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/* $Id$ */
/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file tcp.cpp Basic functions to receive and send TCP packets.
*/
#ifdef ENABLE_NETWORK
#include "../../stdafx.h"
#include "../../debug.h"
#include "tcp.h"
NetworkTCPSocketHandler::NetworkTCPSocketHandler(SOCKET s) :
NetworkSocketHandler(),
packet_queue(NULL), packet_recv(NULL),
sock(s), writable(false)
{
}
NetworkTCPSocketHandler::~NetworkTCPSocketHandler()
{
this->CloseConnection();
if (this->sock != INVALID_SOCKET) closesocket(this->sock);
this->sock = INVALID_SOCKET;
}
NetworkRecvStatus NetworkTCPSocketHandler::CloseConnection(bool error)
{
this->writable = false;
NetworkSocketHandler::CloseConnection(error);
/* Free all pending and partially received packets */
while (this->packet_queue != NULL) {
Packet *p = this->packet_queue->next;
delete this->packet_queue;
this->packet_queue = p;
}
delete this->packet_recv;
this->packet_recv = NULL;
return NETWORK_RECV_STATUS_OKAY;
}
/**
* This function puts the packet in the send-queue and it is send as
* soon as possible. This is the next tick, or maybe one tick later
* if the OS-network-buffer is full)
* @param packet the packet to send
*/
void NetworkTCPSocketHandler::Send_Packet(Packet *packet)
{
Packet *p;
assert(packet != NULL);
packet->PrepareToSend();
/* Locate last packet buffered for the client */
p = this->packet_queue;
if (p == NULL) {
/* No packets yet */
this->packet_queue = packet;
} else {
/* Skip to the last packet */
while (p->next != NULL) p = p->next;
p->next = packet;
}
}
/**
* Sends all the buffered packets out for this client. It stops when:
* 1) all packets are send (queue is empty)
* 2) the OS reports back that it can not send any more
* data right now (full network-buffer, it happens ;))
* 3) sending took too long
* @param closing_down Whether we are closing down the connection.
*/
bool NetworkTCPSocketHandler::Send_Packets(bool closing_down)
{
ssize_t res;
Packet *p;
/* We can not write to this socket!! */
if (!this->writable) return false;
if (!this->IsConnected()) return false;
p = this->packet_queue;
while (p != NULL) {
res = send(this->sock, (const char*)p->buffer + p->pos, p->size - p->pos, 0);
if (res == -1) {
int err = GET_LAST_ERROR();
if (err != EWOULDBLOCK) {
/* Something went wrong.. close client! */
if (!closing_down) {
DEBUG(net, 0, "send failed with error %d", err);
this->CloseConnection();
}
return false;
}
return true;
}
if (res == 0) {
/* Client/server has left us :( */
if (!closing_down) this->CloseConnection();
return false;
}
p->pos += res;
/* Is this packet sent? */
if (p->pos == p->size) {
/* Go to the next packet */
this->packet_queue = p->next;
delete p;
p = this->packet_queue;
} else {
return true;
}
}
return true;
}
/**
* Receives a packet for the given client
* @param status the variable to store the status into
* @return the received packet (or NULL when it didn't receive one)
*/
Packet *NetworkTCPSocketHandler::Recv_Packet()
{
ssize_t res;
if (!this->IsConnected()) return NULL;
if (this->packet_recv == NULL) {
this->packet_recv = new Packet(this);
}
Packet *p = this->packet_recv;
/* Read packet size */
if (p->pos < sizeof(PacketSize)) {
while (p->pos < sizeof(PacketSize)) {
/* Read the size of the packet */
res = recv(this->sock, (char*)p->buffer + p->pos, sizeof(PacketSize) - p->pos, 0);
if (res == -1) {
int err = GET_LAST_ERROR();
if (err != EWOULDBLOCK) {
/* Something went wrong... (104 is connection reset by peer) */
if (err != 104) DEBUG(net, 0, "recv failed with error %d", err);
this->CloseConnection();
return NULL;
}
/* Connection would block, so stop for now */
return NULL;
}
if (res == 0) {
/* Client/server has left */
this->CloseConnection();
return NULL;
}
p->pos += res;
}
/* Read the packet size from the received packet */
p->ReadRawPacketSize();
if (p->size > SEND_MTU) {
this->CloseConnection();
return NULL;
}
}
/* Read rest of packet */
while (p->pos < p->size) {
res = recv(this->sock, (char*)p->buffer + p->pos, p->size - p->pos, 0);
if (res == -1) {
int err = GET_LAST_ERROR();
if (err != EWOULDBLOCK) {
/* Something went wrong... (104 is connection reset by peer) */
if (err != 104) DEBUG(net, 0, "recv failed with error %d", err);
this->CloseConnection();
return NULL;
}
/* Connection would block */
return NULL;
}
if (res == 0) {
/* Client/server has left */
this->CloseConnection();
return NULL;
}
p->pos += res;
}
/* Prepare for receiving a new packet */
this->packet_recv = NULL;
p->PrepareToRead();
return p;
}
bool NetworkTCPSocketHandler::IsPacketQueueEmpty()
{
return this->packet_queue == NULL;
}
#endif /* ENABLE_NETWORK */
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