input.c revision 1.7 1 1.7 mrg /* $NetBSD: input.c,v 1.7 1998/03/29 04:45:17 mrg 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 1.7 mrg __RCSID("$NetBSD: input.c,v 1.7 1998/03/29 04:45:17 mrg Exp $");
54 1.3 cgd #endif
55 1.1 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 #ifdef SYSV
65 1.1 cgd #define CRTOKEN '\r'
66 1.1 cgd #endif
67 1.1 cgd #define REDRAWTOKEN '\014' /* CTRL(L) */
68 1.1 cgd #define SHELLTOKEN '!'
69 1.1 cgd #define HELPTOKEN '?'
70 1.1 cgd #define ALPHATOKEN 256
71 1.1 cgd #define NUMTOKEN 257
72 1.1 cgd
73 1.1 cgd typedef struct {
74 1.1 cgd int token;
75 1.1 cgd int to_state;
76 1.1 cgd char *str;
77 1.6 lukem char *(*func) __P((char));
78 1.1 cgd } RULE;
79 1.1 cgd
80 1.1 cgd typedef struct {
81 1.1 cgd int num_rules;
82 1.1 cgd RULE *rule;
83 1.1 cgd } STATE;
84 1.1 cgd
85 1.1 cgd typedef struct {
86 1.1 cgd char str[20];
87 1.1 cgd int state;
88 1.1 cgd int rule;
89 1.1 cgd int ch;
90 1.1 cgd int pos;
91 1.1 cgd } STACK;
92 1.1 cgd
93 1.1 cgd #define T_RULE stack[level].rule
94 1.1 cgd #define T_STATE stack[level].state
95 1.1 cgd #define T_STR stack[level].str
96 1.1 cgd #define T_POS stack[level].pos
97 1.1 cgd #define T_CH stack[level].ch
98 1.1 cgd
99 1.1 cgd #define NUMELS(a) (sizeof (a) / sizeof (*(a)))
100 1.1 cgd
101 1.1 cgd #define NUMSTATES NUMELS(st)
102 1.1 cgd
103 1.1 cgd
104 1.1 cgd RULE state0[] = { { ALPHATOKEN, 1, "%c:", setplane},
105 1.1 cgd { RETTOKEN, -1, "", NULL },
106 1.1 cgd #ifdef SYSV
107 1.1 cgd { CRTOKEN, -1, "", NULL },
108 1.1 cgd #endif
109 1.1 cgd { HELPTOKEN, 12, " [a-z]<ret>", NULL }},
110 1.1 cgd state1[] = { { 't', 2, " turn", turn },
111 1.1 cgd { 'a', 3, " altitude:", NULL },
112 1.1 cgd { 'c', 4, " circle", circle },
113 1.1 cgd { 'm', 7, " mark", mark },
114 1.1 cgd { 'u', 7, " unmark", unmark },
115 1.1 cgd { 'i', 7, " ignore", ignore },
116 1.1 cgd { HELPTOKEN, 12, " tacmui", NULL }},
117 1.1 cgd state2[] = { { 'l', 6, " left", left },
118 1.1 cgd { 'r', 6, " right", right },
119 1.1 cgd { 'L', 4, " left 90", Left },
120 1.1 cgd { 'R', 4, " right 90", Right },
121 1.1 cgd { 't', 11, " towards", NULL },
122 1.1 cgd { 'w', 4, " to 0", to_dir },
123 1.1 cgd { 'e', 4, " to 45", to_dir },
124 1.1 cgd { 'd', 4, " to 90", to_dir },
125 1.1 cgd { 'c', 4, " to 135", to_dir },
126 1.1 cgd { 'x', 4, " to 180", to_dir },
127 1.1 cgd { 'z', 4, " to 225", to_dir },
128 1.1 cgd { 'a', 4, " to 270", to_dir },
129 1.1 cgd { 'q', 4, " to 315", to_dir },
130 1.1 cgd { HELPTOKEN, 12, " lrLRt<dir>", NULL }},
131 1.1 cgd state3[] = { { '+', 10, " climb", climb },
132 1.1 cgd { 'c', 10, " climb", climb },
133 1.1 cgd { '-', 10, " descend", descend },
134 1.1 cgd { 'd', 10, " descend", descend },
135 1.1 cgd { NUMTOKEN, 7, " %c000 feet", setalt },
136 1.1 cgd { HELPTOKEN, 12, " +-cd[0-9]", NULL }},
137 1.1 cgd state4[] = { { '@', 9, " at", NULL },
138 1.1 cgd { 'a', 9, " at", NULL },
139 1.1 cgd { RETTOKEN, -1, "", NULL },
140 1.1 cgd #ifdef SYSV
141 1.1 cgd { CRTOKEN, -1, "", NULL },
142 1.1 cgd #endif
143 1.1 cgd { HELPTOKEN, 12, " @a<ret>", NULL }},
144 1.1 cgd state5[] = { { NUMTOKEN, 7, "%c", delayb },
145 1.1 cgd { HELPTOKEN, 12, " [0-9]", NULL }},
146 1.1 cgd state6[] = { { '@', 9, " at", NULL },
147 1.1 cgd { 'a', 9, " at", NULL },
148 1.1 cgd { 'w', 4, " 0", rel_dir },
149 1.1 cgd { 'e', 4, " 45", rel_dir },
150 1.1 cgd { 'd', 4, " 90", rel_dir },
151 1.1 cgd { 'c', 4, " 135", rel_dir },
152 1.1 cgd { 'x', 4, " 180", rel_dir },
153 1.1 cgd { 'z', 4, " 225", rel_dir },
154 1.1 cgd { 'a', 4, " 270", rel_dir },
155 1.1 cgd { 'q', 4, " 315", rel_dir },
156 1.1 cgd { RETTOKEN, -1, "", NULL },
157 1.1 cgd #ifdef SYSV
158 1.1 cgd { CRTOKEN, -1, "", NULL },
159 1.1 cgd #endif
160 1.1 cgd { HELPTOKEN, 12, " @a<dir><ret>",NULL }},
161 1.1 cgd state7[] = { { RETTOKEN, -1, "", NULL },
162 1.1 cgd #ifdef SYSV
163 1.1 cgd { CRTOKEN, -1, "", NULL },
164 1.1 cgd #endif
165 1.1 cgd { HELPTOKEN, 12, " <ret>", NULL }},
166 1.1 cgd state8[] = { { NUMTOKEN, 4, "%c", benum },
167 1.1 cgd { HELPTOKEN, 12, " [0-9]", NULL }},
168 1.1 cgd state9[] = { { 'b', 5, " beacon #", NULL },
169 1.1 cgd { '*', 5, " beacon #", NULL },
170 1.1 cgd { HELPTOKEN, 12, " b*", NULL }},
171 1.1 cgd state10[] = { { NUMTOKEN, 7, " %c000 ft", setrelalt},
172 1.1 cgd { HELPTOKEN, 12, " [0-9]", NULL }},
173 1.1 cgd state11[] = { { 'b', 8, " beacon #", beacon },
174 1.1 cgd { '*', 8, " beacon #", beacon },
175 1.1 cgd { 'e', 8, " exit #", ex_it },
176 1.1 cgd { 'a', 8, " airport #", airport },
177 1.1 cgd { HELPTOKEN, 12, " b*ea", NULL }},
178 1.1 cgd state12[] = { { -1, -1, "", NULL }};
179 1.1 cgd
180 1.1 cgd #define DEF_STATE(s) { NUMELS(s), (s) }
181 1.1 cgd
182 1.1 cgd STATE st[] = {
183 1.1 cgd DEF_STATE(state0), DEF_STATE(state1), DEF_STATE(state2),
184 1.1 cgd DEF_STATE(state3), DEF_STATE(state4), DEF_STATE(state5),
185 1.1 cgd DEF_STATE(state6), DEF_STATE(state7), DEF_STATE(state8),
186 1.1 cgd DEF_STATE(state9), DEF_STATE(state10), DEF_STATE(state11),
187 1.1 cgd DEF_STATE(state12)
188 1.1 cgd };
189 1.1 cgd
190 1.1 cgd PLANE p;
191 1.1 cgd STACK stack[MAXDEPTH];
192 1.1 cgd int level;
193 1.1 cgd int tval;
194 1.1 cgd int dest_type, dest_no, dir;
195 1.1 cgd
196 1.6 lukem int
197 1.1 cgd pop()
198 1.1 cgd {
199 1.1 cgd if (level == 0)
200 1.1 cgd return (-1);
201 1.1 cgd level--;
202 1.1 cgd
203 1.1 cgd ioclrtoeol(T_POS);
204 1.1 cgd
205 1.1 cgd strcpy(T_STR, "");
206 1.1 cgd T_RULE = -1;
207 1.1 cgd T_CH = -1;
208 1.1 cgd return (0);
209 1.1 cgd }
210 1.1 cgd
211 1.6 lukem void
212 1.1 cgd rezero()
213 1.1 cgd {
214 1.1 cgd iomove(0);
215 1.1 cgd
216 1.1 cgd level = 0;
217 1.1 cgd T_STATE = 0;
218 1.1 cgd T_RULE = -1;
219 1.1 cgd T_CH = -1;
220 1.1 cgd T_POS = 0;
221 1.1 cgd strcpy(T_STR, "");
222 1.1 cgd }
223 1.1 cgd
224 1.6 lukem void
225 1.1 cgd push(ruleno, ch)
226 1.6 lukem int ruleno, ch;
227 1.1 cgd {
228 1.1 cgd int newstate, newpos;
229 1.1 cgd
230 1.1 cgd (void)sprintf(T_STR, st[T_STATE].rule[ruleno].str, tval);
231 1.1 cgd T_RULE = ruleno;
232 1.1 cgd T_CH = ch;
233 1.1 cgd newstate = st[T_STATE].rule[ruleno].to_state;
234 1.1 cgd newpos = T_POS + strlen(T_STR);
235 1.1 cgd
236 1.1 cgd ioaddstr(T_POS, T_STR);
237 1.1 cgd
238 1.1 cgd if (level == 0)
239 1.1 cgd ioclrtobot();
240 1.1 cgd level++;
241 1.1 cgd T_STATE = newstate;
242 1.1 cgd T_POS = newpos;
243 1.1 cgd T_RULE = -1;
244 1.1 cgd strcpy(T_STR, "");
245 1.1 cgd }
246 1.1 cgd
247 1.6 lukem int
248 1.1 cgd getcommand()
249 1.1 cgd {
250 1.1 cgd int c, i, done;
251 1.6 lukem char *s, *(*func) __P((char));
252 1.1 cgd PLANE *pp;
253 1.1 cgd
254 1.1 cgd rezero();
255 1.1 cgd
256 1.1 cgd do {
257 1.1 cgd c = gettoken();
258 1.4 mycroft if (c == tty_new.c_cc[VERASE]) {
259 1.1 cgd if (pop() < 0)
260 1.1 cgd noise();
261 1.4 mycroft } else if (c == tty_new.c_cc[VKILL]) {
262 1.1 cgd while (pop() >= 0)
263 1.1 cgd ;
264 1.1 cgd } else {
265 1.1 cgd done = 0;
266 1.1 cgd for (i = 0; i < st[T_STATE].num_rules; i++) {
267 1.1 cgd if (st[T_STATE].rule[i].token == c ||
268 1.1 cgd st[T_STATE].rule[i].token == tval) {
269 1.1 cgd push(i, (c >= ALPHATOKEN) ? tval : c);
270 1.1 cgd done = 1;
271 1.1 cgd break;
272 1.1 cgd }
273 1.1 cgd }
274 1.1 cgd if (!done)
275 1.1 cgd noise();
276 1.1 cgd }
277 1.1 cgd } while (T_STATE != -1);
278 1.1 cgd
279 1.1 cgd if (level == 1)
280 1.1 cgd return (1); /* forced update */
281 1.1 cgd
282 1.1 cgd dest_type = T_NODEST;
283 1.1 cgd
284 1.1 cgd for (i = 0; i < level; i++) {
285 1.1 cgd func = st[stack[i].state].rule[stack[i].rule].func;
286 1.1 cgd if (func != NULL)
287 1.1 cgd if ((s = (*func)(stack[i].ch)) != NULL) {
288 1.1 cgd ioerror(stack[i].pos, strlen(stack[i].str), s);
289 1.1 cgd return (-1);
290 1.1 cgd }
291 1.1 cgd }
292 1.1 cgd
293 1.1 cgd pp = findplane(p.plane_no);
294 1.1 cgd if (pp->new_altitude != p.new_altitude)
295 1.1 cgd pp->new_altitude = p.new_altitude;
296 1.1 cgd else if (pp->status != p.status)
297 1.1 cgd pp->status = p.status;
298 1.1 cgd else {
299 1.1 cgd pp->new_dir = p.new_dir;
300 1.1 cgd pp->delayd = p.delayd;
301 1.1 cgd pp->delayd_no = p.delayd_no;
302 1.1 cgd }
303 1.1 cgd return (0);
304 1.1 cgd }
305 1.1 cgd
306 1.6 lukem void
307 1.1 cgd noise()
308 1.1 cgd {
309 1.1 cgd putchar('\07');
310 1.1 cgd fflush(stdout);
311 1.1 cgd }
312 1.1 cgd
313 1.6 lukem int
314 1.1 cgd gettoken()
315 1.1 cgd {
316 1.1 cgd while ((tval = getAChar()) == REDRAWTOKEN || tval == SHELLTOKEN)
317 1.1 cgd {
318 1.1 cgd if (tval == SHELLTOKEN)
319 1.1 cgd {
320 1.1 cgd #ifdef BSD
321 1.1 cgd struct itimerval itv;
322 1.1 cgd itv.it_value.tv_sec = 0;
323 1.1 cgd itv.it_value.tv_usec = 0;
324 1.1 cgd setitimer(ITIMER_REAL, &itv, NULL);
325 1.1 cgd #endif
326 1.1 cgd #ifdef SYSV
327 1.1 cgd int aval;
328 1.1 cgd aval = alarm(0);
329 1.1 cgd #endif
330 1.1 cgd if (fork() == 0) /* child */
331 1.1 cgd {
332 1.6 lukem char *shell, *base;
333 1.1 cgd
334 1.1 cgd setuid(getuid()); /* turn off setuid bit */
335 1.1 cgd done_screen();
336 1.1 cgd
337 1.1 cgd /* run user's favorite shell */
338 1.1 cgd if ((shell = getenv("SHELL")) != NULL)
339 1.1 cgd {
340 1.1 cgd base = strrchr(shell, '/');
341 1.1 cgd if (base == NULL)
342 1.1 cgd base = shell;
343 1.1 cgd else
344 1.1 cgd base++;
345 1.1 cgd execl(shell, base, 0);
346 1.1 cgd }
347 1.1 cgd else
348 1.1 cgd execl(_PATH_BSHELL, "sh", 0);
349 1.1 cgd
350 1.1 cgd exit(0); /* oops */
351 1.1 cgd }
352 1.1 cgd
353 1.1 cgd wait(0);
354 1.4 mycroft tcsetattr(fileno(stdin), TCSADRAIN, &tty_new);
355 1.1 cgd #ifdef BSD
356 1.1 cgd itv.it_value.tv_sec = 0;
357 1.1 cgd itv.it_value.tv_usec = 1;
358 1.1 cgd itv.it_interval.tv_sec = sp->update_secs;
359 1.1 cgd itv.it_interval.tv_usec = 0;
360 1.1 cgd setitimer(ITIMER_REAL, &itv, NULL);
361 1.1 cgd #endif
362 1.1 cgd #ifdef SYSV
363 1.1 cgd alarm(aval);
364 1.1 cgd #endif
365 1.1 cgd }
366 1.1 cgd redraw();
367 1.1 cgd }
368 1.1 cgd
369 1.1 cgd if (isdigit(tval))
370 1.1 cgd return (NUMTOKEN);
371 1.1 cgd else if (isalpha(tval))
372 1.1 cgd return (ALPHATOKEN);
373 1.1 cgd else
374 1.1 cgd return (tval);
375 1.1 cgd }
376 1.1 cgd
377 1.1 cgd char *
378 1.1 cgd setplane(c)
379 1.6 lukem char c;
380 1.1 cgd {
381 1.1 cgd PLANE *pp;
382 1.1 cgd
383 1.1 cgd pp = findplane(number(c));
384 1.1 cgd if (pp == NULL)
385 1.1 cgd return ("Unknown Plane");
386 1.5 tls memcpy(&p, pp, sizeof (p));
387 1.1 cgd p.delayd = 0;
388 1.1 cgd return (NULL);
389 1.1 cgd }
390 1.1 cgd
391 1.1 cgd char *
392 1.1 cgd turn(c)
393 1.6 lukem char c;
394 1.1 cgd {
395 1.1 cgd if (p.altitude == 0)
396 1.1 cgd return ("Planes at airports may not change direction");
397 1.1 cgd return (NULL);
398 1.1 cgd }
399 1.1 cgd
400 1.1 cgd char *
401 1.1 cgd circle(c)
402 1.6 lukem char c;
403 1.1 cgd {
404 1.1 cgd if (p.altitude == 0)
405 1.1 cgd return ("Planes cannot circle on the ground");
406 1.1 cgd p.new_dir = MAXDIR;
407 1.1 cgd return (NULL);
408 1.1 cgd }
409 1.1 cgd
410 1.1 cgd char *
411 1.1 cgd left(c)
412 1.6 lukem char c;
413 1.1 cgd {
414 1.1 cgd dir = D_LEFT;
415 1.1 cgd p.new_dir = p.dir - 1;
416 1.1 cgd if (p.new_dir < 0)
417 1.1 cgd p.new_dir += MAXDIR;
418 1.1 cgd return (NULL);
419 1.1 cgd }
420 1.1 cgd
421 1.1 cgd char *
422 1.1 cgd right(c)
423 1.6 lukem char c;
424 1.1 cgd {
425 1.1 cgd dir = D_RIGHT;
426 1.1 cgd p.new_dir = p.dir + 1;
427 1.1 cgd if (p.new_dir > MAXDIR)
428 1.1 cgd p.new_dir -= MAXDIR;
429 1.1 cgd return (NULL);
430 1.1 cgd }
431 1.1 cgd
432 1.1 cgd char *
433 1.1 cgd Left(c)
434 1.6 lukem char c;
435 1.1 cgd {
436 1.1 cgd p.new_dir = p.dir - 2;
437 1.1 cgd if (p.new_dir < 0)
438 1.1 cgd p.new_dir += MAXDIR;
439 1.1 cgd return (NULL);
440 1.1 cgd }
441 1.1 cgd
442 1.1 cgd char *
443 1.1 cgd Right(c)
444 1.6 lukem char c;
445 1.1 cgd {
446 1.1 cgd p.new_dir = p.dir + 2;
447 1.1 cgd if (p.new_dir > MAXDIR)
448 1.1 cgd p.new_dir -= MAXDIR;
449 1.1 cgd return (NULL);
450 1.1 cgd }
451 1.1 cgd
452 1.1 cgd char *
453 1.1 cgd delayb(c)
454 1.6 lukem char c;
455 1.1 cgd {
456 1.1 cgd int xdiff, ydiff;
457 1.1 cgd
458 1.1 cgd c -= '0';
459 1.1 cgd
460 1.1 cgd if (c >= sp->num_beacons)
461 1.1 cgd return ("Unknown beacon");
462 1.7 mrg xdiff = sp->beacon[(int)c].x - p.xpos;
463 1.1 cgd xdiff = SGN(xdiff);
464 1.7 mrg ydiff = sp->beacon[(int)c].y - p.ypos;
465 1.1 cgd ydiff = SGN(ydiff);
466 1.1 cgd if (xdiff != displacement[p.dir].dx || ydiff != displacement[p.dir].dy)
467 1.1 cgd return ("Beacon is not in flight path");
468 1.1 cgd p.delayd = 1;
469 1.1 cgd p.delayd_no = c;
470 1.1 cgd
471 1.1 cgd if (dest_type != T_NODEST) {
472 1.1 cgd switch (dest_type) {
473 1.1 cgd case T_BEACON:
474 1.7 mrg xdiff = sp->beacon[dest_no].x - sp->beacon[(int)c].x;
475 1.7 mrg ydiff = sp->beacon[dest_no].y - sp->beacon[(int)c].y;
476 1.1 cgd break;
477 1.1 cgd case T_EXIT:
478 1.7 mrg xdiff = sp->exit[dest_no].x - sp->beacon[(int)c].x;
479 1.7 mrg ydiff = sp->exit[dest_no].y - sp->beacon[(int)c].y;
480 1.1 cgd break;
481 1.1 cgd case T_AIRPORT:
482 1.7 mrg xdiff = sp->airport[dest_no].x - sp->beacon[(int)c].x;
483 1.7 mrg ydiff = sp->airport[dest_no].y - sp->beacon[(int)c].y;
484 1.1 cgd break;
485 1.1 cgd default:
486 1.1 cgd return ("Bad case in delayb! Get help!");
487 1.1 cgd break;
488 1.1 cgd }
489 1.1 cgd if (xdiff == 0 && ydiff == 0)
490 1.1 cgd return ("Would already be there");
491 1.1 cgd p.new_dir = DIR_FROM_DXDY(xdiff, ydiff);
492 1.1 cgd if (p.new_dir == p.dir)
493 1.1 cgd return ("Already going in that direction");
494 1.1 cgd }
495 1.1 cgd return (NULL);
496 1.1 cgd }
497 1.1 cgd
498 1.1 cgd char *
499 1.1 cgd beacon(c)
500 1.6 lukem char c;
501 1.1 cgd {
502 1.1 cgd dest_type = T_BEACON;
503 1.1 cgd return (NULL);
504 1.1 cgd }
505 1.1 cgd
506 1.1 cgd char *
507 1.1 cgd ex_it(c)
508 1.6 lukem char c;
509 1.1 cgd {
510 1.1 cgd dest_type = T_EXIT;
511 1.1 cgd return (NULL);
512 1.1 cgd }
513 1.1 cgd
514 1.1 cgd char *
515 1.1 cgd airport(c)
516 1.6 lukem char c;
517 1.1 cgd {
518 1.1 cgd dest_type = T_AIRPORT;
519 1.1 cgd return (NULL);
520 1.1 cgd }
521 1.1 cgd
522 1.1 cgd char *
523 1.1 cgd climb(c)
524 1.6 lukem char c;
525 1.1 cgd {
526 1.1 cgd dir = D_UP;
527 1.1 cgd return (NULL);
528 1.1 cgd }
529 1.1 cgd
530 1.1 cgd char *
531 1.1 cgd descend(c)
532 1.6 lukem char c;
533 1.1 cgd {
534 1.1 cgd dir = D_DOWN;
535 1.1 cgd return (NULL);
536 1.1 cgd }
537 1.1 cgd
538 1.1 cgd char *
539 1.1 cgd setalt(c)
540 1.6 lukem char c;
541 1.1 cgd {
542 1.1 cgd if ((p.altitude == c - '0') && (p.new_altitude == p.altitude))
543 1.1 cgd return ("Already at that altitude");
544 1.1 cgd p.new_altitude = c - '0';
545 1.1 cgd return (NULL);
546 1.1 cgd }
547 1.1 cgd
548 1.1 cgd char *
549 1.1 cgd setrelalt(c)
550 1.6 lukem char c;
551 1.1 cgd {
552 1.1 cgd if (c == 0)
553 1.1 cgd return ("altitude not changed");
554 1.1 cgd
555 1.1 cgd switch (dir) {
556 1.1 cgd case D_UP:
557 1.1 cgd p.new_altitude = p.altitude + c - '0';
558 1.1 cgd break;
559 1.1 cgd case D_DOWN:
560 1.1 cgd p.new_altitude = p.altitude - (c - '0');
561 1.1 cgd break;
562 1.1 cgd default:
563 1.1 cgd return ("Unknown case in setrelalt! Get help!");
564 1.1 cgd break;
565 1.1 cgd }
566 1.1 cgd if (p.new_altitude < 0)
567 1.1 cgd return ("Altitude would be too low");
568 1.1 cgd else if (p.new_altitude > 9)
569 1.1 cgd return ("Altitude would be too high");
570 1.1 cgd return (NULL);
571 1.1 cgd }
572 1.1 cgd
573 1.1 cgd char *
574 1.1 cgd benum(c)
575 1.6 lukem char c;
576 1.1 cgd {
577 1.1 cgd dest_no = c -= '0';
578 1.1 cgd
579 1.1 cgd switch (dest_type) {
580 1.1 cgd case T_BEACON:
581 1.1 cgd if (c >= sp->num_beacons)
582 1.1 cgd return ("Unknown beacon");
583 1.7 mrg p.new_dir = DIR_FROM_DXDY(sp->beacon[(int)c].x - p.xpos,
584 1.7 mrg sp->beacon[(int)c].y - p.ypos);
585 1.1 cgd break;
586 1.1 cgd case T_EXIT:
587 1.1 cgd if (c >= sp->num_exits)
588 1.1 cgd return ("Unknown exit");
589 1.7 mrg p.new_dir = DIR_FROM_DXDY(sp->exit[(int)c].x - p.xpos,
590 1.7 mrg sp->exit[(int)c].y - p.ypos);
591 1.1 cgd break;
592 1.1 cgd case T_AIRPORT:
593 1.1 cgd if (c >= sp->num_airports)
594 1.1 cgd return ("Unknown airport");
595 1.7 mrg p.new_dir = DIR_FROM_DXDY(sp->airport[(int)c].x - p.xpos,
596 1.7 mrg sp->airport[(int)c].y - p.ypos);
597 1.1 cgd break;
598 1.1 cgd default:
599 1.1 cgd return ("Unknown case in benum! Get help!");
600 1.1 cgd break;
601 1.1 cgd }
602 1.1 cgd return (NULL);
603 1.1 cgd }
604 1.1 cgd
605 1.1 cgd char *
606 1.1 cgd to_dir(c)
607 1.6 lukem char c;
608 1.1 cgd {
609 1.1 cgd p.new_dir = dir_no(c);
610 1.1 cgd return (NULL);
611 1.1 cgd }
612 1.1 cgd
613 1.1 cgd char *
614 1.1 cgd rel_dir(c)
615 1.6 lukem char c;
616 1.1 cgd {
617 1.1 cgd int angle;
618 1.1 cgd
619 1.1 cgd angle = dir_no(c);
620 1.1 cgd switch (dir) {
621 1.1 cgd case D_LEFT:
622 1.1 cgd p.new_dir = p.dir - angle;
623 1.1 cgd if (p.new_dir < 0)
624 1.1 cgd p.new_dir += MAXDIR;
625 1.1 cgd break;
626 1.1 cgd case D_RIGHT:
627 1.1 cgd p.new_dir = p.dir + angle;
628 1.1 cgd if (p.new_dir >= MAXDIR)
629 1.1 cgd p.new_dir -= MAXDIR;
630 1.1 cgd break;
631 1.1 cgd default:
632 1.1 cgd return ("Bizarre direction in rel_dir! Get help!");
633 1.1 cgd break;
634 1.1 cgd }
635 1.1 cgd return (NULL);
636 1.1 cgd }
637 1.1 cgd
638 1.1 cgd char *
639 1.1 cgd mark(c)
640 1.6 lukem char c;
641 1.1 cgd {
642 1.1 cgd if (p.altitude == 0)
643 1.1 cgd return ("Cannot mark planes on the ground");
644 1.1 cgd if (p.status == S_MARKED)
645 1.1 cgd return ("Already marked");
646 1.1 cgd p.status = S_MARKED;
647 1.1 cgd return (NULL);
648 1.1 cgd }
649 1.1 cgd
650 1.1 cgd char *
651 1.1 cgd unmark(c)
652 1.6 lukem char c;
653 1.1 cgd {
654 1.1 cgd if (p.altitude == 0)
655 1.1 cgd return ("Cannot unmark planes on the ground");
656 1.1 cgd if (p.status == S_UNMARKED)
657 1.1 cgd return ("Already unmarked");
658 1.1 cgd p.status = S_UNMARKED;
659 1.1 cgd return (NULL);
660 1.1 cgd }
661 1.1 cgd
662 1.1 cgd char *
663 1.1 cgd ignore(c)
664 1.6 lukem char c;
665 1.1 cgd {
666 1.1 cgd if (p.altitude == 0)
667 1.1 cgd return ("Cannot ignore planes on the ground");
668 1.1 cgd if (p.status == S_IGNORED)
669 1.1 cgd return ("Already ignored");
670 1.1 cgd p.status = S_IGNORED;
671 1.1 cgd return (NULL);
672 1.1 cgd }
673 1.1 cgd
674 1.6 lukem int
675 1.1 cgd dir_no(ch)
676 1.1 cgd char ch;
677 1.1 cgd {
678 1.1 cgd int dir;
679 1.1 cgd
680 1.6 lukem dir = -1;
681 1.1 cgd switch (ch) {
682 1.1 cgd case 'w': dir = 0; break;
683 1.1 cgd case 'e': dir = 1; break;
684 1.1 cgd case 'd': dir = 2; break;
685 1.1 cgd case 'c': dir = 3; break;
686 1.1 cgd case 'x': dir = 4; break;
687 1.1 cgd case 'z': dir = 5; break;
688 1.1 cgd case 'a': dir = 6; break;
689 1.1 cgd case 'q': dir = 7; break;
690 1.1 cgd default:
691 1.1 cgd fprintf(stderr, "bad character in dir_no\n");
692 1.1 cgd break;
693 1.1 cgd }
694 1.1 cgd return (dir);
695 1.1 cgd }
696