Web restrictions component only.

components/web_restriction/content_resolver_web_restriction_provider.cc

+// Copyright 2015 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.
+
+#include "components/web_restriction/content_resolver_web_restriction_provider.h"
+
+#include "base/android/jni_string.h"
+#include "base/android/scoped_java_ref.h"
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/thread_task_runner_handle.h"
+#include "jni/ContentResolverWebRestrictionProvider_jni.h"
+
+namespace {
+const size_t kMaxCacheSize = 100;
+}  // namespace
+
+namespace web_restriction {
+namespace android {
+
+SelfDeletingCallback::SelfDeletingCallback(
+    const GURL& url,
+    const base::Callback<void(bool)>& callback,
+    const scoped_refptr<base::TaskRunner>& callback_runner,
+    ContentResolverWebRestrictionProvider* provider)
+    : url_(url),
+      callback_(callback),
+      callback_runner_(callback_runner),
+      provider_(provider) {}
+
+SelfDeletingCallback::~SelfDeletingCallback() {}
+
+void SelfDeletingCallback::ShouldProceed(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj,
+    jboolean should_proceed,
+    const base::android::JavaParamRef<jstring>& j_error_page) {
+  auto& url_access_cache = provider_->url_access_cache_;
+  auto& error_page_cache = provider_->error_page_cache_;
+  auto& recent_urls = provider_->recent_urls_;
+  url_access_cache.erase(url_);
+  error_page_cache.erase(url_);
+  recent_urls.remove(url_);
+  if (recent_urls.size() >= kMaxCacheSize) {
+    url_access_cache.erase(recent_urls.back());
+    error_page_cache.erase(recent_urls.back());
+    recent_urls.pop_back();
+  }
+  recent_urls.push_front(url_);
+  url_access_cache[url_] = should_proceed;
+  if (!j_error_page.is_null()) {
+    error_page_cache[url_] =
+        base::android::ConvertJavaStringToUTF8(j_error_page);
+  }
+  callback_runner_->PostTask(FROM_HERE, base::Bind(callback_, should_proceed));
+  delete this;
+}

[Bernhard Bauer, 2016/01/26 11:09:02]

Empty line afterwards

[knn, 2016/01/26 14:37:43]

Done.

+void SelfDeletingCallback::RequestSuccess(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj,
+    jboolean request_success) {
+  callback_runner_->PostTask(FROM_HERE, base::Bind(callback_, request_success));
+  delete this;
+}
+
+}  // namespace android
+
+// static
+bool ContentResolverWebRestrictionProvider::Register(JNIEnv* env) {
+  return android::RegisterNativesImpl(env);
+}
+
+ContentResolverWebRestrictionProvider::ContentResolverWebRestrictionProvider() {
+  initialized_ = false;

[Bernhard Bauer, 2016/01/26 11:09:02]

You can do this as part of the initializer list (`initialized_(false)`).

[knn, 2016/01/26 14:37:43]

Done.

+}
+
+ContentResolverWebRestrictionProvider::
+    ~ContentResolverWebRestrictionProvider() {}
+
+void ContentResolverWebRestrictionProvider::Initialize(
+    const std::string& content_provider_authority) {

[Bernhard Bauer, 2016/01/27 14:24:00]

Could you also DCHECK(!initialized_)?

[knn, 2016/01/28 11:43:25]

I was thinking, this may be re-initialized with a new provider if the policy
ever changes.

[Bernhard Bauer, 2016/01/28 12:15:14]

That makes sense, but maybe add a comment that explicitly explains that we allow
multiple initialization? Or actually, just call it SetAuthority()?

+  DCHECK(!content_provider_authority.empty());
+  JNIEnv* env = base::android::AttachCurrentThread();
+  java_provider_.Reset(
+      android::Java_ContentResolverWebRestrictionProvider_create(
+          env, base::android::ConvertUTF8ToJavaString(
+                   env, content_provider_authority)
+                   .obj()));
+  supports_request_ =
+      android::Java_ContentResolverWebRestrictionProvider_supportsRequest(
+          env, java_provider_.obj());
+  error_page_cache_.clear();

[Bernhard Bauer, 2016/01/27 14:24:01]

You could just DCHECK that these are empty, right?

[knn, 2016/01/28 11:43:25]

See above. (provider change)

+  url_access_cache_.clear();
+  recent_urls_.clear();
+  initialized_ = true;
+}
+
+UrlAccess ContentResolverWebRestrictionProvider::ShouldProceed(
+    bool is_main_frame,
+    const GURL& url,
+    const base::Callback<void(bool)>& callback) {
+  if (!initialized_)
+    return ALLOW;

[Bernhard Bauer, 2016/01/27 14:24:00]

When would this actually happen?

[knn, 2016/01/28 11:43:25]

If the policy is not set, we won't initialize it.

+  auto iter = url_access_cache_.find(url);
+  if (iter != url_access_cache_.end()) {
+    // Move the url to the front of the cache.
+    recent_urls_.remove(url);
+    recent_urls_.push_front(url);
+    return iter->second ? ALLOW : DISALLOW;
+  }
+  scoped_refptr<base::SingleThreadTaskRunner> callback_runner =
+      base::ThreadTaskRunnerHandle::Get();
+  android::SelfDeletingCallback* wrapped_callback =
+      new android::SelfDeletingCallback(url, callback, callback_runner, this);
+  JNIEnv* env = base::android::AttachCurrentThread();
+  android::Java_ContentResolverWebRestrictionProvider_shouldProceed(
+      env, java_provider_.obj(), reinterpret_cast<jlong>(wrapped_callback),
+      base::android::ConvertUTF8ToJavaString(env, url.spec()).obj());
+  return PENDING;
+}
+
+bool ContentResolverWebRestrictionProvider::SupportsRequest() const {
+  return initialized_ && supports_request_;
+}
+
+bool ContentResolverWebRestrictionProvider::GetErrorHtml(
+    const GURL& url,
+    std::string* error_page) const {
+  if (!initialized_)
+    return false;
+  auto iter = error_page_cache_.find(url);
+  if (iter == error_page_cache_.end())
+    return false;
+  *error_page = iter->second;
+  return true;
+}
+
+void ContentResolverWebRestrictionProvider::RequestPermission(
+    const GURL& url,
+    const base::Callback<void(bool)>& request_success) {
+  if (!initialized_) {
+    request_success.Run(false);
+    return;
+  }
+  scoped_refptr<base::SingleThreadTaskRunner> callback_runner =
+      base::ThreadTaskRunnerHandle::Get();
+  android::SelfDeletingCallback* wrapped_callback =
+      new android::SelfDeletingCallback(url, request_success, callback_runner,
+                                        this);
+  JNIEnv* env = base::android::AttachCurrentThread();
+  android::Java_ContentResolverWebRestrictionProvider_requestPermission(
+      env, java_provider_.obj(), reinterpret_cast<jlong>(wrapped_callback),
+      base::android::ConvertUTF8ToJavaString(env, url.spec()).obj());
+}
+
+}  // namespace web_restriction