xref: /freebsd/libexec/getty/subr.c (revision ce834215a70ff69e7e222827437116eee2f9ac6f)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*static char sccsid[] = "from: @(#)subr.c	8.1 (Berkeley) 6/4/93";*/
36 static char rcsid[] = "$Id: subr.c,v 1.9 1997/02/22 14:21:40 peter Exp $";
37 #endif /* not lint */
38 
39 /*
40  * Melbourne getty.
41  */
42 #define COMPAT_43
43 #include <stdlib.h>
44 #include <unistd.h>
45 #include <string.h>
46 #include <termios.h>
47 #include <sys/ioctl.h>
48 #include <sys/param.h>
49 #include <syslog.h>
50 #ifdef DEBUG
51 #include <stdio.h>
52 #endif
53 
54 #include "gettytab.h"
55 #include "pathnames.h"
56 #include "extern.h"
57 
58 
59 #ifdef COMPAT_43
60 static void	compatflags __P((long));
61 #endif
62 
63 /*
64  * Get a table entry.
65  */
66 void
67 gettable(name, buf)
68 	const char *name;
69 	char *buf;
70 {
71 	register struct gettystrs *sp;
72 	register struct gettynums *np;
73 	register struct gettyflags *fp;
74 	long n;
75 	int l;
76 	char *p;
77 	char *msg = NULL;
78 	const char *dba[2];
79 
80 	static int firsttime = 1;
81 
82 	dba[0] = _PATH_GETTYTAB;
83 	dba[1] = 0;
84 
85 	if (firsttime) {
86 		/*
87 		 * we need to strdup() anything in the strings array
88 		 * initially in order to simplify things later
89 		 */
90 		for (sp = gettystrs; sp->field; sp++)
91 			if (sp->value != NULL) {
92 				/* handle these ones more carefully */
93 				if (sp >= &gettystrs[4] && sp <= &gettystrs[6])
94 					l = 2;
95 				else
96 					l = strlen(sp->value) + 1;
97 				if ((p = malloc(l)) != NULL) {
98 					strncpy(p, sp->value, l);
99 					p[l-1] = '\0';
100 				}
101 				/*
102 				 * replace, even if NULL, else we'll
103 				 * have problems with free()ing static mem
104 				 */
105 				sp->value = p;
106 			}
107 		firsttime = 0;
108 	}
109 
110 	switch (cgetent(&buf, (char **)dba, (char *)name)) {
111 	case 1:
112 		msg = "%s: couldn't resolve 'tc=' in gettytab '%s'";
113 	case 0:
114 		break;
115 	case -1:
116 		msg = "%s: unknown gettytab entry '%s'";
117 		break;
118 	case -2:
119 		msg = "%s: retrieving gettytab entry '%s': %m";
120 		break;
121 	case -3:
122 		msg = "%s: recursive 'tc=' reference gettytab entry '%s'";
123 		break;
124 	default:
125 		msg = "%s: unexpected cgetent() error for entry '%s'";
126 		break;
127 	}
128 
129 	if (msg != NULL) {
130 		syslog(LOG_ERR, msg, "getty", name);
131 		return;
132 	}
133 
134 	for (sp = gettystrs; sp->field; sp++) {
135 		if ((l = cgetstr(buf, (char*)sp->field, &p)) >= 0) {
136 			if (sp->value) {
137 				/* prefer existing value */
138 				if (strcmp(p, sp->value) != 0)
139 					free(sp->value);
140 				else {
141 					free(p);
142 					p = sp->value;
143 				}
144 			}
145 			sp->value = p;
146 		} else if (l == -1) {
147 			free(sp->value);
148 			sp->value = NULL;
149 		}
150 	}
151 
152 	for (np = gettynums; np->field; np++) {
153 		if (cgetnum(buf, (char*)np->field, &n) == -1)
154 			np->set = 0;
155 		else {
156 			np->set = 1;
157 			np->value = n;
158 		}
159 	}
160 
161 	for (fp = gettyflags; fp->field; fp++) {
162 		if (cgetcap(buf, (char *)fp->field, ':') == NULL)
163 			fp->set = 0;
164 		else {
165 			fp->set = 1;
166 			fp->value = 1 ^ fp->invrt;
167 		}
168 	}
169 
170 #ifdef DEBUG
171 	printf("name=\"%s\", buf=\"%s\"\r\n", name, buf);
172 	for (sp = gettystrs; sp->field; sp++)
173 		printf("cgetstr: %s=%s\r\n", sp->field, sp->value);
174 	for (np = gettynums; np->field; np++)
175 		printf("cgetnum: %s=%d\r\n", np->field, np->value);
176 	for (fp = gettyflags; fp->field; fp++)
177 		printf("cgetflags: %s='%c' set='%c'\r\n", fp->field,
178 		       fp->value + '0', fp->set + '0');
179 #endif /* DEBUG */
180 }
181 
182 void
183 gendefaults()
184 {
185 	register struct gettystrs *sp;
186 	register struct gettynums *np;
187 	register struct gettyflags *fp;
188 
189 	for (sp = gettystrs; sp->field; sp++)
190 		if (sp->value)
191 			sp->defalt = strdup(sp->value);
192 	for (np = gettynums; np->field; np++)
193 		if (np->set)
194 			np->defalt = np->value;
195 	for (fp = gettyflags; fp->field; fp++)
196 		if (fp->set)
197 			fp->defalt = fp->value;
198 		else
199 			fp->defalt = fp->invrt;
200 }
201 
202 void
203 setdefaults()
204 {
205 	register struct gettystrs *sp;
206 	register struct gettynums *np;
207 	register struct gettyflags *fp;
208 
209 	for (sp = gettystrs; sp->field; sp++)
210 		if (!sp->value)
211 			sp->value = !sp->defalt ? sp->defalt
212 						: strdup(sp->defalt);
213 	for (np = gettynums; np->field; np++)
214 		if (!np->set)
215 			np->value = np->defalt;
216 	for (fp = gettyflags; fp->field; fp++)
217 		if (!fp->set)
218 			fp->value = fp->defalt;
219 }
220 
221 static char **
222 charnames[] = {
223 	&ER, &KL, &IN, &QU, &XN, &XF, &ET, &BK,
224 	&SU, &DS, &RP, &FL, &WE, &LN, 0
225 };
226 
227 static char *
228 charvars[] = {
229 	&tmode.c_cc[VERASE], &tmode.c_cc[VKILL], &tmode.c_cc[VINTR],
230 	&tmode.c_cc[VQUIT], &tmode.c_cc[VSTART], &tmode.c_cc[VSTOP],
231 	&tmode.c_cc[VEOF], &tmode.c_cc[VEOL], &tmode.c_cc[VSUSP],
232 	&tmode.c_cc[VDSUSP], &tmode.c_cc[VREPRINT], &tmode.c_cc[VDISCARD],
233 	&tmode.c_cc[VWERASE], &tmode.c_cc[VLNEXT], 0
234 };
235 
236 void
237 setchars()
238 {
239 	register int i;
240 	register const char *p;
241 
242 	for (i = 0; charnames[i]; i++) {
243 		p = *charnames[i];
244 		if (p && *p)
245 			*charvars[i] = *p;
246 		else
247 			*charvars[i] = _POSIX_VDISABLE;
248 	}
249 }
250 
251 /* Macros to clear/set/test flags. */
252 #define	SET(t, f)	(t) |= (f)
253 #define	CLR(t, f)	(t) &= ~(f)
254 #define	ISSET(t, f)	((t) & (f))
255 
256 void
257 setflags(n)
258 	int n;
259 {
260 	register tcflag_t iflag, oflag, cflag, lflag;
261 
262 #ifdef COMPAT_43
263 	switch (n) {
264 	case 0:
265 		if (F0set) {
266 			compatflags(F0);
267 			return;
268 		}
269 		break;
270 	case 1:
271 		if (F1set) {
272 			compatflags(F1);
273 			return;
274 		}
275 		break;
276 	default:
277 		if (F2set) {
278 			compatflags(F2);
279 			return;
280 		}
281 		break;
282 	}
283 #endif
284 
285 	switch (n) {
286 	case 0:
287 		if (C0set && I0set && L0set && O0set) {
288 			tmode.c_cflag = C0;
289 			tmode.c_iflag = I0;
290 			tmode.c_lflag = L0;
291 			tmode.c_oflag = O0;
292 			return;
293 		}
294 		break;
295 	case 1:
296 		if (C1set && I1set && L1set && O1set) {
297 			tmode.c_cflag = C1;
298 			tmode.c_iflag = I1;
299 			tmode.c_lflag = L1;
300 			tmode.c_oflag = O1;
301 			return;
302 		}
303 		break;
304 	default:
305 		if (C2set && I2set && L2set && O2set) {
306 			tmode.c_cflag = C2;
307 			tmode.c_iflag = I2;
308 			tmode.c_lflag = L2;
309 			tmode.c_oflag = O2;
310 			return;
311 		}
312 		break;
313 	}
314 
315 	iflag = omode.c_iflag;
316 	oflag = omode.c_oflag;
317 	cflag = omode.c_cflag;
318 	lflag = omode.c_lflag;
319 
320 	if (NP) {
321 		CLR(cflag, CSIZE|PARENB);
322 		SET(cflag, CS8);
323 		CLR(iflag, ISTRIP|INPCK|IGNPAR);
324 	} else if (AP || EP || OP) {
325 		CLR(cflag, CSIZE);
326 		SET(cflag, CS7|PARENB);
327 		SET(iflag, ISTRIP);
328 		if (OP && !EP) {
329 			SET(iflag, INPCK|IGNPAR);
330 			SET(cflag, PARODD);
331 			if (AP)
332 				CLR(iflag, INPCK);
333 		} else if (EP && !OP) {
334 			SET(iflag, INPCK|IGNPAR);
335 			CLR(cflag, PARODD);
336 			if (AP)
337 				CLR(iflag, INPCK);
338 		} else if (AP || (EP && OP)) {
339 			CLR(iflag, INPCK|IGNPAR);
340 			CLR(cflag, PARODD);
341 		}
342 	} /* else, leave as is */
343 
344 #if 0
345 	if (UC)
346 		f |= LCASE;
347 #endif
348 
349 	if (HC)
350 		SET(cflag, HUPCL);
351 	else
352 		CLR(cflag, HUPCL);
353 
354 	if (MB)
355 		SET(cflag, MDMBUF);
356 	else
357 		CLR(cflag, MDMBUF);
358 
359 	if (HW)
360 		SET(cflag, CRTSCTS);
361 	else
362 		CLR(cflag, CRTSCTS);
363 
364 	if (NL) {
365 		SET(iflag, ICRNL);
366 		SET(oflag, ONLCR|OPOST);
367 	} else {
368 		CLR(iflag, ICRNL);
369 		CLR(oflag, ONLCR);
370 	}
371 
372 	if (!HT)
373 		SET(oflag, OXTABS|OPOST);
374 	else
375 		CLR(oflag, OXTABS);
376 
377 #ifdef XXX_DELAY
378 	SET(f, delaybits());
379 #endif
380 
381 	if (n == 1) {		/* read mode flags */
382 		if (RW) {
383 			iflag = 0;
384 			CLR(oflag, OPOST);
385 			CLR(cflag, CSIZE|PARENB);
386 			SET(cflag, CS8);
387 			lflag = 0;
388 		} else {
389 			CLR(lflag, ICANON);
390 		}
391 		goto out;
392 	}
393 
394 	if (n == 0)
395 		goto out;
396 
397 #if 0
398 	if (CB)
399 		SET(f, CRTBS);
400 #endif
401 
402 	if (CE)
403 		SET(lflag, ECHOE);
404 	else
405 		CLR(lflag, ECHOE);
406 
407 	if (CK)
408 		SET(lflag, ECHOKE);
409 	else
410 		CLR(lflag, ECHOKE);
411 
412 	if (PE)
413 		SET(lflag, ECHOPRT);
414 	else
415 		CLR(lflag, ECHOPRT);
416 
417 	if (EC)
418 		SET(lflag, ECHO);
419 	else
420 		CLR(lflag, ECHO);
421 
422 	if (XC)
423 		SET(lflag, ECHOCTL);
424 	else
425 		CLR(lflag, ECHOCTL);
426 
427 	if (DX)
428 		SET(lflag, IXANY);
429 	else
430 		CLR(lflag, IXANY);
431 
432 out:
433 	tmode.c_iflag = iflag;
434 	tmode.c_oflag = oflag;
435 	tmode.c_cflag = cflag;
436 	tmode.c_lflag = lflag;
437 }
438 
439 #ifdef COMPAT_43
440 /*
441  * Old TTY => termios, snatched from <sys/kern/tty_compat.c>
442  */
443 void
444 compatflags(flags)
445 register long flags;
446 {
447 	register tcflag_t iflag, oflag, cflag, lflag;
448 
449 	iflag = BRKINT|ICRNL|IMAXBEL|IXON|IXANY;
450 	oflag = OPOST|ONLCR|OXTABS;
451 	cflag = CREAD;
452 	lflag = ICANON|ISIG|IEXTEN;
453 
454 	if (ISSET(flags, TANDEM))
455 		SET(iflag, IXOFF);
456 	else
457 		CLR(iflag, IXOFF);
458 	if (ISSET(flags, ECHO))
459 		SET(lflag, ECHO);
460 	else
461 		CLR(lflag, ECHO);
462 	if (ISSET(flags, CRMOD)) {
463 		SET(iflag, ICRNL);
464 		SET(oflag, ONLCR);
465 	} else {
466 		CLR(iflag, ICRNL);
467 		CLR(oflag, ONLCR);
468 	}
469 	if (ISSET(flags, XTABS))
470 		SET(oflag, OXTABS);
471 	else
472 		CLR(oflag, OXTABS);
473 
474 
475 	if (ISSET(flags, RAW)) {
476 		iflag &= IXOFF;
477 		CLR(lflag, ISIG|ICANON|IEXTEN);
478 		CLR(cflag, PARENB);
479 	} else {
480 		SET(iflag, BRKINT|IXON|IMAXBEL);
481 		SET(lflag, ISIG|IEXTEN);
482 		if (ISSET(flags, CBREAK))
483 			CLR(lflag, ICANON);
484 		else
485 			SET(lflag, ICANON);
486 		switch (ISSET(flags, ANYP)) {
487 		case 0:
488 			CLR(cflag, PARENB);
489 			break;
490 		case ANYP:
491 			SET(cflag, PARENB);
492 			CLR(iflag, INPCK);
493 			break;
494 		case EVENP:
495 			SET(cflag, PARENB);
496 			SET(iflag, INPCK);
497 			CLR(cflag, PARODD);
498 			break;
499 		case ODDP:
500 			SET(cflag, PARENB);
501 			SET(iflag, INPCK);
502 			SET(cflag, PARODD);
503 			break;
504 		}
505 	}
506 
507 	/* Nothing we can do with CRTBS. */
508 	if (ISSET(flags, PRTERA))
509 		SET(lflag, ECHOPRT);
510 	else
511 		CLR(lflag, ECHOPRT);
512 	if (ISSET(flags, CRTERA))
513 		SET(lflag, ECHOE);
514 	else
515 		CLR(lflag, ECHOE);
516 	/* Nothing we can do with TILDE. */
517 	if (ISSET(flags, MDMBUF))
518 		SET(cflag, MDMBUF);
519 	else
520 		CLR(cflag, MDMBUF);
521 	if (ISSET(flags, NOHANG))
522 		CLR(cflag, HUPCL);
523 	else
524 		SET(cflag, HUPCL);
525 	if (ISSET(flags, CRTKIL))
526 		SET(lflag, ECHOKE);
527 	else
528 		CLR(lflag, ECHOKE);
529 	if (ISSET(flags, CTLECH))
530 		SET(lflag, ECHOCTL);
531 	else
532 		CLR(lflag, ECHOCTL);
533 	if (!ISSET(flags, DECCTQ))
534 		SET(iflag, IXANY);
535 	else
536 		CLR(iflag, IXANY);
537 	CLR(lflag, TOSTOP|FLUSHO|PENDIN|NOFLSH);
538 	SET(lflag, ISSET(flags, TOSTOP|FLUSHO|PENDIN|NOFLSH));
539 
540 	if (ISSET(flags, RAW|LITOUT|PASS8)) {
541 		CLR(cflag, CSIZE);
542 		SET(cflag, CS8);
543 		if (!ISSET(flags, RAW|PASS8))
544 			SET(iflag, ISTRIP);
545 		else
546 			CLR(iflag, ISTRIP);
547 		if (!ISSET(flags, RAW|LITOUT))
548 			SET(oflag, OPOST);
549 		else
550 			CLR(oflag, OPOST);
551 	} else {
552 		CLR(cflag, CSIZE);
553 		SET(cflag, CS7);
554 		SET(iflag, ISTRIP);
555 		SET(oflag, OPOST);
556 	}
557 
558 	tmode.c_iflag = iflag;
559 	tmode.c_oflag = oflag;
560 	tmode.c_cflag = cflag;
561 	tmode.c_lflag = lflag;
562 }
563 #endif
564 
565 #ifdef XXX_DELAY
566 struct delayval {
567 	unsigned	delay;		/* delay in ms */
568 	int		bits;
569 };
570 
571 /*
572  * below are random guesses, I can't be bothered checking
573  */
574 
575 struct delayval	crdelay[] = {
576 	{ 1,		CR1 },
577 	{ 2,		CR2 },
578 	{ 3,		CR3 },
579 	{ 83,		CR1 },
580 	{ 166,		CR2 },
581 	{ 0,		CR3 },
582 };
583 
584 struct delayval nldelay[] = {
585 	{ 1,		NL1 },		/* special, calculated */
586 	{ 2,		NL2 },
587 	{ 3,		NL3 },
588 	{ 100,		NL2 },
589 	{ 0,		NL3 },
590 };
591 
592 struct delayval	bsdelay[] = {
593 	{ 1,		BS1 },
594 	{ 0,		0 },
595 };
596 
597 struct delayval	ffdelay[] = {
598 	{ 1,		FF1 },
599 	{ 1750,		FF1 },
600 	{ 0,		FF1 },
601 };
602 
603 struct delayval	tbdelay[] = {
604 	{ 1,		TAB1 },
605 	{ 2,		TAB2 },
606 	{ 3,		XTABS },	/* this is expand tabs */
607 	{ 100,		TAB1 },
608 	{ 0,		TAB2 },
609 };
610 
611 int
612 delaybits()
613 {
614 	register int f;
615 
616 	f  = adelay(CD, crdelay);
617 	f |= adelay(ND, nldelay);
618 	f |= adelay(FD, ffdelay);
619 	f |= adelay(TD, tbdelay);
620 	f |= adelay(BD, bsdelay);
621 	return (f);
622 }
623 
624 int
625 adelay(ms, dp)
626 	register ms;
627 	register struct delayval *dp;
628 {
629 	if (ms == 0)
630 		return (0);
631 	while (dp->delay && ms > dp->delay)
632 		dp++;
633 	return (dp->bits);
634 }
635 #endif
636 
637 char	editedhost[MAXHOSTNAMELEN];
638 
639 void
640 edithost(pat)
641 	register const char *pat;
642 {
643 	register const char *host = HN;
644 	register char *res = editedhost;
645 
646 	if (!pat)
647 		pat = "";
648 	while (*pat) {
649 		switch (*pat) {
650 
651 		case '#':
652 			if (*host)
653 				host++;
654 			break;
655 
656 		case '@':
657 			if (*host)
658 				*res++ = *host++;
659 			break;
660 
661 		default:
662 			*res++ = *pat;
663 			break;
664 
665 		}
666 		if (res == &editedhost[sizeof editedhost - 1]) {
667 			*res = '\0';
668 			return;
669 		}
670 		pat++;
671 	}
672 	if (*host)
673 		strncpy(res, host, sizeof editedhost - (res - editedhost) - 1);
674 	else
675 		*res = '\0';
676 	editedhost[sizeof editedhost - 1] = '\0';
677 }
678 
679 static struct speedtab {
680 	int	speed;
681 	int	uxname;
682 } speedtab[] = {
683 	{ 50,	B50 },
684 	{ 75,	B75 },
685 	{ 110,	B110 },
686 	{ 134,	B134 },
687 	{ 150,	B150 },
688 	{ 200,	B200 },
689 	{ 300,	B300 },
690 	{ 600,	B600 },
691 	{ 1200,	B1200 },
692 	{ 1800,	B1800 },
693 	{ 2400,	B2400 },
694 	{ 4800,	B4800 },
695 	{ 9600,	B9600 },
696 	{ 19200, EXTA },
697 	{ 19,	EXTA },		/* for people who say 19.2K */
698 	{ 38400, EXTB },
699 	{ 38,	EXTB },
700 	{ 7200,	EXTB },		/* alternative */
701 	{ 57600, B57600 },
702 	{ 115200, B115200 },
703 	{ 0 }
704 };
705 
706 int
707 speed(val)
708 	int val;
709 {
710 	register struct speedtab *sp;
711 
712 	if (val <= B115200)
713 		return (val);
714 
715 	for (sp = speedtab; sp->speed; sp++)
716 		if (sp->speed == val)
717 			return (sp->uxname);
718 
719 	return (B300);		/* default in impossible cases */
720 }
721 
722 void
723 makeenv(env)
724 	char *env[];
725 {
726 	static char termbuf[128] = "TERM=";
727 	register char *p, *q;
728 	register char **ep;
729 
730 	ep = env;
731 	if (TT && *TT) {
732 		strcat(termbuf, TT);
733 		*ep++ = termbuf;
734 	}
735 	if ((p = EV)) {
736 		q = p;
737 		while ((q = strchr(q, ','))) {
738 			*q++ = '\0';
739 			*ep++ = p;
740 			p = q;
741 		}
742 		if (*p)
743 			*ep++ = p;
744 	}
745 	*ep = (char *)0;
746 }
747 
748 /*
749  * This speed select mechanism is written for the Develcon DATASWITCH.
750  * The Develcon sends a string of the form "B{speed}\n" at a predefined
751  * baud rate. This string indicates the user's actual speed.
752  * The routine below returns the terminal type mapped from derived speed.
753  */
754 struct	portselect {
755 	const char	*ps_baud;
756 	const char	*ps_type;
757 } portspeeds[] = {
758 	{ "B110",	"std.110" },
759 	{ "B134",	"std.134" },
760 	{ "B150",	"std.150" },
761 	{ "B300",	"std.300" },
762 	{ "B600",	"std.600" },
763 	{ "B1200",	"std.1200" },
764 	{ "B2400",	"std.2400" },
765 	{ "B4800",	"std.4800" },
766 	{ "B9600",	"std.9600" },
767 	{ "B19200",	"std.19200" },
768 	{ 0 }
769 };
770 
771 const char *
772 portselector()
773 {
774 	char c, baud[20];
775 	const char *type = "default";
776 	register struct portselect *ps;
777 	int len;
778 
779 	alarm(5*60);
780 	for (len = 0; len < sizeof (baud) - 1; len++) {
781 		if (read(STDIN_FILENO, &c, 1) <= 0)
782 			break;
783 		c &= 0177;
784 		if (c == '\n' || c == '\r')
785 			break;
786 		if (c == 'B')
787 			len = 0;	/* in case of leading garbage */
788 		baud[len] = c;
789 	}
790 	baud[len] = '\0';
791 	for (ps = portspeeds; ps->ps_baud; ps++)
792 		if (strcmp(ps->ps_baud, baud) == 0) {
793 			type = ps->ps_type;
794 			break;
795 		}
796 	sleep(2);	/* wait for connection to complete */
797 	return (type);
798 }
799 
800 /*
801  * This auto-baud speed select mechanism is written for the Micom 600
802  * portselector. Selection is done by looking at how the character '\r'
803  * is garbled at the different speeds.
804  */
805 #include <sys/time.h>
806 
807 const char *
808 autobaud()
809 {
810 	int rfds;
811 	struct timeval timeout;
812 	char c;
813 	const char *type = "9600-baud";
814 
815 	(void)tcflush(0, TCIOFLUSH);
816 	rfds = 1 << 0;
817 	timeout.tv_sec = 5;
818 	timeout.tv_usec = 0;
819 	if (select(32, (fd_set *)&rfds, (fd_set *)NULL,
820 	    (fd_set *)NULL, &timeout) <= 0)
821 		return (type);
822 	if (read(STDIN_FILENO, &c, sizeof(char)) != sizeof(char))
823 		return (type);
824 	timeout.tv_sec = 0;
825 	timeout.tv_usec = 20;
826 	(void) select(32, (fd_set *)NULL, (fd_set *)NULL,
827 	    (fd_set *)NULL, &timeout);
828 	(void)tcflush(0, TCIOFLUSH);
829 	switch (c & 0377) {
830 
831 	case 0200:		/* 300-baud */
832 		type = "300-baud";
833 		break;
834 
835 	case 0346:		/* 1200-baud */
836 		type = "1200-baud";
837 		break;
838 
839 	case  015:		/* 2400-baud */
840 	case 0215:
841 		type = "2400-baud";
842 		break;
843 
844 	default:		/* 4800-baud */
845 		type = "4800-baud";
846 		break;
847 
848 	case 0377:		/* 9600-baud */
849 		type = "9600-baud";
850 		break;
851 	}
852 	return (type);
853 }
854