xref: /openbsd/games/hack/hack.unix.c (revision d25d28bf)
1 /*	$OpenBSD: hack.unix.c,v 1.20 2016/09/11 14:21:17 tb 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 <sys/stat.h>
76 
77 #include <err.h>
78 #include <errno.h>
79 #include <limits.h>
80 #include <signal.h>
81 #include <stdio.h>
82 #include <stdlib.h>
83 #include <time.h>
84 #include <unistd.h>
85 
86 #include "hack.h"
87 
88 
89 static struct tm *getlt(void);
90 static int veryold(int);
91 #ifdef MAIL
92 static void newmail(void);
93 static void mdrush(struct monst *, boolean);
94 #endif
95 
96 static struct tm *
97 getlt(void)
98 {
99 	time_t date;
100 	struct tm *localtime();
101 
102 	(void) time(&date);
103 	return(localtime(&date));
104 }
105 
106 int
107 getyear(void)
108 {
109 	return(1900 + getlt()->tm_year);
110 }
111 
112 char *
113 getdate(void)
114 {
115 	static char datestr[7];
116 	struct tm *lt = getlt();
117 
118 	(void) snprintf(datestr, sizeof(datestr), "%02d%02d%02d",
119 		lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
120 	return(datestr);
121 }
122 
123 /*
124  * 0-7, with 0: new, 4: full
125  * moon period: 29.5306 days
126  * year: 365.2422 days
127  */
128 int
129 phase_of_the_moon(void)
130 {
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(void)
145 {
146 	int hour = getlt()->tm_hour;
147 
148 	return(hour < 6 || hour > 21);
149 }
150 
151 int
152 midnight(void)
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[PATH_MAX+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(void)
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 	}
268 
269 	regularize(lock);
270 	glo(0);
271 	if(locknum > 25) locknum = 25;
272 
273 	do {
274 		if(locknum) lock[0] = 'a' + i++;
275 
276 		if((fd = open(lock, O_RDONLY)) == -1) {
277 			if(errno == ENOENT) goto gotlock;    /* no such file */
278 			perror(lock);
279 			(void) unlink(LLOCK);
280 			error("Cannot open %s", lock);
281 		}
282 
283 		if(veryold(fd))	/* if true, this closes fd and unlinks lock */
284 			goto gotlock;
285 		(void) close(fd);
286 	} while(i < locknum);
287 
288 	(void) unlink(LLOCK);
289 	error(locknum ? "Too many hacks running now."
290 		      : "There is a game in progress under your name.");
291 gotlock:
292 	fd = open(lock, O_CREAT | O_TRUNC | O_WRONLY, FMASK);
293 	if(unlink(LLOCK) == -1)
294 		error("Cannot unlink %s.", LLOCK);
295 	if(fd == -1) {
296 		error("cannot creat lock file.");
297 	} else {
298 		if(write(fd, (char *) &hackpid, sizeof(hackpid))
299 		    != sizeof(hackpid)){
300 			error("cannot write lock");
301 		}
302 		if(close(fd) == -1) {
303 			error("cannot close lock");
304 		}
305 	}
306 }
307 
308 #ifdef MAIL
309 
310 /*
311  * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
312  * I don't know the details of his implementation.]
313  * { Later note: he disliked my calling a general mailreader and felt that
314  *   hack should do the paging itself. But when I get mail, I want to put it
315  *   in some folder, reply, etc. - it would be unreasonable to put all these
316  *   functions in hack. }
317  * The mail daemon '2' is at present not a real monster, but only a visual
318  * effect. Thus, makemon() is superfluous. This might become otherwise,
319  * however. The motion of '2' is less restrained than usual: diagonal moves
320  * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
321  * in a ROOM, even when you are Blind.
322  * Its path should be longer when you are Telepat-hic and Blind.
323  *
324  * Interesting side effects:
325  *	- You can get rich by sending yourself a lot of mail and selling
326  *	  it to the shopkeeper. Unfortunately mail isn't very valuable.
327  *	- You might die in case '2' comes along at a critical moment during
328  *	  a fight and delivers a scroll the weight of which causes you to
329  *	  collapse.
330  *
331  * Possible extensions:
332  *	- Open the file MAIL and do fstat instead of stat for efficiency.
333  *	  (But sh uses stat, so this cannot be too bad.)
334  *	- Examine the mail and produce a scroll of mail called "From somebody".
335  *	- Invoke MAILREADER in such a way that only this single letter is read.
336  *
337  *	- Make him lose his mail when a Nymph steals the letter.
338  *	- Do something to the text when the scroll is enchanted or cancelled.
339  */
340 static struct stat omstat,nmstat;
341 static char *mailbox;
342 static long laststattime;
343 
344 void
345 getmailstatus(void)
346 {
347 	if(!(mailbox = getenv("MAIL")))
348 		return;
349 	if(stat(mailbox, &omstat)){
350 #ifdef PERMANENT_MAILBOX
351 		pline("Cannot get status of MAIL=%s .", mailbox);
352 		mailbox = 0;
353 #else
354 		omstat.st_mtime = 0;
355 #endif /* PERMANENT_MAILBOX */
356 	}
357 }
358 
359 void
360 ckmailstatus(void)
361 {
362 	if(!mailbox
363 #ifdef MAILCKFREQ
364 		    || moves < laststattime + MAILCKFREQ
365 #endif /* MAILCKFREQ */
366 							)
367 		return;
368 	laststattime = moves;
369 	if(stat(mailbox, &nmstat)){
370 #ifdef PERMANENT_MAILBOX
371 		pline("Cannot get status of MAIL=%s anymore.", mailbox);
372 		mailbox = 0;
373 #else
374 		nmstat.st_mtime = 0;
375 #endif /* PERMANENT_MAILBOX */
376 	} else if(nmstat.st_mtime > omstat.st_mtime) {
377 		if(nmstat.st_size)
378 			newmail();
379 		getmailstatus();	/* might be too late ... */
380 	}
381 }
382 
383 static void
384 newmail(void)
385 {
386 	/* produce a scroll of mail */
387 	struct obj *obj;
388 	struct monst *md;
389 	extern char plname[];
390 	extern struct obj *mksobj();
391 	extern struct monst *makemon();
392 	extern struct permonst pm_mail_daemon;
393 
394 	obj = mksobj(SCR_MAIL);
395 	if(md = makemon(&pm_mail_daemon, u.ux, u.uy)) /* always succeeds */
396 		mdrush(md,0);
397 
398 	pline("\"Hello, %s! I have some mail for you.\"", plname);
399 	if(md) {
400 		if(dist(md->mx,md->my) > 2)
401 			pline("\"Catch!\"");
402 		more();
403 
404 		/* let him disappear again */
405 		mdrush(md,1);
406 		mondead(md);
407 	}
408 
409 	obj = addinv(obj);
410 	(void) identify(obj);		/* set known and do prinv() */
411 }
412 
413 /* make md run through the cave */
414 static void
415 mdrush(struct monst *md, boolean away)
416 {
417 	int uroom = inroom(u.ux, u.uy);
418 	if(uroom >= 0) {
419 		int tmp = rooms[uroom].fdoor;
420 		int cnt = rooms[uroom].doorct;
421 		int fx = u.ux, fy = u.uy;
422 		while(cnt--) {
423 			if(dist(fx,fy) < dist(doors[tmp].x, doors[tmp].y)){
424 				fx = doors[tmp].x;
425 				fy = doors[tmp].y;
426 			}
427 			tmp++;
428 		}
429 		tmp_at(-1, md->data->mlet);	/* open call */
430 		if(away) {	/* interchange origin and destination */
431 			unpmon(md);
432 			tmp = fx; fx = md->mx; md->mx = tmp;
433 			tmp = fy; fy = md->my; md->my = tmp;
434 		}
435 		while(fx != md->mx || fy != md->my) {
436 			int dx,dy,nfx = fx,nfy = fy,d1,d2;
437 
438 			tmp_at(fx,fy);
439 			d1 = DIST(fx,fy,md->mx,md->my);
440 			for(dx = -1; dx <= 1; dx++) for(dy = -1; dy <= 1; dy++)
441 			    if(dx || dy) {
442 				d2 = DIST(fx+dx,fy+dy,md->mx,md->my);
443 				if(d2 < d1) {
444 				    d1 = d2;
445 				    nfx = fx+dx;
446 				    nfy = fy+dy;
447 				}
448 			    }
449 			if(nfx != fx || nfy != fy) {
450 			    fx = nfx;
451 			    fy = nfy;
452 			} else {
453 			    if(!away) {
454 				md->mx = fx;
455 				md->my = fy;
456 			    }
457 			    break;
458 			}
459 		}
460 		tmp_at(-1,-1);			/* close call */
461 	}
462 	if(!away)
463 		pmon(md);
464 }
465 
466 void
467 readmail(void)
468 {
469 #ifdef DEF_MAILREADER			/* This implies that UNIX is defined */
470 	char *mr = 0;
471 	more();
472 	if(!(mr = getenv("MAILREADER")))
473 		mr = DEF_MAILREADER;
474 	if(child(1)){
475 		execl(mr, mr, (char *)NULL);
476 		exit(1);
477 	}
478 #else /* DEF_MAILREADER */
479 	(void) page_file(mailbox, FALSE);
480 #endif /* DEF_MAILREADER */
481 	/* get new stat; not entirely correct: there is a small time
482 	   window where we do not see new mail */
483 	getmailstatus();
484 }
485 #endif /* MAIL */
486 
487 /* normalize file name - we don't like ..'s or /'s */
488 void
489 regularize(char *s)
490 {
491 	char *lp;
492 
493 	while((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
494 		*lp = '_';
495 }
496