xref: /netbsd-src/games/tetris/screen.c (revision 9573673d78c64ea1eac42d7f2e9521be89932ae5)
1 /*	$NetBSD: screen.c,v 1.31 2015/11/06 19:53:37 christos 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 = tiparm(cursor_address, r, c);
93 	if (buf != NULL)
94 		putpad(buf);
95 }
96 
97 static void
98 setcolor(int c)
99 {
100 	char *buf;
101 	char monochrome[] = "\033[0m";
102 	if (nocolor == 1)
103 		return;
104 	if (set_a_foreground == NULL)
105 		return;
106 
107 	if (c == 0 || c == 7)
108 		buf = monochrome;
109 	else
110 		buf = tiparm(set_a_foreground, c);
111 	if (buf != NULL)
112 		putpad(buf);
113 }
114 
115 /*
116  * Set up from termcap.
117  */
118 void
119 scr_init(void)
120 {
121 
122 	setupterm(NULL, 0, NULL);
123 	if (clear_screen == NULL)
124 		stop("cannot clear screen");
125 	if (cursor_address == NULL || cursor_up == NULL)
126 		stop("cannot do random cursor positioning");
127 }
128 
129 /* this foolery is needed to modify tty state `atomically' */
130 static jmp_buf scr_onstop;
131 
132 static void
133 stopset(int sig)
134 {
135 	sigset_t set;
136 
137 	(void) signal(sig, SIG_DFL);
138 	(void) kill(getpid(), sig);
139 	sigemptyset(&set);
140 	sigaddset(&set, sig);
141 	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
142 	longjmp(scr_onstop, 1);
143 }
144 
145 static void
146 scr_stop(int sig)
147 {
148 	sigset_t set;
149 
150 	scr_end();
151 	(void) kill(getpid(), sig);
152 	sigemptyset(&set);
153 	sigaddset(&set, sig);
154 	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
155 	scr_set();
156 	scr_msg(key_msg, 1);
157 }
158 
159 /*
160  * Set up screen mode.
161  */
162 void
163 scr_set(void)
164 {
165 	struct winsize ws;
166 	struct termios newtt;
167 	sigset_t nsigset, osigset;
168 	void (*ttou)(int);
169 
170 	sigemptyset(&nsigset);
171 	sigaddset(&nsigset, SIGTSTP);
172 	sigaddset(&nsigset, SIGTTOU);
173 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
174 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
175 		(void) signal(SIGTSTP, SIG_IGN);
176 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
177 		(void) signal(SIGTTOU, SIG_IGN);
178 	/*
179 	 * At last, we are ready to modify the tty state.  If
180 	 * we stop while at it, stopset() above will longjmp back
181 	 * to the setjmp here and we will start over.
182 	 */
183 	(void) setjmp(scr_onstop);
184 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
185 	Rows = 0, Cols = 0;
186 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
187 		Rows = ws.ws_row;
188 		Cols = ws.ws_col;
189 	}
190 	if (Rows == 0)
191 		Rows = lines;
192 	if (Cols == 0)
193 	    Cols = columns;
194 	if (Rows < MINROWS || Cols < MINCOLS) {
195 		(void) fprintf(stderr,
196 		    "the screen is too small: must be at least %dx%d, ",
197 		    MINCOLS, MINROWS);
198 		stop("");	/* stop() supplies \n */
199 	}
200 	if (tcgetattr(0, &oldtt) < 0)
201 		stop("tcgetattr() fails");
202 	newtt = oldtt;
203 	newtt.c_lflag &= ~(ICANON|ECHO);
204 	newtt.c_oflag &= ~OXTABS;
205 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
206 		stop("tcsetattr() fails");
207 	ospeed = cfgetospeed(&newtt);
208 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
209 
210 	/*
211 	 * We made it.  We are now in screen mode, modulo TIstr
212 	 * (which we will fix immediately).
213 	 */
214 	if (enter_ca_mode)
215 		putstr(enter_ca_mode);
216 	if (cursor_invisible)
217 		putstr(cursor_invisible);
218 	if (tstp != SIG_IGN)
219 		(void) signal(SIGTSTP, scr_stop);
220 	if (ttou != SIG_IGN)
221 		(void) signal(SIGTTOU, ttou);
222 
223 	isset = 1;
224 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
225 	scr_clear();
226 }
227 
228 /*
229  * End screen mode.
230  */
231 void
232 scr_end(void)
233 {
234 	sigset_t nsigset, osigset;
235 
236 	sigemptyset(&nsigset);
237 	sigaddset(&nsigset, SIGTSTP);
238 	sigaddset(&nsigset, SIGTTOU);
239 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
240 	/* move cursor to last line */
241 	if (cursor_to_ll)
242 		putstr(cursor_to_ll);
243 	else
244 		moveto(Rows - 1, 0);
245 	/* exit screen mode */
246 	if (exit_ca_mode)
247 		putstr(exit_ca_mode);
248 	if (cursor_normal)
249 		putstr(cursor_normal);
250 	(void) fflush(stdout);
251 	(void) tcsetattr(0, TCSADRAIN, &oldtt);
252 	isset = 0;
253 	/* restore signals */
254 	(void) signal(SIGTSTP, tstp);
255 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
256 }
257 
258 void
259 stop(const char *why)
260 {
261 
262 	if (isset)
263 		scr_end();
264 	(void) fprintf(stderr, "aborting: %s\n", why);
265 	exit(1);
266 }
267 
268 /*
269  * Clear the screen, forgetting the current contents in the process.
270  */
271 void
272 scr_clear(void)
273 {
274 
275 	putpad(clear_screen);
276 	curscore = -1;
277 	memset((char *)curscreen, 0, sizeof(curscreen));
278 }
279 
280 #if vax && !__GNUC__
281 typedef int regcell;	/* pcc is bad at `register char', etc */
282 #else
283 typedef cell regcell;
284 #endif
285 
286 /*
287  * Update the screen.
288  */
289 void
290 scr_update(void)
291 {
292 	cell *bp, *sp;
293 	regcell so, cur_so = 0;
294 	int i, ccol, j;
295 	sigset_t nsigset, osigset;
296 	static const struct shape *lastshape;
297 
298 	sigemptyset(&nsigset);
299 	sigaddset(&nsigset, SIGTSTP);
300 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
301 
302 	/* always leave cursor after last displayed point */
303 	curscreen[D_LAST * B_COLS - 1] = -1;
304 
305 	if (score != curscore) {
306 		if (cursor_home)
307 			putpad(cursor_home);
308 		else
309 			moveto(0, 0);
310 		setcolor(0);
311 		(void) printf("Score: %d", score);
312 		curscore = score;
313 	}
314 
315 	/* draw preview of nextpattern */
316 	if (showpreview && (nextshape != lastshape)) {
317 		static int r=5, c=2;
318 		int tr, tc, t;
319 
320 		lastshape = nextshape;
321 
322 		/* clean */
323 		putpad(exit_standout_mode);
324 		moveto(r-1, c-1); putstr("          ");
325 		moveto(r,   c-1); putstr("          ");
326 		moveto(r+1, c-1); putstr("          ");
327 		moveto(r+2, c-1); putstr("          ");
328 
329 		moveto(r-3, c-2);
330 		putstr("Next shape:");
331 
332 		/* draw */
333 		setcolor(nextshape->color);
334 		putpad(enter_standout_mode);
335 		moveto(r, 2*c);
336 		putstr("  ");
337 		for(i=0; i<3; i++) {
338 			t = c + r*B_COLS;
339 			t += nextshape->off[i];
340 
341 			tr = t / B_COLS;
342 			tc = t % B_COLS;
343 
344 			moveto(tr, 2*tc);
345 			putstr("  ");
346 		}
347 		putpad(exit_standout_mode);
348 	}
349 
350 	bp = &board[D_FIRST * B_COLS];
351 	sp = &curscreen[D_FIRST * B_COLS];
352 	for (j = D_FIRST; j < D_LAST; j++) {
353 		ccol = -1;
354 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
355 			if (*sp == (so = *bp))
356 				continue;
357 			*sp = so;
358 			if (i != ccol) {
359 				if (cur_so && move_standout_mode) {
360 					putpad(exit_standout_mode);
361 					cur_so = 0;
362 				}
363 				moveto(RTOD(j), CTOD(i));
364 			}
365 			if (enter_standout_mode) {
366 				if (so != cur_so) {
367 					setcolor(so);
368 					putpad(so ?
369 					    enter_standout_mode :
370 					    exit_standout_mode);
371 					cur_so = so;
372 				}
373 #ifdef DEBUG
374 				char buf[3];
375 				snprintf(buf, sizeof(buf), "%d%d", so, so);
376 				putstr(buf);
377 #else
378 				putstr("  ");
379 #endif
380 			} else
381 				putstr(so ? "XX" : "  ");
382 			ccol = i + 1;
383 			/*
384 			 * Look ahead a bit, to avoid extra motion if
385 			 * we will be redrawing the cell after the next.
386 			 * Motion probably takes four or more characters,
387 			 * so we save even if we rewrite two cells
388 			 * `unnecessarily'.  Skip it all, though, if
389 			 * the next cell is a different color.
390 			 */
391 #define	STOP (B_COLS - 3)
392 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
393 				continue;
394 			if (sp[2] != bp[2])
395 				sp[1] = -1;
396 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
397 				sp[2] = -1;
398 				sp[1] = -1;
399 			}
400 		}
401 	}
402 	if (cur_so)
403 		putpad(exit_standout_mode);
404 	(void) fflush(stdout);
405 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
406 }
407 
408 /*
409  * Write a message (set!=0), or clear the same message (set==0).
410  * (We need its length in case we have to overwrite with blanks.)
411  */
412 void
413 scr_msg(char *s, int set)
414 {
415 
416 	if (set || clr_eol == NULL) {
417 		int l = strlen(s);
418 
419 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
420 		if (set)
421 			putstr(s);
422 		else
423 			while (--l >= 0)
424 				(void) putchar(' ');
425 	} else {
426 		moveto(Rows - 2, 0);
427 		putpad(clr_eol);
428 	}
429 }
430