xref: /dragonfly/games/hack/hack.unix.c (revision 2038fb68) 
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"	/* mainly for index() which depends on BSD */
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 = rindex(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)) return(0);			/* cannot get status */
129 	if(buf.st_size != sizeof(int)) return(0);	/* not an xlock file */
130 	time(&date);
131 	if(date - buf.st_mtime < 3L*24L*60L*60L) {	/* recent */
132 		int lockedpid;	/* should be the same size as hackpid */
133 
134 		if(read(fd, (char *)&lockedpid, sizeof(lockedpid)) !=
135 			sizeof(lockedpid))
136 			/* strange ... */
137 			return(0);
138 
139 		/* From: Rick Adams <seismo!rick> */
140 		/* This will work on 4.1cbsd, 4.2bsd and system 3? & 5. */
141 		/* It will do nothing on V7 or 4.1bsd. */
142 		if(!(kill(lockedpid, 0) == -1 && errno == ESRCH))
143 			return(0);
144 	}
145 	close(fd);
146 	for(i = 1; i <= MAXLEVEL; i++) {		/* try to remove all */
147 		glo(i);
148 		unlink(lock);
149 	}
150 	glo(0);
151 	if(unlink(lock)) return(0);			/* cannot remove it */
152 	return(1);					/* success! */
153 }
154 
155 void
156 getlock(void)
157 {
158 	int i = 0, fd;
159 
160 	fflush(stdout);
161 
162 	/* we ignore QUIT and INT at this point */
163 	if (link(HLOCK, LLOCK) == -1) {
164 		int errnosv = errno;
165 
166 		perror(HLOCK);
167 		printf("Cannot link %s to %s\n", LLOCK, HLOCK);
168 		switch(errnosv) {
169 		case ENOENT:
170 		    printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
171 		    break;
172 		case EACCES:
173 		    printf("It seems you don't have write permission here.\n");
174 		    break;
175 		case EEXIST:
176 		    printf("(Try again or rm %s.)\n", LLOCK);
177 		    break;
178 		default:
179 		    printf("I don't know what is wrong.");
180 		}
181 		getret();
182 		error("");
183 		/*NOTREACHED*/
184 	}
185 
186 	regularize(lock);
187 	glo(0);
188 	if(locknum > 25) locknum = 25;
189 
190 	do {
191 		if(locknum) lock[0] = 'a' + i++;
192 
193 		if((fd = open(lock, 0)) == -1) {
194 			if(errno == ENOENT) goto gotlock;    /* no such file */
195 			perror(lock);
196 			unlink(LLOCK);
197 			error("Cannot open %s", lock);
198 		}
199 
200 		if(veryold(fd))	/* if true, this closes fd and unlinks lock */
201 			goto gotlock;
202 		close(fd);
203 	} while(i < locknum);
204 
205 	unlink(LLOCK);
206 	error(locknum ? "Too many hacks running now."
207 		      : "There is a game in progress under your name.");
208 gotlock:
209 	fd = creat(lock, FMASK);
210 	if(unlink(LLOCK) == -1)
211 		error("Cannot unlink %s.", LLOCK);
212 	if(fd == -1) {
213 		error("cannot creat lock file.");
214 	} else {
215 		if(write(fd, (char *) &hackpid, sizeof(hackpid))
216 		    != sizeof(hackpid)){
217 			error("cannot write lock");
218 		}
219 		if(close(fd) == -1) {
220 			error("cannot close lock");
221 		}
222 	}
223 }
224 
225 #ifdef MAIL
226 
227 /*
228  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
229  * I don't know the details of his implementation.]
230  * { Later note: he disliked my calling a general mailreader and felt that
231  *   hack should do the paging itself. But when I get mail, I want to put it
232  *   in some folder, reply, etc. - it would be unreasonable to put all these
233  *   functions in hack. }
234  * The mail daemon '2' is at present not a real monster, but only a visual
235  * effect. Thus, makemon() is superfluous. This might become otherwise,
236  * however. The motion of '2' is less restrained than usual: diagonal moves
237  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
238  * in a ROOM, even when you are Blind.
239  * Its path should be longer when you are Telepat-hic and Blind.
240  *
241  * Interesting side effects:
242  *	- You can get rich by sending yourself a lot of mail and selling
243  *	  it to the shopkeeper. Unfortunately mail isn't very valuable.
244  *	- You might die in case '2' comes along at a critical moment during
245  *	  a fight and delivers a scroll the weight of which causes you to
246  *	  collapse.
247  *
248  * Possible extensions:
249  *	- Open the file MAIL and do fstat instead of stat for efficiency.
250  *	  (But sh uses stat, so this cannot be too bad.)
251  *	- Examine the mail and produce a scroll of mail called "From somebody".
252  *	- Invoke MAILREADER in such a way that only this single letter is read.
253  *
254  *	- Make him lose his mail when a Nymph steals the letter.
255  *	- Do something to the text when the scroll is enchanted or cancelled.
256  */
257 #include	"def.mkroom.h"
258 static struct stat omstat,nmstat;
259 static char *mailbox;
260 static long laststattime;
261 
262 void
263 getmailstatus(void)
264 {
265 	if(!(mailbox = getenv("MAIL")))
266 		return;
267 	if(stat(mailbox, &omstat)){
268 #ifdef PERMANENT_MAILBOX
269 		pline("Cannot get status of MAIL=%s .", mailbox);
270 		mailbox = 0;
271 #else
272 		omstat.st_mtime = 0;
273 #endif /* PERMANENT_MAILBOX */
274 	}
275 }
276 
277 void
278 ckmailstatus(void)
279 {
280 	if(!mailbox
281 #ifdef MAILCKFREQ
282 		    || moves < laststattime + MAILCKFREQ
283 #endif /* MAILCKFREQ */
284 							)
285 		return;
286 	laststattime = moves;
287 	if(stat(mailbox, &nmstat)){
288 #ifdef PERMANENT_MAILBOX
289 		pline("Cannot get status of MAIL=%s anymore.", mailbox);
290 		mailbox = 0;
291 #else
292 		nmstat.st_mtime = 0;
293 #endif /* PERMANENT_MAILBOX */
294 	} else if(nmstat.st_mtime > omstat.st_mtime) {
295 		if(nmstat.st_size)
296 			newmail();
297 		getmailstatus();	/* might be too late ... */
298 	}
299 }
300 
301 static void
302 newmail(void)
303 {
304 	/* produce a scroll of mail */
305 	struct obj *obj;
306 	struct monst *md;
307 	extern struct permonst pm_mail_daemon;
308 
309 	obj = mksobj(SCR_MAIL);
310 	if(md = makemon(&pm_mail_daemon, u.ux, u.uy)) /* always succeeds */
311 		mdrush(md,0);
312 
313 	pline("\"Hello, %s! I have some mail for you.\"", plname);
314 	if(md) {
315 		if(dist(md->mx,md->my) > 2)
316 			pline("\"Catch!\"");
317 		more();
318 
319 		/* let him disappear again */
320 		mdrush(md,1);
321 		mondead(md);
322 	}
323 
324 	obj = addinv(obj);
325 	identify(obj);		/* set known and do prinv() */
326 }
327 
328 /* make md run through the cave */
329 static void
330 mdrush(struct monst *md, bool away)
331 {
332 	int uroom = inroom(u.ux, u.uy);
333 	if(uroom >= 0) {
334 		int tmp = rooms[uroom].fdoor;
335 		int cnt = rooms[uroom].doorct;
336 		int fx = u.ux, fy = u.uy;
337 		while(cnt--) {
338 			if(dist(fx,fy) < dist(doors[tmp].x, doors[tmp].y)){
339 				fx = doors[tmp].x;
340 				fy = doors[tmp].y;
341 			}
342 			tmp++;
343 		}
344 		tmp_at(-1, md->data->mlet);	/* open call */
345 		if(away) {	/* interchange origin and destination */
346 			unpmon(md);
347 			tmp = fx; fx = md->mx; md->mx = tmp;
348 			tmp = fy; fy = md->my; md->my = tmp;
349 		}
350 		while(fx != md->mx || fy != md->my) {
351 			int dx,dy,nfx = fx,nfy = fy,d1,d2;
352 
353 			tmp_at(fx,fy);
354 			d1 = DIST(fx,fy,md->mx,md->my);
355 			for(dx = -1; dx <= 1; dx++) for(dy = -1; dy <= 1; dy++)
356 			    if(dx || dy) {
357 				d2 = DIST(fx+dx,fy+dy,md->mx,md->my);
358 				if(d2 < d1) {
359 				    d1 = d2;
360 				    nfx = fx+dx;
361 				    nfy = fy+dy;
362 				}
363 			    }
364 			if(nfx != fx || nfy != fy) {
365 			    fx = nfx;
366 			    fy = nfy;
367 			} else {
368 			    if(!away) {
369 				md->mx = fx;
370 				md->my = fy;
371 			    }
372 			    break;
373 			}
374 		}
375 		tmp_at(-1,-1);			/* close call */
376 	}
377 	if(!away)
378 		pmon(md);
379 }
380 
381 void
382 readmail(void)
383 {
384 #ifdef DEF_MAILREADER			/* This implies that UNIX is defined */
385 	char *mr = 0;
386 	more();
387 	if(!(mr = getenv("MAILREADER")))
388 		mr = DEF_MAILREADER;
389 	if(child(1)){
390 		execl(mr, mr, NULL);
391 		exit(1);
392 	}
393 #else /* DEF_MAILREADER */
394 	page_file(mailbox, FALSE);
395 #endif /* DEF_MAILREADER */
396 	/* get new stat; not entirely correct: there is a small time
397 	   window where we do not see new mail */
398 	getmailstatus();
399 }
400 #endif /* MAIL */
401 
402 void
403 regularize(char *s)	/* normalize file name - we don't like ..'s or /'s */
404 {
405 	char *lp;
406 
407 	while((lp = index(s, '.')) || (lp = index(s, '/')))
408 		*lp = '_';
409 }
410