From b022e54bd100a914417e216d0872d3e67edecaf9 Mon Sep 17 00:00:00 2001 From: Anatol Belski Date: Sat, 23 Mar 2013 17:40:06 +0100 Subject: Fixed possible precision loss in microtime This is related to the fix for bug #64370. MSVC natively supports __int64 type, so calculating with 32 bit ints is neither necessary nor reliable. Therefore an older piece of code is reused. --- win32/time.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) (limited to 'win32/time.c') diff --git a/win32/time.c b/win32/time.c index 77e4504cd1..75539748e8 100644 --- a/win32/time.c +++ b/win32/time.c @@ -50,6 +50,7 @@ int getfilesystemtime(struct timeval *tv) FILETIME ft; unsigned __int64 ff = 0; MyGetSystemTimeAsFileTime timefunc; + ULARGE_INTEGER fft; timefunc = get_time_func(); if (timefunc) { @@ -58,14 +59,20 @@ int getfilesystemtime(struct timeval *tv) GetSystemTimeAsFileTime(&ft); } - ff |= ft.dwHighDateTime; - ff <<= 32; - ff |= ft.dwLowDateTime; - ff /= 10; /* convert to microseconds */ + /* + * Do not cast a pointer to a FILETIME structure to either a + * ULARGE_INTEGER* or __int64* value because it can cause alignment faults on 64-bit Windows. + * via http://technet.microsoft.com/en-us/library/ms724284(v=vs.85).aspx + */ + fft.HighPart = ft.dwHighDateTime; + fft.LowPart = ft.dwLowDateTime; + ff = fft.QuadPart; + + ff /= 10Ui64; /* convert to microseconds */ ff -= 11644473600000000Ui64; /* convert to unix epoch */ - tv->tv_sec = (long)(ff / 1000000UL); - tv->tv_usec = (long)(ff % 1000000UL); + tv->tv_sec = (long)(ff / 1000000Ui64); + tv->tv_usec = (long)(ff % 1000000Ui64); return 0; } -- cgit v1.2.1