open_toontown_panda3d/panda/src/net/connection.cxx

553 lines
18 KiB
C++

// Filename: connection.cxx
// Created by: jns (07Feb00)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) Carnegie Mellon University. All rights reserved.
//
// All use of this software is subject to the terms of the revised BSD
// license. You should have received a copy of this license along
// with this source code in a file named "LICENSE."
//
////////////////////////////////////////////////////////////////////
#include "connection.h"
#include "connectionManager.h"
#include "netDatagram.h"
#include "datagramTCPHeader.h"
#include "datagramUDPHeader.h"
#include "config_net.h"
#include "config_express.h" // for collect_tcp
#include "trueClock.h"
#include "pnotify.h"
#include "lightReMutexHolder.h"
#include "socket_ip.h"
#include "socket_tcp.h"
#include "socket_udp.h"
#include "dcast.h"
////////////////////////////////////////////////////////////////////
// Function: Connection::Constructor
// Access: Published
// Description: Creates a connection. Normally this constructor
// should not be used directly by user code; use one of
// the methods in ConnectionManager to make a new
// connection.
////////////////////////////////////////////////////////////////////
Connection::
Connection(ConnectionManager *manager, Socket_IP *socket) :
_manager(manager),
_socket(socket)
{
_collect_tcp = collect_tcp;
_collect_tcp_interval = collect_tcp_interval;
_queued_data_start = 0.0;
_queued_count = 0;
#if defined(HAVE_THREADS) && defined(SIMPLE_THREADS)
// In the presence of SIMPLE_THREADS, we use non-blocking I/O. We
// simulate blocking by yielding the thread.
if (_socket->SetNonBlocking() != ALL_OK) {
net_cat.warning()
<< "Unable to set non-blocking status on socket\n";
}
#endif
}
////////////////////////////////////////////////////////////////////
// Function: Connection::Destructor
// Access: Published
// Description: Closes a connection.
////////////////////////////////////////////////////////////////////
Connection::
~Connection() {
net_cat.info()
<< "Deleting connection " << (void *)this << "\n";
if (_socket != (Socket_IP *)NULL) {
flush();
_socket->Close();
delete _socket;
}
}
////////////////////////////////////////////////////////////////////
// Function: Connection::get_address
// Access: Published
// Description: Returns the address bound to this connection, if it
// is a TCP connection.
////////////////////////////////////////////////////////////////////
NetAddress Connection::
get_address() const {
Socket_Address addr = _socket->GetPeerName();
return NetAddress(addr);
}
////////////////////////////////////////////////////////////////////
// Function: Connection::get_manager
// Access: Published
// Description: Returns a pointer to the ConnectionManager object
// that serves this connection.
////////////////////////////////////////////////////////////////////
ConnectionManager *Connection::
get_manager() const {
return _manager;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::get_socket
// Access: Published
// Description: Returns the internal Socket_IP that defines the
// connection.
////////////////////////////////////////////////////////////////////
Socket_IP *Connection::
get_socket() const {
return _socket;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_collect_tcp
// Access: Published
// Description: Enables or disables "collect-tcp" mode. In this
// mode, individual TCP packets are not sent
// immediately, but rather they are collected together
// and accumulated to be sent periodically as one larger
// TCP packet. This cuts down on overhead from the
// TCP/IP protocol, especially if many small packets
// need to be sent on the same connection, but it
// introduces additional latency (since packets must be
// held before they can be sent).
//
// See set_collect_tcp_interval() to specify the
// interval of time for which to hold packets before
// sending them.
//
// If you enable this mode, you may also need to
// periodically call consider_flush() to flush the queue
// if no packets have been sent recently.
////////////////////////////////////////////////////////////////////
void Connection::
set_collect_tcp(bool collect_tcp) {
_collect_tcp = collect_tcp;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::get_collect_tcp
// Access: Published
// Description: Returns the current setting of "collect-tcp" mode.
// See set_collect_tcp().
////////////////////////////////////////////////////////////////////
bool Connection::
get_collect_tcp() const {
return _collect_tcp;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_collect_tcp_interval
// Access: Published
// Description: Specifies the interval in time, in seconds, for which
// to hold TCP packets before sending all of the
// recently received packets at once. This only has
// meaning if "collect-tcp" mode is enabled; see
// set_collect_tcp().
////////////////////////////////////////////////////////////////////
void Connection::
set_collect_tcp_interval(double interval) {
_collect_tcp_interval = interval;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::get_collect_tcp_interval
// Access: Published
// Description: Returns the interval in time, in seconds, for which
// to hold TCP packets before sending all of the
// recently received packets at once. This only has
// meaning if "collect-tcp" mode is enabled; see
// set_collect_tcp().
////////////////////////////////////////////////////////////////////
double Connection::
get_collect_tcp_interval() const {
return _collect_tcp_interval;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::consider_flush
// Access: Published
// Description: Sends the most recently queued TCP datagram(s) if
// enough time has elapsed. This only has meaning if
// set_collect_tcp() has been set to true.
////////////////////////////////////////////////////////////////////
bool Connection::
consider_flush() {
LightReMutexHolder holder(_write_mutex);
if (!_collect_tcp) {
return do_flush();
} else {
double elapsed =
TrueClock::get_global_ptr()->get_short_time() - _queued_data_start;
// If the elapsed time is negative, someone must have reset the
// clock back, so just go ahead and flush.
if (elapsed < 0.0 || elapsed >= _collect_tcp_interval) {
return do_flush();
}
}
return true;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::flush
// Access: Published
// Description: Sends the most recently queued TCP datagram(s) now.
// This only has meaning if set_collect_tcp() has been
// set to true.
////////////////////////////////////////////////////////////////////
bool Connection::
flush() {
LightReMutexHolder holder(_write_mutex);
return do_flush();
}
/*
This method is disabled. We don't provide enough interface to use
non-blocking I/O effectively at this level, so we shouldn't provide
this call. Specifically, we don't provide a way to query whether an
operation failed because it would have blocked or not.
////////////////////////////////////////////////////////////////////
// Function: Connection::set_nonblock
// Access: Published
// Description: Sets whether nonblocking I/O should be in effect.
////////////////////////////////////////////////////////////////////
void Connection::
set_nonblock(bool flag) {
if (flag) {
_socket->SetNonBlocking();
} else {
_socket->SetBlocking();
}
}
*/
////////////////////////////////////////////////////////////////////
// Function: Connection::set_linger
// Access: Published
// Description: Sets the time to linger on close if data is present.
// If flag is false, when you close a socket with data
// available the system attempts to deliver the data to
// the peer (the default behavior). If flag is false
// but time is zero, the system discards any undelivered
// data when you close the socket. If flag is false but
// time is nonzero, the system waits up to time seconds
// to deliver the data.
////////////////////////////////////////////////////////////////////
void Connection::
set_linger(bool flag, double time) {
Socket_TCP *tcp;
DCAST_INTO_V(tcp, _socket);
if (flag) {
tcp->SetLinger((int)time);
} else {
tcp->DontLinger();
}
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_reuse_addr
// Access: Published
// Description: Sets whether local address reuse is allowed.
////////////////////////////////////////////////////////////////////
void Connection::
set_reuse_addr(bool flag) {
_socket->SetReuseAddress(flag);
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_keep_alive
// Access: Published
// Description: Sets whether the connection is periodically tested to
// see if it is still alive.
////////////////////////////////////////////////////////////////////
void Connection::
set_keep_alive(bool flag) {
// TODO.
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_recv_buffer_size
// Access: Published
// Description: Sets the size of the receive buffer, in bytes.
////////////////////////////////////////////////////////////////////
void Connection::
set_recv_buffer_size(int size) {
_socket->SetRecvBufferSize(size);
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_send_buffer_size
// Access: Published
// Description: Sets the size of the send buffer, in bytes.
////////////////////////////////////////////////////////////////////
void Connection::
set_send_buffer_size(int size) {
Socket_TCP *tcp;
DCAST_INTO_V(tcp, _socket);
tcp->SetSendBufferSize(size);
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_ip_time_to_live
// Access: Published
// Description: Sets IP time-to-live.
////////////////////////////////////////////////////////////////////
void Connection::
set_ip_time_to_live(int ttl) {
// TODO.
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_ip_type_of_service
// Access: Published
// Description: Sets IP type-of-service and precedence.
////////////////////////////////////////////////////////////////////
void Connection::
set_ip_type_of_service(int tos) {
// TODO.
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_no_delay
// Access: Published
// Description: If flag is true, this disables the Nagle algorithm,
// and prevents delaying of send to coalesce packets.
////////////////////////////////////////////////////////////////////
void Connection::
set_no_delay(bool flag) {
Socket_TCP *tcp;
DCAST_INTO_V(tcp, _socket);
tcp->SetNoDelay(flag);
}
////////////////////////////////////////////////////////////////////
// Function: Connection::set_max_segment
// Access: Published
// Description: Sets the maximum segment size.
////////////////////////////////////////////////////////////////////
void Connection::
set_max_segment(int size) {
// TODO.
}
////////////////////////////////////////////////////////////////////
// Function: Connection::send_datagram
// Access: Private
// Description: This method is intended only to be called by
// ConnectionWriter. It atomically writes the given
// datagram to the socket, returning true on success,
// false on failure. If the socket seems to be closed,
// it notifies the ConnectionManager.
////////////////////////////////////////////////////////////////////
bool Connection::
send_datagram(const NetDatagram &datagram, int tcp_header_size) {
nassertr(_socket != (Socket_IP *)NULL, false);
if (_socket->is_exact_type(Socket_UDP::get_class_type())) {
// We have to send UDP right away.
Socket_UDP *udp;
DCAST_INTO_R(udp, _socket, false);
LightReMutexHolder holder(_write_mutex);
DatagramUDPHeader header(datagram);
string data;
data += header.get_header();
data += datagram.get_message();
if (net_cat.is_debug()) {
header.verify_datagram(datagram);
}
int bytes_to_send = data.length();
Socket_Address addr = datagram.get_address().get_addr();
bool okflag = udp->SendTo(data, addr);
#if defined(HAVE_THREADS) && defined(SIMPLE_THREADS)
while (!okflag && udp->GetLastError() == LOCAL_BLOCKING_ERROR) {
Thread::force_yield();
okflag = udp->SendTo(data, addr);
}
#endif // SIMPLE_THREADS
if (net_cat.is_spam()) {
net_cat.spam()
<< "Sent UDP datagram with "
<< bytes_to_send << " bytes to " << (void *)this
<< ", ok = " << okflag << "\n";
}
return check_send_error(okflag);
}
// We might queue up TCP packets for later sending.
if (tcp_header_size == 2 && datagram.get_length() >= 0x10000) {
net_cat.error()
<< "Attempt to send TCP datagram of " << datagram.get_length()
<< " bytes--too long!\n";
nassert_raise("Datagram too long");
return false;
}
DatagramTCPHeader header(datagram, tcp_header_size);
LightReMutexHolder holder(_write_mutex);
_queued_data += header.get_header();
_queued_data += datagram.get_message();
_queued_count++;
if (net_cat.is_debug()) {
header.verify_datagram(datagram, tcp_header_size);
}
if (!_collect_tcp ||
TrueClock::get_global_ptr()->get_short_time() - _queued_data_start >= _collect_tcp_interval) {
return do_flush();
}
return true;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::send_raw_datagram
// Access: Private
// Description: This method is intended only to be called by
// ConnectionWriter. It atomically writes the given
// datagram to the socket, without the Datagram header.
////////////////////////////////////////////////////////////////////
bool Connection::
send_raw_datagram(const NetDatagram &datagram) {
nassertr(_socket != (Socket_IP *)NULL, false);
if (_socket->is_exact_type(Socket_UDP::get_class_type())) {
// We have to send UDP right away.
Socket_UDP *udp;
DCAST_INTO_R(udp, _socket, false);
string data = datagram.get_message();
LightReMutexHolder holder(_write_mutex);
Socket_Address addr = datagram.get_address().get_addr();
bool okflag = udp->SendTo(data, addr);
#if defined(HAVE_THREADS) && defined(SIMPLE_THREADS)
while (!okflag && udp->GetLastError() == LOCAL_BLOCKING_ERROR) {
Thread::force_yield();
okflag = udp->SendTo(data, addr);
}
#endif // SIMPLE_THREADS
if (net_cat.is_spam()) {
net_cat.spam()
<< "Sent UDP datagram with "
<< data.size() << " bytes to " << (void *)this
<< ", ok = " << okflag << "\n";
}
return check_send_error(okflag);
}
// We might queue up TCP packets for later sending.
LightReMutexHolder holder(_write_mutex);
_queued_data += datagram.get_message();
_queued_count++;
if (!_collect_tcp ||
TrueClock::get_global_ptr()->get_short_time() - _queued_data_start >= _collect_tcp_interval) {
return do_flush();
}
return true;
}
////////////////////////////////////////////////////////////////////
// Function: Connection::do_flush
// Access: Private
// Description: The private implementation of flush(), this assumes
// the _write_mutex is already held.
////////////////////////////////////////////////////////////////////
bool Connection::
do_flush() {
if (_queued_data.empty()) {
_queued_count = 0;
_queued_data_start = TrueClock::get_global_ptr()->get_short_time();
return true;
}
if (net_cat.is_spam()) {
net_cat.spam()
<< "Sending " << _queued_count << " TCP datagram(s) with "
<< _queued_data.length() << " total bytes to " << (void *)this << "\n";
}
Socket_TCP *tcp;
DCAST_INTO_R(tcp, _socket, false);
string sending_data;
_queued_data.swap(sending_data);
_queued_count = 0;
_queued_data_start = TrueClock::get_global_ptr()->get_short_time();
int data_sent = tcp->SendData(sending_data);
bool okflag = (data_sent == (int)sending_data.size());
#if defined(HAVE_THREADS) && defined(SIMPLE_THREADS)
if (!okflag) {
int total_sent = 0;
if (data_sent > 0) {
total_sent += data_sent;
}
while (!okflag && (data_sent > 0 || tcp->GetLastError() == LOCAL_BLOCKING_ERROR)) {
Thread::force_yield();
data_sent = tcp->SendData(sending_data.data() + total_sent, sending_data.size() - total_sent);
if (data_sent > 0) {
total_sent += data_sent;
}
okflag = (total_sent == (int)sending_data.size());
}
}
#endif // SIMPLE_THREADS
return check_send_error(okflag);
}
////////////////////////////////////////////////////////////////////
// Function: Connection::check_send_error
// Access: Private
// Description: Checks the return value of a Send() or SendTo()
// call.
////////////////////////////////////////////////////////////////////
bool Connection::
check_send_error(bool okflag) {
if (!okflag) {
static ConfigVariableBool abort_send_error("abort-send-error", false);
if (abort_send_error) {
nassertr(false, false);
}
// Assume any error means the connection has been reset; tell
// our manager about it and ignore it.
if (_manager != (ConnectionManager *)NULL) {
_manager->flush_read_connection(this);
_manager->connection_reset(this, okflag);
}
return false;
}
return true;
}