revision.con commit Merge branch 'tg/index-v4-format' (13b49f1)
   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
  21volatile show_early_output_fn_t show_early_output;
  22
  23char *path_name(const struct name_path *path, const char *name)
  24{
  25        const struct name_path *p;
  26        char *n, *m;
  27        int nlen = strlen(name);
  28        int len = nlen + 1;
  29
  30        for (p = path; p; p = p->up) {
  31                if (p->elem_len)
  32                        len += p->elem_len + 1;
  33        }
  34        n = xmalloc(len);
  35        m = n + len - (nlen + 1);
  36        strcpy(m, name);
  37        for (p = path; p; p = p->up) {
  38                if (p->elem_len) {
  39                        m -= p->elem_len + 1;
  40                        memcpy(m, p->elem, p->elem_len);
  41                        m[p->elem_len] = '/';
  42                }
  43        }
  44        return n;
  45}
  46
  47static int show_path_component_truncated(FILE *out, const char *name, int len)
  48{
  49        int cnt;
  50        for (cnt = 0; cnt < len; cnt++) {
  51                int ch = name[cnt];
  52                if (!ch || ch == '\n')
  53                        return -1;
  54                fputc(ch, out);
  55        }
  56        return len;
  57}
  58
  59static int show_path_truncated(FILE *out, const struct name_path *path)
  60{
  61        int emitted, ours;
  62
  63        if (!path)
  64                return 0;
  65        emitted = show_path_truncated(out, path->up);
  66        if (emitted < 0)
  67                return emitted;
  68        if (emitted)
  69                fputc('/', out);
  70        ours = show_path_component_truncated(out, path->elem, path->elem_len);
  71        if (ours < 0)
  72                return ours;
  73        return ours || emitted;
  74}
  75
  76void show_object_with_name(FILE *out, struct object *obj,
  77                           const struct name_path *path, const char *component)
  78{
  79        struct name_path leaf;
  80        leaf.up = (struct name_path *)path;
  81        leaf.elem = component;
  82        leaf.elem_len = strlen(component);
  83
  84        fprintf(out, "%s ", sha1_to_hex(obj->sha1));
  85        show_path_truncated(out, &leaf);
  86        fputc('\n', out);
  87}
  88
  89void add_object(struct object *obj,
  90                struct object_array *p,
  91                struct name_path *path,
  92                const char *name)
  93{
  94        char *pn = path_name(path, name);
  95        add_object_array(obj, pn, p);
  96        free(pn);
  97}
  98
  99static void mark_blob_uninteresting(struct blob *blob)
 100{
 101        if (!blob)
 102                return;
 103        if (blob->object.flags & UNINTERESTING)
 104                return;
 105        blob->object.flags |= UNINTERESTING;
 106}
 107
 108static void mark_tree_contents_uninteresting(struct tree *tree)
 109{
 110        struct tree_desc desc;
 111        struct name_entry entry;
 112        struct object *obj = &tree->object;
 113
 114        if (!has_sha1_file(obj->sha1))
 115                return;
 116        if (parse_tree(tree) < 0)
 117                die("bad tree %s", sha1_to_hex(obj->sha1));
 118
 119        init_tree_desc(&desc, tree->buffer, tree->size);
 120        while (tree_entry(&desc, &entry)) {
 121                switch (object_type(entry.mode)) {
 122                case OBJ_TREE:
 123                        mark_tree_uninteresting(lookup_tree(entry.sha1));
 124                        break;
 125                case OBJ_BLOB:
 126                        mark_blob_uninteresting(lookup_blob(entry.sha1));
 127                        break;
 128                default:
 129                        /* Subproject commit - not in this repository */
 130                        break;
 131                }
 132        }
 133
 134        /*
 135         * We don't care about the tree any more
 136         * after it has been marked uninteresting.
 137         */
 138        free_tree_buffer(tree);
 139}
 140
 141void mark_tree_uninteresting(struct tree *tree)
 142{
 143        struct object *obj = &tree->object;
 144
 145        if (!tree)
 146                return;
 147        if (obj->flags & UNINTERESTING)
 148                return;
 149        obj->flags |= UNINTERESTING;
 150        mark_tree_contents_uninteresting(tree);
 151}
 152
 153void mark_parents_uninteresting(struct commit *commit)
 154{
 155        struct commit_list *parents = NULL, *l;
 156
 157        for (l = commit->parents; l; l = l->next)
 158                commit_list_insert(l->item, &parents);
 159
 160        while (parents) {
 161                struct commit *commit = parents->item;
 162                l = parents;
 163                parents = parents->next;
 164                free(l);
 165
 166                while (commit) {
 167                        /*
 168                         * A missing commit is ok iff its parent is marked
 169                         * uninteresting.
 170                         *
 171                         * We just mark such a thing parsed, so that when
 172                         * it is popped next time around, we won't be trying
 173                         * to parse it and get an error.
 174                         */
 175                        if (!has_sha1_file(commit->object.sha1))
 176                                commit->object.parsed = 1;
 177
 178                        if (commit->object.flags & UNINTERESTING)
 179                                break;
 180
 181                        commit->object.flags |= UNINTERESTING;
 182
 183                        /*
 184                         * Normally we haven't parsed the parent
 185                         * yet, so we won't have a parent of a parent
 186                         * here. However, it may turn out that we've
 187                         * reached this commit some other way (where it
 188                         * wasn't uninteresting), in which case we need
 189                         * to mark its parents recursively too..
 190                         */
 191                        if (!commit->parents)
 192                                break;
 193
 194                        for (l = commit->parents->next; l; l = l->next)
 195                                commit_list_insert(l->item, &parents);
 196                        commit = commit->parents->item;
 197                }
 198        }
 199}
 200
 201static void add_pending_object_with_mode(struct rev_info *revs,
 202                                         struct object *obj,
 203                                         const char *name, unsigned mode)
 204{
 205        if (!obj)
 206                return;
 207        if (revs->no_walk && (obj->flags & UNINTERESTING))
 208                revs->no_walk = 0;
 209        if (revs->reflog_info && obj->type == OBJ_COMMIT) {
 210                struct strbuf buf = STRBUF_INIT;
 211                int len = interpret_branch_name(name, 0, &buf);
 212                int st;
 213
 214                if (0 < len && name[len] && buf.len)
 215                        strbuf_addstr(&buf, name + len);
 216                st = add_reflog_for_walk(revs->reflog_info,
 217                                         (struct commit *)obj,
 218                                         buf.buf[0] ? buf.buf: name);
 219                strbuf_release(&buf);
 220                if (st)
 221                        return;
 222        }
 223        add_object_array_with_mode(obj, name, &revs->pending, mode);
 224}
 225
 226void add_pending_object(struct rev_info *revs,
 227                        struct object *obj, const char *name)
 228{
 229        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 230}
 231
 232void add_head_to_pending(struct rev_info *revs)
 233{
 234        unsigned char sha1[20];
 235        struct object *obj;
 236        if (get_sha1("HEAD", sha1))
 237                return;
 238        obj = parse_object(sha1);
 239        if (!obj)
 240                return;
 241        add_pending_object(revs, obj, "HEAD");
 242}
 243
 244static struct object *get_reference(struct rev_info *revs, const char *name,
 245                                    const unsigned char *sha1,
 246                                    unsigned int flags)
 247{
 248        struct object *object;
 249
 250        object = parse_object(sha1);
 251        if (!object) {
 252                if (revs->ignore_missing)
 253                        return object;
 254                die("bad object %s", name);
 255        }
 256        object->flags |= flags;
 257        return object;
 258}
 259
 260void add_pending_sha1(struct rev_info *revs, const char *name,
 261                      const unsigned char *sha1, unsigned int flags)
 262{
 263        struct object *object = get_reference(revs, name, sha1, flags);
 264        add_pending_object(revs, object, name);
 265}
 266
 267static struct commit *handle_commit(struct rev_info *revs,
 268                                    struct object *object, const char *name)
 269{
 270        unsigned long flags = object->flags;
 271
 272        /*
 273         * Tag object? Look what it points to..
 274         */
 275        while (object->type == OBJ_TAG) {
 276                struct tag *tag = (struct tag *) object;
 277                if (revs->tag_objects && !(flags & UNINTERESTING))
 278                        add_pending_object(revs, object, tag->tag);
 279                if (!tag->tagged)
 280                        die("bad tag");
 281                object = parse_object(tag->tagged->sha1);
 282                if (!object) {
 283                        if (flags & UNINTERESTING)
 284                                return NULL;
 285                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 286                }
 287                object->flags |= flags;
 288        }
 289
 290        /*
 291         * Commit object? Just return it, we'll do all the complex
 292         * reachability crud.
 293         */
 294        if (object->type == OBJ_COMMIT) {
 295                struct commit *commit = (struct commit *)object;
 296                if (parse_commit(commit) < 0)
 297                        die("unable to parse commit %s", name);
 298                if (flags & UNINTERESTING) {
 299                        mark_parents_uninteresting(commit);
 300                        revs->limited = 1;
 301                }
 302                if (revs->show_source && !commit->util)
 303                        commit->util = (void *) name;
 304                return commit;
 305        }
 306
 307        /*
 308         * Tree object? Either mark it uninteresting, or add it
 309         * to the list of objects to look at later..
 310         */
 311        if (object->type == OBJ_TREE) {
 312                struct tree *tree = (struct tree *)object;
 313                if (!revs->tree_objects)
 314                        return NULL;
 315                if (flags & UNINTERESTING) {
 316                        mark_tree_contents_uninteresting(tree);
 317                        return NULL;
 318                }
 319                add_pending_object(revs, object, "");
 320                return NULL;
 321        }
 322
 323        /*
 324         * Blob object? You know the drill by now..
 325         */
 326        if (object->type == OBJ_BLOB) {
 327                if (!revs->blob_objects)
 328                        return NULL;
 329                if (flags & UNINTERESTING)
 330                        return NULL;
 331                add_pending_object(revs, object, "");
 332                return NULL;
 333        }
 334        die("%s is unknown object", name);
 335}
 336
 337static int everybody_uninteresting(struct commit_list *orig)
 338{
 339        struct commit_list *list = orig;
 340        while (list) {
 341                struct commit *commit = list->item;
 342                list = list->next;
 343                if (commit->object.flags & UNINTERESTING)
 344                        continue;
 345                return 0;
 346        }
 347        return 1;
 348}
 349
 350/*
 351 * A definition of "relevant" commit that we can use to simplify limited graphs
 352 * by eliminating side branches.
 353 *
 354 * A "relevant" commit is one that is !UNINTERESTING (ie we are including it
 355 * in our list), or that is a specified BOTTOM commit. Then after computing
 356 * a limited list, during processing we can generally ignore boundary merges
 357 * coming from outside the graph, (ie from irrelevant parents), and treat
 358 * those merges as if they were single-parent. TREESAME is defined to consider
 359 * only relevant parents, if any. If we are TREESAME to our on-graph parents,
 360 * we don't care if we were !TREESAME to non-graph parents.
 361 *
 362 * Treating bottom commits as relevant ensures that a limited graph's
 363 * connection to the actual bottom commit is not viewed as a side branch, but
 364 * treated as part of the graph. For example:
 365 *
 366 *   ....Z...A---X---o---o---B
 367 *        .     /
 368 *         W---Y
 369 *
 370 * When computing "A..B", the A-X connection is at least as important as
 371 * Y-X, despite A being flagged UNINTERESTING.
 372 *
 373 * And when computing --ancestry-path "A..B", the A-X connection is more
 374 * important than Y-X, despite both A and Y being flagged UNINTERESTING.
 375 */
 376static inline int relevant_commit(struct commit *commit)
 377{
 378        return (commit->object.flags & (UNINTERESTING | BOTTOM)) != UNINTERESTING;
 379}
 380
 381/*
 382 * Return a single relevant commit from a parent list. If we are a TREESAME
 383 * commit, and this selects one of our parents, then we can safely simplify to
 384 * that parent.
 385 */
 386static struct commit *one_relevant_parent(const struct rev_info *revs,
 387                                          struct commit_list *orig)
 388{
 389        struct commit_list *list = orig;
 390        struct commit *relevant = NULL;
 391
 392        if (!orig)
 393                return NULL;
 394
 395        /*
 396         * For 1-parent commits, or if first-parent-only, then return that
 397         * first parent (even if not "relevant" by the above definition).
 398         * TREESAME will have been set purely on that parent.
 399         */
 400        if (revs->first_parent_only || !orig->next)
 401                return orig->item;
 402
 403        /*
 404         * For multi-parent commits, identify a sole relevant parent, if any.
 405         * If we have only one relevant parent, then TREESAME will be set purely
 406         * with regard to that parent, and we can simplify accordingly.
 407         *
 408         * If we have more than one relevant parent, or no relevant parents
 409         * (and multiple irrelevant ones), then we can't select a parent here
 410         * and return NULL.
 411         */
 412        while (list) {
 413                struct commit *commit = list->item;
 414                list = list->next;
 415                if (relevant_commit(commit)) {
 416                        if (relevant)
 417                                return NULL;
 418                        relevant = commit;
 419                }
 420        }
 421        return relevant;
 422}
 423
 424/*
 425 * The goal is to get REV_TREE_NEW as the result only if the
 426 * diff consists of all '+' (and no other changes), REV_TREE_OLD
 427 * if the whole diff is removal of old data, and otherwise
 428 * REV_TREE_DIFFERENT (of course if the trees are the same we
 429 * want REV_TREE_SAME).
 430 * That means that once we get to REV_TREE_DIFFERENT, we do not
 431 * have to look any further.
 432 */
 433static int tree_difference = REV_TREE_SAME;
 434
 435static void file_add_remove(struct diff_options *options,
 436                    int addremove, unsigned mode,
 437                    const unsigned char *sha1,
 438                    int sha1_valid,
 439                    const char *fullpath, unsigned dirty_submodule)
 440{
 441        int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 442
 443        tree_difference |= diff;
 444        if (tree_difference == REV_TREE_DIFFERENT)
 445                DIFF_OPT_SET(options, HAS_CHANGES);
 446}
 447
 448static void file_change(struct diff_options *options,
 449                 unsigned old_mode, unsigned new_mode,
 450                 const unsigned char *old_sha1,
 451                 const unsigned char *new_sha1,
 452                 int old_sha1_valid, int new_sha1_valid,
 453                 const char *fullpath,
 454                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 455{
 456        tree_difference = REV_TREE_DIFFERENT;
 457        DIFF_OPT_SET(options, HAS_CHANGES);
 458}
 459
 460static int rev_compare_tree(struct rev_info *revs,
 461                            struct commit *parent, struct commit *commit)
 462{
 463        struct tree *t1 = parent->tree;
 464        struct tree *t2 = commit->tree;
 465
 466        if (!t1)
 467                return REV_TREE_NEW;
 468        if (!t2)
 469                return REV_TREE_OLD;
 470
 471        if (revs->simplify_by_decoration) {
 472                /*
 473                 * If we are simplifying by decoration, then the commit
 474                 * is worth showing if it has a tag pointing at it.
 475                 */
 476                if (lookup_decoration(&name_decoration, &commit->object))
 477                        return REV_TREE_DIFFERENT;
 478                /*
 479                 * A commit that is not pointed by a tag is uninteresting
 480                 * if we are not limited by path.  This means that you will
 481                 * see the usual "commits that touch the paths" plus any
 482                 * tagged commit by specifying both --simplify-by-decoration
 483                 * and pathspec.
 484                 */
 485                if (!revs->prune_data.nr)
 486                        return REV_TREE_SAME;
 487        }
 488
 489        tree_difference = REV_TREE_SAME;
 490        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 491        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 492                           &revs->pruning) < 0)
 493                return REV_TREE_DIFFERENT;
 494        return tree_difference;
 495}
 496
 497static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 498{
 499        int retval;
 500        struct tree *t1 = commit->tree;
 501
 502        if (!t1)
 503                return 0;
 504
 505        tree_difference = REV_TREE_SAME;
 506        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 507        retval = diff_tree_sha1(NULL, t1->object.sha1, "", &revs->pruning);
 508
 509        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 510}
 511
 512struct treesame_state {
 513        unsigned int nparents;
 514        unsigned char treesame[FLEX_ARRAY];
 515};
 516
 517static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 518{
 519        unsigned n = commit_list_count(commit->parents);
 520        struct treesame_state *st = xcalloc(1, sizeof(*st) + n);
 521        st->nparents = n;
 522        add_decoration(&revs->treesame, &commit->object, st);
 523        return st;
 524}
 525
 526/*
 527 * Must be called immediately after removing the nth_parent from a commit's
 528 * parent list, if we are maintaining the per-parent treesame[] decoration.
 529 * This does not recalculate the master TREESAME flag - update_treesame()
 530 * should be called to update it after a sequence of treesame[] modifications
 531 * that may have affected it.
 532 */
 533static int compact_treesame(struct rev_info *revs, struct commit *commit, unsigned nth_parent)
 534{
 535        struct treesame_state *st;
 536        int old_same;
 537
 538        if (!commit->parents) {
 539                /*
 540                 * Have just removed the only parent from a non-merge.
 541                 * Different handling, as we lack decoration.
 542                 */
 543                if (nth_parent != 0)
 544                        die("compact_treesame %u", nth_parent);
 545                old_same = !!(commit->object.flags & TREESAME);
 546                if (rev_same_tree_as_empty(revs, commit))
 547                        commit->object.flags |= TREESAME;
 548                else
 549                        commit->object.flags &= ~TREESAME;
 550                return old_same;
 551        }
 552
 553        st = lookup_decoration(&revs->treesame, &commit->object);
 554        if (!st || nth_parent >= st->nparents)
 555                die("compact_treesame %u", nth_parent);
 556
 557        old_same = st->treesame[nth_parent];
 558        memmove(st->treesame + nth_parent,
 559                st->treesame + nth_parent + 1,
 560                st->nparents - nth_parent - 1);
 561
 562        /*
 563         * If we've just become a non-merge commit, update TREESAME
 564         * immediately, and remove the no-longer-needed decoration.
 565         * If still a merge, defer update until update_treesame().
 566         */
 567        if (--st->nparents == 1) {
 568                if (commit->parents->next)
 569                        die("compact_treesame parents mismatch");
 570                if (st->treesame[0] && revs->dense)
 571                        commit->object.flags |= TREESAME;
 572                else
 573                        commit->object.flags &= ~TREESAME;
 574                free(add_decoration(&revs->treesame, &commit->object, NULL));
 575        }
 576
 577        return old_same;
 578}
 579
 580static unsigned update_treesame(struct rev_info *revs, struct commit *commit)
 581{
 582        if (commit->parents && commit->parents->next) {
 583                unsigned n;
 584                struct treesame_state *st;
 585                struct commit_list *p;
 586                unsigned relevant_parents;
 587                unsigned relevant_change, irrelevant_change;
 588
 589                st = lookup_decoration(&revs->treesame, &commit->object);
 590                if (!st)
 591                        die("update_treesame %s", sha1_to_hex(commit->object.sha1));
 592                relevant_parents = 0;
 593                relevant_change = irrelevant_change = 0;
 594                for (p = commit->parents, n = 0; p; n++, p = p->next) {
 595                        if (relevant_commit(p->item)) {
 596                                relevant_change |= !st->treesame[n];
 597                                relevant_parents++;
 598                        } else
 599                                irrelevant_change |= !st->treesame[n];
 600                }
 601                if (relevant_parents ? relevant_change : irrelevant_change)
 602                        commit->object.flags &= ~TREESAME;
 603                else
 604                        commit->object.flags |= TREESAME;
 605        }
 606
 607        return commit->object.flags & TREESAME;
 608}
 609
 610static inline int limiting_can_increase_treesame(const struct rev_info *revs)
 611{
 612        /*
 613         * TREESAME is irrelevant unless prune && dense;
 614         * if simplify_history is set, we can't have a mixture of TREESAME and
 615         *    !TREESAME INTERESTING parents (and we don't have treesame[]
 616         *    decoration anyway);
 617         * if first_parent_only is set, then the TREESAME flag is locked
 618         *    against the first parent (and again we lack treesame[] decoration).
 619         */
 620        return revs->prune && revs->dense &&
 621               !revs->simplify_history &&
 622               !revs->first_parent_only;
 623}
 624
 625static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 626{
 627        struct commit_list **pp, *parent;
 628        struct treesame_state *ts = NULL;
 629        int relevant_change = 0, irrelevant_change = 0;
 630        int relevant_parents, nth_parent;
 631
 632        /*
 633         * If we don't do pruning, everything is interesting
 634         */
 635        if (!revs->prune)
 636                return;
 637
 638        if (!commit->tree)
 639                return;
 640
 641        if (!commit->parents) {
 642                if (rev_same_tree_as_empty(revs, commit))
 643                        commit->object.flags |= TREESAME;
 644                return;
 645        }
 646
 647        /*
 648         * Normal non-merge commit? If we don't want to make the
 649         * history dense, we consider it always to be a change..
 650         */
 651        if (!revs->dense && !commit->parents->next)
 652                return;
 653
 654        for (pp = &commit->parents, nth_parent = 0, relevant_parents = 0;
 655             (parent = *pp) != NULL;
 656             pp = &parent->next, nth_parent++) {
 657                struct commit *p = parent->item;
 658                if (relevant_commit(p))
 659                        relevant_parents++;
 660
 661                if (nth_parent == 1) {
 662                        /*
 663                         * This our second loop iteration - so we now know
 664                         * we're dealing with a merge.
 665                         *
 666                         * Do not compare with later parents when we care only about
 667                         * the first parent chain, in order to avoid derailing the
 668                         * traversal to follow a side branch that brought everything
 669                         * in the path we are limited to by the pathspec.
 670                         */
 671                        if (revs->first_parent_only)
 672                                break;
 673                        /*
 674                         * If this will remain a potentially-simplifiable
 675                         * merge, remember per-parent treesame if needed.
 676                         * Initialise the array with the comparison from our
 677                         * first iteration.
 678                         */
 679                        if (revs->treesame.name &&
 680                            !revs->simplify_history &&
 681                            !(commit->object.flags & UNINTERESTING)) {
 682                                ts = initialise_treesame(revs, commit);
 683                                if (!(irrelevant_change || relevant_change))
 684                                        ts->treesame[0] = 1;
 685                        }
 686                }
 687                if (parse_commit(p) < 0)
 688                        die("cannot simplify commit %s (because of %s)",
 689                            sha1_to_hex(commit->object.sha1),
 690                            sha1_to_hex(p->object.sha1));
 691                switch (rev_compare_tree(revs, p, commit)) {
 692                case REV_TREE_SAME:
 693                        if (!revs->simplify_history || !relevant_commit(p)) {
 694                                /* Even if a merge with an uninteresting
 695                                 * side branch brought the entire change
 696                                 * we are interested in, we do not want
 697                                 * to lose the other branches of this
 698                                 * merge, so we just keep going.
 699                                 */
 700                                if (ts)
 701                                        ts->treesame[nth_parent] = 1;
 702                                continue;
 703                        }
 704                        parent->next = NULL;
 705                        commit->parents = parent;
 706                        commit->object.flags |= TREESAME;
 707                        return;
 708
 709                case REV_TREE_NEW:
 710                        if (revs->remove_empty_trees &&
 711                            rev_same_tree_as_empty(revs, p)) {
 712                                /* We are adding all the specified
 713                                 * paths from this parent, so the
 714                                 * history beyond this parent is not
 715                                 * interesting.  Remove its parents
 716                                 * (they are grandparents for us).
 717                                 * IOW, we pretend this parent is a
 718                                 * "root" commit.
 719                                 */
 720                                if (parse_commit(p) < 0)
 721                                        die("cannot simplify commit %s (invalid %s)",
 722                                            sha1_to_hex(commit->object.sha1),
 723                                            sha1_to_hex(p->object.sha1));
 724                                p->parents = NULL;
 725                        }
 726                /* fallthrough */
 727                case REV_TREE_OLD:
 728                case REV_TREE_DIFFERENT:
 729                        if (relevant_commit(p))
 730                                relevant_change = 1;
 731                        else
 732                                irrelevant_change = 1;
 733                        continue;
 734                }
 735                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 736        }
 737
 738        /*
 739         * TREESAME is straightforward for single-parent commits. For merge
 740         * commits, it is most useful to define it so that "irrelevant"
 741         * parents cannot make us !TREESAME - if we have any relevant
 742         * parents, then we only consider TREESAMEness with respect to them,
 743         * allowing irrelevant merges from uninteresting branches to be
 744         * simplified away. Only if we have only irrelevant parents do we
 745         * base TREESAME on them. Note that this logic is replicated in
 746         * update_treesame, which should be kept in sync.
 747         */
 748        if (relevant_parents ? !relevant_change : !irrelevant_change)
 749                commit->object.flags |= TREESAME;
 750}
 751
 752static void commit_list_insert_by_date_cached(struct commit *p, struct commit_list **head,
 753                    struct commit_list *cached_base, struct commit_list **cache)
 754{
 755        struct commit_list *new_entry;
 756
 757        if (cached_base && p->date < cached_base->item->date)
 758                new_entry = commit_list_insert_by_date(p, &cached_base->next);
 759        else
 760                new_entry = commit_list_insert_by_date(p, head);
 761
 762        if (cache && (!*cache || p->date < (*cache)->item->date))
 763                *cache = new_entry;
 764}
 765
 766static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 767                    struct commit_list **list, struct commit_list **cache_ptr)
 768{
 769        struct commit_list *parent = commit->parents;
 770        unsigned left_flag;
 771        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 772
 773        if (commit->object.flags & ADDED)
 774                return 0;
 775        commit->object.flags |= ADDED;
 776
 777        if (revs->include_check &&
 778            !revs->include_check(commit, revs->include_check_data))
 779                return 0;
 780
 781        /*
 782         * If the commit is uninteresting, don't try to
 783         * prune parents - we want the maximal uninteresting
 784         * set.
 785         *
 786         * Normally we haven't parsed the parent
 787         * yet, so we won't have a parent of a parent
 788         * here. However, it may turn out that we've
 789         * reached this commit some other way (where it
 790         * wasn't uninteresting), in which case we need
 791         * to mark its parents recursively too..
 792         */
 793        if (commit->object.flags & UNINTERESTING) {
 794                while (parent) {
 795                        struct commit *p = parent->item;
 796                        parent = parent->next;
 797                        if (p)
 798                                p->object.flags |= UNINTERESTING;
 799                        if (parse_commit(p) < 0)
 800                                continue;
 801                        if (p->parents)
 802                                mark_parents_uninteresting(p);
 803                        if (p->object.flags & SEEN)
 804                                continue;
 805                        p->object.flags |= SEEN;
 806                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 807                }
 808                return 0;
 809        }
 810
 811        /*
 812         * Ok, the commit wasn't uninteresting. Try to
 813         * simplify the commit history and find the parent
 814         * that has no differences in the path set if one exists.
 815         */
 816        try_to_simplify_commit(revs, commit);
 817
 818        if (revs->no_walk)
 819                return 0;
 820
 821        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 822
 823        for (parent = commit->parents; parent; parent = parent->next) {
 824                struct commit *p = parent->item;
 825
 826                if (parse_commit(p) < 0)
 827                        return -1;
 828                if (revs->show_source && !p->util)
 829                        p->util = commit->util;
 830                p->object.flags |= left_flag;
 831                if (!(p->object.flags & SEEN)) {
 832                        p->object.flags |= SEEN;
 833                        commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 834                }
 835                if (revs->first_parent_only)
 836                        break;
 837        }
 838        return 0;
 839}
 840
 841static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 842{
 843        struct commit_list *p;
 844        int left_count = 0, right_count = 0;
 845        int left_first;
 846        struct patch_ids ids;
 847        unsigned cherry_flag;
 848
 849        /* First count the commits on the left and on the right */
 850        for (p = list; p; p = p->next) {
 851                struct commit *commit = p->item;
 852                unsigned flags = commit->object.flags;
 853                if (flags & BOUNDARY)
 854                        ;
 855                else if (flags & SYMMETRIC_LEFT)
 856                        left_count++;
 857                else
 858                        right_count++;
 859        }
 860
 861        if (!left_count || !right_count)
 862                return;
 863
 864        left_first = left_count < right_count;
 865        init_patch_ids(&ids);
 866        ids.diffopts.pathspec = revs->diffopt.pathspec;
 867
 868        /* Compute patch-ids for one side */
 869        for (p = list; p; p = p->next) {
 870                struct commit *commit = p->item;
 871                unsigned flags = commit->object.flags;
 872
 873                if (flags & BOUNDARY)
 874                        continue;
 875                /*
 876                 * If we have fewer left, left_first is set and we omit
 877                 * commits on the right branch in this loop.  If we have
 878                 * fewer right, we skip the left ones.
 879                 */
 880                if (left_first != !!(flags & SYMMETRIC_LEFT))
 881                        continue;
 882                commit->util = add_commit_patch_id(commit, &ids);
 883        }
 884
 885        /* either cherry_mark or cherry_pick are true */
 886        cherry_flag = revs->cherry_mark ? PATCHSAME : SHOWN;
 887
 888        /* Check the other side */
 889        for (p = list; p; p = p->next) {
 890                struct commit *commit = p->item;
 891                struct patch_id *id;
 892                unsigned flags = commit->object.flags;
 893
 894                if (flags & BOUNDARY)
 895                        continue;
 896                /*
 897                 * If we have fewer left, left_first is set and we omit
 898                 * commits on the left branch in this loop.
 899                 */
 900                if (left_first == !!(flags & SYMMETRIC_LEFT))
 901                        continue;
 902
 903                /*
 904                 * Have we seen the same patch id?
 905                 */
 906                id = has_commit_patch_id(commit, &ids);
 907                if (!id)
 908                        continue;
 909                id->seen = 1;
 910                commit->object.flags |= cherry_flag;
 911        }
 912
 913        /* Now check the original side for seen ones */
 914        for (p = list; p; p = p->next) {
 915                struct commit *commit = p->item;
 916                struct patch_id *ent;
 917
 918                ent = commit->util;
 919                if (!ent)
 920                        continue;
 921                if (ent->seen)
 922                        commit->object.flags |= cherry_flag;
 923                commit->util = NULL;
 924        }
 925
 926        free_patch_ids(&ids);
 927}
 928
 929/* How many extra uninteresting commits we want to see.. */
 930#define SLOP 5
 931
 932static int still_interesting(struct commit_list *src, unsigned long date, int slop)
 933{
 934        /*
 935         * No source list at all? We're definitely done..
 936         */
 937        if (!src)
 938                return 0;
 939
 940        /*
 941         * Does the destination list contain entries with a date
 942         * before the source list? Definitely _not_ done.
 943         */
 944        if (date <= src->item->date)
 945                return SLOP;
 946
 947        /*
 948         * Does the source list still have interesting commits in
 949         * it? Definitely not done..
 950         */
 951        if (!everybody_uninteresting(src))
 952                return SLOP;
 953
 954        /* Ok, we're closing in.. */
 955        return slop-1;
 956}
 957
 958/*
 959 * "rev-list --ancestry-path A..B" computes commits that are ancestors
 960 * of B but not ancestors of A but further limits the result to those
 961 * that are descendants of A.  This takes the list of bottom commits and
 962 * the result of "A..B" without --ancestry-path, and limits the latter
 963 * further to the ones that can reach one of the commits in "bottom".
 964 */
 965static void limit_to_ancestry(struct commit_list *bottom, struct commit_list *list)
 966{
 967        struct commit_list *p;
 968        struct commit_list *rlist = NULL;
 969        int made_progress;
 970
 971        /*
 972         * Reverse the list so that it will be likely that we would
 973         * process parents before children.
 974         */
 975        for (p = list; p; p = p->next)
 976                commit_list_insert(p->item, &rlist);
 977
 978        for (p = bottom; p; p = p->next)
 979                p->item->object.flags |= TMP_MARK;
 980
 981        /*
 982         * Mark the ones that can reach bottom commits in "list",
 983         * in a bottom-up fashion.
 984         */
 985        do {
 986                made_progress = 0;
 987                for (p = rlist; p; p = p->next) {
 988                        struct commit *c = p->item;
 989                        struct commit_list *parents;
 990                        if (c->object.flags & (TMP_MARK | UNINTERESTING))
 991                                continue;
 992                        for (parents = c->parents;
 993                             parents;
 994                             parents = parents->next) {
 995                                if (!(parents->item->object.flags & TMP_MARK))
 996                                        continue;
 997                                c->object.flags |= TMP_MARK;
 998                                made_progress = 1;
 999                                break;
1000                        }
1001                }
1002        } while (made_progress);
1003
1004        /*
1005         * NEEDSWORK: decide if we want to remove parents that are
1006         * not marked with TMP_MARK from commit->parents for commits
1007         * in the resulting list.  We may not want to do that, though.
1008         */
1009
1010        /*
1011         * The ones that are not marked with TMP_MARK are uninteresting
1012         */
1013        for (p = list; p; p = p->next) {
1014                struct commit *c = p->item;
1015                if (c->object.flags & TMP_MARK)
1016                        continue;
1017                c->object.flags |= UNINTERESTING;
1018        }
1019
1020        /* We are done with the TMP_MARK */
1021        for (p = list; p; p = p->next)
1022                p->item->object.flags &= ~TMP_MARK;
1023        for (p = bottom; p; p = p->next)
1024                p->item->object.flags &= ~TMP_MARK;
1025        free_commit_list(rlist);
1026}
1027
1028/*
1029 * Before walking the history, keep the set of "negative" refs the
1030 * caller has asked to exclude.
1031 *
1032 * This is used to compute "rev-list --ancestry-path A..B", as we need
1033 * to filter the result of "A..B" further to the ones that can actually
1034 * reach A.
1035 */
1036static struct commit_list *collect_bottom_commits(struct commit_list *list)
1037{
1038        struct commit_list *elem, *bottom = NULL;
1039        for (elem = list; elem; elem = elem->next)
1040                if (elem->item->object.flags & BOTTOM)
1041                        commit_list_insert(elem->item, &bottom);
1042        return bottom;
1043}
1044
1045/* Assumes either left_only or right_only is set */
1046static void limit_left_right(struct commit_list *list, struct rev_info *revs)
1047{
1048        struct commit_list *p;
1049
1050        for (p = list; p; p = p->next) {
1051                struct commit *commit = p->item;
1052
1053                if (revs->right_only) {
1054                        if (commit->object.flags & SYMMETRIC_LEFT)
1055                                commit->object.flags |= SHOWN;
1056                } else  /* revs->left_only is set */
1057                        if (!(commit->object.flags & SYMMETRIC_LEFT))
1058                                commit->object.flags |= SHOWN;
1059        }
1060}
1061
1062static int limit_list(struct rev_info *revs)
1063{
1064        int slop = SLOP;
1065        unsigned long date = ~0ul;
1066        struct commit_list *list = revs->commits;
1067        struct commit_list *newlist = NULL;
1068        struct commit_list **p = &newlist;
1069        struct commit_list *bottom = NULL;
1070
1071        if (revs->ancestry_path) {
1072                bottom = collect_bottom_commits(list);
1073                if (!bottom)
1074                        die("--ancestry-path given but there are no bottom commits");
1075        }
1076
1077        while (list) {
1078                struct commit_list *entry = list;
1079                struct commit *commit = list->item;
1080                struct object *obj = &commit->object;
1081                show_early_output_fn_t show;
1082
1083                list = list->next;
1084                free(entry);
1085
1086                if (revs->max_age != -1 && (commit->date < revs->max_age))
1087                        obj->flags |= UNINTERESTING;
1088                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
1089                        return -1;
1090                if (obj->flags & UNINTERESTING) {
1091                        mark_parents_uninteresting(commit);
1092                        if (revs->show_all)
1093                                p = &commit_list_insert(commit, p)->next;
1094                        slop = still_interesting(list, date, slop);
1095                        if (slop)
1096                                continue;
1097                        /* If showing all, add the whole pending list to the end */
1098                        if (revs->show_all)
1099                                *p = list;
1100                        break;
1101                }
1102                if (revs->min_age != -1 && (commit->date > revs->min_age))
1103                        continue;
1104                date = commit->date;
1105                p = &commit_list_insert(commit, p)->next;
1106
1107                show = show_early_output;
1108                if (!show)
1109                        continue;
1110
1111                show(revs, newlist);
1112                show_early_output = NULL;
1113        }
1114        if (revs->cherry_pick || revs->cherry_mark)
1115                cherry_pick_list(newlist, revs);
1116
1117        if (revs->left_only || revs->right_only)
1118                limit_left_right(newlist, revs);
1119
1120        if (bottom) {
1121                limit_to_ancestry(bottom, newlist);
1122                free_commit_list(bottom);
1123        }
1124
1125        /*
1126         * Check if any commits have become TREESAME by some of their parents
1127         * becoming UNINTERESTING.
1128         */
1129        if (limiting_can_increase_treesame(revs))
1130                for (list = newlist; list; list = list->next) {
1131                        struct commit *c = list->item;
1132                        if (c->object.flags & (UNINTERESTING | TREESAME))
1133                                continue;
1134                        update_treesame(revs, c);
1135                }
1136
1137        revs->commits = newlist;
1138        return 0;
1139}
1140
1141/*
1142 * Add an entry to refs->cmdline with the specified information.
1143 * *name is copied.
1144 */
1145static void add_rev_cmdline(struct rev_info *revs,
1146                            struct object *item,
1147                            const char *name,
1148                            int whence,
1149                            unsigned flags)
1150{
1151        struct rev_cmdline_info *info = &revs->cmdline;
1152        int nr = info->nr;
1153
1154        ALLOC_GROW(info->rev, nr + 1, info->alloc);
1155        info->rev[nr].item = item;
1156        info->rev[nr].name = xstrdup(name);
1157        info->rev[nr].whence = whence;
1158        info->rev[nr].flags = flags;
1159        info->nr++;
1160}
1161
1162static void add_rev_cmdline_list(struct rev_info *revs,
1163                                 struct commit_list *commit_list,
1164                                 int whence,
1165                                 unsigned flags)
1166{
1167        while (commit_list) {
1168                struct object *object = &commit_list->item->object;
1169                add_rev_cmdline(revs, object, sha1_to_hex(object->sha1),
1170                                whence, flags);
1171                commit_list = commit_list->next;
1172        }
1173}
1174
1175struct all_refs_cb {
1176        int all_flags;
1177        int warned_bad_reflog;
1178        struct rev_info *all_revs;
1179        const char *name_for_errormsg;
1180};
1181
1182int ref_excluded(struct string_list *ref_excludes, const char *path)
1183{
1184        struct string_list_item *item;
1185
1186        if (!ref_excludes)
1187                return 0;
1188        for_each_string_list_item(item, ref_excludes) {
1189                if (!wildmatch(item->string, path, 0, NULL))
1190                        return 1;
1191        }
1192        return 0;
1193}
1194
1195static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1196{
1197        struct all_refs_cb *cb = cb_data;
1198        struct object *object;
1199
1200        if (ref_excluded(cb->all_revs->ref_excludes, path))
1201            return 0;
1202
1203        object = get_reference(cb->all_revs, path, sha1, cb->all_flags);
1204        add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
1205        add_pending_sha1(cb->all_revs, path, sha1, cb->all_flags);
1206        return 0;
1207}
1208
1209static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
1210        unsigned flags)
1211{
1212        cb->all_revs = revs;
1213        cb->all_flags = flags;
1214}
1215
1216void clear_ref_exclusion(struct string_list **ref_excludes_p)
1217{
1218        if (*ref_excludes_p) {
1219                string_list_clear(*ref_excludes_p, 0);
1220                free(*ref_excludes_p);
1221        }
1222        *ref_excludes_p = NULL;
1223}
1224
1225void add_ref_exclusion(struct string_list **ref_excludes_p, const char *exclude)
1226{
1227        if (!*ref_excludes_p) {
1228                *ref_excludes_p = xcalloc(1, sizeof(**ref_excludes_p));
1229                (*ref_excludes_p)->strdup_strings = 1;
1230        }
1231        string_list_append(*ref_excludes_p, exclude);
1232}
1233
1234static void handle_refs(const char *submodule, struct rev_info *revs, unsigned flags,
1235                int (*for_each)(const char *, each_ref_fn, void *))
1236{
1237        struct all_refs_cb cb;
1238        init_all_refs_cb(&cb, revs, flags);
1239        for_each(submodule, handle_one_ref, &cb);
1240}
1241
1242static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
1243{
1244        struct all_refs_cb *cb = cb_data;
1245        if (!is_null_sha1(sha1)) {
1246                struct object *o = parse_object(sha1);
1247                if (o) {
1248                        o->flags |= cb->all_flags;
1249                        /* ??? CMDLINEFLAGS ??? */
1250                        add_pending_object(cb->all_revs, o, "");
1251                }
1252                else if (!cb->warned_bad_reflog) {
1253                        warning("reflog of '%s' references pruned commits",
1254                                cb->name_for_errormsg);
1255                        cb->warned_bad_reflog = 1;
1256                }
1257        }
1258}
1259
1260static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
1261                const char *email, unsigned long timestamp, int tz,
1262                const char *message, void *cb_data)
1263{
1264        handle_one_reflog_commit(osha1, cb_data);
1265        handle_one_reflog_commit(nsha1, cb_data);
1266        return 0;
1267}
1268
1269static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1270{
1271        struct all_refs_cb *cb = cb_data;
1272        cb->warned_bad_reflog = 0;
1273        cb->name_for_errormsg = path;
1274        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
1275        return 0;
1276}
1277
1278static void handle_reflog(struct rev_info *revs, unsigned flags)
1279{
1280        struct all_refs_cb cb;
1281        cb.all_revs = revs;
1282        cb.all_flags = flags;
1283        for_each_reflog(handle_one_reflog, &cb);
1284}
1285
1286static int add_parents_only(struct rev_info *revs, const char *arg_, int flags)
1287{
1288        unsigned char sha1[20];
1289        struct object *it;
1290        struct commit *commit;
1291        struct commit_list *parents;
1292        const char *arg = arg_;
1293
1294        if (*arg == '^') {
1295                flags ^= UNINTERESTING | BOTTOM;
1296                arg++;
1297        }
1298        if (get_sha1_committish(arg, sha1))
1299                return 0;
1300        while (1) {
1301                it = get_reference(revs, arg, sha1, 0);
1302                if (!it && revs->ignore_missing)
1303                        return 0;
1304                if (it->type != OBJ_TAG)
1305                        break;
1306                if (!((struct tag*)it)->tagged)
1307                        return 0;
1308                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
1309        }
1310        if (it->type != OBJ_COMMIT)
1311                return 0;
1312        commit = (struct commit *)it;
1313        for (parents = commit->parents; parents; parents = parents->next) {
1314                it = &parents->item->object;
1315                it->flags |= flags;
1316                add_rev_cmdline(revs, it, arg_, REV_CMD_PARENTS_ONLY, flags);
1317                add_pending_object(revs, it, arg);
1318        }
1319        return 1;
1320}
1321
1322void init_revisions(struct rev_info *revs, const char *prefix)
1323{
1324        memset(revs, 0, sizeof(*revs));
1325
1326        revs->abbrev = DEFAULT_ABBREV;
1327        revs->ignore_merges = 1;
1328        revs->simplify_history = 1;
1329        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
1330        DIFF_OPT_SET(&revs->pruning, QUICK);
1331        revs->pruning.add_remove = file_add_remove;
1332        revs->pruning.change = file_change;
1333        revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1334        revs->dense = 1;
1335        revs->prefix = prefix;
1336        revs->max_age = -1;
1337        revs->min_age = -1;
1338        revs->skip_count = -1;
1339        revs->max_count = -1;
1340        revs->max_parents = -1;
1341
1342        revs->commit_format = CMIT_FMT_DEFAULT;
1343
1344        init_grep_defaults();
1345        grep_init(&revs->grep_filter, prefix);
1346        revs->grep_filter.status_only = 1;
1347        revs->grep_filter.regflags = REG_NEWLINE;
1348
1349        diff_setup(&revs->diffopt);
1350        if (prefix && !revs->diffopt.prefix) {
1351                revs->diffopt.prefix = prefix;
1352                revs->diffopt.prefix_length = strlen(prefix);
1353        }
1354
1355        revs->notes_opt.use_default_notes = -1;
1356}
1357
1358static void add_pending_commit_list(struct rev_info *revs,
1359                                    struct commit_list *commit_list,
1360                                    unsigned int flags)
1361{
1362        while (commit_list) {
1363                struct object *object = &commit_list->item->object;
1364                object->flags |= flags;
1365                add_pending_object(revs, object, sha1_to_hex(object->sha1));
1366                commit_list = commit_list->next;
1367        }
1368}
1369
1370static void prepare_show_merge(struct rev_info *revs)
1371{
1372        struct commit_list *bases;
1373        struct commit *head, *other;
1374        unsigned char sha1[20];
1375        const char **prune = NULL;
1376        int i, prune_num = 1; /* counting terminating NULL */
1377
1378        if (get_sha1("HEAD", sha1))
1379                die("--merge without HEAD?");
1380        head = lookup_commit_or_die(sha1, "HEAD");
1381        if (get_sha1("MERGE_HEAD", sha1))
1382                die("--merge without MERGE_HEAD?");
1383        other = lookup_commit_or_die(sha1, "MERGE_HEAD");
1384        add_pending_object(revs, &head->object, "HEAD");
1385        add_pending_object(revs, &other->object, "MERGE_HEAD");
1386        bases = get_merge_bases(head, other, 1);
1387        add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
1388        add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
1389        free_commit_list(bases);
1390        head->object.flags |= SYMMETRIC_LEFT;
1391
1392        if (!active_nr)
1393                read_cache();
1394        for (i = 0; i < active_nr; i++) {
1395                const struct cache_entry *ce = active_cache[i];
1396                if (!ce_stage(ce))
1397                        continue;
1398                if (ce_path_match(ce, &revs->prune_data, NULL)) {
1399                        prune_num++;
1400                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
1401                        prune[prune_num-2] = ce->name;
1402                        prune[prune_num-1] = NULL;
1403                }
1404                while ((i+1 < active_nr) &&
1405                       ce_same_name(ce, active_cache[i+1]))
1406                        i++;
1407        }
1408        free_pathspec(&revs->prune_data);
1409        parse_pathspec(&revs->prune_data, PATHSPEC_ALL_MAGIC & ~PATHSPEC_LITERAL,
1410                       PATHSPEC_PREFER_FULL | PATHSPEC_LITERAL_PATH, "", prune);
1411        revs->limited = 1;
1412}
1413
1414int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags, unsigned revarg_opt)
1415{
1416        struct object_context oc;
1417        char *dotdot;
1418        struct object *object;
1419        unsigned char sha1[20];
1420        int local_flags;
1421        const char *arg = arg_;
1422        int cant_be_filename = revarg_opt & REVARG_CANNOT_BE_FILENAME;
1423        unsigned get_sha1_flags = 0;
1424
1425        flags = flags & UNINTERESTING ? flags | BOTTOM : flags & ~BOTTOM;
1426
1427        dotdot = strstr(arg, "..");
1428        if (dotdot) {
1429                unsigned char from_sha1[20];
1430                const char *next = dotdot + 2;
1431                const char *this = arg;
1432                int symmetric = *next == '.';
1433                unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
1434                static const char head_by_default[] = "HEAD";
1435                unsigned int a_flags;
1436
1437                *dotdot = 0;
1438                next += symmetric;
1439
1440                if (!*next)
1441                        next = head_by_default;
1442                if (dotdot == arg)
1443                        this = head_by_default;
1444                if (this == head_by_default && next == head_by_default &&
1445                    !symmetric) {
1446                        /*
1447                         * Just ".."?  That is not a range but the
1448                         * pathspec for the parent directory.
1449                         */
1450                        if (!cant_be_filename) {
1451                                *dotdot = '.';
1452                                return -1;
1453                        }
1454                }
1455                if (!get_sha1_committish(this, from_sha1) &&
1456                    !get_sha1_committish(next, sha1)) {
1457                        struct object *a_obj, *b_obj;
1458
1459                        if (!cant_be_filename) {
1460                                *dotdot = '.';
1461                                verify_non_filename(revs->prefix, arg);
1462                        }
1463
1464                        a_obj = parse_object(from_sha1);
1465                        b_obj = parse_object(sha1);
1466                        if (!a_obj || !b_obj) {
1467                        missing:
1468                                if (revs->ignore_missing)
1469                                        return 0;
1470                                die(symmetric
1471                                    ? "Invalid symmetric difference expression %s"
1472                                    : "Invalid revision range %s", arg);
1473                        }
1474
1475                        if (!symmetric) {
1476                                /* just A..B */
1477                                a_flags = flags_exclude;
1478                        } else {
1479                                /* A...B -- find merge bases between the two */
1480                                struct commit *a, *b;
1481                                struct commit_list *exclude;
1482
1483                                a = (a_obj->type == OBJ_COMMIT
1484                                     ? (struct commit *)a_obj
1485                                     : lookup_commit_reference(a_obj->sha1));
1486                                b = (b_obj->type == OBJ_COMMIT
1487                                     ? (struct commit *)b_obj
1488                                     : lookup_commit_reference(b_obj->sha1));
1489                                if (!a || !b)
1490                                        goto missing;
1491                                exclude = get_merge_bases(a, b, 1);
1492                                add_rev_cmdline_list(revs, exclude,
1493                                                     REV_CMD_MERGE_BASE,
1494                                                     flags_exclude);
1495                                add_pending_commit_list(revs, exclude,
1496                                                        flags_exclude);
1497                                free_commit_list(exclude);
1498
1499                                a_flags = flags | SYMMETRIC_LEFT;
1500                        }
1501
1502                        a_obj->flags |= a_flags;
1503                        b_obj->flags |= flags;
1504                        add_rev_cmdline(revs, a_obj, this,
1505                                        REV_CMD_LEFT, a_flags);
1506                        add_rev_cmdline(revs, b_obj, next,
1507                                        REV_CMD_RIGHT, flags);
1508                        add_pending_object(revs, a_obj, this);
1509                        add_pending_object(revs, b_obj, next);
1510                        return 0;
1511                }
1512                *dotdot = '.';
1513        }
1514        dotdot = strstr(arg, "^@");
1515        if (dotdot && !dotdot[2]) {
1516                *dotdot = 0;
1517                if (add_parents_only(revs, arg, flags))
1518                        return 0;
1519                *dotdot = '^';
1520        }
1521        dotdot = strstr(arg, "^!");
1522        if (dotdot && !dotdot[2]) {
1523                *dotdot = 0;
1524                if (!add_parents_only(revs, arg, flags ^ (UNINTERESTING | BOTTOM)))
1525                        *dotdot = '^';
1526        }
1527
1528        local_flags = 0;
1529        if (*arg == '^') {
1530                local_flags = UNINTERESTING | BOTTOM;
1531                arg++;
1532        }
1533
1534        if (revarg_opt & REVARG_COMMITTISH)
1535                get_sha1_flags = GET_SHA1_COMMITTISH;
1536
1537        if (get_sha1_with_context(arg, get_sha1_flags, sha1, &oc))
1538                return revs->ignore_missing ? 0 : -1;
1539        if (!cant_be_filename)
1540                verify_non_filename(revs->prefix, arg);
1541        object = get_reference(revs, arg, sha1, flags ^ local_flags);
1542        add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
1543        add_pending_object_with_mode(revs, object, arg, oc.mode);
1544        return 0;
1545}
1546
1547struct cmdline_pathspec {
1548        int alloc;
1549        int nr;
1550        const char **path;
1551};
1552
1553static void append_prune_data(struct cmdline_pathspec *prune, const char **av)
1554{
1555        while (*av) {
1556                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1557                prune->path[prune->nr++] = *(av++);
1558        }
1559}
1560
1561static void read_pathspec_from_stdin(struct rev_info *revs, struct strbuf *sb,
1562                                     struct cmdline_pathspec *prune)
1563{
1564        while (strbuf_getwholeline(sb, stdin, '\n') != EOF) {
1565                int len = sb->len;
1566                if (len && sb->buf[len - 1] == '\n')
1567                        sb->buf[--len] = '\0';
1568                ALLOC_GROW(prune->path, prune->nr + 1, prune->alloc);
1569                prune->path[prune->nr++] = xstrdup(sb->buf);
1570        }
1571}
1572
1573static void read_revisions_from_stdin(struct rev_info *revs,
1574                                      struct cmdline_pathspec *prune)
1575{
1576        struct strbuf sb;
1577        int seen_dashdash = 0;
1578
1579        strbuf_init(&sb, 1000);
1580        while (strbuf_getwholeline(&sb, stdin, '\n') != EOF) {
1581                int len = sb.len;
1582                if (len && sb.buf[len - 1] == '\n')
1583                        sb.buf[--len] = '\0';
1584                if (!len)
1585                        break;
1586                if (sb.buf[0] == '-') {
1587                        if (len == 2 && sb.buf[1] == '-') {
1588                                seen_dashdash = 1;
1589                                break;
1590                        }
1591                        die("options not supported in --stdin mode");
1592                }
1593                if (handle_revision_arg(sb.buf, revs, 0,
1594                                        REVARG_CANNOT_BE_FILENAME))
1595                        die("bad revision '%s'", sb.buf);
1596        }
1597        if (seen_dashdash)
1598                read_pathspec_from_stdin(revs, &sb, prune);
1599        strbuf_release(&sb);
1600}
1601
1602static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
1603{
1604        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
1605}
1606
1607static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
1608{
1609        append_header_grep_pattern(&revs->grep_filter, field, pattern);
1610}
1611
1612static void add_message_grep(struct rev_info *revs, const char *pattern)
1613{
1614        add_grep(revs, pattern, GREP_PATTERN_BODY);
1615}
1616
1617static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
1618                               int *unkc, const char **unkv)
1619{
1620        const char *arg = argv[0];
1621        const char *optarg;
1622        int argcount;
1623
1624        /* pseudo revision arguments */
1625        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1626            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1627            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1628            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
1629            !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
1630            starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
1631            starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
1632        {
1633                unkv[(*unkc)++] = arg;
1634                return 1;
1635        }
1636
1637        if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
1638                revs->max_count = atoi(optarg);
1639                revs->no_walk = 0;
1640                return argcount;
1641        } else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
1642                revs->skip_count = atoi(optarg);
1643                return argcount;
1644        } else if ((*arg == '-') && isdigit(arg[1])) {
1645        /* accept -<digit>, like traditional "head" */
1646                revs->max_count = atoi(arg + 1);
1647                revs->no_walk = 0;
1648        } else if (!strcmp(arg, "-n")) {
1649                if (argc <= 1)
1650                        return error("-n requires an argument");
1651                revs->max_count = atoi(argv[1]);
1652                revs->no_walk = 0;
1653                return 2;
1654        } else if (starts_with(arg, "-n")) {
1655                revs->max_count = atoi(arg + 2);
1656                revs->no_walk = 0;
1657        } else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
1658                revs->max_age = atoi(optarg);
1659                return argcount;
1660        } else if ((argcount = parse_long_opt("since", argv, &optarg))) {
1661                revs->max_age = approxidate(optarg);
1662                return argcount;
1663        } else if ((argcount = parse_long_opt("after", argv, &optarg))) {
1664                revs->max_age = approxidate(optarg);
1665                return argcount;
1666        } else if ((argcount = parse_long_opt("min-age", argv, &optarg))) {
1667                revs->min_age = atoi(optarg);
1668                return argcount;
1669        } else if ((argcount = parse_long_opt("before", argv, &optarg))) {
1670                revs->min_age = approxidate(optarg);
1671                return argcount;
1672        } else if ((argcount = parse_long_opt("until", argv, &optarg))) {
1673                revs->min_age = approxidate(optarg);
1674                return argcount;
1675        } else if (!strcmp(arg, "--first-parent")) {
1676                revs->first_parent_only = 1;
1677        } else if (!strcmp(arg, "--ancestry-path")) {
1678                revs->ancestry_path = 1;
1679                revs->simplify_history = 0;
1680                revs->limited = 1;
1681        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1682                init_reflog_walk(&revs->reflog_info);
1683        } else if (!strcmp(arg, "--default")) {
1684                if (argc <= 1)
1685                        return error("bad --default argument");
1686                revs->def = argv[1];
1687                return 2;
1688        } else if (!strcmp(arg, "--merge")) {
1689                revs->show_merge = 1;
1690        } else if (!strcmp(arg, "--topo-order")) {
1691                revs->sort_order = REV_SORT_IN_GRAPH_ORDER;
1692                revs->topo_order = 1;
1693        } else if (!strcmp(arg, "--simplify-merges")) {
1694                revs->simplify_merges = 1;
1695                revs->topo_order = 1;
1696                revs->rewrite_parents = 1;
1697                revs->simplify_history = 0;
1698                revs->limited = 1;
1699        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1700                revs->simplify_merges = 1;
1701                revs->topo_order = 1;
1702                revs->rewrite_parents = 1;
1703                revs->simplify_history = 0;
1704                revs->simplify_by_decoration = 1;
1705                revs->limited = 1;
1706                revs->prune = 1;
1707                load_ref_decorations(DECORATE_SHORT_REFS);
1708        } else if (!strcmp(arg, "--date-order")) {
1709                revs->sort_order = REV_SORT_BY_COMMIT_DATE;
1710                revs->topo_order = 1;
1711        } else if (!strcmp(arg, "--author-date-order")) {
1712                revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
1713                revs->topo_order = 1;
1714        } else if (starts_with(arg, "--early-output")) {
1715                int count = 100;
1716                switch (arg[14]) {
1717                case '=':
1718                        count = atoi(arg+15);
1719                        /* Fallthrough */
1720                case 0:
1721                        revs->topo_order = 1;
1722                       revs->early_output = count;
1723                }
1724        } else if (!strcmp(arg, "--parents")) {
1725                revs->rewrite_parents = 1;
1726                revs->print_parents = 1;
1727        } else if (!strcmp(arg, "--dense")) {
1728                revs->dense = 1;
1729        } else if (!strcmp(arg, "--sparse")) {
1730                revs->dense = 0;
1731        } else if (!strcmp(arg, "--show-all")) {
1732                revs->show_all = 1;
1733        } else if (!strcmp(arg, "--remove-empty")) {
1734                revs->remove_empty_trees = 1;
1735        } else if (!strcmp(arg, "--merges")) {
1736                revs->min_parents = 2;
1737        } else if (!strcmp(arg, "--no-merges")) {
1738                revs->max_parents = 1;
1739        } else if (starts_with(arg, "--min-parents=")) {
1740                revs->min_parents = atoi(arg+14);
1741        } else if (starts_with(arg, "--no-min-parents")) {
1742                revs->min_parents = 0;
1743        } else if (starts_with(arg, "--max-parents=")) {
1744                revs->max_parents = atoi(arg+14);
1745        } else if (starts_with(arg, "--no-max-parents")) {
1746                revs->max_parents = -1;
1747        } else if (!strcmp(arg, "--boundary")) {
1748                revs->boundary = 1;
1749        } else if (!strcmp(arg, "--left-right")) {
1750                revs->left_right = 1;
1751        } else if (!strcmp(arg, "--left-only")) {
1752                if (revs->right_only)
1753                        die("--left-only is incompatible with --right-only"
1754                            " or --cherry");
1755                revs->left_only = 1;
1756        } else if (!strcmp(arg, "--right-only")) {
1757                if (revs->left_only)
1758                        die("--right-only is incompatible with --left-only");
1759                revs->right_only = 1;
1760        } else if (!strcmp(arg, "--cherry")) {
1761                if (revs->left_only)
1762                        die("--cherry is incompatible with --left-only");
1763                revs->cherry_mark = 1;
1764                revs->right_only = 1;
1765                revs->max_parents = 1;
1766                revs->limited = 1;
1767        } else if (!strcmp(arg, "--count")) {
1768                revs->count = 1;
1769        } else if (!strcmp(arg, "--cherry-mark")) {
1770                if (revs->cherry_pick)
1771                        die("--cherry-mark is incompatible with --cherry-pick");
1772                revs->cherry_mark = 1;
1773                revs->limited = 1; /* needs limit_list() */
1774        } else if (!strcmp(arg, "--cherry-pick")) {
1775                if (revs->cherry_mark)
1776                        die("--cherry-pick is incompatible with --cherry-mark");
1777                revs->cherry_pick = 1;
1778                revs->limited = 1;
1779        } else if (!strcmp(arg, "--objects")) {
1780                revs->tag_objects = 1;
1781                revs->tree_objects = 1;
1782                revs->blob_objects = 1;
1783        } else if (!strcmp(arg, "--objects-edge")) {
1784                revs->tag_objects = 1;
1785                revs->tree_objects = 1;
1786                revs->blob_objects = 1;
1787                revs->edge_hint = 1;
1788        } else if (!strcmp(arg, "--verify-objects")) {
1789                revs->tag_objects = 1;
1790                revs->tree_objects = 1;
1791                revs->blob_objects = 1;
1792                revs->verify_objects = 1;
1793        } else if (!strcmp(arg, "--unpacked")) {
1794                revs->unpacked = 1;
1795        } else if (starts_with(arg, "--unpacked=")) {
1796                die("--unpacked=<packfile> no longer supported.");
1797        } else if (!strcmp(arg, "-r")) {
1798                revs->diff = 1;
1799                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1800        } else if (!strcmp(arg, "-t")) {
1801                revs->diff = 1;
1802                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1803                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1804        } else if (!strcmp(arg, "-m")) {
1805                revs->ignore_merges = 0;
1806        } else if (!strcmp(arg, "-c")) {
1807                revs->diff = 1;
1808                revs->dense_combined_merges = 0;
1809                revs->combine_merges = 1;
1810        } else if (!strcmp(arg, "--cc")) {
1811                revs->diff = 1;
1812                revs->dense_combined_merges = 1;
1813                revs->combine_merges = 1;
1814        } else if (!strcmp(arg, "-v")) {
1815                revs->verbose_header = 1;
1816        } else if (!strcmp(arg, "--pretty")) {
1817                revs->verbose_header = 1;
1818                revs->pretty_given = 1;
1819                get_commit_format(arg+8, revs);
1820        } else if (starts_with(arg, "--pretty=") || starts_with(arg, "--format=")) {
1821                /*
1822                 * Detached form ("--pretty X" as opposed to "--pretty=X")
1823                 * not allowed, since the argument is optional.
1824                 */
1825                revs->verbose_header = 1;
1826                revs->pretty_given = 1;
1827                get_commit_format(arg+9, revs);
1828        } else if (!strcmp(arg, "--show-notes") || !strcmp(arg, "--notes")) {
1829                revs->show_notes = 1;
1830                revs->show_notes_given = 1;
1831                revs->notes_opt.use_default_notes = 1;
1832        } else if (!strcmp(arg, "--show-signature")) {
1833                revs->show_signature = 1;
1834        } else if (starts_with(arg, "--show-notes=") ||
1835                   starts_with(arg, "--notes=")) {
1836                struct strbuf buf = STRBUF_INIT;
1837                revs->show_notes = 1;
1838                revs->show_notes_given = 1;
1839                if (starts_with(arg, "--show-notes")) {
1840                        if (revs->notes_opt.use_default_notes < 0)
1841                                revs->notes_opt.use_default_notes = 1;
1842                        strbuf_addstr(&buf, arg+13);
1843                }
1844                else
1845                        strbuf_addstr(&buf, arg+8);
1846                expand_notes_ref(&buf);
1847                string_list_append(&revs->notes_opt.extra_notes_refs,
1848                                   strbuf_detach(&buf, NULL));
1849        } else if (!strcmp(arg, "--no-notes")) {
1850                revs->show_notes = 0;
1851                revs->show_notes_given = 1;
1852                revs->notes_opt.use_default_notes = -1;
1853                /* we have been strdup'ing ourselves, so trick
1854                 * string_list into free()ing strings */
1855                revs->notes_opt.extra_notes_refs.strdup_strings = 1;
1856                string_list_clear(&revs->notes_opt.extra_notes_refs, 0);
1857                revs->notes_opt.extra_notes_refs.strdup_strings = 0;
1858        } else if (!strcmp(arg, "--standard-notes")) {
1859                revs->show_notes_given = 1;
1860                revs->notes_opt.use_default_notes = 1;
1861        } else if (!strcmp(arg, "--no-standard-notes")) {
1862                revs->notes_opt.use_default_notes = 0;
1863        } else if (!strcmp(arg, "--oneline")) {
1864                revs->verbose_header = 1;
1865                get_commit_format("oneline", revs);
1866                revs->pretty_given = 1;
1867                revs->abbrev_commit = 1;
1868        } else if (!strcmp(arg, "--graph")) {
1869                revs->topo_order = 1;
1870                revs->rewrite_parents = 1;
1871                revs->graph = graph_init(revs);
1872        } else if (!strcmp(arg, "--root")) {
1873                revs->show_root_diff = 1;
1874        } else if (!strcmp(arg, "--no-commit-id")) {
1875                revs->no_commit_id = 1;
1876        } else if (!strcmp(arg, "--always")) {
1877                revs->always_show_header = 1;
1878        } else if (!strcmp(arg, "--no-abbrev")) {
1879                revs->abbrev = 0;
1880        } else if (!strcmp(arg, "--abbrev")) {
1881                revs->abbrev = DEFAULT_ABBREV;
1882        } else if (starts_with(arg, "--abbrev=")) {
1883                revs->abbrev = strtoul(arg + 9, NULL, 10);
1884                if (revs->abbrev < MINIMUM_ABBREV)
1885                        revs->abbrev = MINIMUM_ABBREV;
1886                else if (revs->abbrev > 40)
1887                        revs->abbrev = 40;
1888        } else if (!strcmp(arg, "--abbrev-commit")) {
1889                revs->abbrev_commit = 1;
1890                revs->abbrev_commit_given = 1;
1891        } else if (!strcmp(arg, "--no-abbrev-commit")) {
1892                revs->abbrev_commit = 0;
1893        } else if (!strcmp(arg, "--full-diff")) {
1894                revs->diff = 1;
1895                revs->full_diff = 1;
1896        } else if (!strcmp(arg, "--full-history")) {
1897                revs->simplify_history = 0;
1898        } else if (!strcmp(arg, "--relative-date")) {
1899                revs->date_mode = DATE_RELATIVE;
1900                revs->date_mode_explicit = 1;
1901        } else if ((argcount = parse_long_opt("date", argv, &optarg))) {
1902                revs->date_mode = parse_date_format(optarg);
1903                revs->date_mode_explicit = 1;
1904                return argcount;
1905        } else if (!strcmp(arg, "--log-size")) {
1906                revs->show_log_size = 1;
1907        }
1908        /*
1909         * Grepping the commit log
1910         */
1911        else if ((argcount = parse_long_opt("author", argv, &optarg))) {
1912                add_header_grep(revs, GREP_HEADER_AUTHOR, optarg);
1913                return argcount;
1914        } else if ((argcount = parse_long_opt("committer", argv, &optarg))) {
1915                add_header_grep(revs, GREP_HEADER_COMMITTER, optarg);
1916                return argcount;
1917        } else if ((argcount = parse_long_opt("grep-reflog", argv, &optarg))) {
1918                add_header_grep(revs, GREP_HEADER_REFLOG, optarg);
1919                return argcount;
1920        } else if ((argcount = parse_long_opt("grep", argv, &optarg))) {
1921                add_message_grep(revs, optarg);
1922                return argcount;
1923        } else if (!strcmp(arg, "--grep-debug")) {
1924                revs->grep_filter.debug = 1;
1925        } else if (!strcmp(arg, "--basic-regexp")) {
1926                grep_set_pattern_type_option(GREP_PATTERN_TYPE_BRE, &revs->grep_filter);
1927        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
1928                grep_set_pattern_type_option(GREP_PATTERN_TYPE_ERE, &revs->grep_filter);
1929        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
1930                revs->grep_filter.regflags |= REG_ICASE;
1931                DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
1932        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
1933                grep_set_pattern_type_option(GREP_PATTERN_TYPE_FIXED, &revs->grep_filter);
1934        } else if (!strcmp(arg, "--perl-regexp")) {
1935                grep_set_pattern_type_option(GREP_PATTERN_TYPE_PCRE, &revs->grep_filter);
1936        } else if (!strcmp(arg, "--all-match")) {
1937                revs->grep_filter.all_match = 1;
1938        } else if ((argcount = parse_long_opt("encoding", argv, &optarg))) {
1939                if (strcmp(optarg, "none"))
1940                        git_log_output_encoding = xstrdup(optarg);
1941                else
1942                        git_log_output_encoding = "";
1943                return argcount;
1944        } else if (!strcmp(arg, "--reverse")) {
1945                revs->reverse ^= 1;
1946        } else if (!strcmp(arg, "--children")) {
1947                revs->children.name = "children";
1948                revs->limited = 1;
1949        } else if (!strcmp(arg, "--ignore-missing")) {
1950                revs->ignore_missing = 1;
1951        } else {
1952                int opts = diff_opt_parse(&revs->diffopt, argv, argc);
1953                if (!opts)
1954                        unkv[(*unkc)++] = arg;
1955                return opts;
1956        }
1957
1958        return 1;
1959}
1960
1961void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
1962                        const struct option *options,
1963                        const char * const usagestr[])
1964{
1965        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
1966                                    &ctx->cpidx, ctx->out);
1967        if (n <= 0) {
1968                error("unknown option `%s'", ctx->argv[0]);
1969                usage_with_options(usagestr, options);
1970        }
1971        ctx->argv += n;
1972        ctx->argc -= n;
1973}
1974
1975static int for_each_bad_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1976{
1977        return for_each_ref_in_submodule(submodule, "refs/bisect/bad", fn, cb_data);
1978}
1979
1980static int for_each_good_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1981{
1982        return for_each_ref_in_submodule(submodule, "refs/bisect/good", fn, cb_data);
1983}
1984
1985static int handle_revision_pseudo_opt(const char *submodule,
1986                                struct rev_info *revs,
1987                                int argc, const char **argv, int *flags)
1988{
1989        const char *arg = argv[0];
1990        const char *optarg;
1991        int argcount;
1992
1993        /*
1994         * NOTE!
1995         *
1996         * Commands like "git shortlog" will not accept the options below
1997         * unless parse_revision_opt queues them (as opposed to erroring
1998         * out).
1999         *
2000         * When implementing your new pseudo-option, remember to
2001         * register it in the list at the top of handle_revision_opt.
2002         */
2003        if (!strcmp(arg, "--all")) {
2004                handle_refs(submodule, revs, *flags, for_each_ref_submodule);
2005                handle_refs(submodule, revs, *flags, head_ref_submodule);
2006                clear_ref_exclusion(&revs->ref_excludes);
2007        } else if (!strcmp(arg, "--branches")) {
2008                handle_refs(submodule, revs, *flags, for_each_branch_ref_submodule);
2009                clear_ref_exclusion(&revs->ref_excludes);
2010        } else if (!strcmp(arg, "--bisect")) {
2011                handle_refs(submodule, revs, *flags, for_each_bad_bisect_ref);
2012                handle_refs(submodule, revs, *flags ^ (UNINTERESTING | BOTTOM), for_each_good_bisect_ref);
2013                revs->bisect = 1;
2014        } else if (!strcmp(arg, "--tags")) {
2015                handle_refs(submodule, revs, *flags, for_each_tag_ref_submodule);
2016                clear_ref_exclusion(&revs->ref_excludes);
2017        } else if (!strcmp(arg, "--remotes")) {
2018                handle_refs(submodule, revs, *flags, for_each_remote_ref_submodule);
2019                clear_ref_exclusion(&revs->ref_excludes);
2020        } else if ((argcount = parse_long_opt("glob", argv, &optarg))) {
2021                struct all_refs_cb cb;
2022                init_all_refs_cb(&cb, revs, *flags);
2023                for_each_glob_ref(handle_one_ref, optarg, &cb);
2024                clear_ref_exclusion(&revs->ref_excludes);
2025                return argcount;
2026        } else if ((argcount = parse_long_opt("exclude", argv, &optarg))) {
2027                add_ref_exclusion(&revs->ref_excludes, optarg);
2028                return argcount;
2029        } else if (starts_with(arg, "--branches=")) {
2030                struct all_refs_cb cb;
2031                init_all_refs_cb(&cb, revs, *flags);
2032                for_each_glob_ref_in(handle_one_ref, arg + 11, "refs/heads/", &cb);
2033                clear_ref_exclusion(&revs->ref_excludes);
2034        } else if (starts_with(arg, "--tags=")) {
2035                struct all_refs_cb cb;
2036                init_all_refs_cb(&cb, revs, *flags);
2037                for_each_glob_ref_in(handle_one_ref, arg + 7, "refs/tags/", &cb);
2038                clear_ref_exclusion(&revs->ref_excludes);
2039        } else if (starts_with(arg, "--remotes=")) {
2040                struct all_refs_cb cb;
2041                init_all_refs_cb(&cb, revs, *flags);
2042                for_each_glob_ref_in(handle_one_ref, arg + 10, "refs/remotes/", &cb);
2043                clear_ref_exclusion(&revs->ref_excludes);
2044        } else if (!strcmp(arg, "--reflog")) {
2045                handle_reflog(revs, *flags);
2046        } else if (!strcmp(arg, "--not")) {
2047                *flags ^= UNINTERESTING | BOTTOM;
2048        } else if (!strcmp(arg, "--no-walk")) {
2049                revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2050        } else if (starts_with(arg, "--no-walk=")) {
2051                /*
2052                 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
2053                 * not allowed, since the argument is optional.
2054                 */
2055                if (!strcmp(arg + 10, "sorted"))
2056                        revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
2057                else if (!strcmp(arg + 10, "unsorted"))
2058                        revs->no_walk = REVISION_WALK_NO_WALK_UNSORTED;
2059                else
2060                        return error("invalid argument to --no-walk");
2061        } else if (!strcmp(arg, "--do-walk")) {
2062                revs->no_walk = 0;
2063        } else {
2064                return 0;
2065        }
2066
2067        return 1;
2068}
2069
2070/*
2071 * Parse revision information, filling in the "rev_info" structure,
2072 * and removing the used arguments from the argument list.
2073 *
2074 * Returns the number of arguments left that weren't recognized
2075 * (which are also moved to the head of the argument list)
2076 */
2077int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct setup_revision_opt *opt)
2078{
2079        int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0, revarg_opt;
2080        struct cmdline_pathspec prune_data;
2081        const char *submodule = NULL;
2082
2083        memset(&prune_data, 0, sizeof(prune_data));
2084        if (opt)
2085                submodule = opt->submodule;
2086
2087        /* First, search for "--" */
2088        if (opt && opt->assume_dashdash) {
2089                seen_dashdash = 1;
2090        } else {
2091                seen_dashdash = 0;
2092                for (i = 1; i < argc; i++) {
2093                        const char *arg = argv[i];
2094                        if (strcmp(arg, "--"))
2095                                continue;
2096                        argv[i] = NULL;
2097                        argc = i;
2098                        if (argv[i + 1])
2099                                append_prune_data(&prune_data, argv + i + 1);
2100                        seen_dashdash = 1;
2101                        break;
2102                }
2103        }
2104
2105        /* Second, deal with arguments and options */
2106        flags = 0;
2107        revarg_opt = opt ? opt->revarg_opt : 0;
2108        if (seen_dashdash)
2109                revarg_opt |= REVARG_CANNOT_BE_FILENAME;
2110        read_from_stdin = 0;
2111        for (left = i = 1; i < argc; i++) {
2112                const char *arg = argv[i];
2113                if (*arg == '-') {
2114                        int opts;
2115
2116                        opts = handle_revision_pseudo_opt(submodule,
2117                                                revs, argc - i, argv + i,
2118                                                &flags);
2119                        if (opts > 0) {
2120                                i += opts - 1;
2121                                continue;
2122                        }
2123
2124                        if (!strcmp(arg, "--stdin")) {
2125                                if (revs->disable_stdin) {
2126                                        argv[left++] = arg;
2127                                        continue;
2128                                }
2129                                if (read_from_stdin++)
2130                                        die("--stdin given twice?");
2131                                read_revisions_from_stdin(revs, &prune_data);
2132                                continue;
2133                        }
2134
2135                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
2136                        if (opts > 0) {
2137                                i += opts - 1;
2138                                continue;
2139                        }
2140                        if (opts < 0)
2141                                exit(128);
2142                        continue;
2143                }
2144
2145
2146                if (handle_revision_arg(arg, revs, flags, revarg_opt)) {
2147                        int j;
2148                        if (seen_dashdash || *arg == '^')
2149                                die("bad revision '%s'", arg);
2150
2151                        /* If we didn't have a "--":
2152                         * (1) all filenames must exist;
2153                         * (2) all rev-args must not be interpretable
2154                         *     as a valid filename.
2155                         * but the latter we have checked in the main loop.
2156                         */
2157                        for (j = i; j < argc; j++)
2158                                verify_filename(revs->prefix, argv[j], j == i);
2159
2160                        append_prune_data(&prune_data, argv + i);
2161                        break;
2162                }
2163                else
2164                        got_rev_arg = 1;
2165        }
2166
2167        if (prune_data.nr) {
2168                /*
2169                 * If we need to introduce the magic "a lone ':' means no
2170                 * pathspec whatsoever", here is the place to do so.
2171                 *
2172                 * if (prune_data.nr == 1 && !strcmp(prune_data[0], ":")) {
2173                 *      prune_data.nr = 0;
2174                 *      prune_data.alloc = 0;
2175                 *      free(prune_data.path);
2176                 *      prune_data.path = NULL;
2177                 * } else {
2178                 *      terminate prune_data.alloc with NULL and
2179                 *      call init_pathspec() to set revs->prune_data here.
2180                 * }
2181                 */
2182                ALLOC_GROW(prune_data.path, prune_data.nr + 1, prune_data.alloc);
2183                prune_data.path[prune_data.nr++] = NULL;
2184                parse_pathspec(&revs->prune_data, 0, 0,
2185                               revs->prefix, prune_data.path);
2186        }
2187
2188        if (revs->def == NULL)
2189                revs->def = opt ? opt->def : NULL;
2190        if (opt && opt->tweak)
2191                opt->tweak(revs, opt);
2192        if (revs->show_merge)
2193                prepare_show_merge(revs);
2194        if (revs->def && !revs->pending.nr && !got_rev_arg) {
2195                unsigned char sha1[20];
2196                struct object *object;
2197                struct object_context oc;
2198                if (get_sha1_with_context(revs->def, 0, sha1, &oc))
2199                        die("bad default revision '%s'", revs->def);
2200                object = get_reference(revs, revs->def, sha1, 0);
2201                add_pending_object_with_mode(revs, object, revs->def, oc.mode);
2202        }
2203
2204        /* Did the user ask for any diff output? Run the diff! */
2205        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
2206                revs->diff = 1;
2207
2208        /* Pickaxe, diff-filter and rename following need diffs */
2209        if (revs->diffopt.pickaxe ||
2210            revs->diffopt.filter ||
2211            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2212                revs->diff = 1;
2213
2214        if (revs->topo_order)
2215                revs->limited = 1;
2216
2217        if (revs->prune_data.nr) {
2218                copy_pathspec(&revs->pruning.pathspec, &revs->prune_data);
2219                /* Can't prune commits with rename following: the paths change.. */
2220                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
2221                        revs->prune = 1;
2222                if (!revs->full_diff)
2223                        copy_pathspec(&revs->diffopt.pathspec,
2224                                      &revs->prune_data);
2225        }
2226        if (revs->combine_merges)
2227                revs->ignore_merges = 0;
2228        revs->diffopt.abbrev = revs->abbrev;
2229
2230        if (revs->line_level_traverse) {
2231                revs->limited = 1;
2232                revs->topo_order = 1;
2233        }
2234
2235        diff_setup_done(&revs->diffopt);
2236
2237        grep_commit_pattern_type(GREP_PATTERN_TYPE_UNSPECIFIED,
2238                                 &revs->grep_filter);
2239        compile_grep_patterns(&revs->grep_filter);
2240
2241        if (revs->reverse && revs->reflog_info)
2242                die("cannot combine --reverse with --walk-reflogs");
2243        if (revs->rewrite_parents && revs->children.name)
2244                die("cannot combine --parents and --children");
2245
2246        /*
2247         * Limitations on the graph functionality
2248         */
2249        if (revs->reverse && revs->graph)
2250                die("cannot combine --reverse with --graph");
2251
2252        if (revs->reflog_info && revs->graph)
2253                die("cannot combine --walk-reflogs with --graph");
2254        if (!revs->reflog_info && revs->grep_filter.use_reflog_filter)
2255                die("cannot use --grep-reflog without --walk-reflogs");
2256
2257        return left;
2258}
2259
2260static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
2261{
2262        struct commit_list *l = xcalloc(1, sizeof(*l));
2263
2264        l->item = child;
2265        l->next = add_decoration(&revs->children, &parent->object, l);
2266}
2267
2268static int remove_duplicate_parents(struct rev_info *revs, struct commit *commit)
2269{
2270        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2271        struct commit_list **pp, *p;
2272        int surviving_parents;
2273
2274        /* Examine existing parents while marking ones we have seen... */
2275        pp = &commit->parents;
2276        surviving_parents = 0;
2277        while ((p = *pp) != NULL) {
2278                struct commit *parent = p->item;
2279                if (parent->object.flags & TMP_MARK) {
2280                        *pp = p->next;
2281                        if (ts)
2282                                compact_treesame(revs, commit, surviving_parents);
2283                        continue;
2284                }
2285                parent->object.flags |= TMP_MARK;
2286                surviving_parents++;
2287                pp = &p->next;
2288        }
2289        /* clear the temporary mark */
2290        for (p = commit->parents; p; p = p->next) {
2291                p->item->object.flags &= ~TMP_MARK;
2292        }
2293        /* no update_treesame() - removing duplicates can't affect TREESAME */
2294        return surviving_parents;
2295}
2296
2297struct merge_simplify_state {
2298        struct commit *simplified;
2299};
2300
2301static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
2302{
2303        struct merge_simplify_state *st;
2304
2305        st = lookup_decoration(&revs->merge_simplification, &commit->object);
2306        if (!st) {
2307                st = xcalloc(1, sizeof(*st));
2308                add_decoration(&revs->merge_simplification, &commit->object, st);
2309        }
2310        return st;
2311}
2312
2313static int mark_redundant_parents(struct rev_info *revs, struct commit *commit)
2314{
2315        struct commit_list *h = reduce_heads(commit->parents);
2316        int i = 0, marked = 0;
2317        struct commit_list *po, *pn;
2318
2319        /* Want these for sanity-checking only */
2320        int orig_cnt = commit_list_count(commit->parents);
2321        int cnt = commit_list_count(h);
2322
2323        /*
2324         * Not ready to remove items yet, just mark them for now, based
2325         * on the output of reduce_heads(). reduce_heads outputs the reduced
2326         * set in its original order, so this isn't too hard.
2327         */
2328        po = commit->parents;
2329        pn = h;
2330        while (po) {
2331                if (pn && po->item == pn->item) {
2332                        pn = pn->next;
2333                        i++;
2334                } else {
2335                        po->item->object.flags |= TMP_MARK;
2336                        marked++;
2337                }
2338                po=po->next;
2339        }
2340
2341        if (i != cnt || cnt+marked != orig_cnt)
2342                die("mark_redundant_parents %d %d %d %d", orig_cnt, cnt, i, marked);
2343
2344        free_commit_list(h);
2345
2346        return marked;
2347}
2348
2349static int mark_treesame_root_parents(struct rev_info *revs, struct commit *commit)
2350{
2351        struct commit_list *p;
2352        int marked = 0;
2353
2354        for (p = commit->parents; p; p = p->next) {
2355                struct commit *parent = p->item;
2356                if (!parent->parents && (parent->object.flags & TREESAME)) {
2357                        parent->object.flags |= TMP_MARK;
2358                        marked++;
2359                }
2360        }
2361
2362        return marked;
2363}
2364
2365/*
2366 * Awkward naming - this means one parent we are TREESAME to.
2367 * cf mark_treesame_root_parents: root parents that are TREESAME (to an
2368 * empty tree). Better name suggestions?
2369 */
2370static int leave_one_treesame_to_parent(struct rev_info *revs, struct commit *commit)
2371{
2372        struct treesame_state *ts = lookup_decoration(&revs->treesame, &commit->object);
2373        struct commit *unmarked = NULL, *marked = NULL;
2374        struct commit_list *p;
2375        unsigned n;
2376
2377        for (p = commit->parents, n = 0; p; p = p->next, n++) {
2378                if (ts->treesame[n]) {
2379                        if (p->item->object.flags & TMP_MARK) {
2380                                if (!marked)
2381                                        marked = p->item;
2382                        } else {
2383                                if (!unmarked) {
2384                                        unmarked = p->item;
2385                                        break;
2386                                }
2387                        }
2388                }
2389        }
2390
2391        /*
2392         * If we are TREESAME to a marked-for-deletion parent, but not to any
2393         * unmarked parents, unmark the first TREESAME parent. This is the
2394         * parent that the default simplify_history==1 scan would have followed,
2395         * and it doesn't make sense to omit that path when asking for a
2396         * simplified full history. Retaining it improves the chances of
2397         * understanding odd missed merges that took an old version of a file.
2398         *
2399         * Example:
2400         *
2401         *   I--------*X       A modified the file, but mainline merge X used
2402         *    \       /        "-s ours", so took the version from I. X is
2403         *     `-*A--'         TREESAME to I and !TREESAME to A.
2404         *
2405         * Default log from X would produce "I". Without this check,
2406         * --full-history --simplify-merges would produce "I-A-X", showing
2407         * the merge commit X and that it changed A, but not making clear that
2408         * it had just taken the I version. With this check, the topology above
2409         * is retained.
2410         *
2411         * Note that it is possible that the simplification chooses a different
2412         * TREESAME parent from the default, in which case this test doesn't
2413         * activate, and we _do_ drop the default parent. Example:
2414         *
2415         *   I------X         A modified the file, but it was reverted in B,
2416         *    \    /          meaning mainline merge X is TREESAME to both
2417         *    *A-*B           parents.
2418         *
2419         * Default log would produce "I" by following the first parent;
2420         * --full-history --simplify-merges will produce "I-A-B". But this is a
2421         * reasonable result - it presents a logical full history leading from
2422         * I to X, and X is not an important merge.
2423         */
2424        if (!unmarked && marked) {
2425                marked->object.flags &= ~TMP_MARK;
2426                return 1;
2427        }
2428
2429        return 0;
2430}
2431
2432static int remove_marked_parents(struct rev_info *revs, struct commit *commit)
2433{
2434        struct commit_list **pp, *p;
2435        int nth_parent, removed = 0;
2436
2437        pp = &commit->parents;
2438        nth_parent = 0;
2439        while ((p = *pp) != NULL) {
2440                struct commit *parent = p->item;
2441                if (parent->object.flags & TMP_MARK) {
2442                        parent->object.flags &= ~TMP_MARK;
2443                        *pp = p->next;
2444                        free(p);
2445                        removed++;
2446                        compact_treesame(revs, commit, nth_parent);
2447                        continue;
2448                }
2449                pp = &p->next;
2450                nth_parent++;
2451        }
2452
2453        /* Removing parents can only increase TREESAMEness */
2454        if (removed && !(commit->object.flags & TREESAME))
2455                update_treesame(revs, commit);
2456
2457        return nth_parent;
2458}
2459
2460static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
2461{
2462        struct commit_list *p;
2463        struct commit *parent;
2464        struct merge_simplify_state *st, *pst;
2465        int cnt;
2466
2467        st = locate_simplify_state(revs, commit);
2468
2469        /*
2470         * Have we handled this one?
2471         */
2472        if (st->simplified)
2473                return tail;
2474
2475        /*
2476         * An UNINTERESTING commit simplifies to itself, so does a
2477         * root commit.  We do not rewrite parents of such commit
2478         * anyway.
2479         */
2480        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
2481                st->simplified = commit;
2482                return tail;
2483        }
2484
2485        /*
2486         * Do we know what commit all of our parents that matter
2487         * should be rewritten to?  Otherwise we are not ready to
2488         * rewrite this one yet.
2489         */
2490        for (cnt = 0, p = commit->parents; p; p = p->next) {
2491                pst = locate_simplify_state(revs, p->item);
2492                if (!pst->simplified) {
2493                        tail = &commit_list_insert(p->item, tail)->next;
2494                        cnt++;
2495                }
2496                if (revs->first_parent_only)
2497                        break;
2498        }
2499        if (cnt) {
2500                tail = &commit_list_insert(commit, tail)->next;
2501                return tail;
2502        }
2503
2504        /*
2505         * Rewrite our list of parents. Note that this cannot
2506         * affect our TREESAME flags in any way - a commit is
2507         * always TREESAME to its simplification.
2508         */
2509        for (p = commit->parents; p; p = p->next) {
2510                pst = locate_simplify_state(revs, p->item);
2511                p->item = pst->simplified;
2512                if (revs->first_parent_only)
2513                        break;
2514        }
2515
2516        if (revs->first_parent_only)
2517                cnt = 1;
2518        else
2519                cnt = remove_duplicate_parents(revs, commit);
2520
2521        /*
2522         * It is possible that we are a merge and one side branch
2523         * does not have any commit that touches the given paths;
2524         * in such a case, the immediate parent from that branch
2525         * will be rewritten to be the merge base.
2526         *
2527         *      o----X          X: the commit we are looking at;
2528         *     /    /           o: a commit that touches the paths;
2529         * ---o----'
2530         *
2531         * Further, a merge of an independent branch that doesn't
2532         * touch the path will reduce to a treesame root parent:
2533         *
2534         *  ----o----X          X: the commit we are looking at;
2535         *          /           o: a commit that touches the paths;
2536         *         r            r: a root commit not touching the paths
2537         *
2538         * Detect and simplify both cases.
2539         */
2540        if (1 < cnt) {
2541                int marked = mark_redundant_parents(revs, commit);
2542                marked += mark_treesame_root_parents(revs, commit);
2543                if (marked)
2544                        marked -= leave_one_treesame_to_parent(revs, commit);
2545                if (marked)
2546                        cnt = remove_marked_parents(revs, commit);
2547        }
2548
2549        /*
2550         * A commit simplifies to itself if it is a root, if it is
2551         * UNINTERESTING, if it touches the given paths, or if it is a
2552         * merge and its parents don't simplify to one relevant commit
2553         * (the first two cases are already handled at the beginning of
2554         * this function).
2555         *
2556         * Otherwise, it simplifies to what its sole relevant parent
2557         * simplifies to.
2558         */
2559        if (!cnt ||
2560            (commit->object.flags & UNINTERESTING) ||
2561            !(commit->object.flags & TREESAME) ||
2562            (parent = one_relevant_parent(revs, commit->parents)) == NULL)
2563                st->simplified = commit;
2564        else {
2565                pst = locate_simplify_state(revs, parent);
2566                st->simplified = pst->simplified;
2567        }
2568        return tail;
2569}
2570
2571static void simplify_merges(struct rev_info *revs)
2572{
2573        struct commit_list *list, *next;
2574        struct commit_list *yet_to_do, **tail;
2575        struct commit *commit;
2576
2577        if (!revs->prune)
2578                return;
2579
2580        /* feed the list reversed */
2581        yet_to_do = NULL;
2582        for (list = revs->commits; list; list = next) {
2583                commit = list->item;
2584                next = list->next;
2585                /*
2586                 * Do not free(list) here yet; the original list
2587                 * is used later in this function.
2588                 */
2589                commit_list_insert(commit, &yet_to_do);
2590        }
2591        while (yet_to_do) {
2592                list = yet_to_do;
2593                yet_to_do = NULL;
2594                tail = &yet_to_do;
2595                while (list) {
2596                        commit = list->item;
2597                        next = list->next;
2598                        free(list);
2599                        list = next;
2600                        tail = simplify_one(revs, commit, tail);
2601                }
2602        }
2603
2604        /* clean up the result, removing the simplified ones */
2605        list = revs->commits;
2606        revs->commits = NULL;
2607        tail = &revs->commits;
2608        while (list) {
2609                struct merge_simplify_state *st;
2610
2611                commit = list->item;
2612                next = list->next;
2613                free(list);
2614                list = next;
2615                st = locate_simplify_state(revs, commit);
2616                if (st->simplified == commit)
2617                        tail = &commit_list_insert(commit, tail)->next;
2618        }
2619}
2620
2621static void set_children(struct rev_info *revs)
2622{
2623        struct commit_list *l;
2624        for (l = revs->commits; l; l = l->next) {
2625                struct commit *commit = l->item;
2626                struct commit_list *p;
2627
2628                for (p = commit->parents; p; p = p->next)
2629                        add_child(revs, p->item, commit);
2630        }
2631}
2632
2633void reset_revision_walk(void)
2634{
2635        clear_object_flags(SEEN | ADDED | SHOWN);
2636}
2637
2638int prepare_revision_walk(struct rev_info *revs)
2639{
2640        int nr = revs->pending.nr;
2641        struct object_array_entry *e, *list;
2642        struct commit_list **next = &revs->commits;
2643
2644        e = list = revs->pending.objects;
2645        revs->pending.nr = 0;
2646        revs->pending.alloc = 0;
2647        revs->pending.objects = NULL;
2648        while (--nr >= 0) {
2649                struct commit *commit = handle_commit(revs, e->item, e->name);
2650                if (commit) {
2651                        if (!(commit->object.flags & SEEN)) {
2652                                commit->object.flags |= SEEN;
2653                                next = commit_list_append(commit, next);
2654                        }
2655                }
2656                e++;
2657        }
2658        if (!revs->leak_pending)
2659                free(list);
2660
2661        /* Signal whether we need per-parent treesame decoration */
2662        if (revs->simplify_merges ||
2663            (revs->limited && limiting_can_increase_treesame(revs)))
2664                revs->treesame.name = "treesame";
2665
2666        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
2667                commit_list_sort_by_date(&revs->commits);
2668        if (revs->no_walk)
2669                return 0;
2670        if (revs->limited)
2671                if (limit_list(revs) < 0)
2672                        return -1;
2673        if (revs->topo_order)
2674                sort_in_topological_order(&revs->commits, revs->sort_order);
2675        if (revs->line_level_traverse)
2676                line_log_filter(revs);
2677        if (revs->simplify_merges)
2678                simplify_merges(revs);
2679        if (revs->children.name)
2680                set_children(revs);
2681        return 0;
2682}
2683
2684static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
2685{
2686        struct commit_list *cache = NULL;
2687
2688        for (;;) {
2689                struct commit *p = *pp;
2690                if (!revs->limited)
2691                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
2692                                return rewrite_one_error;
2693                if (p->object.flags & UNINTERESTING)
2694                        return rewrite_one_ok;
2695                if (!(p->object.flags & TREESAME))
2696                        return rewrite_one_ok;
2697                if (!p->parents)
2698                        return rewrite_one_noparents;
2699                if ((p = one_relevant_parent(revs, p->parents)) == NULL)
2700                        return rewrite_one_ok;
2701                *pp = p;
2702        }
2703}
2704
2705int rewrite_parents(struct rev_info *revs, struct commit *commit,
2706        rewrite_parent_fn_t rewrite_parent)
2707{
2708        struct commit_list **pp = &commit->parents;
2709        while (*pp) {
2710                struct commit_list *parent = *pp;
2711                switch (rewrite_parent(revs, &parent->item)) {
2712                case rewrite_one_ok:
2713                        break;
2714                case rewrite_one_noparents:
2715                        *pp = parent->next;
2716                        continue;
2717                case rewrite_one_error:
2718                        return -1;
2719                }
2720                pp = &parent->next;
2721        }
2722        remove_duplicate_parents(revs, commit);
2723        return 0;
2724}
2725
2726static int commit_rewrite_person(struct strbuf *buf, const char *what, struct string_list *mailmap)
2727{
2728        char *person, *endp;
2729        size_t len, namelen, maillen;
2730        const char *name;
2731        const char *mail;
2732        struct ident_split ident;
2733
2734        person = strstr(buf->buf, what);
2735        if (!person)
2736                return 0;
2737
2738        person += strlen(what);
2739        endp = strchr(person, '\n');
2740        if (!endp)
2741                return 0;
2742
2743        len = endp - person;
2744
2745        if (split_ident_line(&ident, person, len))
2746                return 0;
2747
2748        mail = ident.mail_begin;
2749        maillen = ident.mail_end - ident.mail_begin;
2750        name = ident.name_begin;
2751        namelen = ident.name_end - ident.name_begin;
2752
2753        if (map_user(mailmap, &mail, &maillen, &name, &namelen)) {
2754                struct strbuf namemail = STRBUF_INIT;
2755
2756                strbuf_addf(&namemail, "%.*s <%.*s>",
2757                            (int)namelen, name, (int)maillen, mail);
2758
2759                strbuf_splice(buf, ident.name_begin - buf->buf,
2760                              ident.mail_end - ident.name_begin + 1,
2761                              namemail.buf, namemail.len);
2762
2763                strbuf_release(&namemail);
2764
2765                return 1;
2766        }
2767
2768        return 0;
2769}
2770
2771static int commit_match(struct commit *commit, struct rev_info *opt)
2772{
2773        int retval;
2774        const char *encoding;
2775        char *message;
2776        struct strbuf buf = STRBUF_INIT;
2777
2778        if (!opt->grep_filter.pattern_list && !opt->grep_filter.header_list)
2779                return 1;
2780
2781        /* Prepend "fake" headers as needed */
2782        if (opt->grep_filter.use_reflog_filter) {
2783                strbuf_addstr(&buf, "reflog ");
2784                get_reflog_message(&buf, opt->reflog_info);
2785                strbuf_addch(&buf, '\n');
2786        }
2787
2788        /*
2789         * We grep in the user's output encoding, under the assumption that it
2790         * is the encoding they are most likely to write their grep pattern
2791         * for. In addition, it means we will match the "notes" encoding below,
2792         * so we will not end up with a buffer that has two different encodings
2793         * in it.
2794         */
2795        encoding = get_log_output_encoding();
2796        message = logmsg_reencode(commit, NULL, encoding);
2797
2798        /* Copy the commit to temporary if we are using "fake" headers */
2799        if (buf.len)
2800                strbuf_addstr(&buf, message);
2801
2802        if (opt->grep_filter.header_list && opt->mailmap) {
2803                if (!buf.len)
2804                        strbuf_addstr(&buf, message);
2805
2806                commit_rewrite_person(&buf, "\nauthor ", opt->mailmap);
2807                commit_rewrite_person(&buf, "\ncommitter ", opt->mailmap);
2808        }
2809
2810        /* Append "fake" message parts as needed */
2811        if (opt->show_notes) {
2812                if (!buf.len)
2813                        strbuf_addstr(&buf, message);
2814                format_display_notes(commit->object.sha1, &buf, encoding, 1);
2815        }
2816
2817        /* Find either in the original commit message, or in the temporary */
2818        if (buf.len)
2819                retval = grep_buffer(&opt->grep_filter, buf.buf, buf.len);
2820        else
2821                retval = grep_buffer(&opt->grep_filter,
2822                                     message, strlen(message));
2823        strbuf_release(&buf);
2824        logmsg_free(message, commit);
2825        return retval;
2826}
2827
2828static inline int want_ancestry(const struct rev_info *revs)
2829{
2830        return (revs->rewrite_parents || revs->children.name);
2831}
2832
2833enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
2834{
2835        if (commit->object.flags & SHOWN)
2836                return commit_ignore;
2837        if (revs->unpacked && has_sha1_pack(commit->object.sha1))
2838                return commit_ignore;
2839        if (revs->show_all)
2840                return commit_show;
2841        if (commit->object.flags & UNINTERESTING)
2842                return commit_ignore;
2843        if (revs->min_age != -1 && (commit->date > revs->min_age))
2844                return commit_ignore;
2845        if (revs->min_parents || (revs->max_parents >= 0)) {
2846                int n = commit_list_count(commit->parents);
2847                if ((n < revs->min_parents) ||
2848                    ((revs->max_parents >= 0) && (n > revs->max_parents)))
2849                        return commit_ignore;
2850        }
2851        if (!commit_match(commit, revs))
2852                return commit_ignore;
2853        if (revs->prune && revs->dense) {
2854                /* Commit without changes? */
2855                if (commit->object.flags & TREESAME) {
2856                        int n;
2857                        struct commit_list *p;
2858                        /* drop merges unless we want parenthood */
2859                        if (!want_ancestry(revs))
2860                                return commit_ignore;
2861                        /*
2862                         * If we want ancestry, then need to keep any merges
2863                         * between relevant commits to tie together topology.
2864                         * For consistency with TREESAME and simplification
2865                         * use "relevant" here rather than just INTERESTING,
2866                         * to treat bottom commit(s) as part of the topology.
2867                         */
2868                        for (n = 0, p = commit->parents; p; p = p->next)
2869                                if (relevant_commit(p->item))
2870                                        if (++n >= 2)
2871                                                return commit_show;
2872                        return commit_ignore;
2873                }
2874        }
2875        return commit_show;
2876}
2877
2878enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
2879{
2880        enum commit_action action = get_commit_action(revs, commit);
2881
2882        if (action == commit_show &&
2883            !revs->show_all &&
2884            revs->prune && revs->dense && want_ancestry(revs)) {
2885                /*
2886                 * --full-diff on simplified parents is no good: it
2887                 * will show spurious changes from the commits that
2888                 * were elided.  So we save the parents on the side
2889                 * when --full-diff is in effect.
2890                 */
2891                if (revs->full_diff)
2892                        save_parents(revs, commit);
2893                if (rewrite_parents(revs, commit, rewrite_one) < 0)
2894                        return commit_error;
2895        }
2896        return action;
2897}
2898
2899static struct commit *get_revision_1(struct rev_info *revs)
2900{
2901        if (!revs->commits)
2902                return NULL;
2903
2904        do {
2905                struct commit_list *entry = revs->commits;
2906                struct commit *commit = entry->item;
2907
2908                revs->commits = entry->next;
2909                free(entry);
2910
2911                if (revs->reflog_info) {
2912                        save_parents(revs, commit);
2913                        fake_reflog_parent(revs->reflog_info, commit);
2914                        commit->object.flags &= ~(ADDED | SEEN | SHOWN);
2915                }
2916
2917                /*
2918                 * If we haven't done the list limiting, we need to look at
2919                 * the parents here. We also need to do the date-based limiting
2920                 * that we'd otherwise have done in limit_list().
2921                 */
2922                if (!revs->limited) {
2923                        if (revs->max_age != -1 &&
2924                            (commit->date < revs->max_age))
2925                                continue;
2926                        if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0)
2927                                die("Failed to traverse parents of commit %s",
2928                                    sha1_to_hex(commit->object.sha1));
2929                }
2930
2931                switch (simplify_commit(revs, commit)) {
2932                case commit_ignore:
2933                        continue;
2934                case commit_error:
2935                        die("Failed to simplify parents of commit %s",
2936                            sha1_to_hex(commit->object.sha1));
2937                default:
2938                        return commit;
2939                }
2940        } while (revs->commits);
2941        return NULL;
2942}
2943
2944/*
2945 * Return true for entries that have not yet been shown.  (This is an
2946 * object_array_each_func_t.)
2947 */
2948static int entry_unshown(struct object_array_entry *entry, void *cb_data_unused)
2949{
2950        return !(entry->item->flags & SHOWN);
2951}
2952
2953/*
2954 * If array is on the verge of a realloc, garbage-collect any entries
2955 * that have already been shown to try to free up some space.
2956 */
2957static void gc_boundary(struct object_array *array)
2958{
2959        if (array->nr == array->alloc)
2960                object_array_filter(array, entry_unshown, NULL);
2961}
2962
2963static void create_boundary_commit_list(struct rev_info *revs)
2964{
2965        unsigned i;
2966        struct commit *c;
2967        struct object_array *array = &revs->boundary_commits;
2968        struct object_array_entry *objects = array->objects;
2969
2970        /*
2971         * If revs->commits is non-NULL at this point, an error occurred in
2972         * get_revision_1().  Ignore the error and continue printing the
2973         * boundary commits anyway.  (This is what the code has always
2974         * done.)
2975         */
2976        if (revs->commits) {
2977                free_commit_list(revs->commits);
2978                revs->commits = NULL;
2979        }
2980
2981        /*
2982         * Put all of the actual boundary commits from revs->boundary_commits
2983         * into revs->commits
2984         */
2985        for (i = 0; i < array->nr; i++) {
2986                c = (struct commit *)(objects[i].item);
2987                if (!c)
2988                        continue;
2989                if (!(c->object.flags & CHILD_SHOWN))
2990                        continue;
2991                if (c->object.flags & (SHOWN | BOUNDARY))
2992                        continue;
2993                c->object.flags |= BOUNDARY;
2994                commit_list_insert(c, &revs->commits);
2995        }
2996
2997        /*
2998         * If revs->topo_order is set, sort the boundary commits
2999         * in topological order
3000         */
3001        sort_in_topological_order(&revs->commits, revs->sort_order);
3002}
3003
3004static struct commit *get_revision_internal(struct rev_info *revs)
3005{
3006        struct commit *c = NULL;
3007        struct commit_list *l;
3008
3009        if (revs->boundary == 2) {
3010                /*
3011                 * All of the normal commits have already been returned,
3012                 * and we are now returning boundary commits.
3013                 * create_boundary_commit_list() has populated
3014                 * revs->commits with the remaining commits to return.
3015                 */
3016                c = pop_commit(&revs->commits);
3017                if (c)
3018                        c->object.flags |= SHOWN;
3019                return c;
3020        }
3021
3022        /*
3023         * If our max_count counter has reached zero, then we are done. We
3024         * don't simply return NULL because we still might need to show
3025         * boundary commits. But we want to avoid calling get_revision_1, which
3026         * might do a considerable amount of work finding the next commit only
3027         * for us to throw it away.
3028         *
3029         * If it is non-zero, then either we don't have a max_count at all
3030         * (-1), or it is still counting, in which case we decrement.
3031         */
3032        if (revs->max_count) {
3033                c = get_revision_1(revs);
3034                if (c) {
3035                        while (revs->skip_count > 0) {
3036                                revs->skip_count--;
3037                                c = get_revision_1(revs);
3038                                if (!c)
3039                                        break;
3040                        }
3041                }
3042
3043                if (revs->max_count > 0)
3044                        revs->max_count--;
3045        }
3046
3047        if (c)
3048                c->object.flags |= SHOWN;
3049
3050        if (!revs->boundary)
3051                return c;
3052
3053        if (!c) {
3054                /*
3055                 * get_revision_1() runs out the commits, and
3056                 * we are done computing the boundaries.
3057                 * switch to boundary commits output mode.
3058                 */
3059                revs->boundary = 2;
3060
3061                /*
3062                 * Update revs->commits to contain the list of
3063                 * boundary commits.
3064                 */
3065                create_boundary_commit_list(revs);
3066
3067                return get_revision_internal(revs);
3068        }
3069
3070        /*
3071         * boundary commits are the commits that are parents of the
3072         * ones we got from get_revision_1() but they themselves are
3073         * not returned from get_revision_1().  Before returning
3074         * 'c', we need to mark its parents that they could be boundaries.
3075         */
3076
3077        for (l = c->parents; l; l = l->next) {
3078                struct object *p;
3079                p = &(l->item->object);
3080                if (p->flags & (CHILD_SHOWN | SHOWN))
3081                        continue;
3082                p->flags |= CHILD_SHOWN;
3083                gc_boundary(&revs->boundary_commits);
3084                add_object_array(p, NULL, &revs->boundary_commits);
3085        }
3086
3087        return c;
3088}
3089
3090struct commit *get_revision(struct rev_info *revs)
3091{
3092        struct commit *c;
3093        struct commit_list *reversed;
3094
3095        if (revs->reverse) {
3096                reversed = NULL;
3097                while ((c = get_revision_internal(revs)))
3098                        commit_list_insert(c, &reversed);
3099                revs->commits = reversed;
3100                revs->reverse = 0;
3101                revs->reverse_output_stage = 1;
3102        }
3103
3104        if (revs->reverse_output_stage)
3105                return pop_commit(&revs->commits);
3106
3107        c = get_revision_internal(revs);
3108        if (c && revs->graph)
3109                graph_update(revs->graph, c);
3110        if (!c)
3111                free_saved_parents(revs);
3112        return c;
3113}
3114
3115char *get_revision_mark(const struct rev_info *revs, const struct commit *commit)
3116{
3117        if (commit->object.flags & BOUNDARY)
3118                return "-";
3119        else if (commit->object.flags & UNINTERESTING)
3120                return "^";
3121        else if (commit->object.flags & PATCHSAME)
3122                return "=";
3123        else if (!revs || revs->left_right) {
3124                if (commit->object.flags & SYMMETRIC_LEFT)
3125                        return "<";
3126                else
3127                        return ">";
3128        } else if (revs->graph)
3129                return "*";
3130        else if (revs->cherry_mark)
3131                return "+";
3132        return "";
3133}
3134
3135void put_revision_mark(const struct rev_info *revs, const struct commit *commit)
3136{
3137        char *mark = get_revision_mark(revs, commit);
3138        if (!strlen(mark))
3139                return;
3140        fputs(mark, stdout);
3141        putchar(' ');
3142}
3143
3144define_commit_slab(saved_parents, struct commit_list *);
3145
3146#define EMPTY_PARENT_LIST ((struct commit_list *)-1)
3147
3148void save_parents(struct rev_info *revs, struct commit *commit)
3149{
3150        struct commit_list **pp;
3151
3152        if (!revs->saved_parents_slab) {
3153                revs->saved_parents_slab = xmalloc(sizeof(struct saved_parents));
3154                init_saved_parents(revs->saved_parents_slab);
3155        }
3156
3157        pp = saved_parents_at(revs->saved_parents_slab, commit);
3158
3159        /*
3160         * When walking with reflogs, we may visit the same commit
3161         * several times: once for each appearance in the reflog.
3162         *
3163         * In this case, save_parents() will be called multiple times.
3164         * We want to keep only the first set of parents.  We need to
3165         * store a sentinel value for an empty (i.e., NULL) parent
3166         * list to distinguish it from a not-yet-saved list, however.
3167         */
3168        if (*pp)
3169                return;
3170        if (commit->parents)
3171                *pp = copy_commit_list(commit->parents);
3172        else
3173                *pp = EMPTY_PARENT_LIST;
3174}
3175
3176struct commit_list *get_saved_parents(struct rev_info *revs, const struct commit *commit)
3177{
3178        struct commit_list *parents;
3179
3180        if (!revs->saved_parents_slab)
3181                return commit->parents;
3182
3183        parents = *saved_parents_at(revs->saved_parents_slab, commit);
3184        if (parents == EMPTY_PARENT_LIST)
3185                return NULL;
3186        return parents;
3187}
3188
3189void free_saved_parents(struct rev_info *revs)
3190{
3191        if (revs->saved_parents_slab)
3192                clear_saved_parents(revs->saved_parents_slab);
3193}