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#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/cpu.h>
#include <sys/module.h>

static int drain_init(void)
{
    return 0;			// Nothing to do; return success
}

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();
}

static void drain_exit(void)
{
    // Nothing to do
}

// Define entry and exit points.
MODULE_INIT(drain_init);
MODULE_EXIT(drain_exit);