input.c revision 1.5 1 1.5 tls /* $NetBSD: input.c,v 1.5 1997/01/13 06:50:25 tls 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 1.1 cgd #ifndef lint
49 1.3 cgd #if 0
50 1.3 cgd static char sccsid[] = "@(#)input.c 8.1 (Berkeley) 5/31/93";
51 1.3 cgd #else
52 1.5 tls static char rcsid[] = "$NetBSD: input.c,v 1.5 1997/01/13 06:50:25 tls Exp $";
53 1.3 cgd #endif
54 1.1 cgd #endif not lint
55 1.1 cgd
56 1.1 cgd #include "include.h"
57 1.1 cgd #include "pathnames.h"
58 1.1 cgd
59 1.1 cgd #define MAXRULES 6
60 1.1 cgd #define MAXDEPTH 15
61 1.1 cgd
62 1.1 cgd #define RETTOKEN '\n'
63 1.1 cgd #ifdef SYSV
64 1.1 cgd #define CRTOKEN '\r'
65 1.1 cgd #endif
66 1.1 cgd #define REDRAWTOKEN '\014' /* CTRL(L) */
67 1.1 cgd #define SHELLTOKEN '!'
68 1.1 cgd #define HELPTOKEN '?'
69 1.1 cgd #define ALPHATOKEN 256
70 1.1 cgd #define NUMTOKEN 257
71 1.1 cgd
72 1.1 cgd typedef struct {
73 1.1 cgd int token;
74 1.1 cgd int to_state;
75 1.1 cgd char *str;
76 1.1 cgd char *(*func)();
77 1.1 cgd } RULE;
78 1.1 cgd
79 1.1 cgd typedef struct {
80 1.1 cgd int num_rules;
81 1.1 cgd RULE *rule;
82 1.1 cgd } STATE;
83 1.1 cgd
84 1.1 cgd typedef struct {
85 1.1 cgd char str[20];
86 1.1 cgd int state;
87 1.1 cgd int rule;
88 1.1 cgd int ch;
89 1.1 cgd int pos;
90 1.1 cgd } STACK;
91 1.1 cgd
92 1.1 cgd #define T_RULE stack[level].rule
93 1.1 cgd #define T_STATE stack[level].state
94 1.1 cgd #define T_STR stack[level].str
95 1.1 cgd #define T_POS stack[level].pos
96 1.1 cgd #define T_CH stack[level].ch
97 1.1 cgd
98 1.1 cgd #define NUMELS(a) (sizeof (a) / sizeof (*(a)))
99 1.1 cgd
100 1.1 cgd #define NUMSTATES NUMELS(st)
101 1.1 cgd
102 1.1 cgd char *setplane(), *circle(), *left(), *right(), *Left(), *Right(),
103 1.1 cgd *beacon(), *ex_it(), *climb(), *descend(), *setalt(), *setrelalt(),
104 1.1 cgd *benum(), *to_dir(), *rel_dir(), *delayb(), *mark(), *unmark(),
105 1.1 cgd *airport(), *turn(), *ignore();
106 1.1 cgd
107 1.1 cgd RULE state0[] = { { ALPHATOKEN, 1, "%c:", setplane},
108 1.1 cgd { RETTOKEN, -1, "", NULL },
109 1.1 cgd #ifdef SYSV
110 1.1 cgd { CRTOKEN, -1, "", NULL },
111 1.1 cgd #endif
112 1.1 cgd { HELPTOKEN, 12, " [a-z]<ret>", NULL }},
113 1.1 cgd state1[] = { { 't', 2, " turn", turn },
114 1.1 cgd { 'a', 3, " altitude:", NULL },
115 1.1 cgd { 'c', 4, " circle", circle },
116 1.1 cgd { 'm', 7, " mark", mark },
117 1.1 cgd { 'u', 7, " unmark", unmark },
118 1.1 cgd { 'i', 7, " ignore", ignore },
119 1.1 cgd { HELPTOKEN, 12, " tacmui", NULL }},
120 1.1 cgd state2[] = { { 'l', 6, " left", left },
121 1.1 cgd { 'r', 6, " right", right },
122 1.1 cgd { 'L', 4, " left 90", Left },
123 1.1 cgd { 'R', 4, " right 90", Right },
124 1.1 cgd { 't', 11, " towards", NULL },
125 1.1 cgd { 'w', 4, " to 0", to_dir },
126 1.1 cgd { 'e', 4, " to 45", to_dir },
127 1.1 cgd { 'd', 4, " to 90", to_dir },
128 1.1 cgd { 'c', 4, " to 135", to_dir },
129 1.1 cgd { 'x', 4, " to 180", to_dir },
130 1.1 cgd { 'z', 4, " to 225", to_dir },
131 1.1 cgd { 'a', 4, " to 270", to_dir },
132 1.1 cgd { 'q', 4, " to 315", to_dir },
133 1.1 cgd { HELPTOKEN, 12, " lrLRt<dir>", NULL }},
134 1.1 cgd state3[] = { { '+', 10, " climb", climb },
135 1.1 cgd { 'c', 10, " climb", climb },
136 1.1 cgd { '-', 10, " descend", descend },
137 1.1 cgd { 'd', 10, " descend", descend },
138 1.1 cgd { NUMTOKEN, 7, " %c000 feet", setalt },
139 1.1 cgd { HELPTOKEN, 12, " +-cd[0-9]", NULL }},
140 1.1 cgd state4[] = { { '@', 9, " at", NULL },
141 1.1 cgd { 'a', 9, " at", NULL },
142 1.1 cgd { RETTOKEN, -1, "", NULL },
143 1.1 cgd #ifdef SYSV
144 1.1 cgd { CRTOKEN, -1, "", NULL },
145 1.1 cgd #endif
146 1.1 cgd { HELPTOKEN, 12, " @a<ret>", NULL }},
147 1.1 cgd state5[] = { { NUMTOKEN, 7, "%c", delayb },
148 1.1 cgd { HELPTOKEN, 12, " [0-9]", NULL }},
149 1.1 cgd state6[] = { { '@', 9, " at", NULL },
150 1.1 cgd { 'a', 9, " at", NULL },
151 1.1 cgd { 'w', 4, " 0", rel_dir },
152 1.1 cgd { 'e', 4, " 45", rel_dir },
153 1.1 cgd { 'd', 4, " 90", rel_dir },
154 1.1 cgd { 'c', 4, " 135", rel_dir },
155 1.1 cgd { 'x', 4, " 180", rel_dir },
156 1.1 cgd { 'z', 4, " 225", rel_dir },
157 1.1 cgd { 'a', 4, " 270", rel_dir },
158 1.1 cgd { 'q', 4, " 315", rel_dir },
159 1.1 cgd { RETTOKEN, -1, "", NULL },
160 1.1 cgd #ifdef SYSV
161 1.1 cgd { CRTOKEN, -1, "", NULL },
162 1.1 cgd #endif
163 1.1 cgd { HELPTOKEN, 12, " @a<dir><ret>",NULL }},
164 1.1 cgd state7[] = { { RETTOKEN, -1, "", NULL },
165 1.1 cgd #ifdef SYSV
166 1.1 cgd { CRTOKEN, -1, "", NULL },
167 1.1 cgd #endif
168 1.1 cgd { HELPTOKEN, 12, " <ret>", NULL }},
169 1.1 cgd state8[] = { { NUMTOKEN, 4, "%c", benum },
170 1.1 cgd { HELPTOKEN, 12, " [0-9]", NULL }},
171 1.1 cgd state9[] = { { 'b', 5, " beacon #", NULL },
172 1.1 cgd { '*', 5, " beacon #", NULL },
173 1.1 cgd { HELPTOKEN, 12, " b*", NULL }},
174 1.1 cgd state10[] = { { NUMTOKEN, 7, " %c000 ft", setrelalt},
175 1.1 cgd { HELPTOKEN, 12, " [0-9]", NULL }},
176 1.1 cgd state11[] = { { 'b', 8, " beacon #", beacon },
177 1.1 cgd { '*', 8, " beacon #", beacon },
178 1.1 cgd { 'e', 8, " exit #", ex_it },
179 1.1 cgd { 'a', 8, " airport #", airport },
180 1.1 cgd { HELPTOKEN, 12, " b*ea", NULL }},
181 1.1 cgd state12[] = { { -1, -1, "", NULL }};
182 1.1 cgd
183 1.1 cgd #define DEF_STATE(s) { NUMELS(s), (s) }
184 1.1 cgd
185 1.1 cgd STATE st[] = {
186 1.1 cgd DEF_STATE(state0), DEF_STATE(state1), DEF_STATE(state2),
187 1.1 cgd DEF_STATE(state3), DEF_STATE(state4), DEF_STATE(state5),
188 1.1 cgd DEF_STATE(state6), DEF_STATE(state7), DEF_STATE(state8),
189 1.1 cgd DEF_STATE(state9), DEF_STATE(state10), DEF_STATE(state11),
190 1.1 cgd DEF_STATE(state12)
191 1.1 cgd };
192 1.1 cgd
193 1.1 cgd PLANE p;
194 1.1 cgd STACK stack[MAXDEPTH];
195 1.1 cgd int level;
196 1.1 cgd int tval;
197 1.1 cgd int dest_type, dest_no, dir;
198 1.1 cgd
199 1.1 cgd pop()
200 1.1 cgd {
201 1.1 cgd if (level == 0)
202 1.1 cgd return (-1);
203 1.1 cgd level--;
204 1.1 cgd
205 1.1 cgd ioclrtoeol(T_POS);
206 1.1 cgd
207 1.1 cgd strcpy(T_STR, "");
208 1.1 cgd T_RULE = -1;
209 1.1 cgd T_CH = -1;
210 1.1 cgd return (0);
211 1.1 cgd }
212 1.1 cgd
213 1.1 cgd rezero()
214 1.1 cgd {
215 1.1 cgd iomove(0);
216 1.1 cgd
217 1.1 cgd level = 0;
218 1.1 cgd T_STATE = 0;
219 1.1 cgd T_RULE = -1;
220 1.1 cgd T_CH = -1;
221 1.1 cgd T_POS = 0;
222 1.1 cgd strcpy(T_STR, "");
223 1.1 cgd }
224 1.1 cgd
225 1.1 cgd push(ruleno, ch)
226 1.1 cgd {
227 1.1 cgd int newstate, newpos;
228 1.1 cgd
229 1.1 cgd (void)sprintf(T_STR, st[T_STATE].rule[ruleno].str, tval);
230 1.1 cgd T_RULE = ruleno;
231 1.1 cgd T_CH = ch;
232 1.1 cgd newstate = st[T_STATE].rule[ruleno].to_state;
233 1.1 cgd newpos = T_POS + strlen(T_STR);
234 1.1 cgd
235 1.1 cgd ioaddstr(T_POS, T_STR);
236 1.1 cgd
237 1.1 cgd if (level == 0)
238 1.1 cgd ioclrtobot();
239 1.1 cgd level++;
240 1.1 cgd T_STATE = newstate;
241 1.1 cgd T_POS = newpos;
242 1.1 cgd T_RULE = -1;
243 1.1 cgd strcpy(T_STR, "");
244 1.1 cgd }
245 1.1 cgd
246 1.1 cgd getcommand()
247 1.1 cgd {
248 1.1 cgd int c, i, done;
249 1.1 cgd char *s, *(*func)();
250 1.1 cgd PLANE *pp;
251 1.1 cgd
252 1.1 cgd rezero();
253 1.1 cgd
254 1.1 cgd do {
255 1.1 cgd c = gettoken();
256 1.4 mycroft if (c == tty_new.c_cc[VERASE]) {
257 1.1 cgd if (pop() < 0)
258 1.1 cgd noise();
259 1.4 mycroft } else if (c == tty_new.c_cc[VKILL]) {
260 1.1 cgd while (pop() >= 0)
261 1.1 cgd ;
262 1.1 cgd } else {
263 1.1 cgd done = 0;
264 1.1 cgd for (i = 0; i < st[T_STATE].num_rules; i++) {
265 1.1 cgd if (st[T_STATE].rule[i].token == c ||
266 1.1 cgd st[T_STATE].rule[i].token == tval) {
267 1.1 cgd push(i, (c >= ALPHATOKEN) ? tval : c);
268 1.1 cgd done = 1;
269 1.1 cgd break;
270 1.1 cgd }
271 1.1 cgd }
272 1.1 cgd if (!done)
273 1.1 cgd noise();
274 1.1 cgd }
275 1.1 cgd } while (T_STATE != -1);
276 1.1 cgd
277 1.1 cgd if (level == 1)
278 1.1 cgd return (1); /* forced update */
279 1.1 cgd
280 1.1 cgd dest_type = T_NODEST;
281 1.1 cgd
282 1.1 cgd for (i = 0; i < level; i++) {
283 1.1 cgd func = st[stack[i].state].rule[stack[i].rule].func;
284 1.1 cgd if (func != NULL)
285 1.1 cgd if ((s = (*func)(stack[i].ch)) != NULL) {
286 1.1 cgd ioerror(stack[i].pos, strlen(stack[i].str), s);
287 1.1 cgd return (-1);
288 1.1 cgd }
289 1.1 cgd }
290 1.1 cgd
291 1.1 cgd pp = findplane(p.plane_no);
292 1.1 cgd if (pp->new_altitude != p.new_altitude)
293 1.1 cgd pp->new_altitude = p.new_altitude;
294 1.1 cgd else if (pp->status != p.status)
295 1.1 cgd pp->status = p.status;
296 1.1 cgd else {
297 1.1 cgd pp->new_dir = p.new_dir;
298 1.1 cgd pp->delayd = p.delayd;
299 1.1 cgd pp->delayd_no = p.delayd_no;
300 1.1 cgd }
301 1.1 cgd return (0);
302 1.1 cgd }
303 1.1 cgd
304 1.1 cgd noise()
305 1.1 cgd {
306 1.1 cgd putchar('\07');
307 1.1 cgd fflush(stdout);
308 1.1 cgd }
309 1.1 cgd
310 1.1 cgd gettoken()
311 1.1 cgd {
312 1.1 cgd while ((tval = getAChar()) == REDRAWTOKEN || tval == SHELLTOKEN)
313 1.1 cgd {
314 1.1 cgd if (tval == SHELLTOKEN)
315 1.1 cgd {
316 1.1 cgd #ifdef BSD
317 1.1 cgd struct itimerval itv;
318 1.1 cgd itv.it_value.tv_sec = 0;
319 1.1 cgd itv.it_value.tv_usec = 0;
320 1.1 cgd setitimer(ITIMER_REAL, &itv, NULL);
321 1.1 cgd #endif
322 1.1 cgd #ifdef SYSV
323 1.1 cgd int aval;
324 1.1 cgd aval = alarm(0);
325 1.1 cgd #endif
326 1.1 cgd if (fork() == 0) /* child */
327 1.1 cgd {
328 1.1 cgd char *shell, *base, *getenv(), *strrchr();
329 1.1 cgd
330 1.1 cgd setuid(getuid()); /* turn off setuid bit */
331 1.1 cgd done_screen();
332 1.1 cgd
333 1.1 cgd /* run user's favorite shell */
334 1.1 cgd if ((shell = getenv("SHELL")) != NULL)
335 1.1 cgd {
336 1.1 cgd base = strrchr(shell, '/');
337 1.1 cgd if (base == NULL)
338 1.1 cgd base = shell;
339 1.1 cgd else
340 1.1 cgd base++;
341 1.1 cgd execl(shell, base, 0);
342 1.1 cgd }
343 1.1 cgd else
344 1.1 cgd execl(_PATH_BSHELL, "sh", 0);
345 1.1 cgd
346 1.1 cgd exit(0); /* oops */
347 1.1 cgd }
348 1.1 cgd
349 1.1 cgd wait(0);
350 1.4 mycroft tcsetattr(fileno(stdin), TCSADRAIN, &tty_new);
351 1.1 cgd #ifdef BSD
352 1.1 cgd itv.it_value.tv_sec = 0;
353 1.1 cgd itv.it_value.tv_usec = 1;
354 1.1 cgd itv.it_interval.tv_sec = sp->update_secs;
355 1.1 cgd itv.it_interval.tv_usec = 0;
356 1.1 cgd setitimer(ITIMER_REAL, &itv, NULL);
357 1.1 cgd #endif
358 1.1 cgd #ifdef SYSV
359 1.1 cgd alarm(aval);
360 1.1 cgd #endif
361 1.1 cgd }
362 1.1 cgd redraw();
363 1.1 cgd }
364 1.1 cgd
365 1.1 cgd if (isdigit(tval))
366 1.1 cgd return (NUMTOKEN);
367 1.1 cgd else if (isalpha(tval))
368 1.1 cgd return (ALPHATOKEN);
369 1.1 cgd else
370 1.1 cgd return (tval);
371 1.1 cgd }
372 1.1 cgd
373 1.1 cgd char *
374 1.1 cgd setplane(c)
375 1.1 cgd {
376 1.1 cgd PLANE *pp;
377 1.1 cgd
378 1.1 cgd pp = findplane(number(c));
379 1.1 cgd if (pp == NULL)
380 1.1 cgd return ("Unknown Plane");
381 1.5 tls memcpy(&p, pp, sizeof (p));
382 1.1 cgd p.delayd = 0;
383 1.1 cgd return (NULL);
384 1.1 cgd }
385 1.1 cgd
386 1.1 cgd char *
387 1.1 cgd turn(c)
388 1.1 cgd {
389 1.1 cgd if (p.altitude == 0)
390 1.1 cgd return ("Planes at airports may not change direction");
391 1.1 cgd return (NULL);
392 1.1 cgd }
393 1.1 cgd
394 1.1 cgd char *
395 1.1 cgd circle(c)
396 1.1 cgd {
397 1.1 cgd if (p.altitude == 0)
398 1.1 cgd return ("Planes cannot circle on the ground");
399 1.1 cgd p.new_dir = MAXDIR;
400 1.1 cgd return (NULL);
401 1.1 cgd }
402 1.1 cgd
403 1.1 cgd char *
404 1.1 cgd left(c)
405 1.1 cgd {
406 1.1 cgd dir = D_LEFT;
407 1.1 cgd p.new_dir = p.dir - 1;
408 1.1 cgd if (p.new_dir < 0)
409 1.1 cgd p.new_dir += MAXDIR;
410 1.1 cgd return (NULL);
411 1.1 cgd }
412 1.1 cgd
413 1.1 cgd char *
414 1.1 cgd right(c)
415 1.1 cgd {
416 1.1 cgd dir = D_RIGHT;
417 1.1 cgd p.new_dir = p.dir + 1;
418 1.1 cgd if (p.new_dir > MAXDIR)
419 1.1 cgd p.new_dir -= MAXDIR;
420 1.1 cgd return (NULL);
421 1.1 cgd }
422 1.1 cgd
423 1.1 cgd char *
424 1.1 cgd Left(c)
425 1.1 cgd {
426 1.1 cgd p.new_dir = p.dir - 2;
427 1.1 cgd if (p.new_dir < 0)
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 Right(c)
434 1.1 cgd {
435 1.1 cgd p.new_dir = p.dir + 2;
436 1.1 cgd if (p.new_dir > MAXDIR)
437 1.1 cgd p.new_dir -= MAXDIR;
438 1.1 cgd return (NULL);
439 1.1 cgd }
440 1.1 cgd
441 1.1 cgd char *
442 1.1 cgd delayb(c)
443 1.1 cgd {
444 1.1 cgd int xdiff, ydiff;
445 1.1 cgd
446 1.1 cgd c -= '0';
447 1.1 cgd
448 1.1 cgd if (c >= sp->num_beacons)
449 1.1 cgd return ("Unknown beacon");
450 1.1 cgd xdiff = sp->beacon[c].x - p.xpos;
451 1.1 cgd xdiff = SGN(xdiff);
452 1.1 cgd ydiff = sp->beacon[c].y - p.ypos;
453 1.1 cgd ydiff = SGN(ydiff);
454 1.1 cgd if (xdiff != displacement[p.dir].dx || ydiff != displacement[p.dir].dy)
455 1.1 cgd return ("Beacon is not in flight path");
456 1.1 cgd p.delayd = 1;
457 1.1 cgd p.delayd_no = c;
458 1.1 cgd
459 1.1 cgd if (dest_type != T_NODEST) {
460 1.1 cgd switch (dest_type) {
461 1.1 cgd case T_BEACON:
462 1.1 cgd xdiff = sp->beacon[dest_no].x - sp->beacon[c].x;
463 1.1 cgd ydiff = sp->beacon[dest_no].y - sp->beacon[c].y;
464 1.1 cgd break;
465 1.1 cgd case T_EXIT:
466 1.1 cgd xdiff = sp->exit[dest_no].x - sp->beacon[c].x;
467 1.1 cgd ydiff = sp->exit[dest_no].y - sp->beacon[c].y;
468 1.1 cgd break;
469 1.1 cgd case T_AIRPORT:
470 1.1 cgd xdiff = sp->airport[dest_no].x - sp->beacon[c].x;
471 1.1 cgd ydiff = sp->airport[dest_no].y - sp->beacon[c].y;
472 1.1 cgd break;
473 1.1 cgd default:
474 1.1 cgd return ("Bad case in delayb! Get help!");
475 1.1 cgd break;
476 1.1 cgd }
477 1.1 cgd if (xdiff == 0 && ydiff == 0)
478 1.1 cgd return ("Would already be there");
479 1.1 cgd p.new_dir = DIR_FROM_DXDY(xdiff, ydiff);
480 1.1 cgd if (p.new_dir == p.dir)
481 1.1 cgd return ("Already going in that direction");
482 1.1 cgd }
483 1.1 cgd return (NULL);
484 1.1 cgd }
485 1.1 cgd
486 1.1 cgd char *
487 1.1 cgd beacon(c)
488 1.1 cgd {
489 1.1 cgd dest_type = T_BEACON;
490 1.1 cgd return (NULL);
491 1.1 cgd }
492 1.1 cgd
493 1.1 cgd char *
494 1.1 cgd ex_it(c)
495 1.1 cgd {
496 1.1 cgd dest_type = T_EXIT;
497 1.1 cgd return (NULL);
498 1.1 cgd }
499 1.1 cgd
500 1.1 cgd char *
501 1.1 cgd airport(c)
502 1.1 cgd {
503 1.1 cgd dest_type = T_AIRPORT;
504 1.1 cgd return (NULL);
505 1.1 cgd }
506 1.1 cgd
507 1.1 cgd char *
508 1.1 cgd climb(c)
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 1.1 cgd char *
515 1.1 cgd descend(c)
516 1.1 cgd {
517 1.1 cgd dir = D_DOWN;
518 1.1 cgd return (NULL);
519 1.1 cgd }
520 1.1 cgd
521 1.1 cgd char *
522 1.1 cgd setalt(c)
523 1.1 cgd {
524 1.1 cgd if ((p.altitude == c - '0') && (p.new_altitude == p.altitude))
525 1.1 cgd return ("Already at that altitude");
526 1.1 cgd p.new_altitude = c - '0';
527 1.1 cgd return (NULL);
528 1.1 cgd }
529 1.1 cgd
530 1.1 cgd char *
531 1.1 cgd setrelalt(c)
532 1.1 cgd {
533 1.1 cgd if (c == 0)
534 1.1 cgd return ("altitude not changed");
535 1.1 cgd
536 1.1 cgd switch (dir) {
537 1.1 cgd case D_UP:
538 1.1 cgd p.new_altitude = p.altitude + c - '0';
539 1.1 cgd break;
540 1.1 cgd case D_DOWN:
541 1.1 cgd p.new_altitude = p.altitude - (c - '0');
542 1.1 cgd break;
543 1.1 cgd default:
544 1.1 cgd return ("Unknown case in setrelalt! Get help!");
545 1.1 cgd break;
546 1.1 cgd }
547 1.1 cgd if (p.new_altitude < 0)
548 1.1 cgd return ("Altitude would be too low");
549 1.1 cgd else if (p.new_altitude > 9)
550 1.1 cgd return ("Altitude would be too high");
551 1.1 cgd return (NULL);
552 1.1 cgd }
553 1.1 cgd
554 1.1 cgd char *
555 1.1 cgd benum(c)
556 1.1 cgd {
557 1.1 cgd dest_no = c -= '0';
558 1.1 cgd
559 1.1 cgd switch (dest_type) {
560 1.1 cgd case T_BEACON:
561 1.1 cgd if (c >= sp->num_beacons)
562 1.1 cgd return ("Unknown beacon");
563 1.1 cgd p.new_dir = DIR_FROM_DXDY(sp->beacon[c].x - p.xpos,
564 1.1 cgd sp->beacon[c].y - p.ypos);
565 1.1 cgd break;
566 1.1 cgd case T_EXIT:
567 1.1 cgd if (c >= sp->num_exits)
568 1.1 cgd return ("Unknown exit");
569 1.1 cgd p.new_dir = DIR_FROM_DXDY(sp->exit[c].x - p.xpos,
570 1.1 cgd sp->exit[c].y - p.ypos);
571 1.1 cgd break;
572 1.1 cgd case T_AIRPORT:
573 1.1 cgd if (c >= sp->num_airports)
574 1.1 cgd return ("Unknown airport");
575 1.1 cgd p.new_dir = DIR_FROM_DXDY(sp->airport[c].x - p.xpos,
576 1.1 cgd sp->airport[c].y - p.ypos);
577 1.1 cgd break;
578 1.1 cgd default:
579 1.1 cgd return ("Unknown case in benum! Get help!");
580 1.1 cgd break;
581 1.1 cgd }
582 1.1 cgd return (NULL);
583 1.1 cgd }
584 1.1 cgd
585 1.1 cgd char *
586 1.1 cgd to_dir(c)
587 1.1 cgd {
588 1.1 cgd p.new_dir = dir_no(c);
589 1.1 cgd return (NULL);
590 1.1 cgd }
591 1.1 cgd
592 1.1 cgd char *
593 1.1 cgd rel_dir(c)
594 1.1 cgd {
595 1.1 cgd int angle;
596 1.1 cgd
597 1.1 cgd angle = dir_no(c);
598 1.1 cgd switch (dir) {
599 1.1 cgd case D_LEFT:
600 1.1 cgd p.new_dir = p.dir - angle;
601 1.1 cgd if (p.new_dir < 0)
602 1.1 cgd p.new_dir += MAXDIR;
603 1.1 cgd break;
604 1.1 cgd case D_RIGHT:
605 1.1 cgd p.new_dir = p.dir + angle;
606 1.1 cgd if (p.new_dir >= MAXDIR)
607 1.1 cgd p.new_dir -= MAXDIR;
608 1.1 cgd break;
609 1.1 cgd default:
610 1.1 cgd return ("Bizarre direction in rel_dir! Get help!");
611 1.1 cgd break;
612 1.1 cgd }
613 1.1 cgd return (NULL);
614 1.1 cgd }
615 1.1 cgd
616 1.1 cgd char *
617 1.1 cgd mark(c)
618 1.1 cgd {
619 1.1 cgd if (p.altitude == 0)
620 1.1 cgd return ("Cannot mark planes on the ground");
621 1.1 cgd if (p.status == S_MARKED)
622 1.1 cgd return ("Already marked");
623 1.1 cgd p.status = S_MARKED;
624 1.1 cgd return (NULL);
625 1.1 cgd }
626 1.1 cgd
627 1.1 cgd char *
628 1.1 cgd unmark(c)
629 1.1 cgd {
630 1.1 cgd if (p.altitude == 0)
631 1.1 cgd return ("Cannot unmark planes on the ground");
632 1.1 cgd if (p.status == S_UNMARKED)
633 1.1 cgd return ("Already unmarked");
634 1.1 cgd p.status = S_UNMARKED;
635 1.1 cgd return (NULL);
636 1.1 cgd }
637 1.1 cgd
638 1.1 cgd char *
639 1.1 cgd ignore(c)
640 1.1 cgd {
641 1.1 cgd if (p.altitude == 0)
642 1.1 cgd return ("Cannot ignore planes on the ground");
643 1.1 cgd if (p.status == S_IGNORED)
644 1.1 cgd return ("Already ignored");
645 1.1 cgd p.status = S_IGNORED;
646 1.1 cgd return (NULL);
647 1.1 cgd }
648 1.1 cgd
649 1.1 cgd dir_no(ch)
650 1.1 cgd char ch;
651 1.1 cgd {
652 1.1 cgd int dir;
653 1.1 cgd
654 1.1 cgd switch (ch) {
655 1.1 cgd case 'w': dir = 0; break;
656 1.1 cgd case 'e': dir = 1; break;
657 1.1 cgd case 'd': dir = 2; break;
658 1.1 cgd case 'c': dir = 3; break;
659 1.1 cgd case 'x': dir = 4; break;
660 1.1 cgd case 'z': dir = 5; break;
661 1.1 cgd case 'a': dir = 6; break;
662 1.1 cgd case 'q': dir = 7; break;
663 1.1 cgd default:
664 1.1 cgd fprintf(stderr, "bad character in dir_no\n");
665 1.1 cgd break;
666 1.1 cgd }
667 1.1 cgd return (dir);
668 1.1 cgd }
669