cons.c revision 1.40.4.4
1 /* $NetBSD: cons.c,v 1.40.4.4 2001/09/26 15:28:09 fvdl Exp $ */ 2 3 /* 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * from: Utah $Hdr: cons.c 1.7 92/01/21$ 41 * 42 * @(#)cons.c 8.2 (Berkeley) 1/12/94 43 */ 44 45 #include <sys/param.h> 46 #include <sys/proc.h> 47 #include <sys/user.h> 48 #include <sys/systm.h> 49 #include <sys/buf.h> 50 #include <sys/ioctl.h> 51 #include <sys/tty.h> 52 #include <sys/file.h> 53 #include <sys/conf.h> 54 #include <sys/vnode.h> 55 56 #include <miscfs/specfs/specdev.h> 57 58 #include <dev/cons.h> 59 60 struct tty *constty = NULL; /* virtual console output device */ 61 struct consdev *cn_tab; /* physical console device info */ 62 63 int 64 cnopen(devvp, mode, flag, p) 65 struct vnode *devvp; 66 int flag, mode; 67 struct proc *p; 68 { 69 int error; 70 dev_t cndev, rdev; 71 struct vnode *vp; 72 73 if (cn_tab == NULL) 74 return (0); 75 76 77 /* 78 * always open the 'real' console device, so we don't get nailed 79 * later. This follows normal device semantics; they always get 80 * open() calls. 81 */ 82 cndev = cn_tab->cn_dev; 83 if (cndev == NODEV) { 84 /* 85 * This is most likely an error in the console attach 86 * code. Panicing looks better than jumping into nowhere 87 * through cdevsw below.... 88 */ 89 panic("cnopen: cn_tab->cn_dev == NODEV\n"); 90 } 91 rdev = vdev_rdev(devvp); 92 if (rdev == cndev) { 93 /* 94 * This causes cnopen() to be called recursively, which 95 * is generally a bad thing. It is often caused when 96 * dev == 0 and cn_dev has not been set, but was probably 97 * initialised to 0. 98 */ 99 panic("cnopen: cn_tab->cn_dev == dev\n"); 100 } 101 102 if (vfinddev(cndev, VCHR, &vp) == 0) { 103 error = cdevvp(cndev, &vp); 104 if (error != 0) 105 return error; 106 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 107 } else 108 vget(vp, LK_EXCLUSIVE | LK_RETRY); 109 110 vdev_setprivdata(devvp, vp); 111 112 error = VOP_OPEN(vp, mode, p->p_ucred, p, NULL); 113 VOP_UNLOCK(vp, 0); 114 if (error != 0) 115 vrele(vp); 116 return error; 117 } 118 119 int 120 cnclose(devvp, flag, mode, p) 121 struct vnode *devvp; 122 int flag, mode; 123 struct proc *p; 124 { 125 struct vnode *vp; 126 int error; 127 128 if (cn_tab == NULL) 129 return (0); 130 131 vp = vdev_privdata(devvp); 132 133 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 134 error = VOP_CLOSE(vp, flag, p->p_ucred, p); 135 vput(vp); 136 137 return error; 138 } 139 140 int 141 cnread(devvp, uio, flag) 142 struct vnode *devvp; 143 struct uio *uio; 144 int flag; 145 { 146 int error; 147 struct vnode *vp; 148 struct proc *p = uio->uio_procp; 149 150 /* 151 * If we would redirect input, punt. This will keep strange 152 * things from happening to people who are using the real 153 * console. Nothing should be using /dev/console for 154 * input (except a shell in single-user mode, but then, 155 * one wouldn't TIOCCONS then). 156 */ 157 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 158 return 0; 159 else if (cn_tab == NULL) 160 return ENXIO; 161 162 vp = vdev_privdata(devvp); 163 164 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 165 error = VOP_READ(vp, uio, flag, p->p_ucred); 166 VOP_UNLOCK(vp, 0); 167 168 return error; 169 } 170 171 int 172 cnwrite(devvp, uio, flag) 173 struct vnode *devvp; 174 struct uio *uio; 175 int flag; 176 { 177 int error; 178 struct vnode *vp; 179 struct proc *p = uio->uio_procp; 180 181 /* 182 * Redirect output, if that's appropriate. 183 * If there's no real console, return ENXIO. 184 */ 185 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 186 vp = constty->t_devvp; 187 else if (cn_tab == NULL) 188 return ENXIO; 189 else 190 vp = vdev_privdata(devvp); 191 192 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 193 error = VOP_WRITE(vp, uio, flag, p->p_ucred); 194 VOP_UNLOCK(vp, 0); 195 return error; 196 } 197 198 void 199 cnstop(tp, flag) 200 struct tty *tp; 201 int flag; 202 { 203 204 } 205 206 int 207 cnioctl(devvp, cmd, data, flag, p) 208 struct vnode *devvp; 209 u_long cmd; 210 caddr_t data; 211 int flag; 212 struct proc *p; 213 { 214 int error; 215 struct vnode *vp; 216 217 /* 218 * Superuser can always use this to wrest control of console 219 * output from the "virtual" console. 220 */ 221 if (cmd == TIOCCONS && constty != NULL) { 222 error = suser(p->p_ucred, (u_short *) NULL); 223 if (error) 224 return (error); 225 constty = NULL; 226 return (0); 227 } 228 229 /* 230 * Redirect the ioctl, if that's appropriate. 231 * Note that strange things can happen, if a program does 232 * ioctls on /dev/console, then the console is redirected 233 * out from under it. 234 */ 235 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 236 vp = constty->t_devvp; 237 else if (cn_tab == NULL) 238 return ENXIO; 239 else 240 vp = vdev_privdata(devvp); 241 242 return VOP_IOCTL(vp, cmd, data, flag, p->p_ucred, p); 243 } 244 245 /*ARGSUSED*/ 246 int 247 cnpoll(devvp, events, p) 248 struct vnode *devvp; 249 int events; 250 struct proc *p; 251 { 252 struct vnode *vp; 253 254 /* 255 * Redirect the poll, if that's appropriate. 256 * I don't want to think of the possible side effects 257 * of console redirection here. 258 */ 259 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 260 vp = constty->t_devvp; 261 else if (cn_tab == NULL) 262 return ENXIO; 263 else 264 vp = vdev_privdata(devvp); 265 266 return VOP_POLL(vp, events, p); 267 } 268 269 int 270 cngetc() 271 { 272 273 if (cn_tab == NULL) 274 return (0); 275 return ((*cn_tab->cn_getc)(cn_tab->cn_dev)); 276 } 277 278 int 279 cngetsn(cp, size) 280 char *cp; 281 int size; 282 { 283 char *lp; 284 int c, len; 285 286 cnpollc(1); 287 288 lp = cp; 289 len = 0; 290 for (;;) { 291 c = cngetc(); 292 switch (c) { 293 case '\n': 294 case '\r': 295 printf("\n"); 296 *lp++ = '\0'; 297 cnpollc(0); 298 return (len); 299 case '\b': 300 case '\177': 301 case '#': 302 if (len) { 303 --len; 304 --lp; 305 printf("\b \b"); 306 } 307 continue; 308 case '@': 309 case 'u'&037: /* CTRL-u */ 310 len = 0; 311 lp = cp; 312 printf("\n"); 313 continue; 314 default: 315 if (len + 1 >= size || c < ' ') { 316 printf("\007"); 317 continue; 318 } 319 printf("%c", c); 320 ++len; 321 *lp++ = c; 322 } 323 } 324 } 325 326 void 327 cnputc(c) 328 int c; 329 { 330 331 if (cn_tab == NULL) 332 return; 333 334 if (c) { 335 (*cn_tab->cn_putc)(cn_tab->cn_dev, c); 336 if (c == '\n') 337 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 338 } 339 } 340 341 void 342 cnpollc(on) 343 int on; 344 { 345 static int refcount = 0; 346 347 if (cn_tab == NULL) 348 return; 349 if (!on) 350 --refcount; 351 if (refcount == 0) 352 (*cn_tab->cn_pollc)(cn_tab->cn_dev, on); 353 if (on) 354 ++refcount; 355 } 356 357 void 358 nullcnpollc(dev, on) 359 dev_t dev; 360 int on; 361 { 362 363 } 364 365 void 366 cnbell(pitch, period, volume) 367 u_int pitch, period, volume; 368 { 369 370 if (cn_tab == NULL || cn_tab->cn_bell == NULL) 371 return; 372 (*cn_tab->cn_bell)(cn_tab->cn_dev, pitch, period, volume); 373 } 374
Indexes created Sun Oct 19 22:09:57 GMT 2025