| long long __year_to_secs(long long year, int *is_leap) |
| { |
| if (year-2ULL <= 136) { |
| int y = year; |
| int leaps = (y-68)>>2; |
| if (!((y-68)&3)) { |
| leaps--; |
| if (is_leap) *is_leap = 1; |
| } else if (is_leap) *is_leap = 0; |
| return 31536000*(y-70) + 86400*leaps; |
| } |
| |
| int cycles, centuries, leaps, rem; |
| |
| if (!is_leap) is_leap = &(int){0}; |
| cycles = (year-100) / 400; |
| rem = (year-100) % 400; |
| if (rem < 0) { |
| cycles--; |
| rem += 400; |
| } |
| if (!rem) { |
| *is_leap = 1; |
| centuries = 0; |
| leaps = 0; |
| } else { |
| if (rem >= 200) { |
| if (rem >= 300) centuries = 3, rem -= 300; |
| else centuries = 2, rem -= 200; |
| } else { |
| if (rem >= 100) centuries = 1, rem -= 100; |
| else centuries = 0; |
| } |
| if (!rem) { |
| *is_leap = 0; |
| leaps = 0; |
| } else { |
| leaps = rem / 4U; |
| rem %= 4U; |
| *is_leap = !rem; |
| } |
| } |
| |
| leaps += 97*cycles + 24*centuries - *is_leap; |
| |
| return (year-100) * 31536000LL + leaps * 86400LL + 946684800 + 86400; |
| } |
