nagiosplugins
1.4.16

#include <config.h>
#include <time.h>
#include <limits.h>
#include <string.h>
#include "mktimeinternal.h"
Go to the source code of this file.
Defines  
#define  LEAP_SECONDS_POSSIBLE 1 
#define  SHR(a, b) 
#define  TYPE_IS_INTEGER(t) ((t) 1.5 == 1) 
#define  TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) 1) 
#define  TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0) 
#define  TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) 1) 
#define  TYPE_SIGNED(t) (! ((t) 0 < (t) 1)) 
#define  TYPE_MINIMUM(t) 
#define  TYPE_MAXIMUM(t) 
#define  TIME_T_MIN TYPE_MINIMUM (time_t) 
#define  TIME_T_MAX TYPE_MAXIMUM (time_t) 
#define  TIME_T_MIDPOINT (SHR (TIME_T_MIN + TIME_T_MAX, 1) + 1) 
#define  verify(name, assertion) struct name { char a[(assertion) ? 1 : 1]; } 
#define  EPOCH_YEAR 1970 
#define  TM_YEAR_BASE 1900 
#define  __localtime_r localtime_r 
#define  __mktime_internal mktime_internal 
Functions  
verify (time_t_is_integer, TYPE_IS_INTEGER(time_t))  
verify (twos_complement_arithmetic, TYPE_TWOS_COMPLEMENT(int))  
verify (base_year_is_a_multiple_of_100, TM_YEAR_BASE% 100==0)  
static int  leapyear (long int year) 
static time_t  ydhms_diff (long int year1, long int yday1, int hour1, int min1, int sec1, int year0, int yday0, int hour0, int min0, int sec0) 
static time_t  guess_time_tm (long int year, long int yday, int hour, int min, int sec, const time_t *t, const struct tm *tp) 
static struct tm *  ranged_convert (struct tm *(*convert)(const time_t *, struct tm *), time_t *t, struct tm *tp) 
time_t  __mktime_internal (struct tm *tp, struct tm *(*convert)(const time_t *, struct tm *), time_t *offset) 
time_t  mktime (struct tm *tp) 
Variables  
static const unsigned short int  __mon_yday [2][13] 
static time_t  localtime_offset 
#define __localtime_r localtime_r 
#define __mktime_internal mktime_internal 
#define EPOCH_YEAR 1970 
#define LEAP_SECONDS_POSSIBLE 1 
#define SHR  (  a,  
b  
) 
#define TIME_T_MAX TYPE_MAXIMUM (time_t) 
#define TIME_T_MIDPOINT (SHR (TIME_T_MIN + TIME_T_MAX, 1) + 1) 
#define TIME_T_MIN TYPE_MINIMUM (time_t) 
#define TM_YEAR_BASE 1900 
#define TYPE_IS_INTEGER  (  t  )  ((t) 1.5 == 1) 
#define TYPE_MAXIMUM  (  t  ) 
((t) (! TYPE_SIGNED (t) \ ? (t) 1 \ : ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT  1))))
#define TYPE_MINIMUM  (  t  ) 
((t) (! TYPE_SIGNED (t) \ ? (t) 0 \ : TYPE_SIGNED_MAGNITUDE (t) \ ? ~ (t) 0 \ : ~ (t) 0 << (sizeof (t) * CHAR_BIT  1)))
#define TYPE_ONES_COMPLEMENT  (  t  )  ((t) ~ (t) 0 == 0) 
#define TYPE_SIGNED  (  t  )  (! ((t) 0 < (t) 1)) 
#define TYPE_SIGNED_MAGNITUDE  (  t  )  ((t) ~ (t) 0 < (t) 1) 
#define TYPE_TWOS_COMPLEMENT  (  t  )  ((t) ~ (t) 0 == (t) 1) 
#define verify  (  name,  
assertion  
)  struct name { char a[(assertion) ? 1 : 1]; } 
time_t __mktime_internal  (  struct tm *  tp, 
struct tm *(*)(const time_t *, struct tm *)  convert,  
time_t *  offset  
) 
Definition at line 276 of file mktime.c.
{ time_t t, gt, t0, t1, t2; struct tm tm; /* The maximum number of probes (calls to CONVERT) should be enough to handle any combinations of time zone rule changes, solar time, leap seconds, and oscillations around a springforward gap. POSIX.1 prohibits leap seconds, but some hosts have them anyway. */ int remaining_probes = 6; /* Time requested. Copy it in case CONVERT modifies *TP; this can occur if TP is localtime's returned value and CONVERT is localtime. */ int sec = tp>tm_sec; int min = tp>tm_min; int hour = tp>tm_hour; int mday = tp>tm_mday; int mon = tp>tm_mon; int year_requested = tp>tm_year; /* Normalize the value. */ int isdst = ((tp>tm_isdst >> (8 * sizeof (tp>tm_isdst)  1))  (tp>tm_isdst != 0)); /* 1 if the previous probe was DST. */ int dst2; /* Ensure that mon is in range, and set year accordingly. */ int mon_remainder = mon % 12; int negative_mon_remainder = mon_remainder < 0; int mon_years = mon / 12  negative_mon_remainder; long int lyear_requested = year_requested; long int year = lyear_requested + mon_years; /* The other values need not be in range: the remaining code handles minor overflows correctly, assuming int and time_t arithmetic wraps around. Major overflows are caught at the end. */ /* Calculate day of year from year, month, and day of month. The result need not be in range. */ int mon_yday = ((__mon_yday[leapyear (year)] [mon_remainder + 12 * negative_mon_remainder])  1); long int lmday = mday; long int yday = mon_yday + lmday; time_t guessed_offset = *offset; int sec_requested = sec; if (LEAP_SECONDS_POSSIBLE) { /* Handle outofrange seconds specially, since ydhms_tm_diff assumes every minute has 60 seconds. */ if (sec < 0) sec = 0; if (59 < sec) sec = 59; } /* Invert CONVERT by probing. First assume the same offset as last time. */ t0 = ydhms_diff (year, yday, hour, min, sec, EPOCH_YEAR  TM_YEAR_BASE, 0, 0, 0,  guessed_offset); if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3) { /* time_t isn't large enough to rule out overflows, so check for major overflows. A gross check suffices, since if t0 has overflowed, it is off by a multiple of TIME_T_MAX  TIME_T_MIN + 1. So ignore any component of the difference that is bounded by a small value. */ /* Approximate log base 2 of the number of time units per biennium. A biennium is 2 years; use this unit instead of years to avoid integer overflow. For example, 2 average Gregorian years are 2 * 365.2425 * 24 * 60 * 60 seconds, which is 63113904 seconds, and rint (log2 (63113904)) is 26. */ int ALOG2_SECONDS_PER_BIENNIUM = 26; int ALOG2_MINUTES_PER_BIENNIUM = 20; int ALOG2_HOURS_PER_BIENNIUM = 14; int ALOG2_DAYS_PER_BIENNIUM = 10; int LOG2_YEARS_PER_BIENNIUM = 1; int approx_requested_biennia = (SHR (year_requested, LOG2_YEARS_PER_BIENNIUM)  SHR (EPOCH_YEAR  TM_YEAR_BASE, LOG2_YEARS_PER_BIENNIUM) + SHR (mday, ALOG2_DAYS_PER_BIENNIUM) + SHR (hour, ALOG2_HOURS_PER_BIENNIUM) + SHR (min, ALOG2_MINUTES_PER_BIENNIUM) + (LEAP_SECONDS_POSSIBLE ? 0 : SHR (sec, ALOG2_SECONDS_PER_BIENNIUM))); int approx_biennia = SHR (t0, ALOG2_SECONDS_PER_BIENNIUM); int diff = approx_biennia  approx_requested_biennia; int abs_diff = diff < 0 ?  diff : diff; /* IRIX 4.0.5 cc miscaculates TIME_T_MIN / 3: it erroneously gives a positive value of 715827882. Setting a variable first then doing math on it seems to work. (ghazi@caip.rutgers.edu) */ time_t time_t_max = TIME_T_MAX; time_t time_t_min = TIME_T_MIN; time_t overflow_threshold = (time_t_max / 3  time_t_min / 3) >> ALOG2_SECONDS_PER_BIENNIUM; if (overflow_threshold < abs_diff) { /* Overflow occurred. Try repairing it; this might work if the time zone offset is enough to undo the overflow. */ time_t repaired_t0 = 1  t0; approx_biennia = SHR (repaired_t0, ALOG2_SECONDS_PER_BIENNIUM); diff = approx_biennia  approx_requested_biennia; abs_diff = diff < 0 ?  diff : diff; if (overflow_threshold < abs_diff) return 1; guessed_offset += repaired_t0  t0; t0 = repaired_t0; } } /* Repeatedly use the error to improve the guess. */ for (t = t1 = t2 = t0, dst2 = 0; (gt = guess_time_tm (year, yday, hour, min, sec, &t, ranged_convert (convert, &t, &tm)), t != gt); t1 = t2, t2 = t, t = gt, dst2 = tm.tm_isdst != 0) if (t == t1 && t != t2 && (tm.tm_isdst < 0  (isdst < 0 ? dst2 <= (tm.tm_isdst != 0) : (isdst != 0) != (tm.tm_isdst != 0)))) /* We can't possibly find a match, as we are oscillating between two values. The requested time probably falls within a springforward gap of size GT  T. Follow the common practice in this case, which is to return a time that is GT  T away from the requested time, preferring a time whose tm_isdst differs from the requested value. (If no tm_isdst was requested and only one of the two values has a nonzero tm_isdst, prefer that value.) In practice, this is more useful than returning 1. */ goto offset_found; else if (remaining_probes == 0) return 1; /* We have a match. Check whether tm.tm_isdst has the requested value, if any. */ if (isdst != tm.tm_isdst && 0 <= isdst && 0 <= tm.tm_isdst) { /* tm.tm_isdst has the wrong value. Look for a neighboring time with the right value, and use its UTC offset. Heuristic: probe the adjacent timestamps in both directions, looking for the desired isdst. This should work for all real time zone histories in the tz database. */ /* Distance between probes when looking for a DST boundary. In tzdata2003a, the shortest period of DST is 601200 seconds (e.g., America/Recife starting 20001008 01:00), and the shortest period of nonDST surrounded by DST is 694800 seconds (Africa/Tunis starting 19430417 01:00). Use the minimum of these two values, so we don't miss these short periods when probing. */ int stride = 601200; /* The longest period of DST in tzdata2003a is 536454000 seconds (e.g., America/Jujuy starting 19461001 01:00). The longest period of nonDST is much longer, but it makes no real sense to search for more than a year of nonDST, so use the DST max. */ int duration_max = 536454000; /* Search in both directions, so the maximum distance is half the duration; add the stride to avoid offby1 problems. */ int delta_bound = duration_max / 2 + stride; int delta, direction; for (delta = stride; delta < delta_bound; delta += stride) for (direction = 1; direction <= 1; direction += 2) { time_t ot = t + delta * direction; if ((ot < t) == (direction < 0)) { struct tm otm; ranged_convert (convert, &ot, &otm); if (otm.tm_isdst == isdst) { /* We found the desired tm_isdst. Extrapolate back to the desired time. */ t = guess_time_tm (year, yday, hour, min, sec, &ot, &otm); ranged_convert (convert, &t, &tm); goto offset_found; } } } } offset_found: *offset = guessed_offset + t  t0; if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec) { /* Adjust time to reflect the tm_sec requested, not the normalized value. Also, repair any damage from a false match due to a leap second. */ int sec_adjustment = (sec == 0 && tm.tm_sec == 60)  sec; t1 = t + sec_requested; t2 = t1 + sec_adjustment; if (((t1 < t) != (sec_requested < 0))  ((t2 < t1) != (sec_adjustment < 0))  ! convert (&t2, &tm)) return 1; t = t2; } *tp = tm; return t; }
static time_t guess_time_tm  (  long int  year, 
long int  yday,  
int  hour,  
int  min,  
int  sec,  
const time_t *  t,  
const struct tm *  tp  
)  [static] 
Definition at line 204 of file mktime.c.
{ if (tp) { time_t d = ydhms_diff (year, yday, hour, min, sec, tp>tm_year, tp>tm_yday, tp>tm_hour, tp>tm_min, tp>tm_sec); time_t t1 = *t + d; if ((t1 < *t) == (TYPE_SIGNED (time_t) ? d < 0 : TIME_T_MAX / 2 < d)) return t1; } /* Overflow occurred one way or another. Return the nearest result that is actually in range, except don't report a zero difference if the actual difference is nonzero, as that would cause a false match; and don't oscillate between two values, as that would confuse the springforward gap detector. */ return (*t < TIME_T_MIDPOINT ? (*t <= TIME_T_MIN + 1 ? *t + 1 : TIME_T_MIN) : (TIME_T_MAX  1 <= *t ? *t  1 : TIME_T_MAX)); }
static int leapyear  (  long int  year  )  [inline, static] 
Definition at line 119 of file mktime.c.
{ /* Don't add YEAR to TM_YEAR_BASE, as that might overflow. Also, work even if YEAR is negative. */ return ((year & 3) == 0 && (year % 100 != 0  ((year / 100) & 3) == ( (TM_YEAR_BASE / 100) & 3))); }
time_t mktime  (  struct tm *  tp  ) 
Definition at line 510 of file mktime.c.
{ #ifdef _LIBC /* POSIX.1 8.1.1 requires that whenever mktime() is called, the time zone names contained in the external variable `tzname' shall be set as if the tzset() function had been called. */ __tzset (); #endif return __mktime_internal (tp, __localtime_r, &localtime_offset); }
static struct tm* ranged_convert  (  struct tm *(*)(const time_t *, struct tm *)  convert, 
time_t *  t,  
struct tm *  tp  
)  [static, read] 
Definition at line 231 of file mktime.c.
{ struct tm *r = convert (t, tp); if (!r && *t) { time_t bad = *t; time_t ok = 0; /* BAD is a known unconvertible time_t, and OK is a known good one. Use binary search to narrow the range between BAD and OK until they differ by 1. */ while (bad != ok + (bad < 0 ? 1 : 1)) { time_t mid = *t = (bad < 0 ? bad + ((ok  bad) >> 1) : ok + ((bad  ok) >> 1)); r = convert (t, tp); if (r) ok = mid; else bad = mid; } if (!r && ok) { /* The last conversion attempt failed; revert to the most recent successful attempt. */ *t = ok; r = convert (t, tp); } } return r; }
verify  (  time_t_is_integer  , 
TYPE_IS_INTEGER(time_t)  
) 
verify  (  twos_complement_arithmetic  , 
TYPE_TWOS_COMPLEMENT(int)  
) 
verify  (  base_year_is_a_multiple_of_100  , 
TM_YEAR_BASE%  100 = =0 

) 
static time_t ydhms_diff  (  long int  year1, 
long int  yday1,  
int  hour1,  
int  min1,  
int  sec1,  
int  year0,  
int  yday0,  
int  hour0,  
int  min0,  
int  sec0  
)  [inline, static] 
Definition at line 165 of file mktime.c.
{ verify (C99_integer_division, 1 / 2 == 0); #if 0 /* This assertion fails on 32bit systems with 64bit time_t, such as NetBSD 5 on i386. */ verify (long_int_year_and_yday_are_wide_enough, INT_MAX <= LONG_MAX / 2  TIME_T_MAX <= UINT_MAX); #endif /* Compute intervening leap days correctly even if year is negative. Take care to avoid integer overflow here. */ int a4 = SHR (year1, 2) + SHR (TM_YEAR_BASE, 2)  ! (year1 & 3); int b4 = SHR (year0, 2) + SHR (TM_YEAR_BASE, 2)  ! (year0 & 3); int a100 = a4 / 25  (a4 % 25 < 0); int b100 = b4 / 25  (b4 % 25 < 0); int a400 = SHR (a100, 2); int b400 = SHR (b100, 2); int intervening_leap_days = (a4  b4)  (a100  b100) + (a400  b400); /* Compute the desired time in time_t precision. Overflow might occur here. */ time_t tyear1 = year1; time_t years = tyear1  year0; time_t days = 365 * years + yday1  yday0 + intervening_leap_days; time_t hours = 24 * days + hour1  hour0; time_t minutes = 60 * hours + min1  min0; time_t seconds = 60 * minutes + sec1  sec0; return seconds; }
const unsigned short int __mon_yday[2][13] [static] 
time_t localtime_offset [static] 