src/hotspot/share/runtime/os.cpp

*** 87,105 ****
  static size_t cur_malloc_words = 0;  // current size for MallocMaxTestWords
  
  DEBUG_ONLY(bool os::_mutex_init_done = false;)
  
  static time_t get_timezone(const struct tm* time_struct) {
  #if defined(_ALLBSD_SOURCE)
!   return time_struct->tm_gmtoff;
  #elif defined(_WINDOWS)
    long zone;
    _get_timezone(&zone);
!   return static_cast<time_t>(zone);
  #else
!   return timezone;
  #endif
  }
  
  int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
    va_list args;
    va_start(args, fmt);
--- 87,122 ----
  static size_t cur_malloc_words = 0;  // current size for MallocMaxTestWords
  
  DEBUG_ONLY(bool os::_mutex_init_done = false;)
  
  static time_t get_timezone(const struct tm* time_struct) {
+   // seconds to add to local time to get UTC
+   time_t offset;
+ 
  #if defined(_ALLBSD_SOURCE)
!   offset = -(time_struct->tm_gmtoff);
  #elif defined(_WINDOWS)
    long zone;
    _get_timezone(&zone);
!   offset = static_cast<time_t>(zone);
  #else
!   offset = timezone;
! #endif
! 
! // tm_gmtoff already includes adjustment for daylight saving
! #if !defined(_ALLBSD_SOURCE)
!   // If daylight savings time is in effect,
!   // we are 1 hour East of our time zone
!   const time_t seconds_per_minute = 60;
!   const time_t minutes_per_hour = 60;
!   const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
!   if (time_struct->tm_isdst > 0) {
!     offset = offset - seconds_per_hour;
!   }
  #endif
+ 
+   return offset;
  }
  
  int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
    va_list args;
    va_start(args, fmt);
*** 150,170 ****
      if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
        assert(false, "Failed localtime_pd");
        return NULL;
      }
    }
!   const time_t zone = get_timezone(&time_struct);
! 
!   // If daylight savings time is in effect,
!   // we are 1 hour East of our time zone
!   const time_t seconds_per_minute = 60;
!   const time_t minutes_per_hour = 60;
!   const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
!   time_t UTC_to_local = zone;
!   if (time_struct.tm_isdst > 0) {
!     UTC_to_local = UTC_to_local - seconds_per_hour;
!   }
  
    // No offset when dealing with UTC
    if (utc) {
      UTC_to_local = 0;
    }
--- 167,177 ----
      if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
        assert(false, "Failed localtime_pd");
        return NULL;
      }
    }
!   time_t UTC_to_local = get_timezone(&time_struct);
  
    // No offset when dealing with UTC
    if (utc) {
      UTC_to_local = 0;
    }
*** 181,190 ****
--- 188,200 ----
    if (local_to_UTC < 0) {
      sign_local_to_UTC = '-';
      abs_local_to_UTC = -(abs_local_to_UTC);
    }
    // Convert time zone offset seconds to hours and minutes.
+   const time_t seconds_per_minute = 60;
+   const time_t minutes_per_hour = 60;
+   const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
    const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
    const time_t zone_min =
      ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
  
    // Print an ISO 8601 date and time stamp into the buffer