3 * - Open, Close and ChDir
13 #define OPEN_MOUNT_ROOT 1
14 #define MAX_PATH_SLASHES 256
15 #define MAX_NESTED_LINKS 4
16 #define MAX_PATH_LEN 255
19 extern tVFS_Mount *gVFS_RootMount;
20 extern int VFS_AllocHandle(int bIsUser, tVFS_Node *Node, int Mode);
21 extern tVFS_Node *VFS_MemFile_Create(const char *Path);
24 int VFS_int_CreateHandle( tVFS_Node *Node, tVFS_Mount *Mount, int Mode );
28 * \fn char *VFS_GetAbsPath(const char *Path)
29 * \brief Create an absolute path from a relative one
31 char *VFS_GetAbsPath(const char *Path)
34 int pathLen = strlen(Path);
35 char *pathComps[MAX_PATH_SLASHES];
39 const char *chroot = *Threads_GetChroot();
41 const char *cwd = *Threads_GetCWD();
48 ret = malloc(strlen(Path)+1);
50 Log_Warning("VFS", "VFS_GetAbsPath: malloc() returned NULL");
61 chrootLen = strlen(chroot);
62 // Trim trailing slash off chroot
63 if( chrootLen && chroot[chrootLen - 1] == '/' )
66 // Check if the path is already absolute
68 ret = malloc(chrootLen + pathLen + 1);
70 Log_Warning("VFS", "VFS_GetAbsPath: malloc() returned NULL");
73 strcpy(ret + chrootLen, Path);
83 // Prepend the current directory
84 ret = malloc(chrootLen + cwdLen + 1 + pathLen + 1 );
85 strcpy(ret+chrootLen, cwd);
87 strcpy(ret+chrootLen+cwdLen+1, Path);
88 //Log("ret = '%s'", ret);
92 pathComps[iPos++] = tmpStr = ret+chrootLen+1;
97 pathComps[iPos++] = tmpStr;
98 if(iPos == MAX_PATH_SLASHES) {
99 LOG("Path '%s' has too many elements", Path);
106 pathComps[iPos] = NULL;
110 while(pathComps[iPos])
112 tmpStr = pathComps[iPos];
113 // Always Increment iPos
116 if(tmpStr[0] == '.' && tmpStr[1] == '.' && (tmpStr[2] == '/' || tmpStr[2] == '\0') )
123 if(tmpStr[0] == '.' && (tmpStr[1] == '/' || tmpStr[1] == '\0') )
128 if(tmpStr[0] == '/' || tmpStr[0] == '\0')
134 pathComps[iPos2] = tmpStr;
137 pathComps[iPos2] = NULL;
140 iPos2 = chrootLen + 1; iPos = 0;
142 while(pathComps[iPos])
144 tmpStr = pathComps[iPos];
145 while(*tmpStr && *tmpStr != '/')
147 ret[iPos2++] = *tmpStr;
158 // Prepend the chroot
160 memcpy( ret, chroot, chrootLen );
163 // Log_Debug("VFS", "VFS_GetAbsPath: RETURN '%s'", ret);
168 * \fn char *VFS_ParsePath(const char *Path, char **TruePath)
169 * \brief Parses a path, resolving sysmlinks and applying permissions
171 tVFS_Node *VFS_ParsePath(const char *Path, char **TruePath, tVFS_Mount **MountPoint)
173 tVFS_Mount *mnt, *longestMount;
174 int cmp, retLength = 0;
176 int iNestedLinks = 0;
177 tVFS_Node *curNode, *tmpNode;
179 char path_buffer[MAX_PATH_LEN+1];
181 ENTER("sPath pTruePath", Path, TruePath);
184 if(Threads_GetUID() == 0 && Path[0] == '$') {
186 *TruePath = malloc(strlen(Path)+1);
187 strcpy(*TruePath, Path);
189 curNode = VFS_MemFile_Create(Path);
198 // For root we always fast return
199 if(Path[0] == '/' && Path[1] == '\0') {
201 *TruePath = malloc( gVFS_RootMount->MountPointLen+1 );
202 strcpy(*TruePath, gVFS_RootMount->MountPoint);
204 if(MountPoint) *MountPoint = gVFS_RootMount;
205 LEAVE('p', gVFS_RootMount->RootNode);
206 return gVFS_RootMount->RootNode;
209 // Check if there is anything mounted
211 Log_Error("VFS", "VFS_ParsePath - No filesystems mounted");
216 longestMount = gVFS_RootMount;
217 RWLock_AcquireRead( &glVFS_MountList );
218 for(mnt = gVFS_Mounts; mnt; mnt = mnt->Next)
221 if( Path[mnt->MountPointLen] != '/' && Path[mnt->MountPointLen] != '\0')
223 // Length Check - If the length is smaller than the longest match sofar
224 if(mnt->MountPointLen < longestMount->MountPointLen) continue;
226 cmp = strncmp(Path, mnt->MountPoint, mnt->MountPointLen);
227 // Not a match, continue
228 if(cmp != 0) continue;
231 // Fast Break - Request Mount Root
232 if(Path[mnt->MountPointLen] == '\0') {
234 *TruePath = malloc( mnt->MountPointLen+1 );
235 strcpy(*TruePath, mnt->MountPoint);
239 RWLock_Release( &glVFS_MountList );
240 LOG("Mount %p root", mnt);
241 LEAVE('p', mnt->RootNode);
242 return mnt->RootNode;
247 longestMount->OpenHandleCount ++; // Increment assuimg it worked
248 RWLock_Release( &glVFS_MountList );
250 // Save to shorter variable
253 LOG("mnt = {MountPoint:\"%s\"}", mnt->MountPoint);
258 // Assumes that the resultant path (here) will not be > strlen(Path) + 1
259 *TruePath = malloc( strlen(Path) + 1 );
260 strcpy(*TruePath, mnt->MountPoint);
261 retLength = mnt->MountPointLen;
264 curNode = mnt->RootNode;
265 curNode->ReferenceCount ++;
267 ofs = mnt->MountPointLen+1;
268 for(; (nextSlash = strpos(&Path[ofs], '/')) != -1; ofs += nextSlash + 1)
270 char pathEle[nextSlash+1];
273 if(nextSlash == 0) continue;
275 memcpy(pathEle, &Path[ofs], nextSlash);
276 pathEle[nextSlash] = 0;
278 // Check permissions on root of filesystem
279 if( !VFS_CheckACL(curNode, VFS_PERM_EXECUTE) ) {
280 LOG("Permissions failure on '%s'", Path);
284 // Check if the node has a FindDir method
285 if( !curNode->Type->FindDir )
287 LOG("Finddir failure on '%s'", Path);
290 LOG("FindDir{=%p}(%p, '%s')", curNode->Type->FindDir, curNode, pathEle);
292 tmpNode = curNode->Type->FindDir(curNode, pathEle);
293 LOG("tmpNode = %p", tmpNode);
294 _CloseNode( curNode );
299 LOG("Node '%s' not found in dir '%s'", pathEle, Path);
303 // Handle Symbolic Links
304 if(curNode->Flags & VFS_FFLAG_SYMLINK) {
309 if(!curNode->Type || !curNode->Type->Read) {
310 Log_Warning("VFS", "VFS_ParsePath - Read of symlink node %p'%s' is NULL",
315 if(iNestedLinks > MAX_NESTED_LINKS) {
316 Log_Notice("VFS", "VFS_ParsePath - Nested link limit exceeded");
320 // Parse Symlink Path
321 // - Just update the path variable and restart the function
322 // > Count nested symlinks and limit to some value (counteracts loops)
324 int remlen = strlen(Path) - (ofs + nextSlash);
325 if( curNode->Size + remlen > MAX_PATH_LEN ) {
326 Log_Warning("VFS", "VFS_ParsePath - Symlinked path too long");
329 curNode->Type->Read( curNode, 0, curNode->Size, path_buffer );
330 path_buffer[ curNode->Size ] = '\0';
331 LOG("path_buffer = '%s'", path_buffer);
332 strcat(path_buffer, Path + ofs+nextSlash);
335 // Log_Debug("VFS", "VFS_ParsePath: Symlink translated to '%s'", Path);
340 LOG("Symlink -> '%s', restart", Path);
341 mnt->OpenHandleCount --; // Not in this mountpoint
345 // Handle Non-Directories
346 if( !(curNode->Flags & VFS_FFLAG_DIRECTORY) )
348 Log_Warning("VFS", "VFS_ParsePath - Path segment is not a directory");
352 // Check if path needs extending
353 if(!TruePath) continue;
355 // Increase buffer space
356 tmp = realloc( *TruePath, retLength + strlen(pathEle) + 1 + 1 );
357 // Check if allocation succeeded
359 Log_Warning("VFS", "VFS_ParsePath - Unable to reallocate true path buffer");
364 (*TruePath)[retLength] = '/';
365 strcpy(*TruePath+retLength+1, pathEle);
367 LOG("*TruePath = '%s'", *TruePath);
370 retLength += nextSlash + 1;
373 // Check final finddir call
374 if( !curNode->Type || !curNode->Type->FindDir ) {
375 Log_Warning("VFS", "VFS_ParsePath - FindDir doesn't exist for element of '%s'", Path);
380 LOG("FindDir(%p, '%s')", curNode, &Path[ofs]);
381 tmpNode = curNode->Type->FindDir(curNode, &Path[ofs]);
382 LOG("tmpNode = %p", tmpNode);
383 // Check if file was found
385 LOG("Node '%s' not found in dir '%s'", &Path[ofs], Path);
388 _CloseNode( curNode );
392 // Increase buffer space
393 tmp = realloc(*TruePath, retLength + strlen(&Path[ofs]) + 1 + 1);
394 // Check if allocation succeeded
396 Log_Warning("VFS", "VFS_ParsePath - Unable to reallocate true path buffer");
401 (*TruePath)[retLength] = '/';
402 strcpy(*TruePath + retLength + 1, &Path[ofs]);
404 //retLength += strlen(tmpNode->Name) + 1;
411 // Leave the mointpoint's count increased
417 _CloseNode( curNode );
419 if(TruePath && *TruePath) {
423 // Open failed, so decrement the open handle count
424 mnt->OpenHandleCount --;
431 * \brief Create and return a handle number for the given node and mode
433 int VFS_int_CreateHandle( tVFS_Node *Node, tVFS_Mount *Mount, int Mode )
437 ENTER("pNode pMount xMode", Node, Mount, Mode);
440 i |= (Mode & VFS_OPENFLAG_EXEC) ? VFS_PERM_EXECUTE : 0;
441 i |= (Mode & VFS_OPENFLAG_READ) ? VFS_PERM_READ : 0;
442 i |= (Mode & VFS_OPENFLAG_WRITE) ? VFS_PERM_WRITE : 0;
447 if( !VFS_CheckACL(Node, i) ) {
449 Log_Log("VFS", "VFS_int_CreateHandle: Permissions Failed");
454 i = VFS_AllocHandle( !!(Mode & VFS_OPENFLAG_USER), Node, Mode );
456 Log_Notice("VFS", "VFS_int_CreateHandle: Out of handles");
461 VFS_GetHandle(i)->Mount = Mount;
467 * \fn int VFS_Open(const char *Path, Uint Mode)
470 int VFS_Open(const char *Path, Uint Flags)
472 return VFS_OpenEx(Path, Flags, 0);
475 int VFS_OpenEx(const char *Path, Uint Flags, Uint Mode)
481 ENTER("sPath xFlags oMode", Path, Flags);
484 absPath = VFS_GetAbsPath(Path);
485 if(absPath == NULL) {
486 Log_Warning("VFS", "VFS_Open: Path expansion failed '%s'", Path);
489 LOG("absPath = \"%s\"", absPath);
491 // Parse path and get mount point
492 node = VFS_ParsePath(absPath, NULL, &mnt);
494 // Create file if requested and it doesn't exist
495 if( !node && (Flags & VFS_OPENFLAG_CREATE) )
497 // TODO: Translate `Mode` into ACL and node flags
498 // Get parent, create node
499 if( VFS_MkNod(absPath, 0) ) {
503 node = VFS_ParsePath(absPath, NULL, &mnt);
506 // Free generated path
512 LOG("Cannot find node");
517 // Check for symlinks
518 if( !(Flags & VFS_OPENFLAG_NOLINK) && (node->Flags & VFS_FFLAG_SYMLINK) )
520 char tmppath[node->Size+1];
521 if( node->Size > MAX_PATH_LEN ) {
522 Log_Warning("VFS", "VFS_Open - Symlink is too long (%i)", node->Size);
525 if( !node->Type || !node->Type->Read ) {
526 Log_Warning("VFS", "VFS_Open - No read method on symlink");
529 // Read symlink's path
530 node->Type->Read( node, 0, node->Size, tmppath );
531 tmppath[ node->Size ] = '\0';
534 node = VFS_ParsePath(tmppath, NULL, &mnt);
536 LOG("Cannot find symlink target node (%s)", tmppath);
542 LEAVE_RET('x', VFS_int_CreateHandle(node, mnt, Flags));
547 * \brief Open a file from an open directory
549 int VFS_OpenChild(int FD, const char *Name, Uint Mode)
554 ENTER("xFD sName xMode", FD, Name, Mode);
557 h = VFS_GetHandle(FD);
559 Log_Warning("VFS", "VFS_OpenChild - Invalid file handle 0x%x", FD);
564 // Check for directory
565 if( !(h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
566 Log_Warning("VFS", "VFS_OpenChild - Passed handle is not a directory");
572 if( !h->Node->Type || !h->Node->Type->FindDir ) {
573 Log_Error("VFS", "VFS_OpenChild - Node does not have a type/is missing FindDir");
579 node = h->Node->Type->FindDir(h->Node, Name);
585 // Increment open handle count, no problems with the mount going away as `h` is already open on it
586 h->Mount->OpenHandleCount ++;
588 LEAVE_RET('x', VFS_int_CreateHandle(node, h->Mount, Mode));
591 int VFS_OpenInode(Uint32 Mount, Uint64 Inode, int Mode)
596 ENTER("iMount XInode xMode", Mount, Inode, Mode);
599 mnt = VFS_GetMountByIdent(Mount);
601 LOG("Mount point ident invalid");
606 // Does the filesystem support this?
607 if( !mnt->Filesystem->GetNodeFromINode ) {
608 LOG("Filesystem does not support inode accesses");
614 node = mnt->Filesystem->GetNodeFromINode(mnt->RootNode, Inode);
616 LOG("Unable to find inode");
621 LEAVE_RET('x', VFS_int_CreateHandle(node, mnt, Mode));
625 * \fn void VFS_Close(int FD)
626 * \brief Closes an open file handle
628 void VFS_Close(int FD)
633 h = VFS_GetHandle(FD);
635 Log_Warning("VFS", "Invalid file handle passed to VFS_Close, 0x%x", FD);
639 #if VALIDATE_VFS_FUNCTIPONS
640 if(h->Node->Close && !MM_GetPhysAddr(h->Node->Close)) {
641 Log_Warning("VFS", "Node %p's ->Close method is invalid (%p)",
642 h->Node, h->Node->Close);
649 h->Mount->OpenHandleCount --;
655 * \brief Change current working directory
657 int VFS_ChDir(const char *Dest)
664 buf = VFS_GetAbsPath(Dest);
666 Log_Notice("VFS", "VFS_ChDir: Path expansion failed");
670 // Check if path exists
671 fd = VFS_Open(buf, VFS_OPENFLAG_EXEC);
673 Log_Notice("VFS", "VFS_ChDir: Path is invalid");
677 // Get node so we can check for directory
678 h = VFS_GetHandle(fd);
679 if( !(h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
680 Log("VFS_ChDir: Path is not a directory");
689 char **cwdptr = Threads_GetCWD();
690 // Free old working directory
691 if( *cwdptr ) free( *cwdptr );
696 Log("Updated CWD to '%s'", buf);
702 * \fn int VFS_ChRoot(char *New)
703 * \brief Change current root directory
705 int VFS_ChRoot(const char *New)
711 if(New[0] == '/' && New[1] == '\0')
712 return 1; // What a useless thing to ask!
715 buf = VFS_GetAbsPath(New);
717 LOG("Path expansion failed");
721 // Check if path exists
722 fd = VFS_Open(buf, VFS_OPENFLAG_EXEC);
724 LOG("Path is invalid");
728 // Get node so we can check for directory
729 h = VFS_GetHandle(fd);
730 if( !(h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
731 LOG("Path is not a directory");
741 char **chroot_ptr = Threads_GetChroot();
742 if( *chroot_ptr ) free( *chroot_ptr );
746 LOG("Updated Root to '%s'", buf);