Andrew's git / gitweb.git / revision.c
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revision.con commit git-log --cherry-pick A...B (d7a17ca)
   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 "grep.h"
  10#include "reflog-walk.h"
  11#include "patch-ids.h"
  12
  13static char *path_name(struct name_path *path, const char *name)
  14{
  15        struct name_path *p;
  16        char *n, *m;
  17        int nlen = strlen(name);
  18        int len = nlen + 1;
  19
  20        for (p = path; p; p = p->up) {
  21                if (p->elem_len)
  22                        len += p->elem_len + 1;
  23        }
  24        n = xmalloc(len);
  25        m = n + len - (nlen + 1);
  26        strcpy(m, name);
  27        for (p = path; p; p = p->up) {
  28                if (p->elem_len) {
  29                        m -= p->elem_len + 1;
  30                        memcpy(m, p->elem, p->elem_len);
  31                        m[p->elem_len] = '/';
  32                }
  33        }
  34        return n;
  35}
  36
  37void add_object(struct object *obj,
  38                struct object_array *p,
  39                struct name_path *path,
  40                const char *name)
  41{
  42        add_object_array(obj, path_name(path, name), p);
  43}
  44
  45static void mark_blob_uninteresting(struct blob *blob)
  46{
  47        if (blob->object.flags & UNINTERESTING)
  48                return;
  49        blob->object.flags |= UNINTERESTING;
  50}
  51
  52void mark_tree_uninteresting(struct tree *tree)
  53{
  54        struct tree_desc desc;
  55        struct name_entry entry;
  56        struct object *obj = &tree->object;
  57
  58        if (obj->flags & UNINTERESTING)
  59                return;
  60        obj->flags |= UNINTERESTING;
  61        if (!has_sha1_file(obj->sha1))
  62                return;
  63        if (parse_tree(tree) < 0)
  64                die("bad tree %s", sha1_to_hex(obj->sha1));
  65
  66        init_tree_desc(&desc, tree->buffer, tree->size);
  67        while (tree_entry(&desc, &entry)) {
  68                if (S_ISDIR(entry.mode))
  69                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  70                else
  71                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  72        }
  73
  74        /*
  75         * We don't care about the tree any more
  76         * after it has been marked uninteresting.
  77         */
  78        free(tree->buffer);
  79        tree->buffer = NULL;
  80}
  81
  82void mark_parents_uninteresting(struct commit *commit)
  83{
  84        struct commit_list *parents = commit->parents;
  85
  86        while (parents) {
  87                struct commit *commit = parents->item;
  88                if (!(commit->object.flags & UNINTERESTING)) {
  89                        commit->object.flags |= UNINTERESTING;
  90
  91                        /*
  92                         * Normally we haven't parsed the parent
  93                         * yet, so we won't have a parent of a parent
  94                         * here. However, it may turn out that we've
  95                         * reached this commit some other way (where it
  96                         * wasn't uninteresting), in which case we need
  97                         * to mark its parents recursively too..
  98                         */
  99                        if (commit->parents)
 100                                mark_parents_uninteresting(commit);
 101                }
 102
 103                /*
 104                 * A missing commit is ok iff its parent is marked
 105                 * uninteresting.
 106                 *
 107                 * We just mark such a thing parsed, so that when
 108                 * it is popped next time around, we won't be trying
 109                 * to parse it and get an error.
 110                 */
 111                if (!has_sha1_file(commit->object.sha1))
 112                        commit->object.parsed = 1;
 113                parents = parents->next;
 114        }
 115}
 116
 117void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 118{
 119        if (revs->no_walk && (obj->flags & UNINTERESTING))
 120                die("object ranges do not make sense when not walking revisions");
 121        add_object_array(obj, name, &revs->pending);
 122        if (revs->reflog_info && obj->type == OBJ_COMMIT)
 123                add_reflog_for_walk(revs->reflog_info,
 124                                (struct commit *)obj, name);
 125}
 126
 127static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 128{
 129        struct object *object;
 130
 131        object = parse_object(sha1);
 132        if (!object)
 133                die("bad object %s", name);
 134        object->flags |= flags;
 135        return object;
 136}
 137
 138static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 139{
 140        unsigned long flags = object->flags;
 141
 142        /*
 143         * Tag object? Look what it points to..
 144         */
 145        while (object->type == OBJ_TAG) {
 146                struct tag *tag = (struct tag *) object;
 147                if (revs->tag_objects && !(flags & UNINTERESTING))
 148                        add_pending_object(revs, object, tag->tag);
 149                object = parse_object(tag->tagged->sha1);
 150                if (!object)
 151                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 152        }
 153
 154        /*
 155         * Commit object? Just return it, we'll do all the complex
 156         * reachability crud.
 157         */
 158        if (object->type == OBJ_COMMIT) {
 159                struct commit *commit = (struct commit *)object;
 160                if (parse_commit(commit) < 0)
 161                        die("unable to parse commit %s", name);
 162                if (flags & UNINTERESTING) {
 163                        commit->object.flags |= UNINTERESTING;
 164                        mark_parents_uninteresting(commit);
 165                        revs->limited = 1;
 166                }
 167                return commit;
 168        }
 169
 170        /*
 171         * Tree object? Either mark it uniniteresting, or add it
 172         * to the list of objects to look at later..
 173         */
 174        if (object->type == OBJ_TREE) {
 175                struct tree *tree = (struct tree *)object;
 176                if (!revs->tree_objects)
 177                        return NULL;
 178                if (flags & UNINTERESTING) {
 179                        mark_tree_uninteresting(tree);
 180                        return NULL;
 181                }
 182                add_pending_object(revs, object, "");
 183                return NULL;
 184        }
 185
 186        /*
 187         * Blob object? You know the drill by now..
 188         */
 189        if (object->type == OBJ_BLOB) {
 190                struct blob *blob = (struct blob *)object;
 191                if (!revs->blob_objects)
 192                        return NULL;
 193                if (flags & UNINTERESTING) {
 194                        mark_blob_uninteresting(blob);
 195                        return NULL;
 196                }
 197                add_pending_object(revs, object, "");
 198                return NULL;
 199        }
 200        die("%s is unknown object", name);
 201}
 202
 203static int everybody_uninteresting(struct commit_list *orig)
 204{
 205        struct commit_list *list = orig;
 206        while (list) {
 207                struct commit *commit = list->item;
 208                list = list->next;
 209                if (commit->object.flags & UNINTERESTING)
 210                        continue;
 211                return 0;
 212        }
 213        return 1;
 214}
 215
 216/*
 217 * The goal is to get REV_TREE_NEW as the result only if the
 218 * diff consists of all '+' (and no other changes), and
 219 * REV_TREE_DIFFERENT otherwise (of course if the trees are
 220 * the same we want REV_TREE_SAME).  That means that once we
 221 * get to REV_TREE_DIFFERENT, we do not have to look any further.
 222 */
 223static int tree_difference = REV_TREE_SAME;
 224
 225static void file_add_remove(struct diff_options *options,
 226                    int addremove, unsigned mode,
 227                    const unsigned char *sha1,
 228                    const char *base, const char *path)
 229{
 230        int diff = REV_TREE_DIFFERENT;
 231
 232        /*
 233         * Is it an add of a new file? It means that the old tree
 234         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 235         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 236         * (and if it already was "REV_TREE_NEW", we'll keep it
 237         * "REV_TREE_NEW" of course).
 238         */
 239        if (addremove == '+') {
 240                diff = tree_difference;
 241                if (diff != REV_TREE_SAME)
 242                        return;
 243                diff = REV_TREE_NEW;
 244        }
 245        tree_difference = diff;
 246        if (tree_difference == REV_TREE_DIFFERENT)
 247                options->has_changes = 1;
 248}
 249
 250static void file_change(struct diff_options *options,
 251                 unsigned old_mode, unsigned new_mode,
 252                 const unsigned char *old_sha1,
 253                 const unsigned char *new_sha1,
 254                 const char *base, const char *path)
 255{
 256        tree_difference = REV_TREE_DIFFERENT;
 257        options->has_changes = 1;
 258}
 259
 260int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 261{
 262        if (!t1)
 263                return REV_TREE_NEW;
 264        if (!t2)
 265                return REV_TREE_DIFFERENT;
 266        tree_difference = REV_TREE_SAME;
 267        revs->pruning.has_changes = 0;
 268        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 269                           &revs->pruning) < 0)
 270                return REV_TREE_DIFFERENT;
 271        return tree_difference;
 272}
 273
 274int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 275{
 276        int retval;
 277        void *tree;
 278        unsigned long size;
 279        struct tree_desc empty, real;
 280
 281        if (!t1)
 282                return 0;
 283
 284        tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
 285        if (!tree)
 286                return 0;
 287        init_tree_desc(&real, tree, size);
 288        init_tree_desc(&empty, "", 0);
 289
 290        tree_difference = REV_TREE_SAME;
 291        revs->pruning.has_changes = 0;
 292        retval = diff_tree(&empty, &real, "", &revs->pruning);
 293        free(tree);
 294
 295        return retval >= 0 && (tree_difference == REV_TREE_SAME);
 296}
 297
 298static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 299{
 300        struct commit_list **pp, *parent;
 301        int tree_changed = 0, tree_same = 0;
 302
 303        if (!commit->tree)
 304                return;
 305
 306        if (!commit->parents) {
 307                if (!rev_same_tree_as_empty(revs, commit->tree))
 308                        commit->object.flags |= TREECHANGE;
 309                return;
 310        }
 311
 312        pp = &commit->parents;
 313        while ((parent = *pp) != NULL) {
 314                struct commit *p = parent->item;
 315
 316                parse_commit(p);
 317                switch (rev_compare_tree(revs, p->tree, commit->tree)) {
 318                case REV_TREE_SAME:
 319                        tree_same = 1;
 320                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 321                                /* Even if a merge with an uninteresting
 322                                 * side branch brought the entire change
 323                                 * we are interested in, we do not want
 324                                 * to lose the other branches of this
 325                                 * merge, so we just keep going.
 326                                 */
 327                                pp = &parent->next;
 328                                continue;
 329                        }
 330                        parent->next = NULL;
 331                        commit->parents = parent;
 332                        return;
 333
 334                case REV_TREE_NEW:
 335                        if (revs->remove_empty_trees &&
 336                            rev_same_tree_as_empty(revs, p->tree)) {
 337                                /* We are adding all the specified
 338                                 * paths from this parent, so the
 339                                 * history beyond this parent is not
 340                                 * interesting.  Remove its parents
 341                                 * (they are grandparents for us).
 342                                 * IOW, we pretend this parent is a
 343                                 * "root" commit.
 344                                 */
 345                                parse_commit(p);
 346                                p->parents = NULL;
 347                        }
 348                /* fallthrough */
 349                case REV_TREE_DIFFERENT:
 350                        tree_changed = 1;
 351                        pp = &parent->next;
 352                        continue;
 353                }
 354                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 355        }
 356        if (tree_changed && !tree_same)
 357                commit->object.flags |= TREECHANGE;
 358}
 359
 360static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 361{
 362        struct commit_list *parent = commit->parents;
 363        unsigned left_flag;
 364        int add, rest;
 365
 366        if (commit->object.flags & ADDED)
 367                return;
 368        commit->object.flags |= ADDED;
 369
 370        /*
 371         * If the commit is uninteresting, don't try to
 372         * prune parents - we want the maximal uninteresting
 373         * set.
 374         *
 375         * Normally we haven't parsed the parent
 376         * yet, so we won't have a parent of a parent
 377         * here. However, it may turn out that we've
 378         * reached this commit some other way (where it
 379         * wasn't uninteresting), in which case we need
 380         * to mark its parents recursively too..
 381         */
 382        if (commit->object.flags & UNINTERESTING) {
 383                while (parent) {
 384                        struct commit *p = parent->item;
 385                        parent = parent->next;
 386                        parse_commit(p);
 387                        p->object.flags |= UNINTERESTING;
 388                        if (p->parents)
 389                                mark_parents_uninteresting(p);
 390                        if (p->object.flags & SEEN)
 391                                continue;
 392                        p->object.flags |= SEEN;
 393                        insert_by_date(p, list);
 394                }
 395                return;
 396        }
 397
 398        /*
 399         * Ok, the commit wasn't uninteresting. Try to
 400         * simplify the commit history and find the parent
 401         * that has no differences in the path set if one exists.
 402         */
 403        if (revs->prune_fn)
 404                revs->prune_fn(revs, commit);
 405
 406        if (revs->no_walk)
 407                return;
 408
 409        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 410
 411        rest = !revs->first_parent_only;
 412        for (parent = commit->parents, add = 1; parent; add = rest) {
 413                struct commit *p = parent->item;
 414
 415                parent = parent->next;
 416                parse_commit(p);
 417                p->object.flags |= left_flag;
 418                if (p->object.flags & SEEN)
 419                        continue;
 420                p->object.flags |= SEEN;
 421                if (add)
 422                        insert_by_date(p, list);
 423        }
 424}
 425
 426static void cherry_pick_list(struct commit_list *list)
 427{
 428        struct commit_list *p;
 429        int left_count = 0, right_count = 0;
 430        int left_first;
 431        struct patch_ids ids;
 432
 433        /* First count the commits on the left and on the right */
 434        for (p = list; p; p = p->next) {
 435                struct commit *commit = p->item;
 436                unsigned flags = commit->object.flags;
 437                if (flags & BOUNDARY)
 438                        ;
 439                else if (flags & SYMMETRIC_LEFT)
 440                        left_count++;
 441                else
 442                        right_count++;
 443        }
 444
 445        left_first = left_count < right_count;
 446        init_patch_ids(&ids);
 447
 448        /* Compute patch-ids for one side */
 449        for (p = list; p; p = p->next) {
 450                struct commit *commit = p->item;
 451                unsigned flags = commit->object.flags;
 452
 453                if (flags & BOUNDARY)
 454                        continue;
 455                /*
 456                 * If we have fewer left, left_first is set and we omit
 457                 * commits on the right branch in this loop.  If we have
 458                 * fewer right, we skip the left ones.
 459                 */
 460                if (left_first != !!(flags & SYMMETRIC_LEFT))
 461                        continue;
 462                commit->util = add_commit_patch_id(commit, &ids);
 463        }
 464
 465        /* Check the other side */
 466        for (p = list; p; p = p->next) {
 467                struct commit *commit = p->item;
 468                struct patch_id *id;
 469                unsigned flags = commit->object.flags;
 470
 471                if (flags & BOUNDARY)
 472                        continue;
 473                /*
 474                 * If we have fewer left, left_first is set and we omit
 475                 * commits on the left branch in this loop.
 476                 */
 477                if (left_first == !!(flags & SYMMETRIC_LEFT))
 478                        continue;
 479
 480                /*
 481                 * Have we seen the same patch id?
 482                 */
 483                id = has_commit_patch_id(commit, &ids);
 484                if (!id)
 485                        continue;
 486                id->seen = 1;
 487                commit->object.flags |= SHOWN;
 488        }
 489
 490        /* Now check the original side for seen ones */
 491        for (p = list; p; p = p->next) {
 492                struct commit *commit = p->item;
 493                struct patch_id *ent;
 494
 495                ent = commit->util;
 496                if (!ent)
 497                        continue;
 498                if (ent->seen)
 499                        commit->object.flags |= SHOWN;
 500                commit->util = NULL;
 501        }
 502
 503        free_patch_ids(&ids);
 504}
 505
 506static void limit_list(struct rev_info *revs)
 507{
 508        struct commit_list *list = revs->commits;
 509        struct commit_list *newlist = NULL;
 510        struct commit_list **p = &newlist;
 511
 512        while (list) {
 513                struct commit_list *entry = list;
 514                struct commit *commit = list->item;
 515                struct object *obj = &commit->object;
 516
 517                list = list->next;
 518                free(entry);
 519
 520                if (revs->max_age != -1 && (commit->date < revs->max_age))
 521                        obj->flags |= UNINTERESTING;
 522                add_parents_to_list(revs, commit, &list);
 523                if (obj->flags & UNINTERESTING) {
 524                        mark_parents_uninteresting(commit);
 525                        if (everybody_uninteresting(list))
 526                                break;
 527                        continue;
 528                }
 529                if (revs->min_age != -1 && (commit->date > revs->min_age))
 530                        continue;
 531                p = &commit_list_insert(commit, p)->next;
 532        }
 533        if (revs->cherry_pick)
 534                cherry_pick_list(newlist);
 535
 536        revs->commits = newlist;
 537}
 538
 539struct all_refs_cb {
 540        int all_flags;
 541        int warned_bad_reflog;
 542        struct rev_info *all_revs;
 543        const char *name_for_errormsg;
 544};
 545
 546static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 547{
 548        struct all_refs_cb *cb = cb_data;
 549        struct object *object = get_reference(cb->all_revs, path, sha1,
 550                                              cb->all_flags);
 551        add_pending_object(cb->all_revs, object, path);
 552        return 0;
 553}
 554
 555static void handle_all(struct rev_info *revs, unsigned flags)
 556{
 557        struct all_refs_cb cb;
 558        cb.all_revs = revs;
 559        cb.all_flags = flags;
 560        for_each_ref(handle_one_ref, &cb);
 561}
 562
 563static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 564{
 565        struct all_refs_cb *cb = cb_data;
 566        if (!is_null_sha1(sha1)) {
 567                struct object *o = parse_object(sha1);
 568                if (o) {
 569                        o->flags |= cb->all_flags;
 570                        add_pending_object(cb->all_revs, o, "");
 571                }
 572                else if (!cb->warned_bad_reflog) {
 573                        warning("reflog of '%s' references pruned commits",
 574                                cb->name_for_errormsg);
 575                        cb->warned_bad_reflog = 1;
 576                }
 577        }
 578}
 579
 580static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 581                const char *email, unsigned long timestamp, int tz,
 582                const char *message, void *cb_data)
 583{
 584        handle_one_reflog_commit(osha1, cb_data);
 585        handle_one_reflog_commit(nsha1, cb_data);
 586        return 0;
 587}
 588
 589static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 590{
 591        struct all_refs_cb *cb = cb_data;
 592        cb->warned_bad_reflog = 0;
 593        cb->name_for_errormsg = path;
 594        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
 595        return 0;
 596}
 597
 598static void handle_reflog(struct rev_info *revs, unsigned flags)
 599{
 600        struct all_refs_cb cb;
 601        cb.all_revs = revs;
 602        cb.all_flags = flags;
 603        for_each_reflog(handle_one_reflog, &cb);
 604}
 605
 606static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 607{
 608        unsigned char sha1[20];
 609        struct object *it;
 610        struct commit *commit;
 611        struct commit_list *parents;
 612
 613        if (*arg == '^') {
 614                flags ^= UNINTERESTING;
 615                arg++;
 616        }
 617        if (get_sha1(arg, sha1))
 618                return 0;
 619        while (1) {
 620                it = get_reference(revs, arg, sha1, 0);
 621                if (it->type != OBJ_TAG)
 622                        break;
 623                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 624        }
 625        if (it->type != OBJ_COMMIT)
 626                return 0;
 627        commit = (struct commit *)it;
 628        for (parents = commit->parents; parents; parents = parents->next) {
 629                it = &parents->item->object;
 630                it->flags |= flags;
 631                add_pending_object(revs, it, arg);
 632        }
 633        return 1;
 634}
 635
 636void init_revisions(struct rev_info *revs, const char *prefix)
 637{
 638        memset(revs, 0, sizeof(*revs));
 639
 640        revs->abbrev = DEFAULT_ABBREV;
 641        revs->ignore_merges = 1;
 642        revs->simplify_history = 1;
 643        revs->pruning.recursive = 1;
 644        revs->pruning.quiet = 1;
 645        revs->pruning.add_remove = file_add_remove;
 646        revs->pruning.change = file_change;
 647        revs->lifo = 1;
 648        revs->dense = 1;
 649        revs->prefix = prefix;
 650        revs->max_age = -1;
 651        revs->min_age = -1;
 652        revs->skip_count = -1;
 653        revs->max_count = -1;
 654
 655        revs->prune_fn = NULL;
 656        revs->prune_data = NULL;
 657
 658        revs->topo_setter = topo_sort_default_setter;
 659        revs->topo_getter = topo_sort_default_getter;
 660
 661        revs->commit_format = CMIT_FMT_DEFAULT;
 662
 663        diff_setup(&revs->diffopt);
 664}
 665
 666static void add_pending_commit_list(struct rev_info *revs,
 667                                    struct commit_list *commit_list,
 668                                    unsigned int flags)
 669{
 670        while (commit_list) {
 671                struct object *object = &commit_list->item->object;
 672                object->flags |= flags;
 673                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 674                commit_list = commit_list->next;
 675        }
 676}
 677
 678static void prepare_show_merge(struct rev_info *revs)
 679{
 680        struct commit_list *bases;
 681        struct commit *head, *other;
 682        unsigned char sha1[20];
 683        const char **prune = NULL;
 684        int i, prune_num = 1; /* counting terminating NULL */
 685
 686        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 687                die("--merge without HEAD?");
 688        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 689                die("--merge without MERGE_HEAD?");
 690        add_pending_object(revs, &head->object, "HEAD");
 691        add_pending_object(revs, &other->object, "MERGE_HEAD");
 692        bases = get_merge_bases(head, other, 1);
 693        while (bases) {
 694                struct commit *it = bases->item;
 695                struct commit_list *n = bases->next;
 696                free(bases);
 697                bases = n;
 698                it->object.flags |= UNINTERESTING;
 699                add_pending_object(revs, &it->object, "(merge-base)");
 700        }
 701
 702        if (!active_nr)
 703                read_cache();
 704        for (i = 0; i < active_nr; i++) {
 705                struct cache_entry *ce = active_cache[i];
 706                if (!ce_stage(ce))
 707                        continue;
 708                if (ce_path_match(ce, revs->prune_data)) {
 709                        prune_num++;
 710                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
 711                        prune[prune_num-2] = ce->name;
 712                        prune[prune_num-1] = NULL;
 713                }
 714                while ((i+1 < active_nr) &&
 715                       ce_same_name(ce, active_cache[i+1]))
 716                        i++;
 717        }
 718        revs->prune_data = prune;
 719}
 720
 721int handle_revision_arg(const char *arg, struct rev_info *revs,
 722                        int flags,
 723                        int cant_be_filename)
 724{
 725        char *dotdot;
 726        struct object *object;
 727        unsigned char sha1[20];
 728        int local_flags;
 729
 730        dotdot = strstr(arg, "..");
 731        if (dotdot) {
 732                unsigned char from_sha1[20];
 733                const char *next = dotdot + 2;
 734                const char *this = arg;
 735                int symmetric = *next == '.';
 736                unsigned int flags_exclude = flags ^ UNINTERESTING;
 737
 738                *dotdot = 0;
 739                next += symmetric;
 740
 741                if (!*next)
 742                        next = "HEAD";
 743                if (dotdot == arg)
 744                        this = "HEAD";
 745                if (!get_sha1(this, from_sha1) &&
 746                    !get_sha1(next, sha1)) {
 747                        struct commit *a, *b;
 748                        struct commit_list *exclude;
 749
 750                        a = lookup_commit_reference(from_sha1);
 751                        b = lookup_commit_reference(sha1);
 752                        if (!a || !b) {
 753                                die(symmetric ?
 754                                    "Invalid symmetric difference expression %s...%s" :
 755                                    "Invalid revision range %s..%s",
 756                                    arg, next);
 757                        }
 758
 759                        if (!cant_be_filename) {
 760                                *dotdot = '.';
 761                                verify_non_filename(revs->prefix, arg);
 762                        }
 763
 764                        if (symmetric) {
 765                                exclude = get_merge_bases(a, b, 1);
 766                                add_pending_commit_list(revs, exclude,
 767                                                        flags_exclude);
 768                                free_commit_list(exclude);
 769                                a->object.flags |= flags | SYMMETRIC_LEFT;
 770                        } else
 771                                a->object.flags |= flags_exclude;
 772                        b->object.flags |= flags;
 773                        add_pending_object(revs, &a->object, this);
 774                        add_pending_object(revs, &b->object, next);
 775                        return 0;
 776                }
 777                *dotdot = '.';
 778        }
 779        dotdot = strstr(arg, "^@");
 780        if (dotdot && !dotdot[2]) {
 781                *dotdot = 0;
 782                if (add_parents_only(revs, arg, flags))
 783                        return 0;
 784                *dotdot = '^';
 785        }
 786        dotdot = strstr(arg, "^!");
 787        if (dotdot && !dotdot[2]) {
 788                *dotdot = 0;
 789                if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
 790                        *dotdot = '^';
 791        }
 792
 793        local_flags = 0;
 794        if (*arg == '^') {
 795                local_flags = UNINTERESTING;
 796                arg++;
 797        }
 798        if (get_sha1(arg, sha1))
 799                return -1;
 800        if (!cant_be_filename)
 801                verify_non_filename(revs->prefix, arg);
 802        object = get_reference(revs, arg, sha1, flags ^ local_flags);
 803        add_pending_object(revs, object, arg);
 804        return 0;
 805}
 806
 807static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 808{
 809        if (!revs->grep_filter) {
 810                struct grep_opt *opt = xcalloc(1, sizeof(*opt));
 811                opt->status_only = 1;
 812                opt->pattern_tail = &(opt->pattern_list);
 813                opt->regflags = REG_NEWLINE;
 814                revs->grep_filter = opt;
 815        }
 816        append_grep_pattern(revs->grep_filter, ptn,
 817                            "command line", 0, what);
 818}
 819
 820static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
 821{
 822        char *pat;
 823        const char *prefix;
 824        int patlen, fldlen;
 825
 826        fldlen = strlen(field);
 827        patlen = strlen(pattern);
 828        pat = xmalloc(patlen + fldlen + 10);
 829        prefix = ".*";
 830        if (*pattern == '^') {
 831                prefix = "";
 832                pattern++;
 833        }
 834        sprintf(pat, "^%s %s%s", field, prefix, pattern);
 835        add_grep(revs, pat, GREP_PATTERN_HEAD);
 836}
 837
 838static void add_message_grep(struct rev_info *revs, const char *pattern)
 839{
 840        add_grep(revs, pattern, GREP_PATTERN_BODY);
 841}
 842
 843static void add_ignore_packed(struct rev_info *revs, const char *name)
 844{
 845        int num = ++revs->num_ignore_packed;
 846
 847        revs->ignore_packed = xrealloc(revs->ignore_packed,
 848                                       sizeof(const char **) * (num + 1));
 849        revs->ignore_packed[num-1] = name;
 850        revs->ignore_packed[num] = NULL;
 851}
 852
 853/*
 854 * Parse revision information, filling in the "rev_info" structure,
 855 * and removing the used arguments from the argument list.
 856 *
 857 * Returns the number of arguments left that weren't recognized
 858 * (which are also moved to the head of the argument list)
 859 */
 860int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 861{
 862        int i, flags, seen_dashdash, show_merge;
 863        const char **unrecognized = argv + 1;
 864        int left = 1;
 865        int all_match = 0;
 866
 867        /* First, search for "--" */
 868        seen_dashdash = 0;
 869        for (i = 1; i < argc; i++) {
 870                const char *arg = argv[i];
 871                if (strcmp(arg, "--"))
 872                        continue;
 873                argv[i] = NULL;
 874                argc = i;
 875                revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 876                seen_dashdash = 1;
 877                break;
 878        }
 879
 880        flags = show_merge = 0;
 881        for (i = 1; i < argc; i++) {
 882                const char *arg = argv[i];
 883                if (*arg == '-') {
 884                        int opts;
 885                        if (!prefixcmp(arg, "--max-count=")) {
 886                                revs->max_count = atoi(arg + 12);
 887                                continue;
 888                        }
 889                        if (!prefixcmp(arg, "--skip=")) {
 890                                revs->skip_count = atoi(arg + 7);
 891                                continue;
 892                        }
 893                        /* accept -<digit>, like traditional "head" */
 894                        if ((*arg == '-') && isdigit(arg[1])) {
 895                                revs->max_count = atoi(arg + 1);
 896                                continue;
 897                        }
 898                        if (!strcmp(arg, "-n")) {
 899                                if (argc <= i + 1)
 900                                        die("-n requires an argument");
 901                                revs->max_count = atoi(argv[++i]);
 902                                continue;
 903                        }
 904                        if (!prefixcmp(arg, "-n")) {
 905                                revs->max_count = atoi(arg + 2);
 906                                continue;
 907                        }
 908                        if (!prefixcmp(arg, "--max-age=")) {
 909                                revs->max_age = atoi(arg + 10);
 910                                continue;
 911                        }
 912                        if (!prefixcmp(arg, "--since=")) {
 913                                revs->max_age = approxidate(arg + 8);
 914                                continue;
 915                        }
 916                        if (!prefixcmp(arg, "--after=")) {
 917                                revs->max_age = approxidate(arg + 8);
 918                                continue;
 919                        }
 920                        if (!prefixcmp(arg, "--min-age=")) {
 921                                revs->min_age = atoi(arg + 10);
 922                                continue;
 923                        }
 924                        if (!prefixcmp(arg, "--before=")) {
 925                                revs->min_age = approxidate(arg + 9);
 926                                continue;
 927                        }
 928                        if (!prefixcmp(arg, "--until=")) {
 929                                revs->min_age = approxidate(arg + 8);
 930                                continue;
 931                        }
 932                        if (!strcmp(arg, "--all")) {
 933                                handle_all(revs, flags);
 934                                continue;
 935                        }
 936                        if (!strcmp(arg, "--first-parent")) {
 937                                revs->first_parent_only = 1;
 938                                continue;
 939                        }
 940                        if (!strcmp(arg, "--reflog")) {
 941                                handle_reflog(revs, flags);
 942                                continue;
 943                        }
 944                        if (!strcmp(arg, "-g") ||
 945                                        !strcmp(arg, "--walk-reflogs")) {
 946                                init_reflog_walk(&revs->reflog_info);
 947                                continue;
 948                        }
 949                        if (!strcmp(arg, "--not")) {
 950                                flags ^= UNINTERESTING;
 951                                continue;
 952                        }
 953                        if (!strcmp(arg, "--default")) {
 954                                if (++i >= argc)
 955                                        die("bad --default argument");
 956                                def = argv[i];
 957                                continue;
 958                        }
 959                        if (!strcmp(arg, "--merge")) {
 960                                show_merge = 1;
 961                                continue;
 962                        }
 963                        if (!strcmp(arg, "--topo-order")) {
 964                                revs->topo_order = 1;
 965                                continue;
 966                        }
 967                        if (!strcmp(arg, "--date-order")) {
 968                                revs->lifo = 0;
 969                                revs->topo_order = 1;
 970                                continue;
 971                        }
 972                        if (!strcmp(arg, "--parents")) {
 973                                revs->parents = 1;
 974                                continue;
 975                        }
 976                        if (!strcmp(arg, "--dense")) {
 977                                revs->dense = 1;
 978                                continue;
 979                        }
 980                        if (!strcmp(arg, "--sparse")) {
 981                                revs->dense = 0;
 982                                continue;
 983                        }
 984                        if (!strcmp(arg, "--remove-empty")) {
 985                                revs->remove_empty_trees = 1;
 986                                continue;
 987                        }
 988                        if (!strcmp(arg, "--no-merges")) {
 989                                revs->no_merges = 1;
 990                                continue;
 991                        }
 992                        if (!strcmp(arg, "--boundary")) {
 993                                revs->boundary = 1;
 994                                continue;
 995                        }
 996                        if (!strcmp(arg, "--left-right")) {
 997                                revs->left_right = 1;
 998                                continue;
 999                        }
1000                        if (!strcmp(arg, "--cherry-pick")) {
1001                                revs->cherry_pick = 1;
1002                                continue;
1003                        }
1004                        if (!strcmp(arg, "--objects")) {
1005                                revs->tag_objects = 1;
1006                                revs->tree_objects = 1;
1007                                revs->blob_objects = 1;
1008                                continue;
1009                        }
1010                        if (!strcmp(arg, "--objects-edge")) {
1011                                revs->tag_objects = 1;
1012                                revs->tree_objects = 1;
1013                                revs->blob_objects = 1;
1014                                revs->edge_hint = 1;
1015                                continue;
1016                        }
1017                        if (!strcmp(arg, "--unpacked")) {
1018                                revs->unpacked = 1;
1019                                free(revs->ignore_packed);
1020                                revs->ignore_packed = NULL;
1021                                revs->num_ignore_packed = 0;
1022                                continue;
1023                        }
1024                        if (!prefixcmp(arg, "--unpacked=")) {
1025                                revs->unpacked = 1;
1026                                add_ignore_packed(revs, arg+11);
1027                                continue;
1028                        }
1029                        if (!strcmp(arg, "-r")) {
1030                                revs->diff = 1;
1031                                revs->diffopt.recursive = 1;
1032                                continue;
1033                        }
1034                        if (!strcmp(arg, "-t")) {
1035                                revs->diff = 1;
1036                                revs->diffopt.recursive = 1;
1037                                revs->diffopt.tree_in_recursive = 1;
1038                                continue;
1039                        }
1040                        if (!strcmp(arg, "-m")) {
1041                                revs->ignore_merges = 0;
1042                                continue;
1043                        }
1044                        if (!strcmp(arg, "-c")) {
1045                                revs->diff = 1;
1046                                revs->dense_combined_merges = 0;
1047                                revs->combine_merges = 1;
1048                                continue;
1049                        }
1050                        if (!strcmp(arg, "--cc")) {
1051                                revs->diff = 1;
1052                                revs->dense_combined_merges = 1;
1053                                revs->combine_merges = 1;
1054                                continue;
1055                        }
1056                        if (!strcmp(arg, "-v")) {
1057                                revs->verbose_header = 1;
1058                                continue;
1059                        }
1060                        if (!prefixcmp(arg, "--pretty")) {
1061                                revs->verbose_header = 1;
1062                                revs->commit_format = get_commit_format(arg+8);
1063                                continue;
1064                        }
1065                        if (!strcmp(arg, "--root")) {
1066                                revs->show_root_diff = 1;
1067                                continue;
1068                        }
1069                        if (!strcmp(arg, "--no-commit-id")) {
1070                                revs->no_commit_id = 1;
1071                                continue;
1072                        }
1073                        if (!strcmp(arg, "--always")) {
1074                                revs->always_show_header = 1;
1075                                continue;
1076                        }
1077                        if (!strcmp(arg, "--no-abbrev")) {
1078                                revs->abbrev = 0;
1079                                continue;
1080                        }
1081                        if (!strcmp(arg, "--abbrev")) {
1082                                revs->abbrev = DEFAULT_ABBREV;
1083                                continue;
1084                        }
1085                        if (!prefixcmp(arg, "--abbrev=")) {
1086                                revs->abbrev = strtoul(arg + 9, NULL, 10);
1087                                if (revs->abbrev < MINIMUM_ABBREV)
1088                                        revs->abbrev = MINIMUM_ABBREV;
1089                                else if (revs->abbrev > 40)
1090                                        revs->abbrev = 40;
1091                                continue;
1092                        }
1093                        if (!strcmp(arg, "--abbrev-commit")) {
1094                                revs->abbrev_commit = 1;
1095                                continue;
1096                        }
1097                        if (!strcmp(arg, "--full-diff")) {
1098                                revs->diff = 1;
1099                                revs->full_diff = 1;
1100                                continue;
1101                        }
1102                        if (!strcmp(arg, "--full-history")) {
1103                                revs->simplify_history = 0;
1104                                continue;
1105                        }
1106                        if (!strcmp(arg, "--relative-date")) {
1107                                revs->relative_date = 1;
1108                                continue;
1109                        }
1110
1111                        /*
1112                         * Grepping the commit log
1113                         */
1114                        if (!prefixcmp(arg, "--author=")) {
1115                                add_header_grep(revs, "author", arg+9);
1116                                continue;
1117                        }
1118                        if (!prefixcmp(arg, "--committer=")) {
1119                                add_header_grep(revs, "committer", arg+12);
1120                                continue;
1121                        }
1122                        if (!prefixcmp(arg, "--grep=")) {
1123                                add_message_grep(revs, arg+7);
1124                                continue;
1125                        }
1126                        if (!strcmp(arg, "--all-match")) {
1127                                all_match = 1;
1128                                continue;
1129                        }
1130                        if (!prefixcmp(arg, "--encoding=")) {
1131                                arg += 11;
1132                                if (strcmp(arg, "none"))
1133                                        git_log_output_encoding = xstrdup(arg);
1134                                else
1135                                        git_log_output_encoding = "";
1136                                continue;
1137                        }
1138                        if (!strcmp(arg, "--reverse")) {
1139                                revs->reverse ^= 1;
1140                                continue;
1141                        }
1142
1143                        opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
1144                        if (opts > 0) {
1145                                revs->diff = 1;
1146                                i += opts - 1;
1147                                continue;
1148                        }
1149                        *unrecognized++ = arg;
1150                        left++;
1151                        continue;
1152                }
1153
1154                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1155                        int j;
1156                        if (seen_dashdash || *arg == '^')
1157                                die("bad revision '%s'", arg);
1158
1159                        /* If we didn't have a "--":
1160                         * (1) all filenames must exist;
1161                         * (2) all rev-args must not be interpretable
1162                         *     as a valid filename.
1163                         * but the latter we have checked in the main loop.
1164                         */
1165                        for (j = i; j < argc; j++)
1166                                verify_filename(revs->prefix, argv[j]);
1167
1168                        revs->prune_data = get_pathspec(revs->prefix,
1169                                                        argv + i);
1170                        break;
1171                }
1172        }
1173
1174        if (show_merge)
1175                prepare_show_merge(revs);
1176        if (def && !revs->pending.nr) {
1177                unsigned char sha1[20];
1178                struct object *object;
1179                if (get_sha1(def, sha1))
1180                        die("bad default revision '%s'", def);
1181                object = get_reference(revs, def, sha1, 0);
1182                add_pending_object(revs, object, def);
1183        }
1184
1185        if (revs->topo_order)
1186                revs->limited = 1;
1187
1188        if (revs->prune_data) {
1189                diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1190                revs->prune_fn = try_to_simplify_commit;
1191                if (!revs->full_diff)
1192                        diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1193        }
1194        if (revs->combine_merges) {
1195                revs->ignore_merges = 0;
1196                if (revs->dense_combined_merges && !revs->diffopt.output_format)
1197                        revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1198        }
1199        revs->diffopt.abbrev = revs->abbrev;
1200        if (diff_setup_done(&revs->diffopt) < 0)
1201                die("diff_setup_done failed");
1202
1203        if (revs->grep_filter) {
1204                revs->grep_filter->all_match = all_match;
1205                compile_grep_patterns(revs->grep_filter);
1206        }
1207
1208        return left;
1209}
1210
1211void prepare_revision_walk(struct rev_info *revs)
1212{
1213        int nr = revs->pending.nr;
1214        struct object_array_entry *e, *list;
1215
1216        e = list = revs->pending.objects;
1217        revs->pending.nr = 0;
1218        revs->pending.alloc = 0;
1219        revs->pending.objects = NULL;
1220        while (--nr >= 0) {
1221                struct commit *commit = handle_commit(revs, e->item, e->name);
1222                if (commit) {
1223                        if (!(commit->object.flags & SEEN)) {
1224                                commit->object.flags |= SEEN;
1225                                insert_by_date(commit, &revs->commits);
1226                        }
1227                }
1228                e++;
1229        }
1230        free(list);
1231
1232        if (revs->no_walk)
1233                return;
1234        if (revs->limited)
1235                limit_list(revs);
1236        if (revs->topo_order)
1237                sort_in_topological_order_fn(&revs->commits, revs->lifo,
1238                                             revs->topo_setter,
1239                                             revs->topo_getter);
1240}
1241
1242static int rewrite_one(struct rev_info *revs, struct commit **pp)
1243{
1244        for (;;) {
1245                struct commit *p = *pp;
1246                if (!revs->limited)
1247                        add_parents_to_list(revs, p, &revs->commits);
1248                if (p->parents && p->parents->next)
1249                        return 0;
1250                if (p->object.flags & (TREECHANGE | UNINTERESTING))
1251                        return 0;
1252                if (!p->parents)
1253                        return -1;
1254                *pp = p->parents->item;
1255        }
1256}
1257
1258static void rewrite_parents(struct rev_info *revs, struct commit *commit)
1259{
1260        struct commit_list **pp = &commit->parents;
1261        while (*pp) {
1262                struct commit_list *parent = *pp;
1263                if (rewrite_one(revs, &parent->item) < 0) {
1264                        *pp = parent->next;
1265                        continue;
1266                }
1267                pp = &parent->next;
1268        }
1269}
1270
1271static int commit_match(struct commit *commit, struct rev_info *opt)
1272{
1273        if (!opt->grep_filter)
1274                return 1;
1275        return grep_buffer(opt->grep_filter,
1276                           NULL, /* we say nothing, not even filename */
1277                           commit->buffer, strlen(commit->buffer));
1278}
1279
1280static struct commit *get_revision_1(struct rev_info *revs)
1281{
1282        if (!revs->commits)
1283                return NULL;
1284
1285        do {
1286                struct commit_list *entry = revs->commits;
1287                struct commit *commit = entry->item;
1288
1289                revs->commits = entry->next;
1290                free(entry);
1291
1292                if (revs->reflog_info)
1293                        fake_reflog_parent(revs->reflog_info, commit);
1294
1295                /*
1296                 * If we haven't done the list limiting, we need to look at
1297                 * the parents here. We also need to do the date-based limiting
1298                 * that we'd otherwise have done in limit_list().
1299                 */
1300                if (!revs->limited) {
1301                        if (revs->max_age != -1 &&
1302                            (commit->date < revs->max_age))
1303                                continue;
1304                        add_parents_to_list(revs, commit, &revs->commits);
1305                }
1306                if (commit->object.flags & SHOWN)
1307                        continue;
1308
1309                if (revs->unpacked && has_sha1_pack(commit->object.sha1,
1310                                                    revs->ignore_packed))
1311                    continue;
1312
1313                if (commit->object.flags & UNINTERESTING)
1314                        continue;
1315                if (revs->min_age != -1 && (commit->date > revs->min_age))
1316                        continue;
1317                if (revs->no_merges &&
1318                    commit->parents && commit->parents->next)
1319                        continue;
1320                if (!commit_match(commit, revs))
1321                        continue;
1322                if (revs->prune_fn && revs->dense) {
1323                        /* Commit without changes? */
1324                        if (!(commit->object.flags & TREECHANGE)) {
1325                                /* drop merges unless we want parenthood */
1326                                if (!revs->parents)
1327                                        continue;
1328                                /* non-merge - always ignore it */
1329                                if (!commit->parents || !commit->parents->next)
1330                                        continue;
1331                        }
1332                        if (revs->parents)
1333                                rewrite_parents(revs, commit);
1334                }
1335                return commit;
1336        } while (revs->commits);
1337        return NULL;
1338}
1339
1340static void gc_boundary(struct object_array *array)
1341{
1342        unsigned nr = array->nr;
1343        unsigned alloc = array->alloc;
1344        struct object_array_entry *objects = array->objects;
1345
1346        if (alloc <= nr) {
1347                unsigned i, j;
1348                for (i = j = 0; i < nr; i++) {
1349                        if (objects[i].item->flags & SHOWN)
1350                                continue;
1351                        if (i != j)
1352                                objects[j] = objects[i];
1353                        j++;
1354                }
1355                for (i = j; i < nr; i++)
1356                        objects[i].item = NULL;
1357                array->nr = j;
1358        }
1359}
1360
1361struct commit *get_revision(struct rev_info *revs)
1362{
1363        struct commit *c = NULL;
1364        struct commit_list *l;
1365
1366        if (revs->boundary == 2) {
1367                unsigned i;
1368                struct object_array *array = &revs->boundary_commits;
1369                struct object_array_entry *objects = array->objects;
1370                for (i = 0; i < array->nr; i++) {
1371                        c = (struct commit *)(objects[i].item);
1372                        if (!c)
1373                                continue;
1374                        if (!(c->object.flags & CHILD_SHOWN))
1375                                continue;
1376                        if (!(c->object.flags & SHOWN))
1377                                break;
1378                }
1379                if (array->nr <= i)
1380                        return NULL;
1381
1382                c->object.flags |= SHOWN | BOUNDARY;
1383                return c;
1384        }
1385
1386        if (revs->reverse) {
1387                int limit = -1;
1388
1389                if (0 <= revs->max_count) {
1390                        limit = revs->max_count;
1391                        if (0 < revs->skip_count)
1392                                limit += revs->skip_count;
1393                }
1394                l = NULL;
1395                while ((c = get_revision_1(revs))) {
1396                        commit_list_insert(c, &l);
1397                        if ((0 < limit) && !--limit)
1398                                break;
1399                }
1400                revs->commits = l;
1401                revs->reverse = 0;
1402                revs->max_count = -1;
1403                c = NULL;
1404        }
1405
1406        /*
1407         * Now pick up what they want to give us
1408         */
1409        c = get_revision_1(revs);
1410        if (c) {
1411                while (0 < revs->skip_count) {
1412                        revs->skip_count--;
1413                        c = get_revision_1(revs);
1414                        if (!c)
1415                                break;
1416                }
1417        }
1418
1419        /*
1420         * Check the max_count.
1421         */
1422        switch (revs->max_count) {
1423        case -1:
1424                break;
1425        case 0:
1426                c = NULL;
1427                break;
1428        default:
1429                revs->max_count--;
1430        }
1431
1432        if (c)
1433                c->object.flags |= SHOWN;
1434
1435        if (!revs->boundary) {
1436                return c;
1437        }
1438
1439        if (!c) {
1440                /*
1441                 * get_revision_1() runs out the commits, and
1442                 * we are done computing the boundaries.
1443                 * switch to boundary commits output mode.
1444                 */
1445                revs->boundary = 2;
1446                return get_revision(revs);
1447        }
1448
1449        /*
1450         * boundary commits are the commits that are parents of the
1451         * ones we got from get_revision_1() but they themselves are
1452         * not returned from get_revision_1().  Before returning
1453         * 'c', we need to mark its parents that they could be boundaries.
1454         */
1455
1456        for (l = c->parents; l; l = l->next) {
1457                struct object *p;
1458                p = &(l->item->object);
1459                if (p->flags & (CHILD_SHOWN | SHOWN))
1460                        continue;
1461                p->flags |= CHILD_SHOWN;
1462                gc_boundary(&revs->boundary_commits);
1463                add_object_array(p, NULL, &revs->boundary_commits);
1464        }
1465
1466        return c;
1467}