xpcom/io/NonBlockingAsyncInputStream.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef NonBlockingAsyncInputStream_h
   7 #define NonBlockingAsyncInputStream_h
   8
   9 #include "mozilla/Attributes.h"
  10 #include "mozilla/Maybe.h"
  11 #include "mozilla/Mutex.h"
  12 #include "nsCOMPtr.h"
  13 #include "nsIAsyncInputStream.h"
  14 #include "nsICloneableInputStream.h"
  15 #include "nsIIPCSerializableInputStream.h"
  16 #include "nsISeekableStream.h"
  17
  18 // This class aims to wrap a non-blocking and non-async inputStream and expose
  19 // it as nsIAsyncInputStream.
  20 // Probably you don't want to use this class directly. Instead use
  21 // NS_MakeAsyncNonBlockingInputStream() as it will handle different stream
  22 // variants without requiring you to special-case them yourself.
  23
  24 namespace mozilla {
  25
  26 class NonBlockingAsyncInputStream final : public nsIAsyncInputStream,
  27                                           public nsICloneableInputStream,
  28                                           public nsIIPCSerializableInputStream,
  29                                           public nsISeekableStream {
  30  public:
  31   NS_DECL_THREADSAFE_ISUPPORTS
  32   NS_DECL_NSIINPUTSTREAM
  33   NS_DECL_NSIASYNCINPUTSTREAM
  34   NS_DECL_NSICLONEABLEINPUTSTREAM
  35   NS_DECL_NSIIPCSERIALIZABLEINPUTSTREAM
  36   NS_DECL_NSISEEKABLESTREAM
  37   NS_DECL_NSITELLABLESTREAM
  38
  39   // |aInputStream| must be a non-blocking, non-async inputSteam.
  40   static nsresult Create(already_AddRefed<nsIInputStream> aInputStream,
  41                          nsIAsyncInputStream** aAsyncInputStream);
  42
  43  private:
  44   explicit NonBlockingAsyncInputStream(
  45       already_AddRefed<nsIInputStream> aInputStream);
  46   ~NonBlockingAsyncInputStream();
  47
  48   template <typename M>
  49   void SerializeInternal(mozilla::ipc::InputStreamParams& aParams,
  50                          FileDescriptorArray& aFileDescriptors,
  51                          bool aDelayedStart, uint32_t aMaxSize,
  52                          uint32_t* aSizeUsed, M* aManager);
  53
  54   class AsyncWaitRunnable;
  55
  56   void RunAsyncWaitCallback(AsyncWaitRunnable* aRunnable,
  57                             already_AddRefed<nsIInputStreamCallback> aCallback);
  58
  59   nsCOMPtr<nsIInputStream> mInputStream;
  60
  61   // Raw pointers because these are just QI of mInputStream.
  62   nsICloneableInputStream* MOZ_NON_OWNING_REF mWeakCloneableInputStream;
  63   nsIIPCSerializableInputStream* MOZ_NON_OWNING_REF
  64       mWeakIPCSerializableInputStream;
  65   nsISeekableStream* MOZ_NON_OWNING_REF mWeakSeekableInputStream;
  66   nsITellableStream* MOZ_NON_OWNING_REF mWeakTellableInputStream;
  67
  68   Mutex mLock;
  69
  70   struct WaitClosureOnly {
  71     WaitClosureOnly(AsyncWaitRunnable* aRunnable, nsIEventTarget* aEventTarget);
  72
  73     RefPtr<AsyncWaitRunnable> mRunnable;
  74     nsCOMPtr<nsIEventTarget> mEventTarget;
  75   };
  76
  77   // This is set when AsyncWait is called with a callback and with
  78   // WAIT_CLOSURE_ONLY as flag.
  79   // This is protected by mLock.
  80   Maybe<WaitClosureOnly> mWaitClosureOnly;
  81
  82   // This is protected by mLock.
  83   RefPtr<AsyncWaitRunnable> mAsyncWaitCallback;
  84
  85   // This is protected by mLock.
  86   bool mClosed;
  87 };
  88
  89 }  // namespace mozilla
  90
  91 #endif  // NonBlockingAsyncInputStream_h