ipc/glue/InputStreamUtils.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_ipc_InputStreamUtils_h
   8 #define mozilla_ipc_InputStreamUtils_h
   9
  10 #include "mozilla/ipc/InputStreamParams.h"
  11 #include "nsCOMPtr.h"
  12 #include "nsIInputStream.h"
  13 #include "nsTArray.h"
  14
  15 namespace mozilla {
  16 namespace ipc {
  17
  18 class FileDescriptor;
  19
  20 // If you want to serialize an inputStream, please use SerializeIPCStream or
  21 // nsIInputStream directly.
  22 class InputStreamHelper {
  23  public:
  24   static void SerializedComplexity(nsIInputStream* aInputStream,
  25                                    uint32_t aMaxSize, uint32_t* aSizeUsed,
  26                                    uint32_t* aPipes, uint32_t* aTransferables);
  27
  28   // These 2 methods allow to serialize an inputStream into InputStreamParams.
  29   // The manager is needed in case a stream needs to serialize itself as
  30   // IPCRemoteStream.
  31   // The stream serializes itself fully only if the resulting IPC message will
  32   // be smaller than |aMaxSize|. Otherwise, the stream serializes itself as a
  33   // DataPipe, and, its content will be sent to the other side of the IPC pipe
  34   // in chunks. The IPC message size is returned into |aSizeUsed|.
  35   static void SerializeInputStream(nsIInputStream* aInputStream,
  36                                    InputStreamParams& aParams,
  37                                    uint32_t aMaxSize, uint32_t* aSizeUsed);
  38
  39   // When a stream wants to serialize itself as a DataPipe, it uses this method.
  40   static void SerializeInputStreamAsPipe(nsIInputStream* aInputStream,
  41                                          InputStreamParams& aParams);
  42
  43   static already_AddRefed<nsIInputStream> DeserializeInputStream(
  44       const InputStreamParams& aParams);
  45 };
  46
  47 }  // namespace ipc
  48 }  // namespace mozilla
  49
  50 #endif  // mozilla_ipc_InputStreamUtils_h