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#include "worktree.h"
  14
  15/* NEEDSWORK: switch to using parse_options */
  16static const char reflog_expire_usage[] =
  17"git reflog expire [--expire=<time>] [--expire-unreachable=<time>] [--rewrite] [--updateref] [--stale-fix] [--dry-run | -n] [--verbose] [--all] <refs>...";
  18static const char reflog_delete_usage[] =
  19"git reflog delete [--rewrite] [--updateref] [--dry-run | -n] [--verbose] <refs>...";
  20static const char reflog_exists_usage[] =
  21"git reflog exists <ref>";
  22
  23static timestamp_t default_reflog_expire;
  24static timestamp_t default_reflog_expire_unreachable;
  25
  26struct cmd_reflog_expire_cb {
  27        struct rev_info revs;
  28        int stalefix;
  29        timestamp_t expire_total;
  30        timestamp_t expire_unreachable;
  31        int recno;
  32};
  33
  34struct expire_reflog_policy_cb {
  35        enum {
  36                UE_NORMAL,
  37                UE_ALWAYS,
  38                UE_HEAD
  39        } unreachable_expire_kind;
  40        struct commit_list *mark_list;
  41        unsigned long mark_limit;
  42        struct cmd_reflog_expire_cb cmd;
  43        struct commit *tip_commit;
  44        struct commit_list *tips;
  45};
  46
  47struct collected_reflog {
  48        struct object_id oid;
  49        char reflog[FLEX_ARRAY];
  50};
  51
  52struct collect_reflog_cb {
  53        struct collected_reflog **e;
  54        int alloc;
  55        int nr;
  56        struct worktree *wt;
  57};
  58
  59/* Remember to update object flag allocation in object.h */
  60#define INCOMPLETE      (1u<<10)
  61#define STUDYING        (1u<<11)
  62#define REACHABLE       (1u<<12)
  63
  64static int tree_is_complete(const struct object_id *oid)
  65{
  66        struct tree_desc desc;
  67        struct name_entry entry;
  68        int complete;
  69        struct tree *tree;
  70
  71        tree = lookup_tree(the_repository, oid);
  72        if (!tree)
  73                return 0;
  74        if (tree->object.flags & SEEN)
  75                return 1;
  76        if (tree->object.flags & INCOMPLETE)
  77                return 0;
  78
  79        if (!tree->buffer) {
  80                enum object_type type;
  81                unsigned long size;
  82                void *data = read_object_file(oid, &type, &size);
  83                if (!data) {
  84                        tree->object.flags |= INCOMPLETE;
  85                        return 0;
  86                }
  87                tree->buffer = data;
  88                tree->size = size;
  89        }
  90        init_tree_desc(&desc, tree->buffer, tree->size);
  91        complete = 1;
  92        while (tree_entry(&desc, &entry)) {
  93                if (!has_sha1_file(entry.oid->hash) ||
  94                    (S_ISDIR(entry.mode) && !tree_is_complete(entry.oid))) {
  95                        tree->object.flags |= INCOMPLETE;
  96                        complete = 0;
  97                }
  98        }
  99        free_tree_buffer(tree);
 100
 101        if (complete)
 102                tree->object.flags |= SEEN;
 103        return complete;
 104}
 105
 106static int commit_is_complete(struct commit *commit)
 107{
 108        struct object_array study;
 109        struct object_array found;
 110        int is_incomplete = 0;
 111        int i;
 112
 113        /* early return */
 114        if (commit->object.flags & SEEN)
 115                return 1;
 116        if (commit->object.flags & INCOMPLETE)
 117                return 0;
 118        /*
 119         * Find all commits that are reachable and are not marked as
 120         * SEEN.  Then make sure the trees and blobs contained are
 121         * complete.  After that, mark these commits also as SEEN.
 122         * If some of the objects that are needed to complete this
 123         * commit are missing, mark this commit as INCOMPLETE.
 124         */
 125        memset(&study, 0, sizeof(study));
 126        memset(&found, 0, sizeof(found));
 127        add_object_array(&commit->object, NULL, &study);
 128        add_object_array(&commit->object, NULL, &found);
 129        commit->object.flags |= STUDYING;
 130        while (study.nr) {
 131                struct commit *c;
 132                struct commit_list *parent;
 133
 134                c = (struct commit *)object_array_pop(&study);
 135                if (!c->object.parsed && !parse_object(the_repository, &c->object.oid))
 136                        c->object.flags |= INCOMPLETE;
 137
 138                if (c->object.flags & INCOMPLETE) {
 139                        is_incomplete = 1;
 140                        break;
 141                }
 142                else if (c->object.flags & SEEN)
 143                        continue;
 144                for (parent = c->parents; parent; parent = parent->next) {
 145                        struct commit *p = parent->item;
 146                        if (p->object.flags & STUDYING)
 147                                continue;
 148                        p->object.flags |= STUDYING;
 149                        add_object_array(&p->object, NULL, &study);
 150                        add_object_array(&p->object, NULL, &found);
 151                }
 152        }
 153        if (!is_incomplete) {
 154                /*
 155                 * make sure all commits in "found" array have all the
 156                 * necessary objects.
 157                 */
 158                for (i = 0; i < found.nr; i++) {
 159                        struct commit *c =
 160                                (struct commit *)found.objects[i].item;
 161                        if (!tree_is_complete(get_commit_tree_oid(c))) {
 162                                is_incomplete = 1;
 163                                c->object.flags |= INCOMPLETE;
 164                        }
 165                }
 166                if (!is_incomplete) {
 167                        /* mark all found commits as complete, iow SEEN */
 168                        for (i = 0; i < found.nr; i++)
 169                                found.objects[i].item->flags |= SEEN;
 170                }
 171        }
 172        /* clear flags from the objects we traversed */
 173        for (i = 0; i < found.nr; i++)
 174                found.objects[i].item->flags &= ~STUDYING;
 175        if (is_incomplete)
 176                commit->object.flags |= INCOMPLETE;
 177        else {
 178                /*
 179                 * If we come here, we have (1) traversed the ancestry chain
 180                 * from the "commit" until we reach SEEN commits (which are
 181                 * known to be complete), and (2) made sure that the commits
 182                 * encountered during the above traversal refer to trees that
 183                 * are complete.  Which means that we know *all* the commits
 184                 * we have seen during this process are complete.
 185                 */
 186                for (i = 0; i < found.nr; i++)
 187                        found.objects[i].item->flags |= SEEN;
 188        }
 189        /* free object arrays */
 190        object_array_clear(&study);
 191        object_array_clear(&found);
 192        return !is_incomplete;
 193}
 194
 195static int keep_entry(struct commit **it, struct object_id *oid)
 196{
 197        struct commit *commit;
 198
 199        if (is_null_oid(oid))
 200                return 1;
 201        commit = lookup_commit_reference_gently(the_repository, oid, 1);
 202        if (!commit)
 203                return 0;
 204
 205        /*
 206         * Make sure everything in this commit exists.
 207         *
 208         * We have walked all the objects reachable from the refs
 209         * and cache earlier.  The commits reachable by this commit
 210         * must meet SEEN commits -- and then we should mark them as
 211         * SEEN as well.
 212         */
 213        if (!commit_is_complete(commit))
 214                return 0;
 215        *it = commit;
 216        return 1;
 217}
 218
 219/*
 220 * Starting from commits in the cb->mark_list, mark commits that are
 221 * reachable from them.  Stop the traversal at commits older than
 222 * the expire_limit and queue them back, so that the caller can call
 223 * us again to restart the traversal with longer expire_limit.
 224 */
 225static void mark_reachable(struct expire_reflog_policy_cb *cb)
 226{
 227        struct commit_list *pending;
 228        timestamp_t expire_limit = cb->mark_limit;
 229        struct commit_list *leftover = NULL;
 230
 231        for (pending = cb->mark_list; pending; pending = pending->next)
 232                pending->item->object.flags &= ~REACHABLE;
 233
 234        pending = cb->mark_list;
 235        while (pending) {
 236                struct commit_list *parent;
 237                struct commit *commit = pop_commit(&pending);
 238                if (commit->object.flags & REACHABLE)
 239                        continue;
 240                if (parse_commit(commit))
 241                        continue;
 242                commit->object.flags |= REACHABLE;
 243                if (commit->date < expire_limit) {
 244                        commit_list_insert(commit, &leftover);
 245                        continue;
 246                }
 247                commit->object.flags |= REACHABLE;
 248                parent = commit->parents;
 249                while (parent) {
 250                        commit = parent->item;
 251                        parent = parent->next;
 252                        if (commit->object.flags & REACHABLE)
 253                                continue;
 254                        commit_list_insert(commit, &pending);
 255                }
 256        }
 257        cb->mark_list = leftover;
 258}
 259
 260static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, struct object_id *oid)
 261{
 262        /*
 263         * We may or may not have the commit yet - if not, look it
 264         * up using the supplied sha1.
 265         */
 266        if (!commit) {
 267                if (is_null_oid(oid))
 268                        return 0;
 269
 270                commit = lookup_commit_reference_gently(the_repository, oid,
 271                                                        1);
 272
 273                /* Not a commit -- keep it */
 274                if (!commit)
 275                        return 0;
 276        }
 277
 278        /* Reachable from the current ref?  Don't prune. */
 279        if (commit->object.flags & REACHABLE)
 280                return 0;
 281
 282        if (cb->mark_list && cb->mark_limit) {
 283                cb->mark_limit = 0; /* dig down to the root */
 284                mark_reachable(cb);
 285        }
 286
 287        return !(commit->object.flags & REACHABLE);
 288}
 289
 290/*
 291 * Return true iff the specified reflog entry should be expired.
 292 */
 293static int should_expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
 294                                    const char *email, timestamp_t timestamp, int tz,
 295                                    const char *message, void *cb_data)
 296{
 297        struct expire_reflog_policy_cb *cb = cb_data;
 298        struct commit *old_commit, *new_commit;
 299
 300        if (timestamp < cb->cmd.expire_total)
 301                return 1;
 302
 303        old_commit = new_commit = NULL;
 304        if (cb->cmd.stalefix &&
 305            (!keep_entry(&old_commit, ooid) || !keep_entry(&new_commit, noid)))
 306                return 1;
 307
 308        if (timestamp < cb->cmd.expire_unreachable) {
 309                if (cb->unreachable_expire_kind == UE_ALWAYS)
 310                        return 1;
 311                if (unreachable(cb, old_commit, ooid) || unreachable(cb, new_commit, noid))
 312                        return 1;
 313        }
 314
 315        if (cb->cmd.recno && --(cb->cmd.recno) == 0)
 316                return 1;
 317
 318        return 0;
 319}
 320
 321static int push_tip_to_list(const char *refname, const struct object_id *oid,
 322                            int flags, void *cb_data)
 323{
 324        struct commit_list **list = cb_data;
 325        struct commit *tip_commit;
 326        if (flags & REF_ISSYMREF)
 327                return 0;
 328        tip_commit = lookup_commit_reference_gently(the_repository, oid, 1);
 329        if (!tip_commit)
 330                return 0;
 331        commit_list_insert(tip_commit, list);
 332        return 0;
 333}
 334
 335static int is_head(const char *refname)
 336{
 337        switch (ref_type(refname)) {
 338        case REF_TYPE_OTHER_PSEUDOREF:
 339        case REF_TYPE_MAIN_PSEUDOREF:
 340                if (parse_worktree_ref(refname, NULL, NULL, &refname))
 341                        BUG("not a worktree ref: %s", refname);
 342                break;
 343        default:
 344                break;
 345        }
 346        return !strcmp(refname, "HEAD");
 347}
 348
 349static void reflog_expiry_prepare(const char *refname,
 350                                  const struct object_id *oid,
 351                                  void *cb_data)
 352{
 353        struct expire_reflog_policy_cb *cb = cb_data;
 354
 355        if (!cb->cmd.expire_unreachable || is_head(refname)) {
 356                cb->tip_commit = NULL;
 357                cb->unreachable_expire_kind = UE_HEAD;
 358        } else {
 359                cb->tip_commit = lookup_commit_reference_gently(the_repository,
 360                                                                oid, 1);
 361                if (!cb->tip_commit)
 362                        cb->unreachable_expire_kind = UE_ALWAYS;
 363                else
 364                        cb->unreachable_expire_kind = UE_NORMAL;
 365        }
 366
 367        if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
 368                cb->unreachable_expire_kind = UE_ALWAYS;
 369
 370        cb->mark_list = NULL;
 371        cb->tips = NULL;
 372        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 373                if (cb->unreachable_expire_kind == UE_HEAD) {
 374                        struct commit_list *elem;
 375
 376                        for_each_ref(push_tip_to_list, &cb->tips);
 377                        for (elem = cb->tips; elem; elem = elem->next)
 378                                commit_list_insert(elem->item, &cb->mark_list);
 379                } else {
 380                        commit_list_insert(cb->tip_commit, &cb->mark_list);
 381                }
 382                cb->mark_limit = cb->cmd.expire_total;
 383                mark_reachable(cb);
 384        }
 385}
 386
 387static void reflog_expiry_cleanup(void *cb_data)
 388{
 389        struct expire_reflog_policy_cb *cb = cb_data;
 390
 391        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 392                if (cb->unreachable_expire_kind == UE_HEAD) {
 393                        struct commit_list *elem;
 394                        for (elem = cb->tips; elem; elem = elem->next)
 395                                clear_commit_marks(elem->item, REACHABLE);
 396                        free_commit_list(cb->tips);
 397                } else {
 398                        clear_commit_marks(cb->tip_commit, REACHABLE);
 399                }
 400        }
 401}
 402
 403static int collect_reflog(const char *ref, const struct object_id *oid, int unused, void *cb_data)
 404{
 405        struct collected_reflog *e;
 406        struct collect_reflog_cb *cb = cb_data;
 407        struct strbuf newref = STRBUF_INIT;
 408
 409        /*
 410         * Avoid collecting the same shared ref multiple times because
 411         * they are available via all worktrees.
 412         */
 413        if (!cb->wt->is_current && ref_type(ref) == REF_TYPE_NORMAL)
 414                return 0;
 415
 416        strbuf_worktree_ref(cb->wt, &newref, ref);
 417        FLEX_ALLOC_STR(e, reflog, newref.buf);
 418        strbuf_release(&newref);
 419
 420        oidcpy(&e->oid, oid);
 421        ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
 422        cb->e[cb->nr++] = e;
 423        return 0;
 424}
 425
 426static struct reflog_expire_cfg {
 427        struct reflog_expire_cfg *next;
 428        timestamp_t expire_total;
 429        timestamp_t expire_unreachable;
 430        char pattern[FLEX_ARRAY];
 431} *reflog_expire_cfg, **reflog_expire_cfg_tail;
 432
 433static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
 434{
 435        struct reflog_expire_cfg *ent;
 436
 437        if (!reflog_expire_cfg_tail)
 438                reflog_expire_cfg_tail = &reflog_expire_cfg;
 439
 440        for (ent = reflog_expire_cfg; ent; ent = ent->next)
 441                if (!strncmp(ent->pattern, pattern, len) &&
 442                    ent->pattern[len] == '\0')
 443                        return ent;
 444
 445        FLEX_ALLOC_MEM(ent, pattern, pattern, len);
 446        *reflog_expire_cfg_tail = ent;
 447        reflog_expire_cfg_tail = &(ent->next);
 448        return ent;
 449}
 450
 451/* expiry timer slot */
 452#define EXPIRE_TOTAL   01
 453#define EXPIRE_UNREACH 02
 454
 455static int reflog_expire_config(const char *var, const char *value, void *cb)
 456{
 457        const char *pattern, *key;
 458        int pattern_len;
 459        timestamp_t expire;
 460        int slot;
 461        struct reflog_expire_cfg *ent;
 462
 463        if (parse_config_key(var, "gc", &pattern, &pattern_len, &key) < 0)
 464                return git_default_config(var, value, cb);
 465
 466        if (!strcmp(key, "reflogexpire")) {
 467                slot = EXPIRE_TOTAL;
 468                if (git_config_expiry_date(&expire, var, value))
 469                        return -1;
 470        } else if (!strcmp(key, "reflogexpireunreachable")) {
 471                slot = EXPIRE_UNREACH;
 472                if (git_config_expiry_date(&expire, var, value))
 473                        return -1;
 474        } else
 475                return git_default_config(var, value, cb);
 476
 477        if (!pattern) {
 478                switch (slot) {
 479                case EXPIRE_TOTAL:
 480                        default_reflog_expire = expire;
 481                        break;
 482                case EXPIRE_UNREACH:
 483                        default_reflog_expire_unreachable = expire;
 484                        break;
 485                }
 486                return 0;
 487        }
 488
 489        ent = find_cfg_ent(pattern, pattern_len);
 490        if (!ent)
 491                return -1;
 492        switch (slot) {
 493        case EXPIRE_TOTAL:
 494                ent->expire_total = expire;
 495                break;
 496        case EXPIRE_UNREACH:
 497                ent->expire_unreachable = expire;
 498                break;
 499        }
 500        return 0;
 501}
 502
 503static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
 504{
 505        struct reflog_expire_cfg *ent;
 506
 507        if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
 508                return; /* both given explicitly -- nothing to tweak */
 509
 510        for (ent = reflog_expire_cfg; ent; ent = ent->next) {
 511                if (!wildmatch(ent->pattern, ref, 0)) {
 512                        if (!(slot & EXPIRE_TOTAL))
 513                                cb->expire_total = ent->expire_total;
 514                        if (!(slot & EXPIRE_UNREACH))
 515                                cb->expire_unreachable = ent->expire_unreachable;
 516                        return;
 517                }
 518        }
 519
 520        /*
 521         * If unconfigured, make stash never expire
 522         */
 523        if (!strcmp(ref, "refs/stash")) {
 524                if (!(slot & EXPIRE_TOTAL))
 525                        cb->expire_total = 0;
 526                if (!(slot & EXPIRE_UNREACH))
 527                        cb->expire_unreachable = 0;
 528                return;
 529        }
 530
 531        /* Nothing matched -- use the default value */
 532        if (!(slot & EXPIRE_TOTAL))
 533                cb->expire_total = default_reflog_expire;
 534        if (!(slot & EXPIRE_UNREACH))
 535                cb->expire_unreachable = default_reflog_expire_unreachable;
 536}
 537
 538static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 539{
 540        struct expire_reflog_policy_cb cb;
 541        timestamp_t now = time(NULL);
 542        int i, status, do_all, all_worktrees = 1;
 543        int explicit_expiry = 0;
 544        unsigned int flags = 0;
 545
 546        default_reflog_expire_unreachable = now - 30 * 24 * 3600;
 547        default_reflog_expire = now - 90 * 24 * 3600;
 548        git_config(reflog_expire_config, NULL);
 549
 550        save_commit_buffer = 0;
 551        do_all = status = 0;
 552        memset(&cb, 0, sizeof(cb));
 553
 554        cb.cmd.expire_total = default_reflog_expire;
 555        cb.cmd.expire_unreachable = default_reflog_expire_unreachable;
 556
 557        for (i = 1; i < argc; i++) {
 558                const char *arg = argv[i];
 559                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 560                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 561                else if (starts_with(arg, "--expire=")) {
 562                        if (parse_expiry_date(arg + 9, &cb.cmd.expire_total))
 563                                die(_("'%s' is not a valid timestamp"), arg);
 564                        explicit_expiry |= EXPIRE_TOTAL;
 565                }
 566                else if (starts_with(arg, "--expire-unreachable=")) {
 567                        if (parse_expiry_date(arg + 21, &cb.cmd.expire_unreachable))
 568                                die(_("'%s' is not a valid timestamp"), arg);
 569                        explicit_expiry |= EXPIRE_UNREACH;
 570                }
 571                else if (!strcmp(arg, "--stale-fix"))
 572                        cb.cmd.stalefix = 1;
 573                else if (!strcmp(arg, "--rewrite"))
 574                        flags |= EXPIRE_REFLOGS_REWRITE;
 575                else if (!strcmp(arg, "--updateref"))
 576                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 577                else if (!strcmp(arg, "--all"))
 578                        do_all = 1;
 579                else if (!strcmp(arg, "--single-worktree"))
 580                        all_worktrees = 0;
 581                else if (!strcmp(arg, "--verbose"))
 582                        flags |= EXPIRE_REFLOGS_VERBOSE;
 583                else if (!strcmp(arg, "--")) {
 584                        i++;
 585                        break;
 586                }
 587                else if (arg[0] == '-')
 588                        usage(reflog_expire_usage);
 589                else
 590                        break;
 591        }
 592
 593        /*
 594         * We can trust the commits and objects reachable from refs
 595         * even in older repository.  We cannot trust what's reachable
 596         * from reflog if the repository was pruned with older git.
 597         */
 598        if (cb.cmd.stalefix) {
 599                repo_init_revisions(the_repository, &cb.cmd.revs, prefix);
 600                if (flags & EXPIRE_REFLOGS_VERBOSE)
 601                        printf("Marking reachable objects...");
 602                mark_reachable_objects(&cb.cmd.revs, 0, 0, NULL);
 603                if (flags & EXPIRE_REFLOGS_VERBOSE)
 604                        putchar('\n');
 605        }
 606
 607        if (do_all) {
 608                struct collect_reflog_cb collected;
 609                struct worktree **worktrees, **p;
 610                int i;
 611
 612                memset(&collected, 0, sizeof(collected));
 613                worktrees = get_worktrees(0);
 614                for (p = worktrees; *p; p++) {
 615                        if (!all_worktrees && !(*p)->is_current)
 616                                continue;
 617                        collected.wt = *p;
 618                        refs_for_each_reflog(get_worktree_ref_store(*p),
 619                                             collect_reflog, &collected);
 620                }
 621                free_worktrees(worktrees);
 622                for (i = 0; i < collected.nr; i++) {
 623                        struct collected_reflog *e = collected.e[i];
 624                        set_reflog_expiry_param(&cb.cmd, explicit_expiry, e->reflog);
 625                        status |= reflog_expire(e->reflog, &e->oid, flags,
 626                                                reflog_expiry_prepare,
 627                                                should_expire_reflog_ent,
 628                                                reflog_expiry_cleanup,
 629                                                &cb);
 630                        free(e);
 631                }
 632                free(collected.e);
 633        }
 634
 635        for (; i < argc; i++) {
 636                char *ref;
 637                struct object_id oid;
 638                if (!dwim_log(argv[i], strlen(argv[i]), &oid, &ref)) {
 639                        status |= error("%s points nowhere!", argv[i]);
 640                        continue;
 641                }
 642                set_reflog_expiry_param(&cb.cmd, explicit_expiry, ref);
 643                status |= reflog_expire(ref, &oid, flags,
 644                                        reflog_expiry_prepare,
 645                                        should_expire_reflog_ent,
 646                                        reflog_expiry_cleanup,
 647                                        &cb);
 648        }
 649        return status;
 650}
 651
 652static int count_reflog_ent(struct object_id *ooid, struct object_id *noid,
 653                const char *email, timestamp_t timestamp, int tz,
 654                const char *message, void *cb_data)
 655{
 656        struct expire_reflog_policy_cb *cb = cb_data;
 657        if (!cb->cmd.expire_total || timestamp < cb->cmd.expire_total)
 658                cb->cmd.recno++;
 659        return 0;
 660}
 661
 662static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 663{
 664        struct expire_reflog_policy_cb cb;
 665        int i, status = 0;
 666        unsigned int flags = 0;
 667
 668        memset(&cb, 0, sizeof(cb));
 669
 670        for (i = 1; i < argc; i++) {
 671                const char *arg = argv[i];
 672                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 673                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 674                else if (!strcmp(arg, "--rewrite"))
 675                        flags |= EXPIRE_REFLOGS_REWRITE;
 676                else if (!strcmp(arg, "--updateref"))
 677                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 678                else if (!strcmp(arg, "--verbose"))
 679                        flags |= EXPIRE_REFLOGS_VERBOSE;
 680                else if (!strcmp(arg, "--")) {
 681                        i++;
 682                        break;
 683                }
 684                else if (arg[0] == '-')
 685                        usage(reflog_delete_usage);
 686                else
 687                        break;
 688        }
 689
 690        if (argc - i < 1)
 691                return error("Nothing to delete?");
 692
 693        for ( ; i < argc; i++) {
 694                const char *spec = strstr(argv[i], "@{");
 695                struct object_id oid;
 696                char *ep, *ref;
 697                int recno;
 698
 699                if (!spec) {
 700                        status |= error("Not a reflog: %s", argv[i]);
 701                        continue;
 702                }
 703
 704                if (!dwim_log(argv[i], spec - argv[i], &oid, &ref)) {
 705                        status |= error("no reflog for '%s'", argv[i]);
 706                        continue;
 707                }
 708
 709                recno = strtoul(spec + 2, &ep, 10);
 710                if (*ep == '}') {
 711                        cb.cmd.recno = -recno;
 712                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 713                } else {
 714                        cb.cmd.expire_total = approxidate(spec + 2);
 715                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 716                        cb.cmd.expire_total = 0;
 717                }
 718
 719                status |= reflog_expire(ref, &oid, flags,
 720                                        reflog_expiry_prepare,
 721                                        should_expire_reflog_ent,
 722                                        reflog_expiry_cleanup,
 723                                        &cb);
 724                free(ref);
 725        }
 726        return status;
 727}
 728
 729static int cmd_reflog_exists(int argc, const char **argv, const char *prefix)
 730{
 731        int i, start = 0;
 732
 733        for (i = 1; i < argc; i++) {
 734                const char *arg = argv[i];
 735                if (!strcmp(arg, "--")) {
 736                        i++;
 737                        break;
 738                }
 739                else if (arg[0] == '-')
 740                        usage(reflog_exists_usage);
 741                else
 742                        break;
 743        }
 744
 745        start = i;
 746
 747        if (argc - start != 1)
 748                usage(reflog_exists_usage);
 749
 750        if (check_refname_format(argv[start], REFNAME_ALLOW_ONELEVEL))
 751                die("invalid ref format: %s", argv[start]);
 752        return !reflog_exists(argv[start]);
 753}
 754
 755/*
 756 * main "reflog"
 757 */
 758
 759static const char reflog_usage[] =
 760"git reflog [ show | expire | delete | exists ]";
 761
 762int cmd_reflog(int argc, const char **argv, const char *prefix)
 763{
 764        if (argc > 1 && !strcmp(argv[1], "-h"))
 765                usage(reflog_usage);
 766
 767        /* With no command, we default to showing it. */
 768        if (argc < 2 || *argv[1] == '-')
 769                return cmd_log_reflog(argc, argv, prefix);
 770
 771        if (!strcmp(argv[1], "show"))
 772                return cmd_log_reflog(argc - 1, argv + 1, prefix);
 773
 774        if (!strcmp(argv[1], "expire"))
 775                return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 776
 777        if (!strcmp(argv[1], "delete"))
 778                return cmd_reflog_delete(argc - 1, argv + 1, prefix);
 779
 780        if (!strcmp(argv[1], "exists"))
 781                return cmd_reflog_exists(argc - 1, argv + 1, prefix);
 782
 783        return cmd_log_reflog(argc, argv, prefix);
 784}