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 "  formatting output:\n"
  31 "    --parents\n"
  32 "    --objects\n"
  33 "    --unpacked\n"
  34 "    --header | --pretty\n"
  35 "    --abbrev=nr | --no-abbrev\n"
  36 "  special purpose:\n"
  37 "    --bisect"
  38 ;
  39
  40 static int dense = 1;
  41 static int unpacked = 0;
  42 static int bisect_list = 0;
  43 static int tag_objects = 0;
  44 static int tree_objects = 0;
  45 static int blob_objects = 0;
  46 static int verbose_header = 0;
  47 static int abbrev = DEFAULT_ABBREV;
  48 static int show_parents = 0;
  49 static int hdr_termination = 0;
  50 static const char *commit_prefix = "";
  51 static unsigned long max_age = -1;
  52 static unsigned long min_age = -1;
  53 static int max_count = -1;
  54 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  55 static int merge_order = 0;
  56 static int show_breaks = 0;
  57 static int stop_traversal = 0;
  58 static int topo_order = 0;
  59 static int no_merges = 0;
  60 static const char **paths = NULL;
  61 static int remove_empty_trees = 0;
  62
  63 static void show_commit(struct commit *commit)
  64 {
  65         commit->object.flags |= SHOWN;
  66         if (show_breaks) {
  67                 commit_prefix = "| ";
  68                 if (commit->object.flags & DISCONTINUITY) {
  69                         commit_prefix = "^ ";
  70                 } else if (commit->object.flags & BOUNDARY) {
  71                         commit_prefix = "= ";
  72                 }
  73         }
  74         printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
  75         if (show_parents) {
  76                 struct commit_list *parents = commit->parents;
  77                 while (parents) {
  78                         struct object *o = &(parents->item->object);
  79                         parents = parents->next;
  80                         if (o->flags & TMP_MARK)
  81                                 continue;
  82                         printf(" %s", sha1_to_hex(o->sha1));
  83                         o->flags |= TMP_MARK;
  84                 }
  85                 /* TMP_MARK is a general purpose flag that can
  86                  * be used locally, but the user should clean
  87                  * things up after it is done with them.
  88                  */
  89                 for (parents = commit->parents;
  90                      parents;
  91                      parents = parents->next)
  92                         parents->item->object.flags &= ~TMP_MARK;
  93         }
  94         if (commit_format == CMIT_FMT_ONELINE)
  95                 putchar(' ');
  96         else
  97                 putchar('\n');
  98
  99         if (verbose_header) {
 100                 static char pretty_header[16384];
 101                 pretty_print_commit(commit_format, commit, ~0, pretty_header, sizeof(pretty_header), abbrev);
 102                 printf("%s%c", pretty_header, hdr_termination);
 103         }
 104         fflush(stdout);
 105 }
 106
 107 static int rewrite_one(struct commit **pp)
 108 {
 109         for (;;) {
 110                 struct commit *p = *pp;
 111                 if (p->object.flags & (TREECHANGE | UNINTERESTING))
 112                         return 0;
 113                 if (!p->parents)
 114                         return -1;
 115                 *pp = p->parents->item;
 116         }
 117 }
 118
 119 static void rewrite_parents(struct commit *commit)
 120 {
 121         struct commit_list **pp = &commit->parents;
 122         while (*pp) {
 123                 struct commit_list *parent = *pp;
 124                 if (rewrite_one(&parent->item) < 0) {
 125                         *pp = parent->next;
 126                         continue;
 127                 }
 128                 pp = &parent->next;
 129         }
 130 }
 131
 132 static int filter_commit(struct commit * commit)
 133 {
 134         if (stop_traversal && (commit->object.flags & BOUNDARY))
 135                 return STOP;
 136         if (commit->object.flags & (UNINTERESTING|SHOWN))
 137                 return CONTINUE;
 138         if (min_age != -1 && (commit->date > min_age))
 139                 return CONTINUE;
 140         if (max_age != -1 && (commit->date < max_age)) {
 141                 stop_traversal=1;
 142                 return CONTINUE;
 143         }
 144         if (no_merges && (commit->parents && commit->parents->next))
 145                 return CONTINUE;
 146         if (paths && dense) {
 147                 if (!(commit->object.flags & TREECHANGE))
 148                         return CONTINUE;
 149                 rewrite_parents(commit);
 150         }
 151         return DO;
 152 }
 153
 154 static int process_commit(struct commit * commit)
 155 {
 156         int action=filter_commit(commit);
 157
 158         if (action == STOP) {
 159                 return STOP;
 160         }
 161
 162         if (action == CONTINUE) {
 163                 return CONTINUE;
 164         }
 165
 166         if (max_count != -1 && !max_count--)
 167                 return STOP;
 168
 169         show_commit(commit);
 170
 171         return CONTINUE;
 172 }
 173
 174 static struct object_list **add_object(struct object *obj, struct object_list **p, const char *name)
 175 {
 176         struct object_list *entry = xmalloc(sizeof(*entry));
 177         entry->item = obj;
 178         entry->next = *p;
 179         entry->name = name;
 180         *p = entry;
 181         return &entry->next;
 182 }
 183
 184 static struct object_list **process_blob(struct blob *blob, struct object_list **p, const char *name)
 185 {
 186         struct object *obj = &blob->object;
 187
 188         if (!blob_objects)
 189                 return p;
 190         if (obj->flags & (UNINTERESTING | SEEN))
 191                 return p;
 192         obj->flags |= SEEN;
 193         return add_object(obj, p, name);
 194 }
 195
 196 static struct object_list **process_tree(struct tree *tree, struct object_list **p, const char *name)
 197 {
 198         struct object *obj = &tree->object;
 199         struct tree_entry_list *entry;
 200
 201         if (!tree_objects)
 202                 return p;
 203         if (obj->flags & (UNINTERESTING | SEEN))
 204                 return p;
 205         if (parse_tree(tree) < 0)
 206                 die("bad tree object %s", sha1_to_hex(obj->sha1));
 207         obj->flags |= SEEN;
 208         p = add_object(obj, p, name);
 209         entry = tree->entries;
 210         tree->entries = NULL;
 211         while (entry) {
 212                 struct tree_entry_list *next = entry->next;
 213                 if (entry->directory)
 214                         p = process_tree(entry->item.tree, p, entry->name);
 215                 else
 216                         p = process_blob(entry->item.blob, p, entry->name);
 217                 free(entry);
 218                 entry = next;
 219         }
 220         return p;
 221 }
 222
 223 static struct object_list *pending_objects = NULL;
 224
 225 static void show_commit_list(struct commit_list *list)
 226 {
 227         struct object_list *objects = NULL, **p = &objects, *pending;
 228         while (list) {
 229                 struct commit *commit = pop_most_recent_commit(&list, SEEN);
 230
 231                 p = process_tree(commit->tree, p, "");
 232                 if (process_commit(commit) == STOP)
 233                         break;
 234         }
 235         for (pending = pending_objects; pending; pending = pending->next) {
 236                 struct object *obj = pending->item;
 237                 const char *name = pending->name;
 238                 if (obj->flags & (UNINTERESTING | SEEN))
 239                         continue;
 240                 if (obj->type == tag_type) {
 241                         obj->flags |= SEEN;
 242                         p = add_object(obj, p, name);
 243                         continue;
 244                 }
 245                 if (obj->type == tree_type) {
 246                         p = process_tree((struct tree *)obj, p, name);
 247                         continue;
 248                 }
 249                 if (obj->type == blob_type) {
 250                         p = process_blob((struct blob *)obj, p, name);
 251                         continue;
 252                 }
 253                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 254         }
 255         while (objects) {
 256                 /* An object with name "foo\n0000000000000000000000000000000000000000"
 257                  * can be used confuse downstream git-pack-objects very badly.
 258                  */
 259                 const char *ep = strchr(objects->name, '\n');
 260                 if (ep) {
 261                         printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 262                                (int) (ep - objects->name),
 263                                objects->name);
 264                 }
 265                 else
 266                         printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 267                 objects = objects->next;
 268         }
 269 }
 270
 271 static void mark_blob_uninteresting(struct blob *blob)
 272 {
 273         if (!blob_objects)
 274                 return;
 275         if (blob->object.flags & UNINTERESTING)
 276                 return;
 277         blob->object.flags |= UNINTERESTING;
 278 }
 279
 280 static void mark_tree_uninteresting(struct tree *tree)
 281 {
 282         struct object *obj = &tree->object;
 283         struct tree_entry_list *entry;
 284
 285         if (!tree_objects)
 286                 return;
 287         if (obj->flags & UNINTERESTING)
 288                 return;
 289         obj->flags |= UNINTERESTING;
 290         if (!has_sha1_file(obj->sha1))
 291                 return;
 292         if (parse_tree(tree) < 0)
 293                 die("bad tree %s", sha1_to_hex(obj->sha1));
 294         entry = tree->entries;
 295         tree->entries = NULL;
 296         while (entry) {
 297                 struct tree_entry_list *next = entry->next;
 298                 if (entry->directory)
 299                         mark_tree_uninteresting(entry->item.tree);
 300                 else
 301                         mark_blob_uninteresting(entry->item.blob);
 302                 free(entry);
 303                 entry = next;
 304         }
 305 }
 306
 307 static void mark_parents_uninteresting(struct commit *commit)
 308 {
 309         struct commit_list *parents = commit->parents;
 310
 311         while (parents) {
 312                 struct commit *commit = parents->item;
 313                 commit->object.flags |= UNINTERESTING;
 314
 315                 /*
 316                  * Normally we haven't parsed the parent
 317                  * yet, so we won't have a parent of a parent
 318                  * here. However, it may turn out that we've
 319                  * reached this commit some other way (where it
 320                  * wasn't uninteresting), in which case we need
 321                  * to mark its parents recursively too..
 322                  */
 323                 if (commit->parents)
 324                         mark_parents_uninteresting(commit);
 325
 326                 /*
 327                  * A missing commit is ok iff its parent is marked
 328                  * uninteresting.
 329                  *
 330                  * We just mark such a thing parsed, so that when
 331                  * it is popped next time around, we won't be trying
 332                  * to parse it and get an error.
 333                  */
 334                 if (!has_sha1_file(commit->object.sha1))
 335                         commit->object.parsed = 1;
 336                 parents = parents->next;
 337         }
 338 }
 339
 340 static int everybody_uninteresting(struct commit_list *orig)
 341 {
 342         struct commit_list *list = orig;
 343         while (list) {
 344                 struct commit *commit = list->item;
 345                 list = list->next;
 346                 if (commit->object.flags & UNINTERESTING)
 347                         continue;
 348                 return 0;
 349         }
 350         return 1;
 351 }
 352
 353 /*
 354  * This is a truly stupid algorithm, but it's only
 355  * used for bisection, and we just don't care enough.
 356  *
 357  * We care just barely enough to avoid recursing for
 358  * non-merge entries.
 359  */
 360 static int count_distance(struct commit_list *entry)
 361 {
 362         int nr = 0;
 363
 364         while (entry) {
 365                 struct commit *commit = entry->item;
 366                 struct commit_list *p;
 367
 368                 if (commit->object.flags & (UNINTERESTING | COUNTED))
 369                         break;
 370                 if (!paths || (commit->object.flags & TREECHANGE))
 371                         nr++;
 372                 commit->object.flags |= COUNTED;
 373                 p = commit->parents;
 374                 entry = p;
 375                 if (p) {
 376                         p = p->next;
 377                         while (p) {
 378                                 nr += count_distance(p);
 379                                 p = p->next;
 380                         }
 381                 }
 382         }
 383
 384         return nr;
 385 }
 386
 387 static void clear_distance(struct commit_list *list)
 388 {
 389         while (list) {
 390                 struct commit *commit = list->item;
 391                 commit->object.flags &= ~COUNTED;
 392                 list = list->next;
 393         }
 394 }
 395
 396 static struct commit_list *find_bisection(struct commit_list *list)
 397 {
 398         int nr, closest;
 399         struct commit_list *p, *best;
 400
 401         nr = 0;
 402         p = list;
 403         while (p) {
 404                 if (!paths || (p->item->object.flags & TREECHANGE))
 405                         nr++;
 406                 p = p->next;
 407         }
 408         closest = 0;
 409         best = list;
 410
 411         for (p = list; p; p = p->next) {
 412                 int distance;
 413
 414                 if (paths && !(p->item->object.flags & TREECHANGE))
 415                         continue;
 416
 417                 distance = count_distance(p);
 418                 clear_distance(list);
 419                 if (nr - distance < distance)
 420                         distance = nr - distance;
 421                 if (distance > closest) {
 422                         best = p;
 423                         closest = distance;
 424                 }
 425         }
 426         if (best)
 427                 best->next = NULL;
 428         return best;
 429 }
 430
 431 static void mark_edges_uninteresting(struct commit_list *list)
 432 {
 433         for ( ; list; list = list->next) {
 434                 struct commit_list *parents = list->item->parents;
 435
 436                 for ( ; parents; parents = parents->next) {
 437                         struct commit *commit = parents->item;
 438                         if (commit->object.flags & UNINTERESTING)
 439                                 mark_tree_uninteresting(commit->tree);
 440                 }
 441         }
 442 }
 443
 444 #define TREE_SAME       0
 445 #define TREE_NEW        1
 446 #define TREE_DIFFERENT  2
 447 static int tree_difference = TREE_SAME;
 448
 449 static void file_add_remove(struct diff_options *options,
 450                     int addremove, unsigned mode,
 451                     const unsigned char *sha1,
 452                     const char *base, const char *path)
 453 {
 454         int diff = TREE_DIFFERENT;
 455
 456         /*
 457          * Is it an add of a new file? It means that
 458          * the old tree didn't have it at all, so we
 459          * will turn "TREE_SAME" -> "TREE_NEW", but
 460          * leave any "TREE_DIFFERENT" alone (and if
 461          * it already was "TREE_NEW", we'll keep it
 462          * "TREE_NEW" of course).
 463          */
 464         if (addremove == '+') {
 465                 diff = tree_difference;
 466                 if (diff != TREE_SAME)
 467                         return;
 468                 diff = TREE_NEW;
 469         }
 470         tree_difference = diff;
 471 }
 472
 473 static void file_change(struct diff_options *options,
 474                  unsigned old_mode, unsigned new_mode,
 475                  const unsigned char *old_sha1,
 476                  const unsigned char *new_sha1,
 477                  const char *base, const char *path)
 478 {
 479         tree_difference = TREE_DIFFERENT;
 480 }
 481
 482 static struct diff_options diff_opt = {
 483         .recursive = 1,
 484         .add_remove = file_add_remove,
 485         .change = file_change,
 486 };
 487
 488 static int compare_tree(struct tree *t1, struct tree *t2)
 489 {
 490         if (!t1)
 491                 return TREE_NEW;
 492         if (!t2)
 493                 return TREE_DIFFERENT;
 494         tree_difference = TREE_SAME;
 495         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 496                 return TREE_DIFFERENT;
 497         return tree_difference;
 498 }
 499
 500 static int same_tree_as_empty(struct tree *t1)
 501 {
 502         int retval;
 503         void *tree;
 504         struct tree_desc empty, real;
 505
 506         if (!t1)
 507                 return 0;
 508
 509         tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 510         if (!tree)
 511                 return 0;
 512         real.buf = tree;
 513
 514         empty.buf = "";
 515         empty.size = 0;
 516
 517         tree_difference = 0;
 518         retval = diff_tree(&empty, &real, "", &diff_opt);
 519         free(tree);
 520
 521         return retval >= 0 && !tree_difference;
 522 }
 523
 524 static void try_to_simplify_commit(struct commit *commit)
 525 {
 526         struct commit_list **pp, *parent;
 527
 528         if (!commit->tree)
 529                 return;
 530
 531         if (!commit->parents) {
 532                 if (!same_tree_as_empty(commit->tree))
 533                         commit->object.flags |= TREECHANGE;
 534                 return;
 535         }
 536
 537         pp = &commit->parents;
 538         while ((parent = *pp) != NULL) {
 539                 struct commit *p = parent->item;
 540
 541                 if (p->object.flags & UNINTERESTING) {
 542                         pp = &parent->next;
 543                         continue;
 544                 }
 545
 546                 parse_commit(p);
 547                 switch (compare_tree(p->tree, commit->tree)) {
 548                 case TREE_SAME:
 549                         parent->next = NULL;
 550                         commit->parents = parent;
 551                         return;
 552
 553                 case TREE_NEW:
 554                         if (remove_empty_trees && same_tree_as_empty(p->tree)) {
 555                                 *pp = parent->next;
 556                                 continue;
 557                         }
 558                 /* fallthrough */
 559                 case TREE_DIFFERENT:
 560                         pp = &parent->next;
 561                         continue;
 562                 }
 563                 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 564         }
 565         commit->object.flags |= TREECHANGE;
 566 }
 567
 568 static void add_parents_to_list(struct commit *commit, struct commit_list **list)
 569 {
 570         struct commit_list *parent = commit->parents;
 571
 572         /*
 573          * If the commit is uninteresting, don't try to
 574          * prune parents - we want the maximal uninteresting
 575          * set.
 576          *
 577          * Normally we haven't parsed the parent
 578          * yet, so we won't have a parent of a parent
 579          * here. However, it may turn out that we've
 580          * reached this commit some other way (where it
 581          * wasn't uninteresting), in which case we need
 582          * to mark its parents recursively too..
 583          */
 584         if (commit->object.flags & UNINTERESTING) {
 585                 while (parent) {
 586                         struct commit *p = parent->item;
 587                         parent = parent->next;
 588                         parse_commit(p);
 589                         p->object.flags |= UNINTERESTING;
 590                         if (p->parents)
 591                                 mark_parents_uninteresting(p);
 592                         if (p->object.flags & SEEN)
 593                                 continue;
 594                         p->object.flags |= SEEN;
 595                         insert_by_date(p, list);
 596                 }
 597                 return;
 598         }
 599
 600         /*
 601          * Ok, the commit wasn't uninteresting. Try to
 602          * simplify the commit history and find the parent
 603          * that has no differences in the path set if one exists.
 604          */
 605         if (paths)
 606                 try_to_simplify_commit(commit);
 607
 608         parent = commit->parents;
 609         while (parent) {
 610                 struct commit *p = parent->item;
 611
 612                 parent = parent->next;
 613
 614                 parse_commit(p);
 615                 if (p->object.flags & SEEN)
 616                         continue;
 617                 p->object.flags |= SEEN;
 618                 insert_by_date(p, list);
 619         }
 620 }
 621
 622 static struct commit_list *limit_list(struct commit_list *list)
 623 {
 624         struct commit_list *newlist = NULL;
 625         struct commit_list **p = &newlist;
 626         while (list) {
 627                 struct commit_list *entry = list;
 628                 struct commit *commit = list->item;
 629                 struct object *obj = &commit->object;
 630
 631                 list = list->next;
 632                 free(entry);
 633
 634                 if (max_age != -1 && (commit->date < max_age))
 635                         obj->flags |= UNINTERESTING;
 636                 if (unpacked && has_sha1_pack(obj->sha1))
 637                         obj->flags |= UNINTERESTING;
 638                 add_parents_to_list(commit, &list);
 639                 if (obj->flags & UNINTERESTING) {
 640                         mark_parents_uninteresting(commit);
 641                         if (everybody_uninteresting(list))
 642                                 break;
 643                         continue;
 644                 }
 645                 if (min_age != -1 && (commit->date > min_age))
 646                         continue;
 647                 p = &commit_list_insert(commit, p)->next;
 648         }
 649         if (tree_objects)
 650                 mark_edges_uninteresting(newlist);
 651         if (bisect_list)
 652                 newlist = find_bisection(newlist);
 653         return newlist;
 654 }
 655
 656 static void add_pending_object(struct object *obj, const char *name)
 657 {
 658         add_object(obj, &pending_objects, name);
 659 }
 660
 661 static struct commit *get_commit_reference(const char *name, const unsigned char *sha1, unsigned int flags)
 662 {
 663         struct object *object;
 664
 665         object = parse_object(sha1);
 666         if (!object)
 667                 die("bad object %s", name);
 668
 669         /*
 670          * Tag object? Look what it points to..
 671          */
 672         while (object->type == tag_type) {
 673                 struct tag *tag = (struct tag *) object;
 674                 object->flags |= flags;
 675                 if (tag_objects && !(object->flags & UNINTERESTING))
 676                         add_pending_object(object, tag->tag);
 677                 object = parse_object(tag->tagged->sha1);
 678                 if (!object)
 679                         die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 680         }
 681
 682         /*
 683          * Commit object? Just return it, we'll do all the complex
 684          * reachability crud.
 685          */
 686         if (object->type == commit_type) {
 687                 struct commit *commit = (struct commit *)object;
 688                 object->flags |= flags;
 689                 if (parse_commit(commit) < 0)
 690                         die("unable to parse commit %s", name);
 691                 if (flags & UNINTERESTING)
 692                         mark_parents_uninteresting(commit);
 693                 return commit;
 694         }
 695
 696         /*
 697          * Tree object? Either mark it uniniteresting, or add it
 698          * to the list of objects to look at later..
 699          */
 700         if (object->type == tree_type) {
 701                 struct tree *tree = (struct tree *)object;
 702                 if (!tree_objects)
 703                         return NULL;
 704                 if (flags & UNINTERESTING) {
 705                         mark_tree_uninteresting(tree);
 706                         return NULL;
 707                 }
 708                 add_pending_object(object, "");
 709                 return NULL;
 710         }
 711
 712         /*
 713          * Blob object? You know the drill by now..
 714          */
 715         if (object->type == blob_type) {
 716                 struct blob *blob = (struct blob *)object;
 717                 if (!blob_objects)
 718                         return NULL;
 719                 if (flags & UNINTERESTING) {
 720                         mark_blob_uninteresting(blob);
 721                         return NULL;
 722                 }
 723                 add_pending_object(object, "");
 724                 return NULL;
 725         }
 726         die("%s is unknown object", name);
 727 }
 728
 729 static void handle_one_commit(struct commit *com, struct commit_list **lst)
 730 {
 731         if (!com || com->object.flags & SEEN)
 732                 return;
 733         com->object.flags |= SEEN;
 734         commit_list_insert(com, lst);
 735 }
 736
 737 /* for_each_ref() callback does not allow user data -- Yuck. */
 738 static struct commit_list **global_lst;
 739
 740 static int include_one_commit(const char *path, const unsigned char *sha1)
 741 {
 742         struct commit *com = get_commit_reference(path, sha1, 0);
 743         handle_one_commit(com, global_lst);
 744         return 0;
 745 }
 746
 747 static void handle_all(struct commit_list **lst)
 748 {
 749         global_lst = lst;
 750         for_each_ref(include_one_commit);
 751         global_lst = NULL;
 752 }
 753
 754 int main(int argc, const char **argv)
 755 {
 756         const char *prefix = setup_git_directory();
 757         struct commit_list *list = NULL;
 758         int i, limited = 0;
 759
 760         for (i = 1 ; i < argc; i++) {
 761                 int flags;
 762                 const char *arg = argv[i];
 763                 char *dotdot;
 764                 struct commit *commit;
 765                 unsigned char sha1[20];
 766
 767                 /* accept -<digit>, like traditilnal "head" */
 768                 if ((*arg == '-') && isdigit(arg[1])) {
 769                         max_count = atoi(arg + 1);
 770                         continue;
 771                 }
 772                 if (!strcmp(arg, "-n")) {
 773                         if (++i >= argc)
 774                                 die("-n requires an argument");
 775                         max_count = atoi(argv[i]);
 776                         continue;
 777                 }
 778                 if (!strncmp(arg,"-n",2)) {
 779                         max_count = atoi(arg + 2);
 780                         continue;
 781                 }
 782                 if (!strncmp(arg, "--max-count=", 12)) {
 783                         max_count = atoi(arg + 12);
 784                         continue;
 785                 }
 786                 if (!strncmp(arg, "--max-age=", 10)) {
 787                         max_age = atoi(arg + 10);
 788                         limited = 1;
 789                         continue;
 790                 }
 791                 if (!strncmp(arg, "--min-age=", 10)) {
 792                         min_age = atoi(arg + 10);
 793                         limited = 1;
 794                         continue;
 795                 }
 796                 if (!strcmp(arg, "--header")) {
 797                         verbose_header = 1;
 798                         continue;
 799                 }
 800                 if (!strcmp(arg, "--no-abbrev")) {
 801                         abbrev = 0;
 802                         continue;
 803                 }
 804                 if (!strncmp(arg, "--abbrev=", 9)) {
 805                         abbrev = strtoul(arg + 9, NULL, 10);
 806                         if (abbrev && abbrev < MINIMUM_ABBREV)
 807                                 abbrev = MINIMUM_ABBREV;
 808                         else if (40 < abbrev)
 809                                 abbrev = 40;
 810                         continue;
 811                 }
 812                 if (!strncmp(arg, "--pretty", 8)) {
 813                         commit_format = get_commit_format(arg+8);
 814                         verbose_header = 1;
 815                         hdr_termination = '\n';
 816                         if (commit_format == CMIT_FMT_ONELINE)
 817                                 commit_prefix = "";
 818                         else
 819                                 commit_prefix = "commit ";
 820                         continue;
 821                 }
 822                 if (!strncmp(arg, "--no-merges", 11)) {
 823                         no_merges = 1;
 824                         continue;
 825                 }
 826                 if (!strcmp(arg, "--parents")) {
 827                         show_parents = 1;
 828                         continue;
 829                 }
 830                 if (!strcmp(arg, "--bisect")) {
 831                         bisect_list = 1;
 832                         continue;
 833                 }
 834                 if (!strcmp(arg, "--all")) {
 835                         handle_all(&list);
 836                         continue;
 837                 }
 838                 if (!strcmp(arg, "--objects")) {
 839                         tag_objects = 1;
 840                         tree_objects = 1;
 841                         blob_objects = 1;
 842                         continue;
 843                 }
 844                 if (!strcmp(arg, "--unpacked")) {
 845                         unpacked = 1;
 846                         limited = 1;
 847                         continue;
 848                 }
 849                 if (!strcmp(arg, "--merge-order")) {
 850                         merge_order = 1;
 851                         continue;
 852                 }
 853                 if (!strcmp(arg, "--show-breaks")) {
 854                         show_breaks = 1;
 855                         continue;
 856                 }
 857                 if (!strcmp(arg, "--topo-order")) {
 858                         topo_order = 1;
 859                         limited = 1;
 860                         continue;
 861                 }
 862                 if (!strcmp(arg, "--dense")) {
 863                         dense = 1;
 864                         continue;
 865                 }
 866                 if (!strcmp(arg, "--sparse")) {
 867                         dense = 0;
 868                         continue;
 869                 }
 870                 if (!strcmp(arg, "--remove-empty")) {
 871                         remove_empty_trees = 1;
 872                         continue;
 873                 }
 874                 if (!strcmp(arg, "--")) {
 875                         i++;
 876                         break;
 877                 }
 878
 879                 if (show_breaks && !merge_order)
 880                         usage(rev_list_usage);
 881
 882                 flags = 0;
 883                 dotdot = strstr(arg, "..");
 884                 if (dotdot) {
 885                         unsigned char from_sha1[20];
 886                         char *next = dotdot + 2;
 887                         *dotdot = 0;
 888                         if (!*next)
 889                                 next = "HEAD";
 890                         if (!get_sha1(arg, from_sha1) && !get_sha1(next, sha1)) {
 891                                 struct commit *exclude;
 892                                 struct commit *include;
 893
 894                                 exclude = get_commit_reference(arg, from_sha1, UNINTERESTING);
 895                                 include = get_commit_reference(next, sha1, 0);
 896                                 if (!exclude || !include)
 897                                         die("Invalid revision range %s..%s", arg, next);
 898                                 limited = 1;
 899                                 handle_one_commit(exclude, &list);
 900                                 handle_one_commit(include, &list);
 901                                 continue;
 902                         }
 903                         *dotdot = '.';
 904                 }
 905                 if (*arg == '^') {
 906                         flags = UNINTERESTING;
 907                         arg++;
 908                         limited = 1;
 909                 }
 910                 if (get_sha1(arg, sha1) < 0) {
 911                         struct stat st;
 912                         if (lstat(arg, &st) < 0)
 913                                 die("'%s': %s", arg, strerror(errno));
 914                         break;
 915                 }
 916                 commit = get_commit_reference(arg, sha1, flags);
 917                 handle_one_commit(commit, &list);
 918         }
 919
 920         if (!list &&
 921             (!(tag_objects||tree_objects||blob_objects) && !pending_objects))
 922                 usage(rev_list_usage);
 923
 924         paths = get_pathspec(prefix, argv + i);
 925         if (paths) {
 926                 limited = 1;
 927                 diff_tree_setup_paths(paths);
 928         }
 929
 930         save_commit_buffer = verbose_header;
 931         track_object_refs = 0;
 932
 933         if (!merge_order) {
 934                 sort_by_date(&list);
 935                 if (list && !limited && max_count == 1 &&
 936                     !tag_objects && !tree_objects && !blob_objects) {
 937                         show_commit(list->item);
 938                         return 0;
 939                 }
 940                 if (limited)
 941                         list = limit_list(list);
 942                 if (topo_order)
 943                         sort_in_topological_order(&list);
 944                 show_commit_list(list);
 945         } else {
 946 #ifndef NO_OPENSSL
 947                 if (sort_list_in_merge_order(list, &process_commit)) {
 948                         die("merge order sort failed\n");
 949                 }
 950 #else
 951                 die("merge order sort unsupported, OpenSSL not linked");
 952 #endif
 953         }
 954
 955         return 0;
 956 }