screen.c revision 1.22 
1/*	$NetBSD: screen.c,v 1.22 2008/01/28 01:38:59 dholland 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 */
73short	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 */
88char
89	*SEstr,			/* end standout mode */
90	*SOstr;			/* begin standout mode */
91static int
92	COnum,			/* co# value */
93	LInum,			/* li# value */
94	MSflag;			/* can move in standout mode */
95
96
97struct 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
120static struct tinfo *info;
121
122/*
123 * Routine used by tputs().
124 */
125int
126put(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
140void
141moveto(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 */
152void
153scr_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	static char backspace[] = "\b";
178
179	if ((term = getenv("TERM")) == NULL)
180		stop("you must set the TERM environment variable");
181	if (t_getent(&info, term) <= 0)
182		stop("cannot find your termcap");
183	{
184		struct tcsinfo *p;
185
186		for (p = tcstrings; p->tcaddr; p++)
187			*p->tcaddr = t_agetstr(info, p->tcname);
188	}
189	{
190		struct tcninfo *p;
191
192		for (p = tcflags; p->tcaddr; p++)
193			*p->tcaddr = t_getflag(info, p->tcname);
194		for (p = tcnums; p->tcaddr; p++)
195			*p->tcaddr = t_getnum(info, p->tcname);
196	}
197	if (bsflag)
198		BC = backspace;
199	else if (BC == NULL && bcstr != NULL)
200		BC = bcstr;
201	if (CLstr == NULL)
202		stop("cannot clear screen");
203	if (CMstr == NULL || UP == NULL || BC == NULL)
204		stop("cannot do random cursor positioning via tgoto()");
205	PC = pcstr ? *pcstr : 0;
206	if (sgnum >= 0 || xsflag)
207		SOstr = SEstr = NULL;
208#ifdef unneeded
209	if (ncflag)
210		CRstr = NULL;
211	else if (CRstr == NULL)
212		CRstr = "\r";
213#endif
214}
215
216/* this foolery is needed to modify tty state `atomically' */
217static jmp_buf scr_onstop;
218
219static void
220stopset(sig)
221	int sig;
222{
223	sigset_t set;
224
225	(void) signal(sig, SIG_DFL);
226	(void) kill(getpid(), sig);
227	sigemptyset(&set);
228	sigaddset(&set, sig);
229	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
230	longjmp(scr_onstop, 1);
231}
232
233static void
234scr_stop(sig)
235	int sig;
236{
237	sigset_t set;
238
239	scr_end();
240	(void) kill(getpid(), sig);
241	sigemptyset(&set);
242	sigaddset(&set, sig);
243	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
244	scr_set();
245	scr_msg(key_msg, 1);
246}
247
248/*
249 * Set up screen mode.
250 */
251void
252scr_set()
253{
254	struct winsize ws;
255	struct termios newtt;
256	sigset_t nsigset, osigset;
257	void (*ttou)(int);
258
259	sigemptyset(&nsigset);
260	sigaddset(&nsigset, SIGTSTP);
261	sigaddset(&nsigset, SIGTTOU);
262	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
263	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
264		(void) signal(SIGTSTP, SIG_IGN);
265	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
266		(void) signal(SIGTTOU, SIG_IGN);
267	/*
268	 * At last, we are ready to modify the tty state.  If
269	 * we stop while at it, stopset() above will longjmp back
270	 * to the setjmp here and we will start over.
271	 */
272	(void) setjmp(scr_onstop);
273	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
274	Rows = 0, Cols = 0;
275	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
276		Rows = ws.ws_row;
277		Cols = ws.ws_col;
278	}
279	if (Rows == 0)
280		Rows = LInum;
281	if (Cols == 0)
282	Cols = COnum;
283	if (Rows < MINROWS || Cols < MINCOLS) {
284		(void) fprintf(stderr,
285		    "the screen is too small: must be at least %dx%d, ",
286		    MINCOLS, MINROWS);
287		stop("");	/* stop() supplies \n */
288	}
289	if (tcgetattr(0, &oldtt) < 0)
290		stop("tcgetattr() fails");
291	newtt = oldtt;
292	newtt.c_lflag &= ~(ICANON|ECHO);
293	newtt.c_oflag &= ~OXTABS;
294	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
295		stop("tcsetattr() fails");
296	ospeed = cfgetospeed(&newtt);
297	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
298
299	/*
300	 * We made it.  We are now in screen mode, modulo TIstr
301	 * (which we will fix immediately).
302	 */
303	if (TIstr)
304		putstr(TIstr);	/* termcap(5) says this is not padded */
305	if (tstp != SIG_IGN)
306		(void) signal(SIGTSTP, scr_stop);
307	if (ttou != SIG_IGN)
308		(void) signal(SIGTTOU, ttou);
309
310	isset = 1;
311	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
312	scr_clear();
313}
314
315/*
316 * End screen mode.
317 */
318void
319scr_end()
320{
321	sigset_t nsigset, osigset;
322
323	sigemptyset(&nsigset);
324	sigaddset(&nsigset, SIGTSTP);
325	sigaddset(&nsigset, SIGTTOU);
326	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
327	/* move cursor to last line */
328	if (LLstr)
329		putstr(LLstr);	/* termcap(5) says this is not padded */
330	else
331		moveto(Rows - 1, 0);
332	/* exit screen mode */
333	if (TEstr)
334		putstr(TEstr);	/* termcap(5) says this is not padded */
335	(void) fflush(stdout);
336	(void) tcsetattr(0, TCSADRAIN, &oldtt);
337	isset = 0;
338	/* restore signals */
339	(void) signal(SIGTSTP, tstp);
340	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
341}
342
343void
344stop(why)
345	const char *why;
346{
347
348	if (isset)
349		scr_end();
350	(void) fprintf(stderr, "aborting: %s\n", why);
351	exit(1);
352}
353
354/*
355 * Clear the screen, forgetting the current contents in the process.
356 */
357void
358scr_clear()
359{
360
361	putpad(CLstr);
362	curscore = -1;
363	memset((char *)curscreen, 0, sizeof(curscreen));
364}
365
366#if vax && !__GNUC__
367typedef int regcell;	/* pcc is bad at `register char', etc */
368#else
369typedef cell regcell;
370#endif
371
372/*
373 * Update the screen.
374 */
375void
376scr_update()
377{
378	cell *bp, *sp;
379	regcell so, cur_so = 0;
380	int i, ccol, j;
381	sigset_t nsigset, osigset;
382	static const struct shape *lastshape;
383
384	sigemptyset(&nsigset);
385	sigaddset(&nsigset, SIGTSTP);
386	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
387
388	/* always leave cursor after last displayed point */
389	curscreen[D_LAST * B_COLS - 1] = -1;
390
391	if (score != curscore) {
392		if (HOstr)
393			putpad(HOstr);
394		else
395			moveto(0, 0);
396		(void) printf("Score: %d", score);
397		curscore = score;
398	}
399
400	/* draw preview of nextpattern */
401	if (showpreview && (nextshape != lastshape)) {
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 */
487void
488scr_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