xref: /netbsd-src/games/tetris/tetris.c (revision afab4e300d3a9fb07dd8c80daf53d0feb3345706)
1 /*	$NetBSD: tetris.c,v 1.33 2020/07/21 02:42:05 nia 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\
40  The Regents of the University of California.  All rights reserved.");
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 int	Offset;			/* used to center board & shapes */
66 
67 static const struct shape *curshape;
68 const struct shape *nextshape;
69 
70 long	fallrate;		/* less than 1 million; smaller => faster */
71 
72 int	score;			/* the obvious thing */
73 gid_t	gid, egid;
74 
75 char	key_msg[100];
76 int	showpreview;
77 int	nocolor;
78 
79 static void elide(void);
80 static void setup_board(void);
81 static void onintr(int) __dead;
82 static void usage(void) __dead;
83 
84 /*
85  * Set up the initial board.  The bottom display row is completely set,
86  * along with another (hidden) row underneath that.  Also, the left and
87  * right edges are set.
88  */
89 static void
90 setup_board(void)
91 {
92 	int i;
93 	cell *p;
94 
95 	p = board;
96 	for (i = B_SIZE; i; i--)
97 		*p++ = (i <= (2 * B_COLS) || (i % B_COLS) < 2) ? 7 : 0;
98 }
99 
100 /*
101  * Elide any full active rows.
102  */
103 static void
104 elide(void)
105 {
106 	int i, j, base;
107 	cell *p;
108 
109 	for (i = A_FIRST; i < A_LAST; i++) {
110 		base = i * B_COLS + 1;
111 		p = &board[base];
112 		for (j = B_COLS - 2; *p++ != 0;) {
113 			if (--j <= 0) {
114 				/* this row is to be elided */
115 				memset(&board[base], 0, B_COLS - 2);
116 				scr_update();
117 				tsleep();
118 				while (--base != 0)
119 					board[base + B_COLS] = board[base];
120 				/* don't forget to clear 0th row */
121 				memset(&board[1], 0, B_COLS - 2);
122 				scr_update();
123 				tsleep();
124 				break;
125 			}
126 		}
127 	}
128 }
129 
130 int
131 main(int argc, char *argv[])
132 {
133 	int pos, c;
134 	const char *keys;
135 	int level = 2;
136 #define NUMKEYS 7
137 	char key_write[NUMKEYS][10];
138 	int ch, i, j;
139 	int fd;
140 
141 	gid = getgid();
142 	egid = getegid();
143 	setegid(gid);
144 
145 	fd = open("/dev/null", O_RDONLY);
146 	if (fd < 3)
147 		exit(1);
148 	close(fd);
149 
150 	keys = "jkl pqn";
151 
152 	while ((ch = getopt(argc, argv, "bk:l:ps")) != -1)
153 		switch(ch) {
154 		case 'b':
155 			nocolor = 1;
156 			break;
157 		case 'k':
158 			if (strlen(keys = optarg) != NUMKEYS)
159 				usage();
160 			break;
161 		case 'l':
162 			level = atoi(optarg);
163 			if (level < MINLEVEL || level > MAXLEVEL) {
164 				errx(1, "level must be from %d to %d",
165 				     MINLEVEL, MAXLEVEL);
166 			}
167 			break;
168 		case 'p':
169 			showpreview = 1;
170 			break;
171 		case 's':
172 			showscores(0);
173 			exit(0);
174 		case '?':
175 		default:
176 			usage();
177 		}
178 
179 	argc -= optind;
180 	argv += optind;
181 
182 	if (argc)
183 		usage();
184 
185 	fallrate = 1000000 / level;
186 
187 	for (i = 0; i <= (NUMKEYS-1); i++) {
188 		for (j = i+1; j <= (NUMKEYS-1); j++) {
189 			if (keys[i] == keys[j]) {
190 				errx(1, "duplicate command keys specified.");
191 			}
192 		}
193 		if (keys[i] == ' ')
194 			strcpy(key_write[i], "<space>");
195 		else {
196 			key_write[i][0] = keys[i];
197 			key_write[i][1] = '\0';
198 		}
199 	}
200 
201 	snprintf(key_msg, sizeof(key_msg),
202 "%s - left  %s - rotate  %s - right  %s - drop  %s - pause  %s - quit  %s - down",
203 		key_write[0], key_write[1], key_write[2], key_write[3],
204 		key_write[4], key_write[5], key_write[6]);
205 
206 	(void)signal(SIGINT, onintr);
207 	scr_init();
208 	setup_board();
209 
210 	scr_set();
211 
212 	pos = A_FIRST*B_COLS + (B_COLS/2)-1;
213 	nextshape = randshape();
214 	curshape = randshape();
215 
216 	scr_msg(key_msg, 1);
217 
218 	for (;;) {
219 		place(curshape, pos, 1);
220 		scr_update();
221 		place(curshape, pos, 0);
222 		c = tgetchar();
223 		if (c < 0) {
224 			/*
225 			 * Timeout.  Move down if possible.
226 			 */
227 			if (fits_in(curshape, pos + B_COLS)) {
228 				pos += B_COLS;
229 				continue;
230 			}
231 
232 			/*
233 			 * Put up the current shape `permanently',
234 			 * bump score, and elide any full rows.
235 			 */
236 			place(curshape, pos, 1);
237 			score++;
238 			elide();
239 
240 			/*
241 			 * Choose a new shape.  If it does not fit,
242 			 * the game is over.
243 			 */
244 			curshape = nextshape;
245 			nextshape = randshape();
246 			pos = A_FIRST*B_COLS + (B_COLS/2)-1;
247 			if (!fits_in(curshape, pos))
248 				break;
249 			continue;
250 		}
251 
252 		/*
253 		 * Handle command keys.
254 		 */
255 		if (c == keys[5]) {
256 			/* quit */
257 			break;
258 		}
259 		if (c == keys[4]) {
260 			static char msg[] =
261 			    "paused - press RETURN to continue";
262 
263 			place(curshape, pos, 1);
264 			do {
265 				scr_update();
266 				scr_msg(key_msg, 0);
267 				scr_msg(msg, 1);
268 				(void) fflush(stdout);
269 			} while (rwait(NULL) == -1);
270 			scr_msg(msg, 0);
271 			scr_msg(key_msg, 1);
272 			place(curshape, pos, 0);
273 			continue;
274 		}
275 		if (c == keys[0]) {
276 			/* move left */
277 			if (fits_in(curshape, pos - 1))
278 				pos--;
279 			continue;
280 		}
281 		if (c == keys[1]) {
282 			/* turn */
283 			const struct shape *new = &shapes[curshape->rot];
284 
285 			if (fits_in(new, pos))
286 				curshape = new;
287 			continue;
288 		}
289 		if (c == keys[2]) {
290 			/* move right */
291 			if (fits_in(curshape, pos + 1))
292 				pos++;
293 			continue;
294 		}
295 		if (c == keys[3]) {
296 			/* move to bottom */
297 			while (fits_in(curshape, pos + B_COLS)) {
298 				pos += B_COLS;
299 				score++;
300 			}
301 			continue;
302 		}
303 		if (c == keys[6]) {
304 			/* move down */
305 			if (fits_in(curshape, pos + B_COLS)) {
306 				pos += B_COLS;
307 				score++;
308 			}
309 			continue;
310 		}
311 		if (c == '\f') {
312 			scr_clear();
313 			scr_msg(key_msg, 1);
314 		}
315 	}
316 
317 	scr_clear();
318 	scr_end();
319 
320 	(void)printf("Your score:  %d point%s  x  level %d  =  %d\n",
321 	    score, score == 1 ? "" : "s", level, score * level);
322 	savescore(level);
323 
324 	printf("\nHit RETURN to see high scores, ^C to skip.\n");
325 
326 	while ((i = getchar()) != '\n')
327 		if (i == EOF)
328 			break;
329 
330 	showscores(level);
331 
332 	exit(0);
333 }
334 
335 static void
336 onintr(int signo __unused)
337 {
338 	scr_clear();
339 	scr_end();
340 	exit(0);
341 }
342 
343 static void
344 usage(void)
345 {
346 	(void)fprintf(stderr, "usage: %s [-bps] [-k keys] [-l level]\n",
347 	    getprogname());
348 	exit(1);
349 }
350