shallow.con commit Merge branch 'hn/string-list-doc' (d9ec072)
   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
  16static int is_shallow = -1;
  17static struct stat_validity shallow_stat;
  18static char *alternate_shallow_file;
  19
  20void 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
  30int 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
  43int 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
  77struct 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
 142static 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 */
 153struct 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
 218static 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
 230struct write_shallow_data {
 231        struct strbuf *out;
 232        int use_pack_protocol;
 233        int count;
 234        unsigned flags;
 235};
 236
 237static 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
 262static 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
 283int 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
 289const 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
 311void 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
 335static 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
 343void 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 */
 354void 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
 380struct 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 */
 386void 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
 408void 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
 416void 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
 430define_commit_slab(ref_bitmap, uint32_t *);
 431
 432#define POOL_SIZE (512 * 1024)
 433
 434struct 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
 442static 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 */
 467static 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
 533static 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
 544static 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 */
 561void 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
 636struct commit_array {
 637        struct commit **commits;
 638        int nr, alloc;
 639};
 640
 641static 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
 652static 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 */
 665static 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 */
 724int 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}