xref: /netbsd/games/tetris/screen.c (revision 6550d01e)
1 /*	$NetBSD: screen.c,v 1.26 2010/02/03 15:34:39 roy 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  *	@(#)screen.c	8.1 (Berkeley) 5/31/93
35  */
36 
37 /*
38  * Tetris screen control.
39  */
40 
41 #include <sys/cdefs.h>
42 #include <sys/ioctl.h>
43 
44 #include <setjmp.h>
45 #include <signal.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <term.h>
50 #include <termios.h>
51 #include <unistd.h>
52 
53 #ifndef sigmask
54 #define sigmask(s) (1 << ((s) - 1))
55 #endif
56 
57 #include "screen.h"
58 #include "tetris.h"
59 
60 static cell curscreen[B_SIZE];	/* 1 => standout (or otherwise marked) */
61 static int curscore;
62 static int isset;		/* true => terminal is in game mode */
63 static struct termios oldtt;
64 static void (*tstp)(int);
65 
66 static	void	scr_stop(int);
67 static	void	stopset(int) __dead;
68 
69 
70 /*
71  * Routine used by tputs().
72  */
73 int
74 put(int c)
75 {
76 
77 	return (putchar(c));
78 }
79 
80 /*
81  * putstr() is for unpadded strings (either as in termcap(5) or
82  * simply literal strings); putpad() is for padded strings with
83  * count=1.  (See screen.h for putpad().)
84  */
85 #define	putstr(s)	(void)fputs(s, stdout)
86 
87 static void
88 moveto(int r, int c)
89 {
90 	char *buf;
91 
92 	buf = vtparm(cursor_address, r, c);
93 	if (buf != NULL)
94 		putpad(buf);
95 }
96 
97 /*
98  * Set up from termcap.
99  */
100 void
101 scr_init(void)
102 {
103 
104 	setupterm(NULL, 0, NULL);
105 	if (clear_screen == NULL)
106 		stop("cannot clear screen");
107 	if (cursor_address == NULL || cursor_up == NULL)
108 		stop("cannot do random cursor positioning");
109 }
110 
111 /* this foolery is needed to modify tty state `atomically' */
112 static jmp_buf scr_onstop;
113 
114 static void
115 stopset(int sig)
116 {
117 	sigset_t set;
118 
119 	(void) signal(sig, SIG_DFL);
120 	(void) kill(getpid(), sig);
121 	sigemptyset(&set);
122 	sigaddset(&set, sig);
123 	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
124 	longjmp(scr_onstop, 1);
125 }
126 
127 static void
128 scr_stop(int sig)
129 {
130 	sigset_t set;
131 
132 	scr_end();
133 	(void) kill(getpid(), sig);
134 	sigemptyset(&set);
135 	sigaddset(&set, sig);
136 	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
137 	scr_set();
138 	scr_msg(key_msg, 1);
139 }
140 
141 /*
142  * Set up screen mode.
143  */
144 void
145 scr_set(void)
146 {
147 	struct winsize ws;
148 	struct termios newtt;
149 	sigset_t nsigset, osigset;
150 	void (*ttou)(int);
151 
152 	sigemptyset(&nsigset);
153 	sigaddset(&nsigset, SIGTSTP);
154 	sigaddset(&nsigset, SIGTTOU);
155 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
156 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
157 		(void) signal(SIGTSTP, SIG_IGN);
158 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
159 		(void) signal(SIGTTOU, SIG_IGN);
160 	/*
161 	 * At last, we are ready to modify the tty state.  If
162 	 * we stop while at it, stopset() above will longjmp back
163 	 * to the setjmp here and we will start over.
164 	 */
165 	(void) setjmp(scr_onstop);
166 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
167 	Rows = 0, Cols = 0;
168 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
169 		Rows = ws.ws_row;
170 		Cols = ws.ws_col;
171 	}
172 	if (Rows == 0)
173 		Rows = lines;
174 	if (Cols == 0)
175 	    Cols = columns;
176 	if (Rows < MINROWS || Cols < MINCOLS) {
177 		(void) fprintf(stderr,
178 		    "the screen is too small: must be at least %dx%d, ",
179 		    MINCOLS, MINROWS);
180 		stop("");	/* stop() supplies \n */
181 	}
182 	if (tcgetattr(0, &oldtt) < 0)
183 		stop("tcgetattr() fails");
184 	newtt = oldtt;
185 	newtt.c_lflag &= ~(ICANON|ECHO);
186 	newtt.c_oflag &= ~OXTABS;
187 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
188 		stop("tcsetattr() fails");
189 	ospeed = cfgetospeed(&newtt);
190 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
191 
192 	/*
193 	 * We made it.  We are now in screen mode, modulo TIstr
194 	 * (which we will fix immediately).
195 	 */
196 	if (enter_ca_mode)
197 		putstr(enter_ca_mode);
198 	if (cursor_invisible)
199 		putstr(cursor_invisible);
200 	if (tstp != SIG_IGN)
201 		(void) signal(SIGTSTP, scr_stop);
202 	if (ttou != SIG_IGN)
203 		(void) signal(SIGTTOU, ttou);
204 
205 	isset = 1;
206 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
207 	scr_clear();
208 }
209 
210 /*
211  * End screen mode.
212  */
213 void
214 scr_end(void)
215 {
216 	sigset_t nsigset, osigset;
217 
218 	sigemptyset(&nsigset);
219 	sigaddset(&nsigset, SIGTSTP);
220 	sigaddset(&nsigset, SIGTTOU);
221 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
222 	/* move cursor to last line */
223 	if (cursor_to_ll)
224 		putstr(cursor_to_ll);
225 	else
226 		moveto(Rows - 1, 0);
227 	/* exit screen mode */
228 	if (exit_ca_mode)
229 		putstr(exit_ca_mode);
230 	if (cursor_normal)
231 		putstr(cursor_normal);
232 	(void) fflush(stdout);
233 	(void) tcsetattr(0, TCSADRAIN, &oldtt);
234 	isset = 0;
235 	/* restore signals */
236 	(void) signal(SIGTSTP, tstp);
237 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
238 }
239 
240 void
241 stop(const char *why)
242 {
243 
244 	if (isset)
245 		scr_end();
246 	(void) fprintf(stderr, "aborting: %s\n", why);
247 	exit(1);
248 }
249 
250 /*
251  * Clear the screen, forgetting the current contents in the process.
252  */
253 void
254 scr_clear(void)
255 {
256 
257 	putpad(clear_screen);
258 	curscore = -1;
259 	memset((char *)curscreen, 0, sizeof(curscreen));
260 }
261 
262 #if vax && !__GNUC__
263 typedef int regcell;	/* pcc is bad at `register char', etc */
264 #else
265 typedef cell regcell;
266 #endif
267 
268 /*
269  * Update the screen.
270  */
271 void
272 scr_update(void)
273 {
274 	cell *bp, *sp;
275 	regcell so, cur_so = 0;
276 	int i, ccol, j;
277 	sigset_t nsigset, osigset;
278 	static const struct shape *lastshape;
279 
280 	sigemptyset(&nsigset);
281 	sigaddset(&nsigset, SIGTSTP);
282 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
283 
284 	/* always leave cursor after last displayed point */
285 	curscreen[D_LAST * B_COLS - 1] = -1;
286 
287 	if (score != curscore) {
288 		if (cursor_home)
289 			putpad(cursor_home);
290 		else
291 			moveto(0, 0);
292 		(void) printf("Score: %d", score);
293 		curscore = score;
294 	}
295 
296 	/* draw preview of nextpattern */
297 	if (showpreview && (nextshape != lastshape)) {
298 		static int r=5, c=2;
299 		int tr, tc, t;
300 
301 		lastshape = nextshape;
302 
303 		/* clean */
304 		putpad(exit_standout_mode);
305 		moveto(r-1, c-1); putstr("          ");
306 		moveto(r,   c-1); putstr("          ");
307 		moveto(r+1, c-1); putstr("          ");
308 		moveto(r+2, c-1); putstr("          ");
309 
310 		moveto(r-3, c-2);
311 		putstr("Next shape:");
312 
313 		/* draw */
314 		putpad(enter_standout_mode);
315 		moveto(r, 2*c);
316 		putstr("  ");
317 		for(i=0; i<3; i++) {
318 			t = c + r*B_COLS;
319 			t += nextshape->off[i];
320 
321 			tr = t / B_COLS;
322 			tc = t % B_COLS;
323 
324 			moveto(tr, 2*tc);
325 			putstr("  ");
326 		}
327 		putpad(exit_standout_mode);
328 	}
329 
330 	bp = &board[D_FIRST * B_COLS];
331 	sp = &curscreen[D_FIRST * B_COLS];
332 	for (j = D_FIRST; j < D_LAST; j++) {
333 		ccol = -1;
334 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
335 			if (*sp == (so = *bp))
336 				continue;
337 			*sp = so;
338 			if (i != ccol) {
339 				if (cur_so && move_standout_mode) {
340 					putpad(exit_standout_mode);
341 					cur_so = 0;
342 				}
343 				moveto(RTOD(j), CTOD(i));
344 			}
345 			if (enter_standout_mode) {
346 				if (so != cur_so) {
347 					putpad(so ?
348 					    enter_standout_mode :
349 					    exit_standout_mode);
350 					cur_so = so;
351 				}
352 				putstr("  ");
353 			} else
354 				putstr(so ? "XX" : "  ");
355 			ccol = i + 1;
356 			/*
357 			 * Look ahead a bit, to avoid extra motion if
358 			 * we will be redrawing the cell after the next.
359 			 * Motion probably takes four or more characters,
360 			 * so we save even if we rewrite two cells
361 			 * `unnecessarily'.  Skip it all, though, if
362 			 * the next cell is a different color.
363 			 */
364 #define	STOP (B_COLS - 3)
365 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
366 				continue;
367 			if (sp[2] != bp[2])
368 				sp[1] = -1;
369 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
370 				sp[2] = -1;
371 				sp[1] = -1;
372 			}
373 		}
374 	}
375 	if (cur_so)
376 		putpad(exit_standout_mode);
377 	(void) fflush(stdout);
378 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
379 }
380 
381 /*
382  * Write a message (set!=0), or clear the same message (set==0).
383  * (We need its length in case we have to overwrite with blanks.)
384  */
385 void
386 scr_msg(char *s, int set)
387 {
388 
389 	if (set || clr_eol == NULL) {
390 		int l = strlen(s);
391 
392 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
393 		if (set)
394 			putstr(s);
395 		else
396 			while (--l >= 0)
397 				(void) putchar(' ');
398 	} else {
399 		moveto(Rows - 2, 0);
400 		putpad(clr_eol);
401 	}
402 }
403