Attempt to cut out a lot of synchronized calls

A lot of these don't actually have any effect as they'll only be called
on the main thread or they are getters where the state is guaranteed to
be consistent whenever it is accessed.

Hopefully this'll reduce the chance of world updates being blocked by
waiting for peripheral locks to be released.

src/main/java/dan200/computercraft/shared/peripheral/common/TilePeripheralBase.java

@@ -112,12 +112,12 @@ public abstract class TilePeripheralBase extends TileGeneric
         }
     }
 
-    public synchronized int getAnim()
+    public int getAnim()
     {
         return m_anim;
     }
     
-    public synchronized void setAnim( int anim )
+    public void setAnim( int anim )
     {
         if( anim != m_anim )
         {
@@ -127,12 +127,12 @@ public abstract class TilePeripheralBase extends TileGeneric
     }
 
     @Override    
-    public synchronized void update()
+    public void update()
     {
         if( m_changed )
         {
-            updateBlock();
             m_changed = false;
+            updateBlock();
         }
     }
             

src/main/java/dan200/computercraft/shared/peripheral/diskdrive/TileDiskDrive.java

@@ -80,12 +80,9 @@ public class TileDiskDrive extends TilePeripheralBase
     public void destroy()
     {
         ejectContents( true );
-        synchronized( this )
+        if( m_recordPlaying )
         {
-            if( m_recordPlaying )
-            {
-                stopRecord();
-            }
+            stopRecord();
         }
     }
 
@@ -170,13 +167,10 @@ public class TileDiskDrive extends TilePeripheralBase
         super.update();
 
         // Ejection
-        synchronized( this )
+        if( m_ejectQueued )
         {
-            if( m_ejectQueued )
-            {
-                ejectContents( false );
-                m_ejectQueued = false;
-            }
+            ejectContents( false );
+            m_ejectQueued = false;
         }
         
         // Music
@@ -391,10 +385,7 @@ public class TileDiskDrive extends TilePeripheralBase
     @Override
     public void clear()
     {
-        synchronized( this )
-        {
-            setInventorySlotContents( 0, ItemStack.EMPTY );
-        }
+        setInventorySlotContents( 0, ItemStack.EMPTY );
     }
 
     @Override
@@ -425,18 +416,12 @@ public class TileDiskDrive extends TilePeripheralBase
     @Nonnull
     public ItemStack getDiskStack()
     {
-        synchronized( this )
-        {
-            return getStackInSlot( 0 );
-        }
+        return getStackInSlot( 0 );
     }
 
     public void setDiskStack( @Nonnull ItemStack stack )
     {
-        synchronized( this )
-        {
-            setInventorySlotContents( 0, stack );
-        }
+        setInventorySlotContents( 0, stack );
     }
 
     public IMedia getDiskMedia()
@@ -569,7 +554,7 @@ public class TileDiskDrive extends TilePeripheralBase
         }
     }
 
-    private synchronized void updateAnim()
+    private void updateAnim()
     {            
         if( !m_diskStack.isEmpty() )
         {

src/main/java/dan200/computercraft/shared/peripheral/modem/ModemPeripheral.java

@@ -75,7 +75,7 @@ public abstract class ModemPeripheral
         m_open = false;
     }
     
-    public synchronized boolean pollChanged()
+    public boolean pollChanged()
     {
         if( m_changed )
         {
@@ -85,9 +85,9 @@ public abstract class ModemPeripheral
         return false;
     }
 
-    public synchronized boolean isActive()
+    public boolean isActive()
     {
-        return (m_computer != null) && m_open;
+        return m_computer != null && m_open;
     }
 
     @Override

src/main/java/dan200/computercraft/shared/peripheral/modem/TileModemBase.java

@@ -37,7 +37,7 @@ public abstract class TileModemBase extends TilePeripheralBase
     protected abstract ModemPeripheral createPeripheral();
             
     @Override
-    public synchronized void destroy()
+    public void destroy()
     {
         if( m_modem != null )
         {

src/main/java/dan200/computercraft/shared/peripheral/printer/TilePrinter.java

@@ -190,10 +190,7 @@ public class TilePrinter extends TilePeripheralBase
     @Override    
     public ItemStack getStackInSlot(int i)
     {
-        synchronized( m_inventory )
-        {
-            return m_inventory.get( i );
-        }
+        return m_inventory.get( i );
     }
 
     @Nonnull

src/main/java/dan200/computercraft/shared/peripheral/speaker/SpeakerPeripheral.java

@@ -20,6 +20,7 @@ import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import static dan200.computercraft.core.apis.ArgumentHelper.getString;
 import static dan200.computercraft.core.apis.ArgumentHelper.optReal;
@@ -28,13 +29,13 @@ public class SpeakerPeripheral implements IPeripheral {
     private TileSpeaker m_speaker;
     private long m_clock;
     private long m_lastPlayTime;
-    private int m_notesThisTick;
+    private final AtomicInteger m_notesThisTick;
 
     public SpeakerPeripheral()
     {
         m_clock = 0;
         m_lastPlayTime = 0;
-        m_notesThisTick = 0;
+        m_notesThisTick = new AtomicInteger(  );
     }
 
     SpeakerPeripheral(TileSpeaker speaker)
@@ -43,10 +44,10 @@ public class SpeakerPeripheral implements IPeripheral {
         m_speaker = speaker;
     }
 
-    public synchronized void update()
+    public void update()
     {
         m_clock++;
-        m_notesThisTick = 0;
+        m_notesThisTick.set( 0 );
     }
 
     public World getWorld()
@@ -59,9 +60,9 @@ public class SpeakerPeripheral implements IPeripheral {
         return m_speaker.getPos();
     }
 
-    public synchronized boolean madeSound(long ticks)
+    public boolean madeSound(long ticks)
     {
-        return (m_clock - m_lastPlayTime <= ticks) ;
+        return m_clock - m_lastPlayTime <= ticks;
     }
 
     /* IPeripheral implementation */
@@ -146,7 +147,7 @@ public class SpeakerPeripheral implements IPeripheral {
 
         if( returnValue[0] instanceof Boolean && (Boolean) returnValue[0] )
         {
-            m_notesThisTick++;
+            m_notesThisTick.incrementAndGet();
         }
 
         return returnValue;
@@ -161,7 +162,7 @@ public class SpeakerPeripheral implements IPeripheral {
 
         ResourceLocation resourceName = new ResourceLocation( name );
 
-        if( m_clock - m_lastPlayTime >= TileSpeaker.MIN_TICKS_BETWEEN_SOUNDS || ( ( m_clock - m_lastPlayTime == 0 ) && ( m_notesThisTick < ComputerCraft.maxNotesPerTick ) && isNote ) )
+        if( m_clock - m_lastPlayTime >= TileSpeaker.MIN_TICKS_BETWEEN_SOUNDS || (isNote && m_clock - m_lastPlayTime == 0 && m_notesThisTick.get() < ComputerCraft.maxNotesPerTick) )
         {
             if( SoundEvent.REGISTRY.containsKey(resourceName) )
             {

src/main/java/dan200/computercraft/shared/peripheral/speaker/TileSpeaker.java

@@ -25,7 +25,7 @@ public class TileSpeaker extends TilePeripheralBase
     }
 
     @Override
-    public synchronized void update()
+    public void update()
     {
         m_peripheral.update();
     }