mpv/osdep/timer-win2.c

118 lines
3.2 KiB
C
Raw Normal View History

/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <windows.h>
#include <sys/time.h>
#include <mmsystem.h>
#include <stdlib.h>
#include <versionhelpers.h>
#include "timer.h"
#include "config.h"
static LARGE_INTEGER perf_freq;
// ms values
static int hires_max = 50;
static int hires_res = 1;
int mp_start_hires_timers(int wait_ms)
{
#if !HAVE_UWP
// policy: request hires_res ms resolution if wait < hires_max ms
if (wait_ms > 0 && wait_ms <= hires_max &&
timeBeginPeriod(hires_res) == TIMERR_NOERROR)
{
return hires_res;
}
#endif
return 0;
}
void mp_end_hires_timers(int res_ms)
{
#if !HAVE_UWP
if (res_ms > 0)
timeEndPeriod(res_ms);
#endif
}
void mp_sleep_us(int64_t us)
{
if (us < 0)
return;
// Sleep(0) won't sleep for one clocktick as the unix usleep
// instead it will only make the thread ready
// it may take some time until it actually starts to run again
if (us < 1000)
us = 1000;
int hrt = mp_start_hires_timers(us / 1000);
Sleep(us / 1000);
mp_end_hires_timers(hrt);
}
uint64_t mp_raw_time_us(void)
{
LARGE_INTEGER perf_count;
QueryPerformanceCounter(&perf_count);
// Convert QPC units (1/perf_freq seconds) to microseconds. This will work
// without overflow because the QPC value is guaranteed not to roll-over
// within 100 years, so perf_freq must be less than 2.9*10^9.
return perf_count.QuadPart / perf_freq.QuadPart * 1000000 +
perf_count.QuadPart % perf_freq.QuadPart * 1000000 / perf_freq.QuadPart;
}
void mp_raw_time_init(void)
{
QueryPerformanceFrequency(&perf_freq);
#if !HAVE_UWP
// allow (undocumented) control of all the High Res Timers parameters,
// for easier experimentation and diagnostic of bug reports.
const char *v;
// 1..1000 ms max timetout for hires (used in "perwait" mode)
if ((v = getenv("MPV_HRT_MAX"))) {
int hmax = atoi(v);
if (hmax >= 1 && hmax <= 1000)
hires_max = hmax;
}
// 1..15 ms hires resolution (not used in "never" mode)
if ((v = getenv("MPV_HRT_RES"))) {
int res = atoi(v);
if (res >= 1 && res <= 15)
hires_res = res;
}
// "always"/"never"/"perwait" (or "auto" - same as unset)
if (!(v = getenv("MPV_HRT")) || !strcmp(v, "auto"))
v = IsWindows10OrGreater() ? "perwait" : "always";
if (!strcmp(v, "perwait")) {
// no-op, already per-wait
} else if (!strcmp(v, "never")) {
hires_max = 0;
} else { // "always" or unknown value
hires_max = 0;
timeBeginPeriod(hires_res);
}
#endif
}