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| #include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <assert.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <fcntl.h>
#define BUF_SIZE 1024
static int connfd;
void sig_urg( int sig )
{
int save_errno = errno;
char buffer[ BUF_SIZE ];
memset( buffer, '\0', BUF_SIZE );
int ret = recv( connfd, buffer, BUF_SIZE-1, MSG_OOB );
printf( "got %d bytes of oob data '%s'\n", ret, buffer );
errno = save_errno;
}
void addsig( int sig, void ( *sig_handler )( int ) )
{
struct sigaction sa;
memset( &sa, '\0', sizeof( sa ) );
sa.sa_handler = sig_handler;
sa.sa_flags |= SA_RESTART;
sigfillset( &sa.sa_mask );
assert( sigaction( sig, &sa, NULL ) != -1 );
}
int main( int argc, char* argv[] )
{
if( argc <= 2 )
{
printf( "usage: %s ip_address port_number\n", basename( argv[0] ) );
return 1;
}
const char* ip = argv[1];
int port = atoi( argv[2] );
struct sockaddr_in address;
bzero( &address, sizeof( address ) );
address.sin_family = AF_INET;
inet_pton( AF_INET, ip, &address.sin_addr );
address.sin_port = htons( port );
int sock = socket( PF_INET, SOCK_STREAM, 0 );
assert( sock >= 0 );
int ret = bind( sock, ( struct sockaddr* )&address, sizeof( address ) );
assert( ret != -1 );
ret = listen( sock, 5 );
assert( ret != -1 );
struct sockaddr_in client;
socklen_t client_addrlength = sizeof( client );
connfd = accept( sock, ( struct sockaddr* )&client, &client_addrlength );
if ( connfd < 0 )
{
printf( "errno is: %d\n", errno );
}
else
{
addsig( SIGURG, sig_urg );
fcntl( connfd, F_SETOWN, getpid() );
char buffer[ BUF_SIZE ];
while( 1 )
{
memset( buffer, '\0', BUF_SIZE );
ret = recv( connfd, buffer, BUF_SIZE-1, 0 );
if( ret <= 0 )
{
break;
}
printf( "got %d bytes of normal data '%s'\n", ret, buffer );
}
close( connfd );
}
close( sock );
return 0;
}
|