root/sys/arch/alpha/stand/boot/devopen.c
/*      $OpenBSD: devopen.c,v 1.9 2023/01/16 07:29:35 deraadt Exp $     */
/*      $NetBSD: devopen.c,v 1.1 1995/11/23 02:39:37 cgd Exp $  */

/*-
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ralph Campbell.
 *
 * 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.
 *
 *      @(#)devopen.c   8.1 (Berkeley) 6/10/93
 */

#include <lib/libsa/stand.h>

/*
 * Decode the string 'fname', open the device and return the remaining
 * file name if any.
 */
int
devopen(f, fname, file)
        struct open_file *f;
        const char *fname;
        char **file;    /* out */
{
        register char *cp;
        register char *ncp;
        register struct devsw *dp;
        register int c, i;
        int ctlr = 0, unit = 0, part = 0;
        char namebuf[20];
        int rc;

        cp = (char *)fname;
        ncp = namebuf;

        /* look for a string like 'disk(0,0,0)bsd' */
        if (strchr(cp, '(')) {
                while ((c = *cp) != '\0') {
                        if (c == '(') {
                                cp++;
                                break;
                        }
                        if (ncp < namebuf + sizeof(namebuf) - 1)
                                *ncp++ = c;
                        cp++;
                }

                /* get controller number */
                if ((c = *cp) >= '0' && c <= '9') {
                        ctlr = c - '0';
                        c = *++cp;
                }

                if (c == ',') {
                        /* get SCSI device number */
                        if ((c = *++cp) >= '0' && c <= '9') {
                                unit = c - '0';
                                c = *++cp;
                        }

                        if (c == ',') {
                                /* get partition number */
                                if ((c = *++cp) >= '0' && c <= '9') {
                                        part = c - '0';
                                        c = *++cp;
                                }
                        }
                }
                if (c != ')')
                        goto defdev;
                cp++;
                *ncp = '\0';
        } else {
defdev:
                /* No valid device specification */
                cp = (char *)fname;
                ncp = namebuf;
                dp = devsw;
                ctlr = unit = part = 0;
                goto fnd;
        }

        for (dp = devsw, i = 0; i < ndevs; dp++, i++)
                if (dp->dv_name && strcmp(namebuf, dp->dv_name) == 0)
                        goto fnd;
        printf("Unknown device '%s'\nKnown devices are:", namebuf);
        for (dp = devsw, i = 0; i < ndevs; dp++, i++)
                if (dp->dv_name)
                        printf(" %s", dp->dv_name);
        printf("\n");
        return (ENXIO);

fnd:
        rc = (dp->dv_open)(f, ctlr, unit, part);
        if (rc)
                return (rc);

        f->f_dev = dp;
        if (file && *cp != '\0')
                *file = cp;
        return (0);
}