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 /* $DragonFly: src/games/hack/hack.unix.c,v 1.7 2006/08/21 19:45:32 pavalos Exp $ */
   5
   6 /* This file collects some Unix dependencies; hack.pager.c contains some more */
   7
   8 /*
   9  * The time is used for:
  10  *      - seed for random()
  11  *      - year on tombstone and yymmdd in record file
  12  *      - phase of the moon (various monsters react to NEW_MOON or FULL_MOON)
  13  *      - night and midnight (the undead are dangerous at midnight)
  14  *      - determination of what files are "very old"
  15  */
  16
  17 #include <errno.h>
  18 #include "hack.h"
  19
  20 #include <sys/types.h>  /* for time_t and stat */
  21 #include <sys/stat.h>
  22 #include <time.h>
  23
  24 static struct tm *getlt(void);
  25 static bool  veryold(int);
  26 #ifdef MAIL
  27 static void  newmail(void);
  28 static void  mdrush(struct monst *, bool);
  29 #endif
  30
  31 void
  32 setrandom(void)
  33 {
  34         srandomdev();
  35 }
  36
  37 static struct tm *
  38 getlt(void)
  39 {
  40         time_t date;
  41
  42         time(&date);
  43         return (localtime(&date));
  44 }
  45
  46 int
  47 getyear(void)
  48 {
  49         return (1900 + getlt()->tm_year);
  50 }
  51
  52 char *
  53 getdate(void)
  54 {
  55         static char datestr[7];
  56         struct tm *lt = getlt();
  57
  58         snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
  59             lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
  60         return (datestr);
  61 }
  62
  63 int
  64 phase_of_the_moon(void)                 /* 0-7, with 0: new, 4: full */
  65 {                                       /* moon period: 29.5306 days */
  66                                         /* year: 365.2422 days */
  67         struct tm *lt = getlt();
  68         int epact, diy, golden;
  69
  70         diy = lt->tm_yday;
  71         golden = (lt->tm_year % 19) + 1;
  72         epact = (11 * golden + 18) % 30;
  73         if ((epact == 25 && golden > 11) || epact == 24)
  74                 epact++;
  75
  76         return ((((((diy + epact) * 6) + 11) % 177) / 22) & 7);
  77 }
  78
  79 bool
  80 night(void)
  81 {
  82         int hour = getlt()->tm_hour;
  83
  84         return (hour < 6 || hour > 21);
  85 }
  86
  87 bool
  88 midnight(void)
  89 {
  90         return (getlt()->tm_hour == 0);
  91 }
  92
  93 struct stat buf, hbuf;
  94
  95 void
  96 gethdate(const char *name)
  97 {
  98 /* old version - for people short of space */
  99         char *np;
 100
 101         name = "/usr/games/hide/hack";
 102         if (stat(name, &hbuf))
 103                 error("Cannot get status of %s.",
 104                       (np = strrchr(name, '/')) ? np + 1 : name);
 105 }
 106
 107 bool
 108 uptodate(int fd)
 109 {
 110         if (fstat(fd, &buf)) {
 111                 pline("Cannot get status of saved level? ");
 112                 return (0);
 113         }
 114         if (buf.st_mtime < hbuf.st_mtime) {
 115                 pline("Saved level is out of date. ");
 116                 return (0);
 117         }
 118         return (1);
 119 }
 120
 121 /* see whether we should throw away this xlock file */
 122 static bool
 123 veryold(int fd)
 124 {
 125         int i;
 126         time_t date;
 127
 128         if (fstat(fd, &buf))                    /* cannot get status */
 129                 return (0);
 130         if (buf.st_size != sizeof(int))         /* not an xlock file */
 131                 return (0);
 132         time(&date);
 133         if (date - buf.st_mtime < 3L * 24L * 60L * 60L) {       /* recent */
 134                 int lockedpid;  /* should be the same size as hackpid */
 135
 136                 if (read(fd, (char *)&lockedpid, sizeof(lockedpid)) !=
 137                     sizeof(lockedpid))
 138                         /* strange ... */
 139                         return (0);
 140
 141                 /* From: Rick Adams <seismo!rick> */
 142                 /* This will work on 4.1cbsd, 4.2bsd and system 3? & 5. */
 143                 /* It will do nothing on V7 or 4.1bsd. */
 144                 if (!(kill(lockedpid, 0) == -1 && errno == ESRCH))
 145                         return (0);
 146         }
 147         close(fd);
 148         for (i = 1; i <= MAXLEVEL; i++) {       /* try to remove all */
 149                 glo(i);
 150                 unlink(lock);
 151         }
 152         glo(0);
 153         if (unlink(lock))                       /* cannot remove it */
 154                 return (0);
 155         return (1);                             /* success! */
 156 }
 157
 158 void
 159 getlock(void)
 160 {
 161         int i = 0, fd;
 162
 163         fflush(stdout);
 164
 165         /* we ignore QUIT and INT at this point */
 166         if (link(HLOCK, LLOCK) == -1) {
 167                 int errnosv = errno;
 168
 169                 perror(HLOCK);
 170                 printf("Cannot link %s to %s\n", LLOCK, HLOCK);
 171                 switch (errnosv) {
 172                 case ENOENT:
 173                         printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
 174                         break;
 175                 case EACCES:
 176                         printf("It seems you don't have write permission here.\n");
 177                         break;
 178                 case EEXIST:
 179                         printf("(Try again or rm %s.)\n", LLOCK);
 180                         break;
 181                 default:
 182                         printf("I don't know what is wrong.");
 183                 }
 184                 getret();
 185                 error("");
 186                 /* NOTREACHED */
 187         }
 188
 189         regularize(lock);
 190         glo(0);
 191         if (locknum > 25)
 192                 locknum = 25;
 193
 194         do {
 195                 if (locknum)
 196                         lock[0] = 'a' + i++;
 197
 198                 if ((fd = open(lock, O_RDONLY)) == -1) {
 199                         if (errno == ENOENT)    /* no such file */
 200                                 goto gotlock;
 201                         perror(lock);
 202                         unlink(LLOCK);
 203                         error("Cannot open %s", lock);
 204                 }
 205
 206                 if (veryold(fd)) /* if true, this closes fd and unlinks lock */
 207                         goto gotlock;
 208                 close(fd);
 209         } while (i < locknum);
 210
 211         unlink(LLOCK);
 212         error(locknum ? "Too many hacks running now."
 213               : "There is a game in progress under your name.");
 214 gotlock:
 215         fd = creat(lock, FMASK);
 216         if (unlink(LLOCK) == -1)
 217                 error("Cannot unlink %s.", LLOCK);
 218         if (fd == -1) {
 219                 error("cannot creat lock file.");
 220         } else {
 221                 if (write(fd, (char *)&hackpid, sizeof(hackpid))
 222                     != sizeof(hackpid))
 223                         error("cannot write lock");
 224                 if (close(fd) == -1)
 225                         error("cannot close lock");
 226         }
 227 }
 228
 229 #ifdef MAIL
 230
 231 /*
 232  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
 233  * I don't know the details of his implementation.]
 234  * { Later note: he disliked my calling a general mailreader and felt that
 235  *   hack should do the paging itself. But when I get mail, I want to put it
 236  *   in some folder, reply, etc. - it would be unreasonable to put all these
 237  *   functions in hack. }
 238  * The mail daemon '2' is at present not a real monster, but only a visual
 239  * effect. Thus, makemon() is superfluous. This might become otherwise,
 240  * however. The motion of '2' is less restrained than usual: diagonal moves
 241  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
 242  * in a ROOM, even when you are Blind.
 243  * Its path should be longer when you are Telepat-hic and Blind.
 244  *
 245  * Interesting side effects:
 246  *      - You can get rich by sending yourself a lot of mail and selling
 247  *        it to the shopkeeper. Unfortunately mail isn't very valuable.
 248  *      - You might die in case '2' comes along at a critical moment during
 249  *        a fight and delivers a scroll the weight of which causes you to
 250  *        collapse.
 251  *
 252  * Possible extensions:
 253  *      - Open the file MAIL and do fstat instead of stat for efficiency.
 254  *        (But sh uses stat, so this cannot be too bad.)
 255  *      - Examine the mail and produce a scroll of mail called "From somebody".
 256  *      - Invoke MAILREADER in such a way that only this single letter is read.
 257  *
 258  *      - Make him lose his mail when a Nymph steals the letter.
 259  *      - Do something to the text when the scroll is enchanted or cancelled.
 260  */
 261 #include "def.mkroom.h"
 262 static struct stat omstat, nmstat;
 263 static char *mailbox;
 264 static long laststattime;
 265
 266 void
 267 getmailstatus(void)
 268 {
 269         if (!(mailbox = getenv("MAIL")))
 270                 return;
 271         if (stat(mailbox, &omstat)) {
 272 #ifdef PERMANENT_MAILBOX
 273                 pline("Cannot get status of MAIL=%s .", mailbox);
 274                 mailbox = 0;
 275 #else
 276                 omstat.st_mtime = 0;
 277 #endif /* PERMANENT_MAILBOX */
 278         }
 279 }
 280
 281 void
 282 ckmailstatus(void)
 283 {
 284         if (!mailbox
 285 #ifdef MAILCKFREQ
 286             || moves < laststattime + MAILCKFREQ
 287 #endif /* MAILCKFREQ */
 288             )
 289                 return;
 290         laststattime = moves;
 291         if (stat(mailbox, &nmstat)) {
 292 #ifdef PERMANENT_MAILBOX
 293                 pline("Cannot get status of MAIL=%s anymore.", mailbox);
 294                 mailbox = 0;
 295 #else
 296                 nmstat.st_mtime = 0;
 297 #endif /* PERMANENT_MAILBOX */
 298         } else if (nmstat.st_mtime > omstat.st_mtime) {
 299                 if (nmstat.st_size)
 300                         newmail();
 301                 getmailstatus();        /* might be too late ... */
 302         }
 303 }
 304
 305 static void
 306 newmail(void)
 307 {
 308         /* produce a scroll of mail */
 309         struct obj *obj;
 310         struct monst *md;
 311         extern struct permonst pm_mail_daemon;
 312
 313         obj = mksobj(SCR_MAIL);
 314         if (md = makemon(&pm_mail_daemon, u.ux, u.uy))  /* always succeeds */
 315                 mdrush(md, 0);
 316
 317         pline("\"Hello, %s! I have some mail for you.\"", plname);
 318         if (md) {
 319                 if (dist(md->mx, md->my) > 2)
 320                         pline("\"Catch!\"");
 321                 more();
 322
 323                 /* let him disappear again */
 324                 mdrush(md, 1);
 325                 mondead(md);
 326         }
 327
 328         obj = addinv(obj);
 329         identify(obj);          /* set known and do prinv() */
 330 }
 331
 332 /* make md run through the cave */
 333 static void
 334 mdrush(struct monst *md, bool away)
 335 {
 336         int uroom = inroom(u.ux, u.uy);
 337
 338         if (uroom >= 0) {
 339                 int tmp = rooms[uroom].fdoor;
 340                 int cnt = rooms[uroom].doorct;
 341                 int fx = u.ux, fy = u.uy;
 342                 while (cnt--) {
 343                         if (dist(fx, fy) < dist(doors[tmp].x, doors[tmp].y)) {
 344                                 fx = doors[tmp].x;
 345                                 fy = doors[tmp].y;
 346                         }
 347                         tmp++;
 348                 }
 349                 tmp_at(-1, md->data->mlet);     /* open call */
 350                 if (away) {     /* interchange origin and destination */
 351                         unpmon(md);
 352                         tmp = fx;
 353                         fx = md->mx;
 354                         md->mx = tmp;
 355                         tmp = fy;
 356                         fy = md->my;
 357                         md->my = tmp;
 358                 }
 359                 while (fx != md->mx || fy != md->my) {
 360                         int dx, dy, nfx = fx, nfy = fy, d1, d2;
 361
 362                         tmp_at(fx, fy);
 363                         d1 = DIST(fx, fy, md->mx, md->my);
 364                         for (dx = -1; dx <= 1; dx++)
 365                                 for (dy = -1; dy <= 1; dy++)
 366                                         if (dx || dy) {
 367                                                 d2 = DIST(fx + dx, fy + dy, md->mx, md->my);
 368                                                 if (d2 < d1) {
 369                                                         d1 = d2;
 370                                                         nfx = fx + dx;
 371                                                         nfy = fy + dy;
 372                                                 }
 373                                         }
 374                         if (nfx != fx || nfy != fy) {
 375                                 fx = nfx;
 376                                 fy = nfy;
 377                         } else {
 378                                 if (!away) {
 379                                         md->mx = fx;
 380                                         md->my = fy;
 381                                 }
 382                                 break;
 383                         }
 384                 }
 385                 tmp_at(-1, -1);         /* close call */
 386         }
 387         if (!away)
 388                 pmon(md);
 389 }
 390
 391 void
 392 readmail(void)
 393 {
 394 #ifdef DEF_MAILREADER           /* This implies that UNIX is defined */
 395         char *mr = 0;
 396
 397         more();
 398         if (!(mr = getenv("MAILREADER")))
 399                 mr = DEF_MAILREADER;
 400         if (child(1)) {
 401                 execl(mr, mr, NULL);
 402                 exit(1);
 403         }
 404 #else /* DEF_MAILREADER */
 405         page_file(mailbox, FALSE);
 406 #endif /* DEF_MAILREADER */
 407        /* get new stat; not entirely correct: there is a small time
 408         * window where we do not see new mail */
 409         getmailstatus();
 410 }
 411 #endif /* MAIL */
 412
 413 void
 414 regularize(char *s)     /* normalize file name - we don't like ..'s or /'s */
 415 {
 416         char *lp;
 417
 418         while ((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
 419                 *lp = '_';
 420 }