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screen.c revision 1.16 
      1 /*	$NetBSD: screen.c,v 1.16 2001/11/02 18:27:00 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. 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 		register struct tcsinfo *p;
    187 
    188 		for (p = tcstrings; p->tcaddr; p++)
    189 			*p->tcaddr = t_agetstr(info, p->tcname);
    190 	}
    191 	{
    192 		register 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 	register cell *bp, *sp;
    381 	register regcell so, cur_so = 0;
    382 	register 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 	register char *s;
    493 	int set;
    494 {
    495 
    496 	if (set || CEstr == NULL) {
    497 		register 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