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screen.c revision 1.14 
      1 /*	$NetBSD: screen.c,v 1.14 2000/05/22 12:42:47 blymn 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 char *combuf;
    124 static struct tinfo *info;
    125 
    126 /*
    127  * Routine used by tputs().
    128  */
    129 int
    130 put(c)
    131 	int c;
    132 {
    133 
    134 	return (putchar(c));
    135 }
    136 
    137 /*
    138  * putstr() is for unpadded strings (either as in termcap(5) or
    139  * simply literal strings); putpad() is for padded strings with
    140  * count=1.  (See screen.h for putpad().)
    141  */
    142 #define	putstr(s)	(void)fputs(s, stdout)
    143 
    144 void
    145 moveto(int r, int c)
    146 {
    147 	char buf[256];
    148 
    149 	if (t_goto(info, CMstr, c, r, buf, 255) == 0)
    150 		putpad(buf);
    151 }
    152 
    153 /*
    154  * Set up from termcap.
    155  */
    156 void
    157 scr_init()
    158 {
    159 	static int bsflag, xsflag, sgnum;
    160 #ifdef unneeded
    161 	static int ncflag;
    162 #endif
    163 	char *term, *fill;
    164 	static struct tcninfo {	/* termcap numeric and flag info */
    165 		char tcname[3];
    166 		int *tcaddr;
    167 	} tcflags[] = {
    168 		{"bs", &bsflag},
    169 		{"ms", &MSflag},
    170 #ifdef unneeded
    171 		{"nc", &ncflag},
    172 #endif
    173 		{"xs", &xsflag},
    174 		{ {0}, NULL}
    175 	}, tcnums[] = {
    176 		{"co", &COnum},
    177 		{"li", &LInum},
    178 		{"sg", &sgnum},
    179 		{ {0}, NULL}
    180 	};
    181 
    182 	if ((term = getenv("TERM")) == NULL)
    183 		stop("you must set the TERM environment variable");
    184 	if (t_getent(&info, term) <= 0)
    185 		stop("cannot find your termcap");
    186 	*combuf = NULL;
    187 	{
    188 		register struct tcsinfo *p;
    189 
    190 		for (p = tcstrings; p->tcaddr; p++)
    191 			*p->tcaddr = t_agetstr(info, p->tcname, &combuf,
    192 					       &fill);
    193 	}
    194 	{
    195 		register struct tcninfo *p;
    196 
    197 		for (p = tcflags; p->tcaddr; p++)
    198 			*p->tcaddr = t_getflag(info, p->tcname);
    199 		for (p = tcnums; p->tcaddr; p++)
    200 			*p->tcaddr = t_getnum(info, p->tcname);
    201 	}
    202 	if (bsflag)
    203 		BC = "\b";
    204 	else if (BC == NULL && bcstr != NULL)
    205 		BC = bcstr;
    206 	if (CLstr == NULL)
    207 		stop("cannot clear screen");
    208 	if (CMstr == NULL || UP == NULL || BC == NULL)
    209 		stop("cannot do random cursor positioning via tgoto()");
    210 	PC = pcstr ? *pcstr : 0;
    211 	if (sgnum >= 0 || xsflag)
    212 		SOstr = SEstr = NULL;
    213 #ifdef unneeded
    214 	if (ncflag)
    215 		CRstr = NULL;
    216 	else if (CRstr == NULL)
    217 		CRstr = "\r";
    218 #endif
    219 }
    220 
    221 /* this foolery is needed to modify tty state `atomically' */
    222 static jmp_buf scr_onstop;
    223 
    224 static void
    225 stopset(sig)
    226 	int sig;
    227 {
    228 	sigset_t sigset;
    229 
    230 	(void) signal(sig, SIG_DFL);
    231 	(void) kill(getpid(), sig);
    232 	sigemptyset(&sigset);
    233 	sigaddset(&sigset, sig);
    234 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
    235 	longjmp(scr_onstop, 1);
    236 }
    237 
    238 static void
    239 scr_stop(sig)
    240 	int sig;
    241 {
    242 	sigset_t sigset;
    243 
    244 	scr_end();
    245 	(void) kill(getpid(), sig);
    246 	sigemptyset(&sigset);
    247 	sigaddset(&sigset, sig);
    248 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
    249 	scr_set();
    250 	scr_msg(key_msg, 1);
    251 }
    252 
    253 /*
    254  * Set up screen mode.
    255  */
    256 void
    257 scr_set()
    258 {
    259 	struct winsize ws;
    260 	struct termios newtt;
    261 	sigset_t sigset, osigset;
    262 	void (*ttou) __P((int));
    263 
    264 	sigemptyset(&sigset);
    265 	sigaddset(&sigset, SIGTSTP);
    266 	sigaddset(&sigset, SIGTTOU);
    267 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    268 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
    269 		(void) signal(SIGTSTP, SIG_IGN);
    270 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
    271 		(void) signal(SIGTTOU, SIG_IGN);
    272 	/*
    273 	 * At last, we are ready to modify the tty state.  If
    274 	 * we stop while at it, stopset() above will longjmp back
    275 	 * to the setjmp here and we will start over.
    276 	 */
    277 	(void) setjmp(scr_onstop);
    278 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    279 	Rows = 0, Cols = 0;
    280 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
    281 		Rows = ws.ws_row;
    282 		Cols = ws.ws_col;
    283 	}
    284 	if (Rows == 0)
    285 		Rows = LInum;
    286 	if (Cols == 0)
    287 	Cols = COnum;
    288 	if (Rows < MINROWS || Cols < MINCOLS) {
    289 		(void) fprintf(stderr,
    290 		    "the screen is too small: must be at least %dx%d, ",
    291 		    MINCOLS, MINROWS);
    292 		stop("");	/* stop() supplies \n */
    293 	}
    294 	if (tcgetattr(0, &oldtt) < 0)
    295 		stop("tcgetattr() fails");
    296 	newtt = oldtt;
    297 	newtt.c_lflag &= ~(ICANON|ECHO);
    298 	newtt.c_oflag &= ~OXTABS;
    299 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
    300 		stop("tcsetattr() fails");
    301 	ospeed = cfgetospeed(&newtt);
    302 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    303 
    304 	/*
    305 	 * We made it.  We are now in screen mode, modulo TIstr
    306 	 * (which we will fix immediately).
    307 	 */
    308 	if (TIstr)
    309 		putstr(TIstr);	/* termcap(5) says this is not padded */
    310 	if (tstp != SIG_IGN)
    311 		(void) signal(SIGTSTP, scr_stop);
    312 	if (ttou != SIG_IGN)
    313 		(void) signal(SIGTTOU, ttou);
    314 
    315 	isset = 1;
    316 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    317 	scr_clear();
    318 }
    319 
    320 /*
    321  * End screen mode.
    322  */
    323 void
    324 scr_end()
    325 {
    326 	sigset_t sigset, osigset;
    327 
    328 	sigemptyset(&sigset);
    329 	sigaddset(&sigset, SIGTSTP);
    330 	sigaddset(&sigset, SIGTTOU);
    331 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    332 	/* move cursor to last line */
    333 	if (LLstr)
    334 		putstr(LLstr);	/* termcap(5) says this is not padded */
    335 	else
    336 		moveto(Rows - 1, 0);
    337 	/* exit screen mode */
    338 	if (TEstr)
    339 		putstr(TEstr);	/* termcap(5) says this is not padded */
    340 	(void) fflush(stdout);
    341 	(void) tcsetattr(0, TCSADRAIN, &oldtt);
    342 	isset = 0;
    343 	/* restore signals */
    344 	(void) signal(SIGTSTP, tstp);
    345 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    346 }
    347 
    348 void
    349 stop(why)
    350 	const char *why;
    351 {
    352 
    353 	if (isset)
    354 		scr_end();
    355 	(void) fprintf(stderr, "aborting: %s\n", why);
    356 	exit(1);
    357 }
    358 
    359 /*
    360  * Clear the screen, forgetting the current contents in the process.
    361  */
    362 void
    363 scr_clear()
    364 {
    365 
    366 	putpad(CLstr);
    367 	curscore = -1;
    368 	memset((char *)curscreen, 0, sizeof(curscreen));
    369 }
    370 
    371 #if vax && !__GNUC__
    372 typedef int regcell;	/* pcc is bad at `register char', etc */
    373 #else
    374 typedef cell regcell;
    375 #endif
    376 
    377 /*
    378  * Update the screen.
    379  */
    380 void
    381 scr_update()
    382 {
    383 	register cell *bp, *sp;
    384 	register regcell so, cur_so = 0;
    385 	register int i, ccol, j;
    386 	sigset_t sigset, osigset;
    387 	static const struct shape *lastshape;
    388 
    389 	sigemptyset(&sigset);
    390 	sigaddset(&sigset, SIGTSTP);
    391 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    392 
    393 	/* always leave cursor after last displayed point */
    394 	curscreen[D_LAST * B_COLS - 1] = -1;
    395 
    396 	if (score != curscore) {
    397 		if (HOstr)
    398 			putpad(HOstr);
    399 		else
    400 			moveto(0, 0);
    401 		(void) printf("Score: %d", score);
    402 		curscore = score;
    403 	}
    404 
    405 	/* draw preview of nextpattern */
    406 	if (showpreview && (nextshape != lastshape)) {
    407 		int i;
    408 		static int r=5, c=2;
    409 		int tr, tc, t;
    410 
    411 		lastshape = nextshape;
    412 
    413 		/* clean */
    414 		putpad(SEstr);
    415 		moveto(r-1, c-1); putstr("          ");
    416 		moveto(r,   c-1); putstr("          ");
    417 		moveto(r+1, c-1); putstr("          ");
    418 		moveto(r+2, c-1); putstr("          ");
    419 
    420 		moveto(r-3, c-2);
    421 		putstr("Next shape:");
    422 
    423 		/* draw */
    424 		putpad(SOstr);
    425 		moveto(r, 2*c);
    426 		putstr("  ");
    427 		for(i=0; i<3; i++) {
    428 			t = c + r*B_COLS;
    429 			t += nextshape->off[i];
    430 
    431 			tr = t / B_COLS;
    432 			tc = t % B_COLS;
    433 
    434 			moveto(tr, 2*tc);
    435 			putstr("  ");
    436 		}
    437 		putpad(SEstr);
    438 	}
    439 
    440 	bp = &board[D_FIRST * B_COLS];
    441 	sp = &curscreen[D_FIRST * B_COLS];
    442 	for (j = D_FIRST; j < D_LAST; j++) {
    443 		ccol = -1;
    444 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
    445 			if (*sp == (so = *bp))
    446 				continue;
    447 			*sp = so;
    448 			if (i != ccol) {
    449 				if (cur_so && MSflag) {
    450 					putpad(SEstr);
    451 					cur_so = 0;
    452 				}
    453 				moveto(RTOD(j), CTOD(i));
    454 			}
    455 			if (SOstr) {
    456 				if (so != cur_so) {
    457 					putpad(so ? SOstr : SEstr);
    458 					cur_so = so;
    459 				}
    460 				putstr("  ");
    461 			} else
    462 				putstr(so ? "XX" : "  ");
    463 			ccol = i + 1;
    464 			/*
    465 			 * Look ahead a bit, to avoid extra motion if
    466 			 * we will be redrawing the cell after the next.
    467 			 * Motion probably takes four or more characters,
    468 			 * so we save even if we rewrite two cells
    469 			 * `unnecessarily'.  Skip it all, though, if
    470 			 * the next cell is a different color.
    471 			 */
    472 #define	STOP (B_COLS - 3)
    473 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
    474 				continue;
    475 			if (sp[2] != bp[2])
    476 				sp[1] = -1;
    477 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
    478 				sp[2] = -1;
    479 				sp[1] = -1;
    480 			}
    481 		}
    482 	}
    483 	if (cur_so)
    484 		putpad(SEstr);
    485 	(void) fflush(stdout);
    486 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    487 }
    488 
    489 /*
    490  * Write a message (set!=0), or clear the same message (set==0).
    491  * (We need its length in case we have to overwrite with blanks.)
    492  */
    493 void
    494 scr_msg(s, set)
    495 	register char *s;
    496 	int set;
    497 {
    498 
    499 	if (set || CEstr == NULL) {
    500 		register int l = strlen(s);
    501 
    502 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
    503 		if (set)
    504 			putstr(s);
    505 		else
    506 			while (--l >= 0)
    507 				(void) putchar(' ');
    508 	} else {
    509 		moveto(Rows - 2, 0);
    510 		putpad(CEstr);
    511 	}
    512 }
    513