MARK are uninteresting
 978         */
 979        for (p = list; p; p = p->next) {
 980                struct commit *c = p->item;
 981                if (c->object.flags & TMP_MARK)
 982                        continue;
 983                c->object.flags |= UNINTERESTING;
 984        }
 985
 986        /* We are done with the TMP_MARK */
 987        for (p = list; p; p = p->next)
 988                p->item->object.flags &= ~TMP_MARK;
 989        for (p = bottom; p; p = p->next)
 990                p->item->object.flags &= ~TMP_MARK;
 991        free_commit_list(rlist);
 992}
 993
 994/*
 995 * Before walking the history, keep the set of "negative" refs the
 996 * caller has asked to exclude.
 997 *
 998 * This is used to compute "rev-list --ancestry-path A..B", as we need
 999 * to filter the result of "A..B" further to the ones that can actually
1000 * reach A.
1001 */
1002static struct commit_list *collect_bottom_commits(struct commit_list *list)
1003{
1004        struct commit_list *elem, *bottom = NULL;
1005        for (elem = list; elem; elem = elem->next)
1006                if (elem->item->object.flags & BOTTOM)
1007                        commit_list_insert(elem->item, &bottom);
1008        return bottom;
1009}
1010
1011/* Assumes either left_only or right_only is set */
1012static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1013{
1014        struct commit_list *p;
1015
1016        for (p = list; p; p = p->next) {
1017                struct commit *commit = p->item;
1018
1019                if (revs->right_only) {
1020                        if (commit->object.flags & SYMMETRIC_LEFT)
1021                                commit->object.flags |= SHOWN;
1022                } else  /* revs->left_only is set */
1023                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1024                                commit->object.flags |= SHOWN;
1025        }
1026}
1027
1028static int limit_list(struct rev_info *revs)
1029{
1030        int slop = SLOP;
1031        unsigned long date = ~0ul;
1032        struct commit_list *list = revs->commits;
1033        struct commit_list *newlist = NULL;
1034        struct commit_list **p = &newlist;
1035        struct commit_list *bottom = NULL;
1036        struct commit *interesting_cache = NULL;
1037
1038        if (revs->ancestry_path) {
1039                bottom = collect_bottom_commits(list);
1040                if (!bottom)
1041                        die("--ancestry-path given but there are no bottom commits");
1042        }
1043
1044        while (list) {
1045                struct commit_list *entry = list;
1046                struct commit *commit = list->item;
1047                struct object *obj = &commit->object;
1048                show_early_output_fn_t show;
1049
1050                list = list->next;
1051                free(entry);
1052
1053                if (commit == interesting_cache)
1054                        interesting_cache = NULL;
1055
1056                if (revs->max_age != -1 && (commit->date < revs->max_age))
1057                        obj->flags |= UNINTERESTING;
1058                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1059                        return -1;
1060                if (obj->flags & UNINTERESTING) {
1061                        mark_parents_uninteresting(commit);
1062                        if (revs->show_all)
1063                                p = &commit_list_insert(commit, p)->next;
1064                        slop = still_interesting(list, date, slop, &interesting_cache);
1065                        if (slop)
1066                                continue;
1067                        /* If showing all, add the whole pending list to the end */
1068                        if (revs->show_all)
1069                                *p = list;
1070                        break;
1071                }
1072                if (revs->min_age != -1 && (commit->date > revs->min_age))
1073                        continue;
1074                date = commit->date;
1075                p = &commit_list_insert(commit, p)->next;
1076
1077                show = show_early_output;
1078                if (!show)
1079                        continue;
1080
1081                show(revs, newlist);
1082                show_early_output = NULL;
1083        }
1084        if (revs->cherry_pick || revs->cherry_mark)
1085                cherry_pick_list(newlist, revs);
1086
1087        if (revs->left_only || revs->right_only)
1088                limit_left_right(newlist, revs);
1089
1090        if (bottom) {
1091                limit_to_ancestry(bottom, newlist);
1092                free_commit_list(bottom);
1093        }
1094
1095        /*
1096         * Check if any commits have become TREESAME by some of their parents
1097         * becoming UNINTERESTING.
1098         */
1099        if (limiting_can_increase_treesame(revs))
1100                for (list = newlist; list; list = list->next) {
1101                        struct commit *c = list->item;
1102                        if (c->object.flags & (UNINTERESTING | TREESAME))
1103                                continue;
1104                        update_treesame(revs, c);
1105                }
1106
1107        revs->commits = newlist;
1108        return 0;
1109}
1110
1111/*
1112 * Add an entry to refs->cmdline with the specified information.
1113 * *name is copied.
1114 */
1115static void add_rev_cmdline(struct rev_info *revs,
1116                            struct object *item,
1117                            const char *name,
1118                            int whence,
1119                            unsigned flags)
1120{
1121        struct rev_cmdline_info *info = &revs->cmdline;
1122        int nr = info->nr;
1123
1124        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1125        info->rev[nr].item = item;
1126        info->rev[nr].name = xstrdup(name);
1127        info->rev[nr].whence = whence;
1128        info->rev[nr].flags = flags;
1129        info->nr++;
1130}
1131
1132static void add_rev_cmdline_list(struct rev_info *revs,
1133                                 struct commit_list *commit_list,
1134                                 int whence,
1135                                 unsigned flags)
1136{
1137        while (commit_list) {
1138                struct object *object = &commit_list->item->object;
1139                add_rev_cmdline(revs, object, sha1_to_hex(object->sha1),
1140                                whence, flags);
1141                commit_list = commit_list->next;
1142        }
1143}
1144
1145struct all_refs_cb {
1146        int all_flags;
1147        int warned_bad_reflog;
1148        struct rev_info *all_revs;
1149        const char *name_for_errormsg;
1150};
1151
1152int ref_excluded(struct string_list *ref_excludes, const char *path)
1153{
1154        struct string_list_item *item;
1155
1156        if (!ref_excludes)
1157                return 0;
1158        for_each_string_list_item(item, ref_excludes) {
1159                if (!wildmatch(item->string, path, 0, NULL))
1160                        return 1;
1161        }
1162        return 0;
1163}
1164
1165static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1166{
1167        struct all_refs_cb *cb = cb_data;
1168        struct object *object;
1169
1170        if (ref_excluded(cb->all_revs->ref_excludes, path))
1171            return 0;
1172
1173        object = get_reference(cb->all_revs, path, sha1, cb->all_flags);
1174        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1175        add_pending_sha1(cb->all_revs, path, sha1, cb->all_flags);
1176        return 0;
1177}
1178
1179static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1180        unsigned flags)
1181{
1182        cb->all_revs = revs;
1183        cb->all_flags = flags;
1184}
1185
1186void clear_ref_exclusion(struct string_list **ref_excludes_p)
1187{
1188        if (*ref_excludes_p) {
1189                string_list_clear(*ref_excludes_p, 0);
1190                free(*ref_excludes_p);
1191        }
1192        *ref_excludes_p = NULL;
1193}
1194
1195void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1196{
1197        if (!*ref_excludes_p) {
1198                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1199                (*ref_excludes_p)->strdup_strings = 1;
1200        }
1201        string_list_append(*ref_excludes_p, exclude);
1202}
1203
1204static void handle_refs(const char *submodule, struct rev_info *revs, unsigned flags,
1205                int (*for_each)(const char *, each_ref_fn, void *))
1206{
1207        struct all_refs_cb cb;
1208        init_all_refs_cb(&cb, revs, flags);
1209        for_each(submodule, handle_one_ref, &cb);
1210}
1211
1212static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
1213{
1214        struct all_refs_cb *cb = cb_data;
1215        if (!is_null_sha1(sha1)) {
1216                struct object *o = parse_object(sha1);
1217                if (o) {
1218                        o->flags |= cb->all_flags;
1219                        /* ??? CMDLINEFLAGS ??? */
1220                        add_pending_object(cb->all_revs, o, "");
1221                }
1222                else if (!cb->warned_bad_reflog) {
1223                        warning("reflog of '%s' references pruned commits",
1224                                cb->name_for_errormsg);
1225                        cb->warned_bad_reflog = 1;
1226                }
1227        }
1228}
1229
1230static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
1231                const char *email, unsigned long timestamp, int tz,
1232                const char *message, void *cb_data)
1233{
1234        handle_one_reflog_commit(osha1, cb_data);
1235        handle_one_reflog_commit(nsha1, cb_data);
1236        return 0;
1237}
1238
1239static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1240{
1241        struct all_refs_cb *cb = cb_data;
1242        cb->warned_bad_reflog = 0;
1243        cb->name_for_errormsg = path;
1244        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
1245        return 0;
1246}
1247
1248void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1249{
1250        struct all_refs_cb cb;
1251        cb.all_revs = revs;
1252        cb.all_flags = flags;
1253        for_each_reflog(handle_one_reflog, &cb);
1254}
1255
1256static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1257                           struct strbuf *path)
1258{
1259        size_t baselen = path->len;
1260        int i;
1261
1262        if (it->entry_count >= 0) {
1263                struct tree *tree = lookup_tree(it->sha1);
1264                add_pending_object_with_path(revs, &tree->object, "",
1265                                             040000, path->buf);
1266        }
1267
1268        for (i = 0; i < it->subtree_nr; i++) {
1269                struct cache_tree_sub *sub = it->down[i];
1270                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1271                add_cache_tree(sub->cache_tree, revs, path);
1272                strbuf_setlen(path, baselen);
1273        }
1274
1275}
1276
1277void add_index_objects_to_pending(struct rev_info *revs, unsigned flags)
1278{
1279        int i;
1280
1281        read_cache();
1282        for (i = 0; i < active_nr; i++) {
1283                struct cache_entry *ce = active_cache[i];
1284                struct blob *blob;
1285
1286                if (S_ISGITLINK(ce->ce_mode))
1287                        continue;
1288
1289                blob = lookup_blob(ce->sha1);
1290                if (!blob)
1291                        die("unable to add index blob to traversal");
1292                add_pending_object_with_path(revs, &blob->object, "",
1293                                             ce->ce_mode, ce->name);
1294        }
1295
1296        if (active_cache_tree) {
1297                struct strbuf path = STRBUF_INIT;
1298                add_cache_tree(active_cache_tree, revs, &path);
1299                strbuf_release(&path);
1300        }
1301}
1302
1303static int add_parents_only(struct rev_info *revs, const char *arg_, int flags)
1304{
1305        unsigned char sha1[20];
1306        struct object *it;
1307        struct commit *commit;
1308        struct commit_list *parents;
1309        const char *arg = arg_;
1310
1311        if (*arg == '^') {
1312                flags ^= UNINTERESTING | BOTTOM;
1313                arg++;
1314        }
1315        if (get_sha1_committish(arg, sha1))
1316                return 0;
1317        while (1) {
1318                it = get_reference(revs, arg, sha1, 0);
1319                if (!it && revs->ignore_missing)
1320                        return 0;
1321                if (it->type != OBJ_TAG)
1322                        break;
1323                if (!((struct tag*)it)->tagged)
1324                        return 0;
1325                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
1326        }
1327        if (it->type != OBJ_COMMIT)
1328                return 0;
1329        commit = (struct commit *)it;
1330        for (parents = commit->parents; parents; parents = parents->next) {
1331                it = &parents->item->object;
1332                it->flags |= flags;
1333                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1334                add_pending_object(revs, it, arg);
1335        }
1336        return 1;
1337}
1338
1339void init_revisions(struct rev_info *revs, const char *prefix)
1340{
1341        memset(revs, 0, sizeof(*revs));
1342
1343        revs->abbrev = DEFAULT_ABBREV;
1344        revs->ignore_merges = 1;
1345        revs->simplify_history = 1;
1346        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
1347        DIFF_OPT_SET(&revs->pruning, QUICK);
1348        revs->pruning.add_remove = file_add_remove;
1349        revs->pruning.change = file_change;
1350        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1351        revs->dense = 1;
1352        revs->prefix = prefix;
1353        revs->max_age = -1;
1354        revs->min_age = -1;
1355        revs->skip_count = -1;
1356        revs->max_count = -1;
1357        revs->max_parents = -1;
1358
1359        revs->commit_format = CMIT_FMT_DEFAULT;
1360
1361        init_grep_defaults();
1362        grep_init(&revs->grep_filter, prefix);
1363        revs->grep_filter.status_only = 1;
1364        revs->grep_filter.regflags = REG_NEWLINE;
1365
1366        diff_setup(&revs->diffopt);
1367        if (prefix && !revs->diffopt.prefix) {
1368                revs->diffopt.prefix = prefix;
1369                revs->diffopt.prefix_length = strlen(prefix);
1370        }
1371
1372        revs->notes_opt.use_default_notes = -1;
1373}
1374
1375static void add_pending_commit_list(struct rev_info *revs,
1376                                    struct commit_list *commit_list,
1377                                    unsigned int flags)
1378{
1379        while (commit_list) {
1380                struct object *object = &commit_list->item->object;
1381                object->flags |= flags;
1382                add_pending_object(revs, object, sha1_to_hex(object->sha1));
1383                commit_list = commit_list->next;
1384        }
1385}
1386
1387static void prepare_show_merge(struct rev_info *revs)
1388{
1389        struct commit_list *bases;
1390        struct commit *head, *other;
1391        unsigned char sha1[20];
1392        const char **prune = NULL;
1393        int i, prune_num = 1; /* counting terminating NULL */
1394
1395        if (get_sha1("HEAD", sha1))
1396                die("--merge without HEAD?");
1397        head = lookup_commit_or_die(sha1, "HEAD");
1398        if (get_sha1("MERGE_HEAD", sha1))
1399                die("--merge without MERGE_HEAD?");
1400        other = lookup_commit_or_die(sha1, "MERGE_HEAD");
1401        add_pending_object(revs, &head->object, "HEAD");
1402        add_pending_object(revs, &other->object, "MERGE_HEAD");
1403        bases = get_merge_bases(head, other);
1404        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1405        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1406        free_commit_list(bases);
1407        head->object.flags |= SYMMETRIC_LEFT;
1408
1409        if (!active_nr)
1410                read_cache();
1411        for (i = 0; i < active_nr; i++) {
1412                const struct cache_entry *ce = active_cache[i];
1413                if (!ce_stage(ce))
1414                        continue;
1415                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1416                        prune_num++;
1417                        REALLOC_ARRAY(prune, prune_num);
1418                        prune[prune_num-2] = ce->name;
1419                        prune[prune_num-1] = NULL;
1420                }
1421                while ((i+1 < active_nr) &&
1422                       ce_same_name(ce, active_cache[i+1]))
1423                        i++;
1424        }
1425        free_pathspec(&revs->prune_data);
1426        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1427                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1428        revs->limited = 1;
1429}
1430
1431int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1432{
1433        struct object_context oc;
1434        char *dotdot;
1435        struct object *object;
1436        unsigned char sha1[20];
1437        int local_flags;
1438        const char *arg = arg_;
1439        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1440        unsigned get_sha1_flags = 0;
1441
1442        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1443
1444        dotdot = strstr(arg, "..");
1445        if (dotdot) {
1446                unsigned char from_sha1[20];
1447                const char *next = dotdot + 2;
1448                const char *this = arg;
1449                int symmetric = *next == '.';
1450                unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1451                static const char head_by_default[] = "HEAD";
1452                unsigned int a_flags;
1453
1454                *dotdot = 0;
1455                next += symmetric;
1456
1457                if (!*next)
1458                        next = head_by_default;
1459                if (dotdot == arg)
1460                        this = head_by_default;
1461                if (this == head_by_default && next == head_by_default &&
1462                    !symmetric) {
1463                        /*
1464                         * Just ".."?  That is not a range but the
1465                         * pathspec for the parent directory.
1466                         */
1467                        if (!cant_be_filename) {
1468                                *dotdot = '.';
1469                                return -1;
1470                        }
1471                }
1472                if (!get_sha1_committish(this, from_sha1) &&
1473                    !get_sha1_committish(next, sha1)) {
1474                        struct object *a_obj, *b_obj;
1475
1476                        if (!cant_be_filename) {
1477                                *dotdot = '.';
1478                                verify_non_filename(revs->prefix, arg);
1479                        }
1480
1481                        a_obj = parse_object(from_sha1);
1482                        b_obj = parse_object(sha1);
1483                        if (!a_obj || !b_obj) {
1484                        missing:
1485                                if (revs->ignore_missing)
1486                                        return 0;
1487                                die(symmetric
1488                                    ? "Invalid symmetric difference expression %s"
1489                                    : "Invalid revision range %s", arg);
1490                        }
1491
1492                        if (!symmetric) {
1493                                /* just A..B */
1494                                a_flags = flags_exclude;
1495                        } else {
1496                                /* A...B -- find merge bases between the two */
1497                                struct commit *a, *b;
1498                                struct commit_list *exclude;
1499
1500                                a = (a_obj->type == OBJ_COMMIT
1501                                     ? (struct commit *)a_obj
1502                                     : lookup_commit_reference(a_obj->sha1));
1503                                b = (b_obj->type == OBJ_COMMIT
1504                                     ? (struct commit *)b_obj
1505                                     : lookup_commit_reference(b_obj->sha1));
1506                                if (!a || !b)
1507                                        goto missing;
1508                                exclude = get_merge_bases(a, b);
1509                                add_rev_cmdline_list(revs, exclude,
1510                                                     REV_CMD_MERGE_BASE,
1511                                                     flags_exclude);
1512                                add_pending_commit_list(revs, exclude,
1513                                                        flags_exclude);
1514                                free_commit_list(exclude);
1515
1516                                a_flags = flags | SYMMETRIC_LEFT;
1517                        }
1518
1519                        a_obj->flags |= a_flags;
1520                        b_obj->flags |= flags;
1521                        add_rev_cmdline(revs, a_obj, this,
1522                                        REV_CMD_LEFT, a_flags);
1523                        add_rev_cmdline(revs, b_obj, next,
1524                                        REV_CMD_RIGHT, flags);
1525                        add_pending_object(revs, a_obj, this);
1526                        add_pending_object(revs, b_obj, next);
1527                        return 0;
1528                }
1529                *dotdot = '.';
1530        }
1531        dotdot = strstr(arg, "^@");
1532        if (dotdot && !dotdot[2]) {
1533                *dotdot = 0;
1534                if (add_parents_only(revs, arg, flags))
1535                        return 0;
1536                *dotdot = '^';
1537        }
1538        dotdot = strstr(arg, "^!");
1539        if (dotdot && !dotdot[2]) {
1540                *dotdot = 0;
1541                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM)))
1542                        *dotdot = '^';
1543        }
1544
1545        local_flags = 0;
1546        if (*arg == '^') {
1547                local_flags = UNINTERESTING | BOTTOM;
1548                arg++;
1549        }
1550
1551        if (revarg_opt & REVARG_COMMITTISH)
1552                get_sha1_flags = GET_SHA1_COMMITTISH;
1553
1554        if (get_sha1_with_context(arg, get_sha1_flags, sha1, &oc))
1555                return revs->ignore_missing ? 0 : -1;
1556        if (!cant_be_filename)
1557                verify_non_filename(revs->prefix, arg);
1558        object = get_reference(revs, arg, sha1, flags ^ local_flags);
1559        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1560        add_pending_object_with_mode(revs, object, arg, oc.mode);
1561        return 0;
1562}
1563
1564struct cmdline_pathspec {
1565        int alloc;
1566        int nr;
1567        const char **path;
1568};
1569
1570static void append_prune_data(struct cmdline_pathspec *prune, const char **av)
1571{
1572        while (*av) {
1573                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1574                prune->path[prune->nr++] = *(av++);
1575        }
1576}
1577
1578static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1579                                     struct cmdline_pathspec *prune)
1580{
1581        while (strbuf_getwholeline(sb, stdin, '\n') != EOF) {
1582                int len = sb->len;
1583                if (len && sb->buf[len - 1] == '\n')
1584                        sb->buf[--len] = '\0';
1585                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1586                prune->path[prune->nr++] = xstrdup(sb->buf);
1587        }
1588}
1589
1590static void read_revisions_from_stdin(struct rev_info *revs,
1591                                      struct cmdline_pathspec *prune)
1592{
1593        struct strbuf sb;
1594        int seen_dashdash = 0;
1595        int save_warning;
1596
1597        save_warning = warn_on_object_refname_ambiguity;
1598        warn_on_object_refname_ambiguity = 0;
1599
1600        strbuf_init(&sb, 1000);
1601        while (strbuf_getwholeline(&sb, stdin, '\n') != EOF) {
1602                int len = sb.len;
1603                if (len && sb.buf[len - 1] == '\n')
1604                        sb.buf[--len] = '\0';
1605                if (!len)
1606                        break;
1607                if (sb.buf[0] == '-') {
1608                        if (len == 2 && sb.buf[1] == '-') {
1609                                seen_dashdash = 1;
1610                                break;
1611                        }
1612                        die("options not supported in --stdin mode");
1613                }
1614                if (handle_revision_arg(sb.buf, revs, 0,
1615                                        REVARG_CANNOT_BE_FILENAME))
1616                        die("bad revision '%s'", sb.buf);
1617        }
1618        if (seen_dashdash)
1619                read_pathspec_from_stdin(revs, &sb, prune);
1620
1621        strbuf_release(&sb);
1622        warn_on_object_refname_ambiguity = save_warning;
1623}
1624
1625static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1626{
1627        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1628}
1629
1630static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1631{
1632        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1633}
1634
1635static void add_message_grep(struct rev_info *revs, const char *pattern)
1636{
1637        add_grep(revs, pattern, GREP_PATTERN_BODY);
1638}
1639
1640static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1641                               int *unkc, const char **unkv)
1642{
1643        const char *arg = argv[0];
1644        const char *optarg;
1645        int argcount;
1646
1647        /* pseudo revision arguments */
1648        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1649            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1650            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1651            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1652            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1653            !strcmp(arg, "--indexed-objects") ||
1654            starts_with(arg, "--exclude=") ||
1655            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1656            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1657        {
1658                unkv[(*unkc)++] = arg;
1659                return 1;
1660        }
1661
1662        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1663                revs->max_count = atoi(optarg);
1664                revs->no_walk = 0;
1665                return argcount;
1666        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1667                revs->skip_count = atoi(optarg);
1668                return argcount;
1669        } else if ((*arg == '-') && isdigit(arg[1])) {
1670                /* accept -<digit>, like traditional "head" */
1671                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1672                    revs->max_count < 0)
1673                        die("'%s': not a non-negative integer", arg + 1);
1674                revs->no_walk = 0;
1675        } else if (!strcmp(arg, "-n")) {
1676                if (argc <= 1)
1677                        return error("-n requires an argument");
1678                revs->max_count = atoi(argv[1]);
1679                revs->no_walk = 0;
1680                return 2;
1681        } else if (starts_with(arg, "-n")) {
1682                revs->max_count = atoi(arg + 2);
1683                revs->no_walk = 0;
1684        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1685                revs->max_age = atoi(optarg);
1686                return argcount;
1687        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1688                revs->max_age = approxidate(optarg);
1689                return argcount;
1690        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1691                revs->max_age = approxidate(optarg);
1692                return argcount;
1693        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1694                revs->min_age = atoi(optarg);
1695                return argcount;
1696        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1697                revs->min_age = approxidate(optarg);
1698                return argcount;
1699        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1700                revs->min_age = approxidate(optarg);
1701                return argcount;
1702        } else if (!strcmp(arg, "--first-parent")) {
1703                revs->first_parent_only = 1;
1704        } else if (!strcmp(arg, "--ancestry-path")) {
1705                revs->ancestry_path = 1;
1706                revs->simplify_history = 0;
1707                revs->limited = 1;
1708        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1709                init_reflog_walk(&revs->reflog_info);
1710        } else if (!strcmp(arg, "--default")) {
1711                if (argc <= 1)
1712                        return error("bad --default argument");
1713                revs->def = argv[1];
1714                return 2;
1715        } else if (!strcmp(arg, "--merge")) {
1716                revs->show_merge = 1;
1717        } else if (!strcmp(arg, "--topo-order")) {
1718                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1719                revs->topo_order = 1;
1720        } else if (!strcmp(arg, "--simplify-merges")) {
1721                revs->simplify_merges = 1;
1722                revs->topo_order = 1;
1723                revs->rewrite_parents = 1;
1724                revs->simplify_history = 0;
1725                revs->limited = 1;
1726        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1727                revs->simplify_merges = 1;
1728                revs->topo_order = 1;
1729                revs->rewrite_parents = 1;
1730                revs->simplify_history = 0;
1731                revs->simplify_by_decoration = 1;
1732                revs->limited = 1;
1733                revs->prune = 1;
1734                load_ref_decorations(DECORATE_SHORT_REFS);
1735        } else if (!strcmp(arg, "--date-order")) {
1736                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1737                revs->topo_order = 1;
1738        } else if (!strcmp(arg, "--author-date-order")) {
1739                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1740                revs->topo_order = 1;
1741        } else if (starts_with(arg, "--early-output")) {
1742                int count = 100;
1743                switch (arg[14]) {
1744                case '=':
1745                        count = atoi(arg+15);
1746                        /* Fallthrough */
1747                case 0:
1748                        revs->topo_order = 1;
1749                       revs->early_output = count;
1750                }
1751        } else if (!strcmp(arg, "--parents")) {
1752                revs->rewrite_parents = 1;
1753                revs->print_parents = 1;
1754        } else if (!strcmp(arg, "--dense")) {
1755                revs->dense = 1;
1756        } else if (!strcmp(arg, "--sparse")) {
1757                revs->dense = 0;
1758        } else if (!strcmp(arg, "--show-all")) {
1759                revs->show_all = 1;
1760        } else if (!strcmp(arg, "--remove-empty")) {
1761                revs->remove_empty_trees = 1;
1762        } else if (!strcmp(arg, "--merges")) {
1763                revs->min_parents = 2;
1764        } else if (!strcmp(arg, "--no-merges")) {
1765                revs->max_parents = 1;
1766        } else if (starts_with(arg, "--min-parents=")) {
1767                revs->min_parents = atoi(arg+14);
1768        } else if (starts_with(arg, "--no-min-parents")) {
1769                revs->min_parents = 0;
1770        } else if (starts_with(arg, "--max-parents=")) {
1771                revs->max_parents = atoi(arg+14);
1772        } else if (starts_with(arg, "--no-max-parents")) {
1773                revs->max_parents = -1;
1774        } else if (!strcmp(arg, "--boundary")) {
1775                revs->boundary = 1;
1776        } else if (!strcmp(arg, "--left-right")) {
1777                revs->left_right = 1;
1778        } else if (!strcmp(arg, "--left-only")) {
1779                if (revs->right_only)
1780                        die("--left-only is incompatible with --right-only"
1781                            " or --cherry");
1782                revs->left_only = 1;
1783        } else if (!strcmp(arg, "--right-only")) {
1784                if (revs->left_only)
1785                        die("--right-only is incompatible with --left-only");
1786                revs->right_only = 1;
1787        } else if (!strcmp(arg, "--cherry")) {
1788                if (revs->left_only)
1789                        die("--cherry is incompatible with --left-only");
1790                revs->cherry_mark = 1;
1791                revs->right_only = 1;
1792                revs->max_parents = 1;
1793                revs->limited = 1;
1794        } else if (!strcmp(arg, "--count")) {
1795                revs->count = 1;
1796        } else if (!strcmp(arg, "--cherry-mark")) {
1797                if (revs->cherry_pick)
1798                        die("--cherry-mark is incompatible with --cherry-pick");
1799                revs->cherry_mark = 1;
1800                revs->limited = 1; /* needs limit_list() */
1801        } else if (!strcmp(arg, "--cherry-pick")) {
1802                if (revs->cherry_mark)
1803                        die("--cherry-pick is incompatible with --cherry-mark");
1804                revs->cherry_pick = 1;
1805                revs->limited = 1;
1806        } else if (!strcmp(arg, "--objects")) {
1807                revs->tag_objects = 1;
1808                revs->tree_objects = 1;
1809                revs->blob_objects = 1;
1810        } else if (!strcmp(arg, "--objects-edge")) {
1811                revs->tag_objects = 1;
1812                revs->tree_objects = 1;
1813                revs->blob_objects = 1;
1814                revs->edge_hint = 1;
1815        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1816                revs->tag_objects = 1;
1817                revs->tree_objects = 1;
1818                revs->blob_objects = 1;
1819                revs->edge_hint = 1;
1820                revs->edge_hint_aggressive = 1;
1821        } else if (!strcmp(arg, "--verify-objects")) {
1822                revs->tag_objects = 1;
1823                revs->tree_objects = 1;
1824                revs->blob_objects = 1;
1825                revs->verify_objects = 1;
1826        } else if (!strcmp(arg, "--unpacked")) {
1827                revs->unpacked = 1;
1828        } else if (starts_with(arg, "--unpacked=")) {
1829                die("--unpacked=<packfile> no longer supported.");
1830        } else if (!strcmp(arg, "-r")) {
1831                revs->diff = 1;
1832                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1833        } else if (!strcmp(arg, "-t")) {
1834                revs->diff = 1;
1835                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1836                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1837        } else if (!strcmp(arg, "-m")) {
1838                revs->ignore_merges = 0;
1839        } else if (!strcmp(arg, "-c")) {
1840                revs->diff = 1;
1841                revs->dense_combined_merges = 0;
1842                revs->combine_merges = 1;
1843        } else if (!strcmp(arg, "--cc")) {
1844                revs->diff = 1;
1845                revs->dense_combined_merges = 1;
1846                revs->combine_merges = 1;
1847        } else if (!strcmp(arg, "-v")) {
1848                revs->verbose_header = 1;
1849        } else if (!strcmp(arg, "--pretty")) {
1850                revs->verbose_header = 1;
1851                revs->pretty_given = 1;
1852                get_commit_format(NULL, revs);
1853        } else if (starts_with(arg, "--pretty=") || starts_with(arg, "--format=")) {
1854                /*
1855                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1856                 * not allowed, since the argument is optional.
1857                 */
1858                revs->verbose_header = 1;
1859                revs->pretty_given = 1;
1860                get_commit_format(arg+9, revs);
1861        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1862                revs->show_notes = 1;
1863                revs->show_notes_given = 1;
1864                revs->notes_opt.use_default_notes = 1;
1865        } else if (!strcmp(arg, "--show-signature")) {
1866                revs->show_signature = 1;
1867        } else if (!strcmp(arg, "--show-linear-break") ||
1868                   starts_with(arg, "--show-linear-break=")) {
1869                if (starts_with(arg, "--show-linear-break="))
1870                        revs->break_bar = xstrdup(arg + 20);
1871                else
1872                        revs->break_bar = "                    ..........";
1873                revs->track_linear = 1;
1874                revs->track_first_time = 1;
1875        } else if (starts_with(arg, "--show-notes=") ||
1876                   starts_with(arg, "--notes=")) {
1877                struct strbuf buf = STRBUF_INIT;
1878                revs->show_notes = 1;
1879                revs->show_notes_given = 1;
1880                if (starts_with(arg, "--show-notes")) {
1881                        if (revs->notes_opt.use_default_notes < 0)
1882                                revs->notes_opt.use_default_notes = 1;
1883                        strbuf_addstr(&buf, arg+13);
1884                }
1885                else
1886                        strbuf_addstr(&buf, arg+8);
1887                expand_notes_ref(&buf);
1888                string_list_append(&revs->notes_opt.extra_notes_refs,
1889                                   strbuf_detach(&buf, NULL));
1890        } else if (!strcmp(arg, "--no-notes")) {
1891                revs->show_notes = 0;
1892                revs->show_notes_given = 1;
1893                revs->notes_opt.use_default_notes = -1;
1894                /* we have been strdup'ing ourselves, so trick
1895                 * string_list into free()ing strings */
1896                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
1897                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
1898                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
1899        } else if (!strcmp(arg, "--standard-notes")) {
1900                revs->show_notes_given = 1;
1901                revs->notes_opt.use_default_notes = 1;
1902        } else if (!strcmp(arg, "--no-standard-notes")) {
1903                revs->notes_opt.use_default_notes = 0;
1904        } else if (!strcmp(arg, "--oneline")) {
1905                revs->verbose_header = 1;
1906                get_commit_format("oneline", revs);
1907                revs->pretty_given = 1;
1908                revs->abbrev_commit = 1;
1909        } else if (!strcmp(arg, "--graph")) {
1910                revs->topo_order = 1;
1911                revs->rewrite_parents = 1;
1912                revs->graph = graph_init(revs);
1913        } else if (!strcmp(arg, "--root")) {
1914                revs->show_root_diff = 1;
1915        } else if (!strcmp(arg, "--no-commit-id")) {
1916                revs->no_commit_id = 1;
1917        } else if (!strcmp(arg, "--always")) {
1918                revs->always_show_header = 1;
1919        } else if (!strcmp(arg, "--no-abbrev")) {
1920                revs->abbrev = 0;
1921        } else if (!strcmp(arg, "--abbrev")) {
1922                revs->abbrev = DEFAULT_ABBREV;
1923        } else if (starts_with(arg, "--abbrev=")) {
1924                revs->abbrev = strtoul(arg + 9, NULL, 10);
1925                if (revs->abbrev < MINIMUM_ABBREV)
1926                        revs->abbrev = MINIMUM_ABBREV;
1927                else if (revs->abbrev > 40)
1928                        revs->abbrev = 40;
1929        } else if (!strcmp(arg, "--abbrev-commit")) {
1930                revs->abbrev_commit = 1;
1931                revs->abbrev_commit_given = 1;
1932        } else if (!strcmp(arg, "--no-abbrev-commit")) {
1933                revs->abbrev_commit = 0;
1934        } else if (!strcmp(arg, "--full-diff")) {
1935                revs->diff = 1;
1936                revs->full_diff = 1;
1937        } else if (!strcmp(arg, "--full-history")) {
1938                revs->simplify_history = 0;
1939        } else if (!strcmp(arg, "--relative-date")) {
1940                revs->date_mode = DATE_RELATIVE;
1941                revs->date_mode_explicit = 1;
1942        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
1943                revs->date_mode = parse_date_format(optarg);
1944                revs->date_mode_explicit = 1;
1945                return argcount;
1946        } else if (!strcmp(arg, "--log-size")) {
1947                revs->show_log_size = 1;
1948        }
1949        /*
1950         * Grepping the commit log
1951         */
1952        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
1953                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
1954                return argcount;
1955        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
1956                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
1957                return argcount;
1958        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
1959                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
1960                return argcount;
1961        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
1962                add_message_grep(revs, optarg);
1963                return argcount;
1964        } else if (!strcmp(arg, "--grep-debug")) {
1965                revs->grep_filter.debug = 1;
1966        } else if (!strcmp(arg, "--basic-regexp")) {
1967                grep_set_pattern_type_option(GREP_PATTERN_TYPE_BRE, &revs->grep_filter);
1968        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
1969                grep_set_pattern_type_option(GREP_PATTERN_TYPE_ERE, &revs->grep_filter);
1970        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
1971                revs->grep_filter.regflags |= REG_ICASE;
1972                DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
1973        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
1974                grep_set_pattern_type_option(GREP_PATTERN_TYPE_FIXED, &revs->grep_filter);
1975        } else if (!strcmp(arg, "--perl-regexp")) {
1976                grep_set_pattern_type_option(GREP_PATTERN_TYPE_PCRE, &revs->grep_filter);
1977        } else if (!strcmp(arg, "--all-match")) {
1978                revs->grep_filter.all_match = 1;
1979        } else if (!strcmp(arg, "--invert-grep")) {
1980                revs->invert_grep = 1;
1981        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
1982                if (strcmp(optarg, "none"))
1983                        git_log_output_encoding = xstrdup(optarg);
1984                else
1985                        git_log_output_encoding = "";
1986                return argcount;
1987        } else if (!strcmp(arg, "--reverse")) {
1988                revs->reverse ^= 1;
1989        } else if (!strcmp(arg, "--children")) {
1990                revs->children.name = "children";
1991                revs->limited = 1;
1992        } else if (!strcmp(arg, "--ignore-missing")) {
1993                revs->ignore_missing = 1;
1994        } else {
1995                int opts = diff_opt_parse(&revs->diffopt, argv, argc);
1996                if (!opts)
1997                        unkv[(*unkc)++] = arg;
1998                return opts;
1999        }
2000        if (revs->graph && revs->track_linear)
2001                die("--show-linear-break and --graph are incompatible");
2002
2003        return 1;
2004}
2005
2006void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2007                        const struct option *options,
2008                        const char * const usagestr[])
2009{
2010        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2011                                    &ctx->cpidx, ctx->out);
2012        if (n <= 0) {
2013                error("unknown option `%s'", ctx->argv[0]);
2014                usage_with_options(usagestr, options);
2015        }
2016        ctx->argv += n;
2017        ctx->argc -= n;
2018}
2019
2020static int for_each_bad_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
2021{
2022        return for_each_ref_in_submodule(submodule, "refs/bisect/bad", fn, cb_data);
2023}
2024
2025static int for_each_good_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
2026{
2027        return for_each_ref_in_submodule(submodule, "refs/bisect/good", fn, cb_data);
2028}
2029
2030static int handle_revision_pseudo_opt(const char *submodule,
2031                                struct rev_info *revs,
2032                                int argc, const char **argv, int *flags)
2033{
2034        const char *arg = argv[0];
2035        const char *optarg;
2036        int argcount;
2037
2038        /*
2039         * NOTE!
2040         *
2041         * Commands like "git shortlog" will not accept the options below
2042         * unless parse_revision_opt queues them (as opposed to erroring
2043         * out).
2044         *
2045         * When implementing your new pseudo-option, remember to
2046         * register it in the list at the top of handle_revision_opt.
2047         */
2048        if (!strcmp(arg, "--all")) {
2049                handle_refs(submodule, revs, *flags, for_each_ref_submodule);
2050                handle_refs(submodule, revs, *flags, head_ref_submodule);
2051                clear_ref_exclusion(&revs->ref_excludes);
2052        } else if (!strcmp(arg, "--branches")) {
2053                handle_refs(submodule, revs, *flags, for_each_branch_ref_submodule);
2054                clear_ref_exclusion(&revs->ref_excludes);
2055        } else if (!strcmp(arg, "--bisect")) {
2056                handle_refs(submodule, revs, *flags, for_each_bad_bisect_ref);
2057                handle_refs(submodule, revs, *flags ^ (UNINTERESTING | BOTTOM), for_each_good_bisect_ref);
2058                revs->bisect = 1;
2059        } else if (!strcmp(arg, "--tags")) {
2060                handle_refs(submodule, revs, *flags, for_each_tag_ref_submodule);
2061                clear_ref_exclusion(&revs->ref_excludes);
2062        } else if (!strcmp(arg, "--remotes")) {
2063                handle_refs(submodule, revs, *flags, for_each_remote_ref_submodule);
2064                clear_ref_exclusion(&revs->ref_excludes);
2065        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2066                struct all_refs_cb cb;
2067                init_all_refs_cb(&cb, revs, *flags);
2068                for_each_glob_ref(handle_one_ref, optarg, &cb);
2069                clear_ref_exclusion(&revs->ref_excludes);
2070                return argcount;
2071        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2072                add_ref_exclusion(&revs->ref_excludes, optarg);
2073                return argcount;
2074        } else if (starts_with(arg, "--branches=")) {
2075                struct all_refs_cb cb;
2076                init_all_refs_cb(&cb, revs, *flags);
2077                for_each_glob_ref_in(handle_one_ref, arg + 11, "refs/heads/", &cb);
2078                clear_ref_exclusion(&revs->ref_excludes);
2079        } else if (starts_with(arg, "--tags=")) {
2080                struct all_refs_cb cb;
2081                init_all_refs_cb(&cb, revs, *flags);
2082                for_each_glob_ref_in(handle_one_ref, arg + 7, "refs/tags/", &cb);
2083                clear_ref_exclusion(&revs->ref_excludes);
2084        } else if (starts_with(arg, "--remotes=")) {
2085                struct all_refs_cb cb;
2086                init_all_refs_cb(&cb, revs, *flags);
2087                for_each_glob_ref_in(handle_one_ref, arg + 10, "refs/remotes/", &cb);
2088                clear_ref_exclusion(&revs->ref_excludes);
2089        } else if (!strcmp(arg, "--reflog")) {
2090                add_reflogs_to_pending(revs, *flags);
2091        } else if (!strcmp(arg, "--indexed-objects")) {
2092                add_index_objects_to_pending(revs, *flags);
2093        } else if (!strcmp(arg, "--not")) {
2094                *flags ^= UNINTERESTING | BOTTOM;
2095        } else if (!strcmp(arg, "--no-walk")) {
2096                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2097        } else if (starts_with(arg, "--no-walk=")) {
2098                /*
2099                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2100                 * not allowed, since the argument is optional.
2101                 */
2102                if (!strcmp(arg + 10, "sorted"))
2103                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2104                else if (!strcmp(arg + 10, "unsorted"))
2105                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2106                else
2107                        return error("invalid argument to --no-walk");
2108        } else if (!strcmp(arg, "--do-walk")) {
2109                revs->no_walk = 0;
2110        } else {
2111                return 0;
2112        }
2113
2114        return 1;
2115}
2116
2117/*
2118 * Parse revision information, filling in the "rev_info" structure,
2119 * and removing the used arguments from the argument list.
2120 *
2121 * Returns the number of arguments left that weren't recognized
2122 * (which are also moved to the head of the argument list)
2123 */
2124int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2125{
2126        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2127        struct cmdline_pathspec prune_data;
2128        const char *submodule = NULL;
2129
2130        memset(&prune_data, 0, sizeof(prune_data));
2131        if (opt)
2132                submodule = opt->submodule;
2133
2134        /* First, search for "--" */
2135        if (opt && opt->assume_dashdash) {
2136                seen_dashdash = 1;
2137        } else {
2138                seen_dashdash = 0;
2139                for (i = 1; i < argc; i++) {
2140                        const char *arg = argv[i];
2141                        if (strcmp(arg, "--"))
2142                                continue;
2143                        argv[i] = NULL;
2144                        argc = i;
2145                        if (argv[i + 1])
2146                                append_prune_data(&prune_data, argv + i + 1);
2147                        seen_dashdash = 1;
2148                        break;
2149                }
2150        }
2151
2152        /* Second, deal with arguments and options */
2153        flags = 0;
2154        revarg_opt = opt ? opt->revarg_opt : 0;
2155        if (seen_dashdash)
2156                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2157        read_from_stdin = 0;
2158        for (left = i = 1; i < argc; i++) {
2159                const char *arg = argv[i];
2160                if (*arg == '-') {
2161                        int opts;
2162
2163                        opts = handle_revision_pseudo_opt(submodule,
2164                                                revs, argc - i, argv + i,
2165                                                &flags);
2166                        if (opts > 0) {
2167                                i += opts - 1;
2168                                continue;
2169                        }
2170
2171                        if (!strcmp(arg, "--stdin")) {
2172                                if (revs->disable_stdin) {
2173                                        argv[left++] = arg;
2174                                        continue;
2175                                }
2176                                if (read_from_stdin++)
2177                                        die("--stdin given twice?");
2178                                read_revisions_from_stdin(revs, &prune_data);
2179                                continue;
2180                        }
2181
2182                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2183                        if (opts > 0) {
2184                                i += opts - 1;
2185                                continue;
2186                        }
2187                        if (opts < 0)
2188                                exit(128);
2189                        continue;
2190                }
2191
2192
2193                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2194                        int j;
2195                        if (seen_dashdash || *arg == '^')
2196                                die("bad revision '%s'", arg);
2197
2198                        /* If we didn't have a "--":
2199                         * (1) all filenames must exist;
2200                         * (2) all rev-args must not be interpretable
2201                         *     as a valid filename.
2202                         * but the latter we have checked in the main loop.
2203                         */
2204                        for (j = i; j < argc; j++)
2205                                verify_filename(revs->prefix, argv[j], j == i);
2206
2207                        append_prune_data(&prune_data, argv + i);
2208                        break;
2209                }
2210                else
2211                        got_rev_arg = 1;
2212        }
2213
2214        if (prune_data.nr) {
2215                /*
2216                 * If we need to introduce the magic "a lone ':' means no
2217                 * pathspec whatsoever", here is the place to do so.
2218                 *
2219                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2220                 *      prune_data.nr = 0;
2221                 *      prune_data.alloc = 0;
2222                 *      free(prune_data.path);
2223                 *      prune_data.path = NULL;
2224                 * } else {
2225                 *      terminate prune_data.alloc with NULL and
2226                 *      call init_pathspec() to set revs->prune_data here.
2227                 * }
2228                 */
2229                ALLOC_GROW(prune_data.path, prune_data.nr + 1, prune_data.alloc);
2230                prune_data.path[prune_data.nr++] = NULL;
2231                parse_pathspec(&revs->prune_data, 0, 0,
2232                               revs->prefix, prune_data.path);
2233        }
2234
2235        if (revs->def == NULL)
2236                revs->def = opt ? opt->def : NULL;
2237        if (opt && opt->tweak)
2238                opt->tweak(revs, opt);
2239        if (revs->show_merge)
2240                prepare_show_merge(revs);
2241        if (revs->def && !revs->pending.nr && !got_rev_arg) {
2242                unsigned char sha1[20];
2243                struct object *object;
2244                struct object_context oc;
2245                if (get_sha1_with_context(revs->def, 0, sha1, &oc))
2246                        die("bad default revision '%s'", revs->def);
2247                object = get_reference(revs, revs->def, sha1, 0);
2248                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2249        }
2250
2251        /* Did the user ask for any diff output? Run the diff! */
2252        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2253                revs->diff = 1;
2254
2255        /* Pickaxe, diff-filter and rename following need diffs */
2256        if (revs->diffopt.pickaxe ||
2257            revs->diffopt.filter ||
2258            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2259                revs->diff = 1;
2260
2261        if (revs->topo_order)
2262                revs->limited = 1;
2263
2264        if (revs->prune_data.nr) {
2265                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2266                /* Can't prune commits with rename following: the paths change.. */
2267                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2268                        revs->prune = 1;
2269                if (!revs->full_diff)
2270                        copy_pathspec(&revs->diffopt.pathspec,
2271                                      &revs->prune_data);
2272        }
2273        if (revs->combine_merges)
2274                revs->ignore_merges = 0;
2275        revs->diffopt.abbrev = revs->abbrev;
2276
2277        if (revs->line_level_traverse) {
2278                revs->limited = 1;
2279                revs->topo_order = 1;
2280        }
2281
2282        diff_setup_done(&revs->diffopt);
2283
2284        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2285                                 &revs->grep_filter);
2286        compile_grep_patterns(&revs->grep_filter);
2287
2288        if (revs->reverse && revs->reflog_info)
2289                die("cannot combine --reverse with --walk-reflogs");
2290        if (revs->rewrite_parents && revs->children.name)
2291                die("cannot combine --parents and --children");
2292
2293        /*
2294         * Limitations on the graph functionality
2295         */
2296        if (revs->reverse && revs->graph)
2297                die("cannot combine --reverse with --graph");
2298
2299        if (revs->reflog_info && revs->graph)
2300                die("cannot combine --walk-reflogs with --graph");
2301        if (revs->no_walk && revs->graph)
2302                die("cannot combine --no-walk with --graph");
2303        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2304                die("cannot use --grep-reflog without --walk-reflogs");
2305
2306        if (revs->first_parent_only && revs->bisect)
2307                die(_("--first-parent is incompatible with --bisect"));
2308
2309        return left;
2310}
2311
2312static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2313{
2314        struct commit_list *l = xcalloc(1, sizeof(*l));
2315
2316        l->item = child;
2317        l->next = add_decoration(&revs->children, &parent->object, l);
2318}
2319
2320static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2321{
2322        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2323        struct commit_list **pp, *p;
2324        int surviving_parents;
2325
2326        /* Examine existing parents while marking ones we have seen... */
2327        pp = &commit->parents;
2328        surviving_parents = 0;
2329        while ((p = *pp) != NULL) {
2330                struct commit *parent = p->item;
2331                if (parent->object.flags & TMP_MARK) {
2332                        *pp = p->next;
2333                        if (ts)
2334                                compact_treesame(revs, commit, surviving_parents);
2335                        continue;
2336                }
2337                parent->object.flags |= TMP_MARK;
2338                surviving_parents++;
2339                pp = &p->next;
2340        }
2341        /* clear the temporary mark */
2342        for (p = commit->parents; p; p = p->next) {
2343                p->item->object.flags &= ~TMP_MARK;
2344        }
2345        /* no update_treesame() - removing duplicates can't affect TREESAME */
2346        return surviving_parents;
2347}
2348
2349struct merge_simplify_state {
2350        struct commit *simplified;
2351};
2352
2353static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2354{
2355        struct merge_simplify_state *st;
2356
2357        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2358        if (!st) {
2359                st = xcalloc(1, sizeof(*st));
2360                add_decoration(&revs->merge_simplification, &commit->object, st);
2361        }
2362        return st;
2363}
2364
2365static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2366{
2367        struct commit_list *h = reduce_heads(commit->parents);
2368        int i = 0, marked = 0;
2369        struct commit_list *po, *pn;
2370
2371        /* Want these for sanity-checking only */
2372        int orig_cnt = commit_list_count(commit->parents);
2373        int cnt = commit_list_count(h);
2374
2375        /*
2376         * Not ready to remove items yet, just mark them for now, based
2377         * on the output of reduce_heads(). reduce_heads outputs the reduced
2378         * set in its original order, so this isn't too hard.
2379         */
2380        po = commit->parents;
2381        pn = h;
2382        while (po) {
2383                if (pn && po->item == pn->item) {
2384                        pn = pn->next;
2385                        i++;
2386                } else {
2387                        po->item->object.flags |= TMP_MARK;
2388                        marked++;
2389                }
2390                po=po->next;
2391        }
2392
2393        if (i != cnt || cnt+marked != orig_cnt)
2394                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2395
2396        free_commit_list(h);
2397
2398        return marked;
2399}
2400
2401static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2402{
2403        struct commit_list *p;
2404        int marked = 0;
2405
2406        for (p = commit->parents; p; p = p->next) {
2407                struct commit *parent = p->item;
2408                if (!parent->parents && (parent->object.flags & TREESAME)) {
2409                        parent->object.flags |= TMP_MARK;
2410                        marked++;
2411                }
2412        }
2413
2414        return marked;
2415}
2416
2417/*
2418 * Awkward naming - this means one parent we are TREESAME to.
2419 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2420 * empty tree). Better name suggestions?
2421 */
2422static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2423{
2424        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2425        struct commit *unmarked = NULL, *marked = NULL;
2426        struct commit_list *p;
2427        unsigned n;
2428
2429        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2430                if (ts->treesame[n]) {
2431                        if (p->item->object.flags & TMP_MARK) {
2432                                if (!marked)
2433                                        marked = p->item;
2434                        } else {
2435                                if (!unmarked) {
2436                                        unmarked = p->item;
2437                                        break;
2438                                }
2439                        }
2440                }
2441        }
2442
2443        /*
2444         * If we are TREESAME to a marked-for-deletion parent, but not to any
2445         * unmarked parents, unmark the first TREESAME parent. This is the
2446         * parent that the default simplify_history==1 scan would have followed,
2447         * and it doesn't make sense to omit that path when asking for a
2448         * simplified full history. Retaining it improves the chances of
2449         * understanding odd missed merges that took an old version of a file.
2450         *
2451         * Example:
2452         *
2453         *   I--------*X       A modified the file, but mainline merge X used
2454         *    \       /        "-s ours", so took the version from I. X is
2455         *     `-*A--'         TREESAME to I and !TREESAME to A.
2456         *
2457         * Default log from X would produce "I". Without this check,
2458         * --full-history --simplify-merges would produce "I-A-X", showing
2459         * the merge commit X and that it changed A, but not making clear that
2460         * it had just taken the I version. With this check, the topology above
2461         * is retained.
2462         *
2463         * Note that it is possible that the simplification chooses a different
2464         * TREESAME parent from the default, in which case this test doesn't
2465         * activate, and we _do_ drop the default parent. Example:
2466         *
2467         *   I------X         A modified the file, but it was reverted in B,
2468         *    \    /          meaning mainline merge X is TREESAME to both
2469         *    *A-*B           parents.
2470         *
2471         * Default log would produce "I" by following the first parent;
2472         * --full-history --simplify-merges will produce "I-A-B". But this is a
2473         * reasonable result - it presents a logical full history leading from
2474         * I to X, and X is not an important merge.
2475         */
2476        if (!unmarked && marked) {
2477                marked->object.flags &= ~TMP_MARK;
2478                return 1;
2479        }
2480
2481        return 0;
2482}
2483
2484static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2485{
2486        struct commit_list **pp, *p;
2487        int nth_parent, removed = 0;
2488
2489        pp = &commit->parents;
2490        nth_parent = 0;
2491        while ((p = *pp) != NULL) {
2492                struct commit *parent = p->item;
2493                if (parent->object.flags & TMP_MARK) {
2494                        parent->object.flags &= ~TMP_MARK;
2495                        *pp = p->next;
2496                        free(p);
2497                        removed++;
2498                        compact_treesame(revs, commit, nth_parent);
2499                        continue;
2500                }
2501                pp = &p->next;
2502                nth_parent++;
2503        }
2504
2505        /* Removing parents can only increase TREESAMEness */
2506        if (removed && !(commit->object.flags & TREESAME))
2507                update_treesame(revs, commit);
2508
2509        return nth_parent;
2510}
2511
2512static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2513{
2514        struct commit_list *p;
2515        struct commit *parent;
2516        struct merge_simplify_state *st, *pst;
2517        int cnt;
2518
2519        st = locate_simplify_state(revs, commit);
2520
2521        /*
2522         * Have we handled this one?
2523         */
2524        if (st->simplified)
2525                return tail;
2526
2527        /*
2528         * An UNINTERESTING commit simplifies to itself, so does a
2529         * root commit.  We do not rewrite parents of such commit
2530         * anyway.
2531         */
2532        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2533                st->simplified = commit;
2534                return tail;
2535        }
2536
2537        /*
2538         * Do we know what commit all of our parents that matter
2539         * should be rewritten to?  Otherwise we are not ready to
2540         * rewrite this one yet.
2541         */
2542        for (cnt = 0, p = commit->parents; p; p = p->next) {
2543                pst = locate_simplify_state(revs, p->item);
2544                if (!pst->simplified) {
2545                        tail = &commit_list_insert(p->item, tail)->next;
2546                        cnt++;
2547                }
2548                if (revs->first_parent_only)
2549                        break;
2550        }
2551        if (cnt) {
2552                tail = &commit_list_insert(commit, tail)->next;
2553                return tail;
2554        }
2555
2556        /*
2557         * Rewrite our list of parents. Note that this cannot
2558         * affect our TREESAME flags in any way - a commit is
2559         * always TREESAME to its simplification.
2560         */
2561        for (p = commit->parents; p; p = p->next) {
2562                pst = locate_simplify_state(revs, p->item);
2563                p->item = pst->simplified;
2564                if (revs->first_parent_only)
2565                        break;
2566        }
2567
2568        if (revs->first_parent_only)
2569                cnt = 1;
2570        else
2571                cnt = remove_duplicate_parents(revs, commit);
2572
2573        /*
2574         * It is possible that we are a merge and one side branch
2575         * does not have any commit that touches the given paths;
2576         * in such a case, the immediate parent from that branch
2577         * will be rewritten to be the merge base.
2578         *
2579         *      o----X          X: the commit we are looking at;
2580         *     /    /           o: a commit that touches the paths;
2581         * ---o----'
2582         *
2583         * Further, a merge of an independent branch that doesn't
2584         * touch the path will reduce to a treesame root parent:
2585         *
2586         *  ----o----X          X: the commit we are looking at;
2587         *          /           o: a commit that touches the paths;
2588         *         r            r: a root commit not touching the paths
2589         *
2590         * Detect and simplify both cases.
2591         */
2592        if (1 < cnt) {
2593                int marked = mark_redundant_parents(revs, commit);
2594                marked += mark_treesame_root_parents(revs, commit);
2595                if (marked)
2596                        marked -= leave_one_treesame_to_parent(revs, commit);
2597                if (marked)
2598                        cnt = remove_marked_parents(revs, commit);
2599        }
2600
2601        /*
2602         * A commit simplifies to itself if it is a root, if it is
2603         * UNINTERESTING, if it touches the given paths, or if it is a
2604         * merge and its parents don't simplify to one relevant commit
2605         * (the first two cases are already handled at the beginning of
2606         * this function).
2607         *
2608         * Otherwise, it simplifies to what its sole relevant parent
2609         * simplifies to.
2610         */
2611        if (!cnt ||
2612            (commit->object.flags & UNINTERESTING) ||
2613            !(commit->object.flags & TREESAME) ||
2614            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2615                st->simplified = commit;
2616        else {
2617                pst = locate_simplify_state(revs, parent);
2618                st->simplified = pst->simplified;
2619        }
2620        return tail;
2621}
2622
2623static void simplify_merges(struct rev_info *revs)
2624{
2625        struct commit_list *list, *next;
2626        struct commit_list *yet_to_do, **tail;
2627        struct commit *commit;
2628
2629        if (!revs->prune)
2630                return;
2631
2632        /* feed the list reversed */
2633        yet_to_do = NULL;
2634        for (list = revs->commits; list; list = next) {
2635                commit = list->item;
2636                next = list->next;
2637                /*
2638                 * Do not free(list) here yet; the original list
2639                 * is used later in this function.
2640                 */
2641                commit_list_insert(commit, &yet_to_do);
2642        }
2643        while (yet_to_do) {
2644                list = yet_to_do;
2645                yet_to_do = NULL;
2646                tail = &yet_to_do;
2647                while (list) {
2648                        commit = list->item;
2649                        next = list->next;
2650                        free(list);
2651                        list = next;
2652                        tail = simplify_one(revs, commit, tail);
2653                }
2654        }
2655
2656        /* clean up the result, removing the simplified ones */
2657        list = revs->commits;
2658        revs->commits = NULL;
2659        tail = &revs->commits;
2660        while (list) {
2661                struct merge_simplify_state *st;
2662
2663                commit = list->item;
2664                next = list->next;
2665                free(list);
2666                list = next;
2667                st = locate_simplify_state(revs, commit);
2668                if (st->simplified == commit)
2669                        tail = &commit_list_insert(commit, tail)->next;
2670        }
2671}
2672
2673static void set_children(struct rev_info *revs)
2674{
2675        struct commit_list *l;
2676        for (l = revs->commits; l; l = l->next) {
2677                struct commit *commit = l->item;
2678                struct commit_list *p;
2679
2680                for (p = commit->parents; p; p = p->next)
2681                        add_child(revs, p->item, commit);
2682        }
2683}
2684
2685void reset_revision_walk(void)
2686{
2687        clear_object_flags(SEEN | ADDED | SHOWN);
2688}
2689
2690int prepare_revision_walk(struct rev_info *revs)
2691{
2692        int i;
2693        struct object_array old_pending;
2694        struct commit_list **next = &revs->commits;
2695
2696        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2697        revs->pending.nr = 0;
2698        revs->pending.alloc = 0;
2699        revs->pending.objects = NULL;
2700        for (i = 0; i < old_pending.nr; i++) {
2701                struct object_array_entry *e = old_pending.objects + i;
2702                struct commit *commit = handle_commit(revs, e);
2703                if (commit) {
2704                        if (!(commit->object.flags & SEEN)) {
2705                                commit->object.flags |= SEEN;
2706                                next = commit_list_append(commit, next);
2707                        }
2708                }
2709        }
2710        if (!revs->leak_pending)
2711                object_array_clear(&old_pending);
2712
2713        /* Signal whether we need per-parent treesame decoration */
2714        if (revs->simplify_merges ||
2715            (revs->limited && limiting_can_increase_treesame(revs)))
2716                revs->treesame.name = "treesame";
2717
2718        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2719                commit_list_sort_by_date(&revs->commits);
2720        if (revs->no_walk)
2721                return 0;
2722        if (revs->limited)
2723                if (limit_list(revs) < 0)
2724                        return -1;
2725        if (revs->topo_order)
2726                sort_in_topological_order(&revs->commits, revs->sort_order);
2727        if (revs->line_level_traverse)
2728                line_log_filter(revs);
2729        if (revs->simplify_merges)
2730                simplify_merges(revs);
2731        if (revs->children.name)
2732                set_children(revs);
2733        return 0;
2734}
2735
2736static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2737{
2738        struct commit_list *cache = NULL;
2739
2740        for (;;) {
2741                struct commit *p = *pp;
2742                if (!revs->limited)
2743                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2744                                return rewrite_one_error;
2745                if (p->object.flags & UNINTERESTING)
2746                        return rewrite_one_ok;
2747                if (!(p->object.flags & TREESAME))
2748                        return rewrite_one_ok;
2749                if (!p->parents)
2750                        return rewrite_one_noparents;
2751                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2752                        return rewrite_one_ok;
2753                *pp = p;
2754        }
2755}
2756
2757int rewrite_parents(struct rev_info *revs, struct commit *commit,
2758        rewrite_parent_fn_t rewrite_parent)
2759{
2760        struct commit_list **pp = &commit->parents;
2761        while (*pp) {
2762                struct commit_list *parent = *pp;
2763                switch (rewrite_parent(revs, &parent->item)) {
2764                case rewrite_one_ok:
2765                        break;
2766                case rewrite_one_noparents:
2767                        *pp = parent->next;
2768                        continue;
2769                case rewrite_one_error:
2770                        return -1;
2771                }
2772                pp = &parent->next;
2773        }
2774        remove_duplicate_parents(revs, commit);
2775        return 0;
2776}
2777
2778static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2779{
2780        char *person, *endp;
2781        size_t len, namelen, maillen;
2782        const char *name;
2783        const char *mail;
2784        struct ident_split ident;
2785
2786        person = strstr(buf->buf, what);
2787        if (!person)
2788                return 0;
2789
2790        person += strlen(what);
2791        endp = strchr(person, '\n');
2792        if (!endp)
2793                return 0;
2794
2795        len = endp - person;
2796
2797        if (split_ident_line(&ident, person, len))
2798                return 0;
2799
2800        mail = ident.mail_begin;
2801        maillen = ident.mail_end - ident.mail_begin;
2802        name = ident.name_begin;
2803        namelen = ident.name_end - ident.name_begin;
2804
2805        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2806                struct strbuf namemail = STRBUF_INIT;
2807
2808                strbuf_addf(&namemail, "%.*s <%.*s>",
2809                            (int)namelen, name, (int)maillen, mail);
2810
2811                strbuf_splice(buf, ident.name_begin - buf->buf,
2812                              ident.mail_end - ident.name_begin + 1,
2813                              namemail.buf, namemail.len);
2814
2815                strbuf_release(&namemail);
2816
2817                return 1;
2818        }
2819
2820        return 0;
2821}
2822
2823static int commit_match(struct commit *commit, struct rev_info *opt)
2824{
2825        int retval;
2826        const char *encoding;
2827        const char *message;
2828        struct strbuf buf = STRBUF_INIT;
2829
2830        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2831                return 1;
2832
2833        /* Prepend "fake" headers as needed */
2834        if (opt->grep_filter.use_reflog_filter) {
2835                strbuf_addstr(&buf, "reflog ");
2836                get_reflog_message(&buf, opt->reflog_info);
2837                strbuf_addch(&buf, '\n');
2838        }
2839
2840        /*
2841         * We grep in the user's output encoding, under the assumption that it
2842         * is the encoding they are most likely to write their grep pattern
2843         * for. In addition, it means we will match the "notes" encoding below,
2844         * so we will not end up with a buffer that has two different encodings
2845         * in it.
2846         */
2847        encoding = get_log_output_encoding();
2848        message = logmsg_reencode(commit, NULL, encoding);
2849
2850        /* Copy the commit to temporary if we are using "fake" headers */
2851        if (buf.len)
2852                strbuf_addstr(&buf, message);
2853
2854        if (opt->grep_filter.header_list && opt->mailmap) {
2855                if (!buf.len)
2856                        strbuf_addstr(&buf, message);
2857
2858                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
2859                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
2860        }
2861
2862        /* Append "fake" message parts as needed */
2863        if (opt->show_notes) {
2864                if (!buf.len)
2865                        strbuf_addstr(&buf, message);
2866                format_display_notes(commit->object.sha1, &buf, encoding, 1);
2867        }
2868
2869        /*
2870         * Find either in the original commit message, or in the temporary.
2871         * Note that we cast away the constness of "message" here. It is
2872         * const because it may come from the cached commit buffer. That's OK,
2873         * because we know that it is modifiable heap memory, and that while
2874         * grep_buffer may modify it for speed, it will restore any
2875         * changes before returning.
2876         */
2877        if (buf.len)
2878                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
2879        else
2880                retval = grep_buffer(&opt->grep_filter,
2881                                     (char *)message, strlen(message));
2882        strbuf_release(&buf);
2883        unuse_commit_buffer(commit, message);
2884        return opt->invert_grep ? !retval : retval;
2885}
2886
2887static inline int want_ancestry(const struct rev_info *revs)
2888{
2889        return (revs->rewrite_parents || revs->children.name);
2890}
2891
2892enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
2893{
2894        if (commit->object.flags & SHOWN)
2895                return commit_ignore;
2896        if (revs->unpacked && has_sha1_pack(commit->object.sha1))
2897                return commit_ignore;
2898        if (revs->show_all)
2899                return commit_show;
2900        if (commit->object.flags & UNINTERESTING)
2901                return commit_ignore;
2902        if (revs->min_age != -1 && (commit->date > revs->min_age))
2903                return commit_ignore;
2904        if (revs->min_parents || (revs->max_parents >= 0)) {
2905                int n = commit_list_count(commit->parents);
2906                if ((n < revs->min_parents) ||
2907                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
2908                        return commit_ignore;
2909        }
2910        if (!commit_match(commit, revs))
2911                return commit_ignore;
2912        if (revs->prune && revs->dense) {
2913                /* Commit without changes? */
2914                if (commit->object.flags & TREESAME) {
2915                        int n;
2916                        struct commit_list *p;
2917                        /* drop merges unless we want parenthood */
2918                        if (!want_ancestry(revs))
2919                                return commit_ignore;
2920                        /*
2921                         * If we want ancestry, then need to keep any merges
2922                         * between relevant commits to tie together topology.
2923                         * For consistency with TREESAME and simplification
2924                         * use "relevant" here rather than just INTERESTING,
2925                         * to treat bottom commit(s) as part of the topology.
2926                         */
2927                        for (n = 0, p = commit->parents; p; p = p->next)
2928                                if (relevant_commit(p->item))
2929                                        if (++n >= 2)
2930                                                return commit_show;
2931                        return commit_ignore;
2932                }
2933        }
2934        return commit_show;
2935}
2936
2937define_commit_slab(saved_parents, struct commit_list *);
2938
2939#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
2940
2941/*
2942 * You may only call save_parents() once per commit (this is checked
2943 * for non-root commits).
2944 */
2945static void save_parents(struct rev_info *revs, struct commit *commit)
2946{
2947        struct commit_list **pp;
2948
2949        if (!revs->saved_parents_slab) {
2950                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
2951                init_saved_parents(revs->saved_parents_slab);
2952        }
2953
2954        pp = saved_parents_at(revs->saved_parents_slab, commit);
2955
2956        /*
2957         * When walking with reflogs, we may visit the same commit
2958         * several times: once for each appearance in the reflog.
2959         *
2960         * In this case, save_parents() will be called multiple times.
2961         * We want to keep only the first set of parents.  We need to
2962         * store a sentinel value for an empty (i.e., NULL) parent
2963         * list to distinguish it from a not-yet-saved list, however.
2964         */
2965        if (*pp)
2966                return;
2967        if (commit->parents)
2968                *pp = copy_commit_list(commit->parents);
2969        else
2970                *pp = EMPTY_PARENT_LIST;
2971}
2972
2973static void free_saved_parents(struct rev_info *revs)
2974{
2975        if (revs->saved_parents_slab)
2976                clear_saved_parents(revs->saved_parents_slab);
2977}
2978
2979struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
2980{
2981        struct commit_list *parents;
2982
2983        if (!revs->saved_parents_slab)
2984                return commit->parents;
2985
2986        parents = *saved_parents_at(revs->saved_parents_slab, commit);
2987        if (parents == EMPTY_PARENT_LIST)
2988                return NULL;
2989        return parents;
2990}
2991
2992enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
2993{
2994        enum commit_action action = get_commit_action(revs, commit);
2995
2996        if (action == commit_show &&
2997            !revs->show_all &&
2998            revs->prune && revs->dense && want_ancestry(revs)) {
2999                /*
3000                 * --full-diff on simplified parents is no good: it
3001                 * will show spurious changes from the commits that
3002                 * were elided.  So we save the parents on the side
3003                 * when --full-diff is in effect.
3004                 */
3005                if (revs->full_diff)
3006                        save_parents(revs, commit);
3007                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3008                        return commit_error;
3009        }
3010        return action;
3011}
3012
3013static void track_linear(struct rev_info *revs, struct commit *commit)
3014{
3015        if (revs->track_first_time) {
3016                revs->linear = 1;
3017                revs->track_first_time = 0;
3018        } else {
3019                struct commit_list *p;
3020                for (p = revs->previous_parents; p; p = p->next)
3021                        if (p->item == NULL || /* first commit */
3022                            !hashcmp(p->item->object.sha1, commit->object.sha1))
3023                                break;
3024                revs->linear = p != NULL;
3025        }
3026        if (revs->reverse) {
3027                if (revs->linear)
3028                        commit->object.flags |= TRACK_LINEAR;
3029        }
3030        free_commit_list(revs->previous_parents);
3031        revs->previous_parents = copy_commit_list(commit->parents);
3032}
3033
3034static struct commit *get_revision_1(struct rev_info *revs)
3035{
3036        if (!revs->commits)
3037                return NULL;
3038
3039        do {
3040                struct commit_list *entry = revs->commits;
3041                struct commit *commit = entry->item;
3042
3043                revs->commits = entry->next;
3044                free(entry);
3045
3046                if (revs->reflog_info) {
3047                        save_parents(revs, commit);
3048                        fake_reflog_parent(revs->reflog_info, commit);
3049                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3050                }
3051
3052                /*
3053                 * If we haven't done the list limiting, we need to look at
3054                 * the parents here. We also need to do the date-based limiting
3055                 * that we'd otherwise have done in limit_list().
3056                 */
3057                if (!revs->limited) {
3058                        if (revs->max_age != -1 &&
3059                            (commit->date < revs->max_age))
3060                                continue;
3061                        if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3062                                if (!revs->ignore_missing_links)
3063                                        die("Failed to traverse parents of commit %s",
3064                                                sha1_to_hex(commit->object.sha1));
3065                        }
3066                }
3067
3068                switch (simplify_commit(revs, commit)) {
3069                case commit_ignore:
3070                        continue;
3071                case commit_error:
3072                        die("Failed to simplify parents of commit %s",
3073                            sha1_to_hex(commit->object.sha1));
3074                default:
3075                        if (revs->track_linear)
3076                                track_linear(revs, commit);
3077                        return commit;
3078                }
3079        } while (revs->commits);
3080        return NULL;
3081}
3082
3083/*
3084 * Return true for entries that have not yet been shown.  (This is an
3085 * object_array_each_func_t.)
3086 */
3087static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3088{
3089        return !(entry->item->flags & SHOWN);
3090}
3091
3092/*
3093 * If array is on the verge of a realloc, garbage-collect any entries
3094 * that have already been shown to try to free up some space.
3095 */
3096static void gc_boundary(struct object_array *array)
3097{
3098        if (array->nr == array->alloc)
3099                object_array_filter(array, entry_unshown, NULL);
3100}
3101
3102static void create_boundary_commit_list(struct rev_info *revs)
3103{
3104        unsigned i;
3105        struct commit *c;
3106        struct object_array *array = &revs->boundary_commits;
3107        struct object_array_entry *objects = array->objects;
3108
3109        /*
3110         * If revs->commits is non-NULL at this point, an error occurred in
3111         * get_revision_1().  Ignore the error and continue printing the
3112         * boundary commits anyway.  (This is what the code has always
3113         * done.)
3114         */
3115        if (revs->commits) {
3116                free_commit_list(revs->commits);
3117                revs->commits = NULL;
3118        }
3119
3120        /*
3121         * Put all of the actual boundary commits from revs->boundary_commits
3122         * into revs->commits
3123         */
3124        for (i = 0; i < array->nr; i++) {
3125                c = (struct commit *)(objects[i].item);
3126                if (!c)
3127                        continue;
3128                if (!(c->object.flags & CHILD_SHOWN))
3129                        continue;
3130                if (c->object.flags & (SHOWN | BOUNDARY))
3131                        continue;
3132                c->object.flags |= BOUNDARY;
3133                commit_list_insert(c, &revs->commits);
3134        }
3135
3136        /*
3137         * If revs->topo_order is set, sort the boundary commits
3138         * in topological order
3139         */
3140        sort_in_topological_order(&revs->commits, revs->sort_order);
3141}
3142
3143static struct commit *get_revision_internal(struct rev_info *revs)
3144{
3145        struct commit *c = NULL;
3146        struct commit_list *l;
3147
3148        if (revs->boundary == 2) {
3149                /*
3150                 * All of the normal commits have already been returned,
3151                 * and we are now returning boundary commits.
3152                 * create_boundary_commit_list() has populated
3153                 * revs->commits with the remaining commits to return.
3154                 */
3155                c = pop_commit(&revs->commits);
3156                if (c)
3157                        c->object.flags |= SHOWN;
3158                return c;
3159        }
3160
3161        /*
3162         * If our max_count counter has reached zero, then we are done. We
3163         * don't simply return NULL because we still might need to show
3164         * boundary commits. But we want to avoid calling get_revision_1, which
3165         * might do a considerable amount of work finding the next commit only
3166         * for us to throw it away.
3167         *
3168         * If it is non-zero, then either we don't have a max_count at all
3169         * (-1), or it is still counting, in which case we decrement.
3170         */
3171        if (revs->max_count) {
3172                c = get_revision_1(revs);
3173                if (c) {
3174                        while (revs->skip_count > 0) {
3175                                revs->skip_count--;
3176                                c = get_revision_1(revs);
3177                                if (!c)
3178                                        break;
3179                        }
3180                }
3181
3182                if (revs->max_count > 0)
3183                        revs->max_count--;
3184        }
3185
3186        if (c)
3187                c->object.flags |= SHOWN;
3188
3189        if (!revs->boundary)
3190                return c;
3191
3192        if (!c) {
3193                /*
3194                 * get_revision_1() runs out the commits, and
3195                 * we are done computing the boundaries.
3196                 * switch to boundary commits output mode.
3197                 */
3198                revs->boundary = 2;
3199
3200                /*
3201                 * Update revs->commits to contain the list of
3202                 * boundary commits.
3203                 */
3204                create_boundary_commit_list(revs);
3205
3206                return get_revision_internal(revs);
3207        }
3208
3209        /*
3210         * boundary commits are the commits that are parents of the
3211         * ones we got from get_revision_1() but they themselves are
3212         * not returned from get_revision_1().  Before returning
3213         * 'c', we need to mark its parents that they could be boundaries.
3214         */
3215
3216        for (l = c->parents; l; l = l->next) {
3217                struct object *p;
3218                p = &(l->item->object);
3219                if (p->flags & (CHILD_SHOWN | SHOWN))
3220                        continue;
3221                p->flags |= CHILD_SHOWN;
3222                gc_boundary(&revs->boundary_commits);
3223                add_object_array(p, NULL, &revs->boundary_commits);
3224        }
3225
3226        return c;
3227}
3228
3229struct commit *get_revision(struct rev_info *revs)
3230{
3231        struct commit *c;
3232        struct commit_list *reversed;
3233
3234        if (revs->reverse) {
3235                reversed = NULL;
3236                while ((c = get_revision_internal(revs)))
3237                        commit_list_insert(c, &reversed);
3238                revs->commits = reversed;
3239                revs->reverse = 0;
3240                revs->reverse_output_stage = 1;
3241        }
3242
3243        if (revs->reverse_output_stage) {
3244                c = pop_commit(&revs->commits);
3245                if (revs->track_linear)
3246                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3247                return c;
3248        }
3249
3250        c = get_revision_internal(revs);
3251        if (c && revs->graph)
3252                graph_update(revs->graph, c);
3253        if (!c) {
3254                free_saved_parents(revs);
3255                if (revs->previous_parents) {
3256                        free_commit_list(revs->previous_parents);
3257                        revs->previous_parents = NULL;
3258                }
3259        }
3260        return c;
3261}
3262
3263char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3264{
3265        if (commit->object.flags & BOUNDARY)
3266                return "-";
3267        else if (commit->object.flags & UNINTERESTING)
3268                return "^";
3269        else if (commit->object.flags & PATCHSAME)
3270                return "=";
3271        else if (!revs || revs->left_right) {
3272                if (commit->object.flags & SYMMETRIC_LEFT)
3273                        return "<";
3274                else
3275                        return ">";
3276        } else if (revs->graph)
3277                return "*";
3278        else if (revs->cherry_mark)
3279                return "+";
3280        return "";
3281}
3282
3283void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3284{
3285        char *mark = get_revision_mark(revs, commit);
3286        if (!strlen(mark))
3287                return;
3288        fputs(mark, stdout);
3289        putchar(' ');
3290}