entry.c

   1 #include "cache.h"
   2 #include "blob.h"
   3 #include "object-store.h"
   4 #include "dir.h"
   5 #include "environment.h"
   6 #include "gettext.h"
   7 #include "hex.h"
   8 #include "streaming.h"
   9 #include "submodule.h"
  10 #include "progress.h"
  11 #include "fsmonitor.h"
  12 #include "entry.h"
  13 #include "parallel-checkout.h"
  14 #include "wrapper.h"
  15
  16 static void create_directories(const char *path, int path_len,
  17                                const struct checkout *state)
  18 {
  19         char *buf = xmallocz(path_len);
  20         int len = 0;
  21
  22         while (len < path_len) {
  23                 do {
  24                         buf[len] = path[len];
  25                         len++;
  26                 } while (len < path_len && path[len] != '/');
  27                 if (len >= path_len)
  28                         break;
  29                 buf[len] = 0;
  30
  31                 /*
  32                  * For 'checkout-index --prefix=<dir>', <dir> is
  33                  * allowed to be a symlink to an existing directory,
  34                  * and we set 'state->base_dir_len' below, such that
  35                  * we test the path components of the prefix with the
  36                  * stat() function instead of the lstat() function.
  37                  */
  38                 if (has_dirs_only_path(buf, len, state->base_dir_len))
  39                         continue; /* ok, it is already a directory. */
  40
  41                 /*
  42                  * If this mkdir() would fail, it could be that there
  43                  * is already a symlink or something else exists
  44                  * there, therefore we then try to unlink it and try
  45                  * one more time to create the directory.
  46                  */
  47                 if (mkdir(buf, 0777)) {
  48                         if (errno == EEXIST && state->force &&
  49                             !unlink_or_warn(buf) && !mkdir(buf, 0777))
  50                                 continue;
  51                         die_errno("cannot create directory at '%s'", buf);
  52                 }
  53         }
  54         free(buf);
  55 }
  56
  57 static void remove_subtree(struct strbuf *path)
  58 {
  59         DIR *dir = opendir(path->buf);
  60         struct dirent *de;
  61         int origlen = path->len;
  62
  63         if (!dir)
  64                 die_errno("cannot opendir '%s'", path->buf);
  65         while ((de = readdir_skip_dot_and_dotdot(dir)) != NULL) {
  66                 struct stat st;
  67
  68                 strbuf_addch(path, '/');
  69                 strbuf_addstr(path, de->d_name);
  70                 if (lstat(path->buf, &st))
  71                         die_errno("cannot lstat '%s'", path->buf);
  72                 if (S_ISDIR(st.st_mode))
  73                         remove_subtree(path);
  74                 else if (unlink(path->buf))
  75                         die_errno("cannot unlink '%s'", path->buf);
  76                 strbuf_setlen(path, origlen);
  77         }
  78         closedir(dir);
  79         if (rmdir(path->buf))
  80                 die_errno("cannot rmdir '%s'", path->buf);
  81 }
  82
  83 static int create_file(const char *path, unsigned int mode)
  84 {
  85         mode = (mode & 0100) ? 0777 : 0666;
  86         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
  87 }
  88
  89 void *read_blob_entry(const struct cache_entry *ce, size_t *size)
  90 {
  91         enum object_type type;
  92         unsigned long ul;
  93         void *blob_data = repo_read_object_file(the_repository, &ce->oid,
  94                                                 &type, &ul);
  95
  96         *size = ul;
  97         if (blob_data) {
  98                 if (type == OBJ_BLOB)
  99                         return blob_data;
 100                 free(blob_data);
 101         }
 102         return NULL;
 103 }
 104
 105 static int open_output_fd(char *path, const struct cache_entry *ce, int to_tempfile)
 106 {
 107         int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
 108         if (to_tempfile) {
 109                 xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
 110                           symlink ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
 111                 return mkstemp(path);
 112         } else {
 113                 return create_file(path, !symlink ? ce->ce_mode : 0666);
 114         }
 115 }
 116
 117 int fstat_checkout_output(int fd, const struct checkout *state, struct stat *st)
 118 {
 119         /* use fstat() only when path == ce->name */
 120         if (fstat_is_reliable() &&
 121             state->refresh_cache && !state->base_dir_len) {
 122                 return !fstat(fd, st);
 123         }
 124         return 0;
 125 }
 126
 127 static int streaming_write_entry(const struct cache_entry *ce, char *path,
 128                                  struct stream_filter *filter,
 129                                  const struct checkout *state, int to_tempfile,
 130                                  int *fstat_done, struct stat *statbuf)
 131 {
 132         int result = 0;
 133         int fd;
 134
 135         fd = open_output_fd(path, ce, to_tempfile);
 136         if (fd < 0)
 137                 return -1;
 138
 139         result |= stream_blob_to_fd(fd, &ce->oid, filter, 1);
 140         *fstat_done = fstat_checkout_output(fd, state, statbuf);
 141         result |= close(fd);
 142
 143         if (result)
 144                 unlink(path);
 145         return result;
 146 }
 147
 148 void enable_delayed_checkout(struct checkout *state)
 149 {
 150         if (!state->delayed_checkout) {
 151                 state->delayed_checkout = xmalloc(sizeof(*state->delayed_checkout));
 152                 state->delayed_checkout->state = CE_CAN_DELAY;
 153                 string_list_init_nodup(&state->delayed_checkout->filters);
 154                 string_list_init_nodup(&state->delayed_checkout->paths);
 155         }
 156 }
 157
 158 static int remove_available_paths(struct string_list_item *item, void *cb_data)
 159 {
 160         struct string_list *available_paths = cb_data;
 161         struct string_list_item *available;
 162
 163         available = string_list_lookup(available_paths, item->string);
 164         if (available)
 165                 available->util = item->util;
 166         return !available;
 167 }
 168
 169 int finish_delayed_checkout(struct checkout *state, int show_progress)
 170 {
 171         int errs = 0;
 172         unsigned processed_paths = 0;
 173         off_t filtered_bytes = 0;
 174         struct string_list_item *filter, *path;
 175         struct progress *progress = NULL;
 176         struct delayed_checkout *dco = state->delayed_checkout;
 177
 178         if (!state->delayed_checkout)
 179                 return errs;
 180
 181         dco->state = CE_RETRY;
 182         if (show_progress)
 183                 progress = start_delayed_progress(_("Filtering content"), dco->paths.nr);
 184         while (dco->filters.nr > 0) {
 185                 for_each_string_list_item(filter, &dco->filters) {
 186                         struct string_list available_paths = STRING_LIST_INIT_NODUP;
 187
 188                         if (!async_query_available_blobs(filter->string, &available_paths)) {
 189                                 /* Filter reported an error */
 190                                 errs = 1;
 191                                 filter->string = "";
 192                                 continue;
 193                         }
 194                         if (available_paths.nr <= 0) {
 195                                 /*
 196                                  * Filter responded with no entries. That means
 197                                  * the filter is done and we can remove the
 198                                  * filter from the list (see
 199                                  * "string_list_remove_empty_items" call below).
 200                                  */
 201                                 filter->string = "";
 202                                 continue;
 203                         }
 204
 205                         /*
 206                          * In dco->paths we store a list of all delayed paths.
 207                          * The filter just send us a list of available paths.
 208                          * Remove them from the list.
 209                          */
 210                         filter_string_list(&dco->paths, 0,
 211                                 &remove_available_paths, &available_paths);
 212
 213                         for_each_string_list_item(path, &available_paths) {
 214                                 struct cache_entry* ce;
 215
 216                                 if (!path->util) {
 217                                         error("external filter '%s' signaled that '%s' "
 218                                               "is now available although it has not been "
 219                                               "delayed earlier",
 220                                               filter->string, path->string);
 221                                         errs |= 1;
 222
 223                                         /*
 224                                          * Do not ask the filter for available blobs,
 225                                          * again, as the filter is likely buggy.
 226                                          */
 227                                         filter->string = "";
 228                                         continue;
 229                                 }
 230                                 ce = index_file_exists(state->istate, path->string,
 231                                                        strlen(path->string), 0);
 232                                 if (ce) {
 233                                         display_progress(progress, ++processed_paths);
 234                                         errs |= checkout_entry(ce, state, NULL, path->util);
 235                                         filtered_bytes += ce->ce_stat_data.sd_size;
 236                                         display_throughput(progress, filtered_bytes);
 237                                 } else
 238                                         errs = 1;
 239                         }
 240                 }
 241                 string_list_remove_empty_items(&dco->filters, 0);
 242         }
 243         stop_progress(&progress);
 244         string_list_clear(&dco->filters, 0);
 245
 246         /* At this point we should not have any delayed paths anymore. */
 247         errs |= dco->paths.nr;
 248         for_each_string_list_item(path, &dco->paths) {
 249                 error("'%s' was not filtered properly", path->string);
 250         }
 251         string_list_clear(&dco->paths, 0);
 252
 253         free(dco);
 254         state->delayed_checkout = NULL;
 255
 256         return errs;
 257 }
 258
 259 void update_ce_after_write(const struct checkout *state, struct cache_entry *ce,
 260                            struct stat *st)
 261 {
 262         if (state->refresh_cache) {
 263                 assert(state->istate);
 264                 fill_stat_cache_info(state->istate, ce, st);
 265                 ce->ce_flags |= CE_UPDATE_IN_BASE;
 266                 mark_fsmonitor_invalid(state->istate, ce);
 267                 state->istate->cache_changed |= CE_ENTRY_CHANGED;
 268         }
 269 }
 270
 271 /* Note: ca is used (and required) iff the entry refers to a regular file. */
 272 static int write_entry(struct cache_entry *ce, char *path, struct conv_attrs *ca,
 273                        const struct checkout *state, int to_tempfile,
 274                        int *nr_checkouts)
 275 {
 276         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
 277         struct delayed_checkout *dco = state->delayed_checkout;
 278         int fd, ret, fstat_done = 0;
 279         char *new_blob;
 280         struct strbuf buf = STRBUF_INIT;
 281         size_t size;
 282         ssize_t wrote;
 283         size_t newsize = 0;
 284         struct stat st;
 285         const struct submodule *sub;
 286         struct checkout_metadata meta;
 287         static int scratch_nr_checkouts;
 288
 289         clone_checkout_metadata(&meta, &state->meta, &ce->oid);
 290
 291         if (ce_mode_s_ifmt == S_IFREG) {
 292                 struct stream_filter *filter = get_stream_filter_ca(ca, &ce->oid);
 293                 if (filter &&
 294                     !streaming_write_entry(ce, path, filter,
 295                                            state, to_tempfile,
 296                                            &fstat_done, &st))
 297                         goto finish;
 298         }
 299
 300         switch (ce_mode_s_ifmt) {
 301         case S_IFLNK:
 302                 new_blob = read_blob_entry(ce, &size);
 303                 if (!new_blob)
 304                         return error("unable to read sha1 file of %s (%s)",
 305                                      ce->name, oid_to_hex(&ce->oid));
 306
 307                 /*
 308                  * We can't make a real symlink; write out a regular file entry
 309                  * with the symlink destination as its contents.
 310                  */
 311                 if (!has_symlinks || to_tempfile)
 312                         goto write_file_entry;
 313
 314                 ret = symlink(new_blob, path);
 315                 free(new_blob);
 316                 if (ret)
 317                         return error_errno("unable to create symlink %s", path);
 318                 break;
 319
 320         case S_IFREG:
 321                 /*
 322                  * We do not send the blob in case of a retry, so do not
 323                  * bother reading it at all.
 324                  */
 325                 if (dco && dco->state == CE_RETRY) {
 326                         new_blob = NULL;
 327                         size = 0;
 328                 } else {
 329                         new_blob = read_blob_entry(ce, &size);
 330                         if (!new_blob)
 331                                 return error("unable to read sha1 file of %s (%s)",
 332                                              ce->name, oid_to_hex(&ce->oid));
 333                 }
 334
 335                 /*
 336                  * Convert from git internal format to working tree format
 337                  */
 338                 if (dco && dco->state != CE_NO_DELAY) {
 339                         ret = async_convert_to_working_tree_ca(ca, ce->name,
 340                                                                new_blob, size,
 341                                                                &buf, &meta, dco);
 342                         if (ret) {
 343                                 struct string_list_item *item =
 344                                         string_list_lookup(&dco->paths, ce->name);
 345                                 if (item) {
 346                                         item->util = nr_checkouts ? nr_checkouts
 347                                                         : &scratch_nr_checkouts;
 348                                         free(new_blob);
 349                                         goto delayed;
 350                                 }
 351                         }
 352                 } else {
 353                         ret = convert_to_working_tree_ca(ca, ce->name, new_blob,
 354                                                          size, &buf, &meta);
 355                 }
 356
 357                 if (ret) {
 358                         free(new_blob);
 359                         new_blob = strbuf_detach(&buf, &newsize);
 360                         size = newsize;
 361                 }
 362                 /*
 363                  * No "else" here as errors from convert are OK at this
 364                  * point. If the error would have been fatal (e.g.
 365                  * filter is required), then we would have died already.
 366                  */
 367
 368         write_file_entry:
 369                 fd = open_output_fd(path, ce, to_tempfile);
 370                 if (fd < 0) {
 371                         free(new_blob);
 372                         return error_errno("unable to create file %s", path);
 373                 }
 374
 375                 wrote = write_in_full(fd, new_blob, size);
 376                 if (!to_tempfile)
 377                         fstat_done = fstat_checkout_output(fd, state, &st);
 378                 close(fd);
 379                 free(new_blob);
 380                 if (wrote < 0)
 381                         return error("unable to write file %s", path);
 382                 break;
 383
 384         case S_IFGITLINK:
 385                 if (to_tempfile)
 386                         return error("cannot create temporary submodule %s", ce->name);
 387                 if (mkdir(path, 0777) < 0)
 388                         return error("cannot create submodule directory %s", path);
 389                 sub = submodule_from_ce(ce);
 390                 if (sub)
 391                         return submodule_move_head(ce->name, state->super_prefix,
 392                                 NULL, oid_to_hex(&ce->oid),
 393                                 state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 394                 break;
 395
 396         default:
 397                 return error("unknown file mode for %s in index", ce->name);
 398         }
 399
 400 finish:
 401         if (state->refresh_cache) {
 402                 if (!fstat_done && lstat(ce->name, &st) < 0)
 403                         return error_errno("unable to stat just-written file %s",
 404                                            ce->name);
 405                 update_ce_after_write(state, ce , &st);
 406         }
 407         if (nr_checkouts)
 408                 (*nr_checkouts)++;
 409 delayed:
 410         return 0;
 411 }
 412
 413 /*
 414  * This is like 'lstat()', except it refuses to follow symlinks
 415  * in the path, after skipping "skiplen".
 416  */
 417 static int check_path(const char *path, int len, struct stat *st, int skiplen)
 418 {
 419         const char *slash = path + len;
 420
 421         while (path < slash && *slash != '/')
 422                 slash--;
 423         if (!has_dirs_only_path(path, slash - path, skiplen)) {
 424                 errno = ENOENT;
 425                 return -1;
 426         }
 427         return lstat(path, st);
 428 }
 429
 430 static void mark_colliding_entries(const struct checkout *state,
 431                                    struct cache_entry *ce, struct stat *st)
 432 {
 433         int i, trust_ino = check_stat;
 434
 435 #if defined(GIT_WINDOWS_NATIVE) || defined(__CYGWIN__)
 436         trust_ino = 0;
 437 #endif
 438
 439         ce->ce_flags |= CE_MATCHED;
 440
 441         /* TODO: audit for interaction with sparse-index. */
 442         ensure_full_index(state->istate);
 443         for (i = 0; i < state->istate->cache_nr; i++) {
 444                 struct cache_entry *dup = state->istate->cache[i];
 445
 446                 if (dup == ce) {
 447                         /*
 448                          * Parallel checkout doesn't create the files in index
 449                          * order. So the other side of the collision may appear
 450                          * after the given cache_entry in the array.
 451                          */
 452                         if (parallel_checkout_status() == PC_RUNNING)
 453                                 continue;
 454                         else
 455                                 break;
 456                 }
 457
 458                 if (dup->ce_flags & (CE_MATCHED | CE_VALID | CE_SKIP_WORKTREE))
 459                         continue;
 460
 461                 if ((trust_ino && !match_stat_data(&dup->ce_stat_data, st)) ||
 462                     (!trust_ino && !fspathcmp(ce->name, dup->name))) {
 463                         dup->ce_flags |= CE_MATCHED;
 464                         break;
 465                 }
 466         }
 467 }
 468
 469 int checkout_entry_ca(struct cache_entry *ce, struct conv_attrs *ca,
 470                       const struct checkout *state, char *topath,
 471                       int *nr_checkouts)
 472 {
 473         static struct strbuf path = STRBUF_INIT;
 474         struct stat st;
 475         struct conv_attrs ca_buf;
 476
 477         if (ce->ce_flags & CE_WT_REMOVE) {
 478                 if (topath)
 479                         /*
 480                          * No content and thus no path to create, so we have
 481                          * no pathname to return.
 482                          */
 483                         BUG("Can't remove entry to a path");
 484                 unlink_entry(ce, state->super_prefix);
 485                 return 0;
 486         }
 487
 488         if (topath) {
 489                 if (S_ISREG(ce->ce_mode) && !ca) {
 490                         convert_attrs(state->istate, &ca_buf, ce->name);
 491                         ca = &ca_buf;
 492                 }
 493                 return write_entry(ce, topath, ca, state, 1, nr_checkouts);
 494         }
 495
 496         strbuf_reset(&path);
 497         strbuf_add(&path, state->base_dir, state->base_dir_len);
 498         strbuf_add(&path, ce->name, ce_namelen(ce));
 499
 500         if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
 501                 const struct submodule *sub;
 502                 unsigned changed = ie_match_stat(state->istate, ce, &st,
 503                                                  CE_MATCH_IGNORE_VALID | CE_MATCH_IGNORE_SKIP_WORKTREE);
 504                 /*
 505                  * Needs to be checked before !changed returns early,
 506                  * as the possibly empty directory was not changed
 507                  */
 508                 sub = submodule_from_ce(ce);
 509                 if (sub) {
 510                         int err;
 511                         if (!is_submodule_populated_gently(ce->name, &err)) {
 512                                 struct stat sb;
 513                                 if (lstat(ce->name, &sb))
 514                                         die(_("could not stat file '%s'"), ce->name);
 515                                 if (!(st.st_mode & S_IFDIR))
 516                                         unlink_or_warn(ce->name);
 517
 518                                 return submodule_move_head(ce->name, state->super_prefix,
 519                                         NULL, oid_to_hex(&ce->oid), 0);
 520                         } else
 521                                 return submodule_move_head(ce->name, state->super_prefix,
 522                                         "HEAD", oid_to_hex(&ce->oid),
 523                                         state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 524                 }
 525
 526                 if (!changed)
 527                         return 0;
 528                 if (!state->force) {
 529                         if (!state->quiet)
 530                                 fprintf(stderr,
 531                                         "%s already exists, no checkout\n",
 532                                         path.buf);
 533                         return -1;
 534                 }
 535
 536                 if (state->clone)
 537                         mark_colliding_entries(state, ce, &st);
 538
 539                 /*
 540                  * We unlink the old file, to get the new one with the
 541                  * right permissions (including umask, which is nasty
 542                  * to emulate by hand - much easier to let the system
 543                  * just do the right thing)
 544                  */
 545                 if (S_ISDIR(st.st_mode)) {
 546                         /* If it is a gitlink, leave it alone! */
 547                         if (S_ISGITLINK(ce->ce_mode))
 548                                 return 0;
 549                         remove_subtree(&path);
 550                 } else if (unlink(path.buf))
 551                         return error_errno("unable to unlink old '%s'", path.buf);
 552         } else if (state->not_new)
 553                 return 0;
 554
 555         create_directories(path.buf, path.len, state);
 556
 557         if (S_ISREG(ce->ce_mode) && !ca) {
 558                 convert_attrs(state->istate, &ca_buf, ce->name);
 559                 ca = &ca_buf;
 560         }
 561
 562         if (!enqueue_checkout(ce, ca, nr_checkouts))
 563                 return 0;
 564
 565         return write_entry(ce, path.buf, ca, state, 0, nr_checkouts);
 566 }
 567
 568 void unlink_entry(const struct cache_entry *ce, const char *super_prefix)
 569 {
 570         const struct submodule *sub = submodule_from_ce(ce);
 571         if (sub) {
 572                 /* state.force is set at the caller. */
 573                 submodule_move_head(ce->name, super_prefix, "HEAD", NULL,
 574                                     SUBMODULE_MOVE_HEAD_FORCE);
 575         }
 576         if (check_leading_path(ce->name, ce_namelen(ce), 1) >= 0)
 577                 return;
 578         if (remove_or_warn(ce->ce_mode, ce->name))
 579                 return;
 580         schedule_dir_for_removal(ce->name, ce_namelen(ce));
 581 }