Add m-esr52 at 52.6.0

1 files changed, 835 insertions, 0 deletions

diff --git a/xpcom/io/nsMultiplexInputStream.cpp b/xpcom/io/nsMultiplexInputStream.cpp
new file mode 100644
index 0000000000..4aa397c37d
--- /dev/null
+++ b/xpcom/io/nsMultiplexInputStream.cpp
@@ -0,0 +1,835 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * The multiplex stream concatenates a list of input streams into a single
+ * stream.
+ */
+
+#include "mozilla/Attributes.h"
+#include "mozilla/MathAlgorithms.h"
+#include "mozilla/Mutex.h"
+
+#include "base/basictypes.h"
+
+#include "nsMultiplexInputStream.h"
+#include "nsICloneableInputStream.h"
+#include "nsIMultiplexInputStream.h"
+#include "nsISeekableStream.h"
+#include "nsCOMPtr.h"
+#include "nsCOMArray.h"
+#include "nsIClassInfoImpl.h"
+#include "nsIIPCSerializableInputStream.h"
+#include "mozilla/ipc/InputStreamUtils.h"
+
+using namespace mozilla;
+using namespace mozilla::ipc;
+
+using mozilla::DeprecatedAbs;
+using mozilla::Maybe;
+using mozilla::Nothing;
+using mozilla::Some;
+
+class nsMultiplexInputStream final
+  : public nsIMultiplexInputStream
+  , public nsISeekableStream
+  , public nsIIPCSerializableInputStream
+  , public nsICloneableInputStream
+{
+public:
+  nsMultiplexInputStream();
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIINPUTSTREAM
+  NS_DECL_NSIMULTIPLEXINPUTSTREAM
+  NS_DECL_NSISEEKABLESTREAM
+  NS_DECL_NSIIPCSERIALIZABLEINPUTSTREAM
+  NS_DECL_NSICLONEABLEINPUTSTREAM
+
+private:
+  ~nsMultiplexInputStream()
+  {
+  }
+
+  struct MOZ_STACK_CLASS ReadSegmentsState
+  {
+    nsCOMPtr<nsIInputStream> mThisStream;
+    uint32_t mOffset;
+    nsWriteSegmentFun mWriter;
+    void* mClosure;
+    bool mDone;
+  };
+
+  static nsresult ReadSegCb(nsIInputStream* aIn, void* aClosure,
+                            const char* aFromRawSegment, uint32_t aToOffset,
+                            uint32_t aCount, uint32_t* aWriteCount);
+
+  Mutex mLock; // Protects access to all data members.
+  nsTArray<nsCOMPtr<nsIInputStream>> mStreams;
+  uint32_t mCurrentStream;
+  bool mStartedReadingCurrent;
+  nsresult mStatus;
+};
+
+NS_IMPL_ADDREF(nsMultiplexInputStream)
+NS_IMPL_RELEASE(nsMultiplexInputStream)
+
+NS_IMPL_CLASSINFO(nsMultiplexInputStream, nullptr, nsIClassInfo::THREADSAFE,
+                  NS_MULTIPLEXINPUTSTREAM_CID)
+
+NS_IMPL_QUERY_INTERFACE_CI(nsMultiplexInputStream,
+                           nsIMultiplexInputStream,
+                           nsIInputStream,
+                           nsISeekableStream,
+                           nsIIPCSerializableInputStream,
+                           nsICloneableInputStream)
+NS_IMPL_CI_INTERFACE_GETTER(nsMultiplexInputStream,
+                            nsIMultiplexInputStream,
+                            nsIInputStream,
+                            nsISeekableStream)
+
+static nsresult
+AvailableMaybeSeek(nsIInputStream* aStream, uint64_t* aResult)
+{
+  nsresult rv = aStream->Available(aResult);
+  if (rv == NS_BASE_STREAM_CLOSED) {
+    // Blindly seek to the current position if Available() returns
+    // NS_BASE_STREAM_CLOSED.
+    // If nsIFileInputStream is closed in Read() due to CLOSE_ON_EOF flag,
+    // Seek() could reopen the file if REOPEN_ON_REWIND flag is set.
+    nsCOMPtr<nsISeekableStream> seekable = do_QueryInterface(aStream);
+    if (seekable) {
+      nsresult rvSeek = seekable->Seek(nsISeekableStream::NS_SEEK_CUR, 0);
+      if (NS_SUCCEEDED(rvSeek)) {
+        rv = aStream->Available(aResult);
+      }
+    }
+  }
+  return rv;
+}
+
+static nsresult
+TellMaybeSeek(nsISeekableStream* aSeekable, int64_t* aResult)
+{
+  nsresult rv = aSeekable->Tell(aResult);
+  if (rv == NS_BASE_STREAM_CLOSED) {
+    // Blindly seek to the current position if Tell() returns
+    // NS_BASE_STREAM_CLOSED.
+    // If nsIFileInputStream is closed in Read() due to CLOSE_ON_EOF flag,
+    // Seek() could reopen the file if REOPEN_ON_REWIND flag is set.
+    nsresult rvSeek = aSeekable->Seek(nsISeekableStream::NS_SEEK_CUR, 0);
+    if (NS_SUCCEEDED(rvSeek)) {
+      rv = aSeekable->Tell(aResult);
+    }
+  }
+  return rv;
+}
+
+nsMultiplexInputStream::nsMultiplexInputStream()
+  : mLock("nsMultiplexInputStream lock"),
+    mCurrentStream(0),
+    mStartedReadingCurrent(false),
+    mStatus(NS_OK)
+{
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::GetCount(uint32_t* aCount)
+{
+  MutexAutoLock lock(mLock);
+  *aCount = mStreams.Length();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::AppendStream(nsIInputStream* aStream)
+{
+  MutexAutoLock lock(mLock);
+  return mStreams.AppendElement(aStream) ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::InsertStream(nsIInputStream* aStream, uint32_t aIndex)
+{
+  MutexAutoLock lock(mLock);
+  mStreams.InsertElementAt(aIndex, aStream);
+  if (mCurrentStream > aIndex ||
+      (mCurrentStream == aIndex && mStartedReadingCurrent)) {
+    ++mCurrentStream;
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::RemoveStream(uint32_t aIndex)
+{
+  MutexAutoLock lock(mLock);
+  mStreams.RemoveElementAt(aIndex);
+  if (mCurrentStream > aIndex) {
+    --mCurrentStream;
+  } else if (mCurrentStream == aIndex) {
+    mStartedReadingCurrent = false;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::GetStream(uint32_t aIndex, nsIInputStream** aResult)
+{
+  MutexAutoLock lock(mLock);
+  *aResult = mStreams.SafeElementAt(aIndex, nullptr);
+  if (NS_WARN_IF(!*aResult)) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  NS_ADDREF(*aResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::Close()
+{
+  MutexAutoLock lock(mLock);
+  mStatus = NS_BASE_STREAM_CLOSED;
+
+  nsresult rv = NS_OK;
+
+  uint32_t len = mStreams.Length();
+  for (uint32_t i = 0; i < len; ++i) {
+    nsresult rv2 = mStreams[i]->Close();
+    // We still want to close all streams, but we should return an error
+    if (NS_FAILED(rv2)) {
+      rv = rv2;
+    }
+  }
+  return rv;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::Available(uint64_t* aResult)
+{
+  MutexAutoLock lock(mLock);
+  if (NS_FAILED(mStatus)) {
+    return mStatus;
+  }
+
+  uint64_t avail = 0;
+
+  uint32_t len = mStreams.Length();
+  for (uint32_t i = mCurrentStream; i < len; i++) {
+    uint64_t streamAvail;
+    mStatus = AvailableMaybeSeek(mStreams[i], &streamAvail);
+    if (NS_WARN_IF(NS_FAILED(mStatus))) {
+      return mStatus;
+    }
+    avail += streamAvail;
+  }
+  *aResult = avail;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::Read(char* aBuf, uint32_t aCount, uint32_t* aResult)
+{
+  MutexAutoLock lock(mLock);
+  // It is tempting to implement this method in terms of ReadSegments, but
+  // that would prevent this class from being used with streams that only
+  // implement Read (e.g., file streams).
+
+  *aResult = 0;
+
+  if (mStatus == NS_BASE_STREAM_CLOSED) {
+    return NS_OK;
+  }
+  if (NS_FAILED(mStatus)) {
+    return mStatus;
+  }
+
+  nsresult rv = NS_OK;
+
+  uint32_t len = mStreams.Length();
+  while (mCurrentStream < len && aCount) {
+    uint32_t read;
+    rv = mStreams[mCurrentStream]->Read(aBuf, aCount, &read);
+
+    // XXX some streams return NS_BASE_STREAM_CLOSED to indicate EOF.
+    // (This is a bug in those stream implementations)
+    if (rv == NS_BASE_STREAM_CLOSED) {
+      NS_NOTREACHED("Input stream's Read method returned NS_BASE_STREAM_CLOSED");
+      rv = NS_OK;
+      read = 0;
+    } else if (NS_FAILED(rv)) {
+      break;
+    }
+
+    if (read == 0) {
+      ++mCurrentStream;
+      mStartedReadingCurrent = false;
+    } else {
+      NS_ASSERTION(aCount >= read, "Read more than requested");
+      *aResult += read;
+      aCount -= read;
+      aBuf += read;
+      mStartedReadingCurrent = true;
+    }
+  }
+  return *aResult ? NS_OK : rv;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::ReadSegments(nsWriteSegmentFun aWriter, void* aClosure,
+                                     uint32_t aCount, uint32_t* aResult)
+{
+  MutexAutoLock lock(mLock);
+
+  if (mStatus == NS_BASE_STREAM_CLOSED) {
+    *aResult = 0;
+    return NS_OK;
+  }
+  if (NS_FAILED(mStatus)) {
+    return mStatus;
+  }
+
+  NS_ASSERTION(aWriter, "missing aWriter");
+
+  nsresult rv = NS_OK;
+  ReadSegmentsState state;
+  state.mThisStream = this;
+  state.mOffset = 0;
+  state.mWriter = aWriter;
+  state.mClosure = aClosure;
+  state.mDone = false;
+
+  uint32_t len = mStreams.Length();
+  while (mCurrentStream < len && aCount) {
+    uint32_t read;
+    rv = mStreams[mCurrentStream]->ReadSegments(ReadSegCb, &state, aCount, &read);
+
+    // XXX some streams return NS_BASE_STREAM_CLOSED to indicate EOF.
+    // (This is a bug in those stream implementations)
+    if (rv == NS_BASE_STREAM_CLOSED) {
+      NS_NOTREACHED("Input stream's Read method returned NS_BASE_STREAM_CLOSED");
+      rv = NS_OK;
+      read = 0;
+    }
+
+    // if |aWriter| decided to stop reading segments...
+    if (state.mDone || NS_FAILED(rv)) {
+      break;
+    }
+
+    // if stream is empty, then advance to the next stream.
+    if (read == 0) {
+      ++mCurrentStream;
+      mStartedReadingCurrent = false;
+    } else {
+      NS_ASSERTION(aCount >= read, "Read more than requested");
+      state.mOffset += read;
+      aCount -= read;
+      mStartedReadingCurrent = true;
+    }
+  }
+
+  // if we successfully read some data, then this call succeeded.
+  *aResult = state.mOffset;
+  return state.mOffset ? NS_OK : rv;
+}
+
+nsresult
+nsMultiplexInputStream::ReadSegCb(nsIInputStream* aIn, void* aClosure,
+                                  const char* aFromRawSegment,
+                                  uint32_t aToOffset, uint32_t aCount,
+                                  uint32_t* aWriteCount)
+{
+  nsresult rv;
+  ReadSegmentsState* state = (ReadSegmentsState*)aClosure;
+  rv = (state->mWriter)(state->mThisStream,
+                        state->mClosure,
+                        aFromRawSegment,
+                        aToOffset + state->mOffset,
+                        aCount,
+                        aWriteCount);
+  if (NS_FAILED(rv)) {
+    state->mDone = true;
+  }
+  return rv;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::IsNonBlocking(bool* aNonBlocking)
+{
+  MutexAutoLock lock(mLock);
+
+  uint32_t len = mStreams.Length();
+  if (len == 0) {
+    // Claim to be non-blocking, since we won't block the caller.
+    // On the other hand we'll never return NS_BASE_STREAM_WOULD_BLOCK,
+    // so maybe we should claim to be blocking?  It probably doesn't
+    // matter in practice.
+    *aNonBlocking = true;
+    return NS_OK;
+  }
+  for (uint32_t i = 0; i < len; ++i) {
+    nsresult rv = mStreams[i]->IsNonBlocking(aNonBlocking);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+    // If one is non-blocking the entire stream becomes non-blocking
+    // (except that we don't implement nsIAsyncInputStream, so there's
+    //  not much for the caller to do if Read returns "would block")
+    if (*aNonBlocking) {
+      return NS_OK;
+    }
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::Seek(int32_t aWhence, int64_t aOffset)
+{
+  MutexAutoLock lock(mLock);
+
+  if (NS_FAILED(mStatus)) {
+    return mStatus;
+  }
+
+  nsresult rv;
+
+  uint32_t oldCurrentStream = mCurrentStream;
+  bool oldStartedReadingCurrent = mStartedReadingCurrent;
+
+  if (aWhence == NS_SEEK_SET) {
+    int64_t remaining = aOffset;
+    if (aOffset == 0) {
+      mCurrentStream = 0;
+    }
+    for (uint32_t i = 0; i < mStreams.Length(); ++i) {
+      nsCOMPtr<nsISeekableStream> stream =
+        do_QueryInterface(mStreams[i]);
+      if (!stream) {
+        return NS_ERROR_FAILURE;
+      }
+
+      // See if all remaining streams should be rewound
+      if (remaining == 0) {
+        if (i < oldCurrentStream ||
+            (i == oldCurrentStream && oldStartedReadingCurrent)) {
+          rv = stream->Seek(NS_SEEK_SET, 0);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return rv;
+          }
+          continue;
+        } else {
+          break;
+        }
+      }
+
+      // Get position in current stream
+      int64_t streamPos;
+      if (i > oldCurrentStream ||
+          (i == oldCurrentStream && !oldStartedReadingCurrent)) {
+        streamPos = 0;
+      } else {
+        rv = TellMaybeSeek(stream, &streamPos);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+      }
+
+      // See if we need to seek current stream forward or backward
+      if (remaining < streamPos) {
+        rv = stream->Seek(NS_SEEK_SET, remaining);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+
+        mCurrentStream = i;
+        mStartedReadingCurrent = remaining != 0;
+
+        remaining = 0;
+      } else if (remaining > streamPos) {
+        if (i < oldCurrentStream) {
+          // We're already at end so no need to seek this stream
+          remaining -= streamPos;
+          NS_ASSERTION(remaining >= 0, "Remaining invalid");
+        } else {
+          uint64_t avail;
+          rv = AvailableMaybeSeek(mStreams[i], &avail);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return rv;
+          }
+
+          int64_t newPos = XPCOM_MIN(remaining, streamPos + (int64_t)avail);
+
+          rv = stream->Seek(NS_SEEK_SET, newPos);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return rv;
+          }
+
+          mCurrentStream = i;
+          mStartedReadingCurrent = true;
+
+          remaining -= newPos;
+          NS_ASSERTION(remaining >= 0, "Remaining invalid");
+        }
+      } else {
+        NS_ASSERTION(remaining == streamPos, "Huh?");
+        remaining = 0;
+      }
+    }
+
+    return NS_OK;
+  }
+
+  if (aWhence == NS_SEEK_CUR && aOffset > 0) {
+    int64_t remaining = aOffset;
+    for (uint32_t i = mCurrentStream; remaining && i < mStreams.Length(); ++i) {
+      nsCOMPtr<nsISeekableStream> stream =
+        do_QueryInterface(mStreams[i]);
+
+      uint64_t avail;
+      rv = AvailableMaybeSeek(mStreams[i], &avail);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return rv;
+      }
+
+      int64_t seek = XPCOM_MIN((int64_t)avail, remaining);
+
+      rv = stream->Seek(NS_SEEK_CUR, seek);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return rv;
+      }
+
+      mCurrentStream = i;
+      mStartedReadingCurrent = true;
+
+      remaining -= seek;
+    }
+
+    return NS_OK;
+  }
+
+  if (aWhence == NS_SEEK_CUR && aOffset < 0) {
+    int64_t remaining = -aOffset;
+    for (uint32_t i = mCurrentStream; remaining && i != (uint32_t)-1; --i) {
+      nsCOMPtr<nsISeekableStream> stream =
+        do_QueryInterface(mStreams[i]);
+
+      int64_t pos;
+      rv = TellMaybeSeek(stream, &pos);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return rv;
+      }
+
+      int64_t seek = XPCOM_MIN(pos, remaining);
+
+      rv = stream->Seek(NS_SEEK_CUR, -seek);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return rv;
+      }
+
+      mCurrentStream = i;
+      mStartedReadingCurrent = seek != -pos;
+
+      remaining -= seek;
+    }
+
+    return NS_OK;
+  }
+
+  if (aWhence == NS_SEEK_CUR) {
+    NS_ASSERTION(aOffset == 0, "Should have handled all non-zero values");
+
+    return NS_OK;
+  }
+
+  if (aWhence == NS_SEEK_END) {
+    if (aOffset > 0) {
+      return NS_ERROR_INVALID_ARG;
+    }
+    int64_t remaining = aOffset;
+    for (uint32_t i = mStreams.Length() - 1; i != (uint32_t)-1; --i) {
+      nsCOMPtr<nsISeekableStream> stream =
+        do_QueryInterface(mStreams[i]);
+
+      // See if all remaining streams should be seeked to end
+      if (remaining == 0) {
+        if (i >= oldCurrentStream) {
+          rv = stream->Seek(NS_SEEK_END, 0);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return rv;
+          }
+        } else {
+          break;
+        }
+      }
+
+      // Get position in current stream
+      int64_t streamPos;
+      if (i < oldCurrentStream) {
+        streamPos = 0;
+      } else {
+        uint64_t avail;
+        rv = AvailableMaybeSeek(mStreams[i], &avail);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+
+        streamPos = avail;
+      }
+
+      // See if we have enough data in the current stream.
+      if (DeprecatedAbs(remaining) < streamPos) {
+        rv = stream->Seek(NS_SEEK_END, remaining);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+
+        mCurrentStream = i;
+        mStartedReadingCurrent = true;
+
+        remaining = 0;
+      } else if (DeprecatedAbs(remaining) > streamPos) {
+        if (i > oldCurrentStream ||
+            (i == oldCurrentStream && !oldStartedReadingCurrent)) {
+          // We're already at start so no need to seek this stream
+          remaining += streamPos;
+        } else {
+          int64_t avail;
+          rv = TellMaybeSeek(stream, &avail);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return rv;
+          }
+
+          int64_t newPos = streamPos + XPCOM_MIN(avail, DeprecatedAbs(remaining));
+
+          rv = stream->Seek(NS_SEEK_END, -newPos);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return rv;
+          }
+
+          mCurrentStream = i;
+          mStartedReadingCurrent = true;
+
+          remaining += newPos;
+        }
+      } else {
+        NS_ASSERTION(remaining == streamPos, "Huh?");
+        remaining = 0;
+      }
+    }
+
+    return NS_OK;
+  }
+
+  // other Seeks not implemented yet
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::Tell(int64_t* aResult)
+{
+  MutexAutoLock lock(mLock);
+
+  if (NS_FAILED(mStatus)) {
+    return mStatus;
+  }
+
+  nsresult rv;
+  int64_t ret64 = 0;
+  uint32_t i, last;
+  last = mStartedReadingCurrent ? mCurrentStream + 1 : mCurrentStream;
+  for (i = 0; i < last; ++i) {
+    nsCOMPtr<nsISeekableStream> stream = do_QueryInterface(mStreams[i]);
+    if (NS_WARN_IF(!stream)) {
+      return NS_ERROR_NO_INTERFACE;
+    }
+
+    int64_t pos;
+    rv = TellMaybeSeek(stream, &pos);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+    ret64 += pos;
+  }
+  *aResult =  ret64;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::SetEOF()
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+nsresult
+nsMultiplexInputStreamConstructor(nsISupports* aOuter,
+                                  REFNSIID aIID,
+                                  void** aResult)
+{
+  *aResult = nullptr;
+
+  if (aOuter) {
+    return NS_ERROR_NO_AGGREGATION;
+  }
+
+  RefPtr<nsMultiplexInputStream> inst = new nsMultiplexInputStream();
+
+  return inst->QueryInterface(aIID, aResult);
+}
+
+void
+nsMultiplexInputStream::Serialize(InputStreamParams& aParams,
+                                  FileDescriptorArray& aFileDescriptors)
+{
+  MutexAutoLock lock(mLock);
+
+  MultiplexInputStreamParams params;
+
+  uint32_t streamCount = mStreams.Length();
+
+  if (streamCount) {
+    InfallibleTArray<InputStreamParams>& streams = params.streams();
+
+    streams.SetCapacity(streamCount);
+    for (uint32_t index = 0; index < streamCount; index++) {
+      InputStreamParams childStreamParams;
+      SerializeInputStream(mStreams[index], childStreamParams,
+                           aFileDescriptors);
+
+      streams.AppendElement(childStreamParams);
+    }
+  }
+
+  params.currentStream() = mCurrentStream;
+  params.status() = mStatus;
+  params.startedReadingCurrent() = mStartedReadingCurrent;
+
+  aParams = params;
+}
+
+bool
+nsMultiplexInputStream::Deserialize(const InputStreamParams& aParams,
+                                    const FileDescriptorArray& aFileDescriptors)
+{
+  if (aParams.type() !=
+      InputStreamParams::TMultiplexInputStreamParams) {
+    NS_ERROR("Received unknown parameters from the other process!");
+    return false;
+  }
+
+  const MultiplexInputStreamParams& params =
+    aParams.get_MultiplexInputStreamParams();
+
+  const InfallibleTArray<InputStreamParams>& streams = params.streams();
+
+  uint32_t streamCount = streams.Length();
+  for (uint32_t index = 0; index < streamCount; index++) {
+    nsCOMPtr<nsIInputStream> stream =
+      DeserializeInputStream(streams[index], aFileDescriptors);
+    if (!stream) {
+      NS_WARNING("Deserialize failed!");
+      return false;
+    }
+
+    if (NS_FAILED(AppendStream(stream))) {
+      NS_WARNING("AppendStream failed!");
+      return false;
+    }
+  }
+
+  mCurrentStream = params.currentStream();
+  mStatus = params.status();
+  mStartedReadingCurrent = params.startedReadingCurrent();
+
+  return true;
+}
+
+Maybe<uint64_t>
+nsMultiplexInputStream::ExpectedSerializedLength()
+{
+  MutexAutoLock lock(mLock);
+
+  bool lengthValueExists = false;
+  uint64_t expectedLength = 0;
+  uint32_t streamCount = mStreams.Length();
+  for (uint32_t index = 0; index < streamCount; index++) {
+    nsCOMPtr<nsIIPCSerializableInputStream> stream = do_QueryInterface(mStreams[index]);
+    if (!stream) {
+      continue;
+    }
+    Maybe<uint64_t> length = stream->ExpectedSerializedLength();
+    if (length.isNothing()) {
+      continue;
+    }
+    lengthValueExists = true;
+    expectedLength += length.value();
+  }
+  return lengthValueExists ? Some(expectedLength) : Nothing();
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::GetCloneable(bool* aCloneable)
+{
+  MutexAutoLock lock(mLock);
+  //XXXnsm Cloning a multiplex stream which has started reading is not permitted
+  //right now.
+  if (mCurrentStream > 0 || mStartedReadingCurrent) {
+    *aCloneable = false;
+    return NS_OK;
+  }
+
+  uint32_t len = mStreams.Length();
+  for (uint32_t i = 0; i < len; ++i) {
+    nsCOMPtr<nsICloneableInputStream> cis = do_QueryInterface(mStreams[i]);
+    if (!cis || !cis->GetCloneable()) {
+      *aCloneable = false;
+      return NS_OK;
+    }
+  }
+
+  *aCloneable = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMultiplexInputStream::Clone(nsIInputStream** aClone)
+{
+  MutexAutoLock lock(mLock);
+
+  //XXXnsm Cloning a multiplex stream which has started reading is not permitted
+  //right now.
+  if (mCurrentStream > 0 || mStartedReadingCurrent) {
+    return NS_ERROR_FAILURE;
+  }
+
+  RefPtr<nsMultiplexInputStream> clone = new nsMultiplexInputStream();
+
+  nsresult rv;
+  uint32_t len = mStreams.Length();
+  for (uint32_t i = 0; i < len; ++i) {
+    nsCOMPtr<nsICloneableInputStream> substream = do_QueryInterface(mStreams[i]);
+    if (NS_WARN_IF(!substream)) {
+      return NS_ERROR_FAILURE;
+    }
+
+    nsCOMPtr<nsIInputStream> clonedSubstream;
+    rv = substream->Clone(getter_AddRefs(clonedSubstream));
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    rv = clone->AppendStream(clonedSubstream);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+  }
+
+  clone.forget(aClone);
+  return NS_OK;
+}