Adds ImageWriterPrivate.destroyPartitions operation.

chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc

+// Copyright 2013 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.
+
+#include "base/file_util.h"
+#include "chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.h"
+#include "chrome/browser/extensions/api/image_writer_private/error_messages.h"
+
+namespace extensions {
+namespace image_writer {
+
+// Number of bytes for the maximum partition table size.  By wiping this many
+// bytes we can essentially guarantee the header and associated information will
+// be wiped. See http://crbug.com/328246 for more information.
+const int kPartitionTableSize = 1 * 1024;
+
+DestroyPartitionsOperation::DestroyPartitionsOperation(
+    base::WeakPtr<OperationManager> manager,
+    const ExtensionId& extension_id,
+    const std::string& storage_unit_id)
+    : Operation(manager, extension_id, storage_unit_id) {
+  verify_write_ = false;
+}
+
+DestroyPartitionsOperation::~DestroyPartitionsOperation() {}
+
+void DestroyPartitionsOperation::Start() {
+  if (!temp_dir_.CreateUniqueTempDir()) {
+    Error(error::kTempDirError);
+    return;
+  }
+
+  if (!base::CreateTemporaryFileInDir(temp_dir_.path(), &image_path_)) {
+    Error(error::kTempFileError);
+    return;
+  }
+
+  scoped_ptr<char[]> buffer(new char[kPartitionTableSize]);
+  memset(buffer.get(), 0, kPartitionTableSize);
+
+  if (file_util::WriteFile(image_path_, buffer.get(), kPartitionTableSize) !=
+      kPartitionTableSize) {
+    Error(error::kTempFileError);
+    return;
+  }
+
+  WriteStart();
+}
+
+}  // namespace image_writer
+}  // namespace extensions