games/hack/hack.unix.c

   1 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
   2 /* hack.unix.c - version 1.0.3 */
   3 /* $FreeBSD: src/games/hack/hack.unix.c,v 1.8 1999/11/16 02:57:13 billf Exp $ */
   4
   5 /* This file collects some Unix dependencies; hack.pager.c contains some more */
   6
   7 /*
   8  * The time is used for:
   9  *      - seed for random()
  10  *      - year on tombstone and yymmdd in record file
  11  *      - phase of the moon (various monsters react to NEW_MOON or FULL_MOON)
  12  *      - night and midnight (the undead are dangerous at midnight)
  13  *      - determination of what files are "very old"
  14  */
  15
  16 #include <errno.h>
  17 #include "hack.h"
  18
  19 #include <sys/types.h>  /* for time_t and stat */
  20 #include <sys/stat.h>
  21 #include <time.h>
  22
  23 static struct tm *getlt(void);
  24 static bool  veryold(int);
  25 #ifdef MAIL
  26 static void  newmail(void);
  27 static void  mdrush(struct monst *, bool);
  28 #endif
  29
  30 void
  31 setrandom(void)
  32 {
  33         srandomdev();
  34 }
  35
  36 static struct tm *
  37 getlt(void)
  38 {
  39         time_t date;
  40
  41         time(&date);
  42         return (localtime(&date));
  43 }
  44
  45 int
  46 getyear(void)
  47 {
  48         return (1900 + getlt()->tm_year);
  49 }
  50
  51 char *
  52 getdate(void)
  53 {
  54         static char datestr[7];
  55         struct tm *lt = getlt();
  56
  57         snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
  58             lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
  59         return (datestr);
  60 }
  61
  62 int
  63 phase_of_the_moon(void)                 /* 0-7, with 0: new, 4: full */
  64 {                                       /* moon period: 29.5306 days */
  65                                         /* year: 365.2422 days */
  66         struct tm *lt = getlt();
  67         int epact, diy, golden;
  68
  69         diy = lt->tm_yday;
  70         golden = (lt->tm_year % 19) + 1;
  71         epact = (11 * golden + 18) % 30;
  72         if ((epact == 25 && golden > 11) || epact == 24)
  73                 epact++;
  74
  75         return ((((((diy + epact) * 6) + 11) % 177) / 22) & 7);
  76 }
  77
  78 bool
  79 night(void)
  80 {
  81         int hour = getlt()->tm_hour;
  82
  83         return (hour < 6 || hour > 21);
  84 }
  85
  86 bool
  87 midnight(void)
  88 {
  89         return (getlt()->tm_hour == 0);
  90 }
  91
  92 struct stat buf, hbuf;
  93
  94 void
  95 gethdate(const char *name)
  96 {
  97 /* old version - for people short of space */
  98         char *np;
  99
 100         name = "/usr/games/hide/hack";
 101         if (stat(name, &hbuf))
 102                 error("Cannot get status of %s.",
 103                       (np = strrchr(name, '/')) ? np + 1 : name);
 104 }
 105
 106 bool
 107 uptodate(int fd)
 108 {
 109         if (fstat(fd, &buf)) {
 110                 pline("Cannot get status of saved level? ");
 111                 return (0);
 112         }
 113         if (buf.st_mtime < hbuf.st_mtime) {
 114                 pline("Saved level is out of date. ");
 115                 return (0);
 116         }
 117         return (1);
 118 }
 119
 120 /* see whether we should throw away this xlock file */
 121 static bool
 122 veryold(int fd)
 123 {
 124         int i;
 125         time_t date;
 126
 127         if (fstat(fd, &buf))                    /* cannot get status */
 128                 return (0);
 129         if (buf.st_size != sizeof(int))         /* not an xlock file */
 130                 return (0);
 131         time(&date);
 132         if (date - buf.st_mtime < 3L * 24L * 60L * 60L) {       /* recent */
 133                 int lockedpid;  /* should be the same size as hackpid */
 134
 135                 if (read(fd, (char *)&lockedpid, sizeof(lockedpid)) !=
 136                     sizeof(lockedpid))
 137                         /* strange ... */
 138                         return (0);
 139
 140                 /* From: Rick Adams <seismo!rick> */
 141                 /* This will work on 4.1cbsd, 4.2bsd and system 3? & 5. */
 142                 /* It will do nothing on V7 or 4.1bsd. */
 143                 if (!(kill(lockedpid, 0) == -1 && errno == ESRCH))
 144                         return (0);
 145         }
 146         close(fd);
 147         for (i = 1; i <= MAXLEVEL; i++) {       /* try to remove all */
 148                 glo(i);
 149                 unlink(lock);
 150         }
 151         glo(0);
 152         if (unlink(lock))                       /* cannot remove it */
 153                 return (0);
 154         return (1);                             /* success! */
 155 }
 156
 157 void
 158 getlock(void)
 159 {
 160         int i = 0, fd;
 161
 162         fflush(stdout);
 163
 164         /* we ignore QUIT and INT at this point */
 165         if ((link(HLOCK, LLOCK) == -1) && (symlink(HLOCK, LLOCK) == -1)) {
 166                 int errnosv = errno;
 167
 168                 perror(HLOCK);
 169                 printf("Cannot link %s to %s\n", LLOCK, HLOCK);
 170                 switch (errnosv) {
 171                 case ENOENT:
 172                         printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
 173                         break;
 174                 case EACCES:
 175                         printf("It seems you don't have write permission here.\n");
 176                         break;
 177                 case EEXIST:
 178                         printf("(Try again or rm %s.)\n", LLOCK);
 179                         break;
 180                 default:
 181                         printf("I don't know what is wrong.");
 182                 }
 183                 getret();
 184                 error("%s", "");
 185                 /* NOTREACHED */
 186         }
 187
 188         regularize(lock);
 189         glo(0);
 190         if (locknum > 25)
 191                 locknum = 25;
 192
 193         do {
 194                 if (locknum)
 195                         lock[0] = 'a' + i++;
 196
 197                 if ((fd = open(lock, O_RDONLY)) == -1) {
 198                         if (errno == ENOENT)    /* no such file */
 199                                 goto gotlock;
 200                         perror(lock);
 201                         unlink(LLOCK);
 202                         error("Cannot open %s", lock);
 203                 }
 204
 205                 if (veryold(fd)) /* if true, this closes fd and unlinks lock */
 206                         goto gotlock;
 207                 close(fd);
 208         } while (i < locknum);
 209
 210         unlink(LLOCK);
 211         error(locknum ? "Too many hacks running now."
 212               : "There is a game in progress under your name.");
 213 gotlock:
 214         fd = creat(lock, FMASK);
 215         if (unlink(LLOCK) == -1)
 216                 error("Cannot unlink %s.", LLOCK);
 217         if (fd == -1) {
 218                 error("cannot creat lock file.");
 219         } else {
 220                 if (write(fd, (char *)&hackpid, sizeof(hackpid))
 221                     != sizeof(hackpid))
 222                         error("cannot write lock");
 223                 if (close(fd) == -1)
 224                         error("cannot close lock");
 225         }
 226 }
 227
 228 #ifdef MAIL
 229
 230 /*
 231  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
 232  * I don't know the details of his implementation.]
 233  * { Later note: he disliked my calling a general mailreader and felt that
 234  *   hack should do the paging itself. But when I get mail, I want to put it
 235  *   in some folder, reply, etc. - it would be unreasonable to put all these
 236  *   functions in hack. }
 237  * The mail daemon '2' is at present not a real monster, but only a visual
 238  * effect. Thus, makemon() is superfluous. This might become otherwise,
 239  * however. The motion of '2' is less restrained than usual: diagonal moves
 240  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
 241  * in a ROOM, even when you are Blind.
 242  * Its path should be longer when you are Telepat-hic and Blind.
 243  *
 244  * Interesting side effects:
 245  *      - You can get rich by sending yourself a lot of mail and selling
 246  *        it to the shopkeeper. Unfortunately mail isn't very valuable.
 247  *      - You might die in case '2' comes along at a critical moment during
 248  *        a fight and delivers a scroll the weight of which causes you to
 249  *        collapse.
 250  *
 251  * Possible extensions:
 252  *      - Open the file MAIL and do fstat instead of stat for efficiency.
 253  *        (But sh uses stat, so this cannot be too bad.)
 254  *      - Examine the mail and produce a scroll of mail called "From somebody".
 255  *      - Invoke MAILREADER in such a way that only this single letter is read.
 256  *
 257  *      - Make him lose his mail when a Nymph steals the letter.
 258  *      - Do something to the text when the scroll is enchanted or cancelled.
 259  */
 260 #include "def.mkroom.h"
 261 static struct stat omstat, nmstat;
 262 static char *mailbox;
 263 static long laststattime;
 264
 265 void
 266 getmailstatus(void)
 267 {
 268         if (!(mailbox = getenv("MAIL")))
 269                 return;
 270         if (stat(mailbox, &omstat)) {
 271 #ifdef PERMANENT_MAILBOX
 272                 pline("Cannot get status of MAIL=%s .", mailbox);
 273                 mailbox = NULL;
 274 #else
 275                 omstat.st_mtime = 0;
 276 #endif /* PERMANENT_MAILBOX */
 277         }
 278 }
 279
 280 void
 281 ckmailstatus(void)
 282 {
 283         if (!mailbox
 284 #ifdef MAILCKFREQ
 285             || moves < laststattime + MAILCKFREQ
 286 #endif /* MAILCKFREQ */
 287             )
 288                 return;
 289         laststattime = moves;
 290         if (stat(mailbox, &nmstat)) {
 291 #ifdef PERMANENT_MAILBOX
 292                 pline("Cannot get status of MAIL=%s anymore.", mailbox);
 293                 mailbox = NULL;
 294 #else
 295                 nmstat.st_mtime = 0;
 296 #endif /* PERMANENT_MAILBOX */
 297         } else if (nmstat.st_mtime > omstat.st_mtime) {
 298                 if (nmstat.st_size)
 299                         newmail();
 300                 getmailstatus();        /* might be too late ... */
 301         }
 302 }
 303
 304 static void
 305 newmail(void)
 306 {
 307         /* produce a scroll of mail */
 308         struct obj *obj;
 309         struct monst *md;
 310         extern struct permonst pm_mail_daemon;
 311
 312         obj = mksobj(SCR_MAIL);
 313         if (md = makemon(&pm_mail_daemon, u.ux, u.uy))  /* always succeeds */
 314                 mdrush(md, 0);
 315
 316         pline("\"Hello, %s! I have some mail for you.\"", plname);
 317         if (md) {
 318                 if (dist(md->mx, md->my) > 2)
 319                         pline("\"Catch!\"");
 320                 more();
 321
 322                 /* let him disappear again */
 323                 mdrush(md, 1);
 324                 mondead(md);
 325         }
 326
 327         obj = addinv(obj);
 328         identify(obj);          /* set known and do prinv() */
 329 }
 330
 331 /* make md run through the cave */
 332 static void
 333 mdrush(struct monst *md, bool away)
 334 {
 335         int uroom = inroom(u.ux, u.uy);
 336
 337         if (uroom >= 0) {
 338                 int tmp = rooms[uroom].fdoor;
 339                 int cnt = rooms[uroom].doorct;
 340                 int fx = u.ux, fy = u.uy;
 341                 while (cnt--) {
 342                         if (dist(fx, fy) < dist(doors[tmp].x, doors[tmp].y)) {
 343                                 fx = doors[tmp].x;
 344                                 fy = doors[tmp].y;
 345                         }
 346                         tmp++;
 347                 }
 348                 tmp_at(-1, md->data->mlet);     /* open call */
 349                 if (away) {     /* interchange origin and destination */
 350                         unpmon(md);
 351                         tmp = fx;
 352                         fx = md->mx;
 353                         md->mx = tmp;
 354                         tmp = fy;
 355                         fy = md->my;
 356                         md->my = tmp;
 357                 }
 358                 while (fx != md->mx || fy != md->my) {
 359                         int dx, dy, nfx = fx, nfy = fy, d1, d2;
 360
 361                         tmp_at(fx, fy);
 362                         d1 = DIST(fx, fy, md->mx, md->my);
 363                         for (dx = -1; dx <= 1; dx++)
 364                                 for (dy = -1; dy <= 1; dy++)
 365                                         if (dx || dy) {
 366                                                 d2 = DIST(fx + dx, fy + dy, md->mx, md->my);
 367                                                 if (d2 < d1) {
 368                                                         d1 = d2;
 369                                                         nfx = fx + dx;
 370                                                         nfy = fy + dy;
 371                                                 }
 372                                         }
 373                         if (nfx != fx || nfy != fy) {
 374                                 fx = nfx;
 375                                 fy = nfy;
 376                         } else {
 377                                 if (!away) {
 378                                         md->mx = fx;
 379                                         md->my = fy;
 380                                 }
 381                                 break;
 382                         }
 383                 }
 384                 tmp_at(-1, -1);         /* close call */
 385         }
 386         if (!away)
 387                 pmon(md);
 388 }
 389
 390 void
 391 readmail(void)
 392 {
 393 #ifdef DEF_MAILREADER           /* This implies that UNIX is defined */
 394         char *mr = NULL;
 395
 396         more();
 397         if (!(mr = getenv("MAILREADER")))
 398                 mr = DEF_MAILREADER;
 399         if (child(1)) {
 400                 execl(mr, mr, NULL);
 401                 exit(1);
 402         }
 403 #else /* DEF_MAILREADER */
 404         page_file(mailbox, FALSE);
 405 #endif /* DEF_MAILREADER */
 406        /* get new stat; not entirely correct: there is a small time
 407         * window where we do not see new mail */
 408         getmailstatus();
 409 }
 410 #endif /* MAIL */
 411
 412 void
 413 regularize(char *s)     /* normalize file name - we don't like ..'s or /'s */
 414 {
 415         char *lp;
 416
 417         while ((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
 418                 *lp = '_';
 419 }