Andrew's git / gitweb.git / builtin/reflog.c
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builtin / reflog.con commit fmt-merge-msg: add function to append shortlog only (8c6bdfd)
   1#include "cache.h"
   2#include "builtin.h"
   3#include "commit.h"
   4#include "refs.h"
   5#include "dir.h"
   6#include "tree-walk.h"
   7#include "diff.h"
   8#include "revision.h"
   9#include "reachable.h"
  10
  11/*
  12 * reflog expire
  13 */
  14
  15static const char reflog_expire_usage[] =
  16"git reflog expire [--verbose] [--dry-run] [--stale-fix] [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...";
  17static const char reflog_delete_usage[] =
  18"git reflog delete [--verbose] [--dry-run] [--rewrite] [--updateref] <refs>...";
  19
  20static unsigned long default_reflog_expire;
  21static unsigned long default_reflog_expire_unreachable;
  22
  23struct cmd_reflog_expire_cb {
  24        struct rev_info revs;
  25        int dry_run;
  26        int stalefix;
  27        int rewrite;
  28        int updateref;
  29        int verbose;
  30        unsigned long expire_total;
  31        unsigned long expire_unreachable;
  32        int recno;
  33};
  34
  35struct expire_reflog_cb {
  36        FILE *newlog;
  37        const char *ref;
  38        struct commit *ref_commit;
  39        struct cmd_reflog_expire_cb *cmd;
  40        unsigned char last_kept_sha1[20];
  41};
  42
  43struct collected_reflog {
  44        unsigned char sha1[20];
  45        char reflog[FLEX_ARRAY];
  46};
  47struct collect_reflog_cb {
  48        struct collected_reflog **e;
  49        int alloc;
  50        int nr;
  51};
  52
  53#define INCOMPLETE      (1u<<10)
  54#define STUDYING        (1u<<11)
  55#define REACHABLE       (1u<<12)
  56
  57static int tree_is_complete(const unsigned char *sha1)
  58{
  59        struct tree_desc desc;
  60        struct name_entry entry;
  61        int complete;
  62        struct tree *tree;
  63
  64        tree = lookup_tree(sha1);
  65        if (!tree)
  66                return 0;
  67        if (tree->object.flags & SEEN)
  68                return 1;
  69        if (tree->object.flags & INCOMPLETE)
  70                return 0;
  71
  72        if (!tree->buffer) {
  73                enum object_type type;
  74                unsigned long size;
  75                void *data = read_sha1_file(sha1, &type, &size);
  76                if (!data) {
  77                        tree->object.flags |= INCOMPLETE;
  78                        return 0;
  79                }
  80                tree->buffer = data;
  81                tree->size = size;
  82        }
  83        init_tree_desc(&desc, tree->buffer, tree->size);
  84        complete = 1;
  85        while (tree_entry(&desc, &entry)) {
  86                if (!has_sha1_file(entry.sha1) ||
  87                    (S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
  88                        tree->object.flags |= INCOMPLETE;
  89                        complete = 0;
  90                }
  91        }
  92        free(tree->buffer);
  93        tree->buffer = NULL;
  94
  95        if (complete)
  96                tree->object.flags |= SEEN;
  97        return complete;
  98}
  99
 100static int commit_is_complete(struct commit *commit)
 101{
 102        struct object_array study;
 103        struct object_array found;
 104        int is_incomplete = 0;
 105        int i;
 106
 107        /* early return */
 108        if (commit->object.flags & SEEN)
 109                return 1;
 110        if (commit->object.flags & INCOMPLETE)
 111                return 0;
 112        /*
 113         * Find all commits that are reachable and are not marked as
 114         * SEEN.  Then make sure the trees and blobs contained are
 115         * complete.  After that, mark these commits also as SEEN.
 116         * If some of the objects that are needed to complete this
 117         * commit are missing, mark this commit as INCOMPLETE.
 118         */
 119        memset(&study, 0, sizeof(study));
 120        memset(&found, 0, sizeof(found));
 121        add_object_array(&commit->object, NULL, &study);
 122        add_object_array(&commit->object, NULL, &found);
 123        commit->object.flags |= STUDYING;
 124        while (study.nr) {
 125                struct commit *c;
 126                struct commit_list *parent;
 127
 128                c = (struct commit *)study.objects[--study.nr].item;
 129                if (!c->object.parsed && !parse_object(c->object.sha1))
 130                        c->object.flags |= INCOMPLETE;
 131
 132                if (c->object.flags & INCOMPLETE) {
 133                        is_incomplete = 1;
 134                        break;
 135                }
 136                else if (c->object.flags & SEEN)
 137                        continue;
 138                for (parent = c->parents; parent; parent = parent->next) {
 139                        struct commit *p = parent->item;
 140                        if (p->object.flags & STUDYING)
 141                                continue;
 142                        p->object.flags |= STUDYING;
 143                        add_object_array(&p->object, NULL, &study);
 144                        add_object_array(&p->object, NULL, &found);
 145                }
 146        }
 147        if (!is_incomplete) {
 148                /*
 149                 * make sure all commits in "found" array have all the
 150                 * necessary objects.
 151                 */
 152                for (i = 0; i < found.nr; i++) {
 153                        struct commit *c =
 154                                (struct commit *)found.objects[i].item;
 155                        if (!tree_is_complete(c->tree->object.sha1)) {
 156                                is_incomplete = 1;
 157                                c->object.flags |= INCOMPLETE;
 158                        }
 159                }
 160                if (!is_incomplete) {
 161                        /* mark all found commits as complete, iow SEEN */
 162                        for (i = 0; i < found.nr; i++)
 163                                found.objects[i].item->flags |= SEEN;
 164                }
 165        }
 166        /* clear flags from the objects we traversed */
 167        for (i = 0; i < found.nr; i++)
 168                found.objects[i].item->flags &= ~STUDYING;
 169        if (is_incomplete)
 170                commit->object.flags |= INCOMPLETE;
 171        else {
 172                /*
 173                 * If we come here, we have (1) traversed the ancestry chain
 174                 * from the "commit" until we reach SEEN commits (which are
 175                 * known to be complete), and (2) made sure that the commits
 176                 * encountered during the above traversal refer to trees that
 177                 * are complete.  Which means that we know *all* the commits
 178                 * we have seen during this process are complete.
 179                 */
 180                for (i = 0; i < found.nr; i++)
 181                        found.objects[i].item->flags |= SEEN;
 182        }
 183        /* free object arrays */
 184        free(study.objects);
 185        free(found.objects);
 186        return !is_incomplete;
 187}
 188
 189static int keep_entry(struct commit **it, unsigned char *sha1)
 190{
 191        struct commit *commit;
 192
 193        if (is_null_sha1(sha1))
 194                return 1;
 195        commit = lookup_commit_reference_gently(sha1, 1);
 196        if (!commit)
 197                return 0;
 198
 199        /*
 200         * Make sure everything in this commit exists.
 201         *
 202         * We have walked all the objects reachable from the refs
 203         * and cache earlier.  The commits reachable by this commit
 204         * must meet SEEN commits -- and then we should mark them as
 205         * SEEN as well.
 206         */
 207        if (!commit_is_complete(commit))
 208                return 0;
 209        *it = commit;
 210        return 1;
 211}
 212
 213static int unreachable(struct expire_reflog_cb *cb, struct commit *commit, unsigned char *sha1)
 214{
 215        /*
 216         * We may or may not have the commit yet - if not, look it
 217         * up using the supplied sha1.
 218         */
 219        if (!commit) {
 220                if (is_null_sha1(sha1))
 221                        return 0;
 222
 223                commit = lookup_commit_reference_gently(sha1, 1);
 224
 225                /* Not a commit -- keep it */
 226                if (!commit)
 227                        return 0;
 228        }
 229
 230        /* Reachable from the current ref?  Don't prune. */
 231        if (commit->object.flags & REACHABLE)
 232                return 0;
 233        if (in_merge_bases(commit, &cb->ref_commit, 1))
 234                return 0;
 235
 236        /* We can't reach it - prune it. */
 237        return 1;
 238}
 239
 240static void mark_reachable(struct commit *commit, unsigned long expire_limit)
 241{
 242        /*
 243         * We need to compute whether the commit on either side of a reflog
 244         * entry is reachable from the tip of the ref for all entries.
 245         * Mark commits that are reachable from the tip down to the
 246         * time threshold first; we know a commit marked thusly is
 247         * reachable from the tip without running in_merge_bases()
 248         * at all.
 249         */
 250        struct commit_list *pending = NULL;
 251
 252        commit_list_insert(commit, &pending);
 253        while (pending) {
 254                struct commit_list *entry = pending;
 255                struct commit_list *parent;
 256                pending = entry->next;
 257                commit = entry->item;
 258                free(entry);
 259                if (commit->object.flags & REACHABLE)
 260                        continue;
 261                if (parse_commit(commit))
 262                        continue;
 263                commit->object.flags |= REACHABLE;
 264                if (commit->date < expire_limit)
 265                        continue;
 266                parent = commit->parents;
 267                while (parent) {
 268                        commit = parent->item;
 269                        parent = parent->next;
 270                        if (commit->object.flags & REACHABLE)
 271                                continue;
 272                        commit_list_insert(commit, &pending);
 273                }
 274        }
 275}
 276
 277static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 278                const char *email, unsigned long timestamp, int tz,
 279                const char *message, void *cb_data)
 280{
 281        struct expire_reflog_cb *cb = cb_data;
 282        struct commit *old, *new;
 283
 284        if (timestamp < cb->cmd->expire_total)
 285                goto prune;
 286
 287        if (cb->cmd->rewrite)
 288                osha1 = cb->last_kept_sha1;
 289
 290        old = new = NULL;
 291        if (cb->cmd->stalefix &&
 292            (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
 293                goto prune;
 294
 295        if (timestamp < cb->cmd->expire_unreachable) {
 296                if (!cb->ref_commit)
 297                        goto prune;
 298                if (unreachable(cb, old, osha1) || unreachable(cb, new, nsha1))
 299                        goto prune;
 300        }
 301
 302        if (cb->cmd->recno && --(cb->cmd->recno) == 0)
 303                goto prune;
 304
 305        if (cb->newlog) {
 306                char sign = (tz < 0) ? '-' : '+';
 307                int zone = (tz < 0) ? (-tz) : tz;
 308                fprintf(cb->newlog, "%s %s %s %lu %c%04d\t%s",
 309                        sha1_to_hex(osha1), sha1_to_hex(nsha1),
 310                        email, timestamp, sign, zone,
 311                        message);
 312                hashcpy(cb->last_kept_sha1, nsha1);
 313        }
 314        if (cb->cmd->verbose)
 315                printf("keep %s", message);
 316        return 0;
 317 prune:
 318        if (!cb->newlog || cb->cmd->verbose)
 319                printf("%sprune %s", cb->newlog ? "" : "would ", message);
 320        return 0;
 321}
 322
 323static int expire_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
 324{
 325        struct cmd_reflog_expire_cb *cmd = cb_data;
 326        struct expire_reflog_cb cb;
 327        struct ref_lock *lock;
 328        char *log_file, *newlog_path = NULL;
 329        int status = 0;
 330
 331        memset(&cb, 0, sizeof(cb));
 332
 333        /*
 334         * we take the lock for the ref itself to prevent it from
 335         * getting updated.
 336         */
 337        lock = lock_any_ref_for_update(ref, sha1, 0);
 338        if (!lock)
 339                return error("cannot lock ref '%s'", ref);
 340        log_file = git_pathdup("logs/%s", ref);
 341        if (!file_exists(log_file))
 342                goto finish;
 343        if (!cmd->dry_run) {
 344                newlog_path = git_pathdup("logs/%s.lock", ref);
 345                cb.newlog = fopen(newlog_path, "w");
 346        }
 347
 348        cb.ref_commit = lookup_commit_reference_gently(sha1, 1);
 349        cb.ref = ref;
 350        cb.cmd = cmd;
 351        if (cb.ref_commit)
 352                mark_reachable(cb.ref_commit, cmd->expire_total);
 353        for_each_reflog_ent(ref, expire_reflog_ent, &cb);
 354        if (cb.ref_commit)
 355                clear_commit_marks(cb.ref_commit, REACHABLE);
 356 finish:
 357        if (cb.newlog) {
 358                if (fclose(cb.newlog)) {
 359                        status |= error("%s: %s", strerror(errno),
 360                                        newlog_path);
 361                        unlink(newlog_path);
 362                } else if (cmd->updateref &&
 363                        (write_in_full(lock->lock_fd,
 364                                sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
 365                         write_str_in_full(lock->lock_fd, "\n") != 1 ||
 366                         close_ref(lock) < 0)) {
 367                        status |= error("Couldn't write %s",
 368                                lock->lk->filename);
 369                        unlink(newlog_path);
 370                } else if (rename(newlog_path, log_file)) {
 371                        status |= error("cannot rename %s to %s",
 372                                        newlog_path, log_file);
 373                        unlink(newlog_path);
 374                } else if (cmd->updateref && commit_ref(lock)) {
 375                        status |= error("Couldn't set %s", lock->ref_name);
 376                } else {
 377                        adjust_shared_perm(log_file);
 378                }
 379        }
 380        free(newlog_path);
 381        free(log_file);
 382        unlock_ref(lock);
 383        return status;
 384}
 385
 386static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
 387{
 388        struct collected_reflog *e;
 389        struct collect_reflog_cb *cb = cb_data;
 390        size_t namelen = strlen(ref);
 391
 392        e = xmalloc(sizeof(*e) + namelen + 1);
 393        hashcpy(e->sha1, sha1);
 394        memcpy(e->reflog, ref, namelen + 1);
 395        ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
 396        cb->e[cb->nr++] = e;
 397        return 0;
 398}
 399
 400static struct reflog_expire_cfg {
 401        struct reflog_expire_cfg *next;
 402        unsigned long expire_total;
 403        unsigned long expire_unreachable;
 404        size_t len;
 405        char pattern[FLEX_ARRAY];
 406} *reflog_expire_cfg, **reflog_expire_cfg_tail;
 407
 408static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
 409{
 410        struct reflog_expire_cfg *ent;
 411
 412        if (!reflog_expire_cfg_tail)
 413                reflog_expire_cfg_tail = &reflog_expire_cfg;
 414
 415        for (ent = reflog_expire_cfg; ent; ent = ent->next)
 416                if (ent->len == len &&
 417                    !memcmp(ent->pattern, pattern, len))
 418                        return ent;
 419
 420        ent = xcalloc(1, (sizeof(*ent) + len));
 421        memcpy(ent->pattern, pattern, len);
 422        ent->len = len;
 423        *reflog_expire_cfg_tail = ent;
 424        reflog_expire_cfg_tail = &(ent->next);
 425        return ent;
 426}
 427
 428static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
 429{
 430        if (!value)
 431                return config_error_nonbool(var);
 432        if (!strcmp(value, "never") || !strcmp(value, "false")) {
 433                *expire = 0;
 434                return 0;
 435        }
 436        *expire = approxidate(value);
 437        return 0;
 438}
 439
 440/* expiry timer slot */
 441#define EXPIRE_TOTAL   01
 442#define EXPIRE_UNREACH 02
 443
 444static int reflog_expire_config(const char *var, const char *value, void *cb)
 445{
 446        const char *lastdot = strrchr(var, '.');
 447        unsigned long expire;
 448        int slot;
 449        struct reflog_expire_cfg *ent;
 450
 451        if (!lastdot || prefixcmp(var, "gc."))
 452                return git_default_config(var, value, cb);
 453
 454        if (!strcmp(lastdot, ".reflogexpire")) {
 455                slot = EXPIRE_TOTAL;
 456                if (parse_expire_cfg_value(var, value, &expire))
 457                        return -1;
 458        } else if (!strcmp(lastdot, ".reflogexpireunreachable")) {
 459                slot = EXPIRE_UNREACH;
 460                if (parse_expire_cfg_value(var, value, &expire))
 461                        return -1;
 462        } else
 463                return git_default_config(var, value, cb);
 464
 465        if (lastdot == var + 2) {
 466                switch (slot) {
 467                case EXPIRE_TOTAL:
 468                        default_reflog_expire = expire;
 469                        break;
 470                case EXPIRE_UNREACH:
 471                        default_reflog_expire_unreachable = expire;
 472                        break;
 473                }
 474                return 0;
 475        }
 476
 477        ent = find_cfg_ent(var + 3, lastdot - (var+3));
 478        if (!ent)
 479                return -1;
 480        switch (slot) {
 481        case EXPIRE_TOTAL:
 482                ent->expire_total = expire;
 483                break;
 484        case EXPIRE_UNREACH:
 485                ent->expire_unreachable = expire;
 486                break;
 487        }
 488        return 0;
 489}
 490
 491static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
 492{
 493        struct reflog_expire_cfg *ent;
 494
 495        if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
 496                return; /* both given explicitly -- nothing to tweak */
 497
 498        for (ent = reflog_expire_cfg; ent; ent = ent->next) {
 499                if (!fnmatch(ent->pattern, ref, 0)) {
 500                        if (!(slot & EXPIRE_TOTAL))
 501                                cb->expire_total = ent->expire_total;
 502                        if (!(slot & EXPIRE_UNREACH))
 503                                cb->expire_unreachable = ent->expire_unreachable;
 504                        return;
 505                }
 506        }
 507
 508        /*
 509         * If unconfigured, make stash never expire
 510         */
 511        if (!strcmp(ref, "refs/stash")) {
 512                if (!(slot & EXPIRE_TOTAL))
 513                        cb->expire_total = 0;
 514                if (!(slot & EXPIRE_UNREACH))
 515                        cb->expire_unreachable = 0;
 516                return;
 517        }
 518
 519        /* Nothing matched -- use the default value */
 520        if (!(slot & EXPIRE_TOTAL))
 521                cb->expire_total = default_reflog_expire;
 522        if (!(slot & EXPIRE_UNREACH))
 523                cb->expire_unreachable = default_reflog_expire_unreachable;
 524}
 525
 526static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 527{
 528        struct cmd_reflog_expire_cb cb;
 529        unsigned long now = time(NULL);
 530        int i, status, do_all;
 531        int explicit_expiry = 0;
 532
 533        default_reflog_expire_unreachable = now - 30 * 24 * 3600;
 534        default_reflog_expire = now - 90 * 24 * 3600;
 535        git_config(reflog_expire_config, NULL);
 536
 537        save_commit_buffer = 0;
 538        do_all = status = 0;
 539        memset(&cb, 0, sizeof(cb));
 540
 541        cb.expire_total = default_reflog_expire;
 542        cb.expire_unreachable = default_reflog_expire_unreachable;
 543
 544        for (i = 1; i < argc; i++) {
 545                const char *arg = argv[i];
 546                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 547                        cb.dry_run = 1;
 548                else if (!prefixcmp(arg, "--expire=")) {
 549                        cb.expire_total = approxidate(arg + 9);
 550                        explicit_expiry |= EXPIRE_TOTAL;
 551                }
 552                else if (!prefixcmp(arg, "--expire-unreachable=")) {
 553                        cb.expire_unreachable = approxidate(arg + 21);
 554                        explicit_expiry |= EXPIRE_UNREACH;
 555                }
 556                else if (!strcmp(arg, "--stale-fix"))
 557                        cb.stalefix = 1;
 558                else if (!strcmp(arg, "--rewrite"))
 559                        cb.rewrite = 1;
 560                else if (!strcmp(arg, "--updateref"))
 561                        cb.updateref = 1;
 562                else if (!strcmp(arg, "--all"))
 563                        do_all = 1;
 564                else if (!strcmp(arg, "--verbose"))
 565                        cb.verbose = 1;
 566                else if (!strcmp(arg, "--")) {
 567                        i++;
 568                        break;
 569                }
 570                else if (arg[0] == '-')
 571                        usage(reflog_expire_usage);
 572                else
 573                        break;
 574        }
 575
 576        /*
 577         * We can trust the commits and objects reachable from refs
 578         * even in older repository.  We cannot trust what's reachable
 579         * from reflog if the repository was pruned with older git.
 580         */
 581        if (cb.stalefix) {
 582                init_revisions(&cb.revs, prefix);
 583                if (cb.verbose)
 584                        printf("Marking reachable objects...");
 585                mark_reachable_objects(&cb.revs, 0);
 586                if (cb.verbose)
 587                        putchar('\n');
 588        }
 589
 590        if (do_all) {
 591                struct collect_reflog_cb collected;
 592                int i;
 593
 594                memset(&collected, 0, sizeof(collected));
 595                for_each_reflog(collect_reflog, &collected);
 596                for (i = 0; i < collected.nr; i++) {
 597                        struct collected_reflog *e = collected.e[i];
 598                        set_reflog_expiry_param(&cb, explicit_expiry, e->reflog);
 599                        status |= expire_reflog(e->reflog, e->sha1, 0, &cb);
 600                        free(e);
 601                }
 602                free(collected.e);
 603        }
 604
 605        for (; i < argc; i++) {
 606                char *ref;
 607                unsigned char sha1[20];
 608                if (!dwim_log(argv[i], strlen(argv[i]), sha1, &ref)) {
 609                        status |= error("%s points nowhere!", argv[i]);
 610                        continue;
 611                }
 612                set_reflog_expiry_param(&cb, explicit_expiry, ref);
 613                status |= expire_reflog(ref, sha1, 0, &cb);
 614        }
 615        return status;
 616}
 617
 618static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 619                const char *email, unsigned long timestamp, int tz,
 620                const char *message, void *cb_data)
 621{
 622        struct cmd_reflog_expire_cb *cb = cb_data;
 623        if (!cb->expire_total || timestamp < cb->expire_total)
 624                cb->recno++;
 625        return 0;
 626}
 627
 628static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 629{
 630        struct cmd_reflog_expire_cb cb;
 631        int i, status = 0;
 632
 633        memset(&cb, 0, sizeof(cb));
 634
 635        for (i = 1; i < argc; i++) {
 636                const char *arg = argv[i];
 637                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 638                        cb.dry_run = 1;
 639                else if (!strcmp(arg, "--rewrite"))
 640                        cb.rewrite = 1;
 641                else if (!strcmp(arg, "--updateref"))
 642                        cb.updateref = 1;
 643                else if (!strcmp(arg, "--verbose"))
 644                        cb.verbose = 1;
 645                else if (!strcmp(arg, "--")) {
 646                        i++;
 647                        break;
 648                }
 649                else if (arg[0] == '-')
 650                        usage(reflog_delete_usage);
 651                else
 652                        break;
 653        }
 654
 655        if (argc - i < 1)
 656                return error("Nothing to delete?");
 657
 658        for ( ; i < argc; i++) {
 659                const char *spec = strstr(argv[i], "@{");
 660                unsigned char sha1[20];
 661                char *ep, *ref;
 662                int recno;
 663
 664                if (!spec) {
 665                        status |= error("Not a reflog: %s", argv[i]);
 666                        continue;
 667                }
 668
 669                if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
 670                        status |= error("no reflog for '%s'", argv[i]);
 671                        continue;
 672                }
 673
 674                recno = strtoul(spec + 2, &ep, 10);
 675                if (*ep == '}') {
 676                        cb.recno = -recno;
 677                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 678                } else {
 679                        cb.expire_total = approxidate(spec + 2);
 680                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 681                        cb.expire_total = 0;
 682                }
 683
 684                status |= expire_reflog(ref, sha1, 0, &cb);
 685                free(ref);
 686        }
 687        return status;
 688}
 689
 690/*
 691 * main "reflog"
 692 */
 693
 694static const char reflog_usage[] =
 695"git reflog [ show | expire | delete ]";
 696
 697int cmd_reflog(int argc, const char **argv, const char *prefix)
 698{
 699        if (argc > 1 && !strcmp(argv[1], "-h"))
 700                usage(reflog_usage);
 701
 702        /* With no command, we default to showing it. */
 703        if (argc < 2 || *argv[1] == '-')
 704                return cmd_log_reflog(argc, argv, prefix);
 705
 706        if (!strcmp(argv[1], "show"))
 707                return cmd_log_reflog(argc - 1, argv + 1, prefix);
 708
 709        if (!strcmp(argv[1], "expire"))
 710                return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 711
 712        if (!strcmp(argv[1], "delete"))
 713                return cmd_reflog_delete(argc - 1, argv + 1, prefix);
 714
 715        /* Not a recognized reflog command..*/
 716        usage(reflog_usage);
 717}