entry.c

   1 #include "cache.h"
   2 #include "blob.h"
   3 #include "object-store.h"
   4 #include "dir.h"
   5 #include "streaming.h"
   6 #include "submodule.h"
   7 #include "progress.h"
   8 #include "fsmonitor.h"
   9 #include "entry.h"
  10
  11 static void create_directories(const char *path, int path_len,
  12                                const struct checkout *state)
  13 {
  14         char *buf = xmallocz(path_len);
  15         int len = 0;
  16
  17         while (len < path_len) {
  18                 do {
  19                         buf[len] = path[len];
  20                         len++;
  21                 } while (len < path_len && path[len] != '/');
  22                 if (len >= path_len)
  23                         break;
  24                 buf[len] = 0;
  25
  26                 /*
  27                  * For 'checkout-index --prefix=<dir>', <dir> is
  28                  * allowed to be a symlink to an existing directory,
  29                  * and we set 'state->base_dir_len' below, such that
  30                  * we test the path components of the prefix with the
  31                  * stat() function instead of the lstat() function.
  32                  */
  33                 if (has_dirs_only_path(buf, len, state->base_dir_len))
  34                         continue; /* ok, it is already a directory. */
  35
  36                 /*
  37                  * If this mkdir() would fail, it could be that there
  38                  * is already a symlink or something else exists
  39                  * there, therefore we then try to unlink it and try
  40                  * one more time to create the directory.
  41                  */
  42                 if (mkdir(buf, 0777)) {
  43                         if (errno == EEXIST && state->force &&
  44                             !unlink_or_warn(buf) && !mkdir(buf, 0777))
  45                                 continue;
  46                         die_errno("cannot create directory at '%s'", buf);
  47                 }
  48         }
  49         free(buf);
  50 }
  51
  52 static void remove_subtree(struct strbuf *path)
  53 {
  54         DIR *dir = opendir(path->buf);
  55         struct dirent *de;
  56         int origlen = path->len;
  57
  58         if (!dir)
  59                 die_errno("cannot opendir '%s'", path->buf);
  60         while ((de = readdir(dir)) != NULL) {
  61                 struct stat st;
  62
  63                 if (is_dot_or_dotdot(de->d_name))
  64                         continue;
  65
  66                 strbuf_addch(path, '/');
  67                 strbuf_addstr(path, de->d_name);
  68                 if (lstat(path->buf, &st))
  69                         die_errno("cannot lstat '%s'", path->buf);
  70                 if (S_ISDIR(st.st_mode))
  71                         remove_subtree(path);
  72                 else if (unlink(path->buf))
  73                         die_errno("cannot unlink '%s'", path->buf);
  74                 strbuf_setlen(path, origlen);
  75         }
  76         closedir(dir);
  77         if (rmdir(path->buf))
  78                 die_errno("cannot rmdir '%s'", path->buf);
  79 }
  80
  81 static int create_file(const char *path, unsigned int mode)
  82 {
  83         mode = (mode & 0100) ? 0777 : 0666;
  84         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
  85 }
  86
  87 void *read_blob_entry(const struct cache_entry *ce, unsigned long *size)
  88 {
  89         enum object_type type;
  90         void *blob_data = read_object_file(&ce->oid, &type, size);
  91
  92         if (blob_data) {
  93                 if (type == OBJ_BLOB)
  94                         return blob_data;
  95                 free(blob_data);
  96         }
  97         return NULL;
  98 }
  99
 100 static int open_output_fd(char *path, const struct cache_entry *ce, int to_tempfile)
 101 {
 102         int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
 103         if (to_tempfile) {
 104                 xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
 105                           symlink ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
 106                 return mkstemp(path);
 107         } else {
 108                 return create_file(path, !symlink ? ce->ce_mode : 0666);
 109         }
 110 }
 111
 112 int fstat_checkout_output(int fd, const struct checkout *state, struct stat *st)
 113 {
 114         /* use fstat() only when path == ce->name */
 115         if (fstat_is_reliable() &&
 116             state->refresh_cache && !state->base_dir_len) {
 117                 return !fstat(fd, st);
 118         }
 119         return 0;
 120 }
 121
 122 static int streaming_write_entry(const struct cache_entry *ce, char *path,
 123                                  struct stream_filter *filter,
 124                                  const struct checkout *state, int to_tempfile,
 125                                  int *fstat_done, struct stat *statbuf)
 126 {
 127         int result = 0;
 128         int fd;
 129
 130         fd = open_output_fd(path, ce, to_tempfile);
 131         if (fd < 0)
 132                 return -1;
 133
 134         result |= stream_blob_to_fd(fd, &ce->oid, filter, 1);
 135         *fstat_done = fstat_checkout_output(fd, state, statbuf);
 136         result |= close(fd);
 137
 138         if (result)
 139                 unlink(path);
 140         return result;
 141 }
 142
 143 void enable_delayed_checkout(struct checkout *state)
 144 {
 145         if (!state->delayed_checkout) {
 146                 state->delayed_checkout = xmalloc(sizeof(*state->delayed_checkout));
 147                 state->delayed_checkout->state = CE_CAN_DELAY;
 148                 string_list_init(&state->delayed_checkout->filters, 0);
 149                 string_list_init(&state->delayed_checkout->paths, 0);
 150         }
 151 }
 152
 153 static int remove_available_paths(struct string_list_item *item, void *cb_data)
 154 {
 155         struct string_list *available_paths = cb_data;
 156         struct string_list_item *available;
 157
 158         available = string_list_lookup(available_paths, item->string);
 159         if (available)
 160                 available->util = (void *)item->string;
 161         return !available;
 162 }
 163
 164 int finish_delayed_checkout(struct checkout *state, int *nr_checkouts)
 165 {
 166         int errs = 0;
 167         unsigned delayed_object_count;
 168         off_t filtered_bytes = 0;
 169         struct string_list_item *filter, *path;
 170         struct progress *progress;
 171         struct delayed_checkout *dco = state->delayed_checkout;
 172
 173         if (!state->delayed_checkout)
 174                 return errs;
 175
 176         dco->state = CE_RETRY;
 177         delayed_object_count = dco->paths.nr;
 178         progress = start_delayed_progress(_("Filtering content"), delayed_object_count);
 179         while (dco->filters.nr > 0) {
 180                 for_each_string_list_item(filter, &dco->filters) {
 181                         struct string_list available_paths = STRING_LIST_INIT_NODUP;
 182                         display_progress(progress, delayed_object_count - dco->paths.nr);
 183
 184                         if (!async_query_available_blobs(filter->string, &available_paths)) {
 185                                 /* Filter reported an error */
 186                                 errs = 1;
 187                                 filter->string = "";
 188                                 continue;
 189                         }
 190                         if (available_paths.nr <= 0) {
 191                                 /*
 192                                  * Filter responded with no entries. That means
 193                                  * the filter is done and we can remove the
 194                                  * filter from the list (see
 195                                  * "string_list_remove_empty_items" call below).
 196                                  */
 197                                 filter->string = "";
 198                                 continue;
 199                         }
 200
 201                         /*
 202                          * In dco->paths we store a list of all delayed paths.
 203                          * The filter just send us a list of available paths.
 204                          * Remove them from the list.
 205                          */
 206                         filter_string_list(&dco->paths, 0,
 207                                 &remove_available_paths, &available_paths);
 208
 209                         for_each_string_list_item(path, &available_paths) {
 210                                 struct cache_entry* ce;
 211
 212                                 if (!path->util) {
 213                                         error("external filter '%s' signaled that '%s' "
 214                                               "is now available although it has not been "
 215                                               "delayed earlier",
 216                                               filter->string, path->string);
 217                                         errs |= 1;
 218
 219                                         /*
 220                                          * Do not ask the filter for available blobs,
 221                                          * again, as the filter is likely buggy.
 222                                          */
 223                                         filter->string = "";
 224                                         continue;
 225                                 }
 226                                 ce = index_file_exists(state->istate, path->string,
 227                                                        strlen(path->string), 0);
 228                                 if (ce) {
 229                                         errs |= checkout_entry(ce, state, NULL, nr_checkouts);
 230                                         filtered_bytes += ce->ce_stat_data.sd_size;
 231                                         display_throughput(progress, filtered_bytes);
 232                                 } else
 233                                         errs = 1;
 234                         }
 235                 }
 236                 string_list_remove_empty_items(&dco->filters, 0);
 237         }
 238         stop_progress(&progress);
 239         string_list_clear(&dco->filters, 0);
 240
 241         /* At this point we should not have any delayed paths anymore. */
 242         errs |= dco->paths.nr;
 243         for_each_string_list_item(path, &dco->paths) {
 244                 error("'%s' was not filtered properly", path->string);
 245         }
 246         string_list_clear(&dco->paths, 0);
 247
 248         free(dco);
 249         state->delayed_checkout = NULL;
 250
 251         return errs;
 252 }
 253
 254 void update_ce_after_write(const struct checkout *state, struct cache_entry *ce,
 255                            struct stat *st)
 256 {
 257         if (state->refresh_cache) {
 258                 assert(state->istate);
 259                 fill_stat_cache_info(state->istate, ce, st);
 260                 ce->ce_flags |= CE_UPDATE_IN_BASE;
 261                 mark_fsmonitor_invalid(state->istate, ce);
 262                 state->istate->cache_changed |= CE_ENTRY_CHANGED;
 263         }
 264 }
 265
 266 /* Note: ca is used (and required) iff the entry refers to a regular file. */
 267 static int write_entry(struct cache_entry *ce, char *path, struct conv_attrs *ca,
 268                        const struct checkout *state, int to_tempfile)
 269 {
 270         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
 271         struct delayed_checkout *dco = state->delayed_checkout;
 272         int fd, ret, fstat_done = 0;
 273         char *new_blob;
 274         struct strbuf buf = STRBUF_INIT;
 275         unsigned long size;
 276         ssize_t wrote;
 277         size_t newsize = 0;
 278         struct stat st;
 279         const struct submodule *sub;
 280         struct checkout_metadata meta;
 281
 282         clone_checkout_metadata(&meta, &state->meta, &ce->oid);
 283
 284         if (ce_mode_s_ifmt == S_IFREG) {
 285                 struct stream_filter *filter = get_stream_filter_ca(ca, &ce->oid);
 286                 if (filter &&
 287                     !streaming_write_entry(ce, path, filter,
 288                                            state, to_tempfile,
 289                                            &fstat_done, &st))
 290                         goto finish;
 291         }
 292
 293         switch (ce_mode_s_ifmt) {
 294         case S_IFLNK:
 295                 new_blob = read_blob_entry(ce, &size);
 296                 if (!new_blob)
 297                         return error("unable to read sha1 file of %s (%s)",
 298                                      ce->name, oid_to_hex(&ce->oid));
 299
 300                 /*
 301                  * We can't make a real symlink; write out a regular file entry
 302                  * with the symlink destination as its contents.
 303                  */
 304                 if (!has_symlinks || to_tempfile)
 305                         goto write_file_entry;
 306
 307                 ret = symlink(new_blob, path);
 308                 free(new_blob);
 309                 if (ret)
 310                         return error_errno("unable to create symlink %s", path);
 311                 break;
 312
 313         case S_IFREG:
 314                 /*
 315                  * We do not send the blob in case of a retry, so do not
 316                  * bother reading it at all.
 317                  */
 318                 if (dco && dco->state == CE_RETRY) {
 319                         new_blob = NULL;
 320                         size = 0;
 321                 } else {
 322                         new_blob = read_blob_entry(ce, &size);
 323                         if (!new_blob)
 324                                 return error("unable to read sha1 file of %s (%s)",
 325                                              ce->name, oid_to_hex(&ce->oid));
 326                 }
 327
 328                 /*
 329                  * Convert from git internal format to working tree format
 330                  */
 331                 if (dco && dco->state != CE_NO_DELAY) {
 332                         ret = async_convert_to_working_tree_ca(ca, ce->name,
 333                                                                new_blob, size,
 334                                                                &buf, &meta, dco);
 335                         if (ret && string_list_has_string(&dco->paths, ce->name)) {
 336                                 free(new_blob);
 337                                 goto delayed;
 338                         }
 339                 } else {
 340                         ret = convert_to_working_tree_ca(ca, ce->name, new_blob,
 341                                                          size, &buf, &meta);
 342                 }
 343
 344                 if (ret) {
 345                         free(new_blob);
 346                         new_blob = strbuf_detach(&buf, &newsize);
 347                         size = newsize;
 348                 }
 349                 /*
 350                  * No "else" here as errors from convert are OK at this
 351                  * point. If the error would have been fatal (e.g.
 352                  * filter is required), then we would have died already.
 353                  */
 354
 355         write_file_entry:
 356                 fd = open_output_fd(path, ce, to_tempfile);
 357                 if (fd < 0) {
 358                         free(new_blob);
 359                         return error_errno("unable to create file %s", path);
 360                 }
 361
 362                 wrote = write_in_full(fd, new_blob, size);
 363                 if (!to_tempfile)
 364                         fstat_done = fstat_checkout_output(fd, state, &st);
 365                 close(fd);
 366                 free(new_blob);
 367                 if (wrote < 0)
 368                         return error("unable to write file %s", path);
 369                 break;
 370
 371         case S_IFGITLINK:
 372                 if (to_tempfile)
 373                         return error("cannot create temporary submodule %s", ce->name);
 374                 if (mkdir(path, 0777) < 0)
 375                         return error("cannot create submodule directory %s", path);
 376                 sub = submodule_from_ce(ce);
 377                 if (sub)
 378                         return submodule_move_head(ce->name,
 379                                 NULL, oid_to_hex(&ce->oid),
 380                                 state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 381                 break;
 382
 383         default:
 384                 return error("unknown file mode for %s in index", ce->name);
 385         }
 386
 387 finish:
 388         if (state->refresh_cache) {
 389                 if (!fstat_done && lstat(ce->name, &st) < 0)
 390                         return error_errno("unable to stat just-written file %s",
 391                                            ce->name);
 392                 update_ce_after_write(state, ce , &st);
 393         }
 394 delayed:
 395         return 0;
 396 }
 397
 398 /*
 399  * This is like 'lstat()', except it refuses to follow symlinks
 400  * in the path, after skipping "skiplen".
 401  */
 402 static int check_path(const char *path, int len, struct stat *st, int skiplen)
 403 {
 404         const char *slash = path + len;
 405
 406         while (path < slash && *slash != '/')
 407                 slash--;
 408         if (!has_dirs_only_path(path, slash - path, skiplen)) {
 409                 errno = ENOENT;
 410                 return -1;
 411         }
 412         return lstat(path, st);
 413 }
 414
 415 static void mark_colliding_entries(const struct checkout *state,
 416                                    struct cache_entry *ce, struct stat *st)
 417 {
 418         int i, trust_ino = check_stat;
 419
 420 #if defined(GIT_WINDOWS_NATIVE) || defined(__CYGWIN__)
 421         trust_ino = 0;
 422 #endif
 423
 424         ce->ce_flags |= CE_MATCHED;
 425
 426         for (i = 0; i < state->istate->cache_nr; i++) {
 427                 struct cache_entry *dup = state->istate->cache[i];
 428
 429                 if (dup == ce)
 430                         break;
 431
 432                 if (dup->ce_flags & (CE_MATCHED | CE_VALID | CE_SKIP_WORKTREE))
 433                         continue;
 434
 435                 if ((trust_ino && !match_stat_data(&dup->ce_stat_data, st)) ||
 436                     (!trust_ino && !fspathcmp(ce->name, dup->name))) {
 437                         dup->ce_flags |= CE_MATCHED;
 438                         break;
 439                 }
 440         }
 441 }
 442
 443 int checkout_entry_ca(struct cache_entry *ce, struct conv_attrs *ca,
 444                       const struct checkout *state, char *topath,
 445                       int *nr_checkouts)
 446 {
 447         static struct strbuf path = STRBUF_INIT;
 448         struct stat st;
 449         struct conv_attrs ca_buf;
 450
 451         if (ce->ce_flags & CE_WT_REMOVE) {
 452                 if (topath)
 453                         /*
 454                          * No content and thus no path to create, so we have
 455                          * no pathname to return.
 456                          */
 457                         BUG("Can't remove entry to a path");
 458                 unlink_entry(ce);
 459                 return 0;
 460         }
 461
 462         if (topath) {
 463                 if (S_ISREG(ce->ce_mode) && !ca) {
 464                         convert_attrs(state->istate, &ca_buf, ce->name);
 465                         ca = &ca_buf;
 466                 }
 467                 return write_entry(ce, topath, ca, state, 1);
 468         }
 469
 470         strbuf_reset(&path);
 471         strbuf_add(&path, state->base_dir, state->base_dir_len);
 472         strbuf_add(&path, ce->name, ce_namelen(ce));
 473
 474         if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
 475                 const struct submodule *sub;
 476                 unsigned changed = ie_match_stat(state->istate, ce, &st,
 477                                                  CE_MATCH_IGNORE_VALID | CE_MATCH_IGNORE_SKIP_WORKTREE);
 478                 /*
 479                  * Needs to be checked before !changed returns early,
 480                  * as the possibly empty directory was not changed
 481                  */
 482                 sub = submodule_from_ce(ce);
 483                 if (sub) {
 484                         int err;
 485                         if (!is_submodule_populated_gently(ce->name, &err)) {
 486                                 struct stat sb;
 487                                 if (lstat(ce->name, &sb))
 488                                         die(_("could not stat file '%s'"), ce->name);
 489                                 if (!(st.st_mode & S_IFDIR))
 490                                         unlink_or_warn(ce->name);
 491
 492                                 return submodule_move_head(ce->name,
 493                                         NULL, oid_to_hex(&ce->oid), 0);
 494                         } else
 495                                 return submodule_move_head(ce->name,
 496                                         "HEAD", oid_to_hex(&ce->oid),
 497                                         state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 498                 }
 499
 500                 if (!changed)
 501                         return 0;
 502                 if (!state->force) {
 503                         if (!state->quiet)
 504                                 fprintf(stderr,
 505                                         "%s already exists, no checkout\n",
 506                                         path.buf);
 507                         return -1;
 508                 }
 509
 510                 if (state->clone)
 511                         mark_colliding_entries(state, ce, &st);
 512
 513                 /*
 514                  * We unlink the old file, to get the new one with the
 515                  * right permissions (including umask, which is nasty
 516                  * to emulate by hand - much easier to let the system
 517                  * just do the right thing)
 518                  */
 519                 if (S_ISDIR(st.st_mode)) {
 520                         /* If it is a gitlink, leave it alone! */
 521                         if (S_ISGITLINK(ce->ce_mode))
 522                                 return 0;
 523                         remove_subtree(&path);
 524                 } else if (unlink(path.buf))
 525                         return error_errno("unable to unlink old '%s'", path.buf);
 526         } else if (state->not_new)
 527                 return 0;
 528
 529         create_directories(path.buf, path.len, state);
 530
 531         if (nr_checkouts)
 532                 (*nr_checkouts)++;
 533
 534         if (S_ISREG(ce->ce_mode) && !ca) {
 535                 convert_attrs(state->istate, &ca_buf, ce->name);
 536                 ca = &ca_buf;
 537         }
 538
 539         return write_entry(ce, path.buf, ca, state, 0);
 540 }
 541
 542 void unlink_entry(const struct cache_entry *ce)
 543 {
 544         const struct submodule *sub = submodule_from_ce(ce);
 545         if (sub) {
 546                 /* state.force is set at the caller. */
 547                 submodule_move_head(ce->name, "HEAD", NULL,
 548                                     SUBMODULE_MOVE_HEAD_FORCE);
 549         }
 550         if (check_leading_path(ce->name, ce_namelen(ce), 1) >= 0)
 551                 return;
 552         if (remove_or_warn(ce->ce_mode, ce->name))
 553                 return;
 554         schedule_dir_for_removal(ce->name, ce_namelen(ce));
 555 }