Andrew's git - gitweb.git/blob

   1#include "builtin.h"
   2#include "config.h"
   3#include "lockfile.h"
   4#include "object-store.h"
   5#include "repository.h"
   6#include "commit.h"
   7#include "refs.h"
   8#include "dir.h"
   9#include "tree-walk.h"
  10#include "diff.h"
  11#include "revision.h"
  12#include "reachable.h"
  13
  14/* NEEDSWORK: switch to using parse_options */
  15static const char reflog_expire_usage[] =
  16"git reflog expire [--expire=<time>] [--expire-unreachable=<time>] [--rewrite] [--updateref] [--stale-fix] [--dry-run | -n] [--verbose] [--all] <refs>...";
  17static const char reflog_delete_usage[] =
  18"git reflog delete [--rewrite] [--updateref] [--dry-run | -n] [--verbose] <refs>...";
  19static const char reflog_exists_usage[] =
  20"git reflog exists <ref>";
  21
  22static timestamp_t default_reflog_expire;
  23static timestamp_t default_reflog_expire_unreachable;
  24
  25struct cmd_reflog_expire_cb {
  26        struct rev_info revs;
  27        int stalefix;
  28        timestamp_t expire_total;
  29        timestamp_t expire_unreachable;
  30        int recno;
  31};
  32
  33struct expire_reflog_policy_cb {
  34        enum {
  35                UE_NORMAL,
  36                UE_ALWAYS,
  37                UE_HEAD
  38        } unreachable_expire_kind;
  39        struct commit_list *mark_list;
  40        unsigned long mark_limit;
  41        struct cmd_reflog_expire_cb cmd;
  42        struct commit *tip_commit;
  43        struct commit_list *tips;
  44};
  45
  46struct collected_reflog {
  47        struct object_id oid;
  48        char reflog[FLEX_ARRAY];
  49};
  50
  51struct collect_reflog_cb {
  52        struct collected_reflog **e;
  53        int alloc;
  54        int nr;
  55};
  56
  57/* Remember to update object flag allocation in object.h */
  58#define INCOMPLETE      (1u<<10)
  59#define STUDYING        (1u<<11)
  60#define REACHABLE       (1u<<12)
  61
  62static int tree_is_complete(const struct object_id *oid)
  63{
  64        struct tree_desc desc;
  65        struct name_entry entry;
  66        int complete;
  67        struct tree *tree;
  68
  69        tree = lookup_tree(the_repository, oid);
  70        if (!tree)
  71                return 0;
  72        if (tree->object.flags & SEEN)
  73                return 1;
  74        if (tree->object.flags & INCOMPLETE)
  75                return 0;
  76
  77        if (!tree->buffer) {
  78                enum object_type type;
  79                unsigned long size;
  80                void *data = read_object_file(oid, &type, &size);
  81                if (!data) {
  82                        tree->object.flags |= INCOMPLETE;
  83                        return 0;
  84                }
  85                tree->buffer = data;
  86                tree->size = size;
  87        }
  88        init_tree_desc(&desc, tree->buffer, tree->size);
  89        complete = 1;
  90        while (tree_entry(&desc, &entry)) {
  91                if (!has_sha1_file(entry.oid->hash) ||
  92                    (S_ISDIR(entry.mode) && !tree_is_complete(entry.oid))) {
  93                        tree->object.flags |= INCOMPLETE;
  94                        complete = 0;
  95                }
  96        }
  97        free_tree_buffer(tree);
  98
  99        if (complete)
 100                tree->object.flags |= SEEN;
 101        return complete;
 102}
 103
 104static int commit_is_complete(struct commit *commit)
 105{
 106        struct object_array study;
 107        struct object_array found;
 108        int is_incomplete = 0;
 109        int i;
 110
 111        /* early return */
 112        if (commit->object.flags & SEEN)
 113                return 1;
 114        if (commit->object.flags & INCOMPLETE)
 115                return 0;
 116        /*
 117         * Find all commits that are reachable and are not marked as
 118         * SEEN.  Then make sure the trees and blobs contained are
 119         * complete.  After that, mark these commits also as SEEN.
 120         * If some of the objects that are needed to complete this
 121         * commit are missing, mark this commit as INCOMPLETE.
 122         */
 123        memset(&study, 0, sizeof(study));
 124        memset(&found, 0, sizeof(found));
 125        add_object_array(&commit->object, NULL, &study);
 126        add_object_array(&commit->object, NULL, &found);
 127        commit->object.flags |= STUDYING;
 128        while (study.nr) {
 129                struct commit *c;
 130                struct commit_list *parent;
 131
 132                c = (struct commit *)object_array_pop(&study);
 133                if (!c->object.parsed && !parse_object(the_repository, &c->object.oid))
 134                        c->object.flags |= INCOMPLETE;
 135
 136                if (c->object.flags & INCOMPLETE) {
 137                        is_incomplete = 1;
 138                        break;
 139                }
 140                else if (c->object.flags & SEEN)
 141                        continue;
 142                for (parent = c->parents; parent; parent = parent->next) {
 143                        struct commit *p = parent->item;
 144                        if (p->object.flags & STUDYING)
 145                                continue;
 146                        p->object.flags |= STUDYING;
 147                        add_object_array(&p->object, NULL, &study);
 148                        add_object_array(&p->object, NULL, &found);
 149                }
 150        }
 151        if (!is_incomplete) {
 152                /*
 153                 * make sure all commits in "found" array have all the
 154                 * necessary objects.
 155                 */
 156                for (i = 0; i < found.nr; i++) {
 157                        struct commit *c =
 158                                (struct commit *)found.objects[i].item;
 159                        if (!tree_is_complete(get_commit_tree_oid(c))) {
 160                                is_incomplete = 1;
 161                                c->object.flags |= INCOMPLETE;
 162                        }
 163                }
 164                if (!is_incomplete) {
 165                        /* mark all found commits as complete, iow SEEN */
 166                        for (i = 0; i < found.nr; i++)
 167                                found.objects[i].item->flags |= SEEN;
 168                }
 169        }
 170        /* clear flags from the objects we traversed */
 171        for (i = 0; i < found.nr; i++)
 172                found.objects[i].item->flags &= ~STUDYING;
 173        if (is_incomplete)
 174                commit->object.flags |= INCOMPLETE;
 175        else {
 176                /*
 177                 * If we come here, we have (1) traversed the ancestry chain
 178                 * from the "commit" until we reach SEEN commits (which are
 179                 * known to be complete), and (2) made sure that the commits
 180                 * encountered during the above traversal refer to trees that
 181                 * are complete.  Which means that we know *all* the commits
 182                 * we have seen during this process are complete.
 183                 */
 184                for (i = 0; i < found.nr; i++)
 185                        found.objects[i].item->flags |= SEEN;
 186        }
 187        /* free object arrays */
 188        object_array_clear(&study);
 189        object_array_clear(&found);
 190        return !is_incomplete;
 191}
 192
 193static int keep_entry(struct commit **it, struct object_id *oid)
 194{
 195        struct commit *commit;
 196
 197        if (is_null_oid(oid))
 198                return 1;
 199        commit = lookup_commit_reference_gently(the_repository, oid, 1);
 200        if (!commit)
 201                return 0;
 202
 203        /*
 204         * Make sure everything in this commit exists.
 205         *
 206         * We have walked all the objects reachable from the refs
 207         * and cache earlier.  The commits reachable by this commit
 208         * must meet SEEN commits -- and then we should mark them as
 209         * SEEN as well.
 210         */
 211        if (!commit_is_complete(commit))
 212                return 0;
 213        *it = commit;
 214        return 1;
 215}
 216
 217/*
 218 * Starting from commits in the cb->mark_list, mark commits that are
 219 * reachable from them.  Stop the traversal at commits older than
 220 * the expire_limit and queue them back, so that the caller can call
 221 * us again to restart the traversal with longer expire_limit.
 222 */
 223static void mark_reachable(struct expire_reflog_policy_cb *cb)
 224{
 225        struct commit_list *pending;
 226        timestamp_t expire_limit = cb->mark_limit;
 227        struct commit_list *leftover = NULL;
 228
 229        for (pending = cb->mark_list; pending; pending = pending->next)
 230                pending->item->object.flags &= ~REACHABLE;
 231
 232        pending = cb->mark_list;
 233        while (pending) {
 234                struct commit_list *parent;
 235                struct commit *commit = pop_commit(&pending);
 236                if (commit->object.flags & REACHABLE)
 237                        continue;
 238                if (parse_commit(commit))
 239                        continue;
 240                commit->object.flags |= REACHABLE;
 241                if (commit->date < expire_limit) {
 242                        commit_list_insert(commit, &leftover);
 243                        continue;
 244                }
 245                commit->object.flags |= REACHABLE;
 246                parent = commit->parents;
 247                while (parent) {
 248                        commit = parent->item;
 249                        parent = parent->next;
 250                        if (commit->object.flags & REACHABLE)
 251                                continue;
 252                        commit_list_insert(commit, &pending);
 253                }
 254        }
 255        cb->mark_list = leftover;
 256}
 257
 258static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, struct object_id *oid)
 259{
 260        /*
 261         * We may or may not have the commit yet - if not, look it
 262         * up using the supplied sha1.
 263         */
 264        if (!commit) {
 265                if (is_null_oid(oid))
 266                        return 0;
 267
 268                commit = lookup_commit_reference_gently(the_repository, oid,
 269                                                        1);
 270
 271                /* Not a commit -- keep it */
 272                if (!commit)
 273                        return 0;
 274        }
 275
 276        /* Reachable from the current ref?  Don't prune. */
 277        if (commit->object.flags & REACHABLE)
 278                return 0;
 279
 280        if (cb->mark_list && cb->mark_limit) {
 281                cb->mark_limit = 0; /* dig down to the root */
 282                mark_reachable(cb);
 283        }
 284
 285        return !(commit->object.flags & REACHABLE);
 286}
 287
 288/*
 289 * Return true iff the specified reflog entry should be expired.
 290 */
 291static int should_expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
 292                                    const char *email, timestamp_t timestamp, int tz,
 293                                    const char *message, void *cb_data)
 294{
 295        struct expire_reflog_policy_cb *cb = cb_data;
 296        struct commit *old_commit, *new_commit;
 297
 298        if (timestamp < cb->cmd.expire_total)
 299                return 1;
 300
 301        old_commit = new_commit = NULL;
 302        if (cb->cmd.stalefix &&
 303            (!keep_entry(&old_commit, ooid) || !keep_entry(&new_commit, noid)))
 304                return 1;
 305
 306        if (timestamp < cb->cmd.expire_unreachable) {
 307                if (cb->unreachable_expire_kind == UE_ALWAYS)
 308                        return 1;
 309                if (unreachable(cb, old_commit, ooid) || unreachable(cb, new_commit, noid))
 310                        return 1;
 311        }
 312
 313        if (cb->cmd.recno && --(cb->cmd.recno) == 0)
 314                return 1;
 315
 316        return 0;
 317}
 318
 319static int push_tip_to_list(const char *refname, const struct object_id *oid,
 320                            int flags, void *cb_data)
 321{
 322        struct commit_list **list = cb_data;
 323        struct commit *tip_commit;
 324        if (flags & REF_ISSYMREF)
 325                return 0;
 326        tip_commit = lookup_commit_reference_gently(the_repository, oid, 1);
 327        if (!tip_commit)
 328                return 0;
 329        commit_list_insert(tip_commit, list);
 330        return 0;
 331}
 332
 333static void reflog_expiry_prepare(const char *refname,
 334                                  const struct object_id *oid,
 335                                  void *cb_data)
 336{
 337        struct expire_reflog_policy_cb *cb = cb_data;
 338
 339        if (!cb->cmd.expire_unreachable || !strcmp(refname, "HEAD")) {
 340                cb->tip_commit = NULL;
 341                cb->unreachable_expire_kind = UE_HEAD;
 342        } else {
 343                cb->tip_commit = lookup_commit_reference_gently(the_repository,
 344                                                                oid, 1);
 345                if (!cb->tip_commit)
 346                        cb->unreachable_expire_kind = UE_ALWAYS;
 347                else
 348                        cb->unreachable_expire_kind = UE_NORMAL;
 349        }
 350
 351        if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
 352                cb->unreachable_expire_kind = UE_ALWAYS;
 353
 354        cb->mark_list = NULL;
 355        cb->tips = NULL;
 356        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 357                if (cb->unreachable_expire_kind == UE_HEAD) {
 358                        struct commit_list *elem;
 359
 360                        for_each_ref(push_tip_to_list, &cb->tips);
 361                        for (elem = cb->tips; elem; elem = elem->next)
 362                                commit_list_insert(elem->item, &cb->mark_list);
 363                } else {
 364                        commit_list_insert(cb->tip_commit, &cb->mark_list);
 365                }
 366                cb->mark_limit = cb->cmd.expire_total;
 367                mark_reachable(cb);
 368        }
 369}
 370
 371static void reflog_expiry_cleanup(void *cb_data)
 372{
 373        struct expire_reflog_policy_cb *cb = cb_data;
 374
 375        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 376                if (cb->unreachable_expire_kind == UE_HEAD) {
 377                        struct commit_list *elem;
 378                        for (elem = cb->tips; elem; elem = elem->next)
 379                                clear_commit_marks(elem->item, REACHABLE);
 380                        free_commit_list(cb->tips);
 381                } else {
 382                        clear_commit_marks(cb->tip_commit, REACHABLE);
 383                }
 384        }
 385}
 386
 387static int collect_reflog(const char *ref, const struct object_id *oid, int unused, void *cb_data)
 388{
 389        struct collected_reflog *e;
 390        struct collect_reflog_cb *cb = cb_data;
 391
 392        FLEX_ALLOC_STR(e, reflog, ref);
 393        oidcpy(&e->oid, oid);
 394        ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
 395        cb->e[cb->nr++] = e;
 396        return 0;
 397}
 398
 399static struct reflog_expire_cfg {
 400        struct reflog_expire_cfg *next;
 401        timestamp_t expire_total;
 402        timestamp_t expire_unreachable;
 403        char pattern[FLEX_ARRAY];
 404} *reflog_expire_cfg, **reflog_expire_cfg_tail;
 405
 406static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
 407{
 408        struct reflog_expire_cfg *ent;
 409
 410        if (!reflog_expire_cfg_tail)
 411                reflog_expire_cfg_tail = &reflog_expire_cfg;
 412
 413        for (ent = reflog_expire_cfg; ent; ent = ent->next)
 414                if (!strncmp(ent->pattern, pattern, len) &&
 415                    ent->pattern[len] == '\0')
 416                        return ent;
 417
 418        FLEX_ALLOC_MEM(ent, pattern, pattern, len);
 419        *reflog_expire_cfg_tail = ent;
 420        reflog_expire_cfg_tail = &(ent->next);
 421        return ent;
 422}
 423
 424/* expiry timer slot */
 425#define EXPIRE_TOTAL   01
 426#define EXPIRE_UNREACH 02
 427
 428static int reflog_expire_config(const char *var, const char *value, void *cb)
 429{
 430        const char *pattern, *key;
 431        int pattern_len;
 432        timestamp_t expire;
 433        int slot;
 434        struct reflog_expire_cfg *ent;
 435
 436        if (parse_config_key(var, "gc", &pattern, &pattern_len, &key) < 0)
 437                return git_default_config(var, value, cb);
 438
 439        if (!strcmp(key, "reflogexpire")) {
 440                slot = EXPIRE_TOTAL;
 441                if (git_config_expiry_date(&expire, var, value))
 442                        return -1;
 443        } else if (!strcmp(key, "reflogexpireunreachable")) {
 444                slot = EXPIRE_UNREACH;
 445                if (git_config_expiry_date(&expire, var, value))
 446                        return -1;
 447        } else
 448                return git_default_config(var, value, cb);
 449
 450        if (!pattern) {
 451                switch (slot) {
 452                case EXPIRE_TOTAL:
 453                        default_reflog_expire = expire;
 454                        break;
 455                case EXPIRE_UNREACH:
 456                        default_reflog_expire_unreachable = expire;
 457                        break;
 458                }
 459                return 0;
 460        }
 461
 462        ent = find_cfg_ent(pattern, pattern_len);
 463        if (!ent)
 464                return -1;
 465        switch (slot) {
 466        case EXPIRE_TOTAL:
 467                ent->expire_total = expire;
 468                break;
 469        case EXPIRE_UNREACH:
 470                ent->expire_unreachable = expire;
 471                break;
 472        }
 473        return 0;
 474}
 475
 476static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
 477{
 478        struct reflog_expire_cfg *ent;
 479
 480        if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
 481                return; /* both given explicitly -- nothing to tweak */
 482
 483        for (ent = reflog_expire_cfg; ent; ent = ent->next) {
 484                if (!wildmatch(ent->pattern, ref, 0)) {
 485                        if (!(slot & EXPIRE_TOTAL))
 486                                cb->expire_total = ent->expire_total;
 487                        if (!(slot & EXPIRE_UNREACH))
 488                                cb->expire_unreachable = ent->expire_unreachable;
 489                        return;
 490                }
 491        }
 492
 493        /*
 494         * If unconfigured, make stash never expire
 495         */
 496        if (!strcmp(ref, "refs/stash")) {
 497                if (!(slot & EXPIRE_TOTAL))
 498                        cb->expire_total = 0;
 499                if (!(slot & EXPIRE_UNREACH))
 500                        cb->expire_unreachable = 0;
 501                return;
 502        }
 503
 504        /* Nothing matched -- use the default value */
 505        if (!(slot & EXPIRE_TOTAL))
 506                cb->expire_total = default_reflog_expire;
 507        if (!(slot & EXPIRE_UNREACH))
 508                cb->expire_unreachable = default_reflog_expire_unreachable;
 509}
 510
 511static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 512{
 513        struct expire_reflog_policy_cb cb;
 514        timestamp_t now = time(NULL);
 515        int i, status, do_all;
 516        int explicit_expiry = 0;
 517        unsigned int flags = 0;
 518
 519        default_reflog_expire_unreachable = now - 30 * 24 * 3600;
 520        default_reflog_expire = now - 90 * 24 * 3600;
 521        git_config(reflog_expire_config, NULL);
 522
 523        save_commit_buffer = 0;
 524        do_all = status = 0;
 525        memset(&cb, 0, sizeof(cb));
 526
 527        cb.cmd.expire_total = default_reflog_expire;
 528        cb.cmd.expire_unreachable = default_reflog_expire_unreachable;
 529
 530        for (i = 1; i < argc; i++) {
 531                const char *arg = argv[i];
 532                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 533                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 534                else if (starts_with(arg, "--expire=")) {
 535                        if (parse_expiry_date(arg + 9, &cb.cmd.expire_total))
 536                                die(_("'%s' is not a valid timestamp"), arg);
 537                        explicit_expiry |= EXPIRE_TOTAL;
 538                }
 539                else if (starts_with(arg, "--expire-unreachable=")) {
 540                        if (parse_expiry_date(arg + 21, &cb.cmd.expire_unreachable))
 541                                die(_("'%s' is not a valid timestamp"), arg);
 542                        explicit_expiry |= EXPIRE_UNREACH;
 543                }
 544                else if (!strcmp(arg, "--stale-fix"))
 545                        cb.cmd.stalefix = 1;
 546                else if (!strcmp(arg, "--rewrite"))
 547                        flags |= EXPIRE_REFLOGS_REWRITE;
 548                else if (!strcmp(arg, "--updateref"))
 549                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 550                else if (!strcmp(arg, "--all"))
 551                        do_all = 1;
 552                else if (!strcmp(arg, "--verbose"))
 553                        flags |= EXPIRE_REFLOGS_VERBOSE;
 554                else if (!strcmp(arg, "--")) {
 555                        i++;
 556                        break;
 557                }
 558                else if (arg[0] == '-')
 559                        usage(reflog_expire_usage);
 560                else
 561                        break;
 562        }
 563
 564        /*
 565         * We can trust the commits and objects reachable from refs
 566         * even in older repository.  We cannot trust what's reachable
 567         * from reflog if the repository was pruned with older git.
 568         */
 569        if (cb.cmd.stalefix) {
 570                repo_init_revisions(the_repository, &cb.cmd.revs, prefix);
 571                if (flags & EXPIRE_REFLOGS_VERBOSE)
 572                        printf("Marking reachable objects...");
 573                mark_reachable_objects(&cb.cmd.revs, 0, 0, NULL);
 574                if (flags & EXPIRE_REFLOGS_VERBOSE)
 575                        putchar('\n');
 576        }
 577
 578        if (do_all) {
 579                struct collect_reflog_cb collected;
 580                int i;
 581
 582                memset(&collected, 0, sizeof(collected));
 583                for_each_reflog(collect_reflog, &collected);
 584                for (i = 0; i < collected.nr; i++) {
 585                        struct collected_reflog *e = collected.e[i];
 586                        set_reflog_expiry_param(&cb.cmd, explicit_expiry, e->reflog);
 587                        status |= reflog_expire(e->reflog, &e->oid, flags,
 588                                                reflog_expiry_prepare,
 589                                                should_expire_reflog_ent,
 590                                                reflog_expiry_cleanup,
 591                                                &cb);
 592                        free(e);
 593                }
 594                free(collected.e);
 595        }
 596
 597        for (; i < argc; i++) {
 598                char *ref;
 599                struct object_id oid;
 600                if (!dwim_log(argv[i], strlen(argv[i]), &oid, &ref)) {
 601                        status |= error("%s points nowhere!", argv[i]);
 602                        continue;
 603                }
 604                set_reflog_expiry_param(&cb.cmd, explicit_expiry, ref);
 605                status |= reflog_expire(ref, &oid, flags,
 606                                        reflog_expiry_prepare,
 607                                        should_expire_reflog_ent,
 608                                        reflog_expiry_cleanup,
 609                                        &cb);
 610        }
 611        return status;
 612}
 613
 614static int count_reflog_ent(struct object_id *ooid, struct object_id *noid,
 615                const char *email, timestamp_t timestamp, int tz,
 616                const char *message, void *cb_data)
 617{
 618        struct expire_reflog_policy_cb *cb = cb_data;
 619        if (!cb->cmd.expire_total || timestamp < cb->cmd.expire_total)
 620                cb->cmd.recno++;
 621        return 0;
 622}
 623
 624static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 625{
 626        struct expire_reflog_policy_cb cb;
 627        int i, status = 0;
 628        unsigned int flags = 0;
 629
 630        memset(&cb, 0, sizeof(cb));
 631
 632        for (i = 1; i < argc; i++) {
 633                const char *arg = argv[i];
 634                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 635                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 636                else if (!strcmp(arg, "--rewrite"))
 637                        flags |= EXPIRE_REFLOGS_REWRITE;
 638                else if (!strcmp(arg, "--updateref"))
 639                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 640                else if (!strcmp(arg, "--verbose"))
 641                        flags |= EXPIRE_REFLOGS_VERBOSE;
 642                else if (!strcmp(arg, "--")) {
 643                        i++;
 644                        break;
 645                }
 646                else if (arg[0] == '-')
 647                        usage(reflog_delete_usage);
 648                else
 649                        break;
 650        }
 651
 652        if (argc - i < 1)
 653                return error("Nothing to delete?");
 654
 655        for ( ; i < argc; i++) {
 656                const char *spec = strstr(argv[i], "@{");
 657                struct object_id oid;
 658                char *ep, *ref;
 659                int recno;
 660
 661                if (!spec) {
 662                        status |= error("Not a reflog: %s", argv[i]);
 663                        continue;
 664                }
 665
 666                if (!dwim_log(argv[i], spec - argv[i], &oid, &ref)) {
 667                        status |= error("no reflog for '%s'", argv[i]);
 668                        continue;
 669                }
 670
 671                recno = strtoul(spec + 2, &ep, 10);
 672                if (*ep == '}') {
 673                        cb.cmd.recno = -recno;
 674                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 675                } else {
 676                        cb.cmd.expire_total = approxidate(spec + 2);
 677                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 678                        cb.cmd.expire_total = 0;
 679                }
 680
 681                status |= reflog_expire(ref, &oid, flags,
 682                                        reflog_expiry_prepare,
 683                                        should_expire_reflog_ent,
 684                                        reflog_expiry_cleanup,
 685                                        &cb);
 686                free(ref);
 687        }
 688        return status;
 689}
 690
 691static int cmd_reflog_exists(int argc, const char **argv, const char *prefix)
 692{
 693        int i, start = 0;
 694
 695        for (i = 1; i < argc; i++) {
 696                const char *arg = argv[i];
 697                if (!strcmp(arg, "--")) {
 698                        i++;
 699                        break;
 700                }
 701                else if (arg[0] == '-')
 702                        usage(reflog_exists_usage);
 703                else
 704                        break;
 705        }
 706
 707        start = i;
 708
 709        if (argc - start != 1)
 710                usage(reflog_exists_usage);
 711
 712        if (check_refname_format(argv[start], REFNAME_ALLOW_ONELEVEL))
 713                die("invalid ref format: %s", argv[start]);
 714        return !reflog_exists(argv[start]);
 715}
 716
 717/*
 718 * main "reflog"
 719 */
 720
 721static const char reflog_usage[] =
 722"git reflog [ show | expire | delete | exists ]";
 723
 724int cmd_reflog(int argc, const char **argv, const char *prefix)
 725{
 726        if (argc > 1 && !strcmp(argv[1], "-h"))
 727                usage(reflog_usage);
 728
 729        /* With no command, we default to showing it. */
 730        if (argc < 2 || *argv[1] == '-')
 731                return cmd_log_reflog(argc, argv, prefix);
 732
 733        if (!strcmp(argv[1], "show"))
 734                return cmd_log_reflog(argc - 1, argv + 1, prefix);
 735
 736        if (!strcmp(argv[1], "expire"))
 737                return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 738
 739        if (!strcmp(argv[1], "delete"))
 740                return cmd_reflog_delete(argc - 1, argv + 1, prefix);
 741
 742        if (!strcmp(argv[1], "exists"))
 743                return cmd_reflog_exists(argc - 1, argv + 1, prefix);
 744
 745        return cmd_log_reflog(argc, argv, prefix);
 746}