/* $Id: ioperm.c,v 1.2 2008/09/12 21:14:28 kostik Exp kostik $ */

#include <machine/sysarch.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static const unsigned int port_num = 0x130;

unsigned char
inb(unsigned int port)
{
	unsigned char data;

	__asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
	return (data);
}

void
sigbus_handler(int signo)
{

	fprintf(stderr, "Got SIGBUS\n");
	exit(0);
}

int
main(int argc, char *argv[])
{
	struct sigaction sa;
	unsigned int length1;
	int enable1;

	if (i386_get_ioperm(port_num, &length1, &enable1) == -1) {
		fprintf(stderr, "get 1: %s\n", strerror(errno));
		return (1);
	}
	if (length1 != 0 && enable1 != 0) {
		fprintf(stderr, "enable1: enabled\n");
		return (1);
	}
	if (i386_set_ioperm(port_num, 1, 1) == -1) {
		fprintf(stderr, "set 1: %s\n", strerror(errno));
		return (1);
	}
	inb(port_num);
	if (i386_set_ioperm(port_num, 1, 0) == -1) {
		fprintf(stderr, "set 2: %s\n", strerror(errno));
		return (1);
	}
	if (i386_get_ioperm(port_num, &length1, &enable1) == -1) {
		fprintf(stderr, "get 1: %s\n", strerror(errno));
		return (1);
	}
	if (enable1 != 0) {
		fprintf(stderr, "enable2: enabled\n");
		return (1);
	}
	fprintf(stderr, "And now we should get SIGBUS\n");
	memset(&sa, 0, sizeof(sa));
	sa.sa_handler = sigbus_handler;
	if (sigaction(SIGBUS, &sa, NULL) == -1) {
		fprintf(stderr, "sigaction(SIGBUS): %s\n", strerror(errno));
		return (1);
	}
	inb(port_num);
	
	return (0);
}