tcp.cpp

Go to the documentation of this file.
00001 /* $Id: tcp.cpp 17746 2009-10-09 11:03:00Z smatz $ */
00002 
00003 /*
00004  * This file is part of OpenTTD.
00005  * 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.
00006  * 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.
00007  * 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/>.
00008  */
00009 
00014 #ifdef ENABLE_NETWORK
00015 
00016 #include "../../stdafx.h"
00017 #include "../../debug.h"
00018 
00019 #include "tcp.h"
00020 
00021 NetworkTCPSocketHandler::NetworkTCPSocketHandler(SOCKET s) :
00022     NetworkSocketHandler(),
00023     packet_queue(NULL), packet_recv(NULL),
00024     sock(s), writable(false)
00025 {
00026 }
00027 
00028 NetworkTCPSocketHandler::~NetworkTCPSocketHandler()
00029 {
00030   this->CloseConnection();
00031 
00032   if (this->sock != INVALID_SOCKET) closesocket(this->sock);
00033   this->sock = INVALID_SOCKET;
00034 }
00035 
00036 NetworkRecvStatus NetworkTCPSocketHandler::CloseConnection(bool error)
00037 {
00038   this->writable = false;
00039   NetworkSocketHandler::CloseConnection(error);
00040 
00041   /* Free all pending and partially received packets */
00042   while (this->packet_queue != NULL) {
00043     Packet *p = this->packet_queue->next;
00044     delete this->packet_queue;
00045     this->packet_queue = p;
00046   }
00047   delete this->packet_recv;
00048   this->packet_recv = NULL;
00049 
00050   return NETWORK_RECV_STATUS_OKAY;
00051 }
00052 
00059 void NetworkTCPSocketHandler::Send_Packet(Packet *packet)
00060 {
00061   Packet *p;
00062   assert(packet != NULL);
00063 
00064   packet->PrepareToSend();
00065 
00066   /* Locate last packet buffered for the client */
00067   p = this->packet_queue;
00068   if (p == NULL) {
00069     /* No packets yet */
00070     this->packet_queue = packet;
00071   } else {
00072     /* Skip to the last packet */
00073     while (p->next != NULL) p = p->next;
00074     p->next = packet;
00075   }
00076 }
00077 
00085 bool NetworkTCPSocketHandler::Send_Packets()
00086 {
00087   ssize_t res;
00088   Packet *p;
00089 
00090   /* We can not write to this socket!! */
00091   if (!this->writable) return false;
00092   if (!this->IsConnected()) return false;
00093 
00094   p = this->packet_queue;
00095   while (p != NULL) {
00096     res = send(this->sock, (const char*)p->buffer + p->pos, p->size - p->pos, 0);
00097     if (res == -1) {
00098       int err = GET_LAST_ERROR();
00099       if (err != EWOULDBLOCK) {
00100         /* Something went wrong.. close client! */
00101         DEBUG(net, 0, "send failed with error %d", err);
00102         this->CloseConnection();
00103         return false;
00104       }
00105       return true;
00106     }
00107     if (res == 0) {
00108       /* Client/server has left us :( */
00109       this->CloseConnection();
00110       return false;
00111     }
00112 
00113     p->pos += res;
00114 
00115     /* Is this packet sent? */
00116     if (p->pos == p->size) {
00117       /* Go to the next packet */
00118       this->packet_queue = p->next;
00119       delete p;
00120       p = this->packet_queue;
00121     } else {
00122       return true;
00123     }
00124   }
00125 
00126   return true;
00127 }
00128 
00134 Packet *NetworkTCPSocketHandler::Recv_Packet()
00135 {
00136   ssize_t res;
00137 
00138   if (!this->IsConnected()) return NULL;
00139 
00140   if (this->packet_recv == NULL) {
00141     this->packet_recv = new Packet(this);
00142   }
00143 
00144   Packet *p = this->packet_recv;
00145 
00146   /* Read packet size */
00147   if (p->pos < sizeof(PacketSize)) {
00148     while (p->pos < sizeof(PacketSize)) {
00149     /* Read the size of the packet */
00150       res = recv(this->sock, (char*)p->buffer + p->pos, sizeof(PacketSize) - p->pos, 0);
00151       if (res == -1) {
00152         int err = GET_LAST_ERROR();
00153         if (err != EWOULDBLOCK) {
00154           /* Something went wrong... (104 is connection reset by peer) */
00155           if (err != 104) DEBUG(net, 0, "recv failed with error %d", err);
00156           this->CloseConnection();
00157           return NULL;
00158         }
00159         /* Connection would block, so stop for now */
00160         return NULL;
00161       }
00162       if (res == 0) {
00163         /* Client/server has left */
00164         this->CloseConnection();
00165         return NULL;
00166       }
00167       p->pos += res;
00168     }
00169 
00170     /* Read the packet size from the received packet */
00171     p->ReadRawPacketSize();
00172 
00173     if (p->size > SEND_MTU) {
00174       this->CloseConnection();
00175       return NULL;
00176     }
00177   }
00178 
00179   /* Read rest of packet */
00180   while (p->pos < p->size) {
00181     res = recv(this->sock, (char*)p->buffer + p->pos, p->size - p->pos, 0);
00182     if (res == -1) {
00183       int err = GET_LAST_ERROR();
00184       if (err != EWOULDBLOCK) {
00185         /* Something went wrong... (104 is connection reset by peer) */
00186         if (err != 104) DEBUG(net, 0, "recv failed with error %d", err);
00187         this->CloseConnection();
00188         return NULL;
00189       }
00190       /* Connection would block */
00191       return NULL;
00192     }
00193     if (res == 0) {
00194       /* Client/server has left */
00195       this->CloseConnection();
00196       return NULL;
00197     }
00198 
00199     p->pos += res;
00200   }
00201 
00202   /* Prepare for receiving a new packet */
00203   this->packet_recv = NULL;
00204 
00205   p->PrepareToRead();
00206   return p;
00207 }
00208 
00209 bool NetworkTCPSocketHandler::IsPacketQueueEmpty()
00210 {
00211   return this->packet_queue == NULL;
00212 }
00213 
00214 #endif /* ENABLE_NETWORK */

Generated on Tue Jan 5 21:02:55 2010 for OpenTTD by  doxygen 1.5.6