kern_cons.c revision 12678
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 1.37 1995/12/08 11:13:21 julian Exp $ 40 */ 41 42#include <sys/param.h> 43#ifdef DEVFS 44#include <sys/devfsext.h> 45#endif /*DEVFS*/ 46#include <sys/systm.h> 47#include <sys/conf.h> 48#include <sys/kernel.h> 49#include <sys/proc.h> 50#include <sys/tty.h> 51 52#include <machine/cons.h> 53#include <machine/stdarg.h> 54 55/* XXX this should be config(8)ed. */ 56#include "sc.h" 57#include "vt.h" 58#include "sio.h" 59static struct consdev constab[] = { 60#if NSC > 0 61 { sccnprobe, sccninit, sccngetc, sccncheckc, sccnputc }, 62#endif 63#if NVT > 0 64 { pccnprobe, pccninit, pccngetc, pccncheckc, pccnputc }, 65#endif 66#if NSIO > 0 67 { siocnprobe, siocninit, siocngetc, siocncheckc, siocnputc }, 68#endif 69 { 0 }, 70}; 71 72static d_open_t cnopen; 73static d_close_t cnclose; 74static d_read_t cnread; 75static d_write_t cnwrite; 76static d_ioctl_t cnioctl; 77static d_select_t cnselect; 78 79#define CDEV_MAJOR 0 80static struct cdevsw cn_cdevsw = 81 { cnopen, cnclose, cnread, cnwrite, /*0*/ 82 cnioctl, nullstop, nullreset, nodevtotty,/* console */ 83 cnselect, nommap, NULL, "console", NULL, -1 }; 84 85struct tty *constty = 0; /* virtual console output device */ 86struct tty *cn_tty; /* XXX: console tty struct for tprintf */ 87int cons_unavail = 0; /* XXX: 88 * physical console not available for 89 * input (i.e., it is in graphics mode) 90 */ 91 92static u_char cn_is_open; /* nonzero if logical console is open */ 93static u_char cn_phys_is_open; /* nonzero if physical console is open */ 94static d_close_t *cn_phys_close; /* physical device close function */ 95static d_open_t *cn_phys_open; /* physical device open function */ 96static struct consdev *cn_tab; /* physical console device info */ 97static struct tty *cn_tp; /* physical console tty struct */ 98#ifdef DEVFS 99void *cn_devfs_token; /* represents the devfs entry */ 100#endif /* DEVFS */ 101 102void 103cninit() 104{ 105 struct consdev *best_cp, *cp; 106 107 /* 108 * Find the first console with the highest priority. 109 */ 110 best_cp = NULL; 111 for (cp = constab; cp->cn_probe; cp++) { 112 (*cp->cn_probe)(cp); 113 if (cp->cn_pri > CN_DEAD && 114 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri)) 115 best_cp = cp; 116 } 117 118 /* 119 * If no console, give up. 120 */ 121 if (best_cp == NULL) { 122 cn_tab = best_cp; 123 return; 124 } 125 126 /* 127 * Initialize console, then attach to it. This ordering allows 128 * debugging using the previous console, if any. 129 * XXX if there was a previous console, then its driver should 130 * be informed when we forget about it. 131 */ 132 (*best_cp->cn_init)(best_cp); 133 cn_tab = best_cp; 134} 135 136void 137cninit_finish() 138{ 139 struct cdevsw *cdp; 140 141 if (cn_tab == NULL) 142 return; 143 144 /* 145 * Hook the open and close functions. 146 */ 147 cdp = &cdevsw[major(cn_tab->cn_dev)]; 148 cn_phys_close = cdp->d_close; 149 cdp->d_close = cnclose; 150 cn_phys_open = cdp->d_open; 151 cdp->d_open = cnopen; 152 cn_tp = (*cdp->d_devtotty)(cn_tab->cn_dev); 153 /* 154 * XXX there are too many tty pointers. cn_tty is only used for 155 * sysctl(CPU_CONSDEV) (not for tprintf like the above comment 156 * says). cn_tp in struct consdev hasn't been initialized 157 * (except statically to NULL) or used (except to initialize 158 * cn_tty to the wrong value) for a year or two. 159 */ 160 cn_tty = cn_tp; 161} 162 163static int 164cnopen(dev, flag, mode, p) 165 dev_t dev; 166 int flag, mode; 167 struct proc *p; 168{ 169 dev_t cndev, physdev; 170 int retval; 171 172 if (cn_tab == NULL) 173 return (0); 174 cndev = cn_tab->cn_dev; 175 physdev = (major(dev) == major(cndev) ? dev : cndev); 176 retval = (*cn_phys_open)(physdev, flag, mode, p); 177 if (retval == 0) { 178 if (dev == cndev) 179 cn_phys_is_open = 1; 180 else if (physdev == cndev) 181 cn_is_open = 1; 182 } 183 return (retval); 184} 185 186static int 187cnclose(dev, flag, mode, p) 188 dev_t dev; 189 int flag, mode; 190 struct proc *p; 191{ 192 dev_t cndev; 193 194 if (cn_tab == NULL) 195 return (0); 196 cndev = cn_tab->cn_dev; 197 if (dev == cndev) { 198 /* the physical device is about to be closed */ 199 cn_phys_is_open = 0; 200 if (cn_is_open) { 201 if (cn_tp) { 202 /* perform a ttyhalfclose() */ 203 /* reset session and proc group */ 204 cn_tp->t_pgrp = NULL; 205 cn_tp->t_session = NULL; 206 } 207 return (0); 208 } 209 } else if (major(dev) != major(cndev)) { 210 /* the logical console is about to be closed */ 211 cn_is_open = 0; 212 if (cn_phys_is_open) 213 return (0); 214 dev = cndev; 215 } 216 return ((*cn_phys_close)(dev, flag, mode, p)); 217} 218 219static int 220cnread(dev, uio, flag) 221 dev_t dev; 222 struct uio *uio; 223 int flag; 224{ 225 if (cn_tab == NULL) 226 return (0); 227 dev = cn_tab->cn_dev; 228 return ((*cdevsw[major(dev)].d_read)(dev, uio, flag)); 229} 230 231static int 232cnwrite(dev, uio, flag) 233 dev_t dev; 234 struct uio *uio; 235 int flag; 236{ 237 if (cn_tab == NULL) 238 return (0); 239 if (constty) 240 dev = constty->t_dev; 241 else 242 dev = cn_tab->cn_dev; 243 return ((*cdevsw[major(dev)].d_write)(dev, uio, flag)); 244} 245 246static int 247cnioctl(dev, cmd, data, flag, p) 248 dev_t dev; 249 int cmd; 250 caddr_t data; 251 int flag; 252 struct proc *p; 253{ 254 int error; 255 256 if (cn_tab == NULL) 257 return (0); 258 /* 259 * Superuser can always use this to wrest control of console 260 * output from the "virtual" console. 261 */ 262 if (cmd == TIOCCONS && constty) { 263 error = suser(p->p_ucred, (u_short *) NULL); 264 if (error) 265 return (error); 266 constty = NULL; 267 return (0); 268 } 269 dev = cn_tab->cn_dev; 270 return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p)); 271} 272 273static int 274cnselect(dev, rw, p) 275 dev_t dev; 276 int rw; 277 struct proc *p; 278{ 279 if (cn_tab == NULL) 280 return (1); 281 282 dev = cn_tab->cn_dev; 283 284 return ((*cdevsw[major(dev)].d_select)(dev, rw, p)); 285} 286 287int 288cngetc() 289{ 290 int c; 291 if (cn_tab == NULL) 292 return (0); 293 c = (*cn_tab->cn_getc)(cn_tab->cn_dev); 294 if (c == '\r') c = '\n'; /* console input is always ICRNL */ 295 return (c); 296} 297 298int 299cncheckc() 300{ 301 if (cn_tab == NULL) 302 return (0); 303 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev)); 304} 305 306void 307cnputc(c) 308 register int c; 309{ 310 if (cn_tab == NULL) 311 return; 312 if (c) { 313 if (c == '\n') 314 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 315 (*cn_tab->cn_putc)(cn_tab->cn_dev, c); 316 } 317} 318 319int 320pg(const char *p, ...) { 321 va_list args; 322 va_start(args, p); 323 printf("%r\n>", p, args); 324 return(cngetc()); 325} 326 327static cn_devsw_installed = 0; 328 329static void 330cn_drvinit(void *unused) 331{ 332 dev_t dev; 333 334 if( ! cn_devsw_installed ) { 335 dev = makedev(CDEV_MAJOR,0); 336 cdevsw_add(&dev,&cn_cdevsw,NULL); 337 cn_devsw_installed = 1; 338#ifdef DEVFS 339 cn_devfs_token = devfs_add_devsw( 340 "/", 341 "console", 342 &cn_cdevsw, 343 0, 344 DV_CHR, 345 0, 346 0, 347 0640); 348#endif 349 } 350} 351 352SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL) 353 354 355