Fix impossible delay

[vlc] / include / vlc_mtime.h

diff --git a/include/vlc_mtime.h b/include/vlc_mtime.h
index 30460698c6015d98df51c6ba1ae109139b168667..49f53ca658680953c0f88bd5e33832536c3ec5ed 100644 (file)
--- a/include/vlc_mtime.h
+++ b/include/vlc_mtime.h
@@ -29,9 +29,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  *****************************************************************************/
 
-#if !defined( __LIBVLC__ )
-  #error You are not libvlc or one of its plugins. You cannot include this file
-#endif
+#ifndef __VLC_MTIME_H
+# define __VLC_MTIME_H 1
 
 /*****************************************************************************
  * LAST_MDATE: date which will never happen
@@ -69,6 +68,57 @@ VLC_EXPORT( void,    mwait,    ( mtime_t date ) );
 VLC_EXPORT( void,    msleep,   ( mtime_t delay ) );
 VLC_EXPORT( char *,  secstotimestr, ( char *psz_buffer, int secs ) );
 
+#if defined (__GNUC__) && defined (__linux__)
+# define VLC_HARD_MIN_SLEEP 10000 /* Linux has 100, 250, 300 or 1000Hz */
+# define VLC_SOFT_MIN_SLEEP 9000000
+
+static
+__attribute__((unused))
+__attribute__((noinline))
+__attribute__((error("sorry, cannot sleep for such short a time")))
+mtime_t impossible_delay( mtime_t delay )
+{
+    (void) delay;
+    return VLC_HARD_MIN_SLEEP;
+}
+
+static
+__attribute__((unused))
+__attribute__((noinline))
+__attribute__((warning("use proper event handling instead of short delay")))
+mtime_t harmful_delay( mtime_t delay )
+{
+    return delay;
+}
+
+# define check_delay( d ) \
+    ((__builtin_constant_p(d < VLC_HARD_MIN_SLEEP) \
+   && (d < VLC_HARD_MIN_SLEEP)) \
+       ? impossible_delay(d) \
+       : ((__builtin_constant_p(d < VLC_SOFT_MIN_SLEEP) \
+       && (d < VLC_SOFT_MIN_SLEEP)) \
+           ? harmful_delay(d) \
+           : d))
+
+static
+__attribute__((unused))
+__attribute__((noinline))
+__attribute__((error("deadlines can not be constant")))
+mtime_t impossible_deadline( mtime_t deadline )
+{
+    return deadline;
+}
+
+# define check_deadline( d ) \
+    (__builtin_constant_p(d) ? impossible_deadline(d) : d)
+#else
+# define check_delay(d) (d)
+# define check_deadline(d) (d)
+#endif
+
+#define msleep(d) msleep(check_delay(d))
+#define mwait(d) mwait(check_deadline(d))
+
 /*****************************************************************************
  * date_t: date incrementation without long-term rounding errors
  *****************************************************************************/
@@ -86,3 +136,6 @@ VLC_EXPORT( void,    date_Set,       ( date_t *, mtime_t ) );
 VLC_EXPORT( mtime_t, date_Get,       ( const date_t * ) );
 VLC_EXPORT( void,    date_Move,      ( date_t *, mtime_t ) );
 VLC_EXPORT( mtime_t, date_Increment, ( date_t *, uint32_t ) );
+VLC_EXPORT( mtime_t, date_Decrement, ( date_t *, uint32_t ) );
+VLC_EXPORT( uint64_t, NTPtime64,     ( void ) );
+#endif /* !__VLC_MTIME_ */