Pass unique_ptr of InputChannel to Connection

This gets us closer to the goal of storing unique_ptr of InputChannel
inside the InputPublisher.

In this CL, we are still allowing the "copy" and "dup" functions to
exist. Removing those requires significant refactoring on the Java side,
including the jni layer and object ownership models.

Test: TEST=inputflinger_tests; m $TEST && $ANDROID_HOST_OUT/nativetest64/$TEST/$TEST
Bug: 161009324
Change-Id: If6f44d78c7fc9f3e12729068de1753847abf0ebb

7 files changed, 34 insertions, 33 deletions

diff --git a/include/input/InputTransport.h b/include/input/InputTransport.h
index d53e8c6cce..42dcd3c394 100644
--- a/include/input/InputTransport.h
+++ b/include/input/InputTransport.h
@@ -301,6 +301,15 @@ public:
     void copyTo(android::os::InputChannelCore& outChannel) const;
 
     /**
+     * Similar to "copyTo", but it takes ownership of the provided InputChannel (and after this is
+     * called, it destroys it).
+     * @param from the InputChannel that should be converted to InputChannelCore
+     * @param outChannel the pre-allocated InputChannelCore to which to transfer the 'from' channel
+     */
+    static void moveChannel(std::unique_ptr<InputChannel> from,
+                            android::os::InputChannelCore& outChannel);
+
+    /**
      * The connection token is used to identify the input connection, i.e.
      * the pair of input channels that were created simultaneously. Input channels
      * are always created in pairs, and the token can be used to find the server-side
@@ -333,7 +342,7 @@ public:
     ~InputPublisher();
 
     /* Gets the underlying input channel. */
-    inline std::shared_ptr<InputChannel> getChannel() const { return mChannel; }
+    inline InputChannel& getChannel() const { return *mChannel; }
 
     /* Publishes a key event to the input channel.
      *
diff --git a/libs/input/InputTransport.cpp b/libs/input/InputTransport.cpp
index 0e0e80dc79..e49f4eb6f6 100644
--- a/libs/input/InputTransport.cpp
+++ b/libs/input/InputTransport.cpp
@@ -584,6 +584,13 @@ void InputChannel::copyTo(android::os::InputChannelCore& outChannel) const {
     outChannel.token = getConnectionToken();
 }
 
+void InputChannel::moveChannel(std::unique_ptr<InputChannel> from,
+                               android::os::InputChannelCore& outChannel) {
+    outChannel.name = from->getName();
+    outChannel.fd = android::os::ParcelFileDescriptor(std::move(from->fd));
+    outChannel.token = from->getConnectionToken();
+}
+
 sp<IBinder> InputChannel::getConnectionToken() const {
     return token;
 }
@@ -591,7 +598,7 @@ sp<IBinder> InputChannel::getConnectionToken() const {
 // --- InputPublisher ---
 
 InputPublisher::InputPublisher(const std::shared_ptr<InputChannel>& channel)
-      : mChannel(channel), mInputVerifier(channel->getName()) {}
+      : mChannel(channel), mInputVerifier(mChannel->getName()) {}
 
 InputPublisher::~InputPublisher() {
 }
diff --git a/libs/input/tests/InputPublisherAndConsumer_test.cpp b/libs/input/tests/InputPublisherAndConsumer_test.cpp
index 2000335521..35430207f9 100644
--- a/libs/input/tests/InputPublisherAndConsumer_test.cpp
+++ b/libs/input/tests/InputPublisherAndConsumer_test.cpp
@@ -220,7 +220,6 @@ void waitUntilInputAvailable(const InputConsumer& inputConsumer) {
 
 class InputPublisherAndConsumerTest : public testing::Test {
 protected:
-    std::shared_ptr<InputChannel> mServerChannel, mClientChannel;
     std::unique_ptr<InputPublisher> mPublisher;
     std::unique_ptr<InputConsumer> mConsumer;
     PreallocatedInputEventFactory mEventFactory;
@@ -230,11 +229,9 @@ protected:
         status_t result = InputChannel::openInputChannelPair("channel name",
                 serverChannel, clientChannel);
         ASSERT_EQ(OK, result);
-        mServerChannel = std::move(serverChannel);
-        mClientChannel = std::move(clientChannel);
 
-        mPublisher = std::make_unique<InputPublisher>(mServerChannel);
-        mConsumer = std::make_unique<InputConsumer>(mClientChannel);
+        mPublisher = std::make_unique<InputPublisher>(std::move(serverChannel));
+        mConsumer = std::make_unique<InputConsumer>(std::move(clientChannel));
     }
 
     void publishAndConsumeKeyEvent();
@@ -254,11 +251,7 @@ private:
 };
 
 TEST_F(InputPublisherAndConsumerTest, GetChannel_ReturnsTheChannel) {
-    ASSERT_NE(nullptr, mPublisher->getChannel());
-    ASSERT_NE(nullptr, mConsumer->getChannel());
-    EXPECT_EQ(mServerChannel.get(), mPublisher->getChannel().get());
-    EXPECT_EQ(mClientChannel.get(), mConsumer->getChannel().get());
-    ASSERT_EQ(mPublisher->getChannel()->getConnectionToken(),
+    ASSERT_EQ(mPublisher->getChannel().getConnectionToken(),
               mConsumer->getChannel()->getConnectionToken());
 }
 
diff --git a/services/inputflinger/InputManager.cpp b/services/inputflinger/InputManager.cpp
index 823df67d16..ae066c0f4a 100644
--- a/services/inputflinger/InputManager.cpp
+++ b/services/inputflinger/InputManager.cpp
@@ -277,7 +277,7 @@ binder::Status InputManager::createInputChannel(const std::string& name,
         return binder::Status::fromExceptionCode(exceptionCodeFromStatusT(channel.error().code()),
                                                  channel.error().message().c_str());
     }
-    (*channel)->copyTo(*outChannel);
+    InputChannel::moveChannel(std::move(*channel), *outChannel);
     return binder::Status::ok();
 }
 
diff --git a/services/inputflinger/dispatcher/Connection.cpp b/services/inputflinger/dispatcher/Connection.cpp
index c7963c0512..9dee66f0f8 100644
--- a/services/inputflinger/dispatcher/Connection.cpp
+++ b/services/inputflinger/dispatcher/Connection.cpp
@@ -20,15 +20,15 @@
 
 namespace android::inputdispatcher {
 
-Connection::Connection(const std::shared_ptr<InputChannel>& inputChannel, bool monitor,
+Connection::Connection(std::unique_ptr<InputChannel> inputChannel, bool monitor,
                        const IdGenerator& idGenerator)
       : status(Status::NORMAL),
         monitor(monitor),
-        inputPublisher(inputChannel),
+        inputPublisher(std::move(inputChannel)),
         inputState(idGenerator) {}
 
 sp<IBinder> Connection::getToken() const {
-    return inputPublisher.getChannel()->getConnectionToken();
+    return inputPublisher.getChannel().getConnectionToken();
 };
 
 } // namespace android::inputdispatcher
diff --git a/services/inputflinger/dispatcher/Connection.h b/services/inputflinger/dispatcher/Connection.h
index 8d7f182a7d..a834a8cf86 100644
--- a/services/inputflinger/dispatcher/Connection.h
+++ b/services/inputflinger/dispatcher/Connection.h
@@ -58,11 +58,11 @@ public:
     // yet received a "finished" response from the application.
     std::deque<std::unique_ptr<DispatchEntry>> waitQueue;
 
-    Connection(const std::shared_ptr<InputChannel>& inputChannel, bool monitor,
+    Connection(std::unique_ptr<InputChannel> inputChannel, bool monitor,
                const IdGenerator& idGenerator);
 
     inline const std::string getInputChannelName() const {
-        return inputPublisher.getChannel()->getName();
+        return inputPublisher.getChannel().getName();
     }
 
     sp<IBinder> getToken() const;
diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index a62e23a930..af72eb9bcb 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -436,15 +436,6 @@ std::unique_ptr<DispatchEntry> createDispatchEntry(const InputTarget& inputTarge
     return dispatchEntry;
 }
 
-status_t openInputChannelPair(const std::string& name, std::shared_ptr<InputChannel>& serverChannel,
-                              std::unique_ptr<InputChannel>& clientChannel) {
-    std::unique_ptr<InputChannel> uniqueServerChannel;
-    status_t result = InputChannel::openInputChannelPair(name, uniqueServerChannel, clientChannel);
-
-    serverChannel = std::move(uniqueServerChannel);
-    return result;
-}
-
 template <typename T>
 bool sharedPointersEqual(const std::shared_ptr<T>& lhs, const std::shared_ptr<T>& rhs) {
     if (lhs == nullptr && rhs == nullptr) {
@@ -5805,7 +5796,7 @@ void InputDispatcher::dumpDispatchStateLocked(std::string& dump) const {
         for (const auto& [token, connection] : mConnectionsByToken) {
             dump += StringPrintf(INDENT2 "%i: channelName='%s', "
                                          "status=%s, monitor=%s, responsive=%s\n",
-                                 connection->inputPublisher.getChannel()->getFd(),
+                                 connection->inputPublisher.getChannel().getFd(),
                                  connection->getInputChannelName().c_str(),
                                  ftl::enum_string(connection->status).c_str(),
                                  toString(connection->monitor), toString(connection->responsive));
@@ -5916,9 +5907,9 @@ Result<std::unique_ptr<InputChannel>> InputDispatcher::createInputChannel(const
 Result<std::unique_ptr<InputChannel>> InputDispatcher::createInputMonitor(int32_t displayId,
                                                                           const std::string& name,
                                                                           gui::Pid pid) {
-    std::shared_ptr<InputChannel> serverChannel;
+    std::unique_ptr<InputChannel> serverChannel;
     std::unique_ptr<InputChannel> clientChannel;
-    status_t result = openInputChannelPair(name, serverChannel, clientChannel);
+    status_t result = InputChannel::openInputChannelPair(name, serverChannel, clientChannel);
     if (result) {
         return base::Error(result) << "Failed to open input channel pair with name " << name;
     }
@@ -5931,10 +5922,11 @@ Result<std::unique_ptr<InputChannel>> InputDispatcher::createInputMonitor(int32_
                                           << " without a specified display.";
         }
 
-        std::shared_ptr<Connection> connection =
-                std::make_shared<Connection>(serverChannel, /*monitor=*/true, mIdGenerator);
         const sp<IBinder>& token = serverChannel->getConnectionToken();
         const int fd = serverChannel->getFd();
+        std::shared_ptr<Connection> connection =
+                std::make_shared<Connection>(std::move(serverChannel), /*monitor=*/true,
+                                             mIdGenerator);
 
         auto [_, inserted] = mConnectionsByToken.emplace(token, connection);
         if (!inserted) {
@@ -5985,7 +5977,7 @@ status_t InputDispatcher::removeInputChannelLocked(const sp<IBinder>& connection
         removeMonitorChannelLocked(connectionToken);
     }
 
-    mLooper->removeFd(connection->inputPublisher.getChannel()->getFd());
+    mLooper->removeFd(connection->inputPublisher.getChannel().getFd());
 
     nsecs_t currentTime = now();
     abortBrokenDispatchCycleLocked(currentTime, connection, notify);