revision.con commit Merge branch 'jk/cvsimport-quoting' into maint-2.10 (6d6e2f8)
   1#include "cache.h"
   2#include "tag.h"
   3#include "blob.h"
   4#include "tree.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "refs.h"
   8#include "revision.h"
   9#include "graph.h"
  10#include "grep.h"
  11#include "reflog-walk.h"
  12#include "patch-ids.h"
  13#include "decorate.h"
  14#include "log-tree.h"
  15#include "string-list.h"
  16#include "line-log.h"
  17#include "mailmap.h"
  18#include "commit-slab.h"
  19#include "dir.h"
  20#include "cache-tree.h"
  21#include "bisect.h"
  22
  23volatile show_early_output_fn_t show_early_output;
  24
  25static const char *term_bad;
  26static const char *term_good;
  27
  28void show_object_with_name(FILE *out, struct object *obj, const char *name)
  29{
  30        const char *p;
  31
  32        fprintf(out, "%s ", oid_to_hex(&obj->oid));
  33        for (p = name; *p && *p != '\n'; p++)
  34                fputc(*p, out);
  35        fputc('\n', out);
  36}
  37
  38static void mark_blob_uninteresting(struct blob *blob)
  39{
  40        if (!blob)
  41                return;
  42        if (blob->object.flags & UNINTERESTING)
  43                return;
  44        blob->object.flags |= UNINTERESTING;
  45}
  46
  47static void mark_tree_contents_uninteresting(struct tree *tree)
  48{
  49        struct tree_desc desc;
  50        struct name_entry entry;
  51        struct object *obj = &tree->object;
  52
  53        if (!has_object_file(&obj->oid))
  54                return;
  55        if (parse_tree(tree) < 0)
  56                die("bad tree %s", oid_to_hex(&obj->oid));
  57
  58        init_tree_desc(&desc, tree->buffer, tree->size);
  59        while (tree_entry(&desc, &entry)) {
  60                switch (object_type(entry.mode)) {
  61                case OBJ_TREE:
  62                        mark_tree_uninteresting(lookup_tree(entry.oid->hash));
  63                        break;
  64                case OBJ_BLOB:
  65                        mark_blob_uninteresting(lookup_blob(entry.oid->hash));
  66                        break;
  67                default:
  68                        /* Subproject commit - not in this repository */
  69                        break;
  70                }
  71        }
  72
  73        /*
  74         * We don't care about the tree any more
  75         * after it has been marked uninteresting.
  76         */
  77        free_tree_buffer(tree);
  78}
  79
  80void mark_tree_uninteresting(struct tree *tree)
  81{
  82        struct object *obj;
  83
  84        if (!tree)
  85                return;
  86
  87        obj = &tree->object;
  88        if (obj->flags & UNINTERESTING)
  89                return;
  90        obj->flags |= UNINTERESTING;
  91        mark_tree_contents_uninteresting(tree);
  92}
  93
  94void mark_parents_uninteresting(struct commit *commit)
  95{
  96        struct commit_list *parents = NULL, *l;
  97
  98        for (l = commit->parents; l; l = l->next)
  99                commit_list_insert(l->item, &parents);
 100
 101        while (parents) {
 102                struct commit *commit = pop_commit(&parents);
 103
 104                while (commit) {
 105                        /*
 106                         * A missing commit is ok iff its parent is marked
 107                         * uninteresting.
 108                         *
 109                         * We just mark such a thing parsed, so that when
 110                         * it is popped next time around, we won't be trying
 111                         * to parse it and get an error.
 112                         */
 113                        if (!has_object_file(&commit->object.oid))
 114                                commit->object.parsed = 1;
 115
 116                        if (commit->object.flags & UNINTERESTING)
 117                                break;
 118
 119                        commit->object.flags |= UNINTERESTING;
 120
 121                        /*
 122                         * Normally we haven't parsed the parent
 123                         * yet, so we won't have a parent of a parent
 124                         * here. However, it may turn out that we've
 125                         * reached this commit some other way (where it
 126                         * wasn't uninteresting), in which case we need
 127                         * to mark its parents recursively too..
 128                         */
 129                        if (!commit->parents)
 130                                break;
 131
 132                        for (l = commit->parents->next; l; l = l->next)
 133                                commit_list_insert(l->item, &parents);
 134                        commit = commit->parents->item;
 135                }
 136        }
 137}
 138
 139static void add_pending_object_with_path(struct rev_info *revs,
 140                                         struct object *obj,
 141                                         const char *name, unsigned mode,
 142                                         const char *path)
 143{
 144        if (!obj)
 145                return;
 146        if (revs->no_walk && (obj->flags & UNINTERESTING))
 147                revs->no_walk = 0;
 148        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 149                struct strbuf buf = STRBUF_INIT;
 150                int len = interpret_branch_name(name, 0, &buf);
 151                int st;
 152
 153                if (0 < len && name[len] && buf.len)
 154                        strbuf_addstr(&buf, name + len);
 155                st = add_reflog_for_walk(revs->reflog_info,
 156                                         (struct commit *)obj,
 157                                         buf.buf[0] ? buf.buf: name);
 158                strbuf_release(&buf);
 159                if (st)
 160                        return;
 161        }
 162        add_object_array_with_path(obj, name, &revs->pending, mode, path);
 163}
 164
 165static void add_pending_object_with_mode(struct rev_info *revs,
 166                                         struct object *obj,
 167                                         const char *name, unsigned mode)
 168{
 169        add_pending_object_with_path(revs, obj, name, mode, NULL);
 170}
 171
 172void add_pending_object(struct rev_info *revs,
 173                        struct object *obj, const char *name)
 174{
 175        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 176}
 177
 178void add_head_to_pending(struct rev_info *revs)
 179{
 180        unsigned char sha1[20];
 181        struct object *obj;
 182        if (get_sha1("HEAD", sha1))
 183                return;
 184        obj = parse_object(sha1);
 185        if (!obj)
 186                return;
 187        add_pending_object(revs, obj, "HEAD");
 188}
 189
 190static struct object *get_reference(struct rev_info *revs, const char *name,
 191                                    const unsigned char *sha1,
 192                                    unsigned int flags)
 193{
 194        struct object *object;
 195
 196        object = parse_object(sha1);
 197        if (!object) {
 198                if (revs->ignore_missing)
 199                        return object;
 200                die("bad object %s", name);
 201        }
 202        object->flags |= flags;
 203        return object;
 204}
 205
 206void add_pending_sha1(struct rev_info *revs, const char *name,
 207                      const unsigned char *sha1, unsigned int flags)
 208{
 209        struct object *object = get_reference(revs, name, sha1, flags);
 210        add_pending_object(revs, object, name);
 211}
 212
 213static struct commit *handle_commit(struct rev_info *revs,
 214                                    struct object_array_entry *entry)
 215{
 216        struct object *object = entry->item;
 217        const char *name = entry->name;
 218        const char *path = entry->path;
 219        unsigned int mode = entry->mode;
 220        unsigned long flags = object->flags;
 221
 222        /*
 223         * Tag object? Look what it points to..
 224         */
 225        while (object->type == OBJ_TAG) {
 226                struct tag *tag = (struct tag *) object;
 227                if (revs->tag_objects && !(flags & UNINTERESTING))
 228                        add_pending_object(revs, object, tag->tag);
 229                if (!tag->tagged)
 230                        die("bad tag");
 231                object = parse_object(tag->tagged->oid.hash);
 232                if (!object) {
 233                        if (flags & UNINTERESTING)
 234                                return NULL;
 235                        die("bad object %s", oid_to_hex(&tag->tagged->oid));
 236                }
 237                object->flags |= flags;
 238                /*
 239                 * We'll handle the tagged object by looping or dropping
 240                 * through to the non-tag handlers below. Do not
 241                 * propagate path data from the tag's pending entry.
 242                 */
 243                path = NULL;
 244                mode = 0;
 245        }
 246
 247        /*
 248         * Commit object? Just return it, we'll do all the complex
 249         * reachability crud.
 250         */
 251        if (object->type == OBJ_COMMIT) {
 252                struct commit *commit = (struct commit *)object;
 253                if (parse_commit(commit) < 0)
 254                        die("unable to parse commit %s", name);
 255                if (flags & UNINTERESTING) {
 256                        mark_parents_uninteresting(commit);
 257                        revs->limited = 1;
 258                }
 259                if (revs->show_source && !commit->util)
 260                        commit->util = xstrdup(name);
 261                return commit;
 262        }
 263
 264        /*
 265         * Tree object? Either mark it uninteresting, or add it
 266         * to the list of objects to look at later..
 267         */
 268        if (object->type == OBJ_TREE) {
 269                struct tree *tree = (struct tree *)object;
 270                if (!revs->tree_objects)
 271                        return NULL;
 272                if (flags & UNINTERESTING) {
 273                        mark_tree_contents_uninteresting(tree);
 274                        return NULL;
 275                }
 276                add_pending_object_with_path(revs, object, name, mode, path);
 277                return NULL;
 278        }
 279
 280        /*
 281         * Blob object? You know the drill by now..
 282         */
 283        if (object->type == OBJ_BLOB) {
 284                if (!revs->blob_objects)
 285                        return NULL;
 286                if (flags & UNINTERESTING)
 287                        return NULL;
 288                add_pending_object_with_path(revs, object, name, mode, path);
 289                return NULL;
 290        }
 291        die("%s is unknown object", name);
 292}
 293
 294static int everybody_uninteresting(struct commit_list *orig,
 295                                   struct commit **interesting_cache)
 296{
 297        struct commit_list *list = orig;
 298
 299        if (*interesting_cache) {
 300                struct commit *commit = *interesting_cache;
 301                if (!(commit->object.flags & UNINTERESTING))
 302                        return 0;
 303        }
 304
 305        while (list) {
 306                struct commit *commit = list->item;
 307                list = list->next;
 308                if (commit->object.flags & UNINTERESTING)
 309                        continue;
 310
 311                *interesting_cache = commit;
 312                return 0;
 313        }
 314        return 1;
 315}
 316
 317/*
 318 * A definition of "relevant" commit that we can use to simplify limited graphs
 319 * by eliminating side branches.
 320 *
 321 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 322 * in our list), or that is a specified BOTTOM commit. Then after computing
 323 * a limited list, during processing we can generally ignore boundary merges
 324 * coming from outside the graph, (ie from irrelevant parents), and treat
 325 * those merges as if they were single-parent. TREESAME is defined to consider
 326 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 327 * we don't care if we were !TREESAME to non-graph parents.
 328 *
 329 * Treating bottom commits as relevant ensures that a limited graph's
 330 * connection to the actual bottom commit is not viewed as a side branch, but
 331 * treated as part of the graph. For example:
 332 *
 333 *   ....Z...A---X---o---o---B
 334 *        .     /
 335 *         W---Y
 336 *
 337 * When computing "A..B", the A-X connection is at least as important as
 338 * Y-X, despite A being flagged UNINTERESTING.
 339 *
 340 * And when computing --ancestry-path "A..B", the A-X connection is more
 341 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 342 */
 343static inline int relevant_commit(struct commit *commit)
 344{
 345        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 346}
 347
 348/*
 349 * Return a single relevant commit from a parent list. If we are a TREESAME
 350 * commit, and this selects one of our parents, then we can safely simplify to
 351 * that parent.
 352 */
 353static struct commit *one_relevant_parent(const struct rev_info *revs,
 354                                          struct commit_list *orig)
 355{
 356        struct commit_list *list = orig;
 357        struct commit *relevant = NULL;
 358
 359        if (!orig)
 360                return NULL;
 361
 362        /*
 363         * For 1-parent commits, or if first-parent-only, then return that
 364         * first parent (even if not "relevant" by the above definition).
 365         * TREESAME will have been set purely on that parent.
 366         */
 367        if (revs->first_parent_only || !orig->next)
 368                return orig->item;
 369
 370        /*
 371         * For multi-parent commits, identify a sole relevant parent, if any.
 372         * If we have only one relevant parent, then TREESAME will be set purely
 373         * with regard to that parent, and we can simplify accordingly.
 374         *
 375         * If we have more than one relevant parent, or no relevant parents
 376         * (and multiple irrelevant ones), then we can't select a parent here
 377         * and return NULL.
 378         */
 379        while (list) {
 380                struct commit *commit = list->item;
 381                list = list->next;
 382                if (relevant_commit(commit)) {
 383                        if (relevant)
 384                                return NULL;
 385                        relevant = commit;
 386                }
 387        }
 388        return relevant;
 389}
 390
 391/*
 392 * The goal is to get REV_TREE_NEW as the result only if the
 393 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 394 * if the whole diff is removal of old data, and otherwise
 395 * REV_TREE_DIFFERENT (of course if the trees are the same we
 396 * want REV_TREE_SAME).
 397 * That means that once we get to REV_TREE_DIFFERENT, we do not
 398 * have to look any further.
 399 */
 400static int tree_difference = REV_TREE_SAME;
 401
 402static void file_add_remove(struct diff_options *options,
 403                    int addremove, unsigned mode,
 404                    const unsigned char *sha1,
 405                    int sha1_valid,
 406                    const char *fullpath, unsigned dirty_submodule)
 407{
 408        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 409
 410        tree_difference |= diff;
 411        if (tree_difference == REV_TREE_DIFFERENT)
 412                DIFF_OPT_SET(options, HAS_CHANGES);
 413}
 414
 415static void file_change(struct diff_options *options,
 416                 unsigned old_mode, unsigned new_mode,
 417                 const unsigned char *old_sha1,
 418                 const unsigned char *new_sha1,
 419                 int old_sha1_valid, int new_sha1_valid,
 420                 const char *fullpath,
 421                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 422{
 423        tree_difference = REV_TREE_DIFFERENT;
 424        DIFF_OPT_SET(options, HAS_CHANGES);
 425}
 426
 427static int rev_compare_tree(struct rev_info *revs,
 428                            struct commit *parent, struct commit *commit)
 429{
 430        struct tree *t1 = parent->tree;
 431        struct tree *t2 = commit->tree;
 432
 433        if (!t1)
 434                return REV_TREE_NEW;
 435        if (!t2)
 436                return REV_TREE_OLD;
 437
 438        if (revs->simplify_by_decoration) {
 439                /*
 440                 * If we are simplifying by decoration, then the commit
 441                 * is worth showing if it has a tag pointing at it.
 442                 */
 443                if (get_name_decoration(&commit->object))
 444                        return REV_TREE_DIFFERENT;
 445                /*
 446                 * A commit that is not pointed by a tag is uninteresting
 447                 * if we are not limited by path.  This means that you will
 448                 * see the usual "commits that touch the paths" plus any
 449                 * tagged commit by specifying both --simplify-by-decoration
 450                 * and pathspec.
 451                 */
 452                if (!revs->prune_data.nr)
 453                        return REV_TREE_SAME;
 454        }
 455
 456        tree_difference = REV_TREE_SAME;
 457        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 458        if (diff_tree_sha1(t1->object.oid.hash, t2->object.oid.hash, "",
 459                           &revs->pruning) < 0)
 460                return REV_TREE_DIFFERENT;
 461        return tree_difference;
 462}
 463
 464static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 465{
 466        int retval;
 467        struct tree *t1 = commit->tree;
 468
 469        if (!t1)
 470                return 0;
 471
 472        tree_difference = REV_TREE_SAME;
 473        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 474        retval = diff_tree_sha1(NULL, t1->object.oid.hash, "", &revs->pruning);
 475
 476        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 477}
 478
 479struct treesame_state {
 480        unsigned int nparents;
 481        unsigned char treesame[FLEX_ARRAY];
 482};
 483
 484static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 485{
 486        unsigned n = commit_list_count(commit->parents);
 487        struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 488        st->nparents = n;
 489        add_decoration(&revs->treesame, &commit->object, st);
 490        return st;
 491}
 492
 493/*
 494 * Must be called immediately after removing the nth_parent from a commit's
 495 * parent list, if we are maintaining the per-parent treesame[] decoration.
 496 * This does not recalculate the master TREESAME flag - update_treesame()
 497 * should be called to update it after a sequence of treesame[] modifications
 498 * that may have affected it.
 499 */
 500static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 501{
 502        struct treesame_state *st;
 503        int old_same;
 504
 505        if (!commit->parents) {
 506                /*
 507                 * Have just removed the only parent from a non-merge.
 508                 * Different handling, as we lack decoration.
 509                 */
 510                if (nth_parent != 0)
 511                        die("compact_treesame %u", nth_parent);
 512                old_same = !!(commit->object.flags & TREESAME);
 513                if (rev_same_tree_as_empty(revs, commit))
 514                        commit->object.flags |= TREESAME;
 515                else
 516                        commit->object.flags &= ~TREESAME;
 517                return old_same;
 518        }
 519
 520        st = lookup_decoration(&revs->treesame, &commit->object);
 521        if (!st || nth_parent >= st->nparents)
 522                die("compact_treesame %u", nth_parent);
 523
 524        old_same = st->treesame[nth_parent];
 525        memmove(st->treesame + nth_parent,
 526                st->treesame + nth_parent + 1,
 527                st->nparents - nth_parent - 1);
 528
 529        /*
 530         * If we've just become a non-merge commit, update TREESAME
 531         * immediately, and remove the no-longer-needed decoration.
 532         * If still a merge, defer update until update_treesame().
 533         */
 534        if (--st->nparents == 1) {
 535                if (commit->parents->next)
 536                        die("compact_treesame parents mismatch");
 537                if (st->treesame[0] && revs->dense)
 538                        commit->object.flags |= TREESAME;
 539                else
 540                        commit->object.flags &= ~TREESAME;
 541                free(add_decoration(&revs->treesame, &commit->object, NULL));
 542        }
 543
 544        return old_same;
 545}
 546
 547static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 548{
 549        if (commit->parents && commit->parents->next) {
 550                unsigned n;
 551                struct treesame_state *st;
 552                struct commit_list *p;
 553                unsigned relevant_parents;
 554                unsigned relevant_change, irrelevant_change;
 555
 556                st = lookup_decoration(&revs->treesame, &commit->object);
 557                if (!st)
 558                        die("update_treesame %s", oid_to_hex(&commit->object.oid));
 559                relevant_parents = 0;
 560                relevant_change = irrelevant_change = 0;
 561                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 562                        if (relevant_commit(p->item)) {
 563                                relevant_change |= !st->treesame[n];
 564                                relevant_parents++;
 565                        } else
 566                                irrelevant_change |= !st->treesame[n];
 567                }
 568                if (relevant_parents ? relevant_change : irrelevant_change)
 569                        commit->object.flags &= ~TREESAME;
 570                else
 571                        commit->object.flags |= TREESAME;
 572        }
 573
 574        return commit->object.flags & TREESAME;
 575}
 576
 577static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 578{
 579        /*
 580         * TREESAME is irrelevant unless prune && dense;
 581         * if simplify_history is set, we can't have a mixture of TREESAME and
 582         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 583         *    decoration anyway);
 584         * if first_parent_only is set, then the TREESAME flag is locked
 585         *    against the first parent (and again we lack treesame[] decoration).
 586         */
 587        return revs->prune && revs->dense &&
 588               !revs->simplify_history &&
 589               !revs->first_parent_only;
 590}
 591
 592static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 593{
 594        struct commit_list **pp, *parent;
 595        struct treesame_state *ts = NULL;
 596        int relevant_change = 0, irrelevant_change = 0;
 597        int relevant_parents, nth_parent;
 598
 599        /*
 600         * If we don't do pruning, everything is interesting
 601         */
 602        if (!revs->prune)
 603                return;
 604
 605        if (!commit->tree)
 606                return;
 607
 608        if (!commit->parents) {
 609                if (rev_same_tree_as_empty(revs, commit))
 610                        commit->object.flags |= TREESAME;
 611                return;
 612        }
 613
 614        /*
 615         * Normal non-merge commit? If we don't want to make the
 616         * history dense, we consider it always to be a change..
 617         */
 618        if (!revs->dense && !commit->parents->next)
 619                return;
 620
 621        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 622             (parent = *pp) != NULL;
 623             pp = &parent->next, nth_parent++) {
 624                struct commit *p = parent->item;
 625                if (relevant_commit(p))
 626                        relevant_parents++;
 627
 628                if (nth_parent == 1) {
 629                        /*
 630                         * This our second loop iteration - so we now know
 631                         * we're dealing with a merge.
 632                         *
 633                         * Do not compare with later parents when we care only about
 634                         * the first parent chain, in order to avoid derailing the
 635                         * traversal to follow a side branch that brought everything
 636                         * in the path we are limited to by the pathspec.
 637                         */
 638                        if (revs->first_parent_only)
 639                                break;
 640                        /*
 641                         * If this will remain a potentially-simplifiable
 642                         * merge, remember per-parent treesame if needed.
 643                         * Initialise the array with the comparison from our
 644                         * first iteration.
 645                         */
 646                        if (revs->treesame.name &&
 647                            !revs->simplify_history &&
 648                            !(commit->object.flags & UNINTERESTING)) {
 649                                ts = initialise_treesame(revs, commit);
 650                                if (!(irrelevant_change || relevant_change))
 651                                        ts->treesame[0] = 1;
 652                        }
 653                }
 654                if (parse_commit(p) < 0)
 655                        die("cannot simplify commit %s (because of %s)",
 656                            oid_to_hex(&commit->object.oid),
 657                            oid_to_hex(&p->object.oid));
 658                switch (rev_compare_tree(revs, p, commit)) {
 659                case REV_TREE_SAME:
 660                        if (!revs->simplify_history || !relevant_commit(p)) {
 661                                /* Even if a merge with an uninteresting
 662                                 * side branch brought the entire change
 663                                 * we are interested in, we do not want
 664                                 * to lose the other branches of this
 665                                 * merge, so we just keep going.
 666                                 */
 667                                if (ts)
 668                                        ts->treesame[nth_parent] = 1;
 669                                continue;
 670                        }
 671                        parent->next = NULL;
 672                        commit->parents = parent;
 673                        commit->object.flags |= TREESAME;
 674                        return;
 675
 676                case REV_TREE_NEW:
 677                        if (revs->remove_empty_trees &&
 678                            rev_same_tree_as_empty(revs, p)) {
 679                                /* We are adding all the specified
 680                                 * paths from this parent, so the
 681                                 * history beyond this parent is not
 682                                 * interesting.  Remove its parents
 683                                 * (they are grandparents for us).
 684                                 * IOW, we pretend this parent is a
 685                                 * "root" commit.
 686                                 */
 687                                if (parse_commit(p) < 0)
 688                                        die("cannot simplify commit %s (invalid %s)",
 689                                            oid_to_hex(&commit->object.oid),
 690                                            oid_to_hex(&p->object.oid));
 691                                p->parents = NULL;
 692                        }
 693                /* fallthrough */
 694                case REV_TREE_OLD:
 695                case REV_TREE_DIFFERENT:
 696                        if (relevant_commit(p))
 697                                relevant_change = 1;
 698                        else
 699                                irrelevant_change = 1;
 700                        continue;
 701                }
 702                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
 703        }
 704
 705        /*
 706         * TREESAME is straightforward for single-parent commits. For merge
 707         * commits, it is most useful to define it so that "irrelevant"
 708         * parents cannot make us !TREESAME - if we have any relevant
 709         * parents, then we only consider TREESAMEness with respect to them,
 710         * allowing irrelevant merges from uninteresting branches to be
 711         * simplified away. Only if we have only irrelevant parents do we
 712         * base TREESAME on them. Note that this logic is replicated in
 713         * update_treesame, which should be kept in sync.
 714         */
 715        if (relevant_parents ? !relevant_change : !irrelevant_change)
 716                commit->object.flags |= TREESAME;
 717}
 718
 719static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 720                    struct commit_list *cached_base, struct commit_list **cache)
 721{
 722        struct commit_list *new_entry;
 723
 724        if (cached_base && p->date < cached_base->item->date)
 725                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 726        else
 727                new_entry = commit_list_insert_by_date(p, head);
 728
 729        if (cache && (!*cache || p->date < (*cache)->item->date))
 730                *cache = new_entry;
 731}
 732
 733static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 734                    struct commit_list **list, struct commit_list **cache_ptr)
 735{
 736        struct commit_list *parent = commit->parents;
 737        unsigned left_flag;
 738        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 739
 740        if (commit->object.flags & ADDED)
 741                return 0;
 742        commit->object.flags |= ADDED;
 743
 744        if (revs->include_check &&
 745            !revs->include_check(commit, revs->include_check_data))
 746                return 0;
 747
 748        /*
 749         * If the commit is uninteresting, don't try to
 750         * prune parents - we want the maximal uninteresting
 751         * set.
 752         *
 753         * Normally we haven't parsed the parent
 754         * yet, so we won't have a parent of a parent
 755         * here. However, it may turn out that we've
 756         * reached this commit some other way (where it
 757         * wasn't uninteresting), in which case we need
 758         * to mark its parents recursively too..
 759         */
 760        if (commit->object.flags & UNINTERESTING) {
 761                while (parent) {
 762                        struct commit *p = parent->item;
 763                        parent = parent->next;
 764                        if (p)
 765                                p->object.flags |= UNINTERESTING;
 766                        if (parse_commit_gently(p, 1) < 0)
 767                                continue;
 768                        if (p->parents)
 769                                mark_parents_uninteresting(p);
 770                        if (p->object.flags & SEEN)
 771                                continue;
 772                        p->object.flags |= SEEN;
 773                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 774                }
 775                return 0;
 776        }
 777
 778        /*
 779         * Ok, the commit wasn't uninteresting. Try to
 780         * simplify the commit history and find the parent
 781         * that has no differences in the path set if one exists.
 782         */
 783        try_to_simplify_commit(revs, commit);
 784
 785        if (revs->no_walk)
 786                return 0;
 787
 788        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 789
 790        for (parent = commit->parents; parent; parent = parent->next) {
 791                struct commit *p = parent->item;
 792
 793                if (parse_commit_gently(p, revs->ignore_missing_links) < 0)
 794                        return -1;
 795                if (revs->show_source && !p->util)
 796                        p->util = commit->util;
 797                p->object.flags |= left_flag;
 798                if (!(p->object.flags & SEEN)) {
 799                        p->object.flags |= SEEN;
 800                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 801                }
 802                if (revs->first_parent_only)
 803                        break;
 804        }
 805        return 0;
 806}
 807
 808static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 809{
 810        struct commit_list *p;
 811        int left_count = 0, right_count = 0;
 812        int left_first;
 813        struct patch_ids ids;
 814        unsigned cherry_flag;
 815
 816        /* First count the commits on the left and on the right */
 817        for (p = list; p; p = p->next) {
 818                struct commit *commit = p->item;
 819                unsigned flags = commit->object.flags;
 820                if (flags & BOUNDARY)
 821                        ;
 822                else if (flags & SYMMETRIC_LEFT)
 823                        left_count++;
 824                else
 825                        right_count++;
 826        }
 827
 828        if (!left_count || !right_count)
 829                return;
 830
 831        left_first = left_count < right_count;
 832        init_patch_ids(&ids);
 833        ids.diffopts.pathspec = revs->diffopt.pathspec;
 834
 835        /* Compute patch-ids for one side */
 836        for (p = list; p; p = p->next) {
 837                struct commit *commit = p->item;
 838                unsigned flags = commit->object.flags;
 839
 840                if (flags & BOUNDARY)
 841                        continue;
 842                /*
 843                 * If we have fewer left, left_first is set and we omit
 844                 * commits on the right branch in this loop.  If we have
 845                 * fewer right, we skip the left ones.
 846                 */
 847                if (left_first != !!(flags & SYMMETRIC_LEFT))
 848                        continue;
 849                add_commit_patch_id(commit, &ids);
 850        }
 851
 852        /* either cherry_mark or cherry_pick are true */
 853        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 854
 855        /* Check the other side */
 856        for (p = list; p; p = p->next) {
 857                struct commit *commit = p->item;
 858                struct patch_id *id;
 859                unsigned flags = commit->object.flags;
 860
 861                if (flags & BOUNDARY)
 862                        continue;
 863                /*
 864                 * If we have fewer left, left_first is set and we omit
 865                 * commits on the left branch in this loop.
 866                 */
 867                if (left_first == !!(flags & SYMMETRIC_LEFT))
 868                        continue;
 869
 870                /*
 871                 * Have we seen the same patch id?
 872                 */
 873                id = has_commit_patch_id(commit, &ids);
 874                if (!id)
 875                        continue;
 876
 877                commit->object.flags |= cherry_flag;
 878                id->commit->object.flags |= cherry_flag;
 879        }
 880
 881        free_patch_ids(&ids);
 882}
 883
 884/* How many extra uninteresting commits we want to see.. */
 885#define SLOP 5
 886
 887static int still_interesting(struct commit_list *src, unsigned long date, int slop,
 888                             struct commit **interesting_cache)
 889{
 890        /*
 891         * No source list at all? We're definitely done..
 892         */
 893        if (!src)
 894                return 0;
 895
 896        /*
 897         * Does the destination list contain entries with a date
 898         * before the source list? Definitely _not_ done.
 899         */
 900        if (date <= src->item->date)
 901                return SLOP;
 902
 903        /*
 904         * Does the source list still have interesting commits in
 905         * it? Definitely not done..
 906         */
 907        if (!everybody_uninteresting(src, interesting_cache))
 908                return SLOP;
 909
 910        /* Ok, we're closing in.. */
 911        return slop-1;
 912}
 913
 914/*
 915 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 916 * of B but not ancestors of A but further limits the result to those
 917 * that are descendants of A.  This takes the list of bottom commits and
 918 * the result of "A..B" without --ancestry-path, and limits the latter
 919 * further to the ones that can reach one of the commits in "bottom".
 920 */
 921static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 922{
 923        struct commit_list *p;
 924        struct commit_list *rlist = NULL;
 925        int made_progress;
 926
 927        /*
 928         * Reverse the list so that it will be likely that we would
 929         * process parents before children.
 930         */
 931        for (p = list; p; p = p->next)
 932                commit_list_insert(p->item, &rlist);
 933
 934        for (p = bottom; p; p = p->next)
 935                p->item->object.flags |= TMP_MARK;
 936
 937        /*
 938         * Mark the ones that can reach bottom commits in "list",
 939         * in a bottom-up fashion.
 940         */
 941        do {
 942                made_progress = 0;
 943                for (p = rlist; p; p = p->next) {
 944                        struct commit *c = p->item;
 945                        struct commit_list *parents;
 946                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 947                                continue;
 948                        for (parents = c->parents;
 949                             parents;
 950                             parents = parents->next) {
 951                                if (!(parents->item->object.flags & TMP_MARK))
 952                                        continue;
 953                                c->object.flags |= TMP_MARK;
 954                                made_progress = 1;
 955                                break;
 956                        }
 957                }
 958        } while (made_progress);
 959
 960        /*
 961         * NEEDSWORK: decide if we want to remove parents that are
 962         * not marked with TMP_MARK from commit->parents for commits
 963         * in the resulting list.  We may not want to do that, though.
 964         */
 965
 966        /*
 967         * The ones that are not marked with TMP_MARK are uninteresting
 968         */
 969        for (p = list; p; p = p->next) {
 970                struct commit *c = p->item;
 971                if (c->object.flags & TMP_MARK)
 972                        continue;
 973                c->object.flags |= UNINTERESTING;
 974        }
 975
 976        /* We are done with the TMP_MARK */
 977        for (p = list; p; p = p->next)
 978                p->item->object.flags &= ~TMP_MARK;
 979        for (p = bottom; p; p = p->next)
 980                p->item->object.flags &= ~TMP_MARK;
 981        free_commit_list(rlist);
 982}
 983
 984/*
 985 * Before walking the history, keep the set of "negative" refs the
 986 * caller has asked to exclude.
 987 *
 988 * This is used to compute "rev-list --ancestry-path A..B", as we need
 989 * to filter the result of "A..B" further to the ones that can actually
 990 * reach A.
 991 */
 992static struct commit_list *collect_bottom_commits(struct commit_list *list)
 993{
 994        struct commit_list *elem, *bottom = NULL;
 995        for (elem = list; elem; elem = elem->next)
 996                if (elem->item->object.flags & BOTTOM)
 997                        commit_list_insert(elem->item, &bottom);
 998        return bottom;
 999}
1000
1001/* Assumes either left_only or right_only is set */
1002static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1003{
1004        struct commit_list *p;
1005
1006        for (p = list; p; p = p->next) {
1007                struct commit *commit = p->item;
1008
1009                if (revs->right_only) {
1010                        if (commit->object.flags & SYMMETRIC_LEFT)
1011                                commit->object.flags |= SHOWN;
1012                } else  /* revs->left_only is set */
1013                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1014                                commit->object.flags |= SHOWN;
1015        }
1016}
1017
1018static int limit_list(struct rev_info *revs)
1019{
1020        int slop = SLOP;
1021        unsigned long date = ~0ul;
1022        struct commit_list *list = revs->commits;
1023        struct commit_list *newlist = NULL;
1024        struct commit_list **p = &newlist;
1025        struct commit_list *bottom = NULL;
1026        struct commit *interesting_cache = NULL;
1027
1028        if (revs->ancestry_path) {
1029                bottom = collect_bottom_commits(list);
1030                if (!bottom)
1031                        die("--ancestry-path given but there are no bottom commits");
1032        }
1033
1034        while (list) {
1035                struct commit *commit = pop_commit(&list);
1036                struct object *obj = &commit->object;
1037                show_early_output_fn_t show;
1038
1039                if (commit == interesting_cache)
1040                        interesting_cache = NULL;
1041
1042                if (revs->max_age != -1 && (commit->date < revs->max_age))
1043                        obj->flags |= UNINTERESTING;
1044                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1045                        return -1;
1046                if (obj->flags & UNINTERESTING) {
1047                        mark_parents_uninteresting(commit);
1048                        if (revs->show_all)
1049                                p = &commit_list_insert(commit, p)->next;
1050                        slop = still_interesting(list, date, slop, &interesting_cache);
1051                        if (slop)
1052                                continue;
1053                        /* If showing all, add the whole pending list to the end */
1054                        if (revs->show_all)
1055                                *p = list;
1056                        break;
1057                }
1058                if (revs->min_age != -1 && (commit->date > revs->min_age))
1059                        continue;
1060                date = commit->date;
1061                p = &commit_list_insert(commit, p)->next;
1062
1063                show = show_early_output;
1064                if (!show)
1065                        continue;
1066
1067                show(revs, newlist);
1068                show_early_output = NULL;
1069        }
1070        if (revs->cherry_pick || revs->cherry_mark)
1071                cherry_pick_list(newlist, revs);
1072
1073        if (revs->left_only || revs->right_only)
1074                limit_left_right(newlist, revs);
1075
1076        if (bottom) {
1077                limit_to_ancestry(bottom, newlist);
1078                free_commit_list(bottom);
1079        }
1080
1081        /*
1082         * Check if any commits have become TREESAME by some of their parents
1083         * becoming UNINTERESTING.
1084         */
1085        if (limiting_can_increase_treesame(revs))
1086                for (list = newlist; list; list = list->next) {
1087                        struct commit *c = list->item;
1088                        if (c->object.flags & (UNINTERESTING | TREESAME))
1089                                continue;
1090                        update_treesame(revs, c);
1091                }
1092
1093        revs->commits = newlist;
1094        return 0;
1095}
1096
1097/*
1098 * Add an entry to refs->cmdline with the specified information.
1099 * *name is copied.
1100 */
1101static void add_rev_cmdline(struct rev_info *revs,
1102                            struct object *item,
1103                            const char *name,
1104                            int whence,
1105                            unsigned flags)
1106{
1107        struct rev_cmdline_info *info = &revs->cmdline;
1108        int nr = info->nr;
1109
1110        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1111        info->rev[nr].item = item;
1112        info->rev[nr].name = xstrdup(name);
1113        info->rev[nr].whence = whence;
1114        info->rev[nr].flags = flags;
1115        info->nr++;
1116}
1117
1118static void add_rev_cmdline_list(struct rev_info *revs,
1119                                 struct commit_list *commit_list,
1120                                 int whence,
1121                                 unsigned flags)
1122{
1123        while (commit_list) {
1124                struct object *object = &commit_list->item->object;
1125                add_rev_cmdline(revs, object, oid_to_hex(&object->oid),
1126                                whence, flags);
1127                commit_list = commit_list->next;
1128        }
1129}
1130
1131struct all_refs_cb {
1132        int all_flags;
1133        int warned_bad_reflog;
1134        struct rev_info *all_revs;
1135        const char *name_for_errormsg;
1136};
1137
1138int ref_excluded(struct string_list *ref_excludes, const char *path)
1139{
1140        struct string_list_item *item;
1141
1142        if (!ref_excludes)
1143                return 0;
1144        for_each_string_list_item(item, ref_excludes) {
1145                if (!wildmatch(item->string, path, 0, NULL))
1146                        return 1;
1147        }
1148        return 0;
1149}
1150
1151static int handle_one_ref(const char *path, const struct object_id *oid,
1152                          int flag, void *cb_data)
1153{
1154        struct all_refs_cb *cb = cb_data;
1155        struct object *object;
1156
1157        if (ref_excluded(cb->all_revs->ref_excludes, path))
1158            return 0;
1159
1160        object = get_reference(cb->all_revs, path, oid->hash, cb->all_flags);
1161        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1162        add_pending_sha1(cb->all_revs, path, oid->hash, cb->all_flags);
1163        return 0;
1164}
1165
1166static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1167        unsigned flags)
1168{
1169        cb->all_revs = revs;
1170        cb->all_flags = flags;
1171}
1172
1173void clear_ref_exclusion(struct string_list **ref_excludes_p)
1174{
1175        if (*ref_excludes_p) {
1176                string_list_clear(*ref_excludes_p, 0);
1177                free(*ref_excludes_p);
1178        }
1179        *ref_excludes_p = NULL;
1180}
1181
1182void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1183{
1184        if (!*ref_excludes_p) {
1185                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1186                (*ref_excludes_p)->strdup_strings = 1;
1187        }
1188        string_list_append(*ref_excludes_p, exclude);
1189}
1190
1191static void handle_refs(const char *submodule, struct rev_info *revs, unsigned flags,
1192                int (*for_each)(const char *, each_ref_fn, void *))
1193{
1194        struct all_refs_cb cb;
1195        init_all_refs_cb(&cb, revs, flags);
1196        for_each(submodule, handle_one_ref, &cb);
1197}
1198
1199static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
1200{
1201        struct all_refs_cb *cb = cb_data;
1202        if (!is_null_sha1(sha1)) {
1203                struct object *o = parse_object(sha1);
1204                if (o) {
1205                        o->flags |= cb->all_flags;
1206                        /* ??? CMDLINEFLAGS ??? */
1207                        add_pending_object(cb->all_revs, o, "");
1208                }
1209                else if (!cb->warned_bad_reflog) {
1210                        warning("reflog of '%s' references pruned commits",
1211                                cb->name_for_errormsg);
1212                        cb->warned_bad_reflog = 1;
1213                }
1214        }
1215}
1216
1217static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
1218                const char *email, unsigned long timestamp, int tz,
1219                const char *message, void *cb_data)
1220{
1221        handle_one_reflog_commit(osha1, cb_data);
1222        handle_one_reflog_commit(nsha1, cb_data);
1223        return 0;
1224}
1225
1226static int handle_one_reflog(const char *path, const struct object_id *oid,
1227                             int flag, void *cb_data)
1228{
1229        struct all_refs_cb *cb = cb_data;
1230        cb->warned_bad_reflog = 0;
1231        cb->name_for_errormsg = path;
1232        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
1233        return 0;
1234}
1235
1236void add_reflogs_to_pending(struct rev_info *revs, unsigned flags)
1237{
1238        struct all_refs_cb cb;
1239
1240        cb.all_revs = revs;
1241        cb.all_flags = flags;
1242        for_each_reflog(handle_one_reflog, &cb);
1243}
1244
1245static void add_cache_tree(struct cache_tree *it, struct rev_info *revs,
1246                           struct strbuf *path)
1247{
1248        size_t baselen = path->len;
1249        int i;
1250
1251        if (it->entry_count >= 0) {
1252                struct tree *tree = lookup_tree(it->sha1);
1253                add_pending_object_with_path(revs, &tree->object, "",
1254                                             040000, path->buf);
1255        }
1256
1257        for (i = 0; i < it->subtree_nr; i++) {
1258                struct cache_tree_sub *sub = it->down[i];
1259                strbuf_addf(path, "%s%s", baselen ? "/" : "", sub->name);
1260                add_cache_tree(sub->cache_tree, revs, path);
1261                strbuf_setlen(path, baselen);
1262        }
1263
1264}
1265
1266void add_index_objects_to_pending(struct rev_info *revs, unsigned flags)
1267{
1268        int i;
1269
1270        read_cache();
1271        for (i = 0; i < active_nr; i++) {
1272                struct cache_entry *ce = active_cache[i];
1273                struct blob *blob;
1274
1275                if (S_ISGITLINK(ce->ce_mode))
1276                        continue;
1277
1278                blob = lookup_blob(ce->sha1);
1279                if (!blob)
1280                        die("unable to add index blob to traversal");
1281                add_pending_object_with_path(revs, &blob->object, "",
1282                                             ce->ce_mode, ce->name);
1283        }
1284
1285        if (active_cache_tree) {
1286                struct strbuf path = STRBUF_INIT;
1287                add_cache_tree(active_cache_tree, revs, &path);
1288                strbuf_release(&path);
1289        }
1290}
1291
1292static int add_parents_only(struct rev_info *revs, const char *arg_, int flags)
1293{
1294        unsigned char sha1[20];
1295        struct object *it;
1296        struct commit *commit;
1297        struct commit_list *parents;
1298        const char *arg = arg_;
1299
1300        if (*arg == '^') {
1301                flags ^= UNINTERESTING | BOTTOM;
1302                arg++;
1303        }
1304        if (get_sha1_committish(arg, sha1))
1305                return 0;
1306        while (1) {
1307                it = get_reference(revs, arg, sha1, 0);
1308                if (!it && revs->ignore_missing)
1309                        return 0;
1310                if (it->type != OBJ_TAG)
1311                        break;
1312                if (!((struct tag*)it)->tagged)
1313                        return 0;
1314                hashcpy(sha1, ((struct tag*)it)->tagged->oid.hash);
1315        }
1316        if (it->type != OBJ_COMMIT)
1317                return 0;
1318        commit = (struct commit *)it;
1319        for (parents = commit->parents; parents; parents = parents->next) {
1320                it = &parents->item->object;
1321                it->flags |= flags;
1322                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1323                add_pending_object(revs, it, arg);
1324        }
1325        return 1;
1326}
1327
1328void init_revisions(struct rev_info *revs, const char *prefix)
1329{
1330        memset(revs, 0, sizeof(*revs));
1331
1332        revs->abbrev = DEFAULT_ABBREV;
1333        revs->ignore_merges = 1;
1334        revs->simplify_history = 1;
1335        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
1336        DIFF_OPT_SET(&revs->pruning, QUICK);
1337        revs->pruning.add_remove = file_add_remove;
1338        revs->pruning.change = file_change;
1339        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1340        revs->dense = 1;
1341        revs->prefix = prefix;
1342        revs->max_age = -1;
1343        revs->min_age = -1;
1344        revs->skip_count = -1;
1345        revs->max_count = -1;
1346        revs->max_parents = -1;
1347        revs->expand_tabs_in_log = -1;
1348
1349        revs->commit_format = CMIT_FMT_DEFAULT;
1350        revs->expand_tabs_in_log_default = 8;
1351
1352        init_grep_defaults();
1353        grep_init(&revs->grep_filter, prefix);
1354        revs->grep_filter.status_only = 1;
1355        revs->grep_filter.regflags = REG_NEWLINE;
1356
1357        diff_setup(&revs->diffopt);
1358        if (prefix && !revs->diffopt.prefix) {
1359                revs->diffopt.prefix = prefix;
1360                revs->diffopt.prefix_length = strlen(prefix);
1361        }
1362
1363        revs->notes_opt.use_default_notes = -1;
1364}
1365
1366static void add_pending_commit_list(struct rev_info *revs,
1367                                    struct commit_list *commit_list,
1368                                    unsigned int flags)
1369{
1370        while (commit_list) {
1371                struct object *object = &commit_list->item->object;
1372                object->flags |= flags;
1373                add_pending_object(revs, object, oid_to_hex(&object->oid));
1374                commit_list = commit_list->next;
1375        }
1376}
1377
1378static void prepare_show_merge(struct rev_info *revs)
1379{
1380        struct commit_list *bases;
1381        struct commit *head, *other;
1382        unsigned char sha1[20];
1383        const char **prune = NULL;
1384        int i, prune_num = 1; /* counting terminating NULL */
1385
1386        if (get_sha1("HEAD", sha1))
1387                die("--merge without HEAD?");
1388        head = lookup_commit_or_die(sha1, "HEAD");
1389        if (get_sha1("MERGE_HEAD", sha1))
1390                die("--merge without MERGE_HEAD?");
1391        other = lookup_commit_or_die(sha1, "MERGE_HEAD");
1392        add_pending_object(revs, &head->object, "HEAD");
1393        add_pending_object(revs, &other->object, "MERGE_HEAD");
1394        bases = get_merge_bases(head, other);
1395        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1396        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1397        free_commit_list(bases);
1398        head->object.flags |= SYMMETRIC_LEFT;
1399
1400        if (!active_nr)
1401                read_cache();
1402        for (i = 0; i < active_nr; i++) {
1403                const struct cache_entry *ce = active_cache[i];
1404                if (!ce_stage(ce))
1405                        continue;
1406                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1407                        prune_num++;
1408                        REALLOC_ARRAY(prune, prune_num);
1409                        prune[prune_num-2] = ce->name;
1410                        prune[prune_num-1] = NULL;
1411                }
1412                while ((i+1 < active_nr) &&
1413                       ce_same_name(ce, active_cache[i+1]))
1414                        i++;
1415        }
1416        clear_pathspec(&revs->prune_data);
1417        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1418                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1419        revs->limited = 1;
1420}
1421
1422int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1423{
1424        struct object_context oc;
1425        char *dotdot;
1426        struct object *object;
1427        unsigned char sha1[20];
1428        int local_flags;
1429        const char *arg = arg_;
1430        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1431        unsigned get_sha1_flags = 0;
1432
1433        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1434
1435        dotdot = strstr(arg, "..");
1436        if (dotdot) {
1437                unsigned char from_sha1[20];
1438                const char *next = dotdot + 2;
1439                const char *this = arg;
1440                int symmetric = *next == '.';
1441                unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1442                static const char head_by_default[] = "HEAD";
1443                unsigned int a_flags;
1444
1445                *dotdot = 0;
1446                next += symmetric;
1447
1448                if (!*next)
1449                        next = head_by_default;
1450                if (dotdot == arg)
1451                        this = head_by_default;
1452                if (this == head_by_default && next == head_by_default &&
1453                    !symmetric) {
1454                        /*
1455                         * Just ".."?  That is not a range but the
1456                         * pathspec for the parent directory.
1457                         */
1458                        if (!cant_be_filename) {
1459                                *dotdot = '.';
1460                                return -1;
1461                        }
1462                }
1463                if (!get_sha1_committish(this, from_sha1) &&
1464                    !get_sha1_committish(next, sha1)) {
1465                        struct object *a_obj, *b_obj;
1466
1467                        if (!cant_be_filename) {
1468                                *dotdot = '.';
1469                                verify_non_filename(revs->prefix, arg);
1470                        }
1471
1472                        a_obj = parse_object(from_sha1);
1473                        b_obj = parse_object(sha1);
1474                        if (!a_obj || !b_obj) {
1475                        missing:
1476                                if (revs->ignore_missing)
1477                                        return 0;
1478                                die(symmetric
1479                                    ? "Invalid symmetric difference expression %s"
1480                                    : "Invalid revision range %s", arg);
1481                        }
1482
1483                        if (!symmetric) {
1484                                /* just A..B */
1485                                a_flags = flags_exclude;
1486                        } else {
1487                                /* A...B -- find merge bases between the two */
1488                                struct commit *a, *b;
1489                                struct commit_list *exclude;
1490
1491                                a = (a_obj->type == OBJ_COMMIT
1492                                     ? (struct commit *)a_obj
1493                                     : lookup_commit_reference(a_obj->oid.hash));
1494                                b = (b_obj->type == OBJ_COMMIT
1495                                     ? (struct commit *)b_obj
1496                                     : lookup_commit_reference(b_obj->oid.hash));
1497                                if (!a || !b)
1498                                        goto missing;
1499                                exclude = get_merge_bases(a, b);
1500                                add_rev_cmdline_list(revs, exclude,
1501                                                     REV_CMD_MERGE_BASE,
1502                                                     flags_exclude);
1503                                add_pending_commit_list(revs, exclude,
1504                                                        flags_exclude);
1505                                free_commit_list(exclude);
1506
1507                                a_flags = flags | SYMMETRIC_LEFT;
1508                        }
1509
1510                        a_obj->flags |= a_flags;
1511                        b_obj->flags |= flags;
1512                        add_rev_cmdline(revs, a_obj, this,
1513                                        REV_CMD_LEFT, a_flags);
1514                        add_rev_cmdline(revs, b_obj, next,
1515                                        REV_CMD_RIGHT, flags);
1516                        add_pending_object(revs, a_obj, this);
1517                        add_pending_object(revs, b_obj, next);
1518                        return 0;
1519                }
1520                *dotdot = '.';
1521        }
1522        dotdot = strstr(arg, "^@");
1523        if (dotdot && !dotdot[2]) {
1524                *dotdot = 0;
1525                if (add_parents_only(revs, arg, flags))
1526                        return 0;
1527                *dotdot = '^';
1528        }
1529        dotdot = strstr(arg, "^!");
1530        if (dotdot && !dotdot[2]) {
1531                *dotdot = 0;
1532                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM)))
1533                        *dotdot = '^';
1534        }
1535
1536        local_flags = 0;
1537        if (*arg == '^') {
1538                local_flags = UNINTERESTING | BOTTOM;
1539                arg++;
1540        }
1541
1542        if (revarg_opt & REVARG_COMMITTISH)
1543                get_sha1_flags = GET_SHA1_COMMITTISH;
1544
1545        if (get_sha1_with_context(arg, get_sha1_flags, sha1, &oc))
1546                return revs->ignore_missing ? 0 : -1;
1547        if (!cant_be_filename)
1548                verify_non_filename(revs->prefix, arg);
1549        object = get_reference(revs, arg, sha1, flags ^ local_flags);
1550        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1551        add_pending_object_with_mode(revs, object, arg, oc.mode);
1552        return 0;
1553}
1554
1555struct cmdline_pathspec {
1556        int alloc;
1557        int nr;
1558        const char **path;
1559};
1560
1561static void append_prune_data(struct cmdline_pathspec *prune, const char **av)
1562{
1563        while (*av) {
1564                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1565                prune->path[prune->nr++] = *(av++);
1566        }
1567}
1568
1569static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1570                                     struct cmdline_pathspec *prune)
1571{
1572        while (strbuf_getline(sb, stdin) != EOF) {
1573                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1574                prune->path[prune->nr++] = xstrdup(sb->buf);
1575        }
1576}
1577
1578static void read_revisions_from_stdin(struct rev_info *revs,
1579                                      struct cmdline_pathspec *prune)
1580{
1581        struct strbuf sb;
1582        int seen_dashdash = 0;
1583        int save_warning;
1584
1585        save_warning = warn_on_object_refname_ambiguity;
1586        warn_on_object_refname_ambiguity = 0;
1587
1588        strbuf_init(&sb, 1000);
1589        while (strbuf_getline(&sb, stdin) != EOF) {
1590                int len = sb.len;
1591                if (!len)
1592                        break;
1593                if (sb.buf[0] == '-') {
1594                        if (len == 2 && sb.buf[1] == '-') {
1595                                seen_dashdash = 1;
1596                                break;
1597                        }
1598                        die("options not supported in --stdin mode");
1599                }
1600                if (handle_revision_arg(sb.buf, revs, 0,
1601                                        REVARG_CANNOT_BE_FILENAME))
1602                        die("bad revision '%s'", sb.buf);
1603        }
1604        if (seen_dashdash)
1605                read_pathspec_from_stdin(revs, &sb, prune);
1606
1607        strbuf_release(&sb);
1608        warn_on_object_refname_ambiguity = save_warning;
1609}
1610
1611static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1612{
1613        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1614}
1615
1616static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1617{
1618        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1619}
1620
1621static void add_message_grep(struct rev_info *revs, const char *pattern)
1622{
1623        add_grep(revs, pattern, GREP_PATTERN_BODY);
1624}
1625
1626static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1627                               int *unkc, const char **unkv)
1628{
1629        const char *arg = argv[0];
1630        const char *optarg;
1631        int argcount;
1632
1633        /* pseudo revision arguments */
1634        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1635            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1636            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1637            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1638            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1639            !strcmp(arg, "--indexed-objects") ||
1640            starts_with(arg, "--exclude=") ||
1641            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1642            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1643        {
1644                unkv[(*unkc)++] = arg;
1645                return 1;
1646        }
1647
1648        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1649                revs->max_count = atoi(optarg);
1650                revs->no_walk = 0;
1651                return argcount;
1652        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1653                revs->skip_count = atoi(optarg);
1654                return argcount;
1655        } else if ((*arg == '-') && isdigit(arg[1])) {
1656                /* accept -<digit>, like traditional "head" */
1657                if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
1658                    revs->max_count < 0)
1659                        die("'%s': not a non-negative integer", arg + 1);
1660                revs->no_walk = 0;
1661        } else if (!strcmp(arg, "-n")) {
1662                if (argc <= 1)
1663                        return error("-n requires an argument");
1664                revs->max_count = atoi(argv[1]);
1665                revs->no_walk = 0;
1666                return 2;
1667        } else if (starts_with(arg, "-n")) {
1668                revs->max_count = atoi(arg + 2);
1669                revs->no_walk = 0;
1670        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1671                revs->max_age = atoi(optarg);
1672                return argcount;
1673        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1674                revs->max_age = approxidate(optarg);
1675                return argcount;
1676        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1677                revs->max_age = approxidate(optarg);
1678                return argcount;
1679        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1680                revs->min_age = atoi(optarg);
1681                return argcount;
1682        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1683                revs->min_age = approxidate(optarg);
1684                return argcount;
1685        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1686                revs->min_age = approxidate(optarg);
1687                return argcount;
1688        } else if (!strcmp(arg, "--first-parent")) {
1689                revs->first_parent_only = 1;
1690        } else if (!strcmp(arg, "--ancestry-path")) {
1691                revs->ancestry_path = 1;
1692                revs->simplify_history = 0;
1693                revs->limited = 1;
1694        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1695                init_reflog_walk(&revs->reflog_info);
1696        } else if (!strcmp(arg, "--default")) {
1697                if (argc <= 1)
1698                        return error("bad --default argument");
1699                revs->def = argv[1];
1700                return 2;
1701        } else if (!strcmp(arg, "--merge")) {
1702                revs->show_merge = 1;
1703        } else if (!strcmp(arg, "--topo-order")) {
1704                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1705                revs->topo_order = 1;
1706        } else if (!strcmp(arg, "--simplify-merges")) {
1707                revs->simplify_merges = 1;
1708                revs->topo_order = 1;
1709                revs->rewrite_parents = 1;
1710                revs->simplify_history = 0;
1711                revs->limited = 1;
1712        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1713                revs->simplify_merges = 1;
1714                revs->topo_order = 1;
1715                revs->rewrite_parents = 1;
1716                revs->simplify_history = 0;
1717                revs->simplify_by_decoration = 1;
1718                revs->limited = 1;
1719                revs->prune = 1;
1720                load_ref_decorations(DECORATE_SHORT_REFS);
1721        } else if (!strcmp(arg, "--date-order")) {
1722                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1723                revs->topo_order = 1;
1724        } else if (!strcmp(arg, "--author-date-order")) {
1725                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1726                revs->topo_order = 1;
1727        } else if (starts_with(arg, "--early-output")) {
1728                int count = 100;
1729                switch (arg[14]) {
1730                case '=':
1731                        count = atoi(arg+15);
1732                        /* Fallthrough */
1733                case 0:
1734                        revs->topo_order = 1;
1735                       revs->early_output = count;
1736                }
1737        } else if (!strcmp(arg, "--parents")) {
1738                revs->rewrite_parents = 1;
1739                revs->print_parents = 1;
1740        } else if (!strcmp(arg, "--dense")) {
1741                revs->dense = 1;
1742        } else if (!strcmp(arg, "--sparse")) {
1743                revs->dense = 0;
1744        } else if (!strcmp(arg, "--show-all")) {
1745                revs->show_all = 1;
1746        } else if (!strcmp(arg, "--remove-empty")) {
1747                revs->remove_empty_trees = 1;
1748        } else if (!strcmp(arg, "--merges")) {
1749                revs->min_parents = 2;
1750        } else if (!strcmp(arg, "--no-merges")) {
1751                revs->max_parents = 1;
1752        } else if (starts_with(arg, "--min-parents=")) {
1753                revs->min_parents = atoi(arg+14);
1754        } else if (starts_with(arg, "--no-min-parents")) {
1755                revs->min_parents = 0;
1756        } else if (starts_with(arg, "--max-parents=")) {
1757                revs->max_parents = atoi(arg+14);
1758        } else if (starts_with(arg, "--no-max-parents")) {
1759                revs->max_parents = -1;
1760        } else if (!strcmp(arg, "--boundary")) {
1761                revs->boundary = 1;
1762        } else if (!strcmp(arg, "--left-right")) {
1763                revs->left_right = 1;
1764        } else if (!strcmp(arg, "--left-only")) {
1765                if (revs->right_only)
1766                        die("--left-only is incompatible with --right-only"
1767                            " or --cherry");
1768                revs->left_only = 1;
1769        } else if (!strcmp(arg, "--right-only")) {
1770                if (revs->left_only)
1771                        die("--right-only is incompatible with --left-only");
1772                revs->right_only = 1;
1773        } else if (!strcmp(arg, "--cherry")) {
1774                if (revs->left_only)
1775                        die("--cherry is incompatible with --left-only");
1776                revs->cherry_mark = 1;
1777                revs->right_only = 1;
1778                revs->max_parents = 1;
1779                revs->limited = 1;
1780        } else if (!strcmp(arg, "--count")) {
1781                revs->count = 1;
1782        } else if (!strcmp(arg, "--cherry-mark")) {
1783                if (revs->cherry_pick)
1784                        die("--cherry-mark is incompatible with --cherry-pick");
1785                revs->cherry_mark = 1;
1786                revs->limited = 1; /* needs limit_list() */
1787        } else if (!strcmp(arg, "--cherry-pick")) {
1788                if (revs->cherry_mark)
1789                        die("--cherry-pick is incompatible with --cherry-mark");
1790                revs->cherry_pick = 1;
1791                revs->limited = 1;
1792        } else if (!strcmp(arg, "--objects")) {
1793                revs->tag_objects = 1;
1794                revs->tree_objects = 1;
1795                revs->blob_objects = 1;
1796        } else if (!strcmp(arg, "--objects-edge")) {
1797                revs->tag_objects = 1;
1798                revs->tree_objects = 1;
1799                revs->blob_objects = 1;
1800                revs->edge_hint = 1;
1801        } else if (!strcmp(arg, "--objects-edge-aggressive")) {
1802                revs->tag_objects = 1;
1803                revs->tree_objects = 1;
1804                revs->blob_objects = 1;
1805                revs->edge_hint = 1;
1806                revs->edge_hint_aggressive = 1;
1807        } else if (!strcmp(arg, "--verify-objects")) {
1808                revs->tag_objects = 1;
1809                revs->tree_objects = 1;
1810                revs->blob_objects = 1;
1811                revs->verify_objects = 1;
1812        } else if (!strcmp(arg, "--unpacked")) {
1813                revs->unpacked = 1;
1814        } else if (starts_with(arg, "--unpacked=")) {
1815                die("--unpacked=<packfile> no longer supported.");
1816        } else if (!strcmp(arg, "-r")) {
1817                revs->diff = 1;
1818                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1819        } else if (!strcmp(arg, "-t")) {
1820                revs->diff = 1;
1821                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1822                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1823        } else if (!strcmp(arg, "-m")) {
1824                revs->ignore_merges = 0;
1825        } else if (!strcmp(arg, "-c")) {
1826                revs->diff = 1;
1827                revs->dense_combined_merges = 0;
1828                revs->combine_merges = 1;
1829        } else if (!strcmp(arg, "--cc")) {
1830                revs->diff = 1;
1831                revs->dense_combined_merges = 1;
1832                revs->combine_merges = 1;
1833        } else if (!strcmp(arg, "-v")) {
1834                revs->verbose_header = 1;
1835        } else if (!strcmp(arg, "--pretty")) {
1836                revs->verbose_header = 1;
1837                revs->pretty_given = 1;
1838                get_commit_format(NULL, revs);
1839        } else if (starts_with(arg, "--pretty=") || starts_with(arg, "--format=")) {
1840                /*
1841                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1842                 * not allowed, since the argument is optional.
1843                 */
1844                revs->verbose_header = 1;
1845                revs->pretty_given = 1;
1846                get_commit_format(arg+9, revs);
1847        } else if (!strcmp(arg, "--expand-tabs")) {
1848                revs->expand_tabs_in_log = 8;
1849        } else if (!strcmp(arg, "--no-expand-tabs")) {
1850                revs->expand_tabs_in_log = 0;
1851        } else if (skip_prefix(arg, "--expand-tabs=", &arg)) {
1852                int val;
1853                if (strtol_i(arg, 10, &val) < 0 || val < 0)
1854                        die("'%s': not a non-negative integer", arg);
1855                revs->expand_tabs_in_log = val;
1856        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1857                revs->show_notes = 1;
1858                revs->show_notes_given = 1;
1859                revs->notes_opt.use_default_notes = 1;
1860        } else if (!strcmp(arg, "--show-signature")) {
1861                revs->show_signature = 1;
1862        } else if (!strcmp(arg, "--no-show-signature")) {
1863                revs->show_signature = 0;
1864        } else if (!strcmp(arg, "--show-linear-break") ||
1865                   starts_with(arg, "--show-linear-break=")) {
1866                if (starts_with(arg, "--show-linear-break="))
1867                        revs->break_bar = xstrdup(arg + 20);
1868                else
1869                        revs->break_bar = "                    ..........";
1870                revs->track_linear = 1;
1871                revs->track_first_time = 1;
1872        } else if (starts_with(arg, "--show-notes=") ||
1873                   starts_with(arg, "--notes=")) {
1874                struct strbuf buf = STRBUF_INIT;
1875                revs->show_notes = 1;
1876                revs->show_notes_given = 1;
1877                if (starts_with(arg, "--show-notes")) {
1878                        if (revs->notes_opt.use_default_notes < 0)
1879                                revs->notes_opt.use_default_notes = 1;
1880                        strbuf_addstr(&buf, arg+13);
1881                }
1882                else
1883                        strbuf_addstr(&buf, arg+8);
1884                expand_notes_ref(&buf);
1885                string_list_append(&revs->notes_opt.extra_notes_refs,
1886                                   strbuf_detach(&buf, NULL));
1887        } else if (!strcmp(arg, "--no-notes")) {
1888                revs->show_notes = 0;
1889                revs->show_notes_given = 1;
1890                revs->notes_opt.use_default_notes = -1;
1891                /* we have been strdup'ing ourselves, so trick
1892                 * string_list into free()ing strings */
1893                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
1894                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
1895                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
1896        } else if (!strcmp(arg, "--standard-notes")) {
1897                revs->show_notes_given = 1;
1898                revs->notes_opt.use_default_notes = 1;
1899        } else if (!strcmp(arg, "--no-standard-notes")) {
1900                revs->notes_opt.use_default_notes = 0;
1901        } else if (!strcmp(arg, "--oneline")) {
1902                revs->verbose_header = 1;
1903                get_commit_format("oneline", revs);
1904                revs->pretty_given = 1;
1905                revs->abbrev_commit = 1;
1906        } else if (!strcmp(arg, "--graph")) {
1907                revs->topo_order = 1;
1908                revs->rewrite_parents = 1;
1909                revs->graph = graph_init(revs);
1910        } else if (!strcmp(arg, "--root")) {
1911                revs->show_root_diff = 1;
1912        } else if (!strcmp(arg, "--no-commit-id")) {
1913                revs->no_commit_id = 1;
1914        } else if (!strcmp(arg, "--always")) {
1915                revs->always_show_header = 1;
1916        } else if (!strcmp(arg, "--no-abbrev")) {
1917                revs->abbrev = 0;
1918        } else if (!strcmp(arg, "--abbrev")) {
1919                revs->abbrev = DEFAULT_ABBREV;
1920        } else if (starts_with(arg, "--abbrev=")) {
1921                revs->abbrev = strtoul(arg + 9, NULL, 10);
1922                if (revs->abbrev < MINIMUM_ABBREV)
1923                        revs->abbrev = MINIMUM_ABBREV;
1924                else if (revs->abbrev > 40)
1925                        revs->abbrev = 40;
1926        } else if (!strcmp(arg, "--abbrev-commit")) {
1927                revs->abbrev_commit = 1;
1928                revs->abbrev_commit_given = 1;
1929        } else if (!strcmp(arg, "--no-abbrev-commit")) {
1930                revs->abbrev_commit = 0;
1931        } else if (!strcmp(arg, "--full-diff")) {
1932                revs->diff = 1;
1933                revs->full_diff = 1;
1934        } else if (!strcmp(arg, "--full-history")) {
1935                revs->simplify_history = 0;
1936        } else if (!strcmp(arg, "--relative-date")) {
1937                revs->date_mode.type = DATE_RELATIVE;
1938                revs->date_mode_explicit = 1;
1939        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
1940                parse_date_format(optarg, &revs->date_mode);
1941                revs->date_mode_explicit = 1;
1942                return argcount;
1943        } else if (!strcmp(arg, "--log-size")) {
1944                revs->show_log_size = 1;
1945        }
1946        /*
1947         * Grepping the commit log
1948         */
1949        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
1950                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
1951                return argcount;
1952        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
1953                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
1954                return argcount;
1955        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
1956                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
1957                return argcount;
1958        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
1959                add_message_grep(revs, optarg);
1960                return argcount;
1961        } else if (!strcmp(arg, "--grep-debug")) {
1962                revs->grep_filter.debug = 1;
1963        } else if (!strcmp(arg, "--basic-regexp")) {
1964                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_BRE;
1965        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
1966                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_ERE;
1967        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
1968                revs->grep_filter.regflags |= REG_ICASE;
1969                DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
1970        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
1971                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
1972        } else if (!strcmp(arg, "--perl-regexp")) {
1973                revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
1974        } else if (!strcmp(arg, "--all-match")) {
1975                revs->grep_filter.all_match = 1;
1976        } else if (!strcmp(arg, "--invert-grep")) {
1977                revs->invert_grep = 1;
1978        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
1979                if (strcmp(optarg, "none"))
1980                        git_log_output_encoding = xstrdup(optarg);
1981                else
1982                        git_log_output_encoding = "";
1983                return argcount;
1984        } else if (!strcmp(arg, "--reverse")) {
1985                revs->reverse ^= 1;
1986        } else if (!strcmp(arg, "--children")) {
1987                revs->children.name = "children";
1988                revs->limited = 1;
1989        } else if (!strcmp(arg, "--ignore-missing")) {
1990                revs->ignore_missing = 1;
1991        } else {
1992                int opts = diff_opt_parse(&revs->diffopt, argv, argc, revs->prefix);
1993                if (!opts)
1994                        unkv[(*unkc)++] = arg;
1995                return opts;
1996        }
1997        if (revs->graph && revs->track_linear)
1998                die("--show-linear-break and --graph are incompatible");
1999
2000        return 1;
2001}
2002
2003void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
2004                        const struct option *options,
2005                        const char * const usagestr[])
2006{
2007        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
2008                                    &ctx->cpidx, ctx->out);
2009        if (n <= 0) {
2010                error("unknown option `%s'", ctx->argv[0]);
2011                usage_with_options(usagestr, options);
2012        }
2013        ctx->argv += n;
2014        ctx->argc -= n;
2015}
2016
2017static int for_each_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data, const char *term) {
2018        struct strbuf bisect_refs = STRBUF_INIT;
2019        int status;
2020        strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
2021        status = for_each_ref_in_submodule(submodule, bisect_refs.buf, fn, cb_data);
2022        strbuf_release(&bisect_refs);
2023        return status;
2024}
2025
2026static int for_each_bad_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
2027{
2028        return for_each_bisect_ref(submodule, fn, cb_data, term_bad);
2029}
2030
2031static int for_each_good_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
2032{
2033        return for_each_bisect_ref(submodule, fn, cb_data, term_good);
2034}
2035
2036static int handle_revision_pseudo_opt(const char *submodule,
2037                                struct rev_info *revs,
2038                                int argc, const char **argv, int *flags)
2039{
2040        const char *arg = argv[0];
2041        const char *optarg;
2042        int argcount;
2043
2044        /*
2045         * NOTE!
2046         *
2047         * Commands like "git shortlog" will not accept the options below
2048         * unless parse_revision_opt queues them (as opposed to erroring
2049         * out).
2050         *
2051         * When implementing your new pseudo-option, remember to
2052         * register it in the list at the top of handle_revision_opt.
2053         */
2054        if (!strcmp(arg, "--all")) {
2055                handle_refs(submodule, revs, *flags, for_each_ref_submodule);
2056                handle_refs(submodule, revs, *flags, head_ref_submodule);
2057                clear_ref_exclusion(&revs->ref_excludes);
2058        } else if (!strcmp(arg, "--branches")) {
2059                handle_refs(submodule, revs, *flags, for_each_branch_ref_submodule);
2060                clear_ref_exclusion(&revs->ref_excludes);
2061        } else if (!strcmp(arg, "--bisect")) {
2062                read_bisect_terms(&term_bad, &term_good);
2063                handle_refs(submodule, revs, *flags, for_each_bad_bisect_ref);
2064                handle_refs(submodule, revs, *flags ^ (UNINTERESTING | BOTTOM), for_each_good_bisect_ref);
2065                revs->bisect = 1;
2066        } else if (!strcmp(arg, "--tags")) {
2067                handle_refs(submodule, revs, *flags, for_each_tag_ref_submodule);
2068                clear_ref_exclusion(&revs->ref_excludes);
2069        } else if (!strcmp(arg, "--remotes")) {
2070                handle_refs(submodule, revs, *flags, for_each_remote_ref_submodule);
2071                clear_ref_exclusion(&revs->ref_excludes);
2072        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2073                struct all_refs_cb cb;
2074                init_all_refs_cb(&cb, revs, *flags);
2075                for_each_glob_ref(handle_one_ref, optarg, &cb);
2076                clear_ref_exclusion(&revs->ref_excludes);
2077                return argcount;
2078        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2079                add_ref_exclusion(&revs->ref_excludes, optarg);
2080                return argcount;
2081        } else if (starts_with(arg, "--branches=")) {
2082                struct all_refs_cb cb;
2083                init_all_refs_cb(&cb, revs, *flags);
2084                for_each_glob_ref_in(handle_one_ref, arg + 11, "refs/heads/", &cb);
2085                clear_ref_exclusion(&revs->ref_excludes);
2086        } else if (starts_with(arg, "--tags=")) {
2087                struct all_refs_cb cb;
2088                init_all_refs_cb(&cb, revs, *flags);
2089                for_each_glob_ref_in(handle_one_ref, arg + 7, "refs/tags/", &cb);
2090                clear_ref_exclusion(&revs->ref_excludes);
2091        } else if (starts_with(arg, "--remotes=")) {
2092                struct all_refs_cb cb;
2093                init_all_refs_cb(&cb, revs, *flags);
2094                for_each_glob_ref_in(handle_one_ref, arg + 10, "refs/remotes/", &cb);
2095                clear_ref_exclusion(&revs->ref_excludes);
2096        } else if (!strcmp(arg, "--reflog")) {
2097                add_reflogs_to_pending(revs, *flags);
2098        } else if (!strcmp(arg, "--indexed-objects")) {
2099                add_index_objects_to_pending(revs, *flags);
2100        } else if (!strcmp(arg, "--not")) {
2101                *flags ^= UNINTERESTING | BOTTOM;
2102        } else if (!strcmp(arg, "--no-walk")) {
2103                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2104        } else if (starts_with(arg, "--no-walk=")) {
2105                /*
2106                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2107                 * not allowed, since the argument is optional.
2108                 */
2109                if (!strcmp(arg + 10, "sorted"))
2110                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2111                else if (!strcmp(arg + 10, "unsorted"))
2112                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2113                else
2114                        return error("invalid argument to --no-walk");
2115        } else if (!strcmp(arg, "--do-walk")) {
2116                revs->no_walk = 0;
2117        } else {
2118                return 0;
2119        }
2120
2121        return 1;
2122}
2123
2124static void NORETURN diagnose_missing_default(const char *def)
2125{
2126        unsigned char sha1[20];
2127        int flags;
2128        const char *refname;
2129
2130        refname = resolve_ref_unsafe(def, 0, sha1, &flags);
2131        if (!refname || !(flags & REF_ISSYMREF) || (flags & REF_ISBROKEN))
2132                die(_("your current branch appears to be broken"));
2133
2134        skip_prefix(refname, "refs/heads/", &refname);
2135        die(_("your current branch '%s' does not have any commits yet"),
2136            refname);
2137}
2138
2139/*
2140 * Parse revision information, filling in the "rev_info" structure,
2141 * and removing the used arguments from the argument list.
2142 *
2143 * Returns the number of arguments left that weren't recognized
2144 * (which are also moved to the head of the argument list)
2145 */
2146int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2147{
2148        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2149        struct cmdline_pathspec prune_data;
2150        const char *submodule = NULL;
2151
2152        memset(&prune_data, 0, sizeof(prune_data));
2153        if (opt)
2154                submodule = opt->submodule;
2155
2156        /* First, search for "--" */
2157        if (opt && opt->assume_dashdash) {
2158                seen_dashdash = 1;
2159        } else {
2160                seen_dashdash = 0;
2161                for (i = 1; i < argc; i++) {
2162                        const char *arg = argv[i];
2163                        if (strcmp(arg, "--"))
2164                                continue;
2165                        argv[i] = NULL;
2166                        argc = i;
2167                        if (argv[i + 1])
2168                                append_prune_data(&prune_data, argv + i + 1);
2169                        seen_dashdash = 1;
2170                        break;
2171                }
2172        }
2173
2174        /* Second, deal with arguments and options */
2175        flags = 0;
2176        revarg_opt = opt ? opt->revarg_opt : 0;
2177        if (seen_dashdash)
2178                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2179        read_from_stdin = 0;
2180        for (left = i = 1; i < argc; i++) {
2181                const char *arg = argv[i];
2182                if (*arg == '-') {
2183                        int opts;
2184
2185                        opts = handle_revision_pseudo_opt(submodule,
2186                                                revs, argc - i, argv + i,
2187                                                &flags);
2188                        if (opts > 0) {
2189                                i += opts - 1;
2190                                continue;
2191                        }
2192
2193                        if (!strcmp(arg, "--stdin")) {
2194                                if (revs->disable_stdin) {
2195                                        argv[left++] = arg;
2196                                        continue;
2197                                }
2198                                if (read_from_stdin++)
2199                                        die("--stdin given twice?");
2200                                read_revisions_from_stdin(revs, &prune_data);
2201                                continue;
2202                        }
2203
2204                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2205                        if (opts > 0) {
2206                                i += opts - 1;
2207                                continue;
2208                        }
2209                        if (opts < 0)
2210                                exit(128);
2211                        continue;
2212                }
2213
2214
2215                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2216                        int j;
2217                        if (seen_dashdash || *arg == '^')
2218                                die("bad revision '%s'", arg);
2219
2220                        /* If we didn't have a "--":
2221                         * (1) all filenames must exist;
2222                         * (2) all rev-args must not be interpretable
2223                         *     as a valid filename.
2224                         * but the latter we have checked in the main loop.
2225                         */
2226                        for (j = i; j < argc; j++)
2227                                verify_filename(revs->prefix, argv[j], j == i);
2228
2229                        append_prune_data(&prune_data, argv + i);
2230                        break;
2231                }
2232                else
2233                        got_rev_arg = 1;
2234        }
2235
2236        if (prune_data.nr) {
2237                /*
2238                 * If we need to introduce the magic "a lone ':' means no
2239                 * pathspec whatsoever", here is the place to do so.
2240                 *
2241                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2242                 *      prune_data.nr = 0;
2243                 *      prune_data.alloc = 0;
2244                 *      free(prune_data.path);
2245                 *      prune_data.path = NULL;
2246                 * } else {
2247                 *      terminate prune_data.alloc with NULL and
2248                 *      call init_pathspec() to set revs->prune_data here.
2249                 * }
2250                 */
2251                ALLOC_GROW(prune_data.path, prune_data.nr + 1, prune_data.alloc);
2252                prune_data.path[prune_data.nr++] = NULL;
2253                parse_pathspec(&revs->prune_data, 0, 0,
2254                               revs->prefix, prune_data.path);
2255        }
2256
2257        if (revs->def == NULL)
2258                revs->def = opt ? opt->def : NULL;
2259        if (opt && opt->tweak)
2260                opt->tweak(revs, opt);
2261        if (revs->show_merge)
2262                prepare_show_merge(revs);
2263        if (revs->def && !revs->pending.nr && !got_rev_arg) {
2264                unsigned char sha1[20];
2265                struct object *object;
2266                struct object_context oc;
2267                if (get_sha1_with_context(revs->def, 0, sha1, &oc))
2268                        diagnose_missing_default(revs->def);
2269                object = get_reference(revs, revs->def, sha1, 0);
2270                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2271        }
2272
2273        /* Did the user ask for any diff output? Run the diff! */
2274        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2275                revs->diff = 1;
2276
2277        /* Pickaxe, diff-filter and rename following need diffs */
2278        if (revs->diffopt.pickaxe ||
2279            revs->diffopt.filter ||
2280            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2281                revs->diff = 1;
2282
2283        if (revs->topo_order)
2284                revs->limited = 1;
2285
2286        if (revs->prune_data.nr) {
2287                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2288                /* Can't prune commits with rename following: the paths change.. */
2289                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2290                        revs->prune = 1;
2291                if (!revs->full_diff)
2292                        copy_pathspec(&revs->diffopt.pathspec,
2293                                      &revs->prune_data);
2294        }
2295        if (revs->combine_merges)
2296                revs->ignore_merges = 0;
2297        revs->diffopt.abbrev = revs->abbrev;
2298
2299        if (revs->line_level_traverse) {
2300                revs->limited = 1;
2301                revs->topo_order = 1;
2302        }
2303
2304        diff_setup_done(&revs->diffopt);
2305
2306        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2307                                 &revs->grep_filter);
2308        compile_grep_patterns(&revs->grep_filter);
2309
2310        if (revs->reverse && revs->reflog_info)
2311                die("cannot combine --reverse with --walk-reflogs");
2312        if (revs->rewrite_parents && revs->children.name)
2313                die("cannot combine --parents and --children");
2314
2315        /*
2316         * Limitations on the graph functionality
2317         */
2318        if (revs->reverse && revs->graph)
2319                die("cannot combine --reverse with --graph");
2320
2321        if (revs->reflog_info && revs->graph)
2322                die("cannot combine --walk-reflogs with --graph");
2323        if (revs->no_walk && revs->graph)
2324                die("cannot combine --no-walk with --graph");
2325        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2326                die("cannot use --grep-reflog without --walk-reflogs");
2327
2328        if (revs->first_parent_only && revs->bisect)
2329                die(_("--first-parent is incompatible with --bisect"));
2330
2331        if (revs->expand_tabs_in_log < 0)
2332                revs->expand_tabs_in_log = revs->expand_tabs_in_log_default;
2333
2334        return left;
2335}
2336
2337static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2338{
2339        struct commit_list *l = xcalloc(1, sizeof(*l));
2340
2341        l->item = child;
2342        l->next = add_decoration(&revs->children, &parent->object, l);
2343}
2344
2345static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2346{
2347        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2348        struct commit_list **pp, *p;
2349        int surviving_parents;
2350
2351        /* Examine existing parents while marking ones we have seen... */
2352        pp = &commit->parents;
2353        surviving_parents = 0;
2354        while ((p = *pp) != NULL) {
2355                struct commit *parent = p->item;
2356                if (parent->object.flags & TMP_MARK) {
2357                        *pp = p->next;
2358                        if (ts)
2359                                compact_treesame(revs, commit, surviving_parents);
2360                        continue;
2361                }
2362                parent->object.flags |= TMP_MARK;
2363                surviving_parents++;
2364                pp = &p->next;
2365        }
2366        /* clear the temporary mark */
2367        for (p = commit->parents; p; p = p->next) {
2368                p->item->object.flags &= ~TMP_MARK;
2369        }
2370        /* no update_treesame() - removing duplicates can't affect TREESAME */
2371        return surviving_parents;
2372}
2373
2374struct merge_simplify_state {
2375        struct commit *simplified;
2376};
2377
2378static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2379{
2380        struct merge_simplify_state *st;
2381
2382        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2383        if (!st) {
2384                st = xcalloc(1, sizeof(*st));
2385                add_decoration(&revs->merge_simplification, &commit->object, st);
2386        }
2387        return st;
2388}
2389
2390static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2391{
2392        struct commit_list *h = reduce_heads(commit->parents);
2393        int i = 0, marked = 0;
2394        struct commit_list *po, *pn;
2395
2396        /* Want these for sanity-checking only */
2397        int orig_cnt = commit_list_count(commit->parents);
2398        int cnt = commit_list_count(h);
2399
2400        /*
2401         * Not ready to remove items yet, just mark them for now, based
2402         * on the output of reduce_heads(). reduce_heads outputs the reduced
2403         * set in its original order, so this isn't too hard.
2404         */
2405        po = commit->parents;
2406        pn = h;
2407        while (po) {
2408                if (pn && po->item == pn->item) {
2409                        pn = pn->next;
2410                        i++;
2411                } else {
2412                        po->item->object.flags |= TMP_MARK;
2413                        marked++;
2414                }
2415                po=po->next;
2416        }
2417
2418        if (i != cnt || cnt+marked != orig_cnt)
2419                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2420
2421        free_commit_list(h);
2422
2423        return marked;
2424}
2425
2426static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2427{
2428        struct commit_list *p;
2429        int marked = 0;
2430
2431        for (p = commit->parents; p; p = p->next) {
2432                struct commit *parent = p->item;
2433                if (!parent->parents && (parent->object.flags & TREESAME)) {
2434                        parent->object.flags |= TMP_MARK;
2435                        marked++;
2436                }
2437        }
2438
2439        return marked;
2440}
2441
2442/*
2443 * Awkward naming - this means one parent we are TREESAME to.
2444 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2445 * empty tree). Better name suggestions?
2446 */
2447static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2448{
2449        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2450        struct commit *unmarked = NULL, *marked = NULL;
2451        struct commit_list *p;
2452        unsigned n;
2453
2454        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2455                if (ts->treesame[n]) {
2456                        if (p->item->object.flags & TMP_MARK) {
2457                                if (!marked)
2458                                        marked = p->item;
2459                        } else {
2460                                if (!unmarked) {
2461                                        unmarked = p->item;
2462                                        break;
2463                                }
2464                        }
2465                }
2466        }
2467
2468        /*
2469         * If we are TREESAME to a marked-for-deletion parent, but not to any
2470         * unmarked parents, unmark the first TREESAME parent. This is the
2471         * parent that the default simplify_history==1 scan would have followed,
2472         * and it doesn't make sense to omit that path when asking for a
2473         * simplified full history. Retaining it improves the chances of
2474         * understanding odd missed merges that took an old version of a file.
2475         *
2476         * Example:
2477         *
2478         *   I--------*X       A modified the file, but mainline merge X used
2479         *    \       /        "-s ours", so took the version from I. X is
2480         *     `-*A--'         TREESAME to I and !TREESAME to A.
2481         *
2482         * Default log from X would produce "I". Without this check,
2483         * --full-history --simplify-merges would produce "I-A-X", showing
2484         * the merge commit X and that it changed A, but not making clear that
2485         * it had just taken the I version. With this check, the topology above
2486         * is retained.
2487         *
2488         * Note that it is possible that the simplification chooses a different
2489         * TREESAME parent from the default, in which case this test doesn't
2490         * activate, and we _do_ drop the default parent. Example:
2491         *
2492         *   I------X         A modified the file, but it was reverted in B,
2493         *    \    /          meaning mainline merge X is TREESAME to both
2494         *    *A-*B           parents.
2495         *
2496         * Default log would produce "I" by following the first parent;
2497         * --full-history --simplify-merges will produce "I-A-B". But this is a
2498         * reasonable result - it presents a logical full history leading from
2499         * I to X, and X is not an important merge.
2500         */
2501        if (!unmarked && marked) {
2502                marked->object.flags &= ~TMP_MARK;
2503                return 1;
2504        }
2505
2506        return 0;
2507}
2508
2509static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2510{
2511        struct commit_list **pp, *p;
2512        int nth_parent, removed = 0;
2513
2514        pp = &commit->parents;
2515        nth_parent = 0;
2516        while ((p = *pp) != NULL) {
2517                struct commit *parent = p->item;
2518                if (parent->object.flags & TMP_MARK) {
2519                        parent->object.flags &= ~TMP_MARK;
2520                        *pp = p->next;
2521                        free(p);
2522                        removed++;
2523                        compact_treesame(revs, commit, nth_parent);
2524                        continue;
2525                }
2526                pp = &p->next;
2527                nth_parent++;
2528        }
2529
2530        /* Removing parents can only increase TREESAMEness */
2531        if (removed && !(commit->object.flags & TREESAME))
2532                update_treesame(revs, commit);
2533
2534        return nth_parent;
2535}
2536
2537static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2538{
2539        struct commit_list *p;
2540        struct commit *parent;
2541        struct merge_simplify_state *st, *pst;
2542        int cnt;
2543
2544        st = locate_simplify_state(revs, commit);
2545
2546        /*
2547         * Have we handled this one?
2548         */
2549        if (st->simplified)
2550                return tail;
2551
2552        /*
2553         * An UNINTERESTING commit simplifies to itself, so does a
2554         * root commit.  We do not rewrite parents of such commit
2555         * anyway.
2556         */
2557        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2558                st->simplified = commit;
2559                return tail;
2560        }
2561
2562        /*
2563         * Do we know what commit all of our parents that matter
2564         * should be rewritten to?  Otherwise we are not ready to
2565         * rewrite this one yet.
2566         */
2567        for (cnt = 0, p = commit->parents; p; p = p->next) {
2568                pst = locate_simplify_state(revs, p->item);
2569                if (!pst->simplified) {
2570                        tail = &commit_list_insert(p->item, tail)->next;
2571                        cnt++;
2572                }
2573                if (revs->first_parent_only)
2574                        break;
2575        }
2576        if (cnt) {
2577                tail = &commit_list_insert(commit, tail)->next;
2578                return tail;
2579        }
2580
2581        /*
2582         * Rewrite our list of parents. Note that this cannot
2583         * affect our TREESAME flags in any way - a commit is
2584         * always TREESAME to its simplification.
2585         */
2586        for (p = commit->parents; p; p = p->next) {
2587                pst = locate_simplify_state(revs, p->item);
2588                p->item = pst->simplified;
2589                if (revs->first_parent_only)
2590                        break;
2591        }
2592
2593        if (revs->first_parent_only)
2594                cnt = 1;
2595        else
2596                cnt = remove_duplicate_parents(revs, commit);
2597
2598        /*
2599         * It is possible that we are a merge and one side branch
2600         * does not have any commit that touches the given paths;
2601         * in such a case, the immediate parent from that branch
2602         * will be rewritten to be the merge base.
2603         *
2604         *      o----X          X: the commit we are looking at;
2605         *     /    /           o: a commit that touches the paths;
2606         * ---o----'
2607         *
2608         * Further, a merge of an independent branch that doesn't
2609         * touch the path will reduce to a treesame root parent:
2610         *
2611         *  ----o----X          X: the commit we are looking at;
2612         *          /           o: a commit that touches the paths;
2613         *         r            r: a root commit not touching the paths
2614         *
2615         * Detect and simplify both cases.
2616         */
2617        if (1 < cnt) {
2618                int marked = mark_redundant_parents(revs, commit);
2619                marked += mark_treesame_root_parents(revs, commit);
2620                if (marked)
2621                        marked -= leave_one_treesame_to_parent(revs, commit);
2622                if (marked)
2623                        cnt = remove_marked_parents(revs, commit);
2624        }
2625
2626        /*
2627         * A commit simplifies to itself if it is a root, if it is
2628         * UNINTERESTING, if it touches the given paths, or if it is a
2629         * merge and its parents don't simplify to one relevant commit
2630         * (the first two cases are already handled at the beginning of
2631         * this function).
2632         *
2633         * Otherwise, it simplifies to what its sole relevant parent
2634         * simplifies to.
2635         */
2636        if (!cnt ||
2637            (commit->object.flags & UNINTERESTING) ||
2638            !(commit->object.flags & TREESAME) ||
2639            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2640                st->simplified = commit;
2641        else {
2642                pst = locate_simplify_state(revs, parent);
2643                st->simplified = pst->simplified;
2644        }
2645        return tail;
2646}
2647
2648static void simplify_merges(struct rev_info *revs)
2649{
2650        struct commit_list *list, *next;
2651        struct commit_list *yet_to_do, **tail;
2652        struct commit *commit;
2653
2654        if (!revs->prune)
2655                return;
2656
2657        /* feed the list reversed */
2658        yet_to_do = NULL;
2659        for (list = revs->commits; list; list = next) {
2660                commit = list->item;
2661                next = list->next;
2662                /*
2663                 * Do not free(list) here yet; the original list
2664                 * is used later in this function.
2665                 */
2666                commit_list_insert(commit, &yet_to_do);
2667        }
2668        while (yet_to_do) {
2669                list = yet_to_do;
2670                yet_to_do = NULL;
2671                tail = &yet_to_do;
2672                while (list) {
2673                        commit = pop_commit(&list);
2674                        tail = simplify_one(revs, commit, tail);
2675                }
2676        }
2677
2678        /* clean up the result, removing the simplified ones */
2679        list = revs->commits;
2680        revs->commits = NULL;
2681        tail = &revs->commits;
2682        while (list) {
2683                struct merge_simplify_state *st;
2684
2685                commit = pop_commit(&list);
2686                st = locate_simplify_state(revs, commit);
2687                if (st->simplified == commit)
2688                        tail = &commit_list_insert(commit, tail)->next;
2689        }
2690}
2691
2692static void set_children(struct rev_info *revs)
2693{
2694        struct commit_list *l;
2695        for (l = revs->commits; l; l = l->next) {
2696                struct commit *commit = l->item;
2697                struct commit_list *p;
2698
2699                for (p = commit->parents; p; p = p->next)
2700                        add_child(revs, p->item, commit);
2701        }
2702}
2703
2704void reset_revision_walk(void)
2705{
2706        clear_object_flags(SEEN | ADDED | SHOWN);
2707}
2708
2709int prepare_revision_walk(struct rev_info *revs)
2710{
2711        int i;
2712        struct object_array old_pending;
2713        struct commit_list **next = &revs->commits;
2714
2715        memcpy(&old_pending, &revs->pending, sizeof(old_pending));
2716        revs->pending.nr = 0;
2717        revs->pending.alloc = 0;
2718        revs->pending.objects = NULL;
2719        for (i = 0; i < old_pending.nr; i++) {
2720                struct object_array_entry *e = old_pending.objects + i;
2721                struct commit *commit = handle_commit(revs, e);
2722                if (commit) {
2723                        if (!(commit->object.flags & SEEN)) {
2724                                commit->object.flags |= SEEN;
2725                                next = commit_list_append(commit, next);
2726                        }
2727                }
2728        }
2729        if (!revs->leak_pending)
2730                object_array_clear(&old_pending);
2731
2732        /* Signal whether we need per-parent treesame decoration */
2733        if (revs->simplify_merges ||
2734            (revs->limited && limiting_can_increase_treesame(revs)))
2735                revs->treesame.name = "treesame";
2736
2737        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2738                commit_list_sort_by_date(&revs->commits);
2739        if (revs->no_walk)
2740                return 0;
2741        if (revs->limited)
2742                if (limit_list(revs) < 0)
2743                        return -1;
2744        if (revs->topo_order)
2745                sort_in_topological_order(&revs->commits, revs->sort_order);
2746        if (revs->line_level_traverse)
2747                line_log_filter(revs);
2748        if (revs->simplify_merges)
2749                simplify_merges(revs);
2750        if (revs->children.name)
2751                set_children(revs);
2752        return 0;
2753}
2754
2755static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2756{
2757        struct commit_list *cache = NULL;
2758
2759        for (;;) {
2760                struct commit *p = *pp;
2761                if (!revs->limited)
2762                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2763                                return rewrite_one_error;
2764                if (p->object.flags & UNINTERESTING)
2765                        return rewrite_one_ok;
2766                if (!(p->object.flags & TREESAME))
2767                        return rewrite_one_ok;
2768                if (!p->parents)
2769                        return rewrite_one_noparents;
2770                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2771                        return rewrite_one_ok;
2772                *pp = p;
2773        }
2774}
2775
2776int rewrite_parents(struct rev_info *revs, struct commit *commit,
2777        rewrite_parent_fn_t rewrite_parent)
2778{
2779        struct commit_list **pp = &commit->parents;
2780        while (*pp) {
2781                struct commit_list *parent = *pp;
2782                switch (rewrite_parent(revs, &parent->item)) {
2783                case rewrite_one_ok:
2784                        break;
2785                case rewrite_one_noparents:
2786                        *pp = parent->next;
2787                        continue;
2788                case rewrite_one_error:
2789                        return -1;
2790                }
2791                pp = &parent->next;
2792        }
2793        remove_duplicate_parents(revs, commit);
2794        return 0;
2795}
2796
2797static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2798{
2799        char *person, *endp;
2800        size_t len, namelen, maillen;
2801        const char *name;
2802        const char *mail;
2803        struct ident_split ident;
2804
2805        person = strstr(buf->buf, what);
2806        if (!person)
2807                return 0;
2808
2809        person += strlen(what);
2810        endp = strchr(person, '\n');
2811        if (!endp)
2812                return 0;
2813
2814        len = endp - person;
2815
2816        if (split_ident_line(&ident, person, len))
2817                return 0;
2818
2819        mail = ident.mail_begin;
2820        maillen = ident.mail_end - ident.mail_begin;
2821        name = ident.name_begin;
2822        namelen = ident.name_end - ident.name_begin;
2823
2824        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2825                struct strbuf namemail = STRBUF_INIT;
2826
2827                strbuf_addf(&namemail, "%.*s <%.*s>",
2828                            (int)namelen, name, (int)maillen, mail);
2829
2830                strbuf_splice(buf, ident.name_begin - buf->buf,
2831                              ident.mail_end - ident.name_begin + 1,
2832                              namemail.buf, namemail.len);
2833
2834                strbuf_release(&namemail);
2835
2836                return 1;
2837        }
2838
2839        return 0;
2840}
2841
2842static int commit_match(struct commit *commit, struct rev_info *opt)
2843{
2844        int retval;
2845        const char *encoding;
2846        const char *message;
2847        struct strbuf buf = STRBUF_INIT;
2848
2849        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2850                return 1;
2851
2852        /* Prepend "fake" headers as needed */
2853        if (opt->grep_filter.use_reflog_filter) {
2854                strbuf_addstr(&buf, "reflog ");
2855                get_reflog_message(&buf, opt->reflog_info);
2856                strbuf_addch(&buf, '\n');
2857        }
2858
2859        /*
2860         * We grep in the user's output encoding, under the assumption that it
2861         * is the encoding they are most likely to write their grep pattern
2862         * for. In addition, it means we will match the "notes" encoding below,
2863         * so we will not end up with a buffer that has two different encodings
2864         * in it.
2865         */
2866        encoding = get_log_output_encoding();
2867        message = logmsg_reencode(commit, NULL, encoding);
2868
2869        /* Copy the commit to temporary if we are using "fake" headers */
2870        if (buf.len)
2871                strbuf_addstr(&buf, message);
2872
2873        if (opt->grep_filter.header_list && opt->mailmap) {
2874                if (!buf.len)
2875                        strbuf_addstr(&buf, message);
2876
2877                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
2878                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
2879        }
2880
2881        /* Append "fake" message parts as needed */
2882        if (opt->show_notes) {
2883                if (!buf.len)
2884                        strbuf_addstr(&buf, message);
2885                format_display_notes(commit->object.oid.hash, &buf, encoding, 1);
2886        }
2887
2888        /*
2889         * Find either in the original commit message, or in the temporary.
2890         * Note that we cast away the constness of "message" here. It is
2891         * const because it may come from the cached commit buffer. That's OK,
2892         * because we know that it is modifiable heap memory, and that while
2893         * grep_buffer may modify it for speed, it will restore any
2894         * changes before returning.
2895         */
2896        if (buf.len)
2897                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
2898        else
2899                retval = grep_buffer(&opt->grep_filter,
2900                                     (char *)message, strlen(message));
2901        strbuf_release(&buf);
2902        unuse_commit_buffer(commit, message);
2903        return opt->invert_grep ? !retval : retval;
2904}
2905
2906static inline int want_ancestry(const struct rev_info *revs)
2907{
2908        return (revs->rewrite_parents || revs->children.name);
2909}
2910
2911enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
2912{
2913        if (commit->object.flags & SHOWN)
2914                return commit_ignore;
2915        if (revs->unpacked && has_sha1_pack(commit->object.oid.hash))
2916                return commit_ignore;
2917        if (revs->show_all)
2918                return commit_show;
2919        if (commit->object.flags & UNINTERESTING)
2920                return commit_ignore;
2921        if (revs->min_age != -1 && (commit->date > revs->min_age))
2922                return commit_ignore;
2923        if (revs->min_parents || (revs->max_parents >= 0)) {
2924                int n = commit_list_count(commit->parents);
2925                if ((n < revs->min_parents) ||
2926                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
2927                        return commit_ignore;
2928        }
2929        if (!commit_match(commit, revs))
2930                return commit_ignore;
2931        if (revs->prune && revs->dense) {
2932                /* Commit without changes? */
2933                if (commit->object.flags & TREESAME) {
2934                        int n;
2935                        struct commit_list *p;
2936                        /* drop merges unless we want parenthood */
2937                        if (!want_ancestry(revs))
2938                                return commit_ignore;
2939                        /*
2940                         * If we want ancestry, then need to keep any merges
2941                         * between relevant commits to tie together topology.
2942                         * For consistency with TREESAME and simplification
2943                         * use "relevant" here rather than just INTERESTING,
2944                         * to treat bottom commit(s) as part of the topology.
2945                         */
2946                        for (n = 0, p = commit->parents; p; p = p->next)
2947                                if (relevant_commit(p->item))
2948                                        if (++n >= 2)
2949                                                return commit_show;
2950                        return commit_ignore;
2951                }
2952        }
2953        return commit_show;
2954}
2955
2956define_commit_slab(saved_parents, struct commit_list *);
2957
2958#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
2959
2960/*
2961 * You may only call save_parents() once per commit (this is checked
2962 * for non-root commits).
2963 */
2964static void save_parents(struct rev_info *revs, struct commit *commit)
2965{
2966        struct commit_list **pp;
2967
2968        if (!revs->saved_parents_slab) {
2969                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
2970                init_saved_parents(revs->saved_parents_slab);
2971        }
2972
2973        pp = saved_parents_at(revs->saved_parents_slab, commit);
2974
2975        /*
2976         * When walking with reflogs, we may visit the same commit
2977         * several times: once for each appearance in the reflog.
2978         *
2979         * In this case, save_parents() will be called multiple times.
2980         * We want to keep only the first set of parents.  We need to
2981         * store a sentinel value for an empty (i.e., NULL) parent
2982         * list to distinguish it from a not-yet-saved list, however.
2983         */
2984        if (*pp)
2985                return;
2986        if (commit->parents)
2987                *pp = copy_commit_list(commit->parents);
2988        else
2989                *pp = EMPTY_PARENT_LIST;
2990}
2991
2992static void free_saved_parents(struct rev_info *revs)
2993{
2994        if (revs->saved_parents_slab)
2995                clear_saved_parents(revs->saved_parents_slab);
2996}
2997
2998struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
2999{
3000        struct commit_list *parents;
3001
3002        if (!revs->saved_parents_slab)
3003                return commit->parents;
3004
3005        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3006        if (parents == EMPTY_PARENT_LIST)
3007                return NULL;
3008        return parents;
3009}
3010
3011enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
3012{
3013        enum commit_action action = get_commit_action(revs, commit);
3014
3015        if (action == commit_show &&
3016            !revs->show_all &&
3017            revs->prune && revs->dense && want_ancestry(revs)) {
3018                /*
3019                 * --full-diff on simplified parents is no good: it
3020                 * will show spurious changes from the commits that
3021                 * were elided.  So we save the parents on the side
3022                 * when --full-diff is in effect.
3023                 */
3024                if (revs->full_diff)
3025                        save_parents(revs, commit);
3026                if (rewrite_parents(revs, commit, rewrite_one) < 0)
3027                        return commit_error;
3028        }
3029        return action;
3030}
3031
3032static void track_linear(struct rev_info *revs, struct commit *commit)
3033{
3034        if (revs->track_first_time) {
3035                revs->linear = 1;
3036                revs->track_first_time = 0;
3037        } else {
3038                struct commit_list *p;
3039                for (p = revs->previous_parents; p; p = p->next)
3040                        if (p->item == NULL || /* first commit */
3041                            !oidcmp(&p->item->object.oid, &commit->object.oid))
3042                                break;
3043                revs->linear = p != NULL;
3044        }
3045        if (revs->reverse) {
3046                if (revs->linear)
3047                        commit->object.flags |= TRACK_LINEAR;
3048        }
3049        free_commit_list(revs->previous_parents);
3050        revs->previous_parents = copy_commit_list(commit->parents);
3051}
3052
3053static struct commit *get_revision_1(struct rev_info *revs)
3054{
3055        if (!revs->commits)
3056                return NULL;
3057
3058        do {
3059                struct commit *commit = pop_commit(&revs->commits);
3060
3061                if (revs->reflog_info) {
3062                        save_parents(revs, commit);
3063                        fake_reflog_parent(revs->reflog_info, commit);
3064                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
3065                }
3066
3067                /*
3068                 * If we haven't done the list limiting, we need to look at
3069                 * the parents here. We also need to do the date-based limiting
3070                 * that we'd otherwise have done in limit_list().
3071                 */
3072                if (!revs->limited) {
3073                        if (revs->max_age != -1 &&
3074                            (commit->date < revs->max_age))
3075                                continue;
3076                        if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
3077                                if (!revs->ignore_missing_links)
3078                                        die("Failed to traverse parents of commit %s",
3079                                                oid_to_hex(&commit->object.oid));
3080                        }
3081                }
3082
3083                switch (simplify_commit(revs, commit)) {
3084                case commit_ignore:
3085                        continue;
3086                case commit_error:
3087                        die("Failed to simplify parents of commit %s",
3088                            oid_to_hex(&commit->object.oid));
3089                default:
3090                        if (revs->track_linear)
3091                                track_linear(revs, commit);
3092                        return commit;
3093                }
3094        } while (revs->commits);
3095        return NULL;
3096}
3097
3098/*
3099 * Return true for entries that have not yet been shown.  (This is an
3100 * object_array_each_func_t.)
3101 */
3102static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
3103{
3104        return !(entry->item->flags & SHOWN);
3105}
3106
3107/*
3108 * If array is on the verge of a realloc, garbage-collect any entries
3109 * that have already been shown to try to free up some space.
3110 */
3111static void gc_boundary(struct object_array *array)
3112{
3113        if (array->nr == array->alloc)
3114                object_array_filter(array, entry_unshown, NULL);
3115}
3116
3117static void create_boundary_commit_list(struct rev_info *revs)
3118{
3119        unsigned i;
3120        struct commit *c;
3121        struct object_array *array = &revs->boundary_commits;
3122        struct object_array_entry *objects = array->objects;
3123
3124        /*
3125         * If revs->commits is non-NULL at this point, an error occurred in
3126         * get_revision_1().  Ignore the error and continue printing the
3127         * boundary commits anyway.  (This is what the code has always
3128         * done.)
3129         */
3130        if (revs->commits) {
3131                free_commit_list(revs->commits);
3132                revs->commits = NULL;
3133        }
3134
3135        /*
3136         * Put all of the actual boundary commits from revs->boundary_commits
3137         * into revs->commits
3138         */
3139        for (i = 0; i < array->nr; i++) {
3140                c = (struct commit *)(objects[i].item);
3141                if (!c)
3142                        continue;
3143                if (!(c->object.flags & CHILD_SHOWN))
3144                        continue;
3145                if (c->object.flags & (SHOWN | BOUNDARY))
3146                        continue;
3147                c->object.flags |= BOUNDARY;
3148                commit_list_insert(c, &revs->commits);
3149        }
3150
3151        /*
3152         * If revs->topo_order is set, sort the boundary commits
3153         * in topological order
3154         */
3155        sort_in_topological_order(&revs->commits, revs->sort_order);
3156}
3157
3158static struct commit *get_revision_internal(struct rev_info *revs)
3159{
3160        struct commit *c = NULL;
3161        struct commit_list *l;
3162
3163        if (revs->boundary == 2) {
3164                /*
3165                 * All of the normal commits have already been returned,
3166                 * and we are now returning boundary commits.
3167                 * create_boundary_commit_list() has populated
3168                 * revs->commits with the remaining commits to return.
3169                 */
3170                c = pop_commit(&revs->commits);
3171                if (c)
3172                        c->object.flags |= SHOWN;
3173                return c;
3174        }
3175
3176        /*
3177         * If our max_count counter has reached zero, then we are done. We
3178         * don't simply return NULL because we still might need to show
3179         * boundary commits. But we want to avoid calling get_revision_1, which
3180         * might do a considerable amount of work finding the next commit only
3181         * for us to throw it away.
3182         *
3183         * If it is non-zero, then either we don't have a max_count at all
3184         * (-1), or it is still counting, in which case we decrement.
3185         */
3186        if (revs->max_count) {
3187                c = get_revision_1(revs);
3188                if (c) {
3189                        while (revs->skip_count > 0) {
3190                                revs->skip_count--;
3191                                c = get_revision_1(revs);
3192                                if (!c)
3193                                        break;
3194                        }
3195                }
3196
3197                if (revs->max_count > 0)
3198                        revs->max_count--;
3199        }
3200
3201        if (c)
3202                c->object.flags |= SHOWN;
3203
3204        if (!revs->boundary)
3205                return c;
3206
3207        if (!c) {
3208                /*
3209                 * get_revision_1() runs out the commits, and
3210                 * we are done computing the boundaries.
3211                 * switch to boundary commits output mode.
3212                 */
3213                revs->boundary = 2;
3214
3215                /*
3216                 * Update revs->commits to contain the list of
3217                 * boundary commits.
3218                 */
3219                create_boundary_commit_list(revs);
3220
3221                return get_revision_internal(revs);
3222        }
3223
3224        /*
3225         * boundary commits are the commits that are parents of the
3226         * ones we got from get_revision_1() but they themselves are
3227         * not returned from get_revision_1().  Before returning
3228         * 'c', we need to mark its parents that they could be boundaries.
3229         */
3230
3231        for (l = c->parents; l; l = l->next) {
3232                struct object *p;
3233                p = &(l->item->object);
3234                if (p->flags & (CHILD_SHOWN | SHOWN))
3235                        continue;
3236                p->flags |= CHILD_SHOWN;
3237                gc_boundary(&revs->boundary_commits);
3238                add_object_array(p, NULL, &revs->boundary_commits);
3239        }
3240
3241        return c;
3242}
3243
3244struct commit *get_revision(struct rev_info *revs)
3245{
3246        struct commit *c;
3247        struct commit_list *reversed;
3248
3249        if (revs->reverse) {
3250                reversed = NULL;
3251                while ((c = get_revision_internal(revs)))
3252                        commit_list_insert(c, &reversed);
3253                revs->commits = reversed;
3254                revs->reverse = 0;
3255                revs->reverse_output_stage = 1;
3256        }
3257
3258        if (revs->reverse_output_stage) {
3259                c = pop_commit(&revs->commits);
3260                if (revs->track_linear)
3261                        revs->linear = !!(c && c->object.flags & TRACK_LINEAR);
3262                return c;
3263        }
3264
3265        c = get_revision_internal(revs);
3266        if (c && revs->graph)
3267                graph_update(revs->graph, c);
3268        if (!c) {
3269                free_saved_parents(revs);
3270                if (revs->previous_parents) {
3271                        free_commit_list(revs->previous_parents);
3272                        revs->previous_parents = NULL;
3273                }
3274        }
3275        return c;
3276}
3277
3278char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3279{
3280        if (commit->object.flags & BOUNDARY)
3281                return "-";
3282        else if (commit->object.flags & UNINTERESTING)
3283                return "^";
3284        else if (commit->object.flags & PATCHSAME)
3285                return "=";
3286        else if (!revs || revs->left_right) {
3287                if (commit->object.flags & SYMMETRIC_LEFT)
3288                        return "<";
3289                else
3290                        return ">";
3291        } else if (revs->graph)
3292                return "*";
3293        else if (revs->cherry_mark)
3294                return "+";
3295        return "";
3296}
3297
3298void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3299{
3300        char *mark = get_revision_mark(revs, commit);
3301        if (!strlen(mark))
3302                return;
3303        fputs(mark, stdout);
3304        putchar(' ');
3305}