xref: /dragonfly/games/wump/wump.c (revision 19fe1c42)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Dave Taylor, of Intuitive Systems.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  * @(#) Copyright (c) 1989, 1993 The Regents of the University of California.  All rights reserved.
38  * @(#)wump.c	8.1 (Berkeley) 5/31/93
39  * $FreeBSD: src/games/wump/wump.c,v 1.13.2.1 2000/08/17 06:24:54 jhb Exp $
40  * $DragonFly: src/games/wump/wump.c,v 1.6 2007/04/18 18:32:12 swildner Exp $
41  */
42 
43 /*
44  * A very new version of the age old favorite Hunt-The-Wumpus game that has
45  * been a part of the BSD distribution of Unix for longer than us old folk
46  * would care to remember.
47  */
48 
49 #include <err.h>
50 #include <sys/types.h>
51 #include <sys/file.h>
52 #include <sys/wait.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include "pathnames.h"
58 
59 /* some defines to spec out what our wumpus cave should look like */
60 
61 #define	MAX_ARROW_SHOT_DISTANCE	6		/* +1 for '0' stopper */
62 #define	MAX_LINKS_IN_ROOM	25		/* a complex cave */
63 
64 #define	MAX_ROOMS_IN_CAVE	250
65 #define	ROOMS_IN_CAVE		20
66 #define	MIN_ROOMS_IN_CAVE	10
67 
68 #define	LINKS_IN_ROOM		3
69 #define	NUMBER_OF_ARROWS	5
70 #define	PIT_COUNT		3
71 #define	BAT_COUNT		3
72 
73 #define	EASY			1		/* levels of play */
74 #define	HARD			2
75 
76 /* some macro definitions for cleaner output */
77 
78 #define	plural(n)	(n == 1 ? "" : "s")
79 
80 /* simple cave data structure; +1 so we can index from '1' not '0' */
81 struct room_record {
82 	int tunnel[MAX_LINKS_IN_ROOM];
83 	int has_a_pit, has_a_bat;
84 } cave[MAX_ROOMS_IN_CAVE+1];
85 
86 /*
87  * global variables so we can keep track of where the player is, how
88  * many arrows they still have, where el wumpo is, and so on...
89  */
90 int player_loc = -1;			/* player location */
91 int wumpus_loc = -1;			/* The Bad Guy location */
92 int level = EASY;			/* level of play */
93 int arrows_left;			/* arrows unshot */
94 
95 #ifdef DEBUG
96 int debug = 0;
97 #endif
98 
99 int pit_num = PIT_COUNT;		/* # pits in cave */
100 int bat_num = BAT_COUNT;		/* # bats */
101 int room_num = ROOMS_IN_CAVE;		/* # rooms in cave */
102 int link_num = LINKS_IN_ROOM;		/* links per room  */
103 int arrow_num = NUMBER_OF_ARROWS;	/* arrow inventory */
104 
105 char answer[20];			/* user input */
106 
107 int 	bats_nearby(void);
108 void 	cave_init(void);
109 void 	clear_things_in_cave(void);
110 void 	display_room_stats (void);
111 int 	getans (const char *prompt);
112 void 	initialize_things_in_cave(void);
113 void 	instructions(void);
114 int 	int_compare (const void *va, const void *vb);
115 void 	jump(int where);
116 void 	kill_wump(void);
117 int 	move_to (char *room_number);
118 void 	move_wump(void);
119 void 	no_arrows(void);
120 void 	pit_kill(void);
121 int 	pit_nearby(void);
122 void 	pit_survive(void);
123 int 	shoot (char *room_list);
124 void 	shoot_self(void);
125 int 	take_action(void);
126 void 	usage(void);
127 void 	wump_kill(void);
128 int 	wump_nearby(void);
129 
130 int
131 main(int argc, char **argv)
132 {
133 	int c;
134 
135 	/* revoke */
136 	setgid(getgid());
137 
138 #ifdef DEBUG
139 	while ((c = getopt(argc, argv, "a:b:hp:r:t:d")) != -1)
140 #else
141 	while ((c = getopt(argc, argv, "a:b:hp:r:t:")) != -1)
142 #endif
143 		switch (c) {
144 		case 'a':
145 			arrow_num = atoi(optarg);
146 			break;
147 		case 'b':
148 			bat_num = atoi(optarg);
149 			break;
150 #ifdef DEBUG
151 		case 'd':
152 			debug = 1;
153 			break;
154 #endif
155 		case 'h':
156 			level = HARD;
157 			break;
158 		case 'p':
159 			pit_num = atoi(optarg);
160 			break;
161 		case 'r':
162 			room_num = atoi(optarg);
163 			if (room_num < MIN_ROOMS_IN_CAVE) {
164 				(void)fprintf(stderr,
165 	"No self-respecting wumpus would live in such a small cave!\n");
166 				exit(1);
167 			}
168 			if (room_num > MAX_ROOMS_IN_CAVE) {
169 				(void)fprintf(stderr,
170 	"Even wumpii can't furnish caves that large!\n");
171 				exit(1);
172 			}
173 			break;
174 		case 't':
175 			link_num = atoi(optarg);
176 			if (link_num < 2) {
177 				(void)fprintf(stderr,
178 	"Wumpii like extra doors in their caves!\n");
179 				exit(1);
180 			}
181 			break;
182 		case '?':
183 		default:
184 			usage();
185 	}
186 
187 	if (link_num > MAX_LINKS_IN_ROOM ||
188 	    link_num > room_num - (room_num / 4)) {
189 		(void)fprintf(stderr,
190 "Too many tunnels!  The cave collapsed!\n(Fortunately, the wumpus escaped!)\n");
191 		exit(1);
192 	}
193 
194 	if (level == HARD) {
195 		bat_num += ((random() % (room_num / 2)) + 1);
196 		pit_num += ((random() % (room_num / 2)) + 1);
197 	}
198 
199 	if (bat_num > room_num / 2) {
200 		(void)fprintf(stderr,
201 "The wumpus refused to enter the cave, claiming it was too crowded!\n");
202 		exit(1);
203 	}
204 
205 	if (pit_num > room_num / 2) {
206 		(void)fprintf(stderr,
207 "The wumpus refused to enter the cave, claiming it was too dangerous!\n");
208 		exit(1);
209 	}
210 
211 	instructions();
212 	cave_init();
213 
214 	/* and we're OFF!  da dum, da dum, da dum, da dum... */
215 	(void)printf(
216 "\nYou're in a cave with %d rooms and %d tunnels leading from each room.\n\
217 There are %d bat%s and %d pit%s scattered throughout the cave, and your\n\
218 quiver holds %d custom super anti-evil Wumpus arrows.  Good luck.\n",
219 	    room_num, link_num, bat_num, plural(bat_num), pit_num,
220 	    plural(pit_num), arrow_num);
221 
222 	for (;;) {
223 		initialize_things_in_cave();
224 		arrows_left = arrow_num;
225 		do {
226 			display_room_stats();
227 			(void)printf("Move or shoot? (m-s) ");
228 			(void)fflush(stdout);
229 			if (!fgets(answer, sizeof(answer), stdin))
230 				break;
231 		} while (!take_action());
232 
233 		if (!getans("\nCare to play another game? (y-n) "))
234 			exit(0);
235 		if (getans("In the same cave? (y-n) "))
236 			clear_things_in_cave();
237 		else
238 			cave_init();
239 	}
240 	/* NOTREACHED */
241 	exit(EXIT_SUCCESS);
242 }
243 
244 void
245 display_room_stats(void)
246 {
247 	int i;
248 
249 	/*
250 	 * Routine will explain what's going on with the current room, as well
251 	 * as describe whether there are pits, bats, & wumpii nearby.  It's
252 	 * all pretty mindless, really.
253 	 */
254 	(void)printf(
255 "\nYou are in room %d of the cave, and have %d arrow%s left.\n",
256 	    player_loc, arrows_left, plural(arrows_left));
257 
258 	if (bats_nearby())
259 		(void)printf("*rustle* *rustle* (must be bats nearby)\n");
260 	if (pit_nearby())
261 		(void)printf("*whoosh* (I feel a draft from some pits).\n");
262 	if (wump_nearby())
263 		(void)printf("*sniff* (I can smell the evil Wumpus nearby!)\n");
264 
265 	(void)printf("There are tunnels to rooms %d, ",
266 	   cave[player_loc].tunnel[0]);
267 
268 	for (i = 1; i < link_num - 1; i++)
269 		if (cave[player_loc].tunnel[i] <= room_num)
270 			(void)printf("%d, ", cave[player_loc].tunnel[i]);
271 	(void)printf("and %d.\n", cave[player_loc].tunnel[link_num - 1]);
272 }
273 
274 int
275 take_action(void)
276 {
277 	/*
278 	 * Do the action specified by the player, either 'm'ove, 's'hoot
279 	 * or something exceptionally bizarre and strange!  Returns 1
280 	 * iff the player died during this turn, otherwise returns 0.
281 	 */
282 	switch (*answer) {
283 		case 'M':
284 		case 'm':			/* move */
285 			return(move_to(answer + 1));
286 		case 'S':
287 		case 's':			/* shoot */
288 			return(shoot(answer + 1));
289 		case 'Q':
290 		case 'q':
291 		case 'x':
292 			exit(0);
293 		case '\n':
294 			return(0);
295 		}
296 	if (random() % 15 == 1)
297 		(void)printf("Que pasa?\n");
298 	else
299 		(void)printf("I don't understand!\n");
300 	return(0);
301 }
302 
303 int
304 move_to(char *room_number)
305 {
306 	int i, just_moved_by_bats, next_room, tunnel_available;
307 
308 	/*
309 	 * This is responsible for moving the player into another room in the
310 	 * cave as per their directions.  If room_number is a null string,
311 	 * then we'll prompt the user for the next room to go into.   Once
312 	 * we've moved into the room, we'll check for things like bats, pits,
313 	 * and so on.  This routine returns 1 if something occurs that kills
314 	 * the player and 0 otherwise...
315 	 */
316 	tunnel_available = just_moved_by_bats = 0;
317 	next_room = atoi(room_number);
318 
319 	/* crap for magic tunnels */
320 	if (next_room == room_num + 1 &&
321 	    cave[player_loc].tunnel[link_num-1] != next_room)
322 		++next_room;
323 
324 	while (next_room < 1 || next_room > room_num + 1) {
325 		if (next_room < 0 && next_room != -1)
326 (void)printf("Sorry, but we're constrained to a semi-Euclidean cave!\n");
327 		if (next_room > room_num + 1)
328 (void)printf("What?  The cave surely isn't quite that big!\n");
329 		if (next_room == room_num + 1 &&
330 		    cave[player_loc].tunnel[link_num-1] != next_room) {
331 			(void)printf("What?  The cave isn't that big!\n");
332 			++next_room;
333 		}
334 		(void)printf("To which room do you wish to move? ");
335 		(void)fflush(stdout);
336 		if (!fgets(answer, sizeof(answer), stdin))
337 			return(1);
338 		next_room = atoi(answer);
339 	}
340 
341 	/* now let's see if we can move to that room or not */
342 	tunnel_available = 0;
343 	for (i = 0; i < link_num; i++)
344 		if (cave[player_loc].tunnel[i] == next_room)
345 			tunnel_available = 1;
346 
347 	if (!tunnel_available) {
348 		(void)printf("*Oof!*  (You hit the wall)\n");
349 		if (random() % 6 == 1) {
350 (void)printf("Your colorful comments awaken the wumpus!\n");
351 			move_wump();
352 			if (wumpus_loc == player_loc) {
353 				wump_kill();
354 				return(1);
355 			}
356 		}
357 		return(0);
358 	}
359 
360 	/* now let's move into that room and check it out for dangers */
361 	if (next_room == room_num + 1)
362 		jump(next_room = (random() % room_num) + 1);
363 
364 	player_loc = next_room;
365 	for (;;) {
366 		if (next_room == wumpus_loc) {		/* uh oh... */
367 			wump_kill();
368 			return(1);
369 		}
370 		if (cave[next_room].has_a_pit) {
371 			if (random() % 12 < 2) {
372 				pit_survive();
373 				return(0);
374 			} else {
375 				pit_kill();
376 				return(1);
377 			}
378 		}
379 
380 		if (cave[next_room].has_a_bat) {
381 			(void)printf(
382 "*flap*  *flap*  *flap*  (humongous bats pick you up and move you%s!)\n",
383 			    just_moved_by_bats ? " again": "");
384 			next_room = player_loc = (random() % room_num) + 1;
385 			just_moved_by_bats = 1;
386 		}
387 
388 		else
389 			break;
390 	}
391 	return(0);
392 }
393 
394 int
395 shoot(char *room_list)
396 {
397 	int chance, next, roomcnt;
398 	int j, arrow_location, wumplink, ok;
399 	char *p;
400 
401 	/*
402 	 * Implement shooting arrows.  Arrows are shot by the player indicating
403 	 * a space-separated list of rooms that the arrow should pass through;
404 	 * if any of the rooms they specify are not accessible via tunnel from
405 	 * the room the arrow is in, it will instead fly randomly into another
406 	 * room.  If the player hits the wumpus, this routine will indicate
407 	 * such.  If it misses, this routine will *move* the wumpus one room.
408 	 * If it's the last arrow, the player then dies...  Returns 1 if the
409 	 * player has won or died, 0 if nothing has happened.
410 	 */
411 	arrow_location = player_loc;
412 	for (roomcnt = 1;; ++roomcnt, room_list = NULL) {
413 		if (!(p = strtok(room_list, " \t\n"))) {
414 			if (roomcnt == 1) {
415 				(void)printf(
416 			"The arrow falls to the ground at your feet!\n");
417 				return(0);
418 			} else
419 				break;
420 		}
421 		if (roomcnt > 5)  {
422 			(void)printf(
423 "The arrow wavers in its flight and and can go no further!\n");
424 			break;
425 		}
426 		next = atoi(p);
427 		for (j = 0, ok = 0; j < link_num; j++)
428 			if (cave[arrow_location].tunnel[j] == next)
429 				ok = 1;
430 
431 		if (ok) {
432 			if (next > room_num) {
433 				(void)printf(
434 "A faint gleam tells you the arrow has gone through a magic tunnel!\n");
435 				arrow_location = (random() % room_num) + 1;
436 			} else
437 				arrow_location = next;
438 		} else {
439 			wumplink = (random() % link_num);
440 			if (wumplink == player_loc)
441 				(void)printf(
442 "*thunk*  The arrow can't find a way from %d to %d and flys back into\n\
443 your room!\n",
444 				    arrow_location, next);
445 			else if (cave[arrow_location].tunnel[wumplink] > room_num)
446 				(void)printf(
447 "*thunk*  The arrow flys randomly into a magic tunnel, thence into\n\
448 room %d!\n",
449 				    cave[arrow_location].tunnel[wumplink]);
450 			else
451 				(void)printf(
452 "*thunk*  The arrow can't find a way from %d to %d and flys randomly\n\
453 into room %d!\n",
454 				    arrow_location, next,
455 				    cave[arrow_location].tunnel[wumplink]);
456 			arrow_location = cave[arrow_location].tunnel[wumplink];
457 			break;
458 		}
459 		chance = random() % 10;
460 		if (roomcnt == 3 && chance < 2) {
461 			(void)printf(
462 "Your bowstring breaks!  *twaaaaaang*\n\
463 The arrow is weakly shot and can go no further!\n");
464 			break;
465 		} else if (roomcnt == 4 && chance < 6) {
466 			(void)printf(
467 "The arrow wavers in its flight and and can go no further!\n");
468 			break;
469 		}
470 	}
471 
472 	/*
473 	 * now we've gotten into the new room let us see if El Wumpo is
474 	 * in the same room ... if so we've a HIT and the player WON!
475 	 */
476 	if (arrow_location == wumpus_loc) {
477 		kill_wump();
478 		return(1);
479 	}
480 
481 	if (arrow_location == player_loc) {
482 		shoot_self();
483 		return(1);
484 	}
485 
486 	if (!--arrows_left) {
487 		no_arrows();
488 		return(1);
489 	}
490 
491 	{
492 		/* each time you shoot, it's more likely the wumpus moves */
493 		static int lastchance = 2;
494 
495 		if (random() % level == EASY ? 12 : 9 < (lastchance += 2)) {
496 			move_wump();
497 			if (wumpus_loc == player_loc)
498 				wump_kill();
499 			lastchance = random() % 3;
500 
501 		}
502 	}
503 	return(0);
504 }
505 
506 void
507 cave_init(void)
508 {
509 	int i, j, k, wumplink;
510 	int delta;
511 
512 	/*
513 	 * This does most of the interesting work in this program actually!
514 	 * In this routine we'll initialize the Wumpus cave to have all rooms
515 	 * linking to all others by stepping through our data structure once,
516 	 * recording all forward links and backwards links too.  The parallel
517 	 * "linkcount" data structure ensures that no room ends up with more
518 	 * than three links, regardless of the quality of the random number
519 	 * generator that we're using.
520 	 */
521 	srandomdev();
522 
523 	/* initialize the cave first off. */
524 	for (i = 1; i <= room_num; ++i)
525 		for (j = 0; j < link_num ; ++j)
526 			cave[i].tunnel[j] = -1;
527 
528 	/* choose a random 'hop' delta for our guaranteed link */
529 	while (!(delta = random() % room_num));
530 
531 	for (i = 1; i <= room_num; ++i) {
532 		wumplink = ((i + delta) % room_num) + 1;	/* connection */
533 		cave[i].tunnel[0] = wumplink;			/* forw link */
534 		cave[wumplink].tunnel[1] = i;			/* back link */
535 	}
536 	/* now fill in the rest of the cave with random connections */
537 	for (i = 1; i <= room_num; i++)
538 		for (j = 2; j < link_num ; j++) {
539 			if (cave[i].tunnel[j] != -1)
540 				continue;
541 try_again:		wumplink = (random() % room_num) + 1;
542 			/* skip duplicates */
543 			for (k = 0; k < j; k++)
544 				if (cave[i].tunnel[k] == wumplink)
545 					goto try_again;
546 			cave[i].tunnel[j] = wumplink;
547 			if (random() % 2 == 1)
548 				continue;
549 			for (k = 0; k < link_num; ++k) {
550 				/* if duplicate, skip it */
551 				if (cave[wumplink].tunnel[k] == i)
552 					k = link_num;
553 
554 				/* if open link, use it, force exit */
555 				if (cave[wumplink].tunnel[k] == -1) {
556 					cave[wumplink].tunnel[k] = i;
557 					k = link_num;
558 				}
559 			}
560 		}
561 	/*
562 	 * now that we're done, sort the tunnels in each of the rooms to
563 	 * make it easier on the intrepid adventurer.
564 	 */
565 	for (i = 1; i <= room_num; ++i)
566 		qsort(cave[i].tunnel, (u_int)link_num,
567 		    sizeof(cave[i].tunnel[0]), int_compare);
568 
569 #ifdef DEBUG
570 	if (debug)
571 		for (i = 1; i <= room_num; ++i) {
572 			(void)printf("<room %d  has tunnels to ", i);
573 			for (j = 0; j < link_num; ++j)
574 				(void)printf("%d ", cave[i].tunnel[j]);
575 			(void)printf(">\n");
576 		}
577 #endif
578 }
579 
580 void
581 clear_things_in_cave(void)
582 {
583 	int i;
584 
585 	/*
586 	 * remove bats and pits from the current cave in preparation for us
587 	 * adding new ones via the initialize_things_in_cave() routines.
588 	 */
589 	for (i = 1; i <= room_num; ++i)
590 		cave[i].has_a_bat = cave[i].has_a_pit = 0;
591 }
592 
593 void
594 initialize_things_in_cave(void)
595 {
596 	int i, loc;
597 
598 	/* place some bats, pits, the wumpus, and the player. */
599 	for (i = 0; i < bat_num; ++i) {
600 		do {
601 			loc = (random() % room_num) + 1;
602 		} while (cave[loc].has_a_bat);
603 		cave[loc].has_a_bat = 1;
604 #ifdef DEBUG
605 		if (debug)
606 			(void)printf("<bat in room %d>\n", loc);
607 #endif
608 	}
609 
610 	for (i = 0; i < pit_num; ++i) {
611 		do {
612 			loc = (random() % room_num) + 1;
613 		} while (cave[loc].has_a_pit && cave[loc].has_a_bat);
614 		cave[loc].has_a_pit = 1;
615 #ifdef DEBUG
616 		if (debug)
617 			(void)printf("<pit in room %d>\n", loc);
618 #endif
619 	}
620 
621 	wumpus_loc = (random() % room_num) + 1;
622 #ifdef DEBUG
623 	if (debug)
624 		(void)printf("<wumpus in room %d>\n", loc);
625 #endif
626 
627 	do {
628 		player_loc = (random() % room_num) + 1;
629 	} while (player_loc == wumpus_loc || (level == HARD ?
630 	    (link_num / room_num < 0.4 ? wump_nearby() : 0) : 0));
631 }
632 
633 int
634 getans(const char *prompt)
635 {
636 	char buf[20];
637 
638 	/*
639 	 * simple routine to ask the yes/no question specified until the user
640 	 * answers yes or no, then return 1 if they said 'yes' and 0 if they
641 	 * answered 'no'.
642 	 */
643 	for (;;) {
644 		(void)printf("%s", prompt);
645 		(void)fflush(stdout);
646 		if (!fgets(buf, sizeof(buf), stdin))
647 			return(0);
648 		if (*buf == 'N' || *buf == 'n')
649 			return(0);
650 		if (*buf == 'Y' || *buf == 'y')
651 			return(1);
652 		(void)printf(
653 "I don't understand your answer; please enter 'y' or 'n'!\n");
654 	}
655 	/* NOTREACHED */
656 }
657 
658 int
659 bats_nearby(void)
660 {
661 	int i;
662 
663 	/* check for bats in the immediate vicinity */
664 	for (i = 0; i < link_num; ++i)
665 		if (cave[cave[player_loc].tunnel[i]].has_a_bat)
666 			return(1);
667 	return(0);
668 }
669 
670 int
671 pit_nearby(void)
672 {
673 	int i;
674 
675 	/* check for pits in the immediate vicinity */
676 	for (i = 0; i < link_num; ++i)
677 		if (cave[cave[player_loc].tunnel[i]].has_a_pit)
678 			return(1);
679 	return(0);
680 }
681 
682 int
683 wump_nearby(void)
684 {
685 	int i, j;
686 
687 	/* check for a wumpus within TWO caves of where we are */
688 	for (i = 0; i < link_num; ++i) {
689 		if (cave[player_loc].tunnel[i] == wumpus_loc)
690 			return(1);
691 		for (j = 0; j < link_num; ++j)
692 			if (cave[cave[player_loc].tunnel[i]].tunnel[j] ==
693 			    wumpus_loc)
694 				return(1);
695 	}
696 	return(0);
697 }
698 
699 void
700 move_wump(void)
701 {
702 	wumpus_loc = cave[wumpus_loc].tunnel[random() % link_num];
703 }
704 
705 int
706 int_compare(const void *va, const void *vb)
707 {
708 	const int	*a, *b;
709 
710 	a = (const int *)va;
711 	b = (const int *)vb;
712 
713 	return(a < b ? -1 : 1);
714 }
715 
716 void
717 instructions(void)
718 {
719 	const char *pager;
720 	pid_t pid;
721 	int status;
722 	int fd;
723 
724 	/*
725 	 * read the instructions file, if needed, and show the user how to
726 	 * play this game!
727 	 */
728 	if (!getans("Instructions? (y-n) "))
729 		return;
730 
731 	if (access(_PATH_WUMPINFO, R_OK)) {
732 		(void)printf(
733 "Sorry, but the instruction file seems to have disappeared in a\n\
734 puff of greasy black smoke! (poof)\n");
735 		return;
736 	}
737 
738 	if (!isatty(1))
739 		pager = "cat";
740 	else {
741 		if (!(pager = getenv("PAGER")) || (*pager == 0))
742 			pager = _PATH_PAGER;
743 	}
744 	switch (pid = fork()) {
745 	case 0: /* child */
746 		if ((fd = open(_PATH_WUMPINFO, O_RDONLY)) == -1)
747 			err(1, "open %s", _PATH_WUMPINFO);
748 		if (dup2(fd, 0) == -1)
749 			err(1, "dup2");
750 		(void)execl("/bin/sh", "sh", "-c", pager, (char *) NULL);
751 		err(1, "exec sh -c %s", pager);
752 	case -1:
753 		err(1, "fork");
754 	default:
755 		(void)waitpid(pid, &status, 0);
756 		break;
757 	}
758 }
759 
760 void
761 usage(void)
762 {
763 	(void)fprintf(stderr,
764 "usage: wump [-h] [-a arrows] [-b bats] [-p pits] [-r rooms] [-t tunnels]\n");
765 	exit(1);
766 }
767 
768 /* messages */
769 
770 void
771 wump_kill(void)
772 {
773 	(void)printf(
774 "*ROAR* *chomp* *snurfle* *chomp*!\n\
775 Much to the delight of the Wumpus, you walked right into his mouth,\n\
776 making you one of the easiest dinners he's ever had!  For you, however,\n\
777 it's a rather unpleasant death.  The only good thing is that it's been\n\
778 so long since the evil Wumpus cleaned his teeth that you immediately\n\
779 passed out from the stench!\n");
780 }
781 
782 void
783 kill_wump(void)
784 {
785 	(void)printf(
786 "*thwock!* *groan* *crash*\n\n\
787 A horrible roar fills the cave, and you realize, with a smile, that you\n\
788 have slain the evil Wumpus and won the game!  You don't want to tarry for\n\
789 long, however, because not only is the Wumpus famous, but the stench of\n\
790 dead Wumpus is also quite well known, a stench plenty enough to slay the\n\
791 mightiest adventurer at a single whiff!!\n");
792 }
793 
794 void
795 no_arrows(void)
796 {
797 	(void)printf(
798 "\nYou turn and look at your quiver, and realize with a sinking feeling\n\
799 that you've just shot your last arrow (figuratively, too).  Sensing this\n\
800 with its psychic powers, the evil Wumpus rampagees through the cave, finds\n\
801 you, and with a mighty *ROAR* eats you alive!\n");
802 }
803 
804 void
805 shoot_self(void)
806 {
807 	(void)printf(
808 "\n*Thwack!*  A sudden piercing feeling informs you that the ricochet\n\
809 of your wild arrow has resulted in it wedging in your side, causing\n\
810 extreme agony.  The evil Wumpus, with its psychic powers, realizes this\n\
811 and immediately rushes to your side, not to help, alas, but to EAT YOU!\n\
812 (*CHOMP*)\n");
813 }
814 
815 void
816 jump(int where)
817 {
818 	(void)printf(
819 "\nWith a jaunty step you enter the magic tunnel.  As you do, you\n\
820 notice that the walls are shimmering and glowing.  Suddenly you feel\n\
821 a very curious, warm sensation and find yourself in room %d!!\n", where);
822 }
823 
824 void
825 pit_kill(void)
826 {
827 	(void)printf(
828 "*AAAUUUUGGGGGHHHHHhhhhhhhhhh...*\n\
829 The whistling sound and updraft as you walked into this room of the\n\
830 cave apparently wasn't enough to clue you in to the presence of the\n\
831 bottomless pit.  You have a lot of time to reflect on this error as\n\
832 you fall many miles to the core of the earth.  Look on the bright side;\n\
833 you can at least find out if Jules Verne was right...\n");
834 }
835 
836 void
837 pit_survive(void)
838 {
839 	(void)printf(
840 "Without conscious thought you grab for the side of the cave and manage\n\
841 to grasp onto a rocky outcrop.  Beneath your feet stretches the limitless\n\
842 depths of a bottomless pit!  Rock crumbles beneath your feet!\n");
843 }
844