Andrew's git - gitweb.git/blob

9ee66d4eb29e4e77f8dcb874a6d72cbef789a1de
   1#include "builtin.h"
   2#include "lockfile.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
  23enum expire_reflog_flags {
  24        EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
  25        EXPIRE_REFLOGS_UPDATE_REF = 1 << 1
  26};
  27
  28struct cmd_reflog_expire_cb {
  29        struct rev_info revs;
  30        int stalefix;
  31        int rewrite;
  32        int verbose;
  33        unsigned long expire_total;
  34        unsigned long expire_unreachable;
  35        int recno;
  36};
  37
  38struct expire_reflog_policy_cb {
  39        FILE *newlog;
  40        enum {
  41                UE_NORMAL,
  42                UE_ALWAYS,
  43                UE_HEAD
  44        } unreachable_expire_kind;
  45        struct commit_list *mark_list;
  46        unsigned long mark_limit;
  47        struct cmd_reflog_expire_cb *cmd;
  48        unsigned char last_kept_sha1[20];
  49        struct commit *tip_commit;
  50        struct commit_list *tips;
  51};
  52
  53struct expire_reflog_cb {
  54        void *policy_cb;
  55};
  56
  57struct collected_reflog {
  58        unsigned char sha1[20];
  59        char reflog[FLEX_ARRAY];
  60};
  61
  62struct collect_reflog_cb {
  63        struct collected_reflog **e;
  64        int alloc;
  65        int nr;
  66};
  67
  68#define INCOMPLETE      (1u<<10)
  69#define STUDYING        (1u<<11)
  70#define REACHABLE       (1u<<12)
  71
  72static int tree_is_complete(const unsigned char *sha1)
  73{
  74        struct tree_desc desc;
  75        struct name_entry entry;
  76        int complete;
  77        struct tree *tree;
  78
  79        tree = lookup_tree(sha1);
  80        if (!tree)
  81                return 0;
  82        if (tree->object.flags & SEEN)
  83                return 1;
  84        if (tree->object.flags & INCOMPLETE)
  85                return 0;
  86
  87        if (!tree->buffer) {
  88                enum object_type type;
  89                unsigned long size;
  90                void *data = read_sha1_file(sha1, &type, &size);
  91                if (!data) {
  92                        tree->object.flags |= INCOMPLETE;
  93                        return 0;
  94                }
  95                tree->buffer = data;
  96                tree->size = size;
  97        }
  98        init_tree_desc(&desc, tree->buffer, tree->size);
  99        complete = 1;
 100        while (tree_entry(&desc, &entry)) {
 101                if (!has_sha1_file(entry.sha1) ||
 102                    (S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
 103                        tree->object.flags |= INCOMPLETE;
 104                        complete = 0;
 105                }
 106        }
 107        free_tree_buffer(tree);
 108
 109        if (complete)
 110                tree->object.flags |= SEEN;
 111        return complete;
 112}
 113
 114static int commit_is_complete(struct commit *commit)
 115{
 116        struct object_array study;
 117        struct object_array found;
 118        int is_incomplete = 0;
 119        int i;
 120
 121        /* early return */
 122        if (commit->object.flags & SEEN)
 123                return 1;
 124        if (commit->object.flags & INCOMPLETE)
 125                return 0;
 126        /*
 127         * Find all commits that are reachable and are not marked as
 128         * SEEN.  Then make sure the trees and blobs contained are
 129         * complete.  After that, mark these commits also as SEEN.
 130         * If some of the objects that are needed to complete this
 131         * commit are missing, mark this commit as INCOMPLETE.
 132         */
 133        memset(&study, 0, sizeof(study));
 134        memset(&found, 0, sizeof(found));
 135        add_object_array(&commit->object, NULL, &study);
 136        add_object_array(&commit->object, NULL, &found);
 137        commit->object.flags |= STUDYING;
 138        while (study.nr) {
 139                struct commit *c;
 140                struct commit_list *parent;
 141
 142                c = (struct commit *)study.objects[--study.nr].item;
 143                if (!c->object.parsed && !parse_object(c->object.sha1))
 144                        c->object.flags |= INCOMPLETE;
 145
 146                if (c->object.flags & INCOMPLETE) {
 147                        is_incomplete = 1;
 148                        break;
 149                }
 150                else if (c->object.flags & SEEN)
 151                        continue;
 152                for (parent = c->parents; parent; parent = parent->next) {
 153                        struct commit *p = parent->item;
 154                        if (p->object.flags & STUDYING)
 155                                continue;
 156                        p->object.flags |= STUDYING;
 157                        add_object_array(&p->object, NULL, &study);
 158                        add_object_array(&p->object, NULL, &found);
 159                }
 160        }
 161        if (!is_incomplete) {
 162                /*
 163                 * make sure all commits in "found" array have all the
 164                 * necessary objects.
 165                 */
 166                for (i = 0; i < found.nr; i++) {
 167                        struct commit *c =
 168                                (struct commit *)found.objects[i].item;
 169                        if (!tree_is_complete(c->tree->object.sha1)) {
 170                                is_incomplete = 1;
 171                                c->object.flags |= INCOMPLETE;
 172                        }
 173                }
 174                if (!is_incomplete) {
 175                        /* mark all found commits as complete, iow SEEN */
 176                        for (i = 0; i < found.nr; i++)
 177                                found.objects[i].item->flags |= SEEN;
 178                }
 179        }
 180        /* clear flags from the objects we traversed */
 181        for (i = 0; i < found.nr; i++)
 182                found.objects[i].item->flags &= ~STUDYING;
 183        if (is_incomplete)
 184                commit->object.flags |= INCOMPLETE;
 185        else {
 186                /*
 187                 * If we come here, we have (1) traversed the ancestry chain
 188                 * from the "commit" until we reach SEEN commits (which are
 189                 * known to be complete), and (2) made sure that the commits
 190                 * encountered during the above traversal refer to trees that
 191                 * are complete.  Which means that we know *all* the commits
 192                 * we have seen during this process are complete.
 193                 */
 194                for (i = 0; i < found.nr; i++)
 195                        found.objects[i].item->flags |= SEEN;
 196        }
 197        /* free object arrays */
 198        free(study.objects);
 199        free(found.objects);
 200        return !is_incomplete;
 201}
 202
 203static int keep_entry(struct commit **it, unsigned char *sha1)
 204{
 205        struct commit *commit;
 206
 207        if (is_null_sha1(sha1))
 208                return 1;
 209        commit = lookup_commit_reference_gently(sha1, 1);
 210        if (!commit)
 211                return 0;
 212
 213        /*
 214         * Make sure everything in this commit exists.
 215         *
 216         * We have walked all the objects reachable from the refs
 217         * and cache earlier.  The commits reachable by this commit
 218         * must meet SEEN commits -- and then we should mark them as
 219         * SEEN as well.
 220         */
 221        if (!commit_is_complete(commit))
 222                return 0;
 223        *it = commit;
 224        return 1;
 225}
 226
 227/*
 228 * Starting from commits in the cb->mark_list, mark commits that are
 229 * reachable from them.  Stop the traversal at commits older than
 230 * the expire_limit and queue them back, so that the caller can call
 231 * us again to restart the traversal with longer expire_limit.
 232 */
 233static void mark_reachable(struct expire_reflog_policy_cb *cb)
 234{
 235        struct commit *commit;
 236        struct commit_list *pending;
 237        unsigned long expire_limit = cb->mark_limit;
 238        struct commit_list *leftover = NULL;
 239
 240        for (pending = cb->mark_list; pending; pending = pending->next)
 241                pending->item->object.flags &= ~REACHABLE;
 242
 243        pending = cb->mark_list;
 244        while (pending) {
 245                struct commit_list *entry = pending;
 246                struct commit_list *parent;
 247                pending = entry->next;
 248                commit = entry->item;
 249                free(entry);
 250                if (commit->object.flags & REACHABLE)
 251                        continue;
 252                if (parse_commit(commit))
 253                        continue;
 254                commit->object.flags |= REACHABLE;
 255                if (commit->date < expire_limit) {
 256                        commit_list_insert(commit, &leftover);
 257                        continue;
 258                }
 259                commit->object.flags |= REACHABLE;
 260                parent = commit->parents;
 261                while (parent) {
 262                        commit = parent->item;
 263                        parent = parent->next;
 264                        if (commit->object.flags & REACHABLE)
 265                                continue;
 266                        commit_list_insert(commit, &pending);
 267                }
 268        }
 269        cb->mark_list = leftover;
 270}
 271
 272static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, unsigned char *sha1)
 273{
 274        /*
 275         * We may or may not have the commit yet - if not, look it
 276         * up using the supplied sha1.
 277         */
 278        if (!commit) {
 279                if (is_null_sha1(sha1))
 280                        return 0;
 281
 282                commit = lookup_commit_reference_gently(sha1, 1);
 283
 284                /* Not a commit -- keep it */
 285                if (!commit)
 286                        return 0;
 287        }
 288
 289        /* Reachable from the current ref?  Don't prune. */
 290        if (commit->object.flags & REACHABLE)
 291                return 0;
 292
 293        if (cb->mark_list && cb->mark_limit) {
 294                cb->mark_limit = 0; /* dig down to the root */
 295                mark_reachable(cb);
 296        }
 297
 298        return !(commit->object.flags & REACHABLE);
 299}
 300
 301/*
 302 * Return true iff the specified reflog entry should be expired.
 303 */
 304static int should_expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 305                                    const char *email, unsigned long timestamp, int tz,
 306                                    const char *message, void *cb_data)
 307{
 308        struct expire_reflog_policy_cb *cb = cb_data;
 309        struct commit *old, *new;
 310
 311        if (timestamp < cb->cmd->expire_total)
 312                return 1;
 313
 314        old = new = NULL;
 315        if (cb->cmd->stalefix &&
 316            (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
 317                return 1;
 318
 319        if (timestamp < cb->cmd->expire_unreachable) {
 320                if (cb->unreachable_expire_kind == UE_ALWAYS)
 321                        return 1;
 322                if (unreachable(cb, old, osha1) || unreachable(cb, new, nsha1))
 323                        return 1;
 324        }
 325
 326        if (cb->cmd->recno && --(cb->cmd->recno) == 0)
 327                return 1;
 328
 329        return 0;
 330}
 331
 332static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 333                const char *email, unsigned long timestamp, int tz,
 334                const char *message, void *cb_data)
 335{
 336        struct expire_reflog_cb *cb = cb_data;
 337        struct expire_reflog_policy_cb *policy_cb = cb->policy_cb;
 338
 339        if (policy_cb->cmd->rewrite)
 340                osha1 = policy_cb->last_kept_sha1;
 341
 342        if (should_expire_reflog_ent(osha1, nsha1, email, timestamp, tz,
 343                                     message, policy_cb)) {
 344                if (!policy_cb->newlog)
 345                        printf("would prune %s", message);
 346                else if (policy_cb->cmd->verbose)
 347                        printf("prune %s", message);
 348        } else {
 349                if (policy_cb->newlog) {
 350                        char sign = (tz < 0) ? '-' : '+';
 351                        int zone = (tz < 0) ? (-tz) : tz;
 352                        fprintf(policy_cb->newlog, "%s %s %s %lu %c%04d\t%s",
 353                                sha1_to_hex(osha1), sha1_to_hex(nsha1),
 354                                email, timestamp, sign, zone,
 355                                message);
 356                        hashcpy(policy_cb->last_kept_sha1, nsha1);
 357                }
 358                if (policy_cb->cmd->verbose)
 359                        printf("keep %s", message);
 360        }
 361        return 0;
 362}
 363
 364static int push_tip_to_list(const char *refname, const unsigned char *sha1,
 365                            int flags, void *cb_data)
 366{
 367        struct commit_list **list = cb_data;
 368        struct commit *tip_commit;
 369        if (flags & REF_ISSYMREF)
 370                return 0;
 371        tip_commit = lookup_commit_reference_gently(sha1, 1);
 372        if (!tip_commit)
 373                return 0;
 374        commit_list_insert(tip_commit, list);
 375        return 0;
 376}
 377
 378static void reflog_expiry_prepare(const char *refname,
 379                                  const unsigned char *sha1,
 380                                  struct expire_reflog_policy_cb *cb)
 381{
 382        if (!cb->cmd->expire_unreachable || !strcmp(refname, "HEAD")) {
 383                cb->tip_commit = NULL;
 384                cb->unreachable_expire_kind = UE_HEAD;
 385        } else {
 386                cb->tip_commit = lookup_commit_reference_gently(sha1, 1);
 387                if (!cb->tip_commit)
 388                        cb->unreachable_expire_kind = UE_ALWAYS;
 389                else
 390                        cb->unreachable_expire_kind = UE_NORMAL;
 391        }
 392
 393        if (cb->cmd->expire_unreachable <= cb->cmd->expire_total)
 394                cb->unreachable_expire_kind = UE_ALWAYS;
 395
 396        cb->mark_list = NULL;
 397        cb->tips = NULL;
 398        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 399                if (cb->unreachable_expire_kind == UE_HEAD) {
 400                        struct commit_list *elem;
 401                        for_each_ref(push_tip_to_list, &cb->tips);
 402                        for (elem = cb->tips; elem; elem = elem->next)
 403                                commit_list_insert(elem->item, &cb->mark_list);
 404                } else {
 405                        commit_list_insert(cb->tip_commit, &cb->mark_list);
 406                }
 407                cb->mark_limit = cb->cmd->expire_total;
 408                mark_reachable(cb);
 409        }
 410}
 411
 412static void reflog_expiry_cleanup(struct expire_reflog_policy_cb *cb)
 413{
 414        if (cb->unreachable_expire_kind != UE_ALWAYS) {
 415                if (cb->unreachable_expire_kind == UE_HEAD) {
 416                        struct commit_list *elem;
 417                        for (elem = cb->tips; elem; elem = elem->next)
 418                                clear_commit_marks(elem->item, REACHABLE);
 419                        free_commit_list(cb->tips);
 420                } else {
 421                        clear_commit_marks(cb->tip_commit, REACHABLE);
 422                }
 423        }
 424}
 425
 426static int expire_reflog(const char *refname, const unsigned char *sha1,
 427                         unsigned int flags, struct cmd_reflog_expire_cb *cmd)
 428{
 429        static struct lock_file reflog_lock;
 430        struct expire_reflog_cb cb;
 431        struct expire_reflog_policy_cb policy_cb;
 432        struct ref_lock *lock;
 433        char *log_file;
 434        int status = 0;
 435
 436        memset(&cb, 0, sizeof(cb));
 437        memset(&policy_cb, 0, sizeof(policy_cb));
 438        cb.policy_cb = &policy_cb;
 439
 440        /*
 441         * The reflog file is locked by holding the lock on the
 442         * reference itself, plus we might need to update the
 443         * reference if --updateref was specified:
 444         */
 445        lock = lock_any_ref_for_update(refname, sha1, 0, NULL);
 446        if (!lock)
 447                return error("cannot lock ref '%s'", refname);
 448        if (!reflog_exists(refname)) {
 449                unlock_ref(lock);
 450                return 0;
 451        }
 452
 453        log_file = git_pathdup("logs/%s", refname);
 454        if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
 455                /*
 456                 * Even though holding $GIT_DIR/logs/$reflog.lock has
 457                 * no locking implications, we use the lock_file
 458                 * machinery here anyway because it does a lot of the
 459                 * work we need, including cleaning up if the program
 460                 * exits unexpectedly.
 461                 */
 462                if (hold_lock_file_for_update(&reflog_lock, log_file, 0) < 0) {
 463                        struct strbuf err = STRBUF_INIT;
 464                        unable_to_lock_message(log_file, errno, &err);
 465                        error("%s", err.buf);
 466                        strbuf_release(&err);
 467                        goto failure;
 468                }
 469                policy_cb.newlog = fdopen_lock_file(&reflog_lock, "w");
 470                if (!policy_cb.newlog) {
 471                        error("cannot fdopen %s (%s)",
 472                              reflog_lock.filename.buf, strerror(errno));
 473                        goto failure;
 474                }
 475        }
 476
 477        policy_cb.cmd = cmd;
 478
 479        reflog_expiry_prepare(refname, sha1, &policy_cb);
 480        for_each_reflog_ent(refname, expire_reflog_ent, &cb);
 481        reflog_expiry_cleanup(&policy_cb);
 482
 483        if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
 484                if (close_lock_file(&reflog_lock)) {
 485                        status |= error("couldn't write %s: %s", log_file,
 486                                        strerror(errno));
 487                } else if ((flags & EXPIRE_REFLOGS_UPDATE_REF) &&
 488                        (write_in_full(lock->lock_fd,
 489                                sha1_to_hex(policy_cb.last_kept_sha1), 40) != 40 ||
 490                         write_str_in_full(lock->lock_fd, "\n") != 1 ||
 491                         close_ref(lock) < 0)) {
 492                        status |= error("couldn't write %s",
 493                                        lock->lk->filename.buf);
 494                        rollback_lock_file(&reflog_lock);
 495                } else if (commit_lock_file(&reflog_lock)) {
 496                        status |= error("unable to commit reflog '%s' (%s)",
 497                                        log_file, strerror(errno));
 498                } else if ((flags & EXPIRE_REFLOGS_UPDATE_REF) && commit_ref(lock)) {
 499                        status |= error("couldn't set %s", lock->ref_name);
 500                }
 501        }
 502        free(log_file);
 503        unlock_ref(lock);
 504        return status;
 505
 506 failure:
 507        rollback_lock_file(&reflog_lock);
 508        free(log_file);
 509        unlock_ref(lock);
 510        return -1;
 511}
 512
 513static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
 514{
 515        struct collected_reflog *e;
 516        struct collect_reflog_cb *cb = cb_data;
 517        size_t namelen = strlen(ref);
 518
 519        e = xmalloc(sizeof(*e) + namelen + 1);
 520        hashcpy(e->sha1, sha1);
 521        memcpy(e->reflog, ref, namelen + 1);
 522        ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
 523        cb->e[cb->nr++] = e;
 524        return 0;
 525}
 526
 527static struct reflog_expire_cfg {
 528        struct reflog_expire_cfg *next;
 529        unsigned long expire_total;
 530        unsigned long expire_unreachable;
 531        size_t len;
 532        char pattern[FLEX_ARRAY];
 533} *reflog_expire_cfg, **reflog_expire_cfg_tail;
 534
 535static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
 536{
 537        struct reflog_expire_cfg *ent;
 538
 539        if (!reflog_expire_cfg_tail)
 540                reflog_expire_cfg_tail = &reflog_expire_cfg;
 541
 542        for (ent = reflog_expire_cfg; ent; ent = ent->next)
 543                if (ent->len == len &&
 544                    !memcmp(ent->pattern, pattern, len))
 545                        return ent;
 546
 547        ent = xcalloc(1, (sizeof(*ent) + len));
 548        memcpy(ent->pattern, pattern, len);
 549        ent->len = len;
 550        *reflog_expire_cfg_tail = ent;
 551        reflog_expire_cfg_tail = &(ent->next);
 552        return ent;
 553}
 554
 555static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
 556{
 557        if (!value)
 558                return config_error_nonbool(var);
 559        if (parse_expiry_date(value, expire))
 560                return error(_("%s' for '%s' is not a valid timestamp"),
 561                             value, var);
 562        return 0;
 563}
 564
 565/* expiry timer slot */
 566#define EXPIRE_TOTAL   01
 567#define EXPIRE_UNREACH 02
 568
 569static int reflog_expire_config(const char *var, const char *value, void *cb)
 570{
 571        const char *pattern, *key;
 572        int pattern_len;
 573        unsigned long expire;
 574        int slot;
 575        struct reflog_expire_cfg *ent;
 576
 577        if (parse_config_key(var, "gc", &pattern, &pattern_len, &key) < 0)
 578                return git_default_config(var, value, cb);
 579
 580        if (!strcmp(key, "reflogexpire")) {
 581                slot = EXPIRE_TOTAL;
 582                if (parse_expire_cfg_value(var, value, &expire))
 583                        return -1;
 584        } else if (!strcmp(key, "reflogexpireunreachable")) {
 585                slot = EXPIRE_UNREACH;
 586                if (parse_expire_cfg_value(var, value, &expire))
 587                        return -1;
 588        } else
 589                return git_default_config(var, value, cb);
 590
 591        if (!pattern) {
 592                switch (slot) {
 593                case EXPIRE_TOTAL:
 594                        default_reflog_expire = expire;
 595                        break;
 596                case EXPIRE_UNREACH:
 597                        default_reflog_expire_unreachable = expire;
 598                        break;
 599                }
 600                return 0;
 601        }
 602
 603        ent = find_cfg_ent(pattern, pattern_len);
 604        if (!ent)
 605                return -1;
 606        switch (slot) {
 607        case EXPIRE_TOTAL:
 608                ent->expire_total = expire;
 609                break;
 610        case EXPIRE_UNREACH:
 611                ent->expire_unreachable = expire;
 612                break;
 613        }
 614        return 0;
 615}
 616
 617static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
 618{
 619        struct reflog_expire_cfg *ent;
 620
 621        if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
 622                return; /* both given explicitly -- nothing to tweak */
 623
 624        for (ent = reflog_expire_cfg; ent; ent = ent->next) {
 625                if (!wildmatch(ent->pattern, ref, 0, NULL)) {
 626                        if (!(slot & EXPIRE_TOTAL))
 627                                cb->expire_total = ent->expire_total;
 628                        if (!(slot & EXPIRE_UNREACH))
 629                                cb->expire_unreachable = ent->expire_unreachable;
 630                        return;
 631                }
 632        }
 633
 634        /*
 635         * If unconfigured, make stash never expire
 636         */
 637        if (!strcmp(ref, "refs/stash")) {
 638                if (!(slot & EXPIRE_TOTAL))
 639                        cb->expire_total = 0;
 640                if (!(slot & EXPIRE_UNREACH))
 641                        cb->expire_unreachable = 0;
 642                return;
 643        }
 644
 645        /* Nothing matched -- use the default value */
 646        if (!(slot & EXPIRE_TOTAL))
 647                cb->expire_total = default_reflog_expire;
 648        if (!(slot & EXPIRE_UNREACH))
 649                cb->expire_unreachable = default_reflog_expire_unreachable;
 650}
 651
 652static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 653{
 654        struct cmd_reflog_expire_cb cb;
 655        unsigned long now = time(NULL);
 656        int i, status, do_all;
 657        int explicit_expiry = 0;
 658        unsigned int flags = 0;
 659
 660        default_reflog_expire_unreachable = now - 30 * 24 * 3600;
 661        default_reflog_expire = now - 90 * 24 * 3600;
 662        git_config(reflog_expire_config, NULL);
 663
 664        save_commit_buffer = 0;
 665        do_all = status = 0;
 666        memset(&cb, 0, sizeof(cb));
 667
 668        cb.expire_total = default_reflog_expire;
 669        cb.expire_unreachable = default_reflog_expire_unreachable;
 670
 671        for (i = 1; i < argc; i++) {
 672                const char *arg = argv[i];
 673                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 674                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 675                else if (starts_with(arg, "--expire=")) {
 676                        if (parse_expiry_date(arg + 9, &cb.expire_total))
 677                                die(_("'%s' is not a valid timestamp"), arg);
 678                        explicit_expiry |= EXPIRE_TOTAL;
 679                }
 680                else if (starts_with(arg, "--expire-unreachable=")) {
 681                        if (parse_expiry_date(arg + 21, &cb.expire_unreachable))
 682                                die(_("'%s' is not a valid timestamp"), arg);
 683                        explicit_expiry |= EXPIRE_UNREACH;
 684                }
 685                else if (!strcmp(arg, "--stale-fix"))
 686                        cb.stalefix = 1;
 687                else if (!strcmp(arg, "--rewrite"))
 688                        cb.rewrite = 1;
 689                else if (!strcmp(arg, "--updateref"))
 690                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 691                else if (!strcmp(arg, "--all"))
 692                        do_all = 1;
 693                else if (!strcmp(arg, "--verbose"))
 694                        cb.verbose = 1;
 695                else if (!strcmp(arg, "--")) {
 696                        i++;
 697                        break;
 698                }
 699                else if (arg[0] == '-')
 700                        usage(reflog_expire_usage);
 701                else
 702                        break;
 703        }
 704
 705        /*
 706         * We can trust the commits and objects reachable from refs
 707         * even in older repository.  We cannot trust what's reachable
 708         * from reflog if the repository was pruned with older git.
 709         */
 710        if (cb.stalefix) {
 711                init_revisions(&cb.revs, prefix);
 712                if (cb.verbose)
 713                        printf("Marking reachable objects...");
 714                mark_reachable_objects(&cb.revs, 0, 0, NULL);
 715                if (cb.verbose)
 716                        putchar('\n');
 717        }
 718
 719        if (do_all) {
 720                struct collect_reflog_cb collected;
 721                int i;
 722
 723                memset(&collected, 0, sizeof(collected));
 724                for_each_reflog(collect_reflog, &collected);
 725                for (i = 0; i < collected.nr; i++) {
 726                        struct collected_reflog *e = collected.e[i];
 727                        set_reflog_expiry_param(&cb, explicit_expiry, e->reflog);
 728                        status |= expire_reflog(e->reflog, e->sha1, flags, &cb);
 729                        free(e);
 730                }
 731                free(collected.e);
 732        }
 733
 734        for (; i < argc; i++) {
 735                char *ref;
 736                unsigned char sha1[20];
 737                if (!dwim_log(argv[i], strlen(argv[i]), sha1, &ref)) {
 738                        status |= error("%s points nowhere!", argv[i]);
 739                        continue;
 740                }
 741                set_reflog_expiry_param(&cb, explicit_expiry, ref);
 742                status |= expire_reflog(ref, sha1, flags, &cb);
 743        }
 744        return status;
 745}
 746
 747static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 748                const char *email, unsigned long timestamp, int tz,
 749                const char *message, void *cb_data)
 750{
 751        struct cmd_reflog_expire_cb *cb = cb_data;
 752        if (!cb->expire_total || timestamp < cb->expire_total)
 753                cb->recno++;
 754        return 0;
 755}
 756
 757static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 758{
 759        struct cmd_reflog_expire_cb cb;
 760        int i, status = 0;
 761        unsigned int flags = 0;
 762
 763        memset(&cb, 0, sizeof(cb));
 764
 765        for (i = 1; i < argc; i++) {
 766                const char *arg = argv[i];
 767                if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 768                        flags |= EXPIRE_REFLOGS_DRY_RUN;
 769                else if (!strcmp(arg, "--rewrite"))
 770                        cb.rewrite = 1;
 771                else if (!strcmp(arg, "--updateref"))
 772                        flags |= EXPIRE_REFLOGS_UPDATE_REF;
 773                else if (!strcmp(arg, "--verbose"))
 774                        cb.verbose = 1;
 775                else if (!strcmp(arg, "--")) {
 776                        i++;
 777                        break;
 778                }
 779                else if (arg[0] == '-')
 780                        usage(reflog_delete_usage);
 781                else
 782                        break;
 783        }
 784
 785        if (argc - i < 1)
 786                return error("Nothing to delete?");
 787
 788        for ( ; i < argc; i++) {
 789                const char *spec = strstr(argv[i], "@{");
 790                unsigned char sha1[20];
 791                char *ep, *ref;
 792                int recno;
 793
 794                if (!spec) {
 795                        status |= error("Not a reflog: %s", argv[i]);
 796                        continue;
 797                }
 798
 799                if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
 800                        status |= error("no reflog for '%s'", argv[i]);
 801                        continue;
 802                }
 803
 804                recno = strtoul(spec + 2, &ep, 10);
 805                if (*ep == '}') {
 806                        cb.recno = -recno;
 807                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 808                } else {
 809                        cb.expire_total = approxidate(spec + 2);
 810                        for_each_reflog_ent(ref, count_reflog_ent, &cb);
 811                        cb.expire_total = 0;
 812                }
 813
 814                status |= expire_reflog(ref, sha1, flags, &cb);
 815                free(ref);
 816        }
 817        return status;
 818}
 819
 820/*
 821 * main "reflog"
 822 */
 823
 824static const char reflog_usage[] =
 825"git reflog [ show | expire | delete ]";
 826
 827int cmd_reflog(int argc, const char **argv, const char *prefix)
 828{
 829        if (argc > 1 && !strcmp(argv[1], "-h"))
 830                usage(reflog_usage);
 831
 832        /* With no command, we default to showing it. */
 833        if (argc < 2 || *argv[1] == '-')
 834                return cmd_log_reflog(argc, argv, prefix);
 835
 836        if (!strcmp(argv[1], "show"))
 837                return cmd_log_reflog(argc - 1, argv + 1, prefix);
 838
 839        if (!strcmp(argv[1], "expire"))
 840                return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 841
 842        if (!strcmp(argv[1], "delete"))
 843                return cmd_reflog_delete(argc - 1, argv + 1, prefix);
 844
 845        return cmd_log_reflog(argc, argv, prefix);
 846}