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-rw-r--r--mysys/my_getsystime.c146
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diff --git a/mysys/my_getsystime.c b/mysys/my_getsystime.c
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+/* Copyright (c) 2004, 2011, Oracle and/or its affiliates.
+ Copyright (c) 2009-2011 Monty Program Ab
+
+ 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; version 2 of the License.
+
+ 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, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */
+
+
+#include "mysys_priv.h"
+#include "my_static.h"
+
+#ifdef _WIN32
+#define OFFSET_TO_EPOC 116444736000000000LL
+static ulonglong query_performance_frequency;
+#endif
+
+#ifdef HAVE_LINUX_UNISTD_H
+#include <linux/unistd.h>
+#endif
+
+/* For CYGWIN */
+#if !defined(CLOCK_THREAD_CPUTIME_ID) && defined(CLOCK_THREAD_CPUTIME)
+#define CLOCK_THREAD_CPUTIME_ID CLOCK_THREAD_CPUTIME
+#endif
+
+/*
+ return number of nanoseconds since unspecified (but always the same)
+ point in the past
+
+ NOTE:
+ Thus to get the current time we should use the system function
+ with the highest possible resolution
+
+ The value is not anchored to any specific point in time (e.g. epoch) nor
+ is it subject to resetting or drifting by way of adjtime() or settimeofday(),
+ and thus it is *NOT* appropriate for getting the current timestamp. It can be
+ used for calculating time intervals, though.
+*/
+
+ulonglong my_interval_timer()
+{
+#ifdef HAVE_CLOCK_GETTIME
+ struct timespec tp;
+ clock_gettime(CLOCK_MONOTONIC, &tp);
+ return tp.tv_sec*1000000000ULL+tp.tv_nsec;
+#elif defined(HAVE_GETHRTIME)
+ return gethrtime();
+#elif defined(_WIN32)
+ DBUG_ASSERT(query_performance_frequency);
+ LARGE_INTEGER t_cnt;
+ QueryPerformanceCounter(&t_cnt);
+ return (t_cnt.QuadPart / query_performance_frequency * 1000000000ULL) +
+ ((t_cnt.QuadPart % query_performance_frequency) * 1000000000ULL /
+ query_performance_frequency);
+#else
+ /* TODO: check for other possibilities for hi-res timestamping */
+ struct timeval tv;
+ gettimeofday(&tv,NULL);
+ return tv.tv_sec*1000000000ULL+tv.tv_usec*1000ULL;
+#endif
+}
+
+
+/* Return current time in HRTIME_RESOLUTION (microseconds) since epoch */
+
+my_hrtime_t my_hrtime()
+{
+ my_hrtime_t hrtime;
+#if defined(_WIN32)
+ ulonglong newtime;
+ GetSystemTimePreciseAsFileTime((FILETIME*)&newtime);
+ hrtime.val= (newtime - OFFSET_TO_EPOC)/10;
+#elif defined(HAVE_CLOCK_GETTIME)
+ struct timespec tp;
+ clock_gettime(CLOCK_REALTIME, &tp);
+ hrtime.val= tp.tv_sec*1000000ULL+tp.tv_nsec/1000ULL;
+#else
+ struct timeval t;
+ /* The following loop is here because gettimeofday may fail */
+ while (gettimeofday(&t, NULL) != 0) {}
+ hrtime.val= t.tv_sec*1000000ULL + t.tv_usec;
+#endif
+ DBUG_EXECUTE_IF("system_time_plus_one_hour", hrtime.val += 3600*1000000ULL;);
+ DBUG_EXECUTE_IF("system_time_minus_one_hour", hrtime.val -= 3600*1000000ULL;);
+ return hrtime;
+}
+
+#ifdef _WIN32
+
+/*
+ Low accuracy, "coarse" timer.
+ Has lower latency than my_hrtime(). Used in situations, where microsecond
+ precision is not needed, e.g in Windows pthread_cond_timedwait, where POSIX
+ interface needs nanoseconds, yet the underlying Windows function only
+ accepts millisecons.
+*/
+my_hrtime_t my_hrtime_coarse()
+{
+ my_hrtime_t hrtime;
+ ulonglong t;
+ GetSystemTimeAsFileTime((FILETIME*)&t);
+ hrtime.val= (t - OFFSET_TO_EPOC)/10;
+ return hrtime;
+}
+
+#endif
+
+void my_time_init()
+{
+#ifdef _WIN32
+ compile_time_assert(sizeof(LARGE_INTEGER) ==
+ sizeof(query_performance_frequency));
+ QueryPerformanceFrequency((LARGE_INTEGER *)&query_performance_frequency);
+ DBUG_ASSERT(query_performance_frequency);
+#endif
+}
+
+
+/*
+ Return cpu time in 1/10th on a microsecond (1e-7 s)
+*/
+
+ulonglong my_getcputime()
+{
+#ifdef CLOCK_THREAD_CPUTIME_ID
+ struct timespec tp;
+ if (clock_gettime(CLOCK_THREAD_CPUTIME_ID, &tp))
+ return 0;
+ return (ulonglong)tp.tv_sec*10000000+(ulonglong)tp.tv_nsec/100;
+#elif defined(__NR_clock_gettime)
+ struct timespec tp;
+ if (syscall(__NR_clock_gettime, CLOCK_THREAD_CPUTIME_ID, &tp))
+ return 0;
+ return (ulonglong)tp.tv_sec*10000000+(ulonglong)tp.tv_nsec/100;
+#endif /* CLOCK_THREAD_CPUTIME_ID */
+ return 0;
+}