[BlobAsync] Patch 2: Common Constants

storage/common/blob_storage/blob_item_bytes_response.h

+// 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_BLOB_STORAGE_BLOB_ITEM_BYTES_RESPONSE_H_
+#define STORAGE_COMMON_BLOB_STORAGE_BLOB_ITEM_BYTES_RESPONSE_H_
+
+#include <stdint.h>
+#include <algorithm>
+#include <ostream>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "storage/common/storage_common_export.h"
+
+namespace storage {
+
+// This class is serialized over IPC to send blob item data, or to signal that
+// the memory has been populated.
+struct STORAGE_COMMON_EXPORT BlobItemBytesResponse {
+  // not using std::numeric_limits<T>::max() because of non-C++11 builds.
+  static const size_t kInvalidIndex = SIZE_MAX;
+
+  BlobItemBytesResponse();
+  explicit BlobItemBytesResponse(size_t request_number);
+  ~BlobItemBytesResponse();
+
+  char* allocate_mutable_data(size_t size) {
+    inline_data.resize(size);
+    return &inline_data[0];
+  }
+
+  size_t request_number;
+  std::vector<char> inline_data;
+};
+
+STORAGE_COMMON_EXPORT void PrintTo(const BlobItemBytesResponse& response,
+                                   std::ostream* os);
+
+#if defined(UNIT_TEST)
+STORAGE_COMMON_EXPORT inline bool operator==(const BlobItemBytesResponse& a,
+                                             const BlobItemBytesResponse& b) {
+  return a.request_number == b.request_number &&
+         a.inline_data.size() == b.inline_data.size() &&
+         std::equal(a.inline_data.begin(),
+                    a.inline_data.begin() + a.inline_data.size(),
+                    b.inline_data.begin());
+}
+
+STORAGE_COMMON_EXPORT inline bool operator!=(const BlobItemBytesResponse& a,
+                                             const BlobItemBytesResponse& b) {
+  return !(a == b);
+}
+#endif  // defined(UNIT_TEST)
+
+}  // namespace storage
+
+#endif  // STORAGE_COMMON_BLOB_STORAGE_BLOB_ITEM_BYTES_RESPONSE_H_