1 files changed, 30 insertions, 340 deletions

diff --git a/mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.cc b/mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.cc
index c134507..f54c3f7 100644
--- a/mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.cc
+++ b/mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.cc
@@ -4,379 +4,69 @@
 
 #include "mojo/public/cpp/bindings/scoped_interface_endpoint_handle.h"
 
-#include "base/bind.h"
 #include "base/logging.h"
-#include "base/synchronization/lock.h"
 #include "mojo/public/cpp/bindings/associated_group_controller.h"
-#include "mojo/public/cpp/bindings/lib/may_auto_lock.h"
 
 namespace mojo {
 
-// ScopedInterfaceEndpointHandle::State ----------------------------------------
-
-// State could be called from multiple threads.
-class ScopedInterfaceEndpointHandle::State
-    : public base::RefCountedThreadSafe<State> {
- public:
-  State() = default;
-
-  State(InterfaceId id,
-        scoped_refptr<AssociatedGroupController> group_controller)
-      : id_(id), group_controller_(group_controller) {}
-
-  void InitPendingState(scoped_refptr<State> peer) {
-    DCHECK(!lock_);
-    DCHECK(!pending_association_);
-
-    lock_.emplace();
-    pending_association_ = true;
-    peer_state_ = std::move(peer);
-  }
-
-  void Close(const base::Optional<DisconnectReason>& reason) {
-    scoped_refptr<AssociatedGroupController> cached_group_controller;
-    InterfaceId cached_id = kInvalidInterfaceId;
-    scoped_refptr<State> cached_peer_state;
-
-    {
-      internal::MayAutoLock locker(&lock_);
-
-      if (!association_event_handler_.is_null()) {
-        association_event_handler_.Reset();
-        runner_ = nullptr;
-      }
-
-      if (!pending_association_) {
-        if (IsValidInterfaceId(id_)) {
-          // Intentionally keep |group_controller_| unchanged.
-          // That is because the callback created by
-          // CreateGroupControllerGetter() could still be used after this point,
-          // potentially from another thread. We would like it to continue
-          // returning the same group controller.
-          //
-          // Imagine there is a ThreadSafeForwarder A:
-          // (1) On the IO thread, A's underlying associated interface pointer
-          //     is closed.
-          // (2) On the proxy thread, the user makes a call on A to pass an
-          //     associated request B_asso_req. The callback returned by
-          //     CreateGroupControllerGetter() is used to associate B_asso_req.
-          // (3) On the proxy thread, the user immediately binds B_asso_ptr_info
-          //     to B_asso_ptr and makes calls on it.
-          //
-          // If we reset |group_controller_| in step (1), step (2) won't be able
-          // to associate B_asso_req. Therefore, in step (3) B_asso_ptr won't be
-          // able to serialize associated endpoints or send message because it
-          // is still in "pending_association" state and doesn't have a group
-          // controller.
-          //
-          // We could "address" this issue by ignoring messages if there isn't a
-          // group controller. But the side effect is that we cannot detect
-          // programming errors of "using associated interface pointer before
-          // sending associated request".
-
-          cached_group_controller = group_controller_;
-          cached_id = id_;
-          id_ = kInvalidInterfaceId;
-        }
-      } else {
-        pending_association_ = false;
-        cached_peer_state = std::move(peer_state_);
-      }
-    }
-
-    if (cached_group_controller) {
-      cached_group_controller->CloseEndpointHandle(cached_id, reason);
-    } else if (cached_peer_state) {
-      cached_peer_state->OnPeerClosedBeforeAssociation(reason);
-    }
-  }
-
-  void SetAssociationEventHandler(AssociationEventCallback handler) {
-    internal::MayAutoLock locker(&lock_);
-
-    if (!pending_association_ && !IsValidInterfaceId(id_))
-      return;
-
-    association_event_handler_ = std::move(handler);
-    if (association_event_handler_.is_null()) {
-      runner_ = nullptr;
-      return;
-    }
-
-    runner_ = base::ThreadTaskRunnerHandle::Get();
-    if (!pending_association_) {
-      runner_->PostTask(
-          FROM_HERE,
-          base::Bind(
-              &ScopedInterfaceEndpointHandle::State::RunAssociationEventHandler,
-              this, runner_, ASSOCIATED));
-    } else if (!peer_state_) {
-      runner_->PostTask(
-          FROM_HERE,
-          base::Bind(
-              &ScopedInterfaceEndpointHandle::State::RunAssociationEventHandler,
-              this, runner_, PEER_CLOSED_BEFORE_ASSOCIATION));
-    }
-  }
-
-  bool NotifyAssociation(
-      InterfaceId id,
-      scoped_refptr<AssociatedGroupController> peer_group_controller) {
-    scoped_refptr<State> cached_peer_state;
-    {
-      internal::MayAutoLock locker(&lock_);
-
-      DCHECK(pending_association_);
-      pending_association_ = false;
-      cached_peer_state = std::move(peer_state_);
-    }
-
-    if (cached_peer_state) {
-      cached_peer_state->OnAssociated(id, std::move(peer_group_controller));
-      return true;
-    }
-    return false;
-  }
-
-  bool is_valid() const {
-    internal::MayAutoLock locker(&lock_);
-    return pending_association_ || IsValidInterfaceId(id_);
-  }
-
-  bool pending_association() const {
-    internal::MayAutoLock locker(&lock_);
-    return pending_association_;
-  }
-
-  InterfaceId id() const {
-    internal::MayAutoLock locker(&lock_);
-    return id_;
-  }
-
-  AssociatedGroupController* group_controller() const {
-    internal::MayAutoLock locker(&lock_);
-    return group_controller_.get();
-  }
-
-  const base::Optional<DisconnectReason>& disconnect_reason() const {
-    internal::MayAutoLock locker(&lock_);
-    return disconnect_reason_;
-  }
-
- private:
-  friend class base::RefCountedThreadSafe<State>;
-
-  ~State() {
-    DCHECK(!pending_association_);
-    DCHECK(!IsValidInterfaceId(id_));
-  }
-
-  // Called by the peer, maybe from a different thread.
-  void OnAssociated(InterfaceId id,
-                    scoped_refptr<AssociatedGroupController> group_controller) {
-    AssociationEventCallback handler;
-    {
-      internal::MayAutoLock locker(&lock_);
-
-      // There may be race between Close() of endpoint A and
-      // NotifyPeerAssociation() of endpoint A_peer on different threads.
-      // Therefore, it is possible that endpoint A has been closed but it
-      // still gets OnAssociated() call from its peer.
-      if (!pending_association_)
-        return;
-
-      pending_association_ = false;
-      peer_state_ = nullptr;
-      id_ = id;
-      group_controller_ = std::move(group_controller);
-
-      if (!association_event_handler_.is_null()) {
-        if (runner_->BelongsToCurrentThread()) {
-          handler = std::move(association_event_handler_);
-          runner_ = nullptr;
-        } else {
-          runner_->PostTask(FROM_HERE,
-                            base::Bind(&ScopedInterfaceEndpointHandle::State::
-                                           RunAssociationEventHandler,
-                                       this, runner_, ASSOCIATED));
-        }
-      }
-    }
-
-    if (!handler.is_null())
-      std::move(handler).Run(ASSOCIATED);
-  }
-
-  // Called by the peer, maybe from a different thread.
-  void OnPeerClosedBeforeAssociation(
-      const base::Optional<DisconnectReason>& reason) {
-    AssociationEventCallback handler;
-    {
-      internal::MayAutoLock locker(&lock_);
-
-      // There may be race between Close()/NotifyPeerAssociation() of endpoint
-      // A and Close() of endpoint A_peer on different threads.
-      // Therefore, it is possible that endpoint A is not in pending association
-      // state but still gets OnPeerClosedBeforeAssociation() call from its
-      // peer.
-      if (!pending_association_)
-        return;
-
-      disconnect_reason_ = reason;
-      // NOTE: This handle itself is still pending.
-      peer_state_ = nullptr;
-
-      if (!association_event_handler_.is_null()) {
-        if (runner_->BelongsToCurrentThread()) {
-          handler = std::move(association_event_handler_);
-          runner_ = nullptr;
-        } else {
-          runner_->PostTask(
-              FROM_HERE,
-              base::Bind(&ScopedInterfaceEndpointHandle::State::
-                             RunAssociationEventHandler,
-                         this, runner_, PEER_CLOSED_BEFORE_ASSOCIATION));
-        }
-      }
-    }
-
-    if (!handler.is_null())
-      std::move(handler).Run(PEER_CLOSED_BEFORE_ASSOCIATION);
-  }
-
-  void RunAssociationEventHandler(
-      scoped_refptr<base::SingleThreadTaskRunner> posted_to_runner,
-      AssociationEvent event) {
-    AssociationEventCallback handler;
-
-    {
-      internal::MayAutoLock locker(&lock_);
-      if (posted_to_runner == runner_) {
-        runner_ = nullptr;
-        handler = std::move(association_event_handler_);
-      }
-    }
-
-    if (!handler.is_null())
-      std::move(handler).Run(event);
-  }
-
-  // Protects the following members if the handle is initially set to pending
-  // association.
-  mutable base::Optional<base::Lock> lock_;
-
-  bool pending_association_ = false;
-  base::Optional<DisconnectReason> disconnect_reason_;
-
-  scoped_refptr<State> peer_state_;
-
-  AssociationEventCallback association_event_handler_;
-  scoped_refptr<base::SingleThreadTaskRunner> runner_;
-
-  InterfaceId id_ = kInvalidInterfaceId;
-  scoped_refptr<AssociatedGroupController> group_controller_;
-
-  DISALLOW_COPY_AND_ASSIGN(State);
-};
-
-// ScopedInterfaceEndpointHandle -----------------------------------------------
-
-// static
-void ScopedInterfaceEndpointHandle::CreatePairPendingAssociation(
-    ScopedInterfaceEndpointHandle* handle0,
-    ScopedInterfaceEndpointHandle* handle1) {
-  ScopedInterfaceEndpointHandle result0;
-  ScopedInterfaceEndpointHandle result1;
-  result0.state_->InitPendingState(result1.state_);
-  result1.state_->InitPendingState(result0.state_);
-
-  *handle0 = std::move(result0);
-  *handle1 = std::move(result1);
-}
-
 ScopedInterfaceEndpointHandle::ScopedInterfaceEndpointHandle()
-    : state_(new State) {}
+    : ScopedInterfaceEndpointHandle(kInvalidInterfaceId, true, nullptr) {}
 
 ScopedInterfaceEndpointHandle::ScopedInterfaceEndpointHandle(
     ScopedInterfaceEndpointHandle&& other)
-    : state_(new State) {
-  state_.swap(other.state_);
+    : id_(other.id_), is_local_(other.is_local_) {
+  group_controller_.swap(other.group_controller_);
+  other.id_ = kInvalidInterfaceId;
 }
 
 ScopedInterfaceEndpointHandle::~ScopedInterfaceEndpointHandle() {
-  state_->Close(base::nullopt);
+  reset();
 }
 
 ScopedInterfaceEndpointHandle& ScopedInterfaceEndpointHandle::operator=(
     ScopedInterfaceEndpointHandle&& other) {
   reset();
-  state_.swap(other.state_);
-  return *this;
-}
+  swap(other);
 
-bool ScopedInterfaceEndpointHandle::is_valid() const {
-  return state_->is_valid();
+  return *this;
 }
 
-bool ScopedInterfaceEndpointHandle::pending_association() const {
-  return state_->pending_association();
-}
+void ScopedInterfaceEndpointHandle::reset() {
+  if (!IsValidInterfaceId(id_))
+    return;
 
-InterfaceId ScopedInterfaceEndpointHandle::id() const {
-  return state_->id();
-}
+  group_controller_->CloseEndpointHandle(id_, is_local_);
 
-AssociatedGroupController* ScopedInterfaceEndpointHandle::group_controller()
-    const {
-  return state_->group_controller();
+  id_ = kInvalidInterfaceId;
+  is_local_ = true;
+  group_controller_ = nullptr;
 }
 
-const base::Optional<DisconnectReason>&
-ScopedInterfaceEndpointHandle::disconnect_reason() const {
-  return state_->disconnect_reason();
+void ScopedInterfaceEndpointHandle::swap(ScopedInterfaceEndpointHandle& other) {
+  using std::swap;
+  swap(other.id_, id_);
+  swap(other.is_local_, is_local_);
+  swap(other.group_controller_, group_controller_);
 }
 
-void ScopedInterfaceEndpointHandle::SetAssociationEventHandler(
-    AssociationEventCallback handler) {
-  state_->SetAssociationEventHandler(std::move(handler));
-}
+InterfaceId ScopedInterfaceEndpointHandle::release() {
+  InterfaceId result = id_;
 
-void ScopedInterfaceEndpointHandle::reset() {
-  ResetInternal(base::nullopt);
-}
+  id_ = kInvalidInterfaceId;
+  is_local_ = true;
+  group_controller_ = nullptr;
 
-void ScopedInterfaceEndpointHandle::ResetWithReason(
-    uint32_t custom_reason,
-    const std::string& description) {
-  ResetInternal(DisconnectReason(custom_reason, description));
+  return result;
 }
 
 ScopedInterfaceEndpointHandle::ScopedInterfaceEndpointHandle(
     InterfaceId id,
+    bool is_local,
     scoped_refptr<AssociatedGroupController> group_controller)
-    : state_(new State(id, std::move(group_controller))) {
-  DCHECK(!IsValidInterfaceId(state_->id()) || state_->group_controller());
-}
-
-bool ScopedInterfaceEndpointHandle::NotifyAssociation(
-    InterfaceId id,
-    scoped_refptr<AssociatedGroupController> peer_group_controller) {
-  return state_->NotifyAssociation(id, peer_group_controller);
-}
-
-void ScopedInterfaceEndpointHandle::ResetInternal(
-    const base::Optional<DisconnectReason>& reason) {
-  scoped_refptr<State> new_state(new State);
-  state_->Close(reason);
-  state_.swap(new_state);
-}
-
-base::Callback<AssociatedGroupController*()>
-ScopedInterfaceEndpointHandle::CreateGroupControllerGetter() const {
-  // We allow this callback to be run on any thread. If this handle is created
-  // in non-pending state, we don't have a lock but it should still be safe
-  // because the group controller never changes.
-  return base::Bind(&State::group_controller, state_);
+    : id_(id),
+      is_local_(is_local),
+      group_controller_(std::move(group_controller)) {
+  DCHECK(!IsValidInterfaceId(id) || group_controller_);
 }
 
 }  // namespace mojo