// Copyright 2013 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 "net/socket/tcp_socket_win.h"
#include <mstcpip.h>
#include "base/callback_helpers.h"
#include "base/logging.h"
#include "base/metrics/stats_counters.h"
#include "base/win/windows_version.h"
#include "net/base/address_list.h"
#include "net/base/connection_type_histograms.h"
#include "net/base/io_buffer.h"
#include "net/base/ip_endpoint.h"
#include "net/base/net_errors.h"
#include "net/base/net_util.h"
#include "net/base/network_change_notifier.h"
#include "net/base/winsock_init.h"
#include "net/base/winsock_util.h"
#include "net/socket/socket_descriptor.h"
#include "net/socket/socket_net_log_params.h"
namespace net {
namespace {
const int kTCPKeepAliveSeconds = 45;
bool SetSocketReceiveBufferSize(SOCKET socket, int32 size) {
int rv = setsockopt(socket, SOL_SOCKET, SO_RCVBUF,
reinterpret_cast<const char*>(&size), sizeof(size));
DCHECK(!rv) << "Could not set socket receive buffer size: " << GetLastError();
return rv == 0;
}
bool SetSocketSendBufferSize(SOCKET socket, int32 size) {
int rv = setsockopt(socket, SOL_SOCKET, SO_SNDBUF,
reinterpret_cast<const char*>(&size), sizeof(size));
DCHECK(!rv) << "Could not set socket send buffer size: " << GetLastError();
return rv == 0;
}
// Disable Nagle.
// The Nagle implementation on windows is governed by RFC 896. The idea
// behind Nagle is to reduce small packets on the network. When Nagle is
// enabled, if a partial packet has been sent, the TCP stack will disallow
// further *partial* packets until an ACK has been received from the other
// side. Good applications should always strive to send as much data as
// possible and avoid partial-packet sends. However, in most real world
// applications, there are edge cases where this does not happen, and two
// partial packets may be sent back to back. For a browser, it is NEVER
// a benefit to delay for an RTT before the second packet is sent.
//
// As a practical example in Chromium today, consider the case of a small
// POST. I have verified this:
// Client writes 649 bytes of header (partial packet #1)
// Client writes 50 bytes of POST data (partial packet #2)
// In the above example, with Nagle, a RTT delay is inserted between these
// two sends due to nagle. RTTs can easily be 100ms or more. The best
// fix is to make sure that for POSTing data, we write as much data as
// possible and minimize partial packets. We will fix that. But disabling
// Nagle also ensure we don't run into this delay in other edge cases.
// See also:
// http://technet.microsoft.com/en-us/library/bb726981.aspx
bool DisableNagle(SOCKET socket, bool disable) {
BOOL val = disable ? TRUE : FALSE;
int rv = setsockopt(socket, IPPROTO_TCP, TCP_NODELAY,
reinterpret_cast<const char*>(&val),
sizeof(val));
DCHECK(!rv) << "Could not disable nagle";
return rv == 0;
}
// Enable TCP Keep-Alive to prevent NAT routers from timing out TCP
// connections. See http://crbug.com/27400 for details.
bool SetTCPKeepAlive(SOCKET socket, BOOL enable, int delay_secs) {
int delay = delay_secs * 1000;
struct tcp_keepalive keepalive_vals = {
enable ? 1 : 0, // TCP keep-alive on.
delay, // Delay seconds before sending first TCP keep-alive packet.
delay, // Delay seconds between sending TCP keep-alive packets.
};
DWORD bytes_returned = 0xABAB;
int rv = WSAIoctl(socket, SIO_KEEPALIVE_VALS, &keepalive_vals,
sizeof(keepalive_vals), NULL, 0,
&bytes_returned, NULL, NULL);
DCHECK(!rv) << "Could not enable TCP Keep-Alive for socket: " << socket
<< " [error: " << WSAGetLastError() << "].";
// Disregard any failure in disabling nagle or enabling TCP Keep-Alive.
return rv == 0;
}
int MapConnectError(int os_error) {
switch (os_error) {
// connect fails with WSAEACCES when Windows Firewall blocks the
// connection.
case WSAEACCES:
return ERR_NETWORK_ACCESS_DENIED;
case WSAETIMEDOUT:
return ERR_CONNECTION_TIMED_OUT;
default: {
int net_error = MapSystemError(os_error);
if (net_error == ERR_FAILED)
return ERR_CONNECTION_FAILED; // More specific than ERR_FAILED.
// Give a more specific error when the user is offline.
if (net_error == ERR_ADDRESS_UNREACHABLE &&
NetworkChangeNotifier::IsOffline()) {
return ERR_INTERNET_DISCONNECTED;
}
return net_error;
}
}
}
} // namespace
//-----------------------------------------------------------------------------
// This class encapsulates all the state that has to be preserved as long as
// there is a network IO operation in progress. If the owner TCPSocketWin is
// destroyed while an operation is in progress, the Core is detached and it
// lives until the operation completes and the OS doesn't reference any resource
// declared on this class anymore.
class TCPSocketWin::Core : public base::RefCounted<Core> {
public:
explicit Core(TCPSocketWin* socket);
// Start watching for the end of a read or write operation.
void WatchForRead();
void WatchForWrite();
// The TCPSocketWin is going away.
void Detach() { socket_ = NULL; }
// The separate OVERLAPPED variables for asynchronous operation.
// |read_overlapped_| is used for both Connect() and Read().
// |write_overlapped_| is only used for Write();
OVERLAPPED read_overlapped_;
OVERLAPPED write_overlapped_;
// The buffers used in Read() and Write().
scoped_refptr<IOBuffer> read_iobuffer_;
scoped_refptr<IOBuffer> write_iobuffer_;
int read_buffer_length_;
int write_buffer_length_;
bool non_blocking_reads_initialized_;
private:
friend class base::RefCounted<Core>;
class ReadDelegate : public base::win::ObjectWatcher::Delegate {
public:
explicit ReadDelegate(Core* core) : core_(core) {}
virtual ~ReadDelegate() {}
// base::ObjectWatcher::Delegate methods:
virtual void OnObjectSignaled(HANDLE object);
private:
Core* const core_;
};
class WriteDelegate : public base::win::ObjectWatcher::Delegate {
public:
explicit WriteDelegate(Core* core) : core_(core) {}
virtual ~WriteDelegate() {}
// base::ObjectWatcher::Delegate methods:
virtual void OnObjectSignaled(HANDLE object);
private:
Core* const core_;
};
~Core();
// The socket that created this object.
TCPSocketWin* socket_;
// |reader_| handles the signals from |read_watcher_|.
ReadDelegate reader_;
// |writer_| handles the signals from |write_watcher_|.
WriteDelegate writer_;
// |read_watcher_| watches for events from Connect() and Read().
base::win::ObjectWatcher read_watcher_;
// |write_watcher_| watches for events from Write();
base::win::ObjectWatcher write_watcher_;
DISALLOW_COPY_AND_ASSIGN(Core);
};
TCPSocketWin::Core::Core(TCPSocketWin* socket)
: read_buffer_length_(0),
write_buffer_length_(0),
non_blocking_reads_initialized_(false),
socket_(socket),
reader_(this),
writer_(this) {
memset(&read_overlapped_, 0, sizeof(read_overlapped_));
memset(&write_overlapped_, 0, sizeof(write_overlapped_));
read_overlapped_.hEvent = WSACreateEvent();
write_overlapped_.hEvent = WSACreateEvent();
}
TCPSocketWin::Core::~Core() {
// Make sure the message loop is not watching this object anymore.
read_watcher_.StopWatching();
write_watcher_.StopWatching();
WSACloseEvent(read_overlapped_.hEvent);
memset(&read_overlapped_, 0xaf, sizeof(read_overlapped_));
WSACloseEvent(write_overlapped_.hEvent);
memset(&write_overlapped_, 0xaf, sizeof(write_overlapped_));
}
void TCPSocketWin::Core::WatchForRead() {
// We grab an extra reference because there is an IO operation in progress.
// Balanced in ReadDelegate::OnObjectSignaled().
AddRef();
read_watcher_.StartWatching(read_overlapped_.hEvent, &reader_);
}
void TCPSocketWin::Core::WatchForWrite() {
// We grab an extra reference because there is an IO operation in progress.
// Balanced in WriteDelegate::OnObjectSignaled().
AddRef();
write_watcher_.StartWatching(write_overlapped_.hEvent, &writer_);
}
void TCPSocketWin::Core::ReadDelegate::OnObjectSignaled(HANDLE object) {
DCHECK_EQ(object, core_->read_overlapped_.hEvent);
if (core_->socket_) {
if (core_->socket_->waiting_connect_)
core_->socket_->DidCompleteConnect();
else
core_->socket_->DidSignalRead();
}
core_->Release();
}
void TCPSocketWin::Core::WriteDelegate::OnObjectSignaled(
HANDLE object) {
DCHECK_EQ(object, core_->write_overlapped_.hEvent);
if (core_->socket_)
core_->socket_->DidCompleteWrite();
core_->Release();
}
//-----------------------------------------------------------------------------
TCPSocketWin::TCPSocketWin(net::NetLog* net_log,
const net::NetLog::Source& source)
: socket_(INVALID_SOCKET),
accept_event_(WSA_INVALID_EVENT),
accept_socket_(NULL),
accept_address_(NULL),
waiting_connect_(false),
waiting_read_(false),
waiting_write_(false),
connect_os_error_(0),
logging_multiple_connect_attempts_(false),
net_log_(BoundNetLog::Make(net_log, NetLog::SOURCE_SOCKET)) {
net_log_.BeginEvent(NetLog::TYPE_SOCKET_ALIVE,
source.ToEventParametersCallback());
EnsureWinsockInit();
}
TCPSocketWin::~TCPSocketWin() {
Close();
net_log_.EndEvent(NetLog::TYPE_SOCKET_ALIVE);
}
int TCPSocketWin::Open(AddressFamily family) {
DCHECK(CalledOnValidThread());
DCHECK_EQ(socket_, INVALID_SOCKET);
socket_ = CreatePlatformSocket(ConvertAddressFamily(family), SOCK_STREAM,
IPPROTO_TCP);
if (socket_ == INVALID_SOCKET) {
PLOG(ERROR) << "CreatePlatformSocket() returned an error";
return MapSystemError(WSAGetLastError());
}
if (SetNonBlocking(socket_)) {
int result = MapSystemError(WSAGetLastError());
Close();
return result;
}
return OK;
}
int TCPSocketWin::AdoptConnectedSocket(SOCKET socket,
const IPEndPoint& peer_address) {
DCHECK(CalledOnValidThread());
DCHECK_EQ(socket_, INVALID_SOCKET);
DCHECK(!core_);
socket_ = socket;
if (SetNonBlocking(socket_)) {
int result = MapSystemError(WSAGetLastError());
Close();
return result;
}
core_ = new Core(this);
peer_address_.reset(new IPEndPoint(peer_address));
return OK;
}
int TCPSocketWin::Bind(const IPEndPoint& address) {
DCHECK(CalledOnValidThread());
DCHECK_NE(socket_, INVALID_SOCKET);
SockaddrStorage storage;
if (!address.ToSockAddr(storage.addr, &storage.addr_len))
return ERR_ADDRESS_INVALID;
int result = bind(socket_, storage.addr, storage.addr_len);
if (result < 0) {
PLOG(ERROR) << "bind() returned an error";
return MapSystemError(WSAGetLastError());
}
return OK;
}
int TCPSocketWin::Listen(int backlog) {
DCHECK(CalledOnValidThread());
DCHECK_GT(backlog, 0);
DCHECK_NE(socket_, INVALID_SOCKET);
DCHECK_EQ(accept_event_, WSA_INVALID_EVENT);
accept_event_ = WSACreateEvent();
if (accept_event_ == WSA_INVALID_EVENT) {
PLOG(ERROR) << "WSACreateEvent()";
return MapSystemError(WSAGetLastError());
}
int result = listen(socket_, backlog);
if (result < 0) {
PLOG(ERROR) << "listen() returned an error";
return MapSystemError(WSAGetLastError());
}
return OK;
}
int TCPSocketWin::Accept(scoped_ptr<TCPSocketWin>* socket,
IPEndPoint* address,
const CompletionCallback& callback) {
DCHECK(CalledOnValidThread());
DCHECK(socket);
DCHECK(address);
DCHECK(!callback.is_null());
DCHECK(accept_callback_.is_null());
net_log_.BeginEvent(NetLog::TYPE_TCP_ACCEPT);
int result = AcceptInternal(socket, address);
if (result == ERR_IO_PENDING) {
// Start watching.
WSAEventSelect(socket_, accept_event_, FD_ACCEPT);
accept_watcher_.StartWatching(accept_event_, this);
accept_socket_ = socket;
accept_address_ = address;
accept_callback_ = callback;
}
return result;
}
int TCPSocketWin::Connect(const IPEndPoint& address,
const CompletionCallback& callback) {
DCHECK(CalledOnValidThread());
DCHECK_NE(socket_, INVALID_SOCKET);
DCHECK(!waiting_connect_);
// |peer_address_| and |core_| will be non-NULL if Connect() has been called.
// Unless Close() is called to reset the internal state, a second call to
// Connect() is not allowed.
// Please note that we enforce this even if the previous Connect() has
// completed and failed. Although it is allowed to connect the same |socket_|
// again after a connection attempt failed on Windows, it results in
// unspecified behavior according to POSIX. Therefore, we make it behave in
// the same way as TCPSocketLibevent.
DCHECK(!peer_address_ && !core_);
if (!logging_multiple_connect_attempts_)
LogConnectBegin(AddressList(address));
peer_address_.reset(new IPEndPoint(address));
int rv = DoConnect();
if (rv == ERR_IO_PENDING) {
// Synchronous operation not supported.
DCHECK(!callback.is_null());
read_callback_ = callback;
waiting_connect_ = true;
} else {
DoConnectComplete(rv);
}
return rv;
}
bool TCPSocketWin::IsConnected() const {
DCHECK(CalledOnValidThread());
if (socket_ == INVALID_SOCKET || waiting_connect_)
return false;
if (waiting_read_)
return true;
// Check if connection is alive.
char c;
int rv = recv(socket_, &c, 1, MSG_PEEK);
if (rv == 0)
return false;
if (rv == SOCKET_ERROR && WSAGetLastError() != WSAEWOULDBLOCK)
return false;
return true;
}
bool TCPSocketWin::IsConnectedAndIdle() const {
DCHECK(CalledOnValidThread());
if (socket_ == INVALID_SOCKET || waiting_connect_)
return false;
if (waiting_read_)
return true;
// Check if connection is alive and we haven't received any data
// unexpectedly.
char c;
int rv = recv(socket_, &c, 1, MSG_PEEK);
if (rv >= 0)
return false;
if (WSAGetLastError() != WSAEWOULDBLOCK)
return false;
return true;
}
int TCPSocketWin::Read(IOBuffer* buf,
int buf_len,
const CompletionCallback& callback) {
DCHECK(CalledOnValidThread());
DCHECK_NE(socket_, INVALID_SOCKET);
DCHECK(!waiting_read_);
DCHECK(read_callback_.is_null());
DCHECK(!core_->read_iobuffer_);
return DoRead(buf, buf_len, callback);
}
int TCPSocketWin::Write(IOBuffer* buf,
int buf_len,
const CompletionCallback& callback) {
DCHECK(CalledOnValidThread());
DCHECK_NE(socket_, INVALID_SOCKET);
DCHECK(!waiting_write_);
DCHECK(write_callback_.is_null());
DCHECK_GT(buf_len, 0);
DCHECK(!core_->write_iobuffer_);
base::StatsCounter writes("tcp.writes");
writes.Increment();
WSABUF write_buffer;
write_buffer.len = buf_len;
write_buffer.buf = buf->data();
// TODO(wtc): Remove the assertion after enough testing.
AssertEventNotSignaled(core_->write_overlapped_.hEvent);
DWORD num;
int rv = WSASend(socket_, &write_buffer, 1, &num, 0,
&core_->write_overlapped_, NULL);
if (rv == 0) {
if (ResetEventIfSignaled(core_->write_overlapped_.hEvent)) {
rv = static_cast<int>(num);
if (rv > buf_len || rv < 0) {
// It seems that some winsock interceptors report that more was written
// than was available. Treat this as an error. http://crbug.com/27870
LOG(ERROR) << "Detected broken LSP: Asked to write " << buf_len
<< " bytes, but " << rv << " bytes reported.";
return ERR_WINSOCK_UNEXPECTED_WRITTEN_BYTES;
}
base::StatsCounter write_bytes("tcp.write_bytes");
write_bytes.Add(rv);
net_log_.AddByteTransferEvent(NetLog::TYPE_SOCKET_BYTES_SENT, rv,
buf->data());
return rv;
}
} else {
int os_error = WSAGetLastError();
if (os_error != WSA_IO_PENDING) {
int net_error = MapSystemError(os_error);
net_log_.AddEvent(NetLog::TYPE_SOCKET_WRITE_ERROR,
CreateNetLogSocketErrorCallback(net_error, os_error));
return net_error;
}
}
waiting_write_ = true;
write_callback_ = callback;
core_->write_iobuffer_ = buf;
core_->write_buffer_length_ = buf_len;
core_->WatchForWrite();
return ERR_IO_PENDING;
}
int TCPSocketWin::GetLocalAddress(IPEndPoint* address) const {
DCHECK(CalledOnValidThread());
DCHECK(address);
SockaddrStorage storage;
if (getsockname(socket_, storage.addr, &storage.addr_len))
return MapSystemError(WSAGetLastError());
if (!address->FromSockAddr(storage.addr, storage.addr_len))
return ERR_ADDRESS_INVALID;
return OK;
}
int TCPSocketWin::GetPeerAddress(IPEndPoint* address) const {
DCHECK(CalledOnValidThread());
DCHECK(address);
if (!IsConnected())
return ERR_SOCKET_NOT_CONNECTED;
*address = *peer_address_;
return OK;
}
int TCPSocketWin::SetDefaultOptionsForServer() {
return SetExclusiveAddrUse();
}
void TCPSocketWin::SetDefaultOptionsForClient() {
// Increase the socket buffer sizes from the default sizes for WinXP. In
// performance testing, there is substantial benefit by increasing from 8KB
// to 64KB.
// See also:
// http://support.microsoft.com/kb/823764/EN-US
// On Vista, if we manually set these sizes, Vista turns off its receive
// window auto-tuning feature.
// http://blogs.msdn.com/wndp/archive/2006/05/05/Winhec-blog-tcpip-2.aspx
// Since Vista's auto-tune is better than any static value we can could set,
// only change these on pre-vista machines.
if (base::win::GetVersion() < base::win::VERSION_VISTA) {
const int32 kSocketBufferSize = 64 * 1024;
SetSocketReceiveBufferSize(socket_, kSocketBufferSize);
SetSocketSendBufferSize(socket_, kSocketBufferSize);
}
DisableNagle(socket_, true);
SetTCPKeepAlive(socket_, true, kTCPKeepAliveSeconds);
}
int TCPSocketWin::SetExclusiveAddrUse() {
// On Windows, a bound end point can be hijacked by another process by
// setting SO_REUSEADDR. Therefore a Windows-only option SO_EXCLUSIVEADDRUSE
// was introduced in Windows NT 4.0 SP4. If the socket that is bound to the
// end point has SO_EXCLUSIVEADDRUSE enabled, it is not possible for another
// socket to forcibly bind to the end point until the end point is unbound.
// It is recommend that all server applications must use SO_EXCLUSIVEADDRUSE.
// MSDN: http://goo.gl/M6fjQ.
//
// Unlike on *nix, on Windows a TCP server socket can always bind to an end
// point in TIME_WAIT state without setting SO_REUSEADDR, therefore it is not
// needed here.
//
// SO_EXCLUSIVEADDRUSE will prevent a TCP client socket from binding to an end
// point in TIME_WAIT status. It does not have this effect for a TCP server
// socket.
BOOL true_value = 1;
int rv = setsockopt(socket_, SOL_SOCKET, SO_EXCLUSIVEADDRUSE,
reinterpret_cast<const char*>(&true_value),
sizeof(true_value));
if (rv < 0)
return MapSystemError(errno);
return OK;
}
bool TCPSocketWin::SetReceiveBufferSize(int32 size) {
DCHECK(CalledOnValidThread());
return SetSocketReceiveBufferSize(socket_, size);
}
bool TCPSocketWin::SetSendBufferSize(int32 size) {
DCHECK(CalledOnValidThread());
return SetSocketSendBufferSize(socket_, size);
}
bool TCPSocketWin::SetKeepAlive(bool enable, int delay) {
return SetTCPKeepAlive(socket_, enable, delay);
}
bool TCPSocketWin::SetNoDelay(bool no_delay) {
return DisableNagle(socket_, no_delay);
}
void TCPSocketWin::Close() {
DCHECK(CalledOnValidThread());
if (socket_ != INVALID_SOCKET) {
// Note: don't use CancelIo to cancel pending IO because it doesn't work
// when there is a Winsock layered service provider.
// In most socket implementations, closing a socket results in a graceful
// connection shutdown, but in Winsock we have to call shutdown explicitly.
// See the MSDN page "Graceful Shutdown, Linger Options, and Socket Closure"
// at http://msdn.microsoft.com/en-us/library/ms738547.aspx
shutdown(socket_, SD_SEND);
// This cancels any pending IO.
if (closesocket(socket_) < 0)
PLOG(ERROR) << "closesocket";
socket_ = INVALID_SOCKET;
}
if (!accept_callback_.is_null()) {
accept_watcher_.StopWatching();
accept_socket_ = NULL;
accept_address_ = NULL;
accept_callback_.Reset();
}
if (accept_event_) {
WSACloseEvent(accept_event_);
accept_event_ = WSA_INVALID_EVENT;
}
if (core_) {
if (waiting_connect_) {
// We closed the socket, so this notification will never come.
// From MSDN' WSAEventSelect documentation:
// "Closing a socket with closesocket also cancels the association and
// selection of network events specified in WSAEventSelect for the
// socket".
core_->Release();
}
core_->Detach();
core_ = NULL;
}
waiting_connect_ = false;
waiting_read_ = false;
waiting_write_ = false;
read_callback_.Reset();
write_callback_.Reset();
peer_address_.reset();
connect_os_error_ = 0;
}
bool TCPSocketWin::UsingTCPFastOpen() const {
// Not supported on windows.
return false;
}
void TCPSocketWin::StartLoggingMultipleConnectAttempts(
const AddressList& addresses) {
if (!logging_multiple_connect_attempts_) {
logging_multiple_connect_attempts_ = true;
LogConnectBegin(addresses);
} else {
NOTREACHED();
}
}
void TCPSocketWin::EndLoggingMultipleConnectAttempts(int net_error) {
if (logging_multiple_connect_attempts_) {
LogConnectEnd(net_error);
logging_multiple_connect_attempts_ = false;
} else {
NOTREACHED();
}
}
int TCPSocketWin::AcceptInternal(scoped_ptr<TCPSocketWin>* socket,
IPEndPoint* address) {
SockaddrStorage storage;
int new_socket = accept(socket_, storage.addr, &storage.addr_len);
if (new_socket < 0) {
int net_error = MapSystemError(WSAGetLastError());
if (net_error != ERR_IO_PENDING)
net_log_.EndEventWithNetErrorCode(NetLog::TYPE_TCP_ACCEPT, net_error);
return net_error;
}
IPEndPoint ip_end_point;
if (!ip_end_point.FromSockAddr(storage.addr, storage.addr_len)) {
NOTREACHED();
if (closesocket(new_socket) < 0)
PLOG(ERROR) << "closesocket";
net_log_.EndEventWithNetErrorCode(NetLog::TYPE_TCP_ACCEPT, ERR_FAILED);
return ERR_FAILED;
}
scoped_ptr<TCPSocketWin> tcp_socket(new TCPSocketWin(
net_log_.net_log(), net_log_.source()));
int adopt_result = tcp_socket->AdoptConnectedSocket(new_socket, ip_end_point);
if (adopt_result != OK) {
net_log_.EndEventWithNetErrorCode(NetLog::TYPE_TCP_ACCEPT, adopt_result);
return adopt_result;
}
*socket = tcp_socket.Pass();
*address = ip_end_point;
net_log_.EndEvent(NetLog::TYPE_TCP_ACCEPT,
CreateNetLogIPEndPointCallback(&ip_end_point));
return OK;
}
void TCPSocketWin::OnObjectSignaled(HANDLE object) {
WSANETWORKEVENTS ev;
if (WSAEnumNetworkEvents(socket_, accept_event_, &ev) == SOCKET_ERROR) {
PLOG(ERROR) << "WSAEnumNetworkEvents()";
return;
}
if (ev.lNetworkEvents & FD_ACCEPT) {
int result = AcceptInternal(accept_socket_, accept_address_);
if (result != ERR_IO_PENDING) {
accept_socket_ = NULL;
accept_address_ = NULL;
base::ResetAndReturn(&accept_callback_).Run(result);
}
} else {
// This happens when a client opens a connection and closes it before we
// have a chance to accept it.
DCHECK(ev.lNetworkEvents == 0);
// Start watching the next FD_ACCEPT event.
WSAEventSelect(socket_, accept_event_, FD_ACCEPT);
accept_watcher_.StartWatching(accept_event_, this);
}
}
int TCPSocketWin::DoConnect() {
DCHECK_EQ(connect_os_error_, 0);
DCHECK(!core_);
net_log_.BeginEvent(NetLog::TYPE_TCP_CONNECT_ATTEMPT,
CreateNetLogIPEndPointCallback(peer_address_.get()));
core_ = new Core(this);
// WSAEventSelect sets the socket to non-blocking mode as a side effect.
// Our connect() and recv() calls require that the socket be non-blocking.
WSAEventSelect(socket_, core_->read_overlapped_.hEvent, FD_CONNECT);
SockaddrStorage storage;
if (!peer_address_->ToSockAddr(storage.addr, &storage.addr_len))
return ERR_INVALID_ARGUMENT;
if (!connect(socket_, storage.addr, storage.addr_len)) {
// Connected without waiting!
//
// The MSDN page for connect says:
// With a nonblocking socket, the connection attempt cannot be completed
// immediately. In this case, connect will return SOCKET_ERROR, and
// WSAGetLastError will return WSAEWOULDBLOCK.
// which implies that for a nonblocking socket, connect never returns 0.
// It's not documented whether the event object will be signaled or not
// if connect does return 0. So the code below is essentially dead code
// and we don't know if it's correct.
NOTREACHED();
if (ResetEventIfSignaled(core_->read_overlapped_.hEvent))
return OK;
} else {
int os_error = WSAGetLastError();
if (os_error != WSAEWOULDBLOCK) {
LOG(ERROR) << "connect failed: " << os_error;
connect_os_error_ = os_error;
int rv = MapConnectError(os_error);
CHECK_NE(ERR_IO_PENDING, rv);
return rv;
}
}
core_->WatchForRead();
return ERR_IO_PENDING;
}
void TCPSocketWin::DoConnectComplete(int result) {
// Log the end of this attempt (and any OS error it threw).
int os_error = connect_os_error_;
connect_os_error_ = 0;
if (result != OK) {
net_log_.EndEvent(NetLog::TYPE_TCP_CONNECT_ATTEMPT,
NetLog::IntegerCallback("os_error", os_error));
} else {
net_log_.EndEvent(NetLog::TYPE_TCP_CONNECT_ATTEMPT);
}
if (!logging_multiple_connect_attempts_)
LogConnectEnd(result);
}
void TCPSocketWin::LogConnectBegin(const AddressList& addresses) {
base::StatsCounter connects("tcp.connect");
connects.Increment();
net_log_.BeginEvent(NetLog::TYPE_TCP_CONNECT,
addresses.CreateNetLogCallback());
}
void TCPSocketWin::LogConnectEnd(int net_error) {
if (net_error == OK)
UpdateConnectionTypeHistograms(CONNECTION_ANY);
if (net_error != OK) {
net_log_.EndEventWithNetErrorCode(NetLog::TYPE_TCP_CONNECT, net_error);
return;
}
struct sockaddr_storage source_address;
socklen_t addrlen = sizeof(source_address);
int rv = getsockname(
socket_, reinterpret_cast<struct sockaddr*>(&source_address), &addrlen);
if (rv != 0) {
LOG(ERROR) << "getsockname() [rv: " << rv
<< "] error: " << WSAGetLastError();
NOTREACHED();
net_log_.EndEventWithNetErrorCode(NetLog::TYPE_TCP_CONNECT, rv);
return;
}
net_log_.EndEvent(
NetLog::TYPE_TCP_CONNECT,
CreateNetLogSourceAddressCallback(
reinterpret_cast<const struct sockaddr*>(&source_address),
sizeof(source_address)));
}
int TCPSocketWin::DoRead(IOBuffer* buf, int buf_len,
const CompletionCallback& callback) {
if (!core_->non_blocking_reads_initialized_) {
WSAEventSelect(socket_, core_->read_overlapped_.hEvent,
FD_READ | FD_CLOSE);
core_->non_blocking_reads_initialized_ = true;
}
int rv = recv(socket_, buf->data(), buf_len, 0);
if (rv == SOCKET_ERROR) {
int os_error = WSAGetLastError();
if (os_error != WSAEWOULDBLOCK) {
int net_error = MapSystemError(os_error);
net_log_.AddEvent(
NetLog::TYPE_SOCKET_READ_ERROR,
CreateNetLogSocketErrorCallback(net_error, os_error));
return net_error;
}
} else {
base::StatsCounter read_bytes("tcp.read_bytes");
if (rv > 0)
read_bytes.Add(rv);
net_log_.AddByteTransferEvent(NetLog::TYPE_SOCKET_BYTES_RECEIVED, rv,
buf->data());
return rv;
}
waiting_read_ = true;
read_callback_ = callback;
core_->read_iobuffer_ = buf;
core_->read_buffer_length_ = buf_len;
core_->WatchForRead();
return ERR_IO_PENDING;
}
void TCPSocketWin::DidCompleteConnect() {
DCHECK(waiting_connect_);
DCHECK(!read_callback_.is_null());
int result;
WSANETWORKEVENTS events;
int rv = WSAEnumNetworkEvents(socket_, core_->read_overlapped_.hEvent,
&events);
int os_error = 0;
if (rv == SOCKET_ERROR) {
NOTREACHED();
os_error = WSAGetLastError();
result = MapSystemError(os_error);
} else if (events.lNetworkEvents & FD_CONNECT) {
os_error = events.iErrorCode[FD_CONNECT_BIT];
result = MapConnectError(os_error);
} else {
NOTREACHED();
result = ERR_UNEXPECTED;
}
connect_os_error_ = os_error;
DoConnectComplete(result);
waiting_connect_ = false;
DCHECK_NE(result, ERR_IO_PENDING);
base::ResetAndReturn(&read_callback_).Run(result);
}
void TCPSocketWin::DidCompleteWrite() {
DCHECK(waiting_write_);
DCHECK(!write_callback_.is_null());
DWORD num_bytes, flags;
BOOL ok = WSAGetOverlappedResult(socket_, &core_->write_overlapped_,
&num_bytes, FALSE, &flags);
WSAResetEvent(core_->write_overlapped_.hEvent);
waiting_write_ = false;
int rv;
if (!ok) {
int os_error = WSAGetLastError();
rv = MapSystemError(os_error);
net_log_.AddEvent(NetLog::TYPE_SOCKET_WRITE_ERROR,
CreateNetLogSocketErrorCallback(rv, os_error));
} else {
rv = static_cast<int>(num_bytes);
if (rv > core_->write_buffer_length_ || rv < 0) {
// It seems that some winsock interceptors report that more was written
// than was available. Treat this as an error. http://crbug.com/27870
LOG(ERROR) << "Detected broken LSP: Asked to write "
<< core_->write_buffer_length_ << " bytes, but " << rv
<< " bytes reported.";
rv = ERR_WINSOCK_UNEXPECTED_WRITTEN_BYTES;
} else {
base::StatsCounter write_bytes("tcp.write_bytes");
write_bytes.Add(num_bytes);
net_log_.AddByteTransferEvent(NetLog::TYPE_SOCKET_BYTES_SENT, num_bytes,
core_->write_iobuffer_->data());
}
}
core_->write_iobuffer_ = NULL;
DCHECK_NE(rv, ERR_IO_PENDING);
base::ResetAndReturn(&write_callback_).Run(rv);
}
void TCPSocketWin::DidSignalRead() {
DCHECK(waiting_read_);
DCHECK(!read_callback_.is_null());
int os_error = 0;
WSANETWORKEVENTS network_events;
int rv = WSAEnumNetworkEvents(socket_, core_->read_overlapped_.hEvent,
&network_events);
if (rv == SOCKET_ERROR) {
os_error = WSAGetLastError();
rv = MapSystemError(os_error);
} else if (network_events.lNetworkEvents) {
DCHECK_EQ(network_events.lNetworkEvents & ~(FD_READ | FD_CLOSE), 0);
// If network_events.lNetworkEvents is FD_CLOSE and
// network_events.iErrorCode[FD_CLOSE_BIT] is 0, it is a graceful
// connection closure. It is tempting to directly set rv to 0 in
// this case, but the MSDN pages for WSAEventSelect and
// WSAAsyncSelect recommend we still call DoRead():
// FD_CLOSE should only be posted after all data is read from a
// socket, but an application should check for remaining data upon
// receipt of FD_CLOSE to avoid any possibility of losing data.
//
// If network_events.iErrorCode[FD_READ_BIT] or
// network_events.iErrorCode[FD_CLOSE_BIT] is nonzero, still call
// DoRead() because recv() reports a more accurate error code
// (WSAECONNRESET vs. WSAECONNABORTED) when the connection was
// reset.
rv = DoRead(core_->read_iobuffer_, core_->read_buffer_length_,
read_callback_);
if (rv == ERR_IO_PENDING)
return;
} else {
// This may happen because Read() may succeed synchronously and
// consume all the received data without resetting the event object.
core_->WatchForRead();
return;
}
waiting_read_ = false;
core_->read_iobuffer_ = NULL;
core_->read_buffer_length_ = 0;
DCHECK_NE(rv, ERR_IO_PENDING);
base::ResetAndReturn(&read_callback_).Run(rv);
}
} // namespace net