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
60static cell curscreen[B_SIZE];	/* 1 => standout (or otherwise marked) */
61static int curscore;
62static int isset;		/* true => terminal is in game mode */
63static struct termios oldtt;
64static void (*tstp)(int);
65
66static	void	scr_stop(int);
67static	void	stopset(int) __dead;
68
69
70/*
71 * Capabilities from TERMCAP.
72 */
73extern short ospeed;
74
75static 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 */
90char
91	*SEstr,			/* end standout mode */
92	*SOstr;			/* begin standout mode */
93static int
94	COnum,			/* co# value */
95	LInum,			/* li# value */
96	MSflag;			/* can move in standout mode */
97
98
99static 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
124static struct tinfo *info;
125
126/*
127 * Routine used by tputs().
128 */
129int
130put(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
143static void
144moveto(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 */
155void
156scr_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' */
220static jmp_buf scr_onstop;
221
222static void
223stopset(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
235static void
236scr_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 */
252void
253scr_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 */
321void
322scr_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
348void
349stop(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 */
361void
362scr_clear(void)
363{
364
365	putpad(CLstr);
366	curscore = -1;
367	memset((char *)curscreen, 0, sizeof(curscreen));
368}
369
370#if vax && !__GNUC__
371typedef int regcell;	/* pcc is bad at `register char', etc */
372#else
373typedef cell regcell;
374#endif
375
376/*
377 * Update the screen.
378 */
379void
380scr_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 */
491void
492scr_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