mojo: Validate fixed size array for the mojo java bindings.

mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java

Index: mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
diff --git a/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java b/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
index 49fb1fdcef0c675f8538b0922d21b5a40ac05c4f..8c69b9219e703314740b4baca1ce11627e1111c7 100644
--- a/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
+++ b/mojo/public/java/bindings/src/org/chromium/mojo/bindings/Decoder.java
@@ -128,6 +128,21 @@ public class Decoder {
     }
 
     /**
+     * Deserializes a {@link DataHeader} of an array at the given offset.
+     *
+     * @param expectedLength the expected length of the array.
+     */
+    public DataHeader readArrayDataHeader(int expectedLength) {
+        DataHeader dataHeader = readDataHeader();
+        if (expectedLength != BindingsHelper.UNSPECIFIED_ARRAY_LENGTH
+                && dataHeader.numFields != expectedLength) {
+            throw new DeserializationException("Incorrect array length. Expected: " +
+                    expectedLength + ", but got: " + dataHeader.numFields + ".");
+        }
+        return dataHeader;
+    }
+
+    /**
      * Deserializes a byte at the given offset.
      */
     public byte readByte(int offset) {
@@ -199,12 +214,12 @@ public class Decoder {
     /**
      * Deserializes an array of boolean at the given offset.
      */
-    public boolean[] readBooleans(int offset, int arrayNullability) {
+    public boolean[] readBooleans(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         byte[] bytes = new byte[si.numFields + 7 / BindingsHelper.ALIGNMENT];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.get(bytes);
@@ -223,12 +238,12 @@ public class Decoder {
     /**
      * Deserializes an array of bytes at the given offset.
      */
-    public byte[] readBytes(int offset, int arrayNullability) {
+    public byte[] readBytes(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         byte[] result = new byte[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.get(result);
@@ -238,12 +253,12 @@ public class Decoder {
     /**
      * Deserializes an array of shorts at the given offset.
      */
-    public short[] readShorts(int offset, int arrayNullability) {
+    public short[] readShorts(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         short[] result = new short[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asShortBuffer().get(result);
@@ -253,12 +268,12 @@ public class Decoder {
     /**
      * Deserializes an array of ints at the given offset.
      */
-    public int[] readInts(int offset, int arrayNullability) {
+    public int[] readInts(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         int[] result = new int[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asIntBuffer().get(result);
@@ -268,12 +283,12 @@ public class Decoder {
     /**
      * Deserializes an array of floats at the given offset.
      */
-    public float[] readFloats(int offset, int arrayNullability) {
+    public float[] readFloats(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         float[] result = new float[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asFloatBuffer().get(result);
@@ -283,12 +298,12 @@ public class Decoder {
     /**
      * Deserializes an array of longs at the given offset.
      */
-    public long[] readLongs(int offset, int arrayNullability) {
+    public long[] readLongs(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         long[] result = new long[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asLongBuffer().get(result);
@@ -298,12 +313,12 @@ public class Decoder {
     /**
      * Deserializes an array of doubles at the given offset.
      */
-    public double[] readDoubles(int offset, int arrayNullability) {
+    public double[] readDoubles(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         double[] result = new double[si.numFields];
         d.mMessage.buffer.position(d.mBaseOffset + DataHeader.HEADER_SIZE);
         d.mMessage.buffer.asDoubleBuffer().get(result);
@@ -392,7 +407,7 @@ public class Decoder {
      */
     public String readString(int offset, boolean nullable) {
         final int arrayNullability = nullable ? BindingsHelper.ARRAY_NULLABLE : 0;
-        byte[] bytes = readBytes(offset, arrayNullability);
+        byte[] bytes = readBytes(offset, arrayNullability, BindingsHelper.UNSPECIFIED_ARRAY_LENGTH);
         if (bytes == null) {
             return null;
         }
@@ -402,12 +417,12 @@ public class Decoder {
     /**
      * Deserializes an array of |Handle| at the given offset.
      */
-    public Handle[] readHandles(int offset, int arrayNullability) {
+    public Handle[] readHandles(int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         Handle[] result = new Handle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readHandle(
@@ -420,12 +435,13 @@ public class Decoder {
     /**
      * Deserializes an array of |UntypedHandle| at the given offset.
      */
-    public UntypedHandle[] readUntypedHandles(int offset, int arrayNullability) {
+    public UntypedHandle[] readUntypedHandles(
+            int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         UntypedHandle[] result = new UntypedHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readUntypedHandle(
@@ -438,12 +454,13 @@ public class Decoder {
     /**
      * Deserializes an array of |ConsumerHandle| at the given offset.
      */
-    public DataPipe.ConsumerHandle[] readConsumerHandles(int offset, int arrayNullability) {
+    public DataPipe.ConsumerHandle[] readConsumerHandles(
+            int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         DataPipe.ConsumerHandle[] result = new DataPipe.ConsumerHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readConsumerHandle(
@@ -456,12 +473,13 @@ public class Decoder {
     /**
      * Deserializes an array of |ProducerHandle| at the given offset.
      */
-    public DataPipe.ProducerHandle[] readProducerHandles(int offset, int arrayNullability) {
+    public DataPipe.ProducerHandle[] readProducerHandles(
+            int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         DataPipe.ProducerHandle[] result = new DataPipe.ProducerHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readProducerHandle(
@@ -475,12 +493,13 @@ public class Decoder {
     /**
      * Deserializes an array of |MessagePipeHandle| at the given offset.
      */
-    public MessagePipeHandle[] readMessagePipeHandles(int offset, int arrayNullability) {
+    public MessagePipeHandle[] readMessagePipeHandles(
+            int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         MessagePipeHandle[] result = new MessagePipeHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readMessagePipeHandle(
@@ -494,12 +513,13 @@ public class Decoder {
     /**
      * Deserializes an array of |SharedBufferHandle| at the given offset.
      */
-    public SharedBufferHandle[] readSharedBufferHandles(int offset, int arrayNullability) {
+    public SharedBufferHandle[] readSharedBufferHandles(
+            int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         SharedBufferHandle[] result = new SharedBufferHandle[si.numFields];
         for (int i = 0; i < result.length; ++i) {
             result[i] = d.readSharedBufferHandle(
@@ -513,13 +533,13 @@ public class Decoder {
     /**
      * Deserializes an array of |ServiceHandle| at the given offset.
      */
-    public <S extends Interface, P extends Proxy> S[] readServiceInterfaces(int offset,
-            int arrayNullability, Interface.Manager<S, P> manager) {
+    public <S extends Interface, P extends Proxy> S[] readServiceInterfaces(
+            int offset, int arrayNullability, int expectedLength, Interface.Manager<S, P> manager) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         S[] result = manager.buildArray(si.numFields);
         for (int i = 0; i < result.length; ++i) {
             // This cast is necessary because java 6 doesn't handle wildcard correctly when using
@@ -536,13 +556,13 @@ public class Decoder {
     /**
      * Deserializes an array of |InterfaceRequest| at the given offset.
      */
-    public <I extends Interface> InterfaceRequest<I>[] readInterfaceRequests(int offset,
-            int arrayNullability) {
+    public <I extends Interface> InterfaceRequest<I>[] readInterfaceRequests(
+            int offset, int arrayNullability, int expectedLength) {
         Decoder d = readPointer(offset, BindingsHelper.isArrayNullable(arrayNullability));
         if (d == null) {
             return null;
         }
-        DataHeader si = d.readDataHeader();
+        DataHeader si = d.readArrayDataHeader(expectedLength);
         @SuppressWarnings("unchecked")
         InterfaceRequest<I>[] result = new InterfaceRequest[si.numFields];
         for (int i = 0; i < result.length; ++i) {