builtin/reflog.c

   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 /* NEEDSWORK: switch to using parse_options */
  12 static const char reflog_expire_usage[] =
  13 "git reflog expire [--expire=<time>] [--expire-unreachable=<time>] [--rewrite] [--updateref] [--stale-fix] [--dry-run | -n] [--verbose] [--all] <refs>...";
  14 static const char reflog_delete_usage[] =
  15 "git reflog delete [--rewrite] [--updateref] [--dry-run | -n] [--verbose] <refs>...";
  16
  17 static unsigned long default_reflog_expire;
  18 static unsigned long default_reflog_expire_unreachable;
  19
  20 struct cmd_reflog_expire_cb {
  21         struct rev_info revs;
  22         int stalefix;
  23         unsigned long expire_total;
  24         unsigned long expire_unreachable;
  25         int recno;
  26 };
  27
  28 struct expire_reflog_policy_cb {
  29         enum {
  30                 UE_NORMAL,
  31                 UE_ALWAYS,
  32                 UE_HEAD
  33         } unreachable_expire_kind;
  34         struct commit_list *mark_list;
  35         unsigned long mark_limit;
  36         struct cmd_reflog_expire_cb cmd;
  37         struct commit *tip_commit;
  38         struct commit_list *tips;
  39 };
  40
  41 struct collected_reflog {
  42         unsigned char sha1[20];
  43         char reflog[FLEX_ARRAY];
  44 };
  45
  46 struct collect_reflog_cb {
  47         struct collected_reflog **e;
  48         int alloc;
  49         int nr;
  50 };
  51
  52 #define INCOMPLETE      (1u<<10)
  53 #define STUDYING        (1u<<11)
  54 #define REACHABLE       (1u<<12)
  55
  56 static int tree_is_complete(const unsigned char *sha1)
  57 {
  58         struct tree_desc desc;
  59         struct name_entry entry;
  60         int complete;
  61         struct tree *tree;
  62
  63         tree = lookup_tree(sha1);
  64         if (!tree)
  65                 return 0;
  66         if (tree->object.flags & SEEN)
  67                 return 1;
  68         if (tree->object.flags & INCOMPLETE)
  69                 return 0;
  70
  71         if (!tree->buffer) {
  72                 enum object_type type;
  73                 unsigned long size;
  74                 void *data = read_sha1_file(sha1, &type, &size);
  75                 if (!data) {
  76                         tree->object.flags |= INCOMPLETE;
  77                         return 0;
  78                 }
  79                 tree->buffer = data;
  80                 tree->size = size;
  81         }
  82         init_tree_desc(&desc, tree->buffer, tree->size);
  83         complete = 1;
  84         while (tree_entry(&desc, &entry)) {
  85                 if (!has_sha1_file(entry.sha1) ||
  86                     (S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
  87                         tree->object.flags |= INCOMPLETE;
  88                         complete = 0;
  89                 }
  90         }
  91         free_tree_buffer(tree);
  92
  93         if (complete)
  94                 tree->object.flags |= SEEN;
  95         return complete;
  96 }
  97
  98 static int commit_is_complete(struct commit *commit)
  99 {
 100         struct object_array study;
 101         struct object_array found;
 102         int is_incomplete = 0;
 103         int i;
 104
 105         /* early return */
 106         if (commit->object.flags & SEEN)
 107                 return 1;
 108         if (commit->object.flags & INCOMPLETE)
 109                 return 0;
 110         /*
 111          * Find all commits that are reachable and are not marked as
 112          * SEEN.  Then make sure the trees and blobs contained are
 113          * complete.  After that, mark these commits also as SEEN.
 114          * If some of the objects that are needed to complete this
 115          * commit are missing, mark this commit as INCOMPLETE.
 116          */
 117         memset(&study, 0, sizeof(study));
 118         memset(&found, 0, sizeof(found));
 119         add_object_array(&commit->object, NULL, &study);
 120         add_object_array(&commit->object, NULL, &found);
 121         commit->object.flags |= STUDYING;
 122         while (study.nr) {
 123                 struct commit *c;
 124                 struct commit_list *parent;
 125
 126                 c = (struct commit *)study.objects[--study.nr].item;
 127                 if (!c->object.parsed && !parse_object(c->object.sha1))
 128                         c->object.flags |= INCOMPLETE;
 129
 130                 if (c->object.flags & INCOMPLETE) {
 131                         is_incomplete = 1;
 132                         break;
 133                 }
 134                 else if (c->object.flags & SEEN)
 135                         continue;
 136                 for (parent = c->parents; parent; parent = parent->next) {
 137                         struct commit *p = parent->item;
 138                         if (p->object.flags & STUDYING)
 139                                 continue;
 140                         p->object.flags |= STUDYING;
 141                         add_object_array(&p->object, NULL, &study);
 142                         add_object_array(&p->object, NULL, &found);
 143                 }
 144         }
 145         if (!is_incomplete) {
 146                 /*
 147                  * make sure all commits in "found" array have all the
 148                  * necessary objects.
 149                  */
 150                 for (i = 0; i < found.nr; i++) {
 151                         struct commit *c =
 152                                 (struct commit *)found.objects[i].item;
 153                         if (!tree_is_complete(c->tree->object.sha1)) {
 154                                 is_incomplete = 1;
 155                                 c->object.flags |= INCOMPLETE;
 156                         }
 157                 }
 158                 if (!is_incomplete) {
 159                         /* mark all found commits as complete, iow SEEN */
 160                         for (i = 0; i < found.nr; i++)
 161                                 found.objects[i].item->flags |= SEEN;
 162                 }
 163         }
 164         /* clear flags from the objects we traversed */
 165         for (i = 0; i < found.nr; i++)
 166                 found.objects[i].item->flags &= ~STUDYING;
 167         if (is_incomplete)
 168                 commit->object.flags |= INCOMPLETE;
 169         else {
 170                 /*
 171                  * If we come here, we have (1) traversed the ancestry chain
 172                  * from the "commit" until we reach SEEN commits (which are
 173                  * known to be complete), and (2) made sure that the commits
 174                  * encountered during the above traversal refer to trees that
 175                  * are complete.  Which means that we know *all* the commits
 176                  * we have seen during this process are complete.
 177                  */
 178                 for (i = 0; i < found.nr; i++)
 179                         found.objects[i].item->flags |= SEEN;
 180         }
 181         /* free object arrays */
 182         free(study.objects);
 183         free(found.objects);
 184         return !is_incomplete;
 185 }
 186
 187 static int keep_entry(struct commit **it, unsigned char *sha1)
 188 {
 189         struct commit *commit;
 190
 191         if (is_null_sha1(sha1))
 192                 return 1;
 193         commit = lookup_commit_reference_gently(sha1, 1);
 194         if (!commit)
 195                 return 0;
 196
 197         /*
 198          * Make sure everything in this commit exists.
 199          *
 200          * We have walked all the objects reachable from the refs
 201          * and cache earlier.  The commits reachable by this commit
 202          * must meet SEEN commits -- and then we should mark them as
 203          * SEEN as well.
 204          */
 205         if (!commit_is_complete(commit))
 206                 return 0;
 207         *it = commit;
 208         return 1;
 209 }
 210
 211 /*
 212  * Starting from commits in the cb->mark_list, mark commits that are
 213  * reachable from them.  Stop the traversal at commits older than
 214  * the expire_limit and queue them back, so that the caller can call
 215  * us again to restart the traversal with longer expire_limit.
 216  */
 217 static void mark_reachable(struct expire_reflog_policy_cb *cb)
 218 {
 219         struct commit *commit;
 220         struct commit_list *pending;
 221         unsigned long expire_limit = cb->mark_limit;
 222         struct commit_list *leftover = NULL;
 223
 224         for (pending = cb->mark_list; pending; pending = pending->next)
 225                 pending->item->object.flags &= ~REACHABLE;
 226
 227         pending = cb->mark_list;
 228         while (pending) {
 229                 struct commit_list *entry = pending;
 230                 struct commit_list *parent;
 231                 pending = entry->next;
 232                 commit = entry->item;
 233                 free(entry);
 234                 if (commit->object.flags & REACHABLE)
 235                         continue;
 236                 if (parse_commit(commit))
 237                         continue;
 238                 commit->object.flags |= REACHABLE;
 239                 if (commit->date < expire_limit) {
 240                         commit_list_insert(commit, &leftover);
 241                         continue;
 242                 }
 243                 commit->object.flags |= REACHABLE;
 244                 parent = commit->parents;
 245                 while (parent) {
 246                         commit = parent->item;
 247                         parent = parent->next;
 248                         if (commit->object.flags & REACHABLE)
 249                                 continue;
 250                         commit_list_insert(commit, &pending);
 251                 }
 252         }
 253         cb->mark_list = leftover;
 254 }
 255
 256 static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, unsigned char *sha1)
 257 {
 258         /*
 259          * We may or may not have the commit yet - if not, look it
 260          * up using the supplied sha1.
 261          */
 262         if (!commit) {
 263                 if (is_null_sha1(sha1))
 264                         return 0;
 265
 266                 commit = lookup_commit_reference_gently(sha1, 1);
 267
 268                 /* Not a commit -- keep it */
 269                 if (!commit)
 270                         return 0;
 271         }
 272
 273         /* Reachable from the current ref?  Don't prune. */
 274         if (commit->object.flags & REACHABLE)
 275                 return 0;
 276
 277         if (cb->mark_list && cb->mark_limit) {
 278                 cb->mark_limit = 0; /* dig down to the root */
 279                 mark_reachable(cb);
 280         }
 281
 282         return !(commit->object.flags & REACHABLE);
 283 }
 284
 285 /*
 286  * Return true iff the specified reflog entry should be expired.
 287  */
 288 static int should_expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 289                                     const char *email, unsigned long timestamp, int tz,
 290                                     const char *message, void *cb_data)
 291 {
 292         struct expire_reflog_policy_cb *cb = cb_data;
 293         struct commit *old, *new;
 294
 295         if (timestamp < cb->cmd.expire_total)
 296                 return 1;
 297
 298         old = new = NULL;
 299         if (cb->cmd.stalefix &&
 300             (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
 301                 return 1;
 302
 303         if (timestamp < cb->cmd.expire_unreachable) {
 304                 if (cb->unreachable_expire_kind == UE_ALWAYS)
 305                         return 1;
 306                 if (unreachable(cb, old, osha1) || unreachable(cb, new, nsha1))
 307                         return 1;
 308         }
 309
 310         if (cb->cmd.recno && --(cb->cmd.recno) == 0)
 311                 return 1;
 312
 313         return 0;
 314 }
 315
 316 static int push_tip_to_list(const char *refname, const unsigned char *sha1,
 317                             int flags, void *cb_data)
 318 {
 319         struct commit_list **list = cb_data;
 320         struct commit *tip_commit;
 321         if (flags & REF_ISSYMREF)
 322                 return 0;
 323         tip_commit = lookup_commit_reference_gently(sha1, 1);
 324         if (!tip_commit)
 325                 return 0;
 326         commit_list_insert(tip_commit, list);
 327         return 0;
 328 }
 329
 330 static void reflog_expiry_prepare(const char *refname,
 331                                   const unsigned char *sha1,
 332                                   void *cb_data)
 333 {
 334         struct expire_reflog_policy_cb *cb = cb_data;
 335
 336         if (!cb->cmd.expire_unreachable || !strcmp(refname, "HEAD")) {
 337                 cb->tip_commit = NULL;
 338                 cb->unreachable_expire_kind = UE_HEAD;
 339         } else {
 340                 cb->tip_commit = lookup_commit_reference_gently(sha1, 1);
 341                 if (!cb->tip_commit)
 342                         cb->unreachable_expire_kind = UE_ALWAYS;
 343                 else
 344                         cb->unreachable_expire_kind = UE_NORMAL;
 345         }
 346
 347         if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
 348                 cb->unreachable_expire_kind = UE_ALWAYS;
 349
 350         cb->mark_list = NULL;
 351         cb->tips = NULL;
 352         if (cb->unreachable_expire_kind != UE_ALWAYS) {
 353                 if (cb->unreachable_expire_kind == UE_HEAD) {
 354                         struct commit_list *elem;
 355                         for_each_ref(push_tip_to_list, &cb->tips);
 356                         for (elem = cb->tips; elem; elem = elem->next)
 357                                 commit_list_insert(elem->item, &cb->mark_list);
 358                 } else {
 359                         commit_list_insert(cb->tip_commit, &cb->mark_list);
 360                 }
 361                 cb->mark_limit = cb->cmd.expire_total;
 362                 mark_reachable(cb);
 363         }
 364 }
 365
 366 static void reflog_expiry_cleanup(void *cb_data)
 367 {
 368         struct expire_reflog_policy_cb *cb = cb_data;
 369
 370         if (cb->unreachable_expire_kind != UE_ALWAYS) {
 371                 if (cb->unreachable_expire_kind == UE_HEAD) {
 372                         struct commit_list *elem;
 373                         for (elem = cb->tips; elem; elem = elem->next)
 374                                 clear_commit_marks(elem->item, REACHABLE);
 375                         free_commit_list(cb->tips);
 376                 } else {
 377                         clear_commit_marks(cb->tip_commit, REACHABLE);
 378                 }
 379         }
 380 }
 381
 382 static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
 383 {
 384         struct collected_reflog *e;
 385         struct collect_reflog_cb *cb = cb_data;
 386         size_t namelen = strlen(ref);
 387
 388         e = xmalloc(sizeof(*e) + namelen + 1);
 389         hashcpy(e->sha1, sha1);
 390         memcpy(e->reflog, ref, namelen + 1);
 391         ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
 392         cb->e[cb->nr++] = e;
 393         return 0;
 394 }
 395
 396 static struct reflog_expire_cfg {
 397         struct reflog_expire_cfg *next;
 398         unsigned long expire_total;
 399         unsigned long expire_unreachable;
 400         size_t len;
 401         char pattern[FLEX_ARRAY];
 402 } *reflog_expire_cfg, **reflog_expire_cfg_tail;
 403
 404 static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
 405 {
 406         struct reflog_expire_cfg *ent;
 407
 408         if (!reflog_expire_cfg_tail)
 409                 reflog_expire_cfg_tail = &reflog_expire_cfg;
 410
 411         for (ent = reflog_expire_cfg; ent; ent = ent->next)
 412                 if (ent->len == len &&
 413                     !memcmp(ent->pattern, pattern, len))
 414                         return ent;
 415
 416         ent = xcalloc(1, (sizeof(*ent) + len));
 417         memcpy(ent->pattern, pattern, len);
 418         ent->len = len;
 419         *reflog_expire_cfg_tail = ent;
 420         reflog_expire_cfg_tail = &(ent->next);
 421         return ent;
 422 }
 423
 424 static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
 425 {
 426         if (!value)
 427                 return config_error_nonbool(var);
 428         if (parse_expiry_date(value, expire))
 429                 return error(_("%s' for '%s' is not a valid timestamp"),
 430                              value, var);
 431         return 0;
 432 }
 433
 434 /* expiry timer slot */
 435 #define EXPIRE_TOTAL   01
 436 #define EXPIRE_UNREACH 02
 437
 438 static int reflog_expire_config(const char *var, const char *value, void *cb)
 439 {
 440         const char *pattern, *key;
 441         int pattern_len;
 442         unsigned long expire;
 443         int slot;
 444         struct reflog_expire_cfg *ent;
 445
 446         if (parse_config_key(var, "gc", &pattern, &pattern_len, &key) < 0)
 447                 return git_default_config(var, value, cb);
 448
 449         if (!strcmp(key, "reflogexpire")) {
 450                 slot = EXPIRE_TOTAL;
 451                 if (parse_expire_cfg_value(var, value, &expire))
 452                         return -1;
 453         } else if (!strcmp(key, "reflogexpireunreachable")) {
 454                 slot = EXPIRE_UNREACH;
 455                 if (parse_expire_cfg_value(var, value, &expire))
 456                         return -1;
 457         } else
 458                 return git_default_config(var, value, cb);
 459
 460         if (!pattern) {
 461                 switch (slot) {
 462                 case EXPIRE_TOTAL:
 463                         default_reflog_expire = expire;
 464                         break;
 465                 case EXPIRE_UNREACH:
 466                         default_reflog_expire_unreachable = expire;
 467                         break;
 468                 }
 469                 return 0;
 470         }
 471
 472         ent = find_cfg_ent(pattern, pattern_len);
 473         if (!ent)
 474                 return -1;
 475         switch (slot) {
 476         case EXPIRE_TOTAL:
 477                 ent->expire_total = expire;
 478                 break;
 479         case EXPIRE_UNREACH:
 480                 ent->expire_unreachable = expire;
 481                 break;
 482         }
 483         return 0;
 484 }
 485
 486 static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
 487 {
 488         struct reflog_expire_cfg *ent;
 489
 490         if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
 491                 return; /* both given explicitly -- nothing to tweak */
 492
 493         for (ent = reflog_expire_cfg; ent; ent = ent->next) {
 494                 if (!wildmatch(ent->pattern, ref, 0, NULL)) {
 495                         if (!(slot & EXPIRE_TOTAL))
 496                                 cb->expire_total = ent->expire_total;
 497                         if (!(slot & EXPIRE_UNREACH))
 498                                 cb->expire_unreachable = ent->expire_unreachable;
 499                         return;
 500                 }
 501         }
 502
 503         /*
 504          * If unconfigured, make stash never expire
 505          */
 506         if (!strcmp(ref, "refs/stash")) {
 507                 if (!(slot & EXPIRE_TOTAL))
 508                         cb->expire_total = 0;
 509                 if (!(slot & EXPIRE_UNREACH))
 510                         cb->expire_unreachable = 0;
 511                 return;
 512         }
 513
 514         /* Nothing matched -- use the default value */
 515         if (!(slot & EXPIRE_TOTAL))
 516                 cb->expire_total = default_reflog_expire;
 517         if (!(slot & EXPIRE_UNREACH))
 518                 cb->expire_unreachable = default_reflog_expire_unreachable;
 519 }
 520
 521 static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 522 {
 523         struct expire_reflog_policy_cb cb;
 524         unsigned long now = time(NULL);
 525         int i, status, do_all;
 526         int explicit_expiry = 0;
 527         unsigned int flags = 0;
 528
 529         default_reflog_expire_unreachable = now - 30 * 24 * 3600;
 530         default_reflog_expire = now - 90 * 24 * 3600;
 531         git_config(reflog_expire_config, NULL);
 532
 533         save_commit_buffer = 0;
 534         do_all = status = 0;
 535         memset(&cb, 0, sizeof(cb));
 536
 537         cb.cmd.expire_total = default_reflog_expire;
 538         cb.cmd.expire_unreachable = default_reflog_expire_unreachable;
 539
 540         for (i = 1; i < argc; i++) {
 541                 const char *arg = argv[i];
 542                 if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 543                         flags |= EXPIRE_REFLOGS_DRY_RUN;
 544                 else if (starts_with(arg, "--expire=")) {
 545                         if (parse_expiry_date(arg + 9, &cb.cmd.expire_total))
 546                                 die(_("'%s' is not a valid timestamp"), arg);
 547                         explicit_expiry |= EXPIRE_TOTAL;
 548                 }
 549                 else if (starts_with(arg, "--expire-unreachable=")) {
 550                         if (parse_expiry_date(arg + 21, &cb.cmd.expire_unreachable))
 551                                 die(_("'%s' is not a valid timestamp"), arg);
 552                         explicit_expiry |= EXPIRE_UNREACH;
 553                 }
 554                 else if (!strcmp(arg, "--stale-fix"))
 555                         cb.cmd.stalefix = 1;
 556                 else if (!strcmp(arg, "--rewrite"))
 557                         flags |= EXPIRE_REFLOGS_REWRITE;
 558                 else if (!strcmp(arg, "--updateref"))
 559                         flags |= EXPIRE_REFLOGS_UPDATE_REF;
 560                 else if (!strcmp(arg, "--all"))
 561                         do_all = 1;
 562                 else if (!strcmp(arg, "--verbose"))
 563                         flags |= EXPIRE_REFLOGS_VERBOSE;
 564                 else if (!strcmp(arg, "--")) {
 565                         i++;
 566                         break;
 567                 }
 568                 else if (arg[0] == '-')
 569                         usage(reflog_expire_usage);
 570                 else
 571                         break;
 572         }
 573
 574         /*
 575          * We can trust the commits and objects reachable from refs
 576          * even in older repository.  We cannot trust what's reachable
 577          * from reflog if the repository was pruned with older git.
 578          */
 579         if (cb.cmd.stalefix) {
 580                 init_revisions(&cb.cmd.revs, prefix);
 581                 if (flags & EXPIRE_REFLOGS_VERBOSE)
 582                         printf("Marking reachable objects...");
 583                 mark_reachable_objects(&cb.cmd.revs, 0, 0, NULL);
 584                 if (flags & EXPIRE_REFLOGS_VERBOSE)
 585                         putchar('\n');
 586         }
 587
 588         if (do_all) {
 589                 struct collect_reflog_cb collected;
 590                 int i;
 591
 592                 memset(&collected, 0, sizeof(collected));
 593                 for_each_reflog(collect_reflog, &collected);
 594                 for (i = 0; i < collected.nr; i++) {
 595                         struct collected_reflog *e = collected.e[i];
 596                         set_reflog_expiry_param(&cb.cmd, explicit_expiry, e->reflog);
 597                         status |= reflog_expire(e->reflog, e->sha1, flags,
 598                                                 reflog_expiry_prepare,
 599                                                 should_expire_reflog_ent,
 600                                                 reflog_expiry_cleanup,
 601                                                 &cb);
 602                         free(e);
 603                 }
 604                 free(collected.e);
 605         }
 606
 607         for (; i < argc; i++) {
 608                 char *ref;
 609                 unsigned char sha1[20];
 610                 if (!dwim_log(argv[i], strlen(argv[i]), sha1, &ref)) {
 611                         status |= error("%s points nowhere!", argv[i]);
 612                         continue;
 613                 }
 614                 set_reflog_expiry_param(&cb.cmd, explicit_expiry, ref);
 615                 status |= reflog_expire(ref, sha1, flags,
 616                                         reflog_expiry_prepare,
 617                                         should_expire_reflog_ent,
 618                                         reflog_expiry_cleanup,
 619                                         &cb);
 620         }
 621         return status;
 622 }
 623
 624 static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 625                 const char *email, unsigned long timestamp, int tz,
 626                 const char *message, void *cb_data)
 627 {
 628         struct expire_reflog_policy_cb *cb = cb_data;
 629         if (!cb->cmd.expire_total || timestamp < cb->cmd.expire_total)
 630                 cb->cmd.recno++;
 631         return 0;
 632 }
 633
 634 static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 635 {
 636         struct expire_reflog_policy_cb cb;
 637         int i, status = 0;
 638         unsigned int flags = 0;
 639
 640         memset(&cb, 0, sizeof(cb));
 641
 642         for (i = 1; i < argc; i++) {
 643                 const char *arg = argv[i];
 644                 if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 645                         flags |= EXPIRE_REFLOGS_DRY_RUN;
 646                 else if (!strcmp(arg, "--rewrite"))
 647                         flags |= EXPIRE_REFLOGS_REWRITE;
 648                 else if (!strcmp(arg, "--updateref"))
 649                         flags |= EXPIRE_REFLOGS_UPDATE_REF;
 650                 else if (!strcmp(arg, "--verbose"))
 651                         flags |= EXPIRE_REFLOGS_VERBOSE;
 652                 else if (!strcmp(arg, "--")) {
 653                         i++;
 654                         break;
 655                 }
 656                 else if (arg[0] == '-')
 657                         usage(reflog_delete_usage);
 658                 else
 659                         break;
 660         }
 661
 662         if (argc - i < 1)
 663                 return error("Nothing to delete?");
 664
 665         for ( ; i < argc; i++) {
 666                 const char *spec = strstr(argv[i], "@{");
 667                 unsigned char sha1[20];
 668                 char *ep, *ref;
 669                 int recno;
 670
 671                 if (!spec) {
 672                         status |= error("Not a reflog: %s", argv[i]);
 673                         continue;
 674                 }
 675
 676                 if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
 677                         status |= error("no reflog for '%s'", argv[i]);
 678                         continue;
 679                 }
 680
 681                 recno = strtoul(spec + 2, &ep, 10);
 682                 if (*ep == '}') {
 683                         cb.cmd.recno = -recno;
 684                         for_each_reflog_ent(ref, count_reflog_ent, &cb);
 685                 } else {
 686                         cb.cmd.expire_total = approxidate(spec + 2);
 687                         for_each_reflog_ent(ref, count_reflog_ent, &cb);
 688                         cb.cmd.expire_total = 0;
 689                 }
 690
 691                 status |= reflog_expire(ref, sha1, flags,
 692                                         reflog_expiry_prepare,
 693                                         should_expire_reflog_ent,
 694                                         reflog_expiry_cleanup,
 695                                         &cb);
 696                 free(ref);
 697         }
 698         return status;
 699 }
 700
 701 /*
 702  * main "reflog"
 703  */
 704
 705 static const char reflog_usage[] =
 706 "git reflog [ show | expire | delete ]";
 707
 708 int cmd_reflog(int argc, const char **argv, const char *prefix)
 709 {
 710         if (argc > 1 && !strcmp(argv[1], "-h"))
 711                 usage(reflog_usage);
 712
 713         /* With no command, we default to showing it. */
 714         if (argc < 2 || *argv[1] == '-')
 715                 return cmd_log_reflog(argc, argv, prefix);
 716
 717         if (!strcmp(argv[1], "show"))
 718                 return cmd_log_reflog(argc - 1, argv + 1, prefix);
 719
 720         if (!strcmp(argv[1], "expire"))
 721                 return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 722
 723         if (!strcmp(argv[1], "delete"))
 724                 return cmd_reflog_delete(argc - 1, argv + 1, prefix);
 725
 726         return cmd_log_reflog(argc, argv, prefix);
 727 }