| 1 | #define DISABLE_SIGN_COMPARE_WARNINGS |
| 2 | |
| 3 | #include "../git-compat-util.h" |
| 4 | #include "../abspath.h" |
| 5 | #include "../config.h" |
| 6 | #include "../copy.h" |
| 7 | #include "../environment.h" |
| 8 | #include "../gettext.h" |
| 9 | #include "../hash.h" |
| 10 | #include "../hex.h" |
| 11 | #include "../fsck.h" |
| 12 | #include "../refs.h" |
| 13 | #include "../repo-settings.h" |
| 14 | #include "refs-internal.h" |
| 15 | #include "ref-cache.h" |
| 16 | #include "packed-backend.h" |
| 17 | #include "../ident.h" |
| 18 | #include "../iterator.h" |
| 19 | #include "../dir-iterator.h" |
| 20 | #include "../lockfile.h" |
| 21 | #include "../path.h" |
| 22 | #include "../dir.h" |
| 23 | #include "../chdir-notify.h" |
| 24 | #include "../setup.h" |
| 25 | #include "../worktree.h" |
| 26 | #include "../wrapper.h" |
| 27 | #include "../write-or-die.h" |
| 28 | #include "../revision.h" |
| 29 | #include <wildmatch.h> |
| 30 | |
| 31 | /* So that we can drop `USE_THE_REPOSITORY_VARIABLE`. */ |
| 32 | extern int ignore_case; |
| 33 | |
| 34 | /* |
| 35 | * This backend uses the following flags in `ref_update::flags` for |
| 36 | * internal bookkeeping purposes. Their numerical values must not |
| 37 | * conflict with REF_NO_DEREF, REF_FORCE_CREATE_REFLOG, REF_HAVE_NEW, |
| 38 | * or REF_HAVE_OLD, which are also stored in `ref_update::flags`. |
| 39 | */ |
| 40 | |
| 41 | /* |
| 42 | * Used as a flag in ref_update::flags when a loose ref is being |
| 43 | * pruned. This flag must only be used when REF_NO_DEREF is set. |
| 44 | */ |
| 45 | #define REF_IS_PRUNING (1 << 4) |
| 46 | |
| 47 | /* |
| 48 | * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken |
| 49 | * refs (i.e., because the reference is about to be deleted anyway). |
| 50 | */ |
| 51 | #define REF_DELETING (1 << 5) |
| 52 | |
| 53 | /* |
| 54 | * Used as a flag in ref_update::flags when the lockfile needs to be |
| 55 | * committed. |
| 56 | */ |
| 57 | #define REF_NEEDS_COMMIT (1 << 6) |
| 58 | |
| 59 | /* |
| 60 | * Used as a flag in ref_update::flags when the ref_update was via an |
| 61 | * update to HEAD. |
| 62 | */ |
| 63 | #define REF_UPDATE_VIA_HEAD (1 << 8) |
| 64 | |
| 65 | /* |
| 66 | * Used as a flag in ref_update::flags when a reference has been |
| 67 | * deleted and the ref's parent directories may need cleanup. |
| 68 | */ |
| 69 | #define REF_DELETED_RMDIR (1 << 9) |
| 70 | |
| 71 | /* |
| 72 | * Used to indicate that the reflog-only update has been created via |
| 73 | * `split_head_update()`. |
| 74 | */ |
| 75 | #define REF_LOG_VIA_SPLIT (1 << 14) |
| 76 | |
| 77 | struct ref_lock { |
| 78 | char *ref_name; |
| 79 | struct lock_file lk; |
| 80 | struct object_id old_oid; |
| 81 | unsigned int count; /* track users of the lock (ref update + reflog updates) */ |
| 82 | }; |
| 83 | |
| 84 | struct files_ref_store { |
| 85 | struct ref_store base; |
| 86 | unsigned int store_flags; |
| 87 | |
| 88 | char *gitcommondir; |
| 89 | struct ref_cache *loose; |
| 90 | struct ref_store *packed_ref_store; |
| 91 | |
| 92 | /* |
| 93 | * Options used when writing references. These are parsed from the |
| 94 | * config lazily on first use via `files_ref_store_write_options()` so |
| 95 | * that we don't have to access the configuration when initializing the |
| 96 | * ref store. Do not access these fields directly, but use the accessor |
| 97 | * instead. |
| 98 | */ |
| 99 | struct files_ref_store_write_options { |
| 100 | enum log_refs_config log_all_ref_updates; |
| 101 | int prefer_symlink_refs; |
| 102 | bool initialized; |
| 103 | } write_opts_lazy_loaded; |
| 104 | }; |
| 105 | |
| 106 | static void clear_loose_ref_cache(struct files_ref_store *refs) |
| 107 | { |
| 108 | if (refs->loose) { |
| 109 | free_ref_cache(refs->loose); |
| 110 | refs->loose = NULL; |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | static void files_ref_store_reparent(const char *name UNUSED, |
| 115 | const char *old_cwd, |
| 116 | const char *new_cwd, |
| 117 | void *payload) |
| 118 | { |
| 119 | struct files_ref_store *refs = payload; |
| 120 | char *tmp; |
| 121 | |
| 122 | tmp = reparent_relative_path(old_cwd, new_cwd, refs->base.gitdir); |
| 123 | free(refs->base.gitdir); |
| 124 | refs->base.gitdir = tmp; |
| 125 | |
| 126 | tmp = reparent_relative_path(old_cwd, new_cwd, refs->gitcommondir); |
| 127 | free(refs->gitcommondir); |
| 128 | refs->gitcommondir = tmp; |
| 129 | } |
| 130 | |
| 131 | static int files_ref_store_config(const char *var, const char *value, |
| 132 | const struct config_context *ctx UNUSED, |
| 133 | void *payload) |
| 134 | { |
| 135 | struct files_ref_store_write_options *opts = payload; |
| 136 | |
| 137 | if (!strcmp(var, "core.prefersymlinkrefs")) { |
| 138 | opts->prefer_symlink_refs = git_config_bool(var, value); |
| 139 | } else if (!strcmp(var, "core.logallrefupdates")) { |
| 140 | opts->log_all_ref_updates = refs_parse_log_all_ref_updates_config(value); |
| 141 | } |
| 142 | |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | static const struct files_ref_store_write_options *files_ref_store_write_options(struct files_ref_store *refs) |
| 147 | { |
| 148 | struct files_ref_store_write_options *opts = &refs->write_opts_lazy_loaded; |
| 149 | |
| 150 | if (opts->initialized) |
| 151 | return opts; |
| 152 | |
| 153 | opts->log_all_ref_updates = LOG_REFS_UNSET; |
| 154 | repo_config(refs->base.repo, files_ref_store_config, opts); |
| 155 | |
| 156 | opts->initialized = true; |
| 157 | return opts; |
| 158 | } |
| 159 | |
| 160 | /* |
| 161 | * Create a new submodule ref cache and add it to the internal |
| 162 | * set of caches. |
| 163 | */ |
| 164 | static struct ref_store *files_ref_store_init(struct repository *repo, |
| 165 | const char *payload, |
| 166 | const char *gitdir, |
| 167 | const struct ref_store_init_options *opts) |
| 168 | { |
| 169 | struct files_ref_store *refs = xcalloc(1, sizeof(*refs)); |
| 170 | struct ref_store *ref_store = (struct ref_store *)refs; |
| 171 | struct strbuf ref_common_dir = STRBUF_INIT; |
| 172 | struct strbuf refdir = STRBUF_INIT; |
| 173 | bool is_worktree; |
| 174 | |
| 175 | refs_compute_filesystem_location(gitdir, payload, &is_worktree, &refdir, |
| 176 | &ref_common_dir); |
| 177 | |
| 178 | base_ref_store_init(ref_store, repo, refdir.buf, &refs_be_files); |
| 179 | |
| 180 | refs->gitcommondir = strbuf_detach(&ref_common_dir, NULL); |
| 181 | refs->packed_ref_store = |
| 182 | packed_ref_store_init(repo, NULL, refs->gitcommondir, opts); |
| 183 | refs->store_flags = opts->access_flags; |
| 184 | |
| 185 | chdir_notify_register(NULL, files_ref_store_reparent, refs); |
| 186 | |
| 187 | strbuf_release(&refdir); |
| 188 | |
| 189 | return ref_store; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * Die if refs is not the main ref store. caller is used in any |
| 194 | * necessary error messages. |
| 195 | */ |
| 196 | static void files_assert_main_repository(struct files_ref_store *refs, |
| 197 | const char *caller) |
| 198 | { |
| 199 | if (refs->store_flags & REF_STORE_MAIN) |
| 200 | return; |
| 201 | |
| 202 | BUG("operation %s only allowed for main ref store", caller); |
| 203 | } |
| 204 | |
| 205 | /* |
| 206 | * Downcast ref_store to files_ref_store. Die if ref_store is not a |
| 207 | * files_ref_store. required_flags is compared with ref_store's |
| 208 | * store_flags to ensure the ref_store has all required capabilities. |
| 209 | * "caller" is used in any necessary error messages. |
| 210 | */ |
| 211 | static struct files_ref_store *files_downcast(struct ref_store *ref_store, |
| 212 | unsigned int required_flags, |
| 213 | const char *caller) |
| 214 | { |
| 215 | struct files_ref_store *refs; |
| 216 | |
| 217 | if (ref_store->be != &refs_be_files) |
| 218 | BUG("ref_store is type \"%s\" not \"files\" in %s", |
| 219 | ref_store->be->name, caller); |
| 220 | |
| 221 | refs = (struct files_ref_store *)ref_store; |
| 222 | |
| 223 | if ((refs->store_flags & required_flags) != required_flags) |
| 224 | BUG("operation %s requires abilities 0x%x, but only have 0x%x", |
| 225 | caller, required_flags, refs->store_flags); |
| 226 | |
| 227 | return refs; |
| 228 | } |
| 229 | |
| 230 | static void files_ref_store_release(struct ref_store *ref_store) |
| 231 | { |
| 232 | struct files_ref_store *refs = files_downcast(ref_store, 0, "release"); |
| 233 | free_ref_cache(refs->loose); |
| 234 | free(refs->gitcommondir); |
| 235 | ref_store_release(refs->packed_ref_store); |
| 236 | free(refs->packed_ref_store); |
| 237 | chdir_notify_unregister(NULL, files_ref_store_reparent, refs); |
| 238 | } |
| 239 | |
| 240 | static void files_reflog_path(struct files_ref_store *refs, |
| 241 | struct strbuf *sb, |
| 242 | const char *refname) |
| 243 | { |
| 244 | const char *bare_refname; |
| 245 | const char *wtname; |
| 246 | int wtname_len; |
| 247 | enum ref_worktree_type wt_type = parse_worktree_ref( |
| 248 | refname, &wtname, &wtname_len, &bare_refname); |
| 249 | |
| 250 | switch (wt_type) { |
| 251 | case REF_WORKTREE_CURRENT: |
| 252 | strbuf_addf(sb, "%s/logs/%s", refs->base.gitdir, refname); |
| 253 | break; |
| 254 | case REF_WORKTREE_SHARED: |
| 255 | case REF_WORKTREE_MAIN: |
| 256 | strbuf_addf(sb, "%s/logs/%s", refs->gitcommondir, bare_refname); |
| 257 | break; |
| 258 | case REF_WORKTREE_OTHER: |
| 259 | strbuf_addf(sb, "%s/worktrees/%.*s/logs/%s", refs->gitcommondir, |
| 260 | wtname_len, wtname, bare_refname); |
| 261 | break; |
| 262 | default: |
| 263 | BUG("unknown ref type %d of ref %s", wt_type, refname); |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | static void files_ref_path(struct files_ref_store *refs, |
| 268 | struct strbuf *sb, |
| 269 | const char *refname) |
| 270 | { |
| 271 | const char *bare_refname; |
| 272 | const char *wtname; |
| 273 | int wtname_len; |
| 274 | enum ref_worktree_type wt_type = parse_worktree_ref( |
| 275 | refname, &wtname, &wtname_len, &bare_refname); |
| 276 | switch (wt_type) { |
| 277 | case REF_WORKTREE_CURRENT: |
| 278 | strbuf_addf(sb, "%s/%s", refs->base.gitdir, refname); |
| 279 | break; |
| 280 | case REF_WORKTREE_OTHER: |
| 281 | strbuf_addf(sb, "%s/worktrees/%.*s/%s", refs->gitcommondir, |
| 282 | wtname_len, wtname, bare_refname); |
| 283 | break; |
| 284 | case REF_WORKTREE_SHARED: |
| 285 | case REF_WORKTREE_MAIN: |
| 286 | strbuf_addf(sb, "%s/%s", refs->gitcommondir, bare_refname); |
| 287 | break; |
| 288 | default: |
| 289 | BUG("unknown ref type %d of ref %s", wt_type, refname); |
| 290 | } |
| 291 | } |
| 292 | |
| 293 | /* |
| 294 | * Manually add refs/bisect, refs/rewritten and refs/worktree, which, being |
| 295 | * per-worktree, might not appear in the directory listing for |
| 296 | * refs/ in the main repo. |
| 297 | */ |
| 298 | static void add_per_worktree_entries_to_dir(struct ref_dir *dir, const char *dirname) |
| 299 | { |
| 300 | const char *prefixes[] = { "refs/bisect/", "refs/worktree/", "refs/rewritten/" }; |
| 301 | int ip; |
| 302 | |
| 303 | if (strcmp(dirname, "refs/")) |
| 304 | return; |
| 305 | |
| 306 | for (ip = 0; ip < ARRAY_SIZE(prefixes); ip++) { |
| 307 | const char *prefix = prefixes[ip]; |
| 308 | int prefix_len = strlen(prefix); |
| 309 | struct ref_entry *child_entry; |
| 310 | int pos; |
| 311 | |
| 312 | pos = search_ref_dir(dir, prefix, prefix_len); |
| 313 | if (pos >= 0) |
| 314 | continue; |
| 315 | child_entry = create_dir_entry(dir->cache, prefix, prefix_len); |
| 316 | add_entry_to_dir(dir, child_entry); |
| 317 | } |
| 318 | } |
| 319 | |
| 320 | static void loose_fill_ref_dir_regular_file(struct files_ref_store *refs, |
| 321 | const char *refname, |
| 322 | struct ref_dir *dir) |
| 323 | { |
| 324 | struct object_id oid; |
| 325 | int flag; |
| 326 | const char *referent = refs_resolve_ref_unsafe(&refs->base, |
| 327 | refname, |
| 328 | RESOLVE_REF_READING, |
| 329 | &oid, &flag); |
| 330 | |
| 331 | if (!referent) { |
| 332 | oidclr(&oid, refs->base.repo->hash_algo); |
| 333 | flag |= REF_ISBROKEN; |
| 334 | } else if (is_null_oid(&oid)) { |
| 335 | /* |
| 336 | * It is so astronomically unlikely |
| 337 | * that null_oid is the OID of an |
| 338 | * actual object that we consider its |
| 339 | * appearance in a loose reference |
| 340 | * file to be repo corruption |
| 341 | * (probably due to a software bug). |
| 342 | */ |
| 343 | flag |= REF_ISBROKEN; |
| 344 | } |
| 345 | |
| 346 | if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { |
| 347 | if (!refname_is_safe(refname)) |
| 348 | die("loose refname is dangerous: %s", refname); |
| 349 | oidclr(&oid, refs->base.repo->hash_algo); |
| 350 | flag |= REF_BAD_NAME | REF_ISBROKEN; |
| 351 | } |
| 352 | |
| 353 | if (!(flag & REF_ISSYMREF)) |
| 354 | referent = NULL; |
| 355 | |
| 356 | add_entry_to_dir(dir, create_ref_entry(refname, referent, &oid, flag)); |
| 357 | } |
| 358 | |
| 359 | /* |
| 360 | * Read the loose references from the namespace dirname into dir |
| 361 | * (without recursing). dirname must end with '/'. dir must be the |
| 362 | * directory entry corresponding to dirname. |
| 363 | */ |
| 364 | static void loose_fill_ref_dir(struct ref_store *ref_store, |
| 365 | struct ref_dir *dir, const char *dirname) |
| 366 | { |
| 367 | struct files_ref_store *refs = |
| 368 | files_downcast(ref_store, REF_STORE_READ, "fill_ref_dir"); |
| 369 | DIR *d; |
| 370 | struct dirent *de; |
| 371 | int dirnamelen = strlen(dirname); |
| 372 | struct strbuf refname; |
| 373 | struct strbuf path = STRBUF_INIT; |
| 374 | |
| 375 | files_ref_path(refs, &path, dirname); |
| 376 | |
| 377 | d = opendir(path.buf); |
| 378 | if (!d) { |
| 379 | strbuf_release(&path); |
| 380 | return; |
| 381 | } |
| 382 | |
| 383 | strbuf_init(&refname, dirnamelen + 257); |
| 384 | strbuf_add(&refname, dirname, dirnamelen); |
| 385 | |
| 386 | while ((de = readdir(d)) != NULL) { |
| 387 | unsigned char dtype; |
| 388 | |
| 389 | if (de->d_name[0] == '.') |
| 390 | continue; |
| 391 | if (ends_with(de->d_name, ".lock")) |
| 392 | continue; |
| 393 | strbuf_addstr(&refname, de->d_name); |
| 394 | |
| 395 | dtype = get_dtype(de, &path, 1); |
| 396 | if (dtype == DT_DIR) { |
| 397 | strbuf_addch(&refname, '/'); |
| 398 | add_entry_to_dir(dir, |
| 399 | create_dir_entry(dir->cache, refname.buf, |
| 400 | refname.len)); |
| 401 | } else if (dtype == DT_REG) { |
| 402 | loose_fill_ref_dir_regular_file(refs, refname.buf, dir); |
| 403 | } |
| 404 | strbuf_setlen(&refname, dirnamelen); |
| 405 | } |
| 406 | strbuf_release(&refname); |
| 407 | strbuf_release(&path); |
| 408 | closedir(d); |
| 409 | |
| 410 | add_per_worktree_entries_to_dir(dir, dirname); |
| 411 | } |
| 412 | |
| 413 | static int for_each_root_ref(struct files_ref_store *refs, |
| 414 | int (*cb)(const char *refname, void *cb_data), |
| 415 | void *cb_data) |
| 416 | { |
| 417 | struct strbuf path = STRBUF_INIT, refname = STRBUF_INIT; |
| 418 | struct dirent *de; |
| 419 | int ret; |
| 420 | DIR *d; |
| 421 | |
| 422 | files_ref_path(refs, &path, ""); |
| 423 | |
| 424 | d = opendir(path.buf); |
| 425 | if (!d) { |
| 426 | strbuf_release(&path); |
| 427 | return -1; |
| 428 | } |
| 429 | |
| 430 | while ((de = readdir(d)) != NULL) { |
| 431 | unsigned char dtype; |
| 432 | |
| 433 | if (de->d_name[0] == '.') |
| 434 | continue; |
| 435 | if (ends_with(de->d_name, ".lock")) |
| 436 | continue; |
| 437 | |
| 438 | strbuf_reset(&refname); |
| 439 | strbuf_addstr(&refname, de->d_name); |
| 440 | |
| 441 | dtype = get_dtype(de, &path, 1); |
| 442 | if (dtype == DT_REG && is_root_ref(de->d_name)) { |
| 443 | ret = cb(refname.buf, cb_data); |
| 444 | if (ret) |
| 445 | goto done; |
| 446 | } |
| 447 | } |
| 448 | |
| 449 | ret = 0; |
| 450 | |
| 451 | done: |
| 452 | strbuf_release(&refname); |
| 453 | strbuf_release(&path); |
| 454 | closedir(d); |
| 455 | return ret; |
| 456 | } |
| 457 | |
| 458 | struct fill_root_ref_data { |
| 459 | struct files_ref_store *refs; |
| 460 | struct ref_dir *dir; |
| 461 | }; |
| 462 | |
| 463 | static int fill_root_ref(const char *refname, void *cb_data) |
| 464 | { |
| 465 | struct fill_root_ref_data *data = cb_data; |
| 466 | loose_fill_ref_dir_regular_file(data->refs, refname, data->dir); |
| 467 | return 0; |
| 468 | } |
| 469 | |
| 470 | /* |
| 471 | * Add root refs to the ref dir by parsing the directory for any files which |
| 472 | * follow the root ref syntax. |
| 473 | */ |
| 474 | static void add_root_refs(struct files_ref_store *refs, |
| 475 | struct ref_dir *dir) |
| 476 | { |
| 477 | struct fill_root_ref_data data = { |
| 478 | .refs = refs, |
| 479 | .dir = dir, |
| 480 | }; |
| 481 | |
| 482 | for_each_root_ref(refs, fill_root_ref, &data); |
| 483 | } |
| 484 | |
| 485 | static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs, |
| 486 | unsigned int flags) |
| 487 | { |
| 488 | if (!refs->loose) { |
| 489 | struct ref_dir *dir; |
| 490 | |
| 491 | /* |
| 492 | * Mark the top-level directory complete because we |
| 493 | * are about to read the only subdirectory that can |
| 494 | * hold references: |
| 495 | */ |
| 496 | refs->loose = create_ref_cache(&refs->base, loose_fill_ref_dir); |
| 497 | |
| 498 | /* We're going to fill the top level ourselves: */ |
| 499 | refs->loose->root->flag &= ~REF_INCOMPLETE; |
| 500 | |
| 501 | dir = get_ref_dir(refs->loose->root); |
| 502 | |
| 503 | if (flags & REFS_FOR_EACH_INCLUDE_ROOT_REFS) |
| 504 | add_root_refs(refs, dir); |
| 505 | |
| 506 | /* |
| 507 | * Add an incomplete entry for "refs/" (to be filled |
| 508 | * lazily): |
| 509 | */ |
| 510 | add_entry_to_dir(dir, create_dir_entry(refs->loose, "refs/", 5)); |
| 511 | } |
| 512 | return refs->loose; |
| 513 | } |
| 514 | |
| 515 | static int read_ref_internal(struct ref_store *ref_store, const char *refname, |
| 516 | struct object_id *oid, struct strbuf *referent, |
| 517 | unsigned int *type, int *failure_errno, int skip_packed_refs) |
| 518 | { |
| 519 | struct files_ref_store *refs = |
| 520 | files_downcast(ref_store, REF_STORE_READ, "read_raw_ref"); |
| 521 | struct strbuf sb_contents = STRBUF_INIT; |
| 522 | struct strbuf sb_path = STRBUF_INIT; |
| 523 | const char *path; |
| 524 | const char *buf; |
| 525 | struct stat st; |
| 526 | int fd; |
| 527 | int ret = -1; |
| 528 | int remaining_retries = 3; |
| 529 | int myerr = 0; |
| 530 | |
| 531 | *type = 0; |
| 532 | strbuf_reset(&sb_path); |
| 533 | |
| 534 | files_ref_path(refs, &sb_path, refname); |
| 535 | |
| 536 | path = sb_path.buf; |
| 537 | |
| 538 | stat_ref: |
| 539 | /* |
| 540 | * We might have to loop back here to avoid a race |
| 541 | * condition: first we lstat() the file, then we try |
| 542 | * to read it as a link or as a file. But if somebody |
| 543 | * changes the type of the file (file <-> directory |
| 544 | * <-> symlink) between the lstat() and reading, then |
| 545 | * we don't want to report that as an error but rather |
| 546 | * try again starting with the lstat(). |
| 547 | * |
| 548 | * We'll keep a count of the retries, though, just to avoid |
| 549 | * any confusing situation sending us into an infinite loop. |
| 550 | */ |
| 551 | |
| 552 | if (remaining_retries-- <= 0) |
| 553 | goto out; |
| 554 | |
| 555 | if (lstat(path, &st) < 0) { |
| 556 | int ignore_errno; |
| 557 | myerr = errno; |
| 558 | if (myerr != ENOENT || skip_packed_refs) |
| 559 | goto out; |
| 560 | if (refs_read_raw_ref(refs->packed_ref_store, refname, oid, |
| 561 | referent, type, &ignore_errno)) { |
| 562 | myerr = ENOENT; |
| 563 | goto out; |
| 564 | } |
| 565 | ret = 0; |
| 566 | goto out; |
| 567 | } |
| 568 | |
| 569 | /* Follow "normalized" - ie "refs/.." symlinks by hand */ |
| 570 | if (S_ISLNK(st.st_mode)) { |
| 571 | strbuf_reset(&sb_contents); |
| 572 | if (strbuf_readlink(&sb_contents, path, st.st_size) < 0) { |
| 573 | myerr = errno; |
| 574 | if (myerr == ENOENT || myerr == EINVAL) |
| 575 | /* inconsistent with lstat; retry */ |
| 576 | goto stat_ref; |
| 577 | else |
| 578 | goto out; |
| 579 | } |
| 580 | if (starts_with(sb_contents.buf, "refs/") && |
| 581 | !check_refname_format(sb_contents.buf, 0)) { |
| 582 | strbuf_swap(&sb_contents, referent); |
| 583 | *type |= REF_ISSYMREF; |
| 584 | ret = 0; |
| 585 | goto out; |
| 586 | } |
| 587 | /* |
| 588 | * It doesn't look like a refname; fall through to just |
| 589 | * treating it like a non-symlink, and reading whatever it |
| 590 | * points to. |
| 591 | */ |
| 592 | } |
| 593 | |
| 594 | /* Is it a directory? */ |
| 595 | if (S_ISDIR(st.st_mode)) { |
| 596 | int ignore_errno; |
| 597 | /* |
| 598 | * Even though there is a directory where the loose |
| 599 | * ref is supposed to be, there could still be a |
| 600 | * packed ref: |
| 601 | */ |
| 602 | if (skip_packed_refs || |
| 603 | refs_read_raw_ref(refs->packed_ref_store, refname, oid, |
| 604 | referent, type, &ignore_errno)) { |
| 605 | myerr = EISDIR; |
| 606 | goto out; |
| 607 | } |
| 608 | ret = 0; |
| 609 | goto out; |
| 610 | } |
| 611 | |
| 612 | /* |
| 613 | * Anything else, just open it and try to use it as |
| 614 | * a ref |
| 615 | */ |
| 616 | fd = open(path, O_RDONLY); |
| 617 | if (fd < 0) { |
| 618 | myerr = errno; |
| 619 | if (myerr == ENOENT && !S_ISLNK(st.st_mode)) |
| 620 | /* inconsistent with lstat; retry */ |
| 621 | goto stat_ref; |
| 622 | else |
| 623 | goto out; |
| 624 | } |
| 625 | strbuf_reset(&sb_contents); |
| 626 | if (strbuf_read(&sb_contents, fd, 256) < 0) { |
| 627 | myerr = errno; |
| 628 | close(fd); |
| 629 | goto out; |
| 630 | } |
| 631 | close(fd); |
| 632 | strbuf_rtrim(&sb_contents); |
| 633 | buf = sb_contents.buf; |
| 634 | |
| 635 | ret = parse_loose_ref_contents(ref_store->repo->hash_algo, buf, |
| 636 | oid, referent, type, NULL, &myerr); |
| 637 | |
| 638 | out: |
| 639 | if (ret && !myerr) |
| 640 | BUG("returning non-zero %d, should have set myerr!", ret); |
| 641 | *failure_errno = myerr; |
| 642 | |
| 643 | strbuf_release(&sb_path); |
| 644 | strbuf_release(&sb_contents); |
| 645 | errno = 0; |
| 646 | return ret; |
| 647 | } |
| 648 | |
| 649 | static int files_read_raw_ref(struct ref_store *ref_store, const char *refname, |
| 650 | struct object_id *oid, struct strbuf *referent, |
| 651 | unsigned int *type, int *failure_errno) |
| 652 | { |
| 653 | return read_ref_internal(ref_store, refname, oid, referent, type, failure_errno, 0); |
| 654 | } |
| 655 | |
| 656 | static int files_read_symbolic_ref(struct ref_store *ref_store, const char *refname, |
| 657 | struct strbuf *referent) |
| 658 | { |
| 659 | struct object_id oid; |
| 660 | int failure_errno, ret; |
| 661 | unsigned int type; |
| 662 | |
| 663 | ret = read_ref_internal(ref_store, refname, &oid, referent, &type, &failure_errno, 1); |
| 664 | if (!ret && !(type & REF_ISSYMREF)) |
| 665 | return NOT_A_SYMREF; |
| 666 | return ret; |
| 667 | } |
| 668 | |
| 669 | int parse_loose_ref_contents(const struct git_hash_algo *algop, |
| 670 | const char *buf, struct object_id *oid, |
| 671 | struct strbuf *referent, unsigned int *type, |
| 672 | const char **trailing, int *failure_errno) |
| 673 | { |
| 674 | const char *p; |
| 675 | if (skip_prefix(buf, "ref:", &buf)) { |
| 676 | while (isspace(*buf)) |
| 677 | buf++; |
| 678 | |
| 679 | strbuf_reset(referent); |
| 680 | strbuf_addstr(referent, buf); |
| 681 | *type |= REF_ISSYMREF; |
| 682 | return 0; |
| 683 | } |
| 684 | |
| 685 | /* |
| 686 | * FETCH_HEAD has additional data after the sha. |
| 687 | */ |
| 688 | if (parse_oid_hex_algop(buf, oid, &p, algop) || |
| 689 | (*p != '\0' && !isspace(*p))) { |
| 690 | *type |= REF_ISBROKEN; |
| 691 | *failure_errno = EINVAL; |
| 692 | return -1; |
| 693 | } |
| 694 | |
| 695 | if (trailing) |
| 696 | *trailing = p; |
| 697 | |
| 698 | return 0; |
| 699 | } |
| 700 | |
| 701 | static void unlock_ref(struct ref_lock *lock) |
| 702 | { |
| 703 | lock->count--; |
| 704 | if (!lock->count) { |
| 705 | rollback_lock_file(&lock->lk); |
| 706 | free(lock->ref_name); |
| 707 | free(lock); |
| 708 | } |
| 709 | } |
| 710 | |
| 711 | /* |
| 712 | * Check if the transaction has another update with a case-insensitive refname |
| 713 | * match. |
| 714 | * |
| 715 | * If the update is part of the transaction, we only check up to that index. |
| 716 | * Further updates are expected to call this function to match previous indices. |
| 717 | */ |
| 718 | static bool transaction_has_case_conflicting_update(struct ref_transaction *transaction, |
| 719 | struct ref_update *update) |
| 720 | { |
| 721 | for (size_t i = 0; i < transaction->nr; i++) { |
| 722 | if (transaction->updates[i] == update) |
| 723 | break; |
| 724 | |
| 725 | if (!strcasecmp(transaction->updates[i]->refname, update->refname)) |
| 726 | return true; |
| 727 | } |
| 728 | return false; |
| 729 | } |
| 730 | |
| 731 | /* |
| 732 | * Lock refname, without following symrefs, and set *lock_p to point |
| 733 | * at a newly-allocated lock object. Fill in lock->old_oid, referent, |
| 734 | * and type similarly to read_raw_ref(). |
| 735 | * |
| 736 | * The caller must verify that refname is a "safe" reference name (in |
| 737 | * the sense of refname_is_safe()) before calling this function. |
| 738 | * |
| 739 | * If the reference doesn't already exist, verify that refname doesn't |
| 740 | * have a D/F conflict with any existing references. extras and skip |
| 741 | * are passed to refs_verify_refname_available() for this check. |
| 742 | * |
| 743 | * If mustexist is not set and the reference is not found or is |
| 744 | * broken, lock the reference anyway but clear old_oid. |
| 745 | * |
| 746 | * Return 0 on success. On failure, write an error message to err and |
| 747 | * return REF_TRANSACTION_ERROR_NAME_CONFLICT or REF_TRANSACTION_ERROR_GENERIC. |
| 748 | * |
| 749 | * Implementation note: This function is basically |
| 750 | * |
| 751 | * lock reference |
| 752 | * read_raw_ref() |
| 753 | * |
| 754 | * but it includes a lot more code to |
| 755 | * - Deal with possible races with other processes |
| 756 | * - Avoid calling refs_verify_refname_available() when it can be |
| 757 | * avoided, namely if we were successfully able to read the ref |
| 758 | * - Generate informative error messages in the case of failure |
| 759 | */ |
| 760 | static enum ref_transaction_error lock_raw_ref(struct files_ref_store *refs, |
| 761 | struct ref_transaction *transaction, |
| 762 | size_t update_idx, |
| 763 | int mustexist, |
| 764 | struct string_list *refnames_to_check, |
| 765 | struct ref_lock **lock_p, |
| 766 | struct strbuf *referent, |
| 767 | struct strbuf *err) |
| 768 | { |
| 769 | enum ref_transaction_error ret = REF_TRANSACTION_ERROR_GENERIC; |
| 770 | struct ref_update *update = transaction->updates[update_idx]; |
| 771 | const struct string_list *extras = &transaction->refnames; |
| 772 | const char *refname = update->refname; |
| 773 | unsigned int *type = &update->type; |
| 774 | struct ref_lock *lock; |
| 775 | struct strbuf ref_file = STRBUF_INIT; |
| 776 | int attempts_remaining = 3; |
| 777 | int failure_errno; |
| 778 | |
| 779 | assert(err); |
| 780 | files_assert_main_repository(refs, "lock_raw_ref"); |
| 781 | |
| 782 | *type = 0; |
| 783 | |
| 784 | /* First lock the file so it can't change out from under us. */ |
| 785 | |
| 786 | *lock_p = CALLOC_ARRAY(lock, 1); |
| 787 | |
| 788 | lock->ref_name = xstrdup(refname); |
| 789 | lock->count = 1; |
| 790 | files_ref_path(refs, &ref_file, refname); |
| 791 | |
| 792 | retry: |
| 793 | switch (safe_create_leading_directories(refs->base.repo, ref_file.buf)) { |
| 794 | case SCLD_OK: |
| 795 | break; /* success */ |
| 796 | case SCLD_EXISTS: |
| 797 | /* |
| 798 | * Suppose refname is "refs/foo/bar". We just failed |
| 799 | * to create the containing directory, "refs/foo", |
| 800 | * because there was a non-directory in the way. This |
| 801 | * indicates a D/F conflict, probably because of |
| 802 | * another reference such as "refs/foo". There is no |
| 803 | * reason to expect this error to be transitory. |
| 804 | */ |
| 805 | if (refs_verify_refname_available(&refs->base, refname, |
| 806 | extras, NULL, 0, err)) { |
| 807 | if (mustexist) { |
| 808 | /* |
| 809 | * To the user the relevant error is |
| 810 | * that the "mustexist" reference is |
| 811 | * missing: |
| 812 | */ |
| 813 | strbuf_reset(err); |
| 814 | strbuf_addf(err, "unable to resolve reference '%s'", |
| 815 | refname); |
| 816 | ret = REF_TRANSACTION_ERROR_NONEXISTENT_REF; |
| 817 | } else { |
| 818 | /* |
| 819 | * The error message set by |
| 820 | * refs_verify_refname_available() is |
| 821 | * OK. |
| 822 | */ |
| 823 | ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; |
| 824 | } |
| 825 | } else { |
| 826 | /* |
| 827 | * The file that is in the way isn't a loose |
| 828 | * reference. Report it as a low-level |
| 829 | * failure. |
| 830 | */ |
| 831 | strbuf_addf(err, "unable to create lock file %s.lock; " |
| 832 | "non-directory in the way", |
| 833 | ref_file.buf); |
| 834 | } |
| 835 | goto error_return; |
| 836 | case SCLD_VANISHED: |
| 837 | /* Maybe another process was tidying up. Try again. */ |
| 838 | if (--attempts_remaining > 0) |
| 839 | goto retry; |
| 840 | /* fall through */ |
| 841 | default: |
| 842 | strbuf_addf(err, "unable to create directory for %s", |
| 843 | ref_file.buf); |
| 844 | goto error_return; |
| 845 | } |
| 846 | |
| 847 | if (repo_hold_lock_file_for_update_timeout(refs->base.repo, |
| 848 | &lock->lk, ref_file.buf, LOCK_NO_DEREF, |
| 849 | get_files_ref_lock_timeout_ms(transaction->ref_store->repo)) < 0) { |
| 850 | int myerr = errno; |
| 851 | errno = 0; |
| 852 | if (myerr == ENOENT && --attempts_remaining > 0) { |
| 853 | /* |
| 854 | * Maybe somebody just deleted one of the |
| 855 | * directories leading to ref_file. Try |
| 856 | * again: |
| 857 | */ |
| 858 | goto retry; |
| 859 | } else { |
| 860 | unable_to_lock_message(ref_file.buf, myerr, err); |
| 861 | if (myerr == EEXIST) { |
| 862 | if (repo_ignore_case(refs->base.repo) && |
| 863 | transaction_has_case_conflicting_update(transaction, update)) { |
| 864 | /* |
| 865 | * In case-insensitive filesystems, ensure that conflicts within a |
| 866 | * given transaction are handled. Pre-existing refs on a |
| 867 | * case-insensitive system will be overridden without any issue. |
| 868 | */ |
| 869 | ret = REF_TRANSACTION_ERROR_CASE_CONFLICT; |
| 870 | } else { |
| 871 | /* |
| 872 | * Pre-existing case-conflicting reference locks should also be |
| 873 | * specially categorized to avoid failing all batched updates. |
| 874 | */ |
| 875 | ret = REF_TRANSACTION_ERROR_CREATE_EXISTS; |
| 876 | } |
| 877 | } |
| 878 | |
| 879 | goto error_return; |
| 880 | } |
| 881 | } |
| 882 | |
| 883 | /* |
| 884 | * Now we hold the lock and can read the reference without |
| 885 | * fear that its value will change. |
| 886 | */ |
| 887 | |
| 888 | if (files_read_raw_ref(&refs->base, refname, &lock->old_oid, referent, |
| 889 | type, &failure_errno)) { |
| 890 | struct string_list_item *item; |
| 891 | |
| 892 | if (failure_errno == ENOENT) { |
| 893 | if (mustexist) { |
| 894 | /* Garden variety missing reference. */ |
| 895 | strbuf_addf(err, "unable to resolve reference '%s'", |
| 896 | refname); |
| 897 | ret = REF_TRANSACTION_ERROR_NONEXISTENT_REF; |
| 898 | goto error_return; |
| 899 | } else { |
| 900 | /* |
| 901 | * Reference is missing, but that's OK. We |
| 902 | * know that there is not a conflict with |
| 903 | * another loose reference because |
| 904 | * (supposing that we are trying to lock |
| 905 | * reference "refs/foo/bar"): |
| 906 | * |
| 907 | * - We were successfully able to create |
| 908 | * the lockfile refs/foo/bar.lock, so we |
| 909 | * know there cannot be a loose reference |
| 910 | * named "refs/foo". |
| 911 | * |
| 912 | * - We got ENOENT and not EISDIR, so we |
| 913 | * know that there cannot be a loose |
| 914 | * reference named "refs/foo/bar/baz". |
| 915 | */ |
| 916 | } |
| 917 | } else if (failure_errno == EISDIR) { |
| 918 | /* |
| 919 | * There is a directory in the way. It might have |
| 920 | * contained references that have been deleted. If |
| 921 | * we don't require that the reference already |
| 922 | * exists, try to remove the directory so that it |
| 923 | * doesn't cause trouble when we want to rename the |
| 924 | * lockfile into place later. |
| 925 | */ |
| 926 | if (mustexist) { |
| 927 | /* Garden variety missing reference. */ |
| 928 | strbuf_addf(err, "unable to resolve reference '%s'", |
| 929 | refname); |
| 930 | ret = REF_TRANSACTION_ERROR_NONEXISTENT_REF; |
| 931 | goto error_return; |
| 932 | } else if (remove_dir_recursively(&ref_file, |
| 933 | REMOVE_DIR_EMPTY_ONLY)) { |
| 934 | ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; |
| 935 | if (refs_verify_refname_available( |
| 936 | &refs->base, refname, |
| 937 | extras, NULL, 0, err)) { |
| 938 | /* |
| 939 | * The error message set by |
| 940 | * verify_refname_available() is OK. |
| 941 | */ |
| 942 | goto error_return; |
| 943 | } else { |
| 944 | /* |
| 945 | * Directory conflicts can occur if there |
| 946 | * is an existing lock file in the directory |
| 947 | * or if the filesystem is case-insensitive |
| 948 | * and the directory contains a valid reference |
| 949 | * but conflicts with the update. |
| 950 | */ |
| 951 | strbuf_addf(err, "there is a non-empty directory '%s' " |
| 952 | "blocking reference '%s'", |
| 953 | ref_file.buf, refname); |
| 954 | goto error_return; |
| 955 | } |
| 956 | } |
| 957 | } else if (failure_errno == EINVAL && (*type & REF_ISBROKEN)) { |
| 958 | strbuf_addf(err, "unable to resolve reference '%s': " |
| 959 | "reference broken", refname); |
| 960 | goto error_return; |
| 961 | } else { |
| 962 | strbuf_addf(err, "unable to resolve reference '%s': %s", |
| 963 | refname, strerror(failure_errno)); |
| 964 | goto error_return; |
| 965 | } |
| 966 | |
| 967 | /* |
| 968 | * If the ref did not exist and we are creating it, we have to |
| 969 | * make sure there is no existing packed ref that conflicts |
| 970 | * with refname. This check is deferred so that we can batch it. |
| 971 | * |
| 972 | * For case-insensitive filesystems, we should also check for F/D |
| 973 | * conflicts between 'foo' and 'Foo/bar'. So let's lowercase |
| 974 | * the refname. |
| 975 | */ |
| 976 | if (repo_ignore_case(refs->base.repo)) { |
| 977 | struct strbuf lower = STRBUF_INIT; |
| 978 | |
| 979 | strbuf_addstr(&lower, refname); |
| 980 | strbuf_tolower(&lower); |
| 981 | |
| 982 | item = string_list_append_nodup(refnames_to_check, |
| 983 | strbuf_detach(&lower, NULL)); |
| 984 | } else { |
| 985 | item = string_list_append(refnames_to_check, refname); |
| 986 | } |
| 987 | |
| 988 | item->util = xmalloc(sizeof(update_idx)); |
| 989 | memcpy(item->util, &update_idx, sizeof(update_idx)); |
| 990 | } |
| 991 | |
| 992 | ret = 0; |
| 993 | goto out; |
| 994 | |
| 995 | error_return: |
| 996 | unlock_ref(lock); |
| 997 | *lock_p = NULL; |
| 998 | |
| 999 | out: |
| 1000 | strbuf_release(&ref_file); |
| 1001 | return ret; |
| 1002 | } |
| 1003 | |
| 1004 | struct files_ref_iterator { |
| 1005 | struct ref_iterator base; |
| 1006 | |
| 1007 | struct ref_iterator *iter0; |
| 1008 | struct repository *repo; |
| 1009 | unsigned int flags; |
| 1010 | }; |
| 1011 | |
| 1012 | static int files_ref_iterator_advance(struct ref_iterator *ref_iterator) |
| 1013 | { |
| 1014 | struct files_ref_iterator *iter = |
| 1015 | (struct files_ref_iterator *)ref_iterator; |
| 1016 | int ok; |
| 1017 | |
| 1018 | while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) { |
| 1019 | if (iter->flags & REFS_FOR_EACH_PER_WORKTREE_ONLY && |
| 1020 | parse_worktree_ref(iter->iter0->ref.name, NULL, NULL, |
| 1021 | NULL) != REF_WORKTREE_CURRENT) |
| 1022 | continue; |
| 1023 | |
| 1024 | if ((iter->flags & REFS_FOR_EACH_OMIT_DANGLING_SYMREFS) && |
| 1025 | (iter->iter0->ref.flags & REF_ISSYMREF) && |
| 1026 | (iter->iter0->ref.flags & REF_ISBROKEN)) |
| 1027 | continue; |
| 1028 | |
| 1029 | if (!(iter->flags & REFS_FOR_EACH_INCLUDE_BROKEN) && |
| 1030 | !ref_resolves_to_object(iter->iter0->ref.name, |
| 1031 | iter->repo, |
| 1032 | iter->iter0->ref.oid, |
| 1033 | iter->iter0->ref.flags)) |
| 1034 | continue; |
| 1035 | |
| 1036 | iter->base.ref = iter->iter0->ref; |
| 1037 | |
| 1038 | return ITER_OK; |
| 1039 | } |
| 1040 | |
| 1041 | return ok; |
| 1042 | } |
| 1043 | |
| 1044 | static int files_ref_iterator_seek(struct ref_iterator *ref_iterator, |
| 1045 | const char *refname, unsigned int flags) |
| 1046 | { |
| 1047 | struct files_ref_iterator *iter = |
| 1048 | (struct files_ref_iterator *)ref_iterator; |
| 1049 | return ref_iterator_seek(iter->iter0, refname, flags); |
| 1050 | } |
| 1051 | |
| 1052 | static void files_ref_iterator_release(struct ref_iterator *ref_iterator) |
| 1053 | { |
| 1054 | struct files_ref_iterator *iter = |
| 1055 | (struct files_ref_iterator *)ref_iterator; |
| 1056 | ref_iterator_free(iter->iter0); |
| 1057 | } |
| 1058 | |
| 1059 | static struct ref_iterator_vtable files_ref_iterator_vtable = { |
| 1060 | .advance = files_ref_iterator_advance, |
| 1061 | .seek = files_ref_iterator_seek, |
| 1062 | .release = files_ref_iterator_release, |
| 1063 | }; |
| 1064 | |
| 1065 | static struct ref_iterator *files_ref_iterator_begin( |
| 1066 | struct ref_store *ref_store, |
| 1067 | const char *prefix, const char **exclude_patterns, |
| 1068 | unsigned int flags) |
| 1069 | { |
| 1070 | struct files_ref_store *refs; |
| 1071 | struct ref_iterator *loose_iter, *packed_iter, *overlay_iter; |
| 1072 | struct files_ref_iterator *iter; |
| 1073 | struct ref_iterator *ref_iterator; |
| 1074 | unsigned int required_flags = REF_STORE_READ; |
| 1075 | |
| 1076 | if (!(flags & REFS_FOR_EACH_INCLUDE_BROKEN)) |
| 1077 | required_flags |= REF_STORE_ODB; |
| 1078 | |
| 1079 | refs = files_downcast(ref_store, required_flags, "ref_iterator_begin"); |
| 1080 | |
| 1081 | /* |
| 1082 | * We must make sure that all loose refs are read before |
| 1083 | * accessing the packed-refs file; this avoids a race |
| 1084 | * condition if loose refs are migrated to the packed-refs |
| 1085 | * file by a simultaneous process, but our in-memory view is |
| 1086 | * from before the migration. We ensure this as follows: |
| 1087 | * First, we call start the loose refs iteration with its |
| 1088 | * `prime_ref` argument set to true. This causes the loose |
| 1089 | * references in the subtree to be pre-read into the cache. |
| 1090 | * (If they've already been read, that's OK; we only need to |
| 1091 | * guarantee that they're read before the packed refs, not |
| 1092 | * *how much* before.) After that, we call |
| 1093 | * packed_ref_iterator_begin(), which internally checks |
| 1094 | * whether the packed-ref cache is up to date with what is on |
| 1095 | * disk, and re-reads it if not. |
| 1096 | */ |
| 1097 | |
| 1098 | loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, flags), |
| 1099 | prefix, ref_store->repo, 1); |
| 1100 | |
| 1101 | /* |
| 1102 | * The packed-refs file might contain broken references, for |
| 1103 | * example an old version of a reference that points at an |
| 1104 | * object that has since been garbage-collected. This is OK as |
| 1105 | * long as there is a corresponding loose reference that |
| 1106 | * overrides it, and we don't want to emit an error message in |
| 1107 | * this case. So ask the packed_ref_store for all of its |
| 1108 | * references, and (if needed) do our own check for broken |
| 1109 | * ones in files_ref_iterator_advance(), after we have merged |
| 1110 | * the packed and loose references. |
| 1111 | */ |
| 1112 | packed_iter = refs_ref_iterator_begin( |
| 1113 | refs->packed_ref_store, prefix, exclude_patterns, 0, |
| 1114 | REFS_FOR_EACH_INCLUDE_BROKEN); |
| 1115 | |
| 1116 | overlay_iter = overlay_ref_iterator_begin(loose_iter, packed_iter); |
| 1117 | |
| 1118 | CALLOC_ARRAY(iter, 1); |
| 1119 | ref_iterator = &iter->base; |
| 1120 | base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable); |
| 1121 | iter->iter0 = overlay_iter; |
| 1122 | iter->repo = ref_store->repo; |
| 1123 | iter->flags = flags; |
| 1124 | |
| 1125 | return ref_iterator; |
| 1126 | } |
| 1127 | |
| 1128 | /* |
| 1129 | * Callback function for raceproof_create_file(). This function is |
| 1130 | * expected to do something that makes dirname(path) permanent despite |
| 1131 | * the fact that other processes might be cleaning up empty |
| 1132 | * directories at the same time. Usually it will create a file named |
| 1133 | * path, but alternatively it could create another file in that |
| 1134 | * directory, or even chdir() into that directory. The function should |
| 1135 | * return 0 if the action was completed successfully. On error, it |
| 1136 | * should return a nonzero result and set errno. |
| 1137 | * raceproof_create_file() treats two errno values specially: |
| 1138 | * |
| 1139 | * - ENOENT -- dirname(path) does not exist. In this case, |
| 1140 | * raceproof_create_file() tries creating dirname(path) |
| 1141 | * (and any parent directories, if necessary) and calls |
| 1142 | * the function again. |
| 1143 | * |
| 1144 | * - EISDIR -- the file already exists and is a directory. In this |
| 1145 | * case, raceproof_create_file() removes the directory if |
| 1146 | * it is empty (and recursively any empty directories that |
| 1147 | * it contains) and calls the function again. |
| 1148 | * |
| 1149 | * Any other errno causes raceproof_create_file() to fail with the |
| 1150 | * callback's return value and errno. |
| 1151 | * |
| 1152 | * Obviously, this function should be OK with being called again if it |
| 1153 | * fails with ENOENT or EISDIR. In other scenarios it will not be |
| 1154 | * called again. |
| 1155 | */ |
| 1156 | typedef int create_file_fn(const char *path, void *cb); |
| 1157 | |
| 1158 | /* |
| 1159 | * Create a file in dirname(path) by calling fn, creating leading |
| 1160 | * directories if necessary. Retry a few times in case we are racing |
| 1161 | * with another process that is trying to clean up the directory that |
| 1162 | * contains path. See the documentation for create_file_fn for more |
| 1163 | * details. |
| 1164 | * |
| 1165 | * Return the value and set the errno that resulted from the most |
| 1166 | * recent call of fn. fn is always called at least once, and will be |
| 1167 | * called more than once if it returns ENOENT or EISDIR. |
| 1168 | */ |
| 1169 | static int raceproof_create_file(struct files_ref_store *refs, |
| 1170 | const char *path, create_file_fn fn, void *cb) |
| 1171 | { |
| 1172 | /* |
| 1173 | * The number of times we will try to remove empty directories |
| 1174 | * in the way of path. This is only 1 because if another |
| 1175 | * process is racily creating directories that conflict with |
| 1176 | * us, we don't want to fight against them. |
| 1177 | */ |
| 1178 | int remove_directories_remaining = 1; |
| 1179 | |
| 1180 | /* |
| 1181 | * The number of times that we will try to create the |
| 1182 | * directories containing path. We are willing to attempt this |
| 1183 | * more than once, because another process could be trying to |
| 1184 | * clean up empty directories at the same time as we are |
| 1185 | * trying to create them. |
| 1186 | */ |
| 1187 | int create_directories_remaining = 3; |
| 1188 | |
| 1189 | /* A scratch copy of path, filled lazily if we need it: */ |
| 1190 | struct strbuf path_copy = STRBUF_INIT; |
| 1191 | |
| 1192 | int ret, save_errno; |
| 1193 | |
| 1194 | /* Sanity check: */ |
| 1195 | assert(*path); |
| 1196 | |
| 1197 | retry_fn: |
| 1198 | ret = fn(path, cb); |
| 1199 | save_errno = errno; |
| 1200 | if (!ret) |
| 1201 | goto out; |
| 1202 | |
| 1203 | if (errno == EISDIR && remove_directories_remaining-- > 0) { |
| 1204 | /* |
| 1205 | * A directory is in the way. Maybe it is empty; try |
| 1206 | * to remove it: |
| 1207 | */ |
| 1208 | if (!path_copy.len) |
| 1209 | strbuf_addstr(&path_copy, path); |
| 1210 | |
| 1211 | if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY)) |
| 1212 | goto retry_fn; |
| 1213 | } else if (errno == ENOENT && create_directories_remaining-- > 0) { |
| 1214 | /* |
| 1215 | * Maybe the containing directory didn't exist, or |
| 1216 | * maybe it was just deleted by a process that is |
| 1217 | * racing with us to clean up empty directories. Try |
| 1218 | * to create it: |
| 1219 | */ |
| 1220 | enum scld_error scld_result; |
| 1221 | |
| 1222 | if (!path_copy.len) |
| 1223 | strbuf_addstr(&path_copy, path); |
| 1224 | |
| 1225 | do { |
| 1226 | scld_result = safe_create_leading_directories(refs->base.repo, path_copy.buf); |
| 1227 | if (scld_result == SCLD_OK) |
| 1228 | goto retry_fn; |
| 1229 | } while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0); |
| 1230 | } |
| 1231 | |
| 1232 | out: |
| 1233 | strbuf_release(&path_copy); |
| 1234 | errno = save_errno; |
| 1235 | return ret; |
| 1236 | } |
| 1237 | |
| 1238 | static int remove_empty_directories(struct strbuf *path) |
| 1239 | { |
| 1240 | /* |
| 1241 | * we want to create a file but there is a directory there; |
| 1242 | * if that is an empty directory (or a directory that contains |
| 1243 | * only empty directories), remove them. |
| 1244 | */ |
| 1245 | return remove_dir_recursively(path, REMOVE_DIR_EMPTY_ONLY); |
| 1246 | } |
| 1247 | |
| 1248 | struct create_reflock_cb { |
| 1249 | struct lock_file *lk; |
| 1250 | struct repository *repo; |
| 1251 | }; |
| 1252 | |
| 1253 | static int create_reflock(const char *path, void *cb) |
| 1254 | { |
| 1255 | struct create_reflock_cb *data = cb; |
| 1256 | return repo_hold_lock_file_for_update_timeout( |
| 1257 | data->repo, data->lk, path, LOCK_NO_DEREF, |
| 1258 | get_files_ref_lock_timeout_ms(data->repo)) < 0 ? -1 : 0; |
| 1259 | } |
| 1260 | |
| 1261 | /* |
| 1262 | * Locks a ref returning the lock on success and NULL on failure. |
| 1263 | */ |
| 1264 | static struct ref_lock *lock_ref_oid_basic(struct files_ref_store *refs, |
| 1265 | const char *refname, |
| 1266 | struct strbuf *err) |
| 1267 | { |
| 1268 | struct strbuf ref_file = STRBUF_INIT; |
| 1269 | struct ref_lock *lock; |
| 1270 | struct create_reflock_cb cb_data; |
| 1271 | |
| 1272 | files_assert_main_repository(refs, "lock_ref_oid_basic"); |
| 1273 | assert(err); |
| 1274 | |
| 1275 | CALLOC_ARRAY(lock, 1); |
| 1276 | |
| 1277 | files_ref_path(refs, &ref_file, refname); |
| 1278 | |
| 1279 | /* |
| 1280 | * If the ref did not exist and we are creating it, make sure |
| 1281 | * there is no existing packed ref whose name begins with our |
| 1282 | * refname, nor a packed ref whose name is a proper prefix of |
| 1283 | * our refname. |
| 1284 | */ |
| 1285 | if (is_null_oid(&lock->old_oid) && |
| 1286 | refs_verify_refname_available(refs->packed_ref_store, refname, |
| 1287 | NULL, NULL, 0, err)) |
| 1288 | goto error_return; |
| 1289 | |
| 1290 | lock->ref_name = xstrdup(refname); |
| 1291 | lock->count = 1; |
| 1292 | cb_data.lk = &lock->lk; |
| 1293 | cb_data.repo = refs->base.repo; |
| 1294 | |
| 1295 | if (raceproof_create_file(refs, ref_file.buf, create_reflock, &cb_data)) { |
| 1296 | unable_to_lock_message(ref_file.buf, errno, err); |
| 1297 | goto error_return; |
| 1298 | } |
| 1299 | |
| 1300 | if (!refs_resolve_ref_unsafe(&refs->base, lock->ref_name, 0, |
| 1301 | &lock->old_oid, NULL)) |
| 1302 | oidclr(&lock->old_oid, refs->base.repo->hash_algo); |
| 1303 | goto out; |
| 1304 | |
| 1305 | error_return: |
| 1306 | unlock_ref(lock); |
| 1307 | lock = NULL; |
| 1308 | |
| 1309 | out: |
| 1310 | strbuf_release(&ref_file); |
| 1311 | return lock; |
| 1312 | } |
| 1313 | |
| 1314 | struct ref_to_prune { |
| 1315 | struct ref_to_prune *next; |
| 1316 | struct object_id oid; |
| 1317 | char name[FLEX_ARRAY]; |
| 1318 | }; |
| 1319 | |
| 1320 | enum { |
| 1321 | REMOVE_EMPTY_PARENTS_REF = 0x01, |
| 1322 | REMOVE_EMPTY_PARENTS_REFLOG = 0x02 |
| 1323 | }; |
| 1324 | |
| 1325 | /* |
| 1326 | * Remove empty parent directories associated with the specified |
| 1327 | * reference and/or its reflog, but spare [logs/]refs/ and immediate |
| 1328 | * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or |
| 1329 | * REMOVE_EMPTY_PARENTS_REFLOG. |
| 1330 | */ |
| 1331 | static void try_remove_empty_parents(struct files_ref_store *refs, |
| 1332 | const char *refname, |
| 1333 | unsigned int flags) |
| 1334 | { |
| 1335 | struct strbuf buf = STRBUF_INIT; |
| 1336 | struct strbuf sb = STRBUF_INIT; |
| 1337 | char *p, *q; |
| 1338 | int i; |
| 1339 | |
| 1340 | strbuf_addstr(&buf, refname); |
| 1341 | p = buf.buf; |
| 1342 | for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */ |
| 1343 | while (*p && *p != '/') |
| 1344 | p++; |
| 1345 | /* tolerate duplicate slashes; see check_refname_format() */ |
| 1346 | while (*p == '/') |
| 1347 | p++; |
| 1348 | } |
| 1349 | q = buf.buf + buf.len; |
| 1350 | while (flags & (REMOVE_EMPTY_PARENTS_REF | REMOVE_EMPTY_PARENTS_REFLOG)) { |
| 1351 | while (q > p && *q != '/') |
| 1352 | q--; |
| 1353 | while (q > p && *(q-1) == '/') |
| 1354 | q--; |
| 1355 | if (q == p) |
| 1356 | break; |
| 1357 | strbuf_setlen(&buf, q - buf.buf); |
| 1358 | |
| 1359 | strbuf_reset(&sb); |
| 1360 | files_ref_path(refs, &sb, buf.buf); |
| 1361 | if ((flags & REMOVE_EMPTY_PARENTS_REF) && rmdir(sb.buf)) |
| 1362 | flags &= ~REMOVE_EMPTY_PARENTS_REF; |
| 1363 | |
| 1364 | strbuf_reset(&sb); |
| 1365 | files_reflog_path(refs, &sb, buf.buf); |
| 1366 | if ((flags & REMOVE_EMPTY_PARENTS_REFLOG) && rmdir(sb.buf)) |
| 1367 | flags &= ~REMOVE_EMPTY_PARENTS_REFLOG; |
| 1368 | } |
| 1369 | strbuf_release(&buf); |
| 1370 | strbuf_release(&sb); |
| 1371 | } |
| 1372 | |
| 1373 | /* make sure nobody touched the ref, and unlink */ |
| 1374 | static void prune_ref(struct files_ref_store *refs, struct ref_to_prune *r) |
| 1375 | { |
| 1376 | struct ref_transaction *transaction; |
| 1377 | struct strbuf err = STRBUF_INIT; |
| 1378 | int ret = -1; |
| 1379 | |
| 1380 | if (check_refname_format(r->name, 0)) |
| 1381 | return; |
| 1382 | |
| 1383 | transaction = ref_store_transaction_begin(&refs->base, 0, &err); |
| 1384 | if (!transaction) |
| 1385 | goto cleanup; |
| 1386 | ref_transaction_add_update( |
| 1387 | transaction, r->name, |
| 1388 | REF_NO_DEREF | REF_HAVE_NEW | REF_HAVE_OLD | REF_IS_PRUNING, |
| 1389 | null_oid(refs->base.repo->hash_algo), &r->oid, NULL, NULL, NULL, |
| 1390 | NULL, NULL); |
| 1391 | if (ref_transaction_commit(transaction, &err)) |
| 1392 | goto cleanup; |
| 1393 | |
| 1394 | ret = 0; |
| 1395 | |
| 1396 | cleanup: |
| 1397 | if (ret) |
| 1398 | error("%s", err.buf); |
| 1399 | strbuf_release(&err); |
| 1400 | ref_transaction_free(transaction); |
| 1401 | return; |
| 1402 | } |
| 1403 | |
| 1404 | /* |
| 1405 | * Prune the loose versions of the references in the linked list |
| 1406 | * `*refs_to_prune`, freeing the entries in the list as we go. |
| 1407 | */ |
| 1408 | static void prune_refs(struct files_ref_store *refs, struct ref_to_prune **refs_to_prune) |
| 1409 | { |
| 1410 | while (*refs_to_prune) { |
| 1411 | struct ref_to_prune *r = *refs_to_prune; |
| 1412 | *refs_to_prune = r->next; |
| 1413 | prune_ref(refs, r); |
| 1414 | free(r); |
| 1415 | } |
| 1416 | } |
| 1417 | |
| 1418 | /* |
| 1419 | * Return true if the specified reference should be packed. |
| 1420 | */ |
| 1421 | static int should_pack_ref(struct files_ref_store *refs, |
| 1422 | const struct reference *ref, |
| 1423 | struct refs_optimize_opts *opts) |
| 1424 | { |
| 1425 | struct string_list_item *item; |
| 1426 | |
| 1427 | /* Do not pack per-worktree refs: */ |
| 1428 | if (parse_worktree_ref(ref->name, NULL, NULL, NULL) != |
| 1429 | REF_WORKTREE_SHARED) |
| 1430 | return 0; |
| 1431 | |
| 1432 | /* Do not pack symbolic refs: */ |
| 1433 | if (ref->flags & REF_ISSYMREF) |
| 1434 | return 0; |
| 1435 | |
| 1436 | /* Do not pack broken refs: */ |
| 1437 | if (!ref_resolves_to_object(ref->name, refs->base.repo, ref->oid, ref->flags)) |
| 1438 | return 0; |
| 1439 | |
| 1440 | if (ref_excluded(opts->exclusions, ref->name)) |
| 1441 | return 0; |
| 1442 | |
| 1443 | for_each_string_list_item(item, opts->includes) |
| 1444 | if (!wildmatch(item->string, ref->name, 0)) |
| 1445 | return 1; |
| 1446 | |
| 1447 | return 0; |
| 1448 | } |
| 1449 | |
| 1450 | static int should_pack_refs(struct files_ref_store *refs, |
| 1451 | struct refs_optimize_opts *opts) |
| 1452 | { |
| 1453 | struct ref_iterator *iter; |
| 1454 | size_t packed_size; |
| 1455 | size_t refcount = 0; |
| 1456 | size_t limit; |
| 1457 | int ret; |
| 1458 | |
| 1459 | if (!(opts->flags & REFS_OPTIMIZE_AUTO)) |
| 1460 | return 1; |
| 1461 | |
| 1462 | ret = packed_refs_size(refs->packed_ref_store, &packed_size); |
| 1463 | if (ret < 0) |
| 1464 | die("cannot determine packed-refs size"); |
| 1465 | |
| 1466 | /* |
| 1467 | * Packing loose references into the packed-refs file scales with the |
| 1468 | * number of references we're about to write. We thus decide whether we |
| 1469 | * repack refs by weighing the current size of the packed-refs file |
| 1470 | * against the number of loose references. This is done such that we do |
| 1471 | * not repack too often on repositories with a huge number of |
| 1472 | * references, where we can expect a lot of churn in the number of |
| 1473 | * references. |
| 1474 | * |
| 1475 | * As a heuristic, we repack if the number of loose references in the |
| 1476 | * repository exceeds `log2(nr_packed_refs) * 5`, where we estimate |
| 1477 | * `nr_packed_refs = packed_size / 100`, which scales as following: |
| 1478 | * |
| 1479 | * - 1kB ~ 10 packed refs: 16 refs |
| 1480 | * - 10kB ~ 100 packed refs: 33 refs |
| 1481 | * - 100kB ~ 1k packed refs: 49 refs |
| 1482 | * - 1MB ~ 10k packed refs: 66 refs |
| 1483 | * - 10MB ~ 100k packed refs: 82 refs |
| 1484 | * - 100MB ~ 1m packed refs: 99 refs |
| 1485 | * |
| 1486 | * We thus allow roughly 16 additional loose refs per factor of ten of |
| 1487 | * packed refs. This heuristic may be tweaked in the future, but should |
| 1488 | * serve as a sufficiently good first iteration. |
| 1489 | */ |
| 1490 | limit = log2u(packed_size / 100) * 5; |
| 1491 | if (limit < 16) |
| 1492 | limit = 16; |
| 1493 | |
| 1494 | iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, 0), NULL, |
| 1495 | refs->base.repo, 0); |
| 1496 | while ((ret = ref_iterator_advance(iter)) == ITER_OK) { |
| 1497 | if (should_pack_ref(refs, &iter->ref, opts)) |
| 1498 | refcount++; |
| 1499 | if (refcount >= limit) { |
| 1500 | ref_iterator_free(iter); |
| 1501 | return 1; |
| 1502 | } |
| 1503 | } |
| 1504 | |
| 1505 | if (ret != ITER_DONE) |
| 1506 | die("error while iterating over references"); |
| 1507 | |
| 1508 | ref_iterator_free(iter); |
| 1509 | return 0; |
| 1510 | } |
| 1511 | |
| 1512 | static int files_optimize(struct ref_store *ref_store, |
| 1513 | struct refs_optimize_opts *opts) |
| 1514 | { |
| 1515 | struct files_ref_store *refs = |
| 1516 | files_downcast(ref_store, REF_STORE_WRITE | REF_STORE_ODB, |
| 1517 | "pack_refs"); |
| 1518 | struct ref_iterator *iter; |
| 1519 | int ok; |
| 1520 | struct ref_to_prune *refs_to_prune = NULL; |
| 1521 | struct strbuf err = STRBUF_INIT; |
| 1522 | struct ref_transaction *transaction; |
| 1523 | |
| 1524 | if (!should_pack_refs(refs, opts)) |
| 1525 | return 0; |
| 1526 | |
| 1527 | transaction = ref_store_transaction_begin(refs->packed_ref_store, |
| 1528 | 0, &err); |
| 1529 | if (!transaction) |
| 1530 | return -1; |
| 1531 | |
| 1532 | packed_refs_lock(refs->packed_ref_store, LOCK_DIE_ON_ERROR, &err); |
| 1533 | |
| 1534 | iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, 0), NULL, |
| 1535 | refs->base.repo, 0); |
| 1536 | while ((ok = ref_iterator_advance(iter)) == ITER_OK) { |
| 1537 | /* |
| 1538 | * If the loose reference can be packed, add an entry |
| 1539 | * in the packed ref cache. If the reference should be |
| 1540 | * pruned, also add it to refs_to_prune. |
| 1541 | */ |
| 1542 | if (!should_pack_ref(refs, &iter->ref, opts)) |
| 1543 | continue; |
| 1544 | |
| 1545 | /* |
| 1546 | * Add a reference creation for this reference to the |
| 1547 | * packed-refs transaction: |
| 1548 | */ |
| 1549 | if (ref_transaction_update(transaction, iter->ref.name, |
| 1550 | iter->ref.oid, NULL, NULL, NULL, |
| 1551 | REF_NO_DEREF, NULL, &err)) |
| 1552 | die("failure preparing to create packed reference %s: %s", |
| 1553 | iter->ref.name, err.buf); |
| 1554 | |
| 1555 | /* Schedule the loose reference for pruning if requested. */ |
| 1556 | if ((opts->flags & REFS_OPTIMIZE_PRUNE)) { |
| 1557 | struct ref_to_prune *n; |
| 1558 | FLEX_ALLOC_STR(n, name, iter->ref.name); |
| 1559 | oidcpy(&n->oid, iter->ref.oid); |
| 1560 | n->next = refs_to_prune; |
| 1561 | refs_to_prune = n; |
| 1562 | } |
| 1563 | } |
| 1564 | if (ok != ITER_DONE) |
| 1565 | die("error while iterating over references"); |
| 1566 | |
| 1567 | if (ref_transaction_commit(transaction, &err)) |
| 1568 | die("unable to write new packed-refs: %s", err.buf); |
| 1569 | |
| 1570 | ref_transaction_free(transaction); |
| 1571 | |
| 1572 | packed_refs_unlock(refs->packed_ref_store); |
| 1573 | |
| 1574 | prune_refs(refs, &refs_to_prune); |
| 1575 | ref_iterator_free(iter); |
| 1576 | strbuf_release(&err); |
| 1577 | return 0; |
| 1578 | } |
| 1579 | |
| 1580 | static int files_optimize_required(struct ref_store *ref_store, |
| 1581 | struct refs_optimize_opts *opts, |
| 1582 | bool *required) |
| 1583 | { |
| 1584 | struct files_ref_store *refs = files_downcast(ref_store, REF_STORE_READ, |
| 1585 | "optimize_required"); |
| 1586 | *required = should_pack_refs(refs, opts); |
| 1587 | return 0; |
| 1588 | } |
| 1589 | |
| 1590 | /* |
| 1591 | * People using contrib's git-new-workdir have .git/logs/refs -> |
| 1592 | * /some/other/path/.git/logs/refs, and that may live on another device. |
| 1593 | * |
| 1594 | * IOW, to avoid cross device rename errors, the temporary renamed log must |
| 1595 | * live into logs/refs. |
| 1596 | */ |
| 1597 | #define TMP_RENAMED_LOG "refs/.tmp-renamed-log" |
| 1598 | |
| 1599 | struct rename_cb { |
| 1600 | const char *tmp_renamed_log; |
| 1601 | int true_errno; |
| 1602 | }; |
| 1603 | |
| 1604 | static int rename_tmp_log_callback(const char *path, void *cb_data) |
| 1605 | { |
| 1606 | struct rename_cb *cb = cb_data; |
| 1607 | |
| 1608 | if (rename(cb->tmp_renamed_log, path)) { |
| 1609 | /* |
| 1610 | * rename(a, b) when b is an existing directory ought |
| 1611 | * to result in ISDIR, but Solaris 5.8 gives ENOTDIR. |
| 1612 | * Sheesh. Record the true errno for error reporting, |
| 1613 | * but report EISDIR to raceproof_create_file() so |
| 1614 | * that it knows to retry. |
| 1615 | */ |
| 1616 | cb->true_errno = errno; |
| 1617 | if (errno == ENOTDIR) |
| 1618 | errno = EISDIR; |
| 1619 | return -1; |
| 1620 | } else { |
| 1621 | return 0; |
| 1622 | } |
| 1623 | } |
| 1624 | |
| 1625 | static int rename_tmp_log(struct files_ref_store *refs, const char *newrefname) |
| 1626 | { |
| 1627 | struct strbuf path = STRBUF_INIT; |
| 1628 | struct strbuf tmp = STRBUF_INIT; |
| 1629 | struct rename_cb cb; |
| 1630 | int ret; |
| 1631 | |
| 1632 | files_reflog_path(refs, &path, newrefname); |
| 1633 | files_reflog_path(refs, &tmp, TMP_RENAMED_LOG); |
| 1634 | cb.tmp_renamed_log = tmp.buf; |
| 1635 | ret = raceproof_create_file(refs, path.buf, rename_tmp_log_callback, &cb); |
| 1636 | if (ret) { |
| 1637 | if (errno == EISDIR) |
| 1638 | error("directory not empty: %s", path.buf); |
| 1639 | else |
| 1640 | error("unable to move logfile %s to %s: %s", |
| 1641 | tmp.buf, path.buf, |
| 1642 | strerror(cb.true_errno)); |
| 1643 | } |
| 1644 | |
| 1645 | strbuf_release(&path); |
| 1646 | strbuf_release(&tmp); |
| 1647 | return ret; |
| 1648 | } |
| 1649 | |
| 1650 | static enum ref_transaction_error write_ref_to_lockfile(struct files_ref_store *refs, |
| 1651 | struct ref_lock *lock, |
| 1652 | const struct object_id *oid, |
| 1653 | struct strbuf *err); |
| 1654 | static int commit_ref_update(struct files_ref_store *refs, |
| 1655 | struct ref_lock *lock, |
| 1656 | const struct object_id *oid, const char *logmsg, |
| 1657 | int flags, |
| 1658 | struct strbuf *err); |
| 1659 | |
| 1660 | /* |
| 1661 | * Emit a better error message than lockfile.c's |
| 1662 | * unable_to_lock_message() would in case there is a D/F conflict with |
| 1663 | * another existing reference. If there would be a conflict, emit an error |
| 1664 | * message and return false; otherwise, return true. |
| 1665 | * |
| 1666 | * Note that this function is not safe against all races with other |
| 1667 | * processes, and that's not its job. We'll emit a more verbose error on D/f |
| 1668 | * conflicts if we get past it into lock_ref_oid_basic(). |
| 1669 | */ |
| 1670 | static int refs_rename_ref_available(struct ref_store *refs, |
| 1671 | const char *old_refname, |
| 1672 | const char *new_refname) |
| 1673 | { |
| 1674 | struct string_list skip = STRING_LIST_INIT_NODUP; |
| 1675 | struct strbuf err = STRBUF_INIT; |
| 1676 | int ok; |
| 1677 | |
| 1678 | string_list_insert(&skip, old_refname); |
| 1679 | ok = !refs_verify_refname_available(refs, new_refname, |
| 1680 | NULL, &skip, 0, &err); |
| 1681 | if (!ok) |
| 1682 | error("%s", err.buf); |
| 1683 | |
| 1684 | string_list_clear(&skip, 0); |
| 1685 | strbuf_release(&err); |
| 1686 | return ok; |
| 1687 | } |
| 1688 | |
| 1689 | static int files_copy_or_rename_ref(struct ref_store *ref_store, |
| 1690 | const char *oldrefname, const char *newrefname, |
| 1691 | const char *logmsg, int copy) |
| 1692 | { |
| 1693 | struct files_ref_store *refs = |
| 1694 | files_downcast(ref_store, REF_STORE_WRITE, "rename_ref"); |
| 1695 | struct object_id orig_oid; |
| 1696 | int flag = 0, logmoved = 0; |
| 1697 | struct ref_lock *lock; |
| 1698 | struct stat loginfo; |
| 1699 | struct strbuf sb_oldref = STRBUF_INIT; |
| 1700 | struct strbuf sb_newref = STRBUF_INIT; |
| 1701 | struct strbuf tmp_renamed_log = STRBUF_INIT; |
| 1702 | int log, ret; |
| 1703 | struct strbuf err = STRBUF_INIT; |
| 1704 | |
| 1705 | files_reflog_path(refs, &sb_oldref, oldrefname); |
| 1706 | files_reflog_path(refs, &sb_newref, newrefname); |
| 1707 | files_reflog_path(refs, &tmp_renamed_log, TMP_RENAMED_LOG); |
| 1708 | |
| 1709 | log = !lstat(sb_oldref.buf, &loginfo); |
| 1710 | if (log && S_ISLNK(loginfo.st_mode)) { |
| 1711 | ret = error("reflog for %s is a symlink", oldrefname); |
| 1712 | goto out; |
| 1713 | } |
| 1714 | |
| 1715 | if (!refs_resolve_ref_unsafe(&refs->base, oldrefname, |
| 1716 | RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, |
| 1717 | &orig_oid, &flag)) { |
| 1718 | ret = error("refname %s not found", oldrefname); |
| 1719 | goto out; |
| 1720 | } |
| 1721 | |
| 1722 | if (flag & REF_ISSYMREF) { |
| 1723 | if (copy) |
| 1724 | ret = error("refname %s is a symbolic ref, copying it is not supported", |
| 1725 | oldrefname); |
| 1726 | else |
| 1727 | ret = error("refname %s is a symbolic ref, renaming it is not supported", |
| 1728 | oldrefname); |
| 1729 | goto out; |
| 1730 | } |
| 1731 | if (!refs_rename_ref_available(&refs->base, oldrefname, newrefname)) { |
| 1732 | ret = 1; |
| 1733 | goto out; |
| 1734 | } |
| 1735 | |
| 1736 | if (!copy && log && rename(sb_oldref.buf, tmp_renamed_log.buf)) { |
| 1737 | ret = error("unable to move logfile logs/%s to logs/"TMP_RENAMED_LOG": %s", |
| 1738 | oldrefname, strerror(errno)); |
| 1739 | goto out; |
| 1740 | } |
| 1741 | |
| 1742 | if (copy && log && copy_file(refs->base.repo, tmp_renamed_log.buf, sb_oldref.buf, 0644)) { |
| 1743 | ret = error("unable to copy logfile logs/%s to logs/"TMP_RENAMED_LOG": %s", |
| 1744 | oldrefname, strerror(errno)); |
| 1745 | goto out; |
| 1746 | } |
| 1747 | |
| 1748 | if (!copy && refs_delete_ref(&refs->base, logmsg, oldrefname, |
| 1749 | &orig_oid, REF_NO_DEREF)) { |
| 1750 | error("unable to delete old %s", oldrefname); |
| 1751 | goto rollback; |
| 1752 | } |
| 1753 | |
| 1754 | /* |
| 1755 | * Since we are doing a shallow lookup, oid is not the |
| 1756 | * correct value to pass to delete_ref as old_oid. But that |
| 1757 | * doesn't matter, because an old_oid check wouldn't add to |
| 1758 | * the safety anyway; we want to delete the reference whatever |
| 1759 | * its current value. |
| 1760 | */ |
| 1761 | if (!copy && refs_resolve_ref_unsafe(&refs->base, newrefname, |
| 1762 | RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, |
| 1763 | NULL, NULL) && |
| 1764 | refs_delete_ref(&refs->base, NULL, newrefname, |
| 1765 | NULL, REF_NO_DEREF)) { |
| 1766 | if (errno == EISDIR) { |
| 1767 | struct strbuf path = STRBUF_INIT; |
| 1768 | int result; |
| 1769 | |
| 1770 | files_ref_path(refs, &path, newrefname); |
| 1771 | result = remove_empty_directories(&path); |
| 1772 | strbuf_release(&path); |
| 1773 | |
| 1774 | if (result) { |
| 1775 | error("Directory not empty: %s", newrefname); |
| 1776 | goto rollback; |
| 1777 | } |
| 1778 | } else { |
| 1779 | error("unable to delete existing %s", newrefname); |
| 1780 | goto rollback; |
| 1781 | } |
| 1782 | } |
| 1783 | |
| 1784 | if (log && rename_tmp_log(refs, newrefname)) |
| 1785 | goto rollback; |
| 1786 | |
| 1787 | logmoved = log; |
| 1788 | |
| 1789 | lock = lock_ref_oid_basic(refs, newrefname, &err); |
| 1790 | if (!lock) { |
| 1791 | if (copy) |
| 1792 | error("unable to copy '%s' to '%s': %s", oldrefname, newrefname, err.buf); |
| 1793 | else |
| 1794 | error("unable to rename '%s' to '%s': %s", oldrefname, newrefname, err.buf); |
| 1795 | strbuf_release(&err); |
| 1796 | goto rollback; |
| 1797 | } |
| 1798 | oidcpy(&lock->old_oid, &orig_oid); |
| 1799 | |
| 1800 | if (write_ref_to_lockfile(refs, lock, &orig_oid, &err) || |
| 1801 | commit_ref_update(refs, lock, &orig_oid, logmsg, 0, &err)) { |
| 1802 | error("unable to write current sha1 into %s: %s", newrefname, err.buf); |
| 1803 | strbuf_release(&err); |
| 1804 | goto rollback; |
| 1805 | } |
| 1806 | |
| 1807 | ret = 0; |
| 1808 | goto out; |
| 1809 | |
| 1810 | rollback: |
| 1811 | lock = lock_ref_oid_basic(refs, oldrefname, &err); |
| 1812 | if (!lock) { |
| 1813 | error("unable to lock %s for rollback: %s", oldrefname, err.buf); |
| 1814 | strbuf_release(&err); |
| 1815 | goto rollbacklog; |
| 1816 | } |
| 1817 | |
| 1818 | if (write_ref_to_lockfile(refs, lock, &orig_oid, &err) || |
| 1819 | commit_ref_update(refs, lock, &orig_oid, NULL, REF_SKIP_CREATE_REFLOG, &err)) { |
| 1820 | error("unable to write current sha1 into %s: %s", oldrefname, err.buf); |
| 1821 | strbuf_release(&err); |
| 1822 | } |
| 1823 | |
| 1824 | rollbacklog: |
| 1825 | if (logmoved && rename(sb_newref.buf, sb_oldref.buf)) |
| 1826 | error("unable to restore logfile %s from %s: %s", |
| 1827 | oldrefname, newrefname, strerror(errno)); |
| 1828 | if (!logmoved && log && |
| 1829 | rename(tmp_renamed_log.buf, sb_oldref.buf)) |
| 1830 | error("unable to restore logfile %s from logs/"TMP_RENAMED_LOG": %s", |
| 1831 | oldrefname, strerror(errno)); |
| 1832 | ret = 1; |
| 1833 | out: |
| 1834 | strbuf_release(&sb_newref); |
| 1835 | strbuf_release(&sb_oldref); |
| 1836 | strbuf_release(&tmp_renamed_log); |
| 1837 | |
| 1838 | return ret; |
| 1839 | } |
| 1840 | |
| 1841 | static int files_rename_ref(struct ref_store *ref_store, |
| 1842 | const char *oldrefname, const char *newrefname, |
| 1843 | const char *logmsg) |
| 1844 | { |
| 1845 | return files_copy_or_rename_ref(ref_store, oldrefname, |
| 1846 | newrefname, logmsg, 0); |
| 1847 | } |
| 1848 | |
| 1849 | static int files_copy_ref(struct ref_store *ref_store, |
| 1850 | const char *oldrefname, const char *newrefname, |
| 1851 | const char *logmsg) |
| 1852 | { |
| 1853 | return files_copy_or_rename_ref(ref_store, oldrefname, |
| 1854 | newrefname, logmsg, 1); |
| 1855 | } |
| 1856 | |
| 1857 | static int close_ref_gently(struct ref_lock *lock) |
| 1858 | { |
| 1859 | if (close_lock_file_gently(&lock->lk)) |
| 1860 | return -1; |
| 1861 | return 0; |
| 1862 | } |
| 1863 | |
| 1864 | static int commit_ref(struct ref_lock *lock) |
| 1865 | { |
| 1866 | char *path = get_locked_file_path(&lock->lk); |
| 1867 | struct stat st; |
| 1868 | |
| 1869 | if (!lstat(path, &st) && S_ISDIR(st.st_mode)) { |
| 1870 | /* |
| 1871 | * There is a directory at the path we want to rename |
| 1872 | * the lockfile to. Hopefully it is empty; try to |
| 1873 | * delete it. |
| 1874 | */ |
| 1875 | size_t len = strlen(path); |
| 1876 | struct strbuf sb_path = STRBUF_INIT; |
| 1877 | |
| 1878 | strbuf_attach(&sb_path, path, len, len + 1); |
| 1879 | |
| 1880 | /* |
| 1881 | * If this fails, commit_lock_file() will also fail |
| 1882 | * and will report the problem. |
| 1883 | */ |
| 1884 | remove_empty_directories(&sb_path); |
| 1885 | strbuf_release(&sb_path); |
| 1886 | } else { |
| 1887 | free(path); |
| 1888 | } |
| 1889 | |
| 1890 | if (commit_lock_file(&lock->lk)) |
| 1891 | return -1; |
| 1892 | return 0; |
| 1893 | } |
| 1894 | |
| 1895 | static int open_or_create_logfile(const char *path, void *cb) |
| 1896 | { |
| 1897 | int *fd = cb; |
| 1898 | |
| 1899 | *fd = open(path, O_APPEND | O_WRONLY | O_CREAT, 0666); |
| 1900 | return (*fd < 0) ? -1 : 0; |
| 1901 | } |
| 1902 | |
| 1903 | /* |
| 1904 | * Create a reflog for a ref. If force_create = 0, only create the |
| 1905 | * reflog for certain refs (those for which should_autocreate_reflog |
| 1906 | * returns non-zero). Otherwise, create it regardless of the reference |
| 1907 | * name. If the logfile already existed or was created, return 0 and |
| 1908 | * set *logfd to the file descriptor opened for appending to the file. |
| 1909 | * If no logfile exists and we decided not to create one, return 0 and |
| 1910 | * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and |
| 1911 | * return -1. |
| 1912 | */ |
| 1913 | static int log_ref_setup(struct files_ref_store *refs, |
| 1914 | const char *refname, int force_create, |
| 1915 | int *logfd, struct strbuf *err) |
| 1916 | { |
| 1917 | enum log_refs_config log_refs_cfg = files_ref_store_write_options(refs)->log_all_ref_updates; |
| 1918 | struct strbuf logfile_sb = STRBUF_INIT; |
| 1919 | char *logfile; |
| 1920 | |
| 1921 | if (log_refs_cfg == LOG_REFS_UNSET) |
| 1922 | log_refs_cfg = is_bare_repository(refs->base.repo) ? LOG_REFS_NONE : LOG_REFS_NORMAL; |
| 1923 | |
| 1924 | files_reflog_path(refs, &logfile_sb, refname); |
| 1925 | logfile = strbuf_detach(&logfile_sb, NULL); |
| 1926 | |
| 1927 | if (force_create || should_autocreate_reflog(log_refs_cfg, refname)) { |
| 1928 | if (raceproof_create_file(refs, logfile, open_or_create_logfile, logfd)) { |
| 1929 | if (errno == ENOENT) |
| 1930 | strbuf_addf(err, "unable to create directory for '%s': " |
| 1931 | "%s", logfile, strerror(errno)); |
| 1932 | else if (errno == EISDIR) |
| 1933 | strbuf_addf(err, "there are still logs under '%s'", |
| 1934 | logfile); |
| 1935 | else |
| 1936 | strbuf_addf(err, "unable to append to '%s': %s", |
| 1937 | logfile, strerror(errno)); |
| 1938 | |
| 1939 | goto error; |
| 1940 | } |
| 1941 | } else { |
| 1942 | *logfd = open(logfile, O_APPEND | O_WRONLY); |
| 1943 | if (*logfd < 0) { |
| 1944 | if (errno == ENOENT || errno == EISDIR) { |
| 1945 | /* |
| 1946 | * The logfile doesn't already exist, |
| 1947 | * but that is not an error; it only |
| 1948 | * means that we won't write log |
| 1949 | * entries to it. |
| 1950 | */ |
| 1951 | ; |
| 1952 | } else { |
| 1953 | strbuf_addf(err, "unable to append to '%s': %s", |
| 1954 | logfile, strerror(errno)); |
| 1955 | goto error; |
| 1956 | } |
| 1957 | } |
| 1958 | } |
| 1959 | |
| 1960 | if (*logfd >= 0) |
| 1961 | adjust_shared_perm(refs->base.repo, logfile); |
| 1962 | |
| 1963 | free(logfile); |
| 1964 | return 0; |
| 1965 | |
| 1966 | error: |
| 1967 | free(logfile); |
| 1968 | return -1; |
| 1969 | } |
| 1970 | |
| 1971 | static int files_create_reflog(struct ref_store *ref_store, const char *refname, |
| 1972 | struct strbuf *err) |
| 1973 | { |
| 1974 | struct files_ref_store *refs = |
| 1975 | files_downcast(ref_store, REF_STORE_WRITE, "create_reflog"); |
| 1976 | int fd; |
| 1977 | |
| 1978 | if (log_ref_setup(refs, refname, 1, &fd, err)) |
| 1979 | return -1; |
| 1980 | |
| 1981 | if (fd >= 0) |
| 1982 | close(fd); |
| 1983 | |
| 1984 | return 0; |
| 1985 | } |
| 1986 | |
| 1987 | static int log_ref_write_fd(int fd, const struct object_id *old_oid, |
| 1988 | const struct object_id *new_oid, |
| 1989 | const char *committer, const char *msg) |
| 1990 | { |
| 1991 | struct strbuf sb = STRBUF_INIT; |
| 1992 | int ret = 0; |
| 1993 | |
| 1994 | if (!committer) |
| 1995 | committer = git_committer_info(0); |
| 1996 | |
| 1997 | strbuf_addf(&sb, "%s %s %s", oid_to_hex(old_oid), oid_to_hex(new_oid), committer); |
| 1998 | if (msg && *msg) { |
| 1999 | strbuf_addch(&sb, '\t'); |
| 2000 | strbuf_addstr(&sb, msg); |
| 2001 | } |
| 2002 | strbuf_addch(&sb, '\n'); |
| 2003 | if (write_in_full(fd, sb.buf, sb.len) < 0) |
| 2004 | ret = -1; |
| 2005 | strbuf_release(&sb); |
| 2006 | return ret; |
| 2007 | } |
| 2008 | |
| 2009 | static int files_log_ref_write(struct files_ref_store *refs, |
| 2010 | const char *refname, |
| 2011 | const struct object_id *old_oid, |
| 2012 | const struct object_id *new_oid, |
| 2013 | const char *committer_info, const char *msg, |
| 2014 | int flags, struct strbuf *err) |
| 2015 | { |
| 2016 | int logfd, result; |
| 2017 | |
| 2018 | if (flags & REF_SKIP_CREATE_REFLOG) |
| 2019 | return 0; |
| 2020 | |
| 2021 | result = log_ref_setup(refs, refname, |
| 2022 | flags & REF_FORCE_CREATE_REFLOG, |
| 2023 | &logfd, err); |
| 2024 | |
| 2025 | if (result) |
| 2026 | return result; |
| 2027 | |
| 2028 | if (logfd < 0) |
| 2029 | return 0; |
| 2030 | result = log_ref_write_fd(logfd, old_oid, new_oid, committer_info, msg); |
| 2031 | if (result) { |
| 2032 | struct strbuf sb = STRBUF_INIT; |
| 2033 | int save_errno = errno; |
| 2034 | |
| 2035 | files_reflog_path(refs, &sb, refname); |
| 2036 | strbuf_addf(err, "unable to append to '%s': %s", |
| 2037 | sb.buf, strerror(save_errno)); |
| 2038 | strbuf_release(&sb); |
| 2039 | close(logfd); |
| 2040 | return -1; |
| 2041 | } |
| 2042 | if (close(logfd)) { |
| 2043 | struct strbuf sb = STRBUF_INIT; |
| 2044 | int save_errno = errno; |
| 2045 | |
| 2046 | files_reflog_path(refs, &sb, refname); |
| 2047 | strbuf_addf(err, "unable to append to '%s': %s", |
| 2048 | sb.buf, strerror(save_errno)); |
| 2049 | strbuf_release(&sb); |
| 2050 | return -1; |
| 2051 | } |
| 2052 | return 0; |
| 2053 | } |
| 2054 | |
| 2055 | /* |
| 2056 | * Write oid into the open lockfile, then close the lockfile. On |
| 2057 | * errors, rollback the lockfile, fill in *err and return -1. |
| 2058 | */ |
| 2059 | static enum ref_transaction_error write_ref_to_lockfile(struct files_ref_store *refs, |
| 2060 | struct ref_lock *lock, |
| 2061 | const struct object_id *oid, |
| 2062 | struct strbuf *err) |
| 2063 | { |
| 2064 | static char term = '\n'; |
| 2065 | int fd; |
| 2066 | |
| 2067 | fd = get_lock_file_fd(&lock->lk); |
| 2068 | if (write_in_full(fd, oid_to_hex(oid), refs->base.repo->hash_algo->hexsz) < 0 || |
| 2069 | write_in_full(fd, &term, 1) < 0 || |
| 2070 | fsync_component(FSYNC_COMPONENT_REFERENCE, get_lock_file_fd(&lock->lk)) < 0 || |
| 2071 | close_ref_gently(lock) < 0) { |
| 2072 | strbuf_addf(err, |
| 2073 | "couldn't write '%s'", get_lock_file_path(&lock->lk)); |
| 2074 | unlock_ref(lock); |
| 2075 | return REF_TRANSACTION_ERROR_GENERIC; |
| 2076 | } |
| 2077 | return 0; |
| 2078 | } |
| 2079 | |
| 2080 | /* |
| 2081 | * Commit a change to a loose reference that has already been written |
| 2082 | * to the loose reference lockfile. Also update the reflogs if |
| 2083 | * necessary, using the specified lockmsg (which can be NULL). |
| 2084 | */ |
| 2085 | static int commit_ref_update(struct files_ref_store *refs, |
| 2086 | struct ref_lock *lock, |
| 2087 | const struct object_id *oid, const char *logmsg, |
| 2088 | int flags, |
| 2089 | struct strbuf *err) |
| 2090 | { |
| 2091 | files_assert_main_repository(refs, "commit_ref_update"); |
| 2092 | |
| 2093 | clear_loose_ref_cache(refs); |
| 2094 | if (files_log_ref_write(refs, lock->ref_name, &lock->old_oid, oid, NULL, |
| 2095 | logmsg, flags, err)) { |
| 2096 | char *old_msg = strbuf_detach(err, NULL); |
| 2097 | strbuf_addf(err, "cannot update the ref '%s': %s", |
| 2098 | lock->ref_name, old_msg); |
| 2099 | free(old_msg); |
| 2100 | unlock_ref(lock); |
| 2101 | return -1; |
| 2102 | } |
| 2103 | |
| 2104 | if (strcmp(lock->ref_name, "HEAD") != 0) { |
| 2105 | /* |
| 2106 | * Special hack: If a branch is updated directly and HEAD |
| 2107 | * points to it (may happen on the remote side of a push |
| 2108 | * for example) then logically the HEAD reflog should be |
| 2109 | * updated too. |
| 2110 | * A generic solution implies reverse symref information, |
| 2111 | * but finding all symrefs pointing to the given branch |
| 2112 | * would be rather costly for this rare event (the direct |
| 2113 | * update of a branch) to be worth it. So let's cheat and |
| 2114 | * check with HEAD only which should cover 99% of all usage |
| 2115 | * scenarios (even 100% of the default ones). |
| 2116 | */ |
| 2117 | int head_flag; |
| 2118 | const char *head_ref; |
| 2119 | |
| 2120 | head_ref = refs_resolve_ref_unsafe(&refs->base, "HEAD", |
| 2121 | RESOLVE_REF_READING, |
| 2122 | NULL, &head_flag); |
| 2123 | if (head_ref && (head_flag & REF_ISSYMREF) && |
| 2124 | !strcmp(head_ref, lock->ref_name)) { |
| 2125 | struct strbuf log_err = STRBUF_INIT; |
| 2126 | if (files_log_ref_write(refs, "HEAD", &lock->old_oid, |
| 2127 | oid, NULL, logmsg, flags, |
| 2128 | &log_err)) { |
| 2129 | error("%s", log_err.buf); |
| 2130 | strbuf_release(&log_err); |
| 2131 | } |
| 2132 | } |
| 2133 | } |
| 2134 | |
| 2135 | if (commit_ref(lock)) { |
| 2136 | strbuf_addf(err, "couldn't set '%s'", lock->ref_name); |
| 2137 | unlock_ref(lock); |
| 2138 | return -1; |
| 2139 | } |
| 2140 | |
| 2141 | unlock_ref(lock); |
| 2142 | return 0; |
| 2143 | } |
| 2144 | |
| 2145 | #if defined(NO_SYMLINK_HEAD) || defined(WITH_BREAKING_CHANGES) |
| 2146 | #define create_ref_symlink(a, b) (-1) |
| 2147 | #else |
| 2148 | static int create_ref_symlink(struct ref_lock *lock, const char *target) |
| 2149 | { |
| 2150 | static int warn_once = 1; |
| 2151 | char *ref_path; |
| 2152 | int ret = -1; |
| 2153 | |
| 2154 | ref_path = get_locked_file_path(&lock->lk); |
| 2155 | unlink(ref_path); |
| 2156 | ret = symlink(target, ref_path); |
| 2157 | free(ref_path); |
| 2158 | |
| 2159 | if (ret) |
| 2160 | fprintf(stderr, "no symlink - falling back to symbolic ref\n"); |
| 2161 | |
| 2162 | if (warn_once) |
| 2163 | warning(_("'core.preferSymlinkRefs=true' is nominated for removal.\n" |
| 2164 | "hint: The use of symbolic links for symbolic refs is deprecated\n" |
| 2165 | "hint: and will be removed in Git 3.0. The configuration that\n" |
| 2166 | "hint: tells Git to use them is thus going away. You can unset\n" |
| 2167 | "hint: it with:\n" |
| 2168 | "hint:\n" |
| 2169 | "hint:\tgit config unset core.preferSymlinkRefs\n" |
| 2170 | "hint:\n" |
| 2171 | "hint: Git will then use the textual symref format instead.")); |
| 2172 | warn_once = 0; |
| 2173 | |
| 2174 | return ret; |
| 2175 | } |
| 2176 | #endif |
| 2177 | |
| 2178 | static int create_symref_lock(struct ref_lock *lock, const char *target, |
| 2179 | struct strbuf *err) |
| 2180 | { |
| 2181 | if (!fdopen_lock_file(&lock->lk, "w")) { |
| 2182 | strbuf_addf(err, "unable to fdopen %s: %s", |
| 2183 | get_lock_file_path(&lock->lk), strerror(errno)); |
| 2184 | return -1; |
| 2185 | } |
| 2186 | |
| 2187 | if (fprintf(get_lock_file_fp(&lock->lk), "ref: %s\n", target) < 0) { |
| 2188 | strbuf_addf(err, "unable to write to %s: %s", |
| 2189 | get_lock_file_path(&lock->lk), strerror(errno)); |
| 2190 | return -1; |
| 2191 | } |
| 2192 | |
| 2193 | return 0; |
| 2194 | } |
| 2195 | |
| 2196 | static int files_reflog_exists(struct ref_store *ref_store, |
| 2197 | const char *refname) |
| 2198 | { |
| 2199 | struct files_ref_store *refs = |
| 2200 | files_downcast(ref_store, REF_STORE_READ, "reflog_exists"); |
| 2201 | struct strbuf sb = STRBUF_INIT; |
| 2202 | struct stat st; |
| 2203 | int ret; |
| 2204 | |
| 2205 | files_reflog_path(refs, &sb, refname); |
| 2206 | ret = !lstat(sb.buf, &st) && S_ISREG(st.st_mode); |
| 2207 | strbuf_release(&sb); |
| 2208 | return ret; |
| 2209 | } |
| 2210 | |
| 2211 | static int files_delete_reflog(struct ref_store *ref_store, |
| 2212 | const char *refname) |
| 2213 | { |
| 2214 | struct files_ref_store *refs = |
| 2215 | files_downcast(ref_store, REF_STORE_WRITE, "delete_reflog"); |
| 2216 | struct strbuf sb = STRBUF_INIT; |
| 2217 | int ret; |
| 2218 | |
| 2219 | files_reflog_path(refs, &sb, refname); |
| 2220 | ret = remove_path(sb.buf); |
| 2221 | strbuf_release(&sb); |
| 2222 | return ret; |
| 2223 | } |
| 2224 | |
| 2225 | static int show_one_reflog_ent(struct files_ref_store *refs, |
| 2226 | const char *refname, |
| 2227 | struct strbuf *sb, |
| 2228 | each_reflog_ent_fn fn, void *cb_data) |
| 2229 | { |
| 2230 | struct object_id ooid, noid; |
| 2231 | char *email_end, *message; |
| 2232 | timestamp_t timestamp; |
| 2233 | int tz; |
| 2234 | char *p = sb->buf; |
| 2235 | |
| 2236 | /* old SP new SP name <email> SP time TAB msg LF */ |
| 2237 | if (!sb->len || sb->buf[sb->len - 1] != '\n' || |
| 2238 | parse_oid_hex_algop(p, &ooid, &p, refs->base.repo->hash_algo) || *p++ != ' ' || |
| 2239 | parse_oid_hex_algop(p, &noid, &p, refs->base.repo->hash_algo) || *p++ != ' ' || |
| 2240 | !(email_end = strchr(p, '>')) || |
| 2241 | email_end[1] != ' ' || |
| 2242 | !(timestamp = parse_timestamp(email_end + 2, &message, 10)) || |
| 2243 | !message || message[0] != ' ' || |
| 2244 | (message[1] != '+' && message[1] != '-') || |
| 2245 | !isdigit(message[2]) || !isdigit(message[3]) || |
| 2246 | !isdigit(message[4]) || !isdigit(message[5])) |
| 2247 | return 0; /* corrupt? */ |
| 2248 | email_end[1] = '\0'; |
| 2249 | tz = strtol(message + 1, NULL, 10); |
| 2250 | if (message[6] != '\t') |
| 2251 | message += 6; |
| 2252 | else |
| 2253 | message += 7; |
| 2254 | return fn(refname, &ooid, &noid, p, timestamp, tz, message, cb_data); |
| 2255 | } |
| 2256 | |
| 2257 | static char *find_beginning_of_line(char *bob, char *scan) |
| 2258 | { |
| 2259 | while (bob < scan && *(--scan) != '\n') |
| 2260 | ; /* keep scanning backwards */ |
| 2261 | /* |
| 2262 | * Return either beginning of the buffer, or LF at the end of |
| 2263 | * the previous line. |
| 2264 | */ |
| 2265 | return scan; |
| 2266 | } |
| 2267 | |
| 2268 | static int files_for_each_reflog_ent_reverse(struct ref_store *ref_store, |
| 2269 | const char *refname, |
| 2270 | each_reflog_ent_fn fn, |
| 2271 | void *cb_data) |
| 2272 | { |
| 2273 | struct files_ref_store *refs = |
| 2274 | files_downcast(ref_store, REF_STORE_READ, |
| 2275 | "for_each_reflog_ent_reverse"); |
| 2276 | struct strbuf sb = STRBUF_INIT; |
| 2277 | FILE *logfp; |
| 2278 | long pos; |
| 2279 | int ret = 0, at_tail = 1; |
| 2280 | |
| 2281 | files_reflog_path(refs, &sb, refname); |
| 2282 | logfp = fopen(sb.buf, "r"); |
| 2283 | strbuf_release(&sb); |
| 2284 | if (!logfp) |
| 2285 | return -1; |
| 2286 | |
| 2287 | /* Jump to the end */ |
| 2288 | if (fseek(logfp, 0, SEEK_END) < 0) |
| 2289 | ret = error("cannot seek back reflog for %s: %s", |
| 2290 | refname, strerror(errno)); |
| 2291 | pos = ftell(logfp); |
| 2292 | while (!ret && 0 < pos) { |
| 2293 | int cnt; |
| 2294 | size_t nread; |
| 2295 | char buf[BUFSIZ]; |
| 2296 | char *endp, *scanp; |
| 2297 | |
| 2298 | /* Fill next block from the end */ |
| 2299 | cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos; |
| 2300 | if (fseek(logfp, pos - cnt, SEEK_SET)) { |
| 2301 | ret = error("cannot seek back reflog for %s: %s", |
| 2302 | refname, strerror(errno)); |
| 2303 | break; |
| 2304 | } |
| 2305 | nread = fread(buf, cnt, 1, logfp); |
| 2306 | if (nread != 1) { |
| 2307 | ret = error("cannot read %d bytes from reflog for %s: %s", |
| 2308 | cnt, refname, strerror(errno)); |
| 2309 | break; |
| 2310 | } |
| 2311 | pos -= cnt; |
| 2312 | |
| 2313 | scanp = endp = buf + cnt; |
| 2314 | if (at_tail && scanp[-1] == '\n') |
| 2315 | /* Looking at the final LF at the end of the file */ |
| 2316 | scanp--; |
| 2317 | at_tail = 0; |
| 2318 | |
| 2319 | while (buf < scanp) { |
| 2320 | /* |
| 2321 | * terminating LF of the previous line, or the beginning |
| 2322 | * of the buffer. |
| 2323 | */ |
| 2324 | char *bp; |
| 2325 | |
| 2326 | bp = find_beginning_of_line(buf, scanp); |
| 2327 | |
| 2328 | if (*bp == '\n') { |
| 2329 | /* |
| 2330 | * The newline is the end of the previous line, |
| 2331 | * so we know we have complete line starting |
| 2332 | * at (bp + 1). Prefix it onto any prior data |
| 2333 | * we collected for the line and process it. |
| 2334 | */ |
| 2335 | strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1)); |
| 2336 | scanp = bp; |
| 2337 | endp = bp + 1; |
| 2338 | ret = show_one_reflog_ent(refs, refname, &sb, fn, cb_data); |
| 2339 | strbuf_reset(&sb); |
| 2340 | if (ret) |
| 2341 | break; |
| 2342 | } else if (!pos) { |
| 2343 | /* |
| 2344 | * We are at the start of the buffer, and the |
| 2345 | * start of the file; there is no previous |
| 2346 | * line, and we have everything for this one. |
| 2347 | * Process it, and we can end the loop. |
| 2348 | */ |
| 2349 | strbuf_splice(&sb, 0, 0, buf, endp - buf); |
| 2350 | ret = show_one_reflog_ent(refs, refname, &sb, fn, cb_data); |
| 2351 | strbuf_reset(&sb); |
| 2352 | break; |
| 2353 | } |
| 2354 | |
| 2355 | if (bp == buf) { |
| 2356 | /* |
| 2357 | * We are at the start of the buffer, and there |
| 2358 | * is more file to read backwards. Which means |
| 2359 | * we are in the middle of a line. Note that we |
| 2360 | * may get here even if *bp was a newline; that |
| 2361 | * just means we are at the exact end of the |
| 2362 | * previous line, rather than some spot in the |
| 2363 | * middle. |
| 2364 | * |
| 2365 | * Save away what we have to be combined with |
| 2366 | * the data from the next read. |
| 2367 | */ |
| 2368 | strbuf_splice(&sb, 0, 0, buf, endp - buf); |
| 2369 | break; |
| 2370 | } |
| 2371 | } |
| 2372 | |
| 2373 | } |
| 2374 | if (!ret && sb.len) |
| 2375 | BUG("reverse reflog parser had leftover data"); |
| 2376 | |
| 2377 | fclose(logfp); |
| 2378 | strbuf_release(&sb); |
| 2379 | return ret; |
| 2380 | } |
| 2381 | |
| 2382 | static int files_for_each_reflog_ent(struct ref_store *ref_store, |
| 2383 | const char *refname, |
| 2384 | each_reflog_ent_fn fn, void *cb_data) |
| 2385 | { |
| 2386 | struct files_ref_store *refs = |
| 2387 | files_downcast(ref_store, REF_STORE_READ, |
| 2388 | "for_each_reflog_ent"); |
| 2389 | FILE *logfp; |
| 2390 | struct strbuf sb = STRBUF_INIT; |
| 2391 | int ret = 0; |
| 2392 | |
| 2393 | files_reflog_path(refs, &sb, refname); |
| 2394 | logfp = fopen(sb.buf, "r"); |
| 2395 | strbuf_release(&sb); |
| 2396 | if (!logfp) |
| 2397 | return -1; |
| 2398 | |
| 2399 | while (!ret && !strbuf_getwholeline(&sb, logfp, '\n')) |
| 2400 | ret = show_one_reflog_ent(refs, refname, &sb, fn, cb_data); |
| 2401 | fclose(logfp); |
| 2402 | strbuf_release(&sb); |
| 2403 | return ret; |
| 2404 | } |
| 2405 | |
| 2406 | struct files_reflog_iterator { |
| 2407 | struct ref_iterator base; |
| 2408 | struct ref_store *ref_store; |
| 2409 | struct dir_iterator *dir_iterator; |
| 2410 | }; |
| 2411 | |
| 2412 | static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator) |
| 2413 | { |
| 2414 | struct files_reflog_iterator *iter = |
| 2415 | (struct files_reflog_iterator *)ref_iterator; |
| 2416 | struct dir_iterator *diter = iter->dir_iterator; |
| 2417 | int ok; |
| 2418 | |
| 2419 | while ((ok = dir_iterator_advance(diter)) == ITER_OK) { |
| 2420 | if (!S_ISREG(diter->st.st_mode)) |
| 2421 | continue; |
| 2422 | if (check_refname_format(diter->basename, |
| 2423 | REFNAME_ALLOW_ONELEVEL)) |
| 2424 | continue; |
| 2425 | |
| 2426 | iter->base.ref.name = diter->relative_path; |
| 2427 | return ITER_OK; |
| 2428 | } |
| 2429 | |
| 2430 | return ok; |
| 2431 | } |
| 2432 | |
| 2433 | static int files_reflog_iterator_seek(struct ref_iterator *ref_iterator UNUSED, |
| 2434 | const char *refname UNUSED, |
| 2435 | unsigned int flags UNUSED) |
| 2436 | { |
| 2437 | BUG("ref_iterator_seek() called for reflog_iterator"); |
| 2438 | } |
| 2439 | |
| 2440 | static void files_reflog_iterator_release(struct ref_iterator *ref_iterator) |
| 2441 | { |
| 2442 | struct files_reflog_iterator *iter = |
| 2443 | (struct files_reflog_iterator *)ref_iterator; |
| 2444 | dir_iterator_free(iter->dir_iterator); |
| 2445 | } |
| 2446 | |
| 2447 | static struct ref_iterator_vtable files_reflog_iterator_vtable = { |
| 2448 | .advance = files_reflog_iterator_advance, |
| 2449 | .seek = files_reflog_iterator_seek, |
| 2450 | .release = files_reflog_iterator_release, |
| 2451 | }; |
| 2452 | |
| 2453 | static struct ref_iterator *reflog_iterator_begin(struct ref_store *ref_store, |
| 2454 | const char *gitdir) |
| 2455 | { |
| 2456 | struct dir_iterator *diter; |
| 2457 | struct files_reflog_iterator *iter; |
| 2458 | struct ref_iterator *ref_iterator; |
| 2459 | struct strbuf sb = STRBUF_INIT; |
| 2460 | |
| 2461 | strbuf_addf(&sb, "%s/logs", gitdir); |
| 2462 | |
| 2463 | diter = dir_iterator_begin(sb.buf, DIR_ITERATOR_SORTED); |
| 2464 | if (!diter) { |
| 2465 | strbuf_release(&sb); |
| 2466 | return empty_ref_iterator_begin(); |
| 2467 | } |
| 2468 | |
| 2469 | CALLOC_ARRAY(iter, 1); |
| 2470 | ref_iterator = &iter->base; |
| 2471 | |
| 2472 | base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable); |
| 2473 | iter->dir_iterator = diter; |
| 2474 | iter->ref_store = ref_store; |
| 2475 | strbuf_release(&sb); |
| 2476 | |
| 2477 | return ref_iterator; |
| 2478 | } |
| 2479 | |
| 2480 | static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_store) |
| 2481 | { |
| 2482 | struct files_ref_store *refs = |
| 2483 | files_downcast(ref_store, REF_STORE_READ, |
| 2484 | "reflog_iterator_begin"); |
| 2485 | |
| 2486 | if (!strcmp(refs->base.gitdir, refs->gitcommondir)) { |
| 2487 | return reflog_iterator_begin(ref_store, refs->gitcommondir); |
| 2488 | } else { |
| 2489 | return merge_ref_iterator_begin( |
| 2490 | reflog_iterator_begin(ref_store, refs->base.gitdir), |
| 2491 | reflog_iterator_begin(ref_store, refs->gitcommondir), |
| 2492 | ref_iterator_select, refs); |
| 2493 | } |
| 2494 | } |
| 2495 | |
| 2496 | /* |
| 2497 | * If update is a direct update of head_ref (the reference pointed to |
| 2498 | * by HEAD), then add an extra REF_LOG_ONLY update for HEAD. |
| 2499 | */ |
| 2500 | static enum ref_transaction_error split_head_update(struct ref_update *update, |
| 2501 | struct ref_transaction *transaction, |
| 2502 | const char *head_ref, |
| 2503 | struct strbuf *err) |
| 2504 | { |
| 2505 | struct ref_update *new_update; |
| 2506 | |
| 2507 | if ((update->flags & REF_LOG_ONLY) || |
| 2508 | (update->flags & REF_SKIP_CREATE_REFLOG) || |
| 2509 | (update->flags & REF_IS_PRUNING) || |
| 2510 | (update->flags & REF_UPDATE_VIA_HEAD)) |
| 2511 | return 0; |
| 2512 | |
| 2513 | if (strcmp(update->refname, head_ref)) |
| 2514 | return 0; |
| 2515 | |
| 2516 | /* |
| 2517 | * First make sure that HEAD is not already in the |
| 2518 | * transaction. This check is O(lg N) in the transaction |
| 2519 | * size, but it happens at most once per transaction. |
| 2520 | */ |
| 2521 | if (string_list_has_string(&transaction->refnames, "HEAD")) { |
| 2522 | /* An entry already existed */ |
| 2523 | strbuf_addf(err, |
| 2524 | "multiple updates for 'HEAD' (including one " |
| 2525 | "via its referent '%s') are not allowed", |
| 2526 | update->refname); |
| 2527 | return REF_TRANSACTION_ERROR_NAME_CONFLICT; |
| 2528 | } |
| 2529 | |
| 2530 | new_update = ref_transaction_add_update( |
| 2531 | transaction, "HEAD", |
| 2532 | update->flags | REF_LOG_ONLY | REF_NO_DEREF | REF_LOG_VIA_SPLIT, |
| 2533 | &update->new_oid, &update->old_oid, &update->peeled, |
| 2534 | NULL, NULL, update->committer_info, update->msg); |
| 2535 | new_update->parent_update = update; |
| 2536 | |
| 2537 | /* |
| 2538 | * Add "HEAD". This insertion is O(N) in the transaction |
| 2539 | * size, but it happens at most once per transaction. |
| 2540 | * Add new_update->refname instead of a literal "HEAD". |
| 2541 | */ |
| 2542 | if (strcmp(new_update->refname, "HEAD")) |
| 2543 | BUG("%s unexpectedly not 'HEAD'", new_update->refname); |
| 2544 | |
| 2545 | return 0; |
| 2546 | } |
| 2547 | |
| 2548 | /* |
| 2549 | * update is for a symref that points at referent and doesn't have |
| 2550 | * REF_NO_DEREF set. Split it into two updates: |
| 2551 | * - The original update, but with REF_LOG_ONLY and REF_NO_DEREF set |
| 2552 | * - A new, separate update for the referent reference |
| 2553 | * Note that the new update will itself be subject to splitting when |
| 2554 | * the iteration gets to it. |
| 2555 | */ |
| 2556 | static enum ref_transaction_error split_symref_update(struct ref_update *update, |
| 2557 | const char *referent, |
| 2558 | struct ref_transaction *transaction, |
| 2559 | struct strbuf *err) |
| 2560 | { |
| 2561 | struct ref_update *new_update; |
| 2562 | unsigned int new_flags; |
| 2563 | |
| 2564 | /* |
| 2565 | * First make sure that referent is not already in the |
| 2566 | * transaction. This check is O(lg N) in the transaction |
| 2567 | * size, but it happens at most once per symref in a |
| 2568 | * transaction. |
| 2569 | */ |
| 2570 | if (string_list_has_string(&transaction->refnames, referent)) { |
| 2571 | /* An entry already exists */ |
| 2572 | strbuf_addf(err, |
| 2573 | "multiple updates for '%s' (including one " |
| 2574 | "via symref '%s') are not allowed", |
| 2575 | referent, update->refname); |
| 2576 | return REF_TRANSACTION_ERROR_NAME_CONFLICT; |
| 2577 | } |
| 2578 | |
| 2579 | new_flags = update->flags; |
| 2580 | if (!strcmp(update->refname, "HEAD")) { |
| 2581 | /* |
| 2582 | * Record that the new update came via HEAD, so that |
| 2583 | * when we process it, split_head_update() doesn't try |
| 2584 | * to add another reflog update for HEAD. Note that |
| 2585 | * this bit will be propagated if the new_update |
| 2586 | * itself needs to be split. |
| 2587 | */ |
| 2588 | new_flags |= REF_UPDATE_VIA_HEAD; |
| 2589 | } |
| 2590 | |
| 2591 | new_update = ref_transaction_add_update( |
| 2592 | transaction, referent, new_flags, |
| 2593 | update->new_target ? NULL : &update->new_oid, |
| 2594 | update->old_target ? NULL : &update->old_oid, |
| 2595 | &update->peeled, update->new_target, update->old_target, |
| 2596 | NULL, update->msg); |
| 2597 | |
| 2598 | new_update->parent_update = update; |
| 2599 | |
| 2600 | /* |
| 2601 | * Change the symbolic ref update to log only. Also, it |
| 2602 | * doesn't need to check its old OID value, as that will be |
| 2603 | * done when new_update is processed. |
| 2604 | */ |
| 2605 | update->flags |= REF_LOG_ONLY | REF_NO_DEREF; |
| 2606 | |
| 2607 | return 0; |
| 2608 | } |
| 2609 | |
| 2610 | /* |
| 2611 | * Check whether the REF_HAVE_OLD and old_oid values stored in update |
| 2612 | * are consistent with oid, which is the reference's current value. If |
| 2613 | * everything is OK, return 0; otherwise, write an error message to |
| 2614 | * err and return -1. |
| 2615 | */ |
| 2616 | static enum ref_transaction_error check_old_oid(struct ref_update *update, |
| 2617 | struct object_id *oid, |
| 2618 | struct strbuf *referent, |
| 2619 | struct strbuf *err) |
| 2620 | { |
| 2621 | if (update->flags & REF_LOG_ONLY || |
| 2622 | !(update->flags & REF_HAVE_OLD)) |
| 2623 | return 0; |
| 2624 | |
| 2625 | if (oideq(oid, &update->old_oid)) { |
| 2626 | /* |
| 2627 | * Normally matching the expected old oid is enough. Either we |
| 2628 | * found the ref at the expected state, or we are creating and |
| 2629 | * expect the null oid (and likewise found nothing). |
| 2630 | * |
| 2631 | * But there is one exception for the null oid: if we found a |
| 2632 | * symref pointing to nothing we'll also get the null oid. In |
| 2633 | * regular recursive mode, that's good (we'll write to what the |
| 2634 | * symref points to, which doesn't exist). But in no-deref |
| 2635 | * mode, it means we'll clobber the symref, even though the |
| 2636 | * caller asked for this to be a creation event. So flag |
| 2637 | * that case to preserve the dangling symref. |
| 2638 | */ |
| 2639 | if ((update->flags & REF_NO_DEREF) && referent->len && |
| 2640 | is_null_oid(oid)) { |
| 2641 | strbuf_addf(err, "cannot lock ref '%s': " |
| 2642 | "dangling symref already exists", |
| 2643 | ref_update_original_update_refname(update)); |
| 2644 | return REF_TRANSACTION_ERROR_CREATE_EXISTS; |
| 2645 | } |
| 2646 | return 0; |
| 2647 | } |
| 2648 | |
| 2649 | if (is_null_oid(&update->old_oid)) { |
| 2650 | strbuf_addf(err, "cannot lock ref '%s': " |
| 2651 | "reference already exists", |
| 2652 | ref_update_original_update_refname(update)); |
| 2653 | return REF_TRANSACTION_ERROR_CREATE_EXISTS; |
| 2654 | } else if (is_null_oid(oid)) { |
| 2655 | strbuf_addf(err, "cannot lock ref '%s': " |
| 2656 | "reference is missing but expected %s", |
| 2657 | ref_update_original_update_refname(update), |
| 2658 | oid_to_hex(&update->old_oid)); |
| 2659 | return REF_TRANSACTION_ERROR_NONEXISTENT_REF; |
| 2660 | } |
| 2661 | |
| 2662 | strbuf_addf(err, "cannot lock ref '%s': is at %s but expected %s", |
| 2663 | ref_update_original_update_refname(update), oid_to_hex(oid), |
| 2664 | oid_to_hex(&update->old_oid)); |
| 2665 | |
| 2666 | return REF_TRANSACTION_ERROR_INCORRECT_OLD_VALUE; |
| 2667 | } |
| 2668 | |
| 2669 | struct files_transaction_backend_data { |
| 2670 | struct ref_transaction *packed_transaction; |
| 2671 | int packed_refs_locked; |
| 2672 | struct strmap ref_locks; |
| 2673 | }; |
| 2674 | |
| 2675 | /* |
| 2676 | * Prepare for carrying out update: |
| 2677 | * - Lock the reference referred to by update. |
| 2678 | * - Read the reference under lock. |
| 2679 | * - Check that its old OID value (if specified) is correct, and in |
| 2680 | * any case record it in update->lock->old_oid for later use when |
| 2681 | * writing the reflog. |
| 2682 | * - If it is a symref update without REF_NO_DEREF, split it up into a |
| 2683 | * REF_LOG_ONLY update of the symref and add a separate update for |
| 2684 | * the referent to transaction. |
| 2685 | * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY |
| 2686 | * update of HEAD. |
| 2687 | */ |
| 2688 | static enum ref_transaction_error lock_ref_for_update(struct files_ref_store *refs, |
| 2689 | struct ref_update *update, |
| 2690 | size_t update_idx, |
| 2691 | struct ref_transaction *transaction, |
| 2692 | const char *head_ref, |
| 2693 | struct string_list *refnames_to_check, |
| 2694 | struct strbuf *err) |
| 2695 | { |
| 2696 | struct strbuf referent = STRBUF_INIT; |
| 2697 | int mustexist = ref_update_expects_existing_old_ref(update); |
| 2698 | struct files_transaction_backend_data *backend_data; |
| 2699 | enum ref_transaction_error ret = 0; |
| 2700 | struct ref_lock *lock; |
| 2701 | |
| 2702 | files_assert_main_repository(refs, "lock_ref_for_update"); |
| 2703 | |
| 2704 | backend_data = transaction->backend_data; |
| 2705 | |
| 2706 | if ((update->flags & REF_HAVE_NEW) && ref_update_has_null_new_value(update)) |
| 2707 | update->flags |= REF_DELETING; |
| 2708 | |
| 2709 | if (head_ref) { |
| 2710 | ret = split_head_update(update, transaction, head_ref, err); |
| 2711 | if (ret) |
| 2712 | goto out; |
| 2713 | } |
| 2714 | |
| 2715 | lock = strmap_get(&backend_data->ref_locks, update->refname); |
| 2716 | if (lock) { |
| 2717 | lock->count++; |
| 2718 | } else { |
| 2719 | ret = lock_raw_ref(refs, transaction, update_idx, mustexist, |
| 2720 | refnames_to_check, &lock, &referent, err); |
| 2721 | if (ret) { |
| 2722 | char *reason; |
| 2723 | |
| 2724 | reason = strbuf_detach(err, NULL); |
| 2725 | strbuf_addf(err, "cannot lock ref '%s': %s", |
| 2726 | ref_update_original_update_refname(update), reason); |
| 2727 | free(reason); |
| 2728 | goto out; |
| 2729 | } |
| 2730 | |
| 2731 | strmap_put(&backend_data->ref_locks, update->refname, lock); |
| 2732 | } |
| 2733 | |
| 2734 | update->backend_data = lock; |
| 2735 | |
| 2736 | if (update->flags & REF_LOG_VIA_SPLIT) { |
| 2737 | struct ref_lock *parent_lock; |
| 2738 | |
| 2739 | if (!update->parent_update) |
| 2740 | BUG("split update without a parent"); |
| 2741 | |
| 2742 | parent_lock = update->parent_update->backend_data; |
| 2743 | |
| 2744 | /* |
| 2745 | * Check that "HEAD" didn't racily change since we have looked |
| 2746 | * it up. If it did we must refuse to write the reflog entry. |
| 2747 | * |
| 2748 | * Note that this does not catch all races: if "HEAD" was |
| 2749 | * racily changed to point to one of the refs part of the |
| 2750 | * transaction then we would miss writing the split reflog |
| 2751 | * entry for "HEAD". |
| 2752 | */ |
| 2753 | if (!(update->type & REF_ISSYMREF) || |
| 2754 | strcmp(update->parent_update->refname, referent.buf)) { |
| 2755 | strbuf_addstr(err, "HEAD has been racily updated"); |
| 2756 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 2757 | goto out; |
| 2758 | } |
| 2759 | |
| 2760 | if (update->flags & REF_HAVE_OLD) { |
| 2761 | oidcpy(&lock->old_oid, &update->old_oid); |
| 2762 | } else { |
| 2763 | oidcpy(&lock->old_oid, &parent_lock->old_oid); |
| 2764 | } |
| 2765 | } else if (update->type & REF_ISSYMREF) { |
| 2766 | if (update->flags & REF_NO_DEREF) { |
| 2767 | /* |
| 2768 | * We won't be reading the referent as part of |
| 2769 | * the transaction, so we have to read it here |
| 2770 | * to record and possibly check old_oid: |
| 2771 | */ |
| 2772 | if (!refs_resolve_ref_unsafe(&refs->base, |
| 2773 | referent.buf, 0, |
| 2774 | &lock->old_oid, NULL)) { |
| 2775 | if (update->flags & REF_HAVE_OLD) { |
| 2776 | strbuf_addf(err, "cannot lock ref '%s': " |
| 2777 | "error reading reference", |
| 2778 | ref_update_original_update_refname(update)); |
| 2779 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 2780 | goto out; |
| 2781 | } |
| 2782 | } |
| 2783 | |
| 2784 | if (update->old_target) |
| 2785 | ret = ref_update_check_old_target(referent.buf, update, err); |
| 2786 | else |
| 2787 | ret = check_old_oid(update, &lock->old_oid, |
| 2788 | &referent, err); |
| 2789 | if (ret) |
| 2790 | goto out; |
| 2791 | } else { |
| 2792 | /* |
| 2793 | * Create a new update for the reference this |
| 2794 | * symref is pointing at. Also, we will record |
| 2795 | * and verify old_oid for this update as part |
| 2796 | * of processing the split-off update, so we |
| 2797 | * don't have to do it here. |
| 2798 | */ |
| 2799 | ret = split_symref_update(update, referent.buf, |
| 2800 | transaction, err); |
| 2801 | if (ret) |
| 2802 | goto out; |
| 2803 | } |
| 2804 | } else { |
| 2805 | struct ref_update *parent_update; |
| 2806 | |
| 2807 | /* |
| 2808 | * Even if the ref is a regular ref, if `old_target` is set, we |
| 2809 | * fail with an error. |
| 2810 | */ |
| 2811 | if (update->old_target) { |
| 2812 | strbuf_addf(err, _("cannot lock ref '%s': " |
| 2813 | "expected symref with target '%s': " |
| 2814 | "but is a regular ref"), |
| 2815 | ref_update_original_update_refname(update), |
| 2816 | update->old_target); |
| 2817 | ret = REF_TRANSACTION_ERROR_EXPECTED_SYMREF; |
| 2818 | goto out; |
| 2819 | } else { |
| 2820 | ret = check_old_oid(update, &lock->old_oid, |
| 2821 | &referent, err); |
| 2822 | if (ret) { |
| 2823 | goto out; |
| 2824 | } |
| 2825 | } |
| 2826 | |
| 2827 | /* |
| 2828 | * If this update is happening indirectly because of a |
| 2829 | * symref update, record the old OID in the parent |
| 2830 | * update: |
| 2831 | */ |
| 2832 | for (parent_update = update->parent_update; |
| 2833 | parent_update; |
| 2834 | parent_update = parent_update->parent_update) { |
| 2835 | struct ref_lock *parent_lock = parent_update->backend_data; |
| 2836 | oidcpy(&parent_lock->old_oid, &lock->old_oid); |
| 2837 | } |
| 2838 | } |
| 2839 | |
| 2840 | if (update->new_target && !(update->flags & REF_LOG_ONLY)) { |
| 2841 | if (create_symref_lock(lock, update->new_target, err)) { |
| 2842 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 2843 | goto out; |
| 2844 | } |
| 2845 | |
| 2846 | if (close_ref_gently(lock)) { |
| 2847 | strbuf_addf(err, "couldn't close '%s.lock'", |
| 2848 | update->refname); |
| 2849 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 2850 | goto out; |
| 2851 | } |
| 2852 | |
| 2853 | /* |
| 2854 | * Once we have created the symref lock, the commit |
| 2855 | * phase of the transaction only needs to commit the lock. |
| 2856 | */ |
| 2857 | update->flags |= REF_NEEDS_COMMIT; |
| 2858 | } else if ((update->flags & REF_HAVE_NEW) && |
| 2859 | !(update->flags & REF_DELETING) && |
| 2860 | !(update->flags & REF_LOG_ONLY)) { |
| 2861 | if (!(update->type & REF_ISSYMREF) && |
| 2862 | oideq(&lock->old_oid, &update->new_oid)) { |
| 2863 | /* |
| 2864 | * The reference already has the desired |
| 2865 | * value, so we don't need to write it. |
| 2866 | */ |
| 2867 | } else { |
| 2868 | ret = write_ref_to_lockfile( |
| 2869 | refs, lock, &update->new_oid, |
| 2870 | err); |
| 2871 | if (ret) { |
| 2872 | char *write_err = strbuf_detach(err, NULL); |
| 2873 | |
| 2874 | /* |
| 2875 | * The lock was freed upon failure of |
| 2876 | * write_ref_to_lockfile(): |
| 2877 | */ |
| 2878 | update->backend_data = NULL; |
| 2879 | strbuf_addf(err, |
| 2880 | "cannot update ref '%s': %s", |
| 2881 | update->refname, write_err); |
| 2882 | free(write_err); |
| 2883 | goto out; |
| 2884 | } else { |
| 2885 | update->flags |= REF_NEEDS_COMMIT; |
| 2886 | } |
| 2887 | } |
| 2888 | } |
| 2889 | if (!(update->flags & REF_NEEDS_COMMIT)) { |
| 2890 | /* |
| 2891 | * We didn't call write_ref_to_lockfile(), so |
| 2892 | * the lockfile is still open. Close it to |
| 2893 | * free up the file descriptor: |
| 2894 | */ |
| 2895 | if (close_ref_gently(lock)) { |
| 2896 | strbuf_addf(err, "couldn't close '%s.lock'", |
| 2897 | update->refname); |
| 2898 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 2899 | goto out; |
| 2900 | } |
| 2901 | } |
| 2902 | |
| 2903 | out: |
| 2904 | strbuf_release(&referent); |
| 2905 | return ret; |
| 2906 | } |
| 2907 | |
| 2908 | /* |
| 2909 | * Unlock any references in `transaction` that are still locked, and |
| 2910 | * mark the transaction closed. |
| 2911 | */ |
| 2912 | static void files_transaction_cleanup(struct files_ref_store *refs, |
| 2913 | struct ref_transaction *transaction) |
| 2914 | { |
| 2915 | size_t i; |
| 2916 | struct files_transaction_backend_data *backend_data = |
| 2917 | transaction->backend_data; |
| 2918 | struct strbuf err = STRBUF_INIT; |
| 2919 | |
| 2920 | for (i = 0; i < transaction->nr; i++) { |
| 2921 | struct ref_update *update = transaction->updates[i]; |
| 2922 | struct ref_lock *lock = update->backend_data; |
| 2923 | |
| 2924 | if (lock) { |
| 2925 | unlock_ref(lock); |
| 2926 | try_remove_empty_parents(refs, update->refname, |
| 2927 | REMOVE_EMPTY_PARENTS_REF); |
| 2928 | update->backend_data = NULL; |
| 2929 | } |
| 2930 | } |
| 2931 | |
| 2932 | if (backend_data) { |
| 2933 | if (backend_data->packed_transaction && |
| 2934 | ref_transaction_abort(backend_data->packed_transaction, &err)) { |
| 2935 | error("error aborting transaction: %s", err.buf); |
| 2936 | strbuf_release(&err); |
| 2937 | } |
| 2938 | |
| 2939 | if (backend_data->packed_refs_locked) |
| 2940 | packed_refs_unlock(refs->packed_ref_store); |
| 2941 | |
| 2942 | strmap_clear(&backend_data->ref_locks, 0); |
| 2943 | |
| 2944 | free(backend_data); |
| 2945 | } |
| 2946 | |
| 2947 | transaction->state = REF_TRANSACTION_CLOSED; |
| 2948 | } |
| 2949 | |
| 2950 | static int files_transaction_prepare(struct ref_store *ref_store, |
| 2951 | struct ref_transaction *transaction, |
| 2952 | struct strbuf *err) |
| 2953 | { |
| 2954 | struct files_ref_store *refs = |
| 2955 | files_downcast(ref_store, REF_STORE_WRITE, |
| 2956 | "ref_transaction_prepare"); |
| 2957 | size_t i; |
| 2958 | int ret = 0; |
| 2959 | struct string_list refnames_to_check = STRING_LIST_INIT_DUP; |
| 2960 | char *head_ref = NULL; |
| 2961 | int head_type; |
| 2962 | struct files_transaction_backend_data *backend_data; |
| 2963 | struct ref_transaction *packed_transaction = NULL; |
| 2964 | |
| 2965 | assert(err); |
| 2966 | |
| 2967 | if (transaction->flags & REF_TRANSACTION_FLAG_INITIAL) |
| 2968 | goto cleanup; |
| 2969 | if (!transaction->nr) |
| 2970 | goto cleanup; |
| 2971 | |
| 2972 | CALLOC_ARRAY(backend_data, 1); |
| 2973 | strmap_init(&backend_data->ref_locks); |
| 2974 | transaction->backend_data = backend_data; |
| 2975 | |
| 2976 | /* |
| 2977 | * Fail if any of the updates use REF_IS_PRUNING without REF_NO_DEREF. |
| 2978 | */ |
| 2979 | for (i = 0; i < transaction->nr; i++) { |
| 2980 | struct ref_update *update = transaction->updates[i]; |
| 2981 | |
| 2982 | if ((update->flags & REF_IS_PRUNING) && |
| 2983 | !(update->flags & REF_NO_DEREF)) |
| 2984 | BUG("REF_IS_PRUNING set without REF_NO_DEREF"); |
| 2985 | } |
| 2986 | |
| 2987 | /* |
| 2988 | * Special hack: If a branch is updated directly and HEAD |
| 2989 | * points to it (may happen on the remote side of a push |
| 2990 | * for example) then logically the HEAD reflog should be |
| 2991 | * updated too. |
| 2992 | * |
| 2993 | * A generic solution would require reverse symref lookups, |
| 2994 | * but finding all symrefs pointing to a given branch would be |
| 2995 | * rather costly for this rare event (the direct update of a |
| 2996 | * branch) to be worth it. So let's cheat and check with HEAD |
| 2997 | * only, which should cover 99% of all usage scenarios (even |
| 2998 | * 100% of the default ones). |
| 2999 | * |
| 3000 | * So if HEAD is a symbolic reference, then record the name of |
| 3001 | * the reference that it points to. If we see an update of |
| 3002 | * head_ref within the transaction, then split_head_update() |
| 3003 | * arranges for the reflog of HEAD to be updated, too. |
| 3004 | */ |
| 3005 | head_ref = refs_resolve_refdup(ref_store, "HEAD", |
| 3006 | RESOLVE_REF_NO_RECURSE, |
| 3007 | NULL, &head_type); |
| 3008 | |
| 3009 | if (head_ref && !(head_type & REF_ISSYMREF)) { |
| 3010 | FREE_AND_NULL(head_ref); |
| 3011 | } |
| 3012 | |
| 3013 | /* |
| 3014 | * Acquire all locks, verify old values if provided, check |
| 3015 | * that new values are valid, and write new values to the |
| 3016 | * lockfiles, ready to be activated. Only keep one lockfile |
| 3017 | * open at a time to avoid running out of file descriptors. |
| 3018 | * Note that lock_ref_for_update() might append more updates |
| 3019 | * to the transaction. |
| 3020 | */ |
| 3021 | for (i = 0; i < transaction->nr; i++) { |
| 3022 | struct ref_update *update = transaction->updates[i]; |
| 3023 | |
| 3024 | ret = lock_ref_for_update(refs, update, i, transaction, |
| 3025 | head_ref, &refnames_to_check, |
| 3026 | err); |
| 3027 | if (ret) { |
| 3028 | if (ref_transaction_maybe_set_rejected(transaction, i, |
| 3029 | ret, err)) { |
| 3030 | ret = 0; |
| 3031 | continue; |
| 3032 | } |
| 3033 | goto cleanup; |
| 3034 | } |
| 3035 | |
| 3036 | if (update->flags & REF_DELETING && |
| 3037 | !(update->flags & REF_LOG_ONLY) && |
| 3038 | !(update->flags & REF_IS_PRUNING)) { |
| 3039 | /* |
| 3040 | * This reference has to be deleted from |
| 3041 | * packed-refs if it exists there. |
| 3042 | */ |
| 3043 | if (!packed_transaction) { |
| 3044 | packed_transaction = ref_store_transaction_begin( |
| 3045 | refs->packed_ref_store, |
| 3046 | transaction->flags, err); |
| 3047 | if (!packed_transaction) { |
| 3048 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3049 | goto cleanup; |
| 3050 | } |
| 3051 | |
| 3052 | backend_data->packed_transaction = |
| 3053 | packed_transaction; |
| 3054 | } |
| 3055 | |
| 3056 | ref_transaction_add_update( |
| 3057 | packed_transaction, update->refname, |
| 3058 | REF_HAVE_NEW | REF_NO_DEREF, |
| 3059 | &update->new_oid, NULL, NULL, |
| 3060 | NULL, NULL, NULL, NULL); |
| 3061 | } |
| 3062 | } |
| 3063 | |
| 3064 | /* |
| 3065 | * Verify that none of the loose reference that we're about to write |
| 3066 | * conflict with any existing packed references. Ideally, we'd do this |
| 3067 | * check after the packed-refs are locked so that the file cannot |
| 3068 | * change underneath our feet. But introducing such a lock now would |
| 3069 | * probably do more harm than good as users rely on there not being a |
| 3070 | * global lock with the "files" backend. |
| 3071 | * |
| 3072 | * Another alternative would be to do the check after the (optional) |
| 3073 | * lock, but that would extend the time we spend in the globally-locked |
| 3074 | * state. |
| 3075 | * |
| 3076 | * So instead, we accept the race for now. |
| 3077 | */ |
| 3078 | if (refs_verify_refnames_available(refs->packed_ref_store, &refnames_to_check, |
| 3079 | &transaction->refnames, NULL, transaction, |
| 3080 | 0, err)) { |
| 3081 | ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; |
| 3082 | goto cleanup; |
| 3083 | } |
| 3084 | |
| 3085 | if (packed_transaction) { |
| 3086 | if (packed_refs_lock(refs->packed_ref_store, 0, err)) { |
| 3087 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3088 | goto cleanup; |
| 3089 | } |
| 3090 | backend_data->packed_refs_locked = 1; |
| 3091 | |
| 3092 | if (is_packed_transaction_needed(refs->packed_ref_store, |
| 3093 | packed_transaction)) { |
| 3094 | ret = ref_transaction_prepare(packed_transaction, err); |
| 3095 | /* |
| 3096 | * A failure during the prepare step will abort |
| 3097 | * itself, but not free. Do that now, and disconnect |
| 3098 | * from the files_transaction so it does not try to |
| 3099 | * abort us when we hit the cleanup code below. |
| 3100 | */ |
| 3101 | if (ret) { |
| 3102 | ref_transaction_free(packed_transaction); |
| 3103 | backend_data->packed_transaction = NULL; |
| 3104 | } |
| 3105 | } else { |
| 3106 | /* |
| 3107 | * We can skip rewriting the `packed-refs` |
| 3108 | * file. But we do need to leave it locked, so |
| 3109 | * that somebody else doesn't pack a reference |
| 3110 | * that we are trying to delete. |
| 3111 | * |
| 3112 | * We need to disconnect our transaction from |
| 3113 | * backend_data, since the abort (whether successful or |
| 3114 | * not) will free it. |
| 3115 | */ |
| 3116 | backend_data->packed_transaction = NULL; |
| 3117 | if (ref_transaction_abort(packed_transaction, err)) { |
| 3118 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3119 | goto cleanup; |
| 3120 | } |
| 3121 | } |
| 3122 | } |
| 3123 | |
| 3124 | cleanup: |
| 3125 | free(head_ref); |
| 3126 | string_list_clear(&refnames_to_check, 1); |
| 3127 | |
| 3128 | if (ret) |
| 3129 | files_transaction_cleanup(refs, transaction); |
| 3130 | else |
| 3131 | transaction->state = REF_TRANSACTION_PREPARED; |
| 3132 | |
| 3133 | return ret; |
| 3134 | } |
| 3135 | |
| 3136 | static int parse_and_write_reflog(struct files_ref_store *refs, |
| 3137 | struct ref_update *update, |
| 3138 | struct ref_lock *lock, |
| 3139 | struct strbuf *err) |
| 3140 | { |
| 3141 | struct object_id *old_oid = &lock->old_oid; |
| 3142 | |
| 3143 | if (update->flags & REF_LOG_USE_PROVIDED_OIDS) { |
| 3144 | if (!(update->flags & REF_HAVE_OLD) || |
| 3145 | !(update->flags & REF_HAVE_NEW) || |
| 3146 | !(update->flags & REF_LOG_ONLY)) { |
| 3147 | strbuf_addf(err, _("trying to write reflog for '%s' " |
| 3148 | "with incomplete values"), update->refname); |
| 3149 | return REF_TRANSACTION_ERROR_GENERIC; |
| 3150 | } |
| 3151 | |
| 3152 | old_oid = &update->old_oid; |
| 3153 | } |
| 3154 | |
| 3155 | if (update->new_target) { |
| 3156 | /* |
| 3157 | * We want to get the resolved OID for the target, to ensure |
| 3158 | * that the correct value is added to the reflog. |
| 3159 | */ |
| 3160 | if (!refs_resolve_ref_unsafe(&refs->base, update->new_target, |
| 3161 | RESOLVE_REF_READING, |
| 3162 | &update->new_oid, NULL)) { |
| 3163 | /* |
| 3164 | * TODO: currently we skip creating reflogs for dangling |
| 3165 | * symref updates. It would be nice to capture this as |
| 3166 | * zero oid updates however. |
| 3167 | */ |
| 3168 | return 0; |
| 3169 | } |
| 3170 | } |
| 3171 | |
| 3172 | if (files_log_ref_write(refs, lock->ref_name, old_oid, |
| 3173 | &update->new_oid, update->committer_info, |
| 3174 | update->msg, update->flags, err)) { |
| 3175 | char *old_msg = strbuf_detach(err, NULL); |
| 3176 | |
| 3177 | strbuf_addf(err, "cannot update the ref '%s': %s", |
| 3178 | lock->ref_name, old_msg); |
| 3179 | free(old_msg); |
| 3180 | unlock_ref(lock); |
| 3181 | update->backend_data = NULL; |
| 3182 | return -1; |
| 3183 | } |
| 3184 | |
| 3185 | return 0; |
| 3186 | } |
| 3187 | |
| 3188 | static int ref_present(const struct reference *ref, void *cb_data) |
| 3189 | { |
| 3190 | struct string_list *affected_refnames = cb_data; |
| 3191 | |
| 3192 | return string_list_has_string(affected_refnames, ref->name); |
| 3193 | } |
| 3194 | |
| 3195 | static int files_transaction_finish_initial(struct files_ref_store *refs, |
| 3196 | struct ref_transaction *transaction, |
| 3197 | struct strbuf *err) |
| 3198 | { |
| 3199 | struct refs_for_each_ref_options opts = { |
| 3200 | .flags = REFS_FOR_EACH_INCLUDE_BROKEN, |
| 3201 | }; |
| 3202 | size_t i; |
| 3203 | int ret = 0; |
| 3204 | struct string_list affected_refnames = STRING_LIST_INIT_NODUP; |
| 3205 | struct string_list refnames_to_check = STRING_LIST_INIT_NODUP; |
| 3206 | struct ref_transaction *packed_transaction = NULL; |
| 3207 | struct ref_transaction *loose_transaction = NULL; |
| 3208 | |
| 3209 | assert(err); |
| 3210 | |
| 3211 | if (transaction->state != REF_TRANSACTION_PREPARED) |
| 3212 | BUG("commit called for transaction that is not prepared"); |
| 3213 | |
| 3214 | /* |
| 3215 | * It's really undefined to call this function in an active |
| 3216 | * repository or when there are existing references: we are |
| 3217 | * only locking and changing packed-refs, so (1) any |
| 3218 | * simultaneous processes might try to change a reference at |
| 3219 | * the same time we do, and (2) any existing loose versions of |
| 3220 | * the references that we are setting would have precedence |
| 3221 | * over our values. But some remote helpers create the remote |
| 3222 | * "HEAD" and "master" branches before calling this function, |
| 3223 | * so here we really only check that none of the references |
| 3224 | * that we are creating already exists. |
| 3225 | */ |
| 3226 | if (refs_for_each_ref_ext(&refs->base, ref_present, |
| 3227 | &transaction->refnames, &opts)) |
| 3228 | BUG("initial ref transaction called with existing refs"); |
| 3229 | |
| 3230 | packed_transaction = ref_store_transaction_begin(refs->packed_ref_store, |
| 3231 | transaction->flags, err); |
| 3232 | if (!packed_transaction) { |
| 3233 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3234 | goto cleanup; |
| 3235 | } |
| 3236 | |
| 3237 | for (i = 0; i < transaction->nr; i++) { |
| 3238 | struct ref_update *update = transaction->updates[i]; |
| 3239 | |
| 3240 | if (!(update->flags & REF_LOG_ONLY) && |
| 3241 | (update->flags & REF_HAVE_OLD) && |
| 3242 | !is_null_oid(&update->old_oid)) |
| 3243 | BUG("initial ref transaction with old_sha1 set"); |
| 3244 | |
| 3245 | string_list_append(&refnames_to_check, update->refname); |
| 3246 | |
| 3247 | /* |
| 3248 | * packed-refs don't support symbolic refs, root refs and reflogs, |
| 3249 | * so we have to queue these references via the loose transaction. |
| 3250 | */ |
| 3251 | if (update->new_target || |
| 3252 | is_root_ref(update->refname) || |
| 3253 | (update->flags & REF_LOG_ONLY)) { |
| 3254 | if (!loose_transaction) { |
| 3255 | loose_transaction = ref_store_transaction_begin(&refs->base, 0, err); |
| 3256 | if (!loose_transaction) { |
| 3257 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3258 | goto cleanup; |
| 3259 | } |
| 3260 | } |
| 3261 | |
| 3262 | if (update->flags & REF_LOG_ONLY) |
| 3263 | ref_transaction_add_update(loose_transaction, update->refname, |
| 3264 | update->flags, &update->new_oid, |
| 3265 | &update->old_oid, &update->peeled, |
| 3266 | NULL, NULL, |
| 3267 | update->committer_info, update->msg); |
| 3268 | else |
| 3269 | ref_transaction_add_update(loose_transaction, update->refname, |
| 3270 | update->flags & ~REF_HAVE_OLD, |
| 3271 | update->new_target ? NULL : &update->new_oid, NULL, |
| 3272 | &update->peeled, update->new_target, |
| 3273 | NULL, update->committer_info, |
| 3274 | NULL); |
| 3275 | } else { |
| 3276 | ref_transaction_add_update(packed_transaction, update->refname, |
| 3277 | update->flags & ~REF_HAVE_OLD, |
| 3278 | &update->new_oid, &update->old_oid, |
| 3279 | &update->peeled, NULL, NULL, |
| 3280 | update->committer_info, NULL); |
| 3281 | } |
| 3282 | } |
| 3283 | |
| 3284 | if (packed_refs_lock(refs->packed_ref_store, 0, err)) { |
| 3285 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3286 | goto cleanup; |
| 3287 | } |
| 3288 | |
| 3289 | if (refs_verify_refnames_available(&refs->base, &refnames_to_check, |
| 3290 | &affected_refnames, NULL, transaction, |
| 3291 | 1, err)) { |
| 3292 | packed_refs_unlock(refs->packed_ref_store); |
| 3293 | ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; |
| 3294 | goto cleanup; |
| 3295 | } |
| 3296 | |
| 3297 | if (ref_transaction_commit(packed_transaction, err)) { |
| 3298 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3299 | goto cleanup; |
| 3300 | } |
| 3301 | packed_refs_unlock(refs->packed_ref_store); |
| 3302 | |
| 3303 | if (loose_transaction) { |
| 3304 | if (ref_transaction_prepare(loose_transaction, err) || |
| 3305 | ref_transaction_commit(loose_transaction, err)) { |
| 3306 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3307 | goto cleanup; |
| 3308 | } |
| 3309 | } |
| 3310 | |
| 3311 | cleanup: |
| 3312 | if (loose_transaction) |
| 3313 | ref_transaction_free(loose_transaction); |
| 3314 | if (packed_transaction) |
| 3315 | ref_transaction_free(packed_transaction); |
| 3316 | transaction->state = REF_TRANSACTION_CLOSED; |
| 3317 | string_list_clear(&affected_refnames, 0); |
| 3318 | string_list_clear(&refnames_to_check, 0); |
| 3319 | return ret; |
| 3320 | } |
| 3321 | |
| 3322 | static int files_transaction_finish(struct ref_store *ref_store, |
| 3323 | struct ref_transaction *transaction, |
| 3324 | struct strbuf *err) |
| 3325 | { |
| 3326 | struct files_ref_store *refs = |
| 3327 | files_downcast(ref_store, 0, "ref_transaction_finish"); |
| 3328 | const struct files_ref_store_write_options *write_opts = files_ref_store_write_options(refs); |
| 3329 | size_t i; |
| 3330 | int ret = 0; |
| 3331 | struct strbuf sb = STRBUF_INIT; |
| 3332 | struct files_transaction_backend_data *backend_data; |
| 3333 | struct ref_transaction *packed_transaction; |
| 3334 | |
| 3335 | |
| 3336 | assert(err); |
| 3337 | |
| 3338 | if (transaction->flags & REF_TRANSACTION_FLAG_INITIAL) |
| 3339 | return files_transaction_finish_initial(refs, transaction, err); |
| 3340 | if (!transaction->nr) { |
| 3341 | transaction->state = REF_TRANSACTION_CLOSED; |
| 3342 | return 0; |
| 3343 | } |
| 3344 | |
| 3345 | backend_data = transaction->backend_data; |
| 3346 | packed_transaction = backend_data->packed_transaction; |
| 3347 | |
| 3348 | /* Perform updates first so live commits remain referenced */ |
| 3349 | for (i = 0; i < transaction->nr; i++) { |
| 3350 | struct ref_update *update = transaction->updates[i]; |
| 3351 | struct ref_lock *lock = update->backend_data; |
| 3352 | |
| 3353 | if (update->rejection_err) |
| 3354 | continue; |
| 3355 | |
| 3356 | if (update->flags & REF_NEEDS_COMMIT || |
| 3357 | update->flags & REF_LOG_ONLY) { |
| 3358 | if (parse_and_write_reflog(refs, update, lock, err)) { |
| 3359 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3360 | goto cleanup; |
| 3361 | } |
| 3362 | } |
| 3363 | |
| 3364 | /* |
| 3365 | * We try creating a symlink, if that succeeds we continue to the |
| 3366 | * next update. If not, we try and create a regular symref. |
| 3367 | */ |
| 3368 | if (update->new_target && write_opts->prefer_symlink_refs) |
| 3369 | /* |
| 3370 | * By using the `NOT_CONSTANT()` trick, we can avoid |
| 3371 | * errors by `clang`'s `-Wunreachable` logic that would |
| 3372 | * report that the `continue` statement is not reachable |
| 3373 | * when `NO_SYMLINK_HEAD` is `#define`d. |
| 3374 | */ |
| 3375 | if (NOT_CONSTANT(!create_ref_symlink(lock, update->new_target))) |
| 3376 | continue; |
| 3377 | |
| 3378 | if (update->flags & REF_NEEDS_COMMIT) { |
| 3379 | clear_loose_ref_cache(refs); |
| 3380 | if (commit_ref(lock)) { |
| 3381 | strbuf_addf(err, "couldn't set '%s'", lock->ref_name); |
| 3382 | unlock_ref(lock); |
| 3383 | update->backend_data = NULL; |
| 3384 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3385 | goto cleanup; |
| 3386 | } |
| 3387 | } |
| 3388 | } |
| 3389 | |
| 3390 | /* |
| 3391 | * Now that updates are safely completed, we can perform |
| 3392 | * deletes. First delete the reflogs of any references that |
| 3393 | * will be deleted, since (in the unexpected event of an |
| 3394 | * error) leaving a reference without a reflog is less bad |
| 3395 | * than leaving a reflog without a reference (the latter is a |
| 3396 | * mildly invalid repository state): |
| 3397 | */ |
| 3398 | for (i = 0; i < transaction->nr; i++) { |
| 3399 | struct ref_update *update = transaction->updates[i]; |
| 3400 | |
| 3401 | if (update->rejection_err) |
| 3402 | continue; |
| 3403 | |
| 3404 | if (update->flags & REF_DELETING && |
| 3405 | !(update->flags & REF_LOG_ONLY) && |
| 3406 | !(update->flags & REF_IS_PRUNING)) { |
| 3407 | strbuf_reset(&sb); |
| 3408 | files_reflog_path(refs, &sb, update->refname); |
| 3409 | if (!unlink_or_warn(sb.buf)) |
| 3410 | try_remove_empty_parents(refs, update->refname, |
| 3411 | REMOVE_EMPTY_PARENTS_REFLOG); |
| 3412 | } |
| 3413 | } |
| 3414 | |
| 3415 | /* |
| 3416 | * Perform deletes now that updates are safely completed. |
| 3417 | * |
| 3418 | * First delete any packed versions of the references, while |
| 3419 | * retaining the packed-refs lock: |
| 3420 | */ |
| 3421 | if (packed_transaction) { |
| 3422 | ret = ref_transaction_commit(packed_transaction, err); |
| 3423 | ref_transaction_free(packed_transaction); |
| 3424 | packed_transaction = NULL; |
| 3425 | backend_data->packed_transaction = NULL; |
| 3426 | if (ret) |
| 3427 | goto cleanup; |
| 3428 | } |
| 3429 | |
| 3430 | /* Now delete the loose versions of the references: */ |
| 3431 | for (i = 0; i < transaction->nr; i++) { |
| 3432 | struct ref_update *update = transaction->updates[i]; |
| 3433 | struct ref_lock *lock = update->backend_data; |
| 3434 | |
| 3435 | if (update->rejection_err) |
| 3436 | continue; |
| 3437 | |
| 3438 | if (update->flags & REF_DELETING && |
| 3439 | !(update->flags & REF_LOG_ONLY)) { |
| 3440 | update->flags |= REF_DELETED_RMDIR; |
| 3441 | if (!(update->type & REF_ISPACKED) || |
| 3442 | update->type & REF_ISSYMREF) { |
| 3443 | /* It is a loose reference. */ |
| 3444 | strbuf_reset(&sb); |
| 3445 | files_ref_path(refs, &sb, lock->ref_name); |
| 3446 | if (unlink_or_msg(sb.buf, err)) { |
| 3447 | ret = REF_TRANSACTION_ERROR_GENERIC; |
| 3448 | goto cleanup; |
| 3449 | } |
| 3450 | } |
| 3451 | } |
| 3452 | } |
| 3453 | |
| 3454 | clear_loose_ref_cache(refs); |
| 3455 | |
| 3456 | cleanup: |
| 3457 | files_transaction_cleanup(refs, transaction); |
| 3458 | |
| 3459 | for (i = 0; i < transaction->nr; i++) { |
| 3460 | struct ref_update *update = transaction->updates[i]; |
| 3461 | |
| 3462 | if (update->flags & REF_DELETED_RMDIR) { |
| 3463 | /* |
| 3464 | * The reference was deleted. Delete any |
| 3465 | * empty parent directories. (Note that this |
| 3466 | * can only work because we have already |
| 3467 | * removed the lockfile.) |
| 3468 | */ |
| 3469 | try_remove_empty_parents(refs, update->refname, |
| 3470 | REMOVE_EMPTY_PARENTS_REF); |
| 3471 | } |
| 3472 | } |
| 3473 | |
| 3474 | strbuf_release(&sb); |
| 3475 | return ret; |
| 3476 | } |
| 3477 | |
| 3478 | static int files_transaction_abort(struct ref_store *ref_store, |
| 3479 | struct ref_transaction *transaction, |
| 3480 | struct strbuf *err UNUSED) |
| 3481 | { |
| 3482 | struct files_ref_store *refs = |
| 3483 | files_downcast(ref_store, 0, "ref_transaction_abort"); |
| 3484 | |
| 3485 | files_transaction_cleanup(refs, transaction); |
| 3486 | return 0; |
| 3487 | } |
| 3488 | |
| 3489 | struct expire_reflog_cb { |
| 3490 | reflog_expiry_should_prune_fn *should_prune_fn; |
| 3491 | void *policy_cb; |
| 3492 | FILE *newlog; |
| 3493 | struct object_id last_kept_oid; |
| 3494 | unsigned int rewrite:1, |
| 3495 | dry_run:1; |
| 3496 | }; |
| 3497 | |
| 3498 | static int expire_reflog_ent(const char *refname UNUSED, |
| 3499 | struct object_id *ooid, struct object_id *noid, |
| 3500 | const char *email, timestamp_t timestamp, int tz, |
| 3501 | const char *message, void *cb_data) |
| 3502 | { |
| 3503 | struct expire_reflog_cb *cb = cb_data; |
| 3504 | reflog_expiry_should_prune_fn *fn = cb->should_prune_fn; |
| 3505 | |
| 3506 | if (cb->rewrite) |
| 3507 | ooid = &cb->last_kept_oid; |
| 3508 | |
| 3509 | if (fn(ooid, noid, email, timestamp, tz, message, cb->policy_cb)) |
| 3510 | return 0; |
| 3511 | |
| 3512 | if (cb->dry_run) |
| 3513 | return 0; /* --dry-run */ |
| 3514 | |
| 3515 | fprintf(cb->newlog, "%s %s %s %"PRItime" %+05d\t%s", oid_to_hex(ooid), |
| 3516 | oid_to_hex(noid), email, timestamp, tz, message); |
| 3517 | oidcpy(&cb->last_kept_oid, noid); |
| 3518 | |
| 3519 | return 0; |
| 3520 | } |
| 3521 | |
| 3522 | static int files_reflog_expire(struct ref_store *ref_store, |
| 3523 | const char *refname, |
| 3524 | unsigned int expire_flags, |
| 3525 | reflog_expiry_prepare_fn prepare_fn, |
| 3526 | reflog_expiry_should_prune_fn should_prune_fn, |
| 3527 | reflog_expiry_cleanup_fn cleanup_fn, |
| 3528 | void *policy_cb_data) |
| 3529 | { |
| 3530 | struct files_ref_store *refs = |
| 3531 | files_downcast(ref_store, REF_STORE_WRITE, "reflog_expire"); |
| 3532 | struct lock_file reflog_lock = LOCK_INIT; |
| 3533 | struct expire_reflog_cb cb; |
| 3534 | struct ref_lock *lock; |
| 3535 | struct strbuf log_file_sb = STRBUF_INIT; |
| 3536 | char *log_file; |
| 3537 | int status = 0; |
| 3538 | struct strbuf err = STRBUF_INIT; |
| 3539 | const struct object_id *oid; |
| 3540 | |
| 3541 | memset(&cb, 0, sizeof(cb)); |
| 3542 | cb.rewrite = !!(expire_flags & EXPIRE_REFLOGS_REWRITE); |
| 3543 | cb.dry_run = !!(expire_flags & EXPIRE_REFLOGS_DRY_RUN); |
| 3544 | cb.policy_cb = policy_cb_data; |
| 3545 | cb.should_prune_fn = should_prune_fn; |
| 3546 | |
| 3547 | /* |
| 3548 | * The reflog file is locked by holding the lock on the |
| 3549 | * reference itself, plus we might need to update the |
| 3550 | * reference if --updateref was specified: |
| 3551 | */ |
| 3552 | lock = lock_ref_oid_basic(refs, refname, &err); |
| 3553 | if (!lock) { |
| 3554 | error("cannot lock ref '%s': %s", refname, err.buf); |
| 3555 | strbuf_release(&err); |
| 3556 | return -1; |
| 3557 | } |
| 3558 | oid = &lock->old_oid; |
| 3559 | |
| 3560 | /* |
| 3561 | * When refs are deleted, their reflog is deleted before the |
| 3562 | * ref itself is deleted. This is because there is no separate |
| 3563 | * lock for reflog; instead we take a lock on the ref with |
| 3564 | * lock_ref_oid_basic(). |
| 3565 | * |
| 3566 | * If a race happens and the reflog doesn't exist after we've |
| 3567 | * acquired the lock that's OK. We've got nothing more to do; |
| 3568 | * We were asked to delete the reflog, but someone else |
| 3569 | * deleted it! The caller doesn't care that we deleted it, |
| 3570 | * just that it is deleted. So we can return successfully. |
| 3571 | */ |
| 3572 | if (!refs_reflog_exists(ref_store, refname)) { |
| 3573 | unlock_ref(lock); |
| 3574 | return 0; |
| 3575 | } |
| 3576 | |
| 3577 | files_reflog_path(refs, &log_file_sb, refname); |
| 3578 | log_file = strbuf_detach(&log_file_sb, NULL); |
| 3579 | if (!cb.dry_run) { |
| 3580 | /* |
| 3581 | * Even though holding $GIT_DIR/logs/$reflog.lock has |
| 3582 | * no locking implications, we use the lock_file |
| 3583 | * machinery here anyway because it does a lot of the |
| 3584 | * work we need, including cleaning up if the program |
| 3585 | * exits unexpectedly. |
| 3586 | */ |
| 3587 | if (repo_hold_lock_file_for_update(ref_store->repo, |
| 3588 | &reflog_lock, log_file, |
| 3589 | 0) < 0) { |
| 3590 | struct strbuf err = STRBUF_INIT; |
| 3591 | unable_to_lock_message(log_file, errno, &err); |
| 3592 | error("%s", err.buf); |
| 3593 | strbuf_release(&err); |
| 3594 | goto failure; |
| 3595 | } |
| 3596 | cb.newlog = fdopen_lock_file(&reflog_lock, "w"); |
| 3597 | if (!cb.newlog) { |
| 3598 | error("cannot fdopen %s (%s)", |
| 3599 | get_lock_file_path(&reflog_lock), strerror(errno)); |
| 3600 | goto failure; |
| 3601 | } |
| 3602 | } |
| 3603 | |
| 3604 | (*prepare_fn)(refname, oid, cb.policy_cb); |
| 3605 | refs_for_each_reflog_ent(ref_store, refname, expire_reflog_ent, &cb); |
| 3606 | (*cleanup_fn)(cb.policy_cb); |
| 3607 | |
| 3608 | if (!cb.dry_run) { |
| 3609 | /* |
| 3610 | * It doesn't make sense to adjust a reference pointed |
| 3611 | * to by a symbolic ref based on expiring entries in |
| 3612 | * the symbolic reference's reflog. Nor can we update |
| 3613 | * a reference if there are no remaining reflog |
| 3614 | * entries. |
| 3615 | */ |
| 3616 | int update = 0; |
| 3617 | |
| 3618 | if ((expire_flags & EXPIRE_REFLOGS_UPDATE_REF) && |
| 3619 | !is_null_oid(&cb.last_kept_oid)) { |
| 3620 | int type; |
| 3621 | const char *ref; |
| 3622 | |
| 3623 | ref = refs_resolve_ref_unsafe(&refs->base, refname, |
| 3624 | RESOLVE_REF_NO_RECURSE, |
| 3625 | NULL, &type); |
| 3626 | update = !!(ref && !(type & REF_ISSYMREF)); |
| 3627 | } |
| 3628 | |
| 3629 | if (close_lock_file_gently(&reflog_lock)) { |
| 3630 | status |= error("couldn't write %s: %s", log_file, |
| 3631 | strerror(errno)); |
| 3632 | rollback_lock_file(&reflog_lock); |
| 3633 | } else if (update && |
| 3634 | (write_in_full(get_lock_file_fd(&lock->lk), |
| 3635 | oid_to_hex(&cb.last_kept_oid), refs->base.repo->hash_algo->hexsz) < 0 || |
| 3636 | write_str_in_full(get_lock_file_fd(&lock->lk), "\n") < 0 || |
| 3637 | close_ref_gently(lock) < 0)) { |
| 3638 | status |= error("couldn't write %s", |
| 3639 | get_lock_file_path(&lock->lk)); |
| 3640 | rollback_lock_file(&reflog_lock); |
| 3641 | } else if (commit_lock_file(&reflog_lock)) { |
| 3642 | status |= error("unable to write reflog '%s' (%s)", |
| 3643 | log_file, strerror(errno)); |
| 3644 | } else if (update && commit_ref(lock)) { |
| 3645 | status |= error("couldn't set %s", lock->ref_name); |
| 3646 | } |
| 3647 | } |
| 3648 | free(log_file); |
| 3649 | unlock_ref(lock); |
| 3650 | return status; |
| 3651 | |
| 3652 | failure: |
| 3653 | rollback_lock_file(&reflog_lock); |
| 3654 | free(log_file); |
| 3655 | unlock_ref(lock); |
| 3656 | return -1; |
| 3657 | } |
| 3658 | |
| 3659 | static int files_ref_store_create_on_disk(struct ref_store *ref_store, |
| 3660 | int flags, |
| 3661 | struct strbuf *err UNUSED) |
| 3662 | { |
| 3663 | struct files_ref_store *refs = |
| 3664 | files_downcast(ref_store, REF_STORE_WRITE, "create"); |
| 3665 | struct strbuf sb = STRBUF_INIT; |
| 3666 | |
| 3667 | /* |
| 3668 | * We need to create a "refs" dir in any case so that older versions of |
| 3669 | * Git can tell that this is a repository. This serves two main purposes: |
| 3670 | * |
| 3671 | * - Clients will know to stop walking the parent-directory chain when |
| 3672 | * detecting the Git repository. Otherwise they may end up detecting |
| 3673 | * a Git repository in a parent directory instead. |
| 3674 | * |
| 3675 | * - Instead of failing to detect a repository with unknown reference |
| 3676 | * format altogether, old clients will print an error saying that |
| 3677 | * they do not understand the reference format extension. |
| 3678 | */ |
| 3679 | strbuf_addf(&sb, "%s/refs", ref_store->gitdir); |
| 3680 | safe_create_dir(refs->base.repo, sb.buf, 1); |
| 3681 | adjust_shared_perm(refs->base.repo, sb.buf); |
| 3682 | |
| 3683 | /* |
| 3684 | * There is no need to create directories for common refs when creating |
| 3685 | * a worktree ref store. |
| 3686 | */ |
| 3687 | if (!(flags & REF_STORE_CREATE_ON_DISK_IS_WORKTREE)) { |
| 3688 | /* |
| 3689 | * Create .git/refs/{heads,tags} |
| 3690 | */ |
| 3691 | strbuf_reset(&sb); |
| 3692 | files_ref_path(refs, &sb, "refs/heads"); |
| 3693 | safe_create_dir(refs->base.repo, sb.buf, 1); |
| 3694 | |
| 3695 | strbuf_reset(&sb); |
| 3696 | files_ref_path(refs, &sb, "refs/tags"); |
| 3697 | safe_create_dir(refs->base.repo, sb.buf, 1); |
| 3698 | } |
| 3699 | |
| 3700 | strbuf_release(&sb); |
| 3701 | return 0; |
| 3702 | } |
| 3703 | |
| 3704 | struct remove_one_root_ref_data { |
| 3705 | const char *gitdir; |
| 3706 | struct strbuf *err; |
| 3707 | }; |
| 3708 | |
| 3709 | static int remove_one_root_ref(const char *refname, |
| 3710 | void *cb_data) |
| 3711 | { |
| 3712 | struct remove_one_root_ref_data *data = cb_data; |
| 3713 | struct strbuf buf = STRBUF_INIT; |
| 3714 | int ret = 0; |
| 3715 | |
| 3716 | strbuf_addf(&buf, "%s/%s", data->gitdir, refname); |
| 3717 | |
| 3718 | ret = unlink(buf.buf); |
| 3719 | if (ret < 0) |
| 3720 | strbuf_addf(data->err, "could not delete %s: %s\n", |
| 3721 | refname, strerror(errno)); |
| 3722 | |
| 3723 | strbuf_release(&buf); |
| 3724 | return ret; |
| 3725 | } |
| 3726 | |
| 3727 | static int files_ref_store_remove_on_disk(struct ref_store *ref_store, |
| 3728 | struct strbuf *err) |
| 3729 | { |
| 3730 | struct files_ref_store *refs = |
| 3731 | files_downcast(ref_store, REF_STORE_WRITE, "remove"); |
| 3732 | struct remove_one_root_ref_data data = { |
| 3733 | .gitdir = refs->base.gitdir, |
| 3734 | .err = err, |
| 3735 | }; |
| 3736 | struct strbuf sb = STRBUF_INIT; |
| 3737 | int ret = 0; |
| 3738 | |
| 3739 | strbuf_addf(&sb, "%s/refs", refs->base.gitdir); |
| 3740 | if (remove_dir_recursively(&sb, 0) < 0) { |
| 3741 | strbuf_addf(err, "could not delete refs: %s", |
| 3742 | strerror(errno)); |
| 3743 | ret = -1; |
| 3744 | } |
| 3745 | strbuf_reset(&sb); |
| 3746 | |
| 3747 | strbuf_addf(&sb, "%s/logs", refs->base.gitdir); |
| 3748 | if (remove_dir_recursively(&sb, 0) < 0) { |
| 3749 | strbuf_addf(err, "could not delete logs: %s", |
| 3750 | strerror(errno)); |
| 3751 | ret = -1; |
| 3752 | } |
| 3753 | strbuf_reset(&sb); |
| 3754 | |
| 3755 | if (for_each_root_ref(refs, remove_one_root_ref, &data) < 0) |
| 3756 | ret = -1; |
| 3757 | |
| 3758 | /* |
| 3759 | * Directly access the cleanup functions for packed-refs as the generic function |
| 3760 | * would try to clear stubs which isn't required for the files backend. |
| 3761 | */ |
| 3762 | if (refs->packed_ref_store->be->remove_on_disk(refs->packed_ref_store, err) < 0) |
| 3763 | ret = -1; |
| 3764 | |
| 3765 | strbuf_release(&sb); |
| 3766 | return ret; |
| 3767 | } |
| 3768 | |
| 3769 | /* |
| 3770 | * For refs and reflogs, they share a unified interface when scanning |
| 3771 | * the whole directory. This function is used as the callback for each |
| 3772 | * regular file or symlink in the directory. |
| 3773 | */ |
| 3774 | typedef int (*files_fsck_refs_fn)(struct ref_store *ref_store, |
| 3775 | struct fsck_options *o, |
| 3776 | const char *refname, |
| 3777 | const char *path, |
| 3778 | int mode); |
| 3779 | |
| 3780 | static int files_fsck_symref_target(struct ref_store *ref_store, |
| 3781 | struct fsck_options *o, |
| 3782 | struct fsck_ref_report *report, |
| 3783 | const char *refname, |
| 3784 | struct strbuf *referent, |
| 3785 | unsigned int symbolic_link) |
| 3786 | { |
| 3787 | char orig_last_byte; |
| 3788 | size_t orig_len; |
| 3789 | int ret = 0; |
| 3790 | |
| 3791 | orig_len = referent->len; |
| 3792 | orig_last_byte = referent->buf[orig_len - 1]; |
| 3793 | |
| 3794 | if (!symbolic_link) { |
| 3795 | strbuf_rtrim(referent); |
| 3796 | |
| 3797 | if (referent->len == orig_len || |
| 3798 | (referent->len < orig_len && orig_last_byte != '\n')) { |
| 3799 | ret |= fsck_report_ref(o, report, |
| 3800 | FSCK_MSG_REF_MISSING_NEWLINE, |
| 3801 | "misses LF at the end"); |
| 3802 | } |
| 3803 | |
| 3804 | if (referent->len != orig_len && referent->len != orig_len - 1) { |
| 3805 | ret |= fsck_report_ref(o, report, |
| 3806 | FSCK_MSG_TRAILING_REF_CONTENT, |
| 3807 | "has trailing whitespaces or newlines"); |
| 3808 | } |
| 3809 | } |
| 3810 | |
| 3811 | ret |= refs_fsck_symref(ref_store, o, report, refname, referent->buf); |
| 3812 | |
| 3813 | return ret ? -1 : 0; |
| 3814 | } |
| 3815 | |
| 3816 | static int files_fsck_refs_content(struct ref_store *ref_store, |
| 3817 | struct fsck_options *o, |
| 3818 | const char *target_name, |
| 3819 | const char *path, |
| 3820 | int mode) |
| 3821 | { |
| 3822 | struct strbuf ref_content = STRBUF_INIT; |
| 3823 | struct strbuf abs_gitdir = STRBUF_INIT; |
| 3824 | struct strbuf referent = STRBUF_INIT; |
| 3825 | struct fsck_ref_report report = { 0 }; |
| 3826 | const char *trailing = NULL; |
| 3827 | unsigned int type = 0; |
| 3828 | int failure_errno = 0; |
| 3829 | struct object_id oid; |
| 3830 | int ret = 0; |
| 3831 | |
| 3832 | report.path = target_name; |
| 3833 | |
| 3834 | if (S_ISLNK(mode)) { |
| 3835 | const char *relative_referent_path = NULL; |
| 3836 | |
| 3837 | ret = fsck_report_ref(o, &report, |
| 3838 | FSCK_MSG_SYMLINK_REF, |
| 3839 | "use deprecated symbolic link for symref"); |
| 3840 | |
| 3841 | strbuf_add_absolute_path(&abs_gitdir, ref_store->repo->gitdir); |
| 3842 | strbuf_normalize_path(&abs_gitdir); |
| 3843 | if (!is_dir_sep(abs_gitdir.buf[abs_gitdir.len - 1])) |
| 3844 | strbuf_addch(&abs_gitdir, '/'); |
| 3845 | |
| 3846 | strbuf_add_real_path(&ref_content, path); |
| 3847 | skip_prefix(ref_content.buf, abs_gitdir.buf, |
| 3848 | &relative_referent_path); |
| 3849 | |
| 3850 | if (relative_referent_path) |
| 3851 | strbuf_addstr(&referent, relative_referent_path); |
| 3852 | else |
| 3853 | strbuf_addbuf(&referent, &ref_content); |
| 3854 | |
| 3855 | ret |= files_fsck_symref_target(ref_store, o, &report, |
| 3856 | target_name, &referent, 1); |
| 3857 | goto cleanup; |
| 3858 | } |
| 3859 | |
| 3860 | if (strbuf_read_file(&ref_content, path, 0) < 0) { |
| 3861 | /* |
| 3862 | * Ref file could be removed by another concurrent process. We should |
| 3863 | * ignore this error and continue to the next ref. |
| 3864 | */ |
| 3865 | if (errno == ENOENT) |
| 3866 | goto cleanup; |
| 3867 | |
| 3868 | ret = error_errno(_("cannot read ref file '%s'"), path); |
| 3869 | goto cleanup; |
| 3870 | } |
| 3871 | |
| 3872 | if (parse_loose_ref_contents(ref_store->repo->hash_algo, |
| 3873 | ref_content.buf, &oid, &referent, |
| 3874 | &type, &trailing, &failure_errno)) { |
| 3875 | strbuf_rtrim(&ref_content); |
| 3876 | ret = fsck_report_ref(o, &report, |
| 3877 | FSCK_MSG_BAD_REF_CONTENT, |
| 3878 | "%s", ref_content.buf); |
| 3879 | goto cleanup; |
| 3880 | } |
| 3881 | |
| 3882 | if (!(type & REF_ISSYMREF)) { |
| 3883 | if (!*trailing) { |
| 3884 | ret = fsck_report_ref(o, &report, |
| 3885 | FSCK_MSG_REF_MISSING_NEWLINE, |
| 3886 | "misses LF at the end"); |
| 3887 | goto cleanup; |
| 3888 | } |
| 3889 | if (*trailing != '\n' || *(trailing + 1)) { |
| 3890 | ret = fsck_report_ref(o, &report, |
| 3891 | FSCK_MSG_TRAILING_REF_CONTENT, |
| 3892 | "has trailing garbage: '%s'", trailing); |
| 3893 | goto cleanup; |
| 3894 | } |
| 3895 | |
| 3896 | ret = refs_fsck_ref(ref_store, o, &report, target_name, &oid); |
| 3897 | } else { |
| 3898 | ret = files_fsck_symref_target(ref_store, o, &report, |
| 3899 | target_name, &referent, 0); |
| 3900 | goto cleanup; |
| 3901 | } |
| 3902 | |
| 3903 | cleanup: |
| 3904 | strbuf_release(&ref_content); |
| 3905 | strbuf_release(&referent); |
| 3906 | strbuf_release(&abs_gitdir); |
| 3907 | return ret; |
| 3908 | } |
| 3909 | |
| 3910 | static int files_fsck_refs_name(struct ref_store *ref_store UNUSED, |
| 3911 | struct fsck_options *o, |
| 3912 | const char *refname, |
| 3913 | const char *path UNUSED, |
| 3914 | int mode UNUSED) |
| 3915 | { |
| 3916 | struct strbuf sb = STRBUF_INIT; |
| 3917 | int ret = 0; |
| 3918 | |
| 3919 | if (is_root_ref(refname)) |
| 3920 | goto cleanup; |
| 3921 | |
| 3922 | if (check_refname_format(refname, 0)) { |
| 3923 | struct fsck_ref_report report = { 0 }; |
| 3924 | |
| 3925 | report.path = refname; |
| 3926 | ret = fsck_report_ref(o, &report, |
| 3927 | FSCK_MSG_BAD_REF_NAME, |
| 3928 | "invalid refname format"); |
| 3929 | } |
| 3930 | |
| 3931 | cleanup: |
| 3932 | strbuf_release(&sb); |
| 3933 | return ret; |
| 3934 | } |
| 3935 | |
| 3936 | static const files_fsck_refs_fn fsck_refs_fn[]= { |
| 3937 | files_fsck_refs_name, |
| 3938 | files_fsck_refs_content, |
| 3939 | NULL, |
| 3940 | }; |
| 3941 | |
| 3942 | static int files_fsck_ref(struct ref_store *ref_store, |
| 3943 | struct fsck_options *o, |
| 3944 | const char *refname, |
| 3945 | const char *path, |
| 3946 | int mode) |
| 3947 | { |
| 3948 | int ret = 0; |
| 3949 | |
| 3950 | if (o->verbose) |
| 3951 | fprintf_ln(stderr, "Checking %s", refname); |
| 3952 | |
| 3953 | if (!S_ISREG(mode) && !S_ISLNK(mode)) { |
| 3954 | struct fsck_ref_report report = { .path = refname }; |
| 3955 | |
| 3956 | if (fsck_report_ref(o, &report, |
| 3957 | FSCK_MSG_BAD_REF_FILETYPE, |
| 3958 | "unexpected file type")) |
| 3959 | ret = -1; |
| 3960 | goto out; |
| 3961 | } |
| 3962 | |
| 3963 | for (size_t i = 0; fsck_refs_fn[i]; i++) |
| 3964 | if (fsck_refs_fn[i](ref_store, o, refname, path, mode)) |
| 3965 | ret = -1; |
| 3966 | |
| 3967 | out: |
| 3968 | return ret; |
| 3969 | } |
| 3970 | |
| 3971 | static int files_fsck_refs_dir(struct ref_store *ref_store, |
| 3972 | struct fsck_options *o, |
| 3973 | struct worktree *wt) |
| 3974 | { |
| 3975 | struct strbuf refname = STRBUF_INIT; |
| 3976 | struct strbuf sb = STRBUF_INIT; |
| 3977 | struct dir_iterator *iter; |
| 3978 | const char *filename; |
| 3979 | int iter_status; |
| 3980 | int ret = 0; |
| 3981 | |
| 3982 | strbuf_addf(&sb, "%s/refs", ref_store->gitdir); |
| 3983 | |
| 3984 | iter = dir_iterator_begin(sb.buf, 0); |
| 3985 | if (!iter) { |
| 3986 | if (errno == ENOENT && !is_main_worktree(wt)) |
| 3987 | goto out; |
| 3988 | |
| 3989 | ret = error_errno(_("cannot open directory %s"), sb.buf); |
| 3990 | goto out; |
| 3991 | } |
| 3992 | |
| 3993 | while ((iter_status = dir_iterator_advance(iter)) == ITER_OK) { |
| 3994 | if (S_ISDIR(iter->st.st_mode)) |
| 3995 | continue; |
| 3996 | |
| 3997 | strbuf_reset(&refname); |
| 3998 | if (!is_main_worktree(wt)) |
| 3999 | strbuf_addf(&refname, "worktrees/%s/", wt->id); |
| 4000 | strbuf_addf(&refname, "refs/%s", iter->relative_path); |
| 4001 | |
| 4002 | filename = basename((char *) iter->path.buf); |
| 4003 | |
| 4004 | /* |
| 4005 | * Ignore the files ending with ".lock" as they may be lock files. |
| 4006 | * However, do not skip invalid refnames with '.lock' suffix. |
| 4007 | */ |
| 4008 | if (filename[0] != '.' && ends_with(filename, ".lock")) |
| 4009 | continue; |
| 4010 | |
| 4011 | if (files_fsck_ref(ref_store, o, refname.buf, |
| 4012 | iter->path.buf, iter->st.st_mode) < 0) |
| 4013 | ret = -1; |
| 4014 | } |
| 4015 | |
| 4016 | if (iter_status != ITER_DONE) |
| 4017 | ret = error(_("failed to iterate over '%s'"), sb.buf); |
| 4018 | |
| 4019 | out: |
| 4020 | dir_iterator_free(iter); |
| 4021 | strbuf_release(&sb); |
| 4022 | strbuf_release(&refname); |
| 4023 | return ret; |
| 4024 | } |
| 4025 | |
| 4026 | struct files_fsck_root_ref_data { |
| 4027 | struct files_ref_store *refs; |
| 4028 | struct fsck_options *o; |
| 4029 | struct worktree *wt; |
| 4030 | struct strbuf refname; |
| 4031 | struct strbuf path; |
| 4032 | }; |
| 4033 | |
| 4034 | static int files_fsck_root_ref(const char *refname, void *cb_data) |
| 4035 | { |
| 4036 | struct files_fsck_root_ref_data *data = cb_data; |
| 4037 | struct stat st; |
| 4038 | |
| 4039 | strbuf_reset(&data->refname); |
| 4040 | if (!is_main_worktree(data->wt)) |
| 4041 | strbuf_addf(&data->refname, "worktrees/%s/", data->wt->id); |
| 4042 | strbuf_addstr(&data->refname, refname); |
| 4043 | |
| 4044 | strbuf_reset(&data->path); |
| 4045 | strbuf_addf(&data->path, "%s/%s", data->refs->gitcommondir, data->refname.buf); |
| 4046 | |
| 4047 | if (stat(data->path.buf, &st)) { |
| 4048 | if (errno == ENOENT) |
| 4049 | return 0; |
| 4050 | return error_errno("failed to read ref: '%s'", data->path.buf); |
| 4051 | } |
| 4052 | |
| 4053 | return files_fsck_ref(&data->refs->base, data->o, data->refname.buf, |
| 4054 | data->path.buf, st.st_mode); |
| 4055 | } |
| 4056 | |
| 4057 | static int files_fsck(struct ref_store *ref_store, |
| 4058 | struct fsck_options *o, |
| 4059 | struct worktree *wt) |
| 4060 | { |
| 4061 | struct files_ref_store *refs = |
| 4062 | files_downcast(ref_store, REF_STORE_READ, "fsck"); |
| 4063 | struct files_fsck_root_ref_data data = { |
| 4064 | .refs = refs, |
| 4065 | .o = o, |
| 4066 | .wt = wt, |
| 4067 | .refname = STRBUF_INIT, |
| 4068 | .path = STRBUF_INIT, |
| 4069 | }; |
| 4070 | int ret = 0; |
| 4071 | |
| 4072 | if (files_fsck_refs_dir(ref_store, o, wt) < 0) |
| 4073 | ret = -1; |
| 4074 | |
| 4075 | if (for_each_root_ref(refs, files_fsck_root_ref, &data) < 0) |
| 4076 | ret = -1; |
| 4077 | |
| 4078 | if (refs->packed_ref_store->be->fsck(refs->packed_ref_store, o, wt) < 0) |
| 4079 | ret = -1; |
| 4080 | |
| 4081 | strbuf_release(&data.refname); |
| 4082 | strbuf_release(&data.path); |
| 4083 | return ret; |
| 4084 | } |
| 4085 | |
| 4086 | struct ref_storage_be refs_be_files = { |
| 4087 | .name = "files", |
| 4088 | .init = files_ref_store_init, |
| 4089 | .release = files_ref_store_release, |
| 4090 | .create_on_disk = files_ref_store_create_on_disk, |
| 4091 | .remove_on_disk = files_ref_store_remove_on_disk, |
| 4092 | |
| 4093 | .transaction_prepare = files_transaction_prepare, |
| 4094 | .transaction_finish = files_transaction_finish, |
| 4095 | .transaction_abort = files_transaction_abort, |
| 4096 | |
| 4097 | .optimize = files_optimize, |
| 4098 | .optimize_required = files_optimize_required, |
| 4099 | .rename_ref = files_rename_ref, |
| 4100 | .copy_ref = files_copy_ref, |
| 4101 | |
| 4102 | .iterator_begin = files_ref_iterator_begin, |
| 4103 | .read_raw_ref = files_read_raw_ref, |
| 4104 | .read_symbolic_ref = files_read_symbolic_ref, |
| 4105 | |
| 4106 | .reflog_iterator_begin = files_reflog_iterator_begin, |
| 4107 | .for_each_reflog_ent = files_for_each_reflog_ent, |
| 4108 | .for_each_reflog_ent_reverse = files_for_each_reflog_ent_reverse, |
| 4109 | .reflog_exists = files_reflog_exists, |
| 4110 | .create_reflog = files_create_reflog, |
| 4111 | .delete_reflog = files_delete_reflog, |
| 4112 | .reflog_expire = files_reflog_expire, |
| 4113 | |
| 4114 | .fsck = files_fsck, |
| 4115 | }; |