shallow.c

   1 #include "cache.h"
   2 #include "tempfile.h"
   3 #include "lockfile.h"
   4 #include "commit.h"
   5 #include "tag.h"
   6 #include "pkt-line.h"
   7 #include "remote.h"
   8 #include "refs.h"
   9 #include "sha1-array.h"
  10 #include "diff.h"
  11 #include "revision.h"
  12 #include "commit-slab.h"
  13 #include "revision.h"
  14 #include "list-objects.h"
  15
  16 static int is_shallow = -1;
  17 static struct stat_validity shallow_stat;
  18 static char *alternate_shallow_file;
  19
  20 void set_alternate_shallow_file(const char *path, int override)
  21 {
  22         if (is_shallow != -1)
  23                 die("BUG: is_repository_shallow must not be called before set_alternate_shallow_file");
  24         if (alternate_shallow_file && !override)
  25                 return;
  26         free(alternate_shallow_file);
  27         alternate_shallow_file = xstrdup_or_null(path);
  28 }
  29
  30 int register_shallow(const struct object_id *oid)
  31 {
  32         struct commit_graft *graft =
  33                 xmalloc(sizeof(struct commit_graft));
  34         struct commit *commit = lookup_commit(oid);
  35
  36         oidcpy(&graft->oid, oid);
  37         graft->nr_parent = -1;
  38         if (commit && commit->object.parsed)
  39                 commit->parents = NULL;
  40         return register_commit_graft(graft, 0);
  41 }
  42
  43 int is_repository_shallow(void)
  44 {
  45         FILE *fp;
  46         char buf[1024];
  47         const char *path = alternate_shallow_file;
  48
  49         if (is_shallow >= 0)
  50                 return is_shallow;
  51
  52         if (!path)
  53                 path = git_path_shallow();
  54         /*
  55          * fetch-pack sets '--shallow-file ""' as an indicator that no
  56          * shallow file should be used. We could just open it and it
  57          * will likely fail. But let's do an explicit check instead.
  58          */
  59         if (!*path || (fp = fopen(path, "r")) == NULL) {
  60                 stat_validity_clear(&shallow_stat);
  61                 is_shallow = 0;
  62                 return is_shallow;
  63         }
  64         stat_validity_update(&shallow_stat, fileno(fp));
  65         is_shallow = 1;
  66
  67         while (fgets(buf, sizeof(buf), fp)) {
  68                 struct object_id oid;
  69                 if (get_oid_hex(buf, &oid))
  70                         die("bad shallow line: %s", buf);
  71                 register_shallow(&oid);
  72         }
  73         fclose(fp);
  74         return is_shallow;
  75 }
  76
  77 struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
  78                 int shallow_flag, int not_shallow_flag)
  79 {
  80         int i = 0, cur_depth = 0;
  81         struct commit_list *result = NULL;
  82         struct object_array stack = OBJECT_ARRAY_INIT;
  83         struct commit *commit = NULL;
  84         struct commit_graft *graft;
  85
  86         while (commit || i < heads->nr || stack.nr) {
  87                 struct commit_list *p;
  88                 if (!commit) {
  89                         if (i < heads->nr) {
  90                                 commit = (struct commit *)
  91                                         deref_tag(heads->objects[i++].item, NULL, 0);
  92                                 if (!commit || commit->object.type != OBJ_COMMIT) {
  93                                         commit = NULL;
  94                                         continue;
  95                                 }
  96                                 if (!commit->util)
  97                                         commit->util = xmalloc(sizeof(int));
  98                                 *(int *)commit->util = 0;
  99                                 cur_depth = 0;
 100                         } else {
 101                                 commit = (struct commit *)
 102                                         object_array_pop(&stack);
 103                                 cur_depth = *(int *)commit->util;
 104                         }
 105                 }
 106                 parse_commit_or_die(commit);
 107                 cur_depth++;
 108                 if ((depth != INFINITE_DEPTH && cur_depth >= depth) ||
 109                     (is_repository_shallow() && !commit->parents &&
 110                      (graft = lookup_commit_graft(&commit->object.oid)) != NULL &&
 111                      graft->nr_parent < 0)) {
 112                         commit_list_insert(commit, &result);
 113                         commit->object.flags |= shallow_flag;
 114                         commit = NULL;
 115                         continue;
 116                 }
 117                 commit->object.flags |= not_shallow_flag;
 118                 for (p = commit->parents, commit = NULL; p; p = p->next) {
 119                         if (!p->item->util) {
 120                                 int *pointer = xmalloc(sizeof(int));
 121                                 p->item->util = pointer;
 122                                 *pointer =  cur_depth;
 123                         } else {
 124                                 int *pointer = p->item->util;
 125                                 if (cur_depth >= *pointer)
 126                                         continue;
 127                                 *pointer = cur_depth;
 128                         }
 129                         if (p->next)
 130                                 add_object_array(&p->item->object,
 131                                                 NULL, &stack);
 132                         else {
 133                                 commit = p->item;
 134                                 cur_depth = *(int *)commit->util;
 135                         }
 136                 }
 137         }
 138
 139         return result;
 140 }
 141
 142 static void show_commit(struct commit *commit, void *data)
 143 {
 144         commit_list_insert(commit, data);
 145 }
 146
 147 /*
 148  * Given rev-list arguments, run rev-list. All reachable commits
 149  * except border ones are marked with not_shallow_flag. Border commits
 150  * are marked with shallow_flag. The list of border/shallow commits
 151  * are also returned.
 152  */
 153 struct commit_list *get_shallow_commits_by_rev_list(int ac, const char **av,
 154                                                     int shallow_flag,
 155                                                     int not_shallow_flag)
 156 {
 157         struct commit_list *result = NULL, *p;
 158         struct commit_list *not_shallow_list = NULL;
 159         struct rev_info revs;
 160         int both_flags = shallow_flag | not_shallow_flag;
 161
 162         /*
 163          * SHALLOW (excluded) and NOT_SHALLOW (included) should not be
 164          * set at this point. But better be safe than sorry.
 165          */
 166         clear_object_flags(both_flags);
 167
 168         is_repository_shallow(); /* make sure shallows are read */
 169
 170         init_revisions(&revs, NULL);
 171         save_commit_buffer = 0;
 172         setup_revisions(ac, av, &revs, NULL);
 173
 174         if (prepare_revision_walk(&revs))
 175                 die("revision walk setup failed");
 176         traverse_commit_list(&revs, show_commit, NULL, &not_shallow_list);
 177
 178         /* Mark all reachable commits as NOT_SHALLOW */
 179         for (p = not_shallow_list; p; p = p->next)
 180                 p->item->object.flags |= not_shallow_flag;
 181
 182         /*
 183          * mark border commits SHALLOW + NOT_SHALLOW.
 184          * We cannot clear NOT_SHALLOW right now. Imagine border
 185          * commit A is processed first, then commit B, whose parent is
 186          * A, later. If NOT_SHALLOW on A is cleared at step 1, B
 187          * itself is considered border at step 2, which is incorrect.
 188          */
 189         for (p = not_shallow_list; p; p = p->next) {
 190                 struct commit *c = p->item;
 191                 struct commit_list *parent;
 192
 193                 if (parse_commit(c))
 194                         die("unable to parse commit %s",
 195                             oid_to_hex(&c->object.oid));
 196
 197                 for (parent = c->parents; parent; parent = parent->next)
 198                         if (!(parent->item->object.flags & not_shallow_flag)) {
 199                                 c->object.flags |= shallow_flag;
 200                                 commit_list_insert(c, &result);
 201                                 break;
 202                         }
 203         }
 204         free_commit_list(not_shallow_list);
 205
 206         /*
 207          * Now we can clean up NOT_SHALLOW on border commits. Having
 208          * both flags set can confuse the caller.
 209          */
 210         for (p = result; p; p = p->next) {
 211                 struct object *o = &p->item->object;
 212                 if ((o->flags & both_flags) == both_flags)
 213                         o->flags &= ~not_shallow_flag;
 214         }
 215         return result;
 216 }
 217
 218 static void check_shallow_file_for_update(void)
 219 {
 220         if (is_shallow == -1)
 221                 die("BUG: shallow must be initialized by now");
 222
 223         if (!stat_validity_check(&shallow_stat, git_path_shallow()))
 224                 die("shallow file has changed since we read it");
 225 }
 226
 227 #define SEEN_ONLY 1
 228 #define VERBOSE   2
 229
 230 struct write_shallow_data {
 231         struct strbuf *out;
 232         int use_pack_protocol;
 233         int count;
 234         unsigned flags;
 235 };
 236
 237 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
 238 {
 239         struct write_shallow_data *data = cb_data;
 240         const char *hex = oid_to_hex(&graft->oid);
 241         if (graft->nr_parent != -1)
 242                 return 0;
 243         if (data->flags & SEEN_ONLY) {
 244                 struct commit *c = lookup_commit(&graft->oid);
 245                 if (!c || !(c->object.flags & SEEN)) {
 246                         if (data->flags & VERBOSE)
 247                                 printf("Removing %s from .git/shallow\n",
 248                                        oid_to_hex(&c->object.oid));
 249                         return 0;
 250                 }
 251         }
 252         data->count++;
 253         if (data->use_pack_protocol)
 254                 packet_buf_write(data->out, "shallow %s", hex);
 255         else {
 256                 strbuf_addstr(data->out, hex);
 257                 strbuf_addch(data->out, '\n');
 258         }
 259         return 0;
 260 }
 261
 262 static int write_shallow_commits_1(struct strbuf *out, int use_pack_protocol,
 263                                    const struct oid_array *extra,
 264                                    unsigned flags)
 265 {
 266         struct write_shallow_data data;
 267         int i;
 268         data.out = out;
 269         data.use_pack_protocol = use_pack_protocol;
 270         data.count = 0;
 271         data.flags = flags;
 272         for_each_commit_graft(write_one_shallow, &data);
 273         if (!extra)
 274                 return data.count;
 275         for (i = 0; i < extra->nr; i++) {
 276                 strbuf_addstr(out, oid_to_hex(extra->oid + i));
 277                 strbuf_addch(out, '\n');
 278                 data.count++;
 279         }
 280         return data.count;
 281 }
 282
 283 int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
 284                           const struct oid_array *extra)
 285 {
 286         return write_shallow_commits_1(out, use_pack_protocol, extra, 0);
 287 }
 288
 289 const char *setup_temporary_shallow(const struct oid_array *extra)
 290 {
 291         struct tempfile *temp;
 292         struct strbuf sb = STRBUF_INIT;
 293
 294         if (write_shallow_commits(&sb, 0, extra)) {
 295                 temp = xmks_tempfile(git_path("shallow_XXXXXX"));
 296
 297                 if (write_in_full(temp->fd, sb.buf, sb.len) < 0 ||
 298                     close_tempfile_gently(temp) < 0)
 299                         die_errno("failed to write to %s",
 300                                   get_tempfile_path(temp));
 301                 strbuf_release(&sb);
 302                 return get_tempfile_path(temp);
 303         }
 304         /*
 305          * is_repository_shallow() sees empty string as "no shallow
 306          * file".
 307          */
 308         return "";
 309 }
 310
 311 void setup_alternate_shallow(struct lock_file *shallow_lock,
 312                              const char **alternate_shallow_file,
 313                              const struct oid_array *extra)
 314 {
 315         struct strbuf sb = STRBUF_INIT;
 316         int fd;
 317
 318         fd = hold_lock_file_for_update(shallow_lock, git_path_shallow(),
 319                                        LOCK_DIE_ON_ERROR);
 320         check_shallow_file_for_update();
 321         if (write_shallow_commits(&sb, 0, extra)) {
 322                 if (write_in_full(fd, sb.buf, sb.len) < 0)
 323                         die_errno("failed to write to %s",
 324                                   get_lock_file_path(shallow_lock));
 325                 *alternate_shallow_file = get_lock_file_path(shallow_lock);
 326         } else
 327                 /*
 328                  * is_repository_shallow() sees empty string as "no
 329                  * shallow file".
 330                  */
 331                 *alternate_shallow_file = "";
 332         strbuf_release(&sb);
 333 }
 334
 335 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 336 {
 337         int fd = *(int *)cb;
 338         if (graft->nr_parent == -1)
 339                 packet_write_fmt(fd, "shallow %s\n", oid_to_hex(&graft->oid));
 340         return 0;
 341 }
 342
 343 void advertise_shallow_grafts(int fd)
 344 {
 345         if (!is_repository_shallow())
 346                 return;
 347         for_each_commit_graft(advertise_shallow_grafts_cb, &fd);
 348 }
 349
 350 /*
 351  * mark_reachable_objects() should have been run prior to this and all
 352  * reachable commits marked as "SEEN".
 353  */
 354 void prune_shallow(int show_only)
 355 {
 356         static struct lock_file shallow_lock;
 357         struct strbuf sb = STRBUF_INIT;
 358         int fd;
 359
 360         if (show_only) {
 361                 write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY | VERBOSE);
 362                 strbuf_release(&sb);
 363                 return;
 364         }
 365         fd = hold_lock_file_for_update(&shallow_lock, git_path_shallow(),
 366                                        LOCK_DIE_ON_ERROR);
 367         check_shallow_file_for_update();
 368         if (write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY)) {
 369                 if (write_in_full(fd, sb.buf, sb.len) < 0)
 370                         die_errno("failed to write to %s",
 371                                   get_lock_file_path(&shallow_lock));
 372                 commit_lock_file(&shallow_lock);
 373         } else {
 374                 unlink(git_path_shallow());
 375                 rollback_lock_file(&shallow_lock);
 376         }
 377         strbuf_release(&sb);
 378 }
 379
 380 struct trace_key trace_shallow = TRACE_KEY_INIT(SHALLOW);
 381
 382 /*
 383  * Step 1, split sender shallow commits into "ours" and "theirs"
 384  * Step 2, clean "ours" based on .git/shallow
 385  */
 386 void prepare_shallow_info(struct shallow_info *info, struct oid_array *sa)
 387 {
 388         int i;
 389         trace_printf_key(&trace_shallow, "shallow: prepare_shallow_info\n");
 390         memset(info, 0, sizeof(*info));
 391         info->shallow = sa;
 392         if (!sa)
 393                 return;
 394         ALLOC_ARRAY(info->ours, sa->nr);
 395         ALLOC_ARRAY(info->theirs, sa->nr);
 396         for (i = 0; i < sa->nr; i++) {
 397                 if (has_object_file(sa->oid + i)) {
 398                         struct commit_graft *graft;
 399                         graft = lookup_commit_graft(&sa->oid[i]);
 400                         if (graft && graft->nr_parent < 0)
 401                                 continue;
 402                         info->ours[info->nr_ours++] = i;
 403                 } else
 404                         info->theirs[info->nr_theirs++] = i;
 405         }
 406 }
 407
 408 void clear_shallow_info(struct shallow_info *info)
 409 {
 410         free(info->ours);
 411         free(info->theirs);
 412 }
 413
 414 /* Step 4, remove non-existent ones in "theirs" after getting the pack */
 415
 416 void remove_nonexistent_theirs_shallow(struct shallow_info *info)
 417 {
 418         struct object_id *oid = info->shallow->oid;
 419         int i, dst;
 420         trace_printf_key(&trace_shallow, "shallow: remove_nonexistent_theirs_shallow\n");
 421         for (i = dst = 0; i < info->nr_theirs; i++) {
 422                 if (i != dst)
 423                         info->theirs[dst] = info->theirs[i];
 424                 if (has_object_file(oid + info->theirs[i]))
 425                         dst++;
 426         }
 427         info->nr_theirs = dst;
 428 }
 429
 430 define_commit_slab(ref_bitmap, uint32_t *);
 431
 432 #define POOL_SIZE (512 * 1024)
 433
 434 struct paint_info {
 435         struct ref_bitmap ref_bitmap;
 436         unsigned nr_bits;
 437         char **pools;
 438         char *free, *end;
 439         unsigned pool_count;
 440 };
 441
 442 static uint32_t *paint_alloc(struct paint_info *info)
 443 {
 444         unsigned nr = DIV_ROUND_UP(info->nr_bits, 32);
 445         unsigned size = nr * sizeof(uint32_t);
 446         void *p;
 447         if (!info->pool_count || size > info->end - info->free) {
 448                 if (size > POOL_SIZE)
 449                         die("BUG: pool size too small for %d in paint_alloc()",
 450                             size);
 451                 info->pool_count++;
 452                 REALLOC_ARRAY(info->pools, info->pool_count);
 453                 info->free = xmalloc(POOL_SIZE);
 454                 info->pools[info->pool_count - 1] = info->free;
 455                 info->end = info->free + POOL_SIZE;
 456         }
 457         p = info->free;
 458         info->free += size;
 459         return p;
 460 }
 461
 462 /*
 463  * Given a commit SHA-1, walk down to parents until either SEEN,
 464  * UNINTERESTING or BOTTOM is hit. Set the id-th bit in ref_bitmap for
 465  * all walked commits.
 466  */
 467 static void paint_down(struct paint_info *info, const struct object_id *oid,
 468                        unsigned int id)
 469 {
 470         unsigned int i, nr;
 471         struct commit_list *head = NULL;
 472         int bitmap_nr = DIV_ROUND_UP(info->nr_bits, 32);
 473         size_t bitmap_size = st_mult(sizeof(uint32_t), bitmap_nr);
 474         struct commit *c = lookup_commit_reference_gently(oid, 1);
 475         uint32_t *tmp; /* to be freed before return */
 476         uint32_t *bitmap;
 477
 478         if (!c)
 479                 return;
 480
 481         tmp = xmalloc(bitmap_size);
 482         bitmap = paint_alloc(info);
 483         memset(bitmap, 0, bitmap_size);
 484         bitmap[id / 32] |= (1U << (id % 32));
 485         commit_list_insert(c, &head);
 486         while (head) {
 487                 struct commit_list *p;
 488                 struct commit *c = pop_commit(&head);
 489                 uint32_t **refs = ref_bitmap_at(&info->ref_bitmap, c);
 490
 491                 /* XXX check "UNINTERESTING" from pack bitmaps if available */
 492                 if (c->object.flags & (SEEN | UNINTERESTING))
 493                         continue;
 494                 else
 495                         c->object.flags |= SEEN;
 496
 497                 if (*refs == NULL)
 498                         *refs = bitmap;
 499                 else {
 500                         memcpy(tmp, *refs, bitmap_size);
 501                         for (i = 0; i < bitmap_nr; i++)
 502                                 tmp[i] |= bitmap[i];
 503                         if (memcmp(tmp, *refs, bitmap_size)) {
 504                                 *refs = paint_alloc(info);
 505                                 memcpy(*refs, tmp, bitmap_size);
 506                         }
 507                 }
 508
 509                 if (c->object.flags & BOTTOM)
 510                         continue;
 511
 512                 if (parse_commit(c))
 513                         die("unable to parse commit %s",
 514                             oid_to_hex(&c->object.oid));
 515
 516                 for (p = c->parents; p; p = p->next) {
 517                         if (p->item->object.flags & SEEN)
 518                                 continue;
 519                         commit_list_insert(p->item, &head);
 520                 }
 521         }
 522
 523         nr = get_max_object_index();
 524         for (i = 0; i < nr; i++) {
 525                 struct object *o = get_indexed_object(i);
 526                 if (o && o->type == OBJ_COMMIT)
 527                         o->flags &= ~SEEN;
 528         }
 529
 530         free(tmp);
 531 }
 532
 533 static int mark_uninteresting(const char *refname, const struct object_id *oid,
 534                               int flags, void *cb_data)
 535 {
 536         struct commit *commit = lookup_commit_reference_gently(oid, 1);
 537         if (!commit)
 538                 return 0;
 539         commit->object.flags |= UNINTERESTING;
 540         mark_parents_uninteresting(commit);
 541         return 0;
 542 }
 543
 544 static void post_assign_shallow(struct shallow_info *info,
 545                                 struct ref_bitmap *ref_bitmap,
 546                                 int *ref_status);
 547 /*
 548  * Step 6(+7), associate shallow commits with new refs
 549  *
 550  * info->ref must be initialized before calling this function.
 551  *
 552  * If used is not NULL, it's an array of info->shallow->nr
 553  * bitmaps. The n-th bit set in the m-th bitmap if ref[n] needs the
 554  * m-th shallow commit from info->shallow.
 555  *
 556  * If used is NULL, "ours" and "theirs" are updated. And if ref_status
 557  * is not NULL it's an array of ref->nr ints. ref_status[i] is true if
 558  * the ref needs some shallow commits from either info->ours or
 559  * info->theirs.
 560  */
 561 void assign_shallow_commits_to_refs(struct shallow_info *info,
 562                                     uint32_t **used, int *ref_status)
 563 {
 564         struct object_id *oid = info->shallow->oid;
 565         struct oid_array *ref = info->ref;
 566         unsigned int i, nr;
 567         int *shallow, nr_shallow = 0;
 568         struct paint_info pi;
 569
 570         trace_printf_key(&trace_shallow, "shallow: assign_shallow_commits_to_refs\n");
 571         ALLOC_ARRAY(shallow, info->nr_ours + info->nr_theirs);
 572         for (i = 0; i < info->nr_ours; i++)
 573                 shallow[nr_shallow++] = info->ours[i];
 574         for (i = 0; i < info->nr_theirs; i++)
 575                 shallow[nr_shallow++] = info->theirs[i];
 576
 577         /*
 578          * Prepare the commit graph to track what refs can reach what
 579          * (new) shallow commits.
 580          */
 581         nr = get_max_object_index();
 582         for (i = 0; i < nr; i++) {
 583                 struct object *o = get_indexed_object(i);
 584                 if (!o || o->type != OBJ_COMMIT)
 585                         continue;
 586
 587                 o->flags &= ~(UNINTERESTING | BOTTOM | SEEN);
 588         }
 589
 590         memset(&pi, 0, sizeof(pi));
 591         init_ref_bitmap(&pi.ref_bitmap);
 592         pi.nr_bits = ref->nr;
 593
 594         /*
 595          * "--not --all" to cut short the traversal if new refs
 596          * connect to old refs. If not (e.g. force ref updates) it'll
 597          * have to go down to the current shallow commits.
 598          */
 599         head_ref(mark_uninteresting, NULL);
 600         for_each_ref(mark_uninteresting, NULL);
 601
 602         /* Mark potential bottoms so we won't go out of bound */
 603         for (i = 0; i < nr_shallow; i++) {
 604                 struct commit *c = lookup_commit(&oid[shallow[i]]);
 605                 c->object.flags |= BOTTOM;
 606         }
 607
 608         for (i = 0; i < ref->nr; i++)
 609                 paint_down(&pi, ref->oid + i, i);
 610
 611         if (used) {
 612                 int bitmap_size = DIV_ROUND_UP(pi.nr_bits, 32) * sizeof(uint32_t);
 613                 memset(used, 0, sizeof(*used) * info->shallow->nr);
 614                 for (i = 0; i < nr_shallow; i++) {
 615                         const struct commit *c = lookup_commit(&oid[shallow[i]]);
 616                         uint32_t **map = ref_bitmap_at(&pi.ref_bitmap, c);
 617                         if (*map)
 618                                 used[shallow[i]] = xmemdupz(*map, bitmap_size);
 619                 }
 620                 /*
 621                  * unreachable shallow commits are not removed from
 622                  * "ours" and "theirs". The user is supposed to run
 623                  * step 7 on every ref separately and not trust "ours"
 624                  * and "theirs" any more.
 625                  */
 626         } else
 627                 post_assign_shallow(info, &pi.ref_bitmap, ref_status);
 628
 629         clear_ref_bitmap(&pi.ref_bitmap);
 630         for (i = 0; i < pi.pool_count; i++)
 631                 free(pi.pools[i]);
 632         free(pi.pools);
 633         free(shallow);
 634 }
 635
 636 struct commit_array {
 637         struct commit **commits;
 638         int nr, alloc;
 639 };
 640
 641 static int add_ref(const char *refname, const struct object_id *oid,
 642                    int flags, void *cb_data)
 643 {
 644         struct commit_array *ca = cb_data;
 645         ALLOC_GROW(ca->commits, ca->nr + 1, ca->alloc);
 646         ca->commits[ca->nr] = lookup_commit_reference_gently(oid, 1);
 647         if (ca->commits[ca->nr])
 648                 ca->nr++;
 649         return 0;
 650 }
 651
 652 static void update_refstatus(int *ref_status, int nr, uint32_t *bitmap)
 653 {
 654         unsigned int i;
 655         if (!ref_status)
 656                 return;
 657         for (i = 0; i < nr; i++)
 658                 if (bitmap[i / 32] & (1U << (i % 32)))
 659                         ref_status[i]++;
 660 }
 661
 662 /*
 663  * Step 7, reachability test on "ours" at commit level
 664  */
 665 static void post_assign_shallow(struct shallow_info *info,
 666                                 struct ref_bitmap *ref_bitmap,
 667                                 int *ref_status)
 668 {
 669         struct object_id *oid = info->shallow->oid;
 670         struct commit *c;
 671         uint32_t **bitmap;
 672         int dst, i, j;
 673         int bitmap_nr = DIV_ROUND_UP(info->ref->nr, 32);
 674         struct commit_array ca;
 675
 676         trace_printf_key(&trace_shallow, "shallow: post_assign_shallow\n");
 677         if (ref_status)
 678                 memset(ref_status, 0, sizeof(*ref_status) * info->ref->nr);
 679
 680         /* Remove unreachable shallow commits from "theirs" */
 681         for (i = dst = 0; i < info->nr_theirs; i++) {
 682                 if (i != dst)
 683                         info->theirs[dst] = info->theirs[i];
 684                 c = lookup_commit(&oid[info->theirs[i]]);
 685                 bitmap = ref_bitmap_at(ref_bitmap, c);
 686                 if (!*bitmap)
 687                         continue;
 688                 for (j = 0; j < bitmap_nr; j++)
 689                         if (bitmap[0][j]) {
 690                                 update_refstatus(ref_status, info->ref->nr, *bitmap);
 691                                 dst++;
 692                                 break;
 693                         }
 694         }
 695         info->nr_theirs = dst;
 696
 697         memset(&ca, 0, sizeof(ca));
 698         head_ref(add_ref, &ca);
 699         for_each_ref(add_ref, &ca);
 700
 701         /* Remove unreachable shallow commits from "ours" */
 702         for (i = dst = 0; i < info->nr_ours; i++) {
 703                 if (i != dst)
 704                         info->ours[dst] = info->ours[i];
 705                 c = lookup_commit(&oid[info->ours[i]]);
 706                 bitmap = ref_bitmap_at(ref_bitmap, c);
 707                 if (!*bitmap)
 708                         continue;
 709                 for (j = 0; j < bitmap_nr; j++)
 710                         if (bitmap[0][j] &&
 711                             /* Step 7, reachability test at commit level */
 712                             !in_merge_bases_many(c, ca.nr, ca.commits)) {
 713                                 update_refstatus(ref_status, info->ref->nr, *bitmap);
 714                                 dst++;
 715                                 break;
 716                         }
 717         }
 718         info->nr_ours = dst;
 719
 720         free(ca.commits);
 721 }
 722
 723 /* (Delayed) step 7, reachability test at commit level */
 724 int delayed_reachability_test(struct shallow_info *si, int c)
 725 {
 726         if (si->need_reachability_test[c]) {
 727                 struct commit *commit = lookup_commit(&si->shallow->oid[c]);
 728
 729                 if (!si->commits) {
 730                         struct commit_array ca;
 731
 732                         memset(&ca, 0, sizeof(ca));
 733                         head_ref(add_ref, &ca);
 734                         for_each_ref(add_ref, &ca);
 735                         si->commits = ca.commits;
 736                         si->nr_commits = ca.nr;
 737                 }
 738
 739                 si->reachable[c] = in_merge_bases_many(commit,
 740                                                        si->nr_commits,
 741                                                        si->commits);
 742                 si->need_reachability_test[c] = 0;
 743         }
 744         return si->reachable[c];
 745 }