Compute empty byte address at runtime quarkusio#9750

galderz · Jun 5, 2020 · 23e8e8f · 23e8e8f
1 parent 4182a75
commit 23e8e8f
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Showing 2 changed files with 35 additions and 2 deletions.
diff --git a/extensions/netty/runtime/src/main/java/io/quarkus/netty/runtime/EmptyByteBufStub.java b/extensions/netty/runtime/src/main/java/io/quarkus/netty/runtime/EmptyByteBufStub.java
@@ -2,13 +2,32 @@
 
 import java.nio.ByteBuffer;
 
+import io.netty.util.internal.PlatformDependent;
+
 public final class EmptyByteBufStub {
     private static final ByteBuffer EMPTY_BYTE_BUFFER = ByteBuffer.allocateDirect(0);
+    private static final long EMPTY_BYTE_BUFFER_ADDRESS;
+
+    static {
+        long emptyByteBufferAddress = 0;
+        try {
+            if (PlatformDependent.hasUnsafe()) {
+                emptyByteBufferAddress = PlatformDependent.directBufferAddress(EMPTY_BYTE_BUFFER);
+            }
+        } catch (Throwable t) {
+            // Ignore
+        }
+        EMPTY_BYTE_BUFFER_ADDRESS = emptyByteBufferAddress;
+    }
 
     public static ByteBuffer emptyByteBuffer() {
         return EMPTY_BYTE_BUFFER;
     }
 
+    public static long emptyByteBufferAddress() {
+        return EMPTY_BYTE_BUFFER_ADDRESS;
+    }
+
     private EmptyByteBufStub() {
     }
 }
diff --git a/...nsions/netty/runtime/src/main/java/io/quarkus/netty/runtime/graal/NettySubstitutions.java b/...nsions/netty/runtime/src/main/java/io/quarkus/netty/runtime/graal/NettySubstitutions.java
@@ -399,8 +399,8 @@ final class Target_io_netty_buffer_EmptyByteBuf {
     private static ByteBuffer EMPTY_BYTE_BUFFER;
 
     @Alias
-    @RecomputeFieldValue(kind = RecomputeFieldValue.Kind.FromAlias)
-    private static long EMPTY_BYTE_BUFFER_ADDRESS = 0;
+    @RecomputeFieldValue(kind = RecomputeFieldValue.Kind.Reset)
+    private static long EMPTY_BYTE_BUFFER_ADDRESS;
 
     @Substitute
     public ByteBuffer nioBuffer() {
@@ -417,6 +417,20 @@ public ByteBuffer internalNioBuffer(int index, int length) {
         return EmptyByteBufStub.emptyByteBuffer();
     }
 
+    @Substitute
+    public boolean hasMemoryAddress() {
+        return EmptyByteBufStub.emptyByteBufferAddress() != 0;
+    }
+
+    @Substitute
+    public long memoryAddress() {
+        if (hasMemoryAddress()) {
+            return EmptyByteBufStub.emptyByteBufferAddress();
+        } else {
+            throw new UnsupportedOperationException();
+        }
+    }
+
 }
 
 class NettySubstitutions {