Change ProxyResolver::GetProxyForURL() to take a scoped_ptr<Request>* rather than a RequestHandle*

net/proxy/proxy_resolver_v8_tracing.cc

 // Copyright (c) 2013 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 "net/proxy/proxy_resolver_v8_tracing.h"
 
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 57 matching lines @@
 // seems to be misbehaving under the tracing optimization.
 //
 // Note that this class runs on both the origin thread and a worker
 // thread. Most methods are expected to be used exclusively on one thread
 // or the other.
 //
 // The lifetime of Jobs does not exceed that of the ProxyResolverV8TracingImpl
 // that spawned it. Destruction might happen on either the origin thread or the
 // worker thread.
 class Job : public base::RefCountedThreadSafe<Job>,
+            public base::SupportsWeakPtr<Job>,
             public ProxyResolverV8::JSBindings {
  public:
   struct Params {
     Params(
         const scoped_refptr<base::SingleThreadTaskRunner>& worker_task_runner,
         int* num_outstanding_callbacks)
         : v8_resolver(nullptr),
           worker_task_runner(worker_task_runner),
           num_outstanding_callbacks(num_outstanding_callbacks) {}
 
@@ skipping 216 matching lines @@
   ProxyResolverV8TracingImpl(scoped_ptr<base::Thread> thread,
                              scoped_ptr<ProxyResolverV8> resolver,
                              scoped_ptr<Job::Params> job_params);
 
   ~ProxyResolverV8TracingImpl() override;
 
   // ProxyResolverV8Tracing overrides.
   void GetProxyForURL(const GURL& url,
                       ProxyInfo* results,
                       const CompletionCallback& callback,
-                      ProxyResolver::RequestHandle* request,
+                      scoped_ptr<ProxyResolver::Request>* request,
                       scoped_ptr<Bindings> bindings) override;
-  void CancelRequest(ProxyResolver::RequestHandle request) override;
-  LoadState GetLoadState(ProxyResolver::RequestHandle request) const override;
+
+  class RequestImpl : public ProxyResolverV8Tracing::Request {
+   public:
+    RequestImpl(base::WeakPtr<Job> job);
+    ~RequestImpl() override;
+    LoadState GetLoadState() override;
+
+   private:
+    base::WeakPtr<Job> job_;
+  };
 
  private:
   // The worker thread on which the ProxyResolverV8 will be run.
   scoped_ptr<base::Thread> thread_;
   scoped_ptr<ProxyResolverV8> v8_resolver_;
 
   scoped_ptr<Job::Params> job_params_;
 
   // The number of outstanding (non-cancelled) jobs.
   int num_outstanding_callbacks_;
@@ skipping 99 matching lines @@
 }
 
 void Job::SetCallback(const CompletionCallback& callback) {
   CheckIsOnOriginThread();
   DCHECK(callback_.is_null());
   (*params_->num_outstanding_callbacks)++;
   callback_ = callback;
 }
 
 void Job::ReleaseCallback() {
+  if (callback_.is_null())
+    return;
   CheckIsOnOriginThread();
   DCHECK(!callback_.is_null());
   CHECK_GT(*params_->num_outstanding_callbacks, 0);
   (*params_->num_outstanding_callbacks)--;
   callback_.Reset();
 
   // For good measure, clear this other user-owned pointer.
   user_results_ = NULL;
 }
 
@@ skipping 480 matching lines @@
 
 ProxyResolverV8TracingImpl::~ProxyResolverV8TracingImpl() {
   // Note, all requests should have been cancelled.
   CHECK_EQ(0, num_outstanding_callbacks_);
 
   // Join the worker thread. See http://crbug.com/69710.
   base::ThreadRestrictions::ScopedAllowIO allow_io;
   thread_.reset();
 }
 
+ProxyResolverV8TracingImpl::RequestImpl::RequestImpl(base::WeakPtr<Job> job)
+    : job_(job) {}

[eroman, 2016/01/23 02:17:01]

Same comment as for MultiThreadedProxyResolver. I don't think we want a weak
pointer here, can instead hold a strong reference.

+
+ProxyResolverV8TracingImpl::RequestImpl::~RequestImpl() {
+  if (job_)

[eroman, 2016/01/23 02:17:01]

Shouldn't need this check once making job_ a strong reference.

+    job_->Cancel();
+}
+
+LoadState ProxyResolverV8TracingImpl::RequestImpl::GetLoadState() {
+  return job_->GetLoadState();
+}
+
 void ProxyResolverV8TracingImpl::GetProxyForURL(
     const GURL& url,
     ProxyInfo* results,
     const CompletionCallback& callback,
-    ProxyResolver::RequestHandle* request,
+    scoped_ptr<ProxyResolver::Request>* request,
     scoped_ptr<Bindings> bindings) {
   DCHECK(CalledOnValidThread());
   DCHECK(!callback.is_null());
 
   scoped_refptr<Job> job = new Job(job_params_.get(), std::move(bindings));
 
   if (request)

[eroman, 2016/01/23 02:17:01]

I wonder if we actually use this check (should at some mandate that |request !=
nullptr|.
Shouldn't matter for this CL though since the Job is kept alive by the executor
already.

-    *request = job.get();
+    request->reset(new RequestImpl(job->AsWeakPtr()));
 
   job->StartGetProxyForURL(url, results, callback);
 }
 
-void ProxyResolverV8TracingImpl::CancelRequest(
-    ProxyResolver::RequestHandle request) {
-  Job* job = reinterpret_cast<Job*>(request);
-  job->Cancel();
-}
-
-LoadState ProxyResolverV8TracingImpl::GetLoadState(
-    ProxyResolver::RequestHandle request) const {
-  Job* job = reinterpret_cast<Job*>(request);
-  return job->GetLoadState();
-}
 
 class ProxyResolverV8TracingFactoryImpl : public ProxyResolverV8TracingFactory {
  public:
   ProxyResolverV8TracingFactoryImpl();
   ~ProxyResolverV8TracingFactoryImpl() override;
 
   void CreateProxyResolverV8Tracing(
       const scoped_refptr<ProxyResolverScriptData>& pac_script,
       scoped_ptr<ProxyResolverV8Tracing::Bindings> bindings,
       scoped_ptr<ProxyResolverV8Tracing>* resolver,
@@ skipping 118 matching lines @@
 
 }  // namespace
 
 // static
 scoped_ptr<ProxyResolverV8TracingFactory>
 ProxyResolverV8TracingFactory::Create() {
   return make_scoped_ptr(new ProxyResolverV8TracingFactoryImpl());
 }
 
 }  // namespace net