xref: /openbsd/games/hack/hack.unix.c (revision 404b540a)
1 /*	$OpenBSD: hack.unix.c,v 1.13 2003/05/19 06:30:56 pjanzen 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 #ifndef lint
65 static const char rcsid[] = "$OpenBSD: hack.unix.c,v 1.13 2003/05/19 06:30:56 pjanzen Exp $";
66 #endif /* not lint */
67 
68 /* This file collects some Unix dependencies; hack.pager.c contains some more */
69 
70 /*
71  * The time is used for:
72  *	- seed for random()
73  *	- year on tombstone and yymmdd in record file
74  *	- phase of the moon (various monsters react to NEW_MOON or FULL_MOON)
75  *	- night and midnight (the undead are dangerous at midnight)
76  *	- determination of what files are "very old"
77  */
78 
79 #include	<sys/types.h>		/* for time_t and stat */
80 #include	<sys/stat.h>
81 #include	<sys/param.h>
82 #include	<sys/time.h>
83 
84 #include	<err.h>
85 #include	<errno.h>
86 #include	<signal.h>
87 #include	<stdio.h>
88 #include	<stdlib.h>
89 #include	<unistd.h>
90 #include	"hack.h"
91 
92 
93 static struct tm *getlt(void);
94 static int veryold(int);
95 #ifdef MAIL
96 static void newmail(void);
97 static void mdrush(struct monst *, boolean);
98 #endif
99 
100 static struct tm *
101 getlt()
102 {
103 	time_t date;
104 	struct tm *localtime();
105 
106 	(void) time(&date);
107 	return(localtime(&date));
108 }
109 
110 int
111 getyear()
112 {
113 	return(1900 + getlt()->tm_year);
114 }
115 
116 char *
117 getdate()
118 {
119 	static char datestr[7];
120 	struct tm *lt = getlt();
121 
122 	(void) snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
123 		lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
124 	return(datestr);
125 }
126 
127 int
128 phase_of_the_moon()			/* 0-7, with 0: new, 4: full */
129 {					/* moon period: 29.5306 days */
130 					/* year: 365.2422 days */
131 	struct tm *lt = getlt();
132 	int epact, diy, golden;
133 
134 	diy = lt->tm_yday;
135 	golden = (lt->tm_year % 19) + 1;
136 	epact = (11 * golden + 18) % 30;
137 	if ((epact == 25 && golden > 11) || epact == 24)
138 		epact++;
139 
140 	return( (((((diy + epact) * 6) + 11) % 177) / 22) & 7 );
141 }
142 
143 int
144 night()
145 {
146 	int hour = getlt()->tm_hour;
147 
148 	return(hour < 6 || hour > 21);
149 }
150 
151 int
152 midnight()
153 {
154 	return(getlt()->tm_hour == 0);
155 }
156 
157 struct stat buf, hbuf;
158 
159 void
160 gethdate(char *name)
161 {
162 	char *p, *np, *path;
163 	char filename[MAXPATHLEN+1];
164 
165 	if (strchr(name, '/') != NULL || (p = getenv("PATH")) == NULL)
166 		p = "";
167 	np = path = strdup(p);	/* Make a copy for strsep. */
168 	if (path == NULL)
169 		err(1, NULL);
170 
171 	for (;;) {
172 		if ((p = strsep(&np, ":")) == NULL)
173 			break;
174 		if (*p == '\0')			/* :: */
175 			(void) strlcpy(filename, name, sizeof filename);
176 		else
177 			(void) snprintf(filename, sizeof filename,
178 			    "%s/%s", p, name);
179 
180 		if (stat(filename, &hbuf) == 0) {
181 			free(path);
182 			return;
183 		}
184 	}
185 	error("Cannot get status of %s.",
186 		(p = strrchr(name, '/')) ? p+1 : name);
187 	free(path);
188 }
189 
190 int
191 uptodate(int fd)
192 {
193 	if(fstat(fd, &buf)) {
194 		pline("Cannot get status of saved level? ");
195 		return(0);
196 	}
197 	if(buf.st_mtime < hbuf.st_mtime) {
198 		pline("Saved level is out of date. ");
199 		return(0);
200 	}
201 	return(1);
202 }
203 
204 /* see whether we should throw away this xlock file */
205 static int
206 veryold(int fd)
207 {
208 	int i;
209 	time_t date;
210 
211 	if(fstat(fd, &buf)) return(0);			/* cannot get status */
212 	if(buf.st_size != sizeof(int)) return(0);	/* not an xlock file */
213 	(void) time(&date);
214 	if(date - buf.st_mtime < 3L*24L*60L*60L) {	/* recent */
215 		int lockedpid;	/* should be the same size as hackpid */
216 
217 		if(read(fd, (char *)&lockedpid, sizeof(lockedpid)) !=
218 			sizeof(lockedpid))
219 			/* strange ... */
220 			return(0);
221 
222 		/* From: Rick Adams <seismo!rick>
223 		   This will work on 4.1cbsd, 4.2bsd and system 3? & 5.
224 		   It will do nothing on V7 or 4.1bsd. */
225 		if(!(kill(lockedpid, 0) == -1 && errno == ESRCH))
226 			return(0);
227 	}
228 	(void) close(fd);
229 	for(i = 1; i <= MAXLEVEL; i++) {		/* try to remove all */
230 		glo(i);
231 		(void) unlink(lock);
232 	}
233 	glo(0);
234 	if(unlink(lock)) return(0);			/* cannot remove it */
235 	return(1);					/* success! */
236 }
237 
238 void
239 getlock()
240 {
241 	extern int hackpid, locknum;
242 	int i = 0, fd;
243 
244 	(void) fflush(stdout);
245 
246 	/* we ignore QUIT and INT at this point */
247 	if (link(HLOCK, LLOCK) == -1) {
248 		int errnosv = errno;
249 
250 		perror(HLOCK);
251 		printf("Cannot link %s to %s\n", LLOCK, HLOCK);
252 		switch(errnosv) {
253 		case ENOENT:
254 		    printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
255 		    break;
256 		case EACCES:
257 		    printf("It seems you don't have write permission here.\n");
258 		    break;
259 		case EEXIST:
260 		    printf("(Try again or rm %s.)\n", LLOCK);
261 		    break;
262 		default:
263 		    printf("I don't know what is wrong.");
264 		}
265 		getret();
266 		error("");
267 		/*NOTREACHED*/
268 	}
269 
270 	regularize(lock);
271 	glo(0);
272 	if(locknum > 25) locknum = 25;
273 
274 	do {
275 		if(locknum) lock[0] = 'a' + i++;
276 
277 		if((fd = open(lock, O_RDONLY)) == -1) {
278 			if(errno == ENOENT) goto gotlock;    /* no such file */
279 			perror(lock);
280 			(void) unlink(LLOCK);
281 			error("Cannot open %s", lock);
282 		}
283 
284 		if(veryold(fd))	/* if true, this closes fd and unlinks lock */
285 			goto gotlock;
286 		(void) close(fd);
287 	} while(i < locknum);
288 
289 	(void) unlink(LLOCK);
290 	error(locknum ? "Too many hacks running now."
291 		      : "There is a game in progress under your name.");
292 gotlock:
293 	fd = creat(lock, FMASK);
294 	if(unlink(LLOCK) == -1)
295 		error("Cannot unlink %s.", LLOCK);
296 	if(fd == -1) {
297 		error("cannot creat lock file.");
298 	} else {
299 		if(write(fd, (char *) &hackpid, sizeof(hackpid))
300 		    != sizeof(hackpid)){
301 			error("cannot write lock");
302 		}
303 		if(close(fd) == -1) {
304 			error("cannot close lock");
305 		}
306 	}
307 }
308 
309 #ifdef MAIL
310 
311 /*
312  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
313  * I don't know the details of his implementation.]
314  * { Later note: he disliked my calling a general mailreader and felt that
315  *   hack should do the paging itself. But when I get mail, I want to put it
316  *   in some folder, reply, etc. - it would be unreasonable to put all these
317  *   functions in hack. }
318  * The mail daemon '2' is at present not a real monster, but only a visual
319  * effect. Thus, makemon() is superfluous. This might become otherwise,
320  * however. The motion of '2' is less restrained than usual: diagonal moves
321  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
322  * in a ROOM, even when you are Blind.
323  * Its path should be longer when you are Telepat-hic and Blind.
324  *
325  * Interesting side effects:
326  *	- You can get rich by sending yourself a lot of mail and selling
327  *	  it to the shopkeeper. Unfortunately mail isn't very valuable.
328  *	- You might die in case '2' comes along at a critical moment during
329  *	  a fight and delivers a scroll the weight of which causes you to
330  *	  collapse.
331  *
332  * Possible extensions:
333  *	- Open the file MAIL and do fstat instead of stat for efficiency.
334  *	  (But sh uses stat, so this cannot be too bad.)
335  *	- Examine the mail and produce a scroll of mail called "From somebody".
336  *	- Invoke MAILREADER in such a way that only this single letter is read.
337  *
338  *	- Make him lose his mail when a Nymph steals the letter.
339  *	- Do something to the text when the scroll is enchanted or cancelled.
340  */
341 static struct stat omstat,nmstat;
342 static char *mailbox;
343 static long laststattime;
344 
345 void
346 getmailstatus()
347 {
348 	if(!(mailbox = getenv("MAIL")))
349 		return;
350 	if(stat(mailbox, &omstat)){
351 #ifdef PERMANENT_MAILBOX
352 		pline("Cannot get status of MAIL=%s .", mailbox);
353 		mailbox = 0;
354 #else
355 		omstat.st_mtime = 0;
356 #endif /* PERMANENT_MAILBOX */
357 	}
358 }
359 
360 void
361 ckmailstatus()
362 {
363 	if(!mailbox
364 #ifdef MAILCKFREQ
365 		    || moves < laststattime + MAILCKFREQ
366 #endif /* MAILCKFREQ */
367 							)
368 		return;
369 	laststattime = moves;
370 	if(stat(mailbox, &nmstat)){
371 #ifdef PERMANENT_MAILBOX
372 		pline("Cannot get status of MAIL=%s anymore.", mailbox);
373 		mailbox = 0;
374 #else
375 		nmstat.st_mtime = 0;
376 #endif /* PERMANENT_MAILBOX */
377 	} else if(nmstat.st_mtime > omstat.st_mtime) {
378 		if(nmstat.st_size)
379 			newmail();
380 		getmailstatus();	/* might be too late ... */
381 	}
382 }
383 
384 static void
385 newmail()
386 {
387 	/* produce a scroll of mail */
388 	struct obj *obj;
389 	struct monst *md;
390 	extern char plname[];
391 	extern struct obj *mksobj();
392 	extern struct monst *makemon();
393 	extern struct permonst pm_mail_daemon;
394 
395 	obj = mksobj(SCR_MAIL);
396 	if(md = makemon(&pm_mail_daemon, u.ux, u.uy)) /* always succeeds */
397 		mdrush(md,0);
398 
399 	pline("\"Hello, %s! I have some mail for you.\"", plname);
400 	if(md) {
401 		if(dist(md->mx,md->my) > 2)
402 			pline("\"Catch!\"");
403 		more();
404 
405 		/* let him disappear again */
406 		mdrush(md,1);
407 		mondead(md);
408 	}
409 
410 	obj = addinv(obj);
411 	(void) identify(obj);		/* set known and do prinv() */
412 }
413 
414 /* make md run through the cave */
415 static void
416 mdrush(struct monst *md, boolean away)
417 {
418 	int uroom = inroom(u.ux, u.uy);
419 	if(uroom >= 0) {
420 		int tmp = rooms[uroom].fdoor;
421 		int cnt = rooms[uroom].doorct;
422 		int fx = u.ux, fy = u.uy;
423 		while(cnt--) {
424 			if(dist(fx,fy) < dist(doors[tmp].x, doors[tmp].y)){
425 				fx = doors[tmp].x;
426 				fy = doors[tmp].y;
427 			}
428 			tmp++;
429 		}
430 		tmp_at(-1, md->data->mlet);	/* open call */
431 		if(away) {	/* interchange origin and destination */
432 			unpmon(md);
433 			tmp = fx; fx = md->mx; md->mx = tmp;
434 			tmp = fy; fy = md->my; md->my = tmp;
435 		}
436 		while(fx != md->mx || fy != md->my) {
437 			int dx,dy,nfx = fx,nfy = fy,d1,d2;
438 
439 			tmp_at(fx,fy);
440 			d1 = DIST(fx,fy,md->mx,md->my);
441 			for(dx = -1; dx <= 1; dx++) for(dy = -1; dy <= 1; dy++)
442 			    if(dx || dy) {
443 				d2 = DIST(fx+dx,fy+dy,md->mx,md->my);
444 				if(d2 < d1) {
445 				    d1 = d2;
446 				    nfx = fx+dx;
447 				    nfy = fy+dy;
448 				}
449 			    }
450 			if(nfx != fx || nfy != fy) {
451 			    fx = nfx;
452 			    fy = nfy;
453 			} else {
454 			    if(!away) {
455 				md->mx = fx;
456 				md->my = fy;
457 			    }
458 			    break;
459 			}
460 		}
461 		tmp_at(-1,-1);			/* close call */
462 	}
463 	if(!away)
464 		pmon(md);
465 }
466 
467 void
468 readmail()
469 {
470 #ifdef DEF_MAILREADER			/* This implies that UNIX is defined */
471 	char *mr = 0;
472 	more();
473 	if(!(mr = getenv("MAILREADER")))
474 		mr = DEF_MAILREADER;
475 	if(child(1)){
476 		execl(mr, mr, (char *) 0);
477 		exit(1);
478 	}
479 #else /* DEF_MAILREADER */
480 	(void) page_file(mailbox, FALSE);
481 #endif /* DEF_MAILREADER */
482 	/* get new stat; not entirely correct: there is a small time
483 	   window where we do not see new mail */
484 	getmailstatus();
485 }
486 #endif /* MAIL */
487 
488 /* normalize file name - we don't like ..'s or /'s */
489 void
490 regularize(char *s)
491 {
492 	char *lp;
493 
494 	while((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
495 		*lp = '_';
496 }
497