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
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
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' */
216static jmp_buf scr_onstop;
217
218static void
219stopset(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
232static void
233scr_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 */
250void
251scr_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 */
317void
318scr_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
342void
343stop(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 */
356void
357scr_clear()
358{
359
360	putpad(CLstr);
361	curscore = -1;
362	memset((char *)curscreen, 0, sizeof(curscreen));
363}
364
365#if vax && !__GNUC__
366typedef int regcell;	/* pcc is bad at `register char', etc */
367#else
368typedef cell regcell;
369#endif
370
371/*
372 * Update the screen.
373 */
374void
375scr_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 */
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