iPDC-suite/DBServer/connections.c

272 lines
7.7 KiB
C
Executable File

/* -----------------------------------------------------------------------------
* connections.c
*
* iPDC - Phasor Data Concentrator
*
* Copyright (C) 2011 Nitesh Pandit
* Copyright (C) 2011 Kedar V. Khandeparkar
*
* This program 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; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Authors:
* Nitesh Pandit <panditnitesh@gmail.com>
* Kedar V. Khandeparkar <kedar.khandeparkar@gmail.com>
*
* ----------------------------------------------------------------------------- */
/* ---------------------------------------------------------------------------- */
/* Functions defined in connections.c */
/* -----------------------------------------------------------------------------*/
/* 1. void setup() */
/* 2. void* DB_udp() */
/* 3. void* DB_udphandler(void * udp_BUF) */
/* 4. void DB_process_UDP(char* udp_BUF) */
/* ---------------------------------------------------------------------------- */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>
#include <pthread.h>
#include "connections.h"
#include "parser.h"
#include "global.h"
/* ---------------------------------------------------------------- */
/* global variables */
/* ---------------------------------------------------------------- */
pthread_mutex_t mutex_on_buffer;
/* ---------------------------------------------------------------------------- */
/* FUNCTION setup(): */
/* ---------------------------------------------------------------------------- */
void setup(){
printf("Entering DBServer setup()\n");
/* MySQL data base parameters */
server = "localhost";
user = "root";
password = "root"; /* Change this password value, if not the same in your case? */
database = "iPDC";
/* MySQL data base connection */
conn_data = mysql_init(NULL);
conn_cfg = mysql_init(NULL);
if(conn_data == NULL) {
printf("No sufficient memory\n");
exit(1);
}
if(conn_cfg == NULL) {
printf("No sufficient memory\n");
exit(1);
}
/* Connect to database */
if (!mysql_real_connect(conn_data, server,
user, password, database, 0, NULL, 0)) {
fprintf(stderr, "%s\n", mysql_error(conn_data));
exit(1);
}
if (!mysql_real_connect(conn_cfg, server,
user, password, database, 0, NULL, 0)) {
fprintf(stderr, "%s\n", mysql_error(conn_cfg));
exit(1);
}
/* Create UDP socket and bind to port */
int yes;
if ((DB_sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
perror("socket");
exit(1);
} else {
printf("DB Socket:Sucessfully created\n");
}
if (setsockopt(DB_sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
perror("setsockopt");
exit(1);
}
DB_server_addr.sin_family = AF_INET; // host byte order
DB_server_addr.sin_port = htons(DBPORT); // short, network byte order
DB_server_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP
memset(&(DB_server_addr.sin_zero),'\0', 8); // zero the rest of the struct
if (bind(DB_sockfd, (struct sockaddr *)&DB_server_addr,
sizeof(DB_server_addr)) == -1) {
perror("bind");
exit(1);
} else {
printf("DB Socket Bind :Sucessfull\n");
}
printf("\nDB Server Listening on port %d\n",DBPORT);
DB_addr_len = sizeof(struct sockaddr);
DB_udp();
mysql_close(conn_cfg);
mysql_close(conn_data);
}
/* ---------------------------------------------------------------------------- */
/* FUNCTION udp(): */
/* It creates a Pthread for each received UDP data. */
/* ---------------------------------------------------------------------------- */
void DB_udp(){
// UDP threads are created for each received UDP message in 'detached' mode. Thus allowing any number of threads to be created.
int err;
pthread_attr_t attr;
pthread_attr_init(&attr);
if((err = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED))) { // In the detached state, the thread resources are
// immediately freed when it terminates, but
perror(strerror(err)); // pthread_join(3) cannot be used to synchronize
exit(1); // on the thread termination.
}
if((err = pthread_attr_setschedpolicy(&attr,SCHED_FIFO))) { // Shed policy = SCHED_FIFO (realtime, first-in first-out)
perror(strerror(err));
exit(1);
}
/* UDP data Received */
while(1) {
if ((numbytes = recvfrom(DB_sockfd,buffer, MAXBUFLEN-1, 0,(struct sockaddr *)&their_addr, (socklen_t *)&DB_addr_len)) == -1) {
// Main if
perror("recvfrom");
exit(1);
} else { /* New datagram has been received */
pthread_t t;
int tt;
unsigned char *udp_BUF;
udp_BUF = malloc(MAXBUFLEN*sizeof(unsigned char));
if(!udp_BUF) {
printf("No space for udp_BUF\n");
exit(1);
}
printf("UDP Server got packet from %s\n",inet_ntoa(their_addr.sin_addr));
printf("packet is %d bytes long.\n",numbytes);
buffer[numbytes] = '\0';
/* Copy the udp_buf data to a local variable */
pthread_mutex_lock(&mutex_on_buffer);
copy_cbyc(udp_BUF,buffer,MAXBUFLEN);
memset(buffer, '\0', MAXBUFLEN);
pthread_mutex_unlock(&mutex_on_buffer);
/* Creates a new thread for each received UDP message */
if((tt = pthread_create(&t,&attr,DB_udphandler,(void *)udp_BUF))) {
perror(strerror(tt));
exit(1);
}
} // Main if ends
} // while ends
pthread_attr_destroy(&attr);
}
/* ---------------------------------------------------------------------------- */
/* FUNCTION udphandler(): */
/* It internally calls process_UDP(). */
/* ---------------------------------------------------------------------------- */
void* DB_udphandler(void * udp_BUF) {
DB_process_UDP((unsigned char*)udp_BUF);
free((unsigned char*)udp_BUF);
pthread_exit(NULL); /* Exit the thread once the task is done. */
}
/* ---------------------------------------------------------------------------- */
/* FUNCTION process_UDP(): */
/* This function Processes the frames as per their type(command, data, config). */
/* ---------------------------------------------------------------------------- */
void DB_process_UDP(unsigned char* udp_BUF){
int stat_status,i;
unsigned char c = udp_BUF[1];
c <<= 1;
c >>= 5;
if(c == 0x00){ /* If data frame */
printf("\nData frame reveived\n");
stat_status = dataparser(udp_BUF);
printf("Return from Data Parser\n");
} else if(c == 0x03) { /* If configuration frame */
printf("\nConfiguration frame reveived\n");
cfgparser(udp_BUF);
printf("Return from CFG\n");
} else {
printf("Erroneous frame\n");
}
fflush(stdout);
}
/**************************************** End of File *******************************************************/