Bug 1046109: Add |SocketIOBase|, r=kyle

|SocketIOBase| is a base class for Socket I/O classes. It's not a
requirement, but provides a number of helpful methods for common
I/O operations on the I/O thread.

ipc/unixsocket/UnixSocket.cpp

@@ -9,11 +9,6 @@
 #include "nsXULAppAPI.h"
 #include <fcntl.h>
 
-#ifdef MOZ_TASK_TRACER
-#include "GeckoTaskTracer.h"
-using namespace mozilla::tasktracer;
-#endif
-
 static const size_t MAX_READ_SIZE = 1 << 16;
 
 namespace mozilla {
@@ -24,12 +19,14 @@ namespace ipc {
 //
 
 class UnixSocketImpl : public UnixSocketWatcher
+                     , protected SocketIOBase
 {
 public:
   UnixSocketImpl(MessageLoop* mIOLoop,
                  UnixSocketConsumer* aConsumer, UnixSocketConnector* aConnector,
                  const nsACString& aAddress)
     : UnixSocketWatcher(mIOLoop)
+    , SocketIOBase(MAX_READ_SIZE)
     , mConsumer(aConsumer)
     , mConnector(aConnector)
     , mShuttingDownOnIOThread(false)
@@ -44,9 +41,9 @@ public:
     MOZ_ASSERT(IsShutdownOnMainThread());
   }
 
-  void QueueWriteData(UnixSocketRawData* aData)
+  void Send(UnixSocketRawData* aData)
   {
-    mOutgoingQ.AppendElement(aData);
+    EnqueueData(aData);
     AddWatchers(WRITE_WATCHER, false);
   }
 
@@ -145,12 +142,6 @@ private:
 
   void FireSocketError();
 
-  /**
-   * Raw data queue. Must be pushed/popped from IO thread only.
-   */
-  typedef nsTArray<UnixSocketRawData* > UnixSocketRawDataQueue;
-  UnixSocketRawDataQueue mOutgoingQ;
-
   /**
    * Connector object used to create the connection we are currently using.
    */
@@ -228,7 +219,7 @@ public:
     UnixSocketImpl* impl = GetImpl();
     MOZ_ASSERT(!impl->IsShutdownOnIOThread());
 
-    impl->QueueWriteData(mData);
+    impl->Send(mData);
   }
 private:
   nsRefPtr<UnixSocketConsumer> mConsumer;
@@ -463,7 +454,7 @@ UnixSocketImpl::OnAccepted(int aFd,
   NS_DispatchToMainThread(r);
 
   AddWatchers(READ_WATCHER, true);
-  if (!mOutgoingQ.IsEmpty()) {
+  if (HasPendingData()) {
     AddWatchers(WRITE_WATCHER, false);
   }
 }
@@ -492,7 +483,7 @@ UnixSocketImpl::OnConnected()
   NS_DispatchToMainThread(r);
 
   AddWatchers(READ_WATCHER, true);
-  if (!mOutgoingQ.IsEmpty()) {
+  if (HasPendingData()) {
     AddWatchers(WRITE_WATCHER, false);
   }
 }
@@ -527,51 +518,10 @@ UnixSocketImpl::OnSocketCanReceiveWithoutBlocking()
   MOZ_ASSERT(MessageLoopForIO::current() == GetIOLoop());
   MOZ_ASSERT(GetConnectionStatus() == SOCKET_IS_CONNECTED); // see bug 990984
 
-  // Read all of the incoming data.
-  while (true) {
-    nsAutoPtr<UnixSocketRawData> incoming(new UnixSocketRawData(MAX_READ_SIZE));
-
-    ssize_t ret = read(GetFd(), incoming->mData, incoming->mSize);
-    if (ret <= 0) {
-      if (ret == -1) {
-        if (errno == EINTR) {
-          continue; // retry system call when interrupted
-        }
-        if (errno == EAGAIN || errno == EWOULDBLOCK) {
-          return; // no data available: return and re-poll
-        }
-
-#ifdef DEBUG
-        NS_WARNING("Cannot read from network");
-#endif
-        // else fall through to error handling on other errno's
-      }
-
-      // We're done with our descriptors. Ensure that spurious events don't
-      // cause us to end up back here.
-      RemoveWatchers(READ_WATCHER|WRITE_WATCHER);
-      nsRefPtr<nsRunnable> r =
-        new SocketIORequestClosingRunnable<UnixSocketImpl>(this);
-      NS_DispatchToMainThread(r);
-      return;
-    }
-
-#ifdef MOZ_TASK_TRACER
-    // Make unix socket creation events to be the source events of TaskTracer,
-    // and originate the rest correlation tasks from here.
-    AutoSourceEvent taskTracerEvent(SourceEventType::UNIXSOCKET);
-#endif
-
-    incoming->mSize = ret;
-    nsRefPtr<nsRunnable> r =
-      new SocketIOReceiveRunnable<UnixSocketImpl>(this, incoming.forget());
-    NS_DispatchToMainThread(r);
-
-    // If ret is less than MAX_READ_SIZE, there's no
-    // more data in the socket for us to read now.
-    if (ret < ssize_t(MAX_READ_SIZE)) {
-      return;
-    }
+  nsresult rv = ReceiveData(GetFd(), this);
+  if (NS_FAILED(rv)) {
+    RemoveWatchers(READ_WATCHER|WRITE_WATCHER);
+    return;
   }
 }
 
@@ -581,40 +531,13 @@ UnixSocketImpl::OnSocketCanSendWithoutBlocking()
   MOZ_ASSERT(MessageLoopForIO::current() == GetIOLoop());
   MOZ_ASSERT(GetConnectionStatus() == SOCKET_IS_CONNECTED); // see bug 990984
 
-  // Try to write the bytes of mCurrentRilRawData.  If all were written, continue.
-  //
-  // Otherwise, save the byte position of the next byte to write
-  // within mCurrentWriteOffset, and request another write when the
-  // system won't block.
-  //
-  while (true) {
-    UnixSocketRawData* data;
-    if (mOutgoingQ.IsEmpty()) {
-      return;
-    }
-    data = mOutgoingQ.ElementAt(0);
-    const uint8_t *toWrite;
-    toWrite = data->mData;
+  nsresult rv = SendPendingData(GetFd(), this);
+  if (NS_FAILED(rv)) {
+    return;
+  }
 
-    while (data->mCurrentWriteOffset < data->mSize) {
-      ssize_t write_amount = data->mSize - data->mCurrentWriteOffset;
-      ssize_t written;
-      written = write (GetFd(), toWrite + data->mCurrentWriteOffset,
-                         write_amount);
-      if (written > 0) {
-        data->mCurrentWriteOffset += written;
-      }
-      if (written != write_amount) {
-        break;
-      }
-    }
-
-    if (data->mCurrentWriteOffset != data->mSize) {
-      AddWatchers(WRITE_WATCHER, false);
-      return;
-    }
-    mOutgoingQ.RemoveElementAt(0);
-    delete data;
+  if (HasPendingData()) {
+    AddWatchers(WRITE_WATCHER, false);
   }
 }