xref: /netbsd/games/fish/fish.c (revision 1252cf5e)
1 /*	$NetBSD: fish.c,v 1.27 2021/07/25 02:00:42 dholland Exp $	*/
2 
3 /*-
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Muffy Barkocy.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #ifndef lint
37 __COPYRIGHT("@(#) Copyright (c) 1990, 1993\
38  The Regents of the University of California.  All rights reserved.");
39 #endif /* not lint */
40 
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "@(#)fish.c	8.1 (Berkeley) 5/31/93";
44 #else
45 __RCSID("$NetBSD: fish.c,v 1.27 2021/07/25 02:00:42 dholland Exp $");
46 #endif
47 #endif /* not lint */
48 
49 #include <sys/types.h>
50 #include <sys/wait.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <unistd.h>
56 #include <string.h>
57 #include <err.h>
58 #include "pathnames.h"
59 
60 #define	RANKS		13
61 #define	HANDSIZE	7
62 #define	CARDS		4
63 #define	TOTCARDS	RANKS * CARDS
64 
65 #define	USER		1
66 #define	COMPUTER	0
67 #define	OTHER(a)	(1 - (a))
68 
69 static const char *const cards[] = {
70 	"A", "2", "3", "4", "5", "6", "7",
71 	"8", "9", "10", "J", "Q", "K", NULL,
72 };
73 #define	PRC(card)	(void)printf(" %s", cards[card])
74 
75 static int promode;
76 static int asked[RANKS], comphand[RANKS], deck[TOTCARDS];
77 static int userasked[RANKS], userhand[RANKS];
78 static int curcard = TOTCARDS;
79 
80 static void chkwinner(int, const int *);
81 static int compmove(void);
82 static int countbooks(const int *);
83 static int countcards(const int *);
84 static int drawcard(int, int *);
85 static int gofish(int, int, int *);
86 static void goodmove(int, int, int *, int *);
87 static void init(void);
88 static void instructions(void);
89 static void printhand(const int *);
90 static void printplayer(int);
91 static int promove(void);
92 static void usage(void) __dead;
93 static int usermove(void);
94 
95 int
main(int argc,char ** argv)96 main(int argc, char **argv)
97 {
98 	int ch, move;
99 
100 	/* Revoke setgid privileges */
101 	setgid(getgid());
102 
103 	while ((ch = getopt(argc, argv, "p")) != -1)
104 		switch(ch) {
105 		case 'p':
106 			promode = 1;
107 			break;
108 		case '?':
109 		default:
110 			usage();
111 		}
112 
113 	instructions();
114 	init();
115 
116 	if (arc4random_uniform(2) == 1) {
117 		printplayer(COMPUTER);
118 		(void)printf("get to start.\n");
119 		goto istart;
120 	}
121 	printplayer(USER);
122 	(void)printf("get to start.\n");
123 
124 	for (;;) {
125 		move = usermove();
126 		if (!comphand[move]) {
127 			if (gofish(move, USER, userhand))
128 				continue;
129 		} else {
130 			goodmove(USER, move, userhand, comphand);
131 			continue;
132 		}
133 
134 istart:		for (;;) {
135 			move = compmove();
136 			if (!userhand[move]) {
137 				if (!gofish(move, COMPUTER, comphand))
138 					break;
139 			} else
140 				goodmove(COMPUTER, move, comphand, userhand);
141 		}
142 	}
143 	/* NOTREACHED */
144 }
145 
146 static int
usermove(void)147 usermove(void)
148 {
149 	int n;
150 	const char *const *p;
151 	char buf[256];
152 
153 	(void)printf("\nYour hand is:");
154 	printhand(userhand);
155 
156 	for (;;) {
157 		(void)printf("You ask me for: ");
158 		(void)fflush(stdout);
159 		if (fgets(buf, sizeof(buf), stdin) == NULL)
160 			exit(0);
161 		if (buf[0] == '\0')
162 			continue;
163 		if (buf[0] == '\n') {
164 			(void)printf("%d cards in my hand, %d in the pool.\n",
165 			    countcards(comphand), curcard);
166 			(void)printf("My books:");
167 			(void)countbooks(comphand);
168 			continue;
169 		}
170 		buf[strlen(buf) - 1] = '\0';
171 		if (!strcasecmp(buf, "p")) {
172 			if (!promode) {
173 				promode = 1;
174 				printf("Entering pro mode.\n");
175 			}
176 			else {
177 				printf("Already in pro mode.\n");
178 			}
179 			continue;
180 		}
181 		if (!strcasecmp(buf, "quit"))
182 			exit(0);
183 		for (p = cards; *p; ++p)
184 			if (!strcasecmp(*p, buf))
185 				break;
186 		if (!*p) {
187 			(void)printf("I don't understand!\n");
188 			continue;
189 		}
190 		n = p - cards;
191 		if (userhand[n] <= 3) {
192 			userasked[n] = 1;
193 			return(n);
194 		}
195 		if (userhand[n] == 4) {
196 			printf("You already have all of those.\n");
197 			continue;
198 		}
199 
200 		if (arc4random_uniform(3) == 1)
201 			(void)printf("You don't have any of those!\n");
202 		else
203 			(void)printf("You don't have any %s's!\n", cards[n]);
204 		if (arc4random_uniform(4) == 1)
205 			(void)printf("No cheating!\n");
206 		(void)printf("Guess again.\n");
207 	}
208 	/* NOTREACHED */
209 }
210 
211 static int
compmove(void)212 compmove(void)
213 {
214 	static int lmove;
215 
216 	if (promode)
217 		lmove = promove();
218 	else {
219 		do {
220 			lmove = (lmove + 1) % RANKS;
221 		} while (!comphand[lmove] || comphand[lmove] == CARDS);
222 	}
223 	asked[lmove] = 1;
224 
225 	(void)printf("I ask you for: %s.\n", cards[lmove]);
226 	return(lmove);
227 }
228 
229 static int
promove(void)230 promove(void)
231 {
232 	int i, max;
233 
234 	for (i = 0; i < RANKS; ++i)
235 		if (userasked[i] &&
236 		    comphand[i] > 0 && comphand[i] < CARDS) {
237 			userasked[i] = 0;
238 			return(i);
239 		}
240 	if (arc4random_uniform(3) == 1) {
241 		for (i = 0;; ++i)
242 			if (comphand[i] && comphand[i] != CARDS) {
243 				max = i;
244 				break;
245 			}
246 		while (++i < RANKS)
247 			if (comphand[i] != CARDS &&
248 			    comphand[i] > comphand[max])
249 				max = i;
250 		return(max);
251 	}
252 	if (arc4random_uniform(1024) == 0723) {
253 		for (i = 0; i < RANKS; ++i)
254 			if (userhand[i] && comphand[i])
255 				return(i);
256 	}
257 	for (;;) {
258 		for (i = 0; i < RANKS; ++i)
259 			if (comphand[i] && comphand[i] != CARDS &&
260 			    !asked[i])
261 				return(i);
262 		for (i = 0; i < RANKS; ++i)
263 			asked[i] = 0;
264 	}
265 	/* NOTREACHED */
266 }
267 
268 static int
drawcard(int player,int * hand)269 drawcard(int player, int *hand)
270 {
271 	int card;
272 
273 	++hand[card = deck[--curcard]];
274 	if (player == USER || hand[card] == CARDS) {
275 		printplayer(player);
276 		(void)printf("drew %s", cards[card]);
277 		if (hand[card] == CARDS) {
278 			(void)printf(" and made a book of %s's!\n",
279 			     cards[card]);
280 			chkwinner(player, hand);
281 		} else
282 			(void)printf(".\n");
283 	}
284 	return(card);
285 }
286 
287 static int
gofish(int askedfor,int player,int * hand)288 gofish(int askedfor, int player, int *hand)
289 {
290 	printplayer(OTHER(player));
291 	(void)printf("say \"GO FISH!\"\n");
292 	if (askedfor == drawcard(player, hand)) {
293 		printplayer(player);
294 		(void)printf("drew the guess!\n");
295 		printplayer(player);
296 		(void)printf("get to ask again!\n");
297 		return(1);
298 	}
299 	return(0);
300 }
301 
302 static void
goodmove(int player,int move,int * hand,int * opphand)303 goodmove(int player, int move, int *hand, int *opphand)
304 {
305 	printplayer(OTHER(player));
306 	(void)printf("have %d %s%s.\n",
307 	    opphand[move], cards[move], opphand[move] == 1 ? "": "'s");
308 
309 	hand[move] += opphand[move];
310 	opphand[move] = 0;
311 
312 	if (hand[move] == CARDS) {
313 		printplayer(player);
314 		(void)printf("made a book of %s's!\n", cards[move]);
315 		chkwinner(player, hand);
316 	}
317 
318 	chkwinner(OTHER(player), opphand);
319 
320 	printplayer(player);
321 	(void)printf("get another guess!\n");
322 }
323 
324 static void
chkwinner(int player,const int * hand)325 chkwinner(int player, const int *hand)
326 {
327 	int cb, i, ub;
328 
329 	for (i = 0; i < RANKS; ++i)
330 		if (hand[i] > 0 && hand[i] < CARDS)
331 			return;
332 	printplayer(player);
333 	(void)printf("don't have any more cards!\n");
334 	(void)printf("My books:");
335 	cb = countbooks(comphand);
336 	(void)printf("Your books:");
337 	ub = countbooks(userhand);
338 	(void)printf("\nI have %d, you have %d.\n", cb, ub);
339 	if (ub > cb) {
340 		(void)printf("\nYou win!!!\n");
341 		if (arc4random_uniform(1024) == 0723)
342 			(void)printf("Cheater, cheater, pumpkin eater!\n");
343 	} else if (cb > ub) {
344 		(void)printf("\nI win!!!\n");
345 		if (arc4random_uniform(1024) == 0723)
346 			(void)printf("Hah!  Stupid peasant!\n");
347 	} else
348 		(void)printf("\nTie!\n");
349 	exit(0);
350 }
351 
352 static void
printplayer(int player)353 printplayer(int player)
354 {
355 	switch (player) {
356 	case COMPUTER:
357 		(void)printf("I ");
358 		break;
359 	case USER:
360 		(void)printf("You ");
361 		break;
362 	}
363 }
364 
365 static void
printhand(const int * hand)366 printhand(const int *hand)
367 {
368 	int book, i, j;
369 
370 	for (book = i = 0; i < RANKS; i++)
371 		if (hand[i] < CARDS)
372 			for (j = hand[i]; --j >= 0;)
373 				PRC(i);
374 		else
375 			++book;
376 	if (book) {
377 		(void)printf(" + Book%s of", book > 1 ? "s" : "");
378 		for (i = 0; i < RANKS; i++)
379 			if (hand[i] == CARDS)
380 				PRC(i);
381 	}
382 	(void)putchar('\n');
383 }
384 
385 static int
countcards(const int * hand)386 countcards(const int *hand)
387 {
388 	int i, count;
389 
390 	for (count = i = 0; i < RANKS; i++)
391 		count += *hand++;
392 	return(count);
393 }
394 
395 static int
countbooks(const int * hand)396 countbooks(const int *hand)
397 {
398 	int i, count;
399 
400 	for (count = i = 0; i < RANKS; i++)
401 		if (hand[i] == CARDS) {
402 			++count;
403 			PRC(i);
404 		}
405 	if (!count)
406 		(void)printf(" none");
407 	(void)putchar('\n');
408 	return(count);
409 }
410 
411 static void
init(void)412 init(void)
413 {
414 	int i, j, temp;
415 
416 	for (i = 0; i < TOTCARDS; ++i)
417 		deck[i] = i % RANKS;
418 	for (i = 0; i < TOTCARDS - 1; ++i) {
419 		j = arc4random_uniform(TOTCARDS-i);
420 		if (j == 0)
421 			continue;
422 		temp = deck[i];
423 		deck[i] = deck[i+j];
424 		deck[i+j] = temp;
425 	}
426 	for (i = 0; i < HANDSIZE; ++i) {
427 		++userhand[deck[--curcard]];
428 		++comphand[deck[--curcard]];
429 	}
430 }
431 
432 static void
instructions(void)433 instructions(void)
434 {
435 	int input, c;
436 	pid_t pid;
437 	int fd;
438 	const char *pager;
439 	int status;
440 
441 	(void)printf("Would you like instructions (y or n)? ");
442 	input = c = getchar();
443 	while (c != '\n') {
444 		c = getchar();
445 		if (c == EOF) {
446 			exit(1);
447 		}
448 	}
449 	if (input != 'y')
450 		return;
451 
452 	switch (pid = fork()) {
453 	case 0: /* child */
454 		if (!isatty(1))
455 			pager = "cat";
456 		else {
457 			if (!(pager = getenv("PAGER")) || (*pager == 0))
458 				pager = _PATH_MORE;
459 		}
460 		if ((fd = open(_PATH_INSTR, O_RDONLY)) == -1)
461 			err(1, "open %s", _PATH_INSTR);
462 		if (dup2(fd, 0) == -1)
463 			err(1, "dup2");
464 		(void)execl("/bin/sh", "sh", "-c", pager, (char *) NULL);
465 		err(1, "exec sh -c %s", pager);
466 		/*NOTREACHED*/
467 	case -1:
468 		err(1, "fork");
469 		/*NOTREACHED*/
470 	default:
471 		(void)waitpid(pid, &status, 0);
472 		break;
473 	}
474 	(void)printf("Hit return to continue...\n");
475 	while ((input = getchar()) != EOF && input != '\n');
476 }
477 
478 static void
usage(void)479 usage(void)
480 {
481 	(void)fprintf(stderr, "usage: fish [-p]\n");
482 	exit(1);
483 }
484