hack.unix.c revision 1.11 
1/*	$NetBSD: hack.unix.c,v 1.11 2009/06/07 18:30:39 dholland 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#include <sys/cdefs.h>
65#ifndef lint
66__RCSID("$NetBSD: hack.unix.c,v 1.11 2009/06/07 18:30:39 dholland Exp $");
67#endif				/* not lint */
68
69/* This file collects some Unix dependencies; hack.pager.c contains some more */
70
71/*
72 * The time is used for:
73 *	- seed for random()
74 *	- year on tombstone and yymmdd in record file
75 *	- phase of the moon (various monsters react to NEW_MOON or FULL_MOON)
76 *	- night and midnight (the undead are dangerous at midnight)
77 *	- determination of what files are "very old"
78 */
79
80#include <errno.h>
81#include <sys/types.h>	/* for time_t and stat */
82#include <sys/stat.h>
83#ifdef BSD
84#include <sys/time.h>
85#else
86#include <time.h>
87#endif	/* BSD */
88#include <stdlib.h>
89#include <unistd.h>
90#include <signal.h>
91#include <fcntl.h>
92
93#include "hack.h"		/* mainly for strchr() which depends on BSD */
94#include "extern.h"
95
96extern int locknum;
97
98
99void
100setrandom(void)
101{
102	(void) srandom((int) time((time_t *) 0));
103}
104
105struct tm      *
106getlt(void)
107{
108	time_t          date;
109
110	(void) time(&date);
111	return (localtime(&date));
112}
113
114int
115getyear(void)
116{
117	return (1900 + getlt()->tm_year);
118}
119
120char           *
121getdatestr(void)
122{
123	static char     datestr[7];
124	struct tm      *lt = getlt();
125
126	(void) sprintf(datestr, "%02d%02d%02d",
127		       lt->tm_year % 100, lt->tm_mon + 1, lt->tm_mday);
128	return (datestr);
129}
130
131int
132phase_of_the_moon(void)
133{				/* 0-7, with 0: new, 4: full *//* moon
134				 * period: 29.5306 days */
135	/* year: 365.2422 days */
136	struct tm      *lt = getlt();
137	int             epact, diy, golden;
138
139	diy = lt->tm_yday;
140	golden = (lt->tm_year % 19) + 1;
141	epact = (11 * golden + 18) % 30;
142	if ((epact == 25 && golden > 11) || epact == 24)
143		epact++;
144
145	return ((((((diy + epact) * 6) + 11) % 177) / 22) & 7);
146}
147
148int
149night(void)
150{
151	int             hour = getlt()->tm_hour;
152
153	return (hour < 6 || hour > 21);
154}
155
156int
157midnight(void)
158{
159	return (getlt()->tm_hour == 0);
160}
161
162struct stat     buf, hbuf;
163
164void
165gethdate(char *name)
166{
167#if 0
168	/* old version - for people short of space */
169
170	char *np;
171
172	if(stat(name, &hbuf))
173	    error("Cannot get status of %s.",
174		(np = strrchr(name, '/')) ? np+1 : name);
175#else
176	/* version using PATH from: seismo!gregc@ucsf-cgl.ARPA (Greg Couch) */
177
178
179	/*
180	 * The problem with   #include	<sys/param.h>   is that this include file
181	 * does not exist on all systems, and moreover, that it sometimes includes
182	 * <sys/types.h> again, so that the compiler sees these typedefs twice.
183	 */
184#define		MAXPATHLEN	1024
185
186	const char           *np, *path;
187	char            filename[MAXPATHLEN + 1];
188	if (strchr(name, '/') != NULL || (path = getenv("PATH")) == NULL)
189		path = "";
190
191	for (;;) {
192		if ((np = strchr(path, ':')) == NULL)
193			np = path + strlen(path);	/* point to end str */
194		if (np - path <= 1)	/* %% */
195			(void) strcpy(filename, name);
196		else {
197			(void) strncpy(filename, path, np - path);
198			filename[np - path] = '/';
199			(void) strcpy(filename + (np - path) + 1, name);
200		}
201		if (stat(filename, &hbuf) == 0)
202			return;
203		if (*np == '\0')
204			break;
205		path = np + 1;
206	}
207	error("Cannot get status of %s.",
208	      (np = strrchr(name, '/')) ? np + 1 : name);
209#endif
210}
211
212int
213uptodate(int fd)
214{
215	if (fstat(fd, &buf)) {
216		pline("Cannot get status of saved level? ");
217		return (0);
218	}
219	if (buf.st_mtime < hbuf.st_mtime) {
220		pline("Saved level is out of date. ");
221		return (0);
222	}
223	return (1);
224}
225
226/* see whether we should throw away this xlock file */
227int
228veryold(int fd)
229{
230	int             i;
231	time_t          date;
232
233	if (fstat(fd, &buf))
234		return (0);	/* cannot get status */
235	if (buf.st_size != sizeof(int))
236		return (0);	/* not an xlock file */
237	(void) time(&date);
238	if (date - buf.st_mtime < 3L * 24L * 60L * 60L) {	/* recent */
239		int             lockedpid;	/* should be the same size as
240						 * hackpid */
241
242		if (read(fd, (char *) &lockedpid, sizeof(lockedpid)) !=
243		    sizeof(lockedpid))
244			/* strange ... */
245			return (0);
246
247		/*
248		 * From: Rick Adams <seismo!rick> This will work on
249		 * 4.1cbsd, 4.2bsd and system 3? & 5. It will do nothing
250		 * on V7 or 4.1bsd.
251		 */
252		if (!(kill(lockedpid, 0) == -1 && errno == ESRCH))
253			return (0);
254	}
255	(void) close(fd);
256	for (i = 1; i <= MAXLEVEL; i++) {	/* try to remove all */
257		glo(i);
258		(void) unlink(lock);
259	}
260	glo(0);
261	if (unlink(lock))
262		return (0);	/* cannot remove it */
263	return (1);		/* success! */
264}
265
266void
267getlock(void)
268{
269	int             i = 0, fd;
270
271	(void) fflush(stdout);
272
273	/* we ignore QUIT and INT at this point */
274	if (link(HLOCK, LLOCK) == -1) {
275		int             errnosv = errno;
276
277		perror(HLOCK);
278		printf("Cannot link %s to %s\n", LLOCK, HLOCK);
279		switch (errnosv) {
280		case ENOENT:
281			printf("Perhaps there is no (empty) file %s ?\n", HLOCK);
282			break;
283		case EACCES:
284			printf("It seems you don't have write permission here.\n");
285			break;
286		case EEXIST:
287			printf("(Try again or rm %s.)\n", LLOCK);
288			break;
289		default:
290			printf("I don't know what is wrong.");
291		}
292		getret();
293		error("%s", "");
294		/* NOTREACHED */
295	}
296	regularize(lock);
297	glo(0);
298	if (locknum > 25)
299		locknum = 25;
300
301	do {
302		if (locknum)
303			lock[0] = 'a' + i++;
304
305		if ((fd = open(lock, O_RDONLY)) == -1) {
306			if (errno == ENOENT)
307				goto gotlock;	/* no such file */
308			perror(lock);
309			(void) unlink(LLOCK);
310			error("Cannot open %s", lock);
311		}
312		if (veryold(fd))/* if true, this closes fd and unlinks lock */
313			goto gotlock;
314		(void) close(fd);
315	} while (i < locknum);
316
317	(void) unlink(LLOCK);
318	error(locknum ? "Too many hacks running now."
319	      : "There is a game in progress under your name.");
320gotlock:
321	fd = creat(lock, FMASK);
322	if (unlink(LLOCK) == -1)
323		error("Cannot unlink %s.", LLOCK);
324	if (fd == -1) {
325		error("cannot creat lock file.");
326	} else {
327		if (write(fd, (char *) &hackpid, sizeof(hackpid))
328		    != sizeof(hackpid)) {
329			error("cannot write lock");
330		}
331		if (close(fd) == -1) {
332			error("cannot close lock");
333		}
334	}
335}
336
337#ifdef MAIL
338
339/*
340 * Notify user when new mail has arrived. [Idea from Merlyn Leroy, but
341 * I don't know the details of his implementation.]
342 * { Later note: he disliked my calling a general mailreader and felt that
343 *   hack should do the paging itself. But when I get mail, I want to put it
344 *   in some folder, reply, etc. - it would be unreasonable to put all these
345 *   functions in hack. }
346 * The mail daemon '2' is at present not a real monster, but only a visual
347 * effect. Thus, makemon() is superfluous. This might become otherwise,
348 * however. The motion of '2' is less restrained than usual: diagonal moves
349 * from a DOOR are possible. He might also use SDOOR's. Also, '2' is visible
350 * in a ROOM, even when you are Blind.
351 * Its path should be longer when you are Telepat-hic and Blind.
352 *
353 * Interesting side effects:
354 *	- You can get rich by sending yourself a lot of mail and selling
355 *	  it to the shopkeeper. Unfortunately mail isn't very valuable.
356 *	- You might die in case '2' comes along at a critical moment during
357 *	  a fight and delivers a scroll the weight of which causes you to
358 *	  collapse.
359 *
360 * Possible extensions:
361 *	- Open the file MAIL and do fstat instead of stat for efficiency.
362 *	  (But sh uses stat, so this cannot be too bad.)
363 *	- Examine the mail and produce a scroll of mail called "From somebody".
364 *	- Invoke MAILREADER in such a way that only this single letter is read.
365 *
366 *	- Make him lose his mail when a Nymph steals the letter.
367 *	- Do something to the text when the scroll is enchanted or cancelled.
368 */
369#include	"def.mkroom.h"
370static struct stat omstat, nmstat;
371static char    *mailbox;
372static long     laststattime;
373
374void
375getmailstatus(void)
376{
377	if (!(mailbox = getenv("MAIL")))
378		return;
379	if (stat(mailbox, &omstat)) {
380#ifdef PERMANENT_MAILBOX
381		pline("Cannot get status of MAIL=%s .", mailbox);
382		mailbox = 0;
383#else
384		omstat.st_mtime = 0;
385#endif	/* PERMANENT_MAILBOX */
386	}
387}
388
389void
390ckmailstatus(void)
391{
392	if (!mailbox
393#ifdef MAILCKFREQ
394	    || moves < laststattime + MAILCKFREQ
395#endif	/* MAILCKFREQ */
396		)
397		return;
398	laststattime = moves;
399	if (stat(mailbox, &nmstat)) {
400#ifdef PERMANENT_MAILBOX
401		pline("Cannot get status of MAIL=%s anymore.", mailbox);
402		mailbox = 0;
403#else
404		nmstat.st_mtime = 0;
405#endif	/* PERMANENT_MAILBOX */
406	} else if (nmstat.st_mtime > omstat.st_mtime) {
407		if (nmstat.st_size)
408			newmail();
409		getmailstatus();/* might be too late ... */
410	}
411}
412
413void
414newmail(void)
415{
416	/* produce a scroll of mail */
417	struct obj     *obj;
418	struct monst   *md;
419
420	obj = mksobj(SCR_MAIL);
421	if (md = makemon(&pm_mail_daemon, u.ux, u.uy))	/* always succeeds */
422		mdrush(md, 0);
423
424	pline("\"Hello, %s! I have some mail for you.\"", plname);
425	if (md) {
426		if (dist(md->mx, md->my) > 2)
427			pline("\"Catch!\"");
428		more();
429
430		/* let him disappear again */
431		mdrush(md, 1);
432		mondead(md);
433	}
434	obj = addinv(obj);
435	(void) identify(obj);	/* set known and do prinv() */
436}
437
438/* make md run through the cave */
439void
440mdrush(struct monst *md, boolean away)
441{
442	int             uroom = inroom(u.ux, u.uy);
443	if (uroom >= 0) {
444		int             tmp = rooms[uroom].fdoor;
445		int             cnt = rooms[uroom].doorct;
446		int             fx = u.ux, fy = u.uy;
447		while (cnt--) {
448			if (dist(fx, fy) < dist(doors[tmp].x, doors[tmp].y)) {
449				fx = doors[tmp].x;
450				fy = doors[tmp].y;
451			}
452			tmp++;
453		}
454		tmp_at(-1, md->data->mlet);	/* open call */
455		if (away) {	/* interchange origin and destination */
456			unpmon(md);
457			tmp = fx;
458			fx = md->mx;
459			md->mx = tmp;
460			tmp = fy;
461			fy = md->my;
462			md->my = tmp;
463		}
464		while (fx != md->mx || fy != md->my) {
465			int             dx, dy, nfx = fx, nfy = fy, d1,
466			                d2;
467
468			tmp_at(fx, fy);
469			d1 = DIST(fx, fy, md->mx, md->my);
470			for (dx = -1; dx <= 1; dx++)
471				for (dy = -1; dy <= 1; dy++)
472					if (dx || dy) {
473						d2 = DIST(fx + dx, fy + dy, md->mx, md->my);
474						if (d2 < d1) {
475							d1 = d2;
476							nfx = fx + dx;
477							nfy = fy + dy;
478						}
479					}
480			if (nfx != fx || nfy != fy) {
481				fx = nfx;
482				fy = nfy;
483			} else {
484				if (!away) {
485					md->mx = fx;
486					md->my = fy;
487				}
488				break;
489			}
490		}
491		tmp_at(-1, -1);	/* close call */
492	}
493	if (!away)
494		pmon(md);
495}
496
497void
498readmail(void)
499{
500#ifdef DEF_MAILREADER		/* This implies that UNIX is defined */
501	char           *mr = 0;
502	more();
503	if (!(mr = getenv("MAILREADER")))
504		mr = DEF_MAILREADER;
505	if (child(1)) {
506		execl(mr, mr, (char *) 0);
507		exit(1);
508	}
509#else	/* DEF_MAILREADER */
510	(void) page_file(mailbox, FALSE);
511#endif	/* DEF_MAILREADER */
512	/*
513	 * get new stat; not entirely correct: there is a small time window
514	 * where we do not see new mail
515	 */
516	getmailstatus();
517}
518#endif	/* MAIL */
519
520/*
521 * normalize file name - we don't like ..'s or /'s
522 */
523void
524regularize(char *s)
525{
526	char           *lp;
527
528	while ((lp = strchr(s, '.')) || (lp = strchr(s, '/')))
529		*lp = '_';
530}
531