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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 17:39:29 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 17:39:29 +0000 |
commit | 8ffec2a3aba6f114784e11f89ef1d57a096ae540 (patch) | |
tree | ccebcbad06203e8241a8e7249f8e6c478a3682ea /lib/gettimeofday.c | |
parent | Initial commit. (diff) | |
download | coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.tar.xz coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.zip |
Adding upstream version 8.32.upstream/8.32upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/gettimeofday.c')
-rw-r--r-- | lib/gettimeofday.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/lib/gettimeofday.c b/lib/gettimeofday.c new file mode 100644 index 0000000..b63f8f2 --- /dev/null +++ b/lib/gettimeofday.c @@ -0,0 +1,150 @@ +/* Provide gettimeofday for systems that don't have it or for which it's broken. + + Copyright (C) 2001-2003, 2005-2007, 2009-2020 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, see <https://www.gnu.org/licenses/>. */ + +/* written by Jim Meyering */ + +#include <config.h> + +/* Specification. */ +#include <sys/time.h> + +#include <time.h> + +#if defined _WIN32 && ! defined __CYGWIN__ +# define WINDOWS_NATIVE +# include <windows.h> +#endif + +#include "localtime-buffer.h" + +#ifdef WINDOWS_NATIVE + +/* Avoid warnings from gcc -Wcast-function-type. */ +# define GetProcAddress \ + (void *) GetProcAddress + +/* GetSystemTimePreciseAsFileTime was introduced only in Windows 8. */ +typedef void (WINAPI * GetSystemTimePreciseAsFileTimeFuncType) (FILETIME *lpTime); +static GetSystemTimePreciseAsFileTimeFuncType GetSystemTimePreciseAsFileTimeFunc = NULL; +static BOOL initialized = FALSE; + +static void +initialize (void) +{ + HMODULE kernel32 = LoadLibrary ("kernel32.dll"); + if (kernel32 != NULL) + { + GetSystemTimePreciseAsFileTimeFunc = + (GetSystemTimePreciseAsFileTimeFuncType) GetProcAddress (kernel32, "GetSystemTimePreciseAsFileTime"); + } + initialized = TRUE; +} + +#endif + +/* This is a wrapper for gettimeofday. It is used only on systems + that lack this function, or whose implementation of this function + causes problems. + Work around the bug in some systems whereby gettimeofday clobbers + the static buffer that localtime uses for its return value. The + gettimeofday function from Mac OS X 10.0.4 (i.e., Darwin 1.3.7) has + this problem. */ + +int +gettimeofday (struct timeval *restrict tv, void *restrict tz) +{ +#undef gettimeofday +#ifdef WINDOWS_NATIVE + + /* On native Windows, there are two ways to get the current time: + GetSystemTimeAsFileTime + <https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimeasfiletime> + or + GetSystemTimePreciseAsFileTime + <https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime>. + GetSystemTimeAsFileTime produces values that jump by increments of + 15.627 milliseconds (!) on average. + Whereas GetSystemTimePreciseAsFileTime values usually jump by 1 or 2 + microseconds. + More discussion on this topic: + <http://www.windowstimestamp.com/description>. */ + FILETIME current_time; + + if (!initialized) + initialize (); + if (GetSystemTimePreciseAsFileTimeFunc != NULL) + GetSystemTimePreciseAsFileTimeFunc (¤t_time); + else + GetSystemTimeAsFileTime (¤t_time); + + /* Convert from FILETIME to 'struct timeval'. */ + /* FILETIME: <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-filetime> */ + ULONGLONG since_1601 = + ((ULONGLONG) current_time.dwHighDateTime << 32) + | (ULONGLONG) current_time.dwLowDateTime; + /* Between 1601-01-01 and 1970-01-01 there were 280 normal years and 89 leap + years, in total 134774 days. */ + ULONGLONG since_1970 = + since_1601 - (ULONGLONG) 134774 * (ULONGLONG) 86400 * (ULONGLONG) 10000000; + ULONGLONG microseconds_since_1970 = since_1970 / (ULONGLONG) 10; + tv->tv_sec = microseconds_since_1970 / (ULONGLONG) 1000000; + tv->tv_usec = microseconds_since_1970 % (ULONGLONG) 1000000; + + return 0; + +#else + +# if HAVE_GETTIMEOFDAY +# if GETTIMEOFDAY_CLOBBERS_LOCALTIME + /* Save and restore the contents of the buffer used for localtime's + result around the call to gettimeofday. */ + struct tm save = *localtime_buffer_addr; +# endif + +# if defined timeval /* 'struct timeval' overridden by gnulib? */ +# undef timeval + struct timeval otv; + int result = gettimeofday (&otv, (struct timezone *) tz); + if (result == 0) + { + tv->tv_sec = otv.tv_sec; + tv->tv_usec = otv.tv_usec; + } +# else + int result = gettimeofday (tv, (struct timezone *) tz); +# endif + +# if GETTIMEOFDAY_CLOBBERS_LOCALTIME + *localtime_buffer_addr = save; +# endif + + return result; + +# else + +# if !defined OK_TO_USE_1S_CLOCK +# error "Only 1-second nominal clock resolution found. Is that intended?" \ + "If so, compile with the -DOK_TO_USE_1S_CLOCK option." +# endif + tv->tv_sec = time (NULL); + tv->tv_usec = 0; + + return 0; + +# endif +#endif +} |