1 files changed, 25 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/com32/menu/drain.c b/contrib/syslinux-4.02/com32/menu/drain.c
new file mode 100644
index 0000000..60efd35
--- /dev/null
+++ b/contrib/syslinux-4.02/com32/menu/drain.c
@@ -0,0 +1,25 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/cpu.h>
+
+void drain_keyboard(void)
+{
+    /* Prevent "ghost typing" and keyboard buffer snooping */
+    volatile char junk;
+    int rv;
+
+    do {
+	rv = read(0, (char *)&junk, 1);
+    } while (rv > 0);
+
+    junk = 0;
+
+    cli();
+    *(volatile uint8_t *)0x419 = 0;	/* Alt-XXX keyboard area */
+    *(volatile uint16_t *)0x41a = 0x1e;	/* Keyboard buffer empty */
+    *(volatile uint16_t *)0x41c = 0x1e;
+    memset((void *)0x41e, 0, 32);	/* Clear the actual keyboard buffer */
+    sti();
+}