1 /* $OpenBSD: cninit.c,v 1.11 2011/06/23 16:02:33 tedu Exp $ */ 2 /* $NetBSD: cninit.c,v 1.2 1995/04/11 22:08:10 pk Exp $ */ 3 4 /* 5 * Copyright (c) 1988 University of Utah. 6 * Copyright (c) 1990, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * the Systems Programming Group of the University of Utah Computer 11 * Science Department. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: Utah $Hdr: cons.c 1.7 92/01/21$ 38 * 39 * @(#)cons.c 8.2 (Berkeley) 1/12/94 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/proc.h> 45 #include <sys/buf.h> 46 #include <sys/ioctl.h> 47 #include <sys/tty.h> 48 #include <sys/file.h> 49 #include <sys/conf.h> 50 #include <sys/vnode.h> 51 52 #include <dev/cons.h> 53 54 struct consdev *cn_tab = NULL; 55 56 void 57 cninit(void) 58 { 59 struct consdev *cp; 60 61 /* 62 * Collect information about all possible consoles 63 * and find the one with highest priority. 64 */ 65 for (cp = constab; cp->cn_probe; cp++) { 66 (*cp->cn_probe)(cp); 67 if (cp->cn_pri != CN_DEAD && 68 (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri)) 69 cn_tab = cp; 70 } 71 72 /* 73 * No console, we can handle it. 74 */ 75 if ((cp = cn_tab) == NULL) 76 return; 77 78 /* 79 * Turn on console. 80 */ 81 (*cp->cn_init)(cp); 82 } 83 84 int 85 cnset(dev_t dev) 86 { 87 struct consdev *cp; 88 89 /* 90 * Look for the specified console device and use it. 91 */ 92 for (cp = constab; cp->cn_probe; cp++) { 93 if (major(cp->cn_dev) == major(dev)) { 94 /* Short-circuit noop. */ 95 if (cp == cn_tab && cp->cn_dev == dev) 96 return (0); 97 if (cp->cn_pri != CN_DEAD) { 98 cn_tab = cp; 99 cp->cn_dev = dev; 100 /* Turn it on. */ 101 (*cp->cn_init)(cp); 102 return (0); 103 } 104 break; 105 } 106 } 107 return (1); 108 } 109