emit more error messages, first increment

Adding error messages at very important places. While code
is far from perfect, this is very useful and should go into
the mail line ASAP. Will improve in follow-on commits.

see also rsyslog#130

src/relpsess.c

@@ -39,6 +39,8 @@
  * development.
  */
 #include "config.h"
+#include <stdio.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <ctype.h>
 #include <assert.h>
@@ -58,6 +60,36 @@ static relpRetVal relpSessCltDoDisconnect(relpSess_t *pThis);
 static relpRetVal relpSessFixCmdStates(relpSess_t *pThis);
 static relpRetVal relpSessSrvDoDisconnect(relpSess_t *pThis);
 
+/* helper to call onErr if set */
+static void
+callOnErr(const relpSess_t *__restrict__ const pThis,
+	char *__restrict__ const emsg,
+	const relpRetVal ecode)
+{
+	char objinfo[1024];
+	//pThis->pEngine->dbgprint("librelp: generic error: ecode %d, "
+		//"emsg '%s'\n", ecode, emsg);
+	if(pThis->pEngine->onErr != NULL) {
+#if 0 // TODO: FIXME
+		if(pThis->pSrv == NULL) { /* client */
+			snprintf(objinfo, sizeof(objinfo), "conn to srvr %s:%s",
+				 pThis->pClt->pSess->srvAddr,
+				 pThis->pClt->pSess->srvPort);
+		} else if(pThis->pRemHostIP == NULL) { /* server listener */
+			snprintf(objinfo, sizeof(objinfo), "lstn %s",
+				 pThis->pSrv->pLstnPort);
+		} else { /* server connection to client */
+			snprintf(objinfo, sizeof(objinfo), "lstn %s: conn to clt %s/%s",
+				 pThis->pSrv->pLstnPort, pThis->pRemHostIP,
+				 pThis->pRemHostName);
+		}
+		objinfo[sizeof(objinfo)-1] = '\0';
+#endif
+		pThis->pEngine->onErr(pThis->pUsr, "session", emsg, ecode);
+	}
+}
+
+
 /* helper to free permittedPeer structure */
 static inline void
 relpSessFreePermittedPeers(relpSess_t *pThis)
@@ -235,6 +267,7 @@ relpSessRcvData(relpSess_t *pThis)
 	CHKRet(relpTcpRcv(pThis->pTcp, rcvBuf, &lenBuf));
 
 	if(lenBuf == 0) {
+		callOnErr(pThis, "server closed relp session, session broken", RELP_RET_SESSION_BROKEN);
 		pThis->pEngine->dbgprint("server closed relp session %p, session broken\n", (void*)pThis);
 		/* even though we had a "normal" close, it is unexpected at this
 		 * stage. Consequently, we consider the session to be broken, because
@@ -390,6 +423,7 @@ relpSessAddUnacked(relpSess_t *pThis, relpSendbuf_t *pSendbuf)
 		ABORT_FINALIZE(RELP_RET_OUT_OF_MEMORY);
 
 	pUnackedLstEntry->pSendbuf = pSendbuf;
+pThis->pEngine->dbgprint("sess state %d, adding to unacked list: %s\n", relpSessGetSessState(pThis), pSendbuf->pData + (9 - pSendbuf->lenTxnr));
 
 	DLL_Add(pUnackedLstEntry, pThis->pUnackedLstRoot, pThis->pUnackedLstLast);
 	++pThis->lenUnackedLst;
@@ -842,6 +876,7 @@ relpSessConnect(relpSess_t *pThis, int protFamily, unsigned char *port, unsigned
 	CHKRet(relpOffersToString(pOffers, NULL, 0, &pszOffers, &lenOffers));
 	CHKRet(relpOffersDestruct(&pOffers));
 
+pThis->pEngine->dbgprint("sending open command\n");
 	CHKRet(relpSessRawSendCommand(pThis, (unsigned char*)"open", 4, pszOffers, lenOffers,
 				      relpSessCBrspOpen));
 	relpSessSetSessState(pThis, eRelpSessState_INIT_CMD_SENT);