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input.c revision 1.13
      1 /*	$NetBSD: input.c,v 1.13 1999/07/25 00:24:38 hubertf Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1990, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Ed James.
      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 
     39 /*
     40  * Copyright (c) 1987 by Ed James, UC Berkeley.  All rights reserved.
     41  *
     42  * Copy permission is hereby granted provided that this notice is
     43  * retained on all partial or complete copies.
     44  *
     45  * For more info on this and all of my stuff, mail edjames (at) berkeley.edu.
     46  */
     47 
     48 #include <sys/cdefs.h>
     49 #ifndef lint
     50 #if 0
     51 static char sccsid[] = "@(#)input.c	8.1 (Berkeley) 5/31/93";
     52 #else
     53 __RCSID("$NetBSD: input.c,v 1.13 1999/07/25 00:24:38 hubertf Exp $");
     54 #endif
     55 #endif not lint
     56 
     57 #include "include.h"
     58 #include "pathnames.h"
     59 
     60 #define MAXRULES	6
     61 #define MAXDEPTH	15
     62 
     63 #define RETTOKEN	'\n'
     64 #define REDRAWTOKEN	'\014'	/* CTRL(L) */
     65 #define	SHELLTOKEN	'!'
     66 #define HELPTOKEN	'?'
     67 #define ALPHATOKEN	256
     68 #define NUMTOKEN	257
     69 
     70 typedef struct {
     71 	int	token;
     72 	int	to_state;
     73 	const char	*str;
     74 	const char	*(*func) __P((char));
     75 } RULE;
     76 
     77 typedef struct {
     78 	int	num_rules;
     79 	RULE	*rule;
     80 } STATE;
     81 
     82 typedef struct {
     83 	char	str[20];
     84 	int	state;
     85 	int	rule;
     86 	int	ch;
     87 	int	pos;
     88 } STACK;
     89 
     90 #define T_RULE		stack[level].rule
     91 #define T_STATE		stack[level].state
     92 #define T_STR		stack[level].str
     93 #define T_POS		stack[level].pos
     94 #define	T_CH		stack[level].ch
     95 
     96 #define NUMELS(a)	(sizeof (a) / sizeof (*(a)))
     97 
     98 #define NUMSTATES	NUMELS(st)
     99 
    100 
    101 RULE	state0[] = {	{ ALPHATOKEN,	1,	"%c:",		setplane},
    102 			{ RETTOKEN,	-1,	"",		NULL	},
    103 			{ HELPTOKEN,	12,	" [a-z]<ret>",	NULL	}},
    104 	state1[] = {	{ 't',		2,	" turn",	turn	},
    105 			{ 'a',		3,	" altitude:",	NULL	},
    106 			{ 'c',		4,	" circle",	circle	},
    107 			{ 'm',		7,	" mark",	mark	},
    108 			{ 'u',		7,	" unmark",	unmark	},
    109 			{ 'i',		7,	" ignore",	ignore	},
    110 			{ HELPTOKEN,	12,	" tacmui",	NULL	}},
    111 	state2[] = {	{ 'l',		6,	" left",	left	},
    112 			{ 'r',		6,	" right",	right	},
    113 			{ 'L',		4,	" left 90",	Left	},
    114 			{ 'R',		4,	" right 90",	Right	},
    115 			{ 't',		11,	" towards",	NULL	},
    116 			{ 'w',		4,	" to 0",	to_dir	},
    117 			{ 'e',		4,	" to 45",	to_dir	},
    118 			{ 'd',		4,	" to 90",	to_dir	},
    119 			{ 'c',		4,	" to 135",	to_dir	},
    120 			{ 'x',		4,	" to 180",	to_dir	},
    121 			{ 'z',		4,	" to 225",	to_dir	},
    122 			{ 'a',		4,	" to 270",	to_dir	},
    123 			{ 'q',		4,	" to 315",	to_dir	},
    124 			{ HELPTOKEN,	12,	" lrLRt<dir>",	NULL	}},
    125 	state3[] = {	{ '+',		10,	" climb",	climb	},
    126 			{ 'c',		10,	" climb",	climb	},
    127 			{ '-',		10,	" descend",	descend	},
    128 			{ 'd',		10,	" descend",	descend	},
    129 			{ NUMTOKEN,	7,	" %c000 feet",	setalt	},
    130 			{ HELPTOKEN,	12,	" +-cd[0-9]",	NULL	}},
    131 	state4[] = {	{ '@',		9,	" at",		NULL	},
    132 			{ 'a',		9,	" at",		NULL	},
    133 			{ RETTOKEN,	-1,	"",		NULL	},
    134 			{ HELPTOKEN,	12,	" @a<ret>",	NULL	}},
    135 	state5[] = {	{ NUMTOKEN,	7,	"%c",		delayb	},
    136 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    137 	state6[] = {	{ '@',		9,	" at",		NULL	},
    138 			{ 'a',		9,	" at",		NULL	},
    139 			{ 'w',		4,	" 0",		rel_dir	},
    140 			{ 'e',		4,	" 45",		rel_dir	},
    141 			{ 'd',		4,	" 90",		rel_dir	},
    142 			{ 'c',		4,	" 135",		rel_dir	},
    143 			{ 'x',		4,	" 180",		rel_dir	},
    144 			{ 'z',		4,	" 225",		rel_dir	},
    145 			{ 'a',		4,	" 270",		rel_dir	},
    146 			{ 'q',		4,	" 315",		rel_dir	},
    147 			{ RETTOKEN,	-1,	"",		NULL	},
    148 			{ HELPTOKEN,	12,	" @a<dir><ret>",NULL	}},
    149 	state7[] = {	{ RETTOKEN,	-1,	"",		NULL	},
    150 			{ HELPTOKEN,	12,	" <ret>",	NULL	}},
    151 	state8[] = {	{ NUMTOKEN,	4,	"%c",		benum	},
    152 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    153 	state9[] = {	{ 'b',		5,	" beacon #",	NULL	},
    154 			{ '*',		5,	" beacon #",	NULL	},
    155 			{ HELPTOKEN,	12,	" b*",		NULL	}},
    156 	state10[] = {	{ NUMTOKEN,	7,	" %c000 ft",	setrelalt},
    157 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    158 	state11[] = {	{ 'b',		8,	" beacon #",	beacon	},
    159 			{ '*',		8,	" beacon #",	beacon	},
    160 			{ 'e',		8,	" exit #",	ex_it	},
    161 			{ 'a',		8,	" airport #",	airport	},
    162 			{ HELPTOKEN,	12,	" b*ea",	NULL	}},
    163 	state12[] = {	{ -1,		-1,	"",		NULL	}};
    164 
    165 #define DEF_STATE(s)	{ NUMELS(s),	(s)	}
    166 
    167 STATE	st[] = {
    168 	DEF_STATE(state0), DEF_STATE(state1), DEF_STATE(state2),
    169 	DEF_STATE(state3), DEF_STATE(state4), DEF_STATE(state5),
    170 	DEF_STATE(state6), DEF_STATE(state7), DEF_STATE(state8),
    171 	DEF_STATE(state9), DEF_STATE(state10), DEF_STATE(state11),
    172 	DEF_STATE(state12)
    173 };
    174 
    175 PLANE	p;
    176 STACK	stack[MAXDEPTH];
    177 int	level;
    178 int	tval;
    179 int	dest_type, dest_no, dir;
    180 
    181 int
    182 pop()
    183 {
    184 	if (level == 0)
    185 		return (-1);
    186 	level--;
    187 
    188 	ioclrtoeol(T_POS);
    189 
    190 	strcpy(T_STR, "");
    191 	T_RULE = -1;
    192 	T_CH = -1;
    193 	return (0);
    194 }
    195 
    196 void
    197 rezero()
    198 {
    199 	iomove(0);
    200 
    201 	level = 0;
    202 	T_STATE = 0;
    203 	T_RULE = -1;
    204 	T_CH = -1;
    205 	T_POS = 0;
    206 	strcpy(T_STR, "");
    207 }
    208 
    209 void
    210 push(ruleno, ch)
    211 	int ruleno, ch;
    212 {
    213 	int	newstate, newpos;
    214 
    215 	(void)sprintf(T_STR, st[T_STATE].rule[ruleno].str, tval);
    216 	T_RULE = ruleno;
    217 	T_CH = ch;
    218 	newstate = st[T_STATE].rule[ruleno].to_state;
    219 	newpos = T_POS + strlen(T_STR);
    220 
    221 	ioaddstr(T_POS, T_STR);
    222 
    223 	if (level == 0)
    224 		ioclrtobot();
    225 	level++;
    226 	T_STATE = newstate;
    227 	T_POS = newpos;
    228 	T_RULE = -1;
    229 	strcpy(T_STR, "");
    230 }
    231 
    232 int
    233 getcommand()
    234 {
    235 	int	c, i, done;
    236 	const char	*s, *(*func) __P((char));
    237 	PLANE	*pp;
    238 
    239 	rezero();
    240 
    241 	do {
    242 		c = gettoken();
    243 		if (c == tty_new.c_cc[VERASE]) {
    244 			if (pop() < 0)
    245 				noise();
    246 		} else if (c == tty_new.c_cc[VKILL]) {
    247 			while (pop() >= 0)
    248 				;
    249 		} else {
    250 			done = 0;
    251 			for (i = 0; i < st[T_STATE].num_rules; i++) {
    252 				if (st[T_STATE].rule[i].token == c ||
    253 				    st[T_STATE].rule[i].token == tval) {
    254 					push(i, (c >= ALPHATOKEN) ? tval : c);
    255 					done = 1;
    256 					break;
    257 				}
    258 			}
    259 			if (!done)
    260 				noise();
    261 		}
    262 	} while (T_STATE != -1);
    263 
    264 	if (level == 1)
    265 		return (1);	/* forced update */
    266 
    267 	dest_type = T_NODEST;
    268 
    269 	for (i = 0; i < level; i++) {
    270 		func = st[stack[i].state].rule[stack[i].rule].func;
    271 		if (func != NULL)
    272 			if ((s = (*func)(stack[i].ch)) != NULL) {
    273 				ioerror(stack[i].pos, strlen(stack[i].str), s);
    274 				return (-1);
    275 			}
    276 	}
    277 
    278 	pp = findplane(p.plane_no);
    279 	if (pp->new_altitude != p.new_altitude)
    280 		pp->new_altitude = p.new_altitude;
    281 	else if (pp->status != p.status)
    282 		pp->status = p.status;
    283 	else {
    284 		pp->new_dir = p.new_dir;
    285 		pp->delayd = p.delayd;
    286 		pp->delayd_no = p.delayd_no;
    287 	}
    288 	return (0);
    289 }
    290 
    291 void
    292 noise()
    293 {
    294 	putchar('\07');
    295 	fflush(stdout);
    296 }
    297 
    298 int
    299 gettoken()
    300 {
    301 	while ((tval = getAChar()) == REDRAWTOKEN || tval == SHELLTOKEN)
    302 	{
    303 		if (tval == SHELLTOKEN)
    304 		{
    305 #ifdef BSD
    306 			struct itimerval	itv;
    307 			itv.it_value.tv_sec = 0;
    308 			itv.it_value.tv_usec = 0;
    309 			setitimer(ITIMER_REAL, &itv, NULL);
    310 #endif
    311 #ifdef SYSV
    312 			int aval;
    313 			aval = alarm(0);
    314 #endif
    315 			if (fork() == 0)	/* child */
    316 			{
    317 				char *shell, *base;
    318 
    319 				done_screen();
    320 
    321 						 /* run user's favorite shell */
    322 				if ((shell = getenv("SHELL")) != NULL)
    323 				{
    324 					base = strrchr(shell, '/');
    325 					if (base == NULL)
    326 						base = shell;
    327 					else
    328 						base++;
    329 					execl(shell, base, 0);
    330 				}
    331 				else
    332 					execl(_PATH_BSHELL, "sh", 0);
    333 
    334 				exit(0);	/* oops */
    335 			}
    336 
    337 			wait(0);
    338 			tcsetattr(fileno(stdin), TCSADRAIN, &tty_new);
    339 #ifdef BSD
    340 			itv.it_value.tv_sec = 0;
    341 			itv.it_value.tv_usec = 1;
    342 			itv.it_interval.tv_sec = sp->update_secs;
    343 			itv.it_interval.tv_usec = 0;
    344 			setitimer(ITIMER_REAL, &itv, NULL);
    345 #endif
    346 #ifdef SYSV
    347 			alarm(aval);
    348 #endif
    349 		}
    350 		redraw();
    351 	}
    352 
    353 	if (isdigit(tval))
    354 		return (NUMTOKEN);
    355 	else if (isalpha(tval))
    356 		return (ALPHATOKEN);
    357 	else
    358 		return (tval);
    359 }
    360 
    361 const char	*
    362 setplane(c)
    363 	char c;
    364 {
    365 	PLANE	*pp;
    366 
    367 	pp = findplane(number(c));
    368 	if (pp == NULL)
    369 		return ("Unknown Plane");
    370 	memcpy(&p, pp, sizeof (p));
    371 	p.delayd = 0;
    372 	return (NULL);
    373 }
    374 
    375 const char	*
    376 turn(c)
    377 	char c __attribute__((__unused__));
    378 {
    379 	if (p.altitude == 0)
    380 		return ("Planes at airports may not change direction");
    381 	return (NULL);
    382 }
    383 
    384 const char	*
    385 circle(c)
    386 	char c __attribute__((__unused__));
    387 {
    388 	if (p.altitude == 0)
    389 		return ("Planes cannot circle on the ground");
    390 	p.new_dir = MAXDIR;
    391 	return (NULL);
    392 }
    393 
    394 const char	*
    395 left(c)
    396 	char c __attribute__((__unused__));
    397 {
    398 	dir = D_LEFT;
    399 	p.new_dir = p.dir - 1;
    400 	if (p.new_dir < 0)
    401 		p.new_dir += MAXDIR;
    402 	return (NULL);
    403 }
    404 
    405 const char	*
    406 right(c)
    407 	char c __attribute__((__unused__));
    408 {
    409 	dir = D_RIGHT;
    410 	p.new_dir = p.dir + 1;
    411 	if (p.new_dir >= MAXDIR)
    412 		p.new_dir -= MAXDIR;
    413 	return (NULL);
    414 }
    415 
    416 const char	*
    417 Left(c)
    418 	char c __attribute__((__unused__));
    419 {
    420 	p.new_dir = p.dir - 2;
    421 	if (p.new_dir < 0)
    422 		p.new_dir += MAXDIR;
    423 	return (NULL);
    424 }
    425 
    426 const char	*
    427 Right(c)
    428 	char c __attribute__((__unused__));
    429 {
    430 	p.new_dir = p.dir + 2;
    431 	if (p.new_dir >= MAXDIR)
    432 		p.new_dir -= MAXDIR;
    433 	return (NULL);
    434 }
    435 
    436 const char	*
    437 delayb(c)
    438 	char c;
    439 {
    440 	int	xdiff, ydiff;
    441 
    442 	c -= '0';
    443 
    444 	if (c >= sp->num_beacons)
    445 		return ("Unknown beacon");
    446 	xdiff = sp->beacon[(int)c].x - p.xpos;
    447 	xdiff = SGN(xdiff);
    448 	ydiff = sp->beacon[(int)c].y - p.ypos;
    449 	ydiff = SGN(ydiff);
    450 	if (xdiff != displacement[p.dir].dx || ydiff != displacement[p.dir].dy)
    451 		return ("Beacon is not in flight path");
    452 	p.delayd = 1;
    453 	p.delayd_no = c;
    454 
    455 	if (dest_type != T_NODEST) {
    456 		switch (dest_type) {
    457 		case T_BEACON:
    458 			xdiff = sp->beacon[dest_no].x - sp->beacon[(int)c].x;
    459 			ydiff = sp->beacon[dest_no].y - sp->beacon[(int)c].y;
    460 			break;
    461 		case T_EXIT:
    462 			xdiff = sp->exit[dest_no].x - sp->beacon[(int)c].x;
    463 			ydiff = sp->exit[dest_no].y - sp->beacon[(int)c].y;
    464 			break;
    465 		case T_AIRPORT:
    466 			xdiff = sp->airport[dest_no].x - sp->beacon[(int)c].x;
    467 			ydiff = sp->airport[dest_no].y - sp->beacon[(int)c].y;
    468 			break;
    469 		default:
    470 			return ("Bad case in delayb!  Get help!");
    471 			break;
    472 		}
    473 		if (xdiff == 0 && ydiff == 0)
    474 			return ("Would already be there");
    475 		p.new_dir = DIR_FROM_DXDY(xdiff, ydiff);
    476 		if (p.new_dir == p.dir)
    477 			return ("Already going in that direction");
    478 	}
    479 	return (NULL);
    480 }
    481 
    482 const char	*
    483 beacon(c)
    484 	char c __attribute__((__unused__));
    485 {
    486 	dest_type = T_BEACON;
    487 	return (NULL);
    488 }
    489 
    490 const char	*
    491 ex_it(c)
    492 	char c __attribute__((__unused__));
    493 {
    494 	dest_type = T_EXIT;
    495 	return (NULL);
    496 }
    497 
    498 const char	*
    499 airport(c)
    500 	char c __attribute__((__unused__));
    501 {
    502 	dest_type = T_AIRPORT;
    503 	return (NULL);
    504 }
    505 
    506 const char	*
    507 climb(c)
    508 	char c __attribute__((__unused__));
    509 {
    510 	dir = D_UP;
    511 	return (NULL);
    512 }
    513 
    514 const char	*
    515 descend(c)
    516 	char c __attribute__((__unused__));
    517 {
    518 	dir = D_DOWN;
    519 	return (NULL);
    520 }
    521 
    522 const char	*
    523 setalt(c)
    524 	char c;
    525 {
    526 	if ((p.altitude == c - '0') && (p.new_altitude == p.altitude))
    527 		return ("Already at that altitude");
    528 	p.new_altitude = c - '0';
    529 	return (NULL);
    530 }
    531 
    532 const char	*
    533 setrelalt(c)
    534 	char c;
    535 {
    536 	if (c == 0)
    537 		return ("altitude not changed");
    538 
    539 	switch (dir) {
    540 	case D_UP:
    541 		p.new_altitude = p.altitude + c - '0';
    542 		break;
    543 	case D_DOWN:
    544 		p.new_altitude = p.altitude - (c - '0');
    545 		break;
    546 	default:
    547 		return ("Unknown case in setrelalt!  Get help!");
    548 		break;
    549 	}
    550 	if (p.new_altitude < 0)
    551 		return ("Altitude would be too low");
    552 	else if (p.new_altitude > 9)
    553 		return ("Altitude would be too high");
    554 	return (NULL);
    555 }
    556 
    557 const char	*
    558 benum(c)
    559 	char c;
    560 {
    561 	dest_no = c -= '0';
    562 
    563 	switch (dest_type) {
    564 	case T_BEACON:
    565 		if (c >= sp->num_beacons)
    566 			return ("Unknown beacon");
    567 		p.new_dir = DIR_FROM_DXDY(sp->beacon[(int)c].x - p.xpos,
    568 			sp->beacon[(int)c].y - p.ypos);
    569 		break;
    570 	case T_EXIT:
    571 		if (c >= sp->num_exits)
    572 			return ("Unknown exit");
    573 		p.new_dir = DIR_FROM_DXDY(sp->exit[(int)c].x - p.xpos,
    574 			sp->exit[(int)c].y - p.ypos);
    575 		break;
    576 	case T_AIRPORT:
    577 		if (c >= sp->num_airports)
    578 			return ("Unknown airport");
    579 		p.new_dir = DIR_FROM_DXDY(sp->airport[(int)c].x - p.xpos,
    580 			sp->airport[(int)c].y - p.ypos);
    581 		break;
    582 	default:
    583 		return ("Unknown case in benum!  Get help!");
    584 		break;
    585 	}
    586 	return (NULL);
    587 }
    588 
    589 const char	*
    590 to_dir(c)
    591 	char c;
    592 {
    593 	p.new_dir = dir_no(c);
    594 	return (NULL);
    595 }
    596 
    597 const char	*
    598 rel_dir(c)
    599 	char c;
    600 {
    601 	int	angle;
    602 
    603 	angle = dir_no(c);
    604 	switch (dir) {
    605 	case D_LEFT:
    606 		p.new_dir = p.dir - angle;
    607 		if (p.new_dir < 0)
    608 			p.new_dir += MAXDIR;
    609 		break;
    610 	case D_RIGHT:
    611 		p.new_dir = p.dir + angle;
    612 		if (p.new_dir >= MAXDIR)
    613 			p.new_dir -= MAXDIR;
    614 		break;
    615 	default:
    616 		return ("Bizarre direction in rel_dir!  Get help!");
    617 		break;
    618 	}
    619 	return (NULL);
    620 }
    621 
    622 const char	*
    623 mark(c)
    624 	char c __attribute__((__unused__));
    625 {
    626 	if (p.altitude == 0)
    627 		return ("Cannot mark planes on the ground");
    628 	if (p.status == S_MARKED)
    629 		return ("Already marked");
    630 	p.status = S_MARKED;
    631 	return (NULL);
    632 }
    633 
    634 const char	*
    635 unmark(c)
    636 	char c __attribute__((__unused__));
    637 {
    638 	if (p.altitude == 0)
    639 		return ("Cannot unmark planes on the ground");
    640 	if (p.status == S_UNMARKED)
    641 		return ("Already unmarked");
    642 	p.status = S_UNMARKED;
    643 	return (NULL);
    644 }
    645 
    646 const char	*
    647 ignore(c)
    648 	char c __attribute__((__unused__));
    649 {
    650 	if (p.altitude == 0)
    651 		return ("Cannot ignore planes on the ground");
    652 	if (p.status == S_IGNORED)
    653 		return ("Already ignored");
    654 	p.status = S_IGNORED;
    655 	return (NULL);
    656 }
    657 
    658 int
    659 dir_no(ch)
    660 	char	ch;
    661 {
    662 	int	dir;
    663 
    664 	dir = -1;
    665 	switch (ch) {
    666 	case 'w':	dir = 0;	break;
    667 	case 'e':	dir = 1;	break;
    668 	case 'd':	dir = 2;	break;
    669 	case 'c':	dir = 3;	break;
    670 	case 'x':	dir = 4;	break;
    671 	case 'z':	dir = 5;	break;
    672 	case 'a':	dir = 6;	break;
    673 	case 'q':	dir = 7;	break;
    674 	default:
    675 		fprintf(stderr, "bad character in dir_no\n");
    676 		break;
    677 	}
    678 	return (dir);
    679 }
    680