Andrew's git / gitweb.git / builtin/reflog.c
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builtin / reflog.con commit Merge branch 'ma/parse-maybe-bool' (bdfcdef)
   1#include "builtin.h"
   2#include "config.h"
   3#include "lockfile.h"
   4#include "commit.h"
   5#include "refs.h"
   6#include "dir.h"
   7#include "tree-walk.h"
   8#include "diff.h"
   9#include "revision.h"
  10#include "reachable.h"
  11
  12/* NEEDSWORK: switch to using parse_options */
  13static const char reflog_expire_usage[] =
  14"git reflog expire [--expire=<time>] [--expire-unreachable=<time>] [--rewrite] [--updateref] [--stale-fix] [--dry-run | -n] [--verbose] [--all] <refs>...";
  15static const char reflog_delete_usage[] =
  16"git reflog delete [--rewrite] [--updateref] [--dry-run | -n] [--verbose] <refs>...";
  17static const char reflog_exists_usage[] =
  18"git reflog exists <ref>";
  19
  20static timestamp_t default_reflog_expire;
  21static timestamp_t default_reflog_expire_unreachable;
  22
  23struct cmd_reflog_expire_cb {
  24        struct rev_info revs;
  25        int stalefix;
  26        timestamp_t expire_total;
  27        timestamp_t expire_unreachable;
  28        int recno;
  29};
  30
  31struct expire_reflog_policy_cb {
  32        enum {
  33                UE_NORMAL,
  34                UE_ALWAYS,
  35                UE_HEAD
  36        } unreachable_expire_kind;
  37        struct commit_list *mark_list;
  38        unsigned long mark_limit;
  39        struct cmd_reflog_expire_cb cmd;
  40        struct commit *tip_commit;
  41        struct commit_list *tips;
  42};
  43
  44struct collected_reflog {
  45        unsigned char sha1[20];
  46        char reflog[FLEX_ARRAY];
  47};
  48
  49struct collect_reflog_cb {
  50        struct collected_reflog **e;
  51        int alloc;
  52        int nr;
  53};
  54
  55#define INCOMPLETE      (1u<<10)
  56#define STUDYING        (1u<<11)
  57#define REACHABLE       (1u<<12)
  58
  59static int tree_is_complete(const struct object_id *oid)
  60{
  61        struct tree_desc desc;
  62        struct name_entry entry;
  63        int complete;
  64        struct tree *tree;
  65
  66        tree = lookup_tree(oid);
  67        if (!tree)
  68                return 0;
  69        if (tree->object.flags & SEEN)
  70                return 1;
  71        if (tree->object.flags & INCOMPLETE)
  72                return 0;
  73
  74        if (!tree->buffer) {
  75                enum object_type type;
  76                unsigned long size;
  77                void *data = read_sha1_file(oid->hash, &type, &size);
  78                if (!data) {
  79                        tree->object.flags |= INCOMPLETE;
  80                        return 0;
  81                }
  82                tree->buffer = data;
  83                tree->size = size;
  84        }
  85        init_tree_desc(&desc, tree->buffer, tree->size);
  86        complete = 1;
  87        while (tree_entry(&desc, &entry)) {
  88                if (!has_sha1_file(entry.oid->hash) ||
  89                    (S_ISDIR(entry.mode) && !tree_is_complete(entry.oid))) {
  90                        tree->object.flags |= INCOMPLETE;
  91                        complete = 0;
  92                }
  93        }
  94        free_tree_buffer(tree);
  95
  96        if (complete)
  97                tree->object.flags |= SEEN;
  98        return complete;
  99}
 100
 101static int commit_is_complete(struct commit *commit)
 102{
 103        struct object_array study;
 104        struct object_array found;
 105        int is_incomplete = 0;
 106        int i;
 107
 108        /* early return */
 109        if (commit->object.flags & SEEN)
 110                return 1;
 111        if (commit->object.flags & INCOMPLETE)
 112                return 0;
 113        /*
 114         * Find all commits that are reachable and are not marked as
 115         * SEEN.  Then make sure the trees and blobs contained are
 116         * complete.  After that, mark these commits also as SEEN.
 117         * If some of the objects that are needed to complete this
 118         * commit are missing, mark this commit as INCOMPLETE.
 119         */
 120        memset(&study, 0, sizeof(study));
 121        memset(&found, 0, sizeof(found));
 122        add_object_array(&commit->object, NULL, &study);
 123        add_object_array(&commit->object, NULL, &found);
 124        commit->object.flags |= STUDYING;
 125        while (study.nr) {
 126                struct commit *c;
 127                struct commit_list *parent;
 128
 129                c = (struct commit *)study.objects[--study.nr].item;
 130                if (!c->object.parsed && !parse_object(&c->object.oid))
 131                        c->object.flags |= INCOMPLETE;
 132
 133                if (c->object.flags & INCOMPLETE) {
 134                        is_incomplete = 1;
 135                        break;
 136                }
 137                else if (c->object.flags & SEEN)
 138                        continue;
 139                for (parent = c->parents; parent; parent = parent->next) {
 140                        struct commit *p = parent->item;
 141                        if (p->object.flags & STUDYING)
 142                                continue;
 143                        p->object.flags |= STUDYING;
 144                        add_object_array(&p->object, NULL, &study);
 145                        add_object_array(&p->object, NULL, &found);
 146                }
 147        }
 148        if (!is_incomplete) {
 149                /*
 150                 * make sure all commits in "found" array have all the
 151                 * necessary objects.
 152                 */
 153                for (i = 0; i < found.nr; i++) {
 154                        struct commit *c =
 155                                (struct commit *)found.objects[i].item;
 156                        if (!tree_is_complete(&c->tree->object.oid)) {
 157                                is_incomplete = 1;
 158                                c->object.flags |= INCOMPLETE;
 159                        }
 160                }
 161                if (!is_incomplete) {
 162                        /* mark all found commits as complete, iow SEEN */
 163                        for (i = 0; i < found.nr; i++)
 164                                found.objects[i].item->flags |= SEEN;
 165                }
 166        }
 167        /* clear flags from the objects we traversed */
 168        for (i = 0; i < found.nr; i++)
 169                found.objects[i].item->flags &= ~STUDYING;
 170        if (is_incomplete)
 171                commit->object.flags |= INCOMPLETE;
 172        else {
 173                /*
 174                 * If we come here, we have (1) traversed the ancestry chain
 175                 * from the "commit" until we reach SEEN commits (which are
 176                 * known to be complete), and (2) made sure that the commits
 177                 * encountered during the above traversal refer to trees that
 178                 * are complete.  Which means that we know *all* the commits
 179                 * we have seen during this process are complete.
 180                 */
 181                for (i = 0; i < found.nr; i++)
 182                        found.objects[i].item->flags |= SEEN;
 183        }
 184        /* free object arrays */
 185        free(study.objects);
 186        free(found.objects);
 187        return !is_incomplete;
 188}
 189
 190static int keep_entry(struct commit **it, struct object_id *oid)
 191{
 192        struct commit *commit;
 193
 194        if (is_null_oid(oid))
 195                return 1;
 196        commit = lookup_commit_reference_gently(oid, 1);
 197        if (!commit)
 198                return 0;
 199
 200        /*
 201         * Make sure everything in this commit exists.
 202         *
 203         * We have walked all the objects reachable from the refs
 204         * and cache earlier.  The commits reachable by this commit
 205         * must meet SEEN commits -- and then we should mark them as
 206         * SEEN as well.
 207         */
 208        if (!commit_is_complete(commit))
 209                return 0;
 210        *it = commit;
 211        return 1;
 212}
 213
 214/*
 215 * Starting from commits in the cb->mark_list, mark commits that are
 216 * reachable from them.  Stop the traversal at commits older than
 217 * the expire_limit and queue them back, so that the caller can call
 218 * us again to restart the traversal with longer expire_limit.
 219 */
 220static void mark_reachable(struct expire_reflog_policy_cb *cb)
 221{
 222        struct commit_list *pending;
 223        timestamp_t expire_limit = cb->mark_limit;
 224        struct commit_list *leftover = NULL;
 225
 226        for (pending = cb->mark_list; pending; pending = pending->next)
 227                pending->item->object.flags &= ~REACHABLE;
 228
 229        pending = cb->mark_list;
 230        while (pending) {
 231                struct commit_list *parent;
 232                struct commit *commit = pop_commit(&pending);
 233                if (commit->object.flags & REACHABLE)
 234                        continue;
 235                if (parse_commit(commit))
 236                        continue;
 237                commit->object.flags |= REACHABLE;
 238                if (commit->date < expire_limit) {
 239                        commit_list_insert(commit, &leftover);
 240                        continue;
 241                }
 242                commit->object.flags |= REACHABLE;
 243                parent = commit->parents;
 244                while (parent) {
 245                        commit = parent->item;
 246                        parent = parent->next;
 247                        if (commit->object.flags & REACHABLE)
 248                                continue;
 249                        commit_list_insert(commit, &pending);
 250                }
 251        }
 252        cb->mark_list = leftover;
 253}
 254
 255static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, struct object_id *oid)
 256{
 257        /*
 258         * We may or may not have the commit yet - if not, look it
 259         * up using the supplied sha1.
 260         */
 261        if (!commit) {
 262                if (is_null_oid(oid))
 263                        return 0;
 264
 265                commit = lookup_commit_reference_gently(oid, 1);
 266
 267                /* Not a commit -- keep it */
 268                if (!commit)
 269                        return 0;
 270        }
 271
 272        /* Reachable from the current ref?  Don't prune. */
 273        if (commit->object.flags & REACHABLE)
 274                return 0;
 275
 276        if (cb->mark_list && cb->mark_limit) {
 277                cb->mark_limit = 0; /* dig down to the root */
 278                mark_reachable(cb);
 279        }
 280
 281        return !(commit->object.flags & REACHABLE);
 282}
 283
 284/*
 285 * Return true iff the specified reflog entry should be expired.
 286 */
 287static int should_expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
 288                                    const char *email, timestamp_t timestamp, int tz,
 289                                    const char *message, void *cb_data)
 290{
 291        struct expire_reflog_policy_cb *cb = cb_data;
 292        struct commit *old, *new;
 293
 294        if (timestamp < cb->cmd.expire_total)
 295                return 1;
 296
 297        old = new = NULL;
 298        if (cb->cmd.stalefix &&
 299            (!keep_entry(&old, ooid) || !keep_entry(&new, noid)))
 300                return 1;
 301
 302        if (timestamp < cb->cmd.expire_unreachable) {
 303                if (cb->unreachable_expire_kind == UE_ALWAYS)
 304                        return 1;
 305                if (unreachable(cb, old, ooid) || unreachable(cb, new, noid))
 306                        return 1;
 307        }
 308
 309        if (cb->cmd.recno && --(cb->cmd.recno) == 0)
 310                return 1;
 311
 312        return 0;
 313}
 314
 315static int push_tip_to_list(const char *refname, const struct object_id *oid,
 316                            int flags, void *cb_data)
 317{
 318        struct commit_list **list = cb_data;
 319        struct commit *tip_commit;
 320        if (flags & REF_ISSYMREF)
 321                return 0;
 322        tip_commit = lookup_commit_reference_gently(oid, 1);
 323        if (!tip_commit)
 324                return 0;
 325        commit_list_insert(tip_commit, list);
 326        return 0;
 327}
 328
 329static void reflog_expiry_prepare(const char *refname,
 330                                  const struct object_id *oid,
 331                                  void *cb_data)
 332{
 333        struct expire_reflog_policy_cb *cb = cb_data;
 334
 335        if (!cb->cmd.expire_unreachable || !strcmp(refname, "HEAD")) {
 336                cb->tip_commit = NULL;
 337                cb->unreachable_expire_kind = UE_HEAD;
 338        } else {
 339                cb->tip_commit = lookup_commit_reference_gently(oid, 1);
 340                if (!cb->tip_commit)
 341                        cb->unreachable_expire_kind = UE_ALWAYS;
 342                else
 343                        cb->unreachable_expire_kind = UE_NORMAL;
 344        }
 345
 346        if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
 347                cb->unreachable_expire_kind = UE_ALWAYS;
 348
 349        cb->mark_list = NULL;
 350        cb->tips = NULL;
 351        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 352                if (cb->unreachable_expire_kind == UE_HEAD) {
 353                        struct commit_list *elem;
 354
 355                        for_each_ref(push_tip_to_list, &cb->tips);
 356                        for (elem = cb->tips; elem; elem = elem->next)
 357                                commit_list_insert(elem->item, &cb->mark_list);
 358                } else {
 359                        commit_list_insert(cb->tip_commit, &cb->mark_list);
 360                }
 361                cb->mark_limit = cb->cmd.expire_total;
 362                mark_reachable(cb);
 363        }
 364}
 365
 366static void reflog_expiry_cleanup(void *cb_data)
 367{
 368        struct expire_reflog_policy_cb *cb = cb_data;
 369
 370        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 371                if (cb->unreachable_expire_kind == UE_HEAD) {
 372                        struct commit_list *elem;
 373                        for (elem = cb->tips; elem; elem = elem->next)
 374                                clear_commit_marks(elem->item, REACHABLE);
 375                        free_commit_list(cb->tips);
 376                } else {
 377                        clear_commit_marks(cb->tip_commit, REACHABLE);
 378                }
 379        }
 380}
 381
 382static int collect_reflog(const char *ref, const struct object_id *oid, int unused, void *cb_data)
 383{
 384        struct collected_reflog *e;
 385        struct collect_reflog_cb *cb = cb_data;
 386
 387        FLEX_ALLOC_STR(e, reflog, ref);
 388        hashcpy(e->sha1, oid->hash);
 389        ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
 390        cb->e[cb->nr++] = e;
 391        return 0;
 392}
 393
 394static struct reflog_expire_cfg {
 395        struct reflog_expire_cfg *next;
 396        timestamp_t expire_total;
 397        timestamp_t expire_unreachable;
 398        char pattern[FLEX_ARRAY];
 399} *reflog_expire_cfg, **reflog_expire_cfg_tail;
 400
 401static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
 402{
 403        struct reflog_expire_cfg *ent;
 404
 405        if (!reflog_expire_cfg_tail)
 406                reflog_expire_cfg_tail = &reflog_expire_cfg;
 407
 408        for (ent = reflog_expire_cfg; ent; ent = ent->next)
 409                if (!strncmp(ent->pattern, pattern, len) &&
 410                    ent->pattern[len] == '\0')
 411                        return ent;
 412
 413        FLEX_ALLOC_MEM(ent, pattern, pattern, len);
 414        *reflog_expire_cfg_tail = ent;
 415        reflog_expire_cfg_tail = &(ent->next);
 416        return ent;
 417}
 418
 419static int parse_expire_cfg_value(const char *var, const char *value, timestamp_t *expire)
 420{
 421        if (!value)
 422                return config_error_nonbool(var);
 423        if (parse_expiry_date(value, expire))
 424                return error(_("'%s' for '%s' is not a valid timestamp"),
 425                             value, var);
 426        return 0;
 427}
 428
 429/* expiry timer slot */
 430#define EXPIRE_TOTAL   01
 431#define EXPIRE_UNREACH 02
 432
 433static int reflog_expire_config(const char *var, const char *value, void *cb)
 434{
 435        const char *pattern, *key;
 436        int pattern_len;
 437        timestamp_t expire;
 438        int slot;
 439        struct reflog_expire_cfg *ent;
 440
 441        if (parse_config_key(var, "gc", &pattern, &pattern_len, &key) < 0)
 442                return git_default_config(var, value, cb);
 443
 444        if (!strcmp(key, "reflogexpire")) {
 445                slot = EXPIRE_TOTAL;
 446                if (parse_expire_cfg_value(var, value, &expire))
 447                        return -1;
 448        } else if (!strcmp(key, "reflogexpireunreachable")) {
 449                slot = EXPIRE_UNREACH;
 450                if (parse_expire_cfg_value(var, value, &expire))
 451                        return -1;
 452        } else
 453                return git_default_config(var, value, cb);
 454
 455        if (!pattern) {
 456                switch (slot) {
 457                case EXPIRE_TOTAL:
 458                        default_reflog_expire = expire;
 459                        break;
 460                case EXPIRE_UNREACH:
 461                        default_reflog_expire_unreachable = expire;
 462                        break;
 463                }
 464                return 0;
 465        }
 466
 467        ent = find_cfg_ent(pattern, pattern_len);
 468        if (!ent)
 469                return -1;
 470        switch (slot) {
 471        case EXPIRE_TOTAL:
 472                ent->expire_total = expire;
 473                break;
 474        case EXPIRE_UNREACH:
 475                ent->expire_unreachable = expire;
 476                break;
 477        }
 478        return 0;
 479}
 480
 481static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
 482{
 483        struct reflog_expire_cfg *ent;
 484
 485        if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
 486                return; /* both given explicitly -- nothing to tweak */
 487
 488        for (ent = reflog_expire_cfg; ent; ent = ent->next) {
 489                if (!wildmatch(ent->pattern, ref, 0)) {
 490                        if (!(slot & EXPIRE_TOTAL))
 491                                cb->expire_total = ent->expire_total;
 492                        if (!(slot & EXPIRE_UNREACH))
 493                                cb->expire_unreachable = ent->expire_unreachable;
 494                        return;
 495                }
 496        }
 497
 498        /*
 499         * If unconfigured, make stash never expire
 500         */
 501        if (!strcmp(ref, "refs/stash")) {
 502                if (!(slot & EXPIRE_TOTAL))
 503                        cb->expire_total = 0;
 504                if (!(slot & EXPIRE_UNREACH))
 505                        cb->expire_unreachable = 0;
 506                return;
 507        }
 508
 509        /* Nothing matched -- use the default value */
 510        if (!(slot & EXPIRE_TOTAL))
 511                cb->expire_total = default_reflog_expire;
 512        if (!(slot & EXPIRE_UNREACH))
 513                cb->expire_unreachable = default_reflog_expire_unreachable;
 514}
 515
 516static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 517{
 518        struct expire_reflog_policy_cb cb;
 519        timestamp_t now = time(NULL);
 520        int i, status, do_all;
 521        int explicit_expiry = 0;
 522        unsigned int flags = 0;
 523
 524        default_reflog_expire_unreachable = now - 30 * 24 * 3600;
 525        default_reflog_expire = now - 90 * 24 * 3600;
 526        git_config(reflog_expire_config, NULL);
 527
 528        save_commit_buffer = 0;
 529        do_all = status = 0;
 530        memset(&cb, 0, sizeof(cb));
 531
 532        cb.cmd.expire_total = default_reflog_expire;
 533        cb.cmd.expire_unreachable = default_reflog_expire_unreachable;
 534
 535        for (i = 1; i < argc; i++) {
 536                const char *arg = argv[i];
 537                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 538                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 539                else if (starts_with(arg, "--expire=")) {
 540                        if (parse_expiry_date(arg + 9, &cb.cmd.expire_total))
 541                                die(_("'%s' is not a valid timestamp"), arg);
 542                        explicit_expiry |= EXPIRE_TOTAL;
 543                }
 544                else if (starts_with(arg, "--expire-unreachable=")) {
 545                        if (parse_expiry_date(arg + 21, &cb.cmd.expire_unreachable))
 546                                die(_("'%s' is not a valid timestamp"), arg);
 547                        explicit_expiry |= EXPIRE_UNREACH;
 548                }
 549                else if (!strcmp(arg, "--stale-fix"))
 550                        cb.cmd.stalefix = 1;
 551                else if (!strcmp(arg, "--rewrite"))
 552                        flags |= EXPIRE_REFLOGS_REWRITE;
 553                else if (!strcmp(arg, "--updateref"))
 554                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 555                else if (!strcmp(arg, "--all"))
 556                        do_all = 1;
 557                else if (!strcmp(arg, "--verbose"))
 558                        flags |= EXPIRE_REFLOGS_VERBOSE;
 559                else if (!strcmp(arg, "--")) {
 560                        i++;
 561                        break;
 562                }
 563                else if (arg[0] == '-')
 564                        usage(reflog_expire_usage);
 565                else
 566                        break;
 567        }
 568
 569        /*
 570         * We can trust the commits and objects reachable from refs
 571         * even in older repository.  We cannot trust what's reachable
 572         * from reflog if the repository was pruned with older git.
 573         */
 574        if (cb.cmd.stalefix) {
 575                init_revisions(&cb.cmd.revs, prefix);
 576                if (flags & EXPIRE_REFLOGS_VERBOSE)
 577                        printf("Marking reachable objects...");
 578                mark_reachable_objects(&cb.cmd.revs, 0, 0, NULL);
 579                if (flags & EXPIRE_REFLOGS_VERBOSE)
 580                        putchar('\n');
 581        }
 582
 583        if (do_all) {
 584                struct collect_reflog_cb collected;
 585                int i;
 586
 587                memset(&collected, 0, sizeof(collected));
 588                for_each_reflog(collect_reflog, &collected);
 589                for (i = 0; i < collected.nr; i++) {
 590                        struct collected_reflog *e = collected.e[i];
 591                        set_reflog_expiry_param(&cb.cmd, explicit_expiry, e->reflog);
 592                        status |= reflog_expire(e->reflog, e->sha1, flags,
 593                                                reflog_expiry_prepare,
 594                                                should_expire_reflog_ent,
 595                                                reflog_expiry_cleanup,
 596                                                &cb);
 597                        free(e);
 598                }
 599                free(collected.e);
 600        }
 601
 602        for (; i < argc; i++) {
 603                char *ref;
 604                unsigned char sha1[20];
 605                if (!dwim_log(argv[i], strlen(argv[i]), sha1, &ref)) {
 606                        status |= error("%s points nowhere!", argv[i]);
 607                        continue;
 608                }
 609                set_reflog_expiry_param(&cb.cmd, explicit_expiry, ref);
 610                status |= reflog_expire(ref, sha1, flags,
 611                                        reflog_expiry_prepare,
 612                                        should_expire_reflog_ent,
 613                                        reflog_expiry_cleanup,
 614                                        &cb);
 615        }
 616        return status;
 617}
 618
 619static int count_reflog_ent(struct object_id *ooid, struct object_id *noid,
 620                const char *email, timestamp_t timestamp, int tz,
 621                const char *message, void *cb_data)
 622{
 623        struct expire_reflog_policy_cb *cb = cb_data;
 624        if (!cb->cmd.expire_total || timestamp < cb->cmd.expire_total)
 625                cb->cmd.recno++;
 626        return 0;
 627}
 628
 629static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 630{
 631        struct expire_reflog_policy_cb cb;
 632        int i, status = 0;
 633        unsigned int flags = 0;
 634
 635        memset(&cb, 0, sizeof(cb));
 636
 637        for (i = 1; i < argc; i++) {
 638                const char *arg = argv[i];
 639                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 640                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 641                else if (!strcmp(arg, "--rewrite"))
 642                        flags |= EXPIRE_REFLOGS_REWRITE;
 643                else if (!strcmp(arg, "--updateref"))
 644                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 645                else if (!strcmp(arg, "--verbose"))
 646                        flags |= EXPIRE_REFLOGS_VERBOSE;
 647                else if (!strcmp(arg, "--")) {
 648                        i++;
 649                        break;
 650                }
 651                else if (arg[0] == '-')
 652                        usage(reflog_delete_usage);
 653                else
 654                        break;
 655        }
 656
 657        if (argc - i < 1)
 658                return error("Nothing to delete?");
 659
 660        for ( ; i < argc; i++) {
 661                const char *spec = strstr(argv[i], "@{");
 662                unsigned char sha1[20];
 663                char *ep, *ref;
 664                int recno;
 665
 666                if (!spec) {
 667                        status |= error("Not a reflog: %s", argv[i]);
 668                        continue;
 669                }
 670
 671                if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
 672                        status |= error("no reflog for '%s'", argv[i]);
 673                        continue;
 674                }
 675
 676                recno = strtoul(spec + 2, &ep, 10);
 677                if (*ep == '}') {
 678                        cb.cmd.recno = -recno;
 679                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 680                } else {
 681                        cb.cmd.expire_total = approxidate(spec + 2);
 682                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 683                        cb.cmd.expire_total = 0;
 684                }
 685
 686                status |= reflog_expire(ref, sha1, flags,
 687                                        reflog_expiry_prepare,
 688                                        should_expire_reflog_ent,
 689                                        reflog_expiry_cleanup,
 690                                        &cb);
 691                free(ref);
 692        }
 693        return status;
 694}
 695
 696static int cmd_reflog_exists(int argc, const char **argv, const char *prefix)
 697{
 698        int i, start = 0;
 699
 700        for (i = 1; i < argc; i++) {
 701                const char *arg = argv[i];
 702                if (!strcmp(arg, "--")) {
 703                        i++;
 704                        break;
 705                }
 706                else if (arg[0] == '-')
 707                        usage(reflog_exists_usage);
 708                else
 709                        break;
 710        }
 711
 712        start = i;
 713
 714        if (argc - start != 1)
 715                usage(reflog_exists_usage);
 716
 717        if (check_refname_format(argv[start], REFNAME_ALLOW_ONELEVEL))
 718                die("invalid ref format: %s", argv[start]);
 719        return !reflog_exists(argv[start]);
 720}
 721
 722/*
 723 * main "reflog"
 724 */
 725
 726static const char reflog_usage[] =
 727"git reflog [ show | expire | delete | exists ]";
 728
 729int cmd_reflog(int argc, const char **argv, const char *prefix)
 730{
 731        if (argc > 1 && !strcmp(argv[1], "-h"))
 732                usage(reflog_usage);
 733
 734        /* With no command, we default to showing it. */
 735        if (argc < 2 || *argv[1] == '-')
 736                return cmd_log_reflog(argc, argv, prefix);
 737
 738        if (!strcmp(argv[1], "show"))
 739                return cmd_log_reflog(argc - 1, argv + 1, prefix);
 740
 741        if (!strcmp(argv[1], "expire"))
 742                return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 743
 744        if (!strcmp(argv[1], "delete"))
 745                return cmd_reflog_delete(argc - 1, argv + 1, prefix);
 746
 747        if (!strcmp(argv[1], "exists"))
 748                return cmd_reflog_exists(argc - 1, argv + 1, prefix);
 749
 750        return cmd_log_reflog(argc, argv, prefix);
 751}