net/quic/quic_packet_reader.cc

   1 // Copyright (c) 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/quic/quic_packet_reader.h"
   6
   7 #include "base/metrics/histogram.h"
   8 #include "net/base/net_errors.h"
   9
  10 namespace net {
  11
  12 QuicPacketReader::QuicPacketReader(DatagramClientSocket* socket,
  13                                    Visitor* visitor,
  14                                    const BoundNetLog& net_log)
  15     : socket_(socket),
  16       visitor_(visitor),
  17       read_pending_(false),
  18       num_packets_read_(0),
  19       read_buffer_(new IOBufferWithSize(kMaxPacketSize)),
  20       net_log_(net_log),
  21       weak_factory_(this) {
  22 }
  23
  24 QuicPacketReader::~QuicPacketReader() {
  25 }
  26
  27 void QuicPacketReader::StartReading() {
  28   if (read_pending_)
  29     return;
  30
  31   DCHECK(socket_);
  32   read_pending_ = true;
  33   int rv = socket_->Read(read_buffer_.get(), read_buffer_->size(),
  34                          base::Bind(&QuicPacketReader::OnReadComplete,
  35                                     weak_factory_.GetWeakPtr()));
  36   UMA_HISTOGRAM_BOOLEAN("Net.QuicSession.AsyncRead", rv == ERR_IO_PENDING);
  37   if (rv == ERR_IO_PENDING) {
  38     num_packets_read_ = 0;
  39     return;
  40   }
  41
  42   if (++num_packets_read_ > 32) {
  43     num_packets_read_ = 0;
  44     // Data was read, process it.
  45     // Schedule the work through the message loop to 1) prevent infinite
  46     // recursion and 2) avoid blocking the thread for too long.
  47     base::MessageLoop::current()->PostTask(
  48         FROM_HERE, base::Bind(&QuicPacketReader::OnReadComplete,
  49                               weak_factory_.GetWeakPtr(), rv));
  50   } else {
  51     OnReadComplete(rv);
  52   }
  53 }
  54
  55 void QuicPacketReader::OnReadComplete(int result) {
  56   read_pending_ = false;
  57   if (result == 0)
  58     result = ERR_CONNECTION_CLOSED;
  59
  60   if (result < 0) {
  61     visitor_->OnReadError(result);
  62     return;
  63   }
  64
  65   QuicEncryptedPacket packet(read_buffer_->data(), result);
  66   IPEndPoint local_address;
  67   IPEndPoint peer_address;
  68   socket_->GetLocalAddress(&local_address);
  69   socket_->GetPeerAddress(&peer_address);
  70   if (!visitor_->OnPacket(packet, local_address, peer_address))
  71     return;
  72
  73   StartReading();
  74 }
  75
  76 }  // namespace net