cons.c revision 1.40.4.2
1 /* $NetBSD: cons.c,v 1.40.4.2 2001/09/18 19:13:49 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; 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 if (devvp->v_rdev == cndev) { 92 /* 93 * This causes cnopen() to be called recursively, which 94 * is generally a bad thing. It is often caused when 95 * dev == 0 and cn_dev has not been set, but was probably 96 * initialised to 0. 97 */ 98 panic("cnopen: cn_tab->cn_dev == dev\n"); 99 } 100 101 if (vfinddev(cndev, VCHR, &vp) == 0) { 102 error = cdevvp(cndev, &vp); 103 if (error != 0) 104 return error; 105 } else 106 vref(vp); 107 devvp->v_devcookie = vp; 108 109 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 110 error = VOP_OPEN(vp, mode, p->p_ucred, p, NULL); 111 VOP_UNLOCK(vp, 0); 112 if (error != 0) 113 vrele(vp); 114 return error; 115 } 116 117 int 118 cnclose(devvp, flag, mode, p) 119 struct vnode *devvp; 120 int flag, mode; 121 struct proc *p; 122 { 123 struct vnode *vp; 124 int error; 125 126 if (cn_tab == NULL) 127 return (0); 128 129 vp = devvp->v_devcookie; 130 131 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 132 error = VOP_CLOSE(vp, flag, p->p_ucred, p); 133 vput(vp); 134 135 return error; 136 } 137 138 int 139 cnread(devvp, uio, flag) 140 struct vnode *devvp; 141 struct uio *uio; 142 int flag; 143 { 144 int error; 145 struct vnode *vp; 146 struct proc *p = uio->uio_procp; 147 148 /* 149 * If we would redirect input, punt. This will keep strange 150 * things from happening to people who are using the real 151 * console. Nothing should be using /dev/console for 152 * input (except a shell in single-user mode, but then, 153 * one wouldn't TIOCCONS then). 154 */ 155 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 156 return 0; 157 else if (cn_tab == NULL) 158 return ENXIO; 159 160 vp = devvp->v_devcookie; 161 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 162 error = VOP_READ(vp, uio, flag, p->p_ucred); 163 VOP_UNLOCK(vp, 0); 164 165 return error; 166 } 167 168 int 169 cnwrite(devvp, uio, flag) 170 struct vnode *devvp; 171 struct uio *uio; 172 int flag; 173 { 174 int error; 175 struct vnode *vp; 176 struct proc *p = uio->uio_procp; 177 178 /* 179 * Redirect output, if that's appropriate. 180 * If there's no real console, return ENXIO. 181 */ 182 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 183 vp = constty->t_devvp; 184 else if (cn_tab == NULL) 185 return ENXIO; 186 else 187 vp = devvp->v_devcookie; 188 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 189 error = VOP_WRITE(vp, uio, flag, p->p_ucred); 190 VOP_UNLOCK(vp, 0); 191 return error; 192 } 193 194 void 195 cnstop(tp, flag) 196 struct tty *tp; 197 int flag; 198 { 199 200 } 201 202 int 203 cnioctl(devvp, cmd, data, flag, p) 204 struct vnode *devvp; 205 u_long cmd; 206 caddr_t data; 207 int flag; 208 struct proc *p; 209 { 210 int error; 211 struct vnode *vp; 212 213 /* 214 * Superuser can always use this to wrest control of console 215 * output from the "virtual" console. 216 */ 217 if (cmd == TIOCCONS && constty != NULL) { 218 error = suser(p->p_ucred, (u_short *) NULL); 219 if (error) 220 return (error); 221 constty = NULL; 222 return (0); 223 } 224 225 /* 226 * Redirect the ioctl, if that's appropriate. 227 * Note that strange things can happen, if a program does 228 * ioctls on /dev/console, then the console is redirected 229 * out from under it. 230 */ 231 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 232 vp = constty->t_devvp; 233 else if (cn_tab == NULL) 234 return ENXIO; 235 else 236 vp = devvp->v_devcookie; 237 238 return VOP_IOCTL(vp, cmd, data, flag, p->p_ucred, p); 239 } 240 241 /*ARGSUSED*/ 242 int 243 cnpoll(devvp, events, p) 244 struct vnode *devvp; 245 int events; 246 struct proc *p; 247 { 248 struct vnode *vp; 249 250 /* 251 * Redirect the poll, if that's appropriate. 252 * I don't want to think of the possible side effects 253 * of console redirection here. 254 */ 255 if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE)) 256 vp = constty->t_devvp; 257 else if (cn_tab == NULL) 258 return ENXIO; 259 else 260 vp = devvp->v_devcookie; 261 262 return VOP_POLL(vp, events, p); 263 } 264 265 int 266 cngetc() 267 { 268 269 if (cn_tab == NULL) 270 return (0); 271 return ((*cn_tab->cn_getc)(cn_tab->cn_dev)); 272 } 273 274 int 275 cngetsn(cp, size) 276 char *cp; 277 int size; 278 { 279 char *lp; 280 int c, len; 281 282 cnpollc(1); 283 284 lp = cp; 285 len = 0; 286 for (;;) { 287 c = cngetc(); 288 switch (c) { 289 case '\n': 290 case '\r': 291 printf("\n"); 292 *lp++ = '\0'; 293 cnpollc(0); 294 return (len); 295 case '\b': 296 case '\177': 297 case '#': 298 if (len) { 299 --len; 300 --lp; 301 printf("\b \b"); 302 } 303 continue; 304 case '@': 305 case 'u'&037: /* CTRL-u */ 306 len = 0; 307 lp = cp; 308 printf("\n"); 309 continue; 310 default: 311 if (len + 1 >= size || c < ' ') { 312 printf("\007"); 313 continue; 314 } 315 printf("%c", c); 316 ++len; 317 *lp++ = c; 318 } 319 } 320 } 321 322 void 323 cnputc(c) 324 int c; 325 { 326 327 if (cn_tab == NULL) 328 return; 329 330 if (c) { 331 (*cn_tab->cn_putc)(cn_tab->cn_dev, c); 332 if (c == '\n') 333 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 334 } 335 } 336 337 void 338 cnpollc(on) 339 int on; 340 { 341 static int refcount = 0; 342 343 if (cn_tab == NULL) 344 return; 345 if (!on) 346 --refcount; 347 if (refcount == 0) 348 (*cn_tab->cn_pollc)(cn_tab->cn_dev, on); 349 if (on) 350 ++refcount; 351 } 352 353 void 354 nullcnpollc(dev, on) 355 dev_t dev; 356 int on; 357 { 358 359 } 360 361 void 362 cnbell(pitch, period, volume) 363 u_int pitch, period, volume; 364 { 365 366 if (cn_tab == NULL || cn_tab->cn_bell == NULL) 367 return; 368 (*cn_tab->cn_bell)(cn_tab->cn_dev, pitch, period, volume); 369 } 370
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