screen.c revision 1.28 
1/*	$NetBSD: screen.c,v 1.28 2014/06/11 16:47:39 christos 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 <term.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 * Routine used by tputs().
72 */
73int
74put(int c)
75{
76
77	return (putchar(c));
78}
79
80/*
81 * putstr() is for unpadded strings (either as in termcap(5) or
82 * simply literal strings); putpad() is for padded strings with
83 * count=1.  (See screen.h for putpad().)
84 */
85#define	putstr(s)	(void)fputs(s, stdout)
86
87static void
88moveto(int r, int c)
89{
90	char *buf;
91
92	buf = tiparm(cursor_address, r, c);
93	if (buf != NULL)
94		putpad(buf);
95}
96
97static void
98setcolor(int c)
99{
100	char *buf;
101	if (set_a_foreground == NULL)
102		return;
103
104	buf = tiparm(set_a_foreground, c == 7 ? 0 : c);
105	if (buf != NULL)
106		putpad(buf);
107}
108
109/*
110 * Set up from termcap.
111 */
112void
113scr_init(void)
114{
115
116	setupterm(NULL, 0, NULL);
117	if (clear_screen == NULL)
118		stop("cannot clear screen");
119	if (cursor_address == NULL || cursor_up == NULL)
120		stop("cannot do random cursor positioning");
121}
122
123/* this foolery is needed to modify tty state `atomically' */
124static jmp_buf scr_onstop;
125
126static void
127stopset(int sig)
128{
129	sigset_t set;
130
131	(void) signal(sig, SIG_DFL);
132	(void) kill(getpid(), sig);
133	sigemptyset(&set);
134	sigaddset(&set, sig);
135	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
136	longjmp(scr_onstop, 1);
137}
138
139static void
140scr_stop(int sig)
141{
142	sigset_t set;
143
144	scr_end();
145	(void) kill(getpid(), sig);
146	sigemptyset(&set);
147	sigaddset(&set, sig);
148	(void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
149	scr_set();
150	scr_msg(key_msg, 1);
151}
152
153/*
154 * Set up screen mode.
155 */
156void
157scr_set(void)
158{
159	struct winsize ws;
160	struct termios newtt;
161	sigset_t nsigset, osigset;
162	void (*ttou)(int);
163
164	sigemptyset(&nsigset);
165	sigaddset(&nsigset, SIGTSTP);
166	sigaddset(&nsigset, SIGTTOU);
167	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
168	if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
169		(void) signal(SIGTSTP, SIG_IGN);
170	if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
171		(void) signal(SIGTTOU, SIG_IGN);
172	/*
173	 * At last, we are ready to modify the tty state.  If
174	 * we stop while at it, stopset() above will longjmp back
175	 * to the setjmp here and we will start over.
176	 */
177	(void) setjmp(scr_onstop);
178	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
179	Rows = 0, Cols = 0;
180	if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
181		Rows = ws.ws_row;
182		Cols = ws.ws_col;
183	}
184	if (Rows == 0)
185		Rows = lines;
186	if (Cols == 0)
187	    Cols = columns;
188	if (Rows < MINROWS || Cols < MINCOLS) {
189		(void) fprintf(stderr,
190		    "the screen is too small: must be at least %dx%d, ",
191		    MINCOLS, MINROWS);
192		stop("");	/* stop() supplies \n */
193	}
194	if (tcgetattr(0, &oldtt) < 0)
195		stop("tcgetattr() fails");
196	newtt = oldtt;
197	newtt.c_lflag &= ~(ICANON|ECHO);
198	newtt.c_oflag &= ~OXTABS;
199	if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
200		stop("tcsetattr() fails");
201	ospeed = cfgetospeed(&newtt);
202	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
203
204	/*
205	 * We made it.  We are now in screen mode, modulo TIstr
206	 * (which we will fix immediately).
207	 */
208	if (enter_ca_mode)
209		putstr(enter_ca_mode);
210	if (cursor_invisible)
211		putstr(cursor_invisible);
212	if (tstp != SIG_IGN)
213		(void) signal(SIGTSTP, scr_stop);
214	if (ttou != SIG_IGN)
215		(void) signal(SIGTTOU, ttou);
216
217	isset = 1;
218	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
219	scr_clear();
220}
221
222/*
223 * End screen mode.
224 */
225void
226scr_end(void)
227{
228	sigset_t nsigset, osigset;
229
230	sigemptyset(&nsigset);
231	sigaddset(&nsigset, SIGTSTP);
232	sigaddset(&nsigset, SIGTTOU);
233	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
234	/* move cursor to last line */
235	if (cursor_to_ll)
236		putstr(cursor_to_ll);
237	else
238		moveto(Rows - 1, 0);
239	/* exit screen mode */
240	if (exit_ca_mode)
241		putstr(exit_ca_mode);
242	if (cursor_normal)
243		putstr(cursor_normal);
244	(void) fflush(stdout);
245	(void) tcsetattr(0, TCSADRAIN, &oldtt);
246	isset = 0;
247	/* restore signals */
248	(void) signal(SIGTSTP, tstp);
249	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
250}
251
252void
253stop(const char *why)
254{
255
256	if (isset)
257		scr_end();
258	(void) fprintf(stderr, "aborting: %s\n", why);
259	exit(1);
260}
261
262/*
263 * Clear the screen, forgetting the current contents in the process.
264 */
265void
266scr_clear(void)
267{
268
269	putpad(clear_screen);
270	curscore = -1;
271	memset((char *)curscreen, 0, sizeof(curscreen));
272}
273
274#if vax && !__GNUC__
275typedef int regcell;	/* pcc is bad at `register char', etc */
276#else
277typedef cell regcell;
278#endif
279
280/*
281 * Update the screen.
282 */
283void
284scr_update(void)
285{
286	cell *bp, *sp;
287	regcell so, cur_so = 0;
288	int i, ccol, j;
289	sigset_t nsigset, osigset;
290	static const struct shape *lastshape;
291
292	sigemptyset(&nsigset);
293	sigaddset(&nsigset, SIGTSTP);
294	(void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
295
296	/* always leave cursor after last displayed point */
297	curscreen[D_LAST * B_COLS - 1] = -1;
298
299	if (score != curscore) {
300		if (cursor_home)
301			putpad(cursor_home);
302		else
303			moveto(0, 0);
304		(void) printf("Score: %d", score);
305		curscore = score;
306	}
307
308	/* draw preview of nextpattern */
309	if (showpreview && (nextshape != lastshape)) {
310		static int r=5, c=2;
311		int tr, tc, t;
312
313		lastshape = nextshape;
314
315		/* clean */
316		putpad(exit_standout_mode);
317		moveto(r-1, c-1); putstr("          ");
318		moveto(r,   c-1); putstr("          ");
319		moveto(r+1, c-1); putstr("          ");
320		moveto(r+2, c-1); putstr("          ");
321
322		moveto(r-3, c-2);
323		putstr("Next shape:");
324
325		/* draw */
326		putpad(enter_standout_mode);
327		setcolor(nextshape->color);
328		moveto(r, 2*c);
329		putstr("  ");
330		for(i=0; i<3; i++) {
331			t = c + r*B_COLS;
332			t += nextshape->off[i];
333
334			tr = t / B_COLS;
335			tc = t % B_COLS;
336
337			moveto(tr, 2*tc);
338			putstr("  ");
339		}
340		putpad(exit_standout_mode);
341	}
342
343	bp = &board[D_FIRST * B_COLS];
344	sp = &curscreen[D_FIRST * B_COLS];
345	for (j = D_FIRST; j < D_LAST; j++) {
346		ccol = -1;
347		for (i = 0; i < B_COLS; bp++, sp++, i++) {
348			if (*sp == (so = *bp))
349				continue;
350			*sp = so;
351			if (i != ccol) {
352				if (cur_so && move_standout_mode) {
353					putpad(exit_standout_mode);
354					cur_so = 0;
355				}
356				moveto(RTOD(j), CTOD(i));
357			}
358			if (enter_standout_mode) {
359				if (so != cur_so) {
360					putpad(so ?
361					    enter_standout_mode :
362					    exit_standout_mode);
363					cur_so = so;
364				}
365				setcolor(so);
366#ifdef DEBUG
367				char buf[3];
368				snprintf(buf, sizeof(buf), "%d%d", so, so);
369				putstr(buf);
370#else
371				putstr("  ");
372#endif
373			} else
374				putstr(so ? "XX" : "  ");
375			ccol = i + 1;
376			/*
377			 * Look ahead a bit, to avoid extra motion if
378			 * we will be redrawing the cell after the next.
379			 * Motion probably takes four or more characters,
380			 * so we save even if we rewrite two cells
381			 * `unnecessarily'.  Skip it all, though, if
382			 * the next cell is a different color.
383			 */
384#define	STOP (B_COLS - 3)
385			if (i > STOP || sp[1] != bp[1] || so != bp[1])
386				continue;
387			if (sp[2] != bp[2])
388				sp[1] = -1;
389			else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
390				sp[2] = -1;
391				sp[1] = -1;
392			}
393		}
394	}
395	if (cur_so)
396		putpad(exit_standout_mode);
397	(void) fflush(stdout);
398	(void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
399}
400
401/*
402 * Write a message (set!=0), or clear the same message (set==0).
403 * (We need its length in case we have to overwrite with blanks.)
404 */
405void
406scr_msg(char *s, int set)
407{
408
409	if (set || clr_eol == NULL) {
410		int l = strlen(s);
411
412		moveto(Rows - 2, ((Cols - l) >> 1) - 1);
413		if (set)
414			putstr(s);
415		else
416			while (--l >= 0)
417				(void) putchar(' ');
418	} else {
419		moveto(Rows - 2, 0);
420		putpad(clr_eol);
421	}
422}
423