lib/vfs/direntry.c

   1 /*
   2    Directory cache support
   3
   4    Copyright (C) 1998-2017
   5    Free Software Foundation, Inc.
   6
   7    Written by:
   8    Pavel Machek <pavel@ucw.cz>, 1998
   9    Slava Zanko <slavazanko@gmail.com>, 2013
  10
  11    This file is part of the Midnight Commander.
  12
  13    The Midnight Commander is free software: you can redistribute it
  14    and/or modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation, either version 3 of the License,
  16    or (at your option) any later version.
  17
  18    The Midnight Commander is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21    GNU General Public License for more details.
  22
  23    You should have received a copy of the GNU General Public License
  24    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25
  26    \warning Paths here do _not_ begin with '/', so root directory of
  27    archive/site is simply "".
  28  */
  29
  30 /** \file
  31  *  \brief Source: directory cache support
  32  *
  33  *  So that you do not have copy of this in each and every filesystem.
  34  *
  35  *  Very loosely based on tar.c from midnight and archives.[ch] from
  36  *  avfs by Miklos Szeredi (mszeredi@inf.bme.hu)
  37  *
  38  *  Unfortunately, I was unable to keep all filesystems
  39  *  uniform. tar-like filesystems use tree structure where each
  40  *  directory has pointers to its subdirectories. We can do this
  41  *  because we have full information about our archive.
  42  *
  43  *  At ftp-like filesystems, situation is a little bit different. When
  44  *  you cd /usr/src/linux/drivers/char, you do _not_ want /usr,
  45  *  /usr/src, /usr/src/linux and /usr/src/linux/drivers to be
  46  *  listed. That means that we do not have complete information, and if
  47  *  /usr is symlink to /4, we will not know. Also we have to time out
  48  *  entries and things would get messy with tree-like approach. So we
  49  *  do different trick: root directory is completely special and
  50  *  completely fake, it contains entries such as 'usr', 'usr/src', ...,
  51  *  and we'll try to use custom find_entry function.
  52  *
  53  *  \author Pavel Machek <pavel@ucw.cz>
  54  *  \date 1998
  55  *
  56  */
  57
  58 #include <config.h>
  59
  60 #include <errno.h>
  61 #include <time.h>
  62 #include <sys/time.h>           /* gettimeofday() */
  63 #include <inttypes.h>           /* uintmax_t */
  64 #include <stdarg.h>
  65
  66 #include "lib/global.h"
  67
  68 #include "lib/tty/tty.h"        /* enable/disable interrupt key */
  69 #include "lib/util.h"           /* custom_canonicalize_pathname() */
  70 #if 0
  71 #include "lib/widget.h"         /* message() */
  72 #endif
  73
  74 #include "vfs.h"
  75 #include "utilvfs.h"
  76 #include "xdirentry.h"
  77 #include "gc.h"                 /* vfs_rmstamp */
  78
  79 /*** global variables ****************************************************************************/
  80
  81 /*** file scope macro definitions ****************************************************************/
  82
  83 #define CALL(x) if (MEDATA->x) MEDATA->x
  84
  85 /*** file scope type declarations ****************************************************************/
  86
  87 struct dirhandle
  88 {
  89     GList *cur;
  90     struct vfs_s_inode *dir;
  91 };
  92
  93 /*** file scope variables ************************************************************************/
  94
  95 /*** file scope functions ************************************************************************/
  96 /* --------------------------------------------------------------------------------------------- */
  97
  98 static int
  99 vfs_s_entry_compare (const void *a, const void *b)
 100 {
 101     const struct vfs_s_entry *e = (const struct vfs_s_entry *) a;
 102     const char *name = (const char *) b;
 103
 104     return strcmp (e->name, name);
 105 }
 106
 107 /* --------------------------------------------------------------------------------------------- */
 108
 109 /* We were asked to create entries automagically */
 110
 111 static struct vfs_s_entry *
 112 vfs_s_automake (struct vfs_class *me, struct vfs_s_inode *dir, char *path, int flags)
 113 {
 114     struct vfs_s_entry *res;
 115     char *sep;
 116
 117     sep = strchr (path, PATH_SEP);
 118     if (sep != NULL)
 119         *sep = '\0';
 120
 121     res = vfs_s_generate_entry (me, path, dir, (flags & FL_MKDIR) != 0 ? (0777 | S_IFDIR) : 0777);
 122     vfs_s_insert_entry (me, dir, res);
 123
 124     if (sep != NULL)
 125         *sep = PATH_SEP;
 126
 127     return res;
 128 }
 129
 130 /* --------------------------------------------------------------------------------------------- */
 131 /* If the entry is a symlink, find the entry for its target */
 132
 133 static struct vfs_s_entry *
 134 vfs_s_resolve_symlink (struct vfs_class *me, struct vfs_s_entry *entry, int follow)
 135 {
 136     char *linkname;
 137     char *fullname = NULL;
 138     struct vfs_s_entry *target;
 139
 140     if (follow == LINK_NO_FOLLOW)
 141         return entry;
 142     if (follow == 0)
 143         ERRNOR (ELOOP, NULL);
 144     if (!entry)
 145         ERRNOR (ENOENT, NULL);
 146     if (!S_ISLNK (entry->ino->st.st_mode))
 147         return entry;
 148
 149     linkname = entry->ino->linkname;
 150     if (linkname == NULL)
 151         ERRNOR (EFAULT, NULL);
 152
 153     /* make full path from relative */
 154     if (!IS_PATH_SEP (*linkname))
 155     {
 156         char *fullpath;
 157
 158         fullpath = vfs_s_fullpath (me, entry->dir);
 159         if (fullpath != NULL)
 160         {
 161             fullname = g_strconcat (fullpath, PATH_SEP_STR, linkname, (char *) NULL);
 162             linkname = fullname;
 163             g_free (fullpath);
 164         }
 165     }
 166
 167     target = (MEDATA->find_entry) (me, entry->dir->super->root, linkname, follow - 1, 0);
 168     g_free (fullname);
 169     return target;
 170 }
 171
 172 /* --------------------------------------------------------------------------------------------- */
 173 /*
 174  * Follow > 0: follow links, serves as loop protect,
 175  *       == -1: do not follow links
 176  */
 177
 178 static struct vfs_s_entry *
 179 vfs_s_find_entry_tree (struct vfs_class *me, struct vfs_s_inode *root,
 180                        const char *a_path, int follow, int flags)
 181 {
 182     size_t pseg;
 183     struct vfs_s_entry *ent = NULL;
 184     char *const pathref = g_strdup (a_path);
 185     char *path = pathref;
 186
 187     /* canonicalize as well, but don't remove '../' from path */
 188     custom_canonicalize_pathname (path, CANON_PATH_ALL & (~CANON_PATH_REMDOUBLEDOTS));
 189
 190     while (root != NULL)
 191     {
 192         GList *iter;
 193
 194         while (IS_PATH_SEP (*path))     /* Strip leading '/' */
 195             path++;
 196
 197         if (path[0] == '\0')
 198         {
 199             g_free (pathref);
 200             return ent;
 201         }
 202
 203         for (pseg = 0; path[pseg] != '\0' && !IS_PATH_SEP (path[pseg]); pseg++)
 204             ;
 205
 206         for (iter = root->subdir; iter != NULL; iter = g_list_next (iter))
 207         {
 208             ent = (struct vfs_s_entry *) iter->data;
 209             if (strlen (ent->name) == pseg && strncmp (ent->name, path, pseg) == 0)
 210                 /* FOUND! */
 211                 break;
 212         }
 213
 214         ent = iter != NULL ? (struct vfs_s_entry *) iter->data : NULL;
 215
 216         if (ent == NULL && (flags & (FL_MKFILE | FL_MKDIR)) != 0)
 217             ent = vfs_s_automake (me, root, path, flags);
 218         if (ent == NULL)
 219         {
 220             me->verrno = ENOENT;
 221             goto cleanup;
 222         }
 223
 224         path += pseg;
 225         /* here we must follow leading directories always;
 226            only the actual file is optional */
 227         ent = vfs_s_resolve_symlink (me, ent,
 228                                      strchr (path, PATH_SEP) != NULL ? LINK_FOLLOW : follow);
 229         if (ent == NULL)
 230             goto cleanup;
 231         root = ent->ino;
 232     }
 233   cleanup:
 234     g_free (pathref);
 235     return NULL;
 236 }
 237
 238 /* --------------------------------------------------------------------------------------------- */
 239
 240 static struct vfs_s_entry *
 241 vfs_s_find_entry_linear (struct vfs_class *me, struct vfs_s_inode *root,
 242                          const char *a_path, int follow, int flags)
 243 {
 244     struct vfs_s_entry *ent = NULL;
 245     char *const path = g_strdup (a_path);
 246     GList *iter;
 247
 248     if (root->super->root != root)
 249         vfs_die ("We have to use _real_ root. Always. Sorry.");
 250
 251     /* canonicalize as well, but don't remove '../' from path */
 252     custom_canonicalize_pathname (path, CANON_PATH_ALL & (~CANON_PATH_REMDOUBLEDOTS));
 253
 254     if ((flags & FL_DIR) == 0)
 255     {
 256         char *dirname, *name;
 257         struct vfs_s_inode *ino;
 258
 259         dirname = g_path_get_dirname (path);
 260         name = g_path_get_basename (path);
 261         ino = vfs_s_find_inode (me, root->super, dirname, follow, flags | FL_DIR);
 262         ent = vfs_s_find_entry_tree (me, ino, name, follow, flags);
 263         g_free (dirname);
 264         g_free (name);
 265         g_free (path);
 266         return ent;
 267     }
 268
 269     iter = g_list_find_custom (root->subdir, path, (GCompareFunc) vfs_s_entry_compare);
 270     ent = iter != NULL ? (struct vfs_s_entry *) iter->data : NULL;
 271
 272     if (ent != NULL && !MEDATA->dir_uptodate (me, ent->ino))
 273     {
 274 #if 1
 275         vfs_print_message (_("Directory cache expired for %s"), path);
 276 #endif
 277         vfs_s_free_entry (me, ent);
 278         ent = NULL;
 279     }
 280
 281     if (ent == NULL)
 282     {
 283         struct vfs_s_inode *ino;
 284
 285         ino = vfs_s_new_inode (me, root->super, vfs_s_default_stat (me, S_IFDIR | 0755));
 286         ent = vfs_s_new_entry (me, path, ino);
 287         if (MEDATA->dir_load (me, ino, path) == -1)
 288         {
 289             vfs_s_free_entry (me, ent);
 290             g_free (path);
 291             return NULL;
 292         }
 293
 294         vfs_s_insert_entry (me, root, ent);
 295
 296         iter = g_list_find_custom (root->subdir, path, (GCompareFunc) vfs_s_entry_compare);
 297         ent = iter != NULL ? (struct vfs_s_entry *) iter->data : NULL;
 298     }
 299     if (ent == NULL)
 300         vfs_die ("find_linear: success but directory is not there\n");
 301
 302 #if 0
 303     if (!vfs_s_resolve_symlink (me, ent, follow))
 304     {
 305         g_free (path);
 306         return NULL;
 307     }
 308 #endif
 309     g_free (path);
 310     return ent;
 311 }
 312
 313 /* --------------------------------------------------------------------------------------------- */
 314 /* Ook, these were functions around directory entries / inodes */
 315 /* -------------------------------- superblock games -------------------------- */
 316
 317 static struct vfs_s_super *
 318 vfs_s_new_super (struct vfs_class *me)
 319 {
 320     struct vfs_s_super *super;
 321
 322     super = g_new0 (struct vfs_s_super, 1);
 323     super->me = me;
 324     return super;
 325 }
 326
 327 /* --------------------------------------------------------------------------------------------- */
 328
 329 static inline void
 330 vfs_s_insert_super (struct vfs_class *me, struct vfs_s_super *super)
 331 {
 332     MEDATA->supers = g_list_prepend (MEDATA->supers, super);
 333 }
 334
 335 /* --------------------------------------------------------------------------------------------- */
 336
 337 static void
 338 vfs_s_free_super (struct vfs_class *me, struct vfs_s_super *super)
 339 {
 340     if (super->root != NULL)
 341     {
 342         vfs_s_free_inode (me, super->root);
 343         super->root = NULL;
 344     }
 345
 346 #if 0
 347     /* FIXME: We currently leak small ammount of memory, sometimes. Fix it if you can. */
 348     if (super->ino_usage)
 349         message (D_ERROR, "Direntry warning",
 350                  "Super ino_usage is %d, memory leak", super->ino_usage);
 351
 352     if (super->want_stale)
 353         message (D_ERROR, "Direntry warning", "%s", "Super has want_stale set");
 354 #endif
 355
 356     MEDATA->supers = g_list_remove (MEDATA->supers, super);
 357
 358     CALL (free_archive) (me, super);
 359 #ifdef ENABLE_VFS_NET
 360     vfs_path_element_free (super->path_element);
 361 #endif
 362     g_free (super->name);
 363     g_free (super);
 364 }
 365
 366 /* --------------------------------------------------------------------------------------------- */
 367 /* Support of archives */
 368 /* ------------------------ readdir & friends ----------------------------- */
 369
 370 static struct vfs_s_inode *
 371 vfs_s_inode_from_path (const vfs_path_t * vpath, int flags)
 372 {
 373     struct vfs_s_super *super;
 374     struct vfs_s_inode *ino;
 375     const char *q;
 376     const vfs_path_element_t *path_element;
 377
 378     q = vfs_s_get_path (vpath, &super, 0);
 379     if (q == NULL)
 380         return NULL;
 381
 382     path_element = vfs_path_get_by_index (vpath, -1);
 383
 384     ino =
 385         vfs_s_find_inode (path_element->class, super, q,
 386                           (flags & FL_FOLLOW) != 0 ? LINK_FOLLOW : LINK_NO_FOLLOW,
 387                           flags & ~FL_FOLLOW);
 388     if ((!ino) && (!*q))
 389         /* We are asking about / directory of ftp server: assume it exists */
 390         ino =
 391             vfs_s_find_inode (path_element->class, super, q,
 392                               (flags & FL_FOLLOW) != 0 ? LINK_FOLLOW : LINK_NO_FOLLOW,
 393                               FL_DIR | (flags & ~FL_FOLLOW));
 394     return ino;
 395 }
 396
 397 /* --------------------------------------------------------------------------------------------- */
 398
 399 static void *
 400 vfs_s_opendir (const vfs_path_t * vpath)
 401 {
 402     struct vfs_s_inode *dir;
 403     struct dirhandle *info;
 404     const vfs_path_element_t *path_element;
 405
 406     path_element = vfs_path_get_by_index (vpath, -1);
 407
 408     dir = vfs_s_inode_from_path (vpath, FL_DIR | FL_FOLLOW);
 409     if (dir == NULL)
 410         return NULL;
 411     if (!S_ISDIR (dir->st.st_mode))
 412     {
 413         path_element->class->verrno = ENOTDIR;
 414         return NULL;
 415     }
 416
 417     dir->st.st_nlink++;
 418 #if 0
 419     if (dir->subdir == NULL)    /* This can actually happen if we allow empty directories */
 420     {
 421         path_element->class->verrno = EAGAIN;
 422         return NULL;
 423     }
 424 #endif
 425     info = g_new (struct dirhandle, 1);
 426     info->cur = dir->subdir;
 427     info->dir = dir;
 428
 429     return info;
 430 }
 431
 432 /* --------------------------------------------------------------------------------------------- */
 433
 434 static void *
 435 vfs_s_readdir (void *data)
 436 {
 437     static union vfs_dirent dir;
 438     struct dirhandle *info = (struct dirhandle *) data;
 439     const char *name;
 440
 441     if (info->cur == NULL || info->cur->data == NULL)
 442         return NULL;
 443
 444     name = ((struct vfs_s_entry *) info->cur->data)->name;
 445     if (name != NULL)
 446         g_strlcpy (dir.dent.d_name, name, MC_MAXPATHLEN);
 447     else
 448         vfs_die ("Null in structure-cannot happen");
 449
 450     info->cur = g_list_next (info->cur);
 451
 452     return (void *) &dir;
 453 }
 454
 455 /* --------------------------------------------------------------------------------------------- */
 456
 457 static int
 458 vfs_s_closedir (void *data)
 459 {
 460     struct dirhandle *info = (struct dirhandle *) data;
 461     struct vfs_s_inode *dir = info->dir;
 462
 463     vfs_s_free_inode (dir->super->me, dir);
 464     g_free (data);
 465     return 0;
 466 }
 467
 468 /* --------------------------------------------------------------------------------------------- */
 469
 470 static int
 471 vfs_s_chdir (const vfs_path_t * vpath)
 472 {
 473     void *data;
 474
 475     data = vfs_s_opendir (vpath);
 476     if (data == NULL)
 477         return -1;
 478     vfs_s_closedir (data);
 479     return 0;
 480 }
 481
 482 /* --------------------------------------------------------------------------------------------- */
 483 /* --------------------------- stat and friends ---------------------------- */
 484
 485 static int
 486 vfs_s_internal_stat (const vfs_path_t * vpath, struct stat *buf, int flag)
 487 {
 488     struct vfs_s_inode *ino;
 489
 490     ino = vfs_s_inode_from_path (vpath, flag);
 491     if (ino == NULL)
 492         return -1;
 493     *buf = ino->st;
 494     return 0;
 495 }
 496
 497 /* --------------------------------------------------------------------------------------------- */
 498
 499 static int
 500 vfs_s_readlink (const vfs_path_t * vpath, char *buf, size_t size)
 501 {
 502     struct vfs_s_inode *ino;
 503     size_t len;
 504     const vfs_path_element_t *path_element;
 505
 506     path_element = vfs_path_get_by_index (vpath, -1);
 507
 508     ino = vfs_s_inode_from_path (vpath, 0);
 509     if (!ino)
 510         return -1;
 511
 512     if (!S_ISLNK (ino->st.st_mode))
 513     {
 514         path_element->class->verrno = EINVAL;
 515         return -1;
 516     }
 517
 518     if (ino->linkname == NULL)
 519     {
 520         path_element->class->verrno = EFAULT;
 521         return -1;
 522     }
 523
 524     len = strlen (ino->linkname);
 525     if (size < len)
 526         len = size;
 527     /* readlink() does not append a NUL character to buf */
 528     memcpy (buf, ino->linkname, len);
 529     return len;
 530 }
 531
 532 /* --------------------------------------------------------------------------------------------- */
 533
 534 static ssize_t
 535 vfs_s_read (void *fh, char *buffer, size_t count)
 536 {
 537     struct vfs_class *me = FH_SUPER->me;
 538
 539     if (FH->linear == LS_LINEAR_PREOPEN)
 540     {
 541         if (!MEDATA->linear_start (me, FH, FH->pos))
 542             return -1;
 543     }
 544
 545     if (FH->linear == LS_LINEAR_CLOSED)
 546         vfs_die ("linear_start() did not set linear_state!");
 547
 548     if (FH->linear == LS_LINEAR_OPEN)
 549         return MEDATA->linear_read (me, FH, buffer, count);
 550
 551     if (FH->handle != -1)
 552     {
 553         ssize_t n;
 554
 555         n = read (FH->handle, buffer, count);
 556         if (n < 0)
 557             me->verrno = errno;
 558         return n;
 559     }
 560     vfs_die ("vfs_s_read: This should not happen\n");
 561     return -1;
 562 }
 563
 564 /* --------------------------------------------------------------------------------------------- */
 565
 566 static ssize_t
 567 vfs_s_write (void *fh, const char *buffer, size_t count)
 568 {
 569     struct vfs_class *me = FH_SUPER->me;
 570
 571     if (FH->linear)
 572         vfs_die ("no writing to linear files, please");
 573
 574     FH->changed = 1;
 575     if (FH->handle != -1)
 576     {
 577         ssize_t n;
 578
 579         n = write (FH->handle, buffer, count);
 580         if (n < 0)
 581             me->verrno = errno;
 582         return n;
 583     }
 584     vfs_die ("vfs_s_write: This should not happen\n");
 585     return 0;
 586 }
 587
 588 /* --------------------------------------------------------------------------------------------- */
 589
 590 static off_t
 591 vfs_s_lseek (void *fh, off_t offset, int whence)
 592 {
 593     off_t size = FH->ino->st.st_size;
 594
 595     if (FH->linear == LS_LINEAR_OPEN)
 596         vfs_die ("cannot lseek() after linear_read!");
 597
 598     if (FH->handle != -1)
 599     {                           /* If we have local file opened, we want to work with it */
 600         off_t retval = lseek (FH->handle, offset, whence);
 601         if (retval == -1)
 602             FH->ino->super->me->verrno = errno;
 603         return retval;
 604     }
 605
 606     switch (whence)
 607     {
 608     case SEEK_CUR:
 609         offset += FH->pos;
 610         break;
 611     case SEEK_END:
 612         offset += size;
 613         break;
 614     default:
 615         break;
 616     }
 617     if (offset < 0)
 618         FH->pos = 0;
 619     else if (offset < size)
 620         FH->pos = offset;
 621     else
 622         FH->pos = size;
 623     return FH->pos;
 624 }
 625
 626 /* --------------------------------------------------------------------------------------------- */
 627
 628 static int
 629 vfs_s_close (void *fh)
 630 {
 631     int res = 0;
 632     struct vfs_class *me = FH_SUPER->me;
 633
 634     if (me == NULL)
 635         return (-1);
 636
 637     FH_SUPER->fd_usage--;
 638     if (!FH_SUPER->fd_usage)
 639         vfs_stamp_create (me, FH_SUPER);
 640
 641     if (FH->linear == LS_LINEAR_OPEN)
 642         MEDATA->linear_close (me, fh);
 643     if (MEDATA->fh_close)
 644         res = MEDATA->fh_close (me, fh);
 645     if ((MEDATA->flags & VFS_S_USETMP) && FH->changed && MEDATA->file_store)
 646     {
 647         char *s = vfs_s_fullpath (me, FH->ino);
 648         if (!s)
 649             res = -1;
 650         else
 651         {
 652             res = MEDATA->file_store (me, fh, s, FH->ino->localname);
 653             g_free (s);
 654         }
 655         vfs_s_invalidate (me, FH_SUPER);
 656     }
 657     if (FH->handle != -1)
 658         close (FH->handle);
 659
 660     vfs_s_free_inode (me, FH->ino);
 661     if (MEDATA->fh_free_data != NULL)
 662         MEDATA->fh_free_data (fh);
 663     g_free (fh);
 664     return res;
 665 }
 666
 667 /* --------------------------------------------------------------------------------------------- */
 668
 669 static void
 670 vfs_s_print_stats (const char *fs_name, const char *action,
 671                    const char *file_name, off_t have, off_t need)
 672 {
 673     if (need != 0)
 674         vfs_print_message (_("%s: %s: %s %3d%% (%lld) bytes transferred"), fs_name, action,
 675                            file_name, (int) ((double) have * 100 / need), (long long) have);
 676     else
 677         vfs_print_message (_("%s: %s: %s %lld bytes transferred"), fs_name, action, file_name,
 678                            (long long) have);
 679 }
 680
 681 /* --------------------------------------------------------------------------------------------- */
 682 /* ------------------------------- mc support ---------------------------- */
 683
 684 static void
 685 vfs_s_fill_names (struct vfs_class *me, fill_names_f func)
 686 {
 687     GList *iter;
 688
 689     for (iter = MEDATA->supers; iter != NULL; iter = g_list_next (iter))
 690     {
 691         const struct vfs_s_super *super = (const struct vfs_s_super *) iter->data;
 692         char *name;
 693
 694         name = g_strconcat (super->name, PATH_SEP_STR, me->prefix, VFS_PATH_URL_DELIMITER,
 695                             /* super->current_dir->name, */ (char *) NULL);
 696         func (name);
 697         g_free (name);
 698     }
 699 }
 700
 701 /* --------------------------------------------------------------------------------------------- */
 702
 703 static int
 704 vfs_s_ferrno (struct vfs_class *me)
 705 {
 706     return me->verrno;
 707 }
 708
 709 /* --------------------------------------------------------------------------------------------- */
 710 /**
 711  * Get local copy of the given file.  We reuse the existing file cache
 712  * for remote filesystems.  Archives use standard VFS facilities.
 713  */
 714
 715 static vfs_path_t *
 716 vfs_s_getlocalcopy (const vfs_path_t * vpath)
 717 {
 718     vfs_file_handler_t *fh;
 719     vfs_path_t *local = NULL;
 720
 721     if (vpath == NULL)
 722         return NULL;
 723
 724     fh = vfs_s_open (vpath, O_RDONLY, 0);
 725
 726     if (fh != NULL)
 727     {
 728         const struct vfs_class *me;
 729
 730         me = vfs_path_get_by_index (vpath, -1)->class;
 731         if ((MEDATA->flags & VFS_S_USETMP) != 0 && (fh->ino != NULL))
 732             local = vfs_path_from_str_flags (fh->ino->localname, VPF_NO_CANON);
 733
 734         vfs_s_close (fh);
 735     }
 736
 737     return local;
 738 }
 739
 740 /* --------------------------------------------------------------------------------------------- */
 741 /**
 742  * Return the local copy.  Since we are using our cache, we do nothing -
 743  * the cache will be removed when the archive is closed.
 744  */
 745
 746 static int
 747 vfs_s_ungetlocalcopy (const vfs_path_t * vpath, const vfs_path_t * local, gboolean has_changed)
 748 {
 749     (void) vpath;
 750     (void) local;
 751     (void) has_changed;
 752     return 0;
 753 }
 754
 755 /* --------------------------------------------------------------------------------------------- */
 756
 757 static int
 758 vfs_s_setctl (const vfs_path_t * vpath, int ctlop, void *arg)
 759 {
 760     const vfs_path_element_t *path_element;
 761
 762     path_element = vfs_path_get_by_index (vpath, -1);
 763
 764     switch (ctlop)
 765     {
 766     case VFS_SETCTL_STALE_DATA:
 767         {
 768             struct vfs_s_inode *ino;
 769
 770             ino = vfs_s_inode_from_path (vpath, 0);
 771             if (ino == NULL)
 772                 return 0;
 773             if (arg)
 774                 ino->super->want_stale = 1;
 775             else
 776             {
 777                 ino->super->want_stale = 0;
 778                 vfs_s_invalidate (path_element->class, ino->super);
 779             }
 780             return 1;
 781         }
 782     case VFS_SETCTL_LOGFILE:
 783         ((struct vfs_s_subclass *) path_element->class->data)->logfile = fopen ((char *) arg, "w");
 784         return 1;
 785     case VFS_SETCTL_FLUSH:
 786         ((struct vfs_s_subclass *) path_element->class->data)->flush = 1;
 787         return 1;
 788     default:
 789         return 0;
 790     }
 791 }
 792
 793 /* --------------------------------------------------------------------------------------------- */
 794 /* ----------------------------- Stamping support -------------------------- */
 795
 796 static vfsid
 797 vfs_s_getid (const vfs_path_t * vpath)
 798 {
 799     struct vfs_s_super *archive = NULL;
 800     const char *p;
 801
 802     p = vfs_s_get_path (vpath, &archive, FL_NO_OPEN);
 803     if (p == NULL)
 804         return NULL;
 805
 806     return (vfsid) archive;
 807 }
 808
 809 /* --------------------------------------------------------------------------------------------- */
 810
 811 static int
 812 vfs_s_nothingisopen (vfsid id)
 813 {
 814     (void) id;
 815     /* Our data structures should survive free of superblock at any time */
 816     return 1;
 817 }
 818
 819 /* --------------------------------------------------------------------------------------------- */
 820
 821 static void
 822 vfs_s_free (vfsid id)
 823 {
 824     vfs_s_free_super (((struct vfs_s_super *) id)->me, (struct vfs_s_super *) id);
 825 }
 826
 827 /* --------------------------------------------------------------------------------------------- */
 828
 829 static int
 830 vfs_s_dir_uptodate (struct vfs_class *me, struct vfs_s_inode *ino)
 831 {
 832     struct timeval tim;
 833
 834     if (MEDATA->flush)
 835     {
 836         MEDATA->flush = 0;
 837         return 0;
 838     }
 839
 840     gettimeofday (&tim, NULL);
 841     if (tim.tv_sec < ino->timestamp.tv_sec)
 842         return 1;
 843     return 0;
 844 }
 845
 846
 847 /* --------------------------------------------------------------------------------------------- */
 848 /*** public functions ****************************************************************************/
 849 /* --------------------------------------------------------------------------------------------- */
 850
 851 struct vfs_s_inode *
 852 vfs_s_new_inode (struct vfs_class *me, struct vfs_s_super *super, struct stat *initstat)
 853 {
 854     struct vfs_s_inode *ino;
 855
 856     ino = g_try_new0 (struct vfs_s_inode, 1);
 857     if (ino == NULL)
 858         return NULL;
 859
 860     if (initstat)
 861         ino->st = *initstat;
 862     ino->super = super;
 863     ino->st.st_nlink = 0;
 864     ino->st.st_ino = MEDATA->inode_counter++;
 865     ino->st.st_dev = MEDATA->rdev;
 866
 867     super->ino_usage++;
 868
 869     CALL (init_inode) (me, ino);
 870
 871     return ino;
 872 }
 873
 874 /* --------------------------------------------------------------------------------------------- */
 875
 876 void
 877 vfs_s_free_inode (struct vfs_class *me, struct vfs_s_inode *ino)
 878 {
 879     if (ino == NULL)
 880         vfs_die ("Don't pass NULL to me");
 881
 882     /* ==0 can happen if freshly created entry is deleted */
 883     if (ino->st.st_nlink > 1)
 884     {
 885         ino->st.st_nlink--;
 886         return;
 887     }
 888
 889     while (ino->subdir != NULL)
 890         vfs_s_free_entry (me, (struct vfs_s_entry *) ino->subdir->data);
 891
 892     CALL (free_inode) (me, ino);
 893     g_free (ino->linkname);
 894     if ((MEDATA->flags & VFS_S_USETMP) != 0 && ino->localname != NULL)
 895     {
 896         unlink (ino->localname);
 897         g_free (ino->localname);
 898     }
 899     ino->super->ino_usage--;
 900     g_free (ino);
 901 }
 902
 903 /* --------------------------------------------------------------------------------------------- */
 904
 905 struct vfs_s_entry *
 906 vfs_s_new_entry (struct vfs_class *me, const char *name, struct vfs_s_inode *inode)
 907 {
 908     struct vfs_s_entry *entry;
 909
 910     entry = g_new0 (struct vfs_s_entry, 1);
 911
 912     entry->name = g_strdup (name);
 913     entry->ino = inode;
 914     entry->ino->ent = entry;
 915     CALL (init_entry) (me, entry);
 916
 917     return entry;
 918 }
 919
 920
 921 /* --------------------------------------------------------------------------------------------- */
 922
 923 void
 924 vfs_s_free_entry (struct vfs_class *me, struct vfs_s_entry *ent)
 925 {
 926     if (ent->dir != NULL)
 927         ent->dir->subdir = g_list_remove (ent->dir->subdir, ent);
 928
 929     MC_PTR_FREE (ent->name);
 930
 931     if (ent->ino != NULL)
 932     {
 933         ent->ino->ent = NULL;
 934         vfs_s_free_inode (me, ent->ino);
 935     }
 936
 937     g_free (ent);
 938 }
 939
 940 /* --------------------------------------------------------------------------------------------- */
 941
 942 void
 943 vfs_s_insert_entry (struct vfs_class *me, struct vfs_s_inode *dir, struct vfs_s_entry *ent)
 944 {
 945     (void) me;
 946
 947     ent->dir = dir;
 948
 949     ent->ino->st.st_nlink++;
 950     dir->subdir = g_list_append (dir->subdir, ent);
 951 }
 952
 953 /* --------------------------------------------------------------------------------------------- */
 954
 955 struct stat *
 956 vfs_s_default_stat (struct vfs_class *me, mode_t mode)
 957 {
 958     static struct stat st;
 959     mode_t myumask;
 960
 961     (void) me;
 962
 963     myumask = umask (022);
 964     umask (myumask);
 965     mode &= ~myumask;
 966
 967     st.st_mode = mode;
 968     st.st_ino = 0;
 969     st.st_dev = 0;
 970 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 971     st.st_rdev = 0;
 972 #endif
 973     st.st_uid = getuid ();
 974     st.st_gid = getgid ();
 975 #ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
 976     st.st_blksize = 512;
 977 #endif
 978     st.st_size = 0;
 979
 980     st.st_mtime = st.st_atime = st.st_ctime = time (NULL);
 981 #ifdef HAVE_STRUCT_STAT_ST_MTIM
 982     st.st_atim.tv_nsec = st.st_mtim.tv_nsec = st.st_ctim.tv_nsec = 0;
 983 #endif
 984
 985     vfs_adjust_stat (&st);
 986
 987     return &st;
 988 }
 989
 990 /* --------------------------------------------------------------------------------------------- */
 991 /**
 992  * Calculate number of st_blocks using st_size and st_blksize.
 993  * In according to stat(2), st_blocks is the size in 512-byte units.
 994  *
 995  * @param s stat info
 996  */
 997
 998 void
 999 vfs_adjust_stat (struct stat *s)
1000 {
1001 #ifdef HAVE_STRUCT_STAT_ST_BLOCKS
1002     if (s->st_size == 0)
1003         s->st_blocks = 0;
1004     else
1005     {
1006 #ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
1007         blkcnt_t ioblocks;
1008         blksize_t ioblock_size;
1009
1010         /* 1. Calculate how many IO blocks are occupied */
1011         ioblocks = 1 + (s->st_size - 1) / s->st_blksize;
1012         /* 2. Calculate size of st_blksize in 512-byte units */
1013         ioblock_size = 1 + (s->st_blksize - 1) / 512;
1014         /* 3. Calculate number of blocks */
1015         s->st_blocks = ioblocks * ioblock_size;
1016 #else
1017         /* Let IO block size is 512 bytes */
1018         s->st_blocks = 1 + (s->st_size - 1) / 512;
1019 #endif /* HAVE_STRUCT_STAT_ST_BLKSIZE */
1020     }
1021 #endif /* HAVE_STRUCT_STAT_ST_BLOCKS */
1022 }
1023
1024 /* --------------------------------------------------------------------------------------------- */
1025
1026 struct vfs_s_entry *
1027 vfs_s_generate_entry (struct vfs_class *me, const char *name, struct vfs_s_inode *parent,
1028                       mode_t mode)
1029 {
1030     struct vfs_s_inode *inode;
1031     struct stat *st;
1032
1033     st = vfs_s_default_stat (me, mode);
1034     inode = vfs_s_new_inode (me, parent->super, st);
1035
1036     return vfs_s_new_entry (me, name, inode);
1037 }
1038
1039 /* --------------------------------------------------------------------------------------------- */
1040
1041 struct vfs_s_inode *
1042 vfs_s_find_inode (struct vfs_class *me, const struct vfs_s_super *super,
1043                   const char *path, int follow, int flags)
1044 {
1045     struct vfs_s_entry *ent;
1046
1047     if (((MEDATA->flags & VFS_S_REMOTE) == 0) && (*path == '\0'))
1048         return super->root;
1049
1050     ent = (MEDATA->find_entry) (me, super->root, path, follow, flags);
1051     return (ent != NULL) ? ent->ino : NULL;
1052 }
1053
1054 /* --------------------------------------------------------------------------------------------- */
1055 /* Ook, these were functions around directory entries / inodes */
1056 /* -------------------------------- superblock games -------------------------- */
1057 /**
1058  * get superlock object by vpath
1059  *
1060  * @param vpath path
1061  * @return superlock object or NULL if not found
1062  */
1063
1064 struct vfs_s_super *
1065 vfs_get_super_by_vpath (const vfs_path_t * vpath)
1066 {
1067     GList *iter;
1068     void *cookie = NULL;
1069     const vfs_path_element_t *path_element;
1070     struct vfs_s_subclass *subclass;
1071     struct vfs_s_super *super = NULL;
1072     vfs_path_t *vpath_archive;
1073
1074     path_element = vfs_path_get_by_index (vpath, -1);
1075     subclass = ((struct vfs_s_subclass *) path_element->class->data);
1076     if (subclass == NULL)
1077         return NULL;
1078
1079     vpath_archive = vfs_path_clone (vpath);
1080     vfs_path_remove_element_by_index (vpath_archive, -1);
1081
1082     if (subclass->archive_check != NULL)
1083     {
1084         cookie = subclass->archive_check (vpath_archive);
1085         if (cookie == NULL)
1086             goto ret;
1087     }
1088
1089     for (iter = subclass->supers; iter != NULL; iter = g_list_next (iter))
1090     {
1091         int i;
1092
1093         super = (struct vfs_s_super *) iter->data;
1094
1095         /* 0 == other, 1 == same, return it, 2 == other but stop scanning */
1096         i = subclass->archive_same (path_element, super, vpath_archive, cookie);
1097         if (i == 1)
1098             goto ret;
1099         if (i != 0)
1100             break;
1101
1102         super = NULL;
1103     }
1104
1105   ret:
1106     vfs_path_free (vpath_archive);
1107     return super;
1108 }
1109
1110 /* --------------------------------------------------------------------------------------------- */
1111 /**
1112  * get path from last VFS-element and create corresponding superblock
1113  *
1114  * @param vpath source path object
1115  * @param archive pointer to object for store newly created superblock
1116  * @param flags flags
1117  *
1118  * @return path from last VFS-element
1119  */
1120 const char *
1121 vfs_s_get_path (const vfs_path_t * vpath, struct vfs_s_super **archive, int flags)
1122 {
1123     const char *retval = "";
1124     int result = -1;
1125     struct vfs_s_super *super;
1126     const vfs_path_element_t *path_element;
1127     struct vfs_s_subclass *subclass;
1128
1129     path_element = vfs_path_get_by_index (vpath, -1);
1130
1131     if (path_element->path != NULL)
1132         retval = path_element->path;
1133
1134     super = vfs_get_super_by_vpath (vpath);
1135     if (super != NULL)
1136         goto return_success;
1137
1138     if (flags & FL_NO_OPEN)
1139     {
1140         path_element->class->verrno = EIO;
1141         return NULL;
1142     }
1143
1144     super = vfs_s_new_super (path_element->class);
1145
1146     subclass = ((struct vfs_s_subclass *) path_element->class->data);
1147     if (subclass->open_archive != NULL)
1148     {
1149         vfs_path_t *vpath_archive;
1150
1151         vpath_archive = vfs_path_clone (vpath);
1152         vfs_path_remove_element_by_index (vpath_archive, -1);
1153
1154         result = subclass->open_archive (super, vpath_archive, path_element);
1155         vfs_path_free (vpath_archive);
1156     }
1157     if (result == -1)
1158     {
1159         vfs_s_free_super (path_element->class, super);
1160         path_element->class->verrno = EIO;
1161         return NULL;
1162     }
1163     if (!super->name)
1164         vfs_die ("You have to fill name\n");
1165     if (!super->root)
1166         vfs_die ("You have to fill root inode\n");
1167
1168     vfs_s_insert_super (path_element->class, super);
1169     vfs_stamp_create (path_element->class, super);
1170
1171   return_success:
1172     *archive = super;
1173     return retval;
1174 }
1175
1176 /* --------------------------------------------------------------------------------------------- */
1177
1178 void
1179 vfs_s_invalidate (struct vfs_class *me, struct vfs_s_super *super)
1180 {
1181     if (!super->want_stale)
1182     {
1183         vfs_s_free_inode (me, super->root);
1184         super->root = vfs_s_new_inode (me, super, vfs_s_default_stat (me, S_IFDIR | 0755));
1185     }
1186 }
1187
1188 /* --------------------------------------------------------------------------------------------- */
1189
1190 char *
1191 vfs_s_fullpath (struct vfs_class *me, struct vfs_s_inode *ino)
1192 {
1193     if (!ino->ent)
1194         ERRNOR (EAGAIN, NULL);
1195
1196     if ((MEDATA->flags & VFS_S_USETMP) == 0)
1197     {
1198         /* archives */
1199         char *newpath;
1200         char *path = g_strdup (ino->ent->name);
1201         while (1)
1202         {
1203             ino = ino->ent->dir;
1204             if (ino == ino->super->root)
1205                 break;
1206             newpath = g_strconcat (ino->ent->name, PATH_SEP_STR, path, (char *) NULL);
1207             g_free (path);
1208             path = newpath;
1209         }
1210         return path;
1211     }
1212
1213     /* remote systems */
1214     if ((!ino->ent->dir) || (!ino->ent->dir->ent))
1215         return g_strdup (ino->ent->name);
1216
1217     return g_strconcat (ino->ent->dir->ent->name, PATH_SEP_STR, ino->ent->name, (char *) NULL);
1218 }
1219
1220 /* --------------------------------------------------------------------------------------------- */
1221 /* --------------------------- stat and friends ---------------------------- */
1222
1223 void *
1224 vfs_s_open (const vfs_path_t * vpath, int flags, mode_t mode)
1225 {
1226     int was_changed = 0;
1227     vfs_file_handler_t *fh;
1228     struct vfs_s_super *super;
1229     const char *q;
1230     struct vfs_s_inode *ino;
1231     const vfs_path_element_t *path_element;
1232
1233     path_element = vfs_path_get_by_index (vpath, -1);
1234
1235     q = vfs_s_get_path (vpath, &super, 0);
1236     if (q == NULL)
1237         return NULL;
1238     ino = vfs_s_find_inode (path_element->class, super, q, LINK_FOLLOW, FL_NONE);
1239     if (ino && ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)))
1240     {
1241         path_element->class->verrno = EEXIST;
1242         return NULL;
1243     }
1244     if (!ino)
1245     {
1246         char *dirname, *name;
1247         struct vfs_s_entry *ent;
1248         struct vfs_s_inode *dir;
1249
1250         /* If the filesystem is read-only, disable file creation */
1251         if (!(flags & O_CREAT) || !(path_element->class->write))
1252             return NULL;
1253
1254         dirname = g_path_get_dirname (q);
1255         name = g_path_get_basename (q);
1256         dir = vfs_s_find_inode (path_element->class, super, dirname, LINK_FOLLOW, FL_DIR);
1257         if (dir == NULL)
1258         {
1259             g_free (dirname);
1260             g_free (name);
1261             return NULL;
1262         }
1263         ent = vfs_s_generate_entry (path_element->class, name, dir, 0755);
1264         ino = ent->ino;
1265         vfs_s_insert_entry (path_element->class, dir, ent);
1266         if ((VFSDATA (path_element)->flags & VFS_S_USETMP) != 0)
1267         {
1268             int tmp_handle;
1269             vfs_path_t *tmp_vpath;
1270
1271             tmp_handle = vfs_mkstemps (&tmp_vpath, path_element->class->name, name);
1272             ino->localname = g_strdup (vfs_path_as_str (tmp_vpath));
1273             vfs_path_free (tmp_vpath);
1274             if (tmp_handle == -1)
1275             {
1276                 g_free (dirname);
1277                 g_free (name);
1278                 return NULL;
1279             }
1280
1281             close (tmp_handle);
1282         }
1283         g_free (dirname);
1284         g_free (name);
1285         was_changed = 1;
1286     }
1287
1288     if (S_ISDIR (ino->st.st_mode))
1289     {
1290         path_element->class->verrno = EISDIR;
1291         return NULL;
1292     }
1293
1294     fh = g_new (vfs_file_handler_t, 1);
1295     fh->pos = 0;
1296     fh->ino = ino;
1297     fh->handle = -1;
1298     fh->changed = was_changed;
1299     fh->linear = 0;
1300     fh->data = NULL;
1301
1302     if (IS_LINEAR (flags))
1303     {
1304         if (VFSDATA (path_element)->linear_start)
1305         {
1306             vfs_print_message ("%s", _("Starting linear transfer..."));
1307             fh->linear = LS_LINEAR_PREOPEN;
1308         }
1309     }
1310     else
1311     {
1312         struct vfs_s_subclass *s;
1313
1314         s = VFSDATA (path_element);
1315         if (s->fh_open != NULL && s->fh_open (path_element->class, fh, flags, mode) != 0)
1316         {
1317             if (s->fh_free_data != NULL)
1318                 s->fh_free_data (fh);
1319             g_free (fh);
1320             return NULL;
1321         }
1322     }
1323
1324     if ((VFSDATA (path_element)->flags & VFS_S_USETMP) != 0 && fh->ino->localname != NULL)
1325     {
1326         fh->handle = open (fh->ino->localname, NO_LINEAR (flags), mode);
1327         if (fh->handle == -1)
1328         {
1329             g_free (fh);
1330             path_element->class->verrno = errno;
1331             return NULL;
1332         }
1333     }
1334
1335     /* i.e. we had no open files and now we have one */
1336     vfs_rmstamp (path_element->class, (vfsid) super);
1337     super->fd_usage++;
1338     fh->ino->st.st_nlink++;
1339     return fh;
1340 }
1341
1342 /* --------------------------------------------------------------------------------------------- */
1343
1344 int
1345 vfs_s_stat (const vfs_path_t * vpath, struct stat *buf)
1346 {
1347     return vfs_s_internal_stat (vpath, buf, FL_FOLLOW);
1348 }
1349
1350 /* --------------------------------------------------------------------------------------------- */
1351
1352 int
1353 vfs_s_lstat (const vfs_path_t * vpath, struct stat *buf)
1354 {
1355     return vfs_s_internal_stat (vpath, buf, FL_NONE);
1356 }
1357
1358 /* --------------------------------------------------------------------------------------------- */
1359
1360 int
1361 vfs_s_fstat (void *fh, struct stat *buf)
1362 {
1363     *buf = FH->ino->st;
1364     return 0;
1365 }
1366
1367 /* --------------------------------------------------------------------------------------------- */
1368
1369 int
1370 vfs_s_retrieve_file (struct vfs_class *me, struct vfs_s_inode *ino)
1371 {
1372     /* If you want reget, you'll have to open file with O_LINEAR */
1373     off_t total = 0;
1374     char buffer[8192];
1375     int handle;
1376     ssize_t n;
1377     off_t stat_size = ino->st.st_size;
1378     vfs_file_handler_t fh;
1379     vfs_path_t *tmp_vpath;
1380
1381     if ((MEDATA->flags & VFS_S_USETMP) == 0)
1382         return -1;
1383
1384     memset (&fh, 0, sizeof (fh));
1385
1386     fh.ino = ino;
1387     fh.handle = -1;
1388
1389     handle = vfs_mkstemps (&tmp_vpath, me->name, ino->ent->name);
1390     ino->localname = g_strdup (vfs_path_as_str (tmp_vpath));
1391     vfs_path_free (tmp_vpath);
1392     if (handle == -1)
1393     {
1394         me->verrno = errno;
1395         goto error_4;
1396     }
1397
1398     if (!MEDATA->linear_start (me, &fh, 0))
1399         goto error_3;
1400
1401     /* Clear the interrupt status */
1402     tty_got_interrupt ();
1403     tty_enable_interrupt_key ();
1404
1405     while ((n = MEDATA->linear_read (me, &fh, buffer, sizeof (buffer))))
1406     {
1407         int t;
1408         if (n < 0)
1409             goto error_1;
1410
1411         total += n;
1412         vfs_s_print_stats (me->name, _("Getting file"), ino->ent->name, total, stat_size);
1413
1414         if (tty_got_interrupt ())
1415             goto error_1;
1416
1417         t = write (handle, buffer, n);
1418         if (t != n)
1419         {
1420             if (t == -1)
1421                 me->verrno = errno;
1422             goto error_1;
1423         }
1424     }
1425     MEDATA->linear_close (me, &fh);
1426     close (handle);
1427
1428     tty_disable_interrupt_key ();
1429     g_free (fh.data);
1430     return 0;
1431
1432   error_1:
1433     MEDATA->linear_close (me, &fh);
1434   error_3:
1435     tty_disable_interrupt_key ();
1436     close (handle);
1437     unlink (ino->localname);
1438   error_4:
1439     MC_PTR_FREE (ino->localname);
1440     g_free (fh.data);
1441     return -1;
1442 }
1443
1444 /* --------------------------------------------------------------------------------------------- */
1445 /* ----------------------------- Stamping support -------------------------- */
1446
1447 /* Initialize one of our subclasses - fill common functions */
1448 void
1449 vfs_s_init_class (struct vfs_class *vclass, struct vfs_s_subclass *sub)
1450 {
1451     vclass->data = sub;
1452     vclass->fill_names = vfs_s_fill_names;
1453     vclass->open = vfs_s_open;
1454     vclass->close = vfs_s_close;
1455     vclass->read = vfs_s_read;
1456     if (!(sub->flags & VFS_S_READONLY))
1457     {
1458         vclass->write = vfs_s_write;
1459     }
1460     vclass->opendir = vfs_s_opendir;
1461     vclass->readdir = vfs_s_readdir;
1462     vclass->closedir = vfs_s_closedir;
1463     vclass->stat = vfs_s_stat;
1464     vclass->lstat = vfs_s_lstat;
1465     vclass->fstat = vfs_s_fstat;
1466     vclass->readlink = vfs_s_readlink;
1467     vclass->chdir = vfs_s_chdir;
1468     vclass->ferrno = vfs_s_ferrno;
1469     vclass->lseek = vfs_s_lseek;
1470     vclass->getid = vfs_s_getid;
1471     vclass->nothingisopen = vfs_s_nothingisopen;
1472     vclass->free = vfs_s_free;
1473     if ((sub->flags & VFS_S_USETMP) != 0)
1474     {
1475         vclass->getlocalcopy = vfs_s_getlocalcopy;
1476         vclass->ungetlocalcopy = vfs_s_ungetlocalcopy;
1477         sub->find_entry = vfs_s_find_entry_linear;
1478     }
1479     else if ((sub->flags & VFS_S_REMOTE) != 0)
1480         sub->find_entry = vfs_s_find_entry_linear;
1481     else
1482         sub->find_entry = vfs_s_find_entry_tree;
1483     vclass->setctl = vfs_s_setctl;
1484     sub->dir_uptodate = vfs_s_dir_uptodate;
1485 }
1486
1487 /* --------------------------------------------------------------------------------------------- */
1488 /** Find VFS id for given directory name */
1489
1490 vfsid
1491 vfs_getid (const vfs_path_t * vpath)
1492 {
1493     const vfs_path_element_t *path_element;
1494
1495     path_element = vfs_path_get_by_index (vpath, -1);
1496     if (!vfs_path_element_valid (path_element) || path_element->class->getid == NULL)
1497         return NULL;
1498
1499     return (*path_element->class->getid) (vpath);
1500 }
1501
1502 /* --------------------------------------------------------------------------------------------- */
1503 /* ----------- Utility functions for networked filesystems  -------------- */
1504
1505 #ifdef ENABLE_VFS_NET
1506 int
1507 vfs_s_select_on_two (int fd1, int fd2)
1508 {
1509     fd_set set;
1510     struct timeval time_out;
1511     int v;
1512     int maxfd = (fd1 > fd2 ? fd1 : fd2) + 1;
1513
1514     time_out.tv_sec = 1;
1515     time_out.tv_usec = 0;
1516     FD_ZERO (&set);
1517     FD_SET (fd1, &set);
1518     FD_SET (fd2, &set);
1519     v = select (maxfd, &set, 0, 0, &time_out);
1520     if (v <= 0)
1521         return v;
1522     if (FD_ISSET (fd1, &set))
1523         return 1;
1524     if (FD_ISSET (fd2, &set))
1525         return 2;
1526     return -1;
1527 }
1528
1529 /* --------------------------------------------------------------------------------------------- */
1530
1531 int
1532 vfs_s_get_line (struct vfs_class *me, int sock, char *buf, int buf_len, char term)
1533 {
1534     FILE *logfile = MEDATA->logfile;
1535     int i;
1536     char c;
1537
1538     for (i = 0; i < buf_len - 1; i++, buf++)
1539     {
1540         if (read (sock, buf, sizeof (char)) <= 0)
1541             return 0;
1542         if (logfile)
1543         {
1544             size_t ret1;
1545             int ret2;
1546             ret1 = fwrite (buf, 1, 1, logfile);
1547             ret2 = fflush (logfile);
1548             (void) ret1;
1549             (void) ret2;
1550         }
1551         if (*buf == term)
1552         {
1553             *buf = 0;
1554             return 1;
1555         }
1556     }
1557
1558     /* Line is too long - terminate buffer and discard the rest of line */
1559     *buf = 0;
1560     while (read (sock, &c, sizeof (c)) > 0)
1561     {
1562         if (logfile)
1563         {
1564             size_t ret1;
1565             int ret2;
1566             ret1 = fwrite (&c, 1, 1, logfile);
1567             ret2 = fflush (logfile);
1568             (void) ret1;
1569             (void) ret2;
1570         }
1571         if (c == '\n')
1572             return 1;
1573     }
1574     return 0;
1575 }
1576
1577 /* --------------------------------------------------------------------------------------------- */
1578
1579 int
1580 vfs_s_get_line_interruptible (struct vfs_class *me, char *buffer, int size, int fd)
1581 {
1582     int i;
1583     int res = 0;
1584
1585     (void) me;
1586
1587     tty_enable_interrupt_key ();
1588
1589     for (i = 0; i < size - 1; i++)
1590     {
1591         ssize_t n;
1592
1593         n = read (fd, &buffer[i], 1);
1594         if (n == -1 && errno == EINTR)
1595         {
1596             buffer[i] = '\0';
1597             res = EINTR;
1598             goto ret;
1599         }
1600         if (n == 0)
1601         {
1602             buffer[i] = '\0';
1603             goto ret;
1604         }
1605         if (buffer[i] == '\n')
1606         {
1607             buffer[i] = '\0';
1608             res = 1;
1609             goto ret;
1610         }
1611     }
1612
1613     buffer[size - 1] = '\0';
1614
1615   ret:
1616     tty_disable_interrupt_key ();
1617
1618     return res;
1619 }
1620 #endif /* ENABLE_VFS_NET */
1621
1622 /* --------------------------------------------------------------------------------------------- */
1623 /**
1624  * Normalize filenames start position
1625  */
1626
1627 void
1628 vfs_s_normalize_filename_leading_spaces (struct vfs_s_inode *root_inode, size_t final_num_spaces)
1629 {
1630     GList *iter;
1631
1632     for (iter = root_inode->subdir; iter != NULL; iter = g_list_next (iter))
1633     {
1634         struct vfs_s_entry *entry = (struct vfs_s_entry *) iter->data;
1635         if ((size_t) entry->ino->data_offset > final_num_spaces)
1636         {
1637             char *source_name = entry->name;
1638             char *spacer = g_strnfill (entry->ino->data_offset - final_num_spaces, ' ');
1639             entry->name = g_strdup_printf ("%s%s", spacer, source_name);
1640             g_free (spacer);
1641             g_free (source_name);
1642         }
1643         entry->ino->data_offset = -1;
1644     }
1645 }
1646
1647 /* --------------------------------------------------------------------------------------------- */