src/network/UDPClient.cxx

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by Prabakaran Thirumalai   *
   3  *   praba_tuty@yahoo.com   *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  19  ***************************************************************************/
  20 #include <os.h>
  21 #include <CSql.h>
  22 #include <Network.h>
  23
  24 UDPClient::~UDPClient()
  25 {
  26    if (isConnectedFlag) disconnect();
  27 }
  28 DbRetVal UDPClient::send(NetworkPacketType type)
  29 {
  30     return send(type, NULL, 0);
  31 }
  32 DbRetVal UDPClient::send(NetworkPacketType type, int stmtid)
  33 {
  34     //TODO:
  35     return send(type, NULL, 0);
  36 }
  37 DbRetVal UDPClient::send(NetworkPacketType type, char *buf, int len)
  38 {
  39     DbRetVal rv = OK;
  40     //printf("NW:UDP Send\n");
  41     void* totalBuffer = malloc(sizeof(PacketHeader)+ len);
  42     //PacketHeader *hdr= (PacketHeader*) totalBuffer;
  43     PacketHeader *hdr=  new PacketHeader();
  44     hdr->packetType = type;
  45     hdr->packetLength = len;
  46     hdr->srcNetworkID = networkid;
  47     hdr->version = 1;
  48     memcpy(((char*)totalBuffer) + sizeof(PacketHeader) , buf, len);
  49
  50 /*
  51     int numbytes =sendto(sockfd, totalBuffer, sizeof(PacketHeader)+ len, 0,
  52                 (struct sockaddr *)&srvAddr, sizeof(struct sockaddr));
  53
  54     if (numbytes== -1) {
  55         printError(ErrOS,"Unable to send the packet\n");
  56         return ErrOS;
  57     }
  58 */
  59     int numbytes=0;
  60     if ((numbytes=sendto(sockfd, (const char*)hdr, sizeof(PacketHeader), 0,
  61            (struct sockaddr *)&srvAddr, sizeof(struct sockaddr))) == -1) {
  62         printError(ErrOS, "Unable to send the packet\n");
  63         return ErrOS;
  64     }
  65     //printf("Sent bytes %d\n", numbytes);
  66     if ((numbytes=sendto(sockfd, buf, len, 0,
  67            (struct sockaddr *)&srvAddr, sizeof(struct sockaddr))) == -1) {
  68         printError(ErrOS, "Unable to send the packet\n");
  69         return ErrOS;
  70     }
  71     //printf("Sent bytes %d\n", numbytes);
  72     free(totalBuffer);
  73     return rv;
  74
  75 }
  76 DbRetVal UDPClient::receive()
  77 {
  78     //TODO:: resoibse timeout during socket read
  79     DbRetVal rv = OK;
  80     fd_set fdset; //TODO::Move it to UDPClient class
  81     FD_ZERO(&fdset);
  82     FD_SET(sockfd, &fdset);
  83     struct timeval timeout;
  84     timeout.tv_sec = Conf::config.getNetworkResponseTimeout();
  85     timeout.tv_usec = 0;
  86     int ret = os::select(sockfd+1, &fdset, 0, 0, &timeout);
  87     if (ret <= 0) {
  88         printError(ErrPeerTimeOut,"Response timeout for peer site\n");
  89         return ErrPeerTimeOut;
  90     }
  91
  92     int response =0;
  93     socklen_t len = sizeof(struct sockaddr);
  94     int numbytes = recvfrom(sockfd, (char*)&response, 4, 0,
  95                    (struct sockaddr *)&fromAddr, &len);
  96     if (numbytes !=4)
  97     {
  98        printf("Unable to receive response from peer\n");
  99        return ErrOS;
 100     }
 101     //printf("NW:UDP receive\n");
 102     if (response != 1) rv = ErrPeerResponse;
 103     if(srvAddr.sin_addr.s_addr != fromAddr.sin_addr.s_addr)
 104     {
 105         printf("Packet received from unknown source\n");
 106         rv = ErrPeerResponse;
 107     }
 108     //printf("Response rv %d\n", rv);
 109     return rv;
 110 }
 111 DbRetVal UDPClient::connect()
 112 {
 113     printf("NW:UDP connect %s %d %d\n", hostName, port, networkid);
 114
 115     //TODO::send endian to the peer site
 116     //do not do endian conversion here. it will be done at the server side
 117     DbRetVal rv = OK;
 118     isConnectedFlag = false;
 119     struct hostent *he;
 120     int numbytes;
 121     if ((he=gethostbyname(hostName)) == NULL) { // get the host info
 122         printError(ErrOS,"Unable to get the peer host name\n");
 123         return ErrOS;
 124     }
 125     if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
 126         printError(ErrOS,"Unable to create socket to peer host name\n");
 127         return ErrOS;
 128     }
 129     srvAddr.sin_family = AF_INET; // host byte order
 130     srvAddr.sin_port = htons(port); // short, network byte order
 131     srvAddr.sin_addr = *((struct in_addr *)he->h_addr);
 132     memset(&(srvAddr.sin_zero), '\0', 8); // zero the rest of the struct
 133     printf("NW:UDP connecting\n");
 134     PacketHeader *hdr=  new PacketHeader();
 135     hdr->packetType = NW_PKT_CONNECT;
 136     hdr->packetLength = 0;
 137     hdr->srcNetworkID =
 138     hdr->version = 1;
 139     if ((numbytes=sendto(sockfd, (const char*) hdr, sizeof(PacketHeader), 0,
 140            (struct sockaddr *)&srvAddr, sizeof(struct sockaddr))) == -1) {
 141         printError(ErrOS, "Unable to send the packet\n");
 142         return ErrOS;
 143     }
 144     printf("Sent bytes %d\n", numbytes);
 145
 146     fd_set fdset;
 147     FD_ZERO(&fdset);
 148     FD_SET(sockfd, &fdset);
 149     struct timeval timeout;
 150     timeout.tv_sec = Conf::config.getNetworkConnectTimeout();
 151     timeout.tv_usec = 0;
 152     int ret = os::select(sockfd+1, &fdset, 0, 0, &timeout);
 153     if (ret <= 0) {
 154         printError(ErrPeerTimeOut,"Response timeout for peer site\n");
 155         return ErrPeerTimeOut;
 156     }
 157
 158     int response =0;
 159     socklen_t len = sizeof(struct sockaddr);
 160     numbytes = recvfrom(sockfd, (char*)&response, 4, 0,
 161                    (struct sockaddr *)&fromAddr,  &len);
 162     if (numbytes !=4)
 163     {
 164        printf("Unable to receive response from peer\n");
 165        return ErrOS;
 166     }
 167     if (response != 1) return ErrPeerResponse;
 168     isConnectedFlag = true;
 169     printf("NW:UDP connected\n");
 170     return OK;
 171 }
 172
 173 DbRetVal UDPClient::disconnect()
 174 {
 175     if (isConnectedFlag)
 176        printf("NW:UDP disconnect\n");
 177
 178     isConnectedFlag = false;
 179     return OK;
 180 }