xref: /openbsd/gnu/lib/libiberty/src/getruntime.c (revision 150b7e42)
1 /* Return time used so far, in microseconds.
2    Copyright (C) 1994, 1999, 2002 Free Software Foundation, Inc.
3 
4 This file is part of the libiberty library.
5 Libiberty is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public
7 License as published by the Free Software Foundation; either
8 version 2 of the License, or (at your option) any later version.
9 
10 Libiberty is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 Library General Public License for more details.
14 
15 You should have received a copy of the GNU Library General Public
16 License along with libiberty; see the file COPYING.LIB.  If
17 not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
18 Boston, MA 02110-1301, USA.  */
19 
20 #include "config.h"
21 
22 #include "ansidecl.h"
23 #include "libiberty.h"
24 
25 /* On some systems (such as WindISS), you must include <sys/types.h>
26    to get the definition of "time_t" before you include <time.h>.  */
27 #include <sys/types.h>
28 
29 /* There are several ways to get elapsed execution time; unfortunately no
30    single way is available for all host systems, nor are there reliable
31    ways to find out which way is correct for a given host. */
32 
33 #ifdef TIME_WITH_SYS_TIME
34 # include <sys/time.h>
35 # include <time.h>
36 #else
37 # if HAVE_SYS_TIME_H
38 #  include <sys/time.h>
39 # else
40 #  ifdef HAVE_TIME_H
41 #   include <time.h>
42 #  endif
43 # endif
44 #endif
45 
46 #if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
47 #include <sys/resource.h>
48 #endif
49 
50 #ifdef HAVE_TIMES
51 #ifdef HAVE_SYS_PARAM_H
52 #include <sys/param.h>
53 #endif
54 #include <sys/times.h>
55 #endif
56 
57 #ifdef HAVE_UNISTD_H
58 #include <unistd.h>
59 #endif
60 
61 /* This is a fallback; if wrong, it will likely make obviously wrong
62    results. */
63 
64 #ifndef CLOCKS_PER_SEC
65 #define CLOCKS_PER_SEC 1
66 #endif
67 
68 #ifdef _SC_CLK_TCK
69 #define GNU_HZ  sysconf(_SC_CLK_TCK)
70 #else
71 #ifdef HZ
72 #define GNU_HZ  HZ
73 #else
74 #ifdef CLOCKS_PER_SEC
75 #define GNU_HZ  CLOCKS_PER_SEC
76 #endif
77 #endif
78 #endif
79 
80 /*
81 
82 @deftypefn Replacement long get_run_time (void)
83 
84 Returns the time used so far, in microseconds.  If possible, this is
85 the time used by this process, else it is the elapsed time since the
86 process started.
87 
88 @end deftypefn
89 
90 */
91 
92 long
get_run_time(void)93 get_run_time (void)
94 {
95 #if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
96   struct rusage rusage;
97 
98   getrusage (0, &rusage);
99   return (rusage.ru_utime.tv_sec * 1000000 + rusage.ru_utime.tv_usec
100 	  + rusage.ru_stime.tv_sec * 1000000 + rusage.ru_stime.tv_usec);
101 #else /* ! HAVE_GETRUSAGE */
102 #ifdef HAVE_TIMES
103   struct tms tms;
104 
105   times (&tms);
106   return (tms.tms_utime + tms.tms_stime) * (1000000 / GNU_HZ);
107 #else /* ! HAVE_TIMES */
108   /* Fall back on clock and hope it's correctly implemented. */
109   const long clocks_per_sec = CLOCKS_PER_SEC;
110   if (clocks_per_sec <= 1000000)
111     return clock () * (1000000 / clocks_per_sec);
112   else
113     return clock () / clocks_per_sec;
114 #endif  /* HAVE_TIMES */
115 #endif  /* HAVE_GETRUSAGE */
116 }
117