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input.c revision 1.14
      1  1.14      cgd /*	$NetBSD: input.c,v 1.14 2001/01/16 02:50:28 cgd 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   1.1      cgd  * 3. All advertising materials mentioning features or use of this software
     19   1.1      cgd  *    must display the following acknowledgement:
     20   1.1      cgd  *	This product includes software developed by the University of
     21   1.1      cgd  *	California, Berkeley and its contributors.
     22   1.1      cgd  * 4. Neither the name of the University nor the names of its contributors
     23   1.1      cgd  *    may be used to endorse or promote products derived from this software
     24   1.1      cgd  *    without specific prior written permission.
     25   1.1      cgd  *
     26   1.1      cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27   1.1      cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28   1.1      cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29   1.1      cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30   1.1      cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31   1.1      cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32   1.1      cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33   1.1      cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34   1.1      cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35   1.1      cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36   1.1      cgd  * SUCH DAMAGE.
     37   1.1      cgd  */
     38   1.1      cgd 
     39   1.1      cgd /*
     40   1.1      cgd  * Copyright (c) 1987 by Ed James, UC Berkeley.  All rights reserved.
     41   1.1      cgd  *
     42   1.1      cgd  * Copy permission is hereby granted provided that this notice is
     43   1.1      cgd  * retained on all partial or complete copies.
     44   1.1      cgd  *
     45   1.1      cgd  * For more info on this and all of my stuff, mail edjames (at) berkeley.edu.
     46   1.1      cgd  */
     47   1.1      cgd 
     48   1.6    lukem #include <sys/cdefs.h>
     49   1.1      cgd #ifndef lint
     50   1.3      cgd #if 0
     51   1.3      cgd static char sccsid[] = "@(#)input.c	8.1 (Berkeley) 5/31/93";
     52   1.3      cgd #else
     53  1.14      cgd __RCSID("$NetBSD: input.c,v 1.14 2001/01/16 02:50:28 cgd Exp $");
     54   1.3      cgd #endif
     55  1.14      cgd #endif /* not lint */
     56   1.1      cgd 
     57   1.1      cgd #include "include.h"
     58   1.1      cgd #include "pathnames.h"
     59   1.1      cgd 
     60   1.1      cgd #define MAXRULES	6
     61   1.1      cgd #define MAXDEPTH	15
     62   1.1      cgd 
     63   1.1      cgd #define RETTOKEN	'\n'
     64   1.1      cgd #define REDRAWTOKEN	'\014'	/* CTRL(L) */
     65   1.1      cgd #define	SHELLTOKEN	'!'
     66   1.1      cgd #define HELPTOKEN	'?'
     67   1.1      cgd #define ALPHATOKEN	256
     68   1.1      cgd #define NUMTOKEN	257
     69   1.1      cgd 
     70   1.1      cgd typedef struct {
     71   1.1      cgd 	int	token;
     72   1.1      cgd 	int	to_state;
     73  1.11  hubertf 	const char	*str;
     74  1.11  hubertf 	const char	*(*func) __P((char));
     75   1.1      cgd } RULE;
     76   1.1      cgd 
     77   1.1      cgd typedef struct {
     78   1.1      cgd 	int	num_rules;
     79   1.1      cgd 	RULE	*rule;
     80   1.1      cgd } STATE;
     81   1.1      cgd 
     82   1.1      cgd typedef struct {
     83   1.1      cgd 	char	str[20];
     84   1.1      cgd 	int	state;
     85   1.1      cgd 	int	rule;
     86   1.1      cgd 	int	ch;
     87   1.1      cgd 	int	pos;
     88   1.1      cgd } STACK;
     89   1.1      cgd 
     90   1.1      cgd #define T_RULE		stack[level].rule
     91   1.1      cgd #define T_STATE		stack[level].state
     92   1.1      cgd #define T_STR		stack[level].str
     93   1.1      cgd #define T_POS		stack[level].pos
     94   1.1      cgd #define	T_CH		stack[level].ch
     95   1.1      cgd 
     96   1.1      cgd #define NUMELS(a)	(sizeof (a) / sizeof (*(a)))
     97   1.1      cgd 
     98   1.1      cgd #define NUMSTATES	NUMELS(st)
     99   1.1      cgd 
    100   1.1      cgd 
    101   1.1      cgd RULE	state0[] = {	{ ALPHATOKEN,	1,	"%c:",		setplane},
    102   1.1      cgd 			{ RETTOKEN,	-1,	"",		NULL	},
    103   1.1      cgd 			{ HELPTOKEN,	12,	" [a-z]<ret>",	NULL	}},
    104   1.1      cgd 	state1[] = {	{ 't',		2,	" turn",	turn	},
    105   1.1      cgd 			{ 'a',		3,	" altitude:",	NULL	},
    106   1.1      cgd 			{ 'c',		4,	" circle",	circle	},
    107   1.1      cgd 			{ 'm',		7,	" mark",	mark	},
    108   1.1      cgd 			{ 'u',		7,	" unmark",	unmark	},
    109   1.1      cgd 			{ 'i',		7,	" ignore",	ignore	},
    110   1.1      cgd 			{ HELPTOKEN,	12,	" tacmui",	NULL	}},
    111   1.1      cgd 	state2[] = {	{ 'l',		6,	" left",	left	},
    112   1.1      cgd 			{ 'r',		6,	" right",	right	},
    113   1.1      cgd 			{ 'L',		4,	" left 90",	Left	},
    114   1.1      cgd 			{ 'R',		4,	" right 90",	Right	},
    115   1.1      cgd 			{ 't',		11,	" towards",	NULL	},
    116   1.1      cgd 			{ 'w',		4,	" to 0",	to_dir	},
    117   1.1      cgd 			{ 'e',		4,	" to 45",	to_dir	},
    118   1.1      cgd 			{ 'd',		4,	" to 90",	to_dir	},
    119   1.1      cgd 			{ 'c',		4,	" to 135",	to_dir	},
    120   1.1      cgd 			{ 'x',		4,	" to 180",	to_dir	},
    121   1.1      cgd 			{ 'z',		4,	" to 225",	to_dir	},
    122   1.1      cgd 			{ 'a',		4,	" to 270",	to_dir	},
    123   1.1      cgd 			{ 'q',		4,	" to 315",	to_dir	},
    124   1.1      cgd 			{ HELPTOKEN,	12,	" lrLRt<dir>",	NULL	}},
    125   1.1      cgd 	state3[] = {	{ '+',		10,	" climb",	climb	},
    126   1.1      cgd 			{ 'c',		10,	" climb",	climb	},
    127   1.1      cgd 			{ '-',		10,	" descend",	descend	},
    128   1.1      cgd 			{ 'd',		10,	" descend",	descend	},
    129   1.1      cgd 			{ NUMTOKEN,	7,	" %c000 feet",	setalt	},
    130   1.1      cgd 			{ HELPTOKEN,	12,	" +-cd[0-9]",	NULL	}},
    131   1.1      cgd 	state4[] = {	{ '@',		9,	" at",		NULL	},
    132   1.1      cgd 			{ 'a',		9,	" at",		NULL	},
    133   1.1      cgd 			{ RETTOKEN,	-1,	"",		NULL	},
    134   1.1      cgd 			{ HELPTOKEN,	12,	" @a<ret>",	NULL	}},
    135   1.1      cgd 	state5[] = {	{ NUMTOKEN,	7,	"%c",		delayb	},
    136   1.1      cgd 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    137   1.1      cgd 	state6[] = {	{ '@',		9,	" at",		NULL	},
    138   1.1      cgd 			{ 'a',		9,	" at",		NULL	},
    139   1.1      cgd 			{ 'w',		4,	" 0",		rel_dir	},
    140   1.1      cgd 			{ 'e',		4,	" 45",		rel_dir	},
    141   1.1      cgd 			{ 'd',		4,	" 90",		rel_dir	},
    142   1.1      cgd 			{ 'c',		4,	" 135",		rel_dir	},
    143   1.1      cgd 			{ 'x',		4,	" 180",		rel_dir	},
    144   1.1      cgd 			{ 'z',		4,	" 225",		rel_dir	},
    145   1.1      cgd 			{ 'a',		4,	" 270",		rel_dir	},
    146   1.1      cgd 			{ 'q',		4,	" 315",		rel_dir	},
    147   1.1      cgd 			{ RETTOKEN,	-1,	"",		NULL	},
    148   1.1      cgd 			{ HELPTOKEN,	12,	" @a<dir><ret>",NULL	}},
    149   1.1      cgd 	state7[] = {	{ RETTOKEN,	-1,	"",		NULL	},
    150   1.1      cgd 			{ HELPTOKEN,	12,	" <ret>",	NULL	}},
    151   1.1      cgd 	state8[] = {	{ NUMTOKEN,	4,	"%c",		benum	},
    152   1.1      cgd 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    153   1.1      cgd 	state9[] = {	{ 'b',		5,	" beacon #",	NULL	},
    154   1.1      cgd 			{ '*',		5,	" beacon #",	NULL	},
    155   1.1      cgd 			{ HELPTOKEN,	12,	" b*",		NULL	}},
    156   1.1      cgd 	state10[] = {	{ NUMTOKEN,	7,	" %c000 ft",	setrelalt},
    157   1.1      cgd 			{ HELPTOKEN,	12,	" [0-9]",	NULL	}},
    158   1.1      cgd 	state11[] = {	{ 'b',		8,	" beacon #",	beacon	},
    159   1.1      cgd 			{ '*',		8,	" beacon #",	beacon	},
    160   1.1      cgd 			{ 'e',		8,	" exit #",	ex_it	},
    161   1.1      cgd 			{ 'a',		8,	" airport #",	airport	},
    162   1.1      cgd 			{ HELPTOKEN,	12,	" b*ea",	NULL	}},
    163   1.1      cgd 	state12[] = {	{ -1,		-1,	"",		NULL	}};
    164   1.1      cgd 
    165   1.1      cgd #define DEF_STATE(s)	{ NUMELS(s),	(s)	}
    166   1.1      cgd 
    167   1.1      cgd STATE	st[] = {
    168   1.1      cgd 	DEF_STATE(state0), DEF_STATE(state1), DEF_STATE(state2),
    169   1.1      cgd 	DEF_STATE(state3), DEF_STATE(state4), DEF_STATE(state5),
    170   1.1      cgd 	DEF_STATE(state6), DEF_STATE(state7), DEF_STATE(state8),
    171   1.1      cgd 	DEF_STATE(state9), DEF_STATE(state10), DEF_STATE(state11),
    172   1.1      cgd 	DEF_STATE(state12)
    173   1.1      cgd };
    174   1.1      cgd 
    175   1.1      cgd PLANE	p;
    176   1.1      cgd STACK	stack[MAXDEPTH];
    177   1.1      cgd int	level;
    178   1.1      cgd int	tval;
    179   1.1      cgd int	dest_type, dest_no, dir;
    180   1.1      cgd 
    181   1.6    lukem int
    182   1.1      cgd pop()
    183   1.1      cgd {
    184   1.1      cgd 	if (level == 0)
    185   1.1      cgd 		return (-1);
    186   1.1      cgd 	level--;
    187   1.1      cgd 
    188   1.1      cgd 	ioclrtoeol(T_POS);
    189   1.1      cgd 
    190   1.1      cgd 	strcpy(T_STR, "");
    191   1.1      cgd 	T_RULE = -1;
    192   1.1      cgd 	T_CH = -1;
    193   1.1      cgd 	return (0);
    194   1.1      cgd }
    195   1.1      cgd 
    196   1.6    lukem void
    197   1.1      cgd rezero()
    198   1.1      cgd {
    199   1.1      cgd 	iomove(0);
    200   1.1      cgd 
    201   1.1      cgd 	level = 0;
    202   1.1      cgd 	T_STATE = 0;
    203   1.1      cgd 	T_RULE = -1;
    204   1.1      cgd 	T_CH = -1;
    205   1.1      cgd 	T_POS = 0;
    206   1.1      cgd 	strcpy(T_STR, "");
    207   1.1      cgd }
    208   1.1      cgd 
    209   1.6    lukem void
    210   1.1      cgd push(ruleno, ch)
    211   1.6    lukem 	int ruleno, ch;
    212   1.1      cgd {
    213   1.1      cgd 	int	newstate, newpos;
    214   1.1      cgd 
    215   1.1      cgd 	(void)sprintf(T_STR, st[T_STATE].rule[ruleno].str, tval);
    216   1.1      cgd 	T_RULE = ruleno;
    217   1.1      cgd 	T_CH = ch;
    218   1.1      cgd 	newstate = st[T_STATE].rule[ruleno].to_state;
    219   1.1      cgd 	newpos = T_POS + strlen(T_STR);
    220   1.1      cgd 
    221   1.1      cgd 	ioaddstr(T_POS, T_STR);
    222   1.1      cgd 
    223   1.1      cgd 	if (level == 0)
    224   1.1      cgd 		ioclrtobot();
    225   1.1      cgd 	level++;
    226   1.1      cgd 	T_STATE = newstate;
    227   1.1      cgd 	T_POS = newpos;
    228   1.1      cgd 	T_RULE = -1;
    229   1.1      cgd 	strcpy(T_STR, "");
    230   1.1      cgd }
    231   1.1      cgd 
    232   1.6    lukem int
    233   1.1      cgd getcommand()
    234   1.1      cgd {
    235   1.1      cgd 	int	c, i, done;
    236  1.11  hubertf 	const char	*s, *(*func) __P((char));
    237   1.1      cgd 	PLANE	*pp;
    238   1.1      cgd 
    239   1.1      cgd 	rezero();
    240   1.1      cgd 
    241   1.1      cgd 	do {
    242   1.1      cgd 		c = gettoken();
    243   1.4  mycroft 		if (c == tty_new.c_cc[VERASE]) {
    244   1.1      cgd 			if (pop() < 0)
    245   1.1      cgd 				noise();
    246   1.4  mycroft 		} else if (c == tty_new.c_cc[VKILL]) {
    247   1.1      cgd 			while (pop() >= 0)
    248   1.1      cgd 				;
    249   1.1      cgd 		} else {
    250   1.1      cgd 			done = 0;
    251   1.1      cgd 			for (i = 0; i < st[T_STATE].num_rules; i++) {
    252   1.1      cgd 				if (st[T_STATE].rule[i].token == c ||
    253   1.1      cgd 				    st[T_STATE].rule[i].token == tval) {
    254   1.1      cgd 					push(i, (c >= ALPHATOKEN) ? tval : c);
    255   1.1      cgd 					done = 1;
    256   1.1      cgd 					break;
    257   1.1      cgd 				}
    258   1.1      cgd 			}
    259   1.1      cgd 			if (!done)
    260   1.1      cgd 				noise();
    261   1.1      cgd 		}
    262   1.1      cgd 	} while (T_STATE != -1);
    263   1.1      cgd 
    264   1.1      cgd 	if (level == 1)
    265   1.1      cgd 		return (1);	/* forced update */
    266   1.1      cgd 
    267   1.1      cgd 	dest_type = T_NODEST;
    268   1.1      cgd 
    269   1.1      cgd 	for (i = 0; i < level; i++) {
    270   1.1      cgd 		func = st[stack[i].state].rule[stack[i].rule].func;
    271   1.1      cgd 		if (func != NULL)
    272   1.1      cgd 			if ((s = (*func)(stack[i].ch)) != NULL) {
    273   1.1      cgd 				ioerror(stack[i].pos, strlen(stack[i].str), s);
    274   1.1      cgd 				return (-1);
    275   1.1      cgd 			}
    276   1.1      cgd 	}
    277   1.1      cgd 
    278   1.1      cgd 	pp = findplane(p.plane_no);
    279   1.1      cgd 	if (pp->new_altitude != p.new_altitude)
    280   1.1      cgd 		pp->new_altitude = p.new_altitude;
    281   1.1      cgd 	else if (pp->status != p.status)
    282   1.1      cgd 		pp->status = p.status;
    283   1.1      cgd 	else {
    284   1.1      cgd 		pp->new_dir = p.new_dir;
    285   1.1      cgd 		pp->delayd = p.delayd;
    286   1.1      cgd 		pp->delayd_no = p.delayd_no;
    287   1.1      cgd 	}
    288   1.1      cgd 	return (0);
    289   1.1      cgd }
    290   1.1      cgd 
    291   1.6    lukem void
    292   1.1      cgd noise()
    293   1.1      cgd {
    294   1.1      cgd 	putchar('\07');
    295   1.1      cgd 	fflush(stdout);
    296   1.1      cgd }
    297   1.1      cgd 
    298   1.6    lukem int
    299   1.1      cgd gettoken()
    300   1.1      cgd {
    301   1.1      cgd 	while ((tval = getAChar()) == REDRAWTOKEN || tval == SHELLTOKEN)
    302   1.1      cgd 	{
    303   1.1      cgd 		if (tval == SHELLTOKEN)
    304   1.1      cgd 		{
    305   1.1      cgd #ifdef BSD
    306   1.1      cgd 			struct itimerval	itv;
    307   1.1      cgd 			itv.it_value.tv_sec = 0;
    308   1.1      cgd 			itv.it_value.tv_usec = 0;
    309   1.1      cgd 			setitimer(ITIMER_REAL, &itv, NULL);
    310   1.1      cgd #endif
    311   1.1      cgd #ifdef SYSV
    312   1.1      cgd 			int aval;
    313   1.1      cgd 			aval = alarm(0);
    314   1.1      cgd #endif
    315   1.1      cgd 			if (fork() == 0)	/* child */
    316   1.1      cgd 			{
    317   1.6    lukem 				char *shell, *base;
    318   1.1      cgd 
    319   1.1      cgd 				done_screen();
    320   1.1      cgd 
    321   1.1      cgd 						 /* run user's favorite shell */
    322   1.1      cgd 				if ((shell = getenv("SHELL")) != NULL)
    323   1.1      cgd 				{
    324   1.1      cgd 					base = strrchr(shell, '/');
    325   1.1      cgd 					if (base == NULL)
    326   1.1      cgd 						base = shell;
    327   1.1      cgd 					else
    328   1.1      cgd 						base++;
    329   1.1      cgd 					execl(shell, base, 0);
    330   1.1      cgd 				}
    331   1.1      cgd 				else
    332   1.1      cgd 					execl(_PATH_BSHELL, "sh", 0);
    333   1.1      cgd 
    334   1.1      cgd 				exit(0);	/* oops */
    335   1.1      cgd 			}
    336   1.1      cgd 
    337   1.1      cgd 			wait(0);
    338   1.4  mycroft 			tcsetattr(fileno(stdin), TCSADRAIN, &tty_new);
    339   1.1      cgd #ifdef BSD
    340   1.1      cgd 			itv.it_value.tv_sec = 0;
    341   1.1      cgd 			itv.it_value.tv_usec = 1;
    342   1.1      cgd 			itv.it_interval.tv_sec = sp->update_secs;
    343   1.1      cgd 			itv.it_interval.tv_usec = 0;
    344   1.1      cgd 			setitimer(ITIMER_REAL, &itv, NULL);
    345   1.1      cgd #endif
    346   1.1      cgd #ifdef SYSV
    347   1.1      cgd 			alarm(aval);
    348   1.1      cgd #endif
    349   1.1      cgd 		}
    350   1.1      cgd 		redraw();
    351   1.1      cgd 	}
    352   1.1      cgd 
    353   1.1      cgd 	if (isdigit(tval))
    354   1.1      cgd 		return (NUMTOKEN);
    355   1.1      cgd 	else if (isalpha(tval))
    356   1.1      cgd 		return (ALPHATOKEN);
    357   1.1      cgd 	else
    358   1.1      cgd 		return (tval);
    359   1.1      cgd }
    360   1.1      cgd 
    361  1.11  hubertf const char	*
    362   1.1      cgd setplane(c)
    363   1.6    lukem 	char c;
    364   1.1      cgd {
    365   1.1      cgd 	PLANE	*pp;
    366   1.1      cgd 
    367   1.1      cgd 	pp = findplane(number(c));
    368   1.1      cgd 	if (pp == NULL)
    369   1.1      cgd 		return ("Unknown Plane");
    370   1.5      tls 	memcpy(&p, pp, sizeof (p));
    371   1.1      cgd 	p.delayd = 0;
    372   1.1      cgd 	return (NULL);
    373   1.1      cgd }
    374   1.1      cgd 
    375  1.11  hubertf const char	*
    376   1.1      cgd turn(c)
    377  1.13  hubertf 	char c __attribute__((__unused__));
    378   1.1      cgd {
    379   1.1      cgd 	if (p.altitude == 0)
    380   1.1      cgd 		return ("Planes at airports may not change direction");
    381   1.1      cgd 	return (NULL);
    382   1.1      cgd }
    383   1.1      cgd 
    384  1.11  hubertf const char	*
    385   1.1      cgd circle(c)
    386  1.13  hubertf 	char c __attribute__((__unused__));
    387   1.1      cgd {
    388   1.1      cgd 	if (p.altitude == 0)
    389   1.1      cgd 		return ("Planes cannot circle on the ground");
    390   1.1      cgd 	p.new_dir = MAXDIR;
    391   1.1      cgd 	return (NULL);
    392   1.1      cgd }
    393   1.1      cgd 
    394  1.11  hubertf const char	*
    395   1.1      cgd left(c)
    396  1.13  hubertf 	char c __attribute__((__unused__));
    397   1.1      cgd {
    398   1.1      cgd 	dir = D_LEFT;
    399   1.1      cgd 	p.new_dir = p.dir - 1;
    400   1.1      cgd 	if (p.new_dir < 0)
    401   1.1      cgd 		p.new_dir += MAXDIR;
    402   1.1      cgd 	return (NULL);
    403   1.1      cgd }
    404   1.1      cgd 
    405  1.11  hubertf const char	*
    406   1.1      cgd right(c)
    407  1.13  hubertf 	char c __attribute__((__unused__));
    408   1.1      cgd {
    409   1.1      cgd 	dir = D_RIGHT;
    410   1.1      cgd 	p.new_dir = p.dir + 1;
    411   1.9   briggs 	if (p.new_dir >= MAXDIR)
    412   1.1      cgd 		p.new_dir -= MAXDIR;
    413   1.1      cgd 	return (NULL);
    414   1.1      cgd }
    415   1.1      cgd 
    416  1.11  hubertf const char	*
    417   1.1      cgd Left(c)
    418  1.13  hubertf 	char c __attribute__((__unused__));
    419   1.1      cgd {
    420   1.1      cgd 	p.new_dir = p.dir - 2;
    421   1.1      cgd 	if (p.new_dir < 0)
    422   1.1      cgd 		p.new_dir += MAXDIR;
    423   1.1      cgd 	return (NULL);
    424   1.1      cgd }
    425   1.1      cgd 
    426  1.11  hubertf const char	*
    427   1.1      cgd Right(c)
    428  1.13  hubertf 	char c __attribute__((__unused__));
    429   1.1      cgd {
    430   1.1      cgd 	p.new_dir = p.dir + 2;
    431   1.8   briggs 	if (p.new_dir >= MAXDIR)
    432   1.1      cgd 		p.new_dir -= MAXDIR;
    433   1.1      cgd 	return (NULL);
    434   1.1      cgd }
    435   1.1      cgd 
    436  1.11  hubertf const char	*
    437   1.1      cgd delayb(c)
    438   1.6    lukem 	char c;
    439   1.1      cgd {
    440   1.1      cgd 	int	xdiff, ydiff;
    441   1.1      cgd 
    442   1.1      cgd 	c -= '0';
    443   1.1      cgd 
    444   1.1      cgd 	if (c >= sp->num_beacons)
    445   1.1      cgd 		return ("Unknown beacon");
    446   1.7      mrg 	xdiff = sp->beacon[(int)c].x - p.xpos;
    447   1.1      cgd 	xdiff = SGN(xdiff);
    448   1.7      mrg 	ydiff = sp->beacon[(int)c].y - p.ypos;
    449   1.1      cgd 	ydiff = SGN(ydiff);
    450   1.1      cgd 	if (xdiff != displacement[p.dir].dx || ydiff != displacement[p.dir].dy)
    451   1.1      cgd 		return ("Beacon is not in flight path");
    452   1.1      cgd 	p.delayd = 1;
    453   1.1      cgd 	p.delayd_no = c;
    454   1.1      cgd 
    455   1.1      cgd 	if (dest_type != T_NODEST) {
    456   1.1      cgd 		switch (dest_type) {
    457   1.1      cgd 		case T_BEACON:
    458   1.7      mrg 			xdiff = sp->beacon[dest_no].x - sp->beacon[(int)c].x;
    459   1.7      mrg 			ydiff = sp->beacon[dest_no].y - sp->beacon[(int)c].y;
    460   1.1      cgd 			break;
    461   1.1      cgd 		case T_EXIT:
    462   1.7      mrg 			xdiff = sp->exit[dest_no].x - sp->beacon[(int)c].x;
    463   1.7      mrg 			ydiff = sp->exit[dest_no].y - sp->beacon[(int)c].y;
    464   1.1      cgd 			break;
    465   1.1      cgd 		case T_AIRPORT:
    466   1.7      mrg 			xdiff = sp->airport[dest_no].x - sp->beacon[(int)c].x;
    467   1.7      mrg 			ydiff = sp->airport[dest_no].y - sp->beacon[(int)c].y;
    468   1.1      cgd 			break;
    469   1.1      cgd 		default:
    470   1.1      cgd 			return ("Bad case in delayb!  Get help!");
    471   1.1      cgd 			break;
    472   1.1      cgd 		}
    473   1.1      cgd 		if (xdiff == 0 && ydiff == 0)
    474   1.1      cgd 			return ("Would already be there");
    475   1.1      cgd 		p.new_dir = DIR_FROM_DXDY(xdiff, ydiff);
    476   1.1      cgd 		if (p.new_dir == p.dir)
    477   1.1      cgd 			return ("Already going in that direction");
    478   1.1      cgd 	}
    479   1.1      cgd 	return (NULL);
    480   1.1      cgd }
    481   1.1      cgd 
    482  1.11  hubertf const char	*
    483   1.1      cgd beacon(c)
    484  1.13  hubertf 	char c __attribute__((__unused__));
    485   1.1      cgd {
    486   1.1      cgd 	dest_type = T_BEACON;
    487   1.1      cgd 	return (NULL);
    488   1.1      cgd }
    489   1.1      cgd 
    490  1.11  hubertf const char	*
    491   1.1      cgd ex_it(c)
    492  1.13  hubertf 	char c __attribute__((__unused__));
    493   1.1      cgd {
    494   1.1      cgd 	dest_type = T_EXIT;
    495   1.1      cgd 	return (NULL);
    496   1.1      cgd }
    497   1.1      cgd 
    498  1.11  hubertf const char	*
    499   1.1      cgd airport(c)
    500  1.13  hubertf 	char c __attribute__((__unused__));
    501   1.1      cgd {
    502   1.1      cgd 	dest_type = T_AIRPORT;
    503   1.1      cgd 	return (NULL);
    504   1.1      cgd }
    505   1.1      cgd 
    506  1.11  hubertf const char	*
    507   1.1      cgd climb(c)
    508  1.13  hubertf 	char c __attribute__((__unused__));
    509   1.1      cgd {
    510   1.1      cgd 	dir = D_UP;
    511   1.1      cgd 	return (NULL);
    512   1.1      cgd }
    513   1.1      cgd 
    514  1.11  hubertf const char	*
    515   1.1      cgd descend(c)
    516  1.13  hubertf 	char c __attribute__((__unused__));
    517   1.1      cgd {
    518   1.1      cgd 	dir = D_DOWN;
    519   1.1      cgd 	return (NULL);
    520   1.1      cgd }
    521   1.1      cgd 
    522  1.11  hubertf const char	*
    523   1.1      cgd setalt(c)
    524   1.6    lukem 	char c;
    525   1.1      cgd {
    526   1.1      cgd 	if ((p.altitude == c - '0') && (p.new_altitude == p.altitude))
    527   1.1      cgd 		return ("Already at that altitude");
    528   1.1      cgd 	p.new_altitude = c - '0';
    529   1.1      cgd 	return (NULL);
    530   1.1      cgd }
    531   1.1      cgd 
    532  1.11  hubertf const char	*
    533   1.1      cgd setrelalt(c)
    534   1.6    lukem 	char c;
    535   1.1      cgd {
    536   1.1      cgd 	if (c == 0)
    537   1.1      cgd 		return ("altitude not changed");
    538   1.1      cgd 
    539   1.1      cgd 	switch (dir) {
    540   1.1      cgd 	case D_UP:
    541   1.1      cgd 		p.new_altitude = p.altitude + c - '0';
    542   1.1      cgd 		break;
    543   1.1      cgd 	case D_DOWN:
    544   1.1      cgd 		p.new_altitude = p.altitude - (c - '0');
    545   1.1      cgd 		break;
    546   1.1      cgd 	default:
    547   1.1      cgd 		return ("Unknown case in setrelalt!  Get help!");
    548   1.1      cgd 		break;
    549   1.1      cgd 	}
    550   1.1      cgd 	if (p.new_altitude < 0)
    551   1.1      cgd 		return ("Altitude would be too low");
    552   1.1      cgd 	else if (p.new_altitude > 9)
    553   1.1      cgd 		return ("Altitude would be too high");
    554   1.1      cgd 	return (NULL);
    555   1.1      cgd }
    556   1.1      cgd 
    557  1.11  hubertf const char	*
    558   1.1      cgd benum(c)
    559   1.6    lukem 	char c;
    560   1.1      cgd {
    561   1.1      cgd 	dest_no = c -= '0';
    562   1.1      cgd 
    563   1.1      cgd 	switch (dest_type) {
    564   1.1      cgd 	case T_BEACON:
    565   1.1      cgd 		if (c >= sp->num_beacons)
    566   1.1      cgd 			return ("Unknown beacon");
    567   1.7      mrg 		p.new_dir = DIR_FROM_DXDY(sp->beacon[(int)c].x - p.xpos,
    568   1.7      mrg 			sp->beacon[(int)c].y - p.ypos);
    569   1.1      cgd 		break;
    570   1.1      cgd 	case T_EXIT:
    571   1.1      cgd 		if (c >= sp->num_exits)
    572   1.1      cgd 			return ("Unknown exit");
    573   1.7      mrg 		p.new_dir = DIR_FROM_DXDY(sp->exit[(int)c].x - p.xpos,
    574   1.7      mrg 			sp->exit[(int)c].y - p.ypos);
    575   1.1      cgd 		break;
    576   1.1      cgd 	case T_AIRPORT:
    577   1.1      cgd 		if (c >= sp->num_airports)
    578   1.1      cgd 			return ("Unknown airport");
    579   1.7      mrg 		p.new_dir = DIR_FROM_DXDY(sp->airport[(int)c].x - p.xpos,
    580   1.7      mrg 			sp->airport[(int)c].y - p.ypos);
    581   1.1      cgd 		break;
    582   1.1      cgd 	default:
    583   1.1      cgd 		return ("Unknown case in benum!  Get help!");
    584   1.1      cgd 		break;
    585   1.1      cgd 	}
    586   1.1      cgd 	return (NULL);
    587   1.1      cgd }
    588   1.1      cgd 
    589  1.11  hubertf const char	*
    590   1.1      cgd to_dir(c)
    591   1.6    lukem 	char c;
    592   1.1      cgd {
    593   1.1      cgd 	p.new_dir = dir_no(c);
    594   1.1      cgd 	return (NULL);
    595   1.1      cgd }
    596   1.1      cgd 
    597  1.11  hubertf const char	*
    598   1.1      cgd rel_dir(c)
    599   1.6    lukem 	char c;
    600   1.1      cgd {
    601   1.1      cgd 	int	angle;
    602   1.1      cgd 
    603   1.1      cgd 	angle = dir_no(c);
    604   1.1      cgd 	switch (dir) {
    605   1.1      cgd 	case D_LEFT:
    606   1.1      cgd 		p.new_dir = p.dir - angle;
    607   1.1      cgd 		if (p.new_dir < 0)
    608   1.1      cgd 			p.new_dir += MAXDIR;
    609   1.1      cgd 		break;
    610   1.1      cgd 	case D_RIGHT:
    611   1.1      cgd 		p.new_dir = p.dir + angle;
    612   1.1      cgd 		if (p.new_dir >= MAXDIR)
    613   1.1      cgd 			p.new_dir -= MAXDIR;
    614   1.1      cgd 		break;
    615   1.1      cgd 	default:
    616   1.1      cgd 		return ("Bizarre direction in rel_dir!  Get help!");
    617   1.1      cgd 		break;
    618   1.1      cgd 	}
    619   1.1      cgd 	return (NULL);
    620   1.1      cgd }
    621   1.1      cgd 
    622  1.11  hubertf const char	*
    623   1.1      cgd mark(c)
    624  1.13  hubertf 	char c __attribute__((__unused__));
    625   1.1      cgd {
    626   1.1      cgd 	if (p.altitude == 0)
    627   1.1      cgd 		return ("Cannot mark planes on the ground");
    628   1.1      cgd 	if (p.status == S_MARKED)
    629   1.1      cgd 		return ("Already marked");
    630   1.1      cgd 	p.status = S_MARKED;
    631   1.1      cgd 	return (NULL);
    632   1.1      cgd }
    633   1.1      cgd 
    634  1.11  hubertf const char	*
    635   1.1      cgd unmark(c)
    636  1.13  hubertf 	char c __attribute__((__unused__));
    637   1.1      cgd {
    638   1.1      cgd 	if (p.altitude == 0)
    639   1.1      cgd 		return ("Cannot unmark planes on the ground");
    640   1.1      cgd 	if (p.status == S_UNMARKED)
    641   1.1      cgd 		return ("Already unmarked");
    642   1.1      cgd 	p.status = S_UNMARKED;
    643   1.1      cgd 	return (NULL);
    644   1.1      cgd }
    645   1.1      cgd 
    646  1.11  hubertf const char	*
    647   1.1      cgd ignore(c)
    648  1.13  hubertf 	char c __attribute__((__unused__));
    649   1.1      cgd {
    650   1.1      cgd 	if (p.altitude == 0)
    651   1.1      cgd 		return ("Cannot ignore planes on the ground");
    652   1.1      cgd 	if (p.status == S_IGNORED)
    653   1.1      cgd 		return ("Already ignored");
    654   1.1      cgd 	p.status = S_IGNORED;
    655   1.1      cgd 	return (NULL);
    656   1.1      cgd }
    657   1.1      cgd 
    658   1.6    lukem int
    659   1.1      cgd dir_no(ch)
    660   1.1      cgd 	char	ch;
    661   1.1      cgd {
    662   1.1      cgd 	int	dir;
    663   1.1      cgd 
    664   1.6    lukem 	dir = -1;
    665   1.1      cgd 	switch (ch) {
    666   1.1      cgd 	case 'w':	dir = 0;	break;
    667   1.1      cgd 	case 'e':	dir = 1;	break;
    668   1.1      cgd 	case 'd':	dir = 2;	break;
    669   1.1      cgd 	case 'c':	dir = 3;	break;
    670   1.1      cgd 	case 'x':	dir = 4;	break;
    671   1.1      cgd 	case 'z':	dir = 5;	break;
    672   1.1      cgd 	case 'a':	dir = 6;	break;
    673   1.1      cgd 	case 'q':	dir = 7;	break;
    674   1.1      cgd 	default:
    675   1.1      cgd 		fprintf(stderr, "bad character in dir_no\n");
    676   1.1      cgd 		break;
    677   1.1      cgd 	}
    678   1.1      cgd 	return (dir);
    679   1.1      cgd }
    680