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Victor Stinner
5c5022b862
Use a fraction internally in the _PyTime API to reduce the risk of integer overflow: simplify the fraction using Greatest Common Divisor (GCD). The fraction API is used by time functions: perf_counter(), monotonic() and process_time(). For example, QueryPerformanceFrequency() usually returns 10 MHz on Windows 10 and newer. The fraction SEC_TO_NS / frequency = 1_000_000_000 / 10_000_000 can be simplified to 100 / 1. * Add _PyTimeFraction type. * Add functions: * _PyTimeFraction_Set() * _PyTimeFraction_Mul() * _PyTimeFraction_Resolution() * No longer check "numer * denom <= _PyTime_MAX" in _PyTimeFraction_Set(). _PyTimeFraction_Mul() uses _PyTime_Mul() which handles integer overflow.
The Python C API ================ The C API is divided into these sections: 1. ``Include/``: Limited API 2. ``Include/cpython/``: CPython implementation details 3. ``Include/cpython/``, names with the ``PyUnstable_`` prefix: API that can change between minor releases 4. ``Include/internal/``, and any name with ``_`` prefix: The internal API Information on changing the C API is available `in the developer guide`_ .. _in the developer guide: https://devguide.python.org/c-api/