vfs/vfs.c

   1 /* Virtual File System switch code
   2    Copyright (C) 1995, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
   3    2007 Free Software Foundation, Inc.
   4
   5    Written by: 1995 Miguel de Icaza
   6                1995 Jakub Jelinek
   7                1998 Pavel Machek
   8
   9    This program is free software; you can redistribute it and/or
  10    modify it under the terms of the GNU Library General Public License
  11    as published by the Free Software Foundation; either version 2 of
  12    the License, or (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU Library General Public License for more details.
  18
  19    You should have received a copy of the GNU Library General Public
  20    License along with this program; if not, write to the Free Software
  21    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  22
  23 /**
  24  * \file
  25  * \brief Source: Virtual File System switch code
  26  * \author Miguel de Icaza
  27  * \author Jakub Jelinek
  28  * \author Pavel Machek
  29  * \date 1995, 1998
  30  * \warning funtions like extfs_lstat() have right to destroy any
  31  * strings you pass to them. This is acutally ok as you g_strdup what
  32  * you are passing to them, anyway; still, beware.
  33  *
  34  * Namespace: exports *many* functions with vfs_ prefix; exports
  35  * parse_ls_lga and friends which do not have that prefix.
  36  */
  37
  38 #include <config.h>
  39
  40 #include <stdio.h>
  41 #include <stdlib.h>             /* For atol() */
  42 #include <stdarg.h>
  43 #include <string.h>
  44 #include <errno.h>
  45 #include <sys/types.h>
  46 #include <signal.h>
  47 #include <ctype.h>      /* is_digit() */
  48 #include <fcntl.h>
  49 #include <sys/stat.h>
  50 #include <unistd.h>
  51 #include <dirent.h>
  52
  53 #include "../src/global.h"
  54
  55 #include "../src/wtools.h"      /* message() */
  56 #include "../src/main.h"        /* print_vfs_message */
  57 #include "../src/strutil.h"
  58
  59 #include "utilvfs.h"
  60 #include "gc.h"
  61 #include "vfs.h"
  62 #ifdef USE_NETCODE
  63 #   include "tcputil.h"
  64 #endif
  65 #include "ftpfs.h"
  66 #include "mcfs.h"
  67 #include "smbfs.h"
  68 #include "local.h"
  69
  70 /** They keep track of the current directory */
  71 static struct vfs_class *current_vfs;
  72 static char *current_dir;
  73
  74 struct vfs_openfile {
  75     int handle;
  76     struct vfs_class *vclass;
  77     void *fsinfo;
  78 };
  79
  80 struct vfs_dirinfo{
  81     DIR *info;
  82     GIConv converter;
  83 };
  84
  85
  86 static GPtrArray *vfs_openfiles;
  87 static long vfs_free_handle_list = -1;
  88 #define VFS_FIRST_HANDLE 100
  89
  90 static struct vfs_class *localfs_class;
  91 static GString *vfs_str_buffer;
  92
  93 static const char *supported_encodings[] = {
  94     "UTF8",
  95     "UTF-8",
  96     "BIG5",
  97     "ASCII",
  98     "ISO8859",
  99     "ISO-8859",
 100     "ISO_8859",
 101     "KOI8",
 102     "CP852",
 103     "CP866",
 104     "CP125",
 105     NULL
 106 };
 107
 108 /** Create new VFS handle and put it to the list */
 109 static int
 110 vfs_new_handle (struct vfs_class *vclass, void *fsinfo)
 111 {
 112     struct vfs_openfile *h;
 113
 114     h = g_new (struct vfs_openfile, 1);
 115     h->fsinfo = fsinfo;
 116     h->vclass = vclass;
 117
 118     /* Allocate the first free handle */
 119     h->handle = vfs_free_handle_list;
 120     if (h->handle == -1) {
 121         /* No free allocated handles, allocate one */
 122         h->handle = vfs_openfiles->len;
 123         g_ptr_array_add (vfs_openfiles, h);
 124     } else {
 125         vfs_free_handle_list = (long) g_ptr_array_index (vfs_openfiles, vfs_free_handle_list);
 126         g_ptr_array_index (vfs_openfiles, h->handle) = h;
 127     }
 128
 129     h->handle += VFS_FIRST_HANDLE;
 130     return h->handle;
 131 }
 132
 133 /** Find VFS class by file handle */
 134 static inline struct vfs_class *
 135 vfs_op (int handle)
 136 {
 137     struct vfs_openfile *h;
 138
 139     if (handle < VFS_FIRST_HANDLE ||
 140         (guint)(handle - VFS_FIRST_HANDLE) >= vfs_openfiles->len)
 141         return NULL;
 142
 143     h = (struct vfs_openfile *) g_ptr_array_index (
 144                                 vfs_openfiles, handle - VFS_FIRST_HANDLE);
 145     if (!h)
 146         return NULL;
 147
 148     g_assert (h->handle == handle);
 149
 150     return h->vclass;
 151 }
 152
 153 /** Find private file data by file handle */
 154 static inline void *
 155 vfs_info (int handle)
 156 {
 157     struct vfs_openfile *h;
 158
 159     if (handle < VFS_FIRST_HANDLE ||
 160         (guint)(handle - VFS_FIRST_HANDLE) >= vfs_openfiles->len)
 161         return NULL;
 162
 163     h = (struct vfs_openfile *) g_ptr_array_index (
 164                                 vfs_openfiles, handle - VFS_FIRST_HANDLE);
 165     if (!h)
 166         return NULL;
 167
 168     g_assert (h->handle == handle);
 169
 170     return h->fsinfo;
 171 }
 172
 173 /** Free open file data for given file handle */
 174 static inline void
 175 vfs_free_handle (int handle)
 176 {
 177     if (handle < VFS_FIRST_HANDLE ||
 178         (guint)(handle - VFS_FIRST_HANDLE) >= vfs_openfiles->len)
 179         return;
 180
 181     g_ptr_array_index (vfs_openfiles, handle - VFS_FIRST_HANDLE) =
 182                         (void *) vfs_free_handle_list;
 183     vfs_free_handle_list = handle - VFS_FIRST_HANDLE;
 184 }
 185
 186 static struct vfs_class *vfs_list;
 187
 188 int
 189 vfs_register_class (struct vfs_class *vfs)
 190 {
 191     if (vfs->init)              /* vfs has own initialization function */
 192         if (!(*vfs->init)(vfs)) /* but it failed */
 193             return 0;
 194
 195     vfs->next = vfs_list;
 196     vfs_list = vfs;
 197
 198     return 1;
 199 }
 200
 201 /** Return VFS class for the given prefix */
 202 static struct vfs_class *
 203 vfs_prefix_to_class (char *prefix)
 204 {
 205     struct vfs_class *vfs;
 206
 207     /* Avoid last class (localfs) that would accept any prefix */
 208     for (vfs = vfs_list; vfs->next; vfs = vfs->next) {
 209         if (vfs->which) {
 210             if ((*vfs->which) (vfs, prefix) == -1)
 211                 continue;
 212             return vfs;
 213         }
 214         if (vfs->prefix
 215             && !strncmp (prefix, vfs->prefix, strlen (vfs->prefix)))
 216             return vfs;
 217     }
 218     return NULL;
 219 }
 220
 221 /** Strip known vfs suffixes from a filename (possible improvement: strip
 222  *  suffix from last path component).
 223  *  \return a malloced string which has to be freed.
 224  */
 225 char *
 226 vfs_strip_suffix_from_filename (const char *filename)
 227 {
 228     struct vfs_class *vfs;
 229     char *semi;
 230     char *p;
 231
 232     if (!filename)
 233         vfs_die ("vfs_strip_suffix_from_path got NULL: impossible");
 234
 235     p = g_strdup (filename);
 236     if (!(semi = strrchr (p, '#')))
 237         return p;
 238
 239     /* Avoid last class (localfs) that would accept any prefix */
 240     for (vfs = vfs_list; vfs->next; vfs = vfs->next) {
 241         if (vfs->which) {
 242             if ((*vfs->which) (vfs, semi + 1) == -1)
 243                 continue;
 244             *semi = '\0';       /* Found valid suffix */
 245             return p;
 246         }
 247         if (vfs->prefix
 248             && !strncmp (semi + 1, vfs->prefix, strlen (vfs->prefix))) {
 249             *semi = '\0';       /* Found valid suffix */
 250             return p;
 251         }
 252     }
 253     return p;
 254 }
 255
 256 static inline int
 257 path_magic (const char *path)
 258 {
 259     struct stat buf;
 260
 261     if (!stat(path, &buf))
 262         return 0;
 263
 264     return 1;
 265 }
 266
 267 /**
 268  * Splits path '/p1#op/inpath' into inpath,op; returns which vfs it is.
 269  * What is left in path is p1. You still want to g_free(path), you DON'T
 270  * want to free neither *inpath nor *op
 271  */
 272 struct vfs_class *
 273 vfs_split (char *path, char **inpath, char **op)
 274 {
 275     char *semi;
 276     char *slash;
 277     struct vfs_class *ret;
 278
 279     if (!path)
 280         vfs_die("Cannot split NULL");
 281
 282     semi = strrchr (path, '#');
 283     if (!semi || !path_magic(path))
 284         return NULL;
 285
 286     slash = strchr (semi, PATH_SEP);
 287     *semi = 0;
 288
 289     if (op)
 290         *op = NULL;
 291
 292     if (inpath)
 293         *inpath = NULL;
 294
 295     if (slash)
 296         *slash = 0;
 297
 298     if ((ret = vfs_prefix_to_class (semi+1))){
 299         if (op)
 300             *op = semi + 1;
 301         if (inpath)
 302             *inpath = slash ? slash + 1 : NULL;
 303         return ret;
 304     }
 305
 306
 307     if (slash)
 308         *slash = PATH_SEP;
 309     ret = vfs_split (path, inpath, op);
 310     *semi = '#';
 311     return ret;
 312 }
 313
 314 static struct vfs_class *
 315 _vfs_get_class (char *path)
 316 {
 317     char *semi;
 318     char *slash;
 319     struct vfs_class *ret;
 320
 321     g_return_val_if_fail(path, NULL);
 322
 323     semi = strrchr (path, '#');
 324     if (!semi || !path_magic (path))
 325         return NULL;
 326
 327     slash = strchr (semi, PATH_SEP);
 328     *semi = 0;
 329     if (slash)
 330         *slash = 0;
 331
 332     ret = vfs_prefix_to_class (semi+1);
 333
 334     if (slash)
 335         *slash = PATH_SEP;
 336     if (!ret)
 337         ret = _vfs_get_class (path);
 338
 339     *semi = '#';
 340     return ret;
 341 }
 342
 343 struct vfs_class *
 344 vfs_get_class (const char *pathname)
 345 {
 346     struct vfs_class *vfs;
 347     char *path = g_strdup (pathname);
 348
 349     vfs = _vfs_get_class (path);
 350     g_free (path);
 351
 352     if (!vfs)
 353         vfs = localfs_class;
 354
 355     return vfs;
 356 }
 357
 358 const char *
 359 vfs_get_encoding (const char *path)
 360 {
 361     static char result[16];
 362     char *work;
 363     char *semi;
 364     char *slash;
 365
 366     work = g_strdup (path);
 367     semi = g_strrstr (work, "#enc:");
 368
 369     if (semi != NULL) {
 370         semi+= 5 * sizeof (char);
 371         slash = strchr (semi, PATH_SEP);
 372         if (slash != NULL)
 373             slash[0] = '\0';
 374
 375         g_strlcpy (result, semi, sizeof(result));
 376         g_free (work);
 377         return result;
 378     }  else {
 379         g_free (work);
 380         return NULL;
 381     }
 382 }
 383
 384 /* return if encoding can by used in vfs (is ascci full compactible) */
 385 /* contains only a few encoding now */
 386 static int
 387 vfs_supported_enconding (const char *encoding) {
 388     int t;
 389     int result = 0;
 390
 391     for (t = 0; supported_encodings[t] != NULL; t++) {
 392         result+= (g_ascii_strncasecmp (encoding, supported_encodings[t],
 393                   strlen (supported_encodings[t])) == 0);
 394     }
 395
 396     return result;
 397 }
 398
 399 /* now used only by vfs_translate_path, but could be used in other vfs
 400  * plugin to automatic detect encoding
 401  * path - path to translate
 402  * size - how many bytes from path translate
 403  * defcnv - convertor, that is used as default, when path does not contain any
 404  *          #enc: subtring
 405  * buffer - used to store result of translation
 406  */
 407 static estr_t
 408 _vfs_translate_path (const char *path, int size,
 409                      GIConv defcnv, GString *buffer)
 410 {
 411     const char *semi;
 412     const char *ps;
 413     const char *slash;
 414     estr_t state = ESTR_SUCCESS;
 415     static char encoding[16];
 416     GIConv coder;
 417     int ms;
 418
 419     if (size == 0) return 0;
 420     size = ( size > 0) ? size : (signed int)strlen (path);
 421
 422     /* try found #end: */
 423     semi = g_strrstr_len (path, size, "#enc:");
 424     if (semi != NULL) {
 425         /* first must be translated part before #enc: */
 426         ms = semi - path;
 427
 428         /* remove '/' before #enc */
 429         ps = str_cget_prev_char (semi);
 430         if (ps[0] == PATH_SEP) ms = ps - path;
 431
 432         state = _vfs_translate_path (path, ms, defcnv, buffer);
 433
 434         if (state != ESTR_SUCCESS)
 435             return state;
 436         /* now can be translated part after #enc: */
 437
 438         semi+= 5;
 439         slash = strchr (semi, PATH_SEP);
 440         /* ignore slashes after size; */
 441         if (slash - path >= size) slash = NULL;
 442
 443         ms = (slash != NULL) ? slash - semi : (int) strlen (semi);
 444         ms = min ((unsigned int) ms, sizeof (encoding) - 1);
 445         /* limit encoding size (ms) to path size (size) */
 446         if (semi + ms > path + size) ms = path + size - semi;
 447         memcpy (encoding, semi, ms);
 448         encoding[ms] = '\0';
 449
 450         switch (vfs_supported_enconding (encoding)) {
 451             case 1:
 452                 coder = str_crt_conv_to (encoding);
 453                 if (coder != INVALID_CONV)  {
 454                     if (slash != NULL) {
 455                         state = str_vfs_convert_to (coder, slash,
 456                                 path + size - slash, buffer);
 457                     } else if (buffer->str[0] == '\0') {
 458                         /* exmaple "/#enc:utf-8" */
 459                         g_string_append_c(buffer, PATH_SEP);
 460                     }
 461                     str_close_conv (coder);
 462                     return state;
 463                 } else {
 464                     errno = EINVAL;
 465                     return ESTR_FAILURE;
 466                 }
 467                 break;
 468             default:
 469                 errno = EINVAL;
 470                 return ESTR_FAILURE;
 471         }
 472     } else {
 473         /* path can be translated whole at once */
 474         state = str_vfs_convert_to (defcnv, path, size, buffer);
 475         return state;
 476     }
 477
 478     return ESTR_SUCCESS;
 479 }
 480
 481 char *
 482 vfs_translate_path (const char *path)
 483 {
 484     estr_t state;
 485
 486     g_string_set_size(vfs_str_buffer,0);
 487     state = _vfs_translate_path (path, -1, str_cnv_from_term, vfs_str_buffer);
 488     /*
 489      strict version
 490      return (state == 0) ? vfs_str_buffer->data : NULL;
 491     */
 492     return (state != ESTR_FAILURE) ? vfs_str_buffer->str : NULL;
 493 }
 494
 495 char *
 496 vfs_translate_path_n (const char *path)
 497 {
 498     char *result;
 499
 500     result = vfs_translate_path (path);
 501     return (result != NULL) ? g_strdup (result) : NULL;
 502 }
 503
 504 char *
 505 vfs_canon_and_translate (const char *path)
 506 {
 507     char *canon;
 508     char *result;
 509     if (path == NULL)
 510         canon = g_strdup ("");
 511     else
 512         canon = vfs_canon (path);
 513     result = vfs_translate_path_n (canon);
 514     g_free (canon);
 515     return result;
 516 }
 517
 518 static int
 519 ferrno (struct vfs_class *vfs)
 520 {
 521     return vfs->ferrno ? (*vfs->ferrno)(vfs) : E_UNKNOWN;
 522     /* Hope that error message is obscure enough ;-) */
 523 }
 524
 525 int
 526 mc_open (const char *filename, int flags, ...)
 527 {
 528     int  mode;
 529     void *info;
 530     va_list ap;
 531
 532     char *file = vfs_canon_and_translate (filename);
 533     if (file != NULL) {
 534     struct vfs_class *vfs = vfs_get_class (file);
 535
 536     /* Get the mode flag */
 537     if (flags & O_CREAT) {
 538         va_start (ap, flags);
 539         mode = va_arg (ap, int);
 540         va_end (ap);
 541     } else
 542         mode = 0;
 543
 544     if (!vfs->open) {
 545         g_free (file);
 546         errno = -EOPNOTSUPP;
 547         return -1;
 548     }
 549
 550     info = (*vfs->open) (vfs, file, flags, mode);       /* open must be supported */
 551     g_free (file);
 552     if (!info){
 553         errno = ferrno (vfs);
 554         return -1;
 555     }
 556
 557     return vfs_new_handle (vfs, info);
 558     } else return -1;
 559 }
 560
 561
 562 #define MC_NAMEOP(name, inarg, callarg) \
 563 int mc_##name inarg \
 564 { \
 565     struct vfs_class *vfs; \
 566     int result; \
 567     char *mpath = vfs_canon_and_translate (path); \
 568     if (mpath != NULL) { \
 569     vfs = vfs_get_class (mpath); \
 570     if (vfs == NULL){ \
 571         g_free (mpath); \
 572         return -1; \
 573     } \
 574     result = vfs->name ? (*vfs->name)callarg : -1; \
 575     g_free (mpath); \
 576     if (result == -1) \
 577         errno = vfs->name ? ferrno (vfs) : E_NOTSUPP; \
 578     return result; \
 579     } else return -1; \
 580 }
 581
 582 MC_NAMEOP (chmod, (const char *path, mode_t mode), (vfs, mpath, mode))
 583 MC_NAMEOP (chown, (const char *path, uid_t owner, gid_t group), (vfs, mpath, owner, group))
 584 MC_NAMEOP (utime, (const char *path, struct utimbuf *times), (vfs, mpath, times))
 585 MC_NAMEOP (readlink, (const char *path, char *buf, int bufsiz), (vfs, mpath, buf, bufsiz))
 586 MC_NAMEOP (unlink, (const char *path), (vfs, mpath))
 587 MC_NAMEOP (mkdir, (const char *path, mode_t mode), (vfs, mpath, mode))
 588 MC_NAMEOP (rmdir, (const char *path), (vfs, mpath))
 589 MC_NAMEOP (mknod, (const char *path, mode_t mode, dev_t dev), (vfs, mpath, mode, dev))
 590
 591 int
 592 mc_symlink (const char *name1, const char *path)
 593 {
 594     struct vfs_class *vfs;
 595     int result;
 596     char *mpath;
 597     char *lpath;
 598     char *tmp;
 599
 600     mpath = vfs_canon_and_translate (path);
 601     if (mpath != NULL) {
 602         tmp = g_strdup (name1);
 603         lpath = vfs_translate_path_n (tmp);
 604         g_free (tmp);
 605
 606         if (lpath != NULL) {
 607             vfs = vfs_get_class (mpath);
 608             result = vfs->symlink ? (*vfs->symlink) (vfs, lpath, mpath) : -1;
 609             g_free (lpath);
 610
 611             if (result == -1)
 612                 errno = vfs->symlink ? ferrno (vfs) : E_NOTSUPP;
 613             return result;
 614         }
 615         g_free (mpath);
 616     }
 617     return -1;
 618 }
 619
 620 #define MC_HANDLEOP(name, inarg, callarg) \
 621 ssize_t mc_##name inarg \
 622 { \
 623     struct vfs_class *vfs; \
 624     int result; \
 625     if (handle == -1) \
 626         return -1; \
 627     vfs = vfs_op (handle); \
 628     if (vfs == NULL) \
 629          return -1; \
 630     result = vfs->name ? (*vfs->name)callarg : -1; \
 631     if (result == -1) \
 632         errno = vfs->name ? ferrno (vfs) : E_NOTSUPP; \
 633     return result; \
 634 }
 635
 636 MC_HANDLEOP(read,  (int handle, void *buffer,    int count), (vfs_info (handle), buffer, count))
 637 MC_HANDLEOP(write, (int handle, const void *buf, int nbyte), (vfs_info (handle), buf,    nbyte))
 638
 639
 640 #define MC_RENAMEOP(name) \
 641 int mc_##name (const char *fname1, const char *fname2) \
 642 { \
 643     struct vfs_class *vfs; \
 644     int result; \
 645     char *name2, *name1; \
 646     name1 = vfs_canon_and_translate (fname1); \
 647     if (name1 != NULL) { \
 648         name2 = vfs_canon_and_translate (fname2); \
 649         if (name2 != NULL) { \
 650     vfs = vfs_get_class (name1); \
 651     if (vfs != vfs_get_class (name2)){ \
 652         errno = EXDEV; \
 653         g_free (name1); \
 654         g_free (name2); \
 655         return -1; \
 656     } \
 657     result = vfs->name ? (*vfs->name)(vfs, name1, name2) : -1; \
 658     g_free (name1); \
 659     g_free (name2); \
 660     if (result == -1) \
 661         errno = vfs->name ? ferrno (vfs) : E_NOTSUPP; \
 662     return result; \
 663     } else { \
 664         g_free (name1); \
 665         return -1; \
 666     } \
 667     } else return -1; \
 668 }
 669
 670 MC_RENAMEOP (link)
 671 MC_RENAMEOP (rename)
 672
 673
 674 int
 675 mc_ctl (int handle, int ctlop, void *arg)
 676 {
 677     struct vfs_class *vfs = vfs_op (handle);
 678
 679     return vfs->ctl ? (*vfs->ctl)(vfs_info (handle), ctlop, arg) : 0;
 680 }
 681
 682 int
 683 mc_setctl (const char *path, int ctlop, void *arg)
 684 {
 685     struct vfs_class *vfs;
 686     int result;
 687     char *mpath;
 688
 689     if (!path)
 690         vfs_die("You don't want to pass NULL to mc_setctl.");
 691
 692     mpath = vfs_canon_and_translate (path);
 693     if (mpath != NULL) {
 694     vfs = vfs_get_class (mpath);
 695     result = vfs->setctl ? (*vfs->setctl)(vfs, mpath, ctlop, arg) : 0;
 696     g_free (mpath);
 697     return result;
 698     } else return -1;
 699 }
 700
 701 int
 702 mc_close (int handle)
 703 {
 704     struct vfs_class *vfs;
 705     int result;
 706
 707     if (handle == -1 || !vfs_info (handle))
 708         return -1;
 709
 710     vfs = vfs_op (handle);
 711     if (handle < 3)
 712         return close (handle);
 713
 714     if (!vfs->close)
 715         vfs_die ("VFS must support close.\n");
 716     result = (*vfs->close)(vfs_info (handle));
 717     vfs_free_handle (handle);
 718     if (result == -1)
 719         errno = ferrno (vfs);
 720
 721     return result;
 722 }
 723
 724 DIR *
 725 mc_opendir (const char *dirname)
 726 {
 727     int  handle, *handlep;
 728     void *info;
 729     struct vfs_class *vfs;
 730     char *canon;
 731     char *dname;
 732     struct vfs_dirinfo *dirinfo;
 733     const char *encoding;
 734
 735     canon = vfs_canon (dirname);
 736     dname = vfs_translate_path_n (canon);
 737
 738     if (dname != NULL) {
 739         vfs = vfs_get_class (dname);
 740     info = vfs->opendir ? (*vfs->opendir)(vfs, dname) : NULL;
 741     g_free (dname);
 742
 743     if (!info){
 744         errno = vfs->opendir ? ferrno (vfs) : E_NOTSUPP;
 745             g_free (canon);
 746         return NULL;
 747     }
 748
 749         dirinfo = g_new (struct vfs_dirinfo, 1);
 750         dirinfo->info = info;
 751
 752         encoding = vfs_get_encoding (canon);
 753         g_free (canon);
 754         dirinfo->converter = (encoding != NULL) ? str_crt_conv_from (encoding) :
 755                 str_cnv_from_term;
 756         if (dirinfo->converter == INVALID_CONV) dirinfo->converter =str_cnv_from_term;
 757
 758         handle = vfs_new_handle (vfs, dirinfo);
 759
 760     handlep = g_new (int, 1);
 761     *handlep = handle;
 762     return (DIR *) handlep;
 763     } else {
 764         g_free (canon);
 765         return NULL;
 766     }
 767 }
 768
 769 static struct dirent * mc_readdir_result = NULL;
 770
 771 struct dirent *
 772 mc_readdir (DIR *dirp)
 773 {
 774     int handle;
 775     struct vfs_class *vfs;
 776     struct dirent *entry = NULL;
 777     struct vfs_dirinfo *dirinfo;
 778     estr_t state;
 779
 780     if (!mc_readdir_result)
 781     {
 782         /* We can't just allocate struct dirent as (see man dirent.h)
 783          * struct dirent has VERY nonnaive semantics of allocating
 784          * d_name in it. Moreover, linux's glibc-2.9 allocates dirents _less_,
 785          * than 'sizeof (struct dirent)' making full bitwise (sizeof dirent) copy
 786          * heap corrupter. So, allocate longliving dirent with at least
 787          * (NAME_MAX + 1) for d_name in it.
 788          * Strictly saying resulting dirent is unusable as we don't adjust internal
 789          * structures, holding dirent size. But we don't use it in libc infrastructure.
 790          * TODO: to make simpler homemade dirent-alike structure.
 791          */
 792         mc_readdir_result = (struct dirent *)malloc(sizeof(struct dirent) + NAME_MAX + 1);
 793     }
 794
 795     if (!dirp) {
 796         errno = EFAULT;
 797         return NULL;
 798     }
 799     handle = *(int *) dirp;
 800     vfs = vfs_op (handle);
 801     dirinfo = vfs_info (handle);
 802     if (vfs->readdir) {
 803         entry = (*vfs->readdir) (dirinfo->info);
 804         if (entry == NULL) return NULL;
 805         g_string_set_size(vfs_str_buffer,0);
 806         state = str_vfs_convert_from (dirinfo->converter,
 807                                           entry->d_name, vfs_str_buffer);
 808         mc_readdir_result->d_ino = entry->d_ino;
 809         g_strlcpy (mc_readdir_result->d_name, vfs_str_buffer->str, NAME_MAX + 1);
 810     }
 811     if (entry == NULL) errno = vfs->readdir ? ferrno (vfs) : E_NOTSUPP;
 812     return (entry != NULL) ? mc_readdir_result : NULL;
 813 }
 814
 815 int
 816 mc_closedir (DIR *dirp)
 817 {
 818     int handle = *(int *) dirp;
 819     struct vfs_class *vfs = vfs_op (handle);
 820     int result;
 821     struct vfs_dirinfo *dirinfo;
 822
 823     dirinfo = vfs_info (handle);
 824     if (dirinfo->converter != str_cnv_from_term) str_close_conv (dirinfo->converter);
 825
 826     result = vfs->closedir ? (*vfs->closedir)(dirinfo->info) : -1;
 827     vfs_free_handle (handle);
 828     g_free (dirinfo);
 829     g_free (dirp);
 830     return result;
 831 }
 832
 833 int mc_stat (const char *filename, struct stat *buf) {
 834     struct vfs_class *vfs;
 835     int result;
 836     char *path;
 837
 838     path = vfs_canon_and_translate (filename);
 839
 840     if (path != NULL) {
 841         vfs = vfs_get_class (path);
 842
 843     result = vfs->stat ? (*vfs->stat) (vfs, path, buf) : -1;
 844
 845     g_free (path);
 846
 847     if (result == -1)
 848         errno = vfs->name ? ferrno (vfs) : E_NOTSUPP;
 849     return result;
 850     } else return -1;
 851 }
 852
 853 int mc_lstat (const char *filename, struct stat *buf) {
 854     struct vfs_class *vfs;
 855     int result;
 856     char *path;
 857
 858     path = vfs_canon_and_translate (filename);
 859
 860     if (path != NULL) {
 861         vfs = vfs_get_class (path);
 862     result = vfs->lstat ? (*vfs->lstat) (vfs, path, buf) : -1;
 863     g_free (path);
 864     if (result == -1)
 865         errno = vfs->name ? ferrno (vfs) : E_NOTSUPP;
 866     return result;
 867     } else return -1;
 868 }
 869
 870 int mc_fstat (int handle, struct stat *buf) {
 871     struct vfs_class *vfs;
 872     int result;
 873
 874     if (handle == -1)
 875         return -1;
 876     vfs = vfs_op (handle);
 877     result = vfs->fstat ? (*vfs->fstat) (vfs_info (handle), buf) : -1;
 878     if (result == -1)
 879         errno = vfs->name ? ferrno (vfs) : E_NOTSUPP;
 880     return result;
 881 }
 882
 883 /**
 884  * Return current directory.  If it's local, reread the current directory
 885  * from the OS.  You must g_strdup() whatever this function returns.
 886  */
 887 static const char *
 888 _vfs_get_cwd (void)
 889 {
 890     char *sys_cwd;
 891     char *trans;
 892     const char *encoding;
 893     char *tmp;
 894     estr_t state;
 895     struct stat my_stat, my_stat2;
 896
 897     trans = vfs_translate_path_n (current_dir); /* add check if NULL */
 898
 899     if (!_vfs_get_class (trans)) {
 900         encoding = vfs_get_encoding (current_dir);
 901         if (encoding == NULL) {
 902             tmp = g_get_current_dir ();
 903             if (tmp != NULL) { /* One of the directories in the path is not readable */
 904                 g_string_set_size(vfs_str_buffer,0);
 905                 state = str_vfs_convert_from (str_cnv_from_term, tmp, vfs_str_buffer);
 906                 g_free (tmp);
 907                 sys_cwd = (state == ESTR_SUCCESS) ? g_strdup (vfs_str_buffer->str) : NULL;
 908                 if (!sys_cwd)
 909                     return current_dir;
 910
 911         /* Otherwise check if it is O.K. to use the current_dir */
 912                 if (!cd_symlinks || mc_stat (sys_cwd, &my_stat)
 913             || mc_stat (current_dir, &my_stat2)
 914             || my_stat.st_ino != my_stat2.st_ino
 915             || my_stat.st_dev != my_stat2.st_dev) {
 916             g_free (current_dir);
 917                     current_dir = sys_cwd;
 918                     return sys_cwd;
 919                      }/* Otherwise we return current_dir below */
 920             }
 921     }
 922     }
 923     g_free (trans);
 924     return current_dir;
 925 }
 926
 927 static void
 928 vfs_setup_wd (void)
 929 {
 930     current_dir = g_strdup (PATH_SEP_STR);
 931     _vfs_get_cwd ();
 932
 933     if (strlen (current_dir) > MC_MAXPATHLEN - 2)
 934         vfs_die ("Current dir too long.\n");
 935
 936     current_vfs = vfs_get_class (current_dir);
 937 }
 938
 939 /**
 940  * Return current directory. If it's local, reread the current directory
 941  * from the OS. Put directory to the provided buffer.
 942  */
 943 char *
 944 mc_get_current_wd (char *buffer, int size)
 945 {
 946     const char *cwd = _vfs_get_cwd ();
 947
 948     g_strlcpy (buffer, cwd, size);
 949     return buffer;
 950 }
 951
 952 /**
 953  * Return current directory without any OS calls.
 954  */
 955 char *
 956 vfs_get_current_dir (void)
 957 {
 958     return current_dir;
 959 }
 960
 961 off_t mc_lseek (int fd, off_t offset, int whence)
 962 {
 963     struct vfs_class *vfs;
 964     int result;
 965
 966     if (fd == -1)
 967         return -1;
 968
 969     vfs = vfs_op (fd);
 970     result = vfs->lseek ? (*vfs->lseek)(vfs_info (fd), offset, whence) : -1;
 971     if (result == -1)
 972         errno = vfs->lseek ? ferrno (vfs) : E_NOTSUPP;
 973     return result;
 974 }
 975
 976 /**
 977  * remove //, /./ and /../
 978  */
 979
 980 #define ISSLASH(a) (!a || (a == '/'))
 981
 982 char *
 983 vfs_canon (const char *path)
 984 {
 985     if (!path)
 986         vfs_die("Cannot canonicalize NULL");
 987
 988     /* Relative to current directory */
 989     if (*path != PATH_SEP){
 990         char *local, *result;
 991
 992         local = concat_dir_and_file (current_dir, path);
 993
 994         result = vfs_canon (local);
 995         g_free (local);
 996         return result;
 997     }
 998
 999     /*
1000      * So we have path of following form:
1001      * /p1/p2#op/.././././p3#op/p4. Good luck.
1002      */
1003     {
1004         char *result = g_strdup (path);
1005         canonicalize_pathname (result);
1006         return result;
1007     }
1008 }
1009
1010 /**
1011  * VFS chdir.
1012  * Return 0 on success, -1 on failure.
1013  */
1014 int
1015 mc_chdir (const char *path)
1016 {
1017     char *new_dir;
1018     char *trans_dir;
1019     struct vfs_class *old_vfs, *new_vfs;
1020     vfsid old_vfsid;
1021     int result;
1022
1023     new_dir = vfs_canon (path);
1024     trans_dir = vfs_translate_path_n (new_dir);
1025     if (trans_dir != NULL) {
1026         new_vfs = vfs_get_class (trans_dir);
1027     if (!new_vfs->chdir) {
1028         g_free (new_dir);
1029             g_free (trans_dir);
1030         return -1;
1031     }
1032
1033         result = (*new_vfs->chdir) (new_vfs, trans_dir);
1034
1035     if (result == -1) {
1036         errno = ferrno (new_vfs);
1037         g_free (new_dir);
1038             g_free (trans_dir);
1039         return -1;
1040     }
1041
1042     old_vfsid = vfs_getid (current_vfs, current_dir);
1043     old_vfs = current_vfs;
1044
1045     /* Actually change directory */
1046     g_free (current_dir);
1047     current_dir = new_dir;
1048     current_vfs = new_vfs;
1049
1050     /* This function uses the new current_dir implicitly */
1051     vfs_stamp_create (old_vfs, old_vfsid);
1052
1053     /* Sometimes we assume no trailing slash on cwd */
1054     if (*current_dir) {
1055         char *p;
1056         p = strchr (current_dir, 0) - 1;
1057         if (*p == PATH_SEP && p > current_dir)
1058             *p = 0;
1059     }
1060
1061         g_free (trans_dir);
1062     return 0;
1063     } else {
1064         g_free (new_dir);
1065         return -1;
1066     }
1067 }
1068
1069 /* Return 1 is the current VFS class is local */
1070 int
1071 vfs_current_is_local (void)
1072 {
1073     return (current_vfs->flags & VFSF_LOCAL) != 0;
1074 }
1075
1076 /* Return flags of the VFS class of the given filename */
1077 int
1078 vfs_file_class_flags (const char *filename)
1079 {
1080     struct vfs_class *vfs;
1081     char *fname;
1082
1083     fname = vfs_canon_and_translate (filename);
1084     if (fname != NULL) {
1085     vfs = vfs_get_class (fname);
1086     g_free (fname);
1087     return vfs->flags;
1088     } else return -1;
1089 }
1090
1091 static char *
1092 mc_def_getlocalcopy (const char *filename)
1093 {
1094     char *tmp;
1095     int fdin, fdout, i;
1096     char buffer[8192];
1097     struct stat mystat;
1098
1099     fdin = mc_open (filename, O_RDONLY | O_LINEAR);
1100     if (fdin == -1)
1101         return NULL;
1102
1103     fdout = vfs_mkstemps (&tmp, "vfs", filename);
1104
1105     if (fdout == -1)
1106         goto fail;
1107     while ((i = mc_read (fdin, buffer, sizeof (buffer))) > 0) {
1108         if (write (fdout, buffer, i) != i)
1109             goto fail;
1110     }
1111     if (i == -1)
1112         goto fail;
1113     i = mc_close (fdin);
1114     fdin = -1;
1115     if (i == -1)
1116         goto fail;
1117     if (close (fdout) == -1) {
1118         fdout = -1;
1119         goto fail;
1120     }
1121
1122     if (mc_stat (filename, &mystat) != -1) {
1123         chmod (tmp, mystat.st_mode);
1124     }
1125     return tmp;
1126
1127   fail:
1128     if (fdout != -1)
1129         close (fdout);
1130     if (fdin != -1)
1131         mc_close (fdin);
1132     g_free (tmp);
1133     return NULL;
1134 }
1135
1136 char *
1137 mc_getlocalcopy (const char *pathname)
1138 {
1139     char *result;
1140     char *path;
1141
1142     path = vfs_canon_and_translate (pathname);
1143     if (path != NULL) {
1144     struct vfs_class *vfs = vfs_get_class (path);
1145
1146     result = vfs->getlocalcopy ? (*vfs->getlocalcopy)(vfs, path) :
1147                                  mc_def_getlocalcopy (path);
1148     g_free (path);
1149     if (!result)
1150         errno = ferrno (vfs);
1151     return result;
1152     } else return NULL;
1153 }
1154
1155 static int
1156 mc_def_ungetlocalcopy (struct vfs_class *vfs, const char *filename,
1157                        const char *local, int has_changed)
1158 {
1159     int fdin = -1, fdout = -1, i;
1160     if (has_changed) {
1161         char buffer[8192];
1162
1163         if (!vfs->write)
1164             goto failed;
1165
1166         fdin = open (local, O_RDONLY);
1167         if (fdin == -1)
1168             goto failed;
1169         fdout = mc_open (filename, O_WRONLY | O_TRUNC);
1170         if (fdout == -1)
1171             goto failed;
1172         while ((i = read (fdin, buffer, sizeof (buffer))) > 0) {
1173             if (mc_write (fdout, buffer, i) != i)
1174                 goto failed;
1175         }
1176         if (i == -1)
1177             goto failed;
1178
1179         if (close (fdin) == -1) {
1180             fdin = -1;
1181             goto failed;
1182         }
1183         fdin = -1;
1184         if (mc_close (fdout) == -1) {
1185             fdout = -1;
1186             goto failed;
1187         }
1188     }
1189     unlink (local);
1190     return 0;
1191
1192   failed:
1193     message (D_ERROR, _("Changes to file lost"), "%s", filename);
1194     if (fdout != -1)
1195         mc_close (fdout);
1196     if (fdin != -1)
1197         close (fdin);
1198     unlink (local);
1199     return -1;
1200 }
1201
1202 int
1203 mc_ungetlocalcopy (const char *pathname, const char *local, int has_changed)
1204 {
1205     int return_value = 0;
1206     char *path;
1207
1208     path = vfs_canon_and_translate (pathname);
1209     if (path != NULL) {
1210     struct vfs_class *vfs = vfs_get_class (path);
1211
1212     return_value = vfs->ungetlocalcopy ?
1213             (*vfs->ungetlocalcopy)(vfs, path, local, has_changed) :
1214             mc_def_ungetlocalcopy (vfs, path, local, has_changed);
1215     g_free (path);
1216     return return_value;
1217     } else return -1;
1218 }
1219
1220
1221 void
1222 vfs_init (void)
1223 {
1224     /* create the VFS handle array */
1225     vfs_openfiles = g_ptr_array_new ();
1226
1227     vfs_str_buffer = g_string_new("");
1228     /* localfs needs to be the first one */
1229     init_localfs();
1230     /* fallback value for vfs_get_class() */
1231     localfs_class = vfs_list;
1232
1233     init_extfs ();
1234     init_sfs ();
1235     init_tarfs ();
1236     init_cpiofs ();
1237
1238 #ifdef USE_EXT2FSLIB
1239     init_undelfs ();
1240 #endif /* USE_EXT2FSLIB */
1241
1242 #ifdef USE_NETCODE
1243     tcp_init();
1244     init_ftpfs ();
1245     init_fish ();
1246 #ifdef WITH_SMBFS
1247     init_smbfs ();
1248 #endif /* WITH_SMBFS */
1249 #ifdef ENABLE_VFS_MCFS
1250     init_mcfs ();
1251 #endif /* ENABLE_VFS_MCFS */
1252 #endif /* USE_NETCODE */
1253
1254     vfs_setup_wd ();
1255 }
1256
1257 void
1258 vfs_shut (void)
1259 {
1260     struct vfs_class *vfs;
1261
1262     vfs_gc_done ();
1263
1264     g_free (current_dir);
1265
1266     for (vfs = vfs_list; vfs; vfs = vfs->next)
1267         if (vfs->done)
1268             (*vfs->done) (vfs);
1269
1270     g_ptr_array_free (vfs_openfiles, TRUE);
1271
1272     g_string_free (vfs_str_buffer, TRUE);
1273 }
1274
1275 /*
1276  * These ones grab information from the VFS
1277  *  and handles them to an upper layer
1278  */
1279 void
1280 vfs_fill_names (fill_names_f func)
1281 {
1282     struct vfs_class *vfs;
1283
1284     for (vfs=vfs_list; vfs; vfs=vfs->next)
1285         if (vfs->fill_names)
1286             (*vfs->fill_names) (vfs, func);
1287 }
1288
1289 /*
1290  * Returns vfs path corresponding to given url. If passed string is
1291  * not recognized as url, g_strdup(url) is returned.
1292  */
1293
1294 static const struct {
1295     const char *name;
1296     size_t name_len;
1297     const char *substitute;
1298 } url_table[] = { {"ftp://", 6, "/#ftp:"},
1299                   {"mc://", 5, "/#mc:"},
1300                   {"smb://", 6, "/#smb:"},
1301                   {"sh://", 5, "/#sh:"},
1302                   {"ssh://", 6, "/#sh:"},
1303                   {"a:", 2, "/#a"}
1304 };
1305
1306 char *
1307 vfs_translate_url (const char *url)
1308 {
1309     size_t i;
1310
1311     for (i = 0; i < sizeof (url_table)/sizeof (url_table[0]); i++)
1312        if (strncmp (url, url_table[i].name, url_table[i].name_len) == 0)
1313            return g_strconcat (url_table[i].substitute, url + url_table[i].name_len, (char*) NULL);
1314
1315     return g_strdup (url);
1316 }
1317
1318 int vfs_file_is_local (const char *filename)
1319 {
1320     return vfs_file_class_flags (filename) & VFSF_LOCAL;
1321 }