/*      $OpenBSD: cons.c,v 1.14 2010/05/09 15:30:28 jsg Exp $   */

/*
 * Copyright (c) 1988 University of Utah.
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * form: OpenBSD: cons.c,v 1.7 1996/04/21 22:19:48
 * from: OpenBSD: cninit.c,v 1.2 1996/03/30 02:03:45
 * from: Utah $Hdr: cons.c 1.7 92/01/21$
 *
 *      @(#)cons.c      8.2 (Berkeley) 1/12/94
 */

#include <sys/param.h>
#include "stand.h"
#include <dev/cons.h>

extern struct consdev constab[];

void
cninit(void)
{
        struct consdev *cp;

        /*
         * Collect information about all possible consoles
         * and find the one with highest priority
         */
        for (cp = constab; cp->cn_probe; cp++) {
                (*cp->cn_probe)(cp);
                if (cp->cn_pri != CN_DEAD &&
                    (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
                        cn_tab = cp;
        }
        /*
         * No console, we can handle it
         */
        if ((cp = cn_tab) == NULL)
                return;
        /*
         * Turn on console
         */
        (*cp->cn_init)(cp);
}

int
cnset(dev_t dev)
{
        struct consdev *cp;

        /*
         * Look for the specified console device and use it.
         */
        for (cp = constab; cp->cn_probe; cp++) {
                if (major(cp->cn_dev) == major(dev)) {
                        /* short-circuit noop */
                        if (cp == cn_tab && cp->cn_dev == dev)
                                return (0);
                        if (cp->cn_pri != CN_DEAD) {
                                cn_tab = cp;
                                cp->cn_dev = dev;
                                /* Turn it on.  */
                                (*cp->cn_init)(cp);
                                return (0);
                        }
                        break;
                }
        }
        return (1);
}

int
cngetc(void)
{
        if (cn_tab == NULL)
                return (0);
        return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
}

void
cnputc(int c)
{
        if (cn_tab != NULL && c) {
                (*cn_tab->cn_putc)(cn_tab->cn_dev, c);
                if (c == '\n')
                        (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
        }
}

int
cnischar(void)
{
        if (cn_tab != NULL)
                return ((*cn_tab->cn_getc)(cn_tab->cn_dev|0x80));
        return 0;
}