Kernel/vfs/open.c

   1 /*
   2  * AcessMicro VFS
   3  * - Open, Close and ChDir
   4  */
   5 #define DEBUG   0
   6 #include <acess.h>
   7 #include <mm_virt.h>
   8 #include "vfs.h"
   9 #include "vfs_int.h"
  10 #include "vfs_ext.h"
  11
  12 // === CONSTANTS ===
  13 #define OPEN_MOUNT_ROOT 1
  14 #define MAX_KERNEL_FILES        128
  15 #define MAX_PATH_SLASHES        256
  16
  17 // === IMPORTS ===
  18 extern tVFS_Node        gVFS_MemRoot;
  19 extern tVFS_Mount       *gVFS_RootMount;
  20
  21 // === GLOBALS ===
  22 tVFS_Handle     *gaUserHandles = (void*)MM_PPD_VFS;
  23 tVFS_Handle     *gaKernelHandles = (void*)MM_KERNEL_VFS;
  24
  25 // === CODE ===
  26 /**
  27  * \fn char *VFS_GetAbsPath(const char *Path)
  28  * \brief Create an absolute path from a relative one
  29  */
  30 char *VFS_GetAbsPath(const char *Path)
  31 {
  32         char    *ret;
  33          int    pathLen = strlen(Path);
  34         char    *pathComps[MAX_PATH_SLASHES];
  35         char    *tmpStr;
  36         int             iPos = 0;
  37         int             iPos2 = 0;
  38         char    *chroot = CFGPTR(CFG_VFS_CHROOT);
  39          int    chrootLen;
  40         char    *cwd = CFGPTR(CFG_VFS_CWD);
  41          int    cwdLen;
  42
  43         ENTER("sPath", Path);
  44
  45         // Memory File
  46         if(Path[0] == '$') {
  47                 ret = malloc(strlen(Path)+1);
  48                 if(!ret) {
  49                         Warning("VFS_GetAbsPath - malloc() returned NULL");
  50                         return NULL;
  51                 }
  52                 strcpy(ret, Path);
  53                 LEAVE('p', ret);
  54                 return ret;
  55         }
  56
  57         // - Fetch ChRoot
  58         if( chroot == NULL ) {
  59                 chroot = "";
  60                 chrootLen = 0;
  61         } else {
  62                 chrootLen = strlen(chroot);
  63         }
  64
  65         // Check if the path is already absolute
  66         if(Path[0] == '/') {
  67                 ret = malloc(pathLen + 1);
  68                 if(!ret) {
  69                         Warning("VFS_GetAbsPath - malloc() returned NULL");
  70                         return NULL;
  71                 }
  72                 strcpy(ret, Path);
  73         } else {
  74                 if(cwd == NULL) {
  75                         cwd = "/";
  76                         cwdLen = 1;
  77                 }
  78                 else {
  79                         cwdLen = strlen(cwd);
  80                 }
  81                 // Prepend the current directory
  82                 ret = malloc( cwdLen + 1 + pathLen + 1 );
  83                 strcpy(ret, cwd);
  84                 ret[cwdLen] = '/';
  85                 strcpy(&ret[cwdLen+1], Path);
  86                 //Log("ret = '%s'\n", ret);
  87         }
  88
  89         // Parse Path
  90         pathComps[iPos++] = tmpStr = ret+1;
  91         while(*tmpStr)
  92         {
  93                 if(*tmpStr++ == '/')
  94                 {
  95                         pathComps[iPos++] = tmpStr;
  96                         if(iPos == MAX_PATH_SLASHES) {
  97                                 LOG("Path '%s' has too many elements", Path);
  98                                 free(ret);
  99                                 LEAVE('n');
 100                                 return NULL;
 101                         }
 102                 }
 103         }
 104         pathComps[iPos] = NULL;
 105
 106         // Cleanup
 107         iPos2 = iPos = 0;
 108         while(pathComps[iPos])
 109         {
 110                 tmpStr = pathComps[iPos];
 111                 // Always Increment iPos
 112                 iPos++;
 113                 // ..
 114                 if(tmpStr[0] == '.' && tmpStr[1] == '.' && (tmpStr[2] == '/' || tmpStr[2] == '\0') )
 115                 {
 116                         if(iPos2 != 0)
 117                                 iPos2 --;
 118                         continue;
 119                 }
 120                 // .
 121                 if(tmpStr[0] == '.' && (tmpStr[1] == '/' || tmpStr[1] == '\0') )
 122                 {
 123                         continue;
 124                 }
 125                 // Empty
 126                 if(tmpStr[0] == '/' || tmpStr[0] == '\0')
 127                 {
 128                         continue;
 129                 }
 130
 131                 // Set New Position
 132                 pathComps[iPos2] = tmpStr;
 133                 iPos2++;
 134         }
 135         pathComps[iPos2] = NULL;
 136
 137         // Build New Path
 138         iPos2 = 1;      iPos = 0;
 139         ret[0] = '/';
 140         while(pathComps[iPos])
 141         {
 142                 tmpStr = pathComps[iPos];
 143                 while(*tmpStr && *tmpStr != '/')
 144                 {
 145                         ret[iPos2++] = *tmpStr;
 146                         tmpStr++;
 147                 }
 148                 ret[iPos2++] = '/';
 149                 iPos++;
 150         }
 151         if(iPos2 > 1)
 152                 ret[iPos2-1] = 0;
 153         else
 154                 ret[iPos2] = 0;
 155
 156
 157         // Prepend the chroot
 158         tmpStr = malloc(chrootLen + strlen(ret) + 1);
 159         strcpy( tmpStr, chroot );
 160         strcpy( tmpStr+chrootLen, ret );
 161         free(ret);
 162         ret = tmpStr;
 163
 164         LEAVE('s', ret);
 165         //Log("VFS_GetAbsPath: RETURN '%s'", ret);
 166         return ret;
 167 }
 168
 169 /**
 170  * \fn char *VFS_ParsePath(const char *Path, char **TruePath)
 171  * \brief Parses a path, resolving sysmlinks and applying permissions
 172  */
 173 tVFS_Node *VFS_ParsePath(const char *Path, char **TruePath)
 174 {
 175         tVFS_Mount      *mnt;
 176         tVFS_Mount      *longestMount = gVFS_RootMount; // Root is first
 177          int    cmp, retLength = 0;
 178          int    ofs, nextSlash;
 179         tVFS_Node       *curNode, *tmpNode;
 180         char    *tmp;
 181
 182         ENTER("sPath pTruePath", Path, TruePath);
 183
 184         // Memory File
 185         if(Path[0] == '$') {
 186                 if(TruePath) {
 187                         *TruePath = malloc(strlen(Path)+1);
 188                         strcpy(*TruePath, Path);
 189                 }
 190                 curNode = gVFS_MemRoot.FindDir(&gVFS_MemRoot, Path);
 191                 LEAVE('p', curNode);
 192                 return curNode;
 193         }
 194
 195         // For root we always fast return
 196         if(Path[0] == '/' && Path[1] == '\0') {
 197                 if(TruePath) {
 198                         *TruePath = malloc( gVFS_RootMount->MountPointLen+1 );
 199                         strcpy(*TruePath, gVFS_RootMount->MountPoint);
 200                 }
 201                 LEAVE('p', gVFS_RootMount->RootNode);
 202                 return gVFS_RootMount->RootNode;
 203         }
 204
 205         // Check if there is an`ything mounted
 206         if(!gVFS_Mounts) {
 207                 Warning("WTF! There's nothing mounted?");
 208                 return NULL;
 209         }
 210
 211         // Find Mountpoint
 212         for(mnt = gVFS_Mounts;
 213                 mnt;
 214                 mnt = mnt->Next)
 215         {
 216                 // Quick Check
 217                 if( Path[mnt->MountPointLen] != '/' && Path[mnt->MountPointLen] != '\0')
 218                         continue;
 219                 // Length Check - If the length is smaller than the longest match sofar
 220                 if(mnt->MountPointLen < longestMount->MountPointLen)    continue;
 221                 // String Compare
 222                 cmp = strcmp(Path, mnt->MountPoint);
 223
 224                 #if OPEN_MOUNT_ROOT
 225                 // Fast Break - Request Mount Root
 226                 if(cmp == 0) {
 227                         if(TruePath) {
 228                                 *TruePath = malloc( mnt->MountPointLen+1 );
 229                                 strcpy(*TruePath, mnt->MountPoint);
 230                         }
 231                         LEAVE('p', mnt->RootNode);
 232                         return mnt->RootNode;
 233                 }
 234                 #endif
 235                 // Not a match, continue
 236                 if(cmp != '/')  continue;
 237                 longestMount = mnt;
 238         }
 239
 240         // Sanity Check
 241         /*if(!longestMount) {
 242                 Log("VFS_ParsePath - ERROR: No Root Node\n");
 243                 return NULL;
 244         }*/
 245
 246         // Save to shorter variable
 247         mnt = longestMount;
 248
 249         LOG("mnt = {MountPoint:\"%s\"}", mnt->MountPoint);
 250
 251         // Initialise String
 252         if(TruePath)
 253         {
 254                 *TruePath = malloc( mnt->MountPointLen+1 );
 255                 strcpy(*TruePath, mnt->MountPoint);
 256                 retLength = mnt->MountPointLen;
 257         }
 258
 259         curNode = mnt->RootNode;
 260         curNode->ReferenceCount ++;
 261         // Parse Path
 262         ofs = mnt->MountPointLen+1;
 263         for(; (nextSlash = strpos(&Path[ofs], '/')) != -1; ofs += nextSlash + 1)
 264         {
 265                 char    pathEle[nextSlash+1];
 266
 267                 // Empty String
 268                 if(nextSlash == 0)      continue;
 269
 270                 memcpy(pathEle, &Path[ofs], nextSlash);
 271                 pathEle[nextSlash] = 0;
 272
 273                 // Check permissions on root of filesystem
 274                 if( !VFS_CheckACL(curNode, VFS_PERM_EXECUTE) ) {
 275                         if(curNode->Close)      curNode->Close( curNode );
 276                         if(TruePath) {
 277                                 free(*TruePath);
 278                                 *TruePath = NULL;
 279                         }
 280                         //Log("Permissions fail on '%s'", Path);
 281                         LEAVE('n');
 282                         return NULL;
 283                 }
 284
 285                 // Check if the node has a FindDir method
 286                 if( !curNode->FindDir )
 287                 {
 288                         if(curNode->Close)      curNode->Close(curNode);
 289                         if(TruePath) {
 290                                 free(*TruePath);
 291                                 *TruePath = NULL;
 292                         }
 293                         //Log("FindDir fail on '%s'", Path);
 294                         LEAVE('n');
 295                         return NULL;
 296                 }
 297                 LOG("FindDir(%p, '%s')", curNode, pathEle);
 298                 // Get Child Node
 299                 tmpNode = curNode->FindDir(curNode, pathEle);
 300                 LOG("tmpNode = %p", tmpNode);
 301                 if(curNode->Close)      curNode->Close(curNode);
 302                 curNode = tmpNode;
 303
 304                 // Error Check
 305                 if(!curNode) {
 306                         LOG("Node '%s' not found in dir '%s'", pathEle, Path);
 307                         if(TruePath) {
 308                                 free(*TruePath);
 309                                 *TruePath = NULL;
 310                         }
 311                         //Log("Child fail on '%s' ('%s)", Path, pathEle);
 312                         LEAVE('n');
 313                         return NULL;
 314                 }
 315
 316                 // Handle Symbolic Links
 317                 if(curNode->Flags & VFS_FFLAG_SYMLINK) {
 318                         if(TruePath) {
 319                                 free(*TruePath);
 320                                 *TruePath = NULL;
 321                         }
 322                         if(!curNode->Read) {
 323                                 Warning("VFS_ParsePath - Read of node %p is NULL (%s)",
 324                                         curNode, Path);
 325                                 if(curNode->Close)      curNode->Close(curNode);
 326                                 // No need to free *TruePath, see above
 327                                 LEAVE('n');
 328                                 return NULL;
 329                         }
 330
 331                         tmp = malloc( curNode->Size + 1 );
 332                         if(!tmp) {
 333                                 Log_Warning("VFS", "VFS_ParsePath - Malloc failure");
 334                                 // No need to free *TruePath, see above
 335                                 LEAVE('n');
 336                                 return NULL;
 337                         }
 338                         curNode->Read( curNode, 0, curNode->Size, tmp );
 339                         tmp[ curNode->Size ] = '\0';
 340
 341                         // Parse Symlink Path
 342                         curNode = VFS_ParsePath(tmp, TruePath);
 343                         if(TruePath)
 344                                 LOG("VFS", "*TruePath='%s'", *TruePath);
 345
 346                         // Error Check
 347                         if(!curNode) {
 348                                 Log_Debug("VFS", "Symlink fail '%s'", tmp);
 349                                 free(tmp);      // Free temp string
 350                                 if(TruePath)    free(TruePath);
 351                                 LEAVE('n');
 352                                 return NULL;
 353                         }
 354
 355                         // Free temp link
 356                         free(tmp);
 357
 358                         // Set Path Variable
 359                         if(TruePath) {
 360                                 retLength = strlen(*TruePath);
 361                         }
 362
 363                         continue;
 364                 }
 365
 366                 // Handle Non-Directories
 367                 if( !(curNode->Flags & VFS_FFLAG_DIRECTORY) )
 368                 {
 369                         Warning("VFS_ParsePath - File in directory context");
 370                         if(TruePath)    free(*TruePath);
 371                         LEAVE('n');
 372                         return NULL;
 373                 }
 374
 375                 // Check if path needs extending
 376                 if(!TruePath)   continue;
 377
 378                 // Increase buffer space
 379                 tmp = realloc( *TruePath, retLength + strlen(pathEle) + 1 + 1 );
 380                 // Check if allocation succeeded
 381                 if(!tmp) {
 382                         Warning("VFS_ParsePath -  Unable to reallocate true path buffer");
 383                         free(*TruePath);
 384                         *TruePath = NULL;
 385                         if(curNode->Close)      curNode->Close(curNode);
 386                         LEAVE('n');
 387                         return NULL;
 388                 }
 389                 *TruePath = tmp;
 390                 // Append to path
 391                 (*TruePath)[retLength] = '/';
 392                 strcpy(*TruePath+retLength+1, pathEle);
 393
 394                 LOG("*TruePath = '%s'\n", *TruePath);
 395
 396                 // - Extend Path
 397                 retLength += nextSlash + 1;
 398         }
 399
 400         // Get last node
 401         LOG("VFS_ParsePath: FindDir(%p, '%s')", curNode, &Path[ofs]);
 402         tmpNode = curNode->FindDir(curNode, &Path[ofs]);
 403         LOG("tmpNode = %p", tmpNode);
 404         if(curNode->Close)      curNode->Close(curNode);
 405         // Check if file was found
 406         if(!tmpNode) {
 407                 LOG("Node '%s' not found in dir '%s'", &Path[ofs], Path);
 408                 //Log("Child fail '%s' ('%s')", Path, &Path[ofs]);
 409                 if(TruePath)    free(*TruePath);
 410                 if(curNode->Close)      curNode->Close(curNode);
 411                 LEAVE('n');
 412                 return NULL;
 413         }
 414
 415         if(TruePath)
 416         {
 417                 // Increase buffer space
 418                 tmp = realloc(*TruePath, retLength + strlen(&Path[ofs]) + 1 + 1);
 419                 // Check if allocation succeeded
 420                 if(!tmp) {
 421                         Warning("VFS_ParsePath -  Unable to reallocate true path buffer");
 422                         free(*TruePath);
 423                         if(tmpNode->Close)      tmpNode->Close(curNode);
 424                         LEAVE('n');
 425                         return NULL;
 426                 }
 427                 *TruePath = tmp;
 428                 // Append to path
 429                 (*TruePath)[retLength] = '/';
 430                 strcpy(*TruePath + retLength + 1, &Path[ofs]);
 431                 // - Extend Path
 432                 //retLength += strlen(tmpNode->Name) + 1;
 433         }
 434
 435         LEAVE('p', tmpNode);
 436         return tmpNode;
 437 }
 438
 439 /**
 440  * \fn int VFS_Open(char *Path, Uint Mode)
 441  * \brief Open a file
 442  */
 443 int VFS_Open(char *Path, Uint Mode)
 444 {
 445         tVFS_Node       *node;
 446         char    *absPath;
 447          int    i;
 448
 449         ENTER("sPath xMode", Path, Mode);
 450
 451         // Get absolute path
 452         absPath = VFS_GetAbsPath(Path);
 453         LOG("absPath = \"%s\"", absPath);
 454         // Parse path and get mount point
 455         node = VFS_ParsePath(absPath, NULL);
 456         // Free generated path
 457         free(absPath);
 458
 459         if(!node) {
 460                 LOG("Cannot find node");
 461                 LEAVE('i', -1);
 462                 return -1;
 463         }
 464
 465         // Check for symlinks
 466         if( !(Mode & VFS_OPENFLAG_NOLINK) && (node->Flags & VFS_FFLAG_SYMLINK) )
 467         {
 468                 if( !node->Read ) {
 469                         Warning("No read method on symlink");
 470                         LEAVE('i', -1);
 471                         return -1;
 472                 }
 473                 absPath = malloc(node->Size+1); // Allocate Buffer
 474                 node->Read( node, 0, node->Size, absPath );     // Read Path
 475
 476                 absPath[ node->Size ] = '\0';   // End String
 477                 if(node->Close) node->Close( node );    // Close old node
 478                 node = VFS_ParsePath(absPath, NULL);    // Get new node
 479                 free( absPath );        // Free allocated path
 480         }
 481
 482         if(!node) {
 483                 LOG("Cannot find node");
 484                 LEAVE('i', -1);
 485                 return -1;
 486         }
 487
 488         i = 0;
 489         i |= (Mode & VFS_OPENFLAG_EXEC) ? VFS_PERM_EXECUTE : 0;
 490         i |= (Mode & VFS_OPENFLAG_READ) ? VFS_PERM_READ : 0;
 491         i |= (Mode & VFS_OPENFLAG_WRITE) ? VFS_PERM_WRITE : 0;
 492
 493         LOG("i = 0b%b", i);
 494
 495         // Permissions Check
 496         if( !VFS_CheckACL(node, i) ) {
 497                 if(node->Close) node->Close( node );
 498                 Log("VFS_Open: Permissions Failed");
 499                 LEAVE('i', -1);
 500                 return -1;
 501         }
 502
 503         // Check for a user open
 504         if(Mode & VFS_OPENFLAG_USER)
 505         {
 506                 // Allocate Buffer
 507                 if( MM_GetPhysAddr( (Uint)gaUserHandles ) == 0 )
 508                 {
 509                         Uint    addr, size;
 510                         size = CFGINT(CFG_VFS_MAXFILES) * sizeof(tVFS_Handle);
 511                         for(addr = 0; addr < size; addr += 0x1000)
 512                                 MM_Allocate( (Uint)gaUserHandles + addr );
 513                         memset( gaUserHandles, 0, size );
 514                 }
 515                 // Get a handle
 516                 for(i=0;i<CFGINT(CFG_VFS_MAXFILES);i++)
 517                 {
 518                         if(gaUserHandles[i].Node)       continue;
 519                         gaUserHandles[i].Node = node;
 520                         gaUserHandles[i].Position = 0;
 521                         gaUserHandles[i].Mode = Mode;
 522                         LEAVE('i', i);
 523                         return i;
 524                 }
 525         }
 526         else
 527         {
 528                 // Allocate space if not already
 529                 if( MM_GetPhysAddr( (Uint)gaKernelHandles ) == 0 )
 530                 {
 531                         Uint    addr, size;
 532                         size = MAX_KERNEL_FILES * sizeof(tVFS_Handle);
 533                         for(addr = 0; addr < size; addr += 0x1000)
 534                                 MM_Allocate( (Uint)gaKernelHandles + addr );
 535                         memset( gaKernelHandles, 0, size );
 536                 }
 537                 // Get a handle
 538                 for(i=0;i<MAX_KERNEL_FILES;i++)
 539                 {
 540                         if(gaKernelHandles[i].Node)     continue;
 541                         gaKernelHandles[i].Node = node;
 542                         gaKernelHandles[i].Position = 0;
 543                         gaKernelHandles[i].Mode = Mode;
 544                         LEAVE('x', i|VFS_KERNEL_FLAG);
 545                         return i|VFS_KERNEL_FLAG;
 546                 }
 547         }
 548
 549         Log("VFS_Open: Out of handles");
 550         LEAVE('i', -1);
 551         return -1;
 552 }
 553
 554
 555 /**
 556  * \brief Open a file from an open directory
 557  */
 558 int VFS_OpenChild(Uint *Errno, int FD, char *Name, Uint Mode)
 559 {
 560         tVFS_Handle     *h;
 561         tVFS_Node       *node;
 562          int    i;
 563
 564         // Get handle
 565         h = VFS_GetHandle(FD);
 566         if(h == NULL) {
 567                 Log_Warning("VFS", "VFS_OpenChild - Invalid file handle 0x%x", FD);
 568                 if(Errno)       *Errno = EINVAL;
 569                 LEAVE('i', -1);
 570                 return -1;
 571         }
 572
 573         // Check for directory
 574         if( !(h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
 575                 Log_Warning("VFS", "VFS_OpenChild - Passed handle is not a directory", FD);
 576                 if(Errno)       *Errno = ENOTDIR;
 577                 LEAVE('i', -1);
 578                 return -1;
 579         }
 580
 581         // Find Child
 582         node = h->Node->FindDir(h->Node, Name);
 583         if(!node) {
 584                 if(Errno)       *Errno = ENOENT;
 585                 LEAVE('i', -1);
 586                 return -1;
 587         }
 588
 589         i = 0;
 590         i |= (Mode & VFS_OPENFLAG_EXEC) ? VFS_PERM_EXECUTE : 0;
 591         i |= (Mode & VFS_OPENFLAG_READ) ? VFS_PERM_READ : 0;
 592         i |= (Mode & VFS_OPENFLAG_WRITE) ? VFS_PERM_WRITE : 0;
 593
 594         // Permissions Check
 595         if( !VFS_CheckACL(node, i) ) {
 596                 if(node->Close) node->Close( node );
 597                 Log_Notice("VFS", "VFS_OpenChild - Permissions Failed");
 598                 if(Errno)       *Errno = EACCES;
 599                 LEAVE('i', -1);
 600                 return -1;
 601         }
 602
 603         // Check for a user open
 604         if(Mode & VFS_OPENFLAG_USER)
 605         {
 606                 // Allocate Buffer
 607                 if( MM_GetPhysAddr( (Uint)gaUserHandles ) == 0 )
 608                 {
 609                         Uint    addr, size;
 610                         size = CFGINT(CFG_VFS_MAXFILES) * sizeof(tVFS_Handle);
 611                         for(addr = 0; addr < size; addr += 0x1000)
 612                                 MM_Allocate( (Uint)gaUserHandles + addr );
 613                         memset( gaUserHandles, 0, size );
 614                 }
 615                 // Get a handle
 616                 for(i=0;i<CFGINT(CFG_VFS_MAXFILES);i++)
 617                 {
 618                         if(gaUserHandles[i].Node)       continue;
 619                         gaUserHandles[i].Node = node;
 620                         gaUserHandles[i].Position = 0;
 621                         gaUserHandles[i].Mode = Mode;
 622                         LEAVE('i', i);
 623                         return i;
 624                 }
 625         }
 626         else
 627         {
 628                 // Allocate space if not already
 629                 if( MM_GetPhysAddr( (Uint)gaKernelHandles ) == 0 )
 630                 {
 631                         Uint    addr, size;
 632                         size = MAX_KERNEL_FILES * sizeof(tVFS_Handle);
 633                         for(addr = 0; addr < size; addr += 0x1000)
 634                                 MM_Allocate( (Uint)gaKernelHandles + addr );
 635                         memset( gaKernelHandles, 0, size );
 636                 }
 637                 // Get a handle
 638                 for(i=0;i<MAX_KERNEL_FILES;i++)
 639                 {
 640                         if(gaKernelHandles[i].Node)     continue;
 641                         gaKernelHandles[i].Node = node;
 642                         gaKernelHandles[i].Position = 0;
 643                         gaKernelHandles[i].Mode = Mode;
 644                         LEAVE('x', i|VFS_KERNEL_FLAG);
 645                         return i|VFS_KERNEL_FLAG;
 646                 }
 647         }
 648
 649         Log_Error("VFS", "VFS_OpenChild - Out of handles");
 650         if(Errno)       *Errno = ENFILE;
 651         LEAVE('i', -1);
 652         return -1;
 653 }
 654
 655 /**
 656  * \fn void VFS_Close(int FD)
 657  * \brief Closes an open file handle
 658  */
 659 void VFS_Close(int FD)
 660 {
 661         tVFS_Handle     *h;
 662
 663         // Get handle
 664         h = VFS_GetHandle(FD);
 665         if(h == NULL) {
 666                 Log_Warning("VFS", "Invalid file handle passed to VFS_Close, 0x%x\n", FD);
 667                 return;
 668         }
 669
 670         #if VALIDATE_VFS_FUNCTIPONS
 671         if(h->Node->Close && !MM_GetPhysAddr(h->Node->Close)) {
 672                 Log_Warning("VFS", "Node %p's ->Close method is invalid (%p)",
 673                         h->Node, h->Node->Close);
 674                 return ;
 675         }
 676         #endif
 677
 678         if(h->Node->Close)
 679                 h->Node->Close( h->Node );
 680
 681         h->Node = NULL;
 682 }
 683
 684 /**
 685  * \brief Change current working directory
 686  */
 687 int VFS_ChDir(char *Dest)
 688 {
 689         char    *buf;
 690          int    fd;
 691         tVFS_Handle     *h;
 692
 693         // Create Absolute
 694         buf = VFS_GetAbsPath(Dest);
 695         if(buf == NULL) {
 696                 Log("VFS_ChDir: Path expansion failed");
 697                 return -1;
 698         }
 699
 700         // Check if path exists
 701         fd = VFS_Open(buf, VFS_OPENFLAG_EXEC);
 702         if(fd == -1) {
 703                 Log("VFS_ChDir: Path is invalid");
 704                 return -1;
 705         }
 706
 707         // Get node so we can check for directory
 708         h = VFS_GetHandle(fd);
 709         if( !(h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
 710                 Log("VFS_ChDir: Path is not a directory");
 711                 VFS_Close(fd);
 712                 return -1;
 713         }
 714
 715         // Close file
 716         VFS_Close(fd);
 717
 718         // Free old working directory
 719         if( CFGPTR(CFG_VFS_CWD) )
 720                 free( CFGPTR(CFG_VFS_CWD) );
 721         // Set new
 722         CFGPTR(CFG_VFS_CWD) = buf;
 723
 724         Log("Updated CWD to '%s'", buf);
 725
 726         return 1;
 727 }
 728
 729 /**
 730  * \fn int VFS_ChRoot(char *New)
 731  * \brief Change current root directory
 732  */
 733 int VFS_ChRoot(char *New)
 734 {
 735         char    *buf;
 736          int    fd;
 737         tVFS_Handle     *h;
 738
 739         if(New[0] == '/' && New[1] == '\0')
 740                 return 1;       // What a useless thing to ask!
 741
 742         // Create Absolute
 743         buf = VFS_GetAbsPath(New);
 744         if(buf == NULL) {
 745                 LOG("Path expansion failed");
 746                 return -1;
 747         }
 748
 749         // Check if path exists
 750         fd = VFS_Open(buf, VFS_OPENFLAG_EXEC);
 751         if(fd == -1) {
 752                 LOG("Path is invalid");
 753                 return -1;
 754         }
 755
 756         // Get node so we can check for directory
 757         h = VFS_GetHandle(fd);
 758         if( !(h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
 759                 LOG("Path is not a directory");
 760                 VFS_Close(fd);
 761                 return -1;
 762         }
 763
 764         // Close file
 765         VFS_Close(fd);
 766
 767         // Free old working directory
 768         if( CFGPTR(CFG_VFS_CHROOT) )
 769                 free( CFGPTR(CFG_VFS_CHROOT) );
 770         // Set new
 771         CFGPTR(CFG_VFS_CHROOT) = buf;
 772
 773         LOG("Updated Root to '%s'", buf);
 774
 775         return 1;
 776 }
 777
 778 /**
 779  * \fn tVFS_Handle *VFS_GetHandle(int FD)
 780  * \brief Gets a pointer to the handle information structure
 781  */
 782 tVFS_Handle *VFS_GetHandle(int FD)
 783 {
 784         tVFS_Handle     *h;
 785
 786         //Log_Debug("VFS", "VFS_GetHandle: (FD=0x%x)", FD);
 787
 788         if(FD < 0)      return NULL;
 789
 790         if(FD & VFS_KERNEL_FLAG) {
 791                 FD &= (VFS_KERNEL_FLAG - 1);
 792                 if(FD >= MAX_KERNEL_FILES)      return NULL;
 793                 h = &gaKernelHandles[ FD ];
 794         } else {
 795                 if(FD >= CFGINT(CFG_VFS_MAXFILES))      return NULL;
 796                 h = &gaUserHandles[ FD ];
 797         }
 798
 799         if(h->Node == NULL)     return NULL;
 800         //Log_Debug("VFS", "VFS_GetHandle: RETURN %p", h);
 801         return h;
 802 }
 803
 804 // === EXPORTS ===
 805 EXPORT(VFS_Open);
 806 EXPORT(VFS_Close);