FileAPI: Split recursive remove into multiple async tasks

webkit/fileapi/local_file_system_operation.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_LOCAL_FILE_SYSTEM_OPERATION_H_
 #define WEBKIT_FILEAPI_LOCAL_FILE_SYSTEM_OPERATION_H_
 
 #include <vector>
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "webkit/fileapi/file_system_file_util.h"
 #include "webkit/fileapi/file_system_operation.h"
 #include "webkit/fileapi/file_system_operation_context.h"
 #include "webkit/fileapi/file_system_url.h"
 #include "webkit/fileapi/file_writer_delegate.h"
 #include "webkit/quota/quota_types.h"
 #include "webkit/storage/webkit_storage_export.h"
 
 namespace chromeos {
 class CrosMountPointProvider;
 }
 
 namespace fileapi {
 
 class FileSystemContext;
+class RemoveOperationDelegate;
 
 // FileSystemOperation implementation for local file systems.
 class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
     : public NON_EXPORTED_BASE(FileSystemOperation) {
  public:
   virtual ~LocalFileSystemOperation();
 
   // FileSystemOperation overrides.
   virtual void CreateFile(const FileSystemURL& url,
                           bool exclusive,
@@ skipping 33 matching lines @@
                         int file_flags,
                         base::ProcessHandle peer_handle,
                         const OpenFileCallback& callback) OVERRIDE;
   virtual void NotifyCloseFile(const FileSystemURL& url) OVERRIDE;
   virtual void Cancel(const StatusCallback& cancel_callback) OVERRIDE;
   virtual LocalFileSystemOperation* AsLocalFileSystemOperation() OVERRIDE;
   virtual void CreateSnapshotFile(
       const FileSystemURL& path,
       const SnapshotFileCallback& callback) OVERRIDE;
 
+  // Copies in a single file from a different filesystem.
+  //
+  // This returns:
+  // - PLATFORM_FILE_ERROR_NOT_FOUND if |src_file_path|
+  //   or the parent directory of |dest_url| does not exist.
+  // - PLATFORM_FILE_ERROR_INVALID_OPERATION if |dest_url| exists and
+  //   is not a file.
+  // - PLATFORM_FILE_ERROR_FAILED if |dest_url| does not exist and
+  //   its parent path is a file.
+  //
   void CopyInForeignFile(const FilePath& src_local_disk_path,
                          const FileSystemURL& dest_url,
                          const StatusCallback& callback);
 
+  // Removes a single file.
+  //
+  // This returns:
+  // - PLATFORM_FILE_ERROR_NOT_FOUND if |url| does not exist.
+  // - PLATFORM_FILE_ERROR_NOT_A_FILE if |url| is not a file.
+  //
+  void RemoveFile(const FileSystemURL& url,
+                  const StatusCallback& callback);
+
+  // Removes a single empty directory.
+  //
+  // This returns:
+  // - PLATFORM_FILE_ERROR_NOT_FOUND if |url| does not exist.
+  // - PLATFORM_FILE_ERROR_NOT_A_DIRECTORY if |url| is not a directory.
+  // - PLATFORM_FILE_ERROR_NOT_EMPTY if |url| is not empty.
+  //
+  void RemoveDirectory(const FileSystemURL& url,
+                       const StatusCallback& callback);
+
   // Synchronously gets the platform path for the given |url|.
   void SyncGetPlatformPath(const FileSystemURL& url, FilePath* platform_path);
 
  private:
   class ScopedUpdateNotifier;
 
   enum SetUpMode {
     SETUP_FOR_READ,
     SETUP_FOR_WRITE,
     SETUP_FOR_CREATE,
   };
 
   // Only MountPointProviders or testing class can create a
   // new operation directly.
   friend class FileSystemTestHelper;
   friend class IsolatedMountPointProvider;
   friend class SandboxMountPointProvider;
   friend class TestMountPointProvider;
   friend class chromeos::CrosMountPointProvider;
 
   friend class LocalFileSystemOperationTest;
   friend class LocalFileSystemOperationWriteTest;
   friend class FileWriterDelegateTest;
   friend class FileSystemQuotaTest;
   friend class LocalFileSystemTestOriginHelper;
 
+  friend class RemoveOperationDelegate;
   friend class SyncableFileSystemOperation;
 
   LocalFileSystemOperation(
       FileSystemContext* file_system_context,
       scoped_ptr<FileSystemOperationContext> operation_context);
 
   FileSystemContext* file_system_context() const {
     return file_system_context_;
   }
 
   FileSystemOperationContext* operation_context() const {
+    if (overriding_operation_context_)
+      return overriding_operation_context_;
     return operation_context_.get();
   }
 
   // Queries the quota and usage and then runs the given |task|.
   // If an error occurs during the quota query it runs |error_callback| instead.
   void GetUsageAndQuotaThenRunTask(
       const FileSystemURL& url,
       const base::Closure& task,
       const base::Closure& error_callback);
 
@@ skipping 91 matching lines @@
   // Checks the validity of a given |url| and populates |file_util| for |mode|.
   base::PlatformFileError SetUp(
       const FileSystemURL& url,
       FileSystemFileUtil** file_util,
       SetUpMode mode);
 
   // Used only for internal assertions.
   // Returns false if there's another inflight pending operation.
   bool SetPendingOperationType(OperationType type);
 
+  // Overrides this operation's operation context by given |context|.
+  // This operation won't own |context| and the |context| needs to outlive
+  // this operation.
+  //
+  // Called only from operation delegates when they create sub-operations
+  // for performing a recursive operation.
+  void set_overriding_operation_context(FileSystemOperationContext* context) {
+    overriding_operation_context_ = context;
+  }
+
   scoped_refptr<FileSystemContext> file_system_context_;
 
   scoped_ptr<FileSystemOperationContext> operation_context_;
   FileSystemFileUtil* src_util_;  // Not owned.
   FileSystemFileUtil* dest_util_;  // Not owned.
 
+  FileSystemOperationContext* overriding_operation_context_;
+
   // Indicates if this operation is for cross filesystem operation or not.
   // TODO(kinuko): This should be cleaned up.
   bool is_cross_operation_;
 
   // This is set before any write operations to dispatch
   // FileUpdateObserver::StartUpdate and FileUpdateObserver::EndUpdate.
   ScopedVector<ScopedUpdateNotifier> scoped_update_notifiers_;
 
   // These are all used only by Write().
   friend class FileWriterDelegate;
   scoped_ptr<FileWriterDelegate> file_writer_delegate_;
 
+  scoped_ptr<RemoveOperationDelegate> remove_operation_delegate_;
+
   // write_callback is kept in this class for so that we can dispatch it when
   // the operation is cancelled. calcel_callback is kept for canceling a
   // Truncate() operation. We can't actually stop Truncate in another thread;
   // after it resumed from the working thread, cancellation takes place.
   WriteCallback write_callback_;
   StatusCallback cancel_callback_;
 
   // Used only by OpenFile, in order to clone the file handle back to the
   // requesting process.
   base::ProcessHandle peer_handle_;
 
   // A flag to make sure we call operation only once per instance.
   OperationType pending_operation_;
 
   // LocalFileSystemOperation instance is usually deleted upon completion but
   // could be deleted while it has inflight callbacks when Cancel is called.
   base::WeakPtrFactory<LocalFileSystemOperation> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalFileSystemOperation);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_LOCAL_FILE_SYSTEM_OPERATION_H_