Factor out loading & running of DSOs

mojo/shell/in_process_dynamic_service_runner.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/shell/in_process_dynamic_service_runner.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/location.h"
-#include "base/logging.h"
 #include "base/message_loop/message_loop_proxy.h"
-#include "mojo/public/platform/native/gles2_impl_chromium_sync_point_thunks.h"
-#include "mojo/public/platform/native/gles2_impl_chromium_texture_mailbox_thunks.h"
-#include "mojo/public/platform/native/gles2_impl_thunks.h"
-#include "mojo/public/platform/native/gles2_thunks.h"
-#include "mojo/public/platform/native/system_thunks.h"
 
 namespace mojo {
 namespace shell {
 
-namespace {
-
-template <typename Thunks>
-bool SetThunks(Thunks (*make_thunks)(),
-               const char* function_name,
-               base::ScopedNativeLibrary* library) {
-  typedef size_t (*SetThunksFn)(const Thunks* thunks);
-  SetThunksFn set_thunks =
-      reinterpret_cast<SetThunksFn>(library->GetFunctionPointer(function_name));
-  if (!set_thunks)
-    return false;
-  Thunks thunks = make_thunks();
-  size_t expected_size = set_thunks(&thunks);
-  if (expected_size > sizeof(Thunks)) {
-    LOG(ERROR) << "Invalid app library: expected " << function_name
-               << " to return thunks of size: " << expected_size;
-    return false;
-  }
-  return true;
-}
-}
-
 InProcessDynamicServiceRunner::InProcessDynamicServiceRunner(
-    Context* context) {
+    Context* context) : app_library_(nullptr) {
 }
 
 InProcessDynamicServiceRunner::~InProcessDynamicServiceRunner() {
   if (thread_) {
     DCHECK(thread_->HasBeenStarted());
     DCHECK(!thread_->HasBeenJoined());
     thread_->Join();
   }
 
   // It is important to let the thread exit before unloading the DSO because
   // the library may have registered thread-local data and destructors to run
   // on thread termination.
-  app_library_.Reset(base::NativeLibrary());
+  if (app_library_)
+    base::UnloadNativeLibrary(app_library_);
 }
 
 void InProcessDynamicServiceRunner::Start(
     const base::FilePath& app_path,
     ScopedMessagePipeHandle service_handle,
     const base::Closure& app_completed_callback) {
   app_path_ = app_path;
 
   DCHECK(!service_handle_.is_valid());
   service_handle_ = service_handle.Pass();
 
   DCHECK(app_completed_callback_runner_.is_null());
   app_completed_callback_runner_ = base::Bind(&base::TaskRunner::PostTask,
                                               base::MessageLoopProxy::current(),
                                               FROM_HERE,
                                               app_completed_callback);
 
   DCHECK(!thread_);
   thread_.reset(new base::DelegateSimpleThread(this, "app_thread"));
   thread_->Start();
 }
 
 void InProcessDynamicServiceRunner::Run() {
   DVLOG(2) << "Loading/running Mojo app in process from library: "
            << app_path_.value();
 
-  do {
-    base::NativeLibraryLoadError error;
-    app_library_.Reset(base::LoadNativeLibrary(app_path_, &error));
-    if (!app_library_.is_valid()) {
-      LOG(ERROR) << "Failed to load app library (error: " << error.ToString()
-                 << ")";
-      break;
-    }
-    // Go shared library support requires us to initialize the runtime before we
-    // start running any go code. This is a temporary patch.
-    typedef void (*InitGoRuntimeFn)();
-    InitGoRuntimeFn runtime = reinterpret_cast<InitGoRuntimeFn>(
-        app_library_.GetFunctionPointer("InitGoRuntime"));
-    if (runtime) {
-      DVLOG(2) << "InitGoRuntime: Initializing Go Runtime found in app";
-      runtime();
-    }
-    if (!SetThunks(
-            &MojoMakeSystemThunks, "MojoSetSystemThunks", &app_library_)) {
-      // In the component build, Mojo Apps link against mojo_system_impl.
-#if !defined(COMPONENT_BUILD)
-      // Strictly speaking this is not required, but it's very unusual to have
-      // an app that doesn't require the basic system library.
-      LOG(WARNING) << "MojoSetSystemThunks not found in app library";
-#endif
-    }
-
-    if (SetThunks(&MojoMakeGLES2ControlThunks,
-                  "MojoSetGLES2ControlThunks",
-                  &app_library_)) {
-      // If we have the control thunks, we probably also have the
-      // GLES2 implementation thunks.
-      if (!SetThunks(&MojoMakeGLES2ImplThunks,
-                     "MojoSetGLES2ImplThunks",
-                     &app_library_)) {
-        // In the component build, Mojo Apps link against mojo_gles2_impl.
-#if !defined(COMPONENT_BUILD)
-        // Warn on this really weird case: The library requires the GLES2
-        // control functions, but doesn't require the GLES2 implementation.
-        LOG(WARNING) << app_path_.value()
-                     << " has MojoSetGLES2ControlThunks, "
-                        "but doesn't have MojoSetGLES2ImplThunks.";
-#endif
-      }
-
-      // If the application is using GLES2 extension points, register those
-      // thunks. Applications may use or not use any of these, so don't warn if
-      // they are missing.
-      SetThunks(MojoMakeGLES2ImplChromiumTextureMailboxThunks,
-                "MojoSetGLES2ImplChromiumTextureMailboxThunks",
-                &app_library_);
-      SetThunks(MojoMakeGLES2ImplChromiumSyncPointThunks,
-                "MojoSetGLES2ImplChromiumSyncPointThunks",
-                &app_library_);
-    }
-    // Unlike system thunks, we don't warn on a lack of GLES2 thunks because
-    // not everything is a visual app.
-
-    typedef MojoResult (*MojoMainFunction)(MojoHandle);
-    MojoMainFunction main_function = reinterpret_cast<MojoMainFunction>(
-        app_library_.GetFunctionPointer("MojoMain"));
-    if (!main_function) {
-      LOG(ERROR) << "Entrypoint MojoMain not found: " << app_path_.value();
-      break;
-    }
-
-    // |MojoMain()| takes ownership of the service handle.
-    MojoResult result = main_function(service_handle_.release().value());
-    if (result < MOJO_RESULT_OK)
-      LOG(ERROR) << "MojoMain returned an error: " << result;
-  } while (false);
-
+  app_library_ = LoadAndRunService(app_path_, service_handle_.Pass());
   app_completed_callback_runner_.Run();
   app_completed_callback_runner_.Reset();
 }
 
 }  // namespace shell
 }  // namespace mojo