libudx: Move ServiceDispatcher from libpdx_uds to libpdx

The two separate implementations of ServiceDispatcher for UDS and ServiceFS
are practically identical. Moved the implementation into the base libpdx lib,
and removed the transport-specific versions.

Bug: None
Test: `m -j32` succeeds; pdx_tests, pdx_servicefs_tests, pdx_uds_tests pass
Change-Id: I2344f4f23bc3da27eb7b192344844b87660e8610
diff --git a/libs/vr/libpdx/Android.bp b/libs/vr/libpdx/Android.bp
index f55e994..8fce140 100644
--- a/libs/vr/libpdx/Android.bp
+++ b/libs/vr/libpdx/Android.bp
@@ -5,12 +5,15 @@
         "-Wall",
         "-Wextra",
         "-Werror",
+        "-DLOG_TAG=\"libpdx\"",
+        "-DTRACE=0",
     ],
     export_include_dirs: ["private"],
     local_include_dirs: ["private"],
     srcs: [
         "client.cpp",
         "service.cpp",
+        "service_dispatcher.cpp",
         "status.cpp",
     ],
 }
diff --git a/libs/vr/libpdx/client.cpp b/libs/vr/libpdx/client.cpp
index bfa2d87..a01c4d6 100644
--- a/libs/vr/libpdx/client.cpp
+++ b/libs/vr/libpdx/client.cpp
@@ -1,6 +1,5 @@
 #include "pdx/client.h"
 
-#define LOG_TAG "ServiceFramework"
 #include <log/log.h>
 
 #include <pdx/trace.h>
diff --git a/libs/vr/libpdx/mock_tests.cpp b/libs/vr/libpdx/mock_tests.cpp
index 76fd154..4143837 100644
--- a/libs/vr/libpdx/mock_tests.cpp
+++ b/libs/vr/libpdx/mock_tests.cpp
@@ -3,7 +3,6 @@
 #include <pdx/mock_client_channel_factory.h>
 #include <pdx/mock_message_reader.h>
 #include <pdx/mock_message_writer.h>
-#include <pdx/mock_service_dispatcher.h>
 #include <pdx/mock_service_endpoint.h>
 
 TEST(MockTypes, Instantiation) {
@@ -15,6 +14,5 @@
   android::pdx::MockMessageReader message_reader;
   android::pdx::MockOutputResourceMapper output_resource_mapper;
   android::pdx::MockMessageWriter message_writer;
-  android::pdx::MockServiceDispatcher service_dispatcher;
   android::pdx::MockEndpoint endpoint;
 }
diff --git a/libs/vr/libpdx/private/pdx/mock_service_dispatcher.h b/libs/vr/libpdx/private/pdx/mock_service_dispatcher.h
deleted file mode 100644
index 9b51d30..0000000
--- a/libs/vr/libpdx/private/pdx/mock_service_dispatcher.h
+++ /dev/null
@@ -1,24 +0,0 @@
-#ifndef ANDROID_PDX_MOCK_SERVICE_DISPATCHER_H_
-#define ANDROID_PDX_MOCK_SERVICE_DISPATCHER_H_
-
-#include <gmock/gmock.h>
-#include <pdx/service_dispatcher.h>
-
-namespace android {
-namespace pdx {
-
-class MockServiceDispatcher : public ServiceDispatcher {
- public:
-  MOCK_METHOD1(AddService, int(const std::shared_ptr<Service>& service));
-  MOCK_METHOD1(RemoveService, int(const std::shared_ptr<Service>& service));
-  MOCK_METHOD0(ReceiveAndDispatch, int());
-  MOCK_METHOD1(ReceiveAndDispatch, int(int timeout));
-  MOCK_METHOD0(EnterDispatchLoop, int());
-  MOCK_METHOD1(SetCanceled, void(bool cancel));
-  MOCK_CONST_METHOD0(IsCanceled, bool());
-};
-
-}  // namespace pdx
-}  // namespace android
-
-#endif  // ANDROID_PDX_MOCK_SERVICE_DISPATCHER_H_
diff --git a/libs/vr/libpdx/private/pdx/mock_service_endpoint.h b/libs/vr/libpdx/private/pdx/mock_service_endpoint.h
index e741d4a..7f829e7 100644
--- a/libs/vr/libpdx/private/pdx/mock_service_endpoint.h
+++ b/libs/vr/libpdx/private/pdx/mock_service_endpoint.h
@@ -66,6 +66,7 @@
   MOCK_METHOD0(AllocateMessageState, void*());
   MOCK_METHOD1(FreeMessageState, void(void* state));
   MOCK_METHOD0(Cancel, Status<void>());
+  MOCK_CONST_METHOD0(epoll_fd, int());
 };
 
 }  // namespace pdx
diff --git a/libs/vr/libpdx/private/pdx/service_dispatcher.h b/libs/vr/libpdx/private/pdx/service_dispatcher.h
index c5e342a..bd27000 100644
--- a/libs/vr/libpdx/private/pdx/service_dispatcher.h
+++ b/libs/vr/libpdx/private/pdx/service_dispatcher.h
@@ -2,6 +2,11 @@
 #define ANDROID_PDX_SERVICE_DISPATCHER_H_
 
 #include <memory>
+#include <mutex>
+#include <unordered_map>
+#include <vector>
+
+#include <pdx/file_handle.h>
 
 namespace android {
 namespace pdx {
@@ -15,7 +20,10 @@
  */
 class ServiceDispatcher {
  public:
-  virtual ~ServiceDispatcher() = default;
+  // Get a new instance of ServiceDispatcher, or return nullptr if init failed.
+  static std::unique_ptr<ServiceDispatcher> Create();
+
+  ~ServiceDispatcher();
 
   /*
    * Adds a service to the list of services handled by this dispatcher. This
@@ -24,7 +32,7 @@
    *
    * Returns 0 on success; -EEXIST if the service was already added.
    */
-  virtual int AddService(const std::shared_ptr<Service>& service) = 0;
+  int AddService(const std::shared_ptr<Service>& service);
 
   /*
    * Removes a service from this dispatcher. This will fail if any threads are
@@ -33,7 +41,7 @@
    * Returns 0 on success; -ENOENT if the service was not previously added;
    * -EBUSY if there are threads in the dispatcher.
    */
-  virtual int RemoveService(const std::shared_ptr<Service>& service) = 0;
+  int RemoveService(const std::shared_ptr<Service>& service);
 
   /*
    * Receive and dispatch one set of messages. Multiple threads may enter this
@@ -42,14 +50,14 @@
    * cycle, requiring an external loop. This is useful when other work needs
    * to be done in the service dispatch loop.
    */
-  virtual int ReceiveAndDispatch() = 0;
+  int ReceiveAndDispatch();
 
   /*
    * Same as above with timeout in milliseconds. A negative value means
    * infinite timeout, while a value of 0 means return immediately if no
    * messages are available to receive.
    */
-  virtual int ReceiveAndDispatch(int timeout) = 0;
+  int ReceiveAndDispatch(int timeout);
 
   /*
    * Receive and dispatch messages until canceled. When more than one thread
@@ -58,19 +66,39 @@
    * hands Message instances (via move assignment) over to a queue of threads
    * (or perhaps one of several) to handle.
    */
-  virtual int EnterDispatchLoop() = 0;
+  int EnterDispatchLoop();
 
   /*
    * Sets the canceled state of the dispatcher. When canceled is true, any
    * threads blocked waiting for messages will return. This method waits until
    * all dispatch threads have exited the dispatcher.
    */
-  virtual void SetCanceled(bool cancel) = 0;
+  void SetCanceled(bool cancel);
 
   /*
    * Gets the canceled state of the dispatcher.
    */
-  virtual bool IsCanceled() const = 0;
+  bool IsCanceled() const;
+
+ private:
+  ServiceDispatcher();
+
+  // Internal thread accounting.
+  int ThreadEnter();
+  void ThreadExit();
+
+  std::mutex mutex_;
+  std::condition_variable condition_;
+  std::atomic<bool> canceled_{false};
+
+  std::vector<std::shared_ptr<Service>> services_;
+
+  int thread_count_ = 0;
+  LocalHandle event_fd_;
+  LocalHandle epoll_fd_;
+
+  ServiceDispatcher(const ServiceDispatcher&) = delete;
+  void operator=(const ServiceDispatcher&) = delete;
 };
 
 }  // namespace pdx
diff --git a/libs/vr/libpdx/private/pdx/service_endpoint.h b/libs/vr/libpdx/private/pdx/service_endpoint.h
index 28bd6bc..d581894 100644
--- a/libs/vr/libpdx/private/pdx/service_endpoint.h
+++ b/libs/vr/libpdx/private/pdx/service_endpoint.h
@@ -136,6 +136,10 @@
   // Cancels the endpoint, unblocking any receiver threads waiting for a
   // message.
   virtual Status<void> Cancel() = 0;
+
+  // Returns an fd that can be used with epoll() to wait for incoming messages
+  // from this endpoint.
+  virtual int epoll_fd() const = 0;
 };
 
 }  // namespace pdx
diff --git a/libs/vr/libpdx/service.cpp b/libs/vr/libpdx/service.cpp
index fab4770..1d3b62a 100644
--- a/libs/vr/libpdx/service.cpp
+++ b/libs/vr/libpdx/service.cpp
@@ -1,4 +1,3 @@
-#define LOG_TAG "ServiceFramework"
 #include "pdx/service.h"
 
 #include <fcntl.h>
@@ -10,8 +9,6 @@
 
 #include <pdx/trace.h>
 
-#define TRACE 0
-
 namespace android {
 namespace pdx {
 
diff --git a/libs/vr/libpdx_uds/service_dispatcher.cpp b/libs/vr/libpdx/service_dispatcher.cpp
similarity index 83%
rename from libs/vr/libpdx_uds/service_dispatcher.cpp
rename to libs/vr/libpdx/service_dispatcher.cpp
index 2c52578..b112fa3 100644
--- a/libs/vr/libpdx_uds/service_dispatcher.cpp
+++ b/libs/vr/libpdx/service_dispatcher.cpp
@@ -1,26 +1,25 @@
-#include "uds/service_dispatcher.h"
+#include <pdx/service_dispatcher.h>
 
 #include <errno.h>
 #include <log/log.h>
 #include <sys/epoll.h>
 #include <sys/eventfd.h>
 
-#include "pdx/service.h"
-#include "uds/service_endpoint.h"
+#include <pdx/service.h>
+#include <pdx/service_endpoint.h>
 
 static const int kMaxEventsPerLoop = 128;
 
 namespace android {
 namespace pdx {
-namespace uds {
 
-std::unique_ptr<pdx::ServiceDispatcher> ServiceDispatcher::Create() {
+std::unique_ptr<ServiceDispatcher> ServiceDispatcher::Create() {
   std::unique_ptr<ServiceDispatcher> dispatcher{new ServiceDispatcher()};
   if (!dispatcher->epoll_fd_ || !dispatcher->event_fd_) {
     dispatcher.reset();
   }
 
-  return std::move(dispatcher);
+  return dispatcher;
 }
 
 ServiceDispatcher::ServiceDispatcher() {
@@ -70,18 +69,14 @@
 }
 
 int ServiceDispatcher::AddService(const std::shared_ptr<Service>& service) {
-  if (service->endpoint()->GetIpcTag() != Endpoint::kIpcTag)
-    return -EINVAL;
-
   std::lock_guard<std::mutex> autolock(mutex_);
 
-  auto* endpoint = static_cast<Endpoint*>(service->endpoint());
   epoll_event event;
   event.events = EPOLLIN;
   event.data.ptr = service.get();
 
-  if (epoll_ctl(epoll_fd_.Get(), EPOLL_CTL_ADD, endpoint->epoll_fd(), &event) <
-      0) {
+  if (epoll_ctl(epoll_fd_.Get(), EPOLL_CTL_ADD, service->endpoint()->epoll_fd(),
+                &event) < 0) {
     ALOGE("Failed to add service to dispatcher because: %s\n", strerror(errno));
     return -errno;
   }
@@ -91,9 +86,6 @@
 }
 
 int ServiceDispatcher::RemoveService(const std::shared_ptr<Service>& service) {
-  if (service->endpoint()->GetIpcTag() != Endpoint::kIpcTag)
-    return -EINVAL;
-
   std::lock_guard<std::mutex> autolock(mutex_);
 
   // It's dangerous to remove a service while other threads may be using it.
@@ -101,16 +93,15 @@
     return -EBUSY;
 
   epoll_event dummy;  // See BUGS in man 2 epoll_ctl.
-
-  auto* endpoint = static_cast<Endpoint*>(service->endpoint());
-  if (epoll_ctl(epoll_fd_.Get(), EPOLL_CTL_DEL, endpoint->epoll_fd(), &dummy) <
-      0) {
+  if (epoll_ctl(epoll_fd_.Get(), EPOLL_CTL_DEL, service->endpoint()->epoll_fd(),
+                &dummy) < 0) {
     ALOGE("Failed to remove service from dispatcher because: %s\n",
           strerror(errno));
     return -errno;
   }
 
-  services_.remove(service);
+  services_.erase(std::remove(services_.begin(), services_.end(), service),
+                  services_.end());
   return 0;
 }
 
@@ -139,7 +130,7 @@
       Service* service = static_cast<Service*>(events[i].data.ptr);
 
       ALOGI_IF(TRACE, "Dispatching message: fd=%d\n",
-               static_cast<Endpoint*>(service->endpoint())->epoll_fd());
+               service->endpoint()->epoll_fd());
       service->ReceiveAndDispatch();
     }
   }
@@ -171,7 +162,7 @@
         Service* service = static_cast<Service*>(events[i].data.ptr);
 
         ALOGI_IF(TRACE, "Dispatching message: fd=%d\n",
-                 static_cast<Endpoint*>(service->endpoint())->epoll_fd());
+                 service->endpoint()->epoll_fd());
         service->ReceiveAndDispatch();
       }
     }
@@ -197,6 +188,5 @@
 
 bool ServiceDispatcher::IsCanceled() const { return canceled_; }
 
-}  // namespace uds
 }  // namespace pdx
 }  // namespace android
diff --git a/libs/vr/libpdx_default_transport/private/servicefs/pdx/default_transport/service_dispatcher.h b/libs/vr/libpdx_default_transport/private/servicefs/pdx/default_transport/service_dispatcher.h
deleted file mode 100644
index 158871c..0000000
--- a/libs/vr/libpdx_default_transport/private/servicefs/pdx/default_transport/service_dispatcher.h
+++ /dev/null
@@ -1,17 +0,0 @@
-#ifndef ANDROID_PDX_DEFAULT_TRANSPORT_SERVICEFS_SERVICE_DISPATCHER_H_
-#define ANDROID_PDX_DEFAULT_TRANSPORT_SERVICEFS_SERVICE_DISPATCHER_H_
-
-#include <servicefs/service_dispatcher.h>
-
-namespace android {
-namespace pdx {
-namespace default_transport {
-
-using ServiceDispatcher = ::android::pdx::servicefs::ServiceDispatcher;
-
-}  // namespace default_transport
-}  // namespace pdx
-}  // namespace android
-
-
-#endif  // ANDROID_PDX_DEFAULT_TRANSPORT_SERVICEFS_SERVICE_DISPATCHER_H_
diff --git a/libs/vr/libpdx_default_transport/private/uds/pdx/default_transport/service_dispatcher.h b/libs/vr/libpdx_default_transport/private/uds/pdx/default_transport/service_dispatcher.h
deleted file mode 100644
index 7cb7a80..0000000
--- a/libs/vr/libpdx_default_transport/private/uds/pdx/default_transport/service_dispatcher.h
+++ /dev/null
@@ -1,17 +0,0 @@
-#ifndef ANDROID_PDX_DEFAULT_TRANSPORT_UDS_SERVICE_DISPATCHER_H_
-#define ANDROID_PDX_DEFAULT_TRANSPORT_UDS_SERVICE_DISPATCHER_H_
-
-#include <uds/service_dispatcher.h>
-
-namespace android {
-namespace pdx {
-namespace default_transport {
-
-using ServiceDispatcher = ::android::pdx::uds::ServiceDispatcher;
-
-}  // namespace default_transport
-}  // namespace pdx
-}  // namespace android
-
-
-#endif  // ANDROID_PDX_DEFAULT_TRANSPORT_UDS_SERVICE_DISPATCHER_H_
diff --git a/libs/vr/libpdx_uds/Android.bp b/libs/vr/libpdx_uds/Android.bp
index 82a5ea7..d0b7cab 100644
--- a/libs/vr/libpdx_uds/Android.bp
+++ b/libs/vr/libpdx_uds/Android.bp
@@ -16,7 +16,6 @@
         "client_channel_factory.cpp",
         "client_channel.cpp",
         "ipc_helper.cpp",
-        "service_dispatcher.cpp",
         "service_endpoint.cpp",
     ],
     static_libs: [
diff --git a/libs/vr/libpdx_uds/client_channel_tests.cpp b/libs/vr/libpdx_uds/client_channel_tests.cpp
index 7c3c68a..1560030 100644
--- a/libs/vr/libpdx_uds/client_channel_tests.cpp
+++ b/libs/vr/libpdx_uds/client_channel_tests.cpp
@@ -13,6 +13,7 @@
 #include <pdx/client.h>
 #include <pdx/rpc/remote_method.h>
 #include <pdx/service.h>
+#include <pdx/service_dispatcher.h>
 
 #include <uds/client_channel_factory.h>
 #include <uds/service_endpoint.h>
@@ -81,7 +82,7 @@
     auto endpoint = Endpoint::CreateFromSocketFd(LocalHandle{});
     endpoint->RegisterNewChannelForTests(std::move(channel_socket));
     service_ = TestService::Create(std::move(endpoint));
-    dispatcher_ = android::pdx::uds::ServiceDispatcher::Create();
+    dispatcher_ = ServiceDispatcher::Create();
     dispatcher_->AddService(service_);
     dispatch_thread_ = std::thread(
         std::bind(&ServiceDispatcher::EnterDispatchLoop, dispatcher_.get()));
diff --git a/libs/vr/libpdx_uds/private/uds/service_dispatcher.h b/libs/vr/libpdx_uds/private/uds/service_dispatcher.h
deleted file mode 100644
index 23af4f4..0000000
--- a/libs/vr/libpdx_uds/private/uds/service_dispatcher.h
+++ /dev/null
@@ -1,55 +0,0 @@
-#ifndef ANDROID_PDX_UDS_SERVICE_DISPATCHER_H_
-#define ANDROID_PDX_UDS_SERVICE_DISPATCHER_H_
-
-#include <list>
-#include <memory>
-#include <mutex>
-#include <unordered_map>
-
-#include <pdx/file_handle.h>
-#include <pdx/service_dispatcher.h>
-
-namespace android {
-namespace pdx {
-namespace uds {
-
-class ServiceDispatcher : public pdx::ServiceDispatcher {
- public:
-  // Get a new instance of ServiceDispatcher, or return nullptr if init failed.
-  static std::unique_ptr<pdx::ServiceDispatcher> Create();
-
-  ~ServiceDispatcher() override;
-  int AddService(const std::shared_ptr<Service>& service) override;
-  int RemoveService(const std::shared_ptr<Service>& service) override;
-  int ReceiveAndDispatch() override;
-  int ReceiveAndDispatch(int timeout) override;
-  int EnterDispatchLoop() override;
-  void SetCanceled(bool cancel) override;
-  bool IsCanceled() const override;
-
- private:
-  ServiceDispatcher();
-
-  // Internal thread accounting.
-  int ThreadEnter();
-  void ThreadExit();
-
-  std::mutex mutex_;
-  std::condition_variable condition_;
-  std::atomic<bool> canceled_{false};
-
-  std::list<std::shared_ptr<Service>> services_;
-
-  int thread_count_ = 0;
-  LocalHandle event_fd_;
-  LocalHandle epoll_fd_;
-
-  ServiceDispatcher(const ServiceDispatcher&) = delete;
-  void operator=(const ServiceDispatcher&) = delete;
-};
-
-}  // namespace uds
-}  // namespace pdx
-}  // namespace android
-
-#endif  // ANDROID_PDX_UDS_SERVICE_DISPATCHER_H_
diff --git a/libs/vr/libpdx_uds/private/uds/service_endpoint.h b/libs/vr/libpdx_uds/private/uds/service_endpoint.h
index 368891c..a163812 100644
--- a/libs/vr/libpdx_uds/private/uds/service_endpoint.h
+++ b/libs/vr/libpdx_uds/private/uds/service_endpoint.h
@@ -12,7 +12,6 @@
 #include <pdx/service.h>
 #include <pdx/service_endpoint.h>
 #include <uds/channel_event_set.h>
-#include <uds/service_dispatcher.h>
 
 namespace android {
 namespace pdx {
@@ -105,7 +104,7 @@
   // socket file descriptor.
   Status<void> RegisterNewChannelForTests(LocalHandle channel_fd);
 
-  int epoll_fd() const { return epoll_fd_.Get(); }
+  int epoll_fd() const override { return epoll_fd_.Get(); }
 
  private:
   struct ChannelData {
diff --git a/libs/vr/libpdx_uds/remote_method_tests.cpp b/libs/vr/libpdx_uds/remote_method_tests.cpp
index 3109753..3f25776 100644
--- a/libs/vr/libpdx_uds/remote_method_tests.cpp
+++ b/libs/vr/libpdx_uds/remote_method_tests.cpp
@@ -15,9 +15,9 @@
 #include <pdx/rpc/remote_method.h>
 #include <pdx/rpc/serializable.h>
 #include <pdx/service.h>
+#include <pdx/service_dispatcher.h>
 #include <uds/client_channel.h>
 #include <uds/client_channel_factory.h>
-#include <uds/service_dispatcher.h>
 #include <uds/service_endpoint.h>
 
 using android::pdx::BorrowedHandle;
@@ -561,7 +561,7 @@
 
   void SetUp() override {
     // Create a dispatcher to handle messages to services.
-    dispatcher_ = android::pdx::uds::ServiceDispatcher::Create();
+    dispatcher_ = android::pdx::ServiceDispatcher::Create();
     ASSERT_NE(nullptr, dispatcher_);
 
     // Start the message dispatch loop in a separate thread.
diff --git a/libs/vr/libpdx_uds/service_framework_tests.cpp b/libs/vr/libpdx_uds/service_framework_tests.cpp
index 2943239..5943b0a 100644
--- a/libs/vr/libpdx_uds/service_framework_tests.cpp
+++ b/libs/vr/libpdx_uds/service_framework_tests.cpp
@@ -16,10 +16,10 @@
 #include <pdx/client.h>
 #include <pdx/file_handle.h>
 #include <pdx/service.h>
+#include <pdx/service_dispatcher.h>
 #include <private/android_filesystem_config.h>
 #include <uds/client_channel.h>
 #include <uds/client_channel_factory.h>
-#include <uds/service_dispatcher.h>
 #include <uds/service_endpoint.h>
 
 using android::pdx::BorrowedChannelHandle;
@@ -425,7 +425,7 @@
 
   void SetUp() override {
     // Create a dispatcher to handle messages to services.
-    dispatcher_ = android::pdx::uds::ServiceDispatcher::Create();
+    dispatcher_ = android::pdx::ServiceDispatcher::Create();
     ASSERT_NE(nullptr, dispatcher_);
 
     // Start the message dispatch loop in a separate thread.
diff --git a/libs/vr/libvrflinger/include/dvr/vr_flinger.h b/libs/vr/libvrflinger/include/dvr/vr_flinger.h
index 145852e..6c1995e 100644
--- a/libs/vr/libvrflinger/include/dvr/vr_flinger.h
+++ b/libs/vr/libvrflinger/include/dvr/vr_flinger.h
@@ -4,7 +4,7 @@
 #include <thread>
 #include <memory>
 
-#include <pdx/default_transport/service_dispatcher.h>
+#include <pdx/service_dispatcher.h>
 #include <vr/vr_manager/vr_manager.h>
 
 namespace android {
diff --git a/libs/vr/libvrflinger/vr_flinger.cpp b/libs/vr/libvrflinger/vr_flinger.cpp
index b2dc1d8..41526ee 100644
--- a/libs/vr/libvrflinger/vr_flinger.cpp
+++ b/libs/vr/libvrflinger/vr_flinger.cpp
@@ -18,8 +18,6 @@
 #include <sys/prctl.h>
 #include <sys/resource.h>
 
-#include <pdx/default_transport/service_dispatcher.h>
-
 #include <functional>
 
 #include "DisplayHardware/ComposerHal.h"
@@ -76,7 +74,7 @@
 
   request_display_callback_ = request_display_callback;
 
-  dispatcher_ = android::pdx::default_transport::ServiceDispatcher::Create();
+  dispatcher_ = android::pdx::ServiceDispatcher::Create();
   CHECK_ERROR(!dispatcher_, error, "Failed to create service dispatcher.");
 
   display_service_ =