Make PacketReader/PacketWriter interfaces async-only.

blimp/net/blimp_message_pump.cc

Index: blimp/net/blimp_message_pump.cc
diff --git a/blimp/net/blimp_message_pump.cc b/blimp/net/blimp_message_pump.cc
index 14d8d2eec875d712d06741ff198a333ac99d4460..8aef21ae2990bbd48f77169447798e1265e390c7 100644
--- a/blimp/net/blimp_message_pump.cc
+++ b/blimp/net/blimp_message_pump.cc
@@ -40,20 +40,15 @@ void BlimpMessagePump::ReadNextPacket() {
   buffer_->set_offset(0);
   read_packet_callback_.Reset(base::Bind(
       &BlimpMessagePump::OnReadPacketComplete, base::Unretained(this)));
-  int result =
-      reader_->ReadPacket(buffer_.get(), read_packet_callback_.callback());
-  if (result != net::ERR_IO_PENDING) {
-    // Read completed synchronously.
-    OnReadPacketComplete(result);
-  }
+  reader_->ReadPacket(buffer_.get(), read_packet_callback_.callback());
 }
 
 void BlimpMessagePump::OnReadPacketComplete(int result) {
-  if (result > 0) {
+  if (result == net::OK) {
     // The result is the size of the packet in bytes.

[haibinlu, 2015/11/25 19:10:33]

so, ReadPacket no longer returns the size of the packet in bytes on success? 

update PacketReader.ReadPacket description.

[Kevin M, 2015/11/30 19:25:14]

The interface was changed in response to feedback for this CL. We will use the
buffer's offset to communicate the size to callers.

PacketReader.ReadPacket() comment is already up-to-date.

     scoped_ptr<BlimpMessage> message(new BlimpMessage);
     bool parse_result =
-        message->ParseFromArray(buffer_->StartOfBuffer(), result);
+        message->ParseFromArray(buffer_->StartOfBuffer(), buffer_->offset());
     if (parse_result) {
       process_msg_callback_.Reset(base::Bind(
           &BlimpMessagePump::OnProcessMessageComplete, base::Unretained(this)));
@@ -63,6 +58,9 @@ void BlimpMessagePump::OnReadPacketComplete(int result) {
     }
     result = net::ERR_FAILED;
   }
+
+  // Error reporting.
+  DCHECK_NE(net::OK, result);

[haibinlu, 2015/11/25 19:10:33]

is this obviously true?

[Kevin M, 2015/11/30 19:25:14]

Yes - the only success case returns out of the function.

I added an "else" before setting net::ERR_FAILED to make this more explicit.

   if (error_observer_)
     error_observer_->OnConnectionError(result);
 }