1 /*
2  * Copyright (c) 2005, Herv� Drolon, FreeImage Team
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
15  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
18  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #ifdef _WIN32
28 #include <windows.h>
29 #else
30 #include <sys/time.h>
31 #include <sys/resource.h>
32 #include <sys/times.h>
33 #endif /* _WIN32 */
34 #include "opj_includes.h"
35 
opj_clock(void)36 double opj_clock(void) {
37 #ifdef _WIN32
38 	/* _WIN32: use QueryPerformance (very accurate) */
39     LARGE_INTEGER freq , t ;
40     /* freq is the clock speed of the CPU */
41     QueryPerformanceFrequency(&freq) ;
42 	/* cout << "freq = " << ((double) freq.QuadPart) << endl; */
43     /* t is the high resolution performance counter (see MSDN) */
44     QueryPerformanceCounter ( & t ) ;
45     return ( t.QuadPart /(double) freq.QuadPart ) ;
46 #else
47 #if 0 /* EMSCRIPTEN: ifdef this out, and add code to use gettimeofday instead of getrusage */
48 	/* Unix or Linux: use resource usage */
49     struct rusage t;
50     double procTime;
51     /* (1) Get the rusage data structure at this moment (man getrusage) */
52     getrusage(0,&t);
53     /* (2) What is the elapsed time ? - CPU time = User time + System time */
54 	/* (2a) Get the seconds */
55     procTime = t.ru_utime.tv_sec + t.ru_stime.tv_sec;
56     /* (2b) More precisely! Get the microseconds part ! */
57     return ( procTime + (t.ru_utime.tv_usec + t.ru_stime.tv_usec) * 1e-6 ) ;
58 #else
59     struct timeval tv;
60     static double last = -1;
61     double curr, ret;
62     gettimeofday(&tv, NULL);
63     curr = tv.tv_sec + tv.tv_usec/(1000.0f*1000.0f);
64     if (last < 0) last = curr;
65     ret = curr - last;
66     last = curr;
67     return ret;
68 #endif
69 #endif
70 }
71 
72