revision.c

   1 #include "cache.h"
   2 #include "tag.h"
   3 #include "blob.h"
   4 #include "tree.h"
   5 #include "commit.h"
   6 #include "diff.h"
   7 #include "refs.h"
   8 #include "revision.h"
   9
  10 static char *path_name(struct name_path *path, const char *name)
  11 {
  12         struct name_path *p;
  13         char *n, *m;
  14         int nlen = strlen(name);
  15         int len = nlen + 1;
  16
  17         for (p = path; p; p = p->up) {
  18                 if (p->elem_len)
  19                         len += p->elem_len + 1;
  20         }
  21         n = xmalloc(len);
  22         m = n + len - (nlen + 1);
  23         strcpy(m, name);
  24         for (p = path; p; p = p->up) {
  25                 if (p->elem_len) {
  26                         m -= p->elem_len + 1;
  27                         memcpy(m, p->elem, p->elem_len);
  28                         m[p->elem_len] = '/';
  29                 }
  30         }
  31         return n;
  32 }
  33
  34 struct object_list **add_object(struct object *obj,
  35                                        struct object_list **p,
  36                                        struct name_path *path,
  37                                        const char *name)
  38 {
  39         struct object_list *entry = xmalloc(sizeof(*entry));
  40         entry->item = obj;
  41         entry->next = *p;
  42         entry->name = path_name(path, name);
  43         *p = entry;
  44         return &entry->next;
  45 }
  46
  47 static void mark_blob_uninteresting(struct blob *blob)
  48 {
  49         if (blob->object.flags & UNINTERESTING)
  50                 return;
  51         blob->object.flags |= UNINTERESTING;
  52 }
  53
  54 void mark_tree_uninteresting(struct tree *tree)
  55 {
  56         struct object *obj = &tree->object;
  57         struct tree_entry_list *entry;
  58
  59         if (obj->flags & UNINTERESTING)
  60                 return;
  61         obj->flags |= UNINTERESTING;
  62         if (!has_sha1_file(obj->sha1))
  63                 return;
  64         if (parse_tree(tree) < 0)
  65                 die("bad tree %s", sha1_to_hex(obj->sha1));
  66         entry = tree->entries;
  67         tree->entries = NULL;
  68         while (entry) {
  69                 struct tree_entry_list *next = entry->next;
  70                 if (entry->directory)
  71                         mark_tree_uninteresting(entry->item.tree);
  72                 else
  73                         mark_blob_uninteresting(entry->item.blob);
  74                 free(entry);
  75                 entry = next;
  76         }
  77 }
  78
  79 void mark_parents_uninteresting(struct commit *commit)
  80 {
  81         struct commit_list *parents = commit->parents;
  82
  83         while (parents) {
  84                 struct commit *commit = parents->item;
  85                 if (!(commit->object.flags & UNINTERESTING)) {
  86                         commit->object.flags |= UNINTERESTING;
  87
  88                         /*
  89                          * Normally we haven't parsed the parent
  90                          * yet, so we won't have a parent of a parent
  91                          * here. However, it may turn out that we've
  92                          * reached this commit some other way (where it
  93                          * wasn't uninteresting), in which case we need
  94                          * to mark its parents recursively too..
  95                          */
  96                         if (commit->parents)
  97                                 mark_parents_uninteresting(commit);
  98                 }
  99
 100                 /*
 101                  * A missing commit is ok iff its parent is marked
 102                  * uninteresting.
 103                  *
 104                  * We just mark such a thing parsed, so that when
 105                  * it is popped next time around, we won't be trying
 106                  * to parse it and get an error.
 107                  */
 108                 if (!has_sha1_file(commit->object.sha1))
 109                         commit->object.parsed = 1;
 110                 parents = parents->next;
 111         }
 112 }
 113
 114 static void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 115 {
 116         add_object(obj, &revs->pending_objects, NULL, name);
 117 }
 118
 119 static struct commit *get_commit_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 120 {
 121         struct object *object;
 122
 123         object = parse_object(sha1);
 124         if (!object)
 125                 die("bad object %s", name);
 126
 127         /*
 128          * Tag object? Look what it points to..
 129          */
 130         while (object->type == tag_type) {
 131                 struct tag *tag = (struct tag *) object;
 132                 object->flags |= flags;
 133                 if (revs->tag_objects && !(object->flags & UNINTERESTING))
 134                         add_pending_object(revs, object, tag->tag);
 135                 object = parse_object(tag->tagged->sha1);
 136                 if (!object)
 137                         die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 138         }
 139
 140         /*
 141          * Commit object? Just return it, we'll do all the complex
 142          * reachability crud.
 143          */
 144         if (object->type == commit_type) {
 145                 struct commit *commit = (struct commit *)object;
 146                 object->flags |= flags;
 147                 if (parse_commit(commit) < 0)
 148                         die("unable to parse commit %s", name);
 149                 if (flags & UNINTERESTING) {
 150                         mark_parents_uninteresting(commit);
 151                         revs->limited = 1;
 152                 }
 153                 return commit;
 154         }
 155
 156         /*
 157          * Tree object? Either mark it uniniteresting, or add it
 158          * to the list of objects to look at later..
 159          */
 160         if (object->type == tree_type) {
 161                 struct tree *tree = (struct tree *)object;
 162                 if (!revs->tree_objects)
 163                         return NULL;
 164                 if (flags & UNINTERESTING) {
 165                         mark_tree_uninteresting(tree);
 166                         return NULL;
 167                 }
 168                 add_pending_object(revs, object, "");
 169                 return NULL;
 170         }
 171
 172         /*
 173          * Blob object? You know the drill by now..
 174          */
 175         if (object->type == blob_type) {
 176                 struct blob *blob = (struct blob *)object;
 177                 if (!revs->blob_objects)
 178                         return NULL;
 179                 if (flags & UNINTERESTING) {
 180                         mark_blob_uninteresting(blob);
 181                         return NULL;
 182                 }
 183                 add_pending_object(revs, object, "");
 184                 return NULL;
 185         }
 186         die("%s is unknown object", name);
 187 }
 188
 189 static int everybody_uninteresting(struct commit_list *orig)
 190 {
 191         struct commit_list *list = orig;
 192         while (list) {
 193                 struct commit *commit = list->item;
 194                 list = list->next;
 195                 if (commit->object.flags & UNINTERESTING)
 196                         continue;
 197                 return 0;
 198         }
 199         return 1;
 200 }
 201
 202 static int tree_difference = REV_TREE_SAME;
 203
 204 static void file_add_remove(struct diff_options *options,
 205                     int addremove, unsigned mode,
 206                     const unsigned char *sha1,
 207                     const char *base, const char *path)
 208 {
 209         int diff = REV_TREE_DIFFERENT;
 210
 211         /*
 212          * Is it an add of a new file? It means that the old tree
 213          * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 214          * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 215          * (and if it already was "REV_TREE_NEW", we'll keep it
 216          * "REV_TREE_NEW" of course).
 217          */
 218         if (addremove == '+') {
 219                 diff = tree_difference;
 220                 if (diff != REV_TREE_SAME)
 221                         return;
 222                 diff = REV_TREE_NEW;
 223         }
 224         tree_difference = diff;
 225 }
 226
 227 static void file_change(struct diff_options *options,
 228                  unsigned old_mode, unsigned new_mode,
 229                  const unsigned char *old_sha1,
 230                  const unsigned char *new_sha1,
 231                  const char *base, const char *path)
 232 {
 233         tree_difference = REV_TREE_DIFFERENT;
 234 }
 235
 236 int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 237 {
 238         if (!t1)
 239                 return REV_TREE_NEW;
 240         if (!t2)
 241                 return REV_TREE_DIFFERENT;
 242         tree_difference = REV_TREE_SAME;
 243         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 244                            &revs->diffopt) < 0)
 245                 return REV_TREE_DIFFERENT;
 246         return tree_difference;
 247 }
 248
 249 int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 250 {
 251         int retval;
 252         void *tree;
 253         struct tree_desc empty, real;
 254
 255         if (!t1)
 256                 return 0;
 257
 258         tree = read_object_with_reference(t1->object.sha1, tree_type, &real.size, NULL);
 259         if (!tree)
 260                 return 0;
 261         real.buf = tree;
 262
 263         empty.buf = "";
 264         empty.size = 0;
 265
 266         tree_difference = 0;
 267         retval = diff_tree(&empty, &real, "", &revs->diffopt);
 268         free(tree);
 269
 270         return retval >= 0 && !tree_difference;
 271 }
 272
 273 static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 274 {
 275         struct commit_list **pp, *parent;
 276         int tree_changed = 0;
 277
 278         if (!commit->tree)
 279                 return;
 280
 281         if (!commit->parents) {
 282                 if (!rev_same_tree_as_empty(revs, commit->tree))
 283                         commit->object.flags |= TREECHANGE;
 284                 return;
 285         }
 286
 287         pp = &commit->parents;
 288         while ((parent = *pp) != NULL) {
 289                 struct commit *p = parent->item;
 290
 291                 parse_commit(p);
 292                 switch (rev_compare_tree(revs, p->tree, commit->tree)) {
 293                 case REV_TREE_SAME:
 294                         if (p->object.flags & UNINTERESTING) {
 295                                 /* Even if a merge with an uninteresting
 296                                  * side branch brought the entire change
 297                                  * we are interested in, we do not want
 298                                  * to lose the other branches of this
 299                                  * merge, so we just keep going.
 300                                  */
 301                                 pp = &parent->next;
 302                                 continue;
 303                         }
 304                         parent->next = NULL;
 305                         commit->parents = parent;
 306                         return;
 307
 308                 case REV_TREE_NEW:
 309                         if (revs->remove_empty_trees &&
 310                             rev_same_tree_as_empty(revs, p->tree)) {
 311                                 /* We are adding all the specified
 312                                  * paths from this parent, so the
 313                                  * history beyond this parent is not
 314                                  * interesting.  Remove its parents
 315                                  * (they are grandparents for us).
 316                                  * IOW, we pretend this parent is a
 317                                  * "root" commit.
 318                                  */
 319                                 parse_commit(p);
 320                                 p->parents = NULL;
 321                         }
 322                 /* fallthrough */
 323                 case REV_TREE_DIFFERENT:
 324                         tree_changed = 1;
 325                         pp = &parent->next;
 326                         continue;
 327                 }
 328                 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 329         }
 330         if (tree_changed)
 331                 commit->object.flags |= TREECHANGE;
 332 }
 333
 334 static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 335 {
 336         struct commit_list *parent = commit->parents;
 337
 338         if (commit->object.flags & ADDED)
 339                 return;
 340         commit->object.flags |= ADDED;
 341
 342         /*
 343          * If the commit is uninteresting, don't try to
 344          * prune parents - we want the maximal uninteresting
 345          * set.
 346          *
 347          * Normally we haven't parsed the parent
 348          * yet, so we won't have a parent of a parent
 349          * here. However, it may turn out that we've
 350          * reached this commit some other way (where it
 351          * wasn't uninteresting), in which case we need
 352          * to mark its parents recursively too..
 353          */
 354         if (commit->object.flags & UNINTERESTING) {
 355                 while (parent) {
 356                         struct commit *p = parent->item;
 357                         parent = parent->next;
 358                         parse_commit(p);
 359                         p->object.flags |= UNINTERESTING;
 360                         if (p->parents)
 361                                 mark_parents_uninteresting(p);
 362                         if (p->object.flags & SEEN)
 363                                 continue;
 364                         p->object.flags |= SEEN;
 365                         insert_by_date(p, list);
 366                 }
 367                 return;
 368         }
 369
 370         /*
 371          * Ok, the commit wasn't uninteresting. Try to
 372          * simplify the commit history and find the parent
 373          * that has no differences in the path set if one exists.
 374          */
 375         if (revs->prune_fn)
 376                 revs->prune_fn(revs, commit);
 377
 378         if (revs->no_walk)
 379                 return;
 380
 381         parent = commit->parents;
 382         while (parent) {
 383                 struct commit *p = parent->item;
 384
 385                 parent = parent->next;
 386
 387                 parse_commit(p);
 388                 if (p->object.flags & SEEN)
 389                         continue;
 390                 p->object.flags |= SEEN;
 391                 insert_by_date(p, list);
 392         }
 393 }
 394
 395 static void limit_list(struct rev_info *revs)
 396 {
 397         struct commit_list *list = revs->commits;
 398         struct commit_list *newlist = NULL;
 399         struct commit_list **p = &newlist;
 400
 401         while (list) {
 402                 struct commit_list *entry = list;
 403                 struct commit *commit = list->item;
 404                 struct object *obj = &commit->object;
 405
 406                 list = list->next;
 407                 free(entry);
 408
 409                 if (revs->max_age != -1 && (commit->date < revs->max_age))
 410                         obj->flags |= UNINTERESTING;
 411                 if (revs->unpacked && has_sha1_pack(obj->sha1))
 412                         obj->flags |= UNINTERESTING;
 413                 add_parents_to_list(revs, commit, &list);
 414                 if (obj->flags & UNINTERESTING) {
 415                         mark_parents_uninteresting(commit);
 416                         if (everybody_uninteresting(list))
 417                                 break;
 418                         continue;
 419                 }
 420                 if (revs->min_age != -1 && (commit->date > revs->min_age))
 421                         continue;
 422                 p = &commit_list_insert(commit, p)->next;
 423         }
 424         if (revs->boundary) {
 425                 /* mark the ones that are on the result list first */
 426                 for (list = newlist; list; list = list->next) {
 427                         struct commit *commit = list->item;
 428                         commit->object.flags |= TMP_MARK;
 429                 }
 430                 for (list = newlist; list; list = list->next) {
 431                         struct commit *commit = list->item;
 432                         struct object *obj = &commit->object;
 433                         struct commit_list *parent;
 434                         if (obj->flags & UNINTERESTING)
 435                                 continue;
 436                         for (parent = commit->parents;
 437                              parent;
 438                              parent = parent->next) {
 439                                 struct commit *pcommit = parent->item;
 440                                 if (!(pcommit->object.flags & UNINTERESTING))
 441                                         continue;
 442                                 pcommit->object.flags |= BOUNDARY;
 443                                 if (pcommit->object.flags & TMP_MARK)
 444                                         continue;
 445                                 pcommit->object.flags |= TMP_MARK;
 446                                 p = &commit_list_insert(pcommit, p)->next;
 447                         }
 448                 }
 449                 for (list = newlist; list; list = list->next) {
 450                         struct commit *commit = list->item;
 451                         commit->object.flags &= ~TMP_MARK;
 452                 }
 453         }
 454         revs->commits = newlist;
 455 }
 456
 457 static void add_one_commit(struct commit *commit, struct rev_info *revs)
 458 {
 459         if (!commit || (commit->object.flags & SEEN))
 460                 return;
 461         commit->object.flags |= SEEN;
 462         commit_list_insert(commit, &revs->commits);
 463 }
 464
 465 static int all_flags;
 466 static struct rev_info *all_revs;
 467
 468 static int handle_one_ref(const char *path, const unsigned char *sha1)
 469 {
 470         struct commit *commit = get_commit_reference(all_revs, path, sha1, all_flags);
 471         add_one_commit(commit, all_revs);
 472         return 0;
 473 }
 474
 475 static void handle_all(struct rev_info *revs, unsigned flags)
 476 {
 477         all_revs = revs;
 478         all_flags = flags;
 479         for_each_ref(handle_one_ref);
 480 }
 481
 482 void init_revisions(struct rev_info *revs)
 483 {
 484         memset(revs, 0, sizeof(*revs));
 485         revs->diffopt.recursive = 1;
 486         revs->diffopt.add_remove = file_add_remove;
 487         revs->diffopt.change = file_change;
 488         revs->lifo = 1;
 489         revs->dense = 1;
 490         revs->prefix = setup_git_directory();
 491         revs->max_age = -1;
 492         revs->min_age = -1;
 493         revs->max_count = -1;
 494
 495         revs->prune_fn = NULL;
 496         revs->prune_data = NULL;
 497
 498         revs->topo_setter = topo_sort_default_setter;
 499         revs->topo_getter = topo_sort_default_getter;
 500 }
 501
 502 /*
 503  * Parse revision information, filling in the "rev_info" structure,
 504  * and removing the used arguments from the argument list.
 505  *
 506  * Returns the number of arguments left that weren't recognized
 507  * (which are also moved to the head of the argument list)
 508  */
 509 int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 510 {
 511         int i, flags, seen_dashdash;
 512         const char **unrecognized = argv + 1;
 513         int left = 1;
 514
 515         init_revisions(revs);
 516
 517         /* First, search for "--" */
 518         seen_dashdash = 0;
 519         for (i = 1; i < argc; i++) {
 520                 const char *arg = argv[i];
 521                 if (strcmp(arg, "--"))
 522                         continue;
 523                 argv[i] = NULL;
 524                 argc = i;
 525                 revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 526                 seen_dashdash = 1;
 527                 break;
 528         }
 529
 530         flags = 0;
 531         for (i = 1; i < argc; i++) {
 532                 struct commit *commit;
 533                 const char *arg = argv[i];
 534                 unsigned char sha1[20];
 535                 char *dotdot;
 536                 int local_flags;
 537
 538                 if (*arg == '-') {
 539                         if (!strncmp(arg, "--max-count=", 12)) {
 540                                 revs->max_count = atoi(arg + 12);
 541                                 continue;
 542                         }
 543                         /* accept -<digit>, like traditilnal "head" */
 544                         if ((*arg == '-') && isdigit(arg[1])) {
 545                                 revs->max_count = atoi(arg + 1);
 546                                 continue;
 547                         }
 548                         if (!strcmp(arg, "-n")) {
 549                                 if (argc <= i + 1)
 550                                         die("-n requires an argument");
 551                                 revs->max_count = atoi(argv[++i]);
 552                                 continue;
 553                         }
 554                         if (!strncmp(arg,"-n",2)) {
 555                                 revs->max_count = atoi(arg + 2);
 556                                 continue;
 557                         }
 558                         if (!strncmp(arg, "--max-age=", 10)) {
 559                                 revs->max_age = atoi(arg + 10);
 560                                 continue;
 561                         }
 562                         if (!strncmp(arg, "--since=", 8)) {
 563                                 revs->max_age = approxidate(arg + 8);
 564                                 continue;
 565                         }
 566                         if (!strncmp(arg, "--after=", 8)) {
 567                                 revs->max_age = approxidate(arg + 8);
 568                                 continue;
 569                         }
 570                         if (!strncmp(arg, "--min-age=", 10)) {
 571                                 revs->min_age = atoi(arg + 10);
 572                                 continue;
 573                         }
 574                         if (!strncmp(arg, "--before=", 9)) {
 575                                 revs->min_age = approxidate(arg + 9);
 576                                 continue;
 577                         }
 578                         if (!strncmp(arg, "--until=", 8)) {
 579                                 revs->min_age = approxidate(arg + 8);
 580                                 continue;
 581                         }
 582                         if (!strcmp(arg, "--all")) {
 583                                 handle_all(revs, flags);
 584                                 continue;
 585                         }
 586                         if (!strcmp(arg, "--not")) {
 587                                 flags ^= UNINTERESTING;
 588                                 continue;
 589                         }
 590                         if (!strcmp(arg, "--default")) {
 591                                 if (++i >= argc)
 592                                         die("bad --default argument");
 593                                 def = argv[i];
 594                                 continue;
 595                         }
 596                         if (!strcmp(arg, "--topo-order")) {
 597                                 revs->topo_order = 1;
 598                                 continue;
 599                         }
 600                         if (!strcmp(arg, "--date-order")) {
 601                                 revs->lifo = 0;
 602                                 revs->topo_order = 1;
 603                                 continue;
 604                         }
 605                         if (!strcmp(arg, "--parents")) {
 606                                 revs->parents = 1;
 607                                 continue;
 608                         }
 609                         if (!strcmp(arg, "--dense")) {
 610                                 revs->dense = 1;
 611                                 continue;
 612                         }
 613                         if (!strcmp(arg, "--sparse")) {
 614                                 revs->dense = 0;
 615                                 continue;
 616                         }
 617                         if (!strcmp(arg, "--remove-empty")) {
 618                                 revs->remove_empty_trees = 1;
 619                                 continue;
 620                         }
 621                         if (!strcmp(arg, "--no-merges")) {
 622                                 revs->no_merges = 1;
 623                                 continue;
 624                         }
 625                         if (!strcmp(arg, "--boundary")) {
 626                                 revs->boundary = 1;
 627                                 continue;
 628                         }
 629                         if (!strcmp(arg, "--objects")) {
 630                                 revs->tag_objects = 1;
 631                                 revs->tree_objects = 1;
 632                                 revs->blob_objects = 1;
 633                                 continue;
 634                         }
 635                         if (!strcmp(arg, "--objects-edge")) {
 636                                 revs->tag_objects = 1;
 637                                 revs->tree_objects = 1;
 638                                 revs->blob_objects = 1;
 639                                 revs->edge_hint = 1;
 640                                 continue;
 641                         }
 642                         if (!strcmp(arg, "--unpacked")) {
 643                                 revs->unpacked = 1;
 644                                 continue;
 645                         }
 646                         *unrecognized++ = arg;
 647                         left++;
 648                         continue;
 649                 }
 650                 dotdot = strstr(arg, "..");
 651                 if (dotdot) {
 652                         unsigned char from_sha1[20];
 653                         const char *next = dotdot + 2;
 654                         const char *this = arg;
 655                         *dotdot = 0;
 656                         if (!*next)
 657                                 next = "HEAD";
 658                         if (dotdot == arg)
 659                                 this = "HEAD";
 660                         if (!get_sha1(this, from_sha1) &&
 661                             !get_sha1(next, sha1)) {
 662                                 struct commit *exclude;
 663                                 struct commit *include;
 664
 665                                 exclude = get_commit_reference(revs, this, from_sha1, flags ^ UNINTERESTING);
 666                                 include = get_commit_reference(revs, next, sha1, flags);
 667                                 if (!exclude || !include)
 668                                         die("Invalid revision range %s..%s", arg, next);
 669                                 add_one_commit(exclude, revs);
 670                                 add_one_commit(include, revs);
 671                                 continue;
 672                         }
 673                         *dotdot = '.';
 674                 }
 675                 local_flags = 0;
 676                 if (*arg == '^') {
 677                         local_flags = UNINTERESTING;
 678                         arg++;
 679                 }
 680                 if (get_sha1(arg, sha1) < 0) {
 681                         struct stat st;
 682                         int j;
 683
 684                         if (seen_dashdash || local_flags)
 685                                 die("bad revision '%s'", arg);
 686
 687                         /* If we didn't have a "--", all filenames must exist */
 688                         for (j = i; j < argc; j++) {
 689                                 if (lstat(argv[j], &st) < 0)
 690                                         die("'%s': %s", argv[j], strerror(errno));
 691                         }
 692                         revs->prune_data = get_pathspec(revs->prefix, argv + i);
 693                         break;
 694                 }
 695                 commit = get_commit_reference(revs, arg, sha1, flags ^ local_flags);
 696                 add_one_commit(commit, revs);
 697         }
 698         if (def && !revs->commits) {
 699                 unsigned char sha1[20];
 700                 struct commit *commit;
 701                 if (get_sha1(def, sha1) < 0)
 702                         die("bad default revision '%s'", def);
 703                 commit = get_commit_reference(revs, def, sha1, 0);
 704                 add_one_commit(commit, revs);
 705         }
 706
 707         if (revs->topo_order || revs->unpacked)
 708                 revs->limited = 1;
 709
 710         if (revs->prune_data) {
 711                 diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
 712                 revs->prune_fn = try_to_simplify_commit;
 713         }
 714
 715         return left;
 716 }
 717
 718 void prepare_revision_walk(struct rev_info *revs)
 719 {
 720         if (revs->no_walk)
 721                 return;
 722         sort_by_date(&revs->commits);
 723         if (revs->limited)
 724                 limit_list(revs);
 725         if (revs->topo_order)
 726                 sort_in_topological_order_fn(&revs->commits, revs->lifo,
 727                                              revs->topo_setter,
 728                                              revs->topo_getter);
 729 }
 730
 731 static int rewrite_one(struct rev_info *revs, struct commit **pp)
 732 {
 733         for (;;) {
 734                 struct commit *p = *pp;
 735                 if (!revs->limited)
 736                         add_parents_to_list(revs, p, &revs->commits);
 737                 if (p->object.flags & (TREECHANGE | UNINTERESTING))
 738                         return 0;
 739                 if (!p->parents)
 740                         return -1;
 741                 *pp = p->parents->item;
 742         }
 743 }
 744
 745 static void rewrite_parents(struct rev_info *revs, struct commit *commit)
 746 {
 747         struct commit_list **pp = &commit->parents;
 748         while (*pp) {
 749                 struct commit_list *parent = *pp;
 750                 if (rewrite_one(revs, &parent->item) < 0) {
 751                         *pp = parent->next;
 752                         continue;
 753                 }
 754                 pp = &parent->next;
 755         }
 756 }
 757
 758 struct commit *get_revision(struct rev_info *revs)
 759 {
 760         struct commit_list *list = revs->commits;
 761
 762         if (!list)
 763                 return NULL;
 764
 765         /* Check the max_count ... */
 766         switch (revs->max_count) {
 767         case -1:
 768                 break;
 769         case 0:
 770                 return NULL;
 771         default:
 772                 revs->max_count--;
 773         }
 774
 775         do {
 776                 struct commit *commit = revs->commits->item;
 777
 778                 revs->commits = revs->commits->next;
 779
 780                 /*
 781                  * If we haven't done the list limiting, we need to look at
 782                  * the parents here. We also need to do the date-based limiting
 783                  * that we'd otherwise have done in limit_list().
 784                  */
 785                 if (!revs->limited) {
 786                         if ((revs->unpacked &&
 787                              has_sha1_pack(commit->object.sha1)) ||
 788                             (revs->max_age != -1 &&
 789                              (commit->date < revs->max_age)))
 790                                 continue;
 791                         add_parents_to_list(revs, commit, &revs->commits);
 792                 }
 793                 if (commit->object.flags & SHOWN)
 794                         continue;
 795                 if (!(commit->object.flags & BOUNDARY) &&
 796                     (commit->object.flags & UNINTERESTING))
 797                         continue;
 798                 if (revs->min_age != -1 && (commit->date > revs->min_age))
 799                         continue;
 800                 if (revs->no_merges &&
 801                     commit->parents && commit->parents->next)
 802                         continue;
 803                 if (revs->prune_fn && revs->dense) {
 804                         if (!(commit->object.flags & TREECHANGE))
 805                                 continue;
 806                         if (revs->parents)
 807                                 rewrite_parents(revs, commit);
 808                 }
 809                 commit->object.flags |= SHOWN;
 810                 return commit;
 811         } while (revs->commits);
 812         return NULL;
 813 }