hack/hack.unix.c

   1 /*      $NetBSD: hack.unix.c,v 1.18 2019/02/03 10:48:46 mrg Exp $       */
   2
   3 /*
   4  * Copyright (c) 1985, Stichting Centrum voor Wiskunde en Informatica,
   5  * Amsterdam
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are
  10  * met:
  11  *
  12  * - Redistributions of source code must retain the above copyright notice,
  13  * this list of conditions and the following disclaimer.
  14  *
  15  * - 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  *
  19  * - Neither the name of the Stichting Centrum voor Wiskunde en
  20  * Informatica, nor the names of its contributors may be used to endorse or
  21  * promote products derived from this software without specific prior
  22  * written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  25  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  26  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  27  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
  28  * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  29  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  30  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  31  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 /*
  38  * Copyright (c) 1982 Jay Fenlason <hack@gnu.org>
  39  * All rights reserved.
  40  *
  41  * Redistribution and use in source and binary forms, with or without
  42  * modification, are permitted provided that the following conditions
  43  * are met:
  44  * 1. Redistributions of source code must retain the above copyright
  45  *    notice, this list of conditions and the following disclaimer.
  46  * 2. Redistributions in binary form must reproduce the above copyright
  47  *    notice, this list of conditions and the following disclaimer in the
  48  *    documentation and/or other materials provided with the distribution.
  49  * 3. The name of the author may not be used to endorse or promote products
  50  *    derived from this software without specific prior written permission.
  51  *
  52  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  53  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  54  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  55  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  56  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  57  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  58  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  59  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  60  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  61  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  62  */
  63
  64 #include <sys/cdefs.h>
  65 #ifndef lint
  66 __RCSID("$NetBSD: hack.unix.c,v 1.18 2019/02/03 10:48:46 mrg Exp $");
  67 #endif                          /* not lint */
  68
  69 /* This file collects some Unix dependencies; hack.pager.c contains some more */
  70
  71 /*
  72  * The time is used for:
  73  *      - seed for random()
  74  *      - year on tombstone and yymmdd in record file
  75  *      - phase of the moon (various monsters react to NEW_MOON or FULL_MOON)
  76  *      - night and midnight (the undead are dangerous at midnight)
  77  *      - determination of what files are "very old"
  78  */
  79
  80 #include <errno.h>
  81 #include <sys/types.h>  /* for time_t and stat */
  82 #include <sys/stat.h>
  83 #ifdef BSD
  84 #include <sys/time.h>
  85 #else
  86 #include <time.h>
  87 #endif  /* BSD */
  88 #include <stdlib.h>
  89 #include <unistd.h>
  90 #include <signal.h>
  91 #include <fcntl.h>
  92
  93 #include "hack.h"               /* mainly for strchr() which depends on BSD */
  94 #include "extern.h"
  95
  96 extern int locknum;
  97
  98 static struct tm *getlt(void);
  99 static int veryold(int);
 100
 101
 102 void
 103 setrandom(void)
 104 {
 105         (void) srandom((int) time((time_t *) 0));
 106 }
 107
 108 static struct tm *
 109 getlt(void)
 110 {
 111         time_t          date;
 112
 113         (void) time(&date);
 114         return (localtime(&date));
 115 }
 116
 117 int
 118 getyear(void)
 119 {
 120         return (1900 + getlt()->tm_year);
 121 }
 122
 123 char           *
 124 getdatestr(void)
 125 {
 126         static char     datestr[32];
 127         struct tm      *lt = getlt();
 128
 129         (void) snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
 130                        lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
 131         return (datestr);
 132 }
 133
 134 int
 135 phase_of_the_moon(void)
 136 {                               /* 0-7, with 0: new, 4: full *//* moon
 137                                  * period: 29.5306 days */
 138         /* year: 365.2422 days */
 139         struct tm      *lt = getlt();
 140         int             epact, diy, golden;
 141
 142         diy = lt->tm_yday;
 143         golden = (lt->tm_year % 19) + 1;
 144         epact = (11 * golden + 18) % 30;
 145         if ((epact == 25 && golden > 11) || epact == 24)
 146                 epact++;
 147
 148         return ((((((diy + epact) * 6) + 11) % 177) / 22) & 7);
 149 }
 150
 151 int
 152 night(void)
 153 {
 154         int             hour = getlt()->tm_hour;
 155
 156         return (hour < 6 || hour > 21);
 157 }
 158
 159 int
 160 midnight(void)
 161 {
 162         return (getlt()->tm_hour == 0);
 163 }
 164
 165 static struct stat buf, hbuf;
 166
 167 void
 168 gethdate(char *name)
 169 {
 170 #if 0
 171         /* old version - for people short of space */
 172
 173         char *np;
 174
 175         if(stat(name, &hbuf))
 176             error("Cannot get status of %s.",
 177                 (np = strrchr(name, '/')) ? np+1 : name);
 178 #else
 179         /* version using PATH from: seismo!gregc@ucsf-cgl.ARPA (Greg Couch) */
 180
 181
 182         /*
 183          * The problem with   #include  <sys/param.h>   is that this include file
 184          * does not exist on all systems, and moreover, that it sometimes includes
 185          * <sys/types.h> again, so that the compiler sees these typedefs twice.
 186          */
 187 #define         MAXPATHLEN      1024
 188
 189         const char           *np, *path;
 190         char            filename[MAXPATHLEN + 1];
 191         if (strchr(name, '/') != NULL || (path = getenv("PATH")) == NULL)
 192                 path = "";
 193
 194         for (;;) {
 195                 if ((np = strchr(path, ':')) == NULL)
 196                         np = path + strlen(path);       /* point to end str */
 197                 if (np - path <= 1)     /* %% */
 198                         (void) strlcpy(filename, name, sizeof(filename));
 199                 else {
 200                         (void) snprintf(filename, sizeof(filename),
 201                                 "%.*s/%s",
 202                                 (int)(np - path), path, name);
 203                 }
 204                 if (stat(filename, &hbuf) == 0)
 205                         return;
 206                 if (*np == '\0')
 207                         break;
 208                 path = np + 1;
 209         }
 210         error("Cannot get status of %s.",
 211               (np = strrchr(name, '/')) ? np + 1 : name);
 212 #endif
 213 }
 214
 215 int
 216 uptodate(int fd)
 217 {
 218         if (fstat(fd, &buf)) {
 219                 pline("Cannot get status of saved level? ");
 220                 return (0);
 221         }
 222         if (buf.st_mtime < hbuf.st_mtime) {
 223                 pline("Saved level is out of date. ");
 224                 return (0);
 225         }
 226         return (1);
 227 }
 228
 229 /* see whether we should throw away this xlock file */
 230 static int
 231 veryold(int fd)
 232 {
 233         int             i;
 234         time_t          date;
 235
 236         if (fstat(fd, &buf))
 237                 return (0);     /* cannot get status */
 238         if (buf.st_size != sizeof(int))
 239                 return (0);     /* not an xlock file */
 240         (void) time(&date);
 241         if (date - buf.st_mtime < 3L * 24L * 60L * 60L) {       /* recent */
 242                 int             lockedpid;      /* should be the same size as
 243                                                  * hackpid */
 244
 245                 if (read(fd, &lockedpid, sizeof(lockedpid)) !=
 246                     sizeof(lockedpid))
 247                         /* strange ... */
 248                         return (0);
 249
 250                 /*
 251                  * From: Rick Adams <seismo!rick> This will work on
 252                  * 4.1cbsd, 4.2bsd and system 3? & 5. It will do nothing
 253                  * on V7 or 4.1bsd.
 254                  */
 255                 if (!(kill(lockedpid, 0) == -1 && errno == ESRCH))
 256                         return (0);
 257         }
 258         (void) close(fd);
 259         for (i = 1; i <= MAXLEVEL; i++) {       /* try to remove all */
 260                 glo(i);
 261                 (void) unlink(lock);
 262         }
 263         glo(0);
 264         if (unlink(lock))
 265                 return (0);     /* cannot remove it */
 266         return (1);             /* success! */
 267 }
 268
 269 void
 270 getlock(void)
 271 {
 272         int             i = 0, fd;
 273
 274         (void) fflush(stdout);
 275
 276         /* we ignore QUIT and INT at this point */
 277         if (link(HLOCK, LLOCK) == -1) {
 278                 int             errnosv = errno;
 279
 280                 perror(HLOCK);
 281                 printf("Cannot link %s to %s\n", LLOCK, HLOCK);
 282                 switch (errnosv) {
 283                 case ENOENT:
 284                         printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
 285                         break;
 286                 case EACCES:
 287                         printf("It seems you don't have write permission here.\n");
 288                         break;
 289                 case EEXIST:
 290                         printf("(Try again or rm %s.)\n", LLOCK);
 291                         break;
 292                 default:
 293                         printf("I don't know what is wrong.");
 294                 }
 295                 getret();
 296                 error("%s", "");
 297                 /* NOTREACHED */
 298         }
 299         regularize(lock);
 300         glo(0);
 301         if (locknum > 25)
 302                 locknum = 25;
 303
 304         do {
 305                 if (locknum)
 306                         lock[0] = 'a' + i++;
 307
 308                 if ((fd = open(lock, O_RDONLY)) == -1) {
 309                         if (errno == ENOENT)
 310                                 goto gotlock;   /* no such file */
 311                         perror(lock);
 312                         (void) unlink(LLOCK);
 313                         error("Cannot open %s", lock);
 314                 }
 315                 if (veryold(fd))/* if true, this closes fd and unlinks lock */
 316                         goto gotlock;
 317                 (void) close(fd);
 318         } while (i < locknum);
 319
 320         (void) unlink(LLOCK);
 321         error(locknum ? "Too many hacks running now."
 322               : "There is a game in progress under your name.");
 323 gotlock:
 324         fd = creat(lock, FMASK);
 325         if (unlink(LLOCK) == -1)
 326                 error("Cannot unlink %s.", LLOCK);
 327         if (fd == -1) {
 328                 error("cannot creat lock file.");
 329         } else {
 330                 if (write(fd, &hackpid, sizeof(hackpid))
 331                     != sizeof(hackpid)) {
 332                         error("cannot write lock");
 333                 }
 334                 if (close(fd) == -1) {
 335                         error("cannot close lock");
 336                 }
 337         }
 338 }
 339
 340 #ifdef MAIL
 341
 342 /*
 343  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
 344  * I don't know the details of his implementation.]
 345  * { Later note: he disliked my calling a general mailreader and felt that
 346  *   hack should do the paging itself. But when I get mail, I want to put it
 347  *   in some folder, reply, etc. - it would be unreasonable to put all these
 348  *   functions in hack. }
 349  * The mail daemon '2' is at present not a real monster, but only a visual
 350  * effect. Thus, makemon() is superfluous. This might become otherwise,
 351  * however. The motion of '2' is less restrained than usual: diagonal moves
 352  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
 353  * in a ROOM, even when you are Blind.
 354  * Its path should be longer when you are Telepat-hic and Blind.
 355  *
 356  * Interesting side effects:
 357  *      - You can get rich by sending yourself a lot of mail and selling
 358  *        it to the shopkeeper. Unfortunately mail isn't very valuable.
 359  *      - You might die in case '2' comes along at a critical moment during
 360  *        a fight and delivers a scroll the weight of which causes you to
 361  *        collapse.
 362  *
 363  * Possible extensions:
 364  *      - Open the file MAIL and do fstat instead of stat for efficiency.
 365  *        (But sh uses stat, so this cannot be too bad.)
 366  *      - Examine the mail and produce a scroll of mail called "From somebody".
 367  *      - Invoke MAILREADER in such a way that only this single letter is read.
 368  *
 369  *      - Make him lose his mail when a Nymph steals the letter.
 370  *      - Do something to the text when the scroll is enchanted or cancelled.
 371  */
 372 #include        "def.mkroom.h"
 373 static struct stat omstat, nmstat;
 374 static char    *mailbox;
 375 static long     laststattime;
 376
 377 void
 378 getmailstatus(void)
 379 {
 380         if (!(mailbox = getenv("MAIL")))
 381                 return;
 382         if (stat(mailbox, &omstat)) {
 383 #ifdef PERMANENT_MAILBOX
 384                 pline("Cannot get status of MAIL=%s .", mailbox);
 385                 mailbox = 0;
 386 #else
 387                 omstat.st_mtime = 0;
 388 #endif  /* PERMANENT_MAILBOX */
 389         }
 390 }
 391
 392 void
 393 ckmailstatus(void)
 394 {
 395         if (!mailbox
 396 #ifdef MAILCKFREQ
 397             || moves < laststattime + MAILCKFREQ
 398 #endif  /* MAILCKFREQ */
 399                 )
 400                 return;
 401         laststattime = moves;
 402         if (stat(mailbox, &nmstat)) {
 403 #ifdef PERMANENT_MAILBOX
 404                 pline("Cannot get status of MAIL=%s anymore.", mailbox);
 405                 mailbox = 0;
 406 #else
 407                 nmstat.st_mtime = 0;
 408 #endif  /* PERMANENT_MAILBOX */
 409         } else if (nmstat.st_mtime > omstat.st_mtime) {
 410                 if (nmstat.st_size)
 411                         newmail();
 412                 getmailstatus();/* might be too late ... */
 413         }
 414 }
 415
 416 void
 417 newmail(void)
 418 {
 419         /* produce a scroll of mail */
 420         struct obj     *obj;
 421         struct monst   *md;
 422
 423         obj = mksobj(SCR_MAIL);
 424         if (md = makemon(&pm_mail_daemon, u.ux, u.uy))  /* always succeeds */
 425                 mdrush(md, 0);
 426
 427         pline("\"Hello, %s! I have some mail for you.\"", plname);
 428         if (md) {
 429                 if (dist(md->mx, md->my) > 2)
 430                         pline("\"Catch!\"");
 431                 more();
 432
 433                 /* let him disappear again */
 434                 mdrush(md, 1);
 435                 mondead(md);
 436         }
 437         obj = addinv(obj);
 438         (void) identify(obj);   /* set known and do prinv() */
 439 }
 440
 441 /* make md run through the cave */
 442 void
 443 mdrush(struct monst *md, boolean away)
 444 {
 445         int             uroom = inroom(u.ux, u.uy);
 446         if (uroom >= 0) {
 447                 int             tmp = rooms[uroom].fdoor;
 448                 int             cnt = rooms[uroom].doorct;
 449                 int             fx = u.ux, fy = u.uy;
 450                 while (cnt--) {
 451                         if (dist(fx, fy) < dist(doors[tmp].x, doors[tmp].y)) {
 452                                 fx = doors[tmp].x;
 453                                 fy = doors[tmp].y;
 454                         }
 455                         tmp++;
 456                 }
 457                 tmp_at(-1, md->data->mlet);     /* open call */
 458                 if (away) {     /* interchange origin and destination */
 459                         unpmon(md);
 460                         tmp = fx;
 461                         fx = md->mx;
 462                         md->mx = tmp;
 463                         tmp = fy;
 464                         fy = md->my;
 465                         md->my = tmp;
 466                 }
 467                 while (fx != md->mx || fy != md->my) {
 468                         int             dx, dy, nfx = fx, nfy = fy, d1,
 469                                         d2;
 470
 471                         tmp_at(fx, fy);
 472                         d1 = DIST(fx, fy, md->mx, md->my);
 473                         for (dx = -1; dx <= 1; dx++)
 474                                 for (dy = -1; dy <= 1; dy++)
 475                                         if (dx || dy) {
 476                                                 d2 = DIST(fx + dx, fy + dy, md->mx, md->my);
 477                                                 if (d2 < d1) {
 478                                                         d1 = d2;
 479                                                         nfx = fx + dx;
 480                                                         nfy = fy + dy;
 481                                                 }
 482                                         }
 483                         if (nfx != fx || nfy != fy) {
 484                                 fx = nfx;
 485                                 fy = nfy;
 486                         } else {
 487                                 if (!away) {
 488                                         md->mx = fx;
 489                                         md->my = fy;
 490                                 }
 491                                 break;
 492                         }
 493                 }
 494                 tmp_at(-1, -1); /* close call */
 495         }
 496         if (!away)
 497                 pmon(md);
 498 }
 499
 500 void
 501 readmail(void)
 502 {
 503 #ifdef DEF_MAILREADER           /* This implies that UNIX is defined */
 504         char           *mr = 0;
 505         more();
 506         if (!(mr = getenv("MAILREADER")))
 507                 mr = DEF_MAILREADER;
 508         if (child(1)) {
 509                 execl(mr, mr, (char *)NULL);
 510                 exit(1);
 511         }
 512 #else   /* DEF_MAILREADER */
 513         (void) page_file(mailbox, FALSE);
 514 #endif  /* DEF_MAILREADER */
 515         /*
 516          * get new stat; not entirely correct: there is a small time window
 517          * where we do not see new mail
 518          */
 519         getmailstatus();
 520 }
 521 #endif  /* MAIL */
 522
 523 /*
 524  * normalize file name - we don't like ..'s or /'s
 525  */
 526 void
 527 regularize(char *s)
 528 {
 529         char           *lp;
 530
 531         while ((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
 532                 *lp = '_';
 533 }