calendar.c revision 5311 
1/*
2 * Copyright (c) 1989, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char copyright[] =
36"@(#) Copyright (c) 1989, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)calendar.c	8.3 (Berkeley) 3/25/94";
42#endif /* not lint */
43
44#include <sys/param.h>
45#include <sys/time.h>
46#include <sys/stat.h>
47#include <sys/uio.h>
48#include <sys/wait.h>
49
50#include <ctype.h>
51#include <err.h>
52#include <errno.h>
53#include <fcntl.h>
54#include <pwd.h>
55#include <stdio.h>
56#include <stdlib.h>
57#include <string.h>
58#include <tzfile.h>
59#include <unistd.h>
60
61#include "pathnames.h"
62
63struct passwd *pw;
64int doall;
65
66void	 cal __P((void));
67void	 closecal __P((FILE *));
68int	 getday __P((char *));
69int	 getfield __P((char *, char **, int *));
70int	 getmonth __P((char *));
71int	 isnow __P((char *));
72FILE	*opencal __P((void));
73void	 settime __P((void));
74void	 usage __P((void));
75
76int
77main(argc, argv)
78	int argc;
79	char *argv[];
80{
81	extern int optind;
82	int ch;
83	char *s;
84
85	while ((ch = getopt(argc, argv, "-a")) != EOF)
86		switch (ch) {
87		case '-':		/* backward contemptible */
88		case 'a':
89			if (getuid()) {
90				errno = EPERM;
91				err(1, NULL);
92			}
93			doall = 1;
94			break;
95		case '?':
96		default:
97			usage();
98		}
99	argc -= optind;
100	argv += optind;
101
102	if (argc)
103		usage();
104
105	settime();
106	if (doall)
107		while ((pw = getpwent()) != NULL) {
108			(void)setegid(pw->pw_gid);
109			(void)seteuid(pw->pw_uid);
110			if (!chdir(pw->pw_dir))
111				cal();
112			(void)seteuid(0);
113		}
114	else {
115		if ((s = getenv("HOME")) != NULL)
116			chdir(s);
117		cal();
118	}
119	exit(0);
120}
121
122void
123cal()
124{
125	register int printing;
126	register char *p;
127	FILE *fp;
128	int ch;
129	char buf[2048 + 1];
130
131	if ((fp = opencal()) == NULL)
132		return;
133	for (printing = 0; fgets(buf, sizeof(buf), stdin) != NULL;) {
134		if ((p = strchr(buf, '\n')) != NULL)
135			*p = '\0';
136		else
137			while ((ch = getchar()) != '\n' && ch != EOF);
138		if (buf[0] == '\0')
139			continue;
140		if (buf[0] != '\t')
141			printing = isnow(buf) ? 1 : 0;
142		if (printing)
143			(void)fprintf(fp, "%s\n", buf);
144	}
145	closecal(fp);
146}
147
148struct iovec header[] = {
149	"From: ", 6,
150	NULL, 0,
151	" (Reminder Service)\nTo: ", 24,
152	NULL, 0,
153	"\nSubject: ", 10,
154	NULL, 0,
155	"'s Calendar\nPrecedence: bulk\n\n",  30,
156};
157
158/* 1-based month, 0-based days, cumulative */
159int daytab[][14] = {
160	0, -1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364,
161	0, -1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365,
162};
163struct tm *tp;
164int *cumdays, offset, yrdays;
165char dayname[10];
166
167void
168settime()
169{
170	time_t now;
171
172	(void)time(&now);
173	tp = localtime(&now);
174	if (isleap(tp->tm_year + 1900)) {
175		yrdays = DAYSPERLYEAR;
176		cumdays = daytab[1];
177	} else {
178		yrdays = DAYSPERNYEAR;
179		cumdays = daytab[0];
180	}
181	/* Friday displays Monday's events */
182	offset = tp->tm_wday == 5 ? 3 : 1;
183	header[5].iov_base = dayname;
184	header[5].iov_len = strftime(dayname, sizeof(dayname), "%A", tp);
185}
186
187/*
188 * Possible date formats include any combination of:
189 *	3-charmonth			(January, Jan, Jan)
190 *	3-charweekday			(Friday, Monday, mon.)
191 *	numeric month or day		(1, 2, 04)
192 *
193 * Any character may separate them, or they may not be separated.  Any line,
194 * following a line that is matched, that starts with "whitespace", is shown
195 * along with the matched line.
196 */
197int
198isnow(endp)
199	char *endp;
200{
201	int day, flags, month, v1, v2;
202
203#define	F_ISMONTH	0x01
204#define	F_ISDAY		0x02
205	flags = 0;
206	/* didn't recognize anything, skip it */
207	if (!(v1 = getfield(endp, &endp, &flags)))
208		return (0);
209	if (flags & F_ISDAY || v1 > 12) {
210		/* found a day */
211		day = v1;
212		/* if no recognizable month, assume just a day alone */
213		if (!(month = getfield(endp, &endp, &flags)))
214			month = tp->tm_mon + 1;
215	} else if (flags & F_ISMONTH) {
216		month = v1;
217		/* if no recognizable day, assume the first */
218		if (!(day = getfield(endp, &endp, &flags)))
219			day = 1;
220	} else {
221		v2 = getfield(endp, &endp, &flags);
222		if (flags & F_ISMONTH) {
223			day = v1;
224			month = v2;
225		} else {
226			/* F_ISDAY set, v2 > 12, or no way to tell */
227			month = v1;
228			/* if no recognizable day, assume the first */
229			day = v2 ? v2 : 1;
230		}
231	}
232	if (flags & F_ISDAY)
233		day = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
234	day = cumdays[month] + day;
235
236	/* if today or today + offset days */
237	if (day >= tp->tm_yday && day <= tp->tm_yday + offset)
238		return (1);
239	/* if number of days left in this year + days to event in next year */
240	if (yrdays - tp->tm_yday + day <= offset)
241		return (1);
242	return (0);
243}
244
245int
246getfield(p, endp, flags)
247	char *p, **endp;
248	int *flags;
249{
250	int val;
251	char *start, savech;
252
253	for (; !isdigit(*p) && !isalpha(*p) && *p != '*'; ++p);
254	if (*p == '*') {			/* `*' is current month */
255		*flags |= F_ISMONTH;
256		*endp = p+1;
257		return (tp->tm_mon + 1);
258	}
259	if (isdigit(*p)) {
260		val = strtol(p, &p, 10);	/* if 0, it's failure */
261		for (; !isdigit(*p) && !isalpha(*p) && *p != '*'; ++p);
262		*endp = p;
263		return (val);
264	}
265	for (start = p; isalpha(*++p););
266	savech = *p;
267	*p = '\0';
268	if ((val = getmonth(start)) != 0)
269		*flags |= F_ISMONTH;
270	else if ((val = getday(start)) != 0)
271		*flags |= F_ISDAY;
272	else {
273		*p = savech;
274		return (0);
275	}
276	for (*p = savech; !isdigit(*p) && !isalpha(*p) && *p != '*'; ++p);
277	*endp = p;
278	return (val);
279}
280
281char path[MAXPATHLEN + 1];
282
283FILE *
284opencal()
285{
286	int fd, pdes[2];
287
288	/* open up calendar file as stdin */
289	if (!freopen("calendar", "r", stdin)) {
290		if (doall)
291			return (NULL);
292		errx(1, "no calendar file.");
293	}
294	if (pipe(pdes) < 0)
295		return (NULL);
296	switch (vfork()) {
297	case -1:			/* error */
298		(void)close(pdes[0]);
299		(void)close(pdes[1]);
300		return (NULL);
301	case 0:
302		/* child -- stdin already setup, set stdout to pipe input */
303		if (pdes[1] != STDOUT_FILENO) {
304			(void)dup2(pdes[1], STDOUT_FILENO);
305			(void)close(pdes[1]);
306		}
307		(void)close(pdes[0]);
308		execl(_PATH_CPP, "cpp", "-P", "-I.", _PATH_INCLUDE, NULL);
309		(void)fprintf(stderr,
310		    "calendar: execl: %s: %s.\n", _PATH_CPP, strerror(errno));
311		_exit(1);
312	}
313	/* parent -- set stdin to pipe output */
314	(void)dup2(pdes[0], STDIN_FILENO);
315	(void)close(pdes[0]);
316	(void)close(pdes[1]);
317
318	/* not reading all calendar files, just set output to stdout */
319	if (!doall)
320		return (stdout);
321
322	/* set output to a temporary file, so if no output don't send mail */
323	(void)snprintf(path, sizeof(path), "%s/_calXXXXXX", _PATH_TMP);
324	if ((fd = mkstemp(path)) < 0)
325		return (NULL);
326	return (fdopen(fd, "w+"));
327}
328
329void
330closecal(fp)
331	FILE *fp;
332{
333	struct stat sbuf;
334	int nread, pdes[2], status;
335	char buf[1024];
336
337	if (!doall)
338		return;
339
340	(void)rewind(fp);
341	if (fstat(fileno(fp), &sbuf) || !sbuf.st_size)
342		goto done;
343	if (pipe(pdes) < 0)
344		goto done;
345	switch (vfork()) {
346	case -1:			/* error */
347		(void)close(pdes[0]);
348		(void)close(pdes[1]);
349		goto done;
350	case 0:
351		/* child -- set stdin to pipe output */
352		if (pdes[0] != STDIN_FILENO) {
353			(void)dup2(pdes[0], STDIN_FILENO);
354			(void)close(pdes[0]);
355		}
356		(void)close(pdes[1]);
357		execl(_PATH_SENDMAIL, "sendmail", "-i", "-t", "-F",
358		    "\"Reminder Service\"", "-f", "root", NULL);
359		(void)fprintf(stderr,
360		    "calendar: %s: %s.\n", _PATH_SENDMAIL, strerror(errno));
361		_exit(1);
362	}
363	/* parent -- write to pipe input */
364	(void)close(pdes[0]);
365
366	header[1].iov_base = header[3].iov_base = pw->pw_name;
367	header[1].iov_len = header[3].iov_len = strlen(pw->pw_name);
368	writev(pdes[1], header, 7);
369	while ((nread = read(fileno(fp), buf, sizeof(buf))) > 0)
370		(void)write(pdes[1], buf, nread);
371	(void)close(pdes[1]);
372done:	(void)fclose(fp);
373	(void)unlink(path);
374	while (wait(&status) >= 0);
375}
376
377static char *months[] = {
378	"jan", "feb", "mar", "apr", "may", "jun",
379	"jul", "aug", "sep", "oct", "nov", "dec", NULL,
380};
381
382int
383getmonth(s)
384	register char *s;
385{
386	register char **p;
387
388	for (p = months; *p; ++p)
389		if (!strncasecmp(s, *p, 3))
390			return ((p - months) + 1);
391	return (0);
392}
393
394static char *days[] = {
395	"sun", "mon", "tue", "wed", "thu", "fri", "sat", NULL,
396};
397
398int
399getday(s)
400	register char *s;
401{
402	register char **p;
403
404	for (p = days; *p; ++p)
405		if (!strncasecmp(s, *p, 3))
406			return ((p - days) + 1);
407	return (0);
408}
409
410void
411usage()
412{
413	(void)fprintf(stderr, "usage: calendar [-a]\n");
414	exit(1);
415}
416