We already use _USE_32BIT_TIME_T in both SCons and Visual Studio builds.
/Søren

On Mon, Dec 1, 2008 at 3:19 PM, Mads Ager <[EMAIL PROTECTED]> wrote:

>
> Thanks Dean.  Bill put in explicit checks for that and we make sure to
> convert to a reasonable date in the caller.
>
> -- Mads
>
> On Mon, Dec 1, 2008 at 3:11 PM, Dean McNamee <[EMAIL PROTECTED]> wrote:
> > Just an fyi, beware of:
> >
> > http://securityvulns.com/advisories/year3000.asp
> >
> > -- dean
> >
> > On Mon, Dec 1, 2008 at 5:50 AM,  <[EMAIL PROTECTED]> wrote:
> >>
> >> Reviewers: Mike Belshe, Mads Ager,
> >>
> >> Message:
> >> Here is the change in the daylight saving time lookup
> >> code.  I also have a browser test for it, which I will email you.  I
> >> would like someone in the US to test it on a US Windows system, to check
> >> US DST calculations.
> >>
> >> It is much faster on Windows XP SP 3.
> >>
> >> Description:
> >> Change Windows daylight saving time calculations to
> >> use C stdlib local time functions, not Win32 functions.
> >> Win32 time functions slowed down with Windows XP SP3.
> >>
> >> Please review this at http://codereview.chromium.org/12824
> >>
> >> SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/
> >>
> >> Affected files:
> >>   M     src/platform-win32.cc
> >>
> >>
> >> Index: src/platform-win32.cc
> >> ===================================================================
> >> --- src/platform-win32.cc       (revision 875)
> >> +++ src/platform-win32.cc       (working copy)
> >> @@ -56,6 +56,7 @@
> >>
> >>  #include <windows.h>
> >>
> >> +#include <time.h>  // For LocalOffset() implementation.
> >>  #include <mmsystem.h>  // For timeGetTime().
> >>  #include <dbghelp.h>  // For SymLoadModule64 and al.
> >>  #include <tlhelp32.h>  // For Module32First and al.
> >> @@ -323,6 +324,8 @@
> >>    // Just return if timezone information has already been initialized.
> >>    if (tz_initialized_) return;
> >>
> >> +  // Initialize POSIX time zone data
> >> +  _tzset();
> >>    // Obtain timezone information from operating system.
> >>    memset(&tzinfo_, 0, sizeof(tzinfo_));
> >>    if (GetTimeZoneInformation(&tzinfo_) == TIME_ZONE_ID_INVALID) {
> >> @@ -396,9 +399,9 @@
> >>    static bool initialized = false;
> >>    static TimeStamp init_time;
> >>    static DWORD init_ticks;
> >> -  static const int kHundredNanosecondsPerSecond = 10000;
> >> -  static const int kMaxClockElapsedTime =
> >> -      60*60*24*kHundredNanosecondsPerSecond;  // 1 day
> >> +  static const int64_t kHundredNanosecondsPerSecond = 10000000;
> >> +  static const int64_t kMaxClockElapsedTime =
> >> +      60*kHundredNanosecondsPerSecond;  // 1 minute
> >>
> >>    // If we are uninitialized, we need to resync the clock.
> >>    bool needs_resync = !initialized;
> >> @@ -433,26 +436,31 @@
> >>    // Initialize timezone information, if needed.
> >>    TzSet();
> >>
> >> -  // Convert timestamp to date/time components. These are now in UTC
> >> -  // format. NB: Please do not replace the following three calls with
> one
> >> -  // call to FileTimeToLocalFileTime(), because it does not handle
> >> -  // daylight saving correctly.
> >> -  SYSTEMTIME utc;
> >> -  FileTimeToSystemTime(&ft(), &utc);
> >> +  Time rounded_to_second(*this);
> >> +  rounded_to_second.t() /= 1000 * kTimeScaler;
> >> +  rounded_to_second.t() *= 1000 * kTimeScaler;
> >> +  // Convert to local time using POSIX localtime function.
> >> +  // Windows XP Service Pack 3 made SystemTimeToTzSpecificLocalTime()
> >> +  // very slow.  Other browsers use localtime().
> >>
> >> -  // Convert to local time, using timezone information.
> >> -  SYSTEMTIME local;
> >> -  SystemTimeToTzSpecificLocalTime(&tzinfo_, &utc, &local);
> >> +  // Convert from JavaScript milliseconds past 1/1/1970 0:00:00 to
> >> +  // POSIX seconds past 1/1/1970 0:00:00.
> >> +  time_t posix_time = static_cast<time_t>(this->ToJSTime() / 1000);
> >> +  // Conversion to standard year by callers of this function should
> ensure
> >> +  // that the time is between the limits Jan 1, 1970 and Jan 1, 3001.
> >> +  // Exceeding these limits will terminate the program. This is
> >> +  // a Windows security feature.
> >> +  if (posix_time >= 32535244800i64) return 0;  // Jan 1, 3001.
> >> _MAX__TIME64_T
> >> +  // is reportedly the wrong limit, and is not declared in a standard
> >> header.
> >> +  if (posix_time < 0 ) return 0;
> >> +  // Convert to local time, as struct with fields for day, hour, year,
> etc.
> >> +  tm posix_local_time_struct;
> >> +  if (localtime_s(&posix_local_time_struct, &posix_time)) return 0;
> >> +  // Convert local time in struct to POSIX time as if it were a UTC
> time.
> >> +  time_t local_posix_time = _mkgmtime(&posix_local_time_struct);
> >> +  Time localtime(1000.0 * local_posix_time);
> >>
> >> -  // Convert local time back to a timestamp. This timestamp now
> >> -  // has a bias similar to the local timezone bias in effect
> >> -  // at the time of the original timestamp.
> >> -  Time localtime;
> >> -  SystemTimeToFileTime(&local, &localtime.ft());
> >> -
> >> -  // The difference between the new local timestamp and the original
> >> -  // timestamp and is the local timezone offset.
> >> -  return localtime.Diff(this);
> >> +  return localtime.Diff(&rounded_to_second);
> >>  }
> >>
> >>
> >>
> >>
> >>
> >> >>
> >>
> >
>
> >
>

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