1/*
2 * QEMU System Emulator
3 *
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24#include "qemu/osdep.h"
25#include "qemu/timer.h"
26
27/***********************************************************/
28/* real time host monotonic timer */
29
30#ifdef _WIN32
31
32int64_t clock_freq;
33
34static void __attribute__((constructor)) init_get_clock(void)
35{
36 LARGE_INTEGER freq;
37 int ret;
38 ret = QueryPerformanceFrequency(&freq);
39 if (ret == 0) {
40 fprintf(stderr, "Could not calibrate ticks\n");
41 exit(1);
42 }
43 clock_freq = freq.QuadPart;
44}
45
46#else
47
48int use_rt_clock;
49
50static void __attribute__((constructor)) init_get_clock(void)
51{
52 use_rt_clock = 0;
53#ifdef CLOCK_MONOTONIC
54 {
55 struct timespec ts;
56 if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) {
57 use_rt_clock = 1;
58 }
59 }
60#endif
61}
62#endif
63