Initialize BufferManager from within Mixer

Avoid crashes caused by worker threads accessing the buffer manager
before it is initialized. Therefore initialize it from within the
Mixer constructor which has the side effect that it gets initialized
in console-only rendering mode as well.

src/core/BufferManager.cpp

@@ -34,18 +34,18 @@ QAtomicInt BufferManager::s_releasedIndex = 0;
 int BufferManager::s_size;
 
 
-void BufferManager::init()
+void BufferManager::init( fpp_t framesPerPeriod )
 {
 	s_available = MM_ALLOC( sampleFrame*, BM_INITIAL_BUFFERS );
 	s_released = MM_ALLOC( sampleFrame*, BM_INITIAL_BUFFERS );
 
-	int c = engine::mixer()->framesPerPeriod() * BM_INITIAL_BUFFERS;
+	int c = framesPerPeriod * BM_INITIAL_BUFFERS;
 	sampleFrame * b = MM_ALLOC( sampleFrame, c );
 	
 	for( int i = 0; i < BM_INITIAL_BUFFERS; ++i )
 	{
 		s_available[ i ] = b;
-		b += engine::mixer()->framesPerPeriod();
+		b += framesPerPeriod;
 	}
 	s_availableIndex = BM_INITIAL_BUFFERS - 1;
 	s_size = BM_INITIAL_BUFFERS;

src/core/Mixer.cpp

@@ -118,6 +118,9 @@ Mixer::Mixer() :
 		m_fifo = new fifo( 1 );
 	}
 
+	// now that framesPerPeriod is fixed initialize global BufferManager
+	BufferManager::init( m_framesPerPeriod );
+
 	m_workingBuf = (sampleFrame*) MemoryHelper::alignedMalloc( m_framesPerPeriod *
 							sizeof( sampleFrame ) );
 	for( int i = 0; i < 3; i++ )

src/core/main.cpp

@@ -76,7 +76,6 @@
 #include "DataFile.h"
 #include "song.h"
 #include "LmmsPalette.h"
-#include "BufferManager.h"
 
 static inline QString baseName( const QString & _file )
 {
@@ -440,9 +439,6 @@ int main( int argc, char * * argv )
 		// init central engine which handles all components of LMMS
 		engine::init();
 		
-		// init buffer manager - has to be done after fpp is known
-		BufferManager::init();
-
 		splashScreen.hide();
 
 		// re-intialize RNG - shared libraries might have srand() or
@@ -509,6 +505,7 @@ int main( int argc, char * * argv )
 	{
 		// we're going to render our song
 		engine::init( false );
+
 		printf( "loading project...\n" );
 		engine::getSong()->loadProject( file_to_load );
 		printf( "done\n" );