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 #include "revision.h"
  10
  11 /* bits #0 and #1 in revision.h */
  12
  13 #define COUNTED         (1u << 2)
  14 #define SHOWN           (1u << 3)
  15 #define TREECHANGE      (1u << 4)
  16 #define TMP_MARK        (1u << 5) /* for isolated cases; clean after use */
  17
  18 static const char rev_list_usage[] =
  19 "git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
  20 "  limiting output:\n"
  21 "    --max-count=nr\n"
  22 "    --max-age=epoch\n"
  23 "    --min-age=epoch\n"
  24 "    --sparse\n"
  25 "    --no-merges\n"
  26 "    --remove-empty\n"
  27 "    --all\n"
  28 "  ordering output:\n"
  29 "    --merge-order [ --show-breaks ]\n"
  30 "    --topo-order\n"
  31 "    --date-order\n"
  32 "  formatting output:\n"
  33 "    --parents\n"
  34 "    --objects | --objects-edge\n"
  35 "    --unpacked\n"
  36 "    --header | --pretty\n"
  37 "    --abbrev=nr | --no-abbrev\n"
  38 "  special purpose:\n"
  39 "    --bisect"
  40 ;
  41
  42 struct rev_info revs;
  43
  44 static int unpacked = 0;
  45 static int bisect_list = 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 enum cmit_fmt commit_format = CMIT_FMT_RAW;
  52 static int merge_order = 0;
  53 static int show_breaks = 0;
  54 static int stop_traversal = 0;
  55 static int no_merges = 0;
  56
  57 static void show_commit(struct commit *commit)
  58 {
  59         commit->object.flags |= SHOWN;
  60         if (show_breaks) {
  61                 commit_prefix = "| ";
  62                 if (commit->object.flags & DISCONTINUITY) {
  63                         commit_prefix = "^ ";
  64                 } else if (commit->object.flags & BOUNDARY) {
  65                         commit_prefix = "= ";
  66                 }
  67         }
  68         printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
  69         if (show_parents) {
  70                 struct commit_list *parents = commit->parents;
  71                 while (parents) {
  72                         struct object *o = &(parents->item->object);
  73                         parents = parents->next;
  74                         if (o->flags & TMP_MARK)
  75                                 continue;
  76                         printf(" %s", sha1_to_hex(o->sha1));
  77                         o->flags |= TMP_MARK;
  78                 }
  79                 /* TMP_MARK is a general purpose flag that can
  80                  * be used locally, but the user should clean
  81                  * things up after it is done with them.
  82                  */
  83                 for (parents = commit->parents;
  84                      parents;
  85                      parents = parents->next)
  86                         parents->item->object.flags &= ~TMP_MARK;
  87         }
  88         if (commit_format == CMIT_FMT_ONELINE)
  89                 putchar(' ');
  90         else
  91                 putchar('\n');
  92
  93         if (verbose_header) {
  94                 static char pretty_header[16384];
  95                 pretty_print_commit(commit_format, commit, ~0, pretty_header, sizeof(pretty_header), abbrev);
  96                 printf("%s%c", pretty_header, hdr_termination);
  97         }
  98         fflush(stdout);
  99 }
 100
 101 static int rewrite_one(struct commit **pp)
 102 {
 103         for (;;) {
 104                 struct commit *p = *pp;
 105                 if (p->object.flags & (TREECHANGE | UNINTERESTING))
 106                         return 0;
 107                 if (!p->parents)
 108                         return -1;
 109                 *pp = p->parents->item;
 110         }
 111 }
 112
 113 static void rewrite_parents(struct commit *commit)
 114 {
 115         struct commit_list **pp = &commit->parents;
 116         while (*pp) {
 117                 struct commit_list *parent = *pp;
 118                 if (rewrite_one(&parent->item) < 0) {
 119                         *pp = parent->next;
 120                         continue;
 121                 }
 122                 pp = &parent->next;
 123         }
 124 }
 125
 126 static int filter_commit(struct commit * commit)
 127 {
 128         if (stop_traversal && (commit->object.flags & BOUNDARY))
 129                 return STOP;
 130         if (commit->object.flags & (UNINTERESTING|SHOWN))
 131                 return CONTINUE;
 132         if (revs.min_age != -1 && (commit->date > revs.min_age))
 133                 return CONTINUE;
 134         if (revs.max_age != -1 && (commit->date < revs.max_age)) {
 135                 stop_traversal=1;
 136                 return CONTINUE;
 137         }
 138         if (no_merges && (commit->parents && commit->parents->next))
 139                 return CONTINUE;
 140         if (revs.paths && revs.dense) {
 141                 if (!(commit->object.flags & TREECHANGE))
 142                         return CONTINUE;
 143                 rewrite_parents(commit);
 144         }
 145         return DO;
 146 }
 147
 148 static int process_commit(struct commit * commit)
 149 {
 150         int action=filter_commit(commit);
 151
 152         if (action == STOP) {
 153                 return STOP;
 154         }
 155
 156         if (action == CONTINUE) {
 157                 return CONTINUE;
 158         }
 159
 160         if (revs.max_count != -1 && !revs.max_count--)
 161                 return STOP;
 162
 163         show_commit(commit);
 164
 165         return CONTINUE;
 166 }
 167
 168 static struct object_list **process_blob(struct blob *blob,
 169                                          struct object_list **p,
 170                                          struct name_path *path,
 171                                          const char *name)
 172 {
 173         struct object *obj = &blob->object;
 174
 175         if (!revs.blob_objects)
 176                 return p;
 177         if (obj->flags & (UNINTERESTING | SEEN))
 178                 return p;
 179         obj->flags |= SEEN;
 180         return add_object(obj, p, path, name);
 181 }
 182
 183 static struct object_list **process_tree(struct tree *tree,
 184                                          struct object_list **p,
 185                                          struct name_path *path,
 186                                          const char *name)
 187 {
 188         struct object *obj = &tree->object;
 189         struct tree_entry_list *entry;
 190         struct name_path me;
 191
 192         if (!revs.tree_objects)
 193                 return p;
 194         if (obj->flags & (UNINTERESTING | SEEN))
 195                 return p;
 196         if (parse_tree(tree) < 0)
 197                 die("bad tree object %s", sha1_to_hex(obj->sha1));
 198         obj->flags |= SEEN;
 199         p = add_object(obj, p, path, name);
 200         me.up = path;
 201         me.elem = name;
 202         me.elem_len = strlen(name);
 203         entry = tree->entries;
 204         tree->entries = NULL;
 205         while (entry) {
 206                 struct tree_entry_list *next = entry->next;
 207                 if (entry->directory)
 208                         p = process_tree(entry->item.tree, p, &me, entry->name);
 209                 else
 210                         p = process_blob(entry->item.blob, p, &me, entry->name);
 211                 free(entry);
 212                 entry = next;
 213         }
 214         return p;
 215 }
 216
 217 static struct object_list *pending_objects = NULL;
 218
 219 static void show_commit_list(struct commit_list *list)
 220 {
 221         struct object_list *objects = NULL, **p = &objects, *pending;
 222         while (list) {
 223                 struct commit *commit = pop_most_recent_commit(&list, SEEN);
 224
 225                 p = process_tree(commit->tree, p, NULL, "");
 226                 if (process_commit(commit) == STOP)
 227                         break;
 228         }
 229         for (pending = pending_objects; pending; pending = pending->next) {
 230                 struct object *obj = pending->item;
 231                 const char *name = pending->name;
 232                 if (obj->flags & (UNINTERESTING | SEEN))
 233                         continue;
 234                 if (obj->type == tag_type) {
 235                         obj->flags |= SEEN;
 236                         p = add_object(obj, p, NULL, name);
 237                         continue;
 238                 }
 239                 if (obj->type == tree_type) {
 240                         p = process_tree((struct tree *)obj, p, NULL, name);
 241                         continue;
 242                 }
 243                 if (obj->type == blob_type) {
 244                         p = process_blob((struct blob *)obj, p, NULL, name);
 245                         continue;
 246                 }
 247                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 248         }
 249         while (objects) {
 250                 /* An object with name "foo\n0000000..." can be used to
 251                  * confuse downstream git-pack-objects very badly.
 252                  */
 253                 const char *ep = strchr(objects->name, '\n');
 254                 if (ep) {
 255                         printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 256                                (int) (ep - objects->name),
 257                                objects->name);
 258                 }
 259                 else
 260                         printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 261                 objects = objects->next;
 262         }
 263 }
 264
 265 static int everybody_uninteresting(struct commit_list *orig)
 266 {
 267         struct commit_list *list = orig;
 268         while (list) {
 269                 struct commit *commit = list->item;
 270                 list = list->next;
 271                 if (commit->object.flags & UNINTERESTING)
 272                         continue;
 273                 return 0;
 274         }
 275         return 1;
 276 }
 277
 278 /*
 279  * This is a truly stupid algorithm, but it's only
 280  * used for bisection, and we just don't care enough.
 281  *
 282  * We care just barely enough to avoid recursing for
 283  * non-merge entries.
 284  */
 285 static int count_distance(struct commit_list *entry)
 286 {
 287         int nr = 0;
 288
 289         while (entry) {
 290                 struct commit *commit = entry->item;
 291                 struct commit_list *p;
 292
 293                 if (commit->object.flags & (UNINTERESTING | COUNTED))
 294                         break;
 295                 if (!revs.paths || (commit->object.flags & TREECHANGE))
 296                         nr++;
 297                 commit->object.flags |= COUNTED;
 298                 p = commit->parents;
 299                 entry = p;
 300                 if (p) {
 301                         p = p->next;
 302                         while (p) {
 303                                 nr += count_distance(p);
 304                                 p = p->next;
 305                         }
 306                 }
 307         }
 308
 309         return nr;
 310 }
 311
 312 static void clear_distance(struct commit_list *list)
 313 {
 314         while (list) {
 315                 struct commit *commit = list->item;
 316                 commit->object.flags &= ~COUNTED;
 317                 list = list->next;
 318         }
 319 }
 320
 321 static struct commit_list *find_bisection(struct commit_list *list)
 322 {
 323         int nr, closest;
 324         struct commit_list *p, *best;
 325
 326         nr = 0;
 327         p = list;
 328         while (p) {
 329                 if (!revs.paths || (p->item->object.flags & TREECHANGE))
 330                         nr++;
 331                 p = p->next;
 332         }
 333         closest = 0;
 334         best = list;
 335
 336         for (p = list; p; p = p->next) {
 337                 int distance;
 338
 339                 if (revs.paths && !(p->item->object.flags & TREECHANGE))
 340                         continue;
 341
 342                 distance = count_distance(p);
 343                 clear_distance(list);
 344                 if (nr - distance < distance)
 345                         distance = nr - distance;
 346                 if (distance > closest) {
 347                         best = p;
 348                         closest = distance;
 349                 }
 350         }
 351         if (best)
 352                 best->next = NULL;
 353         return best;
 354 }
 355
 356 static void mark_edge_parents_uninteresting(struct commit *commit)
 357 {
 358         struct commit_list *parents;
 359
 360         for (parents = commit->parents; parents; parents = parents->next) {
 361                 struct commit *parent = parents->item;
 362                 if (!(parent->object.flags & UNINTERESTING))
 363                         continue;
 364                 mark_tree_uninteresting(parent->tree);
 365                 if (revs.edge_hint && !(parent->object.flags & SHOWN)) {
 366                         parent->object.flags |= SHOWN;
 367                         printf("-%s\n", sha1_to_hex(parent->object.sha1));
 368                 }
 369         }
 370 }
 371
 372 static void mark_edges_uninteresting(struct commit_list *list)
 373 {
 374         for ( ; list; list = list->next) {
 375                 struct commit *commit = list->item;
 376
 377                 if (commit->object.flags & UNINTERESTING) {
 378                         mark_tree_uninteresting(commit->tree);
 379                         continue;
 380                 }
 381                 mark_edge_parents_uninteresting(commit);
 382         }
 383 }
 384
 385 #define TREE_SAME       0
 386 #define TREE_NEW        1
 387 #define TREE_DIFFERENT  2
 388 static int tree_difference = TREE_SAME;
 389
 390 static void file_add_remove(struct diff_options *options,
 391                     int addremove, unsigned mode,
 392                     const unsigned char *sha1,
 393                     const char *base, const char *path)
 394 {
 395         int diff = TREE_DIFFERENT;
 396
 397         /*
 398          * Is it an add of a new file? It means that
 399          * the old tree didn't have it at all, so we
 400          * will turn "TREE_SAME" -> "TREE_NEW", but
 401          * leave any "TREE_DIFFERENT" alone (and if
 402          * it already was "TREE_NEW", we'll keep it
 403          * "TREE_NEW" of course).
 404          */
 405         if (addremove == '+') {
 406                 diff = tree_difference;
 407                 if (diff != TREE_SAME)
 408                         return;
 409                 diff = TREE_NEW;
 410         }
 411         tree_difference = diff;
 412 }
 413
 414 static void file_change(struct diff_options *options,
 415                  unsigned old_mode, unsigned new_mode,
 416                  const unsigned char *old_sha1,
 417                  const unsigned char *new_sha1,
 418                  const char *base, const char *path)
 419 {
 420         tree_difference = TREE_DIFFERENT;
 421 }
 422
 423 static struct diff_options diff_opt = {
 424         .recursive = 1,
 425         .add_remove = file_add_remove,
 426         .change = file_change,
 427 };
 428
 429 static int compare_tree(struct tree *t1, struct tree *t2)
 430 {
 431         if (!t1)
 432                 return TREE_NEW;
 433         if (!t2)
 434                 return TREE_DIFFERENT;
 435         tree_difference = TREE_SAME;
 436         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 437                 return TREE_DIFFERENT;
 438         return tree_difference;
 439 }
 440
 441 static int same_tree_as_empty(struct tree *t1)
 442 {
 443         int retval;
 444         void *tree;
 445         struct tree_desc empty, real;
 446
 447         if (!t1)
 448                 return 0;
 449
 450         tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 451         if (!tree)
 452                 return 0;
 453         real.buf = tree;
 454
 455         empty.buf = "";
 456         empty.size = 0;
 457
 458         tree_difference = 0;
 459         retval = diff_tree(&empty, &real, "", &diff_opt);
 460         free(tree);
 461
 462         return retval >= 0 && !tree_difference;
 463 }
 464
 465 static void try_to_simplify_commit(struct commit *commit)
 466 {
 467         struct commit_list **pp, *parent;
 468
 469         if (!commit->tree)
 470                 return;
 471
 472         if (!commit->parents) {
 473                 if (!same_tree_as_empty(commit->tree))
 474                         commit->object.flags |= TREECHANGE;
 475                 return;
 476         }
 477
 478         pp = &commit->parents;
 479         while ((parent = *pp) != NULL) {
 480                 struct commit *p = parent->item;
 481
 482                 if (p->object.flags & UNINTERESTING) {
 483                         pp = &parent->next;
 484                         continue;
 485                 }
 486
 487                 parse_commit(p);
 488                 switch (compare_tree(p->tree, commit->tree)) {
 489                 case TREE_SAME:
 490                         parent->next = NULL;
 491                         commit->parents = parent;
 492                         return;
 493
 494                 case TREE_NEW:
 495                         if (revs.remove_empty_trees && same_tree_as_empty(p->tree)) {
 496                                 *pp = parent->next;
 497                                 continue;
 498                         }
 499                 /* fallthrough */
 500                 case TREE_DIFFERENT:
 501                         pp = &parent->next;
 502                         continue;
 503                 }
 504                 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 505         }
 506         commit->object.flags |= TREECHANGE;
 507 }
 508
 509 static void add_parents_to_list(struct commit *commit, struct commit_list **list)
 510 {
 511         struct commit_list *parent = commit->parents;
 512
 513         /*
 514          * If the commit is uninteresting, don't try to
 515          * prune parents - we want the maximal uninteresting
 516          * set.
 517          *
 518          * Normally we haven't parsed the parent
 519          * yet, so we won't have a parent of a parent
 520          * here. However, it may turn out that we've
 521          * reached this commit some other way (where it
 522          * wasn't uninteresting), in which case we need
 523          * to mark its parents recursively too..
 524          */
 525         if (commit->object.flags & UNINTERESTING) {
 526                 while (parent) {
 527                         struct commit *p = parent->item;
 528                         parent = parent->next;
 529                         parse_commit(p);
 530                         p->object.flags |= UNINTERESTING;
 531                         if (p->parents)
 532                                 mark_parents_uninteresting(p);
 533                         if (p->object.flags & SEEN)
 534                                 continue;
 535                         p->object.flags |= SEEN;
 536                         insert_by_date(p, list);
 537                 }
 538                 return;
 539         }
 540
 541         /*
 542          * Ok, the commit wasn't uninteresting. Try to
 543          * simplify the commit history and find the parent
 544          * that has no differences in the path set if one exists.
 545          */
 546         if (revs.paths)
 547                 try_to_simplify_commit(commit);
 548
 549         parent = commit->parents;
 550         while (parent) {
 551                 struct commit *p = parent->item;
 552
 553                 parent = parent->next;
 554
 555                 parse_commit(p);
 556                 if (p->object.flags & SEEN)
 557                         continue;
 558                 p->object.flags |= SEEN;
 559                 insert_by_date(p, list);
 560         }
 561 }
 562
 563 static struct commit_list *limit_list(struct commit_list *list)
 564 {
 565         struct commit_list *newlist = NULL;
 566         struct commit_list **p = &newlist;
 567         while (list) {
 568                 struct commit_list *entry = list;
 569                 struct commit *commit = list->item;
 570                 struct object *obj = &commit->object;
 571
 572                 list = list->next;
 573                 free(entry);
 574
 575                 if (revs.max_age != -1 && (commit->date < revs.max_age))
 576                         obj->flags |= UNINTERESTING;
 577                 if (unpacked && has_sha1_pack(obj->sha1))
 578                         obj->flags |= UNINTERESTING;
 579                 add_parents_to_list(commit, &list);
 580                 if (obj->flags & UNINTERESTING) {
 581                         mark_parents_uninteresting(commit);
 582                         if (everybody_uninteresting(list))
 583                                 break;
 584                         continue;
 585                 }
 586                 if (revs.min_age != -1 && (commit->date > revs.min_age))
 587                         continue;
 588                 p = &commit_list_insert(commit, p)->next;
 589         }
 590         if (revs.tree_objects)
 591                 mark_edges_uninteresting(newlist);
 592         if (bisect_list)
 593                 newlist = find_bisection(newlist);
 594         return newlist;
 595 }
 596
 597 int main(int argc, const char **argv)
 598 {
 599         struct commit_list *list;
 600         int i, limited = 0;
 601
 602         argc = setup_revisions(argc, argv, &revs);
 603
 604         for (i = 1 ; i < argc; i++) {
 605                 const char *arg = argv[i];
 606
 607                 /* accept -<digit>, like traditilnal "head" */
 608                 if ((*arg == '-') && isdigit(arg[1])) {
 609                         revs.max_count = atoi(arg + 1);
 610                         continue;
 611                 }
 612                 if (!strcmp(arg, "-n")) {
 613                         if (++i >= argc)
 614                                 die("-n requires an argument");
 615                         revs.max_count = atoi(argv[i]);
 616                         continue;
 617                 }
 618                 if (!strncmp(arg,"-n",2)) {
 619                         revs.max_count = atoi(arg + 2);
 620                         continue;
 621                 }
 622                 if (!strcmp(arg, "--header")) {
 623                         verbose_header = 1;
 624                         continue;
 625                 }
 626                 if (!strcmp(arg, "--no-abbrev")) {
 627                         abbrev = 0;
 628                         continue;
 629                 }
 630                 if (!strncmp(arg, "--abbrev=", 9)) {
 631                         abbrev = strtoul(arg + 9, NULL, 10);
 632                         if (abbrev && abbrev < MINIMUM_ABBREV)
 633                                 abbrev = MINIMUM_ABBREV;
 634                         else if (40 < abbrev)
 635                                 abbrev = 40;
 636                         continue;
 637                 }
 638                 if (!strncmp(arg, "--pretty", 8)) {
 639                         commit_format = get_commit_format(arg+8);
 640                         verbose_header = 1;
 641                         hdr_termination = '\n';
 642                         if (commit_format == CMIT_FMT_ONELINE)
 643                                 commit_prefix = "";
 644                         else
 645                                 commit_prefix = "commit ";
 646                         continue;
 647                 }
 648                 if (!strncmp(arg, "--no-merges", 11)) {
 649                         no_merges = 1;
 650                         continue;
 651                 }
 652                 if (!strcmp(arg, "--parents")) {
 653                         show_parents = 1;
 654                         continue;
 655                 }
 656                 if (!strcmp(arg, "--bisect")) {
 657                         bisect_list = 1;
 658                         continue;
 659                 }
 660                 if (!strcmp(arg, "--unpacked")) {
 661                         unpacked = 1;
 662                         limited = 1;
 663                         continue;
 664                 }
 665                 if (!strcmp(arg, "--merge-order")) {
 666                         merge_order = 1;
 667                         continue;
 668                 }
 669                 if (!strcmp(arg, "--show-breaks")) {
 670                         show_breaks = 1;
 671                         continue;
 672                 }
 673                 usage(rev_list_usage);
 674
 675         }
 676
 677         list = revs.commits;
 678         if (list && list->next)
 679                 limited = 1;
 680
 681         if (revs.topo_order)
 682                 limited = 1;
 683
 684         if (!list &&
 685             (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) && !revs.pending_objects))
 686                 usage(rev_list_usage);
 687
 688         if (revs.paths) {
 689                 limited = 1;
 690                 diff_tree_setup_paths(revs.paths);
 691         }
 692         if (revs.max_age || revs.min_age)
 693                 limited = 1;
 694
 695         save_commit_buffer = verbose_header;
 696         track_object_refs = 0;
 697
 698         if (!merge_order) {
 699                 sort_by_date(&list);
 700                 if (list && !limited && revs.max_count == 1 &&
 701                     !revs.tag_objects && !revs.tree_objects && !revs.blob_objects) {
 702                         show_commit(list->item);
 703                         return 0;
 704                 }
 705                 if (limited)
 706                         list = limit_list(list);
 707                 if (revs.topo_order)
 708                         sort_in_topological_order(&list, revs.lifo);
 709                 show_commit_list(list);
 710         } else {
 711 #ifndef NO_OPENSSL
 712                 if (sort_list_in_merge_order(list, &process_commit)) {
 713                         die("merge order sort failed\n");
 714                 }
 715 #else
 716                 die("merge order sort unsupported, OpenSSL not linked");
 717 #endif
 718         }
 719
 720         return 0;
 721 }