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 <err.h>
  22 #include <limits.h>
  23 #include <time.h>
  24
  25 static struct tm *getlt(void);
  26 static bool  veryold(int);
  27 #ifdef MAIL
  28 static void  newmail(void);
  29 static void  mdrush(struct monst *, bool);
  30 #endif
  31
  32 void
  33 setrandom(void)
  34 {
  35         srandomdev();
  36 }
  37
  38 static struct tm *
  39 getlt(void)
  40 {
  41         time_t date;
  42
  43         time(&date);
  44         return (localtime(&date));
  45 }
  46
  47 int
  48 getyear(void)
  49 {
  50         return (1900 + getlt()->tm_year);
  51 }
  52
  53 char *
  54 getdate(void)
  55 {
  56         static char datestr[7];
  57         struct tm *lt = getlt();
  58
  59         snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
  60             lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
  61         return (datestr);
  62 }
  63
  64 int
  65 phase_of_the_moon(void)                 /* 0-7, with 0: new, 4: full */
  66 {                                       /* moon period: 29.5306 days */
  67                                         /* year: 365.2422 days */
  68         struct tm *lt = getlt();
  69         int epact, diy, golden;
  70
  71         diy = lt->tm_yday;
  72         golden = (lt->tm_year % 19) + 1;
  73         epact = (11 * golden + 18) % 30;
  74         if ((epact == 25 && golden > 11) || epact == 24)
  75                 epact++;
  76
  77         return ((((((diy + epact) * 6) + 11) % 177) / 22) & 7);
  78 }
  79
  80 bool
  81 night(void)
  82 {
  83         int hour = getlt()->tm_hour;
  84
  85         return (hour < 6 || hour > 21);
  86 }
  87
  88 bool
  89 midnight(void)
  90 {
  91         return (getlt()->tm_hour == 0);
  92 }
  93
  94 struct stat buf, hbuf;
  95
  96 void
  97 gethdate(const char *name)
  98 {
  99         const char *p;
 100         char *np, *path;
 101         char filename[PATH_MAX+1];
 102
 103         if (strchr(name, '/') != NULL || (p = getenv("PATH")) == NULL)
 104                 p = "";
 105         np = path = strdup(p);  /* Make a copy for strsep. */
 106         if (path == NULL)
 107                 err(1, NULL);
 108
 109         for (;;) {
 110                 if ((p = strsep(&np, ":")) == NULL)
 111                         break;
 112                 if (*p == '\0')                 /* :: */
 113                         strlcpy(filename, name, sizeof filename);
 114                 else
 115                         snprintf(filename, sizeof filename, "%s/%s", p, name);
 116
 117                 if (stat(filename, &hbuf) == 0) {
 118                         free(path);
 119                         return;
 120                 }
 121         }
 122         error("Cannot get status of %s.",
 123                 (p = strrchr(name, '/')) ? p+1 : name);
 124         free(path);
 125 }
 126
 127 bool
 128 uptodate(int fd)
 129 {
 130         if (fstat(fd, &buf)) {
 131                 pline("Cannot get status of saved level? ");
 132                 return (0);
 133         }
 134         if (buf.st_mtime < hbuf.st_mtime) {
 135                 pline("Saved level is out of date. ");
 136                 return (0);
 137         }
 138         return (1);
 139 }
 140
 141 /* see whether we should throw away this xlock file */
 142 static bool
 143 veryold(int fd)
 144 {
 145         int i;
 146         time_t date;
 147
 148         if (fstat(fd, &buf))                    /* cannot get status */
 149                 return (0);
 150         if (buf.st_size != sizeof(int))         /* not an xlock file */
 151                 return (0);
 152         time(&date);
 153         if (date - buf.st_mtime < 3L * 24L * 60L * 60L) {       /* recent */
 154                 int lockedpid;  /* should be the same size as hackpid */
 155
 156                 if (read(fd, (char *)&lockedpid, sizeof(lockedpid)) !=
 157                     sizeof(lockedpid))
 158                         /* strange ... */
 159                         return (0);
 160
 161                 /* From: Rick Adams <seismo!rick> */
 162                 /* This will work on 4.1cbsd, 4.2bsd and system 3? & 5. */
 163                 /* It will do nothing on V7 or 4.1bsd. */
 164                 if (!(kill(lockedpid, 0) == -1 && errno == ESRCH))
 165                         return (0);
 166         }
 167         close(fd);
 168         for (i = 1; i <= MAXLEVEL; i++) {       /* try to remove all */
 169                 glo(i);
 170                 unlink(lock);
 171         }
 172         glo(0);
 173         if (unlink(lock))                       /* cannot remove it */
 174                 return (0);
 175         return (1);                             /* success! */
 176 }
 177
 178 void
 179 getlock(void)
 180 {
 181         int i = 0, fd;
 182
 183         fflush(stdout);
 184
 185         /* we ignore QUIT and INT at this point */
 186         if ((link(HLOCK, LLOCK) == -1) && (symlink(HLOCK, LLOCK) == -1)) {
 187                 int errnosv = errno;
 188
 189                 perror(HLOCK);
 190                 printf("Cannot link %s to %s\n", LLOCK, HLOCK);
 191                 switch (errnosv) {
 192                 case ENOENT:
 193                         printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
 194                         break;
 195                 case EACCES:
 196                         printf("It seems you don't have write permission here.\n");
 197                         break;
 198                 case EEXIST:
 199                         printf("(Try again or rm %s.)\n", LLOCK);
 200                         break;
 201                 default:
 202                         printf("I don't know what is wrong.");
 203                 }
 204                 getret();
 205                 error("%s", "");
 206                 /* NOTREACHED */
 207         }
 208
 209         regularize(lock);
 210         glo(0);
 211         if (locknum > 25)
 212                 locknum = 25;
 213
 214         do {
 215                 if (locknum)
 216                         lock[0] = 'a' + i++;
 217
 218                 if ((fd = open(lock, O_RDONLY)) == -1) {
 219                         if (errno == ENOENT)    /* no such file */
 220                                 goto gotlock;
 221                         perror(lock);
 222                         unlink(LLOCK);
 223                         error("Cannot open %s", lock);
 224                 }
 225
 226                 if (veryold(fd)) /* if true, this closes fd and unlinks lock */
 227                         goto gotlock;
 228                 close(fd);
 229         } while (i < locknum);
 230
 231         unlink(LLOCK);
 232         error(locknum ? "Too many hacks running now."
 233               : "There is a game in progress under your name.");
 234 gotlock:
 235         fd = creat(lock, FMASK);
 236         if (unlink(LLOCK) == -1)
 237                 error("Cannot unlink %s.", LLOCK);
 238         if (fd == -1) {
 239                 error("cannot creat lock file.");
 240         } else {
 241                 if (write(fd, (char *)&hackpid, sizeof(hackpid))
 242                     != sizeof(hackpid))
 243                         error("cannot write lock");
 244                 if (close(fd) == -1)
 245                         error("cannot close lock");
 246         }
 247 }
 248
 249 #ifdef MAIL
 250
 251 /*
 252  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
 253  * I don't know the details of his implementation.]
 254  * { Later note: he disliked my calling a general mailreader and felt that
 255  *   hack should do the paging itself. But when I get mail, I want to put it
 256  *   in some folder, reply, etc. - it would be unreasonable to put all these
 257  *   functions in hack. }
 258  * The mail daemon '2' is at present not a real monster, but only a visual
 259  * effect. Thus, makemon() is superfluous. This might become otherwise,
 260  * however. The motion of '2' is less restrained than usual: diagonal moves
 261  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
 262  * in a ROOM, even when you are Blind.
 263  * Its path should be longer when you are Telepat-hic and Blind.
 264  *
 265  * Interesting side effects:
 266  *      - You can get rich by sending yourself a lot of mail and selling
 267  *        it to the shopkeeper. Unfortunately mail isn't very valuable.
 268  *      - You might die in case '2' comes along at a critical moment during
 269  *        a fight and delivers a scroll the weight of which causes you to
 270  *        collapse.
 271  *
 272  * Possible extensions:
 273  *      - Open the file MAIL and do fstat instead of stat for efficiency.
 274  *        (But sh uses stat, so this cannot be too bad.)
 275  *      - Examine the mail and produce a scroll of mail called "From somebody".
 276  *      - Invoke MAILREADER in such a way that only this single letter is read.
 277  *
 278  *      - Make him lose his mail when a Nymph steals the letter.
 279  *      - Do something to the text when the scroll is enchanted or cancelled.
 280  */
 281 #include "def.mkroom.h"
 282 static struct stat omstat, nmstat;
 283 static char *mailbox;
 284 static long laststattime;
 285
 286 void
 287 getmailstatus(void)
 288 {
 289         if (!(mailbox = getenv("MAIL")))
 290                 return;
 291         if (stat(mailbox, &omstat)) {
 292 #ifdef PERMANENT_MAILBOX
 293                 pline("Cannot get status of MAIL=%s .", mailbox);
 294                 mailbox = NULL;
 295 #else
 296                 omstat.st_mtime = 0;
 297 #endif /* PERMANENT_MAILBOX */
 298         }
 299 }
 300
 301 void
 302 ckmailstatus(void)
 303 {
 304         if (!mailbox
 305 #ifdef MAILCKFREQ
 306             || moves < laststattime + MAILCKFREQ
 307 #endif /* MAILCKFREQ */
 308             )
 309                 return;
 310         laststattime = moves;
 311         if (stat(mailbox, &nmstat)) {
 312 #ifdef PERMANENT_MAILBOX
 313                 pline("Cannot get status of MAIL=%s anymore.", mailbox);
 314                 mailbox = NULL;
 315 #else
 316                 nmstat.st_mtime = 0;
 317 #endif /* PERMANENT_MAILBOX */
 318         } else if (nmstat.st_mtime > omstat.st_mtime) {
 319                 if (nmstat.st_size)
 320                         newmail();
 321                 getmailstatus();        /* might be too late ... */
 322         }
 323 }
 324
 325 static void
 326 newmail(void)
 327 {
 328         /* produce a scroll of mail */
 329         struct obj *obj;
 330         struct monst *md;
 331         extern struct permonst pm_mail_daemon;
 332
 333         obj = mksobj(SCR_MAIL);
 334         if (md = makemon(&pm_mail_daemon, u.ux, u.uy))  /* always succeeds */
 335                 mdrush(md, 0);
 336
 337         pline("\"Hello, %s! I have some mail for you.\"", plname);
 338         if (md) {
 339                 if (dist(md->mx, md->my) > 2)
 340                         pline("\"Catch!\"");
 341                 more();
 342
 343                 /* let him disappear again */
 344                 mdrush(md, 1);
 345                 mondead(md);
 346         }
 347
 348         obj = addinv(obj);
 349         identify(obj);          /* set known and do prinv() */
 350 }
 351
 352 /* make md run through the cave */
 353 static void
 354 mdrush(struct monst *md, bool away)
 355 {
 356         int uroom = inroom(u.ux, u.uy);
 357
 358         if (uroom >= 0) {
 359                 int tmp = rooms[uroom].fdoor;
 360                 int cnt = rooms[uroom].doorct;
 361                 int fx = u.ux, fy = u.uy;
 362                 while (cnt--) {
 363                         if (dist(fx, fy) < dist(doors[tmp].x, doors[tmp].y)) {
 364                                 fx = doors[tmp].x;
 365                                 fy = doors[tmp].y;
 366                         }
 367                         tmp++;
 368                 }
 369                 tmp_at(-1, md->data->mlet);     /* open call */
 370                 if (away) {     /* interchange origin and destination */
 371                         unpmon(md);
 372                         tmp = fx;
 373                         fx = md->mx;
 374                         md->mx = tmp;
 375                         tmp = fy;
 376                         fy = md->my;
 377                         md->my = tmp;
 378                 }
 379                 while (fx != md->mx || fy != md->my) {
 380                         int dx, dy, nfx = fx, nfy = fy, d1, d2;
 381
 382                         tmp_at(fx, fy);
 383                         d1 = DIST(fx, fy, md->mx, md->my);
 384                         for (dx = -1; dx <= 1; dx++)
 385                                 for (dy = -1; dy <= 1; dy++)
 386                                         if (dx || dy) {
 387                                                 d2 = DIST(fx + dx, fy + dy, md->mx, md->my);
 388                                                 if (d2 < d1) {
 389                                                         d1 = d2;
 390                                                         nfx = fx + dx;
 391                                                         nfy = fy + dy;
 392                                                 }
 393                                         }
 394                         if (nfx != fx || nfy != fy) {
 395                                 fx = nfx;
 396                                 fy = nfy;
 397                         } else {
 398                                 if (!away) {
 399                                         md->mx = fx;
 400                                         md->my = fy;
 401                                 }
 402                                 break;
 403                         }
 404                 }
 405                 tmp_at(-1, -1);         /* close call */
 406         }
 407         if (!away)
 408                 pmon(md);
 409 }
 410
 411 void
 412 readmail(void)
 413 {
 414 #ifdef DEF_MAILREADER           /* This implies that UNIX is defined */
 415         char *mr = NULL;
 416
 417         more();
 418         if (!(mr = getenv("MAILREADER")))
 419                 mr = DEF_MAILREADER;
 420         if (child(1)) {
 421                 execl(mr, mr, NULL);
 422                 exit(1);
 423         }
 424 #else /* DEF_MAILREADER */
 425         page_file(mailbox, FALSE);
 426 #endif /* DEF_MAILREADER */
 427        /* get new stat; not entirely correct: there is a small time
 428         * window where we do not see new mail */
 429         getmailstatus();
 430 }
 431 #endif /* MAIL */
 432
 433 void
 434 regularize(char *s)     /* normalize file name - we don't like ..'s or /'s */
 435 {
 436         char *lp;
 437
 438         while ((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
 439                 *lp = '_';
 440 }