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