tetris/screen.c

   1 /*      $NetBSD: screen.c,v 1.6 1997/10/14 01:14:28 lukem 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. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)screen.c    8.1 (Berkeley) 5/31/93
  39  */
  40
  41 /*
  42  * Tetris screen control.
  43  */
  44
  45 #include <sys/ioctl.h>
  46
  47 #include <setjmp.h>
  48 #include <signal.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <termcap.h>
  53 #include <termios.h>
  54 #include <unistd.h>
  55
  56 #ifndef sigmask
  57 #define sigmask(s) (1 << ((s) - 1))
  58 #endif
  59
  60 #include "screen.h"
  61 #include "tetris.h"
  62
  63 static cell curscreen[B_SIZE];  /* 1 => standout (or otherwise marked) */
  64 static int curscore;
  65 static int isset;               /* true => terminal is in game mode */
  66 static struct termios oldtt;
  67 static void (*tstp) __P((int));
  68
  69 static  void    scr_stop __P((int));
  70 static  void    stopset __P((int));
  71
  72
  73 /*
  74  * Capabilities from TERMCAP.
  75  */
  76 char    PC, *BC, *UP;           /* tgoto requires globals: ugh! */
  77 speed_t ospeed;
  78
  79 static char
  80         *bcstr,                 /* backspace char */
  81         *CEstr,                 /* clear to end of line */
  82         *CLstr,                 /* clear screen */
  83         *CMstr,                 /* cursor motion string */
  84 #ifdef unneeded
  85         *CRstr,                 /* "\r" equivalent */
  86 #endif
  87         *HOstr,                 /* cursor home */
  88         *LLstr,                 /* last line, first column */
  89         *pcstr,                 /* pad character */
  90         *TEstr,                 /* end cursor motion mode */
  91         *TIstr;                 /* begin cursor motion mode */
  92 char
  93         *SEstr,                 /* end standout mode */
  94         *SOstr;                 /* begin standout mode */
  95 static int
  96         COnum,                  /* co# value */
  97         LInum,                  /* li# value */
  98         MSflag;                 /* can move in standout mode */
  99
 100
 101 struct tcsinfo {        /* termcap string info; some abbrevs above */
 102         char tcname[3];
 103         char **tcaddr;
 104 } tcstrings[] = {
 105         {"bc", &bcstr},
 106         {"ce", &CEstr},
 107         {"cl", &CLstr},
 108         {"cm", &CMstr},
 109 #ifdef unneeded
 110         {"cr", &CRstr},
 111 #endif
 112         {"le", &BC},            /* move cursor left one space */
 113         {"pc", &pcstr},
 114         {"se", &SEstr},
 115         {"so", &SOstr},
 116         {"te", &TEstr},
 117         {"ti", &TIstr},
 118         {"up", &UP},            /* cursor up */
 119         { {0}, NULL}
 120 };
 121
 122 /* This is where we will actually stuff the information */
 123
 124 static char combuf[1024], tbuf[1024];
 125
 126
 127 /*
 128  * Routine used by tputs().
 129  */
 130 void
 131 put(c)
 132         int c;
 133 {
 134
 135         (void) putchar(c);
 136 }
 137
 138 /*
 139  * putstr() is for unpadded strings (either as in termcap(5) or
 140  * simply literal strings); putpad() is for padded strings with
 141  * count=1.  (See screen.h for putpad().)
 142  */
 143 #define putstr(s)       (void)fputs(s, stdout)
 144 #define moveto(r, c)    putpad(tgoto(CMstr, c, r))
 145
 146 /*
 147  * Set up from termcap.
 148  */
 149 void
 150 scr_init()
 151 {
 152         static int bsflag, xsflag, sgnum;
 153 #ifdef unneeded
 154         static int ncflag;
 155 #endif
 156         char *term, *fill;
 157         static struct tcninfo { /* termcap numeric and flag info */
 158                 char tcname[3];
 159                 int *tcaddr;
 160         } tcflags[] = {
 161                 {"bs", &bsflag},
 162                 {"ms", &MSflag},
 163 #ifdef unneeded
 164                 {"nc", &ncflag},
 165 #endif
 166                 {"xs", &xsflag},
 167                 { {0}, NULL}
 168         }, tcnums[] = {
 169                 {"co", &COnum},
 170                 {"li", &LInum},
 171                 {"sg", &sgnum},
 172                 { {0}, NULL}
 173         };
 174
 175         if ((term = getenv("TERM")) == NULL)
 176                 stop("you must set the TERM environment variable");
 177         if (tgetent(tbuf, term) <= 0)
 178                 stop("cannot find your termcap");
 179         fill = combuf;
 180         {
 181                 register struct tcsinfo *p;
 182
 183                 for (p = tcstrings; p->tcaddr; p++)
 184                         *p->tcaddr = tgetstr(p->tcname, &fill);
 185         }
 186         {
 187                 register struct tcninfo *p;
 188
 189                 for (p = tcflags; p->tcaddr; p++)
 190                         *p->tcaddr = tgetflag(p->tcname);
 191                 for (p = tcnums; p->tcaddr; p++)
 192                         *p->tcaddr = tgetnum(p->tcname);
 193         }
 194         if (bsflag)
 195                 BC = "\b";
 196         else if (BC == NULL && bcstr != NULL)
 197                 BC = bcstr;
 198         if (CLstr == NULL)
 199                 stop("cannot clear screen");
 200         if (CMstr == NULL || UP == NULL || BC == NULL)
 201                 stop("cannot do random cursor positioning via tgoto()");
 202         PC = pcstr ? *pcstr : 0;
 203         if (sgnum >= 0 || xsflag)
 204                 SOstr = SEstr = NULL;
 205 #ifdef unneeded
 206         if (ncflag)
 207                 CRstr = NULL;
 208         else if (CRstr == NULL)
 209                 CRstr = "\r";
 210 #endif
 211 }
 212
 213 /* this foolery is needed to modify tty state `atomically' */
 214 static jmp_buf scr_onstop;
 215
 216 static void
 217 stopset(sig)
 218         int sig;
 219 {
 220         sigset_t sigset;
 221
 222         (void) signal(sig, SIG_DFL);
 223         (void) kill(getpid(), sig);
 224         sigemptyset(&sigset);
 225         sigaddset(&sigset, sig);
 226         (void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
 227         longjmp(scr_onstop, 1);
 228 }
 229
 230 static void
 231 scr_stop(sig)
 232         int sig;
 233 {
 234         sigset_t sigset;
 235
 236         scr_end();
 237         (void) kill(getpid(), sig);
 238         sigemptyset(&sigset);
 239         sigaddset(&sigset, sig);
 240         (void) sigprocmask(SIG_UNBLOCK, &sigset, (sigset_t *)0);
 241         scr_set();
 242         scr_msg(key_msg, 1);
 243 }
 244
 245 /*
 246  * Set up screen mode.
 247  */
 248 void
 249 scr_set()
 250 {
 251         struct winsize ws;
 252         struct termios newtt;
 253         sigset_t sigset, osigset;
 254         void (*ttou) __P((int));
 255
 256         sigemptyset(&sigset);
 257         sigaddset(&sigset, SIGTSTP);
 258         sigaddset(&sigset, SIGTTOU);
 259         (void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
 260         if ((tstp = signal(SIGTSTP, stopset)) == SIG_IGN)
 261                 (void) signal(SIGTSTP, SIG_IGN);
 262         if ((ttou = signal(SIGTTOU, stopset)) == SIG_IGN)
 263                 (void) signal(SIGTTOU, SIG_IGN);
 264         /*
 265          * At last, we are ready to modify the tty state.  If
 266          * we stop while at it, stopset() above will longjmp back
 267          * to the setjmp here and we will start over.
 268          */
 269         (void) setjmp(scr_onstop);
 270         (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
 271         Rows = 0, Cols = 0;
 272         if (ioctl(0, TIOCGWINSZ, &ws) == 0) {
 273                 Rows = ws.ws_row;
 274                 Cols = ws.ws_col;
 275         }
 276         if (Rows == 0)
 277                 Rows = LInum;
 278         if (Cols == 0)
 279         Cols = COnum;
 280         if (Rows < MINROWS || Cols < MINCOLS) {
 281                 (void) fprintf(stderr,
 282                     "the screen is too small: must be at least %d x %d",
 283                     MINROWS, MINCOLS);
 284                 stop("");       /* stop() supplies \n */
 285         }
 286         if (tcgetattr(0, &oldtt) < 0)
 287                 stop("tcgetattr() fails");
 288         newtt = oldtt;
 289         newtt.c_lflag &= ~(ICANON|ECHO);
 290         newtt.c_oflag &= ~OXTABS;
 291         if (tcsetattr(0, TCSADRAIN, &newtt) < 0)
 292                 stop("tcsetattr() fails");
 293         ospeed = cfgetospeed(&newtt);
 294         (void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
 295
 296         /*
 297          * We made it.  We are now in screen mode, modulo TIstr
 298          * (which we will fix immediately).
 299          */
 300         if (TIstr)
 301                 putstr(TIstr);  /* termcap(5) says this is not padded */
 302         if (tstp != SIG_IGN)
 303                 (void) signal(SIGTSTP, scr_stop);
 304         if (ttou != SIG_IGN)
 305                 (void) signal(SIGTTOU, ttou);
 306
 307         isset = 1;
 308         (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
 309         scr_clear();
 310 }
 311
 312 /*
 313  * End screen mode.
 314  */
 315 void
 316 scr_end()
 317 {
 318         sigset_t sigset, osigset;
 319
 320         sigemptyset(&sigset);
 321         sigaddset(&sigset, SIGTSTP);
 322         sigaddset(&sigset, SIGTTOU);
 323         (void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
 324         /* move cursor to last line */
 325         if (LLstr)
 326                 putstr(LLstr);  /* termcap(5) says this is not padded */
 327         else
 328                 moveto(Rows - 1, 0);
 329         /* exit screen mode */
 330         if (TEstr)
 331                 putstr(TEstr);  /* termcap(5) says this is not padded */
 332         (void) fflush(stdout);
 333         (void) tcsetattr(0, TCSADRAIN, &oldtt);
 334         isset = 0;
 335         /* restore signals */
 336         (void) signal(SIGTSTP, tstp);
 337         (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
 338 }
 339
 340 void
 341 stop(why)
 342         char *why;
 343 {
 344
 345         if (isset)
 346                 scr_end();
 347         (void) fprintf(stderr, "aborting: %s\n", why);
 348         exit(1);
 349 }
 350
 351 /*
 352  * Clear the screen, forgetting the current contents in the process.
 353  */
 354 void
 355 scr_clear()
 356 {
 357
 358         putpad(CLstr);
 359         curscore = -1;
 360         bzero((char *)curscreen, sizeof(curscreen));
 361 }
 362
 363 #if vax && !__GNUC__
 364 typedef int regcell;    /* pcc is bad at `register char', etc */
 365 #else
 366 typedef cell regcell;
 367 #endif
 368
 369 /*
 370  * Update the screen.
 371  */
 372 void
 373 scr_update()
 374 {
 375         register cell *bp, *sp;
 376         register regcell so, cur_so = 0;
 377         register int i, ccol, j;
 378         sigset_t sigset, osigset;
 379
 380         sigemptyset(&sigset);
 381         sigaddset(&sigset, SIGTSTP);
 382         (void) sigprocmask(SIG_BLOCK, &sigset, &osigset);
 383
 384         /* always leave cursor after last displayed point */
 385         curscreen[D_LAST * B_COLS - 1] = -1;
 386
 387         if (score != curscore) {
 388                 if (HOstr)
 389                         putpad(HOstr);
 390                 else
 391                         moveto(0, 0);
 392                 (void) printf("%d", score);
 393                 curscore = score;
 394         }
 395
 396         bp = &board[D_FIRST * B_COLS];
 397         sp = &curscreen[D_FIRST * B_COLS];
 398         for (j = D_FIRST; j < D_LAST; j++) {
 399                 ccol = -1;
 400                 for (i = 0; i < B_COLS; bp++, sp++, i++) {
 401                         if (*sp == (so = *bp))
 402                                 continue;
 403                         *sp = so;
 404                         if (i != ccol) {
 405                                 if (cur_so && MSflag) {
 406                                         putpad(SEstr);
 407                                         cur_so = 0;
 408                                 }
 409                                 moveto(RTOD(j), CTOD(i));
 410                         }
 411                         if (SOstr) {
 412                                 if (so != cur_so) {
 413                                         putpad(so ? SOstr : SEstr);
 414                                         cur_so = so;
 415                                 }
 416                                 putstr("  ");
 417                         } else
 418                                 putstr(so ? "XX" : "  ");
 419                         ccol = i + 1;
 420                         /*
 421                          * Look ahead a bit, to avoid extra motion if
 422                          * we will be redrawing the cell after the next.
 423                          * Motion probably takes four or more characters,
 424                          * so we save even if we rewrite two cells
 425                          * `unnecessarily'.  Skip it all, though, if
 426                          * the next cell is a different color.
 427                          */
 428 #define STOP (B_COLS - 3)
 429                         if (i > STOP || sp[1] != bp[1] || so != bp[1])
 430                                 continue;
 431                         if (sp[2] != bp[2])
 432                                 sp[1] = -1;
 433                         else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
 434                                 sp[2] = -1;
 435                                 sp[1] = -1;
 436                         }
 437                 }
 438         }
 439         if (cur_so)
 440                 putpad(SEstr);
 441         (void) fflush(stdout);
 442         (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
 443 }
 444
 445 /*
 446  * Write a message (set!=0), or clear the same message (set==0).
 447  * (We need its length in case we have to overwrite with blanks.)
 448  */
 449 void
 450 scr_msg(s, set)
 451         register char *s;
 452         int set;
 453 {
 454
 455         if (set || CEstr == NULL) {
 456                 register int l = strlen(s);
 457
 458                 moveto(Rows - 2, ((Cols - l) >> 1) - 1);
 459                 if (set)
 460                         putstr(s);
 461                 else
 462                         while (--l >= 0)
 463                                 (void) putchar(' ');
 464         } else {
 465                 moveto(Rows - 2, 0);
 466                 putpad(CEstr);
 467         }
 468 }