putative fix for crashes related to diskstream playback buffer refills with compound regions

git-svn-id: svn://localhost/ardour2/branches/3.0@9620 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/ardour/ardour/audiosource.h

@@ -106,7 +106,7 @@ class AudioSource : virtual public Source,
 	/** @return true if the each source sample s must be clamped to -1 < s < 1 */
 	virtual bool clamped_at_unity () const = 0;
 
-	static void allocate_working_buffers ();
+	static void allocate_working_buffers (framecnt_t framerate);
     
   protected:
 	static bool _build_missing_peakfiles;
@@ -124,7 +124,7 @@ class AudioSource : virtual public Source,
 	static std::vector<gain_t*> _gain_buffers;
 	static Glib::StaticMutex    _level_buffer_lock;
 
-	static void ensure_buffers_for_level (uint32_t);
+	static void ensure_buffers_for_level (uint32_t, framecnt_t);
 
 	framecnt_t           _length;
 	std::string         peakpath;

libs/ardour/audio_playlist_source.cc

@@ -54,7 +54,7 @@ AudioPlaylistSource::AudioPlaylistSource (Session& s, const ID& orig, const std:
 	, _playlist_channel (chn)
 {
 	AudioSource::_length = len;
-	ensure_buffers_for_level (_level);
+	ensure_buffers_for_level (_level, _session.frame_rate());
 }
 
 AudioPlaylistSource::AudioPlaylistSource (Session& s, const XMLNode& node)
@@ -122,7 +122,7 @@ AudioPlaylistSource::set_state (const XMLNode& node, int version, bool with_desc
 
 	sscanf (prop->value().c_str(), "%" PRIu32, &_playlist_channel);
 
-	ensure_buffers_for_level (_level);
+	ensure_buffers_for_level (_level, _session.frame_rate());
 
 	return 0;
 }

libs/ardour/audioregion.cc

@@ -384,17 +384,6 @@ AudioRegion::_read_at (const SourceList& /*srcs*/, framecnt_t limit,
 	framecnt_t to_read;
 	bool raw = (rops == ReadOpsNone);
 
-	cerr << name() << " _read_at, limit = " << limit
-	     << " pos " << position 
-	     << " cnt " << cnt
-	     << " chan " << chan_n
-	     << " rops " << hex << rops << dec
-	     << endl;
-	
-	if (cnt > 64 * 1024) {
-		abort ();
-	}
-
 	if (n_channels() == 0) {
 		return 0;
 	}

libs/ardour/audiosource.cc

@@ -965,24 +965,45 @@ AudioSource::mark_streaming_write_completed ()
 }
 
 void
-AudioSource::allocate_working_buffers()
+AudioSource::allocate_working_buffers (framecnt_t framerate)
 {
-	assert(AudioDiskstream::disk_io_frames() > 0);
-	_working_buffers_size = AudioDiskstream::disk_io_frames();
-	/* we don't need any buffers allocated until
+	uint32_t current_level;
+	
+	{
+		Glib::Mutex::Lock lm (_level_buffer_lock);
+		current_level = _mixdown_buffers.size();
+	}
+
+	/* Note: we don't need any buffers allocated until
 	   a level 1 audiosource is created, at which
 	   time we'll call ::ensure_buffers_for_level()
 	   with the right value and do the right thing.
 	*/
+	
+	if (current_level) {
+		ensure_buffers_for_level (current_level, framerate);
+	}
 }
 
 void
-AudioSource::ensure_buffers_for_level (uint32_t level) 
+AudioSource::ensure_buffers_for_level (uint32_t level, framecnt_t frame_rate) 
 {
+	framecnt_t nframes = (framecnt_t) floor (Config->get_audio_playback_buffer_seconds() * frame_rate);
+
+	cerr << "audiosource: allocate buffers for level " << level << " size = " << nframes << endl;
+
 	Glib::Mutex::Lock lm (_level_buffer_lock);
 
+	/* this will leak memory. oh well. rather complex
+	   to stop it from doing that without using shared_ptrs,
+	   which i might do next. paul - may 27th 2011
+	 */
+
+	_mixdown_buffers.clear ();
+	_gain_buffers.clear ();
+
 	while (_mixdown_buffers.size() < level) {
-		_mixdown_buffers.push_back (new Sample[_working_buffers_size]);
-		_gain_buffers.push_back (new gain_t[_working_buffers_size]);
+		_mixdown_buffers.push_back (new Sample[nframes]);
+		_gain_buffers.push_back (new gain_t[nframes]);
 	}
 }

libs/ardour/session_state.cc

@@ -221,7 +221,6 @@ Session::first_stage_init (string fullpath, string snapshot_name)
         _speakers.reset (new Speakers);
 
 	AudioDiskstream::allocate_working_buffers();
-	AudioSource::allocate_working_buffers ();
 
 	/* default short fade = 15ms */
 
@@ -3559,6 +3558,8 @@ Session::config_changed (std::string p, bool ours)
 		solo_control_mode_changed ();
 	} else if (p == "timecode-offset" || p == "timecode-offset-negative") {
 		last_timecode_valid = false;
+	} else if (p == "playback-buffer-seconds") {
+		AudioSource::allocate_working_buffers (frame_rate());
 	}
 
 	set_dirty ();