Prevent from creating invalid cdr call log records

Signed-off-by: Grzegorz Sluja <grzegorz.sluja@iopsys.eu>

cdr/cdr_csv.c

@@ -338,7 +338,7 @@ static int csv_log(struct ast_cdr *cdr)
 	char buf[1024];
 
 	/* Don't create records for CDRs where dcontext = "hangup" */
-	if (!strcasecmp(cdr->dcontext, "hangup")) {
+	if (ast_strlen_zero(cdr->dcontext) || !strcasecmp(cdr->dcontext, "hangup") || ast_strlen_zero(cdr->dstchannel)) {
 		return 0;
 	}