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tetris.c revision 1.17 
      1 /*	$NetBSD: tetris.c,v 1.17 2004/01/27 20:30:30 jsm Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1992, 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  * Chris Torek and Darren F. Provine.
      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  *	@(#)tetris.c	8.1 (Berkeley) 5/31/93
     35  */
     36 
     37 #include <sys/cdefs.h>
     38 #ifndef lint
     39 __COPYRIGHT("@(#) Copyright (c) 1992, 1993\n\
     40 	The Regents of the University of California.  All rights reserved.\n");
     41 #endif /* not lint */
     42 
     43 /*
     44  * Tetris (or however it is spelled).
     45  */
     46 
     47 #include <sys/time.h>
     48 
     49 #include <err.h>
     50 #include <fcntl.h>
     51 #include <signal.h>
     52 #include <stdio.h>
     53 #include <stdlib.h>
     54 #include <string.h>
     55 #include <unistd.h>
     56 
     57 #include "input.h"
     58 #include "scores.h"
     59 #include "screen.h"
     60 #include "tetris.h"
     61 
     62 cell	board[B_SIZE];		/* 1 => occupied, 0 => empty */
     63 
     64 int	Rows, Cols;		/* current screen size */
     65 
     66 const struct shape *curshape;
     67 const struct shape *nextshape;
     68 
     69 long	fallrate;		/* less than 1 million; smaller => faster */
     70 
     71 int	score;			/* the obvious thing */
     72 gid_t	gid, egid;
     73 
     74 char	key_msg[100];
     75 int	showpreview;
     76 
     77 static	void	elide(void);
     78 static	void	setup_board(void);
     79 	int	main(int, char **);
     80 	void	onintr(int) __attribute__((__noreturn__));
     81 	void	usage(void) __attribute__((__noreturn__));
     82 
     83 /*
     84  * Set up the initial board.  The bottom display row is completely set,
     85  * along with another (hidden) row underneath that.  Also, the left and
     86  * right edges are set.
     87  */
     88 static void
     89 setup_board()
     90 {
     91 	int i;
     92 	cell *p;
     93 
     94 	p = board;
     95 	for (i = B_SIZE; i; i--)
     96 		*p++ = i <= (2 * B_COLS) || (i % B_COLS) < 2;
     97 }
     98 
     99 /*
    100  * Elide any full active rows.
    101  */
    102 static void
    103 elide()
    104 {
    105 	int i, j, base;
    106 	cell *p;
    107 
    108 	for (i = A_FIRST; i < A_LAST; i++) {
    109 		base = i * B_COLS + 1;
    110 		p = &board[base];
    111 		for (j = B_COLS - 2; *p++ != 0;) {
    112 			if (--j <= 0) {
    113 				/* this row is to be elided */
    114 				memset(&board[base], 0, B_COLS - 2);
    115 				scr_update();
    116 				tsleep();
    117 				while (--base != 0)
    118 					board[base + B_COLS] = board[base];
    119 				scr_update();
    120 				tsleep();
    121 				break;
    122 			}
    123 		}
    124 	}
    125 }
    126 
    127 int
    128 main(argc, argv)
    129 	int argc;
    130 	char *argv[];
    131 {
    132 	int pos, c;
    133 	const char *keys;
    134 	int level = 2;
    135 	char key_write[6][10];
    136 	int ch, i, j;
    137 	int fd;
    138 
    139 	gid = getgid();
    140 	egid = getegid();
    141 	setegid(gid);
    142 
    143 	fd = open("/dev/null", O_RDONLY);
    144 	if (fd < 3)
    145 		exit(1);
    146 	close(fd);
    147 
    148 	keys = "jkl pq";
    149 
    150 	while ((ch = getopt(argc, argv, "k:l:ps")) != -1)
    151 		switch(ch) {
    152 		case 'k':
    153 			if (strlen(keys = optarg) != 6)
    154 				usage();
    155 			break;
    156 		case 'l':
    157 			level = atoi(optarg);
    158 			if (level < MINLEVEL || level > MAXLEVEL) {
    159 				errx(1, "level must be from %d to %d",
    160 				     MINLEVEL, MAXLEVEL);
    161 			}
    162 			break;
    163 		case 'p':
    164 			showpreview = 1;
    165 			break;
    166 		case 's':
    167 			showscores(0);
    168 			exit(0);
    169 		case '?':
    170 		default:
    171 			usage();
    172 		}
    173 
    174 	argc -= optind;
    175 	argv += optind;
    176 
    177 	if (argc)
    178 		usage();
    179 
    180 	fallrate = 1000000 / level;
    181 
    182 	for (i = 0; i <= 5; i++) {
    183 		for (j = i+1; j <= 5; j++) {
    184 			if (keys[i] == keys[j]) {
    185 				errx(1, "duplicate command keys specified.");
    186 			}
    187 		}
    188 		if (keys[i] == ' ')
    189 			strcpy(key_write[i], "<space>");
    190 		else {
    191 			key_write[i][0] = keys[i];
    192 			key_write[i][1] = '\0';
    193 		}
    194 	}
    195 
    196 	sprintf(key_msg,
    197 "%s - left   %s - rotate   %s - right   %s - drop   %s - pause   %s - quit",
    198 		key_write[0], key_write[1], key_write[2], key_write[3],
    199 		key_write[4], key_write[5]);
    200 
    201 	(void)signal(SIGINT, onintr);
    202 	scr_init();
    203 	setup_board();
    204 
    205 	srandom(getpid());
    206 	scr_set();
    207 
    208 	pos = A_FIRST*B_COLS + (B_COLS/2)-1;
    209 	nextshape = randshape();
    210 	curshape = randshape();
    211 
    212 	scr_msg(key_msg, 1);
    213 
    214 	for (;;) {
    215 		place(curshape, pos, 1);
    216 		scr_update();
    217 		place(curshape, pos, 0);
    218 		c = tgetchar();
    219 		if (c < 0) {
    220 			/*
    221 			 * Timeout.  Move down if possible.
    222 			 */
    223 			if (fits_in(curshape, pos + B_COLS)) {
    224 				pos += B_COLS;
    225 				continue;
    226 			}
    227 
    228 			/*
    229 			 * Put up the current shape `permanently',
    230 			 * bump score, and elide any full rows.
    231 			 */
    232 			place(curshape, pos, 1);
    233 			score++;
    234 			elide();
    235 
    236 			/*
    237 			 * Choose a new shape.  If it does not fit,
    238 			 * the game is over.
    239 			 */
    240 			curshape = nextshape;
    241 			nextshape = randshape();
    242 			pos = A_FIRST*B_COLS + (B_COLS/2)-1;
    243 			if (!fits_in(curshape, pos))
    244 				break;
    245 			continue;
    246 		}
    247 
    248 		/*
    249 		 * Handle command keys.
    250 		 */
    251 		if (c == keys[5]) {
    252 			/* quit */
    253 			break;
    254 		}
    255 		if (c == keys[4]) {
    256 			static char msg[] =
    257 			    "paused - press RETURN to continue";
    258 
    259 			place(curshape, pos, 1);
    260 			do {
    261 				scr_update();
    262 				scr_msg(key_msg, 0);
    263 				scr_msg(msg, 1);
    264 				(void) fflush(stdout);
    265 			} while (rwait((struct timeval *)NULL) == -1);
    266 			scr_msg(msg, 0);
    267 			scr_msg(key_msg, 1);
    268 			place(curshape, pos, 0);
    269 			continue;
    270 		}
    271 		if (c == keys[0]) {
    272 			/* move left */
    273 			if (fits_in(curshape, pos - 1))
    274 				pos--;
    275 			continue;
    276 		}
    277 		if (c == keys[1]) {
    278 			/* turn */
    279 			const struct shape *new = &shapes[curshape->rot];
    280 
    281 			if (fits_in(new, pos))
    282 				curshape = new;
    283 			continue;
    284 		}
    285 		if (c == keys[2]) {
    286 			/* move right */
    287 			if (fits_in(curshape, pos + 1))
    288 				pos++;
    289 			continue;
    290 		}
    291 		if (c == keys[3]) {
    292 			/* move to bottom */
    293 			while (fits_in(curshape, pos + B_COLS)) {
    294 				pos += B_COLS;
    295 				score++;
    296 			}
    297 			continue;
    298 		}
    299 		if (c == '\f') {
    300 			scr_clear();
    301 			scr_msg(key_msg, 1);
    302 		}
    303 	}
    304 
    305 	scr_clear();
    306 	scr_end();
    307 
    308 	(void)printf("Your score:  %d point%s  x  level %d  =  %d\n",
    309 	    score, score == 1 ? "" : "s", level, score * level);
    310 	savescore(level);
    311 
    312 	printf("\nHit RETURN to see high scores, ^C to skip.\n");
    313 
    314 	while ((i = getchar()) != '\n')
    315 		if (i == EOF)
    316 			break;
    317 
    318 	showscores(level);
    319 
    320 	exit(0);
    321 }
    322 
    323 void
    324 onintr(signo)
    325 	int signo __attribute__((__unused__));
    326 {
    327 	scr_clear();
    328 	scr_end();
    329 	exit(0);
    330 }
    331 
    332 void
    333 usage()
    334 {
    335 	(void)fprintf(stderr, "usage: tetris [-ps] [-k keys] [-l level]\n");
    336 	exit(1);
    337 }
    338