worms.c revision 1.21 
1/*	$OpenBSD: worms.c,v 1.21 2013/08/29 20:22:21 naddy 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/*
33 *
34 *	 @@@	    @@@	   @@@@@@@@@@	  @@@@@@@@@@@	 @@@@@@@@@@@@
35 *	 @@@	    @@@	  @@@@@@@@@@@@	  @@@@@@@@@@@@	 @@@@@@@@@@@@@
36 *	 @@@	    @@@	 @@@@	   @@@@	  @@@@		 @@@@ @@@  @@@@
37 *	 @@@   @@   @@@	 @@@	    @@@	  @@@		 @@@  @@@   @@@
38 *	 @@@  @@@@  @@@	 @@@	    @@@	  @@@		 @@@  @@@   @@@
39 *	 @@@@ @@@@ @@@@	 @@@	    @@@	  @@@		 @@@  @@@   @@@
40 *	  @@@@@@@@@@@@	 @@@@	   @@@@	  @@@		 @@@  @@@   @@@
41 *	   @@@@	 @@@@	  @@@@@@@@@@@@	  @@@		 @@@  @@@   @@@
42 *	    @@	  @@	   @@@@@@@@@@	  @@@		 @@@  @@@   @@@
43 *
44 *				 Eric P. Scott
45 *			  Caltech High Energy Physics
46 *				 October, 1980
47 *
48 */
49#include <sys/types.h>
50
51#include <curses.h>
52#include <err.h>
53#include <signal.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <termios.h>
57#include <unistd.h>
58
59static const struct options {
60	int nopts;
61	int opts[3];
62}
63	normal[8] = {
64	{ 3, { 7, 0, 1 } },
65	{ 3, { 0, 1, 2 } },
66	{ 3, { 1, 2, 3 } },
67	{ 3, { 2, 3, 4 } },
68	{ 3, { 3, 4, 5 } },
69	{ 3, { 4, 5, 6 } },
70	{ 3, { 5, 6, 7 } },
71	{ 3, { 6, 7, 0 } }
72},	upper[8] = {
73	{ 1, { 1, 0, 0 } },
74	{ 2, { 1, 2, 0 } },
75	{ 0, { 0, 0, 0 } },
76	{ 0, { 0, 0, 0 } },
77	{ 0, { 0, 0, 0 } },
78	{ 2, { 4, 5, 0 } },
79	{ 1, { 5, 0, 0 } },
80	{ 2, { 1, 5, 0 } }
81},
82	left[8] = {
83	{ 0, { 0, 0, 0 } },
84	{ 0, { 0, 0, 0 } },
85	{ 0, { 0, 0, 0 } },
86	{ 2, { 2, 3, 0 } },
87	{ 1, { 3, 0, 0 } },
88	{ 2, { 3, 7, 0 } },
89	{ 1, { 7, 0, 0 } },
90	{ 2, { 7, 0, 0 } }
91},
92	right[8] = {
93	{ 1, { 7, 0, 0 } },
94	{ 2, { 3, 7, 0 } },
95	{ 1, { 3, 0, 0 } },
96	{ 2, { 3, 4, 0 } },
97	{ 0, { 0, 0, 0 } },
98	{ 0, { 0, 0, 0 } },
99	{ 0, { 0, 0, 0 } },
100	{ 2, { 6, 7, 0 } }
101},
102	lower[8] = {
103	{ 0, { 0, 0, 0 } },
104	{ 2, { 0, 1, 0 } },
105	{ 1, { 1, 0, 0 } },
106	{ 2, { 1, 5, 0 } },
107	{ 1, { 5, 0, 0 } },
108	{ 2, { 5, 6, 0 } },
109	{ 0, { 0, 0, 0 } },
110	{ 0, { 0, 0, 0 } }
111},
112	upleft[8] = {
113	{ 0, { 0, 0, 0 } },
114	{ 0, { 0, 0, 0 } },
115	{ 0, { 0, 0, 0 } },
116	{ 0, { 0, 0, 0 } },
117	{ 0, { 0, 0, 0 } },
118	{ 1, { 3, 0, 0 } },
119	{ 2, { 1, 3, 0 } },
120	{ 1, { 1, 0, 0 } }
121},
122	upright[8] = {
123	{ 2, { 3, 5, 0 } },
124	{ 1, { 3, 0, 0 } },
125	{ 0, { 0, 0, 0 } },
126	{ 0, { 0, 0, 0 } },
127	{ 0, { 0, 0, 0 } },
128	{ 0, { 0, 0, 0 } },
129	{ 0, { 0, 0, 0 } },
130	{ 1, { 5, 0, 0 } }
131},
132	lowleft[8] = {
133	{ 3, { 7, 0, 1 } },
134	{ 0, { 0, 0, 0 } },
135	{ 0, { 0, 0, 0 } },
136	{ 1, { 1, 0, 0 } },
137	{ 2, { 1, 7, 0 } },
138	{ 1, { 7, 0, 0 } },
139	{ 0, { 0, 0, 0 } },
140	{ 0, { 0, 0, 0 } }
141},
142	lowright[8] = {
143	{ 0, { 0, 0, 0 } },
144	{ 1, { 7, 0, 0 } },
145	{ 2, { 5, 7, 0 } },
146	{ 1, { 5, 0, 0 } },
147	{ 0, { 0, 0, 0 } },
148	{ 0, { 0, 0, 0 } },
149	{ 0, { 0, 0, 0 } },
150	{ 0, { 0, 0, 0 } }
151};
152
153static const char	flavor[] = {
154	'O', '*', '#', '$', '%', '0', '@', '~'
155};
156static const short	xinc[] = {
157	1,  1,  1,  0, -1, -1, -1,  0
158}, yinc[] = {
159	-1,  0,  1,  1,  1,  0, -1, -1
160};
161static struct	worm {
162	int orientation, head;
163	short *xpos, *ypos;
164} *worm;
165
166volatile sig_atomic_t sig_caught = 0;
167
168void	 nomem(void);
169void	 onsig(int);
170
171int
172main(int argc, char *argv[])
173{
174	int x, y, h, n;
175	struct worm *w;
176	const struct options *op;
177	short *ip;
178	int CO, LI, last, bottom, ch, length, number, trail;
179	short **ref;
180	const char *field, *errstr;
181	struct timespec sleeptime;
182	struct termios term;
183	speed_t speed;
184	time_t delay = 0;
185
186	/* set default delay based on terminal baud rate */
187	if (tcgetattr(STDOUT_FILENO, &term) == 0 &&
188	    (speed = cfgetospeed(&term)) > B9600)
189		delay = (speed / B9600) - 1;
190
191	length = 16;
192	number = 3;
193	trail = ' ';
194	field = NULL;
195	while ((ch = getopt(argc, argv, "d:fhl:n:t")) != -1)
196		switch(ch) {
197		case 'd':
198			delay = (time_t)strtonum(optarg, 0, 1000, &errstr);
199			if (errstr)
200			    errx(1, "delay (0-1000) is %s: %s", errstr, optarg);
201			break;
202		case 'f':
203			field = "WORM";
204			break;
205		case 'l':
206			if ((length = atoi(optarg)) < 2 || length > 1024)
207				errx(1, "invalid length (%d - %d).", 2, 1024);
208			break;
209		case 'n':
210			if ((number = atoi(optarg)) < 1 || number > 100)
211				errx(1, "invalid number of worms (%d - %d).",
212				    1, 100);
213			break;
214		case 't':
215			trail = '.';
216			break;
217		case '?': case 'h':
218		default:
219			(void)fprintf(stderr,
220			    "usage: worms [-ft] [-d delay] [-l length] [-n number]\n");
221			exit(1);
222		}
223
224	/* Convert delay from ms -> ns */
225	sleeptime.tv_sec = 0;
226	sleeptime.tv_nsec = delay * 500000;
227	timespecadd(&sleeptime, &sleeptime, &sleeptime);
228
229	if (!(worm = calloc((size_t)number, sizeof(struct worm))))
230		nomem();
231	initscr();
232	curs_set(0);
233	CO = COLS;
234	LI = LINES;
235	last = CO - 1;
236	bottom = LI - 1;
237	if (!(ip = malloc((size_t)(LI * CO * sizeof(short)))) ||
238	    !(ref = calloc((size_t)LI, sizeof(short *)))) {
239		endwin();
240		nomem();
241	}
242	for (n = 0; n < LI; ++n) {
243		ref[n] = ip;
244		ip += CO;
245	}
246	for (ip = ref[0], n = LI * CO; --n >= 0;)
247		*ip++ = 0;
248	for (n = number, w = &worm[0]; --n >= 0; w++) {
249		w->orientation = w->head = 0;
250		if (!(ip = calloc((size_t)length, sizeof(short)))) {
251			endwin();
252			nomem();
253		}
254		w->xpos = ip;
255		for (x = length; --x >= 0;)
256			*ip++ = -1;
257		if (!(ip = calloc((size_t)length, sizeof(short)))) {
258			endwin();
259			nomem();
260		}
261		w->ypos = ip;
262		for (y = length; --y >= 0;)
263			*ip++ = -1;
264	}
265
266	(void)signal(SIGHUP, onsig);
267	(void)signal(SIGINT, onsig);
268	(void)signal(SIGQUIT, onsig);
269	(void)signal(SIGSTOP, onsig);
270	(void)signal(SIGTSTP, onsig);
271	(void)signal(SIGTERM, onsig);
272
273	if (field) {
274		const char *p = field;
275
276		for (y = LI; --y >= 0;) {
277			for (x = CO; --x >= 0;) {
278				addch(*p++);
279				if (!*p)
280					p = field;
281			}
282			refresh();
283		}
284	}
285	for (;;) {
286		refresh();
287		if (sig_caught) {
288			endwin();
289			exit(0);
290		}
291		nanosleep(&sleeptime, NULL);
292		for (n = 0, w = &worm[0]; n < number; n++, w++) {
293			if ((x = w->xpos[h = w->head]) < 0) {
294				mvaddch(y = w->ypos[h] = bottom,
295				    x = w->xpos[h] = 0,
296				    flavor[n % sizeof(flavor)]);
297				ref[y][x]++;
298			}
299			else
300				y = w->ypos[h];
301			if (++h == length)
302				h = 0;
303			if (w->xpos[w->head = h] >= 0) {
304				int x1, y1;
305
306				x1 = w->xpos[h];
307				y1 = w->ypos[h];
308				if (--ref[y1][x1] == 0)
309					mvaddch(y1, x1, trail);
310			}
311			op = &(!x ? (!y ? upleft : (y == bottom ? lowleft : left)) : (x == last ? (!y ? upright : (y == bottom ? lowright : right)) : (!y ? upper : (y == bottom ? lower : normal))))[w->orientation];
312			switch (op->nopts) {
313			case 0:
314				endwin();
315				return(1);
316			case 1:
317				w->orientation = op->opts[0];
318				break;
319			default:
320				w->orientation =
321				    op->opts[arc4random_uniform(op->nopts)];
322			}
323			mvaddch(y += yinc[w->orientation],
324			    x += xinc[w->orientation],
325			    flavor[n % sizeof(flavor)]);
326			ref[w->ypos[h] = y][w->xpos[h] = x]++;
327		}
328	}
329}
330
331void
332onsig(int signo)
333{
334	sig_caught = 1;
335}
336
337void
338nomem(void)
339{
340	errx(1, "not enough memory.");
341}
342