freebsd-dev/usr.sbin/newsyslog/ptimes.c
2003-10-04 02:24:47 +00:00

620 lines
16 KiB
C

/*-
* ------+---------+---------+---------+---------+---------+---------+---------*
* Initial version of parse8601 was originally added to newsyslog.c in
* FreeBSD on Jan 22, 1999 by Garrett Wollman <wollman@FreeBSD.org>.
* Initial version of parseDWM was originally added to newsyslog.c in
* FreeBSD on Apr 4, 2000 by Hellmuth Michaelis <hm@FreeBSD.org>.
*
* Copyright (c) 2003 - Garance Alistair Drosehn <gad@FreeBSD.org>.
* All rights reserved.
*
* 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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, WHETHER 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.
*
* The views and conclusions contained in the software and documentation
* are those of the authors and should not be interpreted as representing
* official policies, either expressed or implied, of the FreeBSD Project.
*
* ------+---------+---------+---------+---------+---------+---------+---------*
* This is intended to be a set of general-purpose routines to process times.
* Right now it probably still has a number of assumptions in it, such that
* it works fine for newsyslog but might not work for other uses.
* ------+---------+---------+---------+---------+---------+---------+---------*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "extern.h"
#define SECS_PER_HOUR 3600
/*
* Bit-values which indicate which components of time were specified
* by the string given to parse8601 or parseDWM. These are needed to
* calculate what time-in-the-future will match that string.
*/
#define TSPEC_YEAR 0x0001
#define TSPEC_MONTHOFYEAR 0x0002
#define TSPEC_LDAYOFMONTH 0x0004
#define TSPEC_DAYOFMONTH 0x0008
#define TSPEC_DAYOFWEEK 0x0010
#define TSPEC_HOUROFDAY 0x0020
#define TNYET_ADJ4DST -10 /* DST has "not yet" been adjusted */
struct ptime_data {
time_t basesecs; /* Base point for relative times */
time_t tsecs; /* Time in seconds */
struct tm basetm; /* Base Time expanded into fields */
struct tm tm; /* Time expanded into fields */
int did_adj4dst; /* Track calls to ptime_adjust4dst */
int parseopts; /* Options given for parsing */
int tmspec; /* Indicates which time fields had
* been specified by the user */
};
static int days_pmonth(int month, int year);
static int parse8601(struct ptime_data *ptime, const char *str);
static int parseDWM(struct ptime_data *ptime, const char *str);
/*
* Simple routine to calculate the number of days in a given month.
*/
static int
days_pmonth(int month, int year)
{
static const int mtab[] = {31, 28, 31, 30, 31, 30, 31, 31,
30, 31, 30, 31};
int ndays;
ndays = mtab[month];
if (month == 1) {
/*
* We are usually called with a 'tm-year' value
* (ie, the value = the number of years past 1900).
*/
if (year < 1900)
year += 1900;
if (year % 4 == 0) {
/*
* This is a leap year, as long as it is not a
* multiple of 100, or if it is a multiple of
* both 100 and 400.
*/
if (year % 100 != 0)
ndays++; /* not multiple of 100 */
else if (year % 400 == 0)
ndays++; /* is multiple of 100 and 400 */
}
}
return (ndays);
}
/*-
* Parse a limited subset of ISO 8601. The specific format is as follows:
*
* [CC[YY[MM[DD]]]][THH[MM[SS]]] (where `T' is the literal letter)
*
* We don't accept a timezone specification; missing fields (including timezone)
* are defaulted to the current date but time zero.
*/
static int
parse8601(struct ptime_data *ptime, const char *s)
{
char *t;
long l;
struct tm tm;
l = strtol(s, &t, 10);
if (l < 0 || l >= INT_MAX || (*t != '\0' && *t != 'T'))
return (-1);
/*
* Now t points either to the end of the string (if no time was
* provided) or to the letter `T' which separates date and time in
* ISO 8601. The pointer arithmetic is the same for either case.
*/
tm = ptime->tm;
ptime->tmspec = TSPEC_HOUROFDAY;
switch (t - s) {
case 8:
tm.tm_year = ((l / 1000000) - 19) * 100;
l = l % 1000000;
case 6:
ptime->tmspec |= TSPEC_YEAR;
tm.tm_year -= tm.tm_year % 100;
tm.tm_year += l / 10000;
l = l % 10000;
case 4:
ptime->tmspec |= TSPEC_MONTHOFYEAR;
tm.tm_mon = (l / 100) - 1;
l = l % 100;
case 2:
ptime->tmspec |= TSPEC_DAYOFMONTH;
tm.tm_mday = l;
case 0:
break;
default:
return (-1);
}
/* sanity check */
if (tm.tm_year < 70 || tm.tm_mon < 0 || tm.tm_mon > 12
|| tm.tm_mday < 1 || tm.tm_mday > 31)
return (-1);
if (*t != '\0') {
s = ++t;
l = strtol(s, &t, 10);
if (l < 0 || l >= INT_MAX || (*t != '\0' && !isspace(*t)))
return (-1);
switch (t - s) {
case 6:
tm.tm_sec = l % 100;
l /= 100;
case 4:
tm.tm_min = l % 100;
l /= 100;
case 2:
ptime->tmspec |= TSPEC_HOUROFDAY;
tm.tm_hour = l;
case 0:
break;
default:
return (-1);
}
/* sanity check */
if (tm.tm_sec < 0 || tm.tm_sec > 60 || tm.tm_min < 0
|| tm.tm_min > 59 || tm.tm_hour < 0 || tm.tm_hour > 23)
return (-1);
}
ptime->tm = tm;
return (0);
}
/*-
* Parse a cyclic time specification, the format is as follows:
*
* [Dhh] or [Wd[Dhh]] or [Mdd[Dhh]]
*
* to rotate a logfile cyclic at
*
* - every day (D) within a specific hour (hh) (hh = 0...23)
* - once a week (W) at a specific day (d) OR (d = 0..6, 0 = Sunday)
* - once a month (M) at a specific day (d) (d = 1..31,l|L)
*
* We don't accept a timezone specification; missing fields
* are defaulted to the current date but time zero.
*/
static int
parseDWM(struct ptime_data *ptime, const char *s)
{
int daysmon, Dseen, WMseen;
const char *endval;
char *tmp;
long l;
struct tm tm;
/* Save away the number of days in this month */
tm = ptime->tm;
daysmon = days_pmonth(tm.tm_mon, tm.tm_year);
WMseen = Dseen = 0;
ptime->tmspec = TSPEC_HOUROFDAY;
for (;;) {
endval = NULL;
switch (*s) {
case 'D':
if (Dseen)
return (-1);
Dseen++;
ptime->tmspec |= TSPEC_HOUROFDAY;
s++;
l = strtol(s, &tmp, 10);
if (l < 0 || l > 23)
return (-1);
endval = tmp;
tm.tm_hour = l;
break;
case 'W':
if (WMseen)
return (-1);
WMseen++;
ptime->tmspec |= TSPEC_DAYOFWEEK;
s++;
l = strtol(s, &tmp, 10);
if (l < 0 || l > 6)
return (-1);
endval = tmp;
if (l != tm.tm_wday) {
int save;
if (l < tm.tm_wday) {
save = 6 - tm.tm_wday;
save += (l + 1);
} else {
save = l - tm.tm_wday;
}
tm.tm_mday += save;
if (tm.tm_mday > daysmon) {
tm.tm_mon++;
tm.tm_mday = tm.tm_mday - daysmon;
}
}
break;
case 'M':
if (WMseen)
return (-1);
WMseen++;
ptime->tmspec |= TSPEC_DAYOFMONTH;
s++;
if (tolower(*s) == 'l') {
/* User wants the last day of the month. */
ptime->tmspec |= TSPEC_LDAYOFMONTH;
tm.tm_mday = daysmon;
endval = s + 1;
} else {
l = strtol(s, &tmp, 10);
if (l < 1 || l > 31)
return (-1);
if (l > daysmon)
return (-1);
endval = tmp;
tm.tm_mday = l;
}
break;
default:
return (-1);
break;
}
if (endval == NULL)
return (-1);
else if (*endval == '\0' || isspace(*endval))
break;
else
s = endval;
}
ptime->tm = tm;
return (0);
}
/*
* Initialize a new ptime-related data area.
*/
struct ptime_data *
ptime_init(const struct ptime_data *optsrc)
{
struct ptime_data *newdata;
newdata = malloc(sizeof(struct ptime_data));
if (optsrc != NULL) {
memcpy(newdata, optsrc, sizeof(struct ptime_data));
} else {
memset(newdata, '\0', sizeof(struct ptime_data));
newdata->did_adj4dst = TNYET_ADJ4DST;
}
return (newdata);
}
/*
* Adjust a given time if that time is in a different timezone than
* some other time.
*/
int
ptime_adjust4dst(struct ptime_data *ptime, const struct ptime_data *dstsrc)
{
struct ptime_data adjtime;
if (ptime == NULL)
return (-1);
/*
* Changes are not made to the given time until after all
* of the calculations have been successful.
*/
adjtime = *ptime;
/* Check to see if this adjustment was already made */
if ((adjtime.did_adj4dst != TNYET_ADJ4DST) &&
(adjtime.did_adj4dst == dstsrc->tm.tm_isdst))
return (0); /* yes, so don't make it twice */
/* See if daylight-saving has changed between the two times. */
if (dstsrc->tm.tm_isdst != adjtime.tm.tm_isdst) {
if (adjtime.tm.tm_isdst == 1)
adjtime.tsecs -= SECS_PER_HOUR;
else if (adjtime.tm.tm_isdst == 0)
adjtime.tsecs += SECS_PER_HOUR;
adjtime.tm = *(localtime(&adjtime.tsecs));
/* Remember that this adjustment has been made */
adjtime.did_adj4dst = dstsrc->tm.tm_isdst;
/*
* XXX - Should probably check to see if changing the
* hour also changed the value of is_dst. What
* should we do in that case?
*/
}
*ptime = adjtime;
return (0);
}
int
ptime_relparse(struct ptime_data *ptime, int parseopts, time_t basetime,
const char *str)
{
int dpm, pres;
struct tm temp_tm;
ptime->parseopts = parseopts;
ptime->basesecs = basetime;
ptime->basetm = *(localtime(&ptime->basesecs));
ptime->tm = ptime->basetm;
ptime->tm.tm_hour = ptime->tm.tm_min = ptime->tm.tm_sec = 0;
/*
* Call a routine which sets ptime.tm and ptime.tspecs based
* on the given string and parsing-options. Note that the
* routine should not call mktime to set ptime.tsecs.
*/
if (parseopts & PTM_PARSE_DWM)
pres = parseDWM(ptime, str);
else
pres = parse8601(ptime, str);
if (pres < 0) {
ptime->tsecs = (time_t)pres;
return (pres);
}
/*
* Before calling mktime, check to see if we ended up with a
* "day-of-month" that does not exist in the selected month.
* If we did call mktime with that info, then mktime will
* make it look like the user specifically requested a day
* in the following month (eg: Feb 31 turns into Mar 3rd).
*/
dpm = days_pmonth(ptime->tm.tm_mon, ptime->tm.tm_year);
if ((parseopts & PTM_PARSE_MATCHDOM) &&
(ptime->tmspec & TSPEC_DAYOFMONTH) &&
(ptime->tm.tm_mday> dpm)) {
/*
* ptime_nxtime() will want a ptime->tsecs value,
* but we need to avoid mktime resetting all the
* ptime->tm values.
*/
if (verbose && dbg_at_times > 1)
fprintf(stderr,
"\t-- dom fixed: %4d/%02d/%02d %02d:%02d (%02d)",
ptime->tm.tm_year, ptime->tm.tm_mon,
ptime->tm.tm_mday, ptime->tm.tm_hour,
ptime->tm.tm_min, dpm);
temp_tm = ptime->tm;
ptime->tsecs = mktime(&temp_tm);
if (ptime->tsecs > (time_t)-1)
ptimeset_nxtime(ptime);
if (verbose && dbg_at_times > 1)
fprintf(stderr,
" to: %4d/%02d/%02d %02d:%02d\n",
ptime->tm.tm_year, ptime->tm.tm_mon,
ptime->tm.tm_mday, ptime->tm.tm_hour,
ptime->tm.tm_min);
}
/*
* Convert the ptime.tm into standard time_t seconds. Check
* for invalid times, which includes things like the hour lost
* when switching from "standard time" to "daylight saving".
*/
ptime->tsecs = mktime(&ptime->tm);
if (ptime->tsecs == (time_t)-1) {
ptime->tsecs = (time_t)-2;
return (-2);
}
return (0);
}
int
ptime_free(struct ptime_data *ptime)
{
if (ptime == NULL)
return (-1);
free(ptime);
return (0);
}
/*
* Some trivial routines so ptime_data can remain a completely
* opaque type.
*/
const char *
ptimeget_ctime(const struct ptime_data *ptime)
{
if (ptime == NULL)
return ("Null time in ptimeget_ctime()\n");
return (ctime(&ptime->tsecs));
}
double
ptimeget_diff(const struct ptime_data *minuend, const struct
ptime_data *subtrahend)
{
/* Just like difftime(), we have no good error-return */
if (minuend == NULL || subtrahend == NULL)
return (0.0);
return (difftime(minuend->tsecs, subtrahend->tsecs));
}
time_t
ptimeget_secs(const struct ptime_data *ptime)
{
if (ptime == NULL)
return (-1);
return (ptime->tsecs);
}
/*
* Generate an approximate timestamp for the next event, based on
* what parts of time were specified by the original parameter to
* ptime_relparse(). The result may be -1 if there is no obvious
* "next time" which will work.
*/
int
ptimeset_nxtime(struct ptime_data *ptime)
{
int moredays, tdpm, tmon, tyear;
struct ptime_data nextmatch;
if (ptime == NULL)
return (-1);
/*
* Changes are not made to the given time until after all
* of the calculations have been successful.
*/
nextmatch = *ptime;
/*
* If the user specified a year and we're already past that
* time, then there will never be another one!
*/
if (ptime->tmspec & TSPEC_YEAR)
return (-1);
/*
* The caller gave us a time in the past. Calculate how much
* time is needed to go from that valid rotate time to the
* next valid rotate time. We only need to get to the nearest
* hour, because newsyslog is only run once per hour.
*/
moredays = 0;
if (ptime->tmspec & TSPEC_MONTHOFYEAR) {
/* Special case: Feb 29th does not happen every year. */
if (ptime->tm.tm_mon == 1 && ptime->tm.tm_mday == 29) {
nextmatch.tm.tm_year += 4;
if (days_pmonth(1, nextmatch.tm.tm_year) < 29)
nextmatch.tm.tm_year += 4;
} else {
nextmatch.tm.tm_year += 1;
}
nextmatch.tm.tm_isdst = -1;
nextmatch.tsecs = mktime(&nextmatch.tm);
} else if (ptime->tmspec & TSPEC_LDAYOFMONTH) {
/*
* Need to get to the last day of next month. Origtm is
* already at the last day of this month, so just add to
* it number of days in the next month.
*/
if (ptime->tm.tm_mon < 11)
moredays = days_pmonth(ptime->tm.tm_mon + 1,
ptime->tm.tm_year);
else
moredays = days_pmonth(0, ptime->tm.tm_year + 1);
} else if (ptime->tmspec & TSPEC_DAYOFMONTH) {
/* Jump to the same day in the next month */
moredays = days_pmonth(ptime->tm.tm_mon, ptime->tm.tm_year);
/*
* In some cases, the next month may not *have* the
* desired day-of-the-month. If that happens, then
* move to the next month that does have enough days.
*/
tmon = ptime->tm.tm_mon;
tyear = ptime->tm.tm_year;
for (;;) {
if (tmon < 11)
tmon += 1;
else {
tmon = 0;
tyear += 1;
}
tdpm = days_pmonth(tmon, tyear);
if (tdpm >= ptime->tm.tm_mday)
break;
moredays += tdpm;
}
} else if (ptime->tmspec & TSPEC_DAYOFWEEK) {
moredays = 7;
} else if (ptime->tmspec & TSPEC_HOUROFDAY) {
moredays = 1;
}
if (moredays != 0) {
nextmatch.tsecs += SECS_PER_HOUR * 24 * moredays;
nextmatch.tm = *(localtime(&nextmatch.tsecs));
}
/*
* The new time will need to be adjusted if the setting of
* daylight-saving has changed between the two times.
*/
ptime_adjust4dst(&nextmatch, ptime);
/* Everything worked. Update the given time and return. */
*ptime = nextmatch;
return (0);
}
int
ptimeset_time(struct ptime_data *ptime, time_t secs)
{
if (ptime == NULL)
return (-1);
ptime->tsecs = secs;
ptime->tm = *(localtime(&ptime->tsecs));
ptime->parseopts = 0;
/* ptime->tmspec = ? */
return (0);
}