[Cronet] Fix CronetHttpURLConnection#getResponse() hang

components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.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.net.urlconnection;
 
 import android.util.Pair;
 
 import org.chromium.base.Log;
 import org.chromium.net.CronetEngine;
@@ skipping 27 matching lines @@
     private static final String CONTENT_LENGTH = "Content-Length";
     private final CronetEngine mCronetEngine;
     private final MessageLoop mMessageLoop;
     private UrlRequest mRequest;
     private final List<Pair<String, String>> mRequestHeaders;
 
     private CronetInputStream mInputStream;
     private CronetOutputStream mOutputStream;
     private UrlResponseInfo mResponseInfo;
     private CronetException mException;
-    private boolean mOnRedirectCalled = false;
-    private boolean mHasResponse = false;
+    private boolean mOnRedirectCalled;
+    // Whether response headers are received, the request is failed, or the request is canceled.
+    private boolean mHasResponseHeadersOrCompleted;
     private List<Map.Entry<String, String>> mResponseHeadersList;
     private Map<String, List<String>> mResponseHeadersMap;
 
     public CronetHttpURLConnection(URL url, CronetEngine cronetEngine) {
         super(url);
         mCronetEngine = cronetEngine;
         mMessageLoop = new MessageLoop();
         mInputStream = new CronetInputStream(this);
         mRequestHeaders = new ArrayList<Pair<String, String>>();
     }
@@ skipping 370 matching lines @@
         }
         return -1;
     }
 
     private class CronetUrlRequestCallback extends UrlRequest.Callback {
         public CronetUrlRequestCallback() {}
 
         @Override
         public void onResponseStarted(UrlRequest request, UrlResponseInfo info) {
             mResponseInfo = info;
+            mHasResponseHeadersOrCompleted = true;
             // Quits the message loop since we have the headers now.
             mMessageLoop.quit();
         }
 
         @Override
         public void onReadCompleted(
                 UrlRequest request, UrlResponseInfo info, ByteBuffer byteBuffer) {
             mResponseInfo = info;
             mMessageLoop.quit();
         }
@@ skipping 51 matching lines @@
          * @param exception if not {@code null}, it is the exception to report when
          *            caller tries to read more data.
          */
         private void setResponseDataCompleted(IOException exception) {
             if (mInputStream != null) {
                 mInputStream.setResponseDataCompleted(exception);
             }
             if (mOutputStream != null) {
                 mOutputStream.setRequestCompleted(exception);
             }
-            mHasResponse = true;
+            mHasResponseHeadersOrCompleted = true;
             mMessageLoop.quit();
         }
     }
 
     /**
      * Blocks until the respone headers are received.
      */
     private void getResponse() throws IOException {
         // Check to see if enough data has been received.
         if (mOutputStream != null) {
             mOutputStream.checkReceivedEnoughContent();
             if (isChunkedUpload()) {
                 // Write last chunk.
                 mOutputStream.close();
             }
         }
-        if (!mHasResponse) {
+        if (!mHasResponseHeadersOrCompleted) {
             startRequest();
             // Blocks until onResponseStarted or onFailed is called.
             mMessageLoop.loop();
-            mHasResponse = true;
         }
-        checkHasResponse();
+        checkHasResponseHeaders();
     }
 
     /**
      * Checks whether response headers are received, and throws an exception if
      * an exception occurred before headers received. This method should only be
      * called after onResponseStarted or onFailed.
      */
-    private void checkHasResponse() throws IOException {
-        if (!mHasResponse) throw new IllegalStateException("No response.");
+    private void checkHasResponseHeaders() throws IOException {
+        if (!mHasResponseHeadersOrCompleted) throw new IllegalStateException("No response.");
         if (mException != null) {
             throw mException;
         } else if (mResponseInfo == null) {
             throw new NullPointerException(
                     "Response info is null when there is no exception.");
         }
     }
 
     /**
      * Helper method to return the response header field at position pos.
@@ skipping 46 matching lines @@
             // Strips Content-Encoding response header. See crbug.com/592700.
             if (!entry.getKey().equalsIgnoreCase("Content-Encoding")) {
                 mResponseHeadersList.add(
                         new AbstractMap.SimpleImmutableEntry<String, String>(entry));
             }
         }
         mResponseHeadersList = Collections.unmodifiableList(mResponseHeadersList);
         return mResponseHeadersList;
     }
 }