xref: /netbsd-src/usr.bin/calendar/calendar.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: calendar.c,v 1.9 1997/06/20 08:11:34 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1989, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)calendar.c	8.4 (Berkeley) 1/7/95";
45 #endif
46 static char rcsid[] = "$NetBSD: calendar.c,v 1.9 1997/06/20 08:11:34 lukem Exp $";
47 #endif /* not lint */
48 
49 #include <sys/param.h>
50 #include <sys/time.h>
51 #include <sys/stat.h>
52 #include <sys/uio.h>
53 #include <sys/wait.h>
54 
55 #include <ctype.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <pwd.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <tzfile.h>
64 #include <unistd.h>
65 
66 #include "pathnames.h"
67 
68 struct passwd *pw;
69 int doall;
70 
71 void	 cal __P((void));
72 void	 closecal __P((FILE *));
73 int	 getday __P((char *));
74 int	 getfield __P((char *, char **, int *));
75 int	 getmonth __P((char *));
76 int	 isnow __P((char *));
77 FILE	*opencal __P((void));
78 void	 settime __P((void));
79 void	 usage __P((void));
80 
81 int
82 main(argc, argv)
83 	int argc;
84 	char *argv[];
85 {
86 	extern int optind;
87 	int ch;
88 	char *caldir;
89 
90 	while ((ch = getopt(argc, argv, "-a")) != EOF)
91 		switch (ch) {
92 		case '-':		/* backward contemptible */
93 		case 'a':
94 			if (getuid()) {
95 				errno = EPERM;
96 				err(1, NULL);
97 			}
98 			doall = 1;
99 			break;
100 		case '?':
101 		default:
102 			usage();
103 		}
104 	argc -= optind;
105 	argv += optind;
106 
107 	if (argc)
108 		usage();
109 
110 	settime();
111 	if (doall)
112 		while ((pw = getpwent()) != NULL) {
113 			(void)setegid(pw->pw_gid);
114 			(void)seteuid(pw->pw_uid);
115 			if (!chdir(pw->pw_dir))
116 				cal();
117 			(void)seteuid(0);
118 		}
119 	else if ((caldir = getenv("CALENDAR_DIR")) != NULL) {
120 			if(!chdir(caldir))
121 				cal();
122 	} else
123 		cal();
124 	exit(0);
125 }
126 
127 void
128 cal()
129 {
130 	register int printing;
131 	register char *p;
132 	FILE *fp;
133 	int ch;
134 	char buf[2048 + 1];
135 
136 	if ((fp = opencal()) == NULL)
137 		return;
138 	for (printing = 0; fgets(buf, sizeof(buf), stdin) != NULL;) {
139 		if ((p = strchr(buf, '\n')) != NULL)
140 			*p = '\0';
141 		else
142 			while ((ch = getchar()) != '\n' && ch != EOF);
143 		if (buf[0] == '\0')
144 			continue;
145 		if (buf[0] != '\t')
146 			printing = isnow(buf) ? 1 : 0;
147 		if (printing)
148 			(void)fprintf(fp, "%s\n", buf);
149 	}
150 	closecal(fp);
151 }
152 
153 struct iovec header[] = {
154 	"From: ", 6,
155 	NULL, 0,
156 	" (Reminder Service)\nTo: ", 24,
157 	NULL, 0,
158 	"\nSubject: ", 10,
159 	NULL, 0,
160 	"'s Calendar\nPrecedence: bulk\n\n",  30,
161 };
162 
163 /* 1-based month, 0-based days, cumulative */
164 int daytab[][14] = {
165 	0, -1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364,
166 	0, -1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365,
167 };
168 struct tm *tp;
169 int *cumdays, offset, yrdays;
170 char dayname[10];
171 
172 void
173 settime()
174 {
175 	time_t now;
176 
177 	(void)time(&now);
178 	tp = localtime(&now);
179 	if (isleap(tp->tm_year + 1900)) {
180 		yrdays = DAYSPERLYEAR;
181 		cumdays = daytab[1];
182 	} else {
183 		yrdays = DAYSPERNYEAR;
184 		cumdays = daytab[0];
185 	}
186 	/* Friday displays Monday's events */
187 	offset = tp->tm_wday == 5 ? 3 : 1;
188 	header[5].iov_base = dayname;
189 	header[5].iov_len = strftime(dayname, sizeof(dayname), "%A", tp);
190 }
191 
192 /*
193  * Possible date formats include any combination of:
194  *	3-charmonth			(January, Jan, Jan)
195  *	3-charweekday			(Friday, Monday, mon.)
196  *	numeric month or day		(1, 2, 04)
197  *
198  * Any character may separate them, or they may not be separated.  Any line,
199  * following a line that is matched, that starts with "whitespace", is shown
200  * along with the matched line.
201  */
202 int
203 isnow(endp)
204 	char *endp;
205 {
206 	int day, flags, month, v1, v2;
207 
208 #define	F_ISMONTH	0x01
209 #define	F_ISDAY		0x02
210 	flags = 0;
211 	/* didn't recognize anything, skip it */
212 	if (!(v1 = getfield(endp, &endp, &flags)))
213 		return (0);
214 	if (flags & F_ISDAY || v1 > 12) {
215 		/* found a day */
216 		day = v1;
217 		month = tp->tm_mon + 1;
218 	} else if (flags & F_ISMONTH) {
219 		month = v1;
220 		/* if no recognizable day, assume the first */
221 		if (!(day = getfield(endp, &endp, &flags)))
222 			day = 1;
223 	} else {
224 		v2 = getfield(endp, &endp, &flags);
225 		if (flags & F_ISMONTH) {
226 			day = v1;
227 			month = v2;
228 		} else {
229 			/* F_ISDAY set, v2 > 12, or no way to tell */
230 			month = v1;
231 			/* if no recognizable day, assume the first */
232 			day = v2 ? v2 : 1;
233 		}
234 	}
235 	if (flags & F_ISDAY)
236 		day = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
237 	day = cumdays[month] + day;
238 
239 	/* if today or today + offset days */
240 	if (day >= tp->tm_yday && day <= tp->tm_yday + offset)
241 		return (1);
242 	/* if number of days left in this year + days to event in next year */
243 	if (yrdays - tp->tm_yday + day <= offset)
244 		return (1);
245 	return (0);
246 }
247 
248 int
249 getfield(p, endp, flags)
250 	char *p, **endp;
251 	int *flags;
252 {
253 	int val;
254 	char *start, savech;
255 
256 	for (; *p != '\0' && !isdigit(*p) && !isalpha(*p) && *p != '*'; ++p)
257 		;
258 	if (*p == '*') {			/* `*' is current month */
259 		*flags |= F_ISMONTH;
260 		*endp = p+1;
261 		return (tp->tm_mon + 1);
262 	}
263 	if (isdigit(*p)) {
264 		val = strtol(p, &p, 10);	/* if 0, it's failure */
265 		for (; *p != '\0' && !isdigit(*p) && !isalpha(*p) && *p != '*';
266 		    ++p)
267 			;
268 		*endp = p;
269 		return (val);
270 	}
271 	for (start = p; *p != '\0' && isalpha(*++p);)
272 		;
273 	savech = *p;
274 	*p = '\0';
275 	if ((val = getmonth(start)) != 0)
276 		*flags |= F_ISMONTH;
277 	else if ((val = getday(start)) != 0)
278 		*flags |= F_ISDAY;
279 	else {
280 		*p = savech;
281 		return (0);
282 	}
283 	for (*p = savech;
284 	    *p != '\0' && !isdigit(*p) && !isalpha(*p) && *p != '*';
285 	    ++p)
286 		;
287 	*endp = p;
288 	return (val);
289 }
290 
291 char path[MAXPATHLEN + 1];
292 
293 FILE *
294 opencal()
295 {
296 	int fd, pdes[2];
297 
298 	/* open up calendar file as stdin */
299 	if (!freopen("calendar", "r", stdin)) {
300 		if (doall)
301 			return (NULL);
302 		errx(1, "no calendar file.");
303 	}
304 	if (pipe(pdes) < 0)
305 		return (NULL);
306 	switch (vfork()) {
307 	case -1:			/* error */
308 		(void)close(pdes[0]);
309 		(void)close(pdes[1]);
310 		return (NULL);
311 	case 0:
312 		/* child -- stdin already setup, set stdout to pipe input */
313 		if (pdes[1] != STDOUT_FILENO) {
314 			(void)dup2(pdes[1], STDOUT_FILENO);
315 			(void)close(pdes[1]);
316 		}
317 		(void)close(pdes[0]);
318 		execl(_PATH_CPP, "cpp", "-P", "-I.", _PATH_INCLUDE, NULL);
319 		warn("execl: %s", _PATH_CPP);
320 		_exit(1);
321 	}
322 	/* parent -- set stdin to pipe output */
323 	(void)dup2(pdes[0], STDIN_FILENO);
324 	(void)close(pdes[0]);
325 	(void)close(pdes[1]);
326 
327 	/* not reading all calendar files, just set output to stdout */
328 	if (!doall)
329 		return (stdout);
330 
331 	/* set output to a temporary file, so if no output don't send mail */
332 	(void)snprintf(path, sizeof(path), "%s/_calXXXXXX", _PATH_TMP);
333 	if ((fd = mkstemp(path)) < 0)
334 		return (NULL);
335 	return (fdopen(fd, "w+"));
336 }
337 
338 void
339 closecal(fp)
340 	FILE *fp;
341 {
342 	struct stat sbuf;
343 	int nread, pdes[2], status;
344 	char buf[1024];
345 
346 	if (!doall)
347 		return;
348 
349 	(void)rewind(fp);
350 	if (fstat(fileno(fp), &sbuf) || !sbuf.st_size)
351 		goto done;
352 	if (pipe(pdes) < 0)
353 		goto done;
354 	switch (vfork()) {
355 	case -1:			/* error */
356 		(void)close(pdes[0]);
357 		(void)close(pdes[1]);
358 		goto done;
359 	case 0:
360 		/* child -- set stdin to pipe output */
361 		if (pdes[0] != STDIN_FILENO) {
362 			(void)dup2(pdes[0], STDIN_FILENO);
363 			(void)close(pdes[0]);
364 		}
365 		(void)close(pdes[1]);
366 		execl(_PATH_SENDMAIL, "sendmail", "-i", "-t", "-F",
367 		    "\"Reminder Service\"", "-f", "root", NULL);
368 		warn("execl: %s", _PATH_SENDMAIL);
369 		_exit(1);
370 	}
371 	/* parent -- write to pipe input */
372 	(void)close(pdes[0]);
373 
374 	header[1].iov_base = header[3].iov_base = pw->pw_name;
375 	header[1].iov_len = header[3].iov_len = strlen(pw->pw_name);
376 	writev(pdes[1], header, 7);
377 	while ((nread = read(fileno(fp), buf, sizeof(buf))) > 0)
378 		(void)write(pdes[1], buf, nread);
379 	(void)close(pdes[1]);
380 done:	(void)fclose(fp);
381 	(void)unlink(path);
382 	while (wait(&status) >= 0);
383 }
384 
385 static char *months[] = {
386 	"jan", "feb", "mar", "apr", "may", "jun",
387 	"jul", "aug", "sep", "oct", "nov", "dec", NULL,
388 };
389 
390 int
391 getmonth(s)
392 	register char *s;
393 {
394 	register char **p;
395 
396 	for (p = months; *p; ++p)
397 		if (!strncasecmp(s, *p, 3))
398 			return ((p - months) + 1);
399 	return (0);
400 }
401 
402 static char *days[] = {
403 	"sun", "mon", "tue", "wed", "thu", "fri", "sat", NULL,
404 };
405 
406 int
407 getday(s)
408 	register char *s;
409 {
410 	register char **p;
411 
412 	for (p = days; *p; ++p)
413 		if (!strncasecmp(s, *p, 3))
414 			return ((p - days) + 1);
415 	return (0);
416 }
417 
418 void
419 usage()
420 {
421 	(void)fprintf(stderr, "usage: calendar [-a]\n");
422 	exit(1);
423 }
424