source: lib/rtserver.c @ 53f8305

#include "rtserver.h"
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <time.h>
#include <netdb.h>
#include <netinet/in.h>
#include <errno.h>


/** Structure containing all the information necessary to run an rtserver */
struct rtserver_t {
        /** fd describing the listening socket */
        int connect_fd;
        /** set of client fds */
        fd_set rt_fds;
        /** the highest numbered fd */
        int max_rtfds;
        /** sockaddr used to accept incoming connections */
        struct sockaddr_in * remote;
};

struct rtserver_t * rtserver_create (char * hostname, short port) {
        struct rtserver_t * rtserver = malloc(sizeof(struct rtserver_t));
        struct hostent *he;
        int yes = 1;
        
        FD_ZERO(&rtserver->rt_fds);

        if (hostname) {
                if ((he=gethostbyname(hostname)) == NULL) {
                        perror("gethostbyname");
                        return 0;
                }
        }
        
        if ((rtserver->connect_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
                perror("socket");
                return 0;
        }
        if (setsockopt(rtserver->connect_fd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
                perror("setsockopt");
                return 0;
        }
        rtserver->remote = calloc(1,sizeof(struct sockaddr_in));
        // Need to set up a listening server here
        bzero((char *) rtserver->remote, sizeof(rtserver->remote));
        rtserver->remote->sin_family = AF_INET;
        if (hostname)
                rtserver->remote->sin_addr = *((struct in_addr *)he->h_addr);
        else 
                rtserver->remote->sin_addr.s_addr = INADDR_ANY;
        rtserver->remote->sin_port = htons(port);

        if (bind(rtserver->connect_fd, (struct sockaddr *) rtserver->remote, sizeof(struct sockaddr_in)) < 0) {
                perror("bind");
                return 0;
        }

        if (listen(rtserver->connect_fd, 10) == -1) {
                perror("listen");
                return 0;
        }
        
        rtserver->max_rtfds = rtserver->connect_fd;

        return rtserver;
}

void rtserver_destroy (struct rtserver_t * rtserver) {
        int i;
        close(rtserver->connect_fd);

        for (i=1; i <= rtserver->max_rtfds; i++) {
                if (FD_ISSET(i, &rtserver->rt_fds)) {
                        close(i);
                }
        }
        
        free(rtserver->remote);
        free(rtserver);
}

int rtserver_checklisten (struct rtserver_t * rtserver) {
        struct timeval tv;
        int rt_fd = 0;
        fd_set current;
        int i;
        int sin_size = sizeof(struct sockaddr_in);
        
        tv.tv_sec = 0;
        tv.tv_usec = 0;
        
        FD_ZERO(&current);
        FD_SET(rtserver->connect_fd, &current);
        
        do {
                if (select(rtserver->max_rtfds + 1, &current, NULL, NULL,&tv) >=0 ) {
                        break;
                }
        }
        while (errno == EINTR);
        for (i = 0; i <= rtserver->max_rtfds; i++) {
                if (FD_ISSET(i, &current)) {
                        // Got something on the listening socket
                        if (i == rtserver->connect_fd) {
                                if ((rt_fd = accept(i, (struct sockaddr *) rtserver->remote,
                                                                &sin_size)) == -1) {
                                        perror("accept");
                                        return -1;
                                } else {
                                        printf("Client connected\n");
                                        FD_SET(rt_fd, &rtserver->rt_fds);
                                        if (rt_fd > rtserver->max_rtfds)
                                                rtserver->max_rtfds = rt_fd;
                                }
                        }
                }
        }
        return rt_fd;
}

int rtserver_sendclients (struct rtserver_t * rtserver, char * buffer, size_t len) {
        fd_set current;
        int i;
        int numbytes = 0;
        struct timeval tv;
        
        tv.tv_sec = 0;
        tv.tv_usec = 0;
        current = rtserver->rt_fds;

        if (select(rtserver->max_rtfds + 1, NULL, &current, NULL, &tv) == -1 ) {
                perror("select");
                return -1;
                
        }

        // Send the data to each ready client
        for (i = 0; i <= rtserver->max_rtfds; i++) {
                if (FD_ISSET(i, &current)) {
                        
                        // do write
#ifndef MSG_NOSIGNAL
#define MSG_NOSIGNAL 0
#endif

                        if ((numbytes = send(i, buffer, len, MSG_NOSIGNAL)) == -1) {
                                perror("send");
                                FD_CLR(i, &rtserver->rt_fds);
                                close(i);
                                numbytes = 0;                                
                        }
                }
        }
        return numbytes;
}