diff options
Diffstat (limited to 'usr.bin/at/parsetime.c')
-rw-r--r-- | usr.bin/at/parsetime.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/usr.bin/at/parsetime.c b/usr.bin/at/parsetime.c new file mode 100644 index 0000000..5b1cc15 --- /dev/null +++ b/usr.bin/at/parsetime.c @@ -0,0 +1,652 @@ +/* $NetBSD: parsetime.c,v 1.19 2009/01/18 01:02:31 lukem 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/ + */ + +/* System Headers */ + +#include <sys/types.h> +#include <err.h> +#include <ctype.h> +#include <errno.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <tzfile.h> +#include <unistd.h> + +/* Local headers */ + +#include "at.h" +#include "panic.h" +#include "parsetime.h" +#include "stime.h" + +/* Structures and unions */ + +typedef enum { /* symbols */ + MIDNIGHT, NOON, TEATIME, + PM, AM, TOMORROW, TODAY, NOW, + MINUTES, HOURS, DAYS, WEEKS, MONTHS, YEARS, + 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, + TOKEOF /* EOF marker */ +} tokid_t; + +/* + * parse translation table - table driven parsers can be your FRIEND! + */ +static const struct { + const char *name; /* token name */ + tokid_t value; /* token id */ + bool plural; /* is this plural? */ +} Specials[] = { + {"midnight", MIDNIGHT, false}, /* 00:00:00 of today or tomorrow */ + {"noon", NOON, false}, /* 12:00:00 of today or tomorrow */ + {"teatime", TEATIME, false}, /* 16:00:00 of today or tomorrow */ + {"am", AM, false}, /* morning times for 0-12 clock */ + {"pm", PM, false}, /* evening times for 0-12 clock */ + {"tomorrow", TOMORROW, false}, /* execute 24 hours from time */ + {"today", TODAY, false}, /* execute today - don't advance time */ + {"now", NOW, false}, /* opt prefix for PLUS */ + + {"minute", MINUTES, false}, /* minutes multiplier */ + {"min", MINUTES, false}, + {"m", MINUTES, false}, + {"minutes", MINUTES, true}, /* (pluralized) */ + {"hour", HOURS, false}, /* hours ... */ + {"hr", HOURS, false}, /* abbreviated */ + {"h", HOURS, false}, + {"hours", HOURS, true}, /* (pluralized) */ + {"day", DAYS, false}, /* days ... */ + {"d", DAYS, false}, + {"days", DAYS, true}, /* (pluralized) */ + {"week", WEEKS, false}, /* week ... */ + {"w", WEEKS, false}, + {"weeks", WEEKS, true}, /* (pluralized) */ + { "month", MONTHS, 0 }, /* month ... */ + { "months", MONTHS, 1 }, /* (pluralized) */ + { "year", YEARS, 0 }, /* year ... */ + { "years", YEARS, 1 }, /* (pluralized) */ + {"jan", JAN, false}, + {"feb", FEB, false}, + {"mar", MAR, false}, + {"apr", APR, false}, + {"may", MAY, false}, + {"jun", JUN, false}, + {"jul", JUL, false}, + {"aug", AUG, false}, + {"sep", SEP, false}, + {"oct", OCT, false}, + {"nov", NOV, false}, + {"dec", DEC, false}, + {"january", JAN, false}, + {"february", FEB, false}, + {"march", MAR, false}, + {"april", APR, false}, + {"may", MAY, false}, + {"june", JUN, false}, + {"july", JUL, false}, + {"august", AUG, false}, + {"september", SEP, false}, + {"october", OCT, false}, + {"november", NOV, false}, + {"december", DEC, false}, + {"sunday", SUN, false}, + {"sun", SUN, false}, + {"monday", MON, false}, + {"mon", MON, false}, + {"tuesday", TUE, false}, + {"tue", TUE, false}, + {"wednesday", WED, false}, + {"wed", WED, false}, + {"thursday", THU, false}, + {"thu", THU, false}, + {"friday", FRI, false}, + {"fri", FRI, false}, + {"saturday", SAT, false}, + {"sat", SAT, false} +}; + +/* File scope variables */ + +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 bool 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 tokid_t sc_tokid;/* scanner - token id */ +static bool sc_tokplur; /* scanner - is token plural? */ + +#ifndef lint +#if 0 +static char rcsid[] = "$OpenBSD: parsetime.c,v 1.4 1997/03/01 23:40:10 millert Exp $"; +#else +__RCSID("$NetBSD: parsetime.c,v 1.19 2009/01/18 01:02:31 lukem Exp $"); +#endif +#endif + +/* Local functions */ +static void assign_date(struct tm *, int, int, int); +static void expect(tokid_t); +static void init_scanner(int, char **); +static void month(struct tm *); +static tokid_t parse_token(char *); +static void plonk(tokid_t) __dead; +static void plus(struct tm *); +static void tod(struct tm *); +static tokid_t token(void); + +/* + * parse a token, checking if it's something special to us + */ +static tokid_t +parse_token(char *arg) +{ + size_t i; + + for (i=0; i < __arraycount(Specials); 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 = true; + sc_len = 1; + while (argc-- > 0) + sc_len += strlen(*argv++); + + if ((sc_token = malloc(sc_len)) == NULL) + panic("Insufficient virtual memory"); +} + +/* + * token() fetches a token from the input stream + */ +static tokid_t +token(void) +{ + int idx; + + for(;;) { + (void)memset(sc_token, 0, sc_len); + sc_tokid = TOKEOF; + sc_tokplur = false; + idx = 0; + + /* + * if we need to read another argument, walk along the + * argument list; when we fall off the arglist, we'll + * just return TOKEOF forever + */ + if (need) { + if (scc < 1) + return sc_tokid; + sct = *scp; + scp++; + scc--; + need = false; + } + /* + * 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((unsigned char)*sct)) + ++sct; + if (!*sct) { + need = true; + continue; + } + + /* + * preserve the first character of the new token + */ + sc_token[0] = *sct++; + + /* + * then see what it is + */ + if (isdigit((unsigned char)sc_token[0])) { + while (isdigit((unsigned char)*sct)) + sc_token[++idx] = *sct++; + sc_token[++idx] = 0; + return sc_tokid = NUMBER; + } else if (isalpha((unsigned char)sc_token[0])) { + while (isalpha((unsigned char)*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 + */ +__dead +static void +plonk(tokid_t tok) +{ + + panic(tok == TOKEOF ? "incomplete time" : "garbled time"); +} + +/* + * expect() gets a token and dies most horribly if it's not the token we want + */ +static void +expect(tokid_t desired) +{ + + if (token() != desired) + plonk(sc_tokid); /* and we die here... */ +} + +/* + * plus() parses a now + time + * + * at [NOW] PLUS NUMBER [MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS] + * + */ +static void +plus(struct tm *tm) +{ + int delay; + int expectplur; + + expect(NUMBER); + + delay = atoi(sc_token); + expectplur = delay != 1; + + switch (token()) { + case YEARS: + tm->tm_year += delay; + break; + case MONTHS: + tm->tm_mon += delay; + break; + case WEEKS: + delay *= 7; + /*FALLTHROUGH*/ + case DAYS: + tm->tm_mday += delay; + break; + case HOURS: + tm->tm_hour += delay; + break; + case MINUTES: + tm->tm_min += delay; + break; + default: + plonk(sc_tokid); + break; + } + + if (expectplur != sc_tokplur) + warnx("pluralization is wrong"); + + tm->tm_isdst = -1; + if (mktime(tm) == -1) + plonk(sc_tokid); +} + +/* + * tod() computes the time of day + * [NUMBER [DOT NUMBER] [AM|PM]] + */ +static void +tod(struct tm *tm) +{ + int hour, minute; + size_t tlen; + + minute = 0; + 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); + (void)token(); + } else if (tlen == 4) { + minute = hour % 100; + hour = hour / 100; + } + + if (minute > 59) + panic("garbled time"); + + /* + * 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; + } + (void)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 == TOKEOF || sc_tokid == PLUS) && tm->tm_hour > hour) { + tm->tm_mday++; + tm->tm_wday++; + } + + tm->tm_hour = hour; + tm->tm_min = minute; +} + +/* + * assign_date() assigns a date, wrapping to next year if needed. + * Accept years in 4-digit, 2-digit, or current year (-1). + */ +static void +assign_date(struct tm *tm, int mday, int mon, int year) +{ + + if (year > 99) { /* four digit year */ + if (year >= TM_YEAR_BASE) + tm->tm_year = year - TM_YEAR_BASE; + else + panic("garbled time"); + } + else if (year >= 0) { /* two digit year */ + tm->tm_year = conv_2dig_year(year) - TM_YEAR_BASE; + } + else if (year == -1) { /* year not given (use default in tm) */ + /* allow for 1 year range from current date */ + if (tm->tm_mon > mon || + (tm->tm_mon == mon && tm->tm_mday > mday)) + tm->tm_year++; + } + else + panic("invalid year"); + + tm->tm_mday = mday; + tm->tm_mon = mon; +} + +/* + * 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; + int mday, wday, mon; + size_t tlen; + + year = -1; + mday = 0; + switch (sc_tokid) { + case PLUS: + plus(tm); + break; + + case TOMORROW: + /* do something tomorrow */ + tm->tm_mday++; + tm->tm_wday++; + /*FALLTHROUGH*/ + case TODAY: + /* force ourselves to stay in today - no further processing */ + (void)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); + (void)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 + TM_YEAR_BASE); + break; + + case NUMBER: + /* + * get numeric MMDDYY, mm/dd/yy, or dd.mm.yy + */ + tlen = strlen(sc_token); + mon = atoi(sc_token); + (void)token(); + + if (sc_tokid == SLASH || sc_tokid == DOT) { + tokid_t sep; + + sep = sc_tokid; + expect(NUMBER); + mday = atoi(sc_token); + if (token() == sep) { + expect(NUMBER); + year = atoi(sc_token); + (void)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) - 1900; + 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; + default: + /* plonk(sc_tokid); */ /* XXX - die here? */ + break; + } +} + + +/* Global functions */ + +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; + + if (argc <= optind) + usage(); + + init_scanner(argc - optind, argv + optind); + + switch (token()) { + case NOW: + if (scc < 1) + return nowtimer; + + /* now is optional prefix for PLUS tree */ + expect(PLUS); + /*FALLTHROUGH*/ + 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; + /*FALLTHROUGH*/ + case NOON: + hr += 12; + /*FALLTHROUGH*/ + case MIDNIGHT: + if (runtime.tm_hour >= hr) { + runtime.tm_mday++; + runtime.tm_wday++; + } + runtime.tm_hour = hr; + runtime.tm_min = 0; + (void)token(); + /*FALLTHROUGH*/ /* fall through to month setting */ + default: + month(&runtime); + break; + } + expect(TOKEOF); + + /* + * adjust for daylight savings time + */ + runtime.tm_isdst = -1; + runtimer = mktime(&runtime); + + if (runtimer == (time_t)-1) + panic("Invalid time"); + + if (nowtimer > runtimer) + panic("Trying to travel back in time"); + + return runtimer; +} |