[BlobAsync] Moving async handling into BlobStorageContext & quota out.

storage/browser/blob/blob_async_transport_request_builder.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_BROWSER_BLOB_BLOB_ASYNC_TRANSPORT_REQUEST_BUILDER_H_
-#define STORAGE_BROWSER_BLOB_BLOB_ASYNC_TRANSPORT_REQUEST_BUILDER_H_
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include <map>
-#include <memory>
-#include <vector>
-
-#include "base/macros.h"
-#include "storage/browser/blob/blob_data_builder.h"
-#include "storage/browser/storage_browser_export.h"
-#include "storage/common/blob_storage/blob_item_bytes_request.h"
-#include "storage/common/data_element.h"
-
-namespace storage {
-
-// This class generates the requests needed to asynchronously transport the
-// given blob items from the renderer to the browser. The main job of this class
-// is to segment the memory being transfered to efficiently use shared memory,
-// file, and IPC max sizes.
-// Note: This class does not compute requests by using the 'shortcut' method,
-//       where the data is already present in the blob description, and will
-//       always give the caller requests for requesting all data from the
-//       renderer.
-class STORAGE_EXPORT BlobAsyncTransportRequestBuilder {
- public:
-  struct RendererMemoryItemRequest {
-    RendererMemoryItemRequest();
-    // This is the index of the item in the builder on the browser side.
-    size_t browser_item_index;
-    // Note: For files this offset should always be 0, as the file offset in
-    //       segmentation is handled by the handle_offset in the message.  This
-    //       offset is used for populating a chunk when the data comes back to
-    //       the browser.
-    size_t browser_item_offset;
-    BlobItemBytesRequest message;
-  };
-
-  BlobAsyncTransportRequestBuilder();
-  virtual ~BlobAsyncTransportRequestBuilder();
-
-  // Initializes the request builder for file requests. One or more files are
-  // created to hold the given data. Each file can hold data from multiple
-  // items, and the data from each item can be in multiple files.
-  // See file_handle_sizes() for the generated file sizes.
-  // max_file_size: This is the maximum size for a file to back a blob.
-  // blob_total_size: This is the total in-memory size of the blob.
-  // elements: These are the descriptions of the blob items being sent from the
-  //           renderer.
-  // builder: This is the builder that is populated with the 'future' versions
-  //          of the data elements. In this case, we call 'AppendFutureData' in
-  //          the items that we expect to be backed by files writen by the
-  //          renderer.
-  void InitializeForFileRequests(size_t max_file_size,
-                                 uint64_t blob_total_size,
-                                 const std::vector<DataElement>& elements,
-                                 BlobDataBuilder* builder);
-
-  // Initializes the request builder for shared memory requests. We try to
-  // consolidate as much memory as possible in each shared memory segment we
-  // use.
-  // See shared_memory_handle_sizes() for the shared memory sizes.
-  // max_shared_memory_size: This is the maximum size for a shared memory
-  //                         segment used to transport the data between renderer
-  //                         and browser.
-  // blob_total_size: This is the total in-memory size of the blob.
-  // elements: These are the descriptions of the blob items being sent from the
-  //           renderer.
-  // builder: This is the builder that is populated with the 'future' versions
-  //          of the data elements. In this case, we call 'AppendFutureData' for
-  //          the items we expect to be populated later.
-  void InitializeForSharedMemoryRequests(
-      size_t max_shared_memory_size,
-      uint64_t blob_total_size,
-      const std::vector<DataElement>& elements,
-      BlobDataBuilder* builder);
-
-  // Initializes the request builder for IPC requests. We put as much memory
-  // in a single IPC request as possible.
-  // max_ipc_memory_size: This is the maximum size for an IPC message which will
-  //                      be used to transport memory from the renderer to the
-  //                      browser.
-  // blob_total_size: This is the total in-memory size of the blob.
-  // elements: These are the descriptions of the blob items being sent from the
-  //           renderer.
-  // builder: This is the builder that is populated with the 'future' versions
-  //          of the data elements. In this case, we call 'AppendFutureData' for
-  //          the items we expect to be populated later.
-  void InitializeForIPCRequests(size_t max_ipc_memory_size,
-                                uint64_t blob_total_size,
-                                const std::vector<DataElement>& elements,
-                                BlobDataBuilder* builder);
-
-  // The sizes of the shared memory handles being used (by handle index).
-  const std::vector<size_t>& shared_memory_sizes() const {
-    return shared_memory_sizes_;
-  }
-
-  // The sizes of the file handles being used (by handle index).
-  const std::vector<size_t>& file_sizes() const { return file_sizes_; }
-
-  // The requests for memory, segmented as described above, along with their
-  // destination browser indexes and offsets.
-  const std::vector<RendererMemoryItemRequest>& requests() const {
-    return requests_;
-  }
-
-  // The total bytes size of memory items in the blob.
-  uint64_t total_bytes_size() const { return total_bytes_size_; }
-
-  static bool ShouldBeShortcut(const std::vector<DataElement>& items,
-                               size_t memory_available);
-
- private:
-  static void ComputeHandleSizes(uint64_t total_memory_size,
-                                 size_t max_segment_size,
-                                 std::vector<size_t>* segment_sizes);
-
-  std::vector<size_t> shared_memory_sizes_;
-  // The size of the files is capped by the |max_file_size| argument in
-  // InitializeForFileRequests, so we can just use size_t.
-  std::vector<size_t> file_sizes_;
-
-  uint64_t total_bytes_size_;
-  std::vector<RendererMemoryItemRequest> requests_;
-
-  DISALLOW_COPY_AND_ASSIGN(BlobAsyncTransportRequestBuilder);
-};
-
-}  // namespace storage
-
-#endif  // STORAGE_BROWSER_BLOB_BLOB_ASYNC_TRANSPORT_REQUEST_BUILDER_H_