Catch attempts to print NULL strings

diff --git a/src/core/vsprintf.c b/src/core/vsprintf.c
index 42bd510..e225d48 100644 (file)
--- a/src/core/vsprintf.c
+++ b/src/core/vsprintf.c
@@ -219,6 +219,8 @@ size_t vcprintf ( struct printf_context *ctx, const char *fmt, va_list args ) {
                        cputchar ( ctx, va_arg ( args, unsigned int ) );
                } else if ( *fmt == 's' ) {
                        ptr = va_arg ( args, char * );
+                       if ( ! ptr )
+                               ptr = "<NULL>";
                } else if ( *fmt == 'p' ) {
                        intptr_t ptrval;