Complete SyncMessageFilter initialization after SyncChannel initialization

This changes SyncChannel to keep track of any SyncMessageFilters it
creates prior to ChannelProxy::Init being called. Once Init completes,
initialization of all tracked SyncMessageFilters is completed by
updating their is_channel_send_thread_safe flag.

BUG=516464
R=jam@chromium.org

Review URL: https://codereview.chromium.org/1279863004

Cr-Commit-Position: refs/heads/master@{#342308}

5 files changed, 32 insertions, 1 deletions

diff --git a/ipc/ipc_channel_proxy.cc b/ipc/ipc_channel_proxy.cc
index adb3d67..2398b51 100644
--- a/ipc/ipc_channel_proxy.cc
+++ b/ipc/ipc_channel_proxy.cc
@@ -430,6 +430,7 @@ void ChannelProxy::Init(scoped_ptr<ChannelFactory> factory,
       FROM_HERE, base::Bind(&Context::OnChannelOpened, context_.get()));
 
   did_init_ = true;
+  OnChannelInit();
 }
 
 void ChannelProxy::Close() {
@@ -514,6 +515,9 @@ void ChannelProxy::SetAttachmentBrokerEndpoint(bool is_endpoint) {
   context()->set_attachment_broker_endpoint(is_endpoint);
 }
 
+void ChannelProxy::OnChannelInit() {
+}
+
 //-----------------------------------------------------------------------------
 
 }  // namespace IPC
diff --git a/ipc/ipc_channel_proxy.h b/ipc/ipc_channel_proxy.h
index f9f7d31..b01ccbc 100644
--- a/ipc/ipc_channel_proxy.h
+++ b/ipc/ipc_channel_proxy.h
@@ -289,9 +289,15 @@ class IPC_EXPORT ChannelProxy : public Sender, public base::NonThreadSafe {
   }
 #endif
 
+ protected:
+  bool did_init() const { return did_init_; }
+
  private:
   friend class IpcSecurityTestUtil;
 
+  // Always called once immediately after Init.
+  virtual void OnChannelInit();
+
   // By maintaining this indirection (ref-counted) to our internal state, we
   // can safely be destroyed while the background thread continues to do stuff
   // that involves this data.
diff --git a/ipc/ipc_sync_channel.cc b/ipc/ipc_sync_channel.cc
index 845eccd..04ebd41 100644
--- a/ipc/ipc_sync_channel.cc
+++ b/ipc/ipc_sync_channel.cc
@@ -465,6 +465,8 @@ scoped_refptr<SyncMessageFilter> SyncChannel::CreateSyncMessageFilter() {
       sync_context()->shutdown_event(),
       sync_context()->IsChannelSendThreadSafe());
   AddFilter(filter.get());
+  if (!did_init())
+    pre_init_sync_message_filters_.push_back(filter);
   return filter;
 }
 
@@ -592,4 +594,12 @@ void SyncChannel::StartWatching() {
                                   dispatch_watcher_callback_);
 }
 
+void SyncChannel::OnChannelInit() {
+  for (const auto& filter : pre_init_sync_message_filters_) {
+    filter->set_is_channel_send_thread_safe(
+        context()->IsChannelSendThreadSafe());
+  }
+  pre_init_sync_message_filters_.clear();
+}
+
 }  // namespace IPC
diff --git a/ipc/ipc_sync_channel.h b/ipc/ipc_sync_channel.h
index 2fd1b11..243d6b0 100644
--- a/ipc/ipc_sync_channel.h
+++ b/ipc/ipc_sync_channel.h
@@ -5,8 +5,9 @@
 #ifndef IPC_IPC_SYNC_CHANNEL_H_
 #define IPC_IPC_SYNC_CHANNEL_H_
 
-#include <string>
 #include <deque>
+#include <string>
+#include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
@@ -233,10 +234,16 @@ class IPC_EXPORT SyncChannel : public ChannelProxy {
   // Starts the dispatch watcher.
   void StartWatching();
 
+  // ChannelProxy overrides:
+  void OnChannelInit() override;
+
   // Used to signal events between the IPC and listener threads.
   base::WaitableEventWatcher dispatch_watcher_;
   base::WaitableEventWatcher::EventCallback dispatch_watcher_callback_;
 
+  // Tracks SyncMessageFilters created before complete channel initialization.
+  std::vector<scoped_refptr<SyncMessageFilter>> pre_init_sync_message_filters_;
+
   DISALLOW_COPY_AND_ASSIGN(SyncChannel);
 };
 
diff --git a/ipc/ipc_sync_message_filter.h b/ipc/ipc_sync_message_filter.h
index 2a3c4e8..6e4f991 100644
--- a/ipc/ipc_sync_message_filter.h
+++ b/ipc/ipc_sync_message_filter.h
@@ -48,6 +48,10 @@ class IPC_EXPORT SyncMessageFilter : public MessageFilter, public Sender {
  private:
   friend class SyncChannel;
 
+  void set_is_channel_send_thread_safe(bool is_channel_send_thread_safe) {
+    is_channel_send_thread_safe_ = is_channel_send_thread_safe;
+  }
+
   void SendOnIOThread(Message* message);
   // Signal all the pending sends as done, used in an error condition.
   void SignalAllEvents();