xref: /netbsd-src/games/worm/worm.c (revision f14316bcbc544b96a93e884bc5c2b15fd60e22ae)
1 /*	$NetBSD: worm.c,v 1.30 2011/05/23 23:03:38 joerg Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1993\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)worm.c	8.1 (Berkeley) 5/31/93";
41 #else
42 __RCSID("$NetBSD: worm.c,v 1.30 2011/05/23 23:03:38 joerg Exp $");
43 #endif
44 #endif /* not lint */
45 
46 /*
47  * Worm.  Written by Michael Toy
48  * UCSC
49  */
50 
51 #include <ctype.h>
52 #include <curses.h>
53 #include <err.h>
54 #include <signal.h>
55 #include <stdlib.h>
56 #include <termios.h>
57 #include <unistd.h>
58 
59 #define newlink() (struct body *) malloc(sizeof (struct body));
60 #define HEAD '@'
61 #define BODY 'o'
62 #define LENGTH 7
63 #define RUNLEN 8
64 #define CNTRL(p) (p-'A'+1)
65 
66 struct body {
67 	int x;
68 	int y;
69 	struct body *prev;
70 	struct body *next;
71 };
72 
73 static WINDOW *tv;
74 static WINDOW *stw;
75 static struct body *head, *tail, goody;
76 static int growing = 0;
77 static int running = 0;
78 static int slow = 0;
79 static int score = 0;
80 static int start_len = LENGTH;
81 static int visible_len;
82 static int lastch;
83 static char outbuf[BUFSIZ];
84 
85 int	main(int, char **);
86 static void crash(void) __dead;
87 static void display(const struct body *, char);
88 static void leave(int) __dead;
89 static void life(void);
90 static void newpos(struct body *);
91 static void process(int);
92 static void prize(void);
93 static int rnd(int);
94 static void setup(void);
95 static void wake(int);
96 
97 int
98 main(int argc, char **argv)
99 {
100 
101 	/* Revoke setgid privileges */
102 	setgid(getgid());
103 
104 	setbuf(stdout, outbuf);
105 	srand(getpid());
106 	signal(SIGALRM, wake);
107 	signal(SIGINT, leave);
108 	signal(SIGQUIT, leave);
109 	if (!initscr())
110 		errx(0, "couldn't initialize screen");
111 	cbreak();
112 	noecho();
113 #ifdef KEY_LEFT
114 	keypad(stdscr, TRUE);
115 #endif
116 	slow = (baudrate() <= 1200);
117 	clear();
118 	if (COLS < 18 || LINES < 5) {
119 		/*
120 		 * Insufficient room for the line with " Worm" and the
121 		 * score if fewer than 18 columns; insufficient room for
122 		 * anything much if fewer than 5 lines.
123 		 */
124 		endwin();
125 		errx(1, "screen too small");
126 	}
127 	if (argc == 2)
128 		start_len = atoi(argv[1]);
129 	if ((start_len <= 0) || (start_len > ((LINES-3) * (COLS-2)) / 3))
130 		start_len = LENGTH;
131 	stw = newwin(1, COLS-1, 0, 0);
132 	tv = newwin(LINES-1, COLS-1, 1, 0);
133 	box(tv, '*', '*');
134 	scrollok(tv, FALSE);
135 	scrollok(stw, FALSE);
136 	wmove(stw, 0, 0);
137 	wprintw(stw, " Worm");
138 	refresh();
139 	wrefresh(stw);
140 	wrefresh(tv);
141 	life();			/* Create the worm */
142 	prize();		/* Put up a goal */
143 	while(1)
144 	{
145 		if (running)
146 		{
147 			running--;
148 			process(lastch);
149 		}
150 		else
151 		{
152 		    fflush(stdout);
153 		    process(getch());
154 		}
155 	}
156 }
157 
158 static void
159 life(void)
160 {
161 	struct body *bp, *np;
162 	int i, j = 1;
163 
164 	np = NULL;
165 	head = newlink();
166 	if (head == NULL)
167 		err(1, NULL);
168 	head->x = start_len % (COLS-5) + 2;
169 	head->y = LINES / 2;
170 	head->next = NULL;
171 	display(head, HEAD);
172 	for (i = 0, bp = head; i < start_len; i++, bp = np) {
173 		np = newlink();
174 		if (np == NULL)
175 			err(1, NULL);
176 		np->next = bp;
177 		bp->prev = np;
178 		if (((bp->x <= 2) && (j == 1)) || ((bp->x >= COLS-4) && (j == -1))) {
179 			j *= -1;
180 			np->x = bp->x;
181 			np->y = bp->y + 1;
182 		} else {
183 			np->x = bp->x - j;
184 			np->y = bp->y;
185 		}
186 		display(np, BODY);
187 	}
188 	tail = np;
189 	tail->prev = NULL;
190 	visible_len = start_len + 1;
191 }
192 
193 static void
194 display(const struct body *pos, char chr)
195 {
196 	wmove(tv, pos->y, pos->x);
197 	waddch(tv, chr);
198 }
199 
200 static void
201 leave(int dummy)
202 {
203 	endwin();
204 
205 	if (dummy == 0){	/* called via crash() */
206 		printf("\nWell, you ran into something and the game is over.\n");
207 		printf("Your final score was %d\n\n", score);
208 	}
209 	exit(0);
210 }
211 
212 static void
213 wake(int dummy)
214 {
215 	signal(SIGALRM, wake);
216 	fflush(stdout);
217 	process(lastch);
218 }
219 
220 static int
221 rnd(int range)
222 {
223 	return abs((rand()>>5)+(rand()>>5)) % range;
224 }
225 
226 static void
227 newpos(struct body *bp)
228 {
229 	if (visible_len == (LINES-3) * (COLS-3) - 1) {
230 		endwin();
231 
232 		printf("\nYou won!\n");
233 		printf("Your final score was %d\n\n", score);
234 		exit(0);
235 	}
236 	do {
237 		bp->y = rnd(LINES-3)+ 1;
238 		bp->x = rnd(COLS-3) + 1;
239 		wmove(tv, bp->y, bp->x);
240 	} while(winch(tv) != ' ');
241 }
242 
243 static void
244 prize(void)
245 {
246 	int value;
247 
248 	value = rnd(9) + 1;
249 	newpos(&goody);
250 	waddch(tv, value+'0');
251 	wrefresh(tv);
252 }
253 
254 static void
255 process(int ch)
256 {
257 	int x,y;
258 	struct body *nh;
259 
260 	alarm(0);
261 	x = head->x;
262 	y = head->y;
263 	switch(ch)
264 	{
265 #ifdef KEY_LEFT
266 		case KEY_LEFT:
267 #endif
268 		case 'h':
269 			x--; break;
270 
271 #ifdef KEY_DOWN
272 		case KEY_DOWN:
273 #endif
274 		case 'j':
275 			y++; break;
276 
277 #ifdef KEY_UP
278 		case KEY_UP:
279 #endif
280 		case 'k':
281 			y--; break;
282 
283 #ifdef KEY_RIGHT
284 		case KEY_RIGHT:
285 #endif
286 		case 'l':
287 			x++; break;
288 
289 		case 'H': x--; running = RUNLEN; ch = tolower(ch); break;
290 		case 'J': y++; running = RUNLEN/2; ch = tolower(ch); break;
291 		case 'K': y--; running = RUNLEN/2; ch = tolower(ch); break;
292 		case 'L': x++; running = RUNLEN; ch = tolower(ch); break;
293 		case '\f': setup(); return;
294 
295 		case ERR:
296 		case CNTRL('C'):
297 		case CNTRL('D'):
298 			crash();
299 			return;
300 
301 		default: if (! running) alarm(1);
302 			   return;
303 	}
304 	lastch = ch;
305 	if (growing == 0)
306 	{
307 		display(tail, ' ');
308 		tail->next->prev = NULL;
309 		nh = tail->next;
310 		free(tail);
311 		tail = nh;
312 		visible_len--;
313 	}
314 	else growing--;
315 	display(head, BODY);
316 	wmove(tv, y, x);
317 	if (isdigit(ch = winch(tv)))
318 	{
319 		growing += ch-'0';
320 		prize();
321 		score += growing;
322 		running = 0;
323 		wmove(stw, 0, COLS - 12);
324 		wprintw(stw, "Score: %3d", score);
325 		wrefresh(stw);
326 	}
327 	else if(ch != ' ') crash();
328 	nh = newlink();
329 	if (nh == NULL)
330 		err(1, NULL);
331 	nh->next = NULL;
332 	nh->prev = head;
333 	head->next = nh;
334 	nh->y = y;
335 	nh->x = x;
336 	display(nh, HEAD);
337 	head = nh;
338 	visible_len++;
339 	if (!(slow && running))
340 	{
341 		wmove(tv, head->y, head->x);
342 		wrefresh(tv);
343 	}
344 	if (!running)
345 		alarm(1);
346 }
347 
348 static void
349 crash(void)
350 {
351 	leave(0);
352 }
353 
354 static void
355 setup(void)
356 {
357 	clear();
358 	refresh();
359 	touchwin(stw);
360 	wrefresh(stw);
361 	touchwin(tv);
362 	wrefresh(tv);
363 	alarm(1);
364 }
365