MongoDB  2.7.0
timer-inl.h
1 // @file mongo/util/timer-inl.h
2 
3 /* Copyright 2010 10gen Inc.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
26 #pragma once
27 
28 #if defined(MONGO_HAVE_HEADER_UNISTD_H)
29 #include <unistd.h>
30 #endif
31 
32 #if defined(_WIN32)
33 
34 // On Windows, prefer the Windows-specific implementation, which employs QueryPerformanceCounter.
35 #include "mongo/util/timer-win32-inl.h"
36 
37 #elif defined(_POSIX_TIMERS) and _POSIX_TIMERS > 0 and defined(_POSIX_MONOTONIC_CLOCK) and _POSIX_MONOTONIC_CLOCK > 0
38 
39 // On systems that support the POSIX clock_gettime function, and the "monotonic" clock,
40 // use those.
41 #include "mongo/util/timer-posixclock-inl.h"
42 
43 #else
44 
45 // If all else fails, fall back to a generic implementation. Performance may suffer.
46 #include "mongo/util/timer-generic-inl.h"
47 
48 #endif