ex_network.c

Network module example.

Network module example

Author

Castagnier Mickael

Version

1.0

Date

26/05/2015

 
#include <stdio.h>
#include <errno.h>
 
#include "ex_network.h"
 
#define SERVER 0
#define CLIENT 1
 
int NB_ATTEMPTS=  3 ;
 
NETWORK *server = NULL,  
         *netw   = NULL   ; 
int mode = -1, ip_version = NETWORK_IPALL ;
 
static pthread_t netw_thr ;
 
void usage(void)
{
    fprintf( stderr, "     -v version\n"
             "     -V log level: LOG_INFO, LOG_NOTICE, LOG_ERR, LOG_DEBUG\n"
             "     -h help\n"
             "     -a serveur address name/ip to bind (server mode) (optionnal)\n"
             "     -s serveur address name/ip to connect (client mode)\n"
             "     -p port\n"
             "     -i [v4,v6] ip version (default support both ipv4 and ipv6 )\n" );
}
 
void process_args( int argc, char **argv, char **address, char **server, char **port, int *nb, int *ip_version )
{
    int getoptret = 0,
        log_level = LOG_ERR;  /* default log level */
 
    /* Arguments optionnels */
    /* -v version
     * -V log level
     * -h help
     * -a address name/ip to bind to (server mode, NULL if not specified)
     * -s serveur address name/ip to connect (client mode)
     * -p port
     * -i v4 ip version (default support both ipv4 and ipv6 )
     * -i v6 ip version (   "       "     "    "    "   "   )
     */
    if( argc == 1 )
    {
        fprintf( stderr,  "No arguments given, help:\n" );
        usage();
        exit( 1 );
    }
    while( ( getoptret = getopt( argc, argv, "hvs:V:p:n:i:a:" ) ) != EOF)
    {
        switch( getoptret )
        {
        case 'i' :
            if( !strcmp( "v4", optarg ) )
            {
                (*ip_version) = NETWORK_IPV4 ;
                n_log( LOG_NOTICE, "IPV4 selected" );
            }
            else if( !strcmp( "v6", optarg ) )
            {
                (*ip_version) = NETWORK_IPV6 ;
                n_log( LOG_NOTICE, "IPV6 selected" );
            }
            else
            {
                n_log( LOG_NOTICE, "IPV4/6 selected" );
            }
            break;
        case 'v' :
            fprintf( stderr, "Date de compilation : %s a %s.\n", __DATE__, __TIME__ );
            exit( 1 );
        case 'V' :
            if( !strncmp( "LOG_NULL", optarg, 8 ) )
            {
                log_level = LOG_NULL ;
            }
            else
            {
                if( !strncmp( "LOG_NOTICE", optarg, 10 ) )
                {
                    log_level = LOG_NOTICE;
                }
                else
                {
                    if( !strncmp( "LOG_INFO", optarg, 8 ) )
                    {
                        log_level = LOG_INFO;
                    }
                    else
                    {
                        if( !strncmp( "LOG_ERR", optarg, 7 ) )
                        {
                            log_level = LOG_ERR;
                        }
                        else
                        {
                            if( !strncmp( "LOG_DEBUG", optarg, 9 ) )
                            {
                                log_level = LOG_DEBUG;
                            }
                            else
                            {
                                fprintf( stderr, "%s n'est pas un niveau de log valide.\n", optarg );
                                exit( -1 );
                            }
                        }
                    }
                }
            }
            break;
        case 's' :
            (*server) = strdup( optarg );
            break ;
        case 'a' :
            (*address) = strdup( optarg );
            break ;
        case 'n' :
            (*nb) = atoi( optarg );
            break ;
        case 'p' :
            (*port) = strdup( optarg );
            break ;
        default :
        case '?' :
        {
            if( optopt == 'V' )
            {
                fprintf( stderr, "\n      Missing log level\n" );
            }
            else if( optopt == 'p' )
            {
                fprintf( stderr, "\n      Missing port\n" );
            }
            else if( optopt != 's' )
            {
                fprintf( stderr, "\n      Unknow missing option %c\n", optopt );
            }
            usage();
            exit( 1 );
        }
 
        case 'h' :
        {
            usage();
            exit( 1 );
        }
        }
    }
    set_log_level( log_level );
} /* void process_args( ... ) */
 
 
 
 
int main(int argc, char **argv)
{
 
    char *addr = NULL ;
    char *srv = NULL ;
    char *port = NULL ;
 
    set_log_level( LOG_DEBUG );
 
    /* processing args and set log_level */
    process_args( argc, argv, &addr, &srv, &port,&NB_ATTEMPTS, &ip_version );
 
    if( !port )
    {
        n_log( LOG_ERR, "No port given. Exiting." );
        exit( -1 );
    }
 
    if( srv && addr )
    {
        n_log( LOG_ERR, "Please specify only one of the following options: -a (server, addr to bind to) or -s (server on which to connect to)" );
    }
 
    if( srv )
    {
        n_log( LOG_INFO, "Client mode, connecting to %s:%s", srv, port );
        mode = CLIENT ;
    }
    else
    {
        n_log( LOG_INFO, "Server mode , waiting client on port %s", port );
        mode = SERVER ;
    }
 
#ifdef __linux__
    struct sigaction sa;
    sa.sa_handler = sigchld_handler; // reap all dead processes
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = SA_RESTART;
    if (sigaction(SIGCHLD, &sa, NULL) == -1)
    {
        perror("sigaction");
        exit(1);
    }
#endif
    if( mode == SERVER )
    {
        n_log( LOG_INFO, "Creating listening network for %s:%s %d", _str( addr ), _str( port ), ip_version );
        /* create listening network */
        if( netw_make_listening( &server, addr, port, 10, ip_version ) == FALSE )
        {
            n_log( LOG_ERR, "Fatal error with network initialization" );
            netw_unload();
            exit( -1 );
        }
        int it = 0 ;
        for( it = 0 ; it < NB_ATTEMPTS/2 ; it ++ )
        {
 
            n_log( LOG_INFO, "Blocking on accept..." );
            /* get any accepted client on a network */
            if ( !( netw = netw_accept_from( server ) ) )
            {
                n_log( LOG_ERR, "Error on accept" );
            }
            else
            {
                /* someone is connected. starting some dialog */
                int error = 0 ;
                int pthread_error = 0 ;
                errno = 0 ;
                pthread_error = pthread_create ( &netw_thr, NULL, &manage_client, (void *)netw );
                error = errno ;
                if( pthread_error != 0 )
                {
                    n_log( LOG_ERR, "Error creating client management pthread:%d , error: %s", pthread_error, strerror( error ) );
                    netw_unload();
                    exit( -1 );
                }
                pthread_join( netw_thr, NULL );
            }
        }
        /* testing with thread pool  && non blocking */
        int error = 0 ;
        THREAD_POOL *thread_pool = new_thread_pool( 2, 128 );
        while( it < NB_ATTEMPTS )
        {
            /* get any accepted client on a network */
            if ( ( netw = netw_accept_from_ex( server, 0, 0, 0, &error ) ) )
            {
                /* someone is connected. starting some dialog */
                if( add_threaded_process( thread_pool, &manage_client, (void *)netw, DIRECT_PROC ) == FALSE )
                {
                    n_log( LOG_ERR, "Error ading client management to thread pool" );
                }
                it ++ ;
            }
            else
            {
                n_log( LOG_DEBUG, "Waiting connections..." );
                u_sleep( 250000 );
            }
            refresh_thread_pool( thread_pool );
        }
        n_log( LOG_NOTICE, "Waiting thread_pool..." );
        wait_for_threaded_pool( thread_pool, 500000 );
        n_log( LOG_NOTICE, "Destroying thread_pool..." );
        destroy_threaded_pool( &thread_pool, 500000 );
        n_log( LOG_NOTICE, "Close waiting server" );
        netw_close( &server );
    }
    else if( mode == CLIENT )
    {
        for( int it = 1 ; it <= NB_ATTEMPTS ; it ++ )
        {
            if( netw_connect( &netw, srv, port, ip_version ) != TRUE )
            {
                /* there were some error when trying to connect */
                n_log( LOG_ERR, "Unable to connect to %s:%s", srv, port );
                netw_unload();
                exit( 1 );
            }
            n_log( LOG_NOTICE, "Attempt %d: Connected to %s:%s", it, srv, port );
 
            /* backgrounding network send / recv */
            netw_start_thr_engine( netw );
 
            N_STR *sended_data = NULL, *recved_data = NULL, *hostname = NULL, *tmpstr = NULL ;
 
            sended_data = char_to_nstr( "SENDING DATAS..." );
            send_net_datas( netw, sended_data );
 
            free_nstr( &sended_data );
 
            /* let's check for an answer: test each 250000 usec, with
             * a limit of 1000000 usec */
            n_log( LOG_INFO, "waiting for datas back from server..." );
            tmpstr = netw_wait_msg( netw, 25000, 10000000 );
 
            if( tmpstr )
            {
                get_net_datas( tmpstr, &hostname, &recved_data );
                n_log( LOG_NOTICE, "RECEIVED DATAS: %s - %s", recved_data ->data, hostname ->data );
                free_nstr( &tmpstr );
                free_nstr( &recved_data );
                free_nstr( &hostname );
            }
            else
            {
                n_log( LOG_ERR, "Error getting back answer from server" );
            }
            n_log( LOG_NOTICE, "Closing client in 5 seconds. See synchronisation on server side..." );
            netw_close( &netw );
        }
    }
 
    FreeNoLog( srv );
    FreeNoLog( addr );
    FreeNoLog( port )
 
    netw_unload();
 
    n_log( LOG_INFO, "Exiting network example" );
 
    exit( 0 );
} /* END_OF_MAIN() */