[android_webview] Don't block the IO thread when reading from an InputStream.

android_webview/native/android_stream_reader_url_request_job.h

 // Copyright (c) 2012 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.
 
 #ifndef ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
 #define ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
 
 #include "base/android/scoped_java_ref.h"
+#include "base/location.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "net/http/http_byte_range.h"
 #include "net/url_request/url_request_job.h"
 
+namespace android_webview {
+class InputStream;
+class InputStreamReader;
+}
+
 namespace net {
 class URLRequest;
 }
 
 // A request job that reads data from a Java InputStream.
 class AndroidStreamReaderURLRequestJob : public net::URLRequestJob {
  public:
   /*
    * We use a delegate so that we can share code for this job in slightly
    * different contexts.
    */
   class Delegate {
    public:
-    virtual base::android::ScopedJavaLocalRef<jobject> OpenInputStream(
+    virtual scoped_ptr<android_webview::InputStream> OpenInputStream(
         JNIEnv* env,
         net::URLRequest* request) = 0;
 
     virtual bool GetMimeType(
         JNIEnv* env,
         net::URLRequest* request,
-        jobject stream,
+        const android_webview::InputStream& stream,
         std::string* mime_type) = 0;
 
     virtual bool GetCharset(
         JNIEnv* env,
         net::URLRequest* request,
-        jobject stream,
+        const android_webview::InputStream& stream,
         std::string* charset) = 0;
 
     virtual ~Delegate() {}
   };
 
   AndroidStreamReaderURLRequestJob(
       net::URLRequest* request,
       net::NetworkDelegate* network_delegate,
       scoped_ptr<Delegate> delegate);
 
   // URLRequestJob:
   virtual void Start() OVERRIDE;
+  virtual void Kill() OVERRIDE;
   virtual bool ReadRawData(net::IOBuffer* buf,
                            int buf_size,
                            int* bytes_read) OVERRIDE;
   virtual void SetExtraRequestHeaders(
       const net::HttpRequestHeaders& headers) OVERRIDE;
   virtual bool GetMimeType(std::string* mime_type) const OVERRIDE;
   virtual bool GetCharset(std::string* charset) OVERRIDE;
 
  protected:
   virtual ~AndroidStreamReaderURLRequestJob();
 
+  // Posts the |task| to the background worker thread.
+  // Useful to override in tests.
+  virtual void PostToWorkerThread(const tracked_objects::Location& from_here,
+                                  const base::Closure& task);
+
+  // Creates an InputStreamReader instance.
+  virtual android_webview::InputStreamReader*
+      CreateStreamReader(android_webview::InputStream* stream);
+
  private:
-  // Verify the requested range against the stream size.
-  bool VerifyRequestedRange(JNIEnv* env);
+  void StartAsync();
 
-  // Skip to the first byte of the requested read range.
-  bool SkipToRequestedRange(JNIEnv* env);
-
-  void StartAsync();
+  void OnReaderSeekCompleted(int content_size);
+  void OnReaderReadCompleted(int bytes_read);
 
   net::HttpByteRange byte_range_;
   scoped_ptr<Delegate> delegate_;
-  base::android::ScopedJavaGlobalRef<jobject> stream_;
-  base::android::ScopedJavaGlobalRef<jbyteArray> buffer_;
+  android_webview::InputStreamReader* input_stream_reader_;
+  scoped_ptr<android_webview::InputStream> stream_;
   base::WeakPtrFactory<AndroidStreamReaderURLRequestJob> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AndroidStreamReaderURLRequestJob);
 };
 
-bool RegisterAndroidStreamReaderUrlRequestJob(JNIEnv* env);
-
 #endif  // ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_