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-rw-r--r--usr.bin/at/parsetime.c674
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diff --git a/usr.bin/at/parsetime.c b/usr.bin/at/parsetime.c
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+/*-
+ * parsetime.c - parse time for at(1)
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * 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/cdefs.h>
+/* System Headers */
+
+#include <sys/types.h>
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#ifndef __FreeBSD__
+#include <getopt.h>
+#endif
+
+/* Local headers */
+
+#include "at.h"
+#include "panic.h"
+#include "parsetime.h"
+
+
+/* Structures and unions */
+
+enum { /* symbols */
+ MIDNIGHT, NOON, TEATIME,
+ PM, AM, TOMORROW, TODAY, NOW,
+ MINUTES, HOURS, DAYS, WEEKS, MONTHS, YEARS,
+ NUMBER, PLUS, MINUS, 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!
+ */
+static const struct {
+ const 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 */
+ { "minutes", MINUTES,1 }, /* (pluralized) */
+ { "hour", HOURS,0 }, /* hours ... */
+ { "hours", HOURS,1 }, /* (pluralized) */
+ { "day", DAYS,0 }, /* days ... */
+ { "days", DAYS,1 }, /* (pluralized) */
+ { "week", WEEKS,0 }, /* week ... */
+ { "weeks", WEEKS,1 }, /* (pluralized) */
+ { "month", MONTHS,0 }, /* month ... */
+ { "months", MONTHS,1 }, /* (pluralized) */
+ { "year", YEARS,0 }, /* year ... */
+ { "years", YEARS,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 },
+} ;
+
+/* 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 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? */
+
+/* Local functions */
+
+/*
+ * parse a token, checking if it's something special to us
+ */
+static int
+parse_token(char *arg)
+{
+ size_t 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;
+} /* parse_token */
+
+
+/*
+ * 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 = malloc(sc_len)) == NULL)
+ errx(EXIT_FAILURE, "virtual memory exhausted");
+} /* init_scanner */
+
+/*
+ * token() fetches a token from the input stream
+ */
+static int
+token(void)
+{
+ int idx;
+
+ while (1) {
+ 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 = MINUS;
+ else if (sc_token[0] == '/')
+ return sc_tokid = SLASH;
+ else
+ return sc_tokid = JUNK;
+ } /* while (1) */
+} /* token */
+
+
+/*
+ * plonk() gives an appropriate error message if a token is incorrect
+ */
+static void
+plonk(int tok)
+{
+ panic((tok == EOF) ? "incomplete time"
+ : "garbled time");
+} /* plonk */
+
+
+/*
+ * 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... */
+} /* expect */
+
+
+/*
+ * plus_or_minus() holds functionality common to plus() and minus()
+ */
+static void
+plus_or_minus(struct tm *tm, int delay)
+{
+ int expectplur;
+
+ expectplur = (delay != 1 && delay != -1) ? 1 : 0;
+
+ switch (token()) {
+ case YEARS:
+ tm->tm_year += delay;
+ break;
+ case MONTHS:
+ tm->tm_mon += delay;
+ break;
+ case WEEKS:
+ delay *= 7;
+ 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) < 0)
+ plonk(sc_tokid);
+} /* plus_or_minus */
+
+
+/*
+ * plus() parses a now + time
+ *
+ * at [NOW] PLUS NUMBER [MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS]
+ *
+ */
+static void
+plus(struct tm *tm)
+{
+ int delay;
+
+ expect(NUMBER);
+
+ delay = atoi(sc_token);
+ plus_or_minus(tm, delay);
+} /* plus */
+
+
+/*
+ * minus() is like plus but can not be used with NOW
+ */
+static void
+minus(struct tm *tm)
+{
+ int delay;
+
+ expect(NUMBER);
+
+ delay = -atoi(sc_token);
+ plus_or_minus(tm, delay);
+} /* minus */
+
+
+/*
+ * tod() computes the time of day
+ * [NUMBER [DOT NUMBER] [AM|PM]]
+ */
+static void
+tod(struct tm *tm)
+{
+ int hour, minute = 0;
+ int 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 || sc_tokid == MINUS) &&
+ 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++;
+ }
+} /* tod */
+
+
+/*
+ * assign_date() assigns a date, wrapping to next year if needed
+ */
+static void
+assign_date(struct tm *tm, long mday, long mon, long 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 >= 1900)
+ year -= 1900; /* convert from 4 digit year */
+ else if (year < 100) {
+ /* convert from 2 digit year */
+ struct tm *lt;
+ time_t now;
+
+ time(&now);
+ lt = localtime(&now);
+
+ /* Convert to tm_year assuming current century */
+ year += (lt->tm_year / 100) * 100;
+
+ if (year == lt->tm_year - 1) year++;
+ else if (year < lt->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;
+} /* assign_date */
+
+
+/*
+ * 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)
+{
+ long year= (-1);
+ long mday = 0, wday, mon;
+ int tlen;
+
+ switch (sc_tokid) {
+ case PLUS:
+ plus(tm);
+ break;
+ case MINUS:
+ minus(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 = atol(sc_token);
+ if (token() == NUMBER) {
+ year = atol(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 = atol(sc_token);
+ token();
+
+ if (sc_tokid == SLASH || sc_tokid == DOT) {
+ int sep;
+
+ sep = sc_tokid;
+ expect(NUMBER);
+ mday = atol(sc_token);
+ if (token() == sep) {
+ expect(NUMBER);
+ year = atol(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) - 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;
+ } /* case */
+} /* month */
+
+
+/* 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;
+ runtime.tm_isdst = 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;
+
+ /* MINUS is different from PLUS in that NOW is not
+ * an optional prefix for it
+ */
+ case MINUS:
+ minus(&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;
+ token();
+ /* FALLTHROUGH to month setting */
+ default:
+ month(&runtime);
+ break;
+ } /* ugly case statement */
+ expect(EOF);
+
+ /* convert back to time_t
+ */
+ runtime.tm_isdst = -1;
+ runtimer = mktime(&runtime);
+
+ if (runtimer < 0)
+ panic("garbled time");
+
+ if (nowtimer > runtimer)
+ panic("trying to travel back in time");
+
+ return runtimer;
+} /* parsetime */
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-15 02:59:41 +0000