[Cronet] Do not call into native adapter after it is destroyed in ChromiumUrlRequest.java

components/cronet/android/java/src/org/chromium/net/ChromiumUrlRequest.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;
 
 import android.util.Log;
 
 import org.apache.http.conn.ConnectTimeoutException;
 import org.chromium.base.CalledByNative;
@@ skipping 43 matching lines @@
     private long mUploadContentLength;
     private final HttpUrlRequestListener mListener;
     private boolean mBufferFullResponse;
     private long mOffset;
     private long mContentLength;
     private long mContentLengthLimit;
     private boolean mCancelIfContentLengthOverLimit;
     private boolean mContentLengthOverLimit;
     private boolean mSkippingToOffset;
     private long mSize;
+
     // Indicates whether redirects have been disabled.
     private boolean mDisableRedirects;
+
+    // Caches the http status code. Default to 0.
+    private int mHttpStatusCode = 0;
+
+    // Caches the http status text. Default to null.
+    private String mHttpStatusText;
+
+    // Caches the native error code. Default to no error.
+    private int mErrorCode = ChromiumUrlRequestError.SUCCESS;
+
+    // Caches the native error string. Default to null.
+    private String mErrorString;
+
     private final Object mLock = new Object();
 
     public ChromiumUrlRequest(ChromiumUrlRequestContext requestContext,
             String url, int priority, Map<String, String> headers,
             HttpUrlRequestListener listener) {
         this(requestContext, url, priority, headers,
                 new ChunkedWritableByteChannel(), listener);
         mBufferFullResponse = true;
     }
 
@@ skipping 49 matching lines @@
     }
 
     @Override
     public void setContentLengthLimit(long limit, boolean cancelEarly) {
         mContentLengthLimit = limit;
         mCancelIfContentLengthOverLimit = cancelEarly;
     }
 
     @Override
     public int getHttpStatusCode() {
-        int httpStatusCode = nativeGetHttpStatusCode(mUrlRequestAdapter);
+        if (mUrlRequestAdapter != 0) {
+            mHttpStatusCode = nativeGetHttpStatusCode(mUrlRequestAdapter);

[mmenke, 2015/02/25 23:43:57]

Can we populate this in onResponseStarted unconditionally instead?

[miloslav, 2015/02/26 15:56:49]

+1 for setting in onResponseStarted.

[xunjieli, 2015/02/26 17:54:00]

Done. Good idea! thanks!

[xunjieli, 2015/02/26 17:54:00]

Done.

+        }
 
         // TODO(mef): Investigate the following:
         // If we have been able to successfully resume a previously interrupted
         // download, the status code will be 206, not 200. Since the rest of the
         // application is expecting 200 to indicate success, we need to fake it.
-        if (httpStatusCode == 206) {
-            httpStatusCode = 200;
+        if (mHttpStatusCode == 206) {
+            mHttpStatusCode = 200;
         }
-        return httpStatusCode;
+        return mHttpStatusCode;
     }
 
     @Override
     public String getHttpStatusText() {

[miloslav, 2015/02/26 15:56:49]

As above. Also, it would be nice if you change the javadoc of
HttpUrlRequest#getHttpStatusCode to mention that it may return null the request
has not started.

[xunjieli, 2015/02/26 17:54:00]

Done.

-        return nativeGetHttpStatusText(mUrlRequestAdapter);
+        if (mUrlRequestAdapter != 0) {
+            mHttpStatusText = nativeGetHttpStatusText(mUrlRequestAdapter);
+        }
+        return mHttpStatusText;
     }
 
     /**
      * Returns an exception if any, or null if the request was completed
      * successfully.
      */
     @Override
     public IOException getException() {
         if (mSinkException != null) {
             return mSinkException;
         }
 
         validateNotRecycled();
 
-        int errorCode = nativeGetErrorCode(mUrlRequestAdapter);
-        switch (errorCode) {
+        if (mUrlRequestAdapter != 0) {
+            mErrorCode = nativeGetErrorCode(mUrlRequestAdapter);

[mmenke, 2015/02/25 23:43:57]

Can we populate this and mErrorString in whatever callback from net/ we normally
get on failures?  (OnRequestFinished?).  Then we don't need the
validateNotRecycled, either...  Also, currently, the validateNotRecycled means
we'll actually throw an exception if the adapter is 0 before we get to this
line.

[mmenke, 2015/02/25 23:45:37]

Also, if we care about this case, seems a problem that it wasn't caught by tests
(Which I haven't looked at / thought about yet)

[xunjieli, 2015/02/26 17:54:00]

Acknowledged.

[xunjieli, 2015/02/26 17:54:00]

Done. Thanks for clarifying about validateNotRecycled.

+        }
+
+        switch (mErrorCode) {
             case ChromiumUrlRequestError.SUCCESS:
                 if (mContentLengthOverLimit) {
                     return new ResponseTooLargeException();
                 }
                 return null;
             case ChromiumUrlRequestError.UNKNOWN:
-                return new IOException(
-                        nativeGetErrorString(mUrlRequestAdapter));
+                if (mUrlRequestAdapter != 0) {
+                    mErrorString = nativeGetErrorString(mUrlRequestAdapter);
+                }
+                return new IOException(mErrorString);
             case ChromiumUrlRequestError.MALFORMED_URL:
                 return new MalformedURLException("Malformed URL: " + mUrl);
             case ChromiumUrlRequestError.CONNECTION_TIMED_OUT:
                 return new ConnectTimeoutException("Connection timed out");
             case ChromiumUrlRequestError.UNKNOWN_HOST:
                 String host;
                 try {
                     host = new URL(mUrl).getHost();
                 } catch (MalformedURLException e) {
                     host = mUrl;
                 }
                 return new UnknownHostException("Unknown host: " + host);
             case ChromiumUrlRequestError.TOO_MANY_REDIRECTS:
                 return new IOException("Request failed because there were too "
                         + "many redirects or redirects have been disabled");
             default:
                 throw new IllegalStateException(
-                        "Unrecognized error code: " + errorCode);
+                        "Unrecognized error code: " + mErrorCode);
         }
     }
 
     @Override
     public ByteBuffer getByteBuffer() {
         return ((ChunkedWritableByteChannel) getSink()).getByteBuffer();
     }
 
     @Override
     public byte[] getResponseAsBytes() {
@@ skipping 518 matching lines @@
     private native void nativeGetAllHeaders(long urlRequestAdapter,
             ResponseHeadersMap headers);
 
     private native String nativeGetNegotiatedProtocol(long urlRequestAdapter);
 
     // Explicit class to work around JNI-generator generics confusion.
     private static class ResponseHeadersMap extends
             HashMap<String, List<String>> {
     }
 }