revision.con commit Merge branch 'ph/parseopt-step-blame' (fa6200f)
   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
  15volatile show_early_output_fn_t show_early_output;
  16
  17static char *path_name(struct name_path *path, const char *name)
  18{
  19        struct name_path *p;
  20        char *n, *m;
  21        int nlen = strlen(name);
  22        int len = nlen + 1;
  23
  24        for (p = path; p; p = p->up) {
  25                if (p->elem_len)
  26                        len += p->elem_len + 1;
  27        }
  28        n = xmalloc(len);
  29        m = n + len - (nlen + 1);
  30        strcpy(m, name);
  31        for (p = path; p; p = p->up) {
  32                if (p->elem_len) {
  33                        m -= p->elem_len + 1;
  34                        memcpy(m, p->elem, p->elem_len);
  35                        m[p->elem_len] = '/';
  36                }
  37        }
  38        return n;
  39}
  40
  41void add_object(struct object *obj,
  42                struct object_array *p,
  43                struct name_path *path,
  44                const char *name)
  45{
  46        add_object_array(obj, path_name(path, name), p);
  47}
  48
  49static void mark_blob_uninteresting(struct blob *blob)
  50{
  51        if (!blob)
  52                return;
  53        if (blob->object.flags & UNINTERESTING)
  54                return;
  55        blob->object.flags |= UNINTERESTING;
  56}
  57
  58void mark_tree_uninteresting(struct tree *tree)
  59{
  60        struct tree_desc desc;
  61        struct name_entry entry;
  62        struct object *obj = &tree->object;
  63
  64        if (!tree)
  65                return;
  66        if (obj->flags & UNINTERESTING)
  67                return;
  68        obj->flags |= UNINTERESTING;
  69        if (!has_sha1_file(obj->sha1))
  70                return;
  71        if (parse_tree(tree) < 0)
  72                die("bad tree %s", sha1_to_hex(obj->sha1));
  73
  74        init_tree_desc(&desc, tree->buffer, tree->size);
  75        while (tree_entry(&desc, &entry)) {
  76                switch (object_type(entry.mode)) {
  77                case OBJ_TREE:
  78                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  79                        break;
  80                case OBJ_BLOB:
  81                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  82                        break;
  83                default:
  84                        /* Subproject commit - not in this repository */
  85                        break;
  86                }
  87        }
  88
  89        /*
  90         * We don't care about the tree any more
  91         * after it has been marked uninteresting.
  92         */
  93        free(tree->buffer);
  94        tree->buffer = NULL;
  95}
  96
  97void mark_parents_uninteresting(struct commit *commit)
  98{
  99        struct commit_list *parents = commit->parents;
 100
 101        while (parents) {
 102                struct commit *commit = parents->item;
 103                if (!(commit->object.flags & UNINTERESTING)) {
 104                        commit->object.flags |= UNINTERESTING;
 105
 106                        /*
 107                         * Normally we haven't parsed the parent
 108                         * yet, so we won't have a parent of a parent
 109                         * here. However, it may turn out that we've
 110                         * reached this commit some other way (where it
 111                         * wasn't uninteresting), in which case we need
 112                         * to mark its parents recursively too..
 113                         */
 114                        if (commit->parents)
 115                                mark_parents_uninteresting(commit);
 116                }
 117
 118                /*
 119                 * A missing commit is ok iff its parent is marked
 120                 * uninteresting.
 121                 *
 122                 * We just mark such a thing parsed, so that when
 123                 * it is popped next time around, we won't be trying
 124                 * to parse it and get an error.
 125                 */
 126                if (!has_sha1_file(commit->object.sha1))
 127                        commit->object.parsed = 1;
 128                parents = parents->next;
 129        }
 130}
 131
 132static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
 133{
 134        if (revs->no_walk && (obj->flags & UNINTERESTING))
 135                die("object ranges do not make sense when not walking revisions");
 136        if (revs->reflog_info && obj->type == OBJ_COMMIT &&
 137                        add_reflog_for_walk(revs->reflog_info,
 138                                (struct commit *)obj, name))
 139                return;
 140        add_object_array_with_mode(obj, name, &revs->pending, mode);
 141}
 142
 143void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 144{
 145        add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
 146}
 147
 148void add_head_to_pending(struct rev_info *revs)
 149{
 150        unsigned char sha1[20];
 151        struct object *obj;
 152        if (get_sha1("HEAD", sha1))
 153                return;
 154        obj = parse_object(sha1);
 155        if (!obj)
 156                return;
 157        add_pending_object(revs, obj, "HEAD");
 158}
 159
 160static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 161{
 162        struct object *object;
 163
 164        object = parse_object(sha1);
 165        if (!object)
 166                die("bad object %s", name);
 167        object->flags |= flags;
 168        return object;
 169}
 170
 171static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 172{
 173        unsigned long flags = object->flags;
 174
 175        /*
 176         * Tag object? Look what it points to..
 177         */
 178        while (object->type == OBJ_TAG) {
 179                struct tag *tag = (struct tag *) object;
 180                if (revs->tag_objects && !(flags & UNINTERESTING))
 181                        add_pending_object(revs, object, tag->tag);
 182                if (!tag->tagged)
 183                        die("bad tag");
 184                object = parse_object(tag->tagged->sha1);
 185                if (!object)
 186                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 187        }
 188
 189        /*
 190         * Commit object? Just return it, we'll do all the complex
 191         * reachability crud.
 192         */
 193        if (object->type == OBJ_COMMIT) {
 194                struct commit *commit = (struct commit *)object;
 195                if (parse_commit(commit) < 0)
 196                        die("unable to parse commit %s", name);
 197                if (flags & UNINTERESTING) {
 198                        commit->object.flags |= UNINTERESTING;
 199                        mark_parents_uninteresting(commit);
 200                        revs->limited = 1;
 201                }
 202                return commit;
 203        }
 204
 205        /*
 206         * Tree object? Either mark it uniniteresting, or add it
 207         * to the list of objects to look at later..
 208         */
 209        if (object->type == OBJ_TREE) {
 210                struct tree *tree = (struct tree *)object;
 211                if (!revs->tree_objects)
 212                        return NULL;
 213                if (flags & UNINTERESTING) {
 214                        mark_tree_uninteresting(tree);
 215                        return NULL;
 216                }
 217                add_pending_object(revs, object, "");
 218                return NULL;
 219        }
 220
 221        /*
 222         * Blob object? You know the drill by now..
 223         */
 224        if (object->type == OBJ_BLOB) {
 225                struct blob *blob = (struct blob *)object;
 226                if (!revs->blob_objects)
 227                        return NULL;
 228                if (flags & UNINTERESTING) {
 229                        mark_blob_uninteresting(blob);
 230                        return NULL;
 231                }
 232                add_pending_object(revs, object, "");
 233                return NULL;
 234        }
 235        die("%s is unknown object", name);
 236}
 237
 238static int everybody_uninteresting(struct commit_list *orig)
 239{
 240        struct commit_list *list = orig;
 241        while (list) {
 242                struct commit *commit = list->item;
 243                list = list->next;
 244                if (commit->object.flags & UNINTERESTING)
 245                        continue;
 246                return 0;
 247        }
 248        return 1;
 249}
 250
 251/*
 252 * The goal is to get REV_TREE_NEW as the result only if the
 253 * diff consists of all '+' (and no other changes), and
 254 * REV_TREE_DIFFERENT otherwise (of course if the trees are
 255 * the same we want REV_TREE_SAME).  That means that once we
 256 * get to REV_TREE_DIFFERENT, we do not have to look any further.
 257 */
 258static int tree_difference = REV_TREE_SAME;
 259
 260static void file_add_remove(struct diff_options *options,
 261                    int addremove, unsigned mode,
 262                    const unsigned char *sha1,
 263                    const char *base, const char *path)
 264{
 265        int diff = REV_TREE_DIFFERENT;
 266
 267        /*
 268         * Is it an add of a new file? It means that the old tree
 269         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 270         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 271         * (and if it already was "REV_TREE_NEW", we'll keep it
 272         * "REV_TREE_NEW" of course).
 273         */
 274        if (addremove == '+') {
 275                diff = tree_difference;
 276                if (diff != REV_TREE_SAME)
 277                        return;
 278                diff = REV_TREE_NEW;
 279        }
 280        tree_difference = diff;
 281        if (tree_difference == REV_TREE_DIFFERENT)
 282                DIFF_OPT_SET(options, HAS_CHANGES);
 283}
 284
 285static void file_change(struct diff_options *options,
 286                 unsigned old_mode, unsigned new_mode,
 287                 const unsigned char *old_sha1,
 288                 const unsigned char *new_sha1,
 289                 const char *base, const char *path)
 290{
 291        tree_difference = REV_TREE_DIFFERENT;
 292        DIFF_OPT_SET(options, HAS_CHANGES);
 293}
 294
 295static int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 296{
 297        if (!t1)
 298                return REV_TREE_NEW;
 299        if (!t2)
 300                return REV_TREE_DIFFERENT;
 301        tree_difference = REV_TREE_SAME;
 302        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 303        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 304                           &revs->pruning) < 0)
 305                return REV_TREE_DIFFERENT;
 306        return tree_difference;
 307}
 308
 309static int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 310{
 311        int retval;
 312        void *tree;
 313        unsigned long size;
 314        struct tree_desc empty, real;
 315
 316        if (!t1)
 317                return 0;
 318
 319        tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
 320        if (!tree)
 321                return 0;
 322        init_tree_desc(&real, tree, size);
 323        init_tree_desc(&empty, "", 0);
 324
 325        tree_difference = REV_TREE_SAME;
 326        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
 327        retval = diff_tree(&empty, &real, "", &revs->pruning);
 328        free(tree);
 329
 330        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 331}
 332
 333static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 334{
 335        struct commit_list **pp, *parent;
 336        int tree_changed = 0, tree_same = 0;
 337
 338        /*
 339         * If we don't do pruning, everything is interesting
 340         */
 341        if (!revs->prune)
 342                return;
 343
 344        if (!commit->tree)
 345                return;
 346
 347        if (!commit->parents) {
 348                if (rev_same_tree_as_empty(revs, commit->tree))
 349                        commit->object.flags |= TREESAME;
 350                return;
 351        }
 352
 353        /*
 354         * Normal non-merge commit? If we don't want to make the
 355         * history dense, we consider it always to be a change..
 356         */
 357        if (!revs->dense && !commit->parents->next)
 358                return;
 359
 360        pp = &commit->parents;
 361        while ((parent = *pp) != NULL) {
 362                struct commit *p = parent->item;
 363
 364                if (parse_commit(p) < 0)
 365                        die("cannot simplify commit %s (because of %s)",
 366                            sha1_to_hex(commit->object.sha1),
 367                            sha1_to_hex(p->object.sha1));
 368                switch (rev_compare_tree(revs, p->tree, commit->tree)) {
 369                case REV_TREE_SAME:
 370                        tree_same = 1;
 371                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 372                                /* Even if a merge with an uninteresting
 373                                 * side branch brought the entire change
 374                                 * we are interested in, we do not want
 375                                 * to lose the other branches of this
 376                                 * merge, so we just keep going.
 377                                 */
 378                                pp = &parent->next;
 379                                continue;
 380                        }
 381                        parent->next = NULL;
 382                        commit->parents = parent;
 383                        commit->object.flags |= TREESAME;
 384                        return;
 385
 386                case REV_TREE_NEW:
 387                        if (revs->remove_empty_trees &&
 388                            rev_same_tree_as_empty(revs, p->tree)) {
 389                                /* We are adding all the specified
 390                                 * paths from this parent, so the
 391                                 * history beyond this parent is not
 392                                 * interesting.  Remove its parents
 393                                 * (they are grandparents for us).
 394                                 * IOW, we pretend this parent is a
 395                                 * "root" commit.
 396                                 */
 397                                if (parse_commit(p) < 0)
 398                                        die("cannot simplify commit %s (invalid %s)",
 399                                            sha1_to_hex(commit->object.sha1),
 400                                            sha1_to_hex(p->object.sha1));
 401                                p->parents = NULL;
 402                        }
 403                /* fallthrough */
 404                case REV_TREE_DIFFERENT:
 405                        tree_changed = 1;
 406                        pp = &parent->next;
 407                        continue;
 408                }
 409                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 410        }
 411        if (tree_changed && !tree_same)
 412                return;
 413        commit->object.flags |= TREESAME;
 414}
 415
 416static int add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 417{
 418        struct commit_list *parent = commit->parents;
 419        unsigned left_flag;
 420
 421        if (commit->object.flags & ADDED)
 422                return 0;
 423        commit->object.flags |= ADDED;
 424
 425        /*
 426         * If the commit is uninteresting, don't try to
 427         * prune parents - we want the maximal uninteresting
 428         * set.
 429         *
 430         * Normally we haven't parsed the parent
 431         * yet, so we won't have a parent of a parent
 432         * here. However, it may turn out that we've
 433         * reached this commit some other way (where it
 434         * wasn't uninteresting), in which case we need
 435         * to mark its parents recursively too..
 436         */
 437        if (commit->object.flags & UNINTERESTING) {
 438                while (parent) {
 439                        struct commit *p = parent->item;
 440                        parent = parent->next;
 441                        if (parse_commit(p) < 0)
 442                                return -1;
 443                        p->object.flags |= UNINTERESTING;
 444                        if (p->parents)
 445                                mark_parents_uninteresting(p);
 446                        if (p->object.flags & SEEN)
 447                                continue;
 448                        p->object.flags |= SEEN;
 449                        insert_by_date(p, list);
 450                }
 451                return 0;
 452        }
 453
 454        /*
 455         * Ok, the commit wasn't uninteresting. Try to
 456         * simplify the commit history and find the parent
 457         * that has no differences in the path set if one exists.
 458         */
 459        try_to_simplify_commit(revs, commit);
 460
 461        if (revs->no_walk)
 462                return 0;
 463
 464        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 465
 466        for (parent = commit->parents; parent; parent = parent->next) {
 467                struct commit *p = parent->item;
 468
 469                if (parse_commit(p) < 0)
 470                        return -1;
 471                p->object.flags |= left_flag;
 472                if (!(p->object.flags & SEEN)) {
 473                        p->object.flags |= SEEN;
 474                        insert_by_date(p, list);
 475                }
 476                if(revs->first_parent_only)
 477                        break;
 478        }
 479        return 0;
 480}
 481
 482static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 483{
 484        struct commit_list *p;
 485        int left_count = 0, right_count = 0;
 486        int left_first;
 487        struct patch_ids ids;
 488
 489        /* First count the commits on the left and on the right */
 490        for (p = list; p; p = p->next) {
 491                struct commit *commit = p->item;
 492                unsigned flags = commit->object.flags;
 493                if (flags & BOUNDARY)
 494                        ;
 495                else if (flags & SYMMETRIC_LEFT)
 496                        left_count++;
 497                else
 498                        right_count++;
 499        }
 500
 501        left_first = left_count < right_count;
 502        init_patch_ids(&ids);
 503        if (revs->diffopt.nr_paths) {
 504                ids.diffopts.nr_paths = revs->diffopt.nr_paths;
 505                ids.diffopts.paths = revs->diffopt.paths;
 506                ids.diffopts.pathlens = revs->diffopt.pathlens;
 507        }
 508
 509        /* Compute patch-ids for one side */
 510        for (p = list; p; p = p->next) {
 511                struct commit *commit = p->item;
 512                unsigned flags = commit->object.flags;
 513
 514                if (flags & BOUNDARY)
 515                        continue;
 516                /*
 517                 * If we have fewer left, left_first is set and we omit
 518                 * commits on the right branch in this loop.  If we have
 519                 * fewer right, we skip the left ones.
 520                 */
 521                if (left_first != !!(flags & SYMMETRIC_LEFT))
 522                        continue;
 523                commit->util = add_commit_patch_id(commit, &ids);
 524        }
 525
 526        /* Check the other side */
 527        for (p = list; p; p = p->next) {
 528                struct commit *commit = p->item;
 529                struct patch_id *id;
 530                unsigned flags = commit->object.flags;
 531
 532                if (flags & BOUNDARY)
 533                        continue;
 534                /*
 535                 * If we have fewer left, left_first is set and we omit
 536                 * commits on the left branch in this loop.
 537                 */
 538                if (left_first == !!(flags & SYMMETRIC_LEFT))
 539                        continue;
 540
 541                /*
 542                 * Have we seen the same patch id?
 543                 */
 544                id = has_commit_patch_id(commit, &ids);
 545                if (!id)
 546                        continue;
 547                id->seen = 1;
 548                commit->object.flags |= SHOWN;
 549        }
 550
 551        /* Now check the original side for seen ones */
 552        for (p = list; p; p = p->next) {
 553                struct commit *commit = p->item;
 554                struct patch_id *ent;
 555
 556                ent = commit->util;
 557                if (!ent)
 558                        continue;
 559                if (ent->seen)
 560                        commit->object.flags |= SHOWN;
 561                commit->util = NULL;
 562        }
 563
 564        free_patch_ids(&ids);
 565}
 566
 567/* How many extra uninteresting commits we want to see.. */
 568#define SLOP 5
 569
 570static int still_interesting(struct commit_list *src, unsigned long date, int slop)
 571{
 572        /*
 573         * No source list at all? We're definitely done..
 574         */
 575        if (!src)
 576                return 0;
 577
 578        /*
 579         * Does the destination list contain entries with a date
 580         * before the source list? Definitely _not_ done.
 581         */
 582        if (date < src->item->date)
 583                return SLOP;
 584
 585        /*
 586         * Does the source list still have interesting commits in
 587         * it? Definitely not done..
 588         */
 589        if (!everybody_uninteresting(src))
 590                return SLOP;
 591
 592        /* Ok, we're closing in.. */
 593        return slop-1;
 594}
 595
 596static int limit_list(struct rev_info *revs)
 597{
 598        int slop = SLOP;
 599        unsigned long date = ~0ul;
 600        struct commit_list *list = revs->commits;
 601        struct commit_list *newlist = NULL;
 602        struct commit_list **p = &newlist;
 603
 604        while (list) {
 605                struct commit_list *entry = list;
 606                struct commit *commit = list->item;
 607                struct object *obj = &commit->object;
 608                show_early_output_fn_t show;
 609
 610                list = list->next;
 611                free(entry);
 612
 613                if (revs->max_age != -1 && (commit->date < revs->max_age))
 614                        obj->flags |= UNINTERESTING;
 615                if (add_parents_to_list(revs, commit, &list) < 0)
 616                        return -1;
 617                if (obj->flags & UNINTERESTING) {
 618                        mark_parents_uninteresting(commit);
 619                        if (revs->show_all)
 620                                p = &commit_list_insert(commit, p)->next;
 621                        slop = still_interesting(list, date, slop);
 622                        if (slop)
 623                                continue;
 624                        /* If showing all, add the whole pending list to the end */
 625                        if (revs->show_all)
 626                                *p = list;
 627                        break;
 628                }
 629                if (revs->min_age != -1 && (commit->date > revs->min_age))
 630                        continue;
 631                date = commit->date;
 632                p = &commit_list_insert(commit, p)->next;
 633
 634                show = show_early_output;
 635                if (!show)
 636                        continue;
 637
 638                show(revs, newlist);
 639                show_early_output = NULL;
 640        }
 641        if (revs->cherry_pick)
 642                cherry_pick_list(newlist, revs);
 643
 644        revs->commits = newlist;
 645        return 0;
 646}
 647
 648struct all_refs_cb {
 649        int all_flags;
 650        int warned_bad_reflog;
 651        struct rev_info *all_revs;
 652        const char *name_for_errormsg;
 653};
 654
 655static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 656{
 657        struct all_refs_cb *cb = cb_data;
 658        struct object *object = get_reference(cb->all_revs, path, sha1,
 659                                              cb->all_flags);
 660        add_pending_object(cb->all_revs, object, path);
 661        return 0;
 662}
 663
 664static void handle_refs(struct rev_info *revs, unsigned flags,
 665                int (*for_each)(each_ref_fn, void *))
 666{
 667        struct all_refs_cb cb;
 668        cb.all_revs = revs;
 669        cb.all_flags = flags;
 670        for_each(handle_one_ref, &cb);
 671}
 672
 673static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 674{
 675        struct all_refs_cb *cb = cb_data;
 676        if (!is_null_sha1(sha1)) {
 677                struct object *o = parse_object(sha1);
 678                if (o) {
 679                        o->flags |= cb->all_flags;
 680                        add_pending_object(cb->all_revs, o, "");
 681                }
 682                else if (!cb->warned_bad_reflog) {
 683                        warning("reflog of '%s' references pruned commits",
 684                                cb->name_for_errormsg);
 685                        cb->warned_bad_reflog = 1;
 686                }
 687        }
 688}
 689
 690static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 691                const char *email, unsigned long timestamp, int tz,
 692                const char *message, void *cb_data)
 693{
 694        handle_one_reflog_commit(osha1, cb_data);
 695        handle_one_reflog_commit(nsha1, cb_data);
 696        return 0;
 697}
 698
 699static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 700{
 701        struct all_refs_cb *cb = cb_data;
 702        cb->warned_bad_reflog = 0;
 703        cb->name_for_errormsg = path;
 704        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
 705        return 0;
 706}
 707
 708static void handle_reflog(struct rev_info *revs, unsigned flags)
 709{
 710        struct all_refs_cb cb;
 711        cb.all_revs = revs;
 712        cb.all_flags = flags;
 713        for_each_reflog(handle_one_reflog, &cb);
 714}
 715
 716static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 717{
 718        unsigned char sha1[20];
 719        struct object *it;
 720        struct commit *commit;
 721        struct commit_list *parents;
 722
 723        if (*arg == '^') {
 724                flags ^= UNINTERESTING;
 725                arg++;
 726        }
 727        if (get_sha1(arg, sha1))
 728                return 0;
 729        while (1) {
 730                it = get_reference(revs, arg, sha1, 0);
 731                if (it->type != OBJ_TAG)
 732                        break;
 733                if (!((struct tag*)it)->tagged)
 734                        return 0;
 735                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 736        }
 737        if (it->type != OBJ_COMMIT)
 738                return 0;
 739        commit = (struct commit *)it;
 740        for (parents = commit->parents; parents; parents = parents->next) {
 741                it = &parents->item->object;
 742                it->flags |= flags;
 743                add_pending_object(revs, it, arg);
 744        }
 745        return 1;
 746}
 747
 748void init_revisions(struct rev_info *revs, const char *prefix)
 749{
 750        memset(revs, 0, sizeof(*revs));
 751
 752        revs->abbrev = DEFAULT_ABBREV;
 753        revs->ignore_merges = 1;
 754        revs->simplify_history = 1;
 755        DIFF_OPT_SET(&revs->pruning, RECURSIVE);
 756        DIFF_OPT_SET(&revs->pruning, QUIET);
 757        revs->pruning.add_remove = file_add_remove;
 758        revs->pruning.change = file_change;
 759        revs->lifo = 1;
 760        revs->dense = 1;
 761        revs->prefix = prefix;
 762        revs->max_age = -1;
 763        revs->min_age = -1;
 764        revs->skip_count = -1;
 765        revs->max_count = -1;
 766
 767        revs->commit_format = CMIT_FMT_DEFAULT;
 768
 769        diff_setup(&revs->diffopt);
 770        if (prefix && !revs->diffopt.prefix) {
 771                revs->diffopt.prefix = prefix;
 772                revs->diffopt.prefix_length = strlen(prefix);
 773        }
 774}
 775
 776static void add_pending_commit_list(struct rev_info *revs,
 777                                    struct commit_list *commit_list,
 778                                    unsigned int flags)
 779{
 780        while (commit_list) {
 781                struct object *object = &commit_list->item->object;
 782                object->flags |= flags;
 783                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 784                commit_list = commit_list->next;
 785        }
 786}
 787
 788static void prepare_show_merge(struct rev_info *revs)
 789{
 790        struct commit_list *bases;
 791        struct commit *head, *other;
 792        unsigned char sha1[20];
 793        const char **prune = NULL;
 794        int i, prune_num = 1; /* counting terminating NULL */
 795
 796        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 797                die("--merge without HEAD?");
 798        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 799                die("--merge without MERGE_HEAD?");
 800        add_pending_object(revs, &head->object, "HEAD");
 801        add_pending_object(revs, &other->object, "MERGE_HEAD");
 802        bases = get_merge_bases(head, other, 1);
 803        add_pending_commit_list(revs, bases, UNINTERESTING);
 804        free_commit_list(bases);
 805        head->object.flags |= SYMMETRIC_LEFT;
 806
 807        if (!active_nr)
 808                read_cache();
 809        for (i = 0; i < active_nr; i++) {
 810                struct cache_entry *ce = active_cache[i];
 811                if (!ce_stage(ce))
 812                        continue;
 813                if (ce_path_match(ce, revs->prune_data)) {
 814                        prune_num++;
 815                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
 816                        prune[prune_num-2] = ce->name;
 817                        prune[prune_num-1] = NULL;
 818                }
 819                while ((i+1 < active_nr) &&
 820                       ce_same_name(ce, active_cache[i+1]))
 821                        i++;
 822        }
 823        revs->prune_data = prune;
 824        revs->limited = 1;
 825}
 826
 827int handle_revision_arg(const char *arg, struct rev_info *revs,
 828                        int flags,
 829                        int cant_be_filename)
 830{
 831        unsigned mode;
 832        char *dotdot;
 833        struct object *object;
 834        unsigned char sha1[20];
 835        int local_flags;
 836
 837        dotdot = strstr(arg, "..");
 838        if (dotdot) {
 839                unsigned char from_sha1[20];
 840                const char *next = dotdot + 2;
 841                const char *this = arg;
 842                int symmetric = *next == '.';
 843                unsigned int flags_exclude = flags ^ UNINTERESTING;
 844
 845                *dotdot = 0;
 846                next += symmetric;
 847
 848                if (!*next)
 849                        next = "HEAD";
 850                if (dotdot == arg)
 851                        this = "HEAD";
 852                if (!get_sha1(this, from_sha1) &&
 853                    !get_sha1(next, sha1)) {
 854                        struct commit *a, *b;
 855                        struct commit_list *exclude;
 856
 857                        a = lookup_commit_reference(from_sha1);
 858                        b = lookup_commit_reference(sha1);
 859                        if (!a || !b) {
 860                                die(symmetric ?
 861                                    "Invalid symmetric difference expression %s...%s" :
 862                                    "Invalid revision range %s..%s",
 863                                    arg, next);
 864                        }
 865
 866                        if (!cant_be_filename) {
 867                                *dotdot = '.';
 868                                verify_non_filename(revs->prefix, arg);
 869                        }
 870
 871                        if (symmetric) {
 872                                exclude = get_merge_bases(a, b, 1);
 873                                add_pending_commit_list(revs, exclude,
 874                                                        flags_exclude);
 875                                free_commit_list(exclude);
 876                                a->object.flags |= flags | SYMMETRIC_LEFT;
 877                        } else
 878                                a->object.flags |= flags_exclude;
 879                        b->object.flags |= flags;
 880                        add_pending_object(revs, &a->object, this);
 881                        add_pending_object(revs, &b->object, next);
 882                        return 0;
 883                }
 884                *dotdot = '.';
 885        }
 886        dotdot = strstr(arg, "^@");
 887        if (dotdot && !dotdot[2]) {
 888                *dotdot = 0;
 889                if (add_parents_only(revs, arg, flags))
 890                        return 0;
 891                *dotdot = '^';
 892        }
 893        dotdot = strstr(arg, "^!");
 894        if (dotdot && !dotdot[2]) {
 895                *dotdot = 0;
 896                if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
 897                        *dotdot = '^';
 898        }
 899
 900        local_flags = 0;
 901        if (*arg == '^') {
 902                local_flags = UNINTERESTING;
 903                arg++;
 904        }
 905        if (get_sha1_with_mode(arg, sha1, &mode))
 906                return -1;
 907        if (!cant_be_filename)
 908                verify_non_filename(revs->prefix, arg);
 909        object = get_reference(revs, arg, sha1, flags ^ local_flags);
 910        add_pending_object_with_mode(revs, object, arg, mode);
 911        return 0;
 912}
 913
 914void read_revisions_from_stdin(struct rev_info *revs)
 915{
 916        char line[1000];
 917
 918        while (fgets(line, sizeof(line), stdin) != NULL) {
 919                int len = strlen(line);
 920                if (len && line[len - 1] == '\n')
 921                        line[--len] = '\0';
 922                if (!len)
 923                        break;
 924                if (line[0] == '-')
 925                        die("options not supported in --stdin mode");
 926                if (handle_revision_arg(line, revs, 0, 1))
 927                        die("bad revision '%s'", line);
 928        }
 929}
 930
 931static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 932{
 933        if (!revs->grep_filter) {
 934                struct grep_opt *opt = xcalloc(1, sizeof(*opt));
 935                opt->status_only = 1;
 936                opt->pattern_tail = &(opt->pattern_list);
 937                opt->regflags = REG_NEWLINE;
 938                revs->grep_filter = opt;
 939        }
 940        append_grep_pattern(revs->grep_filter, ptn,
 941                            "command line", 0, what);
 942}
 943
 944static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
 945{
 946        char *pat;
 947        const char *prefix;
 948        int patlen, fldlen;
 949
 950        fldlen = strlen(field);
 951        patlen = strlen(pattern);
 952        pat = xmalloc(patlen + fldlen + 10);
 953        prefix = ".*";
 954        if (*pattern == '^') {
 955                prefix = "";
 956                pattern++;
 957        }
 958        sprintf(pat, "^%s %s%s", field, prefix, pattern);
 959        add_grep(revs, pat, GREP_PATTERN_HEAD);
 960}
 961
 962static void add_message_grep(struct rev_info *revs, const char *pattern)
 963{
 964        add_grep(revs, pattern, GREP_PATTERN_BODY);
 965}
 966
 967static void add_ignore_packed(struct rev_info *revs, const char *name)
 968{
 969        int num = ++revs->num_ignore_packed;
 970
 971        revs->ignore_packed = xrealloc(revs->ignore_packed,
 972                                       sizeof(const char **) * (num + 1));
 973        revs->ignore_packed[num-1] = name;
 974        revs->ignore_packed[num] = NULL;
 975}
 976
 977static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
 978                               int *unkc, const char **unkv)
 979{
 980        const char *arg = argv[0];
 981
 982        /* pseudo revision arguments */
 983        if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
 984            !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
 985            !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
 986            !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk"))
 987        {
 988                unkv[(*unkc)++] = arg;
 989                return 0;
 990        }
 991
 992        if (!prefixcmp(arg, "--max-count=")) {
 993                revs->max_count = atoi(arg + 12);
 994        } else if (!prefixcmp(arg, "--skip=")) {
 995                revs->skip_count = atoi(arg + 7);
 996        } else if ((*arg == '-') && isdigit(arg[1])) {
 997        /* accept -<digit>, like traditional "head" */
 998                revs->max_count = atoi(arg + 1);
 999        } else if (!strcmp(arg, "-n")) {
1000                if (argc <= 1)
1001                        return error("-n requires an argument");
1002                revs->max_count = atoi(argv[1]);
1003                return 2;
1004        } else if (!prefixcmp(arg, "-n")) {
1005                revs->max_count = atoi(arg + 2);
1006        } else if (!prefixcmp(arg, "--max-age=")) {
1007                revs->max_age = atoi(arg + 10);
1008        } else if (!prefixcmp(arg, "--since=")) {
1009                revs->max_age = approxidate(arg + 8);
1010        } else if (!prefixcmp(arg, "--after=")) {
1011                revs->max_age = approxidate(arg + 8);
1012        } else if (!prefixcmp(arg, "--min-age=")) {
1013                revs->min_age = atoi(arg + 10);
1014        } else if (!prefixcmp(arg, "--before=")) {
1015                revs->min_age = approxidate(arg + 9);
1016        } else if (!prefixcmp(arg, "--until=")) {
1017                revs->min_age = approxidate(arg + 8);
1018        } else if (!strcmp(arg, "--first-parent")) {
1019                revs->first_parent_only = 1;
1020        } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
1021                init_reflog_walk(&revs->reflog_info);
1022        } else if (!strcmp(arg, "--default")) {
1023                if (argc <= 1)
1024                        return error("bad --default argument");
1025                revs->def = argv[1];
1026                return 2;
1027        } else if (!strcmp(arg, "--merge")) {
1028                revs->show_merge = 1;
1029        } else if (!strcmp(arg, "--topo-order")) {
1030                revs->lifo = 1;
1031                revs->topo_order = 1;
1032        } else if (!strcmp(arg, "--date-order")) {
1033                revs->lifo = 0;
1034                revs->topo_order = 1;
1035        } else if (!prefixcmp(arg, "--early-output")) {
1036                int count = 100;
1037                switch (arg[14]) {
1038                case '=':
1039                        count = atoi(arg+15);
1040                        /* Fallthrough */
1041                case 0:
1042                        revs->topo_order = 1;
1043                       revs->early_output = count;
1044                }
1045        } else if (!strcmp(arg, "--parents")) {
1046                revs->rewrite_parents = 1;
1047                revs->print_parents = 1;
1048        } else if (!strcmp(arg, "--dense")) {
1049                revs->dense = 1;
1050        } else if (!strcmp(arg, "--sparse")) {
1051                revs->dense = 0;
1052        } else if (!strcmp(arg, "--show-all")) {
1053                revs->show_all = 1;
1054        } else if (!strcmp(arg, "--remove-empty")) {
1055                revs->remove_empty_trees = 1;
1056        } else if (!strcmp(arg, "--no-merges")) {
1057                revs->no_merges = 1;
1058        } else if (!strcmp(arg, "--boundary")) {
1059                revs->boundary = 1;
1060        } else if (!strcmp(arg, "--left-right")) {
1061                revs->left_right = 1;
1062        } else if (!strcmp(arg, "--cherry-pick")) {
1063                revs->cherry_pick = 1;
1064                revs->limited = 1;
1065        } else if (!strcmp(arg, "--objects")) {
1066                revs->tag_objects = 1;
1067                revs->tree_objects = 1;
1068                revs->blob_objects = 1;
1069        } else if (!strcmp(arg, "--objects-edge")) {
1070                revs->tag_objects = 1;
1071                revs->tree_objects = 1;
1072                revs->blob_objects = 1;
1073                revs->edge_hint = 1;
1074        } else if (!strcmp(arg, "--unpacked")) {
1075                revs->unpacked = 1;
1076                free(revs->ignore_packed);
1077                revs->ignore_packed = NULL;
1078                revs->num_ignore_packed = 0;
1079        } else if (!prefixcmp(arg, "--unpacked=")) {
1080                revs->unpacked = 1;
1081                add_ignore_packed(revs, arg+11);
1082        } else if (!strcmp(arg, "-r")) {
1083                revs->diff = 1;
1084                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1085        } else if (!strcmp(arg, "-t")) {
1086                revs->diff = 1;
1087                DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
1088                DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
1089        } else if (!strcmp(arg, "-m")) {
1090                revs->ignore_merges = 0;
1091        } else if (!strcmp(arg, "-c")) {
1092                revs->diff = 1;
1093                revs->dense_combined_merges = 0;
1094                revs->combine_merges = 1;
1095        } else if (!strcmp(arg, "--cc")) {
1096                revs->diff = 1;
1097                revs->dense_combined_merges = 1;
1098                revs->combine_merges = 1;
1099        } else if (!strcmp(arg, "-v")) {
1100                revs->verbose_header = 1;
1101        } else if (!strcmp(arg, "--pretty")) {
1102                revs->verbose_header = 1;
1103                get_commit_format(arg+8, revs);
1104        } else if (!prefixcmp(arg, "--pretty=")) {
1105                revs->verbose_header = 1;
1106                get_commit_format(arg+9, revs);
1107        } else if (!strcmp(arg, "--graph")) {
1108                revs->topo_order = 1;
1109                revs->rewrite_parents = 1;
1110                revs->graph = graph_init(revs);
1111        } else if (!strcmp(arg, "--root")) {
1112                revs->show_root_diff = 1;
1113        } else if (!strcmp(arg, "--no-commit-id")) {
1114                revs->no_commit_id = 1;
1115        } else if (!strcmp(arg, "--always")) {
1116                revs->always_show_header = 1;
1117        } else if (!strcmp(arg, "--no-abbrev")) {
1118                revs->abbrev = 0;
1119        } else if (!strcmp(arg, "--abbrev")) {
1120                revs->abbrev = DEFAULT_ABBREV;
1121        } else if (!prefixcmp(arg, "--abbrev=")) {
1122                revs->abbrev = strtoul(arg + 9, NULL, 10);
1123                if (revs->abbrev < MINIMUM_ABBREV)
1124                        revs->abbrev = MINIMUM_ABBREV;
1125                else if (revs->abbrev > 40)
1126                        revs->abbrev = 40;
1127        } else if (!strcmp(arg, "--abbrev-commit")) {
1128                revs->abbrev_commit = 1;
1129        } else if (!strcmp(arg, "--full-diff")) {
1130                revs->diff = 1;
1131                revs->full_diff = 1;
1132        } else if (!strcmp(arg, "--full-history")) {
1133                revs->simplify_history = 0;
1134        } else if (!strcmp(arg, "--relative-date")) {
1135                revs->date_mode = DATE_RELATIVE;
1136        } else if (!strncmp(arg, "--date=", 7)) {
1137                revs->date_mode = parse_date_format(arg + 7);
1138        } else if (!strcmp(arg, "--log-size")) {
1139                revs->show_log_size = 1;
1140        }
1141        /*
1142         * Grepping the commit log
1143         */
1144        else if (!prefixcmp(arg, "--author=")) {
1145                add_header_grep(revs, "author", arg+9);
1146        } else if (!prefixcmp(arg, "--committer=")) {
1147                add_header_grep(revs, "committer", arg+12);
1148        } else if (!prefixcmp(arg, "--grep=")) {
1149                add_message_grep(revs, arg+7);
1150        } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
1151                if (revs->grep_filter)
1152                        revs->grep_filter->regflags |= REG_EXTENDED;
1153        } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
1154                if (revs->grep_filter)
1155                        revs->grep_filter->regflags |= REG_ICASE;
1156        } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
1157                if (revs->grep_filter)
1158                        revs->grep_filter->fixed = 1;
1159        } else if (!strcmp(arg, "--all-match")) {
1160                if (revs->grep_filter)
1161                        revs->grep_filter->all_match = 1;
1162        } else if (!prefixcmp(arg, "--encoding=")) {
1163                arg += 11;
1164                if (strcmp(arg, "none"))
1165                        git_log_output_encoding = xstrdup(arg);
1166                else
1167                        git_log_output_encoding = "";
1168        } else if (!strcmp(arg, "--reverse")) {
1169                revs->reverse ^= 1;
1170        } else if (!strcmp(arg, "--children")) {
1171                revs->children.name = "children";
1172                revs->limited = 1;
1173        } else {
1174                int opts = diff_opt_parse(&revs->diffopt, argv, argc);
1175                if (!opts)
1176                        unkv[(*unkc)++] = arg;
1177                return opts;
1178        }
1179
1180        return 1;
1181}
1182
1183void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
1184                        const struct option *options,
1185                        const char * const usagestr[])
1186{
1187        int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
1188                                    &ctx->cpidx, ctx->out);
1189        if (n <= 0) {
1190                error("unknown option `%s'", ctx->argv[0]);
1191                usage_with_options(usagestr, options);
1192        }
1193        ctx->argv += n;
1194        ctx->argc -= n;
1195}
1196
1197/*
1198 * Parse revision information, filling in the "rev_info" structure,
1199 * and removing the used arguments from the argument list.
1200 *
1201 * Returns the number of arguments left that weren't recognized
1202 * (which are also moved to the head of the argument list)
1203 */
1204int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
1205{
1206        int i, flags, left, seen_dashdash;
1207
1208        /* First, search for "--" */
1209        seen_dashdash = 0;
1210        for (i = 1; i < argc; i++) {
1211                const char *arg = argv[i];
1212                if (strcmp(arg, "--"))
1213                        continue;
1214                argv[i] = NULL;
1215                argc = i;
1216                if (argv[i + 1])
1217                        revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
1218                seen_dashdash = 1;
1219                break;
1220        }
1221
1222        /* Second, deal with arguments and options */
1223        flags = 0;
1224        for (left = i = 1; i < argc; i++) {
1225                const char *arg = argv[i];
1226                if (*arg == '-') {
1227                        int opts;
1228
1229                        if (!strcmp(arg, "--all")) {
1230                                handle_refs(revs, flags, for_each_ref);
1231                                continue;
1232                        }
1233                        if (!strcmp(arg, "--branches")) {
1234                                handle_refs(revs, flags, for_each_branch_ref);
1235                                continue;
1236                        }
1237                        if (!strcmp(arg, "--tags")) {
1238                                handle_refs(revs, flags, for_each_tag_ref);
1239                                continue;
1240                        }
1241                        if (!strcmp(arg, "--remotes")) {
1242                                handle_refs(revs, flags, for_each_remote_ref);
1243                                continue;
1244                        }
1245                        if (!strcmp(arg, "--reflog")) {
1246                                handle_reflog(revs, flags);
1247                                continue;
1248                        }
1249                        if (!strcmp(arg, "--not")) {
1250                                flags ^= UNINTERESTING;
1251                                continue;
1252                        }
1253                        if (!strcmp(arg, "--no-walk")) {
1254                                revs->no_walk = 1;
1255                                continue;
1256                        }
1257                        if (!strcmp(arg, "--do-walk")) {
1258                                revs->no_walk = 0;
1259                                continue;
1260                        }
1261
1262                        opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
1263                        if (opts > 0) {
1264                                i += opts - 1;
1265                                continue;
1266                        }
1267                        if (opts < 0)
1268                                exit(128);
1269                        continue;
1270                }
1271
1272                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1273                        int j;
1274                        if (seen_dashdash || *arg == '^')
1275                                die("bad revision '%s'", arg);
1276
1277                        /* If we didn't have a "--":
1278                         * (1) all filenames must exist;
1279                         * (2) all rev-args must not be interpretable
1280                         *     as a valid filename.
1281                         * but the latter we have checked in the main loop.
1282                         */
1283                        for (j = i; j < argc; j++)
1284                                verify_filename(revs->prefix, argv[j]);
1285
1286                        revs->prune_data = get_pathspec(revs->prefix,
1287                                                        argv + i);
1288                        break;
1289                }
1290        }
1291
1292        if (revs->def == NULL)
1293                revs->def = def;
1294        if (revs->show_merge)
1295                prepare_show_merge(revs);
1296        if (revs->def && !revs->pending.nr) {
1297                unsigned char sha1[20];
1298                struct object *object;
1299                unsigned mode;
1300                if (get_sha1_with_mode(revs->def, sha1, &mode))
1301                        die("bad default revision '%s'", revs->def);
1302                object = get_reference(revs, revs->def, sha1, 0);
1303                add_pending_object_with_mode(revs, object, revs->def, mode);
1304        }
1305
1306        /* Did the user ask for any diff output? Run the diff! */
1307        if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
1308                revs->diff = 1;
1309
1310        /* Pickaxe, diff-filter and rename following need diffs */
1311        if (revs->diffopt.pickaxe ||
1312            revs->diffopt.filter ||
1313            DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
1314                revs->diff = 1;
1315
1316        if (revs->topo_order)
1317                revs->limited = 1;
1318
1319        if (revs->prune_data) {
1320                diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1321                /* Can't prune commits with rename following: the paths change.. */
1322                if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
1323                        revs->prune = 1;
1324                if (!revs->full_diff)
1325                        diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1326        }
1327        if (revs->combine_merges) {
1328                revs->ignore_merges = 0;
1329                if (revs->dense_combined_merges && !revs->diffopt.output_format)
1330                        revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1331        }
1332        revs->diffopt.abbrev = revs->abbrev;
1333        if (diff_setup_done(&revs->diffopt) < 0)
1334                die("diff_setup_done failed");
1335
1336        if (revs->grep_filter) {
1337                compile_grep_patterns(revs->grep_filter);
1338        }
1339
1340        if (revs->reverse && revs->reflog_info)
1341                die("cannot combine --reverse with --walk-reflogs");
1342        if (revs->rewrite_parents && revs->children.name)
1343                die("cannot combine --parents and --children");
1344
1345        /*
1346         * Limitations on the graph functionality
1347         */
1348        if (revs->reverse && revs->graph)
1349                die("cannot combine --reverse with --graph");
1350
1351        if (revs->reflog_info && revs->graph)
1352                die("cannot combine --walk-reflogs with --graph");
1353
1354        return left;
1355}
1356
1357static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
1358{
1359        struct commit_list *l = xcalloc(1, sizeof(*l));
1360
1361        l->item = child;
1362        l->next = add_decoration(&revs->children, &parent->object, l);
1363}
1364
1365static void set_children(struct rev_info *revs)
1366{
1367        struct commit_list *l;
1368        for (l = revs->commits; l; l = l->next) {
1369                struct commit *commit = l->item;
1370                struct commit_list *p;
1371
1372                for (p = commit->parents; p; p = p->next)
1373                        add_child(revs, p->item, commit);
1374        }
1375}
1376
1377int prepare_revision_walk(struct rev_info *revs)
1378{
1379        int nr = revs->pending.nr;
1380        struct object_array_entry *e, *list;
1381
1382        e = list = revs->pending.objects;
1383        revs->pending.nr = 0;
1384        revs->pending.alloc = 0;
1385        revs->pending.objects = NULL;
1386        while (--nr >= 0) {
1387                struct commit *commit = handle_commit(revs, e->item, e->name);
1388                if (commit) {
1389                        if (!(commit->object.flags & SEEN)) {
1390                                commit->object.flags |= SEEN;
1391                                insert_by_date(commit, &revs->commits);
1392                        }
1393                }
1394                e++;
1395        }
1396        free(list);
1397
1398        if (revs->no_walk)
1399                return 0;
1400        if (revs->limited)
1401                if (limit_list(revs) < 0)
1402                        return -1;
1403        if (revs->topo_order)
1404                sort_in_topological_order(&revs->commits, revs->lifo);
1405        if (revs->children.name)
1406                set_children(revs);
1407        return 0;
1408}
1409
1410enum rewrite_result {
1411        rewrite_one_ok,
1412        rewrite_one_noparents,
1413        rewrite_one_error,
1414};
1415
1416static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
1417{
1418        for (;;) {
1419                struct commit *p = *pp;
1420                if (!revs->limited)
1421                        if (add_parents_to_list(revs, p, &revs->commits) < 0)
1422                                return rewrite_one_error;
1423                if (p->parents && p->parents->next)
1424                        return rewrite_one_ok;
1425                if (p->object.flags & UNINTERESTING)
1426                        return rewrite_one_ok;
1427                if (!(p->object.flags & TREESAME))
1428                        return rewrite_one_ok;
1429                if (!p->parents)
1430                        return rewrite_one_noparents;
1431                *pp = p->parents->item;
1432        }
1433}
1434
1435static void remove_duplicate_parents(struct commit *commit)
1436{
1437        struct commit_list **pp, *p;
1438
1439        /* Examine existing parents while marking ones we have seen... */
1440        pp = &commit->parents;
1441        while ((p = *pp) != NULL) {
1442                struct commit *parent = p->item;
1443                if (parent->object.flags & TMP_MARK) {
1444                        *pp = p->next;
1445                        continue;
1446                }
1447                parent->object.flags |= TMP_MARK;
1448                pp = &p->next;
1449        }
1450        /* ... and clear the temporary mark */
1451        for (p = commit->parents; p; p = p->next)
1452                p->item->object.flags &= ~TMP_MARK;
1453}
1454
1455static int rewrite_parents(struct rev_info *revs, struct commit *commit)
1456{
1457        struct commit_list **pp = &commit->parents;
1458        while (*pp) {
1459                struct commit_list *parent = *pp;
1460                switch (rewrite_one(revs, &parent->item)) {
1461                case rewrite_one_ok:
1462                        break;
1463                case rewrite_one_noparents:
1464                        *pp = parent->next;
1465                        continue;
1466                case rewrite_one_error:
1467                        return -1;
1468                }
1469                pp = &parent->next;
1470        }
1471        remove_duplicate_parents(commit);
1472        return 0;
1473}
1474
1475static int commit_match(struct commit *commit, struct rev_info *opt)
1476{
1477        if (!opt->grep_filter)
1478                return 1;
1479        return grep_buffer(opt->grep_filter,
1480                           NULL, /* we say nothing, not even filename */
1481                           commit->buffer, strlen(commit->buffer));
1482}
1483
1484static inline int want_ancestry(struct rev_info *revs)
1485{
1486        return (revs->rewrite_parents || revs->children.name);
1487}
1488
1489enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
1490{
1491        if (commit->object.flags & SHOWN)
1492                return commit_ignore;
1493        if (revs->unpacked && has_sha1_pack(commit->object.sha1, revs->ignore_packed))
1494                return commit_ignore;
1495        if (revs->show_all)
1496                return commit_show;
1497        if (commit->object.flags & UNINTERESTING)
1498                return commit_ignore;
1499        if (revs->min_age != -1 && (commit->date > revs->min_age))
1500                return commit_ignore;
1501        if (revs->no_merges && commit->parents && commit->parents->next)
1502                return commit_ignore;
1503        if (!commit_match(commit, revs))
1504                return commit_ignore;
1505        if (revs->prune && revs->dense) {
1506                /* Commit without changes? */
1507                if (commit->object.flags & TREESAME) {
1508                        /* drop merges unless we want parenthood */
1509                        if (!want_ancestry(revs))
1510                                return commit_ignore;
1511                        /* non-merge - always ignore it */
1512                        if (!commit->parents || !commit->parents->next)
1513                                return commit_ignore;
1514                }
1515                if (want_ancestry(revs) && rewrite_parents(revs, commit) < 0)
1516                        return commit_error;
1517        }
1518        return commit_show;
1519}
1520
1521static struct commit *get_revision_1(struct rev_info *revs)
1522{
1523        if (!revs->commits)
1524                return NULL;
1525
1526        do {
1527                struct commit_list *entry = revs->commits;
1528                struct commit *commit = entry->item;
1529
1530                revs->commits = entry->next;
1531                free(entry);
1532
1533                if (revs->reflog_info)
1534                        fake_reflog_parent(revs->reflog_info, commit);
1535
1536                /*
1537                 * If we haven't done the list limiting, we need to look at
1538                 * the parents here. We also need to do the date-based limiting
1539                 * that we'd otherwise have done in limit_list().
1540                 */
1541                if (!revs->limited) {
1542                        if (revs->max_age != -1 &&
1543                            (commit->date < revs->max_age))
1544                                continue;
1545                        if (add_parents_to_list(revs, commit, &revs->commits) < 0)
1546                                return NULL;
1547                }
1548
1549                switch (simplify_commit(revs, commit)) {
1550                case commit_ignore:
1551                        continue;
1552                case commit_error:
1553                        return NULL;
1554                default:
1555                        return commit;
1556                }
1557        } while (revs->commits);
1558        return NULL;
1559}
1560
1561static void gc_boundary(struct object_array *array)
1562{
1563        unsigned nr = array->nr;
1564        unsigned alloc = array->alloc;
1565        struct object_array_entry *objects = array->objects;
1566
1567        if (alloc <= nr) {
1568                unsigned i, j;
1569                for (i = j = 0; i < nr; i++) {
1570                        if (objects[i].item->flags & SHOWN)
1571                                continue;
1572                        if (i != j)
1573                                objects[j] = objects[i];
1574                        j++;
1575                }
1576                for (i = j; i < nr; i++)
1577                        objects[i].item = NULL;
1578                array->nr = j;
1579        }
1580}
1581
1582static void create_boundary_commit_list(struct rev_info *revs)
1583{
1584        unsigned i;
1585        struct commit *c;
1586        struct object_array *array = &revs->boundary_commits;
1587        struct object_array_entry *objects = array->objects;
1588
1589        /*
1590         * If revs->commits is non-NULL at this point, an error occurred in
1591         * get_revision_1().  Ignore the error and continue printing the
1592         * boundary commits anyway.  (This is what the code has always
1593         * done.)
1594         */
1595        if (revs->commits) {
1596                free_commit_list(revs->commits);
1597                revs->commits = NULL;
1598        }
1599
1600        /*
1601         * Put all of the actual boundary commits from revs->boundary_commits
1602         * into revs->commits
1603         */
1604        for (i = 0; i < array->nr; i++) {
1605                c = (struct commit *)(objects[i].item);
1606                if (!c)
1607                        continue;
1608                if (!(c->object.flags & CHILD_SHOWN))
1609                        continue;
1610                if (c->object.flags & (SHOWN | BOUNDARY))
1611                        continue;
1612                c->object.flags |= BOUNDARY;
1613                commit_list_insert(c, &revs->commits);
1614        }
1615
1616        /*
1617         * If revs->topo_order is set, sort the boundary commits
1618         * in topological order
1619         */
1620        sort_in_topological_order(&revs->commits, revs->lifo);
1621}
1622
1623static struct commit *get_revision_internal(struct rev_info *revs)
1624{
1625        struct commit *c = NULL;
1626        struct commit_list *l;
1627
1628        if (revs->boundary == 2) {
1629                /*
1630                 * All of the normal commits have already been returned,
1631                 * and we are now returning boundary commits.
1632                 * create_boundary_commit_list() has populated
1633                 * revs->commits with the remaining commits to return.
1634                 */
1635                c = pop_commit(&revs->commits);
1636                if (c)
1637                        c->object.flags |= SHOWN;
1638                return c;
1639        }
1640
1641        if (revs->reverse) {
1642                int limit = -1;
1643
1644                if (0 <= revs->max_count) {
1645                        limit = revs->max_count;
1646                        if (0 < revs->skip_count)
1647                                limit += revs->skip_count;
1648                }
1649                l = NULL;
1650                while ((c = get_revision_1(revs))) {
1651                        commit_list_insert(c, &l);
1652                        if ((0 < limit) && !--limit)
1653                                break;
1654                }
1655                revs->commits = l;
1656                revs->reverse = 0;
1657                revs->max_count = -1;
1658                c = NULL;
1659        }
1660
1661        /*
1662         * Now pick up what they want to give us
1663         */
1664        c = get_revision_1(revs);
1665        if (c) {
1666                while (0 < revs->skip_count) {
1667                        revs->skip_count--;
1668                        c = get_revision_1(revs);
1669                        if (!c)
1670                                break;
1671                }
1672        }
1673
1674        /*
1675         * Check the max_count.
1676         */
1677        switch (revs->max_count) {
1678        case -1:
1679                break;
1680        case 0:
1681                c = NULL;
1682                break;
1683        default:
1684                revs->max_count--;
1685        }
1686
1687        if (c)
1688                c->object.flags |= SHOWN;
1689
1690        if (!revs->boundary) {
1691                return c;
1692        }
1693
1694        if (!c) {
1695                /*
1696                 * get_revision_1() runs out the commits, and
1697                 * we are done computing the boundaries.
1698                 * switch to boundary commits output mode.
1699                 */
1700                revs->boundary = 2;
1701
1702                /*
1703                 * Update revs->commits to contain the list of
1704                 * boundary commits.
1705                 */
1706                create_boundary_commit_list(revs);
1707
1708                return get_revision_internal(revs);
1709        }
1710
1711        /*
1712         * boundary commits are the commits that are parents of the
1713         * ones we got from get_revision_1() but they themselves are
1714         * not returned from get_revision_1().  Before returning
1715         * 'c', we need to mark its parents that they could be boundaries.
1716         */
1717
1718        for (l = c->parents; l; l = l->next) {
1719                struct object *p;
1720                p = &(l->item->object);
1721                if (p->flags & (CHILD_SHOWN | SHOWN))
1722                        continue;
1723                p->flags |= CHILD_SHOWN;
1724                gc_boundary(&revs->boundary_commits);
1725                add_object_array(p, NULL, &revs->boundary_commits);
1726        }
1727
1728        return c;
1729}
1730
1731struct commit *get_revision(struct rev_info *revs)
1732{
1733        struct commit *c = get_revision_internal(revs);
1734        if (c && revs->graph)
1735                graph_update(revs->graph, c);
1736        return c;
1737}