kern_cons.c revision 10666
1/* 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1991 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: @(#)cons.c 7.2 (Berkeley) 5/9/91 39 * $Id: cons.c,v 1.33 1995/09/10 18:57:25 bde Exp $ 40 */ 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/conf.h> 45#include <sys/proc.h> 46#include <sys/tty.h> 47 48#include <machine/cons.h> 49#include <machine/stdarg.h> 50 51/* XXX this should be config(8)ed. */ 52#include "sc.h" 53#include "vt.h" 54#include "sio.h" 55static struct consdev constab[] = { 56#if NSC > 0 57 { sccnprobe, sccninit, sccngetc, sccncheckc, sccnputc }, 58#endif 59#if NVT > 0 60 { pccnprobe, pccninit, pccngetc, pccncheckc, pccnputc }, 61#endif 62#if NSIO > 0 63 { siocnprobe, siocninit, siocngetc, siocncheckc, siocnputc }, 64#endif 65 { 0 }, 66}; 67 68struct tty *constty = 0; /* virtual console output device */ 69struct tty *cn_tty; /* XXX: console tty struct for tprintf */ 70int cons_unavail = 0; /* XXX: 71 * physical console not available for 72 * input (i.e., it is in graphics mode) 73 */ 74 75static u_char cn_is_open; /* nonzero if logical console is open */ 76static u_char cn_phys_is_open; /* nonzero if physical console is open */ 77static d_close_t *cn_phys_close; /* physical device close function */ 78static d_open_t *cn_phys_open; /* physical device open function */ 79static struct consdev *cn_tab; /* physical console device info */ 80static struct tty *cn_tp; /* physical console tty struct */ 81 82#ifdef DEVFS 83#include <sys/kernel.h> 84#include <sys/devfsext.h> 85 86static void cndev_init __P((void *)); 87SYSINIT(cndev, SI_SUB_DEVFS, SI_ORDER_ANY, cndev_init, NULL) 88 89static void 90cndev_init(dummy) 91 void *dummy; 92{ 93 void * x; 94/* path name devsw minor type uid gid perm*/ 95 x=dev_add("/misc", "console", cnopen, 0, DV_CHR, 0, 0, 0640); 96} 97#endif /* DEVFS */ 98 99void 100cninit() 101{ 102 struct consdev *best_cp, *cp; 103 104 /* 105 * Find the first console with the highest priority. 106 */ 107 best_cp = NULL; 108 for (cp = constab; cp->cn_probe; cp++) { 109 (*cp->cn_probe)(cp); 110 if (cp->cn_pri > CN_DEAD && 111 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri)) 112 best_cp = cp; 113 } 114 115 /* 116 * If no console, give up. 117 */ 118 if (best_cp == NULL) { 119 cn_tab = best_cp; 120 return; 121 } 122 123 /* 124 * Initialize console, then attach to it. This ordering allows 125 * debugging using the previous console, if any. 126 * XXX if there was a previous console, then its driver should 127 * be informed when we forget about it. 128 */ 129 (*best_cp->cn_init)(best_cp); 130 cn_tab = best_cp; 131} 132 133void 134cninit_finish() 135{ 136 struct cdevsw *cdp; 137 138 if (cn_tab == NULL) 139 return; 140 141 /* 142 * Hook the open and close functions. 143 */ 144 cdp = &cdevsw[major(cn_tab->cn_dev)]; 145 cn_phys_close = cdp->d_close; 146 cdp->d_close = cnclose; 147 cn_phys_open = cdp->d_open; 148 cdp->d_open = cnopen; 149 cn_tp = (*cdp->d_devtotty)(cn_tab->cn_dev); 150 /* 151 * XXX there are too many tty pointers. cn_tty is only used for 152 * sysctl(CPU_CONSDEV) (not for tprintf like the above comment 153 * says). cn_tp in struct consdev hasn't been initialized 154 * (except statically to NULL) or used (except to initialize 155 * cn_tty to the wrong value) for a year or two. 156 */ 157 cn_tty = cn_tp; 158} 159 160int 161cnopen(dev, flag, mode, p) 162 dev_t dev; 163 int flag, mode; 164 struct proc *p; 165{ 166 dev_t cndev, physdev; 167 int retval; 168 169 if (cn_tab == NULL) 170 return (0); 171 cndev = cn_tab->cn_dev; 172 physdev = (major(dev) == major(cndev) ? dev : cndev); 173 retval = (*cn_phys_open)(physdev, flag, mode, p); 174 if (retval == 0) { 175 if (dev == cndev) 176 cn_phys_is_open = 1; 177 else if (physdev == cndev) 178 cn_is_open = 1; 179 } 180 return (retval); 181} 182 183int 184cnclose(dev, flag, mode, p) 185 dev_t dev; 186 int flag, mode; 187 struct proc *p; 188{ 189 dev_t cndev; 190 191 if (cn_tab == NULL) 192 return (0); 193 cndev = cn_tab->cn_dev; 194 if (dev == cndev) { 195 /* the physical device is about to be closed */ 196 cn_phys_is_open = 0; 197 if (cn_is_open) { 198 if (cn_tp) { 199 /* perform a ttyhalfclose() */ 200 /* reset session and proc group */ 201 cn_tp->t_pgrp = NULL; 202 cn_tp->t_session = NULL; 203 } 204 return (0); 205 } 206 } else if (major(dev) != major(cndev)) { 207 /* the logical console is about to be closed */ 208 cn_is_open = 0; 209 if (cn_phys_is_open) 210 return (0); 211 dev = cndev; 212 } 213 return ((*cn_phys_close)(dev, flag, mode, p)); 214} 215 216int 217cnread(dev, uio, flag) 218 dev_t dev; 219 struct uio *uio; 220 int flag; 221{ 222 if (cn_tab == NULL) 223 return (0); 224 dev = cn_tab->cn_dev; 225 return ((*cdevsw[major(dev)].d_read)(dev, uio, flag)); 226} 227 228int 229cnwrite(dev, uio, flag) 230 dev_t dev; 231 struct uio *uio; 232 int flag; 233{ 234 if (cn_tab == NULL) 235 return (0); 236 if (constty) 237 dev = constty->t_dev; 238 else 239 dev = cn_tab->cn_dev; 240 return ((*cdevsw[major(dev)].d_write)(dev, uio, flag)); 241} 242 243int 244cnioctl(dev, cmd, data, flag, p) 245 dev_t dev; 246 int cmd; 247 caddr_t data; 248 int flag; 249 struct proc *p; 250{ 251 int error; 252 253 if (cn_tab == NULL) 254 return (0); 255 /* 256 * Superuser can always use this to wrest control of console 257 * output from the "virtual" console. 258 */ 259 if (cmd == TIOCCONS && constty) { 260 error = suser(p->p_ucred, (u_short *) NULL); 261 if (error) 262 return (error); 263 constty = NULL; 264 return (0); 265 } 266 dev = cn_tab->cn_dev; 267 return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p)); 268} 269 270int 271cnselect(dev, rw, p) 272 dev_t dev; 273 int rw; 274 struct proc *p; 275{ 276 if (cn_tab == NULL) 277 return (1); 278 279 dev = cn_tab->cn_dev; 280 281 return ((*cdevsw[major(dev)].d_select)(dev, rw, p)); 282} 283 284int 285cngetc() 286{ 287 int c; 288 if (cn_tab == NULL) 289 return (0); 290 c = (*cn_tab->cn_getc)(cn_tab->cn_dev); 291 if (c == '\r') c = '\n'; /* console input is always ICRNL */ 292 return (c); 293} 294 295int 296cncheckc() 297{ 298 if (cn_tab == NULL) 299 return (0); 300 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev)); 301} 302 303void 304cnputc(c) 305 register int c; 306{ 307 if (cn_tab == NULL) 308 return; 309 if (c) { 310 if (c == '\n') 311 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 312 (*cn_tab->cn_putc)(cn_tab->cn_dev, c); 313 } 314} 315 316int 317pg(const char *p, ...) { 318 va_list args; 319 va_start(args, p); 320 printf("%r\n>", p, args); 321 return(cngetc()); 322} 323 324 325