/* $OpenBSD: parsetime.c,v 1.12 2002/06/14 21:35:00 todd Exp $ */ /* $NetBSD: parsetime.c,v 1.3 1995/03/25 18:13:36 glass Exp $ */ /* * parsetime.c - parse time for at(1) * Copyright (C) 1993, 1994 Thomas Koenig * * modifications for english-language times * Copyright (C) 1993 David Parsons * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. The name of the author(s) may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * at [NOW] PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS * /NUMBER [DOT NUMBER] [AM|PM]\ /[MONTH NUMBER [NUMBER]] \ * |NOON | |[TOMORROW] | * |MIDNIGHT | |[DAY OF WEEK] | * \TEATIME / |NUMBER [SLASH NUMBER [SLASH NUMBER]]| * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ */ #include <sys/types.h> #include <err.h> #include <errno.h> #include <ctype.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> #include <tzfile.h> #include <unistd.h> #include "at.h" #include "panic.h" /* Structures and unions */ enum { /* symbols */ MIDNIGHT, NOON, TEATIME, PM, AM, TOMORROW, TODAY, NOW, MINUTES, HOURS, DAYS, WEEKS, NUMBER, PLUS, DOT, SLASH, ID, JUNK, JAN, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV, DEC, SUN, MON, TUE, WED, THU, FRI, SAT }; /* * parse translation table - table driven parsers can be your FRIEND! */ struct { char *name; /* token name */ int value; /* token id */ int plural; /* is this plural? */ } Specials[] = { { "midnight", MIDNIGHT, 0 }, /* 00:00:00 of today or tomorrow */ { "noon", NOON, 0 }, /* 12:00:00 of today or tomorrow */ { "teatime", TEATIME, 0 }, /* 16:00:00 of today or tomorrow */ { "am", AM, 0 }, /* morning times for 0-12 clock */ { "pm", PM, 0 }, /* evening times for 0-12 clock */ { "tomorrow", TOMORROW, 0 }, /* execute 24 hours from time */ { "today", TODAY, 0 }, /* execute today - don't advance time */ { "now", NOW, 0 }, /* opt prefix for PLUS */ { "minute", MINUTES, 0 }, /* minutes multiplier */ { "min", MINUTES, 0 }, { "m", MINUTES, 0 }, { "minutes", MINUTES, 1 }, /* (pluralized) */ { "hour", HOURS, 0 }, /* hours ... */ { "hr", HOURS, 0 }, /* abbreviated */ { "h", HOURS, 0 }, { "hours", HOURS, 1 }, /* (pluralized) */ { "day", DAYS, 0 }, /* days ... */ { "d", DAYS, 0 }, { "days", DAYS, 1 }, /* (pluralized) */ { "week", WEEKS, 0 }, /* week ... */ { "w", WEEKS, 0 }, { "weeks", WEEKS, 1 }, /* (pluralized) */ { "jan", JAN, 0 }, { "feb", FEB, 0 }, { "mar", MAR, 0 }, { "apr", APR, 0 }, { "may", MAY, 0 }, { "jun", JUN, 0 }, { "jul", JUL, 0 }, { "aug", AUG, 0 }, { "sep", SEP, 0 }, { "oct", OCT, 0 }, { "nov", NOV, 0 }, { "dec", DEC, 0 }, { "january", JAN,0 }, { "february", FEB,0 }, { "march", MAR,0 }, { "april", APR,0 }, { "may", MAY,0 }, { "june", JUN,0 }, { "july", JUL,0 }, { "august", AUG,0 }, { "september", SEP,0 }, { "october", OCT,0 }, { "november", NOV,0 }, { "december", DEC,0 }, { "sunday", SUN, 0 }, { "sun", SUN, 0 }, { "monday", MON, 0 }, { "mon", MON, 0 }, { "tuesday", TUE, 0 }, { "tue", TUE, 0 }, { "wednesday", WED, 0 }, { "wed", WED, 0 }, { "thursday", THU, 0 }, { "thu", THU, 0 }, { "friday", FRI, 0 }, { "fri", FRI, 0 }, { "saturday", SAT, 0 }, { "sat", SAT, 0 }, }; static char **scp; /* scanner - pointer at arglist */ static char scc; /* scanner - count of remaining arguments */ static char *sct; /* scanner - next char pointer in current argument */ static int need; /* scanner - need to advance to next argument */ static char *sc_token; /* scanner - token buffer */ static size_t sc_len; /* scanner - length of token buffer */ static int sc_tokid; /* scanner - token id */ static int sc_tokplur; /* scanner - is token plural? */ #ifndef lint static const char rcsid[] = "$OpenBSD: parsetime.c,v 1.12 2002/06/14 21:35:00 todd Exp $"; #endif /* * parse a token, checking if it's something special to us */ static int parse_token(char *arg) { int i; for (i=0; i < sizeof(Specials) / sizeof(Specials[0]); i++) { if (strcasecmp(Specials[i].name, arg) == 0) { sc_tokplur = Specials[i].plural; return (sc_tokid = Specials[i].value); } } /* not special - must be some random id */ return (ID); } /* * init_scanner() sets up the scanner to eat arguments */ static void init_scanner(int argc, char **argv) { scp = argv; scc = argc; need = 1; sc_len = 1; while (argc-- > 0) sc_len += strlen(*argv++); if ((sc_token = (char *) malloc(sc_len)) == NULL) panic("Insufficient virtual memory"); } /* * token() fetches a token from the input stream */ static int token(void) { int idx; for (;;) { (void)memset(sc_token, 0, sc_len); sc_tokid = EOF; sc_tokplur = 0; idx = 0; /* * if we need to read another argument, walk along the * argument list; when we fall off the arglist, we'll * just return EOF forever */ if (need) { if (scc < 1) return (sc_tokid); sct = *scp; scp++; scc--; need = 0; } /* * eat whitespace now - if we walk off the end of the argument, * we'll continue, which puts us up at the top of the while loop * to fetch the next argument in */ while (isspace(*sct)) ++sct; if (!*sct) { need = 1; continue; } /* * preserve the first character of the new token */ sc_token[0] = *sct++; /* * then see what it is */ if (isdigit(sc_token[0])) { while (isdigit(*sct)) sc_token[++idx] = *sct++; sc_token[++idx] = 0; return ((sc_tokid = NUMBER)); } else if (isalpha(sc_token[0])) { while (isalpha(*sct)) sc_token[++idx] = *sct++; sc_token[++idx] = 0; return (parse_token(sc_token)); } else if (sc_token[0] == ':' || sc_token[0] == '.') return ((sc_tokid = DOT)); else if (sc_token[0] == '+') return ((sc_tokid = PLUS)); else if (sc_token[0] == '/') return ((sc_tokid = SLASH)); else return ((sc_tokid = JUNK)); } } /* * plonk() gives an appropriate error message if a token is incorrect */ static void plonk(int tok) { panic((tok == EOF) ? "incomplete time" : "garbled time"); } /* * expect() gets a token and dies most horribly if it's not the token we want */ static void expect(int desired) { if (token() != desired) plonk(sc_tokid); /* and we die here... */ } /* * dateadd() adds a number of minutes to a date. It is extraordinarily * stupid regarding day-of-month overflow, and will most likely not * work properly */ static void dateadd(int minutes, struct tm *tm) { /* increment days */ while (minutes > 24*60) { minutes -= 24*60; tm->tm_mday++; } /* increment hours */ while (minutes > 60) { minutes -= 60; tm->tm_hour++; if (tm->tm_hour > 23) { tm->tm_mday++; tm->tm_hour = 0; } } /* increment minutes */ tm->tm_min += minutes; if (tm->tm_min > 59) { tm->tm_hour++; tm->tm_min -= 60; if (tm->tm_hour > 23) { tm->tm_mday++; tm->tm_hour = 0; } } } /* * plus() parses a now + time * * at [NOW] PLUS NUMBER [MINUTES|HOURS|DAYS|WEEKS] * */ static void plus(struct tm *tm) { int delay; int expectplur; expect(NUMBER); delay = atoi(sc_token); expectplur = (delay != 1) ? 1 : 0; switch (token()) { case WEEKS: delay *= 7; case DAYS: delay *= 24; case HOURS: delay *= 60; case MINUTES: if (expectplur != sc_tokplur) warnx("pluralization is wrong"); dateadd(delay, tm); return; } plonk(sc_tokid); } /* * tod() computes the time of day * [NUMBER [DOT NUMBER] [AM|PM]] */ static void tod(struct tm *tm) { int hour, minute = 0; size_t tlen; hour = atoi(sc_token); tlen = strlen(sc_token); /* * first pick out the time of day - if it's 4 digits, we assume * a HHMM time, otherwise it's HH DOT MM time */ if (token() == DOT) { expect(NUMBER); minute = atoi(sc_token); if (minute > 59) panic("garbled time"); token(); } else if (tlen == 4) { minute = hour % 100; if (minute > 59) panic("garbled time"); hour = hour / 100; } /* * check if an AM or PM specifier was given */ if (sc_tokid == AM || sc_tokid == PM) { if (hour > 12) panic("garbled time"); if (sc_tokid == PM) { if (hour != 12) /* 12:xx PM is 12:xx, not 24:xx */ hour += 12; } else { if (hour == 12) /* 12:xx AM is 00:xx, not 12:xx */ hour = 0; } token(); } else if (hour > 23) panic("garbled time"); /* * if we specify an absolute time, we don't want to bump the day even * if we've gone past that time - but if we're specifying a time plus * a relative offset, it's okay to bump things */ if ((sc_tokid == EOF || sc_tokid == PLUS) && tm->tm_hour > hour) { tm->tm_mday++; tm->tm_wday++; } tm->tm_hour = hour; tm->tm_min = minute; if (tm->tm_hour == 24) { tm->tm_hour = 0; tm->tm_mday++; } } /* * assign_date() assigns a date, wrapping to next year if needed */ static void assign_date(struct tm *tm, int mday, int mon, int year) { /* * Convert year into tm_year format (year - 1900). * We may be given the year in 2 digit, 4 digit, or tm_year format. */ if (year != -1) { if (year >= TM_YEAR_BASE) year -= TM_YEAR_BASE; /* convert from 4 digit year */ else if (year < 100) { /* Convert to tm_year assuming current century */ year += (tm->tm_year / 100) * 100; if (year == tm->tm_year - 1) year++; /* Common off by one error */ else if (year < tm->tm_year) year += 100; /* must be in next century */ } } if (year < 0 && (tm->tm_mon > mon ||(tm->tm_mon == mon && tm->tm_mday > mday))) year = tm->tm_year + 1; tm->tm_mday = mday; tm->tm_mon = mon; if (year >= 0) tm->tm_year = year; } /* * month() picks apart a month specification * * /[<month> NUMBER [NUMBER]] \ * |[TOMORROW] | * |[DAY OF WEEK] | * |NUMBER [SLASH NUMBER [SLASH NUMBER]]| * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ */ static void month(struct tm *tm) { int year = (-1); int mday, wday, mon; size_t tlen; switch (sc_tokid) { case PLUS: plus(tm); break; case TOMORROW: /* do something tomorrow */ tm->tm_mday++; tm->tm_wday++; case TODAY: /* force ourselves to stay in today - no further processing */ token(); break; case JAN: case FEB: case MAR: case APR: case MAY: case JUN: case JUL: case AUG: case SEP: case OCT: case NOV: case DEC: /* * do month mday [year] */ mon = sc_tokid - JAN; expect(NUMBER); mday = atoi(sc_token); if (token() == NUMBER) { year = atoi(sc_token); token(); } assign_date(tm, mday, mon, year); break; case SUN: case MON: case TUE: case WED: case THU: case FRI: case SAT: /* do a particular day of the week */ wday = sc_tokid - SUN; mday = tm->tm_mday; /* if this day is < today, then roll to next week */ if (wday < tm->tm_wday) mday += 7 - (tm->tm_wday - wday); else mday += (wday - tm->tm_wday); tm->tm_wday = wday; assign_date(tm, mday, tm->tm_mon, tm->tm_year); break; case NUMBER: /* * get numeric MMDDYY, mm/dd/yy, or dd.mm.yy */ tlen = strlen(sc_token); mon = atoi(sc_token); token(); if (sc_tokid == SLASH || sc_tokid == DOT) { int sep; sep = sc_tokid; expect(NUMBER); mday = atoi(sc_token); if (token() == sep) { expect(NUMBER); year = atoi(sc_token); token(); } /* * flip months and days for european timing */ if (sep == DOT) { int x = mday; mday = mon; mon = x; } } else if (tlen == 6 || tlen == 8) { if (tlen == 8) { year = (mon % 10000) - TM_YEAR_BASE; mon /= 10000; } else { year = mon % 100; mon /= 100; } mday = mon % 100; mon /= 100; } else panic("garbled time"); mon--; if (mon < 0 || mon > 11 || mday < 1 || mday > 31) panic("garbled time"); assign_date(tm, mday, mon, year); break; } /* case */ } time_t parsetime(int argc, char **argv) { /* * Do the argument parsing, die if necessary, and return the * time the job should be run. */ time_t nowtimer, runtimer; struct tm nowtime, runtime; int hr = 0; /* this MUST be initialized to zero for midnight/noon/teatime */ nowtimer = time(NULL); nowtime = *localtime(&nowtimer); runtime = nowtime; runtime.tm_sec = 0; runtime.tm_isdst = 0; if (argc == 0) usage(); init_scanner(argc, argv); switch (token()) { case NOW: /* now is optional prefix for PLUS tree */ token(); if (sc_tokid == EOF) { runtime = nowtime; break; } else if (sc_tokid != PLUS) plonk(sc_tokid); case PLUS: plus(&runtime); break; case NUMBER: tod(&runtime); month(&runtime); break; /* * evil coding for TEATIME|NOON|MIDNIGHT - we've initialised * hr to zero up above, then fall into this case in such a * way so we add +12 +4 hours to it for teatime, +12 hours * to it for noon, and nothing at all for midnight, then * set our runtime to that hour before leaping into the * month scanner */ case TEATIME: hr += 4; case NOON: hr += 12; case MIDNIGHT: if (runtime.tm_hour >= hr) { runtime.tm_mday++; runtime.tm_wday++; } runtime.tm_hour = hr; runtime.tm_min = 0; token(); /* fall through to month setting */ default: month(&runtime); break; } /* ugly case statement */ expect(EOF); /* * adjust for daylight savings time */ runtime.tm_isdst = -1; runtimer = mktime(&runtime); if (runtime.tm_isdst > 0) { runtimer -= 3600; runtimer = mktime(&runtime); } if (runtimer < 0) panic("garbled time"); if (nowtimer > runtimer) panic("Trying to travel back in time"); return (runtimer); }