shallow.con commit Merge branch 'jk/config-die-bad-number-noreturn' (531675a)
   1#include "cache.h"
   2#include "commit.h"
   3#include "tag.h"
   4#include "pkt-line.h"
   5#include "remote.h"
   6#include "refs.h"
   7#include "sha1-array.h"
   8#include "diff.h"
   9#include "revision.h"
  10#include "commit-slab.h"
  11#include "sigchain.h"
  12
  13static int is_shallow = -1;
  14static struct stat_validity shallow_stat;
  15static char *alternate_shallow_file;
  16
  17void set_alternate_shallow_file(const char *path, int override)
  18{
  19        if (is_shallow != -1)
  20                die("BUG: is_repository_shallow must not be called before set_alternate_shallow_file");
  21        if (alternate_shallow_file && !override)
  22                return;
  23        free(alternate_shallow_file);
  24        alternate_shallow_file = path ? xstrdup(path) : NULL;
  25}
  26
  27int register_shallow(const unsigned char *sha1)
  28{
  29        struct commit_graft *graft =
  30                xmalloc(sizeof(struct commit_graft));
  31        struct commit *commit = lookup_commit(sha1);
  32
  33        hashcpy(graft->sha1, sha1);
  34        graft->nr_parent = -1;
  35        if (commit && commit->object.parsed)
  36                commit->parents = NULL;
  37        return register_commit_graft(graft, 0);
  38}
  39
  40int is_repository_shallow(void)
  41{
  42        FILE *fp;
  43        char buf[1024];
  44        const char *path = alternate_shallow_file;
  45
  46        if (is_shallow >= 0)
  47                return is_shallow;
  48
  49        if (!path)
  50                path = git_path("shallow");
  51        /*
  52         * fetch-pack sets '--shallow-file ""' as an indicator that no
  53         * shallow file should be used. We could just open it and it
  54         * will likely fail. But let's do an explicit check instead.
  55         */
  56        if (!*path || (fp = fopen(path, "r")) == NULL) {
  57                stat_validity_clear(&shallow_stat);
  58                is_shallow = 0;
  59                return is_shallow;
  60        }
  61        stat_validity_update(&shallow_stat, fileno(fp));
  62        is_shallow = 1;
  63
  64        while (fgets(buf, sizeof(buf), fp)) {
  65                unsigned char sha1[20];
  66                if (get_sha1_hex(buf, sha1))
  67                        die("bad shallow line: %s", buf);
  68                register_shallow(sha1);
  69        }
  70        fclose(fp);
  71        return is_shallow;
  72}
  73
  74struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
  75                int shallow_flag, int not_shallow_flag)
  76{
  77        int i = 0, cur_depth = 0;
  78        struct commit_list *result = NULL;
  79        struct object_array stack = OBJECT_ARRAY_INIT;
  80        struct commit *commit = NULL;
  81        struct commit_graft *graft;
  82
  83        while (commit || i < heads->nr || stack.nr) {
  84                struct commit_list *p;
  85                if (!commit) {
  86                        if (i < heads->nr) {
  87                                commit = (struct commit *)
  88                                        deref_tag(heads->objects[i++].item, NULL, 0);
  89                                if (!commit || commit->object.type != OBJ_COMMIT) {
  90                                        commit = NULL;
  91                                        continue;
  92                                }
  93                                if (!commit->util)
  94                                        commit->util = xmalloc(sizeof(int));
  95                                *(int *)commit->util = 0;
  96                                cur_depth = 0;
  97                        } else {
  98                                commit = (struct commit *)
  99                                        stack.objects[--stack.nr].item;
 100                                cur_depth = *(int *)commit->util;
 101                        }
 102                }
 103                parse_commit_or_die(commit);
 104                cur_depth++;
 105                if ((depth != INFINITE_DEPTH && cur_depth >= depth) ||
 106                    (is_repository_shallow() && !commit->parents &&
 107                     (graft = lookup_commit_graft(commit->object.sha1)) != NULL &&
 108                     graft->nr_parent < 0)) {
 109                        commit_list_insert(commit, &result);
 110                        commit->object.flags |= shallow_flag;
 111                        commit = NULL;
 112                        continue;
 113                }
 114                commit->object.flags |= not_shallow_flag;
 115                for (p = commit->parents, commit = NULL; p; p = p->next) {
 116                        if (!p->item->util) {
 117                                int *pointer = xmalloc(sizeof(int));
 118                                p->item->util = pointer;
 119                                *pointer =  cur_depth;
 120                        } else {
 121                                int *pointer = p->item->util;
 122                                if (cur_depth >= *pointer)
 123                                        continue;
 124                                *pointer = cur_depth;
 125                        }
 126                        if (p->next)
 127                                add_object_array(&p->item->object,
 128                                                NULL, &stack);
 129                        else {
 130                                commit = p->item;
 131                                cur_depth = *(int *)commit->util;
 132                        }
 133                }
 134        }
 135
 136        return result;
 137}
 138
 139void check_shallow_file_for_update(void)
 140{
 141        if (is_shallow == -1)
 142                die("BUG: shallow must be initialized by now");
 143
 144        if (!stat_validity_check(&shallow_stat, git_path("shallow")))
 145                die("shallow file has changed since we read it");
 146}
 147
 148#define SEEN_ONLY 1
 149#define VERBOSE   2
 150
 151struct write_shallow_data {
 152        struct strbuf *out;
 153        int use_pack_protocol;
 154        int count;
 155        unsigned flags;
 156};
 157
 158static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
 159{
 160        struct write_shallow_data *data = cb_data;
 161        const char *hex = sha1_to_hex(graft->sha1);
 162        if (graft->nr_parent != -1)
 163                return 0;
 164        if (data->flags & SEEN_ONLY) {
 165                struct commit *c = lookup_commit(graft->sha1);
 166                if (!c || !(c->object.flags & SEEN)) {
 167                        if (data->flags & VERBOSE)
 168                                printf("Removing %s from .git/shallow\n",
 169                                       sha1_to_hex(c->object.sha1));
 170                        return 0;
 171                }
 172        }
 173        data->count++;
 174        if (data->use_pack_protocol)
 175                packet_buf_write(data->out, "shallow %s", hex);
 176        else {
 177                strbuf_addstr(data->out, hex);
 178                strbuf_addch(data->out, '\n');
 179        }
 180        return 0;
 181}
 182
 183static int write_shallow_commits_1(struct strbuf *out, int use_pack_protocol,
 184                                   const struct sha1_array *extra,
 185                                   unsigned flags)
 186{
 187        struct write_shallow_data data;
 188        int i;
 189        data.out = out;
 190        data.use_pack_protocol = use_pack_protocol;
 191        data.count = 0;
 192        data.flags = flags;
 193        for_each_commit_graft(write_one_shallow, &data);
 194        if (!extra)
 195                return data.count;
 196        for (i = 0; i < extra->nr; i++) {
 197                strbuf_addstr(out, sha1_to_hex(extra->sha1[i]));
 198                strbuf_addch(out, '\n');
 199                data.count++;
 200        }
 201        return data.count;
 202}
 203
 204int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
 205                          const struct sha1_array *extra)
 206{
 207        return write_shallow_commits_1(out, use_pack_protocol, extra, 0);
 208}
 209
 210static struct strbuf temporary_shallow = STRBUF_INIT;
 211
 212static void remove_temporary_shallow(void)
 213{
 214        if (temporary_shallow.len) {
 215                unlink_or_warn(temporary_shallow.buf);
 216                strbuf_reset(&temporary_shallow);
 217        }
 218}
 219
 220static void remove_temporary_shallow_on_signal(int signo)
 221{
 222        remove_temporary_shallow();
 223        sigchain_pop(signo);
 224        raise(signo);
 225}
 226
 227const char *setup_temporary_shallow(const struct sha1_array *extra)
 228{
 229        static int installed_handler;
 230        struct strbuf sb = STRBUF_INIT;
 231        int fd;
 232
 233        if (temporary_shallow.len)
 234                die("BUG: attempt to create two temporary shallow files");
 235
 236        if (write_shallow_commits(&sb, 0, extra)) {
 237                strbuf_addstr(&temporary_shallow, git_path("shallow_XXXXXX"));
 238                fd = xmkstemp(temporary_shallow.buf);
 239
 240                if (!installed_handler) {
 241                        atexit(remove_temporary_shallow);
 242                        sigchain_push_common(remove_temporary_shallow_on_signal);
 243                }
 244
 245                if (write_in_full(fd, sb.buf, sb.len) != sb.len)
 246                        die_errno("failed to write to %s",
 247                                  temporary_shallow.buf);
 248                close(fd);
 249                strbuf_release(&sb);
 250                return temporary_shallow.buf;
 251        }
 252        /*
 253         * is_repository_shallow() sees empty string as "no shallow
 254         * file".
 255         */
 256        return temporary_shallow.buf;
 257}
 258
 259void setup_alternate_shallow(struct lock_file *shallow_lock,
 260                             const char **alternate_shallow_file,
 261                             const struct sha1_array *extra)
 262{
 263        struct strbuf sb = STRBUF_INIT;
 264        int fd;
 265
 266        fd = hold_lock_file_for_update(shallow_lock, git_path("shallow"),
 267                                       LOCK_DIE_ON_ERROR);
 268        check_shallow_file_for_update();
 269        if (write_shallow_commits(&sb, 0, extra)) {
 270                if (write_in_full(fd, sb.buf, sb.len) != sb.len)
 271                        die_errno("failed to write to %s",
 272                                  shallow_lock->filename);
 273                *alternate_shallow_file = shallow_lock->filename;
 274        } else
 275                /*
 276                 * is_repository_shallow() sees empty string as "no
 277                 * shallow file".
 278                 */
 279                *alternate_shallow_file = "";
 280        strbuf_release(&sb);
 281}
 282
 283static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 284{
 285        int fd = *(int *)cb;
 286        if (graft->nr_parent == -1)
 287                packet_write(fd, "shallow %s\n", sha1_to_hex(graft->sha1));
 288        return 0;
 289}
 290
 291void advertise_shallow_grafts(int fd)
 292{
 293        if (!is_repository_shallow())
 294                return;
 295        for_each_commit_graft(advertise_shallow_grafts_cb, &fd);
 296}
 297
 298/*
 299 * mark_reachable_objects() should have been run prior to this and all
 300 * reachable commits marked as "SEEN".
 301 */
 302void prune_shallow(int show_only)
 303{
 304        static struct lock_file shallow_lock;
 305        struct strbuf sb = STRBUF_INIT;
 306        int fd;
 307
 308        if (show_only) {
 309                write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY | VERBOSE);
 310                strbuf_release(&sb);
 311                return;
 312        }
 313        fd = hold_lock_file_for_update(&shallow_lock, git_path("shallow"),
 314                                       LOCK_DIE_ON_ERROR);
 315        check_shallow_file_for_update();
 316        if (write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY)) {
 317                if (write_in_full(fd, sb.buf, sb.len) != sb.len)
 318                        die_errno("failed to write to %s",
 319                                  shallow_lock.filename);
 320                commit_lock_file(&shallow_lock);
 321        } else {
 322                unlink(git_path("shallow"));
 323                rollback_lock_file(&shallow_lock);
 324        }
 325        strbuf_release(&sb);
 326}
 327
 328#define TRACE_KEY "GIT_TRACE_SHALLOW"
 329
 330/*
 331 * Step 1, split sender shallow commits into "ours" and "theirs"
 332 * Step 2, clean "ours" based on .git/shallow
 333 */
 334void prepare_shallow_info(struct shallow_info *info, struct sha1_array *sa)
 335{
 336        int i;
 337        trace_printf_key(TRACE_KEY, "shallow: prepare_shallow_info\n");
 338        memset(info, 0, sizeof(*info));
 339        info->shallow = sa;
 340        if (!sa)
 341                return;
 342        info->ours = xmalloc(sizeof(*info->ours) * sa->nr);
 343        info->theirs = xmalloc(sizeof(*info->theirs) * sa->nr);
 344        for (i = 0; i < sa->nr; i++) {
 345                if (has_sha1_file(sa->sha1[i])) {
 346                        struct commit_graft *graft;
 347                        graft = lookup_commit_graft(sa->sha1[i]);
 348                        if (graft && graft->nr_parent < 0)
 349                                continue;
 350                        info->ours[info->nr_ours++] = i;
 351                } else
 352                        info->theirs[info->nr_theirs++] = i;
 353        }
 354}
 355
 356void clear_shallow_info(struct shallow_info *info)
 357{
 358        free(info->ours);
 359        free(info->theirs);
 360}
 361
 362/* Step 4, remove non-existent ones in "theirs" after getting the pack */
 363
 364void remove_nonexistent_theirs_shallow(struct shallow_info *info)
 365{
 366        unsigned char (*sha1)[20] = info->shallow->sha1;
 367        int i, dst;
 368        trace_printf_key(TRACE_KEY, "shallow: remove_nonexistent_theirs_shallow\n");
 369        for (i = dst = 0; i < info->nr_theirs; i++) {
 370                if (i != dst)
 371                        info->theirs[dst] = info->theirs[i];
 372                if (has_sha1_file(sha1[info->theirs[i]]))
 373                        dst++;
 374        }
 375        info->nr_theirs = dst;
 376}
 377
 378define_commit_slab(ref_bitmap, uint32_t *);
 379
 380struct paint_info {
 381        struct ref_bitmap ref_bitmap;
 382        unsigned nr_bits;
 383        char **slab;
 384        char *free, *end;
 385        unsigned slab_count;
 386};
 387
 388static uint32_t *paint_alloc(struct paint_info *info)
 389{
 390        unsigned nr = (info->nr_bits + 31) / 32;
 391        unsigned size = nr * sizeof(uint32_t);
 392        void *p;
 393        if (!info->slab_count || info->free + size > info->end) {
 394                info->slab_count++;
 395                info->slab = xrealloc(info->slab,
 396                                      info->slab_count * sizeof(*info->slab));
 397                info->free = xmalloc(COMMIT_SLAB_SIZE);
 398                info->slab[info->slab_count - 1] = info->free;
 399                info->end = info->free + COMMIT_SLAB_SIZE;
 400        }
 401        p = info->free;
 402        info->free += size;
 403        return p;
 404}
 405
 406/*
 407 * Given a commit SHA-1, walk down to parents until either SEEN,
 408 * UNINTERESTING or BOTTOM is hit. Set the id-th bit in ref_bitmap for
 409 * all walked commits.
 410 */
 411static void paint_down(struct paint_info *info, const unsigned char *sha1,
 412                       int id)
 413{
 414        unsigned int i, nr;
 415        struct commit_list *head = NULL;
 416        int bitmap_nr = (info->nr_bits + 31) / 32;
 417        int bitmap_size = bitmap_nr * sizeof(uint32_t);
 418        uint32_t *tmp = xmalloc(bitmap_size); /* to be freed before return */
 419        uint32_t *bitmap = paint_alloc(info);
 420        struct commit *c = lookup_commit_reference_gently(sha1, 1);
 421        if (!c)
 422                return;
 423        memset(bitmap, 0, bitmap_size);
 424        bitmap[id / 32] |= (1 << (id % 32));
 425        commit_list_insert(c, &head);
 426        while (head) {
 427                struct commit_list *p;
 428                struct commit *c = head->item;
 429                uint32_t **refs = ref_bitmap_at(&info->ref_bitmap, c);
 430
 431                p = head;
 432                head = head->next;
 433                free(p);
 434
 435                /* XXX check "UNINTERESTING" from pack bitmaps if available */
 436                if (c->object.flags & (SEEN | UNINTERESTING))
 437                        continue;
 438                else
 439                        c->object.flags |= SEEN;
 440
 441                if (*refs == NULL)
 442                        *refs = bitmap;
 443                else {
 444                        memcpy(tmp, *refs, bitmap_size);
 445                        for (i = 0; i < bitmap_nr; i++)
 446                                tmp[i] |= bitmap[i];
 447                        if (memcmp(tmp, *refs, bitmap_size)) {
 448                                *refs = paint_alloc(info);
 449                                memcpy(*refs, tmp, bitmap_size);
 450                        }
 451                }
 452
 453                if (c->object.flags & BOTTOM)
 454                        continue;
 455
 456                if (parse_commit(c))
 457                        die("unable to parse commit %s",
 458                            sha1_to_hex(c->object.sha1));
 459
 460                for (p = c->parents; p; p = p->next) {
 461                        uint32_t **p_refs = ref_bitmap_at(&info->ref_bitmap,
 462                                                          p->item);
 463                        if (p->item->object.flags & SEEN)
 464                                continue;
 465                        if (*p_refs == NULL || *p_refs == *refs)
 466                                *p_refs = *refs;
 467                        commit_list_insert(p->item, &head);
 468                }
 469        }
 470
 471        nr = get_max_object_index();
 472        for (i = 0; i < nr; i++) {
 473                struct object *o = get_indexed_object(i);
 474                if (o && o->type == OBJ_COMMIT)
 475                        o->flags &= ~SEEN;
 476        }
 477
 478        free(tmp);
 479}
 480
 481static int mark_uninteresting(const char *refname,
 482                              const unsigned char *sha1,
 483                              int flags, void *cb_data)
 484{
 485        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 486        if (!commit)
 487                return 0;
 488        commit->object.flags |= UNINTERESTING;
 489        mark_parents_uninteresting(commit);
 490        return 0;
 491}
 492
 493static void post_assign_shallow(struct shallow_info *info,
 494                                struct ref_bitmap *ref_bitmap,
 495                                int *ref_status);
 496/*
 497 * Step 6(+7), associate shallow commits with new refs
 498 *
 499 * info->ref must be initialized before calling this function.
 500 *
 501 * If used is not NULL, it's an array of info->shallow->nr
 502 * bitmaps. The n-th bit set in the m-th bitmap if ref[n] needs the
 503 * m-th shallow commit from info->shallow.
 504 *
 505 * If used is NULL, "ours" and "theirs" are updated. And if ref_status
 506 * is not NULL it's an array of ref->nr ints. ref_status[i] is true if
 507 * the ref needs some shallow commits from either info->ours or
 508 * info->theirs.
 509 */
 510void assign_shallow_commits_to_refs(struct shallow_info *info,
 511                                    uint32_t **used, int *ref_status)
 512{
 513        unsigned char (*sha1)[20] = info->shallow->sha1;
 514        struct sha1_array *ref = info->ref;
 515        unsigned int i, nr;
 516        int *shallow, nr_shallow = 0;
 517        struct paint_info pi;
 518
 519        trace_printf_key(TRACE_KEY, "shallow: assign_shallow_commits_to_refs\n");
 520        shallow = xmalloc(sizeof(*shallow) * (info->nr_ours + info->nr_theirs));
 521        for (i = 0; i < info->nr_ours; i++)
 522                shallow[nr_shallow++] = info->ours[i];
 523        for (i = 0; i < info->nr_theirs; i++)
 524                shallow[nr_shallow++] = info->theirs[i];
 525
 526        /*
 527         * Prepare the commit graph to track what refs can reach what
 528         * (new) shallow commits.
 529         */
 530        nr = get_max_object_index();
 531        for (i = 0; i < nr; i++) {
 532                struct object *o = get_indexed_object(i);
 533                if (!o || o->type != OBJ_COMMIT)
 534                        continue;
 535
 536                o->flags &= ~(UNINTERESTING | BOTTOM | SEEN);
 537        }
 538
 539        memset(&pi, 0, sizeof(pi));
 540        init_ref_bitmap(&pi.ref_bitmap);
 541        pi.nr_bits = ref->nr;
 542
 543        /*
 544         * "--not --all" to cut short the traversal if new refs
 545         * connect to old refs. If not (e.g. force ref updates) it'll
 546         * have to go down to the current shallow commits.
 547         */
 548        head_ref(mark_uninteresting, NULL);
 549        for_each_ref(mark_uninteresting, NULL);
 550
 551        /* Mark potential bottoms so we won't go out of bound */
 552        for (i = 0; i < nr_shallow; i++) {
 553                struct commit *c = lookup_commit(sha1[shallow[i]]);
 554                c->object.flags |= BOTTOM;
 555        }
 556
 557        for (i = 0; i < ref->nr; i++)
 558                paint_down(&pi, ref->sha1[i], i);
 559
 560        if (used) {
 561                int bitmap_size = ((pi.nr_bits + 31) / 32) * sizeof(uint32_t);
 562                memset(used, 0, sizeof(*used) * info->shallow->nr);
 563                for (i = 0; i < nr_shallow; i++) {
 564                        const struct commit *c = lookup_commit(sha1[shallow[i]]);
 565                        uint32_t **map = ref_bitmap_at(&pi.ref_bitmap, c);
 566                        if (*map)
 567                                used[shallow[i]] = xmemdupz(*map, bitmap_size);
 568                }
 569                /*
 570                 * unreachable shallow commits are not removed from
 571                 * "ours" and "theirs". The user is supposed to run
 572                 * step 7 on every ref separately and not trust "ours"
 573                 * and "theirs" any more.
 574                 */
 575        } else
 576                post_assign_shallow(info, &pi.ref_bitmap, ref_status);
 577
 578        clear_ref_bitmap(&pi.ref_bitmap);
 579        for (i = 0; i < pi.slab_count; i++)
 580                free(pi.slab[i]);
 581        free(pi.slab);
 582        free(shallow);
 583}
 584
 585struct commit_array {
 586        struct commit **commits;
 587        int nr, alloc;
 588};
 589
 590static int add_ref(const char *refname,
 591                   const unsigned char *sha1, int flags, void *cb_data)
 592{
 593        struct commit_array *ca = cb_data;
 594        ALLOC_GROW(ca->commits, ca->nr + 1, ca->alloc);
 595        ca->commits[ca->nr] = lookup_commit_reference_gently(sha1, 1);
 596        if (ca->commits[ca->nr])
 597                ca->nr++;
 598        return 0;
 599}
 600
 601static void update_refstatus(int *ref_status, int nr, uint32_t *bitmap)
 602{
 603        int i;
 604        if (!ref_status)
 605                return;
 606        for (i = 0; i < nr; i++)
 607                if (bitmap[i / 32] & (1 << (i % 32)))
 608                        ref_status[i]++;
 609}
 610
 611/*
 612 * Step 7, reachability test on "ours" at commit level
 613 */
 614static void post_assign_shallow(struct shallow_info *info,
 615                                struct ref_bitmap *ref_bitmap,
 616                                int *ref_status)
 617{
 618        unsigned char (*sha1)[20] = info->shallow->sha1;
 619        struct commit *c;
 620        uint32_t **bitmap;
 621        int dst, i, j;
 622        int bitmap_nr = (info->ref->nr + 31) / 32;
 623        struct commit_array ca;
 624
 625        trace_printf_key(TRACE_KEY, "shallow: post_assign_shallow\n");
 626        if (ref_status)
 627                memset(ref_status, 0, sizeof(*ref_status) * info->ref->nr);
 628
 629        /* Remove unreachable shallow commits from "theirs" */
 630        for (i = dst = 0; i < info->nr_theirs; i++) {
 631                if (i != dst)
 632                        info->theirs[dst] = info->theirs[i];
 633                c = lookup_commit(sha1[info->theirs[i]]);
 634                bitmap = ref_bitmap_at(ref_bitmap, c);
 635                if (!*bitmap)
 636                        continue;
 637                for (j = 0; j < bitmap_nr; j++)
 638                        if (bitmap[0][j]) {
 639                                update_refstatus(ref_status, info->ref->nr, *bitmap);
 640                                dst++;
 641                                break;
 642                        }
 643        }
 644        info->nr_theirs = dst;
 645
 646        memset(&ca, 0, sizeof(ca));
 647        head_ref(add_ref, &ca);
 648        for_each_ref(add_ref, &ca);
 649
 650        /* Remove unreachable shallow commits from "ours" */
 651        for (i = dst = 0; i < info->nr_ours; i++) {
 652                if (i != dst)
 653                        info->ours[dst] = info->ours[i];
 654                c = lookup_commit(sha1[info->ours[i]]);
 655                bitmap = ref_bitmap_at(ref_bitmap, c);
 656                if (!*bitmap)
 657                        continue;
 658                for (j = 0; j < bitmap_nr; j++)
 659                        if (bitmap[0][j] &&
 660                            /* Step 7, reachability test at commit level */
 661                            !in_merge_bases_many(c, ca.nr, ca.commits)) {
 662                                update_refstatus(ref_status, info->ref->nr, *bitmap);
 663                                dst++;
 664                                break;
 665                        }
 666        }
 667        info->nr_ours = dst;
 668
 669        free(ca.commits);
 670}
 671
 672/* (Delayed) step 7, reachability test at commit level */
 673int delayed_reachability_test(struct shallow_info *si, int c)
 674{
 675        if (si->need_reachability_test[c]) {
 676                struct commit *commit = lookup_commit(si->shallow->sha1[c]);
 677
 678                if (!si->commits) {
 679                        struct commit_array ca;
 680                        memset(&ca, 0, sizeof(ca));
 681                        head_ref(add_ref, &ca);
 682                        for_each_ref(add_ref, &ca);
 683                        si->commits = ca.commits;
 684                        si->nr_commits = ca.nr;
 685                }
 686
 687                si->reachable[c] = in_merge_bases_many(commit,
 688                                                       si->nr_commits,
 689                                                       si->commits);
 690                si->need_reachability_test[c] = 0;
 691        }
 692        return si->reachable[c];
 693}