Upstreaming AndroidProtocolAdapter.

chrome/browser/android/android_protocol_adapter.cc

+// 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.
+
+// URL request job for reading data from an Android Java InputStream.
+
+#include "chrome/browser/android/android_protocol_adapter.h"
+
+#include "base/android/jni_android.h"
+#include "base/android/jni_helper.h"
+#include "base/android/jni_string.h"
+#include "chrome/browser/android/android_stream_reader_url_request_job.h"
+#include "content/public/common/url_constants.h"
+#include "googleurl/src/gurl.h"
+#include "net/base/io_buffer.h"
+#include "net/base/mime_util.h"
+#include "net/base/net_errors.h"
+#include "net/base/net_util.h"
+#include "net/http/http_util.h"
+#include "net/url_request/url_request.h"
+#include "net/url_request/url_request_error_job.h"
+#include "net/url_request/url_request_file_job.h"
+#include "net/url_request/url_request_job_manager.h"
+#include "jni/AndroidProtocolAdapter_jni.h"
+
+using base::android::AttachCurrentThread;
+using base::android::ClearException;
+using base::android::ConvertUTF8ToJavaString;
+using base::android::ScopedJavaGlobalRef;
+using base::android::ScopedJavaLocalRef;
+
+namespace {
+
+// Override resource context for reading resource and asset files. Used for
+// testing.
+JavaObjectWeakGlobalRef* g_resource_context = NULL;
+
+void ResetResourceContext(JavaObjectWeakGlobalRef* ref) {
+  if (g_resource_context)
+    delete g_resource_context;
+
+  g_resource_context = ref;
+}
+
+class AndroidStreamReaderURLRequestJobDelegateImpl :
+    public AndroidStreamReaderURLRequestJob::Delegate {
+ public:
+  AndroidStreamReaderURLRequestJobDelegateImpl();
+
+  virtual ScopedJavaLocalRef<jobject> OpenInputStream(
+      JNIEnv* env,
+      net::URLRequest* request) OVERRIDE;
+
+  virtual bool GetMimeType(JNIEnv* env,
+                           net::URLRequest* request,
+                           jobject stream,
+                           std::string* mime_type) OVERRIDE;
+
+  virtual bool GetCharset(JNIEnv* env,
+                          net::URLRequest* request,
+                          jobject stream,
+                          std::string* charset) OVERRIDE;
+
+  virtual ~AndroidStreamReaderURLRequestJobDelegateImpl();
+};
+
+
+} // namespace
+
+static bool InitJNIBindings(JNIEnv* env) {
+  return RegisterNativesImpl(env) &&
+      AndroidStreamReaderURLRequestJob::InitJNIBindings(env);
+}
+
+// static
+net::URLRequestJob* AndroidProtocolAdapter::Factory(
+    net::URLRequest* request, const std::string& scheme) {
+  DCHECK(scheme == chrome::kFileScheme ||
+         scheme == content::kContentScheme);
+  JNIEnv* env = AttachCurrentThread();
+  DCHECK(env);
+  // If this is a file:// URL we cannot handle, fall back to the default
+  // handler.
+  const std::string& url = request->url().spec();
+  std::string assetPrefix = std::string(chrome::kFileScheme) + "://" +
+      content::kAndroidAssetPath;
+  std::string resourcePrefix = std::string(chrome::kFileScheme) + "://" +
+      content::kAndroidResourcePath;
+  if (scheme == chrome::kFileScheme && url.find(assetPrefix) != 0 &&
+      url.find(resourcePrefix) != 0) {
+    return net::URLRequestFileJob::Factory(request, scheme);
+  }
+
+  return new AndroidStreamReaderURLRequestJob(
+      request,
+      scoped_ptr<AndroidStreamReaderURLRequestJob::Delegate>(
+          new AndroidStreamReaderURLRequestJobDelegateImpl()));
+}
+
+// static
+bool AndroidProtocolAdapter::RegisterProtocols(JNIEnv* env) {
+  DCHECK(env);
+
+  if (!InitJNIBindings(env))
+    return false;
+
+  // Register content:// and file://. Note that even though a scheme is
+  // registered here, it cannot be used by child processes until access to it is
+  // granted via ChildProcessSecurityPolicy::GrantScheme(). This is done in
+  // RenderViewHost.
+  net::URLRequestJobManager* job_manager =
+      net::URLRequestJobManager::GetInstance();
+  job_manager->RegisterProtocolFactory(content::kContentScheme,
+      &AndroidProtocolAdapter::Factory);
+  job_manager->RegisterProtocolFactory(
+      chrome::kFileScheme, &AndroidProtocolAdapter::Factory);
+
+  return true;
+}
+
+// Set a context object to be used for resolving resource queries. This can
+// be used to override the default application context and redirect all
+// resource queries to a specific context object, e.g., for the purposes of
+// testing.
+//
+// |context| should be a android.content.Context instance or NULL to enable
+// the use of the standard application context.
+static void SetResourceContext(JNIEnv* env, jclass /*clazz*/, jobject context) {
+  if (context) {
+    ResetResourceContext(new JavaObjectWeakGlobalRef(env, context));
+  } else {
+    ResetResourceContext(NULL);
+  }
+}
+
+static jstring GetAndroidAssetPath(JNIEnv* env, jclass /*clazz*/) {
+  // OK to release, JNI binding.
+  return ConvertUTF8ToJavaString(env, content::kAndroidAssetPath).Release();
+}
+
+static jstring GetAndroidResourcePath(JNIEnv* env, jclass /*clazz*/) {
+  // OK to release, JNI binding.
+  return ConvertUTF8ToJavaString(env, content::kAndroidResourcePath).Release();
+}
+
+static ScopedJavaLocalRef<jobject> GetResourceContext(JNIEnv* env) {
+  if (g_resource_context)
+    return g_resource_context->get(env);
+  ScopedJavaLocalRef<jobject> context;
+  //  We have to reset as GetApplicationContext() returns a jobject with a
+  // global ref. The constructor that takes a jobject would expect a local ref
+  // and would assert.
+  context.Reset(env, base::android::GetApplicationContext());
+  return context;
+}
+
+AndroidStreamReaderURLRequestJobDelegateImpl::
+AndroidStreamReaderURLRequestJobDelegateImpl() {
+}
+
+AndroidStreamReaderURLRequestJobDelegateImpl::
+~AndroidStreamReaderURLRequestJobDelegateImpl() {
+}
+
+ScopedJavaLocalRef<jobject>
+AndroidStreamReaderURLRequestJobDelegateImpl::OpenInputStream(
+    JNIEnv* env, net::URLRequest* request) {
+  DCHECK(request);
+  DCHECK(env);
+
+  // Open the input stream.
+  ScopedJavaLocalRef<jstring> url =
+      ConvertUTF8ToJavaString(env, request->url().spec());
+  ScopedJavaLocalRef<jobject> stream = Java_AndroidProtocolAdapter_open(
+      env,
+      GetResourceContext(env).obj(),
+      url.obj());
+
+  // Check and clear pending exceptions.
+  if (ClearException(env) || stream.is_null()) {
+    DLOG(ERROR) << "Unable to open input stream for Android URL";
+    return ScopedJavaLocalRef<jobject>(env, NULL);
+  }
+  return stream;
+}
+
+bool AndroidStreamReaderURLRequestJobDelegateImpl::GetMimeType(
+    JNIEnv* env,
+    net::URLRequest* request,
+    jobject stream,
+    std::string* mime_type) {
+  DCHECK(env);
+  DCHECK(request);
+  DCHECK(mime_type);
+
+  if (!stream)
+    return false;
+
+  // Query the mime type from the Java side. It is possible for the query to
+  // fail, as the mime type cannot be determined for all supported schemes.
+  ScopedJavaLocalRef<jstring> url =
+      ConvertUTF8ToJavaString(env, request->url().spec());
+  ScopedJavaLocalRef<jstring> returned_type =
+      Java_AndroidProtocolAdapter_getMimeType(env,
+                                              GetResourceContext(env).obj(),
+                                              stream, url.obj());
+  if (ClearException(env) || returned_type.is_null())
+    return false;
+
+  *mime_type = base::android::ConvertJavaStringToUTF8(returned_type);
+  return true;
+}
+
+bool AndroidStreamReaderURLRequestJobDelegateImpl::GetCharset(
+    JNIEnv* env,
+    net::URLRequest* request,
+    jobject stream,
+    std::string* charset) {
+  // TODO: We should probably be getting this from the managed side.
+  return false;
+}