[netty#1644] Fixed IndexOutOfBoundException when calling copy() on a empty CompositeByteBuf

Norman Maurer · Norman Maurer · commit 8a673db92b72 · 2013-07-24T07:35:51.000+02:00
diff --git a/buffer/src/main/java/io/netty/buffer/CompositeByteBuf.java b/buffer/src/main/java/io/netty/buffer/CompositeByteBuf.java
@@ -45,6 +45,7 @@ public class CompositeByteBuf extends AbstractReferenceCountedByteBuf {
     private final boolean direct;
     private final List<Component> components = new ArrayList<Component>();
     private final int maxNumComponents;
+    private static final ByteBuffer FULL_BYTEBUFFER = (ByteBuffer) ByteBuffer.allocate(1).position(1);
 
     private boolean freed;
 
@@ -698,6 +699,10 @@ public CompositeByteBuf getBytes(int index, ByteBuffer dst) {
     @Override
     public CompositeByteBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) {
         checkDstIndex(index, length, dstIndex, dst.capacity());
+        if (length == 0) {
+            return this;
+        }
+
         int i = toComponentIndex(index);
         while (length > 0) {
             Component c = components.get(i);
@@ -842,6 +847,9 @@ protected void _setLong(int index, long value) {
     @Override
     public CompositeByteBuf setBytes(int index, byte[] src, int srcIndex, int length) {
         checkSrcIndex(index, length, srcIndex, src.length);
+        if (length == 0) {
+            return this;
+        }
 
         int i = toComponentIndex(index);
         while (length > 0) {
@@ -864,6 +872,10 @@ public CompositeByteBuf setBytes(int index, ByteBuffer src) {
         int length = src.remaining();
 
         checkIndex(index, length);
+        if (length == 0) {
+            return this;
+        }
+
         int i = toComponentIndex(index);
         try {
             while (length > 0) {
@@ -886,6 +898,9 @@ public CompositeByteBuf setBytes(int index, ByteBuffer src) {
     @Override
     public CompositeByteBuf setBytes(int index, ByteBuf src, int srcIndex, int length) {
         checkSrcIndex(index, length, srcIndex, src.capacity());
+        if (length == 0) {
+            return this;
+        }
 
         int i = toComponentIndex(index);
         while (length > 0) {
@@ -905,6 +920,9 @@ public CompositeByteBuf setBytes(int index, ByteBuf src, int srcIndex, int lengt
     @Override
     public int setBytes(int index, InputStream in, int length) throws IOException {
         checkIndex(index, length);
+        if (length == 0) {
+            return in.read(EmptyArrays.EMPTY_BYTES);
+        }
 
         int i = toComponentIndex(index);
         int readBytes = 0;
@@ -941,6 +959,9 @@ public int setBytes(int index, InputStream in, int length) throws IOException {
     @Override
     public int setBytes(int index, ScatteringByteChannel in, int length) throws IOException {
         checkIndex(index, length);
+        if (length == 0) {
+            return in.read(FULL_BYTEBUFFER);
+        }
 
         int i = toComponentIndex(index);
         int readBytes = 0;
@@ -982,7 +1003,9 @@ public int setBytes(int index, ScatteringByteChannel in, int length) throws IOEx
     public ByteBuf copy(int index, int length) {
         checkIndex(index, length);
         ByteBuf dst = Unpooled.buffer(length);
-        copyTo(index, length, toComponentIndex(index), dst);
+        if (length != 0) {
+            copyTo(index, length, toComponentIndex(index), dst);
+        }
         return dst;
     }
 
diff --git a/buffer/src/test/java/io/netty/buffer/AbstractCompositeByteBufTest.java b/buffer/src/test/java/io/netty/buffer/AbstractCompositeByteBufTest.java
@@ -552,4 +552,18 @@ public void testRemoveLastComponent() {
         buf.removeComponent(0);
         assertEquals(0, buf.numComponents());
     }
+
+    @Test
+    public void testCopyEmpty() {
+        CompositeByteBuf buf = freeLater(compositeBuffer());
+        assertEquals(0, buf.numComponents());
+        assertEquals(0, freeLater(buf.copy()).readableBytes());
+    }
+
+    @Test
+    public void testDuplicateEmpty() {
+        CompositeByteBuf buf = freeLater(compositeBuffer());
+        assertEquals(0, buf.numComponents());
+        assertEquals(0, freeLater(buf.duplicate()).readableBytes());
+    }
 }
