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 void show_commit_list(struct commit_list *list)
 218 {
 219         struct object_list *objects = NULL, **p = &objects, *pending;
 220         while (list) {
 221                 struct commit *commit = pop_most_recent_commit(&list, SEEN);
 222
 223                 p = process_tree(commit->tree, p, NULL, "");
 224                 if (process_commit(commit) == STOP)
 225                         break;
 226         }
 227         for (pending = revs.pending_objects; pending; pending = pending->next) {
 228                 struct object *obj = pending->item;
 229                 const char *name = pending->name;
 230                 if (obj->flags & (UNINTERESTING | SEEN))
 231                         continue;
 232                 if (obj->type == tag_type) {
 233                         obj->flags |= SEEN;
 234                         p = add_object(obj, p, NULL, name);
 235                         continue;
 236                 }
 237                 if (obj->type == tree_type) {
 238                         p = process_tree((struct tree *)obj, p, NULL, name);
 239                         continue;
 240                 }
 241                 if (obj->type == blob_type) {
 242                         p = process_blob((struct blob *)obj, p, NULL, name);
 243                         continue;
 244                 }
 245                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 246         }
 247         while (objects) {
 248                 /* An object with name "foo\n0000000..." can be used to
 249                  * confuse downstream git-pack-objects very badly.
 250                  */
 251                 const char *ep = strchr(objects->name, '\n');
 252                 if (ep) {
 253                         printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 254                                (int) (ep - objects->name),
 255                                objects->name);
 256                 }
 257                 else
 258                         printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 259                 objects = objects->next;
 260         }
 261 }
 262
 263 static int everybody_uninteresting(struct commit_list *orig)
 264 {
 265         struct commit_list *list = orig;
 266         while (list) {
 267                 struct commit *commit = list->item;
 268                 list = list->next;
 269                 if (commit->object.flags & UNINTERESTING)
 270                         continue;
 271                 return 0;
 272         }
 273         return 1;
 274 }
 275
 276 /*
 277  * This is a truly stupid algorithm, but it's only
 278  * used for bisection, and we just don't care enough.
 279  *
 280  * We care just barely enough to avoid recursing for
 281  * non-merge entries.
 282  */
 283 static int count_distance(struct commit_list *entry)
 284 {
 285         int nr = 0;
 286
 287         while (entry) {
 288                 struct commit *commit = entry->item;
 289                 struct commit_list *p;
 290
 291                 if (commit->object.flags & (UNINTERESTING | COUNTED))
 292                         break;
 293                 if (!revs.paths || (commit->object.flags & TREECHANGE))
 294                         nr++;
 295                 commit->object.flags |= COUNTED;
 296                 p = commit->parents;
 297                 entry = p;
 298                 if (p) {
 299                         p = p->next;
 300                         while (p) {
 301                                 nr += count_distance(p);
 302                                 p = p->next;
 303                         }
 304                 }
 305         }
 306
 307         return nr;
 308 }
 309
 310 static void clear_distance(struct commit_list *list)
 311 {
 312         while (list) {
 313                 struct commit *commit = list->item;
 314                 commit->object.flags &= ~COUNTED;
 315                 list = list->next;
 316         }
 317 }
 318
 319 static struct commit_list *find_bisection(struct commit_list *list)
 320 {
 321         int nr, closest;
 322         struct commit_list *p, *best;
 323
 324         nr = 0;
 325         p = list;
 326         while (p) {
 327                 if (!revs.paths || (p->item->object.flags & TREECHANGE))
 328                         nr++;
 329                 p = p->next;
 330         }
 331         closest = 0;
 332         best = list;
 333
 334         for (p = list; p; p = p->next) {
 335                 int distance;
 336
 337                 if (revs.paths && !(p->item->object.flags & TREECHANGE))
 338                         continue;
 339
 340                 distance = count_distance(p);
 341                 clear_distance(list);
 342                 if (nr - distance < distance)
 343                         distance = nr - distance;
 344                 if (distance > closest) {
 345                         best = p;
 346                         closest = distance;
 347                 }
 348         }
 349         if (best)
 350                 best->next = NULL;
 351         return best;
 352 }
 353
 354 static void mark_edge_parents_uninteresting(struct commit *commit)
 355 {
 356         struct commit_list *parents;
 357
 358         for (parents = commit->parents; parents; parents = parents->next) {
 359                 struct commit *parent = parents->item;
 360                 if (!(parent->object.flags & UNINTERESTING))
 361                         continue;
 362                 mark_tree_uninteresting(parent->tree);
 363                 if (revs.edge_hint && !(parent->object.flags & SHOWN)) {
 364                         parent->object.flags |= SHOWN;
 365                         printf("-%s\n", sha1_to_hex(parent->object.sha1));
 366                 }
 367         }
 368 }
 369
 370 static void mark_edges_uninteresting(struct commit_list *list)
 371 {
 372         for ( ; list; list = list->next) {
 373                 struct commit *commit = list->item;
 374
 375                 if (commit->object.flags & UNINTERESTING) {
 376                         mark_tree_uninteresting(commit->tree);
 377                         continue;
 378                 }
 379                 mark_edge_parents_uninteresting(commit);
 380         }
 381 }
 382
 383 #define TREE_SAME       0
 384 #define TREE_NEW        1
 385 #define TREE_DIFFERENT  2
 386 static int tree_difference = TREE_SAME;
 387
 388 static void file_add_remove(struct diff_options *options,
 389                     int addremove, unsigned mode,
 390                     const unsigned char *sha1,
 391                     const char *base, const char *path)
 392 {
 393         int diff = TREE_DIFFERENT;
 394
 395         /*
 396          * Is it an add of a new file? It means that
 397          * the old tree didn't have it at all, so we
 398          * will turn "TREE_SAME" -> "TREE_NEW", but
 399          * leave any "TREE_DIFFERENT" alone (and if
 400          * it already was "TREE_NEW", we'll keep it
 401          * "TREE_NEW" of course).
 402          */
 403         if (addremove == '+') {
 404                 diff = tree_difference;
 405                 if (diff != TREE_SAME)
 406                         return;
 407                 diff = TREE_NEW;
 408         }
 409         tree_difference = diff;
 410 }
 411
 412 static void file_change(struct diff_options *options,
 413                  unsigned old_mode, unsigned new_mode,
 414                  const unsigned char *old_sha1,
 415                  const unsigned char *new_sha1,
 416                  const char *base, const char *path)
 417 {
 418         tree_difference = TREE_DIFFERENT;
 419 }
 420
 421 static struct diff_options diff_opt = {
 422         .recursive = 1,
 423         .add_remove = file_add_remove,
 424         .change = file_change,
 425 };
 426
 427 static int compare_tree(struct tree *t1, struct tree *t2)
 428 {
 429         if (!t1)
 430                 return TREE_NEW;
 431         if (!t2)
 432                 return TREE_DIFFERENT;
 433         tree_difference = TREE_SAME;
 434         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
 435                 return TREE_DIFFERENT;
 436         return tree_difference;
 437 }
 438
 439 static int same_tree_as_empty(struct tree *t1)
 440 {
 441         int retval;
 442         void *tree;
 443         struct tree_desc empty, real;
 444
 445         if (!t1)
 446                 return 0;
 447
 448         tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
 449         if (!tree)
 450                 return 0;
 451         real.buf = tree;
 452
 453         empty.buf = "";
 454         empty.size = 0;
 455
 456         tree_difference = 0;
 457         retval = diff_tree(&empty, &real, "", &diff_opt);
 458         free(tree);
 459
 460         return retval >= 0 && !tree_difference;
 461 }
 462
 463 static void try_to_simplify_commit(struct commit *commit)
 464 {
 465         struct commit_list **pp, *parent;
 466
 467         if (!commit->tree)
 468                 return;
 469
 470         if (!commit->parents) {
 471                 if (!same_tree_as_empty(commit->tree))
 472                         commit->object.flags |= TREECHANGE;
 473                 return;
 474         }
 475
 476         pp = &commit->parents;
 477         while ((parent = *pp) != NULL) {
 478                 struct commit *p = parent->item;
 479
 480                 if (p->object.flags & UNINTERESTING) {
 481                         pp = &parent->next;
 482                         continue;
 483                 }
 484
 485                 parse_commit(p);
 486                 switch (compare_tree(p->tree, commit->tree)) {
 487                 case TREE_SAME:
 488                         parent->next = NULL;
 489                         commit->parents = parent;
 490                         return;
 491
 492                 case TREE_NEW:
 493                         if (revs.remove_empty_trees && same_tree_as_empty(p->tree)) {
 494                                 *pp = parent->next;
 495                                 continue;
 496                         }
 497                 /* fallthrough */
 498                 case TREE_DIFFERENT:
 499                         pp = &parent->next;
 500                         continue;
 501                 }
 502                 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 503         }
 504         commit->object.flags |= TREECHANGE;
 505 }
 506
 507 static void add_parents_to_list(struct commit *commit, struct commit_list **list)
 508 {
 509         struct commit_list *parent = commit->parents;
 510
 511         /*
 512          * If the commit is uninteresting, don't try to
 513          * prune parents - we want the maximal uninteresting
 514          * set.
 515          *
 516          * Normally we haven't parsed the parent
 517          * yet, so we won't have a parent of a parent
 518          * here. However, it may turn out that we've
 519          * reached this commit some other way (where it
 520          * wasn't uninteresting), in which case we need
 521          * to mark its parents recursively too..
 522          */
 523         if (commit->object.flags & UNINTERESTING) {
 524                 while (parent) {
 525                         struct commit *p = parent->item;
 526                         parent = parent->next;
 527                         parse_commit(p);
 528                         p->object.flags |= UNINTERESTING;
 529                         if (p->parents)
 530                                 mark_parents_uninteresting(p);
 531                         if (p->object.flags & SEEN)
 532                                 continue;
 533                         p->object.flags |= SEEN;
 534                         insert_by_date(p, list);
 535                 }
 536                 return;
 537         }
 538
 539         /*
 540          * Ok, the commit wasn't uninteresting. Try to
 541          * simplify the commit history and find the parent
 542          * that has no differences in the path set if one exists.
 543          */
 544         if (revs.paths)
 545                 try_to_simplify_commit(commit);
 546
 547         parent = commit->parents;
 548         while (parent) {
 549                 struct commit *p = parent->item;
 550
 551                 parent = parent->next;
 552
 553                 parse_commit(p);
 554                 if (p->object.flags & SEEN)
 555                         continue;
 556                 p->object.flags |= SEEN;
 557                 insert_by_date(p, list);
 558         }
 559 }
 560
 561 static struct commit_list *limit_list(struct commit_list *list)
 562 {
 563         struct commit_list *newlist = NULL;
 564         struct commit_list **p = &newlist;
 565         while (list) {
 566                 struct commit_list *entry = list;
 567                 struct commit *commit = list->item;
 568                 struct object *obj = &commit->object;
 569
 570                 list = list->next;
 571                 free(entry);
 572
 573                 if (revs.max_age != -1 && (commit->date < revs.max_age))
 574                         obj->flags |= UNINTERESTING;
 575                 if (unpacked && has_sha1_pack(obj->sha1))
 576                         obj->flags |= UNINTERESTING;
 577                 add_parents_to_list(commit, &list);
 578                 if (obj->flags & UNINTERESTING) {
 579                         mark_parents_uninteresting(commit);
 580                         if (everybody_uninteresting(list))
 581                                 break;
 582                         continue;
 583                 }
 584                 if (revs.min_age != -1 && (commit->date > revs.min_age))
 585                         continue;
 586                 p = &commit_list_insert(commit, p)->next;
 587         }
 588         if (revs.tree_objects)
 589                 mark_edges_uninteresting(newlist);
 590         if (bisect_list)
 591                 newlist = find_bisection(newlist);
 592         return newlist;
 593 }
 594
 595 int main(int argc, const char **argv)
 596 {
 597         struct commit_list *list;
 598         int i, limited = 0;
 599
 600         argc = setup_revisions(argc, argv, &revs);
 601
 602         for (i = 1 ; i < argc; i++) {
 603                 const char *arg = argv[i];
 604
 605                 /* accept -<digit>, like traditilnal "head" */
 606                 if ((*arg == '-') && isdigit(arg[1])) {
 607                         revs.max_count = atoi(arg + 1);
 608                         continue;
 609                 }
 610                 if (!strcmp(arg, "-n")) {
 611                         if (++i >= argc)
 612                                 die("-n requires an argument");
 613                         revs.max_count = atoi(argv[i]);
 614                         continue;
 615                 }
 616                 if (!strncmp(arg,"-n",2)) {
 617                         revs.max_count = atoi(arg + 2);
 618                         continue;
 619                 }
 620                 if (!strcmp(arg, "--header")) {
 621                         verbose_header = 1;
 622                         continue;
 623                 }
 624                 if (!strcmp(arg, "--no-abbrev")) {
 625                         abbrev = 0;
 626                         continue;
 627                 }
 628                 if (!strncmp(arg, "--abbrev=", 9)) {
 629                         abbrev = strtoul(arg + 9, NULL, 10);
 630                         if (abbrev && abbrev < MINIMUM_ABBREV)
 631                                 abbrev = MINIMUM_ABBREV;
 632                         else if (40 < abbrev)
 633                                 abbrev = 40;
 634                         continue;
 635                 }
 636                 if (!strncmp(arg, "--pretty", 8)) {
 637                         commit_format = get_commit_format(arg+8);
 638                         verbose_header = 1;
 639                         hdr_termination = '\n';
 640                         if (commit_format == CMIT_FMT_ONELINE)
 641                                 commit_prefix = "";
 642                         else
 643                                 commit_prefix = "commit ";
 644                         continue;
 645                 }
 646                 if (!strncmp(arg, "--no-merges", 11)) {
 647                         no_merges = 1;
 648                         continue;
 649                 }
 650                 if (!strcmp(arg, "--parents")) {
 651                         show_parents = 1;
 652                         continue;
 653                 }
 654                 if (!strcmp(arg, "--bisect")) {
 655                         bisect_list = 1;
 656                         continue;
 657                 }
 658                 if (!strcmp(arg, "--unpacked")) {
 659                         unpacked = 1;
 660                         limited = 1;
 661                         continue;
 662                 }
 663                 if (!strcmp(arg, "--merge-order")) {
 664                         merge_order = 1;
 665                         continue;
 666                 }
 667                 if (!strcmp(arg, "--show-breaks")) {
 668                         show_breaks = 1;
 669                         continue;
 670                 }
 671                 usage(rev_list_usage);
 672
 673         }
 674
 675         list = revs.commits;
 676         if (list)
 677                 limited = 1;
 678
 679         if (revs.topo_order)
 680                 limited = 1;
 681
 682         if (!list &&
 683             (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) && !revs.pending_objects))
 684                 usage(rev_list_usage);
 685
 686         if (revs.paths) {
 687                 limited = 1;
 688                 diff_tree_setup_paths(revs.paths);
 689         }
 690         if (revs.max_age != -1 || revs.min_age != -1)
 691                 limited = 1;
 692
 693         save_commit_buffer = verbose_header;
 694         track_object_refs = 0;
 695
 696         if (!merge_order) {
 697                 sort_by_date(&list);
 698                 if (list && !limited && revs.max_count == 1 &&
 699                     !revs.tag_objects && !revs.tree_objects && !revs.blob_objects) {
 700                         show_commit(list->item);
 701                         return 0;
 702                 }
 703                 if (limited)
 704                         list = limit_list(list);
 705                 if (revs.topo_order)
 706                         sort_in_topological_order(&list, revs.lifo);
 707                 show_commit_list(list);
 708         } else {
 709 #ifndef NO_OPENSSL
 710                 if (sort_list_in_merge_order(list, &process_commit)) {
 711                         die("merge order sort failed\n");
 712                 }
 713 #else
 714                 die("merge order sort unsupported, OpenSSL not linked");
 715 #endif
 716         }
 717
 718         return 0;
 719 }