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/*
* Copyright (C) 2011-2012 Christian Beier <dontmind@freeshell.org>
* Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
*
* This 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 software 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 software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
/*
* listen.c - listen for incoming connections
*/
#ifdef __STRICT_ANSI__
#define _BSD_SOURCE
#endif
#if LIBVNCSERVER_HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#ifdef WIN32
#include <winsock2.h>
#else // #ifdef WIN32
#include <sys/wait.h>
#include <sys/utsname.h>
#endif
#if LIBVNCSERVER_HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#include <rfb/rfbclient.h>
/*
* listenForIncomingConnections() - listen for incoming connections from
* servers, and fork a new process to deal with each connection.
*/
void
listenForIncomingConnections(rfbClient* client)
{
#ifdef WIN32
/* FIXME */
rfbClientErr("listenForIncomingConnections on MinGW32 NOT IMPLEMENTED\n");
return;
#else
int listenSocket = RFB_INVALID_SOCKET, listen6Socket = RFB_INVALID_SOCKET;
fd_set fds;
client->listenSpecified = TRUE;
listenSocket = ListenAtTcpPortAndAddress(client->listenPort, client->listenAddress);
if (listenSocket == RFB_INVALID_SOCKET)
return;
rfbClientLog("%s -listen: Listening on port %d\n",
client->programName,client->listenPort);
rfbClientLog("%s -listen: Command line errors are not reported until "
"a connection comes in.\n", client->programName);
#ifdef LIBVNCSERVER_IPv6 /* only try that if we're IPv6-capable, otherwise we may try to bind to the same port which would make all that listening fail */
/* only do IPv6 listen of listen6Port is set */
if (client->listen6Port != RFB_INVALID_SOCKET)
{
listen6Socket = ListenAtTcpPortAndAddress(client->listen6Port, client->listen6Address);
if (listen6Socket == RFB_INVALID_SOCKET)
return;
rfbClientLog("%s -listen: Listening on IPV6 port %d\n",
client->programName,client->listenPort);
rfbClientLog("%s -listen: Command line errors are not reported until "
"a connection comes in.\n", client->programName);
}
#endif
while (TRUE) {
int r;
/* reap any zombies */
int status, pid;
while ((pid= wait4(-1, &status, WNOHANG, (struct rusage *)0))>0);
/* TODO: callback for discard any events (like X11 events) */
FD_ZERO(&fds);
if(listenSocket != RFB_INVALID_SOCKET)
FD_SET(listenSocket, &fds);
if(listen6Socket != RFB_INVALID_SOCKET)
FD_SET(listen6Socket, &fds);
r = select(rfbMax(listenSocket, listen6Socket)+1, &fds, NULL, NULL, NULL);
if (r > 0) {
if (FD_ISSET(listenSocket, &fds))
client->sock = AcceptTcpConnection(client->listenSock);
else if (FD_ISSET(listen6Socket, &fds))
client->sock = AcceptTcpConnection(client->listen6Sock);
if (client->sock == RFB_INVALID_SOCKET)
return;
if (!SetNonBlocking(client->sock))
return;
/* Now fork off a new process to deal with it... */
switch (fork()) {
case -1:
rfbClientErr("fork\n");
return;
case 0:
/* child - return to caller */
rfbCloseSocket(listenSocket);
rfbCloseSocket(listen6Socket);
return;
default:
/* parent - go round and listen again */
rfbCloseSocket(client->sock);
break;
}
}
}
#endif
}
/*
* listenForIncomingConnectionsNoFork() - listen for incoming connections
* from servers, but DON'T fork, instead just wait timeout microseconds.
* If timeout is negative, block indefinitely.
* Returns 1 on success (there was an incoming connection on the listen socket
* and we accepted it successfully), -1 on error, 0 on timeout.
*/
int
listenForIncomingConnectionsNoFork(rfbClient* client, int timeout)
{
fd_set fds;
struct timeval to;
int r;
to.tv_sec= timeout / 1000000;
to.tv_usec= timeout % 1000000;
client->listenSpecified = TRUE;
if (client->listenSock == RFB_INVALID_SOCKET)
{
client->listenSock = ListenAtTcpPortAndAddress(client->listenPort, client->listenAddress);
if (client->listenSock == RFB_INVALID_SOCKET)
return -1;
rfbClientLog("%s -listennofork: Listening on port %d\n",
client->programName,client->listenPort);
rfbClientLog("%s -listennofork: Command line errors are not reported until "
"a connection comes in.\n", client->programName);
}
#ifdef LIBVNCSERVER_IPv6 /* only try that if we're IPv6-capable, otherwise we may try to bind to the same port which would make all that listening fail */
/* only do IPv6 listen of listen6Port is set */
if (client->listen6Port != RFB_INVALID_SOCKET && client->listen6Sock == RFB_INVALID_SOCKET)
{
client->listen6Sock = ListenAtTcpPortAndAddress(client->listen6Port, client->listen6Address);
if (client->listen6Sock == RFB_INVALID_SOCKET)
return -1;
rfbClientLog("%s -listennofork: Listening on IPV6 port %d\n",
client->programName,client->listenPort);
rfbClientLog("%s -listennofork: Command line errors are not reported until "
"a connection comes in.\n", client->programName);
}
#endif
FD_ZERO(&fds);
if(client->listenSock != RFB_INVALID_SOCKET)
FD_SET(client->listenSock, &fds);
if(client->listen6Sock != RFB_INVALID_SOCKET)
FD_SET(client->listen6Sock, &fds);
if (timeout < 0)
r = select(rfbMax(client->listenSock, client->listen6Sock) +1, &fds, NULL, NULL, NULL);
else
r = select(rfbMax(client->listenSock, client->listen6Sock) +1, &fds, NULL, NULL, &to);
if (r > 0)
{
if (FD_ISSET(client->listenSock, &fds))
client->sock = AcceptTcpConnection(client->listenSock);
else if (FD_ISSET(client->listen6Sock, &fds))
client->sock = AcceptTcpConnection(client->listen6Sock);
if (client->sock == RFB_INVALID_SOCKET)
return -1;
if (!SetNonBlocking(client->sock))
return -1;
if(client->listenSock != RFB_INVALID_SOCKET) {
rfbCloseSocket(client->listenSock);
client->listenSock = RFB_INVALID_SOCKET;
}
if(client->listen6Sock != RFB_INVALID_SOCKET) {
rfbCloseSocket(client->listen6Sock);
client->listen6Sock = RFB_INVALID_SOCKET;
}
return r;
}
/* r is now either 0 (timeout) or -1 (error) */
return r;
}
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