Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 741 insertions, 0 deletions

diff --git a/ipc/glue/DataPipe.cpp b/ipc/glue/DataPipe.cpp
new file mode 100644
index 0000000000..55e38ddd67
--- /dev/null
+++ b/ipc/glue/DataPipe.cpp
@@ -0,0 +1,741 @@
+/* -*- 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/. */
+
+#include "DataPipe.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/CheckedInt.h"
+#include "mozilla/ErrorNames.h"
+#include "mozilla/Logging.h"
+#include "mozilla/MoveOnlyFunction.h"
+#include "mozilla/ipc/InputStreamParams.h"
+#include "nsIAsyncInputStream.h"
+#include "nsStreamUtils.h"
+#include "nsThreadUtils.h"
+
+namespace mozilla {
+namespace ipc {
+
+LazyLogModule gDataPipeLog("DataPipe");
+
+namespace data_pipe_detail {
+
+// Helper for queueing up actions to be run once the mutex has been unlocked.
+// Actions will be run in-order.
+class MOZ_SCOPED_CAPABILITY DataPipeAutoLock {
+ public:
+  explicit DataPipeAutoLock(Mutex& aMutex) MOZ_CAPABILITY_ACQUIRE(aMutex)
+      : mMutex(aMutex) {
+    mMutex.Lock();
+  }
+  DataPipeAutoLock(const DataPipeAutoLock&) = delete;
+  DataPipeAutoLock& operator=(const DataPipeAutoLock&) = delete;
+
+  template <typename F>
+  void AddUnlockAction(F aAction) {
+    mActions.AppendElement(std::move(aAction));
+  }
+
+  ~DataPipeAutoLock() MOZ_CAPABILITY_RELEASE() {
+    mMutex.Unlock();
+    for (auto& action : mActions) {
+      action();
+    }
+  }
+
+ private:
+  Mutex& mMutex;
+  AutoTArray<MoveOnlyFunction<void()>, 4> mActions;
+};
+
+static void DoNotifyOnUnlock(DataPipeAutoLock& aLock,
+                             already_AddRefed<nsIRunnable> aCallback,
+                             already_AddRefed<nsIEventTarget> aTarget) {
+  nsCOMPtr<nsIRunnable> callback{std::move(aCallback)};
+  nsCOMPtr<nsIEventTarget> target{std::move(aTarget)};
+  if (callback) {
+    aLock.AddUnlockAction(
+        [callback = std::move(callback), target = std::move(target)]() mutable {
+          if (target) {
+            target->Dispatch(callback.forget());
+          } else {
+            NS_DispatchBackgroundTask(callback.forget());
+          }
+        });
+  }
+}
+
+class DataPipeLink : public NodeController::PortObserver {
+ public:
+  DataPipeLink(bool aReceiverSide, std::shared_ptr<Mutex> aMutex,
+               ScopedPort aPort, SharedMemory* aShmem, uint32_t aCapacity,
+               nsresult aPeerStatus, uint32_t aOffset, uint32_t aAvailable)
+      : mMutex(std::move(aMutex)),
+        mPort(std::move(aPort)),
+        mShmem(aShmem),
+        mCapacity(aCapacity),
+        mReceiverSide(aReceiverSide),
+        mPeerStatus(aPeerStatus),
+        mOffset(aOffset),
+        mAvailable(aAvailable) {}
+
+  void Init() MOZ_EXCLUDES(*mMutex) {
+    {
+      DataPipeAutoLock lock(*mMutex);
+      if (NS_FAILED(mPeerStatus)) {
+        return;
+      }
+      MOZ_ASSERT(mPort.IsValid());
+      mPort.Controller()->SetPortObserver(mPort.Port(), this);
+    }
+    OnPortStatusChanged();
+  }
+
+  void OnPortStatusChanged() final MOZ_EXCLUDES(*mMutex);
+
+  // Add a task to notify the callback after `aLock` is unlocked.
+  //
+  // This method is safe to call multiple times, as after the first time it is
+  // called, `mCallback` will be cleared.
+  void NotifyOnUnlock(DataPipeAutoLock& aLock) MOZ_REQUIRES(*mMutex) {
+    DoNotifyOnUnlock(aLock, mCallback.forget(), mCallbackTarget.forget());
+  }
+
+  void SendBytesConsumedOnUnlock(DataPipeAutoLock& aLock, uint32_t aBytes)
+      MOZ_REQUIRES(*mMutex) {
+    MOZ_LOG(gDataPipeLog, LogLevel::Verbose,
+            ("SendOnUnlock CONSUMED(%u) %s", aBytes, Describe(aLock).get()));
+    if (NS_FAILED(mPeerStatus)) {
+      return;
+    }
+
+    // `mPort` may be destroyed by `SetPeerError` after the DataPipe is unlocked
+    // but before we send the message. The strong controller and port references
+    // will allow us to try to send the message anyway, and it will be safely
+    // dropped if the port has already been closed. CONSUMED messages are safe
+    // to deliver out-of-order, so we don't need to worry about ordering here.
+    aLock.AddUnlockAction([controller = RefPtr{mPort.Controller()},
+                           port = mPort.Port(), aBytes]() mutable {
+      auto message = MakeUnique<IPC::Message>(
+          MSG_ROUTING_NONE, DATA_PIPE_BYTES_CONSUMED_MESSAGE_TYPE);
+      IPC::MessageWriter writer(*message);
+      WriteParam(&writer, aBytes);
+      controller->SendUserMessage(port, std::move(message));
+    });
+  }
+
+  void SetPeerError(DataPipeAutoLock& aLock, nsresult aStatus,
+                    bool aSendClosed = false) MOZ_REQUIRES(*mMutex) {
+    MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+            ("SetPeerError(%s%s) %s", GetStaticErrorName(aStatus),
+             aSendClosed ? ", send" : "", Describe(aLock).get()));
+    // The pipe was closed or errored. Clear the observer reference back
+    // to this type from the port layer, and ensure we notify waiters.
+    MOZ_ASSERT(NS_SUCCEEDED(mPeerStatus));
+    mPeerStatus = NS_SUCCEEDED(aStatus) ? NS_BASE_STREAM_CLOSED : aStatus;
+    aLock.AddUnlockAction([port = std::move(mPort), aStatus, aSendClosed] {
+      if (aSendClosed) {
+        auto message = MakeUnique<IPC::Message>(MSG_ROUTING_NONE,
+                                                DATA_PIPE_CLOSED_MESSAGE_TYPE);
+        IPC::MessageWriter writer(*message);
+        WriteParam(&writer, aStatus);
+        port.Controller()->SendUserMessage(port.Port(), std::move(message));
+      }
+      // The `ScopedPort` being destroyed with this action will close it,
+      // clearing the observer reference from the ports layer.
+    });
+    NotifyOnUnlock(aLock);
+  }
+
+  nsCString Describe(DataPipeAutoLock& aLock) const MOZ_REQUIRES(*mMutex) {
+    return nsPrintfCString(
+        "[%s(%p) c=%u e=%s o=%u a=%u, cb=%s]",
+        mReceiverSide ? "Receiver" : "Sender", this, mCapacity,
+        GetStaticErrorName(mPeerStatus), mOffset, mAvailable,
+        mCallback ? (mCallbackClosureOnly ? "clo" : "yes") : "no");
+  }
+
+  // This mutex is shared with the `DataPipeBase` which owns this
+  // `DataPipeLink`.
+  std::shared_ptr<Mutex> mMutex;
+
+  ScopedPort mPort MOZ_GUARDED_BY(*mMutex);
+  const RefPtr<SharedMemory> mShmem;
+  const uint32_t mCapacity;
+  const bool mReceiverSide;
+
+  bool mProcessingSegment MOZ_GUARDED_BY(*mMutex) = false;
+
+  nsresult mPeerStatus MOZ_GUARDED_BY(*mMutex) = NS_OK;
+  uint32_t mOffset MOZ_GUARDED_BY(*mMutex) = 0;
+  uint32_t mAvailable MOZ_GUARDED_BY(*mMutex) = 0;
+
+  bool mCallbackClosureOnly MOZ_GUARDED_BY(*mMutex) = false;
+  nsCOMPtr<nsIRunnable> mCallback MOZ_GUARDED_BY(*mMutex);
+  nsCOMPtr<nsIEventTarget> mCallbackTarget MOZ_GUARDED_BY(*mMutex);
+};
+
+void DataPipeLink::OnPortStatusChanged() {
+  DataPipeAutoLock lock(*mMutex);
+
+  while (NS_SUCCEEDED(mPeerStatus)) {
+    UniquePtr<IPC::Message> message;
+    if (!mPort.Controller()->GetMessage(mPort.Port(), &message)) {
+      SetPeerError(lock, NS_BASE_STREAM_CLOSED);
+      return;
+    }
+    if (!message) {
+      return;  // no more messages
+    }
+
+    IPC::MessageReader reader(*message);
+    switch (message->type()) {
+      case DATA_PIPE_CLOSED_MESSAGE_TYPE: {
+        nsresult status = NS_OK;
+        if (!ReadParam(&reader, &status)) {
+          NS_WARNING("Unable to parse nsresult error from peer");
+          status = NS_ERROR_UNEXPECTED;
+        }
+        MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+                ("Got CLOSED(%s) %s", GetStaticErrorName(status),
+                 Describe(lock).get()));
+        SetPeerError(lock, status);
+        return;
+      }
+      case DATA_PIPE_BYTES_CONSUMED_MESSAGE_TYPE: {
+        uint32_t consumed = 0;
+        if (!ReadParam(&reader, &consumed)) {
+          NS_WARNING("Unable to parse bytes consumed from peer");
+          SetPeerError(lock, NS_ERROR_UNEXPECTED);
+          return;
+        }
+
+        MOZ_LOG(gDataPipeLog, LogLevel::Verbose,
+                ("Got CONSUMED(%u) %s", consumed, Describe(lock).get()));
+        auto newAvailable = CheckedUint32{mAvailable} + consumed;
+        if (!newAvailable.isValid() || newAvailable.value() > mCapacity) {
+          NS_WARNING("Illegal bytes consumed message received from peer");
+          SetPeerError(lock, NS_ERROR_UNEXPECTED);
+          return;
+        }
+        mAvailable = newAvailable.value();
+        if (!mCallbackClosureOnly) {
+          NotifyOnUnlock(lock);
+        }
+        break;
+      }
+      default: {
+        NS_WARNING("Illegal message type received from peer");
+        SetPeerError(lock, NS_ERROR_UNEXPECTED);
+        return;
+      }
+    }
+  }
+}
+
+DataPipeBase::DataPipeBase(bool aReceiverSide, nsresult aError)
+    : mMutex(std::make_shared<Mutex>(aReceiverSide ? "DataPipeReceiver"
+                                                   : "DataPipeSender")),
+      mStatus(NS_SUCCEEDED(aError) ? NS_BASE_STREAM_CLOSED : aError) {}
+
+DataPipeBase::DataPipeBase(bool aReceiverSide, ScopedPort aPort,
+                           SharedMemory* aShmem, uint32_t aCapacity,
+                           nsresult aPeerStatus, uint32_t aOffset,
+                           uint32_t aAvailable)
+    : mMutex(std::make_shared<Mutex>(aReceiverSide ? "DataPipeReceiver"
+                                                   : "DataPipeSender")),
+      mStatus(NS_OK),
+      mLink(new DataPipeLink(aReceiverSide, mMutex, std::move(aPort), aShmem,
+                             aCapacity, aPeerStatus, aOffset, aAvailable)) {
+  mLink->Init();
+}
+
+DataPipeBase::~DataPipeBase() {
+  DataPipeAutoLock lock(*mMutex);
+  CloseInternal(lock, NS_BASE_STREAM_CLOSED);
+}
+
+void DataPipeBase::CloseInternal(DataPipeAutoLock& aLock, nsresult aStatus) {
+  if (NS_FAILED(mStatus)) {
+    return;
+  }
+
+  MOZ_LOG(
+      gDataPipeLog, LogLevel::Debug,
+      ("Closing(%s) %s", GetStaticErrorName(aStatus), Describe(aLock).get()));
+
+  // Set our status to an errored status.
+  mStatus = NS_SUCCEEDED(aStatus) ? NS_BASE_STREAM_CLOSED : aStatus;
+  RefPtr<DataPipeLink> link = mLink.forget();
+  AssertSameMutex(link->mMutex);
+  link->NotifyOnUnlock(aLock);
+
+  // If our peer hasn't disappeared yet, clean up our connection to it.
+  if (NS_SUCCEEDED(link->mPeerStatus)) {
+    link->SetPeerError(aLock, mStatus, /* aSendClosed */ true);
+  }
+}
+
+nsresult DataPipeBase::ProcessSegmentsInternal(
+    uint32_t aCount, ProcessSegmentFun aProcessSegment,
+    uint32_t* aProcessedCount) {
+  *aProcessedCount = 0;
+
+  while (*aProcessedCount < aCount) {
+    DataPipeAutoLock lock(*mMutex);
+    mMutex->AssertCurrentThreadOwns();
+
+    MOZ_LOG(gDataPipeLog, LogLevel::Verbose,
+            ("ProcessSegments(%u of %u) %s", *aProcessedCount, aCount,
+             Describe(lock).get()));
+
+    nsresult status = CheckStatus(lock);
+    if (NS_FAILED(status)) {
+      if (*aProcessedCount > 0) {
+        return NS_OK;
+      }
+      return status == NS_BASE_STREAM_CLOSED ? NS_OK : status;
+    }
+
+    RefPtr<DataPipeLink> link = mLink;
+    AssertSameMutex(link->mMutex);
+    if (!link->mAvailable) {
+      MOZ_DIAGNOSTIC_ASSERT(NS_SUCCEEDED(link->mPeerStatus),
+                            "CheckStatus will have returned an error");
+      return *aProcessedCount > 0 ? NS_OK : NS_BASE_STREAM_WOULD_BLOCK;
+    }
+
+    MOZ_RELEASE_ASSERT(!link->mProcessingSegment,
+                       "Only one thread may be processing a segment at a time");
+
+    // Extract an iterator over the next contiguous region of the shared memory
+    // buffer which will be used .
+    char* start = static_cast<char*>(link->mShmem->memory()) + link->mOffset;
+    char* iter = start;
+    char* end = start + std::min({aCount - *aProcessedCount, link->mAvailable,
+                                  link->mCapacity - link->mOffset});
+
+    // Record the consumed region from our segment when exiting this scope,
+    // telling our peer how many bytes were consumed. Hold on to `mLink` to keep
+    // the shmem mapped and make sure we can clean up even if we're closed while
+    // processing the shmem region.
+    link->mProcessingSegment = true;
+    auto scopeExit = MakeScopeExit([&] {
+      mMutex->AssertCurrentThreadOwns();  // should still be held
+      AssertSameMutex(link->mMutex);
+
+      MOZ_RELEASE_ASSERT(link->mProcessingSegment);
+      link->mProcessingSegment = false;
+      uint32_t totalProcessed = iter - start;
+      if (totalProcessed > 0) {
+        link->mOffset += totalProcessed;
+        MOZ_RELEASE_ASSERT(link->mOffset <= link->mCapacity);
+        if (link->mOffset == link->mCapacity) {
+          link->mOffset = 0;
+        }
+        link->mAvailable -= totalProcessed;
+        link->SendBytesConsumedOnUnlock(lock, totalProcessed);
+      }
+      MOZ_LOG(gDataPipeLog, LogLevel::Verbose,
+              ("Processed Segment(%u of %zu) %s", totalProcessed, end - start,
+               Describe(lock).get()));
+    });
+
+    {
+      MutexAutoUnlock unlock(*mMutex);
+      while (iter < end) {
+        uint32_t processed = 0;
+        Span segment{iter, end};
+        nsresult rv = aProcessSegment(segment, *aProcessedCount, &processed);
+        if (NS_FAILED(rv) || processed == 0) {
+          return NS_OK;
+        }
+
+        MOZ_RELEASE_ASSERT(processed <= segment.Length());
+        iter += processed;
+        *aProcessedCount += processed;
+      }
+    }
+  }
+  MOZ_DIAGNOSTIC_ASSERT(*aProcessedCount == aCount,
+                        "Must have processed exactly aCount");
+  return NS_OK;
+}
+
+void DataPipeBase::AsyncWaitInternal(already_AddRefed<nsIRunnable> aCallback,
+                                     already_AddRefed<nsIEventTarget> aTarget,
+                                     bool aClosureOnly) {
+  RefPtr<nsIRunnable> callback = std::move(aCallback);
+  RefPtr<nsIEventTarget> target = std::move(aTarget);
+
+  DataPipeAutoLock lock(*mMutex);
+  MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+          ("AsyncWait %s %p %s", aClosureOnly ? "(closure)" : "(ready)",
+           callback.get(), Describe(lock).get()));
+
+  if (NS_FAILED(CheckStatus(lock))) {
+#ifdef DEBUG
+    if (mLink) {
+      AssertSameMutex(mLink->mMutex);
+      MOZ_ASSERT(!mLink->mCallback);
+    }
+#endif
+    DoNotifyOnUnlock(lock, callback.forget(), target.forget());
+    return;
+  }
+
+  AssertSameMutex(mLink->mMutex);
+
+  // NOTE: After this point, `mLink` may have previously had a callback which is
+  // now being cancelled, make sure we clear `mCallback` even if we're going to
+  // call `aCallback` immediately.
+  mLink->mCallback = callback.forget();
+  mLink->mCallbackTarget = target.forget();
+  mLink->mCallbackClosureOnly = aClosureOnly;
+  if (!aClosureOnly && mLink->mAvailable) {
+    mLink->NotifyOnUnlock(lock);
+  }
+}
+
+nsresult DataPipeBase::CheckStatus(DataPipeAutoLock& aLock) {
+  // If our peer has closed or errored, we may need to close our local side to
+  // reflect the error code our peer provided. If we're a sender, we want to
+  // become closed immediately, whereas if we're a receiver we want to wait
+  // until our available buffer has been exhausted.
+  //
+  // NOTE: There may still be 2-stage writes/reads ongoing at this point, which
+  // will continue due to `mLink` being kept alive by the
+  // `ProcessSegmentsInternal` function.
+  if (NS_FAILED(mStatus)) {
+    return mStatus;
+  }
+  AssertSameMutex(mLink->mMutex);
+  if (NS_FAILED(mLink->mPeerStatus) &&
+      (!mLink->mReceiverSide || !mLink->mAvailable)) {
+    CloseInternal(aLock, mLink->mPeerStatus);
+  }
+  return mStatus;
+}
+
+nsCString DataPipeBase::Describe(DataPipeAutoLock& aLock) {
+  if (mLink) {
+    AssertSameMutex(mLink->mMutex);
+    return mLink->Describe(aLock);
+  }
+  return nsPrintfCString("[status=%s]", GetStaticErrorName(mStatus));
+}
+
+template <typename T>
+void DataPipeWrite(IPC::MessageWriter* aWriter, T* aParam) {
+  DataPipeAutoLock lock(*aParam->mMutex);
+  MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+          ("IPC Write: %s", aParam->Describe(lock).get()));
+
+  WriteParam(aWriter, aParam->mStatus);
+  if (NS_FAILED(aParam->mStatus)) {
+    return;
+  }
+
+  aParam->AssertSameMutex(aParam->mLink->mMutex);
+  MOZ_RELEASE_ASSERT(!aParam->mLink->mProcessingSegment,
+                     "cannot transfer while processing a segment");
+
+  // Serialize relevant parameters to our peer.
+  WriteParam(aWriter, std::move(aParam->mLink->mPort));
+  if (!aParam->mLink->mShmem->WriteHandle(aWriter)) {
+    aWriter->FatalError("failed to write DataPipe shmem handle");
+    MOZ_CRASH("failed to write DataPipe shmem handle");
+  }
+  WriteParam(aWriter, aParam->mLink->mCapacity);
+  WriteParam(aWriter, aParam->mLink->mPeerStatus);
+  WriteParam(aWriter, aParam->mLink->mOffset);
+  WriteParam(aWriter, aParam->mLink->mAvailable);
+
+  // Mark our peer as closed so we don't try to send to it when closing.
+  aParam->mLink->mPeerStatus = NS_ERROR_NOT_INITIALIZED;
+  aParam->CloseInternal(lock, NS_ERROR_NOT_INITIALIZED);
+}
+
+template <typename T>
+bool DataPipeRead(IPC::MessageReader* aReader, RefPtr<T>* aResult) {
+  nsresult rv = NS_OK;
+  if (!ReadParam(aReader, &rv)) {
+    aReader->FatalError("failed to read DataPipe status");
+    return false;
+  }
+  if (NS_FAILED(rv)) {
+    *aResult = new T(rv);
+    MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+            ("IPC Read: [status=%s]", GetStaticErrorName(rv)));
+    return true;
+  }
+
+  ScopedPort port;
+  if (!ReadParam(aReader, &port)) {
+    aReader->FatalError("failed to read DataPipe port");
+    return false;
+  }
+  RefPtr shmem = new SharedMemoryBasic();
+  if (!shmem->ReadHandle(aReader)) {
+    aReader->FatalError("failed to read DataPipe shmem");
+    return false;
+  }
+  uint32_t capacity = 0;
+  nsresult peerStatus = NS_OK;
+  uint32_t offset = 0;
+  uint32_t available = 0;
+  if (!ReadParam(aReader, &capacity) || !ReadParam(aReader, &peerStatus) ||
+      !ReadParam(aReader, &offset) || !ReadParam(aReader, &available)) {
+    aReader->FatalError("failed to read DataPipe fields");
+    return false;
+  }
+  if (!capacity || offset >= capacity || available > capacity) {
+    aReader->FatalError("received DataPipe state values are inconsistent");
+    return false;
+  }
+  if (!shmem->Map(SharedMemory::PageAlignedSize(capacity))) {
+    aReader->FatalError("failed to map DataPipe shared memory region");
+    return false;
+  }
+
+  *aResult =
+      new T(std::move(port), shmem, capacity, peerStatus, offset, available);
+  if (MOZ_LOG_TEST(gDataPipeLog, LogLevel::Debug)) {
+    DataPipeAutoLock lock(*(*aResult)->mMutex);
+    MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+            ("IPC Read: %s", (*aResult)->Describe(lock).get()));
+  }
+  return true;
+}
+
+}  // namespace data_pipe_detail
+
+//-----------------------------------------------------------------------------
+// DataPipeSender
+//-----------------------------------------------------------------------------
+
+NS_IMPL_ISUPPORTS(DataPipeSender, nsIOutputStream, nsIAsyncOutputStream,
+                  DataPipeSender)
+
+// nsIOutputStream
+
+NS_IMETHODIMP DataPipeSender::Close() {
+  return CloseWithStatus(NS_BASE_STREAM_CLOSED);
+}
+
+NS_IMETHODIMP DataPipeSender::Flush() { return NS_OK; }
+
+NS_IMETHODIMP DataPipeSender::StreamStatus() {
+  data_pipe_detail::DataPipeAutoLock lock(*mMutex);
+  return CheckStatus(lock);
+}
+
+NS_IMETHODIMP DataPipeSender::Write(const char* aBuf, uint32_t aCount,
+                                    uint32_t* aWriteCount) {
+  return WriteSegments(NS_CopyBufferToSegment, (void*)aBuf, aCount,
+                       aWriteCount);
+}
+
+NS_IMETHODIMP DataPipeSender::WriteFrom(nsIInputStream* aFromStream,
+                                        uint32_t aCount,
+                                        uint32_t* aWriteCount) {
+  return WriteSegments(NS_CopyStreamToSegment, aFromStream, aCount,
+                       aWriteCount);
+}
+
+NS_IMETHODIMP DataPipeSender::WriteSegments(nsReadSegmentFun aReader,
+                                            void* aClosure, uint32_t aCount,
+                                            uint32_t* aWriteCount) {
+  auto processSegment = [&](Span<char> aSpan, uint32_t aToOffset,
+                            uint32_t* aReadCount) -> nsresult {
+    return aReader(this, aClosure, aSpan.data(), aToOffset, aSpan.Length(),
+                   aReadCount);
+  };
+  return ProcessSegmentsInternal(aCount, processSegment, aWriteCount);
+}
+
+NS_IMETHODIMP DataPipeSender::IsNonBlocking(bool* _retval) {
+  *_retval = true;
+  return NS_OK;
+}
+
+// nsIAsyncOutputStream
+
+NS_IMETHODIMP DataPipeSender::CloseWithStatus(nsresult reason) {
+  data_pipe_detail::DataPipeAutoLock lock(*mMutex);
+  CloseInternal(lock, reason);
+  return NS_OK;
+}
+
+NS_IMETHODIMP DataPipeSender::AsyncWait(nsIOutputStreamCallback* aCallback,
+                                        uint32_t aFlags,
+                                        uint32_t aRequestedCount,
+                                        nsIEventTarget* aTarget) {
+  AsyncWaitInternal(
+      aCallback ? NS_NewCancelableRunnableFunction(
+                      "DataPipeReceiver::AsyncWait",
+                      [self = RefPtr{this}, callback = RefPtr{aCallback}] {
+                        MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+                                ("Calling OnOutputStreamReady(%p, %p)",
+                                 callback.get(), self.get()));
+                        callback->OnOutputStreamReady(self);
+                      })
+                : nullptr,
+      do_AddRef(aTarget), aFlags & WAIT_CLOSURE_ONLY);
+  return NS_OK;
+}
+
+//-----------------------------------------------------------------------------
+// DataPipeReceiver
+//-----------------------------------------------------------------------------
+
+NS_IMPL_ISUPPORTS(DataPipeReceiver, nsIInputStream, nsIAsyncInputStream,
+                  nsIIPCSerializableInputStream, DataPipeReceiver)
+
+// nsIInputStream
+
+NS_IMETHODIMP DataPipeReceiver::Close() {
+  return CloseWithStatus(NS_BASE_STREAM_CLOSED);
+}
+
+NS_IMETHODIMP DataPipeReceiver::Available(uint64_t* _retval) {
+  data_pipe_detail::DataPipeAutoLock lock(*mMutex);
+  nsresult rv = CheckStatus(lock);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+  AssertSameMutex(mLink->mMutex);
+  *_retval = mLink->mAvailable;
+  return NS_OK;
+}
+
+NS_IMETHODIMP DataPipeReceiver::StreamStatus() {
+  data_pipe_detail::DataPipeAutoLock lock(*mMutex);
+  return CheckStatus(lock);
+}
+
+NS_IMETHODIMP DataPipeReceiver::Read(char* aBuf, uint32_t aCount,
+                                     uint32_t* aReadCount) {
+  return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aReadCount);
+}
+
+NS_IMETHODIMP DataPipeReceiver::ReadSegments(nsWriteSegmentFun aWriter,
+                                             void* aClosure, uint32_t aCount,
+                                             uint32_t* aReadCount) {
+  auto processSegment = [&](Span<char> aSpan, uint32_t aToOffset,
+                            uint32_t* aWriteCount) -> nsresult {
+    return aWriter(this, aClosure, aSpan.data(), aToOffset, aSpan.Length(),
+                   aWriteCount);
+  };
+  return ProcessSegmentsInternal(aCount, processSegment, aReadCount);
+}
+
+NS_IMETHODIMP DataPipeReceiver::IsNonBlocking(bool* _retval) {
+  *_retval = true;
+  return NS_OK;
+}
+
+// nsIAsyncInputStream
+
+NS_IMETHODIMP DataPipeReceiver::CloseWithStatus(nsresult aStatus) {
+  data_pipe_detail::DataPipeAutoLock lock(*mMutex);
+  CloseInternal(lock, aStatus);
+  return NS_OK;
+}
+
+NS_IMETHODIMP DataPipeReceiver::AsyncWait(nsIInputStreamCallback* aCallback,
+                                          uint32_t aFlags,
+                                          uint32_t aRequestedCount,
+                                          nsIEventTarget* aTarget) {
+  AsyncWaitInternal(
+      aCallback ? NS_NewCancelableRunnableFunction(
+                      "DataPipeReceiver::AsyncWait",
+                      [self = RefPtr{this}, callback = RefPtr{aCallback}] {
+                        MOZ_LOG(gDataPipeLog, LogLevel::Debug,
+                                ("Calling OnInputStreamReady(%p, %p)",
+                                 callback.get(), self.get()));
+                        callback->OnInputStreamReady(self);
+                      })
+                : nullptr,
+      do_AddRef(aTarget), aFlags & WAIT_CLOSURE_ONLY);
+  return NS_OK;
+}
+
+// nsIIPCSerializableInputStream
+
+void DataPipeReceiver::SerializedComplexity(uint32_t aMaxSize,
+                                            uint32_t* aSizeUsed,
+                                            uint32_t* aPipes,
+                                            uint32_t* aTransferables) {
+  // We report DataPipeReceiver as taking one transferrable to serialize, rather
+  // than one pipe, as we aren't starting a new pipe for this purpose, and are
+  // instead transferring an existing pipe.
+  *aTransferables = 1;
+}
+
+void DataPipeReceiver::Serialize(InputStreamParams& aParams, uint32_t aMaxSize,
+                                 uint32_t* aSizeUsed) {
+  *aSizeUsed = 0;
+  aParams = DataPipeReceiverStreamParams(this);
+}
+
+bool DataPipeReceiver::Deserialize(const InputStreamParams& aParams) {
+  MOZ_CRASH("Handled directly in `DeserializeInputStream`");
+}
+
+//-----------------------------------------------------------------------------
+// NewDataPipe
+//-----------------------------------------------------------------------------
+
+nsresult NewDataPipe(uint32_t aCapacity, DataPipeSender** aSender,
+                     DataPipeReceiver** aReceiver) {
+  if (!aCapacity) {
+    aCapacity = kDefaultDataPipeCapacity;
+  }
+
+  RefPtr<NodeController> controller = NodeController::GetSingleton();
+  if (!controller) {
+    return NS_ERROR_ILLEGAL_DURING_SHUTDOWN;
+  }
+
+  auto [senderPort, receiverPort] = controller->CreatePortPair();
+  auto shmem = MakeRefPtr<SharedMemoryBasic>();
+  size_t alignedCapacity = SharedMemory::PageAlignedSize(aCapacity);
+  if (!shmem->Create(alignedCapacity) || !shmem->Map(alignedCapacity)) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  RefPtr sender = new DataPipeSender(std::move(senderPort), shmem, aCapacity,
+                                     NS_OK, 0, aCapacity);
+  RefPtr receiver = new DataPipeReceiver(std::move(receiverPort), shmem,
+                                         aCapacity, NS_OK, 0, 0);
+  sender.forget(aSender);
+  receiver.forget(aReceiver);
+  return NS_OK;
+}
+
+}  // namespace ipc
+}  // namespace mozilla
+
+void IPC::ParamTraits<mozilla::ipc::DataPipeSender*>::Write(
+    MessageWriter* aWriter, mozilla::ipc::DataPipeSender* aParam) {
+  mozilla::ipc::data_pipe_detail::DataPipeWrite(aWriter, aParam);
+}
+
+bool IPC::ParamTraits<mozilla::ipc::DataPipeSender*>::Read(
+    MessageReader* aReader, RefPtr<mozilla::ipc::DataPipeSender>* aResult) {
+  return mozilla::ipc::data_pipe_detail::DataPipeRead(aReader, aResult);
+}
+
+void IPC::ParamTraits<mozilla::ipc::DataPipeReceiver*>::Write(
+    MessageWriter* aWriter, mozilla::ipc::DataPipeReceiver* aParam) {
+  mozilla::ipc::data_pipe_detail::DataPipeWrite(aWriter, aParam);
+}
+
+bool IPC::ParamTraits<mozilla::ipc::DataPipeReceiver*>::Read(
+    MessageReader* aReader, RefPtr<mozilla::ipc::DataPipeReceiver>* aResult) {
+  return mozilla::ipc::data_pipe_detail::DataPipeRead(aReader, aResult);
+}