revision.con commit git-tar-tree: Move code for git-archive --format=tar to archive-tar.c (3d74982)
   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 <regex.h>
  10#include "grep.h"
  11
  12static char *path_name(struct name_path *path, const char *name)
  13{
  14        struct name_path *p;
  15        char *n, *m;
  16        int nlen = strlen(name);
  17        int len = nlen + 1;
  18
  19        for (p = path; p; p = p->up) {
  20                if (p->elem_len)
  21                        len += p->elem_len + 1;
  22        }
  23        n = xmalloc(len);
  24        m = n + len - (nlen + 1);
  25        strcpy(m, name);
  26        for (p = path; p; p = p->up) {
  27                if (p->elem_len) {
  28                        m -= p->elem_len + 1;
  29                        memcpy(m, p->elem, p->elem_len);
  30                        m[p->elem_len] = '/';
  31                }
  32        }
  33        return n;
  34}
  35
  36void add_object(struct object *obj,
  37                struct object_array *p,
  38                struct name_path *path,
  39                const char *name)
  40{
  41        add_object_array(obj, path_name(path, name), p);
  42}
  43
  44static void mark_blob_uninteresting(struct blob *blob)
  45{
  46        if (blob->object.flags & UNINTERESTING)
  47                return;
  48        blob->object.flags |= UNINTERESTING;
  49}
  50
  51void mark_tree_uninteresting(struct tree *tree)
  52{
  53        struct tree_desc desc;
  54        struct name_entry entry;
  55        struct object *obj = &tree->object;
  56
  57        if (obj->flags & UNINTERESTING)
  58                return;
  59        obj->flags |= UNINTERESTING;
  60        if (!has_sha1_file(obj->sha1))
  61                return;
  62        if (parse_tree(tree) < 0)
  63                die("bad tree %s", sha1_to_hex(obj->sha1));
  64
  65        desc.buf = tree->buffer;
  66        desc.size = 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        add_object_array(obj, name, &revs->pending);
 120}
 121
 122static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 123{
 124        struct object *object;
 125
 126        object = parse_object(sha1);
 127        if (!object)
 128                die("bad object %s", name);
 129        object->flags |= flags;
 130        return object;
 131}
 132
 133static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 134{
 135        unsigned long flags = object->flags;
 136
 137        /*
 138         * Tag object? Look what it points to..
 139         */
 140        while (object->type == OBJ_TAG) {
 141                struct tag *tag = (struct tag *) object;
 142                if (revs->tag_objects && !(flags & UNINTERESTING))
 143                        add_pending_object(revs, object, tag->tag);
 144                object = parse_object(tag->tagged->sha1);
 145                if (!object)
 146                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 147        }
 148
 149        /*
 150         * Commit object? Just return it, we'll do all the complex
 151         * reachability crud.
 152         */
 153        if (object->type == OBJ_COMMIT) {
 154                struct commit *commit = (struct commit *)object;
 155                if (parse_commit(commit) < 0)
 156                        die("unable to parse commit %s", name);
 157                if (flags & UNINTERESTING) {
 158                        commit->object.flags |= UNINTERESTING;
 159                        mark_parents_uninteresting(commit);
 160                        revs->limited = 1;
 161                }
 162                return commit;
 163        }
 164
 165        /*
 166         * Tree object? Either mark it uniniteresting, or add it
 167         * to the list of objects to look at later..
 168         */
 169        if (object->type == OBJ_TREE) {
 170                struct tree *tree = (struct tree *)object;
 171                if (!revs->tree_objects)
 172                        return NULL;
 173                if (flags & UNINTERESTING) {
 174                        mark_tree_uninteresting(tree);
 175                        return NULL;
 176                }
 177                add_pending_object(revs, object, "");
 178                return NULL;
 179        }
 180
 181        /*
 182         * Blob object? You know the drill by now..
 183         */
 184        if (object->type == OBJ_BLOB) {
 185                struct blob *blob = (struct blob *)object;
 186                if (!revs->blob_objects)
 187                        return NULL;
 188                if (flags & UNINTERESTING) {
 189                        mark_blob_uninteresting(blob);
 190                        return NULL;
 191                }
 192                add_pending_object(revs, object, "");
 193                return NULL;
 194        }
 195        die("%s is unknown object", name);
 196}
 197
 198static int everybody_uninteresting(struct commit_list *orig)
 199{
 200        struct commit_list *list = orig;
 201        while (list) {
 202                struct commit *commit = list->item;
 203                list = list->next;
 204                if (commit->object.flags & UNINTERESTING)
 205                        continue;
 206                return 0;
 207        }
 208        return 1;
 209}
 210
 211static int tree_difference = REV_TREE_SAME;
 212
 213static void file_add_remove(struct diff_options *options,
 214                    int addremove, unsigned mode,
 215                    const unsigned char *sha1,
 216                    const char *base, const char *path)
 217{
 218        int diff = REV_TREE_DIFFERENT;
 219
 220        /*
 221         * Is it an add of a new file? It means that the old tree
 222         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 223         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 224         * (and if it already was "REV_TREE_NEW", we'll keep it
 225         * "REV_TREE_NEW" of course).
 226         */
 227        if (addremove == '+') {
 228                diff = tree_difference;
 229                if (diff != REV_TREE_SAME)
 230                        return;
 231                diff = REV_TREE_NEW;
 232        }
 233        tree_difference = diff;
 234}
 235
 236static void file_change(struct diff_options *options,
 237                 unsigned old_mode, unsigned new_mode,
 238                 const unsigned char *old_sha1,
 239                 const unsigned char *new_sha1,
 240                 const char *base, const char *path)
 241{
 242        tree_difference = REV_TREE_DIFFERENT;
 243}
 244
 245int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 246{
 247        if (!t1)
 248                return REV_TREE_NEW;
 249        if (!t2)
 250                return REV_TREE_DIFFERENT;
 251        tree_difference = REV_TREE_SAME;
 252        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 253                           &revs->pruning) < 0)
 254                return REV_TREE_DIFFERENT;
 255        return tree_difference;
 256}
 257
 258int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 259{
 260        int retval;
 261        void *tree;
 262        struct tree_desc empty, real;
 263
 264        if (!t1)
 265                return 0;
 266
 267        tree = read_object_with_reference(t1->object.sha1, tree_type, &real.size, NULL);
 268        if (!tree)
 269                return 0;
 270        real.buf = tree;
 271
 272        empty.buf = "";
 273        empty.size = 0;
 274
 275        tree_difference = 0;
 276        retval = diff_tree(&empty, &real, "", &revs->pruning);
 277        free(tree);
 278
 279        return retval >= 0 && !tree_difference;
 280}
 281
 282static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 283{
 284        struct commit_list **pp, *parent;
 285        int tree_changed = 0, tree_same = 0;
 286
 287        if (!commit->tree)
 288                return;
 289
 290        if (!commit->parents) {
 291                if (!rev_same_tree_as_empty(revs, commit->tree))
 292                        commit->object.flags |= TREECHANGE;
 293                return;
 294        }
 295
 296        pp = &commit->parents;
 297        while ((parent = *pp) != NULL) {
 298                struct commit *p = parent->item;
 299
 300                parse_commit(p);
 301                switch (rev_compare_tree(revs, p->tree, commit->tree)) {
 302                case REV_TREE_SAME:
 303                        tree_same = 1;
 304                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 305                                /* Even if a merge with an uninteresting
 306                                 * side branch brought the entire change
 307                                 * we are interested in, we do not want
 308                                 * to lose the other branches of this
 309                                 * merge, so we just keep going.
 310                                 */
 311                                pp = &parent->next;
 312                                continue;
 313                        }
 314                        parent->next = NULL;
 315                        commit->parents = parent;
 316                        return;
 317
 318                case REV_TREE_NEW:
 319                        if (revs->remove_empty_trees &&
 320                            rev_same_tree_as_empty(revs, p->tree)) {
 321                                /* We are adding all the specified
 322                                 * paths from this parent, so the
 323                                 * history beyond this parent is not
 324                                 * interesting.  Remove its parents
 325                                 * (they are grandparents for us).
 326                                 * IOW, we pretend this parent is a
 327                                 * "root" commit.
 328                                 */
 329                                parse_commit(p);
 330                                p->parents = NULL;
 331                        }
 332                /* fallthrough */
 333                case REV_TREE_DIFFERENT:
 334                        tree_changed = 1;
 335                        pp = &parent->next;
 336                        continue;
 337                }
 338                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 339        }
 340        if (tree_changed && !tree_same)
 341                commit->object.flags |= TREECHANGE;
 342}
 343
 344static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 345{
 346        struct commit_list *parent = commit->parents;
 347
 348        if (commit->object.flags & ADDED)
 349                return;
 350        commit->object.flags |= ADDED;
 351
 352        /*
 353         * If the commit is uninteresting, don't try to
 354         * prune parents - we want the maximal uninteresting
 355         * set.
 356         *
 357         * Normally we haven't parsed the parent
 358         * yet, so we won't have a parent of a parent
 359         * here. However, it may turn out that we've
 360         * reached this commit some other way (where it
 361         * wasn't uninteresting), in which case we need
 362         * to mark its parents recursively too..
 363         */
 364        if (commit->object.flags & UNINTERESTING) {
 365                while (parent) {
 366                        struct commit *p = parent->item;
 367                        parent = parent->next;
 368                        parse_commit(p);
 369                        p->object.flags |= UNINTERESTING;
 370                        if (p->parents)
 371                                mark_parents_uninteresting(p);
 372                        if (p->object.flags & SEEN)
 373                                continue;
 374                        p->object.flags |= SEEN;
 375                        insert_by_date(p, list);
 376                }
 377                return;
 378        }
 379
 380        /*
 381         * Ok, the commit wasn't uninteresting. Try to
 382         * simplify the commit history and find the parent
 383         * that has no differences in the path set if one exists.
 384         */
 385        if (revs->prune_fn)
 386                revs->prune_fn(revs, commit);
 387
 388        if (revs->no_walk)
 389                return;
 390
 391        parent = commit->parents;
 392        while (parent) {
 393                struct commit *p = parent->item;
 394
 395                parent = parent->next;
 396
 397                parse_commit(p);
 398                if (p->object.flags & SEEN)
 399                        continue;
 400                p->object.flags |= SEEN;
 401                insert_by_date(p, list);
 402        }
 403}
 404
 405static void limit_list(struct rev_info *revs)
 406{
 407        struct commit_list *list = revs->commits;
 408        struct commit_list *newlist = NULL;
 409        struct commit_list **p = &newlist;
 410
 411        while (list) {
 412                struct commit_list *entry = list;
 413                struct commit *commit = list->item;
 414                struct object *obj = &commit->object;
 415
 416                list = list->next;
 417                free(entry);
 418
 419                if (revs->max_age != -1 && (commit->date < revs->max_age))
 420                        obj->flags |= UNINTERESTING;
 421                if (revs->unpacked &&
 422                    has_sha1_pack(obj->sha1, revs->ignore_packed))
 423                        obj->flags |= UNINTERESTING;
 424                add_parents_to_list(revs, commit, &list);
 425                if (obj->flags & UNINTERESTING) {
 426                        mark_parents_uninteresting(commit);
 427                        if (everybody_uninteresting(list))
 428                                break;
 429                        continue;
 430                }
 431                if (revs->min_age != -1 && (commit->date > revs->min_age))
 432                        continue;
 433                p = &commit_list_insert(commit, p)->next;
 434        }
 435        if (revs->boundary) {
 436                /* mark the ones that are on the result list first */
 437                for (list = newlist; list; list = list->next) {
 438                        struct commit *commit = list->item;
 439                        commit->object.flags |= TMP_MARK;
 440                }
 441                for (list = newlist; list; list = list->next) {
 442                        struct commit *commit = list->item;
 443                        struct object *obj = &commit->object;
 444                        struct commit_list *parent;
 445                        if (obj->flags & UNINTERESTING)
 446                                continue;
 447                        for (parent = commit->parents;
 448                             parent;
 449                             parent = parent->next) {
 450                                struct commit *pcommit = parent->item;
 451                                if (!(pcommit->object.flags & UNINTERESTING))
 452                                        continue;
 453                                pcommit->object.flags |= BOUNDARY;
 454                                if (pcommit->object.flags & TMP_MARK)
 455                                        continue;
 456                                pcommit->object.flags |= TMP_MARK;
 457                                p = &commit_list_insert(pcommit, p)->next;
 458                        }
 459                }
 460                for (list = newlist; list; list = list->next) {
 461                        struct commit *commit = list->item;
 462                        commit->object.flags &= ~TMP_MARK;
 463                }
 464        }
 465        revs->commits = newlist;
 466}
 467
 468static int all_flags;
 469static struct rev_info *all_revs;
 470
 471static int handle_one_ref(const char *path, const unsigned char *sha1)
 472{
 473        struct object *object = get_reference(all_revs, path, sha1, all_flags);
 474        add_pending_object(all_revs, object, "");
 475        return 0;
 476}
 477
 478static void handle_all(struct rev_info *revs, unsigned flags)
 479{
 480        all_revs = revs;
 481        all_flags = flags;
 482        for_each_ref(handle_one_ref);
 483}
 484
 485static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 486{
 487        unsigned char sha1[20];
 488        struct object *it;
 489        struct commit *commit;
 490        struct commit_list *parents;
 491
 492        if (*arg == '^') {
 493                flags ^= UNINTERESTING;
 494                arg++;
 495        }
 496        if (get_sha1(arg, sha1))
 497                return 0;
 498        while (1) {
 499                it = get_reference(revs, arg, sha1, 0);
 500                if (it->type != OBJ_TAG)
 501                        break;
 502                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 503        }
 504        if (it->type != OBJ_COMMIT)
 505                return 0;
 506        commit = (struct commit *)it;
 507        for (parents = commit->parents; parents; parents = parents->next) {
 508                it = &parents->item->object;
 509                it->flags |= flags;
 510                add_pending_object(revs, it, arg);
 511        }
 512        return 1;
 513}
 514
 515void init_revisions(struct rev_info *revs, const char *prefix)
 516{
 517        memset(revs, 0, sizeof(*revs));
 518
 519        revs->abbrev = DEFAULT_ABBREV;
 520        revs->ignore_merges = 1;
 521        revs->simplify_history = 1;
 522        revs->pruning.recursive = 1;
 523        revs->pruning.add_remove = file_add_remove;
 524        revs->pruning.change = file_change;
 525        revs->lifo = 1;
 526        revs->dense = 1;
 527        revs->prefix = prefix;
 528        revs->max_age = -1;
 529        revs->min_age = -1;
 530        revs->max_count = -1;
 531
 532        revs->prune_fn = NULL;
 533        revs->prune_data = NULL;
 534
 535        revs->topo_setter = topo_sort_default_setter;
 536        revs->topo_getter = topo_sort_default_getter;
 537
 538        revs->commit_format = CMIT_FMT_DEFAULT;
 539
 540        diff_setup(&revs->diffopt);
 541}
 542
 543static void add_pending_commit_list(struct rev_info *revs,
 544                                    struct commit_list *commit_list,
 545                                    unsigned int flags)
 546{
 547        while (commit_list) {
 548                struct object *object = &commit_list->item->object;
 549                object->flags |= flags;
 550                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 551                commit_list = commit_list->next;
 552        }
 553}
 554
 555static void prepare_show_merge(struct rev_info *revs)
 556{
 557        struct commit_list *bases;
 558        struct commit *head, *other;
 559        unsigned char sha1[20];
 560        const char **prune = NULL;
 561        int i, prune_num = 1; /* counting terminating NULL */
 562
 563        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 564                die("--merge without HEAD?");
 565        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 566                die("--merge without MERGE_HEAD?");
 567        add_pending_object(revs, &head->object, "HEAD");
 568        add_pending_object(revs, &other->object, "MERGE_HEAD");
 569        bases = get_merge_bases(head, other, 1);
 570        while (bases) {
 571                struct commit *it = bases->item;
 572                struct commit_list *n = bases->next;
 573                free(bases);
 574                bases = n;
 575                it->object.flags |= UNINTERESTING;
 576                add_pending_object(revs, &it->object, "(merge-base)");
 577        }
 578
 579        if (!active_nr)
 580                read_cache();
 581        for (i = 0; i < active_nr; i++) {
 582                struct cache_entry *ce = active_cache[i];
 583                if (!ce_stage(ce))
 584                        continue;
 585                if (ce_path_match(ce, revs->prune_data)) {
 586                        prune_num++;
 587                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
 588                        prune[prune_num-2] = ce->name;
 589                        prune[prune_num-1] = NULL;
 590                }
 591                while ((i+1 < active_nr) &&
 592                       ce_same_name(ce, active_cache[i+1]))
 593                        i++;
 594        }
 595        revs->prune_data = prune;
 596}
 597
 598int handle_revision_arg(const char *arg, struct rev_info *revs,
 599                        int flags,
 600                        int cant_be_filename)
 601{
 602        char *dotdot;
 603        struct object *object;
 604        unsigned char sha1[20];
 605        int local_flags;
 606
 607        dotdot = strstr(arg, "..");
 608        if (dotdot) {
 609                unsigned char from_sha1[20];
 610                const char *next = dotdot + 2;
 611                const char *this = arg;
 612                int symmetric = *next == '.';
 613                unsigned int flags_exclude = flags ^ UNINTERESTING;
 614
 615                *dotdot = 0;
 616                next += symmetric;
 617
 618                if (!*next)
 619                        next = "HEAD";
 620                if (dotdot == arg)
 621                        this = "HEAD";
 622                if (!get_sha1(this, from_sha1) &&
 623                    !get_sha1(next, sha1)) {
 624                        struct commit *a, *b;
 625                        struct commit_list *exclude;
 626
 627                        a = lookup_commit_reference(from_sha1);
 628                        b = lookup_commit_reference(sha1);
 629                        if (!a || !b) {
 630                                die(symmetric ?
 631                                    "Invalid symmetric difference expression %s...%s" :
 632                                    "Invalid revision range %s..%s",
 633                                    arg, next);
 634                        }
 635
 636                        if (!cant_be_filename) {
 637                                *dotdot = '.';
 638                                verify_non_filename(revs->prefix, arg);
 639                        }
 640
 641                        if (symmetric) {
 642                                exclude = get_merge_bases(a, b, 1);
 643                                add_pending_commit_list(revs, exclude,
 644                                                        flags_exclude);
 645                                free_commit_list(exclude);
 646                                a->object.flags |= flags;
 647                        } else
 648                                a->object.flags |= flags_exclude;
 649                        b->object.flags |= flags;
 650                        add_pending_object(revs, &a->object, this);
 651                        add_pending_object(revs, &b->object, next);
 652                        return 0;
 653                }
 654                *dotdot = '.';
 655        }
 656        dotdot = strstr(arg, "^@");
 657        if (dotdot && !dotdot[2]) {
 658                *dotdot = 0;
 659                if (add_parents_only(revs, arg, flags))
 660                        return 0;
 661                *dotdot = '^';
 662        }
 663        local_flags = 0;
 664        if (*arg == '^') {
 665                local_flags = UNINTERESTING;
 666                arg++;
 667        }
 668        if (get_sha1(arg, sha1))
 669                return -1;
 670        if (!cant_be_filename)
 671                verify_non_filename(revs->prefix, arg);
 672        object = get_reference(revs, arg, sha1, flags ^ local_flags);
 673        add_pending_object(revs, object, arg);
 674        return 0;
 675}
 676
 677static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 678{
 679        if (!revs->grep_filter) {
 680                struct grep_opt *opt = xcalloc(1, sizeof(*opt));
 681                opt->status_only = 1;
 682                opt->pattern_tail = &(opt->pattern_list);
 683                opt->regflags = REG_NEWLINE;
 684                revs->grep_filter = opt;
 685        }
 686        append_grep_pattern(revs->grep_filter, ptn,
 687                            "command line", 0, what);
 688}
 689
 690static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
 691{
 692        char *pat;
 693        const char *prefix;
 694        int patlen, fldlen;
 695
 696        fldlen = strlen(field);
 697        patlen = strlen(pattern);
 698        pat = xmalloc(patlen + fldlen + 10);
 699        prefix = ".*";
 700        if (*pattern == '^') {
 701                prefix = "";
 702                pattern++;
 703        }
 704        sprintf(pat, "^%s %s%s", field, prefix, pattern);
 705        add_grep(revs, pat, GREP_PATTERN_HEAD);
 706}
 707
 708static void add_message_grep(struct rev_info *revs, const char *pattern)
 709{
 710        add_grep(revs, pattern, GREP_PATTERN_BODY);
 711}
 712
 713static void add_ignore_packed(struct rev_info *revs, const char *name)
 714{
 715        int num = ++revs->num_ignore_packed;
 716
 717        revs->ignore_packed = xrealloc(revs->ignore_packed,
 718                                       sizeof(const char **) * (num + 1));
 719        revs->ignore_packed[num-1] = name;
 720        revs->ignore_packed[num] = NULL;
 721}
 722
 723/*
 724 * Parse revision information, filling in the "rev_info" structure,
 725 * and removing the used arguments from the argument list.
 726 *
 727 * Returns the number of arguments left that weren't recognized
 728 * (which are also moved to the head of the argument list)
 729 */
 730int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 731{
 732        int i, flags, seen_dashdash, show_merge;
 733        const char **unrecognized = argv + 1;
 734        int left = 1;
 735
 736        /* First, search for "--" */
 737        seen_dashdash = 0;
 738        for (i = 1; i < argc; i++) {
 739                const char *arg = argv[i];
 740                if (strcmp(arg, "--"))
 741                        continue;
 742                argv[i] = NULL;
 743                argc = i;
 744                revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 745                seen_dashdash = 1;
 746                break;
 747        }
 748
 749        flags = show_merge = 0;
 750        for (i = 1; i < argc; i++) {
 751                const char *arg = argv[i];
 752                if (*arg == '-') {
 753                        int opts;
 754                        if (!strncmp(arg, "--max-count=", 12)) {
 755                                revs->max_count = atoi(arg + 12);
 756                                continue;
 757                        }
 758                        /* accept -<digit>, like traditional "head" */
 759                        if ((*arg == '-') && isdigit(arg[1])) {
 760                                revs->max_count = atoi(arg + 1);
 761                                continue;
 762                        }
 763                        if (!strcmp(arg, "-n")) {
 764                                if (argc <= i + 1)
 765                                        die("-n requires an argument");
 766                                revs->max_count = atoi(argv[++i]);
 767                                continue;
 768                        }
 769                        if (!strncmp(arg,"-n",2)) {
 770                                revs->max_count = atoi(arg + 2);
 771                                continue;
 772                        }
 773                        if (!strncmp(arg, "--max-age=", 10)) {
 774                                revs->max_age = atoi(arg + 10);
 775                                continue;
 776                        }
 777                        if (!strncmp(arg, "--since=", 8)) {
 778                                revs->max_age = approxidate(arg + 8);
 779                                continue;
 780                        }
 781                        if (!strncmp(arg, "--after=", 8)) {
 782                                revs->max_age = approxidate(arg + 8);
 783                                continue;
 784                        }
 785                        if (!strncmp(arg, "--min-age=", 10)) {
 786                                revs->min_age = atoi(arg + 10);
 787                                continue;
 788                        }
 789                        if (!strncmp(arg, "--before=", 9)) {
 790                                revs->min_age = approxidate(arg + 9);
 791                                continue;
 792                        }
 793                        if (!strncmp(arg, "--until=", 8)) {
 794                                revs->min_age = approxidate(arg + 8);
 795                                continue;
 796                        }
 797                        if (!strcmp(arg, "--all")) {
 798                                handle_all(revs, flags);
 799                                continue;
 800                        }
 801                        if (!strcmp(arg, "--not")) {
 802                                flags ^= UNINTERESTING;
 803                                continue;
 804                        }
 805                        if (!strcmp(arg, "--default")) {
 806                                if (++i >= argc)
 807                                        die("bad --default argument");
 808                                def = argv[i];
 809                                continue;
 810                        }
 811                        if (!strcmp(arg, "--merge")) {
 812                                show_merge = 1;
 813                                continue;
 814                        }
 815                        if (!strcmp(arg, "--topo-order")) {
 816                                revs->topo_order = 1;
 817                                continue;
 818                        }
 819                        if (!strcmp(arg, "--date-order")) {
 820                                revs->lifo = 0;
 821                                revs->topo_order = 1;
 822                                continue;
 823                        }
 824                        if (!strcmp(arg, "--parents")) {
 825                                revs->parents = 1;
 826                                continue;
 827                        }
 828                        if (!strcmp(arg, "--dense")) {
 829                                revs->dense = 1;
 830                                continue;
 831                        }
 832                        if (!strcmp(arg, "--sparse")) {
 833                                revs->dense = 0;
 834                                continue;
 835                        }
 836                        if (!strcmp(arg, "--remove-empty")) {
 837                                revs->remove_empty_trees = 1;
 838                                continue;
 839                        }
 840                        if (!strcmp(arg, "--no-merges")) {
 841                                revs->no_merges = 1;
 842                                continue;
 843                        }
 844                        if (!strcmp(arg, "--boundary")) {
 845                                revs->boundary = 1;
 846                                continue;
 847                        }
 848                        if (!strcmp(arg, "--objects")) {
 849                                revs->tag_objects = 1;
 850                                revs->tree_objects = 1;
 851                                revs->blob_objects = 1;
 852                                continue;
 853                        }
 854                        if (!strcmp(arg, "--objects-edge")) {
 855                                revs->tag_objects = 1;
 856                                revs->tree_objects = 1;
 857                                revs->blob_objects = 1;
 858                                revs->edge_hint = 1;
 859                                continue;
 860                        }
 861                        if (!strcmp(arg, "--unpacked")) {
 862                                revs->unpacked = 1;
 863                                free(revs->ignore_packed);
 864                                revs->ignore_packed = NULL;
 865                                revs->num_ignore_packed = 0;
 866                                continue;
 867                        }
 868                        if (!strncmp(arg, "--unpacked=", 11)) {
 869                                revs->unpacked = 1;
 870                                add_ignore_packed(revs, arg+11);
 871                                continue;
 872                        }
 873                        if (!strcmp(arg, "-r")) {
 874                                revs->diff = 1;
 875                                revs->diffopt.recursive = 1;
 876                                continue;
 877                        }
 878                        if (!strcmp(arg, "-t")) {
 879                                revs->diff = 1;
 880                                revs->diffopt.recursive = 1;
 881                                revs->diffopt.tree_in_recursive = 1;
 882                                continue;
 883                        }
 884                        if (!strcmp(arg, "-m")) {
 885                                revs->ignore_merges = 0;
 886                                continue;
 887                        }
 888                        if (!strcmp(arg, "-c")) {
 889                                revs->diff = 1;
 890                                revs->dense_combined_merges = 0;
 891                                revs->combine_merges = 1;
 892                                continue;
 893                        }
 894                        if (!strcmp(arg, "--cc")) {
 895                                revs->diff = 1;
 896                                revs->dense_combined_merges = 1;
 897                                revs->combine_merges = 1;
 898                                continue;
 899                        }
 900                        if (!strcmp(arg, "-v")) {
 901                                revs->verbose_header = 1;
 902                                continue;
 903                        }
 904                        if (!strncmp(arg, "--pretty", 8)) {
 905                                revs->verbose_header = 1;
 906                                revs->commit_format = get_commit_format(arg+8);
 907                                continue;
 908                        }
 909                        if (!strcmp(arg, "--root")) {
 910                                revs->show_root_diff = 1;
 911                                continue;
 912                        }
 913                        if (!strcmp(arg, "--no-commit-id")) {
 914                                revs->no_commit_id = 1;
 915                                continue;
 916                        }
 917                        if (!strcmp(arg, "--always")) {
 918                                revs->always_show_header = 1;
 919                                continue;
 920                        }
 921                        if (!strcmp(arg, "--no-abbrev")) {
 922                                revs->abbrev = 0;
 923                                continue;
 924                        }
 925                        if (!strcmp(arg, "--abbrev")) {
 926                                revs->abbrev = DEFAULT_ABBREV;
 927                                continue;
 928                        }
 929                        if (!strncmp(arg, "--abbrev=", 9)) {
 930                                revs->abbrev = strtoul(arg + 9, NULL, 10);
 931                                if (revs->abbrev < MINIMUM_ABBREV)
 932                                        revs->abbrev = MINIMUM_ABBREV;
 933                                else if (revs->abbrev > 40)
 934                                        revs->abbrev = 40;
 935                                continue;
 936                        }
 937                        if (!strcmp(arg, "--abbrev-commit")) {
 938                                revs->abbrev_commit = 1;
 939                                continue;
 940                        }
 941                        if (!strcmp(arg, "--full-diff")) {
 942                                revs->diff = 1;
 943                                revs->full_diff = 1;
 944                                continue;
 945                        }
 946                        if (!strcmp(arg, "--full-history")) {
 947                                revs->simplify_history = 0;
 948                                continue;
 949                        }
 950                        if (!strcmp(arg, "--relative-date")) {
 951                                revs->relative_date = 1;
 952                                continue;
 953                        }
 954
 955                        /*
 956                         * Grepping the commit log
 957                         */
 958                        if (!strncmp(arg, "--author=", 9)) {
 959                                add_header_grep(revs, "author", arg+9);
 960                                continue;
 961                        }
 962                        if (!strncmp(arg, "--committer=", 12)) {
 963                                add_header_grep(revs, "committer", arg+12);
 964                                continue;
 965                        }
 966                        if (!strncmp(arg, "--grep=", 7)) {
 967                                add_message_grep(revs, arg+7);
 968                                continue;
 969                        }
 970
 971                        opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
 972                        if (opts > 0) {
 973                                revs->diff = 1;
 974                                i += opts - 1;
 975                                continue;
 976                        }
 977                        *unrecognized++ = arg;
 978                        left++;
 979                        continue;
 980                }
 981
 982                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
 983                        int j;
 984                        if (seen_dashdash || *arg == '^')
 985                                die("bad revision '%s'", arg);
 986
 987                        /* If we didn't have a "--":
 988                         * (1) all filenames must exist;
 989                         * (2) all rev-args must not be interpretable
 990                         *     as a valid filename.
 991                         * but the latter we have checked in the main loop.
 992                         */
 993                        for (j = i; j < argc; j++)
 994                                verify_filename(revs->prefix, argv[j]);
 995
 996                        revs->prune_data = get_pathspec(revs->prefix,
 997                                                        argv + i);
 998                        break;
 999                }
1000        }
1001
1002        if (show_merge)
1003                prepare_show_merge(revs);
1004        if (def && !revs->pending.nr) {
1005                unsigned char sha1[20];
1006                struct object *object;
1007                if (get_sha1(def, sha1))
1008                        die("bad default revision '%s'", def);
1009                object = get_reference(revs, def, sha1, 0);
1010                add_pending_object(revs, object, def);
1011        }
1012
1013        if (revs->topo_order || revs->unpacked)
1014                revs->limited = 1;
1015
1016        if (revs->prune_data) {
1017                diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1018                revs->prune_fn = try_to_simplify_commit;
1019                if (!revs->full_diff)
1020                        diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1021        }
1022        if (revs->combine_merges) {
1023                revs->ignore_merges = 0;
1024                if (revs->dense_combined_merges && !revs->diffopt.output_format)
1025                        revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1026        }
1027        revs->diffopt.abbrev = revs->abbrev;
1028        if (diff_setup_done(&revs->diffopt) < 0)
1029                die("diff_setup_done failed");
1030
1031        if (revs->grep_filter)
1032                compile_grep_patterns(revs->grep_filter);
1033
1034        return left;
1035}
1036
1037void prepare_revision_walk(struct rev_info *revs)
1038{
1039        int nr = revs->pending.nr;
1040        struct object_array_entry *list = revs->pending.objects;
1041
1042        revs->pending.nr = 0;
1043        revs->pending.alloc = 0;
1044        revs->pending.objects = NULL;
1045        while (--nr >= 0) {
1046                struct commit *commit = handle_commit(revs, list->item, list->name);
1047                if (commit) {
1048                        if (!(commit->object.flags & SEEN)) {
1049                                commit->object.flags |= SEEN;
1050                                insert_by_date(commit, &revs->commits);
1051                        }
1052                }
1053                list++;
1054        }
1055
1056        if (revs->no_walk)
1057                return;
1058        if (revs->limited)
1059                limit_list(revs);
1060        if (revs->topo_order)
1061                sort_in_topological_order_fn(&revs->commits, revs->lifo,
1062                                             revs->topo_setter,
1063                                             revs->topo_getter);
1064}
1065
1066static int rewrite_one(struct rev_info *revs, struct commit **pp)
1067{
1068        for (;;) {
1069                struct commit *p = *pp;
1070                if (!revs->limited)
1071                        add_parents_to_list(revs, p, &revs->commits);
1072                if (p->parents && p->parents->next)
1073                        return 0;
1074                if (p->object.flags & (TREECHANGE | UNINTERESTING))
1075                        return 0;
1076                if (!p->parents)
1077                        return -1;
1078                *pp = p->parents->item;
1079        }
1080}
1081
1082static void rewrite_parents(struct rev_info *revs, struct commit *commit)
1083{
1084        struct commit_list **pp = &commit->parents;
1085        while (*pp) {
1086                struct commit_list *parent = *pp;
1087                if (rewrite_one(revs, &parent->item) < 0) {
1088                        *pp = parent->next;
1089                        continue;
1090                }
1091                pp = &parent->next;
1092        }
1093}
1094
1095static void mark_boundary_to_show(struct commit *commit)
1096{
1097        struct commit_list *p = commit->parents;
1098        while (p) {
1099                commit = p->item;
1100                p = p->next;
1101                if (commit->object.flags & BOUNDARY)
1102                        commit->object.flags |= BOUNDARY_SHOW;
1103        }
1104}
1105
1106static int commit_match(struct commit *commit, struct rev_info *opt)
1107{
1108        if (!opt->grep_filter)
1109                return 1;
1110        return grep_buffer(opt->grep_filter,
1111                           NULL, /* we say nothing, not even filename */
1112                           commit->buffer, strlen(commit->buffer));
1113}
1114
1115struct commit *get_revision(struct rev_info *revs)
1116{
1117        struct commit_list *list = revs->commits;
1118
1119        if (!list)
1120                return NULL;
1121
1122        /* Check the max_count ... */
1123        switch (revs->max_count) {
1124        case -1:
1125                break;
1126        case 0:
1127                return NULL;
1128        default:
1129                revs->max_count--;
1130        }
1131
1132        do {
1133                struct commit_list *entry = revs->commits;
1134                struct commit *commit = entry->item;
1135
1136                revs->commits = entry->next;
1137                free(entry);
1138
1139                /*
1140                 * If we haven't done the list limiting, we need to look at
1141                 * the parents here. We also need to do the date-based limiting
1142                 * that we'd otherwise have done in limit_list().
1143                 */
1144                if (!revs->limited) {
1145                        if ((revs->unpacked &&
1146                             has_sha1_pack(commit->object.sha1,
1147                                           revs->ignore_packed)) ||
1148                            (revs->max_age != -1 &&
1149                             (commit->date < revs->max_age)))
1150                                continue;
1151                        add_parents_to_list(revs, commit, &revs->commits);
1152                }
1153                if (commit->object.flags & SHOWN)
1154                        continue;
1155
1156                /* We want to show boundary commits only when their
1157                 * children are shown.  When path-limiter is in effect,
1158                 * rewrite_parents() drops some commits from getting shown,
1159                 * and there is no point showing boundary parents that
1160                 * are not shown.  After rewrite_parents() rewrites the
1161                 * parents of a commit that is shown, we mark the boundary
1162                 * parents with BOUNDARY_SHOW.
1163                 */
1164                if (commit->object.flags & BOUNDARY_SHOW) {
1165                        commit->object.flags |= SHOWN;
1166                        return commit;
1167                }
1168                if (commit->object.flags & UNINTERESTING)
1169                        continue;
1170                if (revs->min_age != -1 && (commit->date > revs->min_age))
1171                        continue;
1172                if (revs->no_merges &&
1173                    commit->parents && commit->parents->next)
1174                        continue;
1175                if (!commit_match(commit, revs))
1176                        continue;
1177                if (revs->prune_fn && revs->dense) {
1178                        /* Commit without changes? */
1179                        if (!(commit->object.flags & TREECHANGE)) {
1180                                /* drop merges unless we want parenthood */
1181                                if (!revs->parents)
1182                                        continue;
1183                                /* non-merge - always ignore it */
1184                                if (!commit->parents || !commit->parents->next)
1185                                        continue;
1186                        }
1187                        if (revs->parents)
1188                                rewrite_parents(revs, commit);
1189                }
1190                if (revs->boundary)
1191                        mark_boundary_to_show(commit);
1192                commit->object.flags |= SHOWN;
1193                return commit;
1194        } while (revs->commits);
1195        return NULL;
1196}