usr.bin/calendar/calendar.c

   1 /*      $NetBSD: calendar.c,v 1.46 2008/07/21 14:19:21 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. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 __COPYRIGHT("@(#) Copyright (c) 1989, 1993\
  35  The Regents of the University of California.  All rights reserved.");
  36 #endif /* not lint */
  37
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "@(#)calendar.c  8.4 (Berkeley) 1/7/95";
  41 #endif
  42 __RCSID("$NetBSD: calendar.c,v 1.46 2008/07/21 14:19:21 lukem Exp $");
  43 #endif /* not lint */
  44
  45 #include <sys/param.h>
  46 #include <sys/time.h>
  47 #include <sys/stat.h>
  48 #include <sys/uio.h>
  49 #include <sys/wait.h>
  50
  51 #include <ctype.h>
  52 #include <err.h>
  53 #include <errno.h>
  54 #include <fcntl.h>
  55 #include <pwd.h>
  56 #include <stdbool.h>
  57 #include <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <time.h>
  61 #include <tzfile.h>
  62 #include <unistd.h>
  63
  64 #include "pathnames.h"
  65
  66 static unsigned short lookahead = 1;
  67 static unsigned short weekend = 2;
  68 static char *fname = NULL;
  69 static char *datestr = NULL;
  70 static const char *defaultnames[] = {"calendar", ".calendar", _PATH_SYSTEM_CALENDAR, NULL};
  71 static struct passwd *pw;
  72 static char path[MAXPATHLEN + 1];
  73 static bool doall = false;
  74 static bool cpp_restricted = false;
  75
  76 /* 1-based month, 0-based days, cumulative */
  77 static const int daytab[][14] = {
  78         { 0, -1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364 },
  79         { 0, -1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
  80 };
  81 static struct tm *tp;
  82 static const int *cumdays;
  83 static int offset, yrdays;
  84 static char dayname[10];
  85
  86 static struct iovec header[] = {
  87         { __UNCONST("From: "), 6 },
  88         { NULL, 0 },
  89         { __UNCONST(" (Reminder Service)\nTo: "), 24 },
  90         { NULL, 0 },
  91         { __UNCONST("\nSubject: "), 10 },
  92         { NULL, 0 },
  93         { __UNCONST("'s Calendar\nPrecedence: bulk\n\n"),  30 },
  94 };
  95
  96 static const char *days[] = {
  97         "sun", "mon", "tue", "wed", "thu", "fri", "sat", NULL,
  98 };
  99
 100 static const char *months[] = {
 101         "jan", "feb", "mar", "apr", "may", "jun",
 102         "jul", "aug", "sep", "oct", "nov", "dec", NULL,
 103 };
 104
 105 static void      atodays(int, char *, unsigned short *);
 106 static void      cal(void);
 107 static void      closecal(FILE *);
 108 static int       getday(char *);
 109 static int       getfield(char *, char **, int *);
 110 static void      getmmdd(struct tm *, char *);
 111 static int       getmonth(char *);
 112 static bool      isnow(char *);
 113 static FILE     *opencal(void);
 114 static void      settime(void);
 115 static void      usage(void) __dead;
 116
 117 int
 118 main(int argc, char **argv)
 119 {
 120         int ch;
 121         const char *caldir;
 122
 123         (void)setprogname(argv[0]);     /* for portability */
 124
 125         while ((ch = getopt(argc, argv, "-ad:f:l:w:x")) != -1) {
 126                 switch (ch) {
 127                 case '-':               /* backward contemptible */
 128                 case 'a':
 129                         if (getuid()) {
 130                                 errno = EPERM;
 131                                 err(EXIT_FAILURE, NULL);
 132                         }
 133                         doall = true;
 134                         break;
 135                 case 'd':
 136                         datestr = optarg;
 137                         break;
 138                 case 'f':
 139                         fname = optarg;
 140                         break;
 141                 case 'l':
 142                         atodays(ch, optarg, &lookahead);
 143                         break;
 144                 case 'w':
 145                         atodays(ch, optarg, &weekend);
 146                         break;
 147                 case 'x':
 148                         cpp_restricted = true;
 149                         break;
 150                 case '?':
 151                 default:
 152                         usage();
 153                 }
 154         }
 155         argc -= optind;
 156         argv += optind;
 157
 158         if (argc)
 159                 usage();
 160
 161         settime();
 162         if (doall) {
 163                 /*
 164                  * XXX - This ignores the user's CALENDAR_DIR variable.
 165                  *       Run under user's login shell?
 166                  */
 167                 while ((pw = getpwent()) != NULL) {
 168                         (void)setegid(pw->pw_gid);
 169                         (void)seteuid(pw->pw_uid);
 170                         if (chdir(pw->pw_dir) != -1)
 171                                 cal();
 172                         (void)seteuid(0);
 173                 }
 174         } else if ((caldir = getenv("CALENDAR_DIR")) != NULL) {
 175                 if (chdir(caldir) != -1)
 176                         cal();
 177         } else if ((pw = getpwuid(geteuid())) != NULL) {
 178                 if (chdir(pw->pw_dir) != -1)
 179                         cal();
 180         }
 181         return 0;
 182 }
 183
 184 static void
 185 cal(void)
 186 {
 187         bool printing;
 188         FILE *fp;
 189         char *line;
 190
 191         if ((fp = opencal()) == NULL)
 192                 return;
 193         printing = false;
 194         while ((line = fparseln(stdin,
 195                     NULL, NULL, NULL, FPARSELN_UNESCCOMM)) != NULL) {
 196                 if (line[0] == '\0')
 197                         continue;
 198                 if (line[0] != '\t')
 199                         printing = isnow(line);
 200                 if (printing)
 201                         (void)fprintf(fp, "%s\n", line);
 202                 free(line);
 203
 204         }
 205         closecal(fp);
 206 }
 207
 208 static void
 209 settime(void)
 210 {
 211         time_t now;
 212
 213         (void)time(&now);
 214         tp = localtime(&now);
 215         if (datestr)
 216                 getmmdd(tp, datestr);
 217
 218         if (isleap(tp->tm_year + TM_YEAR_BASE)) {
 219                 yrdays = DAYSPERLYEAR;
 220                 cumdays = daytab[1];
 221         } else {
 222                 yrdays = DAYSPERNYEAR;
 223                 cumdays = daytab[0];
 224         }
 225         /* Friday displays Monday's events */
 226         offset = tp->tm_wday == 5 ? lookahead + weekend : lookahead;
 227         header[5].iov_base = dayname;
 228         header[5].iov_len = strftime(dayname, sizeof(dayname), "%A", tp);
 229 }
 230
 231 /*
 232  * Possible date formats include any combination of:
 233  *      3-charmonth                     (January, Jan, Jan)
 234  *      3-charweekday                   (Friday, Monday, mon.)
 235  *      numeric month or day            (1, 2, 04)
 236  *
 237  * Any character may separate them, or they may not be separated.  Any line,
 238  * following a line that is matched, that starts with "whitespace", is shown
 239  * along with the matched line.
 240  */
 241 static bool
 242 isnow(char *endp)
 243 {
 244         int day;
 245         int flags;
 246         int month;
 247         int v1;
 248         int v2;
 249
 250 #define F_ISMONTH       0x01
 251 #define F_ISDAY         0x02
 252 #define F_WILDMONTH     0x04
 253 #define F_WILDDAY       0x08
 254
 255         flags = 0;
 256
 257         /* didn't recognize anything, skip it */
 258         if (!(v1 = getfield(endp, &endp, &flags)))
 259                 return false;
 260
 261         if (flags & F_ISDAY || v1 > 12) {
 262                 /* found a day */
 263                 day = v1;
 264                 /* if no recognizable month, assume wildcard ('*') month */
 265                 if ((month = getfield(endp, &endp, &flags)) == 0) {
 266                         flags |= F_ISMONTH | F_WILDMONTH;
 267                         month = tp->tm_mon + 1;
 268                 }
 269         } else if (flags & F_ISMONTH) {
 270                 month = v1;
 271                 /* if no recognizable day, assume the first */
 272                 if ((day = getfield(endp, &endp, &flags)) == 0)
 273                         day = 1;
 274         } else {
 275                 v2 = getfield(endp, &endp, &flags);
 276                 if (flags & F_ISMONTH) {
 277                         day = v1;
 278                         month = v2;
 279                 } else {
 280                         /* F_ISDAY set, v2 > 12, or no way to tell */
 281                         month = v1;
 282                         /* if no recognizable day, assume the first */
 283                         day = v2 ? v2 : 1;
 284                 }
 285         }
 286         /* if month is out of range, treat it as '*' */
 287         if (month < 1 || month > 12) {
 288                 flags |= F_ISMONTH | F_WILDMONTH;
 289                 month = tp->tm_mon + 1;
 290         }
 291
 292         if (flags & F_WILDMONTH && flags & F_WILDDAY)
 293                 return true;
 294
 295         if (flags & F_WILDMONTH && flags & F_ISDAY && day == tp->tm_mday)
 296                 return true;
 297
 298         if (flags & F_ISMONTH && flags & F_WILDDAY && month == tp->tm_mon + 1)
 299                 return true;
 300
 301         if (flags & F_ISDAY)
 302                 day = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
 303         day = cumdays[month] + day;
 304
 305         /* if today or today + offset days */
 306         if (day >= tp->tm_yday && day <= tp->tm_yday + offset)
 307                 return true;
 308
 309         /* if number of days left in this year + days to event in next year */
 310         if (yrdays - tp->tm_yday + day <= offset)
 311                 return true;
 312
 313         return false;
 314 }
 315
 316 static int
 317 getfield(char *p, char **endp, int *flags)
 318 {
 319         int val;
 320         char *start;
 321         char savech;
 322
 323 #define FLDCHAR(a) (*p != '\0' && !isdigit((unsigned char)*p) && \
 324     !isalpha((unsigned char)*p) && *p != '*')
 325
 326         for (/*EMPTY*/; FLDCHAR(*p); ++p)
 327                 continue;
 328         if (*p == '*') {                        /* `*' is current month */
 329                 if (!(*flags & F_ISMONTH)) {
 330                         *flags |= F_ISMONTH | F_WILDMONTH;
 331                         *endp = p + 1;
 332                         return tp->tm_mon + 1;
 333                 } else {
 334                         *flags |= F_ISDAY | F_WILDDAY;
 335                         *endp = p + 1;
 336                         return 1;
 337                 }
 338         }
 339         if (isdigit((unsigned char)*p)) {
 340                 val = (int)strtol(p, &p, 10);   /* if 0, it's failure */
 341                 for (/*EMPTY*/; FLDCHAR(*p); ++p)
 342                         continue;
 343                 *endp = p;
 344                 return val;
 345         }
 346         for (start = p; *p != '\0' && isalpha((unsigned char)*++p); /*EMPTY*/)
 347                 continue;
 348         savech = *p;
 349         *p = '\0';
 350         if ((val = getmonth(start)) != 0)
 351                 *flags |= F_ISMONTH;
 352         else if ((val = getday(start)) != 0)
 353                 *flags |= F_ISDAY;
 354         else {
 355                 *p = savech;
 356                 return 0;
 357         }
 358         for (*p = savech; FLDCHAR(*p); ++p)
 359                 continue;
 360         *endp = p;
 361         return val;
 362 }
 363
 364 static FILE *
 365 opencal(void)
 366 {
 367         int fd;
 368         int pdes[2];
 369         const char **name;
 370
 371         /* open up calendar file as stdin */
 372         if (fname == NULL) {
 373                 for (name = defaultnames; *name != NULL; name++) {
 374                         if (freopen(*name, "rf", stdin) == NULL)
 375                                 continue;
 376                         else
 377                                 break;
 378                 }
 379                 if (*name == NULL) {
 380                         if (doall)
 381                                 return NULL;
 382                         err(EXIT_FAILURE, "Cannot open calendar file");
 383                 }
 384         } else if (freopen(fname, "rf", stdin) == NULL) {
 385                 if (doall)
 386                         return NULL;
 387                 err(EXIT_FAILURE, "Cannot open `%s'", fname);
 388         }
 389
 390         if (pipe(pdes) == -1) {
 391                 warn("Cannot open pipe");
 392                 return NULL;
 393         }
 394
 395         switch (fork()) {
 396         case -1:
 397                 /* error */
 398                 (void)close(pdes[0]);
 399                 (void)close(pdes[1]);
 400                 return NULL;
 401         case 0:
 402                 /* child -- stdin already setup, set stdout to pipe input */
 403                 if (pdes[1] != STDOUT_FILENO) {
 404                         (void)dup2(pdes[1], STDOUT_FILENO);
 405                         (void)close(pdes[1]);
 406                 }
 407                 (void)close(pdes[0]);
 408                 /* tell CPP to only open regular files */
 409                 if(!cpp_restricted && setenv("CPP_RESTRICTED", "", 1) == -1)
 410                         err(EXIT_FAILURE, "Cannot restrict cpp");
 411                 cpp_restricted = true;
 412
 413                 (void)execl(_PATH_CPP, "cpp", "-traditional", "-P", "-I.",
 414                     "-I" _PATH_CALENDARS, NULL);
 415                 err(EXIT_FAILURE, "Cannot exec `%s'", _PATH_CPP);
 416                 /*NOTREACHED*/
 417         default:
 418                 /* parent -- set stdin to pipe output */
 419                 (void)dup2(pdes[0], STDIN_FILENO);
 420                 (void)close(pdes[0]);
 421                 (void)close(pdes[1]);
 422
 423                 /* not reading all calendar files, just set output to stdout */
 424                 if (!doall)
 425                         return stdout;
 426
 427                 /*
 428                  * Set output to a temporary file, so if no output
 429                  * don't send mail.
 430                  */
 431                 (void)snprintf(path, sizeof(path), "%s/_calXXXXXX", _PATH_TMP);
 432                 if ((fd = mkstemp(path)) == -1) {
 433                         warn("Cannot create temporary file");
 434                         return NULL;
 435                 }
 436                 return fdopen(fd, "w+");
 437         }
 438         /*NOTREACHED*/
 439 }
 440
 441 static void
 442 closecal(FILE *fp)
 443 {
 444         struct stat sbuf;
 445         ssize_t nread;
 446         int pdes[2];
 447         int status;
 448         char buf[1024];
 449
 450         if (!doall)
 451                 return;
 452
 453         (void)rewind(fp);
 454         if (fstat(fileno(fp), &sbuf) == -1 || sbuf.st_size == 0)
 455                 goto done;
 456         if (pipe(pdes) == -1)
 457                 goto done;
 458
 459         switch (fork()) {
 460         case -1:
 461                 /* error */
 462                 (void)close(pdes[0]);
 463                 (void)close(pdes[1]);
 464                 break;
 465         case 0:
 466                 /* child -- set stdin to pipe output */
 467                 if (pdes[0] != STDIN_FILENO) {
 468                         (void)dup2(pdes[0], STDIN_FILENO);
 469                         (void)close(pdes[0]);
 470                 }
 471                 (void)close(pdes[1]);
 472                 (void)execl(_PATH_SENDMAIL, "sendmail", "-i", "-t", "-F",
 473                     "\"Reminder Service\"", "-f", "root", NULL);
 474                 err(EXIT_FAILURE, "Cannot exec `%s'", _PATH_SENDMAIL);
 475                 /*NOTREACHED*/
 476         default:
 477                 /* parent -- write to pipe input */
 478                 (void)close(pdes[0]);
 479
 480                 header[1].iov_base = header[3].iov_base = (void *)pw->pw_name;
 481                 header[1].iov_len = header[3].iov_len = strlen(pw->pw_name);
 482                 (void)writev(pdes[1], header, 7);
 483                 while ((nread = read(fileno(fp), buf, sizeof(buf))) > 0)
 484                         (void)write(pdes[1], buf, (size_t)nread);
 485                 (void)close(pdes[1]);
 486                 break;
 487         }
 488
 489 done:   (void)fclose(fp);
 490         (void)unlink(path);
 491         while (wait(&status) != -1)
 492                 continue;
 493 }
 494
 495 static int
 496 getmonth(char *s)
 497 {
 498         const char **p;
 499
 500         for (p = months; *p; ++p)
 501                 if (strncasecmp(s, *p, 3) == 0)
 502                         return (int)(p - months) + 1;
 503         return 0;
 504 }
 505
 506 static int
 507 getday(char *s)
 508 {
 509         const char **p;
 510
 511         for (p = days; *p; ++p)
 512                 if (strncasecmp(s, *p, 3) == 0)
 513                         return (int)(p - days) + 1;
 514         return 0;
 515 }
 516
 517 static void
 518 atodays(int ch, char *arg, unsigned short *rvp)
 519 {
 520         int u;
 521
 522         u = atoi(arg);
 523         if (u < 0 || u > 366)
 524                 warnx("-%c %d out of range 0-366, ignored.", ch, u);
 525         else
 526                 *rvp = u;
 527 }
 528
 529 #define todigit(x) ((x) - '0')
 530 #define ATOI2(x) (todigit((x)[0]) * 10 + todigit((x)[1]))
 531 #define ISDIG2(x) (isdigit((unsigned char)(x)[0]) && isdigit((unsigned char)(x)[1]))
 532
 533 static void
 534 getmmdd(struct tm *ptm, char *ds)
 535 {
 536         bool ok = false;
 537         struct tm ttm;
 538
 539         ttm = *ptm;
 540         ttm.tm_isdst = -1;
 541
 542         if (ISDIG2(ds)) {
 543                 ttm.tm_mon = ATOI2(ds) - 1;
 544                 ds += 2;
 545         }
 546         if (ISDIG2(ds)) {
 547                 ttm.tm_mday = ATOI2(ds);
 548                 ds += 2;
 549                 ok = true;
 550         }
 551         if (ok) {
 552                 if (ISDIG2(ds) && ISDIG2(ds + 2)) {
 553                         ttm.tm_year = ATOI2(ds) * 100 - TM_YEAR_BASE;
 554                         ds += 2;
 555                         ttm.tm_year += ATOI2(ds);
 556                 } else if (ISDIG2(ds)) {
 557                         ttm.tm_year = ATOI2(ds);
 558                         if (ttm.tm_year < 69)
 559                                 ttm.tm_year += 2000 - TM_YEAR_BASE;
 560                         else
 561                                 ttm.tm_year += 1900 - TM_YEAR_BASE;
 562                 }
 563         }
 564         if (ok && mktime(&ttm) == -1)
 565                 ok = false;
 566
 567         if (ok)
 568                 *ptm = ttm;
 569         else {
 570                 warnx("Can't convert `%s' to date, ignored.", ds);
 571                 usage();
 572         }
 573 }
 574
 575 __dead
 576 static void
 577 usage(void)
 578 {
 579         (void)fprintf(stderr, "usage: %s [-ax] [-d MMDD[[YY]YY]"
 580             " [-f fname] [-l days] [-w days]\n", getprogname());
 581         exit(1);
 582 }