tetris/screen.c

   1 /*      $NetBSD: screen.c,v 1.23 2009/05/25 04:33:53 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(int c)
 127 {
 128
 129         return (putchar(c));
 130 }
 131
 132 /*
 133  * putstr() is for unpadded strings (either as in termcap(5) or
 134  * simply literal strings); putpad() is for padded strings with
 135  * count=1.  (See screen.h for putpad().)
 136  */
 137 #define putstr(s)       (void)fputs(s, stdout)
 138
 139 void
 140 moveto(int r, int c)
 141 {
 142         char buf[256];
 143
 144         if (t_goto(info, CMstr, c, r, buf, 255) == 0)
 145                 putpad(buf);
 146 }
 147
 148 /*
 149  * Set up from termcap.
 150  */
 151 void
 152 scr_init(void)
 153 {
 154         static int bsflag, xsflag, sgnum;
 155 #ifdef unneeded
 156         static int ncflag;
 157 #endif
 158         char *term;
 159         static struct tcninfo { /* termcap numeric and flag info */
 160                 char tcname[3];
 161                 int *tcaddr;
 162         } tcflags[] = {
 163                 {"bs", &bsflag},
 164                 {"ms", &MSflag},
 165 #ifdef unneeded
 166                 {"nc", &ncflag},
 167 #endif
 168                 {"xs", &xsflag},
 169                 { {0}, NULL}
 170         }, tcnums[] = {
 171                 {"co", &COnum},
 172                 {"li", &LInum},
 173                 {"sg", &sgnum},
 174                 { {0}, NULL}
 175         };
 176         static char backspace[] = "\b";
 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 = backspace;
 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' */
 216 static jmp_buf scr_onstop;
 217
 218 static void
 219 stopset(int sig)
 220 {
 221         sigset_t set;
 222
 223         (void) signal(sig, SIG_DFL);
 224         (void) kill(getpid(), sig);
 225         sigemptyset(&set);
 226         sigaddset(&set, sig);
 227         (void) sigprocmask(SIG_UNBLOCK, &set, (sigset_t *)0);
 228         longjmp(scr_onstop, 1);
 229 }
 230
 231 static void
 232 scr_stop(int sig)
 233 {
 234         sigset_t set;
 235
 236         scr_end();
 237         (void) kill(getpid(), sig);
 238         sigemptyset(&set);
 239         sigaddset(&set, sig);
 240         (void) sigprocmask(SIG_UNBLOCK, &set, (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(void)
 250 {
 251         struct winsize ws;
 252         struct termios newtt;
 253         sigset_t nsigset, osigset;
 254         void (*ttou)(int);
 255
 256         sigemptyset(&nsigset);
 257         sigaddset(&nsigset, SIGTSTP);
 258         sigaddset(&nsigset, SIGTTOU);
 259         (void) sigprocmask(SIG_BLOCK, &nsigset, &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 %dx%d, ",
 283                     MINCOLS, MINROWS);
 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, &nsigset, &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(void)
 317 {
 318         sigset_t nsigset, osigset;
 319
 320         sigemptyset(&nsigset);
 321         sigaddset(&nsigset, SIGTSTP);
 322         sigaddset(&nsigset, SIGTTOU);
 323         (void) sigprocmask(SIG_BLOCK, &nsigset, &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(const char *why)
 342 {
 343
 344         if (isset)
 345                 scr_end();
 346         (void) fprintf(stderr, "aborting: %s\n", why);
 347         exit(1);
 348 }
 349
 350 /*
 351  * Clear the screen, forgetting the current contents in the process.
 352  */
 353 void
 354 scr_clear(void)
 355 {
 356
 357         putpad(CLstr);
 358         curscore = -1;
 359         memset((char *)curscreen, 0, sizeof(curscreen));
 360 }
 361
 362 #if vax && !__GNUC__
 363 typedef int regcell;    /* pcc is bad at `register char', etc */
 364 #else
 365 typedef cell regcell;
 366 #endif
 367
 368 /*
 369  * Update the screen.
 370  */
 371 void
 372 scr_update(void)
 373 {
 374         cell *bp, *sp;
 375         regcell so, cur_so = 0;
 376         int i, ccol, j;
 377         sigset_t nsigset, osigset;
 378         static const struct shape *lastshape;
 379
 380         sigemptyset(&nsigset);
 381         sigaddset(&nsigset, SIGTSTP);
 382         (void) sigprocmask(SIG_BLOCK, &nsigset, &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("Score: %d", score);
 393                 curscore = score;
 394         }
 395
 396         /* draw preview of nextpattern */
 397         if (showpreview && (nextshape != lastshape)) {
 398                 static int r=5, c=2;
 399                 int tr, tc, t;
 400
 401                 lastshape = nextshape;
 402
 403                 /* clean */
 404                 putpad(SEstr);
 405                 moveto(r-1, c-1); putstr("          ");
 406                 moveto(r,   c-1); putstr("          ");
 407                 moveto(r+1, c-1); putstr("          ");
 408                 moveto(r+2, c-1); putstr("          ");
 409
 410                 moveto(r-3, c-2);
 411                 putstr("Next shape:");
 412
 413                 /* draw */
 414                 putpad(SOstr);
 415                 moveto(r, 2*c);
 416                 putstr("  ");
 417                 for(i=0; i<3; i++) {
 418                         t = c + r*B_COLS;
 419                         t += nextshape->off[i];
 420
 421                         tr = t / B_COLS;
 422                         tc = t % B_COLS;
 423
 424                         moveto(tr, 2*tc);
 425                         putstr("  ");
 426                 }
 427                 putpad(SEstr);
 428         }
 429
 430         bp = &board[D_FIRST * B_COLS];
 431         sp = &curscreen[D_FIRST * B_COLS];
 432         for (j = D_FIRST; j < D_LAST; j++) {
 433                 ccol = -1;
 434                 for (i = 0; i < B_COLS; bp++, sp++, i++) {
 435                         if (*sp == (so = *bp))
 436                                 continue;
 437                         *sp = so;
 438                         if (i != ccol) {
 439                                 if (cur_so && MSflag) {
 440                                         putpad(SEstr);
 441                                         cur_so = 0;
 442                                 }
 443                                 moveto(RTOD(j), CTOD(i));
 444                         }
 445                         if (SOstr) {
 446                                 if (so != cur_so) {
 447                                         putpad(so ? SOstr : SEstr);
 448                                         cur_so = so;
 449                                 }
 450                                 putstr("  ");
 451                         } else
 452                                 putstr(so ? "XX" : "  ");
 453                         ccol = i + 1;
 454                         /*
 455                          * Look ahead a bit, to avoid extra motion if
 456                          * we will be redrawing the cell after the next.
 457                          * Motion probably takes four or more characters,
 458                          * so we save even if we rewrite two cells
 459                          * `unnecessarily'.  Skip it all, though, if
 460                          * the next cell is a different color.
 461                          */
 462 #define STOP (B_COLS - 3)
 463                         if (i > STOP || sp[1] != bp[1] || so != bp[1])
 464                                 continue;
 465                         if (sp[2] != bp[2])
 466                                 sp[1] = -1;
 467                         else if (i < STOP && so == bp[2] && sp[3] != bp[3]) {
 468                                 sp[2] = -1;
 469                                 sp[1] = -1;
 470                         }
 471                 }
 472         }
 473         if (cur_so)
 474                 putpad(SEstr);
 475         (void) fflush(stdout);
 476         (void) sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
 477 }
 478
 479 /*
 480  * Write a message (set!=0), or clear the same message (set==0).
 481  * (We need its length in case we have to overwrite with blanks.)
 482  */
 483 void
 484 scr_msg(char *s, int set)
 485 {
 486
 487         if (set || CEstr == NULL) {
 488                 int l = strlen(s);
 489
 490                 moveto(Rows - 2, ((Cols - l) >> 1) - 1);
 491                 if (set)
 492                         putstr(s);
 493                 else
 494                         while (--l >= 0)
 495                                 (void) putchar(' ');
 496         } else {
 497                 moveto(Rows - 2, 0);
 498                 putpad(CEstr);
 499         }
 500 }