Mojo: Add move semantics to RemotePtr<T>

Also, put Connector into the mojo::internal:: namespace.

BUG=325806
R=viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/103193004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238814 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 98 insertions, 18 deletions

diff --git a/mojo/public/bindings/lib/connector.cc b/mojo/public/bindings/lib/connector.cc
index 6b701a7..872fbbf 100644
--- a/mojo/public/bindings/lib/connector.cc
+++ b/mojo/public/bindings/lib/connector.cc
@@ -10,6 +10,7 @@
 #include <algorithm>
 
 namespace mojo {
+namespace internal {
 
 // ----------------------------------------------------------------------------
 
@@ -173,4 +174,5 @@ void Connector::Callback::OnHandleReady(MojoResult result) {
   owner->OnHandleReady(this, result);
 }
 
+}  // namespace internal
 }  // namespace mojo
diff --git a/mojo/public/bindings/lib/connector.h b/mojo/public/bindings/lib/connector.h
index 1fbf1d8..b235437 100644
--- a/mojo/public/bindings/lib/connector.h
+++ b/mojo/public/bindings/lib/connector.h
@@ -11,6 +11,7 @@
 #include "mojo/public/system/core_cpp.h"
 
 namespace mojo {
+namespace internal {
 
 // The Connector class is responsible for performing read/write operations on a
 // MessagePipe. It writes messages it receives through the MessageReceiver
@@ -73,6 +74,7 @@ class Connector : public MessageReceiver {
   MOJO_DISALLOW_COPY_AND_ASSIGN(Connector);
 };
 
+}  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_BINDINGS_LIB_CONNECTOR_H_
diff --git a/mojo/public/bindings/lib/remote_ptr.h b/mojo/public/bindings/lib/remote_ptr.h
index 26056e9..58f77ad 100644
--- a/mojo/public/bindings/lib/remote_ptr.h
+++ b/mojo/public/bindings/lib/remote_ptr.h
@@ -5,7 +5,10 @@
 #ifndef MOJO_PUBLIC_BINDINGS_LIB_REMOTE_PTR_H_
 #define MOJO_PUBLIC_BINDINGS_LIB_REMOTE_PTR_H_
 
+#include <assert.h>
+
 #include "mojo/public/bindings/lib/connector.h"
+#include "mojo/public/system/macros.h"
 
 namespace mojo {
 
@@ -47,29 +50,70 @@ namespace mojo {
 //
 template <typename S>
 class RemotePtr {
+  MOJO_MOVE_ONLY_TYPE_FOR_CPP_03(RemotePtr, RValue);
+
  public:
+  RemotePtr() : state_(NULL) {}
   explicit RemotePtr(ScopedMessagePipeHandle message_pipe)
-      : connector_(message_pipe.Pass()),
-        proxy_(&connector_) {
+      : state_(new State(message_pipe.Pass())) {
+  }
+
+  // Move-only constructor and operator=.
+  RemotePtr(RValue other) : state_(other.object->release()) {}
+  RemotePtr& operator=(RValue other) {
+    state_ = other.object->release();
+    return *this;
+  }
+
+  ~RemotePtr() {
+    delete state_;
+  }
+
+  bool is_valid() const {
+    return !!state_;
   }
 
   S* get() {
-    return &proxy_;
+    assert(state_);
+    return &state_->proxy;
   }
 
   S* operator->() {
     return get();
   }
 
+  void reset() {
+    delete state_;
+    state_ = NULL;
+  }
+
+  void reset(ScopedMessagePipeHandle message_pipe) {
+    delete state_;
+    state_ = new State(message_pipe.Pass());
+  }
+
   void SetPeer(typename S::_Peer::_Stub* peer) {
-    connector_.SetIncomingReceiver(peer);
+    assert(state_);
+    state_->connector.SetIncomingReceiver(peer);
   }
 
  private:
-  Connector connector_;
-  typename S::_Proxy proxy_;
+  struct State {
+    State(ScopedMessagePipeHandle message_pipe)
+        : connector(message_pipe.Pass()),
+          proxy(&connector) {
+    }
+    internal::Connector connector;
+    typename S::_Proxy proxy;
+  };
+
+  State* release() {
+    State* state = state_;
+    state_ = NULL;
+    return state;
+  }
 
-  MOJO_DISALLOW_COPY_AND_ASSIGN(RemotePtr);
+  State* state_;
 };
 
 }  // namespace mojo
diff --git a/mojo/public/tests/bindings_connector_unittest.cc b/mojo/public/tests/bindings_connector_unittest.cc
index 47052ab..737f26a 100644
--- a/mojo/public/tests/bindings_connector_unittest.cc
+++ b/mojo/public/tests/bindings_connector_unittest.cc
@@ -71,8 +71,8 @@ class BindingsConnectorTest : public testing::Test {
 };
 
 TEST_F(BindingsConnectorTest, Basic) {
-  Connector connector0(handle0_.Pass());
-  Connector connector1(handle1_.Pass());
+  internal::Connector connector0(handle0_.Pass());
+  internal::Connector connector1(handle1_.Pass());
 
   const char kText[] = "hello world";
 
@@ -97,8 +97,8 @@ TEST_F(BindingsConnectorTest, Basic) {
 }
 
 TEST_F(BindingsConnectorTest, Basic_EarlyIncomingReceiver) {
-  Connector connector0(handle0_.Pass());
-  Connector connector1(handle1_.Pass());
+  internal::Connector connector0(handle0_.Pass());
+  internal::Connector connector1(handle1_.Pass());
 
   MessageAccumulator accumulator;
   connector1.SetIncomingReceiver(&accumulator);
@@ -123,8 +123,8 @@ TEST_F(BindingsConnectorTest, Basic_EarlyIncomingReceiver) {
 }
 
 TEST_F(BindingsConnectorTest, Basic_TwoMessages) {
-  Connector connector0(handle0_.Pass());
-  Connector connector1(handle1_.Pass());
+  internal::Connector connector0(handle0_.Pass());
+  internal::Connector connector1(handle1_.Pass());
 
   const char* kText[] = { "hello", "world" };
 
@@ -155,7 +155,7 @@ TEST_F(BindingsConnectorTest, Basic_TwoMessages) {
 TEST_F(BindingsConnectorTest, WriteToClosedPipe) {
   // Leak this, so the closed handle isn't closed again.
   MojoHandle mojo_handle = handle0_.get().value();
-  Connector* connector0 = new Connector(handle0_.Pass());
+  internal::Connector* connector0 = new internal::Connector(handle0_.Pass());
 
   const char kText[] = "hello world";
 
@@ -173,8 +173,8 @@ TEST_F(BindingsConnectorTest, WriteToClosedPipe) {
 
 // Enable this test once MojoWriteMessage supports passing handles.
 TEST_F(BindingsConnectorTest, MessageWithHandles) {
-  Connector connector0(handle0_.Pass());
-  Connector connector1(handle1_.Pass());
+  internal::Connector connector0(handle0_.Pass());
+  internal::Connector connector1(handle1_.Pass());
 
   const char kText[] = "hello world";
 
@@ -212,8 +212,8 @@ TEST_F(BindingsConnectorTest, MessageWithHandles) {
   smph.reset(MessagePipeHandle(message_received.handles[0].value()));
   message_received.handles[0] = Handle();  // |smph| now owns this handle.
 
-  Connector connector_received(smph.Pass());
-  Connector connector_original(handles[1].Pass());
+  internal::Connector connector_received(smph.Pass());
+  internal::Connector connector_original(handles[1].Pass());
 
   AllocMessage(kText, &message);
 
diff --git a/mojo/public/tests/bindings_remote_ptr_unittest.cc b/mojo/public/tests/bindings_remote_ptr_unittest.cc
index ebad72a..c236695 100644
--- a/mojo/public/tests/bindings_remote_ptr_unittest.cc
+++ b/mojo/public/tests/bindings_remote_ptr_unittest.cc
@@ -111,5 +111,37 @@ TEST_F(BindingsRemotePtrTest, EndToEnd) {
   EXPECT_EQ(10.0, calculator_ui.GetOutput());
 }
 
+TEST_F(BindingsRemotePtrTest, Movable) {
+  RemotePtr<math::Calculator> a;
+  RemotePtr<math::Calculator> b(pipe0_.Pass());
+
+  EXPECT_FALSE(a.is_valid());
+  EXPECT_TRUE(b.is_valid());
+
+  a = b.Pass();
+
+  EXPECT_TRUE(a.is_valid());
+  EXPECT_FALSE(b.is_valid());
+}
+
+TEST_F(BindingsRemotePtrTest, Resettable) {
+  RemotePtr<math::Calculator> a;
+
+  EXPECT_FALSE(a.is_valid());
+
+  MessagePipeHandle handle = pipe0_.get();
+
+  a.reset(pipe0_.Pass());
+
+  EXPECT_TRUE(a.is_valid());
+
+  a.reset();
+
+  EXPECT_FALSE(a.is_valid());
+
+  // Test that handle was closed.
+  EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, CloseRaw(handle));
+}
+
 }  // namespace test
 }  // namespace mojo