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 #include "parallel-checkout.h"
  11
  12 static void create_directories(const char *path, int path_len,
  13                                const struct checkout *state)
  14 {
  15         char *buf = xmallocz(path_len);
  16         int len = 0;
  17
  18         while (len < path_len) {
  19                 do {
  20                         buf[len] = path[len];
  21                         len++;
  22                 } while (len < path_len && path[len] != '/');
  23                 if (len >= path_len)
  24                         break;
  25                 buf[len] = 0;
  26
  27                 /*
  28                  * For 'checkout-index --prefix=<dir>', <dir> is
  29                  * allowed to be a symlink to an existing directory,
  30                  * and we set 'state->base_dir_len' below, such that
  31                  * we test the path components of the prefix with the
  32                  * stat() function instead of the lstat() function.
  33                  */
  34                 if (has_dirs_only_path(buf, len, state->base_dir_len))
  35                         continue; /* ok, it is already a directory. */
  36
  37                 /*
  38                  * If this mkdir() would fail, it could be that there
  39                  * is already a symlink or something else exists
  40                  * there, therefore we then try to unlink it and try
  41                  * one more time to create the directory.
  42                  */
  43                 if (mkdir(buf, 0777)) {
  44                         if (errno == EEXIST && state->force &&
  45                             !unlink_or_warn(buf) && !mkdir(buf, 0777))
  46                                 continue;
  47                         die_errno("cannot create directory at '%s'", buf);
  48                 }
  49         }
  50         free(buf);
  51 }
  52
  53 static void remove_subtree(struct strbuf *path)
  54 {
  55         DIR *dir = opendir(path->buf);
  56         struct dirent *de;
  57         int origlen = path->len;
  58
  59         if (!dir)
  60                 die_errno("cannot opendir '%s'", path->buf);
  61         while ((de = readdir_skip_dot_and_dotdot(dir)) != NULL) {
  62                 struct stat st;
  63
  64                 strbuf_addch(path, '/');
  65                 strbuf_addstr(path, de->d_name);
  66                 if (lstat(path->buf, &st))
  67                         die_errno("cannot lstat '%s'", path->buf);
  68                 if (S_ISDIR(st.st_mode))
  69                         remove_subtree(path);
  70                 else if (unlink(path->buf))
  71                         die_errno("cannot unlink '%s'", path->buf);
  72                 strbuf_setlen(path, origlen);
  73         }
  74         closedir(dir);
  75         if (rmdir(path->buf))
  76                 die_errno("cannot rmdir '%s'", path->buf);
  77 }
  78
  79 static int create_file(const char *path, unsigned int mode)
  80 {
  81         mode = (mode & 0100) ? 0777 : 0666;
  82         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
  83 }
  84
  85 void *read_blob_entry(const struct cache_entry *ce, size_t *size)
  86 {
  87         enum object_type type;
  88         unsigned long ul;
  89         void *blob_data = read_object_file(&ce->oid, &type, &ul);
  90
  91         *size = ul;
  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_nodup(&state->delayed_checkout->filters);
 149                 string_list_init_nodup(&state->delayed_checkout->paths);
 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 = item->util;
 161         return !available;
 162 }
 163
 164 int finish_delayed_checkout(struct checkout *state, int show_progress)
 165 {
 166         int errs = 0;
 167         unsigned processed_paths = 0;
 168         off_t filtered_bytes = 0;
 169         struct string_list_item *filter, *path;
 170         struct progress *progress = NULL;
 171         struct delayed_checkout *dco = state->delayed_checkout;
 172
 173         if (!state->delayed_checkout)
 174                 return errs;
 175
 176         dco->state = CE_RETRY;
 177         if (show_progress)
 178                 progress = start_delayed_progress(_("Filtering content"), dco->paths.nr);
 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
 183                         if (!async_query_available_blobs(filter->string, &available_paths)) {
 184                                 /* Filter reported an error */
 185                                 errs = 1;
 186                                 filter->string = "";
 187                                 continue;
 188                         }
 189                         if (available_paths.nr <= 0) {
 190                                 /*
 191                                  * Filter responded with no entries. That means
 192                                  * the filter is done and we can remove the
 193                                  * filter from the list (see
 194                                  * "string_list_remove_empty_items" call below).
 195                                  */
 196                                 filter->string = "";
 197                                 continue;
 198                         }
 199
 200                         /*
 201                          * In dco->paths we store a list of all delayed paths.
 202                          * The filter just send us a list of available paths.
 203                          * Remove them from the list.
 204                          */
 205                         filter_string_list(&dco->paths, 0,
 206                                 &remove_available_paths, &available_paths);
 207
 208                         for_each_string_list_item(path, &available_paths) {
 209                                 struct cache_entry* ce;
 210
 211                                 if (!path->util) {
 212                                         error("external filter '%s' signaled that '%s' "
 213                                               "is now available although it has not been "
 214                                               "delayed earlier",
 215                                               filter->string, path->string);
 216                                         errs |= 1;
 217
 218                                         /*
 219                                          * Do not ask the filter for available blobs,
 220                                          * again, as the filter is likely buggy.
 221                                          */
 222                                         filter->string = "";
 223                                         continue;
 224                                 }
 225                                 ce = index_file_exists(state->istate, path->string,
 226                                                        strlen(path->string), 0);
 227                                 if (ce) {
 228                                         display_progress(progress, ++processed_paths);
 229                                         errs |= checkout_entry(ce, state, NULL, path->util);
 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                        int *nr_checkouts)
 270 {
 271         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
 272         struct delayed_checkout *dco = state->delayed_checkout;
 273         int fd, ret, fstat_done = 0;
 274         char *new_blob;
 275         struct strbuf buf = STRBUF_INIT;
 276         size_t size;
 277         ssize_t wrote;
 278         size_t newsize = 0;
 279         struct stat st;
 280         const struct submodule *sub;
 281         struct checkout_metadata meta;
 282         static int scratch_nr_checkouts;
 283
 284         clone_checkout_metadata(&meta, &state->meta, &ce->oid);
 285
 286         if (ce_mode_s_ifmt == S_IFREG) {
 287                 struct stream_filter *filter = get_stream_filter_ca(ca, &ce->oid);
 288                 if (filter &&
 289                     !streaming_write_entry(ce, path, filter,
 290                                            state, to_tempfile,
 291                                            &fstat_done, &st))
 292                         goto finish;
 293         }
 294
 295         switch (ce_mode_s_ifmt) {
 296         case S_IFLNK:
 297                 new_blob = read_blob_entry(ce, &size);
 298                 if (!new_blob)
 299                         return error("unable to read sha1 file of %s (%s)",
 300                                      ce->name, oid_to_hex(&ce->oid));
 301
 302                 /*
 303                  * We can't make a real symlink; write out a regular file entry
 304                  * with the symlink destination as its contents.
 305                  */
 306                 if (!has_symlinks || to_tempfile)
 307                         goto write_file_entry;
 308
 309                 ret = symlink(new_blob, path);
 310                 free(new_blob);
 311                 if (ret)
 312                         return error_errno("unable to create symlink %s", path);
 313                 break;
 314
 315         case S_IFREG:
 316                 /*
 317                  * We do not send the blob in case of a retry, so do not
 318                  * bother reading it at all.
 319                  */
 320                 if (dco && dco->state == CE_RETRY) {
 321                         new_blob = NULL;
 322                         size = 0;
 323                 } else {
 324                         new_blob = read_blob_entry(ce, &size);
 325                         if (!new_blob)
 326                                 return error("unable to read sha1 file of %s (%s)",
 327                                              ce->name, oid_to_hex(&ce->oid));
 328                 }
 329
 330                 /*
 331                  * Convert from git internal format to working tree format
 332                  */
 333                 if (dco && dco->state != CE_NO_DELAY) {
 334                         ret = async_convert_to_working_tree_ca(ca, ce->name,
 335                                                                new_blob, size,
 336                                                                &buf, &meta, dco);
 337                         if (ret) {
 338                                 struct string_list_item *item =
 339                                         string_list_lookup(&dco->paths, ce->name);
 340                                 if (item) {
 341                                         item->util = nr_checkouts ? nr_checkouts
 342                                                         : &scratch_nr_checkouts;
 343                                         free(new_blob);
 344                                         goto delayed;
 345                                 }
 346                         }
 347                 } else {
 348                         ret = convert_to_working_tree_ca(ca, ce->name, new_blob,
 349                                                          size, &buf, &meta);
 350                 }
 351
 352                 if (ret) {
 353                         free(new_blob);
 354                         new_blob = strbuf_detach(&buf, &newsize);
 355                         size = newsize;
 356                 }
 357                 /*
 358                  * No "else" here as errors from convert are OK at this
 359                  * point. If the error would have been fatal (e.g.
 360                  * filter is required), then we would have died already.
 361                  */
 362
 363         write_file_entry:
 364                 fd = open_output_fd(path, ce, to_tempfile);
 365                 if (fd < 0) {
 366                         free(new_blob);
 367                         return error_errno("unable to create file %s", path);
 368                 }
 369
 370                 wrote = write_in_full(fd, new_blob, size);
 371                 if (!to_tempfile)
 372                         fstat_done = fstat_checkout_output(fd, state, &st);
 373                 close(fd);
 374                 free(new_blob);
 375                 if (wrote < 0)
 376                         return error("unable to write file %s", path);
 377                 break;
 378
 379         case S_IFGITLINK:
 380                 if (to_tempfile)
 381                         return error("cannot create temporary submodule %s", ce->name);
 382                 if (mkdir(path, 0777) < 0)
 383                         return error("cannot create submodule directory %s", path);
 384                 sub = submodule_from_ce(ce);
 385                 if (sub)
 386                         return submodule_move_head(ce->name,
 387                                 NULL, oid_to_hex(&ce->oid),
 388                                 state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 389                 break;
 390
 391         default:
 392                 return error("unknown file mode for %s in index", ce->name);
 393         }
 394
 395 finish:
 396         if (state->refresh_cache) {
 397                 if (!fstat_done && lstat(ce->name, &st) < 0)
 398                         return error_errno("unable to stat just-written file %s",
 399                                            ce->name);
 400                 update_ce_after_write(state, ce , &st);
 401         }
 402         if (nr_checkouts)
 403                 (*nr_checkouts)++;
 404 delayed:
 405         return 0;
 406 }
 407
 408 /*
 409  * This is like 'lstat()', except it refuses to follow symlinks
 410  * in the path, after skipping "skiplen".
 411  */
 412 static int check_path(const char *path, int len, struct stat *st, int skiplen)
 413 {
 414         const char *slash = path + len;
 415
 416         while (path < slash && *slash != '/')
 417                 slash--;
 418         if (!has_dirs_only_path(path, slash - path, skiplen)) {
 419                 errno = ENOENT;
 420                 return -1;
 421         }
 422         return lstat(path, st);
 423 }
 424
 425 static void mark_colliding_entries(const struct checkout *state,
 426                                    struct cache_entry *ce, struct stat *st)
 427 {
 428         int i, trust_ino = check_stat;
 429
 430 #if defined(GIT_WINDOWS_NATIVE) || defined(__CYGWIN__)
 431         trust_ino = 0;
 432 #endif
 433
 434         ce->ce_flags |= CE_MATCHED;
 435
 436         /* TODO: audit for interaction with sparse-index. */
 437         ensure_full_index(state->istate);
 438         for (i = 0; i < state->istate->cache_nr; i++) {
 439                 struct cache_entry *dup = state->istate->cache[i];
 440
 441                 if (dup == ce) {
 442                         /*
 443                          * Parallel checkout doesn't create the files in index
 444                          * order. So the other side of the collision may appear
 445                          * after the given cache_entry in the array.
 446                          */
 447                         if (parallel_checkout_status() == PC_RUNNING)
 448                                 continue;
 449                         else
 450                                 break;
 451                 }
 452
 453                 if (dup->ce_flags & (CE_MATCHED | CE_VALID | CE_SKIP_WORKTREE))
 454                         continue;
 455
 456                 if ((trust_ino && !match_stat_data(&dup->ce_stat_data, st)) ||
 457                     (!trust_ino && !fspathcmp(ce->name, dup->name))) {
 458                         dup->ce_flags |= CE_MATCHED;
 459                         break;
 460                 }
 461         }
 462 }
 463
 464 int checkout_entry_ca(struct cache_entry *ce, struct conv_attrs *ca,
 465                       const struct checkout *state, char *topath,
 466                       int *nr_checkouts)
 467 {
 468         static struct strbuf path = STRBUF_INIT;
 469         struct stat st;
 470         struct conv_attrs ca_buf;
 471
 472         if (ce->ce_flags & CE_WT_REMOVE) {
 473                 if (topath)
 474                         /*
 475                          * No content and thus no path to create, so we have
 476                          * no pathname to return.
 477                          */
 478                         BUG("Can't remove entry to a path");
 479                 unlink_entry(ce);
 480                 return 0;
 481         }
 482
 483         if (topath) {
 484                 if (S_ISREG(ce->ce_mode) && !ca) {
 485                         convert_attrs(state->istate, &ca_buf, ce->name);
 486                         ca = &ca_buf;
 487                 }
 488                 return write_entry(ce, topath, ca, state, 1, nr_checkouts);
 489         }
 490
 491         strbuf_reset(&path);
 492         strbuf_add(&path, state->base_dir, state->base_dir_len);
 493         strbuf_add(&path, ce->name, ce_namelen(ce));
 494
 495         if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
 496                 const struct submodule *sub;
 497                 unsigned changed = ie_match_stat(state->istate, ce, &st,
 498                                                  CE_MATCH_IGNORE_VALID | CE_MATCH_IGNORE_SKIP_WORKTREE);
 499                 /*
 500                  * Needs to be checked before !changed returns early,
 501                  * as the possibly empty directory was not changed
 502                  */
 503                 sub = submodule_from_ce(ce);
 504                 if (sub) {
 505                         int err;
 506                         if (!is_submodule_populated_gently(ce->name, &err)) {
 507                                 struct stat sb;
 508                                 if (lstat(ce->name, &sb))
 509                                         die(_("could not stat file '%s'"), ce->name);
 510                                 if (!(st.st_mode & S_IFDIR))
 511                                         unlink_or_warn(ce->name);
 512
 513                                 return submodule_move_head(ce->name,
 514                                         NULL, oid_to_hex(&ce->oid), 0);
 515                         } else
 516                                 return submodule_move_head(ce->name,
 517                                         "HEAD", oid_to_hex(&ce->oid),
 518                                         state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 519                 }
 520
 521                 if (!changed)
 522                         return 0;
 523                 if (!state->force) {
 524                         if (!state->quiet)
 525                                 fprintf(stderr,
 526                                         "%s already exists, no checkout\n",
 527                                         path.buf);
 528                         return -1;
 529                 }
 530
 531                 if (state->clone)
 532                         mark_colliding_entries(state, ce, &st);
 533
 534                 /*
 535                  * We unlink the old file, to get the new one with the
 536                  * right permissions (including umask, which is nasty
 537                  * to emulate by hand - much easier to let the system
 538                  * just do the right thing)
 539                  */
 540                 if (S_ISDIR(st.st_mode)) {
 541                         /* If it is a gitlink, leave it alone! */
 542                         if (S_ISGITLINK(ce->ce_mode))
 543                                 return 0;
 544                         remove_subtree(&path);
 545                 } else if (unlink(path.buf))
 546                         return error_errno("unable to unlink old '%s'", path.buf);
 547         } else if (state->not_new)
 548                 return 0;
 549
 550         create_directories(path.buf, path.len, state);
 551
 552         if (S_ISREG(ce->ce_mode) && !ca) {
 553                 convert_attrs(state->istate, &ca_buf, ce->name);
 554                 ca = &ca_buf;
 555         }
 556
 557         if (!enqueue_checkout(ce, ca, nr_checkouts))
 558                 return 0;
 559
 560         return write_entry(ce, path.buf, ca, state, 0, nr_checkouts);
 561 }
 562
 563 void unlink_entry(const struct cache_entry *ce)
 564 {
 565         const struct submodule *sub = submodule_from_ce(ce);
 566         if (sub) {
 567                 /* state.force is set at the caller. */
 568                 submodule_move_head(ce->name, "HEAD", NULL,
 569                                     SUBMODULE_MOVE_HEAD_FORCE);
 570         }
 571         if (check_leading_path(ce->name, ce_namelen(ce), 1) >= 0)
 572                 return;
 573         if (remove_or_warn(ce->ce_mode, ce->name))
 574                 return;
 575         schedule_dir_for_removal(ce->name, ce_namelen(ce));
 576 }