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screen.c revision 1.18 
      1 /*	$NetBSD: screen.c,v 1.18 2003/08/07 09:37:48 agc 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/ioctl.h>
     42 
     43 #include <setjmp.h>
     44 #include <signal.h>
     45 #include <stdio.h>
     46 #include <stdlib.h>
     47 #include <string.h>
     48 #include <termcap.h>
     49 #include <termios.h>
     50 #include <unistd.h>
     51 
     52 #ifndef sigmask
     53 #define sigmask(s) (1 << ((s) - 1))
     54 #endif
     55 
     56 #include "screen.h"
     57 #include "tetris.h"
     58 
     59 static cell curscreen[B_SIZE];	/* 1 => standout (or otherwise marked) */
     60 static int curscore;
     61 static int isset;		/* true => terminal is in game mode */
     62 static struct termios oldtt;
     63 static void (*tstp) __P((int));
     64 
     65 static	void	scr_stop __P((int));
     66 static	void	stopset __P((int)) __attribute__((__noreturn__));
     67 
     68 
     69 /*
     70  * Capabilities from TERMCAP.
     71  */
     72 short	ospeed;
     73 
     74 static char
     75 	*bcstr,			/* backspace char */
     76 	*CEstr,			/* clear to end of line */
     77 	*CLstr,			/* clear screen */
     78 	*CMstr,			/* cursor motion string */
     79 #ifdef unneeded
     80 	*CRstr,			/* "\r" equivalent */
     81 #endif
     82 	*HOstr,			/* cursor home */
     83 	*LLstr,			/* last line, first column */
     84 	*pcstr,			/* pad character */
     85 	*TEstr,			/* end cursor motion mode */
     86 	*TIstr;			/* begin cursor motion mode */
     87 char
     88 	*SEstr,			/* end standout mode */
     89 	*SOstr;			/* begin standout mode */
     90 static int
     91 	COnum,			/* co# value */
     92 	LInum,			/* li# value */
     93 	MSflag;			/* can move in standout mode */
     94 
     95 
     96 struct tcsinfo {	/* termcap string info; some abbrevs above */
     97 	char tcname[3];
     98 	char **tcaddr;
     99 } tcstrings[] = {
    100 	{"bc", &bcstr},
    101 	{"ce", &CEstr},
    102 	{"cl", &CLstr},
    103 	{"cm", &CMstr},
    104 #ifdef unneeded
    105 	{"cr", &CRstr},
    106 #endif
    107 	{"le", &BC},		/* move cursor left one space */
    108 	{"pc", &pcstr},
    109 	{"se", &SEstr},
    110 	{"so", &SOstr},
    111 	{"te", &TEstr},
    112 	{"ti", &TIstr},
    113 	{"up", &UP},		/* cursor up */
    114 	{ {0}, NULL}
    115 };
    116 
    117 /* This is where we will actually stuff the information */
    118 
    119 static struct tinfo *info;
    120 
    121 /*
    122  * Routine used by tputs().
    123  */
    124 int
    125 put(c)
    126 	int c;
    127 {
    128 
    129 	return (putchar(c));
    130 }
    131 
    132 /*
    133  * putstr() is for unpadded strings (either as in termcap(5) or
    134  * simply literal strings); putpad() is for padded strings with
    135  * count=1.  (See screen.h for putpad().)
    136  */
    137 #define	putstr(s)	(void)fputs(s, stdout)
    138 
    139 void
    140 moveto(int r, int c)
    141 {
    142 	char buf[256];
    143 
    144 	if (t_goto(info, CMstr, c, r, buf, 255) == 0)
    145 		putpad(buf);
    146 }
    147 
    148 /*
    149  * Set up from termcap.
    150  */
    151 void
    152 scr_init()
    153 {
    154 	static int bsflag, xsflag, sgnum;
    155 #ifdef unneeded
    156 	static int ncflag;
    157 #endif
    158 	char *term;
    159 	static struct tcninfo {	/* termcap numeric and flag info */
    160 		char tcname[3];
    161 		int *tcaddr;
    162 	} tcflags[] = {
    163 		{"bs", &bsflag},
    164 		{"ms", &MSflag},
    165 #ifdef unneeded
    166 		{"nc", &ncflag},
    167 #endif
    168 		{"xs", &xsflag},
    169 		{ {0}, NULL}
    170 	}, tcnums[] = {
    171 		{"co", &COnum},
    172 		{"li", &LInum},
    173 		{"sg", &sgnum},
    174 		{ {0}, NULL}
    175 	};
    176 
    177 	if ((term = getenv("TERM")) == NULL)
    178 		stop("you must set the TERM environment variable");
    179 	if (t_getent(&info, term) <= 0)
    180 		stop("cannot find your termcap");
    181 	{
    182 		struct tcsinfo *p;
    183 
    184 		for (p = tcstrings; p->tcaddr; p++)
    185 			*p->tcaddr = t_agetstr(info, p->tcname);
    186 	}
    187 	{
    188 		struct tcninfo *p;
    189 
    190 		for (p = tcflags; p->tcaddr; p++)
    191 			*p->tcaddr = t_getflag(info, p->tcname);
    192 		for (p = tcnums; p->tcaddr; p++)
    193 			*p->tcaddr = t_getnum(info, p->tcname);
    194 	}
    195 	if (bsflag)
    196 		BC = "\b";
    197 	else if (BC == NULL && bcstr != NULL)
    198 		BC = bcstr;
    199 	if (CLstr == NULL)
    200 		stop("cannot clear screen");
    201 	if (CMstr == NULL || UP == NULL || BC == NULL)
    202 		stop("cannot do random cursor positioning via tgoto()");
    203 	PC = pcstr ? *pcstr : 0;
    204 	if (sgnum >= 0 || xsflag)
    205 		SOstr = SEstr = NULL;
    206 #ifdef unneeded
    207 	if (ncflag)
    208 		CRstr = NULL;
    209 	else if (CRstr == NULL)
    210 		CRstr = "\r";
    211 #endif
    212 }
    213 
    214 /* this foolery is needed to modify tty state `atomically' */
    215 static jmp_buf scr_onstop;
    216 
    217 static void
    218 stopset(sig)
    219 	int sig;
    220 {
    221 	sigset_t sigset;
    222 
    223 	(void) signal(sig, SIG_DFL);
    224 	(void) kill(getpid(), sig);
    225 	sigemptyset(&sigset);
    226 	sigaddset(&sigset, sig);
    227 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
    228 	longjmp(scr_onstop, 1);
    229 }
    230 
    231 static void
    232 scr_stop(sig)
    233 	int sig;
    234 {
    235 	sigset_t sigset;
    236 
    237 	scr_end();
    238 	(void) kill(getpid(), sig);
    239 	sigemptyset(&sigset);
    240 	sigaddset(&sigset, sig);
    241 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
    242 	scr_set();
    243 	scr_msg(key_msg, 1);
    244 }
    245 
    246 /*
    247  * Set up screen mode.
    248  */
    249 void
    250 scr_set()
    251 {
    252 	struct winsize ws;
    253 	struct termios newtt;
    254 	sigset_t sigset, osigset;
    255 	void (*ttou) __P((int));
    256 
    257 	sigemptyset(&sigset);
    258 	sigaddset(&sigset, SIGTSTP);
    259 	sigaddset(&sigset, SIGTTOU);
    260 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    261 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
    262 		(void) signal(SIGTSTP, SIG_IGN);
    263 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
    264 		(void) signal(SIGTTOU, SIG_IGN);
    265 	/*
    266 	 * At last, we are ready to modify the tty state.  If
    267 	 * we stop while at it, stopset() above will longjmp back
    268 	 * to the setjmp here and we will start over.
    269 	 */
    270 	(void) setjmp(scr_onstop);
    271 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    272 	Rows = 0, Cols = 0;
    273 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
    274 		Rows = ws.ws_row;
    275 		Cols = ws.ws_col;
    276 	}
    277 	if (Rows == 0)
    278 		Rows = LInum;
    279 	if (Cols == 0)
    280 	Cols = COnum;
    281 	if (Rows < MINROWS || Cols < MINCOLS) {
    282 		(void) fprintf(stderr,
    283 		    "the screen is too small: must be at least %dx%d, ",
    284 		    MINCOLS, MINROWS);
    285 		stop("");	/* stop() supplies \n */
    286 	}
    287 	if (tcgetattr(0, &oldtt) < 0)
    288 		stop("tcgetattr() fails");
    289 	newtt = oldtt;
    290 	newtt.c_lflag &= ~(ICANON|ECHO);
    291 	newtt.c_oflag &= ~OXTABS;
    292 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
    293 		stop("tcsetattr() fails");
    294 	ospeed = cfgetospeed(&newtt);
    295 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    296 
    297 	/*
    298 	 * We made it.  We are now in screen mode, modulo TIstr
    299 	 * (which we will fix immediately).
    300 	 */
    301 	if (TIstr)
    302 		putstr(TIstr);	/* termcap(5) says this is not padded */
    303 	if (tstp != SIG_IGN)
    304 		(void) signal(SIGTSTP, scr_stop);
    305 	if (ttou != SIG_IGN)
    306 		(void) signal(SIGTTOU, ttou);
    307 
    308 	isset = 1;
    309 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    310 	scr_clear();
    311 }
    312 
    313 /*
    314  * End screen mode.
    315  */
    316 void
    317 scr_end()
    318 {
    319 	sigset_t sigset, osigset;
    320 
    321 	sigemptyset(&sigset);
    322 	sigaddset(&sigset, SIGTSTP);
    323 	sigaddset(&sigset, SIGTTOU);
    324 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    325 	/* move cursor to last line */
    326 	if (LLstr)
    327 		putstr(LLstr);	/* termcap(5) says this is not padded */
    328 	else
    329 		moveto(Rows - 1, 0);
    330 	/* exit screen mode */
    331 	if (TEstr)
    332 		putstr(TEstr);	/* termcap(5) says this is not padded */
    333 	(void) fflush(stdout);
    334 	(void) tcsetattr(0, TCSADRAIN, &oldtt);
    335 	isset = 0;
    336 	/* restore signals */
    337 	(void) signal(SIGTSTP, tstp);
    338 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    339 }
    340 
    341 void
    342 stop(why)
    343 	const char *why;
    344 {
    345 
    346 	if (isset)
    347 		scr_end();
    348 	(void) fprintf(stderr, "aborting: %s\n", why);
    349 	exit(1);
    350 }
    351 
    352 /*
    353  * Clear the screen, forgetting the current contents in the process.
    354  */
    355 void
    356 scr_clear()
    357 {
    358 
    359 	putpad(CLstr);
    360 	curscore = -1;
    361 	memset((char *)curscreen, 0, sizeof(curscreen));
    362 }
    363 
    364 #if vax && !__GNUC__
    365 typedef int regcell;	/* pcc is bad at `register char', etc */
    366 #else
    367 typedef cell regcell;
    368 #endif
    369 
    370 /*
    371  * Update the screen.
    372  */
    373 void
    374 scr_update()
    375 {
    376 	cell *bp, *sp;
    377 	regcell so, cur_so = 0;
    378 	int i, ccol, j;
    379 	sigset_t sigset, osigset;
    380 	static const struct shape *lastshape;
    381 
    382 	sigemptyset(&sigset);
    383 	sigaddset(&sigset, SIGTSTP);
    384 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    385 
    386 	/* always leave cursor after last displayed point */
    387 	curscreen[D_LAST * B_COLS - 1] = -1;
    388 
    389 	if (score != curscore) {
    390 		if (HOstr)
    391 			putpad(HOstr);
    392 		else
    393 			moveto(0, 0);
    394 		(void) printf("Score: %d", score);
    395 		curscore = score;
    396 	}
    397 
    398 	/* draw preview of nextpattern */
    399 	if (showpreview && (nextshape != lastshape)) {
    400 		int i;
    401 		static int r=5, c=2;
    402 		int tr, tc, t;
    403 
    404 		lastshape = nextshape;
    405 
    406 		/* clean */
    407 		putpad(SEstr);
    408 		moveto(r-1, c-1); putstr("          ");
    409 		moveto(r,   c-1); putstr("          ");
    410 		moveto(r+1, c-1); putstr("          ");
    411 		moveto(r+2, c-1); putstr("          ");
    412 
    413 		moveto(r-3, c-2);
    414 		putstr("Next shape:");
    415 
    416 		/* draw */
    417 		putpad(SOstr);
    418 		moveto(r, 2*c);
    419 		putstr("  ");
    420 		for(i=0; i<3; i++) {
    421 			t = c + r*B_COLS;
    422 			t += nextshape->off[i];
    423 
    424 			tr = t / B_COLS;
    425 			tc = t % B_COLS;
    426 
    427 			moveto(tr, 2*tc);
    428 			putstr("  ");
    429 		}
    430 		putpad(SEstr);
    431 	}
    432 
    433 	bp = &board[D_FIRST * B_COLS];
    434 	sp = &curscreen[D_FIRST * B_COLS];
    435 	for (j = D_FIRST; j < D_LAST; j++) {
    436 		ccol = -1;
    437 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
    438 			if (*sp == (so = *bp))
    439 				continue;
    440 			*sp = so;
    441 			if (i != ccol) {
    442 				if (cur_so && MSflag) {
    443 					putpad(SEstr);
    444 					cur_so = 0;
    445 				}
    446 				moveto(RTOD(j), CTOD(i));
    447 			}
    448 			if (SOstr) {
    449 				if (so != cur_so) {
    450 					putpad(so ? SOstr : SEstr);
    451 					cur_so = so;
    452 				}
    453 				putstr("  ");
    454 			} else
    455 				putstr(so ? "XX" : "  ");
    456 			ccol = i + 1;
    457 			/*
    458 			 * Look ahead a bit, to avoid extra motion if
    459 			 * we will be redrawing the cell after the next.
    460 			 * Motion probably takes four or more characters,
    461 			 * so we save even if we rewrite two cells
    462 			 * `unnecessarily'.  Skip it all, though, if
    463 			 * the next cell is a different color.
    464 			 */
    465 #define	STOP (B_COLS - 3)
    466 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
    467 				continue;
    468 			if (sp[2] != bp[2])
    469 				sp[1] = -1;
    470 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
    471 				sp[2] = -1;
    472 				sp[1] = -1;
    473 			}
    474 		}
    475 	}
    476 	if (cur_so)
    477 		putpad(SEstr);
    478 	(void) fflush(stdout);
    479 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    480 }
    481 
    482 /*
    483  * Write a message (set!=0), or clear the same message (set==0).
    484  * (We need its length in case we have to overwrite with blanks.)
    485  */
    486 void
    487 scr_msg(s, set)
    488 	char *s;
    489 	int set;
    490 {
    491 
    492 	if (set || CEstr == NULL) {
    493 		int l = strlen(s);
    494 
    495 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
    496 		if (set)
    497 			putstr(s);
    498 		else
    499 			while (--l >= 0)
    500 				(void) putchar(' ');
    501 	} else {
    502 		moveto(Rows - 2, 0);
    503 		putpad(CEstr);
    504 	}
    505 }
    506