diff options
Diffstat (limited to 'time/tzset.c')
| -rw-r--r-- | time/tzset.c | 109 |
1 files changed, 89 insertions, 20 deletions
diff --git a/time/tzset.c b/time/tzset.c index 49935c04d3..6c16091ef5 100644 --- a/time/tzset.c +++ b/time/tzset.c @@ -17,6 +17,8 @@ Boston, MA 02111-1307, USA. */ #include <ctype.h> +#include <errno.h> +#include <bits/libc-lock.h> #include <stddef.h> #include <stdio.h> #include <stdlib.h> @@ -26,15 +28,19 @@ /* Defined in mktime.c. */ extern const unsigned short int __mon_yday[2][13]; +/* Defined in localtime.c. */ +extern struct tm _tmbuf; + #define NOID #include "tzfile.h" extern int __use_tzfile; extern void __tzfile_read __P ((const char *file)); +extern int __tzfile_compute __P ((time_t timer, int use_localtime, + long int *leap_correct, int *leap_hit)); extern void __tzfile_default __P ((const char *std, const char *dst, long int stdoff, long int dstoff)); extern char * __tzstring __P ((const char *string)); -extern int __tz_compute __P ((time_t timer, const struct tm *tm)); char *__tzname[2] = { (char *) "GMT", (char *) "GMT" }; int __daylight = 0; @@ -44,6 +50,9 @@ weak_alias (__tzname, tzname) weak_alias (__daylight, daylight) weak_alias (__timezone, timezone) +/* This locks all the state variables in tzfile.c and this file. */ +__libc_lock_define (static, tzset_lock) + #define min(a, b) ((a) < (b) ? (a) : (b)) #define max(a, b) ((a) > (b) ? (a) : (b)) @@ -74,6 +83,8 @@ static tz_rule tz_rules[2]; static int compute_change __P ((tz_rule *rule, int year)); +static int tz_compute __P ((time_t timer, const struct tm *tm)); +static void tzset_internal __P ((int always)); /* Header for a list of buffers containing time zone strings. */ struct tzstring_head @@ -139,9 +150,8 @@ __tzstring (string) static char *old_tz = NULL; /* Interpret the TZ envariable. */ -void __tzset_internal __P ((int always)); -void -__tzset_internal (always) +static void +tzset_internal (always) int always; { static int is_initialized = 0; @@ -426,7 +436,11 @@ size_t __tzname_cur_max; long int __tzname_max () { - __tzset_internal (0); + __libc_lock_lock (tzset_lock); + + tzset_internal (0); + + __libc_lock_unlock (tzset_lock); return __tzname_cur_max; } @@ -473,8 +487,9 @@ compute_change (rule, year) case M: /* Mm.n.d - Nth "Dth day" of month M. */ { - register int i, d, m1, yy0, yy1, yy2, dow; - register const unsigned short int *myday = + unsigned int i; + int d, m1, yy0, yy1, yy2, dow; + const unsigned short int *myday = &__mon_yday[__isleap (year)][rule->m]; /* First add SECSPERDAY for each day in months before M. */ @@ -496,7 +511,7 @@ compute_change (rule, year) d += 7; for (i = 1; i < rule->n; ++i) { - if (d + 7 >= myday[0] - myday[-1]) + if (d + 7 >= (int) myday[0] - myday[-1]) break; d += 7; } @@ -519,13 +534,11 @@ compute_change (rule, year) /* Figure out the correct timezone for *TIMER and TM (which must be the same) and set `__tzname', `__timezone', and `__daylight' accordingly. Return nonzero on success, zero on failure. */ -int -__tz_compute (timer, tm) +static int +tz_compute (timer, tm) time_t timer; const struct tm *tm; { - __tzset_internal (0); - if (! compute_change (&tz_rules[0], 1900 + tm->tm_year) || ! compute_change (&tz_rules[1], 1900 + tm->tm_year)) return 0; @@ -548,20 +561,15 @@ __tz_compute (timer, tm) return 1; } -#include <bits/libc-lock.h> - -/* This locks all the state variables in tzfile.c and this file. */ -__libc_lock_define (, __tzset_lock) - /* Reinterpret the TZ environment variable and set `tzname'. */ #undef tzset void __tzset (void) { - __libc_lock_lock (__tzset_lock); + __libc_lock_lock (tzset_lock); - __tzset_internal (1); + tzset_internal (1); if (!__use_tzfile) { @@ -570,6 +578,67 @@ __tzset (void) __tzname[1] = (char *) tz_rules[1].name; } - __libc_lock_unlock (__tzset_lock); + __libc_lock_unlock (tzset_lock); } weak_alias (__tzset, tzset) + +/* Return the `struct tm' representation of *TIMER in the local timezone. + Use local time if USE_LOCALTIME is nonzero, UTC otherwise. */ +struct tm * +__tz_convert (const time_t *timer, int use_localtime, struct tm *tp) +{ + long int leap_correction; + int leap_extra_secs; + + if (timer == NULL) + { + __set_errno (EINVAL); + return NULL; + } + + __libc_lock_lock (tzset_lock); + + /* Update internal database according to current TZ setting. + POSIX.1 8.3.7.2 says that localtime_r is not required to set tzname. + This is a good idea since this allows at least a bit more parallelism. + By analogy we apply the same rule to gmtime_r. */ + tzset_internal (tp == &_tmbuf); + + if (__use_tzfile) + { + if (! __tzfile_compute (*timer, use_localtime, + &leap_correction, &leap_extra_secs)) + tp = NULL; + } + else + { + __offtime (timer, 0, tp); + if (! tz_compute (*timer, tp)) + tp = NULL; + leap_correction = 0L; + leap_extra_secs = 0; + } + + if (tp) + { + if (use_localtime) + { + tp->tm_isdst = __daylight; + tp->tm_zone = __tzname[__daylight]; + tp->tm_gmtoff = __timezone; + } + else + { + tp->tm_isdst = 0; + tp->tm_zone = "GMT"; + tp->tm_gmtoff = 0L; + } + + __offtime (timer, tp->tm_gmtoff - leap_correction, tp); + tp->tm_sec += leap_extra_secs; + } + + __libc_lock_unlock (tzset_lock); + + return tp; +} |