Move webkit/fileapi/file_system_mount_point_provider.h to webkit/browser/fileapi

webkit/fileapi/isolated_context.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef WEBKIT_FILEAPI_ISOLATED_CONTEXT_H_
-#define WEBKIT_FILEAPI_ISOLATED_CONTEXT_H_
-
-#include <map>
-#include <set>
-#include <string>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/files/file_path.h"
-#include "base/lazy_instance.h"
-#include "base/memory/singleton.h"
-#include "base/synchronization/lock.h"
-#include "webkit/fileapi/file_system_types.h"
-#include "webkit/fileapi/mount_points.h"
-#include "webkit/storage/webkit_storage_export.h"
-
-namespace fileapi {
-class FileSystemURL;
-}
-
-namespace fileapi {
-
-// Manages isolated filesystem mount points which have no well-known names
-// and are identified by a string 'filesystem ID', which usually just looks
-// like random value.
-// This type of filesystem can be created on the fly and may go away when it has
-// no references from renderers.
-// Files in an isolated filesystem are registered with corresponding names and
-// identified by a filesystem URL like:
-//
-//   filesystem:<origin>/isolated/<filesystem_id>/<name>/relative/path
-//
-// Some methods of this class are virtual just for mocking.
-//
-class WEBKIT_STORAGE_EXPORT IsolatedContext : public MountPoints {
- public:
-  class WEBKIT_STORAGE_EXPORT FileInfoSet {
-   public:
-    FileInfoSet();
-    ~FileInfoSet();
-
-    // Add the given |path| to the set and populates |registered_name| with
-    // the registered name assigned for the path. |path| needs to be
-    // absolute and should not contain parent references.
-    // Return false if the |path| is not valid and could not be added.
-    bool AddPath(const base::FilePath& path, std::string* registered_name);
-
-    // Add the given |path| with the |name|.
-    // Return false if the |name| is already registered in the set or
-    // is not valid and could not be added.
-    bool AddPathWithName(const base::FilePath& path, const std::string& name);
-
-    const std::set<MountPointInfo>& fileset() const { return fileset_; }
-
-   private:
-    std::set<MountPointInfo> fileset_;
-  };
-
-  // The instance is lazily created per browser process.
-  static IsolatedContext* GetInstance();
-
-  // Returns true if the given filesystem type is managed by IsolatedContext
-  // (i.e. if the given |type| is Isolated or External).
-  // TODO(kinuko): needs a better function name.
-  static bool IsIsolatedType(FileSystemType type);
-
-  // Registers a new isolated filesystem with the given FileInfoSet |files|
-  // and returns the new filesystem_id.  The files are registered with their
-  // register_name as their keys so that later we can resolve the full paths
-  // for the given name.  We only expose the name and the ID for the
-  // newly created filesystem to the renderer for the sake of security.
-  //
-  // The renderer will be sending filesystem requests with a virtual path like
-  // '/<filesystem_id>/<registered_name>/<relative_path_from_the_dropped_path>'
-  // for which we could crack in the browser process by calling
-  // CrackIsolatedPath to get the full path.
-  //
-  // For example: if a dropped file has a path like '/a/b/foo' and we register
-  // the path with the name 'foo' in the newly created filesystem.
-  // Later if the context is asked to crack a virtual path like '/<fsid>/foo'
-  // it can properly return the original path '/a/b/foo' by looking up the
-  // internal mapping.  Similarly if a dropped entry is a directory and its
-  // path is like '/a/b/dir' a virtual path like '/<fsid>/dir/foo' can be
-  // cracked into '/a/b/dir/foo'.
-  //
-  // Note that the path in |fileset| that contains '..' or is not an
-  // absolute path is skipped and is not registered.
-  std::string RegisterDraggedFileSystem(const FileInfoSet& files);
-
-  // Registers a new isolated filesystem for a given |path| of filesystem
-  // |type| filesystem and returns a new filesystem ID.
-  // |path| must be an absolute path which has no parent references ('..').
-  // If |register_name| is non-null and has non-empty string the path is
-  // registered as the given |register_name|, otherwise it is populated
-  // with the name internally assigned to the path.
-  std::string RegisterFileSystemForPath(FileSystemType type,
-                                        const base::FilePath& path,
-                                        std::string* register_name);
-
-  // Revokes all filesystem(s) registered for the given path.
-  // This is assumed to be called when the registered path becomes
-  // globally invalid, e.g. when a device for the path is detached.
-  //
-  // Note that this revokes the filesystem no matter how many references it has.
-  // It is ok to call this for the path that has no associated filesystems.
-  // Note that this only works for the filesystems registered by
-  // |RegisterFileSystemForPath|.
-  void RevokeFileSystemByPath(const base::FilePath& path);
-
-  // Adds a reference to a filesystem specified by the given filesystem_id.
-  void AddReference(const std::string& filesystem_id);
-
-  // Removes a reference to a filesystem specified by the given filesystem_id.
-  // If the reference count reaches 0 the isolated context gets destroyed.
-  // It is OK to call this on the filesystem that has been already deleted
-  // (e.g. by RevokeFileSystemByPath).
-  void RemoveReference(const std::string& filesystem_id);
-
-  // Returns a set of dragged MountPointInfos registered for the
-  // |filesystem_id|.
-  // The filesystem_id must be pointing to a dragged file system
-  // (i.e. must be the one registered by RegisterDraggedFileSystem).
-  // Returns false if the |filesystem_id| is not valid.
-  bool GetDraggedFileInfo(const std::string& filesystem_id,
-                          std::vector<MountPointInfo>* files) const;
-
-  // MountPoints overrides.
-  virtual bool HandlesFileSystemMountType(FileSystemType type) const OVERRIDE;
-  virtual bool RevokeFileSystem(const std::string& filesystem_id) OVERRIDE;
-  virtual bool GetRegisteredPath(const std::string& filesystem_id,
-                                 base::FilePath* path) const OVERRIDE;
-  virtual bool CrackVirtualPath(const base::FilePath& virtual_path,
-                                std::string* filesystem_id,
-                                FileSystemType* type,
-                                base::FilePath* path) const OVERRIDE;
-  virtual FileSystemURL CrackURL(const GURL& url) const OVERRIDE;
-  virtual FileSystemURL CreateCrackedFileSystemURL(
-      const GURL& origin,
-      FileSystemType type,
-      const base::FilePath& path) const OVERRIDE;
-
-  // Returns the virtual root path that looks like /<filesystem_id>.
-  base::FilePath CreateVirtualRootPath(const std::string& filesystem_id) const;
-
- private:
-  friend struct base::DefaultLazyInstanceTraits<IsolatedContext>;
-
-  // Represents each file system instance (defined in the .cc).
-  class Instance;
-
-  typedef std::map<std::string, Instance*> IDToInstance;
-
-  // Reverse map from registered path to IDs.
-  typedef std::map<base::FilePath, std::set<std::string> > PathToID;
-
-  // Obtain an instance of this class via GetInstance().
-  IsolatedContext();
-  virtual ~IsolatedContext();
-
-  // MountPoints overrides.
-  virtual FileSystemURL CrackFileSystemURL(
-      const FileSystemURL& url) const OVERRIDE;
-
-  // Unregisters a file system of given |filesystem_id|. Must be called with
-  // lock_ held.  Returns true if the file system is unregistered.
-  bool UnregisterFileSystem(const std::string& filesystem_id);
-
-  // Returns a new filesystem_id.  Called with lock.
-  std::string GetNewFileSystemId() const;
-
-  // This lock needs to be obtained when accessing the instance_map_.
-  mutable base::Lock lock_;
-
-  IDToInstance instance_map_;
-  PathToID path_to_id_map_;
-
-  DISALLOW_COPY_AND_ASSIGN(IsolatedContext);
-};
-
-}  // namespace fileapi
-
-#endif  // WEBKIT_FILEAPI_ISOLATED_CONTEXT_H_