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/location.h"
   8 #include "base/metrics/histogram_macros.h"
   9 #include "base/single_thread_task_runner.h"
  10 #include "base/thread_task_runner_handle.h"
  11 #include "net/base/net_errors.h"
  12
  13 namespace net {
  14
  15 QuicPacketReader::QuicPacketReader(DatagramClientSocket* socket,
  16                                    Visitor* visitor,
  17                                    const BoundNetLog& net_log)
  18     : socket_(socket),
  19       visitor_(visitor),
  20       read_pending_(false),
  21       num_packets_read_(0),
  22       read_buffer_(new IOBufferWithSize(static_cast<size_t>(kMaxPacketSize))),
  23       net_log_(net_log),
  24       weak_factory_(this) {
  25 }
  26
  27 QuicPacketReader::~QuicPacketReader() {
  28 }
  29
  30 void QuicPacketReader::StartReading() {
  31   if (read_pending_)
  32     return;
  33
  34   DCHECK(socket_);
  35   read_pending_ = true;
  36   int rv = socket_->Read(read_buffer_.get(), read_buffer_->size(),
  37                          base::Bind(&QuicPacketReader::OnReadComplete,
  38                                     weak_factory_.GetWeakPtr()));
  39   UMA_HISTOGRAM_BOOLEAN("Net.QuicSession.AsyncRead", rv == ERR_IO_PENDING);
  40   if (rv == ERR_IO_PENDING) {
  41     num_packets_read_ = 0;
  42     return;
  43   }
  44
  45   if (++num_packets_read_ > 32) {
  46     num_packets_read_ = 0;
  47     // Data was read, process it.
  48     // Schedule the work through the message loop to 1) prevent infinite
  49     // recursion and 2) avoid blocking the thread for too long.
  50     base::ThreadTaskRunnerHandle::Get()->PostTask(
  51         FROM_HERE, base::Bind(&QuicPacketReader::OnReadComplete,
  52                               weak_factory_.GetWeakPtr(), rv));
  53   } else {
  54     OnReadComplete(rv);
  55   }
  56 }
  57
  58 void QuicPacketReader::OnReadComplete(int result) {
  59   read_pending_ = false;
  60   if (result == 0)
  61     result = ERR_CONNECTION_CLOSED;
  62
  63   if (result < 0) {
  64     visitor_->OnReadError(result);
  65     return;
  66   }
  67
  68   QuicEncryptedPacket packet(read_buffer_->data(), result);
  69   IPEndPoint local_address;
  70   IPEndPoint peer_address;
  71   socket_->GetLocalAddress(&local_address);
  72   socket_->GetPeerAddress(&peer_address);
  73   if (!visitor_->OnPacket(packet, local_address, peer_address))
  74     return;
  75
  76   StartReading();
  77 }
  78
  79 }  // namespace net