Fix Android for positive MojoResults.

mojo/android/system/src/org/chromium/mojo/system/impl/CoreImpl.java

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.mojo.system.impl;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 import org.chromium.mojo.system.AsyncWaiter;
 import org.chromium.mojo.system.Core;
@@ skipping 308 matching lines @@
         }
         return result;
     }
 
     /**
      * @see ConsumerHandle#discardData(int, DataPipe.ReadFlags)
      */
     int discardData(DataPipeConsumerHandleImpl handle, int numBytes, DataPipe.ReadFlags flags) {
         int result = nativeReadData(handle.getMojoHandle(), null, numBytes,
                 flags.getFlags() | MOJO_READ_DATA_FLAG_DISCARD);
-        if (result < 0) {
+        if (result != MojoResult.OK) {
             throw new MojoException(result);
         }
         return result;

[viettrungluu, 2015/04/02 23:02:42]

This should always be MojoResult.OK, I think.

     }
 
     /**
      * @see ConsumerHandle#readData(ByteBuffer, DataPipe.ReadFlags)
      */
     int readData(DataPipeConsumerHandleImpl handle, ByteBuffer elements, DataPipe.ReadFlags flags) {
         int result = nativeReadData(handle.getMojoHandle(), elements,
                 elements == null ? 0 : elements.capacity(), flags.getFlags());
-        if (result < 0) {
+        if (result != MojoResult.OK) {
             throw new MojoException(result);
         }
         if (elements != null) {
             elements.limit(result);
         }
         return result;

[viettrungluu, 2015/04/02 23:02:42]

This is obviously wrong (and hence nativeReadData() is wrong).

     }
 
     /**
      * @see ConsumerHandle#beginReadData(int, DataPipe.ReadFlags)
      */
     ByteBuffer beginReadData(
             DataPipeConsumerHandleImpl handle, int numBytes, DataPipe.ReadFlags flags) {
         NativeCodeAndBufferResult result =
                 nativeBeginReadData(handle.getMojoHandle(), numBytes, flags.getFlags());
         if (result.getMojoResult() != MojoResult.OK) {
@@ skipping 211 matching lines @@
         NativeCodeAndBufferResult result = new NativeCodeAndBufferResult();
         result.setMojoResult(mojoResult);
         result.setBuffer(buffer);
         return result;
     }
 
     @CalledByNative
     private static MessagePipeHandle.ReadMessageResult newReadMessageResult(
             int mojoResult, int messageSize, int handlesCount) {
         MessagePipeHandle.ReadMessageResult result = new MessagePipeHandle.ReadMessageResult();
-        if (mojoResult >= 0) {
-            result.setMojoResult(MojoResult.OK);
-        } else {
-            result.setMojoResult(mojoResult);
-        }
+        result.setMojoResult(MojoResult.OK);
         result.setMessageSize(messageSize);
         result.setHandlesCount(handlesCount);
         return result;
     }
 
     private static class NativeCreationResult {
         private int mMojoResult;
         private int mMojoHandle1;
         private int mMojoHandle2;
 
@@ skipping 91 matching lines @@
     private native NativeCodeAndBufferResult nativeMap(
             int mojoHandle, long offset, long numBytes, int flags);
 
     private native int nativeUnmap(ByteBuffer buffer);
 
     private native AsyncWaiterCancellableImpl nativeAsyncWait(
             int mojoHandle, int signals, long deadline, AsyncWaiter.Callback callback);
 
     private native void nativeCancelAsyncWait(long mId, long dataPtr);
 }