revision.con commit Merge branch 'maint-1.6.1' into maint-1.6.2 (c503467)
   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
  16volatile show_early_output_fn_t show_early_output;
  17
  18char *path_name(const struct name_path *path, const char *name)
  19{
  20        const struct name_path *p;
  21        char *n, *m;
  22        int nlen = strlen(name);
  23        int len = nlen + 1;
  24
  25        for (p = path; p; p = p->up) {
  26                if (p->elem_len)
  27                        len += p->elem_len + 1;
  28        }
  29        n = xmalloc(len);
  30        m = n + len - (nlen + 1);
  31        strcpy(m, name);
  32        for (p = path; p; p = p->up) {
  33                if (p->elem_len) {
  34                        m -= p->elem_len + 1;
  35                        memcpy(m, p->elem, p->elem_len);
  36                        m[p->elem_len] = '/';
  37                }
  38        }
  39        return n;
  40}
  41
  42void add_object(struct object *obj,
  43                struct object_array *p,
  44                struct name_path *path,
  45                const char *name)
  46{
  47        add_object_array(obj, path_name(path, name), p);
  48}
  49
  50static void mark_blob_uninteresting(struct blob *blob)
  51{
  52        if (!blob)
  53                return;
  54        if (blob->object.flags & UNINTERESTING)
  55                return;
  56        blob->object.flags |= UNINTERESTING;
  57}
  58
  59void mark_tree_uninteresting(struct tree *tree)
  60{
  61        struct tree_desc desc;
  62        struct name_entry entry;
  63        struct object *obj = &tree->object;
  64
  65        if (!tree)
  66                return;
  67        if (obj->flags & UNINTERESTING)
  68                return;
  69        obj->flags |= UNINTERESTING;
  70        if (!has_sha1_file(obj->sha1))
  71                return;
  72        if (parse_tree(tree) < 0)
  73                die("bad tree %s", sha1_to_hex(obj->sha1));
  74
  75        init_tree_desc(&desc, tree->buffer, tree->size);
  76        while (tree_entry(&desc, &entry)) {
  77                switch (object_type(entry.mode)) {
  78                case OBJ_TREE:
  79                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  80                        break;
  81                case OBJ_BLOB:
  82                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  83                        break;
  84                default:
  85                        /* Subproject commit - not in this repository */
  86                        break;
  87                }
  88        }
  89
  90        /*
  91         * We don't care about the tree any more
  92         * after it has been marked uninteresting.
  93         */
  94        free(tree->buffer);
  95        tree->buffer = NULL;
  96}
  97
  98void mark_parents_uninteresting(struct commit *commit)
  99{
 100        struct commit_list *parents = commit->parents;
 101
 102        while (parents) {
 103                struct commit *commit = parents->item;
 104                if (!(commit->object.flags & UNINTERESTING)) {
 105                        commit->object.flags |= UNINTERESTING;
 106
 107                        /*
 108                         * Normally we haven't parsed the parent
 109                         * yet, so we won't have a parent of a parent
 110                         * here. However, it may turn out that we've
 111                         * reached this commit some other way (where it
 112                         * wasn't uninteresting), in which case we need
 113                         * to mark its parents recursively too..
 114                         */
 115                        if (commit->parents)
 116                                mark_parents_uninteresting(commit);
 117                }
 118
 119                /*
 120                 * A missing commit is ok iff its parent is marked
 121                 * uninteresting.
 122                 *
 123                 * We just mark such a thing parsed, so that when
 124                 * it is popped next time around, we won't be trying
 125                 * to parse it and get an error.
 126                 */
 127                if (!has_sha1_file(commit->object.sha1))
 128                        commit->object.parsed = 1;
 129                parents = parents->next;
 130        }
 131}
 132
 133static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
 134{
 135        if (revs->no_walk && (obj->flags & UNINTERESTING))
 136                die("object ranges do not make sense when not walking revisions");
 137        if (revs->reflog_info && obj->type == OBJ_COMMIT &&
 138                        add_reflog_for_walk(revs->reflog_info,
 139                                (struct commit *)obj, name))
 140                return;
 141        add_object_array_with_mode(obj, name, &revs->pending, mode);
 142}
 143
 144void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 145{
 146        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 147}
 148
 149void add_head_to_pending(struct rev_info *revs)
 150{
 151        unsigned char sha1[20];
 152        struct object *obj;
 153        if (get_sha1("HEAD", sha1))
 154                return;
 155        obj = parse_object(sha1);
 156        if (!obj)
 157                return;
 158        add_pending_object(revs, obj, "HEAD");
 159}
 160
 161static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 162{
 163        struct object *object;
 164
 165        object = parse_object(sha1);
 166        if (!object)
 167                die("bad object %s", name);
 168        object->flags |= flags;
 169        return object;
 170}
 171
 172static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 173{
 174        unsigned long flags = object->flags;
 175
 176        /*
 177         * Tag object? Look what it points to..
 178         */
 179        while (object->type == OBJ_TAG) {
 180                struct tag *tag = (struct tag *) object;
 181                if (revs->tag_objects && !(flags & UNINTERESTING))
 182                        add_pending_object(revs, object, tag->tag);
 183                if (!tag->tagged)
 184                        die("bad tag");
 185                object = parse_object(tag->tagged->sha1);
 186                if (!object) {
 187                        if (flags & UNINTERESTING)
 188                                return NULL;
 189                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 190                }
 191        }
 192
 193        /*
 194         * Commit object? Just return it, we'll do all the complex
 195         * reachability crud.
 196         */
 197        if (object->type == OBJ_COMMIT) {
 198                struct commit *commit = (struct commit *)object;
 199                if (parse_commit(commit) < 0)
 200                        die("unable to parse commit %s", name);
 201                if (flags & UNINTERESTING) {
 202                        commit->object.flags |= UNINTERESTING;
 203                        mark_parents_uninteresting(commit);
 204                        revs->limited = 1;
 205                }
 206                if (revs->show_source && !commit->util)
 207                        commit->util = (void *) name;
 208                return commit;
 209        }
 210
 211        /*
 212         * Tree object? Either mark it uniniteresting, or add it
 213         * to the list of objects to look at later..
 214         */
 215        if (object->type == OBJ_TREE) {
 216                struct tree *tree = (struct tree *)object;
 217                if (!revs->tree_objects)
 218                        return NULL;
 219                if (flags & UNINTERESTING) {
 220                        mark_tree_uninteresting(tree);
 221                        return NULL;
 222                }
 223                add_pending_object(revs, object, "");
 224                return NULL;
 225        }
 226
 227        /*
 228         * Blob object? You know the drill by now..
 229         */
 230        if (object->type == OBJ_BLOB) {
 231                struct blob *blob = (struct blob *)object;
 232                if (!revs->blob_objects)
 233                        return NULL;
 234                if (flags & UNINTERESTING) {
 235                        mark_blob_uninteresting(blob);
 236                        return NULL;
 237                }
 238                add_pending_object(revs, object, "");
 239                return NULL;
 240        }
 241        die("%s is unknown object", name);
 242}
 243
 244static int everybody_uninteresting(struct commit_list *orig)
 245{
 246        struct commit_list *list = orig;
 247        while (list) {
 248                struct commit *commit = list->item;
 249                list = list->next;
 250                if (commit->object.flags & UNINTERESTING)
 251                        continue;
 252                return 0;
 253        }
 254        return 1;
 255}
 256
 257/*
 258 * The goal is to get REV_TREE_NEW as the result only if the
 259 * diff consists of all '+' (and no other changes), and
 260 * REV_TREE_DIFFERENT otherwise (of course if the trees are
 261 * the same we want REV_TREE_SAME).  That means that once we
 262 * get to REV_TREE_DIFFERENT, we do not have to look any further.
 263 */
 264static int tree_difference = REV_TREE_SAME;
 265
 266static void file_add_remove(struct diff_options *options,
 267                    int addremove, unsigned mode,
 268                    const unsigned char *sha1,
 269                    const char *fullpath)
 270{
 271        int diff = REV_TREE_DIFFERENT;
 272
 273        /*
 274         * Is it an add of a new file? It means that the old tree
 275         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 276         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 277         * (and if it already was "REV_TREE_NEW", we'll keep it
 278         * "REV_TREE_NEW" of course).
 279         */
 280        if (addremove == '+') {
 281                diff = tree_difference;
 282                if (diff != REV_TREE_SAME)
 283                        return;
 284                diff = REV_TREE_NEW;
 285        }
 286        tree_difference = diff;
 287        if (tree_difference == REV_TREE_DIFFERENT)
 288                DIFF_OPT_SET(options, HAS_CHANGES);
 289}
 290
 291static void file_change(struct diff_options *options,
 292                 unsigned old_mode, unsigned new_mode,
 293                 const unsigned char *old_sha1,
 294                 const unsigned char *new_sha1,
 295                 const char *fullpath)
 296{
 297        tree_difference = REV_TREE_DIFFERENT;
 298        DIFF_OPT_SET(options, HAS_CHANGES);
 299}
 300
 301static int rev_compare_tree(struct rev_info *revs, struct commit *parent, struct commit *commit)
 302{
 303        struct tree *t1 = parent->tree;
 304        struct tree *t2 = commit->tree;
 305
 306        if (!t1)
 307                return REV_TREE_NEW;
 308
 309        if (revs->simplify_by_decoration) {
 310                /*
 311                 * If we are simplifying by decoration, then the commit
 312                 * is worth showing if it has a tag pointing at it.
 313                 */
 314                if (lookup_decoration(&name_decoration, &commit->object))
 315                        return REV_TREE_DIFFERENT;
 316                /*
 317                 * A commit that is not pointed by a tag is uninteresting
 318                 * if we are not limited by path.  This means that you will
 319                 * see the usual "commits that touch the paths" plus any
 320                 * tagged commit by specifying both --simplify-by-decoration
 321                 * and pathspec.
 322                 */
 323                if (!revs->prune_data)
 324                        return REV_TREE_SAME;
 325        }
 326        if (!t2)
 327                return REV_TREE_DIFFERENT;
 328        tree_difference = REV_TREE_SAME;
 329        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 330        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 331                           &revs->pruning) < 0)
 332                return REV_TREE_DIFFERENT;
 333        return tree_difference;
 334}
 335
 336static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 337{
 338        int retval;
 339        void *tree;
 340        unsigned long size;
 341        struct tree_desc empty, real;
 342        struct tree *t1 = commit->tree;
 343
 344        if (!t1)
 345                return 0;
 346
 347        tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
 348        if (!tree)
 349                return 0;
 350        init_tree_desc(&real, tree, size);
 351        init_tree_desc(&empty, "", 0);
 352
 353        tree_difference = REV_TREE_SAME;
 354        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 355        retval = diff_tree(&empty, &real, "", &revs->pruning);
 356        free(tree);
 357
 358        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 359}
 360
 361static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 362{
 363        struct commit_list **pp, *parent;
 364        int tree_changed = 0, tree_same = 0;
 365
 366        /*
 367         * If we don't do pruning, everything is interesting
 368         */
 369        if (!revs->prune)
 370                return;
 371
 372        if (!commit->tree)
 373                return;
 374
 375        if (!commit->parents) {
 376                if (rev_same_tree_as_empty(revs, commit))
 377                        commit->object.flags |= TREESAME;
 378                return;
 379        }
 380
 381        /*
 382         * Normal non-merge commit? If we don't want to make the
 383         * history dense, we consider it always to be a change..
 384         */
 385        if (!revs->dense && !commit->parents->next)
 386                return;
 387
 388        pp = &commit->parents;
 389        while ((parent = *pp) != NULL) {
 390                struct commit *p = parent->item;
 391
 392                if (parse_commit(p) < 0)
 393                        die("cannot simplify commit %s (because of %s)",
 394                            sha1_to_hex(commit->object.sha1),
 395                            sha1_to_hex(p->object.sha1));
 396                switch (rev_compare_tree(revs, p, commit)) {
 397                case REV_TREE_SAME:
 398                        tree_same = 1;
 399                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 400                                /* Even if a merge with an uninteresting
 401                                 * side branch brought the entire change
 402                                 * we are interested in, we do not want
 403                                 * to lose the other branches of this
 404                                 * merge, so we just keep going.
 405                                 */
 406                                pp = &parent->next;
 407                                continue;
 408                        }
 409                        parent->next = NULL;
 410                        commit->parents = parent;
 411                        commit->object.flags |= TREESAME;
 412                        return;
 413
 414                case REV_TREE_NEW:
 415                        if (revs->remove_empty_trees &&
 416                            rev_same_tree_as_empty(revs, p)) {
 417                                /* We are adding all the specified
 418                                 * paths from this parent, so the
 419                                 * history beyond this parent is not
 420                                 * interesting.  Remove its parents
 421                                 * (they are grandparents for us).
 422                                 * IOW, we pretend this parent is a
 423                                 * "root" commit.
 424                                 */
 425                                if (parse_commit(p) < 0)
 426                                        die("cannot simplify commit %s (invalid %s)",
 427                                            sha1_to_hex(commit->object.sha1),
 428                                            sha1_to_hex(p->object.sha1));
 429                                p->parents = NULL;
 430                        }
 431                /* fallthrough */
 432                case REV_TREE_DIFFERENT:
 433                        tree_changed = 1;
 434                        pp = &parent->next;
 435                        continue;
 436                }
 437                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 438        }
 439        if (tree_changed && !tree_same)
 440                return;
 441        commit->object.flags |= TREESAME;
 442}
 443
 444static void insert_by_date_cached(struct commit *p, struct commit_list **head,
 445                    struct commit_list *cached_base, struct commit_list **cache)
 446{
 447        struct commit_list *new_entry;
 448
 449        if (cached_base && p->date < cached_base->item->date)
 450                new_entry = insert_by_date(p, &cached_base->next);
 451        else
 452                new_entry = insert_by_date(p, head);
 453
 454        if (cache && (!*cache || p->date < (*cache)->item->date))
 455                *cache = new_entry;
 456}
 457
 458static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 459                    struct commit_list **list, struct commit_list **cache_ptr)
 460{
 461        struct commit_list *parent = commit->parents;
 462        unsigned left_flag;
 463        struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 464
 465        if (commit->object.flags & ADDED)
 466                return 0;
 467        commit->object.flags |= ADDED;
 468
 469        /*
 470         * If the commit is uninteresting, don't try to
 471         * prune parents - we want the maximal uninteresting
 472         * set.
 473         *
 474         * Normally we haven't parsed the parent
 475         * yet, so we won't have a parent of a parent
 476         * here. However, it may turn out that we've
 477         * reached this commit some other way (where it
 478         * wasn't uninteresting), in which case we need
 479         * to mark its parents recursively too..
 480         */
 481        if (commit->object.flags & UNINTERESTING) {
 482                while (parent) {
 483                        struct commit *p = parent->item;
 484                        parent = parent->next;
 485                        if (p)
 486                                p->object.flags |= UNINTERESTING;
 487                        if (parse_commit(p) < 0)
 488                                continue;
 489                        if (p->parents)
 490                                mark_parents_uninteresting(p);
 491                        if (p->object.flags & SEEN)
 492                                continue;
 493                        p->object.flags |= SEEN;
 494                        insert_by_date_cached(p, list, cached_base, cache_ptr);
 495                }
 496                return 0;
 497        }
 498
 499        /*
 500         * Ok, the commit wasn't uninteresting. Try to
 501         * simplify the commit history and find the parent
 502         * that has no differences in the path set if one exists.
 503         */
 504        try_to_simplify_commit(revs, commit);
 505
 506        if (revs->no_walk)
 507                return 0;
 508
 509        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 510
 511        for (parent = commit->parents; parent; parent = parent->next) {
 512                struct commit *p = parent->item;
 513
 514                if (parse_commit(p) < 0)
 515                        return -1;
 516                if (revs->show_source && !p->util)
 517                        p->util = commit->util;
 518                p->object.flags |= left_flag;
 519                if (!(p->object.flags & SEEN)) {
 520                        p->object.flags |= SEEN;
 521                        insert_by_date_cached(p, list, cached_base, cache_ptr);
 522                }
 523                if (revs->first_parent_only)
 524                        break;
 525        }
 526        return 0;
 527}
 528
 529static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 530{
 531        struct commit_list *p;
 532        int left_count = 0, right_count = 0;
 533        int left_first;
 534        struct patch_ids ids;
 535
 536        /* First count the commits on the left and on the right */
 537        for (p = list; p; p = p->next) {
 538                struct commit *commit = p->item;
 539                unsigned flags = commit->object.flags;
 540                if (flags & BOUNDARY)
 541                        ;
 542                else if (flags & SYMMETRIC_LEFT)
 543                        left_count++;
 544                else
 545                        right_count++;
 546        }
 547
 548        left_first = left_count < right_count;
 549        init_patch_ids(&ids);
 550        if (revs->diffopt.nr_paths) {
 551                ids.diffopts.nr_paths = revs->diffopt.nr_paths;
 552                ids.diffopts.paths = revs->diffopt.paths;
 553                ids.diffopts.pathlens = revs->diffopt.pathlens;
 554        }
 555
 556        /* Compute patch-ids for one side */
 557        for (p = list; p; p = p->next) {
 558                struct commit *commit = p->item;
 559                unsigned flags = commit->object.flags;
 560
 561                if (flags & BOUNDARY)
 562                        continue;
 563                /*
 564                 * If we have fewer left, left_first is set and we omit
 565                 * commits on the right branch in this loop.  If we have
 566                 * fewer right, we skip the left ones.
 567                 */
 568                if (left_first != !!(flags & SYMMETRIC_LEFT))
 569                        continue;
 570                commit->util = add_commit_patch_id(commit, &ids);
 571        }
 572
 573        /* Check the other side */
 574        for (p = list; p; p = p->next) {
 575                struct commit *commit = p->item;
 576                struct patch_id *id;
 577                unsigned flags = commit->object.flags;
 578
 579                if (flags & BOUNDARY)
 580                        continue;
 581                /*
 582                 * If we have fewer left, left_first is set and we omit
 583                 * commits on the left branch in this loop.
 584                 */
 585                if (left_first == !!(flags & SYMMETRIC_LEFT))
 586                        continue;
 587
 588                /*
 589                 * Have we seen the same patch id?
 590                 */
 591                id = has_commit_patch_id(commit, &ids);
 592                if (!id)
 593                        continue;
 594                id->seen = 1;
 595                commit->object.flags |= SHOWN;
 596        }
 597
 598        /* Now check the original side for seen ones */
 599        for (p = list; p; p = p->next) {
 600                struct commit *commit = p->item;
 601                struct patch_id *ent;
 602
 603                ent = commit->util;
 604                if (!ent)
 605                        continue;
 606                if (ent->seen)
 607                        commit->object.flags |= SHOWN;
 608                commit->util = NULL;
 609        }
 610
 611        free_patch_ids(&ids);
 612}
 613
 614/* How many extra uninteresting commits we want to see.. */
 615#define SLOP 5
 616
 617static int still_interesting(struct commit_list *src, unsigned long date, int slop)
 618{
 619        /*
 620         * No source list at all? We're definitely done..
 621         */
 622        if (!src)
 623                return 0;
 624
 625        /*
 626         * Does the destination list contain entries with a date
 627         * before the source list? Definitely _not_ done.
 628         */
 629        if (date < src->item->date)
 630                return SLOP;
 631
 632        /*
 633         * Does the source list still have interesting commits in
 634         * it? Definitely not done..
 635         */
 636        if (!everybody_uninteresting(src))
 637                return SLOP;
 638
 639        /* Ok, we're closing in.. */
 640        return slop-1;
 641}
 642
 643static int limit_list(struct rev_info *revs)
 644{
 645        int slop = SLOP;
 646        unsigned long date = ~0ul;
 647        struct commit_list *list = revs->commits;
 648        struct commit_list *newlist = NULL;
 649        struct commit_list **p = &newlist;
 650
 651        while (list) {
 652                struct commit_list *entry = list;
 653                struct commit *commit = list->item;
 654                struct object *obj = &commit->object;
 655                show_early_output_fn_t show;
 656
 657                list = list->next;
 658                free(entry);
 659
 660                if (revs->max_age != -1 && (commit->date < revs->max_age))
 661                        obj->flags |= UNINTERESTING;
 662                if (add_parents_to_list(revs, commit, &list, NULL) < 0)
 663                        return -1;
 664                if (obj->flags & UNINTERESTING) {
 665                        mark_parents_uninteresting(commit);
 666                        if (revs->show_all)
 667                                p = &commit_list_insert(commit, p)->next;
 668                        slop = still_interesting(list, date, slop);
 669                        if (slop)
 670                                continue;
 671                        /* If showing all, add the whole pending list to the end */
 672                        if (revs->show_all)
 673                                *p = list;
 674                        break;
 675                }
 676                if (revs->min_age != -1 && (commit->date > revs->min_age))
 677                        continue;
 678                date = commit->date;
 679                p = &commit_list_insert(commit, p)->next;
 680
 681                show = show_early_output;
 682                if (!show)
 683                        continue;
 684
 685                show(revs, newlist);
 686                show_early_output = NULL;
 687        }
 688        if (revs->cherry_pick)
 689                cherry_pick_list(newlist, revs);
 690
 691        revs->commits = newlist;
 692        return 0;
 693}
 694
 695struct all_refs_cb {
 696        int all_flags;
 697        int warned_bad_reflog;
 698        struct rev_info *all_revs;
 699        const char *name_for_errormsg;
 700};
 701
 702static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 703{
 704        struct all_refs_cb *cb = cb_data;
 705        struct object *object = get_reference(cb->all_revs, path, sha1,
 706                                              cb->all_flags);
 707        add_pending_object(cb->all_revs, object, path);
 708        return 0;
 709}
 710
 711static void handle_refs(struct rev_info *revs, unsigned flags,
 712                int (*for_each)(each_ref_fn, void *))
 713{
 714        struct all_refs_cb cb;
 715        cb.all_revs = revs;
 716        cb.all_flags = flags;
 717        for_each(handle_one_ref, &cb);
 718}
 719
 720static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 721{
 722        struct all_refs_cb *cb = cb_data;
 723        if (!is_null_sha1(sha1)) {
 724                struct object *o = parse_object(sha1);
 725                if (o) {
 726                        o->flags |= cb->all_flags;
 727                        add_pending_object(cb->all_revs, o, "");
 728                }
 729                else if (!cb->warned_bad_reflog) {
 730                        warning("reflog of '%s' references pruned commits",
 731                                cb->name_for_errormsg);
 732                        cb->warned_bad_reflog = 1;
 733                }
 734        }
 735}
 736
 737static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 738                const char *email, unsigned long timestamp, int tz,
 739                const char *message, void *cb_data)
 740{
 741        handle_one_reflog_commit(osha1, cb_data);
 742        handle_one_reflog_commit(nsha1, cb_data);
 743        return 0;
 744}
 745
 746static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 747{
 748        struct all_refs_cb *cb = cb_data;
 749        cb->warned_bad_reflog = 0;
 750        cb->name_for_errormsg = path;
 751        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
 752        return 0;
 753}
 754
 755static void handle_reflog(struct rev_info *revs, unsigned flags)
 756{
 757        struct all_refs_cb cb;
 758        cb.all_revs = revs;
 759        cb.all_flags = flags;
 760        for_each_reflog(handle_one_reflog, &cb);
 761}
 762
 763static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 764{
 765        unsigned char sha1[20];
 766        struct object *it;
 767        struct commit *commit;
 768        struct commit_list *parents;
 769
 770        if (*arg == '^') {
 771                flags ^= UNINTERESTING;
 772                arg++;
 773        }
 774        if (get_sha1(arg, sha1))
 775                return 0;
 776        while (1) {
 777                it = get_reference(revs, arg, sha1, 0);
 778                if (it->type != OBJ_TAG)
 779                        break;
 780                if (!((struct tag*)it)->tagged)
 781                        return 0;
 782                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 783        }
 784        if (it->type != OBJ_COMMIT)
 785                return 0;
 786        commit = (struct commit *)it;
 787        for (parents = commit->parents; parents; parents = parents->next) {
 788                it = &parents->item->object;
 789                it->flags |= flags;
 790                add_pending_object(revs, it, arg);
 791        }
 792        return 1;
 793}
 794
 795void init_revisions(struct rev_info *revs, const char *prefix)
 796{
 797        memset(revs, 0, sizeof(*revs));
 798
 799        revs->abbrev = DEFAULT_ABBREV;
 800        revs->ignore_merges = 1;
 801        revs->simplify_history = 1;
 802        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
 803        DIFF_OPT_SET(&revs->pruning, QUIET);
 804        revs->pruning.add_remove = file_add_remove;
 805        revs->pruning.change = file_change;
 806        revs->lifo = 1;
 807        revs->dense = 1;
 808        revs->prefix = prefix;
 809        revs->max_age = -1;
 810        revs->min_age = -1;
 811        revs->skip_count = -1;
 812        revs->max_count = -1;
 813
 814        revs->commit_format = CMIT_FMT_DEFAULT;
 815
 816        revs->grep_filter.status_only = 1;
 817        revs->grep_filter.pattern_tail = &(revs->grep_filter.pattern_list);
 818        revs->grep_filter.regflags = REG_NEWLINE;
 819
 820        diff_setup(&revs->diffopt);
 821        if (prefix && !revs->diffopt.prefix) {
 822                revs->diffopt.prefix = prefix;
 823                revs->diffopt.prefix_length = strlen(prefix);
 824        }
 825}
 826
 827static void add_pending_commit_list(struct rev_info *revs,
 828                                    struct commit_list *commit_list,
 829                                    unsigned int flags)
 830{
 831        while (commit_list) {
 832                struct object *object = &commit_list->item->object;
 833                object->flags |= flags;
 834                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 835                commit_list = commit_list->next;
 836        }
 837}
 838
 839static void prepare_show_merge(struct rev_info *revs)
 840{
 841        struct commit_list *bases;
 842        struct commit *head, *other;
 843        unsigned char sha1[20];
 844        const char **prune = NULL;
 845        int i, prune_num = 1; /* counting terminating NULL */
 846
 847        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 848                die("--merge without HEAD?");
 849        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 850                die("--merge without MERGE_HEAD?");
 851        add_pending_object(revs, &head->object, "HEAD");
 852        add_pending_object(revs, &other->object, "MERGE_HEAD");
 853        bases = get_merge_bases(head, other, 1);
 854        add_pending_commit_list(revs, bases, UNINTERESTING);
 855        free_commit_list(bases);
 856        head->object.flags |= SYMMETRIC_LEFT;
 857
 858        if (!active_nr)
 859                read_cache();
 860        for (i = 0; i < active_nr; i++) {
 861                struct cache_entry *ce = active_cache[i];
 862                if (!ce_stage(ce))
 863                        continue;
 864                if (ce_path_match(ce, revs->prune_data)) {
 865                        prune_num++;
 866                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
 867                        prune[prune_num-2] = ce->name;
 868                        prune[prune_num-1] = NULL;
 869                }
 870                while ((i+1 < active_nr) &&
 871                       ce_same_name(ce, active_cache[i+1]))
 872                        i++;
 873        }
 874        revs->prune_data = prune;
 875        revs->limited = 1;
 876}
 877
 878int handle_revision_arg(const char *arg, struct rev_info *revs,
 879                        int flags,
 880                        int cant_be_filename)
 881{
 882        unsigned mode;
 883        char *dotdot;
 884        struct object *object;
 885        unsigned char sha1[20];
 886        int local_flags;
 887
 888        dotdot = strstr(arg, "..");
 889        if (dotdot) {
 890                unsigned char from_sha1[20];
 891                const char *next = dotdot + 2;
 892                const char *this = arg;
 893                int symmetric = *next == '.';
 894                unsigned int flags_exclude = flags ^ UNINTERESTING;
 895
 896                *dotdot = 0;
 897                next += symmetric;
 898
 899                if (!*next)
 900                        next = "HEAD";
 901                if (dotdot == arg)
 902                        this = "HEAD";
 903                if (!get_sha1(this, from_sha1) &&
 904                    !get_sha1(next, sha1)) {
 905                        struct commit *a, *b;
 906                        struct commit_list *exclude;
 907
 908                        a = lookup_commit_reference(from_sha1);
 909                        b = lookup_commit_reference(sha1);
 910                        if (!a || !b) {
 911                                die(symmetric ?
 912                                    "Invalid symmetric difference expression %s...%s" :
 913                                    "Invalid revision range %s..%s",
 914                                    arg, next);
 915                        }
 916
 917                        if (!cant_be_filename) {
 918                                *dotdot = '.';
 919                                verify_non_filename(revs->prefix, arg);
 920                        }
 921
 922                        if (symmetric) {
 923                                exclude = get_merge_bases(a, b, 1);
 924                                add_pending_commit_list(revs, exclude,
 925                                                        flags_exclude);
 926                                free_commit_list(exclude);
 927                                a->object.flags |= flags | SYMMETRIC_LEFT;
 928                        } else
 929                                a->object.flags |= flags_exclude;
 930                        b->object.flags |= flags;
 931                        add_pending_object(revs, &a->object, this);
 932                        add_pending_object(revs, &b->object, next);
 933                        return 0;
 934                }
 935                *dotdot = '.';
 936        }
 937        dotdot = strstr(arg, "^@");
 938        if (dotdot && !dotdot[2]) {
 939                *dotdot = 0;
 940                if (add_parents_only(revs, arg, flags))
 941                        return 0;
 942                *dotdot = '^';
 943        }
 944        dotdot = strstr(arg, "^!");
 945        if (dotdot && !dotdot[2]) {
 946                *dotdot = 0;
 947                if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
 948                        *dotdot = '^';
 949        }
 950
 951        local_flags = 0;
 952        if (*arg == '^') {
 953                local_flags = UNINTERESTING;
 954                arg++;
 955        }
 956        if (get_sha1_with_mode(arg, sha1, &mode))
 957                return -1;
 958        if (!cant_be_filename)
 959                verify_non_filename(revs->prefix, arg);
 960        object = get_reference(revs, arg, sha1, flags ^ local_flags);
 961        add_pending_object_with_mode(revs, object, arg, mode);
 962        return 0;
 963}
 964
 965void read_revisions_from_stdin(struct rev_info *revs)
 966{
 967        char line[1000];
 968
 969        while (fgets(line, sizeof(line), stdin) != NULL) {
 970                int len = strlen(line);
 971                if (len && line[len - 1] == '\n')
 972                        line[--len] = '\0';
 973                if (!len)
 974                        break;
 975                if (line[0] == '-')
 976                        die("options not supported in --stdin mode");
 977                if (handle_revision_arg(line, revs, 0, 1))
 978                        die("bad revision '%s'", line);
 979        }
 980}
 981
 982static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 983{
 984        append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
 985}
 986
 987static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
 988{
 989        append_header_grep_pattern(&revs->grep_filter, field, pattern);
 990}
 991
 992static void add_message_grep(struct rev_info *revs, const char *pattern)
 993{
 994        add_grep(revs, pattern, GREP_PATTERN_BODY);
 995}
 996
 997static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
 998                               int *unkc, const char **unkv)
 999{
1000        const char *arg = argv[0];
1001
1002        /* pseudo revision arguments */
1003        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
1004            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
1005            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
1006            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk"))
1007        {
1008                unkv[(*unkc)++] = arg;
1009                return 1;
1010        }
1011
1012        if (!prefixcmp(arg, "--max-count=")) {
1013                revs->max_count = atoi(arg + 12);
1014        } else if (!prefixcmp(arg, "--skip=")) {
1015                revs->skip_count = atoi(arg + 7);
1016        } else if ((*arg == '-') && isdigit(arg[1])) {
1017        /* accept -<digit>, like traditional "head" */
1018                revs->max_count = atoi(arg + 1);
1019        } else if (!strcmp(arg, "-n")) {
1020                if (argc <= 1)
1021                        return error("-n requires an argument");
1022                revs->max_count = atoi(argv[1]);
1023                return 2;
1024        } else if (!prefixcmp(arg, "-n")) {
1025                revs->max_count = atoi(arg + 2);
1026        } else if (!prefixcmp(arg, "--max-age=")) {
1027                revs->max_age = atoi(arg + 10);
1028        } else if (!prefixcmp(arg, "--since=")) {
1029                revs->max_age = approxidate(arg + 8);
1030        } else if (!prefixcmp(arg, "--after=")) {
1031                revs->max_age = approxidate(arg + 8);
1032        } else if (!prefixcmp(arg, "--min-age=")) {
1033                revs->min_age = atoi(arg + 10);
1034        } else if (!prefixcmp(arg, "--before=")) {
1035                revs->min_age = approxidate(arg + 9);
1036        } else if (!prefixcmp(arg, "--until=")) {
1037                revs->min_age = approxidate(arg + 8);
1038        } else if (!strcmp(arg, "--first-parent")) {
1039                revs->first_parent_only = 1;
1040        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1041                init_reflog_walk(&revs->reflog_info);
1042        } else if (!strcmp(arg, "--default")) {
1043                if (argc <= 1)
1044                        return error("bad --default argument");
1045                revs->def = argv[1];
1046                return 2;
1047        } else if (!strcmp(arg, "--merge")) {
1048                revs->show_merge = 1;
1049        } else if (!strcmp(arg, "--topo-order")) {
1050                revs->lifo = 1;
1051                revs->topo_order = 1;
1052        } else if (!strcmp(arg, "--simplify-merges")) {
1053                revs->simplify_merges = 1;
1054                revs->rewrite_parents = 1;
1055                revs->simplify_history = 0;
1056                revs->limited = 1;
1057        } else if (!strcmp(arg, "--simplify-by-decoration")) {
1058                revs->simplify_merges = 1;
1059                revs->rewrite_parents = 1;
1060                revs->simplify_history = 0;
1061                revs->simplify_by_decoration = 1;
1062                revs->limited = 1;
1063                revs->prune = 1;
1064                load_ref_decorations();
1065        } else if (!strcmp(arg, "--date-order")) {
1066                revs->lifo = 0;
1067                revs->topo_order = 1;
1068        } else if (!prefixcmp(arg, "--early-output")) {
1069                int count = 100;
1070                switch (arg[14]) {
1071                case '=':
1072                        count = atoi(arg+15);
1073                        /* Fallthrough */
1074                case 0:
1075                        revs->topo_order = 1;
1076                       revs->early_output = count;
1077                }
1078        } else if (!strcmp(arg, "--parents")) {
1079                revs->rewrite_parents = 1;
1080                revs->print_parents = 1;
1081        } else if (!strcmp(arg, "--dense")) {
1082                revs->dense = 1;
1083        } else if (!strcmp(arg, "--sparse")) {
1084                revs->dense = 0;
1085        } else if (!strcmp(arg, "--show-all")) {
1086                revs->show_all = 1;
1087        } else if (!strcmp(arg, "--remove-empty")) {
1088                revs->remove_empty_trees = 1;
1089        } else if (!strcmp(arg, "--no-merges")) {
1090                revs->no_merges = 1;
1091        } else if (!strcmp(arg, "--boundary")) {
1092                revs->boundary = 1;
1093        } else if (!strcmp(arg, "--left-right")) {
1094                revs->left_right = 1;
1095        } else if (!strcmp(arg, "--cherry-pick")) {
1096                revs->cherry_pick = 1;
1097                revs->limited = 1;
1098        } else if (!strcmp(arg, "--objects")) {
1099                revs->tag_objects = 1;
1100                revs->tree_objects = 1;
1101                revs->blob_objects = 1;
1102        } else if (!strcmp(arg, "--objects-edge")) {
1103                revs->tag_objects = 1;
1104                revs->tree_objects = 1;
1105                revs->blob_objects = 1;
1106                revs->edge_hint = 1;
1107        } else if (!strcmp(arg, "--unpacked")) {
1108                revs->unpacked = 1;
1109        } else if (!prefixcmp(arg, "--unpacked=")) {
1110                die("--unpacked=<packfile> no longer supported.");
1111        } else if (!strcmp(arg, "-r")) {
1112                revs->diff = 1;
1113                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1114        } else if (!strcmp(arg, "-t")) {
1115                revs->diff = 1;
1116                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1117                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1118        } else if (!strcmp(arg, "-m")) {
1119                revs->ignore_merges = 0;
1120        } else if (!strcmp(arg, "-c")) {
1121                revs->diff = 1;
1122                revs->dense_combined_merges = 0;
1123                revs->combine_merges = 1;
1124        } else if (!strcmp(arg, "--cc")) {
1125                revs->diff = 1;
1126                revs->dense_combined_merges = 1;
1127                revs->combine_merges = 1;
1128        } else if (!strcmp(arg, "-v")) {
1129                revs->verbose_header = 1;
1130        } else if (!strcmp(arg, "--pretty")) {
1131                revs->verbose_header = 1;
1132                get_commit_format(arg+8, revs);
1133        } else if (!prefixcmp(arg, "--pretty=")) {
1134                revs->verbose_header = 1;
1135                get_commit_format(arg+9, revs);
1136        } else if (!strcmp(arg, "--graph")) {
1137                revs->topo_order = 1;
1138                revs->rewrite_parents = 1;
1139                revs->graph = graph_init(revs);
1140        } else if (!strcmp(arg, "--root")) {
1141                revs->show_root_diff = 1;
1142        } else if (!strcmp(arg, "--no-commit-id")) {
1143                revs->no_commit_id = 1;
1144        } else if (!strcmp(arg, "--always")) {
1145                revs->always_show_header = 1;
1146        } else if (!strcmp(arg, "--no-abbrev")) {
1147                revs->abbrev = 0;
1148        } else if (!strcmp(arg, "--abbrev")) {
1149                revs->abbrev = DEFAULT_ABBREV;
1150        } else if (!prefixcmp(arg, "--abbrev=")) {
1151                revs->abbrev = strtoul(arg + 9, NULL, 10);
1152                if (revs->abbrev < MINIMUM_ABBREV)
1153                        revs->abbrev = MINIMUM_ABBREV;
1154                else if (revs->abbrev > 40)
1155                        revs->abbrev = 40;
1156        } else if (!strcmp(arg, "--abbrev-commit")) {
1157                revs->abbrev_commit = 1;
1158        } else if (!strcmp(arg, "--full-diff")) {
1159                revs->diff = 1;
1160                revs->full_diff = 1;
1161        } else if (!strcmp(arg, "--full-history")) {
1162                revs->simplify_history = 0;
1163        } else if (!strcmp(arg, "--relative-date")) {
1164                revs->date_mode = DATE_RELATIVE;
1165        } else if (!strncmp(arg, "--date=", 7)) {
1166                revs->date_mode = parse_date_format(arg + 7);
1167        } else if (!strcmp(arg, "--log-size")) {
1168                revs->show_log_size = 1;
1169        }
1170        /*
1171         * Grepping the commit log
1172         */
1173        else if (!prefixcmp(arg, "--author=")) {
1174                add_header_grep(revs, GREP_HEADER_AUTHOR, arg+9);
1175        } else if (!prefixcmp(arg, "--committer=")) {
1176                add_header_grep(revs, GREP_HEADER_COMMITTER, arg+12);
1177        } else if (!prefixcmp(arg, "--grep=")) {
1178                add_message_grep(revs, arg+7);
1179        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
1180                revs->grep_filter.regflags |= REG_EXTENDED;
1181        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
1182                revs->grep_filter.regflags |= REG_ICASE;
1183        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
1184                revs->grep_filter.fixed = 1;
1185        } else if (!strcmp(arg, "--all-match")) {
1186                revs->grep_filter.all_match = 1;
1187        } else if (!prefixcmp(arg, "--encoding=")) {
1188                arg += 11;
1189                if (strcmp(arg, "none"))
1190                        git_log_output_encoding = xstrdup(arg);
1191                else
1192                        git_log_output_encoding = "";
1193        } else if (!strcmp(arg, "--reverse")) {
1194                revs->reverse ^= 1;
1195        } else if (!strcmp(arg, "--children")) {
1196                revs->children.name = "children";
1197                revs->limited = 1;
1198        } else {
1199                int opts = diff_opt_parse(&revs->diffopt, argv, argc);
1200                if (!opts)
1201                        unkv[(*unkc)++] = arg;
1202                return opts;
1203        }
1204
1205        return 1;
1206}
1207
1208void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
1209                        const struct option *options,
1210                        const char * const usagestr[])
1211{
1212        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
1213                                    &ctx->cpidx, ctx->out);
1214        if (n <= 0) {
1215                error("unknown option `%s'", ctx->argv[0]);
1216                usage_with_options(usagestr, options);
1217        }
1218        ctx->argv += n;
1219        ctx->argc -= n;
1220}
1221
1222/*
1223 * Parse revision information, filling in the "rev_info" structure,
1224 * and removing the used arguments from the argument list.
1225 *
1226 * Returns the number of arguments left that weren't recognized
1227 * (which are also moved to the head of the argument list)
1228 */
1229int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
1230{
1231        int i, flags, left, seen_dashdash;
1232
1233        /* First, search for "--" */
1234        seen_dashdash = 0;
1235        for (i = 1; i < argc; i++) {
1236                const char *arg = argv[i];
1237                if (strcmp(arg, "--"))
1238                        continue;
1239                argv[i] = NULL;
1240                argc = i;
1241                if (argv[i + 1])
1242                        revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
1243                seen_dashdash = 1;
1244                break;
1245        }
1246
1247        /* Second, deal with arguments and options */
1248        flags = 0;
1249        for (left = i = 1; i < argc; i++) {
1250                const char *arg = argv[i];
1251                if (*arg == '-') {
1252                        int opts;
1253
1254                        if (!strcmp(arg, "--all")) {
1255                                handle_refs(revs, flags, for_each_ref);
1256                                handle_refs(revs, flags, head_ref);
1257                                continue;
1258                        }
1259                        if (!strcmp(arg, "--branches")) {
1260                                handle_refs(revs, flags, for_each_branch_ref);
1261                                continue;
1262                        }
1263                        if (!strcmp(arg, "--tags")) {
1264                                handle_refs(revs, flags, for_each_tag_ref);
1265                                continue;
1266                        }
1267                        if (!strcmp(arg, "--remotes")) {
1268                                handle_refs(revs, flags, for_each_remote_ref);
1269                                continue;
1270                        }
1271                        if (!strcmp(arg, "--reflog")) {
1272                                handle_reflog(revs, flags);
1273                                continue;
1274                        }
1275                        if (!strcmp(arg, "--not")) {
1276                                flags ^= UNINTERESTING;
1277                                continue;
1278                        }
1279                        if (!strcmp(arg, "--no-walk")) {
1280                                revs->no_walk = 1;
1281                                continue;
1282                        }
1283                        if (!strcmp(arg, "--do-walk")) {
1284                                revs->no_walk = 0;
1285                                continue;
1286                        }
1287
1288                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
1289                        if (opts > 0) {
1290                                i += opts - 1;
1291                                continue;
1292                        }
1293                        if (opts < 0)
1294                                exit(128);
1295                        continue;
1296                }
1297
1298                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1299                        int j;
1300                        if (seen_dashdash || *arg == '^')
1301                                die("bad revision '%s'", arg);
1302
1303                        /* If we didn't have a "--":
1304                         * (1) all filenames must exist;
1305                         * (2) all rev-args must not be interpretable
1306                         *     as a valid filename.
1307                         * but the latter we have checked in the main loop.
1308                         */
1309                        for (j = i; j < argc; j++)
1310                                verify_filename(revs->prefix, argv[j]);
1311
1312                        revs->prune_data = get_pathspec(revs->prefix,
1313                                                        argv + i);
1314                        break;
1315                }
1316        }
1317
1318        if (revs->def == NULL)
1319                revs->def = def;
1320        if (revs->show_merge)
1321                prepare_show_merge(revs);
1322        if (revs->def && !revs->pending.nr) {
1323                unsigned char sha1[20];
1324                struct object *object;
1325                unsigned mode;
1326                if (get_sha1_with_mode(revs->def, sha1, &mode))
1327                        die("bad default revision '%s'", revs->def);
1328                object = get_reference(revs, revs->def, sha1, 0);
1329                add_pending_object_with_mode(revs, object, revs->def, mode);
1330        }
1331
1332        /* Did the user ask for any diff output? Run the diff! */
1333        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
1334                revs->diff = 1;
1335
1336        /* Pickaxe, diff-filter and rename following need diffs */
1337        if (revs->diffopt.pickaxe ||
1338            revs->diffopt.filter ||
1339            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
1340                revs->diff = 1;
1341
1342        if (revs->topo_order)
1343                revs->limited = 1;
1344
1345        if (revs->prune_data) {
1346                diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1347                /* Can't prune commits with rename following: the paths change.. */
1348                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
1349                        revs->prune = 1;
1350                if (!revs->full_diff)
1351                        diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1352        }
1353        if (revs->combine_merges) {
1354                revs->ignore_merges = 0;
1355                if (revs->dense_combined_merges && !revs->diffopt.output_format)
1356                        revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1357        }
1358        revs->diffopt.abbrev = revs->abbrev;
1359        if (diff_setup_done(&revs->diffopt) < 0)
1360                die("diff_setup_done failed");
1361
1362        compile_grep_patterns(&revs->grep_filter);
1363
1364        if (revs->reverse && revs->reflog_info)
1365                die("cannot combine --reverse with --walk-reflogs");
1366        if (revs->rewrite_parents && revs->children.name)
1367                die("cannot combine --parents and --children");
1368
1369        /*
1370         * Limitations on the graph functionality
1371         */
1372        if (revs->reverse && revs->graph)
1373                die("cannot combine --reverse with --graph");
1374
1375        if (revs->reflog_info && revs->graph)
1376                die("cannot combine --walk-reflogs with --graph");
1377
1378        return left;
1379}
1380
1381static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
1382{
1383        struct commit_list *l = xcalloc(1, sizeof(*l));
1384
1385        l->item = child;
1386        l->next = add_decoration(&revs->children, &parent->object, l);
1387}
1388
1389static int remove_duplicate_parents(struct commit *commit)
1390{
1391        struct commit_list **pp, *p;
1392        int surviving_parents;
1393
1394        /* Examine existing parents while marking ones we have seen... */
1395        pp = &commit->parents;
1396        while ((p = *pp) != NULL) {
1397                struct commit *parent = p->item;
1398                if (parent->object.flags & TMP_MARK) {
1399                        *pp = p->next;
1400                        continue;
1401                }
1402                parent->object.flags |= TMP_MARK;
1403                pp = &p->next;
1404        }
1405        /* count them while clearing the temporary mark */
1406        surviving_parents = 0;
1407        for (p = commit->parents; p; p = p->next) {
1408                p->item->object.flags &= ~TMP_MARK;
1409                surviving_parents++;
1410        }
1411        return surviving_parents;
1412}
1413
1414struct merge_simplify_state {
1415        struct commit *simplified;
1416};
1417
1418static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
1419{
1420        struct merge_simplify_state *st;
1421
1422        st = lookup_decoration(&revs->merge_simplification, &commit->object);
1423        if (!st) {
1424                st = xcalloc(1, sizeof(*st));
1425                add_decoration(&revs->merge_simplification, &commit->object, st);
1426        }
1427        return st;
1428}
1429
1430static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
1431{
1432        struct commit_list *p;
1433        struct merge_simplify_state *st, *pst;
1434        int cnt;
1435
1436        st = locate_simplify_state(revs, commit);
1437
1438        /*
1439         * Have we handled this one?
1440         */
1441        if (st->simplified)
1442                return tail;
1443
1444        /*
1445         * An UNINTERESTING commit simplifies to itself, so does a
1446         * root commit.  We do not rewrite parents of such commit
1447         * anyway.
1448         */
1449        if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
1450                st->simplified = commit;
1451                return tail;
1452        }
1453
1454        /*
1455         * Do we know what commit all of our parents should be rewritten to?
1456         * Otherwise we are not ready to rewrite this one yet.
1457         */
1458        for (cnt = 0, p = commit->parents; p; p = p->next) {
1459                pst = locate_simplify_state(revs, p->item);
1460                if (!pst->simplified) {
1461                        tail = &commit_list_insert(p->item, tail)->next;
1462                        cnt++;
1463                }
1464        }
1465        if (cnt) {
1466                tail = &commit_list_insert(commit, tail)->next;
1467                return tail;
1468        }
1469
1470        /*
1471         * Rewrite our list of parents.
1472         */
1473        for (p = commit->parents; p; p = p->next) {
1474                pst = locate_simplify_state(revs, p->item);
1475                p->item = pst->simplified;
1476        }
1477        cnt = remove_duplicate_parents(commit);
1478
1479        /*
1480         * It is possible that we are a merge and one side branch
1481         * does not have any commit that touches the given paths;
1482         * in such a case, the immediate parents will be rewritten
1483         * to different commits.
1484         *
1485         *      o----X          X: the commit we are looking at;
1486         *     /    /           o: a commit that touches the paths;
1487         * ---o----'
1488         *
1489         * Further reduce the parents by removing redundant parents.
1490         */
1491        if (1 < cnt) {
1492                struct commit_list *h = reduce_heads(commit->parents);
1493                cnt = commit_list_count(h);
1494                free_commit_list(commit->parents);
1495                commit->parents = h;
1496        }
1497
1498        /*
1499         * A commit simplifies to itself if it is a root, if it is
1500         * UNINTERESTING, if it touches the given paths, or if it is a
1501         * merge and its parents simplifies to more than one commits
1502         * (the first two cases are already handled at the beginning of
1503         * this function).
1504         *
1505         * Otherwise, it simplifies to what its sole parent simplifies to.
1506         */
1507        if (!cnt ||
1508            (commit->object.flags & UNINTERESTING) ||
1509            !(commit->object.flags & TREESAME) ||
1510            (1 < cnt))
1511                st->simplified = commit;
1512        else {
1513                pst = locate_simplify_state(revs, commit->parents->item);
1514                st->simplified = pst->simplified;
1515        }
1516        return tail;
1517}
1518
1519static void simplify_merges(struct rev_info *revs)
1520{
1521        struct commit_list *list;
1522        struct commit_list *yet_to_do, **tail;
1523
1524        if (!revs->topo_order)
1525                sort_in_topological_order(&revs->commits, revs->lifo);
1526        if (!revs->prune)
1527                return;
1528
1529        /* feed the list reversed */
1530        yet_to_do = NULL;
1531        for (list = revs->commits; list; list = list->next)
1532                commit_list_insert(list->item, &yet_to_do);
1533        while (yet_to_do) {
1534                list = yet_to_do;
1535                yet_to_do = NULL;
1536                tail = &yet_to_do;
1537                while (list) {
1538                        struct commit *commit = list->item;
1539                        struct commit_list *next = list->next;
1540                        free(list);
1541                        list = next;
1542                        tail = simplify_one(revs, commit, tail);
1543                }
1544        }
1545
1546        /* clean up the result, removing the simplified ones */
1547        list = revs->commits;
1548        revs->commits = NULL;
1549        tail = &revs->commits;
1550        while (list) {
1551                struct commit *commit = list->item;
1552                struct commit_list *next = list->next;
1553                struct merge_simplify_state *st;
1554                free(list);
1555                list = next;
1556                st = locate_simplify_state(revs, commit);
1557                if (st->simplified == commit)
1558                        tail = &commit_list_insert(commit, tail)->next;
1559        }
1560}
1561
1562static void set_children(struct rev_info *revs)
1563{
1564        struct commit_list *l;
1565        for (l = revs->commits; l; l = l->next) {
1566                struct commit *commit = l->item;
1567                struct commit_list *p;
1568
1569                for (p = commit->parents; p; p = p->next)
1570                        add_child(revs, p->item, commit);
1571        }
1572}
1573
1574int prepare_revision_walk(struct rev_info *revs)
1575{
1576        int nr = revs->pending.nr;
1577        struct object_array_entry *e, *list;
1578
1579        e = list = revs->pending.objects;
1580        revs->pending.nr = 0;
1581        revs->pending.alloc = 0;
1582        revs->pending.objects = NULL;
1583        while (--nr >= 0) {
1584                struct commit *commit = handle_commit(revs, e->item, e->name);
1585                if (commit) {
1586                        if (!(commit->object.flags & SEEN)) {
1587                                commit->object.flags |= SEEN;
1588                                insert_by_date(commit, &revs->commits);
1589                        }
1590                }
1591                e++;
1592        }
1593        free(list);
1594
1595        if (revs->no_walk)
1596                return 0;
1597        if (revs->limited)
1598                if (limit_list(revs) < 0)
1599                        return -1;
1600        if (revs->topo_order)
1601                sort_in_topological_order(&revs->commits, revs->lifo);
1602        if (revs->simplify_merges)
1603                simplify_merges(revs);
1604        if (revs->children.name)
1605                set_children(revs);
1606        return 0;
1607}
1608
1609enum rewrite_result {
1610        rewrite_one_ok,
1611        rewrite_one_noparents,
1612        rewrite_one_error,
1613};
1614
1615static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
1616{
1617        struct commit_list *cache = NULL;
1618
1619        for (;;) {
1620                struct commit *p = *pp;
1621                if (!revs->limited)
1622                        if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
1623                                return rewrite_one_error;
1624                if (p->parents && p->parents->next)
1625                        return rewrite_one_ok;
1626                if (p->object.flags & UNINTERESTING)
1627                        return rewrite_one_ok;
1628                if (!(p->object.flags & TREESAME))
1629                        return rewrite_one_ok;
1630                if (!p->parents)
1631                        return rewrite_one_noparents;
1632                *pp = p->parents->item;
1633        }
1634}
1635
1636static int rewrite_parents(struct rev_info *revs, struct commit *commit)
1637{
1638        struct commit_list **pp = &commit->parents;
1639        while (*pp) {
1640                struct commit_list *parent = *pp;
1641                switch (rewrite_one(revs, &parent->item)) {
1642                case rewrite_one_ok:
1643                        break;
1644                case rewrite_one_noparents:
1645                        *pp = parent->next;
1646                        continue;
1647                case rewrite_one_error:
1648                        return -1;
1649                }
1650                pp = &parent->next;
1651        }
1652        remove_duplicate_parents(commit);
1653        return 0;
1654}
1655
1656static int commit_match(struct commit *commit, struct rev_info *opt)
1657{
1658        if (!opt->grep_filter.pattern_list)
1659                return 1;
1660        return grep_buffer(&opt->grep_filter,
1661                           NULL, /* we say nothing, not even filename */
1662                           commit->buffer, strlen(commit->buffer));
1663}
1664
1665static inline int want_ancestry(struct rev_info *revs)
1666{
1667        return (revs->rewrite_parents || revs->children.name);
1668}
1669
1670enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
1671{
1672        if (commit->object.flags & SHOWN)
1673                return commit_ignore;
1674        if (revs->unpacked && has_sha1_pack(commit->object.sha1))
1675                return commit_ignore;
1676        if (revs->show_all)
1677                return commit_show;
1678        if (commit->object.flags & UNINTERESTING)
1679                return commit_ignore;
1680        if (revs->min_age != -1 && (commit->date > revs->min_age))
1681                return commit_ignore;
1682        if (revs->no_merges && commit->parents && commit->parents->next)
1683                return commit_ignore;
1684        if (!commit_match(commit, revs))
1685                return commit_ignore;
1686        if (revs->prune && revs->dense) {
1687                /* Commit without changes? */
1688                if (commit->object.flags & TREESAME) {
1689                        /* drop merges unless we want parenthood */
1690                        if (!want_ancestry(revs))
1691                                return commit_ignore;
1692                        /* non-merge - always ignore it */
1693                        if (!commit->parents || !commit->parents->next)
1694                                return commit_ignore;
1695                }
1696                if (want_ancestry(revs) && rewrite_parents(revs, commit) < 0)
1697                        return commit_error;
1698        }
1699        return commit_show;
1700}
1701
1702static struct commit *get_revision_1(struct rev_info *revs)
1703{
1704        if (!revs->commits)
1705                return NULL;
1706
1707        do {
1708                struct commit_list *entry = revs->commits;
1709                struct commit *commit = entry->item;
1710
1711                revs->commits = entry->next;
1712                free(entry);
1713
1714                if (revs->reflog_info)
1715                        fake_reflog_parent(revs->reflog_info, commit);
1716
1717                /*
1718                 * If we haven't done the list limiting, we need to look at
1719                 * the parents here. We also need to do the date-based limiting
1720                 * that we'd otherwise have done in limit_list().
1721                 */
1722                if (!revs->limited) {
1723                        if (revs->max_age != -1 &&
1724                            (commit->date < revs->max_age))
1725                                continue;
1726                        if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0)
1727                                die("Failed to traverse parents of commit %s",
1728                                    sha1_to_hex(commit->object.sha1));
1729                }
1730
1731                switch (simplify_commit(revs, commit)) {
1732                case commit_ignore:
1733                        continue;
1734                case commit_error:
1735                        die("Failed to simplify parents of commit %s",
1736                            sha1_to_hex(commit->object.sha1));
1737                default:
1738                        return commit;
1739                }
1740        } while (revs->commits);
1741        return NULL;
1742}
1743
1744static void gc_boundary(struct object_array *array)
1745{
1746        unsigned nr = array->nr;
1747        unsigned alloc = array->alloc;
1748        struct object_array_entry *objects = array->objects;
1749
1750        if (alloc <= nr) {
1751                unsigned i, j;
1752                for (i = j = 0; i < nr; i++) {
1753                        if (objects[i].item->flags & SHOWN)
1754                                continue;
1755                        if (i != j)
1756                                objects[j] = objects[i];
1757                        j++;
1758                }
1759                for (i = j; i < nr; i++)
1760                        objects[i].item = NULL;
1761                array->nr = j;
1762        }
1763}
1764
1765static void create_boundary_commit_list(struct rev_info *revs)
1766{
1767        unsigned i;
1768        struct commit *c;
1769        struct object_array *array = &revs->boundary_commits;
1770        struct object_array_entry *objects = array->objects;
1771
1772        /*
1773         * If revs->commits is non-NULL at this point, an error occurred in
1774         * get_revision_1().  Ignore the error and continue printing the
1775         * boundary commits anyway.  (This is what the code has always
1776         * done.)
1777         */
1778        if (revs->commits) {
1779                free_commit_list(revs->commits);
1780                revs->commits = NULL;
1781        }
1782
1783        /*
1784         * Put all of the actual boundary commits from revs->boundary_commits
1785         * into revs->commits
1786         */
1787        for (i = 0; i < array->nr; i++) {
1788                c = (struct commit *)(objects[i].item);
1789                if (!c)
1790                        continue;
1791                if (!(c->object.flags & CHILD_SHOWN))
1792                        continue;
1793                if (c->object.flags & (SHOWN | BOUNDARY))
1794                        continue;
1795                c->object.flags |= BOUNDARY;
1796                commit_list_insert(c, &revs->commits);
1797        }
1798
1799        /*
1800         * If revs->topo_order is set, sort the boundary commits
1801         * in topological order
1802         */
1803        sort_in_topological_order(&revs->commits, revs->lifo);
1804}
1805
1806static struct commit *get_revision_internal(struct rev_info *revs)
1807{
1808        struct commit *c = NULL;
1809        struct commit_list *l;
1810
1811        if (revs->boundary == 2) {
1812                /*
1813                 * All of the normal commits have already been returned,
1814                 * and we are now returning boundary commits.
1815                 * create_boundary_commit_list() has populated
1816                 * revs->commits with the remaining commits to return.
1817                 */
1818                c = pop_commit(&revs->commits);
1819                if (c)
1820                        c->object.flags |= SHOWN;
1821                return c;
1822        }
1823
1824        /*
1825         * Now pick up what they want to give us
1826         */
1827        c = get_revision_1(revs);
1828        if (c) {
1829                while (0 < revs->skip_count) {
1830                        revs->skip_count--;
1831                        c = get_revision_1(revs);
1832                        if (!c)
1833                                break;
1834                }
1835        }
1836
1837        /*
1838         * Check the max_count.
1839         */
1840        switch (revs->max_count) {
1841        case -1:
1842                break;
1843        case 0:
1844                c = NULL;
1845                break;
1846        default:
1847                revs->max_count--;
1848        }
1849
1850        if (c)
1851                c->object.flags |= SHOWN;
1852
1853        if (!revs->boundary) {
1854                return c;
1855        }
1856
1857        if (!c) {
1858                /*
1859                 * get_revision_1() runs out the commits, and
1860                 * we are done computing the boundaries.
1861                 * switch to boundary commits output mode.
1862                 */
1863                revs->boundary = 2;
1864
1865                /*
1866                 * Update revs->commits to contain the list of
1867                 * boundary commits.
1868                 */
1869                create_boundary_commit_list(revs);
1870
1871                return get_revision_internal(revs);
1872        }
1873
1874        /*
1875         * boundary commits are the commits that are parents of the
1876         * ones we got from get_revision_1() but they themselves are
1877         * not returned from get_revision_1().  Before returning
1878         * 'c', we need to mark its parents that they could be boundaries.
1879         */
1880
1881        for (l = c->parents; l; l = l->next) {
1882                struct object *p;
1883                p = &(l->item->object);
1884                if (p->flags & (CHILD_SHOWN | SHOWN))
1885                        continue;
1886                p->flags |= CHILD_SHOWN;
1887                gc_boundary(&revs->boundary_commits);
1888                add_object_array(p, NULL, &revs->boundary_commits);
1889        }
1890
1891        return c;
1892}
1893
1894struct commit *get_revision(struct rev_info *revs)
1895{
1896        struct commit *c;
1897        struct commit_list *reversed;
1898
1899        if (revs->reverse) {
1900                reversed = NULL;
1901                while ((c = get_revision_internal(revs))) {
1902                        commit_list_insert(c, &reversed);
1903                }
1904                revs->commits = reversed;
1905                revs->reverse = 0;
1906                revs->reverse_output_stage = 1;
1907        }
1908
1909        if (revs->reverse_output_stage)
1910                return pop_commit(&revs->commits);
1911
1912        c = get_revision_internal(revs);
1913        if (c && revs->graph)
1914                graph_update(revs->graph, c);
1915        return c;
1916}