/ *
** Writing: Nothing
* Source: www.20cn.net
** Note: Please indicate the reposted source
* /
#include
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INT M_MAINID = 0; // Main Process ID
INT m_listensocket = 0; // Saard socket
Char M_ConnectAddr [256] = {0}; // destination address
Char m_connectport [256] = {0}; // Target Port
/ *
** Function Name: getListensocket
** Function function: Generate listening socket
** Incoming Parameters: Port: Listening Port
** Outlet Parameters: None
** Reference function: no
** Return Value: Listening Socket, indicating that the generated socket failed, and the other set
** Note: None
* /
INT GetListensocket (int port)
{
Struct SockAddr_in M_Lisaddr = {0};
INT m_socket = 0;
INT M_ADDRLEN = SizeOf (struct sockaddr_in);
// Configure port information
m_lisaddr.sin_family = af_INet;
M_Lisaddr.sin_Port = HTONS (port);
m_lisaddr.sin_addr.s_addr = incdr_any;
// Create a socket
IF ((m_socket = socket (AF_INET, SOCK_STREAM, 0) <0)
{
// Creating a socket failed
Return 0;
}
// Binding socket
IF (bind (m_socket, (sockaddr *) & m_lisaddr, m_addrlen) <0)
{
// Binding socket failed
Close (m_socket);
Return 0;
}
// Listening socket
IF (Listen (M_Socket, 5))
{
// Listening socket failed
Close (m_socket);
Return 0;
}
// Listening socket generation success
Return m_socket;
}
/ *
** Function Name: getConnectSocket
** Function function: Generate connection socket
** Introduction parameters: PServeraddd: Connection address PServerport: Connection port
** Outlet Parameters: None
** Reference function: no
** Return Value: Connecting socket, indicating that the generated socket failed, and other set
** Note: None
* /
Int getConnectSocket (Char * PServeraddr, Char * PServerport)
{
Struct SockAddr_in m_serveraddr = {0};
INT M_ADDRLEN = SizeOf (struct sockaddr_in);
INT m_socket = 0;
// Initialize connection information
m_serveraddr.sin_addr.s_un.s_addr = inet_addr; m_serveraddr.sin_port = htons (atoi (atoi (pserverport);
m_serveradddr.sin_family = af_INET;
// Create a send socket
m_socket = socket (AF_INET, SOCK_STREAM, 0);
IF (m_socket <= 0)
{
//failure
Return NULL;
}
/ / Connect the client computer
IF (Connect (m_socket, (sockaddr *) & m_serveradddr, m_addrlen) <0)
{
Close (m_socket);
Return NULL;
}
//connection succeeded
Return m_socket;
}
/ *
** Function Name: Transsocket
** Function function: Complete the socket data forwarding
** Introduction parameters: m_sendsocket: Send socket M_Recvsocket: Receive socket
** Outlet Parameters: None
** Reference function: no
** Return value: no
** Note: Reverse completion of the full duplex
* /
Void Transsocket (int m_sendsocket, int m_recvsocket)
{
CHAR M_BUF [512 * 1024] = {0};
INT RET = 0;
FD_set readset;
Struct TimeValTM = {0};
TM.TV_SEC = 3600 * 24;
FD_ZERO (& Readset);
FD_set (M_Recvsocket, & Readset);
While (1)
{
IF ((SELECT (M_Recvsocket 1, & Readset, NULL, NULL, & TM)
<= 0)))
{
// error
Break;
}
IF (! fd_isset (m_recvsocket, & readset) Continue;
RET = Recv (M_Recvsocket, M_BUF, 512 * 1024 - 1, 0);
IF (RET <0)
{
// error
Break;
}
Send (m_sendsocket, m_buf, ret, 0);
}
Close (m_sendsocket);
Close (M_Recvsocket);
}
/ *
** Function Name: SocketTrans
** Function function: Work main function, complete data forwarding, new process start
** Introduction parameters: m_sendsocket: Send socket M_Recvsocket: Receive socket
** Outlet Parameters: None
** Reference function: no
** Return value: no
** Note: Reverse completion of the full duplex
* /
Void sockettrans ()
{
Struct SockAddr_in M_WORKADDR = {0};
INT m_191socket = 0;
INT m_147socket = 0;
INT M_WORKADDRLEN = 0;
/ / Start the task
While (1)
{
/ / Accept 147 connection
m_workaddrlen = sizeof (struct sockaddr_in);
m_147socket = accept (m_listensocket,
(SockAddr *) & m_workaddr, & m_workaddrlen;
// Check the legality of socket
IF (M_147Socket <0) Continue;
// Connect 191
M_191socket = getConnectSocket (m_connectaddr, m_connectport); if (m_191socket == null)
{
Close (M_147Socket);
CONTINUE;
}
int RET = fork ();
IF (RET <0)
{
// Establish a new process failed
Printf ("" Fatal Error, Unable to establish a new process! / n ");
Fflush (stdout);
Close (m_191socket);
Close (M_147Socket);
Break;
}
Else IF (RET == 0)
{
// Turn off the original port
Close (m_listensocket);
/ / Establish a second sub-process to prevent zombie process
Ret = fork ();
IF (RET <0)
{
Close (m_191socket);
Close (M_147Socket);
_exit (0);
}
Else IF (RET == 0)
{
// Receive process
Transsocket (M_191 Socket, M_147Socket);
_exit (0);
}
Ret = fork ();
IF (RET <0)
{
Close (m_191socket);
Close (M_147Socket);
_exit (0);
}
Else IF (RET == 0)
{
// Sending Process
Transsocket (M_147Socket, M_191Socket);
_exit (0);
}
Close (m_191socket);
Close (M_147Socket);
_exit (0);
}
// Waiting for the end of the sub-thread
Close (m_191socket);
Close (M_147Socket);
Waitpid (RET, NULL, 0);
}
}
/ *
** Function Name: SIG_USR
** Function function: process signal processing function
** Incoming parameters: no
** Outlet Parameters: None
** Reference function: no
** Return value: no
** Note: Test Process Termination Event
* /
Static void Sig_USR (Int Signo)
{
Close (m_listensocket);
IF (m_mainid == getpid ())
Kill (0, SIGKILL);
exit (0);
}
Static void Sig_ign (int Signo)
{
FPRINTF (stderr, "signalr% d catched, ignoring / n", sIGNO);
}
INT daemon_init ()
{
PID_T PID;
IF ((pID = for ()) <0) {
Return -1;
} else if (pID! = 0) {
exit (0);
}
setsid ();
Umask (0);
Return 0;
}
/ *
** Function Name: main
** Function function: Process main function
** Incoming parameters: no
** Outlet Parameters: None
** Reference function: makefilepath, getMyinitinfo, SocketTrans
** Return value: no
** Note: Receive process principles for customers
* /
Int main (int Argc, char * argv [])
{
// Check the legality of parameters
IF (argc! = 4)
{
Printf ("format: local port destination address destination port / n");
Fflush (stdout);
Return 0;
}
Daemon_init ();
// Register signal event
Signal (SIGTERM, SIG_USR);
Signal (SIGINT, SIG_USR);
Signal (SIGQUIT, SIG_USR); SIGNAL (SIGPIPE, SIG_IGN);
Signal (SIGALRM, SIG_IGN);
Signal (SIGQUIT, SIG_IGN);
Signal (SIGFPE, SIG_IGN);
Signal (SIGILL, SIG_IGN);
Signal (SIGPIPE, SIG_IGN);
Signal (SIGSEGV, SIG_IGN);
Signal (SigTrap, SIG_IGN);
Signal (SIGTSTP, SIG_IGN);
// Take parameters
STRCPY (M_ConnectAddr, Argv [2]);
STRCPY (M_Connectport, Argv [3]);
// Get listening socket
M_Listensocket = GetListensocket (ATOI (ARGV [1]));
IF (m_listensocket == 0)
{
Printf ("Listening Port [% S] failed! / n", Argv [1]);
Fflush (stdout);
Return 0;
}
m_mainid = get pid ();
// Start file receiving listening thread
SocketTrans ();
Close (m_listensocket);
Return 0;
}
