better error checking in spopen signal handler (see 1107524)

git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1169 f882894a-f735-0410-b71e-b25c423dba1c

plugins/popen.c

@@ -243,8 +243,12 @@ static int openmax = 0;
 void
 popen_timeout_alarm_handler (int signo)
 {
+	int fh;
 	if (signo == SIGALRM) {
-		kill (childpid[fileno (child_process)], SIGKILL);
+		fh=fileno (child_process);
+		if(fh >= 0){
+			kill (childpid[fh], SIGKILL);
+		}
 		printf (_("CRITICAL - Plugin timed out after %d seconds\n"),
 						timeout_interval);
 		exit (STATE_CRITICAL);

plugins/popen.h

@@ -9,7 +9,7 @@ int spclose (FILE *);
 RETSIGTYPE popen_timeout_alarm_handler (int);
 
 extern unsigned int timeout_interval;
-pid_t *childpid;
-int *child_stderr_array;
-FILE *child_process;
-FILE *child_stderr;
+pid_t *childpid=NULL;
+int *child_stderr_array=NULL;
+FILE *child_process=NULL;
+FILE *child_stderr=NULL;