/// <summary>
/// Performs a path lookup obeying to the passed flags.
/// </summary>
/// <param name="rootDirectory">The root directory.</param>
/// <param name="path">The path to resolve.</param>
/// <param name="flags">Controls aspects of the path lookup process.</param>
/// <returns>The directory entry of the resolved path.</returns>
/// <exception cref="System.Security.SecurityException">The caller does not have access to the path or a component. For example the caller does not have the right to traverse the path.</exception>
/// <exception cref="System.IO.PathTooLongException">The path is too long to traverse. This can be the result of circular symbolic links in the path.</exception>
/// <exception cref="System.IO.FileNotFoundException">The file or folder path was not found. This exception can be prevented by specifying PathResolutionFlags.DoNotThrowNotFoundException.</exception>
/// <exception cref="System.IO.DirectoryNotFoundException">A path component was not found. This exception can be prevented by specifying PathResolutionFlags.DoNotThrowNotFoundException.</exception>
/// <remarks>
/// This call my result in other exceptions not specified in the above list. Other exceptions can be thrown by IVfsNode implementations, which are visited during the traversal
/// process. For example a network file system node may throw an exception, if the server is unreachable.
/// </remarks>
public static DirectoryEntry Resolve(DirectoryEntry rootDirectory, ref string path, PathResolutionFlags flags)
{
// FIXME: Get the root from the thread execution block
DirectoryEntry current = rootDirectory;
PathResolver resolver = new PathResolver(rootDirectory, current);
return(resolver.Resolve(ref path, flags));
}
/// <summary>
/// Performs a standard path lookup.
/// </summary>
/// <param name="rootDirectory">The root directory.</param>
/// <param name="path">The path to resolve.</param>
/// <returns>The directory entry of the resolved path.</returns>
/// <exception cref="System.Security.SecurityException">The caller does not have access to the path or a component. For example the caller does not have the right to traverse the path.</exception>
/// <exception cref="System.IO.PathTooLongException">The path is too long to traverse. This can be the result of circular symbolic links in the path.</exception>
/// <exception cref="System.IO.FileNotFoundException">The file or folder path not found.</exception>
/// <exception cref="System.IO.DirectoryNotFoundException">A path component was not found.</exception>
/// <remarks>
/// This call my result in other exceptions not specified in the above list. Other exceptions can be thrown by IVfsNode implementations, which are visited during the traversal
/// process. For example a network file system node may throw an exception, if the server is unreachable.
/// </remarks>
public static DirectoryEntry Resolve(DirectoryEntry rootDirectory, ref string path)
{
// FIXME: Remove the root argument. The filesystem root should be unique for a process as part of a security model similar to jails, e.g. give apps from
// untrusted sources their private filesystem regions.
// FIXME: Get the root from the thread execution block
DirectoryEntry current = rootDirectory;
PathResolver resolver = new PathResolver(rootDirectory, current);
return(resolver.Resolve(ref path, PathResolutionFlags.None));
}
/// <summary>
/// Checks if the caller has access to the inode
/// </summary>
/// <param name="path">The resource to check permissions for.</param>
/// <returns>True if the requested access mode combination is available to the immediate caller. If any one requested access mode is not available, the result is false.</returns>
public static bool Access(string path, AccessMode mode)
{
DirectoryEntry entry = PathResolver.Resolve(rootNode, ref path, PathResolutionFlags.DoNotThrowNotFoundException);
if (null != entry)
{
return(AccessCheck.Perform(entry, mode, AccessCheckFlags.NoThrow));
}
return(false);
}
/// <summary>
/// Deletes the named node from the filesystem.
/// </summary>
/// <param name="path">The path, which identifies a node.</param>
public static void Delete(string path)
{
DirectoryEntry entry = PathResolver.Resolve(rootNode, ref path, PathResolutionFlags.DoNotThrowNotFoundException);
if (null != entry)
{
AccessCheck.Perform(entry, AccessMode.Delete, AccessCheckFlags.None);
//entry.Node.Delete();
entry.Parent.Node.Delete(entry.Node, entry);
entry.Release();
}
}
public static object Open(string path, FileAccess access, FileShare share)
{
DirectoryEntry entry = PathResolver.Resolve(rootNode, ref path);
/* HINT:
*
* 1. Do we really need to pass the FileShare flags down to the inode?
* 2. Shouldn't we have some sort of lock deamon governing shared access?
*
* Ansers:
* 1. Yes.
* 2. Yes and no. A lock deamon would only work for local filesystems. For imported
* ones we need to notify the server of the sharing lock anyway, so that the IVfsNode
* (acting as a client to the server) is the best place to do it without giving the
* lock deamon knowledge of all file sharing protocols (afp, smb, ftp, name it.)
* 3. The inode may reject the file sharing requests. We do want to represent devices
* and sync objects in the VFS, which means *they* need to decide if the flags are
* applicable.
*
*/
// FIXME: Perform access checks on the DirectoryEntry/IVfsNode.
AccessMode modeFlags = AccessMode.Exists;
switch (access)
{
case FileAccess.Read:
modeFlags = AccessMode.Read;
break;
case FileAccess.Write:
modeFlags = AccessMode.Write;
break;
case FileAccess.ReadWrite:
modeFlags = AccessMode.Read | AccessMode.Write;
break;
}
AccessCheck.Perform(entry, modeFlags, AccessCheckFlags.None);
if (entry == null)
{
SharpOS.Kernel.ADC.TextMode.WriteLine("VirtualFileSystem.Open.4a");
}
if (entry.Node == null)
{
SharpOS.Kernel.ADC.TextMode.WriteLine("VirtualFileSystem.Open.4b");
}
return(entry.Node.Open(access, share));
}
/// <summary>
/// Creates a new node in the (virtual) filesystem.
/// </summary>
/// <param name="path">The path to create.</param>
/// <param name="type">The type of the node to create.</param>
/// <param name="settings">Settings used to initialize the node.</param>
/// <param name="access">Requests the specified access modes on the created object.</param>
/// <param name="share">Requests the specified sharing settings on the object.</param>
/// <returns>The created filesystem object.</returns>
/// <remarks>
/// This function creates new nodes in the virtual filesystem. In contrast to *nix this call
/// creates all node types, e.g. files, directories, devices and more. Specific types may
/// require additional settings, which are specified in a settings object passed as the third
/// parameter.
/// </remarks>
public static object Create(string path, VfsNodeType type, object settings, FileAccess access, FileShare share)
{
// Retrieve the parent directory
DirectoryEntry parent = PathResolver.Resolve(rootNode, ref path, PathResolutionFlags.RetrieveParent);
// Check if the caller has write access in the directory
AccessCheck.Perform(parent, AccessMode.Write, AccessCheckFlags.None);
// Yes, we do have write access. Create the new vfs node
IVfsNode node = parent.Node.Create(path, type, settings);
// FIXME: Assert(null != node);
DirectoryEntry entry = DirectoryEntry.Allocate(parent, path, node);
// FIXME: Fix the permissions for this call. *nix does this using its bitmasks, Win32 through its huge CreateFile API.
return(node.Open(access, share));
}
/// <summary>
/// Mounts a new file system.
/// </summary>
/// <param name="source">The source of the filesystem. This is usually a device name, but can also be another directory.</param>
/// <param name="target">The path including the name of the mount point, where to mount the new filesystem.</param>
public static void Mount(string source, string target)
{
// Retrieve the parent directory of the mount
DirectoryEntry parent = PathResolver.Resolve(rootNode, ref target, PathResolutionFlags.RetrieveParent);
if (parent == null)
{
throw new System.ArgumentException();
}
IFileSystem root = FileSystemFactory.CreateFileSystem(source);
if (root == null)
{
throw new System.ArgumentException();
}
PathSplitter path = new PathSplitter(target);
DirectoryEntry.Allocate(parent, path.Last, root.Root);
}
/// <summary>
/// Performs a standard path lookup.
/// </summary>
/// <param name="rootDirectory">The root directory.</param>
/// <param name="path">The path to resolve.</param>
/// <returns>The directory entry of the resolved path.</returns>
/// <exception cref="System.Security.SecurityException">The caller does not have access to the path or a component. For example the caller does not have the right to traverse the path.</exception>
/// <exception cref="System.IO.PathTooLongException">The path is too long to traverse. This can be the result of circular symbolic links in the path.</exception>
/// <exception cref="System.IO.FileNotFoundException">The file or folder path not found.</exception>
/// <exception cref="System.IO.DirectoryNotFoundException">A path component was not found.</exception>
/// <remarks>
/// This call my result in other exceptions not specified in the above list. Other exceptions can be thrown by IVfsNode implementations, which are visited during the traversal
/// process. For example a network file system node may throw an exception, if the server is unreachable.
/// </remarks>
public static DirectoryEntry Resolve (DirectoryEntry rootDirectory, ref string path)
{
// FIXME: Remove the root argument. The filesystem root should be unique for a process as part of a security model similar to jails, e.g. give apps from
// untrusted sources their private filesystem regions.
// FIXME: Get the root from the thread execution block
DirectoryEntry current = rootDirectory;
PathResolver resolver = new PathResolver (rootDirectory, current);
return resolver.Resolve (ref path, PathResolutionFlags.None);
}
/// <summary>
/// Performs a path lookup obeying to the passed flags.
/// </summary>
/// <param name="rootDirectory">The root directory.</param>
/// <param name="path">The path to resolve.</param>
/// <param name="flags">Controls aspects of the path lookup process.</param>
/// <returns>The directory entry of the resolved path.</returns>
/// <exception cref="System.Security.SecurityException">The caller does not have access to the path or a component. For example the caller does not have the right to traverse the path.</exception>
/// <exception cref="System.IO.PathTooLongException">The path is too long to traverse. This can be the result of circular symbolic links in the path.</exception>
/// <exception cref="System.IO.FileNotFoundException">The file or folder path was not found. This exception can be prevented by specifying PathResolutionFlags.DoNotThrowNotFoundException.</exception>
/// <exception cref="System.IO.DirectoryNotFoundException">A path component was not found. This exception can be prevented by specifying PathResolutionFlags.DoNotThrowNotFoundException.</exception>
/// <remarks>
/// This call my result in other exceptions not specified in the above list. Other exceptions can be thrown by IVfsNode implementations, which are visited during the traversal
/// process. For example a network file system node may throw an exception, if the server is unreachable.
/// </remarks>
public static DirectoryEntry Resolve (DirectoryEntry rootDirectory, ref string path, PathResolutionFlags flags)
{
// FIXME: Get the root from the thread execution block
DirectoryEntry current = rootDirectory;
PathResolver resolver = new PathResolver (rootDirectory, current);
return resolver.Resolve (ref path, flags);
}
/// <summary>
/// Changes the current directory in the thread execution block.
/// </summary>
/// <param name="path">The path to change to. This path may be relative or absolute.</param>
/// <
public static void ChangeDirectory(string path)
{
DirectoryEntry entry = PathResolver.Resolve(rootNode, ref path);
// FIXME: Set the current directory in the thread execution block
}
