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 class PFileDescriptorSetChild;
  20 class PFileDescriptorSetParent;
  21 class PChildToParentStreamChild;
  22 class PParentToChildStreamParent;
  23
  24 // Provide two interfaces for sending PParentToChildStream and
  25 // PFileDescriptorSet constructor messages.
  26 class ParentToChildStreamActorManager {
  27  public:
  28   virtual PParentToChildStreamParent* SendPParentToChildStreamConstructor(
  29       PParentToChildStreamParent* aActor) = 0;
  30   virtual PFileDescriptorSetParent* SendPFileDescriptorSetConstructor(
  31       const FileDescriptor& aFD) = 0;
  32 };
  33
  34 class ChildToParentStreamActorManager {
  35  public:
  36   virtual PChildToParentStreamChild* SendPChildToParentStreamConstructor(
  37       PChildToParentStreamChild* aActor) = 0;
  38   virtual PFileDescriptorSetChild* SendPFileDescriptorSetConstructor(
  39       const FileDescriptor& aFD) = 0;
  40 };
  41
  42 // If you want to serialize an inputStream, please use AutoIPCStream.
  43 class InputStreamHelper {
  44  public:
  45   // These 2 methods allow to serialize an inputStream into InputStreamParams.
  46   // The manager is needed in case a stream needs to serialize itself as
  47   // IPCRemoteStream.
  48   // The stream serializes itself fully only if the resulting IPC message will
  49   // be smaller than |aMaxSize|. Otherwise, the stream serializes itself as
  50   // IPCRemoteStream, and, its content will be sent to the other side of the IPC
  51   // pipe in chunks. This sending can start immediatelly or at the first read
  52   // based on the value of |aDelayedStart|. The IPC message size is returned
  53   // into |aSizeUsed|.
  54   static void SerializeInputStream(nsIInputStream* aInputStream,
  55                                    InputStreamParams& aParams,
  56                                    nsTArray<FileDescriptor>& aFileDescriptors,
  57                                    bool aDelayedStart, uint32_t aMaxSize,
  58                                    uint32_t* aSizeUsed,
  59                                    ParentToChildStreamActorManager* aManager);
  60
  61   static void SerializeInputStream(nsIInputStream* aInputStream,
  62                                    InputStreamParams& aParams,
  63                                    nsTArray<FileDescriptor>& aFileDescriptors,
  64                                    bool aDelayedStart, uint32_t aMaxSize,
  65                                    uint32_t* aSizeUsed,
  66                                    ChildToParentStreamActorManager* aManager);
  67
  68   // When a stream wants to serialize itself as IPCRemoteStream, it uses one of
  69   // these methods.
  70   static void SerializeInputStreamAsPipe(
  71       nsIInputStream* aInputStream, InputStreamParams& aParams,
  72       bool aDelayedStart, ParentToChildStreamActorManager* aManager);
  73
  74   static void SerializeInputStreamAsPipe(
  75       nsIInputStream* aInputStream, InputStreamParams& aParams,
  76       bool aDelayedStart, ChildToParentStreamActorManager* aManager);
  77
  78   // After the sending of the inputStream into the IPC pipe, some of the
  79   // InputStreamParams data struct needs to be activated (IPCRemoteStream).
  80   // These 2 methods do that.
  81   static void PostSerializationActivation(InputStreamParams& aParams,
  82                                           bool aConsumedByIPC,
  83                                           bool aDelayedStart);
  84
  85   static void PostSerializationActivation(Maybe<InputStreamParams>& aParams,
  86                                           bool aConsumedByIPC,
  87                                           bool aDelayedStart);
  88
  89   static already_AddRefed<nsIInputStream> DeserializeInputStream(
  90       const InputStreamParams& aParams,
  91       const nsTArray<FileDescriptor>& aFileDescriptors);
  92 };
  93
  94 }  // namespace ipc
  95 }  // namespace mozilla
  96
  97 #endif  // mozilla_ipc_InputStreamUtils_h