Avoid recursion on error.

Author: meisterT

judge/runguard.cc

@@ -308,12 +308,15 @@ void write_meta(const char *key, const char *format, ...)
 	va_start(ap,format);
 
 	if ( fprintf(metafile,"%s: ",key)<=0 ) {
+        outputmeta = 0;
 		error(0,"cannot write to file `%s'",metafilename);
 	}
 	if ( vfprintf(metafile,format,ap)<0 ) {
+        outputmeta = 0;
 		error(0,"cannot write to file `%s'(vfprintf)",metafilename);
 	}
 	if ( fprintf(metafile,"\n")<=0 ) {
+        outputmeta = 0;
 		error(0,"cannot write to file `%s'",metafilename);
 	}