tetris/screen.c

   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
  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  * Capabilities from TERMCAP.
  72  */
  73 short   ospeed;
  74
  75 static 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 */
  88 char
  89         *SEstr,                 /* end standout mode */
  90         *SOstr;                 /* begin standout mode */
  91 static int
  92         COnum,                  /* co# value */
  93         LInum,                  /* li# value */
  94         MSflag;                 /* can move in standout mode */
  95
  96
  97 struct 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
 120 static struct tinfo *info;
 121
 122 /*
 123  * Routine used by tputs().
 124  */
 125 int
 126 put(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
 140 void
 141 moveto(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  */
 152 void
 153 scr_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' */
 217 static jmp_buf scr_onstop;
 218
 219 static void
 220 stopset(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
 233 static void
 234 scr_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  */
 251 void
 252 scr_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  */
 318 void
 319 scr_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
 343 void
 344 stop(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  */
 357 void
 358 scr_clear()
 359 {
 360
 361         putpad(CLstr);
 362         curscore = -1;
 363         memset((char *)curscreen, 0, sizeof(curscreen));
 364 }
 365
 366 #if vax && !__GNUC__
 367 typedef int regcell;    /* pcc is bad at `register char', etc */
 368 #else
 369 typedef cell regcell;
 370 #endif
 371
 372 /*
 373  * Update the screen.
 374  */
 375 void
 376 scr_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  */
 487 void
 488 scr_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 }