tor-browser

TimeUtils.cpp (5954B)

---

// Windows/TimeUtils.cpp

#include "StdAfx.h"

#include "Defs.h"
#include "TimeUtils.h"

namespace NWindows {
namespace NTime {

static const UInt32 kNumTimeQuantumsInSecond = 10000000;
static const UInt32 kFileTimeStartYear = 1601;
static const UInt32 kDosTimeStartYear = 1980;
static const UInt32 kUnixTimeStartYear = 1970;
static const UInt64 kUnixTimeOffset =
   (UInt64)60 * 60 * 24 * (89 + 365 * (kUnixTimeStartYear - kFileTimeStartYear));
static const UInt64 kNumSecondsInFileTime = (UInt64)(Int64)-1 / kNumTimeQuantumsInSecond;

bool DosTimeToFileTime(UInt32 dosTime, FILETIME &ft) throw()
{
 #if defined(_WIN32) && !defined(UNDER_CE)
 return BOOLToBool(::DosDateTimeToFileTime((UInt16)(dosTime >> 16), (UInt16)(dosTime & 0xFFFF), &ft));
 #else
 ft.dwLowDateTime = 0;
 ft.dwHighDateTime = 0;
 UInt64 res;
 if (!GetSecondsSince1601(kDosTimeStartYear + (dosTime >> 25), (dosTime >> 21) & 0xF, (dosTime >> 16) & 0x1F,
     (dosTime >> 11) & 0x1F, (dosTime >> 5) & 0x3F, (dosTime & 0x1F) * 2, res))
   return false;
 res *= kNumTimeQuantumsInSecond;
 ft.dwLowDateTime = (UInt32)res;
 ft.dwHighDateTime = (UInt32)(res >> 32);
 return true;
 #endif
}

static const UInt32 kHighDosTime = 0xFF9FBF7D;
static const UInt32 kLowDosTime = 0x210000;

#define PERIOD_4 (4 * 365 + 1)
#define PERIOD_100 (PERIOD_4 * 25 - 1)
#define PERIOD_400 (PERIOD_100 * 4 + 1)

bool FileTimeToDosTime(const FILETIME &ft, UInt32 &dosTime) throw()
{
 #if defined(_WIN32) && !defined(UNDER_CE)

 WORD datePart, timePart;
 if (!::FileTimeToDosDateTime(&ft, &datePart, &timePart))
 {
   dosTime = (ft.dwHighDateTime >= 0x01C00000) ? kHighDosTime : kLowDosTime;
   return false;
 }
 dosTime = (((UInt32)datePart) << 16) + timePart;

 #else

 unsigned year, mon, day, hour, min, sec;
 UInt64 v64 = ft.dwLowDateTime | ((UInt64)ft.dwHighDateTime << 32);
 Byte ms[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
 unsigned temp;
 UInt32 v;
 v64 += (kNumTimeQuantumsInSecond * 2 - 1);
 v64 /= kNumTimeQuantumsInSecond;
 sec = (unsigned)(v64 % 60);
 v64 /= 60;
 min = (unsigned)(v64 % 60);
 v64 /= 60;
 hour = (unsigned)(v64 % 24);
 v64 /= 24;

 v = (UInt32)v64;

 year = (unsigned)(kFileTimeStartYear + v / PERIOD_400 * 400);
 v %= PERIOD_400;

 temp = (unsigned)(v / PERIOD_100);
 if (temp == 4)
   temp = 3;
 year += temp * 100;
 v -= temp * PERIOD_100;

 temp = v / PERIOD_4;
 if (temp == 25)
   temp = 24;
 year += temp * 4;
 v -= temp * PERIOD_4;

 temp = v / 365;
 if (temp == 4)
   temp = 3;
 year += temp;
 v -= temp * 365;

 if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))
   ms[1] = 29;
 for (mon = 1; mon <= 12; mon++)
 {
   unsigned s = ms[mon - 1];
   if (v < s)
     break;
   v -= s;
 }
 day = (unsigned)v + 1;

 dosTime = kLowDosTime;
 if (year < kDosTimeStartYear)
   return false;
 year -= kDosTimeStartYear;
 dosTime = kHighDosTime;
 if (year >= 128)
   return false;
 dosTime = (year << 25) | (mon << 21) | (day << 16) | (hour << 11) | (min << 5) | (sec >> 1);
 #endif
 return true;
}

UInt64 UnixTimeToFileTime64(UInt32 unixTime) throw()
{
 return (kUnixTimeOffset + (UInt64)unixTime) * kNumTimeQuantumsInSecond;
}

void UnixTimeToFileTime(UInt32 unixTime, FILETIME &ft) throw()
{
 UInt64 v = UnixTimeToFileTime64(unixTime);
 ft.dwLowDateTime = (DWORD)v;
 ft.dwHighDateTime = (DWORD)(v >> 32);
}

UInt64 UnixTime64ToFileTime64(Int64 unixTime) throw()
{
 return (UInt64)(kUnixTimeOffset + unixTime) * kNumTimeQuantumsInSecond;
}

bool UnixTime64ToFileTime(Int64 unixTime, FILETIME &ft) throw()
{
 if (unixTime > (Int64)(kNumSecondsInFileTime - kUnixTimeOffset))
 {
   ft.dwLowDateTime = ft.dwHighDateTime = (UInt32)(Int32)-1;
   return false;
 }
 Int64 v = (Int64)kUnixTimeOffset + unixTime;
 if (v < 0)
 {
   ft.dwLowDateTime = ft.dwHighDateTime = 0;
   return false;
 }
 UInt64 v2 = (UInt64)v * kNumTimeQuantumsInSecond;
 ft.dwLowDateTime = (DWORD)v2;
 ft.dwHighDateTime = (DWORD)(v2 >> 32);
 return true;
}

Int64 FileTimeToUnixTime64(const FILETIME &ft) throw()
{
 UInt64 winTime = (((UInt64)ft.dwHighDateTime) << 32) + ft.dwLowDateTime;
 return (Int64)(winTime / kNumTimeQuantumsInSecond) - (Int64)kUnixTimeOffset;
}

bool FileTimeToUnixTime(const FILETIME &ft, UInt32 &unixTime) throw()
{
 UInt64 winTime = (((UInt64)ft.dwHighDateTime) << 32) + ft.dwLowDateTime;
 winTime /= kNumTimeQuantumsInSecond;
 if (winTime < kUnixTimeOffset)
 {
   unixTime = 0;
   return false;
 }
 winTime -= kUnixTimeOffset;
 if (winTime > 0xFFFFFFFF)
 {
   unixTime = 0xFFFFFFFF;
   return false;
 }
 unixTime = (UInt32)winTime;
 return true;
}

bool GetSecondsSince1601(unsigned year, unsigned month, unsigned day,
 unsigned hour, unsigned min, unsigned sec, UInt64 &resSeconds) throw()
{
 resSeconds = 0;
 if (year < kFileTimeStartYear || year >= 10000 || month < 1 || month > 12 ||
     day < 1 || day > 31 || hour > 23 || min > 59 || sec > 59)
   return false;
 UInt32 numYears = year - kFileTimeStartYear;
 UInt32 numDays = numYears * 365 + numYears / 4 - numYears / 100 + numYears / 400;
 Byte ms[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
 if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))
   ms[1] = 29;
 month--;
 for (unsigned i = 0; i < month; i++)
   numDays += ms[i];
 numDays += day - 1;
 resSeconds = ((UInt64)(numDays * 24 + hour) * 60 + min) * 60 + sec;
 return true;
}

void GetCurUtcFileTime(FILETIME &ft) throw()
{
 // Both variants provide same low resolution on WinXP: about 15 ms.
 // But GetSystemTimeAsFileTime is much faster.

 #ifdef UNDER_CE
 SYSTEMTIME st;
 GetSystemTime(&st);
 SystemTimeToFileTime(&st, &ft);
 #else
 GetSystemTimeAsFileTime(&ft);
 #endif
}

}}