1 files changed, 267 insertions, 0 deletions
diff --git a/src/pulsecore/core-rtclock.c b/src/pulsecore/core-rtclock.c
new file mode 100644
index 0000000..2c2e286
--- /dev/null
+++ b/src/pulsecore/core-rtclock.c
@@ -0,0 +1,267 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2004-2006 Lennart Poettering
+  Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
+
+  PulseAudio 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.
+
+  PulseAudio 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 PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#ifdef OS_IS_DARWIN
+#define _POSIX_C_SOURCE 1
+#endif
+
+#include <stddef.h>
+#include <time.h>
+#include <sys/time.h>
+#include <errno.h>
+
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#endif
+
+#ifdef OS_IS_DARWIN
+#include <CoreServices/CoreServices.h>
+#include <mach/mach.h>
+#include <mach/mach_time.h>
+#include <unistd.h>
+#endif
+
+#ifdef HAVE_WINDOWS_H
+#include <windows.h>
+#endif
+
+#include <pulse/timeval.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/core-error.h>
+
+#include "core-rtclock.h"
+
+#ifdef OS_IS_WIN32
+static int64_t counter_freq = 0;
+#endif
+
+pa_usec_t pa_rtclock_age(const struct timeval *tv) {
+    struct timeval now;
+    pa_assert(tv);
+
+    return pa_timeval_diff(pa_rtclock_get(&now), tv);
+}
+
+struct timeval *pa_rtclock_get(struct timeval *tv) {
+
+#if defined(OS_IS_DARWIN)
+    uint64_t val, abs_time = mach_absolute_time();
+    Nanoseconds nanos;
+
+    nanos = AbsoluteToNanoseconds(*(AbsoluteTime *) &abs_time);
+    val = *(uint64_t *) &nanos;
+
+    tv->tv_sec = val / PA_NSEC_PER_SEC;
+    tv->tv_usec = (val % PA_NSEC_PER_SEC) / PA_NSEC_PER_USEC;
+
+    return tv;
+
+#elif defined(HAVE_CLOCK_GETTIME)
+    struct timespec ts;
+
+#ifdef CLOCK_MONOTONIC
+    /* No locking or atomic ops for no_monotonic here */
+    static bool no_monotonic = false;
+
+    if (!no_monotonic)
+        if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0)
+            no_monotonic = true;
+
+    if (no_monotonic)
+#endif /* CLOCK_MONOTONIC */
+        pa_assert_se(clock_gettime(CLOCK_REALTIME, &ts) == 0);
+
+    pa_assert(tv);
+
+    tv->tv_sec = ts.tv_sec;
+    tv->tv_usec = ts.tv_nsec / PA_NSEC_PER_USEC;
+
+    return tv;
+#elif defined(OS_IS_WIN32)
+    if (counter_freq > 0) {
+        LARGE_INTEGER count;
+
+        pa_assert_se(QueryPerformanceCounter(&count));
+
+        tv->tv_sec = count.QuadPart / counter_freq;
+        tv->tv_usec = (count.QuadPart % counter_freq) * PA_USEC_PER_SEC / counter_freq;
+
+        return tv;
+    }
+#endif /* HAVE_CLOCK_GETTIME */
+
+    return pa_gettimeofday(tv);
+}
+
+bool pa_rtclock_hrtimer(void) {
+
+#if defined (OS_IS_DARWIN)
+    mach_timebase_info_data_t tbi;
+    uint64_t time_nsec;
+
+    mach_timebase_info(&tbi);
+
+    /* nsec = nticks * (N/D) - we want 1 tick == resolution !? */
+    time_nsec = tbi.numer / tbi.denom;
+    return time_nsec <= (long) (PA_HRTIMER_THRESHOLD_USEC*PA_NSEC_PER_USEC);
+
+#elif defined(HAVE_CLOCK_GETTIME)
+    struct timespec ts;
+
+#ifdef CLOCK_MONOTONIC
+
+    if (clock_getres(CLOCK_MONOTONIC, &ts) >= 0)
+        return ts.tv_sec == 0 && ts.tv_nsec <= (long) (PA_HRTIMER_THRESHOLD_USEC*PA_NSEC_PER_USEC);
+
+#endif /* CLOCK_MONOTONIC */
+
+    pa_assert_se(clock_getres(CLOCK_REALTIME, &ts) == 0);
+    return ts.tv_sec == 0 && ts.tv_nsec <= (long) (PA_HRTIMER_THRESHOLD_USEC*PA_NSEC_PER_USEC);
+
+#elif defined(OS_IS_WIN32)
+
+    if (counter_freq > 0)
+        return counter_freq >= (int64_t) (PA_USEC_PER_SEC/PA_HRTIMER_THRESHOLD_USEC);
+
+#endif /* HAVE_CLOCK_GETTIME */
+
+    return false;
+}
+
+#define TIMER_SLACK_NS (int) ((500 * PA_NSEC_PER_USEC))
+
+void pa_rtclock_hrtimer_enable(void) {
+
+#ifdef PR_SET_TIMERSLACK
+    int slack_ns;
+
+    if ((slack_ns = prctl(PR_GET_TIMERSLACK, 0, 0, 0, 0)) < 0) {
+        pa_log_info("PR_GET_TIMERSLACK/PR_SET_TIMERSLACK not supported.");
+        return;
+    }
+
+    pa_log_debug("Timer slack is set to %i us.", (int) (slack_ns/PA_NSEC_PER_USEC));
+
+    if (slack_ns > TIMER_SLACK_NS) {
+        slack_ns = TIMER_SLACK_NS;
+
+        pa_log_debug("Setting timer slack to %i us.", (int) (slack_ns/PA_NSEC_PER_USEC));
+
+        if (prctl(PR_SET_TIMERSLACK, slack_ns, 0, 0, 0) < 0) {
+            pa_log_warn("PR_SET_TIMERSLACK failed: %s", pa_cstrerror(errno));
+            return;
+        }
+    }
+
+#elif defined(OS_IS_WIN32)
+    LARGE_INTEGER freq;
+
+    pa_assert_se(QueryPerformanceFrequency(&freq));
+    counter_freq = freq.QuadPart;
+
+#endif
+}
+
+struct timeval* pa_rtclock_from_wallclock(struct timeval *tv) {
+    struct timeval wc_now, rt_now;
+
+    pa_assert(tv);
+
+    pa_gettimeofday(&wc_now);
+    pa_rtclock_get(&rt_now);
+
+    /* pa_timeval_sub() saturates on underflow! */
+
+    if (pa_timeval_cmp(&wc_now, tv) < 0)
+        pa_timeval_add(&rt_now, pa_timeval_diff(tv, &wc_now));
+    else
+        pa_timeval_sub(&rt_now, pa_timeval_diff(&wc_now, tv));
+
+    *tv = rt_now;
+
+    return tv;
+}
+
+#ifdef HAVE_CLOCK_GETTIME
+pa_usec_t pa_timespec_load(const struct timespec *ts) {
+
+    if (PA_UNLIKELY(!ts))
+        return PA_USEC_INVALID;
+
+    return
+        (pa_usec_t) ts->tv_sec * PA_USEC_PER_SEC +
+        (pa_usec_t) ts->tv_nsec / PA_NSEC_PER_USEC;
+}
+
+struct timespec* pa_timespec_store(struct timespec *ts, pa_usec_t v) {
+    pa_assert(ts);
+
+    if (PA_UNLIKELY(v == PA_USEC_INVALID)) {
+        ts->tv_sec = PA_INT_TYPE_MAX(time_t);
+        ts->tv_nsec = (long) (PA_NSEC_PER_SEC-1);
+        return NULL;
+    }
+
+    ts->tv_sec = (time_t) (v / PA_USEC_PER_SEC);
+    ts->tv_nsec = (long) ((v % PA_USEC_PER_SEC) * PA_NSEC_PER_USEC);
+
+    return ts;
+}
+#endif
+
+static struct timeval* wallclock_from_rtclock(struct timeval *tv) {
+    struct timeval wc_now, rt_now;
+
+    pa_assert(tv);
+
+    pa_gettimeofday(&wc_now);
+    pa_rtclock_get(&rt_now);
+
+    /* pa_timeval_sub() saturates on underflow! */
+
+    if (pa_timeval_cmp(&rt_now, tv) < 0)
+        pa_timeval_add(&wc_now, pa_timeval_diff(tv, &rt_now));
+    else
+        pa_timeval_sub(&wc_now, pa_timeval_diff(&rt_now, tv));
+
+    *tv = wc_now;
+
+    return tv;
+}
+
+struct timeval* pa_timeval_rtstore(struct timeval *tv, pa_usec_t v, bool rtclock) {
+    pa_assert(tv);
+
+    if (v == PA_USEC_INVALID)
+        return NULL;
+
+    pa_timeval_store(tv, v);
+
+    if (rtclock)
+        tv->tv_usec |= PA_TIMEVAL_RTCLOCK;
+    else
+        wallclock_from_rtclock(tv);
+
+    return tv;
+}