rev-list.c

   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
  16 static 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
  31 static int dense = 1;
  32 static int unpacked = 0;
  33 static int bisect_list = 0;
  34 static int tag_objects = 0;
  35 static int tree_objects = 0;
  36 static int blob_objects = 0;
  37 static int verbose_header = 0;
  38 static int show_parents = 0;
  39 static int hdr_termination = 0;
  40 static const char *commit_prefix = "";
  41 static unsigned long max_age = -1;
  42 static unsigned long min_age = -1;
  43 static int max_count = -1;
  44 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  45 static int merge_order = 0;
  46 static int show_breaks = 0;
  47 static int stop_traversal = 0;
  48 static int topo_order = 0;
  49 static int no_merges = 0;
  50 static const char **paths = NULL;
  51
  52 static 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
  84 static int rewrite_one(struct commit **pp)
  85 {
  86         for (;;) {
  87                 struct commit *p = *pp;
  88                 if (p->object.flags & (TREECHANGE | UNINTERESTING))
  89                         return 0;
  90                 if (!p->parents)
  91                         return -1;
  92                 *pp = p->parents->item;
  93         }
  94 }
  95
  96 static void rewrite_parents(struct commit *commit)
  97 {
  98         struct commit_list **pp = &commit->parents;
  99         while (*pp) {
 100                 struct commit_list *parent = *pp;
 101                 if (rewrite_one(&parent->item) < 0) {
 102                         *pp = parent->next;
 103                         continue;
 104                 }
 105                 pp = &parent->next;
 106         }
 107 }
 108
 109 static int filter_commit(struct commit * commit)
 110 {
 111         if (stop_traversal && (commit->object.flags & BOUNDARY))
 112                 return STOP;
 113         if (commit->object.flags & (UNINTERESTING|SHOWN))
 114                 return CONTINUE;
 115         if (min_age != -1 && (commit->date > min_age))
 116                 return CONTINUE;
 117         if (max_age != -1 && (commit->date < max_age)) {
 118                 stop_traversal=1;
 119                 return CONTINUE;
 120         }
 121         if (max_count != -1 && !max_count--)
 122                 return STOP;
 123         if (no_merges && (commit->parents && commit->parents->next))
 124                 return CONTINUE;
 125         if (paths && dense) {
 126                 if (!(commit->object.flags & TREECHANGE))
 127                         return CONTINUE;
 128                 rewrite_parents(commit);
 129         }
 130         return DO;
 131 }
 132
 133 static int process_commit(struct commit * commit)
 134 {
 135         int action=filter_commit(commit);
 136
 137         if (action == STOP) {
 138                 return STOP;
 139         }
 140
 141         if (action == CONTINUE) {
 142                 return CONTINUE;
 143         }
 144
 145         show_commit(commit);
 146
 147         return CONTINUE;
 148 }
 149
 150 static struct object_list **add_object(struct object *obj, struct object_list **p, const char *name)
 151 {
 152         struct object_list *entry = xmalloc(sizeof(*entry));
 153         entry->item = obj;
 154         entry->next = *p;
 155         entry->name = name;
 156         *p = entry;
 157         return &entry->next;
 158 }
 159
 160 static struct object_list **process_blob(struct blob *blob, struct object_list **p, const char *name)
 161 {
 162         struct object *obj = &blob->object;
 163
 164         if (!blob_objects)
 165                 return p;
 166         if (obj->flags & (UNINTERESTING | SEEN))
 167                 return p;
 168         obj->flags |= SEEN;
 169         return add_object(obj, p, name);
 170 }
 171
 172 static struct object_list **process_tree(struct tree *tree, struct object_list **p, const char *name)
 173 {
 174         struct object *obj = &tree->object;
 175         struct tree_entry_list *entry;
 176
 177         if (!tree_objects)
 178                 return p;
 179         if (obj->flags & (UNINTERESTING | SEEN))
 180                 return p;
 181         if (parse_tree(tree) < 0)
 182                 die("bad tree object %s", sha1_to_hex(obj->sha1));
 183         obj->flags |= SEEN;
 184         p = add_object(obj, p, name);
 185         entry = tree->entries;
 186         tree->entries = NULL;
 187         while (entry) {
 188                 struct tree_entry_list *next = entry->next;
 189                 if (entry->directory)
 190                         p = process_tree(entry->item.tree, p, entry->name);
 191                 else
 192                         p = process_blob(entry->item.blob, p, entry->name);
 193                 free(entry);
 194                 entry = next;
 195         }
 196         return p;
 197 }
 198
 199 static struct object_list *pending_objects = NULL;
 200
 201 static void show_commit_list(struct commit_list *list)
 202 {
 203         struct object_list *objects = NULL, **p = &objects, *pending;
 204         while (list) {
 205                 struct commit *commit = pop_most_recent_commit(&list, SEEN);
 206
 207                 p = process_tree(commit->tree, p, "");
 208                 if (process_commit(commit) == STOP)
 209                         break;
 210         }
 211         for (pending = pending_objects; pending; pending = pending->next) {
 212                 struct object *obj = pending->item;
 213                 const char *name = pending->name;
 214                 if (obj->flags & (UNINTERESTING | SEEN))
 215                         continue;
 216                 if (obj->type == tag_type) {
 217                         obj->flags |= SEEN;
 218                         p = add_object(obj, p, name);
 219                         continue;
 220                 }
 221                 if (obj->type == tree_type) {
 222                         p = process_tree((struct tree *)obj, p, name);
 223                         continue;
 224                 }
 225                 if (obj->type == blob_type) {
 226                         p = process_blob((struct blob *)obj, p, name);
 227                         continue;
 228                 }
 229                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 230         }
 231         while (objects) {
 232                 /* An object with name "foo\n0000000000000000000000000000000000000000"
 233                  * can be used confuse downstream git-pack-objects very badly.
 234                  */
 235                 const char *ep = strchr(objects->name, '\n');
 236                 if (ep) {
 237                         printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 238                                (int) (ep - objects->name),
 239                                objects->name);
 240                 }
 241                 else
 242                         printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 243                 objects = objects->next;
 244         }
 245 }
 246
 247 static void mark_blob_uninteresting(struct blob *blob)
 248 {
 249         if (!blob_objects)
 250                 return;
 251         if (blob->object.flags & UNINTERESTING)
 252                 return;
 253         blob->object.flags |= UNINTERESTING;
 254 }
 255
 256 static void mark_tree_uninteresting(struct tree *tree)
 257 {
 258         struct object *obj = &tree->object;
 259         struct tree_entry_list *entry;
 260
 261         if (!tree_objects)
 262                 return;
 263         if (obj->flags & UNINTERESTING)
 264                 return;
 265         obj->flags |= UNINTERESTING;
 266         if (!has_sha1_file(obj->sha1))
 267                 return;
 268         if (parse_tree(tree) < 0)
 269                 die("bad tree %s", sha1_to_hex(obj->sha1));
 270         entry = tree->entries;
 271         tree->entries = NULL;
 272         while (entry) {
 273                 struct tree_entry_list *next = entry->next;
 274                 if (entry->directory)
 275                         mark_tree_uninteresting(entry->item.tree);
 276                 else
 277                         mark_blob_uninteresting(entry->item.blob);
 278                 free(entry);
 279                 entry = next;
 280         }
 281 }
 282
 283 static void mark_parents_uninteresting(struct commit *commit)
 284 {
 285         struct commit_list *parents = commit->parents;
 286
 287         while (parents) {
 288                 struct commit *commit = parents->item;
 289                 commit->object.flags |= UNINTERESTING;
 290
 291                 /*
 292                  * Normally we haven't parsed the parent
 293                  * yet, so we won't have a parent of a parent
 294                  * here. However, it may turn out that we've
 295                  * reached this commit some other way (where it
 296                  * wasn't uninteresting), in which case we need
 297                  * to mark its parents recursively too..
 298                  */
 299                 if (commit->parents)
 300                         mark_parents_uninteresting(commit);
 301
 302                 /*
 303                  * A missing commit is ok iff its parent is marked
 304                  * uninteresting.
 305                  *
 306                  * We just mark such a thing parsed, so that when
 307                  * it is popped next time around, we won't be trying
 308                  * to parse it and get an error.
 309                  */
 310                 if (!has_sha1_file(commit->object.sha1))
 311                         commit->object.parsed = 1;
 312                 parents = parents->next;
 313         }
 314 }
 315
 316 static int everybody_uninteresting(struct commit_list *orig)
 317 {
 318         struct commit_list *list = orig;
 319         while (list) {
 320                 struct commit *commit = list->item;
 321                 list = list->next;
 322                 if (commit->object.flags & UNINTERESTING)
 323                         continue;
 324                 return 0;
 325         }
 326         return 1;
 327 }
 328
 329 /*
 330  * This is a truly stupid algorithm, but it's only
 331  * used for bisection, and we just don't care enough.
 332  *
 333  * We care just barely enough to avoid recursing for
 334  * non-merge entries.
 335  */
 336 static int count_distance(struct commit_list *entry)
 337 {
 338         int nr = 0;
 339
 340         while (entry) {
 341                 struct commit *commit = entry->item;
 342                 struct commit_list *p;
 343
 344                 if (commit->object.flags & (UNINTERESTING | COUNTED))
 345                         break;
 346                 nr++;
 347                 commit->object.flags |= COUNTED;
 348                 p = commit->parents;
 349                 entry = p;
 350                 if (p) {
 351                         p = p->next;
 352                         while (p) {
 353                                 nr += count_distance(p);
 354                                 p = p->next;
 355                         }
 356                 }
 357         }
 358         return nr;
 359 }
 360
 361 static void clear_distance(struct commit_list *list)
 362 {
 363         while (list) {
 364                 struct commit *commit = list->item;
 365                 commit->object.flags &= ~COUNTED;
 366                 list = list->next;
 367         }
 368 }
 369
 370 static struct commit_list *find_bisection(struct commit_list *list)
 371 {
 372         int nr, closest;
 373         struct commit_list *p, *best;
 374
 375         nr = 0;
 376         p = list;
 377         while (p) {
 378                 nr++;
 379                 p = p->next;
 380         }
 381         closest = 0;
 382         best = list;
 383
 384         p = list;
 385         while (p) {
 386                 int distance = count_distance(p);
 387                 clear_distance(list);
 388                 if (nr - distance < distance)
 389                         distance = nr - distance;
 390                 if (distance > closest) {
 391                         best = p;
 392                         closest = distance;
 393                 }
 394                 p = p->next;
 395         }
 396         if (best)
 397                 best->next = NULL;
 398         return best;
 399 }
 400
 401 static void mark_edges_uninteresting(struct commit_list *list)
 402 {
 403         for ( ; list; list = list->next) {
 404                 struct commit_list *parents = list->item->parents;
 405
 406                 for ( ; parents; parents = parents->next) {
 407                         struct commit *commit = parents->item;
 408                         if (commit->object.flags & UNINTERESTING)
 409                                 mark_tree_uninteresting(commit->tree);
 410                 }
 411         }
 412 }
 413
 414 static int is_different = 0;
 415
 416 static void file_add_remove(struct diff_options *options,
 417                     int addremove, unsigned mode,
 418                     const unsigned char *sha1,
 419                     const char *base, const char *path)
 420 {
 421         is_different = 1;
 422 }
 423
 424 static void file_change(struct diff_options *options,
 425                  unsigned old_mode, unsigned new_mode,
 426                  const unsigned char *old_sha1,
 427                  const unsigned char *new_sha1,
 428                  const char *base, const char *path)
 429 {
 430         is_different = 1;
 431 }
 432
 433 static struct diff_options diff_opt = {
 434         .recursive = 1,
 435         .add_remove = file_add_remove,
 436         .change = file_change,
 437 };
 438
 439 static int same_tree(struct tree *t1, struct tree *t2)
 440 {
 441         is_different = 0;
 442         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 443                 return 0;
 444         return !is_different;
 445 }
 446
 447 static int same_tree_as_empty(struct tree *t1)
 448 {
 449         int retval;
 450         void *tree;
 451         struct tree_desc empty, real;
 452
 453         if (!t1)
 454                 return 0;
 455
 456         tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 457         if (!tree)
 458                 return 0;
 459         real.buf = tree;
 460
 461         empty.buf = "";
 462         empty.size = 0;
 463
 464         is_different = 0;
 465         retval = diff_tree(&empty, &real, "", &diff_opt);
 466         free(tree);
 467
 468         return retval >= 0 && !is_different;
 469 }
 470
 471 static struct commit *try_to_simplify_merge(struct commit *commit, struct commit_list *parent)
 472 {
 473         if (!commit->tree)
 474                 return NULL;
 475
 476         while (parent) {
 477                 struct commit *p = parent->item;
 478                 parent = parent->next;
 479                 parse_commit(p);
 480                 if (!p->tree)
 481                         continue;
 482                 if (same_tree(commit->tree, p->tree))
 483                         return p;
 484         }
 485         return NULL;
 486 }
 487
 488 static void add_parents_to_list(struct commit *commit, struct commit_list **list)
 489 {
 490         struct commit_list *parent = commit->parents;
 491
 492         /*
 493          * If the commit is uninteresting, don't try to
 494          * prune parents - we want the maximal uninteresting
 495          * set.
 496          *
 497          * Normally we haven't parsed the parent
 498          * yet, so we won't have a parent of a parent
 499          * here. However, it may turn out that we've
 500          * reached this commit some other way (where it
 501          * wasn't uninteresting), in which case we need
 502          * to mark its parents recursively too..
 503          */
 504         if (commit->object.flags & UNINTERESTING) {
 505                 while (parent) {
 506                         struct commit *p = parent->item;
 507                         parent = parent->next;
 508                         parse_commit(p);
 509                         p->object.flags |= UNINTERESTING;
 510                         if (p->parents)
 511                                 mark_parents_uninteresting(p);
 512                         if (p->object.flags & SEEN)
 513                                 continue;
 514                         p->object.flags |= SEEN;
 515                         insert_by_date(p, list);
 516                 }
 517                 return;
 518         }
 519
 520         /*
 521          * Ok, the commit wasn't uninteresting. If it
 522          * is a merge, try to find the parent that has
 523          * no differences in the path set if one exists.
 524          */
 525         if (paths && parent && parent->next) {
 526                 struct commit *preferred;
 527
 528                 preferred = try_to_simplify_merge(commit, parent);
 529                 if (preferred) {
 530                         parent->item = preferred;
 531                         parent->next = NULL;
 532                 }
 533         }
 534
 535         while (parent) {
 536                 struct commit *p = parent->item;
 537
 538                 parent = parent->next;
 539
 540                 parse_commit(p);
 541                 if (p->object.flags & SEEN)
 542                         continue;
 543                 p->object.flags |= SEEN;
 544                 insert_by_date(p, list);
 545         }
 546 }
 547
 548 static void compress_list(struct commit_list *list)
 549 {
 550         while (list) {
 551                 struct commit *commit = list->item;
 552                 struct commit_list *parent = commit->parents;
 553                 list = list->next;
 554
 555                 if (!parent) {
 556                         if (!same_tree_as_empty(commit->tree))
 557                                 commit->object.flags |= TREECHANGE;
 558                         continue;
 559                 }
 560
 561                 /*
 562                  * Exactly one parent? Check if it leaves the tree
 563                  * unchanged
 564                  */
 565                 if (!parent->next) {
 566                         struct tree *t1 = commit->tree;
 567                         struct tree *t2 = parent->item->tree;
 568                         if (!t1 || !t2 || same_tree(t1, t2))
 569                                 continue;
 570                 }
 571                 commit->object.flags |= TREECHANGE;
 572         }
 573 }
 574
 575 static struct commit_list *limit_list(struct commit_list *list)
 576 {
 577         struct commit_list *newlist = NULL;
 578         struct commit_list **p = &newlist;
 579         while (list) {
 580                 struct commit_list *entry = list;
 581                 struct commit *commit = list->item;
 582                 struct object *obj = &commit->object;
 583
 584                 list = list->next;
 585                 free(entry);
 586
 587                 if (max_age != -1 && (commit->date < max_age))
 588                         obj->flags |= UNINTERESTING;
 589                 if (unpacked && has_sha1_pack(obj->sha1))
 590                         obj->flags |= UNINTERESTING;
 591                 add_parents_to_list(commit, &list);
 592                 if (obj->flags & UNINTERESTING) {
 593                         mark_parents_uninteresting(commit);
 594                         if (everybody_uninteresting(list))
 595                                 break;
 596                         continue;
 597                 }
 598                 if (min_age != -1 && (commit->date > min_age))
 599                         continue;
 600                 p = &commit_list_insert(commit, p)->next;
 601         }
 602         if (tree_objects)
 603                 mark_edges_uninteresting(newlist);
 604         if (paths && dense)
 605                 compress_list(newlist);
 606         if (bisect_list)
 607                 newlist = find_bisection(newlist);
 608         return newlist;
 609 }
 610
 611 static void add_pending_object(struct object *obj, const char *name)
 612 {
 613         add_object(obj, &pending_objects, name);
 614 }
 615
 616 static struct commit *get_commit_reference(const char *name, const unsigned char *sha1, unsigned int flags)
 617 {
 618         struct object *object;
 619
 620         object = parse_object(sha1);
 621         if (!object)
 622                 die("bad object %s", name);
 623
 624         /*
 625          * Tag object? Look what it points to..
 626          */
 627         while (object->type == tag_type) {
 628                 struct tag *tag = (struct tag *) object;
 629                 object->flags |= flags;
 630                 if (tag_objects && !(object->flags & UNINTERESTING))
 631                         add_pending_object(object, tag->tag);
 632                 object = parse_object(tag->tagged->sha1);
 633                 if (!object)
 634                         die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 635         }
 636
 637         /*
 638          * Commit object? Just return it, we'll do all the complex
 639          * reachability crud.
 640          */
 641         if (object->type == commit_type) {
 642                 struct commit *commit = (struct commit *)object;
 643                 object->flags |= flags;
 644                 if (parse_commit(commit) < 0)
 645                         die("unable to parse commit %s", name);
 646                 if (flags & UNINTERESTING)
 647                         mark_parents_uninteresting(commit);
 648                 return commit;
 649         }
 650
 651         /*
 652          * Tree object? Either mark it uniniteresting, or add it
 653          * to the list of objects to look at later..
 654          */
 655         if (object->type == tree_type) {
 656                 struct tree *tree = (struct tree *)object;
 657                 if (!tree_objects)
 658                         return NULL;
 659                 if (flags & UNINTERESTING) {
 660                         mark_tree_uninteresting(tree);
 661                         return NULL;
 662                 }
 663                 add_pending_object(object, "");
 664                 return NULL;
 665         }
 666
 667         /*
 668          * Blob object? You know the drill by now..
 669          */
 670         if (object->type == blob_type) {
 671                 struct blob *blob = (struct blob *)object;
 672                 if (!blob_objects)
 673                         return NULL;
 674                 if (flags & UNINTERESTING) {
 675                         mark_blob_uninteresting(blob);
 676                         return NULL;
 677                 }
 678                 add_pending_object(object, "");
 679                 return NULL;
 680         }
 681         die("%s is unknown object", name);
 682 }
 683
 684 static void handle_one_commit(struct commit *com, struct commit_list **lst)
 685 {
 686         if (!com || com->object.flags & SEEN)
 687                 return;
 688         com->object.flags |= SEEN;
 689         commit_list_insert(com, lst);
 690 }
 691
 692 /* for_each_ref() callback does not allow user data -- Yuck. */
 693 static struct commit_list **global_lst;
 694
 695 static int include_one_commit(const char *path, const unsigned char *sha1)
 696 {
 697         struct commit *com = get_commit_reference(path, sha1, 0);
 698         handle_one_commit(com, global_lst);
 699         return 0;
 700 }
 701
 702 static void handle_all(struct commit_list **lst)
 703 {
 704         global_lst = lst;
 705         for_each_ref(include_one_commit);
 706         global_lst = NULL;
 707 }
 708
 709 int main(int argc, const char **argv)
 710 {
 711         const char *prefix = setup_git_directory();
 712         struct commit_list *list = NULL;
 713         int i, limited = 0;
 714
 715         for (i = 1 ; i < argc; i++) {
 716                 int flags;
 717                 const char *arg = argv[i];
 718                 char *dotdot;
 719                 struct commit *commit;
 720                 unsigned char sha1[20];
 721
 722                 if (!strncmp(arg, "--max-count=", 12)) {
 723                         max_count = atoi(arg + 12);
 724                         continue;
 725                 }
 726                 if (!strncmp(arg, "--max-age=", 10)) {
 727                         max_age = atoi(arg + 10);
 728                         limited = 1;
 729                         continue;
 730                 }
 731                 if (!strncmp(arg, "--min-age=", 10)) {
 732                         min_age = atoi(arg + 10);
 733                         limited = 1;
 734                         continue;
 735                 }
 736                 if (!strcmp(arg, "--header")) {
 737                         verbose_header = 1;
 738                         continue;
 739                 }
 740                 if (!strncmp(arg, "--pretty", 8)) {
 741                         commit_format = get_commit_format(arg+8);
 742                         verbose_header = 1;
 743                         hdr_termination = '\n';
 744                         if (commit_format == CMIT_FMT_ONELINE)
 745                                 commit_prefix = "";
 746                         else
 747                                 commit_prefix = "commit ";
 748                         continue;
 749                 }
 750                 if (!strncmp(arg, "--no-merges", 11)) {
 751                         no_merges = 1;
 752                         continue;
 753                 }
 754                 if (!strcmp(arg, "--parents")) {
 755                         show_parents = 1;
 756                         continue;
 757                 }
 758                 if (!strcmp(arg, "--bisect")) {
 759                         bisect_list = 1;
 760                         continue;
 761                 }
 762                 if (!strcmp(arg, "--all")) {
 763                         handle_all(&list);
 764                         continue;
 765                 }
 766                 if (!strcmp(arg, "--objects")) {
 767                         tag_objects = 1;
 768                         tree_objects = 1;
 769                         blob_objects = 1;
 770                         continue;
 771                 }
 772                 if (!strcmp(arg, "--unpacked")) {
 773                         unpacked = 1;
 774                         limited = 1;
 775                         continue;
 776                 }
 777                 if (!strcmp(arg, "--merge-order")) {
 778                         merge_order = 1;
 779                         continue;
 780                 }
 781                 if (!strcmp(arg, "--show-breaks")) {
 782                         show_breaks = 1;
 783                         continue;
 784                 }
 785                 if (!strcmp(arg, "--topo-order")) {
 786                         topo_order = 1;
 787                         limited = 1;
 788                         continue;
 789                 }
 790                 if (!strcmp(arg, "--dense")) {
 791                         dense = 1;
 792                         continue;
 793                 }
 794                 if (!strcmp(arg, "--sparse")) {
 795                         dense = 0;
 796                         continue;
 797                 }
 798                 if (!strcmp(arg, "--")) {
 799                         i++;
 800                         break;
 801                 }
 802
 803                 if (show_breaks && !merge_order)
 804                         usage(rev_list_usage);
 805
 806                 flags = 0;
 807                 dotdot = strstr(arg, "..");
 808                 if (dotdot) {
 809                         unsigned char from_sha1[20];
 810                         char *next = dotdot + 2;
 811                         *dotdot = 0;
 812                         if (!*next)
 813                                 next = "HEAD";
 814                         if (!get_sha1(arg, from_sha1) && !get_sha1(next, sha1)) {
 815                                 struct commit *exclude;
 816                                 struct commit *include;
 817
 818                                 exclude = get_commit_reference(arg, from_sha1, UNINTERESTING);
 819                                 include = get_commit_reference(next, sha1, 0);
 820                                 if (!exclude || !include)
 821                                         die("Invalid revision range %s..%s", arg, next);
 822                                 limited = 1;
 823                                 handle_one_commit(exclude, &list);
 824                                 handle_one_commit(include, &list);
 825                                 continue;
 826                         }
 827                         *dotdot = '.';
 828                 }
 829                 if (*arg == '^') {
 830                         flags = UNINTERESTING;
 831                         arg++;
 832                         limited = 1;
 833                 }
 834                 if (get_sha1(arg, sha1) < 0)
 835                         break;
 836                 commit = get_commit_reference(arg, sha1, flags);
 837                 handle_one_commit(commit, &list);
 838         }
 839
 840         if (!list)
 841                 usage(rev_list_usage);
 842
 843         paths = get_pathspec(prefix, argv + i);
 844         if (paths) {
 845                 limited = 1;
 846                 diff_tree_setup_paths(paths);
 847         }
 848
 849         save_commit_buffer = verbose_header;
 850         track_object_refs = 0;
 851
 852         if (!merge_order) {
 853                 sort_by_date(&list);
 854                 if (list && !limited && max_count == 1 &&
 855                     !tag_objects && !tree_objects && !blob_objects) {
 856                         show_commit(list->item);
 857                         return 0;
 858                 }
 859                 if (limited)
 860                         list = limit_list(list);
 861                 if (topo_order)
 862                         sort_in_topological_order(&list);
 863                 show_commit_list(list);
 864         } else {
 865 #ifndef NO_OPENSSL
 866                 if (sort_list_in_merge_order(list, &process_commit)) {
 867                         die("merge order sort failed\n");
 868                 }
 869 #else
 870                 die("merge order sort unsupported, OpenSSL not linked");
 871 #endif
 872         }
 873
 874         return 0;
 875 }