localtime_r用cpu计算的方式代替

src/logging.cc

@@ -1418,7 +1418,8 @@ void LogMessage::Init(const char* file,
   data_->outvec_ = NULL;
   WallTime now = WallTime_Now();
   data_->timestamp_ = static_cast<time_t>(now);
-  localtime_r(&data_->timestamp_, &data_->tm_time_);
+//  localtime_r(&data_->timestamp_, &data_->tm_time_);
+  FastSecondToDate(data_->timestamp_, &data_->tm_time_, GetCurTimeZone());
   data_->usecs_ = static_cast<int32>((now - data_->timestamp_) * 1000000);
 
   data_->num_chars_to_log_ = 0;

src/utilities.cc

@@ -220,6 +220,54 @@ WallTime WallTime_Now() {
   return CycleClock_Now() * 0.000001;
 }
 
+int _GetCurTimeZone(){
+    int timezone = 0;
+    time_t t1, t2 ;
+    struct tm *tm_local, *tm_utc;
+
+    time(&t1);
+    t2 = t1;
+
+    tm_local = localtime(&t1);
+    t1 = mktime(tm_local) ;
+
+    tm_utc = gmtime(&t2);
+    t2 = mktime(tm_utc);
+
+    timezone = int((t1 - t2) / 3600);
+    return timezone;
+}
+static int32 g_timezone = _GetCurTimeZone();
+int32_t GetCurTimeZone(){
+    return g_timezone;
+}
+
+int FastSecondToDate(const time_t& unix_sec, struct tm* tm, int time_zone) {
+    static const int kHoursInDay = 24;
+    static const int kMinutesInHour = 60;
+    static const int kDaysFromUnixTime = 2472632;
+    static const int kDaysFromYear = 153;
+    static const int kMagicUnkonwnFirst = 146097;
+    static const int kMagicUnkonwnSec = 1461;
+    tm->tm_sec  =  unix_sec % kMinutesInHour;
+    int i      = (unix_sec/kMinutesInHour);
+    tm->tm_min  = i % kMinutesInHour; //nn
+    i /= kMinutesInHour;
+    tm->tm_hour = (i + time_zone) % kHoursInDay; // hh
+    tm->tm_mday = (i + time_zone) / kHoursInDay;
+    int a = tm->tm_mday + kDaysFromUnixTime;
+    int b = (a*4  + 3)/kMagicUnkonwnFirst;
+    int c = (-b*kMagicUnkonwnFirst)/4 + a;
+    int d =((c*4 + 3) / kMagicUnkonwnSec);
+    int e = -d * kMagicUnkonwnSec;
+    e = e/4 + c;
+    int m = (5*e + 2)/kDaysFromYear;
+    tm->tm_mday = -(kDaysFromYear * m + 2)/5 + e + 1;
+    tm->tm_mon = (-m/10)*12 + m + 2;
+    tm->tm_year = b*100 + d  - 6700 + (m/10);
+    return 0;
+}
+
 static int32 g_main_thread_pid = getpid();
 int32 GetMainThreadPid() {
   return g_main_thread_pid;

src/utilities.h

@@ -170,6 +170,9 @@ int64 UsecToCycles(int64 usec);
 typedef double WallTime;
 WallTime WallTime_Now();
 
+int32_t GetCurTimeZone();
+int32_t FastSecondToDate(const time_t& unix_sec, struct tm* tm, int time_zone);
+
 int32 GetMainThreadPid();
 bool PidHasChanged();