fish/fish.c

   1 /*      $NetBSD: fish.c,v 1.25 2021/05/02 12:24:59 rillig 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 1.25 2021/05/02 12:24:59 rillig 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
  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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 433 instructions(void)
 434 {
 435         int input;
 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 = getchar();
 443         while (getchar() != '\n');
 444         if (input != 'y')
 445                 return;
 446
 447         switch (pid = fork()) {
 448         case 0: /* child */
 449                 if (!isatty(1))
 450                         pager = "cat";
 451                 else {
 452                         if (!(pager = getenv("PAGER")) || (*pager == 0))
 453                                 pager = _PATH_MORE;
 454                 }
 455                 if ((fd = open(_PATH_INSTR, O_RDONLY)) == -1)
 456                         err(1, "open %s", _PATH_INSTR);
 457                 if (dup2(fd, 0) == -1)
 458                         err(1, "dup2");
 459                 (void)execl("/bin/sh", "sh", "-c", pager, (char *) NULL);
 460                 err(1, "exec sh -c %s", pager);
 461                 /*NOTREACHED*/
 462         case -1:
 463                 err(1, "fork");
 464                 /*NOTREACHED*/
 465         default:
 466                 (void)waitpid(pid, &status, 0);
 467                 break;
 468         }
 469         (void)printf("Hit return to continue...\n");
 470         while ((input = getchar()) != EOF && input != '\n');
 471 }
 472
 473 static void
 474 usage(void)
 475 {
 476         (void)fprintf(stderr, "usage: fish [-p]\n");
 477         exit(1);
 478 }