Make PacketReader/PacketWriter interfaces async-only.

blimp/net/blimp_message_pump.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "blimp/net/blimp_message_pump.h"
 
 #include "base/macros.h"
 #include "blimp/common/proto/blimp_message.pb.h"
 #include "blimp/net/blimp_message_processor.h"
 #include "blimp/net/common.h"
@@ skipping 22 matching lines @@
     buffer_->SetCapacity(kMaxPacketPayloadSizeBytes);
     ReadNextPacket();
   }
 }
 
 void BlimpMessagePump::ReadNextPacket() {
   DCHECK(processor_);
   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)));
       processor_->ProcessMessage(message.Pass(),
                                  process_msg_callback_.callback());
       return;
     }
     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);
 }
 
 void BlimpMessagePump::OnProcessMessageComplete(int result) {
   // No error is expected from the message receiver.
   DCHECK_EQ(result, net::OK);

[Wez, 2015/11/25 02:21:28]

nit: DCHECK_EQ(net::OK, result)

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

Done.

   ReadNextPacket();
 }
 
 }  // namespace blimp