xref: /netbsd-src/games/tetris/screen.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: screen.c,v 1.17 2002/06/02 22:17:38 wiz 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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)screen.c	8.1 (Berkeley) 5/31/93
39  */
40 
41 /*
42  * Tetris screen control.
43  */
44 
45 #include <sys/ioctl.h>
46 
47 #include <setjmp.h>
48 #include <signal.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <termcap.h>
53 #include <termios.h>
54 #include <unistd.h>
55 
56 #ifndef sigmask
57 #define sigmask(s) (1 << ((s) - 1))
58 #endif
59 
60 #include "screen.h"
61 #include "tetris.h"
62 
63 static cell curscreen[B_SIZE];	/* 1 => standout (or otherwise marked) */
64 static int curscore;
65 static int isset;		/* true => terminal is in game mode */
66 static struct termios oldtt;
67 static void (*tstp) __P((int));
68 
69 static	void	scr_stop __P((int));
70 static	void	stopset __P((int)) __attribute__((__noreturn__));
71 
72 
73 /*
74  * Capabilities from TERMCAP.
75  */
76 short	ospeed;
77 
78 static char
79 	*bcstr,			/* backspace char */
80 	*CEstr,			/* clear to end of line */
81 	*CLstr,			/* clear screen */
82 	*CMstr,			/* cursor motion string */
83 #ifdef unneeded
84 	*CRstr,			/* "\r" equivalent */
85 #endif
86 	*HOstr,			/* cursor home */
87 	*LLstr,			/* last line, first column */
88 	*pcstr,			/* pad character */
89 	*TEstr,			/* end cursor motion mode */
90 	*TIstr;			/* begin cursor motion mode */
91 char
92 	*SEstr,			/* end standout mode */
93 	*SOstr;			/* begin standout mode */
94 static int
95 	COnum,			/* co# value */
96 	LInum,			/* li# value */
97 	MSflag;			/* can move in standout mode */
98 
99 
100 struct tcsinfo {	/* termcap string info; some abbrevs above */
101 	char tcname[3];
102 	char **tcaddr;
103 } tcstrings[] = {
104 	{"bc", &bcstr},
105 	{"ce", &CEstr},
106 	{"cl", &CLstr},
107 	{"cm", &CMstr},
108 #ifdef unneeded
109 	{"cr", &CRstr},
110 #endif
111 	{"le", &BC},		/* move cursor left one space */
112 	{"pc", &pcstr},
113 	{"se", &SEstr},
114 	{"so", &SOstr},
115 	{"te", &TEstr},
116 	{"ti", &TIstr},
117 	{"up", &UP},		/* cursor up */
118 	{ {0}, NULL}
119 };
120 
121 /* This is where we will actually stuff the information */
122 
123 static struct tinfo *info;
124 
125 /*
126  * Routine used by tputs().
127  */
128 int
129 put(c)
130 	int c;
131 {
132 
133 	return (putchar(c));
134 }
135 
136 /*
137  * putstr() is for unpadded strings (either as in termcap(5) or
138  * simply literal strings); putpad() is for padded strings with
139  * count=1.  (See screen.h for putpad().)
140  */
141 #define	putstr(s)	(void)fputs(s, stdout)
142 
143 void
144 moveto(int r, int c)
145 {
146 	char buf[256];
147 
148 	if (t_goto(info, CMstr, c, r, buf, 255) == 0)
149 		putpad(buf);
150 }
151 
152 /*
153  * Set up from termcap.
154  */
155 void
156 scr_init()
157 {
158 	static int bsflag, xsflag, sgnum;
159 #ifdef unneeded
160 	static int ncflag;
161 #endif
162 	char *term;
163 	static struct tcninfo {	/* termcap numeric and flag info */
164 		char tcname[3];
165 		int *tcaddr;
166 	} tcflags[] = {
167 		{"bs", &bsflag},
168 		{"ms", &MSflag},
169 #ifdef unneeded
170 		{"nc", &ncflag},
171 #endif
172 		{"xs", &xsflag},
173 		{ {0}, NULL}
174 	}, tcnums[] = {
175 		{"co", &COnum},
176 		{"li", &LInum},
177 		{"sg", &sgnum},
178 		{ {0}, NULL}
179 	};
180 
181 	if ((term = getenv("TERM")) == NULL)
182 		stop("you must set the TERM environment variable");
183 	if (t_getent(&info, term) <= 0)
184 		stop("cannot find your termcap");
185 	{
186 		struct tcsinfo *p;
187 
188 		for (p = tcstrings; p->tcaddr; p++)
189 			*p->tcaddr = t_agetstr(info, p->tcname);
190 	}
191 	{
192 		struct tcninfo *p;
193 
194 		for (p = tcflags; p->tcaddr; p++)
195 			*p->tcaddr = t_getflag(info, p->tcname);
196 		for (p = tcnums; p->tcaddr; p++)
197 			*p->tcaddr = t_getnum(info, p->tcname);
198 	}
199 	if (bsflag)
200 		BC = "\b";
201 	else if (BC == NULL && bcstr != NULL)
202 		BC = bcstr;
203 	if (CLstr == NULL)
204 		stop("cannot clear screen");
205 	if (CMstr == NULL || UP == NULL || BC == NULL)
206 		stop("cannot do random cursor positioning via tgoto()");
207 	PC = pcstr ? *pcstr : 0;
208 	if (sgnum >= 0 || xsflag)
209 		SOstr = SEstr = NULL;
210 #ifdef unneeded
211 	if (ncflag)
212 		CRstr = NULL;
213 	else if (CRstr == NULL)
214 		CRstr = "\r";
215 #endif
216 }
217 
218 /* this foolery is needed to modify tty state `atomically' */
219 static jmp_buf scr_onstop;
220 
221 static void
222 stopset(sig)
223 	int sig;
224 {
225 	sigset_t sigset;
226 
227 	(void) signal(sig, SIG_DFL);
228 	(void) kill(getpid(), sig);
229 	sigemptyset(&sigset);
230 	sigaddset(&sigset, sig);
231 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
232 	longjmp(scr_onstop, 1);
233 }
234 
235 static void
236 scr_stop(sig)
237 	int sig;
238 {
239 	sigset_t sigset;
240 
241 	scr_end();
242 	(void) kill(getpid(), sig);
243 	sigemptyset(&sigset);
244 	sigaddset(&sigset, sig);
245 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
246 	scr_set();
247 	scr_msg(key_msg, 1);
248 }
249 
250 /*
251  * Set up screen mode.
252  */
253 void
254 scr_set()
255 {
256 	struct winsize ws;
257 	struct termios newtt;
258 	sigset_t sigset, osigset;
259 	void (*ttou) __P((int));
260 
261 	sigemptyset(&sigset);
262 	sigaddset(&sigset, SIGTSTP);
263 	sigaddset(&sigset, SIGTTOU);
264 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
265 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
266 		(void) signal(SIGTSTP, SIG_IGN);
267 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
268 		(void) signal(SIGTTOU, SIG_IGN);
269 	/*
270 	 * At last, we are ready to modify the tty state.  If
271 	 * we stop while at it, stopset() above will longjmp back
272 	 * to the setjmp here and we will start over.
273 	 */
274 	(void) setjmp(scr_onstop);
275 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
276 	Rows = 0, Cols = 0;
277 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
278 		Rows = ws.ws_row;
279 		Cols = ws.ws_col;
280 	}
281 	if (Rows == 0)
282 		Rows = LInum;
283 	if (Cols == 0)
284 	Cols = COnum;
285 	if (Rows < MINROWS || Cols < MINCOLS) {
286 		(void) fprintf(stderr,
287 		    "the screen is too small: must be at least %dx%d, ",
288 		    MINCOLS, MINROWS);
289 		stop("");	/* stop() supplies \n */
290 	}
291 	if (tcgetattr(0, &oldtt) < 0)
292 		stop("tcgetattr() fails");
293 	newtt = oldtt;
294 	newtt.c_lflag &= ~(ICANON|ECHO);
295 	newtt.c_oflag &= ~OXTABS;
296 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
297 		stop("tcsetattr() fails");
298 	ospeed = cfgetospeed(&newtt);
299 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
300 
301 	/*
302 	 * We made it.  We are now in screen mode, modulo TIstr
303 	 * (which we will fix immediately).
304 	 */
305 	if (TIstr)
306 		putstr(TIstr);	/* termcap(5) says this is not padded */
307 	if (tstp != SIG_IGN)
308 		(void) signal(SIGTSTP, scr_stop);
309 	if (ttou != SIG_IGN)
310 		(void) signal(SIGTTOU, ttou);
311 
312 	isset = 1;
313 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
314 	scr_clear();
315 }
316 
317 /*
318  * End screen mode.
319  */
320 void
321 scr_end()
322 {
323 	sigset_t sigset, osigset;
324 
325 	sigemptyset(&sigset);
326 	sigaddset(&sigset, SIGTSTP);
327 	sigaddset(&sigset, SIGTTOU);
328 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
329 	/* move cursor to last line */
330 	if (LLstr)
331 		putstr(LLstr);	/* termcap(5) says this is not padded */
332 	else
333 		moveto(Rows - 1, 0);
334 	/* exit screen mode */
335 	if (TEstr)
336 		putstr(TEstr);	/* termcap(5) says this is not padded */
337 	(void) fflush(stdout);
338 	(void) tcsetattr(0, TCSADRAIN, &oldtt);
339 	isset = 0;
340 	/* restore signals */
341 	(void) signal(SIGTSTP, tstp);
342 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
343 }
344 
345 void
346 stop(why)
347 	const char *why;
348 {
349 
350 	if (isset)
351 		scr_end();
352 	(void) fprintf(stderr, "aborting: %s\n", why);
353 	exit(1);
354 }
355 
356 /*
357  * Clear the screen, forgetting the current contents in the process.
358  */
359 void
360 scr_clear()
361 {
362 
363 	putpad(CLstr);
364 	curscore = -1;
365 	memset((char *)curscreen, 0, sizeof(curscreen));
366 }
367 
368 #if vax && !__GNUC__
369 typedef int regcell;	/* pcc is bad at `register char', etc */
370 #else
371 typedef cell regcell;
372 #endif
373 
374 /*
375  * Update the screen.
376  */
377 void
378 scr_update()
379 {
380 	cell *bp, *sp;
381 	regcell so, cur_so = 0;
382 	int i, ccol, j;
383 	sigset_t sigset, osigset;
384 	static const struct shape *lastshape;
385 
386 	sigemptyset(&sigset);
387 	sigaddset(&sigset, SIGTSTP);
388 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
389 
390 	/* always leave cursor after last displayed point */
391 	curscreen[D_LAST * B_COLS - 1] = -1;
392 
393 	if (score != curscore) {
394 		if (HOstr)
395 			putpad(HOstr);
396 		else
397 			moveto(0, 0);
398 		(void) printf("Score: %d", score);
399 		curscore = score;
400 	}
401 
402 	/* draw preview of nextpattern */
403 	if (showpreview && (nextshape != lastshape)) {
404 		int i;
405 		static int r=5, c=2;
406 		int tr, tc, t;
407 
408 		lastshape = nextshape;
409 
410 		/* clean */
411 		putpad(SEstr);
412 		moveto(r-1, c-1); putstr("          ");
413 		moveto(r,   c-1); putstr("          ");
414 		moveto(r+1, c-1); putstr("          ");
415 		moveto(r+2, c-1); putstr("          ");
416 
417 		moveto(r-3, c-2);
418 		putstr("Next shape:");
419 
420 		/* draw */
421 		putpad(SOstr);
422 		moveto(r, 2*c);
423 		putstr("  ");
424 		for(i=0; i<3; i++) {
425 			t = c + r*B_COLS;
426 			t += nextshape->off[i];
427 
428 			tr = t / B_COLS;
429 			tc = t % B_COLS;
430 
431 			moveto(tr, 2*tc);
432 			putstr("  ");
433 		}
434 		putpad(SEstr);
435 	}
436 
437 	bp = &board[D_FIRST * B_COLS];
438 	sp = &curscreen[D_FIRST * B_COLS];
439 	for (j = D_FIRST; j < D_LAST; j++) {
440 		ccol = -1;
441 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
442 			if (*sp == (so = *bp))
443 				continue;
444 			*sp = so;
445 			if (i != ccol) {
446 				if (cur_so && MSflag) {
447 					putpad(SEstr);
448 					cur_so = 0;
449 				}
450 				moveto(RTOD(j), CTOD(i));
451 			}
452 			if (SOstr) {
453 				if (so != cur_so) {
454 					putpad(so ? SOstr : SEstr);
455 					cur_so = so;
456 				}
457 				putstr("  ");
458 			} else
459 				putstr(so ? "XX" : "  ");
460 			ccol = i + 1;
461 			/*
462 			 * Look ahead a bit, to avoid extra motion if
463 			 * we will be redrawing the cell after the next.
464 			 * Motion probably takes four or more characters,
465 			 * so we save even if we rewrite two cells
466 			 * `unnecessarily'.  Skip it all, though, if
467 			 * the next cell is a different color.
468 			 */
469 #define	STOP (B_COLS - 3)
470 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
471 				continue;
472 			if (sp[2] != bp[2])
473 				sp[1] = -1;
474 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
475 				sp[2] = -1;
476 				sp[1] = -1;
477 			}
478 		}
479 	}
480 	if (cur_so)
481 		putpad(SEstr);
482 	(void) fflush(stdout);
483 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
484 }
485 
486 /*
487  * Write a message (set!=0), or clear the same message (set==0).
488  * (We need its length in case we have to overwrite with blanks.)
489  */
490 void
491 scr_msg(s, set)
492 	char *s;
493 	int set;
494 {
495 
496 	if (set || CEstr == NULL) {
497 		int l = strlen(s);
498 
499 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
500 		if (set)
501 			putstr(s);
502 		else
503 			while (--l >= 0)
504 				(void) putchar(' ');
505 	} else {
506 		moveto(Rows - 2, 0);
507 		putpad(CEstr);
508 	}
509 }
510