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 #define TMP_MARK        (1u << 5) /* for isolated cases; clean after use */
  16
  17 static const char rev_list_usage[] =
  18 "git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
  19 "  limiting output:\n"
  20 "    --max-count=nr\n"
  21 "    --max-age=epoch\n"
  22 "    --min-age=epoch\n"
  23 "    --sparse\n"
  24 "    --no-merges\n"
  25 "    --remove-empty\n"
  26 "    --all\n"
  27 "  ordering output:\n"
  28 "    --merge-order [ --show-breaks ]\n"
  29 "    --topo-order\n"
  30 "    --date-order\n"
  31 "  formatting output:\n"
  32 "    --parents\n"
  33 "    --objects\n"
  34 "    --unpacked\n"
  35 "    --header | --pretty\n"
  36 "    --abbrev=nr | --no-abbrev\n"
  37 "  special purpose:\n"
  38 "    --bisect"
  39 ;
  40
  41 static int dense = 1;
  42 static int unpacked = 0;
  43 static int bisect_list = 0;
  44 static int tag_objects = 0;
  45 static int tree_objects = 0;
  46 static int blob_objects = 0;
  47 static int verbose_header = 0;
  48 static int abbrev = DEFAULT_ABBREV;
  49 static int show_parents = 0;
  50 static int hdr_termination = 0;
  51 static const char *commit_prefix = "";
  52 static unsigned long max_age = -1;
  53 static unsigned long min_age = -1;
  54 static int max_count = -1;
  55 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  56 static int merge_order = 0;
  57 static int show_breaks = 0;
  58 static int stop_traversal = 0;
  59 static int topo_order = 0;
  60 static int lifo = 1;
  61 static int no_merges = 0;
  62 static const char **paths = NULL;
  63 static int remove_empty_trees = 0;
  64
  65 static void show_commit(struct commit *commit)
  66 {
  67         commit->object.flags |= SHOWN;
  68         if (show_breaks) {
  69                 commit_prefix = "| ";
  70                 if (commit->object.flags & DISCONTINUITY) {
  71                         commit_prefix = "^ ";
  72                 } else if (commit->object.flags & BOUNDARY) {
  73                         commit_prefix = "= ";
  74                 }
  75         }
  76         printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
  77         if (show_parents) {
  78                 struct commit_list *parents = commit->parents;
  79                 while (parents) {
  80                         struct object *o = &(parents->item->object);
  81                         parents = parents->next;
  82                         if (o->flags & TMP_MARK)
  83                                 continue;
  84                         printf(" %s", sha1_to_hex(o->sha1));
  85                         o->flags |= TMP_MARK;
  86                 }
  87                 /* TMP_MARK is a general purpose flag that can
  88                  * be used locally, but the user should clean
  89                  * things up after it is done with them.
  90                  */
  91                 for (parents = commit->parents;
  92                      parents;
  93                      parents = parents->next)
  94                         parents->item->object.flags &= ~TMP_MARK;
  95         }
  96         if (commit_format == CMIT_FMT_ONELINE)
  97                 putchar(' ');
  98         else
  99                 putchar('\n');
 100
 101         if (verbose_header) {
 102                 static char pretty_header[16384];
 103                 pretty_print_commit(commit_format, commit, ~0, pretty_header, sizeof(pretty_header), abbrev);
 104                 printf("%s%c", pretty_header, hdr_termination);
 105         }
 106         fflush(stdout);
 107 }
 108
 109 static int rewrite_one(struct commit **pp)
 110 {
 111         for (;;) {
 112                 struct commit *p = *pp;
 113                 if (p->object.flags & (TREECHANGE | UNINTERESTING))
 114                         return 0;
 115                 if (!p->parents)
 116                         return -1;
 117                 *pp = p->parents->item;
 118         }
 119 }
 120
 121 static void rewrite_parents(struct commit *commit)
 122 {
 123         struct commit_list **pp = &commit->parents;
 124         while (*pp) {
 125                 struct commit_list *parent = *pp;
 126                 if (rewrite_one(&parent->item) < 0) {
 127                         *pp = parent->next;
 128                         continue;
 129                 }
 130                 pp = &parent->next;
 131         }
 132 }
 133
 134 static int filter_commit(struct commit * commit)
 135 {
 136         if (stop_traversal && (commit->object.flags & BOUNDARY))
 137                 return STOP;
 138         if (commit->object.flags & (UNINTERESTING|SHOWN))
 139                 return CONTINUE;
 140         if (min_age != -1 && (commit->date > min_age))
 141                 return CONTINUE;
 142         if (max_age != -1 && (commit->date < max_age)) {
 143                 stop_traversal=1;
 144                 return CONTINUE;
 145         }
 146         if (no_merges && (commit->parents && commit->parents->next))
 147                 return CONTINUE;
 148         if (paths && dense) {
 149                 if (!(commit->object.flags & TREECHANGE))
 150                         return CONTINUE;
 151                 rewrite_parents(commit);
 152         }
 153         return DO;
 154 }
 155
 156 static int process_commit(struct commit * commit)
 157 {
 158         int action=filter_commit(commit);
 159
 160         if (action == STOP) {
 161                 return STOP;
 162         }
 163
 164         if (action == CONTINUE) {
 165                 return CONTINUE;
 166         }
 167
 168         if (max_count != -1 && !max_count--)
 169                 return STOP;
 170
 171         show_commit(commit);
 172
 173         return CONTINUE;
 174 }
 175
 176 static struct object_list **add_object(struct object *obj, struct object_list **p, const char *name)
 177 {
 178         struct object_list *entry = xmalloc(sizeof(*entry));
 179         entry->item = obj;
 180         entry->next = *p;
 181         entry->name = name;
 182         *p = entry;
 183         return &entry->next;
 184 }
 185
 186 static struct object_list **process_blob(struct blob *blob, struct object_list **p, const char *name)
 187 {
 188         struct object *obj = &blob->object;
 189
 190         if (!blob_objects)
 191                 return p;
 192         if (obj->flags & (UNINTERESTING | SEEN))
 193                 return p;
 194         obj->flags |= SEEN;
 195         return add_object(obj, p, name);
 196 }
 197
 198 static struct object_list **process_tree(struct tree *tree, struct object_list **p, const char *name)
 199 {
 200         struct object *obj = &tree->object;
 201         struct tree_entry_list *entry;
 202
 203         if (!tree_objects)
 204                 return p;
 205         if (obj->flags & (UNINTERESTING | SEEN))
 206                 return p;
 207         if (parse_tree(tree) < 0)
 208                 die("bad tree object %s", sha1_to_hex(obj->sha1));
 209         obj->flags |= SEEN;
 210         p = add_object(obj, p, name);
 211         entry = tree->entries;
 212         tree->entries = NULL;
 213         while (entry) {
 214                 struct tree_entry_list *next = entry->next;
 215                 if (entry->directory)
 216                         p = process_tree(entry->item.tree, p, entry->name);
 217                 else
 218                         p = process_blob(entry->item.blob, p, entry->name);
 219                 free(entry);
 220                 entry = next;
 221         }
 222         return p;
 223 }
 224
 225 static struct object_list *pending_objects = NULL;
 226
 227 static void show_commit_list(struct commit_list *list)
 228 {
 229         struct object_list *objects = NULL, **p = &objects, *pending;
 230         while (list) {
 231                 struct commit *commit = pop_most_recent_commit(&list, SEEN);
 232
 233                 p = process_tree(commit->tree, p, "");
 234                 if (process_commit(commit) == STOP)
 235                         break;
 236         }
 237         for (pending = pending_objects; pending; pending = pending->next) {
 238                 struct object *obj = pending->item;
 239                 const char *name = pending->name;
 240                 if (obj->flags & (UNINTERESTING | SEEN))
 241                         continue;
 242                 if (obj->type == tag_type) {
 243                         obj->flags |= SEEN;
 244                         p = add_object(obj, p, name);
 245                         continue;
 246                 }
 247                 if (obj->type == tree_type) {
 248                         p = process_tree((struct tree *)obj, p, name);
 249                         continue;
 250                 }
 251                 if (obj->type == blob_type) {
 252                         p = process_blob((struct blob *)obj, p, name);
 253                         continue;
 254                 }
 255                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 256         }
 257         while (objects) {
 258                 /* An object with name "foo\n0000000..." can be used to
 259                  * confuse downstream git-pack-objects very badly.
 260                  */
 261                 const char *ep = strchr(objects->name, '\n');
 262                 if (ep) {
 263                         printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 264                                (int) (ep - objects->name),
 265                                objects->name);
 266                 }
 267                 else
 268                         printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 269                 objects = objects->next;
 270         }
 271 }
 272
 273 static void mark_blob_uninteresting(struct blob *blob)
 274 {
 275         if (!blob_objects)
 276                 return;
 277         if (blob->object.flags & UNINTERESTING)
 278                 return;
 279         blob->object.flags |= UNINTERESTING;
 280 }
 281
 282 static void mark_tree_uninteresting(struct tree *tree)
 283 {
 284         struct object *obj = &tree->object;
 285         struct tree_entry_list *entry;
 286
 287         if (!tree_objects)
 288                 return;
 289         if (obj->flags & UNINTERESTING)
 290                 return;
 291         obj->flags |= UNINTERESTING;
 292         if (!has_sha1_file(obj->sha1))
 293                 return;
 294         if (parse_tree(tree) < 0)
 295                 die("bad tree %s", sha1_to_hex(obj->sha1));
 296         entry = tree->entries;
 297         tree->entries = NULL;
 298         while (entry) {
 299                 struct tree_entry_list *next = entry->next;
 300                 if (entry->directory)
 301                         mark_tree_uninteresting(entry->item.tree);
 302                 else
 303                         mark_blob_uninteresting(entry->item.blob);
 304                 free(entry);
 305                 entry = next;
 306         }
 307 }
 308
 309 static void mark_parents_uninteresting(struct commit *commit)
 310 {
 311         struct commit_list *parents = commit->parents;
 312
 313         while (parents) {
 314                 struct commit *commit = parents->item;
 315                 commit->object.flags |= UNINTERESTING;
 316
 317                 /*
 318                  * Normally we haven't parsed the parent
 319                  * yet, so we won't have a parent of a parent
 320                  * here. However, it may turn out that we've
 321                  * reached this commit some other way (where it
 322                  * wasn't uninteresting), in which case we need
 323                  * to mark its parents recursively too..
 324                  */
 325                 if (commit->parents)
 326                         mark_parents_uninteresting(commit);
 327
 328                 /*
 329                  * A missing commit is ok iff its parent is marked
 330                  * uninteresting.
 331                  *
 332                  * We just mark such a thing parsed, so that when
 333                  * it is popped next time around, we won't be trying
 334                  * to parse it and get an error.
 335                  */
 336                 if (!has_sha1_file(commit->object.sha1))
 337                         commit->object.parsed = 1;
 338                 parents = parents->next;
 339         }
 340 }
 341
 342 static int everybody_uninteresting(struct commit_list *orig)
 343 {
 344         struct commit_list *list = orig;
 345         while (list) {
 346                 struct commit *commit = list->item;
 347                 list = list->next;
 348                 if (commit->object.flags & UNINTERESTING)
 349                         continue;
 350                 return 0;
 351         }
 352         return 1;
 353 }
 354
 355 /*
 356  * This is a truly stupid algorithm, but it's only
 357  * used for bisection, and we just don't care enough.
 358  *
 359  * We care just barely enough to avoid recursing for
 360  * non-merge entries.
 361  */
 362 static int count_distance(struct commit_list *entry)
 363 {
 364         int nr = 0;
 365
 366         while (entry) {
 367                 struct commit *commit = entry->item;
 368                 struct commit_list *p;
 369
 370                 if (commit->object.flags & (UNINTERESTING | COUNTED))
 371                         break;
 372                 if (!paths || (commit->object.flags & TREECHANGE))
 373                         nr++;
 374                 commit->object.flags |= COUNTED;
 375                 p = commit->parents;
 376                 entry = p;
 377                 if (p) {
 378                         p = p->next;
 379                         while (p) {
 380                                 nr += count_distance(p);
 381                                 p = p->next;
 382                         }
 383                 }
 384         }
 385
 386         return nr;
 387 }
 388
 389 static void clear_distance(struct commit_list *list)
 390 {
 391         while (list) {
 392                 struct commit *commit = list->item;
 393                 commit->object.flags &= ~COUNTED;
 394                 list = list->next;
 395         }
 396 }
 397
 398 static struct commit_list *find_bisection(struct commit_list *list)
 399 {
 400         int nr, closest;
 401         struct commit_list *p, *best;
 402
 403         nr = 0;
 404         p = list;
 405         while (p) {
 406                 if (!paths || (p->item->object.flags & TREECHANGE))
 407                         nr++;
 408                 p = p->next;
 409         }
 410         closest = 0;
 411         best = list;
 412
 413         for (p = list; p; p = p->next) {
 414                 int distance;
 415
 416                 if (paths && !(p->item->object.flags & TREECHANGE))
 417                         continue;
 418
 419                 distance = count_distance(p);
 420                 clear_distance(list);
 421                 if (nr - distance < distance)
 422                         distance = nr - distance;
 423                 if (distance > closest) {
 424                         best = p;
 425                         closest = distance;
 426                 }
 427         }
 428         if (best)
 429                 best->next = NULL;
 430         return best;
 431 }
 432
 433 static void mark_edges_uninteresting(struct commit_list *list)
 434 {
 435         for ( ; list; list = list->next) {
 436                 struct commit_list *parents = list->item->parents;
 437
 438                 for ( ; parents; parents = parents->next) {
 439                         struct commit *commit = parents->item;
 440                         if (commit->object.flags & UNINTERESTING)
 441                                 mark_tree_uninteresting(commit->tree);
 442                 }
 443         }
 444 }
 445
 446 #define TREE_SAME       0
 447 #define TREE_NEW        1
 448 #define TREE_DIFFERENT  2
 449 static int tree_difference = TREE_SAME;
 450
 451 static void file_add_remove(struct diff_options *options,
 452                     int addremove, unsigned mode,
 453                     const unsigned char *sha1,
 454                     const char *base, const char *path)
 455 {
 456         int diff = TREE_DIFFERENT;
 457
 458         /*
 459          * Is it an add of a new file? It means that
 460          * the old tree didn't have it at all, so we
 461          * will turn "TREE_SAME" -> "TREE_NEW", but
 462          * leave any "TREE_DIFFERENT" alone (and if
 463          * it already was "TREE_NEW", we'll keep it
 464          * "TREE_NEW" of course).
 465          */
 466         if (addremove == '+') {
 467                 diff = tree_difference;
 468                 if (diff != TREE_SAME)
 469                         return;
 470                 diff = TREE_NEW;
 471         }
 472         tree_difference = diff;
 473 }
 474
 475 static void file_change(struct diff_options *options,
 476                  unsigned old_mode, unsigned new_mode,
 477                  const unsigned char *old_sha1,
 478                  const unsigned char *new_sha1,
 479                  const char *base, const char *path)
 480 {
 481         tree_difference = TREE_DIFFERENT;
 482 }
 483
 484 static struct diff_options diff_opt = {
 485         .recursive = 1,
 486         .add_remove = file_add_remove,
 487         .change = file_change,
 488 };
 489
 490 static int compare_tree(struct tree *t1, struct tree *t2)
 491 {
 492         if (!t1)
 493                 return TREE_NEW;
 494         if (!t2)
 495                 return TREE_DIFFERENT;
 496         tree_difference = TREE_SAME;
 497         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 498                 return TREE_DIFFERENT;
 499         return tree_difference;
 500 }
 501
 502 static int same_tree_as_empty(struct tree *t1)
 503 {
 504         int retval;
 505         void *tree;
 506         struct tree_desc empty, real;
 507
 508         if (!t1)
 509                 return 0;
 510
 511         tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 512         if (!tree)
 513                 return 0;
 514         real.buf = tree;
 515
 516         empty.buf = "";
 517         empty.size = 0;
 518
 519         tree_difference = 0;
 520         retval = diff_tree(&empty, &real, "", &diff_opt);
 521         free(tree);
 522
 523         return retval >= 0 && !tree_difference;
 524 }
 525
 526 static void try_to_simplify_commit(struct commit *commit)
 527 {
 528         struct commit_list **pp, *parent;
 529
 530         if (!commit->tree)
 531                 return;
 532
 533         if (!commit->parents) {
 534                 if (!same_tree_as_empty(commit->tree))
 535                         commit->object.flags |= TREECHANGE;
 536                 return;
 537         }
 538
 539         pp = &commit->parents;
 540         while ((parent = *pp) != NULL) {
 541                 struct commit *p = parent->item;
 542
 543                 if (p->object.flags & UNINTERESTING) {
 544                         pp = &parent->next;
 545                         continue;
 546                 }
 547
 548                 parse_commit(p);
 549                 switch (compare_tree(p->tree, commit->tree)) {
 550                 case TREE_SAME:
 551                         parent->next = NULL;
 552                         commit->parents = parent;
 553                         return;
 554
 555                 case TREE_NEW:
 556                         if (remove_empty_trees && same_tree_as_empty(p->tree)) {
 557                                 *pp = parent->next;
 558                                 continue;
 559                         }
 560                 /* fallthrough */
 561                 case TREE_DIFFERENT:
 562                         pp = &parent->next;
 563                         continue;
 564                 }
 565                 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 566         }
 567         commit->object.flags |= TREECHANGE;
 568 }
 569
 570 static void add_parents_to_list(struct commit *commit, struct commit_list **list)
 571 {
 572         struct commit_list *parent = commit->parents;
 573
 574         /*
 575          * If the commit is uninteresting, don't try to
 576          * prune parents - we want the maximal uninteresting
 577          * set.
 578          *
 579          * Normally we haven't parsed the parent
 580          * yet, so we won't have a parent of a parent
 581          * here. However, it may turn out that we've
 582          * reached this commit some other way (where it
 583          * wasn't uninteresting), in which case we need
 584          * to mark its parents recursively too..
 585          */
 586         if (commit->object.flags & UNINTERESTING) {
 587                 while (parent) {
 588                         struct commit *p = parent->item;
 589                         parent = parent->next;
 590                         parse_commit(p);
 591                         p->object.flags |= UNINTERESTING;
 592                         if (p->parents)
 593                                 mark_parents_uninteresting(p);
 594                         if (p->object.flags & SEEN)
 595                                 continue;
 596                         p->object.flags |= SEEN;
 597                         insert_by_date(p, list);
 598                 }
 599                 return;
 600         }
 601
 602         /*
 603          * Ok, the commit wasn't uninteresting. Try to
 604          * simplify the commit history and find the parent
 605          * that has no differences in the path set if one exists.
 606          */
 607         if (paths)
 608                 try_to_simplify_commit(commit);
 609
 610         parent = commit->parents;
 611         while (parent) {
 612                 struct commit *p = parent->item;
 613
 614                 parent = parent->next;
 615
 616                 parse_commit(p);
 617                 if (p->object.flags & SEEN)
 618                         continue;
 619                 p->object.flags |= SEEN;
 620                 insert_by_date(p, list);
 621         }
 622 }
 623
 624 static struct commit_list *limit_list(struct commit_list *list)
 625 {
 626         struct commit_list *newlist = NULL;
 627         struct commit_list **p = &newlist;
 628         while (list) {
 629                 struct commit_list *entry = list;
 630                 struct commit *commit = list->item;
 631                 struct object *obj = &commit->object;
 632
 633                 list = list->next;
 634                 free(entry);
 635
 636                 if (max_age != -1 && (commit->date < max_age))
 637                         obj->flags |= UNINTERESTING;
 638                 if (unpacked && has_sha1_pack(obj->sha1))
 639                         obj->flags |= UNINTERESTING;
 640                 add_parents_to_list(commit, &list);
 641                 if (obj->flags & UNINTERESTING) {
 642                         mark_parents_uninteresting(commit);
 643                         if (everybody_uninteresting(list))
 644                                 break;
 645                         continue;
 646                 }
 647                 if (min_age != -1 && (commit->date > min_age))
 648                         continue;
 649                 p = &commit_list_insert(commit, p)->next;
 650         }
 651         if (tree_objects)
 652                 mark_edges_uninteresting(newlist);
 653         if (bisect_list)
 654                 newlist = find_bisection(newlist);
 655         return newlist;
 656 }
 657
 658 static void add_pending_object(struct object *obj, const char *name)
 659 {
 660         add_object(obj, &pending_objects, name);
 661 }
 662
 663 static struct commit *get_commit_reference(const char *name, const unsigned char *sha1, unsigned int flags)
 664 {
 665         struct object *object;
 666
 667         object = parse_object(sha1);
 668         if (!object)
 669                 die("bad object %s", name);
 670
 671         /*
 672          * Tag object? Look what it points to..
 673          */
 674         while (object->type == tag_type) {
 675                 struct tag *tag = (struct tag *) object;
 676                 object->flags |= flags;
 677                 if (tag_objects && !(object->flags & UNINTERESTING))
 678                         add_pending_object(object, tag->tag);
 679                 object = parse_object(tag->tagged->sha1);
 680                 if (!object)
 681                         die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 682         }
 683
 684         /*
 685          * Commit object? Just return it, we'll do all the complex
 686          * reachability crud.
 687          */
 688         if (object->type == commit_type) {
 689                 struct commit *commit = (struct commit *)object;
 690                 object->flags |= flags;
 691                 if (parse_commit(commit) < 0)
 692                         die("unable to parse commit %s", name);
 693                 if (flags & UNINTERESTING)
 694                         mark_parents_uninteresting(commit);
 695                 return commit;
 696         }
 697
 698         /*
 699          * Tree object? Either mark it uniniteresting, or add it
 700          * to the list of objects to look at later..
 701          */
 702         if (object->type == tree_type) {
 703                 struct tree *tree = (struct tree *)object;
 704                 if (!tree_objects)
 705                         return NULL;
 706                 if (flags & UNINTERESTING) {
 707                         mark_tree_uninteresting(tree);
 708                         return NULL;
 709                 }
 710                 add_pending_object(object, "");
 711                 return NULL;
 712         }
 713
 714         /*
 715          * Blob object? You know the drill by now..
 716          */
 717         if (object->type == blob_type) {
 718                 struct blob *blob = (struct blob *)object;
 719                 if (!blob_objects)
 720                         return NULL;
 721                 if (flags & UNINTERESTING) {
 722                         mark_blob_uninteresting(blob);
 723                         return NULL;
 724                 }
 725                 add_pending_object(object, "");
 726                 return NULL;
 727         }
 728         die("%s is unknown object", name);
 729 }
 730
 731 static void handle_one_commit(struct commit *com, struct commit_list **lst)
 732 {
 733         if (!com || com->object.flags & SEEN)
 734                 return;
 735         com->object.flags |= SEEN;
 736         commit_list_insert(com, lst);
 737 }
 738
 739 /* for_each_ref() callback does not allow user data -- Yuck. */
 740 static struct commit_list **global_lst;
 741
 742 static int include_one_commit(const char *path, const unsigned char *sha1)
 743 {
 744         struct commit *com = get_commit_reference(path, sha1, 0);
 745         handle_one_commit(com, global_lst);
 746         return 0;
 747 }
 748
 749 static void handle_all(struct commit_list **lst)
 750 {
 751         global_lst = lst;
 752         for_each_ref(include_one_commit);
 753         global_lst = NULL;
 754 }
 755
 756 int main(int argc, const char **argv)
 757 {
 758         const char *prefix = setup_git_directory();
 759         struct commit_list *list = NULL;
 760         int i, limited = 0;
 761
 762         for (i = 1 ; i < argc; i++) {
 763                 int flags;
 764                 const char *arg = argv[i];
 765                 char *dotdot;
 766                 struct commit *commit;
 767                 unsigned char sha1[20];
 768
 769                 /* accept -<digit>, like traditilnal "head" */
 770                 if ((*arg == '-') && isdigit(arg[1])) {
 771                         max_count = atoi(arg + 1);
 772                         continue;
 773                 }
 774                 if (!strcmp(arg, "-n")) {
 775                         if (++i >= argc)
 776                                 die("-n requires an argument");
 777                         max_count = atoi(argv[i]);
 778                         continue;
 779                 }
 780                 if (!strncmp(arg,"-n",2)) {
 781                         max_count = atoi(arg + 2);
 782                         continue;
 783                 }
 784                 if (!strncmp(arg, "--max-count=", 12)) {
 785                         max_count = atoi(arg + 12);
 786                         continue;
 787                 }
 788                 if (!strncmp(arg, "--max-age=", 10)) {
 789                         max_age = atoi(arg + 10);
 790                         limited = 1;
 791                         continue;
 792                 }
 793                 if (!strncmp(arg, "--min-age=", 10)) {
 794                         min_age = atoi(arg + 10);
 795                         limited = 1;
 796                         continue;
 797                 }
 798                 if (!strcmp(arg, "--header")) {
 799                         verbose_header = 1;
 800                         continue;
 801                 }
 802                 if (!strcmp(arg, "--no-abbrev")) {
 803                         abbrev = 0;
 804                         continue;
 805                 }
 806                 if (!strncmp(arg, "--abbrev=", 9)) {
 807                         abbrev = strtoul(arg + 9, NULL, 10);
 808                         if (abbrev && abbrev < MINIMUM_ABBREV)
 809                                 abbrev = MINIMUM_ABBREV;
 810                         else if (40 < abbrev)
 811                                 abbrev = 40;
 812                         continue;
 813                 }
 814                 if (!strncmp(arg, "--pretty", 8)) {
 815                         commit_format = get_commit_format(arg+8);
 816                         verbose_header = 1;
 817                         hdr_termination = '\n';
 818                         if (commit_format == CMIT_FMT_ONELINE)
 819                                 commit_prefix = "";
 820                         else
 821                                 commit_prefix = "commit ";
 822                         continue;
 823                 }
 824                 if (!strncmp(arg, "--no-merges", 11)) {
 825                         no_merges = 1;
 826                         continue;
 827                 }
 828                 if (!strcmp(arg, "--parents")) {
 829                         show_parents = 1;
 830                         continue;
 831                 }
 832                 if (!strcmp(arg, "--bisect")) {
 833                         bisect_list = 1;
 834                         continue;
 835                 }
 836                 if (!strcmp(arg, "--all")) {
 837                         handle_all(&list);
 838                         continue;
 839                 }
 840                 if (!strcmp(arg, "--objects")) {
 841                         tag_objects = 1;
 842                         tree_objects = 1;
 843                         blob_objects = 1;
 844                         continue;
 845                 }
 846                 if (!strcmp(arg, "--unpacked")) {
 847                         unpacked = 1;
 848                         limited = 1;
 849                         continue;
 850                 }
 851                 if (!strcmp(arg, "--merge-order")) {
 852                         merge_order = 1;
 853                         continue;
 854                 }
 855                 if (!strcmp(arg, "--show-breaks")) {
 856                         show_breaks = 1;
 857                         continue;
 858                 }
 859                 if (!strcmp(arg, "--topo-order")) {
 860                         topo_order = 1;
 861                         lifo = 1;
 862                         limited = 1;
 863                         continue;
 864                 }
 865                 if (!strcmp(arg, "--date-order")) {
 866                         topo_order = 1;
 867                         lifo = 0;
 868                         limited = 1;
 869                         continue;
 870                 }
 871                 if (!strcmp(arg, "--dense")) {
 872                         dense = 1;
 873                         continue;
 874                 }
 875                 if (!strcmp(arg, "--sparse")) {
 876                         dense = 0;
 877                         continue;
 878                 }
 879                 if (!strcmp(arg, "--remove-empty")) {
 880                         remove_empty_trees = 1;
 881                         continue;
 882                 }
 883                 if (!strcmp(arg, "--")) {
 884                         i++;
 885                         break;
 886                 }
 887
 888                 if (show_breaks && !merge_order)
 889                         usage(rev_list_usage);
 890
 891                 flags = 0;
 892                 dotdot = strstr(arg, "..");
 893                 if (dotdot) {
 894                         unsigned char from_sha1[20];
 895                         char *next = dotdot + 2;
 896                         *dotdot = 0;
 897                         if (!*next)
 898                                 next = "HEAD";
 899                         if (!get_sha1(arg, from_sha1) && !get_sha1(next, sha1)) {
 900                                 struct commit *exclude;
 901                                 struct commit *include;
 902
 903                                 exclude = get_commit_reference(arg, from_sha1, UNINTERESTING);
 904                                 include = get_commit_reference(next, sha1, 0);
 905                                 if (!exclude || !include)
 906                                         die("Invalid revision range %s..%s", arg, next);
 907                                 limited = 1;
 908                                 handle_one_commit(exclude, &list);
 909                                 handle_one_commit(include, &list);
 910                                 continue;
 911                         }
 912                         *dotdot = '.';
 913                 }
 914                 if (*arg == '^') {
 915                         flags = UNINTERESTING;
 916                         arg++;
 917                         limited = 1;
 918                 }
 919                 if (get_sha1(arg, sha1) < 0) {
 920                         struct stat st;
 921                         if (lstat(arg, &st) < 0)
 922                                 die("'%s': %s", arg, strerror(errno));
 923                         break;
 924                 }
 925                 commit = get_commit_reference(arg, sha1, flags);
 926                 handle_one_commit(commit, &list);
 927         }
 928
 929         if (!list &&
 930             (!(tag_objects||tree_objects||blob_objects) && !pending_objects))
 931                 usage(rev_list_usage);
 932
 933         paths = get_pathspec(prefix, argv + i);
 934         if (paths) {
 935                 limited = 1;
 936                 diff_tree_setup_paths(paths);
 937         }
 938
 939         save_commit_buffer = verbose_header;
 940         track_object_refs = 0;
 941
 942         if (!merge_order) {
 943                 sort_by_date(&list);
 944                 if (list && !limited && max_count == 1 &&
 945                     !tag_objects && !tree_objects && !blob_objects) {
 946                         show_commit(list->item);
 947                         return 0;
 948                 }
 949                 if (limited)
 950                         list = limit_list(list);
 951                 if (topo_order)
 952                         sort_in_topological_order(&list, lifo);
 953                 show_commit_list(list);
 954         } else {
 955 #ifndef NO_OPENSSL
 956                 if (sort_list_in_merge_order(list, &process_commit)) {
 957                         die("merge order sort failed\n");
 958                 }
 959 #else
 960                 die("merge order sort unsupported, OpenSSL not linked");
 961 #endif
 962         }
 963
 964         return 0;
 965 }