entry.c

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