Better log output to debug problems sending very large email messages.

Wait double the inactivity timeout value for the acknowledgement (250 response)
when sending messages to avoid sending duplicates (an observed problem
with very large messages/attachments).

src/sbbs3/mailsrvr.c

@@ -401,8 +401,8 @@ static int sockreadline(SOCKET socket, char* buf, int len)
 
 		if(i<1) {
 			if(i==0) {
-				if((time(NULL)-start)>startup->max_inactivity) {
-					lprintf(LOG_WARNING,"%04d !SOCKET INACTIVE",socket);
+				if(startup->max_inactivity && (time(NULL)-start)>startup->max_inactivity) {
+					lprintf(LOG_WARNING,"%04d !TIMEOUT in sockreadline (%u seconds):  INACTIVE SOCKET",socket,startup->max_inactivity);
 					return(-1);
 				}
 				continue;
@@ -433,8 +433,11 @@ static BOOL sockgetrsp(SOCKET socket, char* rsp, char *buf, int len)
 
 	while(1) {
 		rd = sockreadline(socket, buf, len);
-		if(rd<1) 
+		if(rd<1) {
+			if(rd==0)
+				lprintf(LOG_WARNING,"%04d !RECEIVED BLANK RESPONSE, Expected '%s'", socket, rsp);
 			return(FALSE);
+		}
 		if(buf[3]=='-')	{ /* Multi-line response */
 			if(startup->options&MAIL_OPT_DEBUG_RX_RSP) 
 				lprintf(LOG_DEBUG,"%04d RX: %s",socket,buf);
@@ -4264,6 +4267,7 @@ static void sendmail_thread(void* arg)
 	ulong		ip_addr;
 	ulong		dns;
 	ulong		lines;
+	ulong		bytes;
 	BOOL		success;
 	BOOL		first_cycle=TRUE;
 	SOCKET		sock=INVALID_SOCKET;
@@ -4739,16 +4743,22 @@ static void sendmail_thread(void* arg)
 				bounce(sock, &smb,&msg,err,/* immediate: */buf[0]=='5');
 				continue;
 			}
-			lprintf(LOG_DEBUG,"%04d SEND sending message text (%u bytes)"
-				,sock, strlen(msgtxt));
+			bytes=strlen(msgtxt);
+			lprintf(LOG_DEBUG,"%04d SEND sending message text (%u bytes) begin"
+				,sock, bytes);
 			lines=sockmsgtxt(sock,&msg,msgtxt,-1);
+			lprintf(LOG_DEBUG,"%04d SEND send of message text (%u bytes, %u lines) complete, waiting for acknowledgement (250)"
+				,sock, bytes, lines);
 			if(!sockgetrsp(sock,"250", buf, sizeof(buf))) {
-				remove_msg_intransit(&smb,&msg);
-				SAFEPRINTF3(err,badrsp_err,server,buf,"250");
-				bounce(sock, &smb,&msg,err,/* immediate: */buf[0]=='5');
-				continue;
+				/* Wait doublely-long for the acknowledgement */
+				if(buf[0] || !sockgetrsp(sock,"250", buf, sizeof(buf))) {
+					remove_msg_intransit(&smb,&msg);
+					SAFEPRINTF3(err,badrsp_err,server,buf,"250");
+					bounce(sock, &smb,&msg,err,/* immediate: */buf[0]=='5');
+					continue;
+				}
 			}
-			lprintf(LOG_INFO,"%04d SEND message transfer complete (%lu lines)", sock, lines);
+			lprintf(LOG_INFO,"%04d SEND message transfer complete (%u bytes, %lu lines)", sock, bytes, lines);
 
 			/* Now lets mark this message for deletion without corrupting the index */
 			msg.hdr.attr|=MSG_DELETE;
@@ -5488,9 +5498,9 @@ void DLLCALL mail_server(void* arg)
 				,server_socket, active_clients.value);
 			start=time(NULL);
 			while(active_clients.value) {
-				if(time(NULL)-start>startup->max_inactivity) {
-					lprintf(LOG_WARNING,"%04d !TIMEOUT waiting for %d active clients"
-						,server_socket, active_clients.value);
+				if(startup->max_inactivity && time(NULL)-start>startup->max_inactivity) {
+					lprintf(LOG_WARNING,"%04d !TIMEOUT (%u seconds) waiting for %d active clients"
+						,server_socket, startup->max_inactivity, active_clients.value);
 					break;
 				}
 				mswait(100);