1 /* Copyright (c) 2004, 2017, Oracle and/or its affiliates. All rights reserved.
2
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License, version 2.0,
5 as published by the Free Software Foundation.
6
7 This program is also distributed with certain software (including
8 but not limited to OpenSSL) that is licensed under separate terms,
9 as designated in a particular file or component or in included license
10 documentation. The authors of MySQL hereby grant you an additional
11 permission to link the program and your derivative works with the
12 separately licensed software that they have included with MySQL.
13
14 Without limiting anything contained in the foregoing, this file,
15 which is part of C Driver for MySQL (Connector/C), is also subject to the
16 Universal FOSS Exception, version 1.0, a copy of which can be found at
17 http://oss.oracle.com/licenses/universal-foss-exception.
18
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License, version 2.0, for more details.
23
24 You should have received a copy of the GNU General Public License
25 along with this program; if not, write to the Free Software
26 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */
27
28 /* get time since epoc in 100 nanosec units */
29 /* thus to get the current time we should use the system function
30 with the highest possible resolution */
31
32 /*
33 TODO: in functions my_micro_time() and my_micro_time_and_time() there
34 exists some common code that should be merged into a function.
35 */
36
37 #include "mysys_priv.h"
38 #include "my_static.h"
39
40 #if defined(_WIN32)
41 #include "my_sys.h" /* for my_printf_error */
42 typedef VOID(WINAPI *time_fn)(LPFILETIME);
43 static time_fn my_get_system_time_as_file_time= GetSystemTimeAsFileTime;
44
45 /**
46 Initialise highest available time resolution API on Windows
47 @return Initialization result
48 @retval FALSE Success
49 @retval TRUE Error. Couldn't initialize environment
50 */
win_init_get_system_time_as_file_time()51 my_bool win_init_get_system_time_as_file_time()
52 {
53 DWORD error;
54 HMODULE h;
55 h= LoadLibrary("kernel32.dll");
56 if (h != NULL)
57 {
58 time_fn pfn= (time_fn) GetProcAddress(h, "GetSystemTimePreciseAsFileTime");
59 if (pfn)
60 my_get_system_time_as_file_time= pfn;
61
62 return FALSE;
63 }
64
65 error= GetLastError();
66 my_printf_error(0,
67 "LoadLibrary(\"kernel32.dll\") failed: GetLastError returns %lu",
68 MYF(0),
69 error);
70
71 return TRUE;
72 }
73 #endif
74
75
76 /**
77 Get high-resolution time.
78
79 @remark For windows platforms we need the frequency value of
80 the CPU. This is initialized in my_init.c through
81 QueryPerformanceFrequency(). If the Windows platform
82 doesn't support QueryPerformanceFrequency(), zero is
83 returned.
84
85 @retval current high-resolution time.
86 */
87
my_getsystime()88 ulonglong my_getsystime()
89 {
90 #ifdef HAVE_CLOCK_GETTIME
91 struct timespec tp;
92 clock_gettime(CLOCK_REALTIME, &tp);
93 return (ulonglong)tp.tv_sec*10000000+(ulonglong)tp.tv_nsec/100;
94 #elif defined(_WIN32)
95 LARGE_INTEGER t_cnt;
96 if (query_performance_frequency)
97 {
98 QueryPerformanceCounter(&t_cnt);
99 return ((t_cnt.QuadPart / query_performance_frequency * 10000000) +
100 ((t_cnt.QuadPart % query_performance_frequency) * 10000000 /
101 query_performance_frequency) + query_performance_offset);
102 }
103 return 0;
104 #else
105 /* TODO: check for other possibilities for hi-res timestamping */
106 struct timeval tv;
107 gettimeofday(&tv,NULL);
108 return (ulonglong)tv.tv_sec*10000000+(ulonglong)tv.tv_usec*10;
109 #endif
110 }
111
112
113 /**
114 Return current time.
115
116 @param flags If MY_WME is set, write error if time call fails.
117
118 @retval current time.
119 */
120
my_time(myf flags)121 time_t my_time(myf flags)
122 {
123 time_t t;
124 /* The following loop is here beacuse time() may fail on some systems */
125 while ((t= time(0)) == (time_t) -1)
126 {
127 if (flags & MY_WME)
128 fprintf(stderr, "%s: Warning: time() call failed\n", my_progname);
129 }
130 return t;
131 }
132
133
134 #define OFFSET_TO_EPOCH 116444736000000000ULL
135
136 /**
137 Return time in microseconds.
138
139 @remark This function is to be used to measure performance in
140 micro seconds.
141
142 @retval Number of microseconds since the Epoch, 1970-01-01 00:00:00 +0000 (UTC)
143 */
144
my_micro_time()145 ulonglong my_micro_time()
146 {
147 #ifdef _WIN32
148 ulonglong newtime;
149 my_get_system_time_as_file_time((FILETIME*)&newtime);
150 newtime-= OFFSET_TO_EPOCH;
151 return (newtime/10);
152 #else
153 ulonglong newtime;
154 struct timeval t;
155 /*
156 The following loop is here because gettimeofday may fail on some systems
157 */
158 while (gettimeofday(&t, NULL) != 0)
159 {}
160 newtime= (ulonglong)t.tv_sec * 1000000 + t.tv_usec;
161 return newtime;
162 #endif
163 }
164
165
166 /**
167 Return time in seconds and timer in microseconds (not different start!)
168
169 @param time_arg Will be set to seconds since epoch.
170
171 @remark This function is to be useful when we need both the time and
172 microtime. For example in MySQL this is used to get the query
173 time start of a query and to measure the time of a query (for
174 the slow query log)
175
176 @remark The time source is the same as for my_micro_time(), meaning
177 that time values returned by both functions can be intermixed
178 in meaningful ways (i.e. for comparison purposes).
179
180 @retval Value in microseconds from some undefined point in time.
181 */
182
183 /* Difference between GetSystemTimeAsFileTime() and now() */
184
my_micro_time_and_time(time_t * time_arg)185 ulonglong my_micro_time_and_time(time_t *time_arg)
186 {
187 #ifdef _WIN32
188 ulonglong newtime;
189 GetSystemTimeAsFileTime((FILETIME*)&newtime);
190 *time_arg= (time_t) ((newtime - OFFSET_TO_EPOCH) / 10000000);
191 return (newtime/10);
192 #else
193 ulonglong newtime;
194 struct timeval t;
195 /*
196 The following loop is here because gettimeofday may fail on some systems
197 */
198 while (gettimeofday(&t, NULL) != 0)
199 {}
200 *time_arg= t.tv_sec;
201 newtime= (ulonglong)t.tv_sec * 1000000 + t.tv_usec;
202 return newtime;
203 #endif
204 }
205
206
207 /**
208 Returns current time.
209
210 @param microtime Value from very recent my_micro_time().
211
212 @remark This function returns the current time. The microtime argument
213 is only used if my_micro_time() uses a function that can safely
214 be converted to the current time.
215
216 @retval current time.
217 */
218
my_time_possible_from_micro(ulonglong microtime MY_ATTRIBUTE ((unused)))219 time_t my_time_possible_from_micro(ulonglong microtime MY_ATTRIBUTE((unused)))
220 {
221 #ifdef _WIN32
222 time_t t;
223 while ((t= time(0)) == (time_t) -1)
224 {}
225 return t;
226 #else
227 return (time_t) (microtime / 1000000);
228 #endif
229 }
230
231