[BlobAsync] Patch 4: Browser Classes & Logic.

storage/common/fileapi/blob_item_bytes_request.h

Index: storage/common/fileapi/blob_item_bytes_request.h
diff --git a/storage/common/fileapi/blob_item_bytes_request.h b/storage/common/fileapi/blob_item_bytes_request.h
new file mode 100644
index 0000000000000000000000000000000000000000..317434b3730c67f66008e3d142e55d4787b35906
--- /dev/null
+++ b/storage/common/fileapi/blob_item_bytes_request.h
@@ -0,0 +1,125 @@
+// Copyright 2015 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 STORAGE_COMMON_FILEAPI_BLOB_ITEM_BYTES_REQUEST_H_
+#define STORAGE_COMMON_FILEAPI_BLOB_ITEM_BYTES_REQUEST_H_
+
+#include <stdint.h>
+
+#include "base/basictypes.h"
+
+namespace storage {
+
+enum IPCBlobItemRequestStrategy {
+  IPC_BLOB_ITEM_REQUEST_STRATEGY_UNKNOWN = 0,
+  IPC_BLOB_ITEM_REQUEST_STRATEGY_IPC,
+  IPC_BLOB_ITEM_REQUEST_STRATEGY_SHARED_MEMORY,
+  IPC_BLOB_ITEM_REQUEST_STRATEGY_FILE
+};
+
+enum IPCBlobCreationCancelCode {

[kinuko, 2015/05/25 08:32:03]

Not yet used?

[dmurph, 2015/06/13 00:13:10]

No not yet, this is for the IPC messages that will come in the next patch.

+  IPC_BLOB_CREATION_CANCEL_UNKNOWN = 0,
+  IPC_BLOB_CREATION_CANCEL_OUT_OF_MEMORY,
+  IPC_BLOB_CREATION_CANCEL_FILE_WRITE_FAILED
+};
+
+// This class is serialized over IPC to request bytes from a blob item.
+struct BlobItemBytesRequest {
+  // not using std::numeric_limits<T>::max() because of non-C++11 builds.
+  static const size_t kInvalidIndex = SIZE_MAX;
+  static const uint64_t kInvalidSize = kuint64max;
+
+  static BlobItemBytesRequest CreateIPCRequest(size_t request_number,
+                                               size_t renderer_item_index,
+                                               uint64_t renderer_item_offset,
+                                               uint64_t size) {
+    return BlobItemBytesRequest(
+        request_number, IPC_BLOB_ITEM_REQUEST_STRATEGY_IPC, renderer_item_index,
+        renderer_item_offset, size, kInvalidIndex, kInvalidSize);
+  }
+
+  static BlobItemBytesRequest CreateSharedMemoryRequest(
+      size_t request_number, size_t renderer_item_index,
+      uint64_t renderer_item_offset, uint64_t size, size_t handle_index,
+      uint64_t handle_offset) {
+    return BlobItemBytesRequest(request_number,
+                                IPC_BLOB_ITEM_REQUEST_STRATEGY_SHARED_MEMORY,
+                                renderer_item_index, renderer_item_offset, size,
+                                handle_index, handle_offset);
+  }
+
+  static BlobItemBytesRequest CreateFileRequest(size_t request_number,
+                                                size_t renderer_item_index,
+                                                uint64_t renderer_item_offset,
+                                                uint64_t size,
+                                                size_t handle_index,
+                                                uint64_t handle_offset) {
+    return BlobItemBytesRequest(request_number,
+                                IPC_BLOB_ITEM_REQUEST_STRATEGY_FILE,
+                                renderer_item_index, renderer_item_offset, size,
+                                handle_index, handle_offset);
+  }
+
+  BlobItemBytesRequest()
+      : request_number(kInvalidIndex),
+        transport_strategy(IPC_BLOB_ITEM_REQUEST_STRATEGY_UNKNOWN),
+        renderer_item_index(kInvalidIndex),
+        renderer_item_offset(kInvalidSize),
+        size(kInvalidSize),
+        handle_index(kInvalidIndex),
+        handle_offset(kInvalidSize) {}
+  ~BlobItemBytesRequest() {}
+
+  BlobItemBytesRequest(size_t request_number,
+                       IPCBlobItemRequestStrategy transport_strategy,
+                       size_t renderer_item_index,
+                       uint64_t renderer_item_offset, uint64_t size,
+                       size_t handle_index, uint64_t handle_offset)
+      : request_number(request_number),
+        transport_strategy(transport_strategy),
+        renderer_item_index(renderer_item_index),
+        renderer_item_offset(renderer_item_offset),
+        size(size),
+        handle_index(handle_index),
+        handle_offset(handle_offset) {}
+
+  size_t request_number;
+  IPCBlobItemRequestStrategy transport_strategy;
+  size_t renderer_item_index;
+  uint64_t renderer_item_offset;
+  uint64_t size;
+  size_t handle_index;
+  uint64_t handle_offset;
+};
+
+#if defined(UNIT_TEST)
+inline bool operator==(const BlobItemBytesRequest& a,
+                       const BlobItemBytesRequest& b) {
+  return a.request_number == b.request_number &&
+         a.transport_strategy == b.transport_strategy &&
+         a.renderer_item_index == b.renderer_item_index &&
+         a.renderer_item_offset == b.renderer_item_offset && a.size == b.size &&
+         a.handle_index == b.handle_index && a.handle_offset == b.handle_offset;
+}
+
+inline bool operator!=(const BlobItemBytesRequest& a,
+                       const BlobItemBytesRequest& b) {
+  return !(a == b);
+}
+
+inline ::std::ostream& operator<<(::std::ostream& os,
+                                  const BlobItemBytesRequest& request) {
+  return os << "{ request_number: " << request.request_number
+            << ", transport_strategy: " << request.transport_strategy
+            << ", renderer_item_index: " << request.renderer_item_index
+            << ", renderer_item_offset: " << request.renderer_item_offset
+            << ", size: " << request.size
+            << ", handle_index: " << request.handle_index
+            << ", handle_offset: " << request.handle_offset << " }";
+}
+#endif  // defined(UNIT_TEST)
+
+}  // namespace storage
+
+#endif  // STORAGE_COMMON_FILEAPI_BLOB_ITEM_BYTES_REQUEST_H_