diff options
Diffstat (limited to 'time64.c')
| -rw-r--r-- | time64.c | 143 |
1 files changed, 107 insertions, 36 deletions
@@ -54,11 +54,12 @@ static const int julian_days_by_month[2][12] = { static const int length_of_year[2] = { 365, 366 }; /* Number of days in a 400 year Gregorian cycle */ -static const int years_in_gregorian_cycle = 400; +static const Year years_in_gregorian_cycle = 400; static const int days_in_gregorian_cycle = (365 * 400) + 100 - 4 + 1; /* 28 year calendar cycle between 2010 and 2037 */ -static const int safe_years[28] = { +#define SOLAR_CYCLE_LENGTH 28 +static const int safe_years[SOLAR_CYCLE_LENGTH] = { 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026, 2027, @@ -68,7 +69,6 @@ static const int safe_years[28] = { 2012, 2013, 2014, 2015 }; -#define SOLAR_CYCLE_LENGTH 28 static const int dow_year_start[SOLAR_CYCLE_LENGTH] = { 5, 0, 1, 2, /* 0 2016 - 2019 */ 3, 5, 6, 0, /* 4 */ @@ -102,7 +102,7 @@ static const int dow_year_start[SOLAR_CYCLE_LENGTH] = { ) -int _is_exception_century(Int64 year) +static int is_exception_century(Int64 year) { int is_exception = ((year % 100 == 0) && !(year % 400 == 0)); /* printf("is_exception_century: %s\n", is_exception ? "yes" : "no"); */ @@ -111,14 +111,7 @@ int _is_exception_century(Int64 year) } -/* timegm() is a GNU extension, so emulate it here if we need it */ -#ifdef HAS_TIMEGM -# define TIMEGM(n) timegm(n); -#else -# define TIMEGM(n) ((time_t)timegm64(n)); -#endif - -Time64_T timegm64(struct tm *date) { +Time64_T timegm64(struct TM *date) { int days = 0; Int64 seconds = 0; Int64 year; @@ -153,7 +146,7 @@ Time64_T timegm64(struct tm *date) { } -int _check_tm(struct tm *tm) +static int check_tm(struct TM *tm) { /* Don't forget leap seconds */ assert(tm->tm_sec >= 0); @@ -189,7 +182,7 @@ int _check_tm(struct tm *tm) /* The exceptional centuries without leap years cause the cycle to shift by 16 */ -Year _cycle_offset(Year year) +static Year cycle_offset(Year year) { const Year start_year = 2000; Year year_diff = year - start_year; @@ -226,17 +219,17 @@ Year _cycle_offset(Year year) It doesn't need the same leap year status since we only care about January 1st. */ -int _safe_year(Year year) +static int safe_year(Year year) { int safe_year; - Year year_cycle = year + _cycle_offset(year); + Year year_cycle = year + cycle_offset(year); /* Change non-leap xx00 years to an equivalent */ - if( _is_exception_century(year) ) + if( is_exception_century(year) ) year_cycle += 11; /* Also xx01 years, since the previous year will be wrong */ - if( _is_exception_century(year - 1) ) + if( is_exception_century(year - 1) ) year_cycle += 17; year_cycle %= SOLAR_CYCLE_LENGTH; @@ -258,6 +251,70 @@ int _safe_year(Year year) } +void copy_tm_to_TM(const struct tm *src, struct TM *dest) { + if( src == NULL ) { + memset(dest, 0, sizeof(*dest)); + } + else { +# ifdef USE_TM64 + dest->tm_sec = src->tm_sec; + dest->tm_min = src->tm_min; + dest->tm_hour = src->tm_hour; + dest->tm_mday = src->tm_mday; + dest->tm_mon = src->tm_mon; + dest->tm_year = (Year)src->tm_year; + dest->tm_wday = src->tm_wday; + dest->tm_yday = src->tm_yday; + dest->tm_isdst = src->tm_isdst; + +# ifdef HAS_TM_TM_GMTOFF + dest->tm_gmtoff = src->tm_gmtoff; +# endif + +# ifdef HAS_TM_TM_ZONE + dest->tm_zone = src->tm_zone; +# endif + +# else + /* They're the same type */ + memcpy(dest, src, sizeof(*dest)); +# endif + } +} + + +void copy_TM_to_tm(const struct TM *src, struct tm *dest) { + if( src == NULL ) { + memset(dest, 0, sizeof(*dest)); + } + else { +# ifdef USE_TM64 + dest->tm_sec = src->tm_sec; + dest->tm_min = src->tm_min; + dest->tm_hour = src->tm_hour; + dest->tm_mday = src->tm_mday; + dest->tm_mon = src->tm_mon; + dest->tm_year = (int)src->tm_year; + dest->tm_wday = src->tm_wday; + dest->tm_yday = src->tm_yday; + dest->tm_isdst = src->tm_isdst; + +# ifdef HAS_TM_TM_GMTOFF + dest->tm_gmtoff = src->tm_gmtoff; +# endif + +# ifdef HAS_TM_TM_ZONE + dest->tm_zone = src->tm_zone; +# endif + +# else + /* They're the same type */ + memcpy(dest, src, sizeof(*dest)); +# endif + } +} + + /* Simulate localtime_r() to the best of our ability */ struct tm * fake_localtime_r(const time_t *clock, struct tm *result) { const struct tm *static_result = localtime(clock); @@ -292,7 +349,7 @@ struct tm * fake_gmtime_r(const time_t *clock, struct tm *result) { } -struct tm *gmtime64_r (const Time64_T *in_time, struct tm *p) +struct TM *gmtime64_r (const Time64_T *in_time, struct TM *p) { int v_tm_sec, v_tm_min, v_tm_hour, v_tm_mon, v_tm_wday; Int64 v_tm_tday; @@ -300,14 +357,19 @@ struct tm *gmtime64_r (const Time64_T *in_time, struct tm *p) Int64 m; Time64_T time = *in_time; Year year = 70; + int cycles = 0; assert(p != NULL); /* Use the system gmtime() if time_t is small enough */ if( SHOULD_USE_SYSTEM_GMTIME(*in_time) ) { time_t safe_time = *in_time; - GMTIME_R(&safe_time, p); - assert(_check_tm(p)); + struct tm safe_date; + GMTIME_R(&safe_time, &safe_date); + + copy_tm_to_TM(&safe_date, p); + assert(check_tm(p)); + return p; } @@ -344,9 +406,10 @@ struct tm *gmtime64_r (const Time64_T *in_time, struct tm *p) if (m >= 0) { /* Gregorian cycles, this is huge optimization for distant times */ - while (m >= (Time64_T) days_in_gregorian_cycle) { - m -= (Time64_T) days_in_gregorian_cycle; - year += years_in_gregorian_cycle; + cycles = floor(m / (Time64_T) days_in_gregorian_cycle); + if( cycles ) { + m -= (cycles * (Time64_T) days_in_gregorian_cycle); + year += (cycles * years_in_gregorian_cycle); } /* Years */ @@ -367,9 +430,10 @@ struct tm *gmtime64_r (const Time64_T *in_time, struct tm *p) year--; /* Gregorian cycles */ - while (m < (Time64_T) -days_in_gregorian_cycle) { - m += (Time64_T) days_in_gregorian_cycle; - year -= years_in_gregorian_cycle; + cycles = ceil(m / (Time64_T) days_in_gregorian_cycle) + 1; + if( cycles ) { + m -= (cycles * (Time64_T) days_in_gregorian_cycle); + year += (cycles * years_in_gregorian_cycle); } /* Years */ @@ -402,16 +466,17 @@ struct tm *gmtime64_r (const Time64_T *in_time, struct tm *p) p->tm_sec = v_tm_sec, p->tm_min = v_tm_min, p->tm_hour = v_tm_hour, p->tm_mon = v_tm_mon, p->tm_wday = v_tm_wday; - assert(_check_tm(p)); + assert(check_tm(p)); return p; } -struct tm *localtime64_r (const Time64_T *time, struct tm *local_tm) +struct TM *localtime64_r (const Time64_T *time, struct TM *local_tm) { time_t safe_time; - struct tm gm_tm; + struct tm safe_date; + struct TM gm_tm; Year orig_year; int month_diff; @@ -420,8 +485,12 @@ struct tm *localtime64_r (const Time64_T *time, struct tm *local_tm) /* Use the system localtime() if time_t is small enough */ if( SHOULD_USE_SYSTEM_LOCALTIME(*time) ) { safe_time = *time; - LOCALTIME_R(&safe_time, local_tm); - assert(_check_tm(local_tm)); + + LOCALTIME_R(&safe_time, &safe_date); + + copy_tm_to_TM(&safe_date, local_tm); + assert(check_tm(local_tm)); + return local_tm; } @@ -434,13 +503,15 @@ struct tm *localtime64_r (const Time64_T *time, struct tm *local_tm) gm_tm.tm_year < (1902 - 1900) ) { - gm_tm.tm_year = _safe_year(gm_tm.tm_year + 1900) - 1900; + gm_tm.tm_year = safe_year(gm_tm.tm_year + 1900) - 1900; } - safe_time = TIMEGM(&gm_tm); - if( LOCALTIME_R(&safe_time, local_tm) == NULL ) + safe_time = timegm64(&gm_tm); + if( LOCALTIME_R(&safe_time, &safe_date) == NULL ) return NULL; + copy_tm_to_TM(&safe_date, local_tm); + local_tm->tm_year = orig_year; if( local_tm->tm_year != orig_year ) { #ifdef EOVERFLOW @@ -475,7 +546,7 @@ struct tm *localtime64_r (const Time64_T *time, struct tm *local_tm) if( !IS_LEAP(local_tm->tm_year) && local_tm->tm_yday == 365 ) local_tm->tm_yday--; - assert(_check_tm(local_tm)); + assert(check_tm(local_tm)); return local_tm; } |