src/network/TCPServer.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 #include <SqlNetworkHandler.h>
  24
  25 DbRetVal TCPServer::start()
  26 {
  27     DbRetVal rv = OK;
  28     if (port == 0 )
  29     {
  30         printError(ErrBadArg, "Set the port first before starting\n");
  31         return ErrBadArg;
  32     }
  33     struct sockaddr_in my_addr;
  34     if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
  35        printError(ErrOS, "Unable to create socket\n");
  36        return ErrOS;
  37     }
  38     my_addr.sin_family = AF_INET;
  39     my_addr.sin_port = htons(port);
  40     my_addr.sin_addr.s_addr = INADDR_ANY;
  41     memset(&(my_addr.sin_zero), '\0', 8);
  42     int on = 1;
  43     setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
  44                                    (char *)&on, sizeof(on) );
  45
  46
  47     if (bind(sockfd, (struct sockaddr *)&my_addr,
  48                     sizeof(struct sockaddr)) == -1) {
  49         printError(ErrOS, "bind failed for port %d",port);
  50         return ErrOS;
  51     }
  52     if (listen(sockfd, 10) == -1) {
  53         printError(ErrOS, "listen failed");
  54         return ErrOS;
  55     }
  56     return rv;
  57
  58 }
  59 DbRetVal TCPServer::stop()
  60 {
  61     DbRetVal rv = OK;
  62     close (sockfd);
  63     return rv;
  64 }
  65 DbRetVal TCPServer::handleClient()
  66 {
  67    printf("DEBUG::handling client\n");
  68    DbRetVal rv = OK;
  69    socklen_t addressLen = sizeof(struct sockaddr);
  70    clientfd = accept(sockfd, (struct sockaddr*) &clientAddress, (LENGTH*)&addressLen);
  71    int ret = os::fork();
  72    if (ret) {
  73        //parent
  74        close(clientfd);
  75        return OK;
  76    }else if (ret == 0) {
  77        int on = 1;
  78        setsockopt(clientfd, IPPROTO_TCP, TCP_NODELAY,
  79                                    (char *)&on, sizeof(on) );
  80
  81        //child
  82        int response = 1;
  83        int ret = os::send(clientfd, &response, 4, 0);
  84        if (ret == -1)
  85        {
  86            printError(ErrOS, "Unable to communicate to peer\n");
  87            return ErrOS;
  88        }
  89 //       printf("sent connect ack packet to client\n");
  90        fd_set fdset;
  91        struct timeval timeout;
  92        SqlNetworkHandler handler;
  93        handler.sockfd = clientfd;
  94        PacketHeader header;
  95        while(true) {
  96            FD_ZERO(&fdset);
  97            FD_SET(clientfd, &fdset);
  98            timeout.tv_sec = 5;
  99            timeout.tv_usec = 0;
 100            int ret = os::select(clientfd+1, &fdset, 0, 0, &timeout);
 101            if (ret > 0) {
 102 //                printf("something in fd\n");
 103                int numbytes = os::recv(clientfd,&header,sizeof(PacketHeader),0);
 104                if (!numbytes) {
 105                    close(clientfd);
 106                    handler.closeConnection();
 107                    exit(1);
 108                }
 109                if (numbytes == -1)
 110                {
 111                    printError(ErrOS, "Error reading from socket");
 112                    handler.closeConnection();
 113                    exit(1);
 114                }
 115 //               printf("HEADER says packet type is %d\n", header.packetType);
 116                char *buffer = NULL;
 117                if (header.packetType != SQL_NW_PKT_DISCONNECT &&
 118                    header.packetType != SQL_NW_PKT_COMMIT     &&
 119                    header.packetType != SQL_NW_PKT_ROLLBACK   &&
 120                    header.packetType != SQL_NW_PKT_FETCH      &&
 121                    header.packetType != SQL_NW_PKT_SHOWTABLES &&
 122                    header.packetType != SQL_NW_PKT_LASTAIVAL )
 123                {
 124                    buffer = (char*) malloc(header.packetLength);
 125                    numbytes = os::recv(clientfd,buffer,header.packetLength,0);
 126                    if (numbytes == -1)
 127                    {
 128                        printError(ErrOS, "Error reading from socket");
 129                        handler.closeConnection();
 130                        exit(1);
 131                    }
 132                }
 133                ResponsePacket *rpkt = (ResponsePacket *)
 134                                                handler.process(header, buffer);
 135                if (rpkt != NULL) rv = handler.servePacket(header, rpkt);
 136            }
 137        }
 138    } else {
 139         printError(ErrOS, "Unable to fork new process");
 140         return ErrOS;
 141    }
 142    return OK;
 143 }