From f58215f418b2ec822b289237228d60b8cc070ed9 Mon Sep 17 00:00:00 2001
From: Chris Manton <cmanton@google.com>
Date: Sat, 26 Sep 2020 16:07:41 -0700
Subject: [PATCH] Single out Register events LE_META_EVENT as special

LE_META_EVENT is a special event that multiplexes LE
events underneath and should not be exposed.

Test Parameters: INIT_gd_hci=true

Bug: 166280067
Tag: #refactor
Test: gd/cert/run --host
Test: ble paired 2 phones
Test: act.py -tc BleCocTest
Change-Id: Idf8dd9fa9e13fc9e2d1d7d89d6af0a16ec574b89
---
 gd/hci/hci_layer.cc | 40 +++++++++++++++++++++++++++++++++-------
 gd/hci/hci_layer.h  |  1 +
 2 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/gd/hci/hci_layer.cc b/gd/hci/hci_layer.cc
index e581f2436..c480fc1d7 100644
--- a/gd/hci/hci_layer.cc
+++ b/gd/hci/hci_layer.cc
@@ -171,6 +171,11 @@ struct HciLayer::impl {
   }
 
   void register_event(EventCode event, ContextualCallback<void(EventPacketView)> handler) {
+    ASSERT_LOG(
+        event != EventCode::LE_META_EVENT,
+        "Can not register handler for %02hhx (%s)",
+        EventCode::LE_META_EVENT,
+        EventCodeText(EventCode::LE_META_EVENT).c_str());
     ASSERT_LOG(event_handlers_.count(event) == 0, "Can not register a second handler for %02hhx (%s)", event,
                EventCodeText(event).c_str());
     event_handlers_[event] = handler;
@@ -180,6 +185,19 @@ struct HciLayer::impl {
     event_handlers_.erase(event_handlers_.find(event));
   }
 
+  void register_le_meta_event(ContextualCallback<void(EventPacketView)> handler) {
+    ASSERT_LOG(
+        event_handlers_.count(EventCode::LE_META_EVENT) == 0,
+        "Can not register a second handler for %02hhx (%s)",
+        EventCode::LE_META_EVENT,
+        EventCodeText(EventCode::LE_META_EVENT).c_str());
+    event_handlers_[EventCode::LE_META_EVENT] = handler;
+  }
+
+  void unregister_le_meta_event() {
+    unregister_event(EventCode::LE_META_EVENT);
+  }
+
   void register_le_event(SubeventCode event, ContextualCallback<void(LeMetaEventView)> handler) {
     ASSERT_LOG(subevent_handlers_.count(event) == 0, "Can not register a second handler for %02hhx (%s)", event,
                SubeventCodeText(event).c_str());
@@ -193,10 +211,11 @@ struct HciLayer::impl {
   void on_hci_event(EventPacketView event) {
     ASSERT(event.IsValid());
     EventCode event_code = event.GetEventCode();
-    if (event_handlers_.find(event_code) == event_handlers_.end()) {
-      LOG_DEBUG("Dropping unregistered event of type 0x%02hhx (%s)", event_code, EventCodeText(event_code).c_str());
-      return;
-    }
+    ASSERT_LOG(
+        event_handlers_.find(event_code) != event_handlers_.end(),
+        "Unhandled event of type 0x%02hhx (%s)",
+        event_code,
+        EventCodeText(event_code).c_str());
     event_handlers_[event_code].Invoke(event);
   }
 
@@ -204,8 +223,11 @@ struct HciLayer::impl {
     LeMetaEventView meta_event_view = LeMetaEventView::Create(event);
     ASSERT(meta_event_view.IsValid());
     SubeventCode subevent_code = meta_event_view.GetSubeventCode();
-    ASSERT_LOG(subevent_handlers_.find(subevent_code) != subevent_handlers_.end(),
-               "Unhandled le event of type 0x%02hhx (%s)", subevent_code, SubeventCodeText(subevent_code).c_str());
+    ASSERT_LOG(
+        subevent_handlers_.find(subevent_code) != subevent_handlers_.end(),
+        "Unhandled le subevent of type 0x%02hhx (%s)",
+        subevent_code,
+        SubeventCodeText(subevent_code).c_str());
     subevent_handlers_[subevent_code].Invoke(meta_event_view);
   }
 
@@ -276,6 +298,10 @@ void HciLayer::RegisterEventHandler(EventCode event, ContextualCallback<void(Eve
   CallOn(impl_, &impl::register_event, event, handler);
 }
 
+void HciLayer::RegisterLeMetaEventHandler(ContextualCallback<void(EventPacketView)> handler) {
+  CallOn(impl_, &impl::register_le_meta_event, handler);
+}
+
 void HciLayer::UnregisterEventHandler(EventCode event) {
   CallOn(impl_, &impl::unregister_event, event);
 }
@@ -369,8 +395,8 @@ void HciLayer::Start() {
   impl_->acl_queue_.GetDownEnd()->RegisterDequeue(handler, BindOn(impl_, &impl::on_outbound_acl_ready));
   RegisterEventHandler(EventCode::COMMAND_COMPLETE, handler->BindOn(impl_, &impl::on_command_complete));
   RegisterEventHandler(EventCode::COMMAND_STATUS, handler->BindOn(impl_, &impl::on_command_status));
+  RegisterLeMetaEventHandler(handler->BindOn(impl_, &impl::on_le_meta_event));
   if (bluetooth::common::InitFlags::GdCoreEnabled()) {
-    RegisterEventHandler(EventCode::LE_META_EVENT, handler->BindOn(impl_, &impl::on_le_meta_event));
     RegisterEventHandler(
         EventCode::DISCONNECTION_COMPLETE, handler->BindOn(this, &HciLayer::on_disconnection_complete));
   }
diff --git a/gd/hci/hci_layer.h b/gd/hci/hci_layer.h
index 812340505..da3335b65 100644
--- a/gd/hci/hci_layer.h
+++ b/gd/hci/hci_layer.h
@@ -97,6 +97,7 @@ class HciLayer : public Module, public CommandInterface<CommandPacketBuilder> {
   void Stop() override;
 
   virtual void Disconnect(uint16_t handle, ErrorCode reason);
+  virtual void RegisterLeMetaEventHandler(common::ContextualCallback<void(EventPacketView)> event_handler);
 
  private:
   struct impl;
-- 
2.11.0