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screen.c revision 1.25 
      1 /*	$NetBSD: screen.c,v 1.25 2009/12/19 19:27:53 ahoka 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 extern 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 	*VIstr,			/* make cursor invisible */
     89 	*VEstr;			/* make cursor appear normal */
     90 char
     91 	*SEstr,			/* end standout mode */
     92 	*SOstr;			/* begin standout mode */
     93 static int
     94 	COnum,			/* co# value */
     95 	LInum,			/* li# value */
     96 	MSflag;			/* can move in standout mode */
     97 
     98 
     99 static struct tcsinfo {	/* termcap string info; some abbrevs above */
    100 	char tcname[3];
    101 	char **tcaddr;
    102 } tcstrings[] = {
    103 	{"bc", &bcstr},
    104 	{"ce", &CEstr},
    105 	{"cl", &CLstr},
    106 	{"cm", &CMstr},
    107 #ifdef unneeded
    108 	{"cr", &CRstr},
    109 #endif
    110 	{"le", &BC},		/* move cursor left one space */
    111 	{"pc", &pcstr},
    112 	{"se", &SEstr},
    113 	{"so", &SOstr},
    114 	{"te", &TEstr},
    115 	{"ti", &TIstr},
    116 	{"vi", &VIstr},
    117 	{"ve", &VEstr},
    118 	{"up", &UP},		/* cursor up */
    119 	{ {0}, NULL}
    120 };
    121 
    122 /* This is where we will actually stuff the information */
    123 
    124 static struct tinfo *info;
    125 
    126 /*
    127  * Routine used by tputs().
    128  */
    129 int
    130 put(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 static 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(void)
    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 	static char backspace[] = "\b";
    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 	{
    187 		struct tcsinfo *p;
    188 
    189 		for (p = tcstrings; p->tcaddr; p++)
    190 			*p->tcaddr = t_agetstr(info, p->tcname);
    191 	}
    192 	{
    193 		struct tcninfo *p;
    194 
    195 		for (p = tcflags; p->tcaddr; p++)
    196 			*p->tcaddr = t_getflag(info, p->tcname);
    197 		for (p = tcnums; p->tcaddr; p++)
    198 			*p->tcaddr = t_getnum(info, p->tcname);
    199 	}
    200 	if (bsflag)
    201 		BC = backspace;
    202 	else if (BC == NULL && bcstr != NULL)
    203 		BC = bcstr;
    204 	if (CLstr == NULL)
    205 		stop("cannot clear screen");
    206 	if (CMstr == NULL || UP == NULL || BC == NULL)
    207 		stop("cannot do random cursor positioning via tgoto()");
    208 	PC = pcstr ? *pcstr : 0;
    209 	if (sgnum >= 0 || xsflag)
    210 		SOstr = SEstr = NULL;
    211 #ifdef unneeded
    212 	if (ncflag)
    213 		CRstr = NULL;
    214 	else if (CRstr == NULL)
    215 		CRstr = "\r";
    216 #endif
    217 }
    218 
    219 /* this foolery is needed to modify tty state `atomically' */
    220 static jmp_buf scr_onstop;
    221 
    222 static void
    223 stopset(int sig)
    224 {
    225 	sigset_t set;
    226 
    227 	(void) signal(sig, SIG_DFL);
    228 	(void) kill(getpid(), sig);
    229 	sigemptyset(&set);
    230 	sigaddset(&set, sig);
    231 	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
    232 	longjmp(scr_onstop, 1);
    233 }
    234 
    235 static void
    236 scr_stop(int sig)
    237 {
    238 	sigset_t set;
    239 
    240 	scr_end();
    241 	(void) kill(getpid(), sig);
    242 	sigemptyset(&set);
    243 	sigaddset(&set, sig);
    244 	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
    245 	scr_set();
    246 	scr_msg(key_msg, 1);
    247 }
    248 
    249 /*
    250  * Set up screen mode.
    251  */
    252 void
    253 scr_set(void)
    254 {
    255 	struct winsize ws;
    256 	struct termios newtt;
    257 	sigset_t nsigset, osigset;
    258 	void (*ttou)(int);
    259 
    260 	sigemptyset(&nsigset);
    261 	sigaddset(&nsigset, SIGTSTP);
    262 	sigaddset(&nsigset, SIGTTOU);
    263 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
    264 	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
    265 		(void) signal(SIGTSTP, SIG_IGN);
    266 	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
    267 		(void) signal(SIGTTOU, SIG_IGN);
    268 	/*
    269 	 * At last, we are ready to modify the tty state.  If
    270 	 * we stop while at it, stopset() above will longjmp back
    271 	 * to the setjmp here and we will start over.
    272 	 */
    273 	(void) setjmp(scr_onstop);
    274 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    275 	Rows = 0, Cols = 0;
    276 	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
    277 		Rows = ws.ws_row;
    278 		Cols = ws.ws_col;
    279 	}
    280 	if (Rows == 0)
    281 		Rows = LInum;
    282 	if (Cols == 0)
    283 	Cols = COnum;
    284 	if (Rows < MINROWS || Cols < MINCOLS) {
    285 		(void) fprintf(stderr,
    286 		    "the screen is too small: must be at least %dx%d, ",
    287 		    MINCOLS, MINROWS);
    288 		stop("");	/* stop() supplies \n */
    289 	}
    290 	if (tcgetattr(0, &oldtt) < 0)
    291 		stop("tcgetattr() fails");
    292 	newtt = oldtt;
    293 	newtt.c_lflag &= ~(ICANON|ECHO);
    294 	newtt.c_oflag &= ~OXTABS;
    295 	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
    296 		stop("tcsetattr() fails");
    297 	ospeed = cfgetospeed(&newtt);
    298 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
    299 
    300 	/*
    301 	 * We made it.  We are now in screen mode, modulo TIstr
    302 	 * (which we will fix immediately).
    303 	 */
    304 	if (TIstr)
    305 		putstr(TIstr);	/* termcap(5) says this is not padded */
    306 	if (VIstr)
    307 		putstr(VIstr);	/* termcap(5) says this is not padded */
    308 	if (tstp != SIG_IGN)
    309 		(void) signal(SIGTSTP, scr_stop);
    310 	if (ttou != SIG_IGN)
    311 		(void) signal(SIGTTOU, ttou);
    312 
    313 	isset = 1;
    314 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    315 	scr_clear();
    316 }
    317 
    318 /*
    319  * End screen mode.
    320  */
    321 void
    322 scr_end(void)
    323 {
    324 	sigset_t nsigset, osigset;
    325 
    326 	sigemptyset(&nsigset);
    327 	sigaddset(&nsigset, SIGTSTP);
    328 	sigaddset(&nsigset, SIGTTOU);
    329 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
    330 	/* move cursor to last line */
    331 	if (LLstr)
    332 		putstr(LLstr);	/* termcap(5) says this is not padded */
    333 	else
    334 		moveto(Rows - 1, 0);
    335 	/* exit screen mode */
    336 	if (TEstr)
    337 		putstr(TEstr);	/* termcap(5) says this is not padded */
    338 	if (VEstr)
    339 		putstr(VEstr);	/* 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(const char *why)
    350 {
    351 
    352 	if (isset)
    353 		scr_end();
    354 	(void) fprintf(stderr, "aborting: %s\n", why);
    355 	exit(1);
    356 }
    357 
    358 /*
    359  * Clear the screen, forgetting the current contents in the process.
    360  */
    361 void
    362 scr_clear(void)
    363 {
    364 
    365 	putpad(CLstr);
    366 	curscore = -1;
    367 	memset((char *)curscreen, 0, sizeof(curscreen));
    368 }
    369 
    370 #if vax && !__GNUC__
    371 typedef int regcell;	/* pcc is bad at `register char', etc */
    372 #else
    373 typedef cell regcell;
    374 #endif
    375 
    376 /*
    377  * Update the screen.
    378  */
    379 void
    380 scr_update(void)
    381 {
    382 	cell *bp, *sp;
    383 	regcell so, cur_so = 0;
    384 	int i, ccol, j;
    385 	sigset_t nsigset, osigset;
    386 	static const struct shape *lastshape;
    387 
    388 	sigemptyset(&nsigset);
    389 	sigaddset(&nsigset, SIGTSTP);
    390 	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
    391 
    392 	/* always leave cursor after last displayed point */
    393 	curscreen[D_LAST * B_COLS - 1] = -1;
    394 
    395 	if (score != curscore) {
    396 		if (HOstr)
    397 			putpad(HOstr);
    398 		else
    399 			moveto(0, 0);
    400 		(void) printf("Score: %d", score);
    401 		curscore = score;
    402 	}
    403 
    404 	/* draw preview of nextpattern */
    405 	if (showpreview && (nextshape != lastshape)) {
    406 		static int r=5, c=2;
    407 		int tr, tc, t;
    408 
    409 		lastshape = nextshape;
    410 
    411 		/* clean */
    412 		putpad(SEstr);
    413 		moveto(r-1, c-1); putstr("          ");
    414 		moveto(r,   c-1); putstr("          ");
    415 		moveto(r+1, c-1); putstr("          ");
    416 		moveto(r+2, c-1); putstr("          ");
    417 
    418 		moveto(r-3, c-2);
    419 		putstr("Next shape:");
    420 
    421 		/* draw */
    422 		putpad(SOstr);
    423 		moveto(r, 2*c);
    424 		putstr("  ");
    425 		for(i=0; i<3; i++) {
    426 			t = c + r*B_COLS;
    427 			t += nextshape->off[i];
    428 
    429 			tr = t / B_COLS;
    430 			tc = t % B_COLS;
    431 
    432 			moveto(tr, 2*tc);
    433 			putstr("  ");
    434 		}
    435 		putpad(SEstr);
    436 	}
    437 
    438 	bp = &board[D_FIRST * B_COLS];
    439 	sp = &curscreen[D_FIRST * B_COLS];
    440 	for (j = D_FIRST; j < D_LAST; j++) {
    441 		ccol = -1;
    442 		for (i = 0; i < B_COLS; bp++, sp++, i++) {
    443 			if (*sp == (so = *bp))
    444 				continue;
    445 			*sp = so;
    446 			if (i != ccol) {
    447 				if (cur_so && MSflag) {
    448 					putpad(SEstr);
    449 					cur_so = 0;
    450 				}
    451 				moveto(RTOD(j), CTOD(i));
    452 			}
    453 			if (SOstr) {
    454 				if (so != cur_so) {
    455 					putpad(so ? SOstr : SEstr);
    456 					cur_so = so;
    457 				}
    458 				putstr("  ");
    459 			} else
    460 				putstr(so ? "XX" : "  ");
    461 			ccol = i + 1;
    462 			/*
    463 			 * Look ahead a bit, to avoid extra motion if
    464 			 * we will be redrawing the cell after the next.
    465 			 * Motion probably takes four or more characters,
    466 			 * so we save even if we rewrite two cells
    467 			 * `unnecessarily'.  Skip it all, though, if
    468 			 * the next cell is a different color.
    469 			 */
    470 #define	STOP (B_COLS - 3)
    471 			if (i > STOP || sp[1] != bp[1] || so != bp[1])
    472 				continue;
    473 			if (sp[2] != bp[2])
    474 				sp[1] = -1;
    475 			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
    476 				sp[2] = -1;
    477 				sp[1] = -1;
    478 			}
    479 		}
    480 	}
    481 	if (cur_so)
    482 		putpad(SEstr);
    483 	(void) fflush(stdout);
    484 	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
    485 }
    486 
    487 /*
    488  * Write a message (set!=0), or clear the same message (set==0).
    489  * (We need its length in case we have to overwrite with blanks.)
    490  */
    491 void
    492 scr_msg(char *s, int set)
    493 {
    494 
    495 	if (set || CEstr == NULL) {
    496 		int l = strlen(s);
    497 
    498 		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
    499 		if (set)
    500 			putstr(s);
    501 		else
    502 			while (--l >= 0)
    503 				(void) putchar(' ');
    504 	} else {
    505 		moveto(Rows - 2, 0);
    506 		putpad(CEstr);
    507 	}
    508 }
    509