xref: /dragonfly/games/hack/hack.unix.c (revision d5d36918)
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 /* This file collects some Unix dependencies; hack.pager.c contains some more */
65 
66 /*
67  * The time is used for:
68  *	- seed for random()
69  *	- year on tombstone and yymmdd in record file
70  *	- phase of the moon (various monsters react to NEW_MOON or FULL_MOON)
71  *	- night and midnight (the undead are dangerous at midnight)
72  *	- determination of what files are "very old"
73  */
74 
75 #include <errno.h>
76 #include <sys/types.h>	/* for time_t and stat */
77 #include <sys/stat.h>
78 #ifdef BSD
79 #include <sys/time.h>
80 #else
81 #include <time.h>
82 #endif	/* BSD */
83 #include <stdlib.h>
84 #include <unistd.h>
85 #include <signal.h>
86 #include <fcntl.h>
87 
88 #include "hack.h"		/* mainly for strchr() which depends on BSD */
89 #include "extern.h"
90 
91 extern int locknum;
92 
93 static struct tm *getlt(void);
94 static int veryold(int);
95 
96 
97 void
98 setrandom(void)
99 {
100 	(void) srandom((int) time((time_t *) 0));
101 }
102 
103 static struct tm *
104 getlt(void)
105 {
106 	time_t          date;
107 
108 	(void) time(&date);
109 	return (localtime(&date));
110 }
111 
112 int
113 getyear(void)
114 {
115 	return (1900 + getlt()->tm_year);
116 }
117 
118 char           *
119 getdatestr(void)
120 {
121 	static char     datestr[32];
122 	struct tm      *lt = getlt();
123 
124 	(void) snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
125 		       lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
126 	return (datestr);
127 }
128 
129 int
130 phase_of_the_moon(void)
131 {				/* 0-7, with 0: new, 4: full *//* moon
132 				 * period: 29.5306 days */
133 	/* year: 365.2422 days */
134 	struct tm      *lt = getlt();
135 	int             epact, diy, golden;
136 
137 	diy = lt->tm_yday;
138 	golden = (lt->tm_year % 19) + 1;
139 	epact = (11 * golden + 18) % 30;
140 	if ((epact == 25 && golden > 11) || epact == 24)
141 		epact++;
142 
143 	return ((((((diy + epact) * 6) + 11) % 177) / 22) & 7);
144 }
145 
146 int
147 night(void)
148 {
149 	int             hour = getlt()->tm_hour;
150 
151 	return (hour < 6 || hour > 21);
152 }
153 
154 int
155 midnight(void)
156 {
157 	return (getlt()->tm_hour == 0);
158 }
159 
160 static struct stat buf, hbuf;
161 
162 void
163 gethdate(char *name)
164 {
165 #if 0
166 	/* old version - for people short of space */
167 
168 	char *np;
169 
170 	if(stat(name, &hbuf))
171 	    error("Cannot get status of %s.",
172 		(np = strrchr(name, '/')) ? np+1 : name);
173 #else
174 	/* version using PATH from: seismo!gregc@ucsf-cgl.ARPA (Greg Couch) */
175 
176 
177 	/*
178 	 * The problem with   #include	<sys/param.h>   is that this include file
179 	 * does not exist on all systems, and moreover, that it sometimes includes
180 	 * <sys/types.h> again, so that the compiler sees these typedefs twice.
181 	 */
182 #define		MAXPATHLEN	1024
183 
184 	const char           *np, *path;
185 	char            filename[MAXPATHLEN + 1];
186 	if (strchr(name, '/') != NULL || (path = getenv("PATH")) == NULL)
187 		path = "";
188 
189 	for (;;) {
190 		if ((np = strchr(path, ':')) == NULL)
191 			np = path + strlen(path);	/* point to end str */
192 		if (np - path <= 1)	/* %% */
193 			(void) strlcpy(filename, name, sizeof(filename));
194 		else {
195 			(void) snprintf(filename, sizeof(filename),
196 				"%.*s/%s",
197 				(int)(np - path), path, name);
198 		}
199 		if (stat(filename, &hbuf) == 0)
200 			return;
201 		if (*np == '\0')
202 			break;
203 		path = np + 1;
204 	}
205 	error("Cannot get status of %s.",
206 	      (np = strrchr(name, '/')) ? np + 1 : name);
207 #endif
208 }
209 
210 int
211 uptodate(int fd)
212 {
213 	if (fstat(fd, &buf)) {
214 		pline("Cannot get status of saved level? ");
215 		return (0);
216 	}
217 	if (buf.st_mtime < hbuf.st_mtime) {
218 		pline("Saved level is out of date. ");
219 		return (0);
220 	}
221 	return (1);
222 }
223 
224 /* see whether we should throw away this xlock file */
225 static int
226 veryold(int fd)
227 {
228 	int             i;
229 	time_t          date;
230 
231 	if (fstat(fd, &buf))
232 		return (0);	/* cannot get status */
233 	if (buf.st_size != sizeof(int))
234 		return (0);	/* not an xlock file */
235 	(void) time(&date);
236 	if (date - buf.st_mtime < 3L * 24L * 60L * 60L) {	/* recent */
237 		int             lockedpid;	/* should be the same size as
238 						 * hackpid */
239 
240 		if (read(fd, &lockedpid, sizeof(lockedpid)) !=
241 		    sizeof(lockedpid))
242 			/* strange ... */
243 			return (0);
244 
245 		/*
246 		 * From: Rick Adams <seismo!rick> This will work on
247 		 * 4.1cbsd, 4.2bsd and system 3? & 5. It will do nothing
248 		 * on V7 or 4.1bsd.
249 		 */
250 		if (!(kill(lockedpid, 0) == -1 && errno == ESRCH))
251 			return (0);
252 	}
253 	(void) close(fd);
254 	for (i = 1; i <= MAXLEVEL; i++) {	/* try to remove all */
255 		glo(i);
256 		(void) unlink(lock);
257 	}
258 	glo(0);
259 	if (unlink(lock))
260 		return (0);	/* cannot remove it */
261 	return (1);		/* success! */
262 }
263 
264 void
265 getlock(void)
266 {
267 	int             i = 0, fd;
268 
269 	(void) fflush(stdout);
270 
271 	/* we ignore QUIT and INT at this point */
272 	if (link(HLOCK, LLOCK) == -1) {
273 		int             errnosv = errno;
274 
275 		perror(HLOCK);
276 		printf("Cannot link %s to %s\n", LLOCK, HLOCK);
277 		switch (errnosv) {
278 		case ENOENT:
279 			printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
280 			break;
281 		case EACCES:
282 			printf("It seems you don't have write permission here.\n");
283 			break;
284 		case EEXIST:
285 			printf("(Try again or rm %s.)\n", LLOCK);
286 			break;
287 		default:
288 			printf("I don't know what is wrong.");
289 		}
290 		getret();
291 		error("%s", "");
292 		/* NOTREACHED */
293 	}
294 	regularize(lock);
295 	glo(0);
296 	if (locknum > 25)
297 		locknum = 25;
298 
299 	do {
300 		if (locknum)
301 			lock[0] = 'a' + i++;
302 
303 		if ((fd = open(lock, O_RDONLY)) == -1) {
304 			if (errno == ENOENT)
305 				goto gotlock;	/* no such file */
306 			perror(lock);
307 			(void) unlink(LLOCK);
308 			error("Cannot open %s", lock);
309 		}
310 		if (veryold(fd))/* if true, this closes fd and unlinks lock */
311 			goto gotlock;
312 		(void) close(fd);
313 	} while (i < locknum);
314 
315 	(void) unlink(LLOCK);
316 	error(locknum ? "Too many hacks running now."
317 	      : "There is a game in progress under your name.");
318 gotlock:
319 	fd = creat(lock, FMASK);
320 	if (unlink(LLOCK) == -1)
321 		error("Cannot unlink %s.", LLOCK);
322 	if (fd == -1) {
323 		error("cannot creat lock file.");
324 	} else {
325 		if (write(fd, &hackpid, sizeof(hackpid))
326 		    != sizeof(hackpid)) {
327 			error("cannot write lock");
328 		}
329 		if (close(fd) == -1) {
330 			error("cannot close lock");
331 		}
332 	}
333 }
334 
335 #ifdef MAIL
336 
337 /*
338  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
339  * I don't know the details of his implementation.]
340  * { Later note: he disliked my calling a general mailreader and felt that
341  *   hack should do the paging itself. But when I get mail, I want to put it
342  *   in some folder, reply, etc. - it would be unreasonable to put all these
343  *   functions in hack. }
344  * The mail daemon '2' is at present not a real monster, but only a visual
345  * effect. Thus, makemon() is superfluous. This might become otherwise,
346  * however. The motion of '2' is less restrained than usual: diagonal moves
347  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
348  * in a ROOM, even when you are Blind.
349  * Its path should be longer when you are Telepat-hic and Blind.
350  *
351  * Interesting side effects:
352  *	- You can get rich by sending yourself a lot of mail and selling
353  *	  it to the shopkeeper. Unfortunately mail isn't very valuable.
354  *	- You might die in case '2' comes along at a critical moment during
355  *	  a fight and delivers a scroll the weight of which causes you to
356  *	  collapse.
357  *
358  * Possible extensions:
359  *	- Open the file MAIL and do fstat instead of stat for efficiency.
360  *	  (But sh uses stat, so this cannot be too bad.)
361  *	- Examine the mail and produce a scroll of mail called "From somebody".
362  *	- Invoke MAILREADER in such a way that only this single letter is read.
363  *
364  *	- Make him lose his mail when a Nymph steals the letter.
365  *	- Do something to the text when the scroll is enchanted or cancelled.
366  */
367 #include	"def.mkroom.h"
368 static struct stat omstat, nmstat;
369 static char    *mailbox;
370 static long     laststattime;
371 
372 void
373 getmailstatus(void)
374 {
375 	if (!(mailbox = getenv("MAIL")))
376 		return;
377 	if (stat(mailbox, &omstat)) {
378 #ifdef PERMANENT_MAILBOX
379 		pline("Cannot get status of MAIL=%s .", mailbox);
380 		mailbox = 0;
381 #else
382 		omstat.st_mtime = 0;
383 #endif	/* PERMANENT_MAILBOX */
384 	}
385 }
386 
387 void
388 ckmailstatus(void)
389 {
390 	if (!mailbox
391 #ifdef MAILCKFREQ
392 	    || moves < laststattime + MAILCKFREQ
393 #endif	/* MAILCKFREQ */
394 		)
395 		return;
396 	laststattime = moves;
397 	if (stat(mailbox, &nmstat)) {
398 #ifdef PERMANENT_MAILBOX
399 		pline("Cannot get status of MAIL=%s anymore.", mailbox);
400 		mailbox = 0;
401 #else
402 		nmstat.st_mtime = 0;
403 #endif	/* PERMANENT_MAILBOX */
404 	} else if (nmstat.st_mtime > omstat.st_mtime) {
405 		if (nmstat.st_size)
406 			newmail();
407 		getmailstatus();/* might be too late ... */
408 	}
409 }
410 
411 void
412 newmail(void)
413 {
414 	/* produce a scroll of mail */
415 	struct obj     *obj;
416 	struct monst   *md;
417 
418 	obj = mksobj(SCR_MAIL);
419 	if (md = makemon(&pm_mail_daemon, u.ux, u.uy))	/* always succeeds */
420 		mdrush(md, 0);
421 
422 	pline("\"Hello, %s! I have some mail for you.\"", plname);
423 	if (md) {
424 		if (dist(md->mx, md->my) > 2)
425 			pline("\"Catch!\"");
426 		more();
427 
428 		/* let him disappear again */
429 		mdrush(md, 1);
430 		mondead(md);
431 	}
432 	obj = addinv(obj);
433 	(void) identify(obj);	/* set known and do prinv() */
434 }
435 
436 /* make md run through the cave */
437 void
438 mdrush(struct monst *md, boolean away)
439 {
440 	int             uroom = inroom(u.ux, u.uy);
441 	if (uroom >= 0) {
442 		int             tmp = rooms[uroom].fdoor;
443 		int             cnt = rooms[uroom].doorct;
444 		int             fx = u.ux, fy = u.uy;
445 		while (cnt--) {
446 			if (dist(fx, fy) < dist(doors[tmp].x, doors[tmp].y)) {
447 				fx = doors[tmp].x;
448 				fy = doors[tmp].y;
449 			}
450 			tmp++;
451 		}
452 		tmp_at(-1, md->data->mlet);	/* open call */
453 		if (away) {	/* interchange origin and destination */
454 			unpmon(md);
455 			tmp = fx;
456 			fx = md->mx;
457 			md->mx = tmp;
458 			tmp = fy;
459 			fy = md->my;
460 			md->my = tmp;
461 		}
462 		while (fx != md->mx || fy != md->my) {
463 			int             dx, dy, nfx = fx, nfy = fy, d1,
464 			                d2;
465 
466 			tmp_at(fx, fy);
467 			d1 = DIST(fx, fy, md->mx, md->my);
468 			for (dx = -1; dx <= 1; dx++)
469 				for (dy = -1; dy <= 1; dy++)
470 					if (dx || dy) {
471 						d2 = DIST(fx + dx, fy + dy, md->mx, md->my);
472 						if (d2 < d1) {
473 							d1 = d2;
474 							nfx = fx + dx;
475 							nfy = fy + dy;
476 						}
477 					}
478 			if (nfx != fx || nfy != fy) {
479 				fx = nfx;
480 				fy = nfy;
481 			} else {
482 				if (!away) {
483 					md->mx = fx;
484 					md->my = fy;
485 				}
486 				break;
487 			}
488 		}
489 		tmp_at(-1, -1);	/* close call */
490 	}
491 	if (!away)
492 		pmon(md);
493 }
494 
495 void
496 readmail(void)
497 {
498 #ifdef DEF_MAILREADER		/* This implies that UNIX is defined */
499 	char           *mr = 0;
500 	more();
501 	if (!(mr = getenv("MAILREADER")))
502 		mr = DEF_MAILREADER;
503 	if (child(1)) {
504 		execl(mr, mr, (char *)NULL);
505 		exit(1);
506 	}
507 #else	/* DEF_MAILREADER */
508 	(void) page_file(mailbox, FALSE);
509 #endif	/* DEF_MAILREADER */
510 	/*
511 	 * get new stat; not entirely correct: there is a small time window
512 	 * where we do not see new mail
513 	 */
514 	getmailstatus();
515 }
516 #endif	/* MAIL */
517 
518 /*
519  * normalize file name - we don't like ..'s or /'s
520  */
521 void
522 regularize(char *s)
523 {
524 	char           *lp;
525 
526 	while ((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
527 		*lp = '_';
528 }
529