xref: /csrg-svn/sys/kern/tty.c (revision 903)
1 /*	tty.c	3.17	09/20/80	*/
2 
3 /*
4  * TTY subroutines common to more than one line discipline
5  */
6 #include "../h/param.h"
7 #include "../h/systm.h"
8 #include "../h/dir.h"
9 #include "../h/user.h"
10 #include "../h/tty.h"
11 #include "../h/proc.h"
12 #include "../h/mx.h"
13 #include "../h/inode.h"
14 #include "../h/file.h"
15 #include "../h/reg.h"
16 #include "../h/conf.h"
17 #include "../h/buf.h"
18 #include "../h/dk.h"
19 
20 char	partab[];
21 
22 /*
23  * When running dz's using only SAE (silo alarm) on input
24  * it is necessary to call dzrint() at clock interrupt time.
25  * This is unsafe unless spl5()s in tty code are changed to
26  * spl6()s to block clock interrupts.  Note that the dh driver
27  * currently in use works the same way as the dz, even though
28  * we could try to more intelligently manage its silo.
29  * Thus don't take this out if you have no dz's unless you
30  * change clock.c and dhtimer().
31  */
32 #define	spl5	spl6
33 
34 /*
35  * Input mapping table-- if an entry is non-zero, when the
36  * corresponding character is typed preceded by "\" the escape
37  * sequence is replaced by the table value.  Mostly used for
38  * upper-case only terminals.
39  */
40 
41 char	maptab[] ={
42 	000,000,000,000,000,000,000,000,
43 	000,000,000,000,000,000,000,000,
44 	000,000,000,000,000,000,000,000,
45 	000,000,000,000,000,000,000,000,
46 	000,'|',000,000,000,000,000,'`',
47 	'{','}',000,000,000,000,000,000,
48 	000,000,000,000,000,000,000,000,
49 	000,000,000,000,000,000,000,000,
50 	000,000,000,000,000,000,000,000,
51 	000,000,000,000,000,000,000,000,
52 	000,000,000,000,000,000,000,000,
53 	000,000,000,000,000,000,'~',000,
54 	000,'A','B','C','D','E','F','G',
55 	'H','I','J','K','L','M','N','O',
56 	'P','Q','R','S','T','U','V','W',
57 	'X','Y','Z',000,000,000,000,000,
58 };
59 
60 #define	OBUFSIZ	100
61 
62 /*
63  * set default control characters.
64  */
65 ttychars(tp)
66 register struct tty *tp;
67 {
68 
69 	tun.t_intrc = CINTR;
70 	tun.t_quitc = CQUIT;
71 	tun.t_startc = CSTART;
72 	tun.t_stopc = CSTOP;
73 	tun.t_eofc = CEOT;
74 	tun.t_brkc = CBRK;
75 	tp->t_erase = CERASE;
76 	tp->t_kill = CKILL;
77 /* begin local */
78 	tlun.t_suspc = CTRL(z);
79 	tlun.t_dsuspc = CTRL(y);
80 	tlun.t_rprntc = CTRL(r);
81 	tlun.t_flushc = CTRL(o);
82 	tlun.t_werasc = CTRL(w);
83 	tlun.t_lnextc = CTRL(v);
84 	tlun.t_lintr = CTRL(c);
85 	tlun.t_lerase = CTRL(h);
86 	tlun.t_lkill = CTRL(u);
87 	tp->t_local = 0;
88 	tp->t_lstate = 0;
89 /* end local */
90 }
91 
92 /*
93  * Wait for output to drain, then flush input waiting.
94  */
95 wflushtty(tp)
96 register struct tty *tp;
97 {
98 
99 	(void) spl5();
100 	while (tp->t_outq.c_cc && tp->t_state&CARR_ON) {
101 		(*tp->t_oproc)(tp);
102 		tp->t_state |= ASLEEP;
103 		sleep((caddr_t)&tp->t_outq, TTOPRI);
104 	}
105 	flushtty(tp, FREAD|FWRITE);
106 	(void) spl0();
107 }
108 
109 /*
110  * flush all TTY queues
111  */
112 flushtty(tp, rw)
113 register struct tty *tp;
114 {
115 	register s;
116 
117 	if (tp->t_line == NETLDISC)
118 		return;
119 	s = spl6();
120 	if (rw & FREAD) {
121 		while (getc(&tp->t_canq) >= 0)
122 			;
123 		wakeup((caddr_t)&tp->t_rawq);
124 	}
125 	if (rw & FWRITE) {
126 		wakeup((caddr_t)&tp->t_outq);
127 		tp->t_state &= ~TTSTOP;
128 		(*cdevsw[major(tp->t_dev)].d_stop)(tp);
129 		while (getc(&tp->t_outq) >= 0)
130 			;
131 	}
132 	if (rw & FREAD) {
133 		while (getc(&tp->t_rawq) >= 0)
134 			;
135 		tp->t_delct = 0;
136 		tp->t_rocount = 0;		/* local */
137 		tp->t_rocol = 0;
138 		tp->t_lstate = 0;
139 	}
140 	splx(s);
141 }
142 
143 /*
144  * Send stop character on input overflow.
145  */
146 ttyblock(tp)
147 register struct tty *tp;
148 {
149 	register x;
150 	x = tp->t_rawq.c_cc + tp->t_canq.c_cc;
151 	if (tp->t_rawq.c_cc > TTYHOG) {
152 		flushtty(tp, FREAD|FWRITE);
153 		tp->t_state &= ~TBLOCK;
154 	}
155 	if (x >= TTYHOG/2) {
156 		if (putc(tun.t_stopc, &tp->t_outq)==0) {
157 			tp->t_state |= TBLOCK;
158 			tp->t_char++;
159 			ttstart(tp);
160 		}
161 	}
162 }
163 
164 /*
165  * Restart typewriter output following a delay
166  * timeout.
167  * The name of the routine is passed to the timeout
168  * subroutine and it is called during a clock interrupt.
169  */
170 ttrstrt(tp)
171 register struct tty *tp;
172 {
173 
174 	tp->t_state &= ~TIMEOUT;
175 	ttstart(tp);
176 }
177 
178 /*
179  * Start output on the typewriter. It is used from the top half
180  * after some characters have been put on the output queue,
181  * from the interrupt routine to transmit the next
182  * character, and after a timeout has finished.
183  */
184 ttstart(tp)
185 register struct tty *tp;
186 {
187 	register s;
188 
189 	s = spl5();
190 	if((tp->t_state&(TIMEOUT|TTSTOP|BUSY)) == 0)
191 		(*tp->t_oproc)(tp);
192 	splx(s);
193 }
194 
195 /*
196  * Common code for tty ioctls.
197  */
198 ttioctl(com, tp, addr, dev, flag)
199 register struct tty *tp;
200 caddr_t addr;
201 {
202 	unsigned t;
203 	struct sgttyb iocb;
204 	struct clist tq;
205 	extern int nldisp;
206 	register c;
207 	int temp;
208 
209 	/*
210 	 * If the ioctl involves modification,
211 	 * insist on being able to write the device,
212 	 * and hang if in the background.
213 	 */
214 	switch(com) {
215 
216 	case TIOCHPCL:
217 	case TIOCFLUSH:
218 	case TIOCSETC:
219 	case TIOCSLTC:
220 	case TIOCSPGRP:
221 	case TIOCLBIS:
222 	case TIOCLBIC:
223 	case TIOCLSET:
224 	case TIOCSTI:
225 		if ((flag & FWRITE) == 0) {
226 			u.u_error = EBADF;
227 			return (1);
228 		}
229 		while (tp->t_line == NTTYDISC &&
230 		   u.u_procp->p_pgrp != tp->t_pgrp && tp == u.u_ttyp &&
231 		   (u.u_procp->p_flag&SVFORK) == 0 &&
232 		   u.u_signal[SIGTTOU] != SIG_IGN &&
233 		   u.u_signal[SIGTTOU] != SIG_HOLD &&
234 		   (u.u_procp->p_flag&SDETACH)==0) {
235 			gsignal(u.u_procp->p_pgrp, SIGTTOU);
236 			sleep((caddr_t)&lbolt, TTOPRI);
237 		}
238 		break;
239 	}
240 
241 	/*
242 	 * Process the ioctl.
243 	 */
244 	switch(com) {
245 
246 	/*
247 	 * Get discipline number
248 	 */
249 	case TIOCGETD:
250 		t = tp->t_line;
251 		if (copyout((caddr_t)&t, addr, sizeof(t)))
252 			u.u_error = EFAULT;
253 		break;
254 
255 	/*
256 	 * Set line discipline
257 	 */
258 	case TIOCSETD:
259 		if (copyin(addr, (caddr_t)&t, sizeof(t))) {
260 			u.u_error = EFAULT;
261 			break;
262 		}
263 		if (t >= nldisp) {
264 			u.u_error = ENXIO;
265 			break;
266 		}
267 		(void) spl5();
268 		if (tp->t_line)
269 			(*linesw[tp->t_line].l_close)(tp);
270 		if (t)
271 			(*linesw[t].l_open)(dev, tp, addr);
272 		if (u.u_error==0)
273 			tp->t_line = t;
274 		(void) spl0();
275 		break;
276 
277 	/*
278 	 * Prevent more opens on channel
279 	 */
280 	case TIOCEXCL:
281 		tp->t_state |= XCLUDE;
282 		break;
283 
284 	case TIOCNXCL:
285 		tp->t_state &= ~XCLUDE;
286 		break;
287 
288 	/*
289 	 * Set new parameters
290 	 */
291 	case TIOCSETP:
292 	case TIOCSETN:
293 		if (copyin(addr, (caddr_t)&iocb, sizeof(iocb))) {
294 			u.u_error = EFAULT;
295 			return(1);
296 		}
297 		(void) spl5();
298 		if (tp->t_line == 0) {
299 			if (com == TIOCSETP)
300 				wflushtty(tp);
301 			while (canon(tp)>=0)
302 				;
303 		} else if (tp->t_line == NTTYDISC) {
304 			if (tp->t_flags&RAW || iocb.sg_flags&RAW ||
305 			    com == TIOCSETP)
306 				wflushtty(tp);
307 			else if ((tp->t_flags&CBREAK) != (iocb.sg_flags&CBREAK)) {
308 				if (iocb.sg_flags & CBREAK) {
309 					catq(&tp->t_rawq, &tp->t_canq);
310 					tq = tp->t_rawq;
311 					tp->t_rawq = tp->t_canq;
312 					tp->t_canq = tq;
313 				} else {
314 					tp->t_local |= LPENDIN;
315 					if (tp->t_canq.c_cc)
316 						panic("ioccom canq");
317 					if (tp->t_chan)
318 						(void) sdata(tp->t_chan);
319 					else
320 						wakeup((caddr_t)&tp->t_rawq);
321 				}
322 			}
323 		}
324 		if ((tp->t_state&SPEEDS)==0) {
325 			tp->t_ispeed = iocb.sg_ispeed;
326 			tp->t_ospeed = iocb.sg_ospeed;
327 		}
328 		tp->t_erase = iocb.sg_erase;
329 		tp->t_kill = iocb.sg_kill;
330 		tp->t_flags = iocb.sg_flags;
331 		(void) spl0();
332 		break;
333 
334 	/*
335 	 * Send current parameters to user
336 	 */
337 	case TIOCGETP:
338 		iocb.sg_ispeed = tp->t_ispeed;
339 		iocb.sg_ospeed = tp->t_ospeed;
340 		iocb.sg_erase = tp->t_erase;
341 		iocb.sg_kill = tp->t_kill;
342 		iocb.sg_flags = tp->t_flags;
343 		if (copyout((caddr_t)&iocb, addr, sizeof(iocb)))
344 			u.u_error = EFAULT;
345 		break;
346 
347 	/*
348 	 * Hang up line on last close
349 	 */
350 	case TIOCHPCL:
351 		tp->t_state |= HUPCLS;
352 		break;
353 
354 	case TIOCFLUSH:
355 		flushtty(tp, FREAD|FWRITE);
356 		break;
357 
358 	/*
359 	 * Ioctl entries to line discipline
360 	 */
361 	case DIOCSETP:
362 	case DIOCGETP:
363 		if ((*linesw[tp->t_line].l_ioctl)(com, tp, addr))
364 			u.u_error = ENOTTY;
365 		break;
366 
367 	/*
368 	 * Set and fetch special characters
369 	 */
370 	case TIOCSETC:
371 		if (copyin(addr, (caddr_t)&tun, sizeof(struct tchars)))
372 			u.u_error = EFAULT;
373 		break;
374 
375 	case TIOCGETC:
376 		if (copyout((caddr_t)&tun, addr, sizeof(struct tchars)))
377 			u.u_error = EFAULT;
378 		break;
379 
380 /* local ioctls */
381 	/*
382 	 * Set/get local special characters.
383 	 */
384 	case TIOCSLTC:
385 		if (copyin(addr, (caddr_t)&tlun, sizeof (struct ltchars)))
386 			u.u_error = EFAULT;
387 		break;
388 
389 	case TIOCGLTC:
390 		if (copyout((caddr_t)&tlun, addr, sizeof (struct ltchars)))
391 			u.u_error = EFAULT;
392 		break;
393 
394 	/*
395 	 * Return number of characters immediately available.
396 	 */
397 	case FIONREAD: {
398 		off_t nread;
399 
400 		switch (tp->t_line) {
401 
402 		case NETLDISC:
403 			nread = tp->t_rec ? tp->t_inbuf : 0;
404 			break;
405 
406 		case 0:
407 			(void) spl5();
408 			while (canon(tp)>=0)
409 				;
410 			(void) spl0();
411 			/* fall into ... */
412 
413 		case NTTYDISC:
414 			nread = tp->t_canq.c_cc;
415 			if (tp->t_flags & (RAW|CBREAK))
416 				nread += tp->t_rawq.c_cc;
417 			break;
418 
419 		}
420 		if (copyout((caddr_t)&nread, addr, sizeof (off_t)))
421 			u.u_error = EFAULT;
422 		break;
423 		}
424 
425 	/*
426 	 * Should allow SPGRP and GPGRP only if tty open for reading.
427 	 */
428 	case TIOCSPGRP:
429 		if (copyin(addr, (caddr_t)&tp->t_pgrp, sizeof (tp->t_pgrp)))
430 			u.u_error = EFAULT;
431 		break;
432 
433 	case TIOCGPGRP:
434 		if (copyout((caddr_t)&tp->t_pgrp, addr, sizeof(tp->t_pgrp)))
435 			u.u_error = EFAULT;
436 		break;
437 
438 	/*
439 	 * Modify local mode word.
440 	 */
441 	case TIOCLBIS:
442 		if (copyin(addr, (caddr_t)&temp, sizeof (tp->t_local)))
443 			u.u_error = EFAULT;
444 		else
445 			tp->t_local |= temp;
446 		break;
447 
448 	case TIOCLBIC:
449 		if (copyin(addr, (caddr_t)&temp, sizeof (tp->t_local)))
450 			u.u_error = EFAULT;
451 		else
452 			tp->t_local &= ~temp;
453 		break;
454 
455 	case TIOCLSET:
456 		if (copyin(addr, (caddr_t)&temp, sizeof (tp->t_local)))
457 			u.u_error = EFAULT;
458 		else
459 			tp->t_local = temp;
460 		break;
461 
462 	case TIOCLGET:
463 		if (copyout((caddr_t)&tp->t_local, addr, sizeof(tp->t_local)))
464 			u.u_error = EFAULT;
465 		break;
466 
467 	/*
468 	 * Return number of characters in
469 	 * the output.
470 	 */
471 	case TIOCOUTQ:
472 		if (copyout((caddr_t)&tp->t_outq.c_cc, addr, sizeof(tp->t_outq.c_cc)))
473 			u.u_error = EFAULT;
474 		break;
475 
476 	/*
477 	 * Simulate typing of a character at the terminal.
478 	 */
479 	case TIOCSTI:
480 		c = fubyte(addr);
481 		if (u.u_uid && u.u_ttyp != tp || c < 0)
482 			u.u_error = EFAULT;
483 		else
484 			(*linesw[tp->t_line].l_rint)(c, tp);
485 		break;
486 /* end of locals */
487 
488 	default:
489 		return(0);
490 	}
491 	return(1);
492 }
493