rev-list.con commit git-upload-pack: More efficient usage of the has_sha1 array (794f9fe)
   1#include "cache.h"
   2#include "refs.h"
   3#include "tag.h"
   4#include "commit.h"
   5#include "tree.h"
   6#include "blob.h"
   7#include "epoch.h"
   8#include "diff.h"
   9
  10#define SEEN            (1u << 0)
  11#define INTERESTING     (1u << 1)
  12#define COUNTED         (1u << 2)
  13#define SHOWN           (1u << 3)
  14#define TREECHANGE      (1u << 4)
  15
  16static const char rev_list_usage[] =
  17        "git-rev-list [OPTION] commit-id <commit-id>\n"
  18                      "  --max-count=nr\n"
  19                      "  --max-age=epoch\n"
  20                      "  --min-age=epoch\n"
  21                      "  --parents\n"
  22                      "  --bisect\n"
  23                      "  --objects\n"
  24                      "  --unpacked\n"
  25                      "  --header\n"
  26                      "  --pretty\n"
  27                      "  --no-merges\n"
  28                      "  --merge-order [ --show-breaks ]\n"
  29                      "  --topo-order";
  30
  31static int dense = 0;
  32static int unpacked = 0;
  33static int bisect_list = 0;
  34static int tag_objects = 0;
  35static int tree_objects = 0;
  36static int blob_objects = 0;
  37static int verbose_header = 0;
  38static int show_parents = 0;
  39static int hdr_termination = 0;
  40static const char *commit_prefix = "";
  41static unsigned long max_age = -1;
  42static unsigned long min_age = -1;
  43static int max_count = -1;
  44static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  45static int merge_order = 0;
  46static int show_breaks = 0;
  47static int stop_traversal = 0;
  48static int topo_order = 0;
  49static int no_merges = 0;
  50static const char **paths = NULL;
  51
  52static void show_commit(struct commit *commit)
  53{
  54        commit->object.flags |= SHOWN;
  55        if (show_breaks) {
  56                commit_prefix = "| ";
  57                if (commit->object.flags & DISCONTINUITY) {
  58                        commit_prefix = "^ ";     
  59                } else if (commit->object.flags & BOUNDARY) {
  60                        commit_prefix = "= ";
  61                } 
  62        }                       
  63        printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
  64        if (show_parents) {
  65                struct commit_list *parents = commit->parents;
  66                while (parents) {
  67                        printf(" %s", sha1_to_hex(parents->item->object.sha1));
  68                        parents = parents->next;
  69                }
  70        }
  71        if (commit_format == CMIT_FMT_ONELINE)
  72                putchar(' ');
  73        else
  74                putchar('\n');
  75
  76        if (verbose_header) {
  77                static char pretty_header[16384];
  78                pretty_print_commit(commit_format, commit->buffer, ~0, pretty_header, sizeof(pretty_header));
  79                printf("%s%c", pretty_header, hdr_termination);
  80        }
  81        fflush(stdout);
  82}
  83
  84static void rewrite_one(struct commit **pp)
  85{
  86        for (;;) {
  87                struct commit *p = *pp;
  88                if (p->object.flags & (TREECHANGE | UNINTERESTING))
  89                        return;
  90                /* Only single-parent commits don't have TREECHANGE */
  91                *pp = p->parents->item;
  92        }
  93}
  94
  95static void rewrite_parents(struct commit *commit)
  96{
  97        struct commit_list *parent = commit->parents;
  98        while (parent) {
  99                rewrite_one(&parent->item);
 100                parent = parent->next;
 101        }
 102}
 103
 104static int filter_commit(struct commit * commit)
 105{
 106        if (stop_traversal && (commit->object.flags & BOUNDARY))
 107                return STOP;
 108        if (commit->object.flags & (UNINTERESTING|SHOWN))
 109                return CONTINUE;
 110        if (min_age != -1 && (commit->date > min_age))
 111                return CONTINUE;
 112        if (max_age != -1 && (commit->date < max_age)) {
 113                stop_traversal=1;
 114                return CONTINUE;
 115        }
 116        if (max_count != -1 && !max_count--)
 117                return STOP;
 118        if (no_merges && (commit->parents && commit->parents->next))
 119                return CONTINUE;
 120        if (paths && dense) {
 121                if (!(commit->object.flags & TREECHANGE))
 122                        return CONTINUE;
 123                rewrite_parents(commit);
 124        }
 125        return DO;
 126}
 127
 128static int process_commit(struct commit * commit)
 129{
 130        int action=filter_commit(commit);
 131
 132        if (action == STOP) {
 133                return STOP;
 134        }
 135
 136        if (action == CONTINUE) {
 137                return CONTINUE;
 138        }
 139
 140        show_commit(commit);
 141
 142        return CONTINUE;
 143}
 144
 145static struct object_list **add_object(struct object *obj, struct object_list **p, const char *name)
 146{
 147        struct object_list *entry = xmalloc(sizeof(*entry));
 148        entry->item = obj;
 149        entry->next = *p;
 150        entry->name = name;
 151        *p = entry;
 152        return &entry->next;
 153}
 154
 155static struct object_list **process_blob(struct blob *blob, struct object_list **p, const char *name)
 156{
 157        struct object *obj = &blob->object;
 158
 159        if (!blob_objects)
 160                return p;
 161        if (obj->flags & (UNINTERESTING | SEEN))
 162                return p;
 163        obj->flags |= SEEN;
 164        return add_object(obj, p, name);
 165}
 166
 167static struct object_list **process_tree(struct tree *tree, struct object_list **p, const char *name)
 168{
 169        struct object *obj = &tree->object;
 170        struct tree_entry_list *entry;
 171
 172        if (!tree_objects)
 173                return p;
 174        if (obj->flags & (UNINTERESTING | SEEN))
 175                return p;
 176        if (parse_tree(tree) < 0)
 177                die("bad tree object %s", sha1_to_hex(obj->sha1));
 178        obj->flags |= SEEN;
 179        p = add_object(obj, p, name);
 180        entry = tree->entries;
 181        tree->entries = NULL;
 182        while (entry) {
 183                struct tree_entry_list *next = entry->next;
 184                if (entry->directory)
 185                        p = process_tree(entry->item.tree, p, entry->name);
 186                else
 187                        p = process_blob(entry->item.blob, p, entry->name);
 188                free(entry);
 189                entry = next;
 190        }
 191        return p;
 192}
 193
 194static struct object_list *pending_objects = NULL;
 195
 196static void show_commit_list(struct commit_list *list)
 197{
 198        struct object_list *objects = NULL, **p = &objects, *pending;
 199        while (list) {
 200                struct commit *commit = pop_most_recent_commit(&list, SEEN);
 201
 202                p = process_tree(commit->tree, p, "");
 203                if (process_commit(commit) == STOP)
 204                        break;
 205        }
 206        for (pending = pending_objects; pending; pending = pending->next) {
 207                struct object *obj = pending->item;
 208                const char *name = pending->name;
 209                if (obj->flags & (UNINTERESTING | SEEN))
 210                        continue;
 211                if (obj->type == tag_type) {
 212                        obj->flags |= SEEN;
 213                        p = add_object(obj, p, name);
 214                        continue;
 215                }
 216                if (obj->type == tree_type) {
 217                        p = process_tree((struct tree *)obj, p, name);
 218                        continue;
 219                }
 220                if (obj->type == blob_type) {
 221                        p = process_blob((struct blob *)obj, p, name);
 222                        continue;
 223                }
 224                die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 225        }
 226        while (objects) {
 227                /* An object with name "foo\n0000000000000000000000000000000000000000"
 228                 * can be used confuse downstream git-pack-objects very badly.
 229                 */
 230                const char *ep = strchr(objects->name, '\n');
 231                if (ep) {
 232                        printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 233                               (int) (ep - objects->name),
 234                               objects->name);
 235                }
 236                else
 237                        printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 238                objects = objects->next;
 239        }
 240}
 241
 242static void mark_blob_uninteresting(struct blob *blob)
 243{
 244        if (!blob_objects)
 245                return;
 246        if (blob->object.flags & UNINTERESTING)
 247                return;
 248        blob->object.flags |= UNINTERESTING;
 249}
 250
 251static void mark_tree_uninteresting(struct tree *tree)
 252{
 253        struct object *obj = &tree->object;
 254        struct tree_entry_list *entry;
 255
 256        if (!tree_objects)
 257                return;
 258        if (obj->flags & UNINTERESTING)
 259                return;
 260        obj->flags |= UNINTERESTING;
 261        if (!has_sha1_file(obj->sha1))
 262                return;
 263        if (parse_tree(tree) < 0)
 264                die("bad tree %s", sha1_to_hex(obj->sha1));
 265        entry = tree->entries;
 266        tree->entries = NULL;
 267        while (entry) {
 268                struct tree_entry_list *next = entry->next;
 269                if (entry->directory)
 270                        mark_tree_uninteresting(entry->item.tree);
 271                else
 272                        mark_blob_uninteresting(entry->item.blob);
 273                free(entry);
 274                entry = next;
 275        }
 276}
 277
 278static void mark_parents_uninteresting(struct commit *commit)
 279{
 280        struct commit_list *parents = commit->parents;
 281
 282        while (parents) {
 283                struct commit *commit = parents->item;
 284                commit->object.flags |= UNINTERESTING;
 285
 286                /*
 287                 * Normally we haven't parsed the parent
 288                 * yet, so we won't have a parent of a parent
 289                 * here. However, it may turn out that we've
 290                 * reached this commit some other way (where it
 291                 * wasn't uninteresting), in which case we need
 292                 * to mark its parents recursively too..
 293                 */
 294                if (commit->parents)
 295                        mark_parents_uninteresting(commit);
 296
 297                /*
 298                 * A missing commit is ok iff its parent is marked 
 299                 * uninteresting.
 300                 *
 301                 * We just mark such a thing parsed, so that when
 302                 * it is popped next time around, we won't be trying
 303                 * to parse it and get an error.
 304                 */
 305                if (!has_sha1_file(commit->object.sha1))
 306                        commit->object.parsed = 1;
 307                parents = parents->next;
 308        }
 309}
 310
 311static int everybody_uninteresting(struct commit_list *orig)
 312{
 313        struct commit_list *list = orig;
 314        while (list) {
 315                struct commit *commit = list->item;
 316                list = list->next;
 317                if (commit->object.flags & UNINTERESTING)
 318                        continue;
 319                return 0;
 320        }
 321        return 1;
 322}
 323
 324/*
 325 * This is a truly stupid algorithm, but it's only
 326 * used for bisection, and we just don't care enough.
 327 *
 328 * We care just barely enough to avoid recursing for
 329 * non-merge entries.
 330 */
 331static int count_distance(struct commit_list *entry)
 332{
 333        int nr = 0;
 334
 335        while (entry) {
 336                struct commit *commit = entry->item;
 337                struct commit_list *p;
 338
 339                if (commit->object.flags & (UNINTERESTING | COUNTED))
 340                        break;
 341                nr++;
 342                commit->object.flags |= COUNTED;
 343                p = commit->parents;
 344                entry = p;
 345                if (p) {
 346                        p = p->next;
 347                        while (p) {
 348                                nr += count_distance(p);
 349                                p = p->next;
 350                        }
 351                }
 352        }
 353        return nr;
 354}
 355
 356static void clear_distance(struct commit_list *list)
 357{
 358        while (list) {
 359                struct commit *commit = list->item;
 360                commit->object.flags &= ~COUNTED;
 361                list = list->next;
 362        }
 363}
 364
 365static struct commit_list *find_bisection(struct commit_list *list)
 366{
 367        int nr, closest;
 368        struct commit_list *p, *best;
 369
 370        nr = 0;
 371        p = list;
 372        while (p) {
 373                nr++;
 374                p = p->next;
 375        }
 376        closest = 0;
 377        best = list;
 378
 379        p = list;
 380        while (p) {
 381                int distance = count_distance(p);
 382                clear_distance(list);
 383                if (nr - distance < distance)
 384                        distance = nr - distance;
 385                if (distance > closest) {
 386                        best = p;
 387                        closest = distance;
 388                }
 389                p = p->next;
 390        }
 391        if (best)
 392                best->next = NULL;
 393        return best;
 394}
 395
 396static void mark_edges_uninteresting(struct commit_list *list)
 397{
 398        for ( ; list; list = list->next) {
 399                struct commit_list *parents = list->item->parents;
 400
 401                for ( ; parents; parents = parents->next) {
 402                        struct commit *commit = parents->item;
 403                        if (commit->object.flags & UNINTERESTING)
 404                                mark_tree_uninteresting(commit->tree);
 405                }
 406        }
 407}
 408
 409static int is_different = 0;
 410
 411static void file_add_remove(struct diff_options *options,
 412                    int addremove, unsigned mode,
 413                    const unsigned char *sha1,
 414                    const char *base, const char *path)
 415{
 416        is_different = 1;
 417}
 418
 419static void file_change(struct diff_options *options,
 420                 unsigned old_mode, unsigned new_mode,
 421                 const unsigned char *old_sha1,
 422                 const unsigned char *new_sha1,
 423                 const char *base, const char *path)
 424{
 425        is_different = 1;
 426}
 427
 428static struct diff_options diff_opt = {
 429        .recursive = 1,
 430        .add_remove = file_add_remove,
 431        .change = file_change,
 432};
 433
 434static int same_tree(struct tree *t1, struct tree *t2)
 435{
 436        is_different = 0;
 437        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 438                return 0;
 439        return !is_different;
 440}
 441
 442static struct commit *try_to_simplify_merge(struct commit *commit, struct commit_list *parent)
 443{
 444        if (!commit->tree)
 445                return NULL;
 446
 447        while (parent) {
 448                struct commit *p = parent->item;
 449                parent = parent->next;
 450                parse_commit(p);
 451                if (!p->tree)
 452                        continue;
 453                if (same_tree(commit->tree, p->tree))
 454                        return p;
 455        }
 456        return NULL;
 457}
 458
 459static void add_parents_to_list(struct commit *commit, struct commit_list **list)
 460{
 461        struct commit_list *parent = commit->parents;
 462
 463        /*
 464         * If the commit is uninteresting, don't try to
 465         * prune parents - we want the maximal uninteresting
 466         * set.
 467         *
 468         * Normally we haven't parsed the parent
 469         * yet, so we won't have a parent of a parent
 470         * here. However, it may turn out that we've
 471         * reached this commit some other way (where it
 472         * wasn't uninteresting), in which case we need
 473         * to mark its parents recursively too..
 474         */
 475        if (commit->object.flags & UNINTERESTING) {
 476                while (parent) {
 477                        struct commit *p = parent->item;
 478                        parent = parent->next;
 479                        parse_commit(p);
 480                        p->object.flags |= UNINTERESTING;
 481                        if (p->parents)
 482                                mark_parents_uninteresting(p);
 483                        if (p->object.flags & SEEN)
 484                                continue;
 485                        p->object.flags |= SEEN;
 486                        insert_by_date(p, list);
 487                }
 488                return;
 489        }
 490
 491        /*
 492         * Ok, the commit wasn't uninteresting. If it
 493         * is a merge, try to find the parent that has
 494         * no differences in the path set if one exists.
 495         */
 496        if (paths && parent && parent->next) {
 497                struct commit *preferred;
 498
 499                preferred = try_to_simplify_merge(commit, parent);
 500                if (preferred) {
 501                        parent->item = preferred;
 502                        parent->next = NULL;
 503                }
 504        }
 505
 506        while (parent) {
 507                struct commit *p = parent->item;
 508
 509                parent = parent->next;
 510
 511                parse_commit(p);
 512                if (p->object.flags & SEEN)
 513                        continue;
 514                p->object.flags |= SEEN;
 515                insert_by_date(p, list);
 516        }
 517}
 518
 519static void compress_list(struct commit_list *list)
 520{
 521        while (list) {
 522                struct commit *commit = list->item;
 523                struct commit_list *parent = commit->parents;
 524                list = list->next;
 525
 526                /*
 527                 * Exactly one parent? Check if it leaves the tree
 528                 * unchanged
 529                 */
 530                if (parent && !parent->next) {
 531                        struct tree *t1 = commit->tree;
 532                        struct tree *t2 = parent->item->tree;
 533                        if (!t1 || !t2 || same_tree(t1, t2))
 534                                continue;
 535                }
 536                commit->object.flags |= TREECHANGE;
 537        }
 538}
 539
 540static struct commit_list *limit_list(struct commit_list *list)
 541{
 542        struct commit_list *newlist = NULL;
 543        struct commit_list **p = &newlist;
 544        while (list) {
 545                struct commit_list *entry = list;
 546                struct commit *commit = list->item;
 547                struct object *obj = &commit->object;
 548
 549                list = list->next;
 550                free(entry);
 551
 552                if (max_age != -1 && (commit->date < max_age))
 553                        obj->flags |= UNINTERESTING;
 554                if (unpacked && has_sha1_pack(obj->sha1))
 555                        obj->flags |= UNINTERESTING;
 556                add_parents_to_list(commit, &list);
 557                if (obj->flags & UNINTERESTING) {
 558                        mark_parents_uninteresting(commit);
 559                        if (everybody_uninteresting(list))
 560                                break;
 561                        continue;
 562                }
 563                if (min_age != -1 && (commit->date > min_age))
 564                        continue;
 565                p = &commit_list_insert(commit, p)->next;
 566        }
 567        if (tree_objects)
 568                mark_edges_uninteresting(newlist);
 569        if (paths && dense)
 570                compress_list(newlist);
 571        if (bisect_list)
 572                newlist = find_bisection(newlist);
 573        return newlist;
 574}
 575
 576static void add_pending_object(struct object *obj, const char *name)
 577{
 578        add_object(obj, &pending_objects, name);
 579}
 580
 581static struct commit *get_commit_reference(const char *name, unsigned int flags)
 582{
 583        unsigned char sha1[20];
 584        struct object *object;
 585
 586        if (get_sha1(name, sha1))
 587                usage(rev_list_usage);
 588        object = parse_object(sha1);
 589        if (!object)
 590                die("bad object %s", name);
 591
 592        /*
 593         * Tag object? Look what it points to..
 594         */
 595        while (object->type == tag_type) {
 596                struct tag *tag = (struct tag *) object;
 597                object->flags |= flags;
 598                if (tag_objects && !(object->flags & UNINTERESTING))
 599                        add_pending_object(object, tag->tag);
 600                object = parse_object(tag->tagged->sha1);
 601                if (!object)
 602                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 603        }
 604
 605        /*
 606         * Commit object? Just return it, we'll do all the complex
 607         * reachability crud.
 608         */
 609        if (object->type == commit_type) {
 610                struct commit *commit = (struct commit *)object;
 611                object->flags |= flags;
 612                if (parse_commit(commit) < 0)
 613                        die("unable to parse commit %s", name);
 614                if (flags & UNINTERESTING)
 615                        mark_parents_uninteresting(commit);
 616                return commit;
 617        }
 618
 619        /*
 620         * Tree object? Either mark it uniniteresting, or add it
 621         * to the list of objects to look at later..
 622         */
 623        if (object->type == tree_type) {
 624                struct tree *tree = (struct tree *)object;
 625                if (!tree_objects)
 626                        return NULL;
 627                if (flags & UNINTERESTING) {
 628                        mark_tree_uninteresting(tree);
 629                        return NULL;
 630                }
 631                add_pending_object(object, "");
 632                return NULL;
 633        }
 634
 635        /*
 636         * Blob object? You know the drill by now..
 637         */
 638        if (object->type == blob_type) {
 639                struct blob *blob = (struct blob *)object;
 640                if (!blob_objects)
 641                        return NULL;
 642                if (flags & UNINTERESTING) {
 643                        mark_blob_uninteresting(blob);
 644                        return NULL;
 645                }
 646                add_pending_object(object, "");
 647                return NULL;
 648        }
 649        die("%s is unknown object", name);
 650}
 651
 652static void handle_one_commit(struct commit *com, struct commit_list **lst)
 653{
 654        if (!com || com->object.flags & SEEN)
 655                return;
 656        com->object.flags |= SEEN;
 657        commit_list_insert(com, lst);
 658}
 659
 660/* for_each_ref() callback does not allow user data -- Yuck. */
 661static struct commit_list **global_lst;
 662
 663static int include_one_commit(const char *path, const unsigned char *sha1)
 664{
 665        struct commit *com = get_commit_reference(path, 0);
 666        handle_one_commit(com, global_lst);
 667        return 0;
 668}
 669
 670static void handle_all(struct commit_list **lst)
 671{
 672        global_lst = lst;
 673        for_each_ref(include_one_commit);
 674        global_lst = NULL;
 675}
 676
 677int main(int argc, const char **argv)
 678{
 679        const char *prefix = setup_git_directory();
 680        struct commit_list *list = NULL;
 681        int i, limited = 0;
 682
 683        for (i = 1 ; i < argc; i++) {
 684                int flags;
 685                const char *arg = argv[i];
 686                char *dotdot;
 687                struct commit *commit;
 688
 689                if (!strncmp(arg, "--max-count=", 12)) {
 690                        max_count = atoi(arg + 12);
 691                        continue;
 692                }
 693                if (!strncmp(arg, "--max-age=", 10)) {
 694                        max_age = atoi(arg + 10);
 695                        limited = 1;
 696                        continue;
 697                }
 698                if (!strncmp(arg, "--min-age=", 10)) {
 699                        min_age = atoi(arg + 10);
 700                        limited = 1;
 701                        continue;
 702                }
 703                if (!strcmp(arg, "--header")) {
 704                        verbose_header = 1;
 705                        continue;
 706                }
 707                if (!strncmp(arg, "--pretty", 8)) {
 708                        commit_format = get_commit_format(arg+8);
 709                        verbose_header = 1;
 710                        hdr_termination = '\n';
 711                        if (commit_format == CMIT_FMT_ONELINE)
 712                                commit_prefix = "";
 713                        else
 714                                commit_prefix = "commit ";
 715                        continue;
 716                }
 717                if (!strncmp(arg, "--no-merges", 11)) {
 718                        no_merges = 1;
 719                        continue;
 720                }
 721                if (!strcmp(arg, "--parents")) {
 722                        show_parents = 1;
 723                        continue;
 724                }
 725                if (!strcmp(arg, "--bisect")) {
 726                        bisect_list = 1;
 727                        continue;
 728                }
 729                if (!strcmp(arg, "--all")) {
 730                        handle_all(&list);
 731                        continue;
 732                }
 733                if (!strcmp(arg, "--objects")) {
 734                        tag_objects = 1;
 735                        tree_objects = 1;
 736                        blob_objects = 1;
 737                        continue;
 738                }
 739                if (!strcmp(arg, "--unpacked")) {
 740                        unpacked = 1;
 741                        limited = 1;
 742                        continue;
 743                }
 744                if (!strcmp(arg, "--merge-order")) {
 745                        merge_order = 1;
 746                        continue;
 747                }
 748                if (!strcmp(arg, "--show-breaks")) {
 749                        show_breaks = 1;
 750                        continue;
 751                }
 752                if (!strcmp(arg, "--topo-order")) {
 753                        topo_order = 1;
 754                        limited = 1;
 755                        continue;
 756                }
 757                if (!strcmp(arg, "--dense")) {
 758                        dense = 1;
 759                        continue;
 760                }
 761                if (!strcmp(arg, "--")) {
 762                        paths = get_pathspec(prefix, argv + i + 1);
 763                        if (paths) {
 764                                limited = 1;
 765                                diff_tree_setup_paths(paths);
 766                        }
 767                        break;
 768                }
 769
 770                if (show_breaks && !merge_order)
 771                        usage(rev_list_usage);
 772
 773                flags = 0;
 774                dotdot = strstr(arg, "..");
 775                if (dotdot) {
 776                        char *next = dotdot + 2;
 777                        struct commit *exclude = NULL;
 778                        struct commit *include = NULL;
 779                        *dotdot = 0;
 780                        if (!*next)
 781                                next = "HEAD";
 782                        exclude = get_commit_reference(arg, UNINTERESTING);
 783                        include = get_commit_reference(next, 0);
 784                        if (exclude && include) {
 785                                limited = 1;
 786                                handle_one_commit(exclude, &list);
 787                                handle_one_commit(include, &list);
 788                                continue;
 789                        }
 790                        *dotdot = '.';
 791                }
 792                if (*arg == '^') {
 793                        flags = UNINTERESTING;
 794                        arg++;
 795                        limited = 1;
 796                }
 797                commit = get_commit_reference(arg, flags);
 798                handle_one_commit(commit, &list);
 799        }
 800
 801        save_commit_buffer = verbose_header;
 802        track_object_refs = 0;
 803
 804        if (!merge_order) {             
 805                sort_by_date(&list);
 806                if (list && !limited && max_count == 1 &&
 807                    !tag_objects && !tree_objects && !blob_objects) {
 808                        show_commit(list->item);
 809                        return 0;
 810                }
 811                if (limited)
 812                        list = limit_list(list);
 813                if (topo_order)
 814                        sort_in_topological_order(&list);
 815                show_commit_list(list);
 816        } else {
 817#ifndef NO_OPENSSL
 818                if (sort_list_in_merge_order(list, &process_commit)) {
 819                        die("merge order sort failed\n");
 820                }
 821#else
 822                die("merge order sort unsupported, OpenSSL not linked");
 823#endif
 824        }
 825
 826        return 0;
 827}