1 /* $NetBSD: screen.c,v 1.34 2021/05/02 12:50:46 rillig 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
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 * Routine used by tputs().
72 */
73 int
put(int c)74 put(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
87 static void
moveto(int r,int c)88 moveto(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
97 static void
setcolor(int c)98 setcolor(int c)
99 {
100 char *buf;
101 char monochrome[] = "\033[0m";
102 if (nocolor == 1)
103 return;
104 if (set_a_foreground == NULL)
105 return;
106
107 if (c == 0 || c == 7)
108 buf = monochrome;
109 else
110 buf = tiparm(set_a_foreground, c);
111 if (buf != NULL)
112 putpad(buf);
113 }
114
115 /*
116 * Set up from termcap.
117 */
118 void
scr_init(void)119 scr_init(void)
120 {
121
122 setupterm(NULL, 0, NULL);
123 if (clear_screen == NULL)
124 stop("cannot clear screen");
125 if (cursor_address == NULL || cursor_up == NULL)
126 stop("cannot do random cursor positioning");
127 }
128
129 /* this foolery is needed to modify tty state `atomically' */
130 static jmp_buf scr_onstop;
131
132 static void
stopset(int sig)133 stopset(int sig)
134 {
135 sigset_t set;
136
137 (void) signal(sig, SIG_DFL);
138 (void) kill(getpid(), sig);
139 sigemptyset(&set);
140 sigaddset(&set, sig);
141 (void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
142 longjmp(scr_onstop, 1);
143 }
144
145 static void
scr_stop(int sig)146 scr_stop(int sig)
147 {
148 sigset_t set;
149
150 scr_end();
151 (void) kill(getpid(), sig);
152 sigemptyset(&set);
153 sigaddset(&set, sig);
154 (void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
155 scr_set();
156 scr_msg(key_msg, 1);
157 }
158
159 /*
160 * Set up screen mode.
161 */
162 void
scr_set(void)163 scr_set(void)
164 {
165 struct winsize ws;
166 struct termios newtt;
167 sigset_t nsigset, osigset;
168 void (*ttou)(int);
169
170 sigemptyset(&nsigset);
171 sigaddset(&nsigset, SIGTSTP);
172 sigaddset(&nsigset, SIGTTOU);
173 (void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
174 if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
175 (void) signal(SIGTSTP, SIG_IGN);
176 if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
177 (void) signal(SIGTTOU, SIG_IGN);
178 /*
179 * At last, we are ready to modify the tty state. If
180 * we stop while at it, stopset() above will longjmp back
181 * to the setjmp here and we will start over.
182 */
183 (void) setjmp(scr_onstop);
184 (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
185 Rows = 0, Cols = 0;
186 if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
187 Rows = ws.ws_row;
188 Cols = ws.ws_col;
189 }
190 if (Rows == 0)
191 Rows = lines;
192 if (Cols == 0)
193 Cols = columns;
194 if (Rows < MINROWS || Cols < MINCOLS) {
195 (void) fprintf(stderr,
196 "the screen is too small: must be at least %dx%d, ",
197 MINCOLS, MINROWS);
198 stop(""); /* stop() supplies \n */
199 }
200 Offset = (Rows - D_LAST + D_FIRST - 2) / 2;
201 if (tcgetattr(0, &oldtt) < 0)
202 stop("tcgetattr() fails");
203 newtt = oldtt;
204 newtt.c_lflag &= ~(ICANON|ECHO);
205 newtt.c_oflag &= ~OXTABS;
206 if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
207 stop("tcsetattr() fails");
208 ospeed = cfgetospeed(&newtt);
209 (void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
210
211 /*
212 * We made it. We are now in screen mode, modulo TIstr
213 * (which we will fix immediately).
214 */
215 const char *tstr;
216 if ((tstr = enter_ca_mode) != NULL)
217 putstr(tstr);
218 if ((tstr = cursor_invisible) != NULL)
219 putstr(tstr);
220 if (tstp != SIG_IGN)
221 (void) signal(SIGTSTP, scr_stop);
222 if (ttou != SIG_IGN)
223 (void) signal(SIGTTOU, ttou);
224
225 isset = 1;
226 (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
227 scr_clear();
228 }
229
230 /*
231 * End screen mode.
232 */
233 void
scr_end(void)234 scr_end(void)
235 {
236 sigset_t nsigset, osigset;
237
238 sigemptyset(&nsigset);
239 sigaddset(&nsigset, SIGTSTP);
240 sigaddset(&nsigset, SIGTTOU);
241 (void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
242 /* move cursor to last line */
243 const char *tstr;
244 if ((tstr = cursor_to_ll) != NULL)
245 putstr(tstr);
246 else
247 moveto(Rows - 1, 0);
248 /* exit screen mode */
249 if ((tstr = exit_ca_mode) != NULL)
250 putstr(tstr);
251 if ((tstr = cursor_normal) != NULL)
252 putstr(tstr);
253 (void) fflush(stdout);
254 (void) tcsetattr(0, TCSADRAIN, &oldtt);
255 isset = 0;
256 /* restore signals */
257 (void) signal(SIGTSTP, tstp);
258 (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
259 }
260
261 void
stop(const char * why)262 stop(const char *why)
263 {
264
265 if (isset)
266 scr_end();
267 (void) fprintf(stderr, "aborting: %s\n", why);
268 exit(1);
269 }
270
271 /*
272 * Clear the screen, forgetting the current contents in the process.
273 */
274 void
scr_clear(void)275 scr_clear(void)
276 {
277
278 putpad(clear_screen);
279 curscore = -1;
280 memset((char *)curscreen, 0, sizeof(curscreen));
281 }
282
283 #if vax && !__GNUC__
284 typedef int regcell; /* pcc is bad at `register char', etc */
285 #else
286 typedef cell regcell;
287 #endif
288
289 /*
290 * Update the screen.
291 */
292 void
scr_update(void)293 scr_update(void)
294 {
295 cell *bp, *sp;
296 regcell so, cur_so = 0;
297 int i, ccol, j;
298 sigset_t nsigset, osigset;
299 static const struct shape *lastshape;
300
301 sigemptyset(&nsigset);
302 sigaddset(&nsigset, SIGTSTP);
303 (void) sigprocmask(SIG_BLOCK, &nsigset, &osigset);
304
305 /* always leave cursor after last displayed point */
306 curscreen[D_LAST * B_COLS - 1] = -1;
307
308 if (score != curscore) {
309 if (cursor_home)
310 putpad(cursor_home);
311 else
312 moveto(0, 0);
313 setcolor(0);
314 (void) printf("Score: %d", score);
315 curscore = score;
316 }
317
318 /* draw preview of nextpattern */
319 if (showpreview && (nextshape != lastshape)) {
320 static int r=5, c=2;
321 int tr, tc, t;
322
323 lastshape = nextshape;
324
325 /* clean */
326 putpad(exit_standout_mode);
327 moveto(r-1, c-1); putstr(" ");
328 moveto(r, c-1); putstr(" ");
329 moveto(r+1, c-1); putstr(" ");
330 moveto(r+2, c-1); putstr(" ");
331
332 moveto(r-3, c-2);
333 putstr("Next shape:");
334
335 /* draw */
336 setcolor(nextshape->color);
337 putpad(enter_standout_mode);
338 moveto(r, 2*c);
339 putstr(" ");
340 for(i=0; i<3; i++) {
341 t = c + r*B_COLS;
342 t += nextshape->off[i];
343
344 tr = t / B_COLS;
345 tc = t % B_COLS;
346
347 moveto(tr, 2*tc);
348 putstr(" ");
349 }
350 putpad(exit_standout_mode);
351 }
352
353 bp = &board[D_FIRST * B_COLS];
354 sp = &curscreen[D_FIRST * B_COLS];
355 for (j = D_FIRST; j < D_LAST; j++) {
356 ccol = -1;
357 for (i = 0; i < B_COLS; bp++, sp++, i++) {
358 if (*sp == (so = *bp))
359 continue;
360 *sp = so;
361 if (i != ccol) {
362 if (cur_so && move_standout_mode) {
363 putpad(exit_standout_mode);
364 cur_so = 0;
365 }
366 moveto(RTOD(j + Offset), CTOD(i));
367 }
368 if (enter_standout_mode) {
369 if (so != cur_so) {
370 setcolor(so);
371 putpad(so ?
372 enter_standout_mode :
373 exit_standout_mode);
374 cur_so = so;
375 }
376 #ifdef DEBUG
377 char buf[3];
378 snprintf(buf, sizeof(buf), "%d%d", so, so);
379 putstr(buf);
380 #else
381 putstr(" ");
382 #endif
383 } else
384 putstr(so ? "XX" : " ");
385 ccol = i + 1;
386 /*
387 * Look ahead a bit, to avoid extra motion if
388 * we will be redrawing the cell after the next.
389 * Motion probably takes four or more characters,
390 * so we save even if we rewrite two cells
391 * `unnecessarily'. Skip it all, though, if
392 * the next cell is a different color.
393 */
394 #define STOP (B_COLS - 3)
395 if (i > STOP || sp[1] != bp[1] || so != bp[1])
396 continue;
397 if (sp[2] != bp[2])
398 sp[1] = -1;
399 else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
400 sp[2] = -1;
401 sp[1] = -1;
402 }
403 }
404 }
405 if (cur_so)
406 putpad(exit_standout_mode);
407 (void) fflush(stdout);
408 (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
409 }
410
411 /*
412 * Write a message (set!=0), or clear the same message (set==0).
413 * (We need its length in case we have to overwrite with blanks.)
414 */
415 void
scr_msg(char * s,int set)416 scr_msg(char *s, int set)
417 {
418
419 if (set || clr_eol == NULL) {
420 int l = strlen(s);
421
422 moveto(Rows - 2, ((Cols - l) >> 1) - 1);
423 if (set)
424 putstr(s);
425 else
426 while (--l >= 0)
427 (void) putchar(' ');
428 } else {
429 moveto(Rows - 2, 0);
430 putpad(clr_eol);
431 }
432 }
433