Now.hpp

   1 #ifndef NOW_DOT_HPP
   2 #define NOW_DOT_HPP
   3
   4 #include <cstring>
   5 #include <string_view>
   6 #include <sys/time.h>
   7
   8 #include <glog/logging.h>
   9
  10 class Now {
  11 public:
  12   Now();
  13
  14   auto        sec() const { return tv_.tv_sec; }
  15   auto        usec() const { return tv_.tv_usec; }
  16   const char* c_str() const { return c_str_; }
  17
  18   std::string_view as_string_view() const
  19   {
  20     return std::string_view{c_str(), strlen(c_str())};
  21   }
  22
  23 private:
  24   timeval tv_;
  25   char    c_str_[32]; // RFC 5322 date-time section 3.3.
  26
  27   friend std::ostream& operator<<(std::ostream& s, Now const& now)
  28   {
  29     return s << now.c_str_;
  30   }
  31 };
  32
  33 inline Now::Now()
  34 {
  35   PCHECK(gettimeofday(&tv_, nullptr) == 0);
  36   tm* ptm = CHECK_NOTNULL(localtime(&tv_.tv_sec));
  37   CHECK_EQ(strftime(c_str_, sizeof c_str_, "%a, %d %b %Y %H:%M:%S %z", ptm),
  38            sizeof(c_str_) - 1);
  39 }
  40
  41 #endif // NOW_DOT_HPP