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