builtin/reflog.c

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