added capability for imtcp to activate keep-alive packets

at the socket layer.
reference: http://kb.monitorware.com/post20791.html

6 files changed, 30 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 1a0634d9..f4303d8d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 ---------------------------------------------------------------------------
 Version 5.9.0  [V5-DEVEL] (rgerhards), 2011-03-??
+- added capability for imtcp to activate keep-alive packets at the
+  socket layer.
+  reference: http://kb.monitorware.com/post20791.html
 - bugfix: do not open files with full privileges, if privs will be dropped
   This make the privilege drop code more bulletproof, but breaks Ubuntu's
   work-around for log files created by external programs with the wrong
diff --git a/doc/imtcp.html b/doc/imtcp.html
index b0aaa3c1..7653f601 100644
--- a/doc/imtcp.html
+++ b/doc/imtcp.html
@@ -55,6 +55,9 @@ so be prepared to wrangle with that!
 instructs imtcp to emit a message if the remote peer closes a connection.<br>
 <b>Important:</b> This directive is global to all listeners and must be given right
 after loading imtcp, otherwise it may have no effect.</li>
+<li><b>$InputTCPServerKeepAlive</b> &lt;on/<b>off</b>&gt;<br>
+enable of disable keep-alive packets at the tcp socket layer. The default is
+to disable them.</li>
 <li><b>$InputTCPServerRun</b> &lt;port&gt;<br>
 Starts a TCP server on selected port</li>
 <li><b>$InputTCPFlowControl</b> &lt;<b>on</b>/off&gt;<br>
diff --git a/plugins/imtcp/imtcp.c b/plugins/imtcp/imtcp.c
index 1a62d82e..c939e1d6 100644
--- a/plugins/imtcp/imtcp.c
+++ b/plugins/imtcp/imtcp.c
@@ -82,6 +82,7 @@ static permittedPeers_t *pPermPeersRoot = NULL;
 
 
 /* config settings */
+static int bKeepAlive = 0;		/* support keep-alive packets */
 static int iTCPSessMax = 200; /* max number of sessions */
 static int iTCPLstnMax = 20; /* max number of sessions */
 static int iStrmDrvrMode = 0; /* mode for stream driver, driver-dependent (0 mostly means plain tcp) */
@@ -192,6 +193,7 @@ static rsRetVal addTCPListener(void __attribute__((unused)) *pVal, uchar *pNewVa
 
 	if(pOurTcpsrv == NULL) {
 		CHKiRet(tcpsrv.Construct(&pOurTcpsrv));
+		CHKiRet(tcpsrv.SetKeepAlive(pOurTcpsrv, bKeepAlive));
 		CHKiRet(tcpsrv.SetSessMax(pOurTcpsrv, iTCPSessMax));
 		CHKiRet(tcpsrv.SetLstnMax(pOurTcpsrv, iTCPLstnMax));
 		CHKiRet(tcpsrv.SetCBIsPermittedHost(pOurTcpsrv, isPermittedHost));
@@ -289,6 +291,7 @@ static rsRetVal
 resetConfigVariables(uchar __attribute__((unused)) *pp, void __attribute__((unused)) *pVal)
 {
 	iTCPSessMax = 200;
+	bKeepAlive = 0;
 	iTCPLstnMax = 20;
 	iStrmDrvrMode = 0;
 	bUseFlowControl = 0;
@@ -327,6 +330,8 @@ CODEmodInit_QueryRegCFSLineHdlr
 	/* register config file handlers */
 	CHKiRet(omsdRegCFSLineHdlr(UCHAR_CONSTANT("inputtcpserverrun"), 0, eCmdHdlrGetWord,
 				   addTCPListener, NULL, STD_LOADABLE_MODULE_ID));
+	CHKiRet(omsdRegCFSLineHdlr(UCHAR_CONSTANT("inputtcpserverkeepalive"), 0, eCmdHdlrBinary,
+				   NULL, &bKeepAlive, STD_LOADABLE_MODULE_ID));
 	CHKiRet(omsdRegCFSLineHdlr(UCHAR_CONSTANT("inputtcpmaxsessions"), 0, eCmdHdlrInt,
 				   NULL, &iTCPSessMax, STD_LOADABLE_MODULE_ID));
 	CHKiRet(omsdRegCFSLineHdlr(UCHAR_CONSTANT("inputtcpmaxlisteners"), 0, eCmdHdlrInt,
diff --git a/runtime/strmsrv.c b/runtime/strmsrv.c
index f448cd4f..03691de6 100644
--- a/runtime/strmsrv.c
+++ b/runtime/strmsrv.c
@@ -767,7 +767,7 @@ static rsRetVal
 SetKeepAlive(strmsrv_t *pThis, int iVal)
 {
 	DEFiRet;
-	dbgprintf("keep-alive set to %d\n", iVal);
+	dbgprintf("strmsrv: keep-alive set to %d\n", iVal);
 	pThis->bUseKeepAlive = iVal;
 	RETiRet;
 }
diff --git a/tcpsrv.c b/tcpsrv.c
index fde6044d..4658555f 100644
--- a/tcpsrv.c
+++ b/tcpsrv.c
@@ -396,6 +396,10 @@ SessAccept(tcpsrv_t *pThis, tcpLstnPortList_t *pLstnInfo, tcps_sess_t **ppSess,
 		ABORT_FINALIZE(RS_RET_MAX_SESS_REACHED);
 	}
 
+	if(pThis->bUseKeepAlive) {
+		CHKiRet(netstrm.EnableKeepAlive(pNewStrm));
+	}
+
 	/* we found a free spot and can construct our session object */
 	CHKiRet(tcps_sess.Construct(&pSess));
 	CHKiRet(tcps_sess.SetTcpsrv(pSess, pThis));
@@ -864,6 +868,15 @@ SetUsrP(tcpsrv_t *pThis, void *pUsr)
 }
 
 static rsRetVal
+SetKeepAlive(tcpsrv_t *pThis, int iVal)
+{
+	DEFiRet;
+	dbgprintf("tcpsrv: keep-alive set to %d\n", iVal);
+	pThis->bUseKeepAlive = iVal;
+	RETiRet;
+}
+
+static rsRetVal
 SetOnMsgReceive(tcpsrv_t *pThis, rsRetVal (*OnMsgReceive)(tcps_sess_t*, uchar*, int))
 {
 	DEFiRet;
@@ -1042,6 +1055,7 @@ CODESTARTobjQueryInterface(tcpsrv)
 	pIf->create_tcp_socket = create_tcp_socket;
 	pIf->Run = Run;
 
+	pIf->SetKeepAlive = SetKeepAlive;
 	pIf->SetUsrP = SetUsrP;
 	pIf->SetInputName = SetInputName;
 	pIf->SetAddtlFrameDelim = SetAddtlFrameDelim;
diff --git a/tcpsrv.h b/tcpsrv.h
index 6c2bad45..9dc06e3e 100644
--- a/tcpsrv.h
+++ b/tcpsrv.h
@@ -48,6 +48,7 @@ struct tcpLstnPortList_s {
 /* the tcpsrv object */
 struct tcpsrv_s {
 	BEGINobjInstance;	/**< Data to implement generic object - MUST be the first data element! */
+	int bUseKeepAlive;	/**< use socket layer KEEPALIVE handling? */
 	netstrms_t *pNS;	/**< pointer to network stream subsystem */
 	int iDrvrMode;		/**< mode of the stream driver to use */
 	uchar *pszDrvrAuthMode;	/**< auth mode of the stream driver to use */
@@ -124,8 +125,10 @@ BEGINinterface(tcpsrv) /* name must also be changed in ENDinterface macro! */
 	rsRetVal (*SetbDisableLFDelim)(tcpsrv_t*, int);
 	/* added v10 -- rgerhards, 2011-04-01 */
 	rsRetVal (*SetUseFlowControl)(tcpsrv_t*, int);
+	/* added v11 -- rgerhards, 2011-05-09 */
+	rsRetVal (*SetKeepAlive)(tcpsrv_t*, int);
 ENDinterface(tcpsrv)
-#define tcpsrvCURR_IF_VERSION 10 /* increment whenever you change the interface structure! */
+#define tcpsrvCURR_IF_VERSION 11 /* increment whenever you change the interface structure! */
 /* change for v4:
  * - SetAddtlFrameDelim() added -- rgerhards, 2008-12-10
  * - SetInputName() added -- rgerhards, 2008-12-10