Home | History | Annotate | Line # | Download | only in tetris
screen.c revision 1.21 
      1 /*	$NetBSD: screen.c,v 1.21 2007/12/15 19:44:43 perry 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 <termcap.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  * Capabilities from TERMCAP.
     72  */
     73 short	ospeed;
     74 
     75 static char
     76 	*bcstr,			/* backspace char */
     77 	*CEstr,			/* clear to end of line */
     78 	*CLstr,			/* clear screen */
     79 	*CMstr,			/* cursor motion string */
     80 #ifdef unneeded
     81 	*CRstr,			/* "\r" equivalent */
     82 #endif
     83 	*HOstr,			/* cursor home */
     84 	*LLstr,			/* last line, first column */
     85 	*pcstr,			/* pad character */
     86 	*TEstr,			/* end cursor motion mode */
     87 	*TIstr;			/* begin cursor motion mode */
     88 char
     89 	*SEstr,			/* end standout mode */
     90 	*SOstr;			/* begin standout mode */
     91 static int
     92 	COnum,			/* co# value */
     93 	LInum,			/* li# value */
     94 	MSflag;			/* can move in standout mode */
     95 
     96 
     97 struct tcsinfo {	/* termcap string info; some abbrevs above */
     98 	char tcname[3];
     99 	char **tcaddr;
    100 } tcstrings[] = {
    101 	{"bc", &bcstr},
    102 	{"ce", &CEstr},
    103 	{"cl", &CLstr},
    104 	{"cm", &CMstr},
    105 #ifdef unneeded
    106 	{"cr", &CRstr},
    107 #endif
    108 	{"le", &BC},		/* move cursor left one space */
    109 	{"pc", &pcstr},
    110 	{"se", &SEstr},
    111 	{"so", &SOstr},
    112 	{"te", &TEstr},
    113 	{"ti", &TIstr},
    114 	{"up", &UP},		/* cursor up */
    115 	{ {0}, NULL}
    116 };
    117 
    118 /* This is where we will actually stuff the information */
    119 
    120 static struct tinfo *info;
    121 
    122 /*
    123  * Routine used by tputs().
    124  */
    125 int
    126 put(c)
    127 	int c;
    128 {
    129 
    130 	return (putchar(c));
    131 }
    132 
    133 /*
    134  * putstr() is for unpadded strings (either as in termcap(5) or
    135  * simply literal strings); putpad() is for padded strings with
    136  * count=1.  (See screen.h for putpad().)
    137  */
    138 #define	putstr(s)	(void)fputs(s, stdout)
    139 
    140 void
    141 moveto(int r, int c)
    142 {
    143 	char buf[256];
    144 
    145 	if (t_goto(info, CMstr, c, r, buf, 255) == 0)
    146 		putpad(buf);
    147 }
    148 
    149 /*
    150  * Set up from termcap.
    151  */
    152 void
    153 scr_init()
    154 {
    155 	static int bsflag, xsflag, sgnum;
    156 #ifdef unneeded
    157 	static int ncflag;
    158 #endif
    159 	char *term;
    160 	static struct tcninfo {	/* termcap numeric and flag info */
    161 		char tcname[3];
    162 		int *tcaddr;
    163 	} tcflags[] = {
    164 		{"bs", &bsflag},
    165 		{"ms", &MSflag},
    166 #ifdef unneeded
    167 		{"nc", &ncflag},
    168 #endif
    169 		{"xs", &xsflag},
    170 		{ {0}, NULL}
    171 	}, tcnums[] = {
    172 		{"co", &COnum},
    173 		{"li", &LInum},
    174 		{"sg", &sgnum},
    175 		{ {0}, NULL}
    176 	};
    177 
    178 	if ((term = getenv("TERM")) == NULL)
    179 		stop("you must set the TERM environment variable");
    180 	if (t_getent(&info, term) <= 0)
    181 		stop("cannot find your termcap");
    182 	{
    183 		struct tcsinfo *p;
    184 
    185 		for (p = tcstrings; p->tcaddr; p++)
    186 			*p->tcaddr = t_agetstr(info, p->tcname);
    187 	}
    188 	{
    189 		struct tcninfo *p;
    190 
    191 		for (p = tcflags; p->tcaddr; p++)
    192 			*p->tcaddr = t_getflag(info, p->tcname);
    193 		for (p = tcnums; p->tcaddr; p++)
    194 			*p->tcaddr = t_getnum(info, p->tcname);
    195 	}
    196 	if (bsflag)
    197 		BC = "\b";
    198 	else if (BC == NULL && bcstr != NULL)
    199 		BC = bcstr;
    200 	if (CLstr == NULL)
    201 		stop("cannot clear screen");
    202 	if (CMstr == NULL || UP == NULL || BC == NULL)
    203 		stop("cannot do random cursor positioning via tgoto()");
    204 	PC = pcstr ? *pcstr : 0;
    205 	if (sgnum >= 0 || xsflag)
    206 		SOstr = SEstr = NULL;
    207 #ifdef unneeded
    208 	if (ncflag)
    209 		CRstr = NULL;
    210 	else if (CRstr == NULL)
    211 		CRstr = "\r";
    212 #endif
    213 }
    214 
    215 /* this foolery is needed to modify tty state `atomically' */
    216 static jmp_buf scr_onstop;
    217 
    218 static void
    219 stopset(sig)
    220 	int sig;
    221 {
    222 	sigset_t sigset;
    223 
    224 	(void) signal(sig, SIG_DFL);
    225 	(void) kill(getpid(), sig);
    226 	sigemptyset(&sigset);
    227 	sigaddset(&sigset, sig);
    228 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
    229 	longjmp(scr_onstop, 1);
    230 }
    231 
    232 static void
    233 scr_stop(sig)
    234 	int sig;
    235 {
    236 	sigset_t sigset;
    237 
    238 	scr_end();
    239 	(void) kill(getpid(), sig);
    240 	sigemptyset(&sigset);
    241 	sigaddset(&sigset, sig);
    242 	(void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
    243 	scr_set();
    244 	scr_msg(key_msg, 1);
    245 }
    246 
    247 /*
    248  * Set up screen mode.
    249  */
    250 void
    251 scr_set()
    252 {
    253 	struct winsize ws;
    254 	struct termios newtt;
    255 	sigset_t sigset, osigset;
    256 	void (*ttou)(int);
    257 
    258 	sigemptyset(&sigset);
    259 	sigaddset(&sigset, SIGTSTP);
    260 	sigaddset(&sigset, SIGTTOU);
    261 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    262 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
    263 		(void) signal(SIGTSTP, SIG_IGN);
    264 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
    265 		(void) signal(SIGTTOU, SIG_IGN);
    266 	/*
    267 	 * At last, we are ready to modify the tty state.  If
    268 	 * we stop while at it, stopset() above will longjmp back
    269 	 * to the setjmp here and we will start over.
    270 	 */
    271 	(void) setjmp(scr_onstop);
    272 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    273 	Rows = 0, Cols = 0;
    274 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
    275 		Rows = ws.ws_row;
    276 		Cols = ws.ws_col;
    277 	}
    278 	if (Rows == 0)
    279 		Rows = LInum;
    280 	if (Cols == 0)
    281 	Cols = COnum;
    282 	if (Rows < MINROWS || Cols < MINCOLS) {
    283 		(void) fprintf(stderr,
    284 		    "the screen is too small: must be at least %dx%d, ",
    285 		    MINCOLS, MINROWS);
    286 		stop("");	/* stop() supplies \n */
    287 	}
    288 	if (tcgetattr(0, &oldtt) < 0)
    289 		stop("tcgetattr() fails");
    290 	newtt = oldtt;
    291 	newtt.c_lflag &= ~(ICANON|ECHO);
    292 	newtt.c_oflag &= ~OXTABS;
    293 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
    294 		stop("tcsetattr() fails");
    295 	ospeed = cfgetospeed(&newtt);
    296 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    297 
    298 	/*
    299 	 * We made it.  We are now in screen mode, modulo TIstr
    300 	 * (which we will fix immediately).
    301 	 */
    302 	if (TIstr)
    303 		putstr(TIstr);	/* termcap(5) says this is not padded */
    304 	if (tstp != SIG_IGN)
    305 		(void) signal(SIGTSTP, scr_stop);
    306 	if (ttou != SIG_IGN)
    307 		(void) signal(SIGTTOU, ttou);
    308 
    309 	isset = 1;
    310 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    311 	scr_clear();
    312 }
    313 
    314 /*
    315  * End screen mode.
    316  */
    317 void
    318 scr_end()
    319 {
    320 	sigset_t sigset, osigset;
    321 
    322 	sigemptyset(&sigset);
    323 	sigaddset(&sigset, SIGTSTP);
    324 	sigaddset(&sigset, SIGTTOU);
    325 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    326 	/* move cursor to last line */
    327 	if (LLstr)
    328 		putstr(LLstr);	/* termcap(5) says this is not padded */
    329 	else
    330 		moveto(Rows - 1, 0);
    331 	/* exit screen mode */
    332 	if (TEstr)
    333 		putstr(TEstr);	/* termcap(5) says this is not padded */
    334 	(void) fflush(stdout);
    335 	(void) tcsetattr(0, TCSADRAIN, &oldtt);
    336 	isset = 0;
    337 	/* restore signals */
    338 	(void) signal(SIGTSTP, tstp);
    339 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    340 }
    341 
    342 void
    343 stop(why)
    344 	const char *why;
    345 {
    346 
    347 	if (isset)
    348 		scr_end();
    349 	(void) fprintf(stderr, "aborting: %s\n", why);
    350 	exit(1);
    351 }
    352 
    353 /*
    354  * Clear the screen, forgetting the current contents in the process.
    355  */
    356 void
    357 scr_clear()
    358 {
    359 
    360 	putpad(CLstr);
    361 	curscore = -1;
    362 	memset((char *)curscreen, 0, sizeof(curscreen));
    363 }
    364 
    365 #if vax && !__GNUC__
    366 typedef int regcell;	/* pcc is bad at `register char', etc */
    367 #else
    368 typedef cell regcell;
    369 #endif
    370 
    371 /*
    372  * Update the screen.
    373  */
    374 void
    375 scr_update()
    376 {
    377 	cell *bp, *sp;
    378 	regcell so, cur_so = 0;
    379 	int i, ccol, j;
    380 	sigset_t sigset, osigset;
    381 	static const struct shape *lastshape;
    382 
    383 	sigemptyset(&sigset);
    384 	sigaddset(&sigset, SIGTSTP);
    385 	(void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
    386 
    387 	/* always leave cursor after last displayed point */
    388 	curscreen[D_LAST * B_COLS - 1] = -1;
    389 
    390 	if (score != curscore) {
    391 		if (HOstr)
    392 			putpad(HOstr);
    393 		else
    394 			moveto(0, 0);
    395 		(void) printf("Score: %d", score);
    396 		curscore = score;
    397 	}
    398 
    399 	/* draw preview of nextpattern */
    400 	if (showpreview && (nextshape != lastshape)) {
    401 		int i;
    402 		static int r=5, c=2;
    403 		int tr, tc, t;
    404 
    405 		lastshape = nextshape;
    406 
    407 		/* clean */
    408 		putpad(SEstr);
    409 		moveto(r-1, c-1); putstr("          ");
    410 		moveto(r,   c-1); putstr("          ");
    411 		moveto(r+1, c-1); putstr("          ");
    412 		moveto(r+2, c-1); putstr("          ");
    413 
    414 		moveto(r-3, c-2);
    415 		putstr("Next shape:");
    416 
    417 		/* draw */
    418 		putpad(SOstr);
    419 		moveto(r, 2*c);
    420 		putstr("  ");
    421 		for(i=0; i<3; i++) {
    422 			t = c + r*B_COLS;
    423 			t += nextshape->off[i];
    424 
    425 			tr = t / B_COLS;
    426 			tc = t % B_COLS;
    427 
    428 			moveto(tr, 2*tc);
    429 			putstr("  ");
    430 		}
    431 		putpad(SEstr);
    432 	}
    433 
    434 	bp = &board[D_FIRST * B_COLS];
    435 	sp = &curscreen[D_FIRST * B_COLS];
    436 	for (j = D_FIRST; j < D_LAST; j++) {
    437 		ccol = -1;
    438 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
    439 			if (*sp == (so = *bp))
    440 				continue;
    441 			*sp = so;
    442 			if (i != ccol) {
    443 				if (cur_so && MSflag) {
    444 					putpad(SEstr);
    445 					cur_so = 0;
    446 				}
    447 				moveto(RTOD(j), CTOD(i));
    448 			}
    449 			if (SOstr) {
    450 				if (so != cur_so) {
    451 					putpad(so ? SOstr : SEstr);
    452 					cur_so = so;
    453 				}
    454 				putstr("  ");
    455 			} else
    456 				putstr(so ? "XX" : "  ");
    457 			ccol = i + 1;
    458 			/*
    459 			 * Look ahead a bit, to avoid extra motion if
    460 			 * we will be redrawing the cell after the next.
    461 			 * Motion probably takes four or more characters,
    462 			 * so we save even if we rewrite two cells
    463 			 * `unnecessarily'.  Skip it all, though, if
    464 			 * the next cell is a different color.
    465 			 */
    466 #define	STOP (B_COLS - 3)
    467 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
    468 				continue;
    469 			if (sp[2] != bp[2])
    470 				sp[1] = -1;
    471 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
    472 				sp[2] = -1;
    473 				sp[1] = -1;
    474 			}
    475 		}
    476 	}
    477 	if (cur_so)
    478 		putpad(SEstr);
    479 	(void) fflush(stdout);
    480 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    481 }
    482 
    483 /*
    484  * Write a message (set!=0), or clear the same message (set==0).
    485  * (We need its length in case we have to overwrite with blanks.)
    486  */
    487 void
    488 scr_msg(s, set)
    489 	char *s;
    490 	int set;
    491 {
    492 
    493 	if (set || CEstr == NULL) {
    494 		int l = strlen(s);
    495 
    496 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
    497 		if (set)
    498 			putstr(s);
    499 		else
    500 			while (--l >= 0)
    501 				(void) putchar(' ');
    502 	} else {
    503 		moveto(Rows - 2, 0);
    504 		putpad(CEstr);
    505 	}
    506 }
    507