Moved date_Decrement to libvlc core from dirac.

[vlc] / src / misc / mtime.c

diff --git a/src/misc/mtime.c b/src/misc/mtime.c
index afa5705c7ac7663def4e8daf92d399517d3d277d..c735bdfcaafa6721488226f8ea347f9662ec142e 100644 (file)
--- a/src/misc/mtime.c
+++ b/src/misc/mtime.c
@@ -52,14 +52,15 @@
 #   include <mmsystem.h>
 #endif
 
-#if defined( UNDER_CE )
-#   include <windows.h>
-#endif
-
 #if defined(HAVE_SYS_TIME_H)
 #   include <sys/time.h>
 #endif
 
+#ifdef __APPLE__
+#   include <mach/mach.h>
+#   include <mach/mach_time.h>
+#endif
+
 #if !defined(HAVE_STRUCT_TIMESPEC)
 struct timespec
 {
@@ -172,6 +173,15 @@ static inline unsigned mprec( void )
 #endif
 }
 
+#ifdef __APPLE__
+static mach_timebase_info_data_t mtime_timebase_info;
+static pthread_once_t mtime_timebase_info_once = PTHREAD_ONCE_INIT;
+static void mtime_init_timebase(void)
+{
+    mach_timebase_info(&mtime_timebase_info);
+}
+#endif
+
 /**
  * Return high precision date
  *
@@ -197,6 +207,16 @@ mtime_t mdate( void )
 #elif defined( HAVE_KERNEL_OS_H )
     res = real_time_clock_usecs();
 
+#elif defined( __APPLE__ )
+    pthread_once(&mtime_timebase_info_once, mtime_init_timebase);
+    uint64_t date = mach_absolute_time();
+
+    /* Convert to nanoseconds */
+    date *= mtime_timebase_info.numer;
+    date /= mtime_timebase_info.denom;
+
+    /* Convert to microseconds */
+    res = date / 1000;
 #elif defined( WIN32 ) || defined( UNDER_CE )
     /* We don't need the real date, just the value of a high precision timer */
     static mtime_t freq = INT64_C(-1);
@@ -303,6 +323,11 @@ mtime_t mdate( void )
         i_previous_time = res;
         LeaveCriticalSection( &date_lock );
     }
+#elif defined( __APPLE__ ) /* The version that should be used, if it was cancelable */
+    pthread_once(&mtime_timebase_info_once, mtime_init_timebase);
+    uint64_t mach_time = date * 1000 * mtime_timebase_info.denom / mtime_timebase_info.numer;
+    mach_wait_until(mach_time);
+
 #else
     struct timeval tv_date;
 
@@ -314,6 +339,7 @@ mtime_t mdate( void )
     return res;
 }
 
+#undef mwait
 /**
  * Wait for a date
  *
@@ -372,27 +398,6 @@ void mwait( mtime_t date )
  */
 void msleep( mtime_t delay )
 {
-#ifndef NDEBUG
-# if defined (__linux__)
-    /* We assume that proper use of msleep() will not use a constant period...
-     * Media synchronization is likely to use mwait() with at least slight
-     * sleep length variation at microsecond precision. Network protocols
-     * normally have exponential backoffs, or long delays. */
-    static __thread unsigned tick_period = 0;
-    static __thread unsigned tick_frequency = 0;
-    if (tick_period != delay)
-        tick_frequency = 0;
-    tick_frequency++;
-    tick_period = delay;
-    if (delay < (29 * CLOCK_FREQ) && tick_frequency == 20)
-    {
-         fprintf (stderr, "Likely bogus delay(%"PRIu64"µs) ", delay);
-         vlc_backtrace ();
-    }
-    //fprintf (stderr, "%u, %u\n", tick_period, tick_frequency);
-# endif
-#endif
-
 #if defined( HAVE_CLOCK_NANOSLEEP )
     lldiv_t d = lldiv( delay, 1000000 );
     struct timespec ts = { d.quot, d.rem * 1000 };
@@ -419,6 +424,11 @@ void msleep( mtime_t delay )
 
     while( nanosleep( &ts_delay, &ts_delay ) && ( errno == EINTR ) );
 
+#elif defined( __APPLE__ ) /* The version that should be used, if it was cancelable */
+    pthread_once(&mtime_timebase_info_once, mtime_init_timebase);
+    uint64_t mach_time = delay * 1000 * mtime_timebase_info.denom / mtime_timebase_info.numer;
+    mach_wait_until(mach_time + mach_absolute_time());
+
 #else
     struct timeval tv_delay;
 
@@ -526,6 +536,33 @@ mtime_t date_Increment( date_t *p_date, uint32_t i_nb_samples )
     return p_date->date;
 }
 
+/**
+ * Decrement the date and return the result, taking into account
+ * rounding errors.
+ *
+ * \param date to decrement
+ * \param decrementation in number of samples
+ * \return date value
+ */
+mtime_t date_Decrement( date_t *p_date, uint32_t i_nb_samples )
+{
+    mtime_t i_dividend = (mtime_t)i_nb_samples * 1000000 * p_date->i_divider_den;
+    p_date->date -= i_dividend / p_date->i_divider_num;
+    unsigned i_rem_adjust = i_dividend % p_date->i_divider_num;
+
+    if( p_date->i_remainder < i_rem_adjust )
+    {
+        /* This is Bresenham algorithm. */
+        assert( p_date->i_remainder > -p_date->i_divider_num);
+        p_date->date -= 1;
+        p_date->i_remainder += p_date->i_divider_num;
+    }
+
+    p_date->i_remainder -= i_rem_adjust;
+
+    return p_date->date;
+}
+
 #ifndef HAVE_GETTIMEOFDAY
 
 #ifdef WIN32