FileAPI: Split recursive remove into multiple async tasks

webkit/fileapi/local_file_system_operation.h

Index: webkit/fileapi/local_file_system_operation.h
diff --git a/webkit/fileapi/local_file_system_operation.h b/webkit/fileapi/local_file_system_operation.h
index e80e91f4e68bddedd1845b6ef93b84ddde2a1e41..7a5b57c8fc99ea38f7112b462f7e08ba3354a13e 100644
--- a/webkit/fileapi/local_file_system_operation.h
+++ b/webkit/fileapi/local_file_system_operation.h
@@ -25,6 +25,7 @@ class CrosMountPointProvider;
 namespace fileapi {
 
 class FileSystemContext;
+class RemoveOperationDelegate;
 
 // FileSystemOperation implementation for local file systems.
 class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
@@ -78,10 +79,39 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
       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);
 
@@ -108,6 +138,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   friend class FileSystemQuotaTest;
   friend class LocalFileSystemTestOriginHelper;
 
+  friend class RemoveOperationDelegate;
   friend class SyncableFileSystemOperation;
 
   LocalFileSystemOperation(
@@ -119,6 +150,8 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   }
 
   FileSystemOperationContext* operation_context() const {
+    if (overriding_operation_context_)
+      return overriding_operation_context_;
     return operation_context_.get();
   }
 
@@ -230,12 +263,24 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   // 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_;
@@ -248,6 +293,8 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   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;