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      1  1.30    rillig /*	$NetBSD: input.c,v 1.30 2021/05/02 12:50:43 rillig Exp $	*/
      2   1.3       cgd 
      3   1.1       cgd /*-
      4   1.3       cgd  * Copyright (c) 1990, 1993
      5   1.3       cgd  *	The Regents of the University of California.  All rights reserved.
      6   1.1       cgd  *
      7   1.1       cgd  * This code is derived from software contributed to Berkeley by
      8   1.1       cgd  * Ed James.
      9   1.1       cgd  *
     10   1.1       cgd  * Redistribution and use in source and binary forms, with or without
     11   1.1       cgd  * modification, are permitted provided that the following conditions
     12   1.1       cgd  * are met:
     13   1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     14   1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     15   1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     16   1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     17   1.1       cgd  *    documentation and/or other materials provided with the distribution.
     18  1.15       agc  * 3. Neither the name of the University nor the names of its contributors
     19   1.1       cgd  *    may be used to endorse or promote products derived from this software
     20   1.1       cgd  *    without specific prior written permission.
     21   1.1       cgd  *
     22   1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23   1.1       cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24   1.1       cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25   1.1       cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26   1.1       cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27   1.1       cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28   1.1       cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29   1.1       cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30   1.1       cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31   1.1       cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32   1.1       cgd  * SUCH DAMAGE.
     33   1.1       cgd  */
     34   1.1       cgd 
     35   1.1       cgd /*
     36   1.1       cgd  * Copyright (c) 1987 by Ed James, UC Berkeley.  All rights reserved.
     37   1.1       cgd  *
     38   1.1       cgd  * Copy permission is hereby granted provided that this notice is
     39   1.1       cgd  * retained on all partial or complete copies.
     40   1.1       cgd  *
     41   1.1       cgd  * For more info on this and all of my stuff, mail edjames (at) berkeley.edu.
     42   1.1       cgd  */
     43   1.1       cgd 
     44   1.6     lukem #include <sys/cdefs.h>
     45   1.1       cgd #ifndef lint
     46   1.3       cgd #if 0
     47   1.3       cgd static char sccsid[] = "@(#)input.c	8.1 (Berkeley) 5/31/93";
     48   1.3       cgd #else
     49  1.30    rillig __RCSID("$NetBSD: input.c,v 1.30 2021/05/02 12:50:43 rillig Exp $");
     50   1.3       cgd #endif
     51  1.14       cgd #endif /* not lint */
     52   1.1       cgd 
     53  1.29  dholland #include <sys/types.h>
     54  1.29  dholland #include <sys/wait.h>
     55  1.29  dholland #include <stdio.h>
     56  1.29  dholland #include <stdlib.h>
     57  1.29  dholland #include <string.h>
     58  1.29  dholland #include <unistd.h>
     59  1.29  dholland #include <termios.h>
     60  1.29  dholland #include <ctype.h>
     61  1.29  dholland #include <assert.h>
     62  1.29  dholland #include <math.h>
     63  1.29  dholland 
     64   1.1       cgd #include "pathnames.h"
     65  1.29  dholland #include "def.h"
     66  1.29  dholland #include "struct.h"
     67  1.29  dholland #include "extern.h"
     68  1.29  dholland #include "tunable.h"
     69   1.1       cgd 
     70  1.24  dholland static void rezero(void);
     71  1.24  dholland static void noise(void);
     72  1.24  dholland static int gettoken(void);
     73  1.24  dholland static const char *setplane(int);
     74  1.24  dholland static const char *turn(int);
     75  1.24  dholland static const char *circle(int);
     76  1.24  dholland static const char *left(int);
     77  1.24  dholland static const char *right(int);
     78  1.24  dholland static const char *Left(int);
     79  1.24  dholland static const char *Right(int);
     80  1.24  dholland static const char *delayb(int);
     81  1.24  dholland static const char *beacon(int);
     82  1.24  dholland static const char *ex_it(int);
     83  1.24  dholland static const char *airport(int);
     84  1.24  dholland static const char *climb(int);
     85  1.24  dholland static const char *descend(int);
     86  1.24  dholland static const char *setalt(int);
     87  1.24  dholland static const char *setrelalt(int);
     88  1.24  dholland static const char *benum(int);
     89  1.24  dholland static const char *to_dir(int);
     90  1.24  dholland static const char *rel_dir(int);
     91  1.24  dholland static const char *mark(int);
     92  1.24  dholland static const char *unmark(int);
     93  1.24  dholland static const char *ignore(int);
     94  1.24  dholland 
     95  1.24  dholland 
     96  1.24  dholland 
     97   1.1       cgd #define MAXRULES	6
     98   1.1       cgd #define MAXDEPTH	15
     99   1.1       cgd 
    100   1.1       cgd #define RETTOKEN	'\n'
    101   1.1       cgd #define REDRAWTOKEN	'\014'	/* CTRL(L) */
    102   1.1       cgd #define	SHELLTOKEN	'!'
    103   1.1       cgd #define HELPTOKEN	'?'
    104   1.1       cgd #define ALPHATOKEN	256
    105   1.1       cgd #define NUMTOKEN	257
    106   1.1       cgd 
    107   1.1       cgd typedef struct {
    108   1.1       cgd 	int	token;
    109   1.1       cgd 	int	to_state;
    110  1.11   hubertf 	const char	*str;
    111  1.18       jmc 	const char	*(*func)(int);
    112   1.1       cgd } RULE;
    113   1.1       cgd 
    114   1.1       cgd typedef struct {
    115   1.1       cgd 	int	num_rules;
    116   1.1       cgd 	RULE	*rule;
    117   1.1       cgd } STATE;
    118   1.1       cgd 
    119   1.1       cgd typedef struct {
    120   1.1       cgd 	char	str[20];
    121   1.1       cgd 	int	state;
    122   1.1       cgd 	int	rule;
    123   1.1       cgd 	int	ch;
    124   1.1       cgd 	int	pos;
    125   1.1       cgd } STACK;
    126   1.1       cgd 
    127   1.1       cgd #define T_RULE		stack[level].rule
    128   1.1       cgd #define T_STATE		stack[level].state
    129   1.1       cgd #define T_STR		stack[level].str
    130   1.1       cgd #define T_POS		stack[level].pos
    131   1.1       cgd #define	T_CH		stack[level].ch
    132   1.1       cgd 
    133   1.1       cgd #define NUMELS(a)	(sizeof (a) / sizeof (*(a)))
    134   1.1       cgd 
    135   1.1       cgd #define NUMSTATES	NUMELS(st)
    136   1.1       cgd 
    137  1.24  dholland static
    138   1.1       cgd RULE	state0[] = {	{ ALPHATOKEN,	1,	"%c:",		setplane},
    139   1.1       cgd 			{ RETTOKEN,	-1,	"",		NULL	},
    140   1.1       cgd 			{ HELPTOKEN,	12,	" [a-z]<ret>",	NULL	}},
    141  1.30    rillig 	state1[] = {	{ 't',		2,	" turn",	turn	},
    142  1.30    rillig 			{ 'a',		3,	" altitude:",	NULL	},
    143   1.1       cgd 			{ 'c',		4,	" circle",	circle	},
    144   1.1       cgd 			{ 'm',		7,	" mark",	mark	},
    145   1.1       cgd 			{ 'u',		7,	" unmark",	unmark	},
    146   1.1       cgd 			{ 'i',		7,	" ignore",	ignore	},
    147   1.1       cgd 			{ HELPTOKEN,	12,	" tacmui",	NULL	}},
    148  1.30    rillig 	state2[] = {	{ 'l',		6,	" left",	left	},
    149  1.30    rillig 			{ 'r',		6,	" right",	right	},
    150   1.1       cgd 			{ 'L',		4,	" left 90",	Left	},
    151  1.30    rillig 			{ 'R',		4,	" right 90",	Right	},
    152   1.1       cgd 			{ 't',		11,	" towards",	NULL	},
    153   1.1       cgd 			{ 'w',		4,	" to 0",	to_dir	},
    154   1.1       cgd 			{ 'e',		4,	" to 45",	to_dir	},
    155   1.1       cgd 			{ 'd',		4,	" to 90",	to_dir	},
    156   1.1       cgd 			{ 'c',		4,	" to 135",	to_dir	},
    157   1.1       cgd 			{ 'x',		4,	" to 180",	to_dir	},
    158   1.1       cgd 			{ 'z',		4,	" to 225",	to_dir	},
    159   1.1       cgd 			{ 'a',		4,	" to 270",	to_dir	},
    160   1.1       cgd 			{ 'q',		4,	" to 315",	to_dir	},
    161   1.1       cgd 			{ HELPTOKEN,	12,	" lrLRt<dir>",	NULL	}},
    162  1.30    rillig 	state3[] = {	{ '+',		10,	" climb",	climb	},
    163  1.30    rillig 			{ 'c',		10,	" climb",	climb	},
    164  1.30    rillig 			{ '-',		10,	" descend",	descend	},
    165  1.30    rillig 			{ 'd',		10,	" descend",	descend	},
    166   1.1       cgd 			{ NUMTOKEN,	7,	" %c000 feet",	setalt	},
    167   1.1       cgd 			{ HELPTOKEN,	12,	" +-cd[0-9]",	NULL	}},
    168  1.30    rillig 	state4[] = {	{ '@',		9,	" at",		NULL	},
    169  1.30    rillig 			{ 'a',		9,	" at",		NULL	},
    170   1.1       cgd 			{ RETTOKEN,	-1,	"",		NULL	},
    171   1.1       cgd 			{ HELPTOKEN,	12,	" @a<ret>",	NULL	}},
    172   1.1       cgd 	state5[] = {	{ NUMTOKEN,	7,	"%c",		delayb	},
    173   1.1       cgd 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    174   1.1       cgd 	state6[] = {	{ '@',		9,	" at",		NULL	},
    175   1.1       cgd 			{ 'a',		9,	" at",		NULL	},
    176   1.1       cgd 			{ 'w',		4,	" 0",		rel_dir	},
    177   1.1       cgd 			{ 'e',		4,	" 45",		rel_dir	},
    178   1.1       cgd 			{ 'd',		4,	" 90",		rel_dir	},
    179   1.1       cgd 			{ 'c',		4,	" 135",		rel_dir	},
    180   1.1       cgd 			{ 'x',		4,	" 180",		rel_dir	},
    181   1.1       cgd 			{ 'z',		4,	" 225",		rel_dir	},
    182   1.1       cgd 			{ 'a',		4,	" 270",		rel_dir	},
    183   1.1       cgd 			{ 'q',		4,	" 315",		rel_dir	},
    184  1.30    rillig 			{ RETTOKEN,	-1,	"",		NULL	},
    185   1.1       cgd 			{ HELPTOKEN,	12,	" @a<dir><ret>",NULL	}},
    186   1.1       cgd 	state7[] = {	{ RETTOKEN,	-1,	"",		NULL	},
    187   1.1       cgd 			{ HELPTOKEN,	12,	" <ret>",	NULL	}},
    188   1.1       cgd 	state8[] = {	{ NUMTOKEN,	4,	"%c",		benum	},
    189   1.1       cgd 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    190   1.1       cgd 	state9[] = {	{ 'b',		5,	" beacon #",	NULL	},
    191   1.1       cgd 			{ '*',		5,	" beacon #",	NULL	},
    192   1.1       cgd 			{ HELPTOKEN,	12,	" b*",		NULL	}},
    193   1.1       cgd 	state10[] = {	{ NUMTOKEN,	7,	" %c000 ft",	setrelalt},
    194   1.1       cgd 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    195  1.30    rillig 	state11[] = {	{ 'b',		8,	" beacon #",	beacon	},
    196   1.1       cgd 			{ '*',		8,	" beacon #",	beacon	},
    197   1.1       cgd 			{ 'e',		8,	" exit #",	ex_it	},
    198   1.1       cgd 			{ 'a',		8,	" airport #",	airport	},
    199   1.1       cgd 			{ HELPTOKEN,	12,	" b*ea",	NULL	}},
    200   1.1       cgd 	state12[] = {	{ -1,		-1,	"",		NULL	}};
    201   1.1       cgd 
    202   1.1       cgd #define DEF_STATE(s)	{ NUMELS(s),	(s)	}
    203   1.1       cgd 
    204  1.24  dholland static STATE st[] = {
    205   1.1       cgd 	DEF_STATE(state0), DEF_STATE(state1), DEF_STATE(state2),
    206   1.1       cgd 	DEF_STATE(state3), DEF_STATE(state4), DEF_STATE(state5),
    207   1.1       cgd 	DEF_STATE(state6), DEF_STATE(state7), DEF_STATE(state8),
    208   1.1       cgd 	DEF_STATE(state9), DEF_STATE(state10), DEF_STATE(state11),
    209   1.1       cgd 	DEF_STATE(state12)
    210   1.1       cgd };
    211   1.1       cgd 
    212  1.24  dholland static PLANE p;
    213  1.24  dholland static STACK stack[MAXDEPTH];
    214  1.24  dholland static int level;
    215  1.24  dholland static int tval;
    216  1.28  dholland static int dir;
    217  1.28  dholland static enum places dest_type;
    218  1.27  dholland static unsigned dest_no;
    219   1.1       cgd 
    220  1.24  dholland static int
    221  1.18       jmc pop(void)
    222   1.1       cgd {
    223   1.1       cgd 	if (level == 0)
    224   1.1       cgd 		return (-1);
    225   1.1       cgd 	level--;
    226   1.1       cgd 
    227   1.1       cgd 	ioclrtoeol(T_POS);
    228   1.1       cgd 
    229  1.19    rpaulo 	(void)strcpy(T_STR, "");
    230   1.1       cgd 	T_RULE = -1;
    231   1.1       cgd 	T_CH = -1;
    232   1.1       cgd 	return (0);
    233   1.1       cgd }
    234   1.1       cgd 
    235  1.24  dholland static void
    236  1.18       jmc rezero(void)
    237   1.1       cgd {
    238   1.1       cgd 	iomove(0);
    239   1.1       cgd 
    240   1.1       cgd 	level = 0;
    241   1.1       cgd 	T_STATE = 0;
    242   1.1       cgd 	T_RULE = -1;
    243   1.1       cgd 	T_CH = -1;
    244   1.1       cgd 	T_POS = 0;
    245  1.19    rpaulo 	(void)strcpy(T_STR, "");
    246   1.1       cgd }
    247   1.1       cgd 
    248  1.24  dholland static void
    249  1.18       jmc push(int ruleno, int ch)
    250   1.1       cgd {
    251   1.1       cgd 	int	newstate, newpos;
    252   1.1       cgd 
    253  1.20   jnemeth 	assert(level < (MAXDEPTH - 1));
    254  1.23  dholland 	(void)snprintf(T_STR, sizeof(T_STR),
    255  1.23  dholland 		st[T_STATE].rule[ruleno].str, tval);
    256   1.1       cgd 	T_RULE = ruleno;
    257   1.1       cgd 	T_CH = ch;
    258   1.1       cgd 	newstate = st[T_STATE].rule[ruleno].to_state;
    259   1.1       cgd 	newpos = T_POS + strlen(T_STR);
    260   1.1       cgd 
    261   1.1       cgd 	ioaddstr(T_POS, T_STR);
    262   1.1       cgd 
    263   1.1       cgd 	if (level == 0)
    264   1.1       cgd 		ioclrtobot();
    265   1.1       cgd 	level++;
    266   1.1       cgd 	T_STATE = newstate;
    267   1.1       cgd 	T_POS = newpos;
    268   1.1       cgd 	T_RULE = -1;
    269  1.19    rpaulo 	(void)strcpy(T_STR, "");
    270   1.1       cgd }
    271   1.1       cgd 
    272   1.6     lukem int
    273  1.18       jmc getcommand(void)
    274   1.1       cgd {
    275   1.1       cgd 	int	c, i, done;
    276  1.18       jmc 	const char	*s, *(*func)(int);
    277   1.1       cgd 	PLANE	*pp;
    278   1.1       cgd 
    279   1.1       cgd 	rezero();
    280   1.1       cgd 
    281   1.1       cgd 	do {
    282   1.1       cgd 		c = gettoken();
    283   1.4   mycroft 		if (c == tty_new.c_cc[VERASE]) {
    284   1.1       cgd 			if (pop() < 0)
    285   1.1       cgd 				noise();
    286   1.4   mycroft 		} else if (c == tty_new.c_cc[VKILL]) {
    287   1.1       cgd 			while (pop() >= 0)
    288   1.1       cgd 				;
    289   1.1       cgd 		} else {
    290   1.1       cgd 			done = 0;
    291   1.1       cgd 			for (i = 0; i < st[T_STATE].num_rules; i++) {
    292   1.1       cgd 				if (st[T_STATE].rule[i].token == c ||
    293   1.1       cgd 				    st[T_STATE].rule[i].token == tval) {
    294   1.1       cgd 					push(i, (c >= ALPHATOKEN) ? tval : c);
    295   1.1       cgd 					done = 1;
    296   1.1       cgd 					break;
    297   1.1       cgd 				}
    298   1.1       cgd 			}
    299   1.1       cgd 			if (!done)
    300   1.1       cgd 				noise();
    301   1.1       cgd 		}
    302   1.1       cgd 	} while (T_STATE != -1);
    303   1.1       cgd 
    304   1.1       cgd 	if (level == 1)
    305   1.1       cgd 		return (1);	/* forced update */
    306   1.1       cgd 
    307   1.1       cgd 	dest_type = T_NODEST;
    308  1.30    rillig 
    309   1.1       cgd 	for (i = 0; i < level; i++) {
    310   1.1       cgd 		func = st[stack[i].state].rule[stack[i].rule].func;
    311   1.1       cgd 		if (func != NULL)
    312   1.1       cgd 			if ((s = (*func)(stack[i].ch)) != NULL) {
    313  1.30    rillig 				ioerror(stack[i].pos,
    314  1.19    rpaulo 				    (int)strlen(stack[i].str), s);
    315   1.1       cgd 				return (-1);
    316   1.1       cgd 			}
    317   1.1       cgd 	}
    318   1.1       cgd 
    319   1.1       cgd 	pp = findplane(p.plane_no);
    320   1.1       cgd 	if (pp->new_altitude != p.new_altitude)
    321   1.1       cgd 		pp->new_altitude = p.new_altitude;
    322   1.1       cgd 	else if (pp->status != p.status)
    323   1.1       cgd 		pp->status = p.status;
    324   1.1       cgd 	else {
    325   1.1       cgd 		pp->new_dir = p.new_dir;
    326   1.1       cgd 		pp->delayd = p.delayd;
    327   1.1       cgd 		pp->delayd_no = p.delayd_no;
    328   1.1       cgd 	}
    329   1.1       cgd 	return (0);
    330   1.1       cgd }
    331   1.1       cgd 
    332  1.24  dholland static void
    333  1.18       jmc noise(void)
    334   1.1       cgd {
    335  1.19    rpaulo 	(void)putchar('\07');
    336  1.19    rpaulo 	(void)fflush(stdout);
    337   1.1       cgd }
    338   1.1       cgd 
    339  1.24  dholland static int
    340  1.18       jmc gettoken(void)
    341   1.1       cgd {
    342   1.1       cgd 	while ((tval = getAChar()) == REDRAWTOKEN || tval == SHELLTOKEN)
    343   1.1       cgd 	{
    344   1.1       cgd 		if (tval == SHELLTOKEN)
    345   1.1       cgd 		{
    346   1.1       cgd #ifdef BSD
    347   1.1       cgd 			struct itimerval	itv;
    348   1.1       cgd 			itv.it_value.tv_sec = 0;
    349   1.1       cgd 			itv.it_value.tv_usec = 0;
    350  1.19    rpaulo 			(void)setitimer(ITIMER_REAL, &itv, NULL);
    351   1.1       cgd #endif
    352   1.1       cgd #ifdef SYSV
    353   1.1       cgd 			int aval;
    354   1.1       cgd 			aval = alarm(0);
    355   1.1       cgd #endif
    356   1.1       cgd 			if (fork() == 0)	/* child */
    357   1.1       cgd 			{
    358   1.6     lukem 				char *shell, *base;
    359   1.1       cgd 
    360   1.1       cgd 				done_screen();
    361   1.1       cgd 
    362   1.1       cgd 						 /* run user's favorite shell */
    363   1.1       cgd 				if ((shell = getenv("SHELL")) != NULL)
    364   1.1       cgd 				{
    365   1.1       cgd 					base = strrchr(shell, '/');
    366   1.1       cgd 					if (base == NULL)
    367   1.1       cgd 						base = shell;
    368   1.1       cgd 					else
    369   1.1       cgd 						base++;
    370  1.19    rpaulo 					(void)execl(shell, base, (char *) 0);
    371   1.1       cgd 				}
    372   1.1       cgd 				else
    373  1.30    rillig 					(void)execl(_PATH_BSHELL, "sh",
    374  1.19    rpaulo 					    (char *) 0);
    375   1.1       cgd 
    376   1.1       cgd 				exit(0);	/* oops */
    377   1.1       cgd 			}
    378   1.1       cgd 
    379  1.19    rpaulo 			(void)wait(0);
    380  1.19    rpaulo 			(void)tcsetattr(fileno(stdin), TCSADRAIN, &tty_new);
    381   1.1       cgd #ifdef BSD
    382   1.1       cgd 			itv.it_value.tv_sec = 0;
    383   1.1       cgd 			itv.it_value.tv_usec = 1;
    384   1.1       cgd 			itv.it_interval.tv_sec = sp->update_secs;
    385   1.1       cgd 			itv.it_interval.tv_usec = 0;
    386  1.19    rpaulo 			(void)setitimer(ITIMER_REAL, &itv, NULL);
    387   1.1       cgd #endif
    388   1.1       cgd #ifdef SYSV
    389   1.1       cgd 			alarm(aval);
    390   1.1       cgd #endif
    391   1.1       cgd 		}
    392  1.19    rpaulo 		(void)redraw();
    393   1.1       cgd 	}
    394   1.1       cgd 
    395   1.1       cgd 	if (isdigit(tval))
    396   1.1       cgd 		return (NUMTOKEN);
    397   1.1       cgd 	else if (isalpha(tval))
    398   1.1       cgd 		return (ALPHATOKEN);
    399   1.1       cgd 	else
    400   1.1       cgd 		return (tval);
    401   1.1       cgd }
    402   1.1       cgd 
    403  1.24  dholland static const char *
    404  1.18       jmc setplane(int c)
    405   1.1       cgd {
    406   1.1       cgd 	PLANE	*pp;
    407   1.1       cgd 
    408   1.1       cgd 	pp = findplane(number(c));
    409   1.1       cgd 	if (pp == NULL)
    410   1.1       cgd 		return ("Unknown Plane");
    411  1.19    rpaulo 	(void)memcpy(&p, pp, sizeof (p));
    412  1.26  dholland 	p.delayd = false;
    413   1.1       cgd 	return (NULL);
    414   1.1       cgd }
    415   1.1       cgd 
    416  1.19    rpaulo /* ARGSUSED */
    417  1.24  dholland static const char *
    418  1.22     perry turn(int c __unused)
    419   1.1       cgd {
    420   1.1       cgd 	if (p.altitude == 0)
    421   1.1       cgd 		return ("Planes at airports may not change direction");
    422   1.1       cgd 	return (NULL);
    423   1.1       cgd }
    424   1.1       cgd 
    425  1.19    rpaulo /* ARGSUSED */
    426  1.24  dholland static const char *
    427  1.22     perry circle(int c __unused)
    428   1.1       cgd {
    429   1.1       cgd 	if (p.altitude == 0)
    430   1.1       cgd 		return ("Planes cannot circle on the ground");
    431   1.1       cgd 	p.new_dir = MAXDIR;
    432   1.1       cgd 	return (NULL);
    433   1.1       cgd }
    434   1.1       cgd 
    435  1.19    rpaulo /* ARGSUSED */
    436  1.24  dholland static const char *
    437  1.22     perry left(int c __unused)
    438   1.1       cgd {
    439   1.1       cgd 	dir = D_LEFT;
    440   1.1       cgd 	p.new_dir = p.dir - 1;
    441   1.1       cgd 	if (p.new_dir < 0)
    442   1.1       cgd 		p.new_dir += MAXDIR;
    443   1.1       cgd 	return (NULL);
    444   1.1       cgd }
    445   1.1       cgd 
    446  1.19    rpaulo /* ARGSUSED */
    447  1.24  dholland static const char *
    448  1.22     perry right(int c __unused)
    449   1.1       cgd {
    450   1.1       cgd 	dir = D_RIGHT;
    451   1.1       cgd 	p.new_dir = p.dir + 1;
    452   1.9    briggs 	if (p.new_dir >= MAXDIR)
    453   1.1       cgd 		p.new_dir -= MAXDIR;
    454   1.1       cgd 	return (NULL);
    455   1.1       cgd }
    456   1.1       cgd 
    457  1.19    rpaulo /* ARGSUSED */
    458  1.24  dholland static const char *
    459  1.22     perry Left(int c __unused)
    460   1.1       cgd {
    461   1.1       cgd 	p.new_dir = p.dir - 2;
    462   1.1       cgd 	if (p.new_dir < 0)
    463   1.1       cgd 		p.new_dir += MAXDIR;
    464   1.1       cgd 	return (NULL);
    465   1.1       cgd }
    466   1.1       cgd 
    467  1.19    rpaulo /* ARGSUSED */
    468  1.24  dholland static const char *
    469  1.22     perry Right(int c __unused)
    470   1.1       cgd {
    471   1.1       cgd 	p.new_dir = p.dir + 2;
    472   1.8    briggs 	if (p.new_dir >= MAXDIR)
    473   1.1       cgd 		p.new_dir -= MAXDIR;
    474   1.1       cgd 	return (NULL);
    475   1.1       cgd }
    476   1.1       cgd 
    477  1.24  dholland static const char *
    478  1.25  dholland delayb(int ch)
    479   1.1       cgd {
    480   1.1       cgd 	int	xdiff, ydiff;
    481  1.25  dholland 	unsigned bn;
    482   1.1       cgd 
    483  1.25  dholland 	bn = ch -= '0';
    484   1.1       cgd 
    485  1.25  dholland 	if (bn >= sp->num_beacons)
    486   1.1       cgd 		return ("Unknown beacon");
    487  1.25  dholland 	xdiff = sp->beacon[bn].x - p.xpos;
    488   1.1       cgd 	xdiff = SGN(xdiff);
    489  1.25  dholland 	ydiff = sp->beacon[bn].y - p.ypos;
    490   1.1       cgd 	ydiff = SGN(ydiff);
    491   1.1       cgd 	if (xdiff != displacement[p.dir].dx || ydiff != displacement[p.dir].dy)
    492   1.1       cgd 		return ("Beacon is not in flight path");
    493  1.26  dholland 	p.delayd = true;
    494  1.25  dholland 	p.delayd_no = bn;
    495   1.1       cgd 
    496   1.1       cgd 	if (dest_type != T_NODEST) {
    497   1.1       cgd 		switch (dest_type) {
    498   1.1       cgd 		case T_BEACON:
    499  1.25  dholland 			xdiff = sp->beacon[dest_no].x - sp->beacon[bn].x;
    500  1.25  dholland 			ydiff = sp->beacon[dest_no].y - sp->beacon[bn].y;
    501   1.1       cgd 			break;
    502   1.1       cgd 		case T_EXIT:
    503  1.25  dholland 			xdiff = sp->exit[dest_no].x - sp->beacon[bn].x;
    504  1.25  dholland 			ydiff = sp->exit[dest_no].y - sp->beacon[bn].y;
    505   1.1       cgd 			break;
    506   1.1       cgd 		case T_AIRPORT:
    507  1.25  dholland 			xdiff = sp->airport[dest_no].x - sp->beacon[bn].x;
    508  1.25  dholland 			ydiff = sp->airport[dest_no].y - sp->beacon[bn].y;
    509   1.1       cgd 			break;
    510   1.1       cgd 		default:
    511   1.1       cgd 			return ("Bad case in delayb!  Get help!");
    512   1.1       cgd 		}
    513   1.1       cgd 		if (xdiff == 0 && ydiff == 0)
    514   1.1       cgd 			return ("Would already be there");
    515   1.1       cgd 		p.new_dir = DIR_FROM_DXDY(xdiff, ydiff);
    516   1.1       cgd 		if (p.new_dir == p.dir)
    517   1.1       cgd 			return ("Already going in that direction");
    518   1.1       cgd 	}
    519   1.1       cgd 	return (NULL);
    520   1.1       cgd }
    521   1.1       cgd 
    522  1.19    rpaulo /* ARGSUSED */
    523  1.24  dholland static const char *
    524  1.22     perry beacon(int c __unused)
    525   1.1       cgd {
    526   1.1       cgd 	dest_type = T_BEACON;
    527   1.1       cgd 	return (NULL);
    528   1.1       cgd }
    529   1.1       cgd 
    530  1.19    rpaulo /* ARGSUSED */
    531  1.24  dholland static const char *
    532  1.22     perry ex_it(int c __unused)
    533   1.1       cgd {
    534   1.1       cgd 	dest_type = T_EXIT;
    535   1.1       cgd 	return (NULL);
    536   1.1       cgd }
    537   1.1       cgd 
    538  1.19    rpaulo /* ARGSUSED */
    539  1.24  dholland static const char *
    540  1.22     perry airport(int c __unused)
    541   1.1       cgd {
    542   1.1       cgd 	dest_type = T_AIRPORT;
    543   1.1       cgd 	return (NULL);
    544   1.1       cgd }
    545   1.1       cgd 
    546  1.19    rpaulo /* ARGSUSED */
    547  1.24  dholland static const char *
    548  1.22     perry climb(int c __unused)
    549   1.1       cgd {
    550   1.1       cgd 	dir = D_UP;
    551   1.1       cgd 	return (NULL);
    552   1.1       cgd }
    553   1.1       cgd 
    554  1.19    rpaulo /* ARGSUSED */
    555  1.24  dholland static const char *
    556  1.22     perry descend(int c __unused)
    557   1.1       cgd {
    558   1.1       cgd 	dir = D_DOWN;
    559   1.1       cgd 	return (NULL);
    560   1.1       cgd }
    561   1.1       cgd 
    562  1.24  dholland static const char *
    563  1.18       jmc setalt(int c)
    564   1.1       cgd {
    565  1.21      elad 	int newalt = c - '0';
    566  1.21      elad 	if ((p.altitude == newalt) && (p.new_altitude == p.altitude))
    567   1.1       cgd 		return ("Already at that altitude");
    568  1.21      elad 	if (p.new_altitude == newalt) {
    569  1.21      elad 		return ("Already going to that altitude");
    570  1.21      elad 	}
    571  1.21      elad 	p.new_altitude = newalt;
    572   1.1       cgd 	return (NULL);
    573   1.1       cgd }
    574   1.1       cgd 
    575  1.24  dholland static const char *
    576  1.18       jmc setrelalt(int c)
    577   1.1       cgd {
    578  1.21      elad 	int newalt;
    579  1.21      elad 
    580   1.1       cgd 	if (c == 0)
    581   1.1       cgd 		return ("altitude not changed");
    582   1.1       cgd 
    583   1.1       cgd 	switch (dir) {
    584   1.1       cgd 	case D_UP:
    585  1.21      elad 		newalt = p.altitude + c - '0';
    586   1.1       cgd 		break;
    587   1.1       cgd 	case D_DOWN:
    588  1.21      elad 		newalt = p.altitude - (c - '0');
    589   1.1       cgd 		break;
    590   1.1       cgd 	default:
    591   1.1       cgd 		return ("Unknown case in setrelalt!  Get help!");
    592   1.1       cgd 	}
    593  1.21      elad 
    594  1.21      elad 	if (p.new_altitude == newalt)
    595  1.21      elad 		return ("Already going to that altitude");
    596  1.21      elad 
    597  1.21      elad 	p.new_altitude = newalt;
    598  1.21      elad 
    599   1.1       cgd 	if (p.new_altitude < 0)
    600   1.1       cgd 		return ("Altitude would be too low");
    601   1.1       cgd 	else if (p.new_altitude > 9)
    602   1.1       cgd 		return ("Altitude would be too high");
    603   1.1       cgd 	return (NULL);
    604   1.1       cgd }
    605   1.1       cgd 
    606  1.24  dholland static const char *
    607  1.25  dholland benum(int ch)
    608   1.1       cgd {
    609  1.25  dholland 	unsigned n;
    610  1.25  dholland 
    611  1.25  dholland 	n = ch - '0';
    612  1.25  dholland 	dest_no = n;
    613   1.1       cgd 
    614   1.1       cgd 	switch (dest_type) {
    615   1.1       cgd 	case T_BEACON:
    616  1.25  dholland 		if (n >= sp->num_beacons)
    617   1.1       cgd 			return ("Unknown beacon");
    618  1.25  dholland 		p.new_dir = DIR_FROM_DXDY(sp->beacon[n].x - p.xpos,
    619  1.25  dholland 			sp->beacon[n].y - p.ypos);
    620   1.1       cgd 		break;
    621   1.1       cgd 	case T_EXIT:
    622  1.25  dholland 		if (n >= sp->num_exits)
    623   1.1       cgd 			return ("Unknown exit");
    624  1.25  dholland 		p.new_dir = DIR_FROM_DXDY(sp->exit[n].x - p.xpos,
    625  1.25  dholland 			sp->exit[n].y - p.ypos);
    626   1.1       cgd 		break;
    627   1.1       cgd 	case T_AIRPORT:
    628  1.25  dholland 		if (n >= sp->num_airports)
    629   1.1       cgd 			return ("Unknown airport");
    630  1.25  dholland 		p.new_dir = DIR_FROM_DXDY(sp->airport[n].x - p.xpos,
    631  1.25  dholland 			sp->airport[n].y - p.ypos);
    632   1.1       cgd 		break;
    633   1.1       cgd 	default:
    634   1.1       cgd 		return ("Unknown case in benum!  Get help!");
    635   1.1       cgd 	}
    636   1.1       cgd 	return (NULL);
    637   1.1       cgd }
    638   1.1       cgd 
    639  1.24  dholland static const char *
    640  1.18       jmc to_dir(int c)
    641   1.1       cgd {
    642   1.1       cgd 	p.new_dir = dir_no(c);
    643   1.1       cgd 	return (NULL);
    644   1.1       cgd }
    645   1.1       cgd 
    646  1.24  dholland static const char *
    647  1.18       jmc rel_dir(int c)
    648   1.1       cgd {
    649   1.1       cgd 	int	angle;
    650   1.1       cgd 
    651   1.1       cgd 	angle = dir_no(c);
    652   1.1       cgd 	switch (dir) {
    653   1.1       cgd 	case D_LEFT:
    654   1.1       cgd 		p.new_dir = p.dir - angle;
    655   1.1       cgd 		if (p.new_dir < 0)
    656   1.1       cgd 			p.new_dir += MAXDIR;
    657   1.1       cgd 		break;
    658   1.1       cgd 	case D_RIGHT:
    659   1.1       cgd 		p.new_dir = p.dir + angle;
    660   1.1       cgd 		if (p.new_dir >= MAXDIR)
    661   1.1       cgd 			p.new_dir -= MAXDIR;
    662   1.1       cgd 		break;
    663   1.1       cgd 	default:
    664   1.1       cgd 		return ("Bizarre direction in rel_dir!  Get help!");
    665   1.1       cgd 	}
    666   1.1       cgd 	return (NULL);
    667   1.1       cgd }
    668   1.1       cgd 
    669  1.19    rpaulo /* ARGSUSED */
    670  1.24  dholland static const char *
    671  1.22     perry mark(int c __unused)
    672   1.1       cgd {
    673   1.1       cgd 	if (p.altitude == 0)
    674   1.1       cgd 		return ("Cannot mark planes on the ground");
    675   1.1       cgd 	if (p.status == S_MARKED)
    676   1.1       cgd 		return ("Already marked");
    677   1.1       cgd 	p.status = S_MARKED;
    678   1.1       cgd 	return (NULL);
    679   1.1       cgd }
    680   1.1       cgd 
    681  1.19    rpaulo /* ARGSUSED */
    682  1.24  dholland static const char *
    683  1.22     perry unmark(int c __unused)
    684   1.1       cgd {
    685   1.1       cgd 	if (p.altitude == 0)
    686   1.1       cgd 		return ("Cannot unmark planes on the ground");
    687   1.1       cgd 	if (p.status == S_UNMARKED)
    688   1.1       cgd 		return ("Already unmarked");
    689   1.1       cgd 	p.status = S_UNMARKED;
    690   1.1       cgd 	return (NULL);
    691   1.1       cgd }
    692   1.1       cgd 
    693  1.19    rpaulo /* ARGSUSED */
    694  1.24  dholland static const char *
    695  1.22     perry ignore(int c __unused)
    696   1.1       cgd {
    697   1.1       cgd 	if (p.altitude == 0)
    698   1.1       cgd 		return ("Cannot ignore planes on the ground");
    699   1.1       cgd 	if (p.status == S_IGNORED)
    700   1.1       cgd 		return ("Already ignored");
    701   1.1       cgd 	p.status = S_IGNORED;
    702   1.1       cgd 	return (NULL);
    703   1.1       cgd }
    704   1.1       cgd 
    705   1.6     lukem int
    706  1.18       jmc dir_no(int ch)
    707   1.1       cgd {
    708  1.18       jmc 	int	dirno;
    709   1.1       cgd 
    710  1.18       jmc 	dirno = -1;
    711   1.1       cgd 	switch (ch) {
    712  1.18       jmc 	case 'w':	dirno = 0;	break;
    713  1.18       jmc 	case 'e':	dirno = 1;	break;
    714  1.18       jmc 	case 'd':	dirno = 2;	break;
    715  1.18       jmc 	case 'c':	dirno = 3;	break;
    716  1.18       jmc 	case 'x':	dirno = 4;	break;
    717  1.18       jmc 	case 'z':	dirno = 5;	break;
    718  1.18       jmc 	case 'a':	dirno = 6;	break;
    719  1.18       jmc 	case 'q':	dirno = 7;	break;
    720   1.1       cgd 	default:
    721  1.19    rpaulo 		(void)fprintf(stderr, "bad character in dir_no\n");
    722   1.1       cgd 		break;
    723   1.1       cgd 	}
    724  1.18       jmc 	return (dirno);
    725   1.1       cgd }
    726