[SafeReference] Move safe_reference from database to app so other packages can use it.

Tested with database desktop_testapp

PiperOrigin-RevId: 243640110

Author: cynthiajiang

database/src/desktop/connection/safe_reference.h renamed to app/src/safe_reference.h

@@ -12,16 +12,20 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#ifndef FIREBASE_DATABASE_CLIENT_CPP_SRC_DESKTOP_CONNECTION_SAFE_REFERENCE_H_
-#define FIREBASE_DATABASE_CLIENT_CPP_SRC_DESKTOP_CONNECTION_SAFE_REFERENCE_H_
+#ifndef FIREBASE_APP_CLIENT_CPP_SRC_SAFE_REFERENCE_H_
+#define FIREBASE_APP_CLIENT_CPP_SRC_SAFE_REFERENCE_H_
 
 #include "app/memory/shared_ptr.h"
 #include "app/src/mutex.h"
 
-namespace firebase {
-namespace database {
+#if !defined(FIREBASE_NAMESPACE)
+#define FIREBASE_NAMESPACE firebase
+#endif
+
+namespace FIREBASE_NAMESPACE {
 namespace internal {
-namespace connection {
+
+// TODO(b/130544650): Add unit test to this file.
 
 // SafeReference owns a pointers to an object which can be deleted in anytime.
 // SafeReference can be shared to different thread that potentially have longer
@@ -72,9 +76,8 @@ class SafeReferenceLock {
   SafeReference<T>* ref_;
   MutexLock lock_;
 };
-}  // namespace connection
+
 }  // namespace internal
-}  // namespace database
-}  // namespace firebase
+}  // namespace FIREBASE_NAMESPACE
 
-#endif  // FIREBASE_DATABASE_CLIENT_CPP_SRC_DESKTOP_CONNECTION_SAFE_REFERENCE_H_
+#endif  // FIREBASE_APP_CLIENT_CPP_SRC_SAFE_REFERENCE_H_

database/src/desktop/connection/connection.h

@@ -20,9 +20,9 @@
 #include "app/memory/atomic.h"
 #include "app/memory/unique_ptr.h"
 #include "app/src/include/firebase/variant.h"
+#include "app/src/safe_reference.h"
 #include "app/src/scheduler.h"
 #include "database/src/desktop/connection/host_info.h"
-#include "database/src/desktop/connection/safe_reference.h"
 #include "database/src/desktop/connection/web_socket_client_interface.h"
 
 namespace firebase {
@@ -175,8 +175,8 @@ class Connection : public WebSocketClientEventHandler {
   // Safe reference to this.  Set in constructor and cleared in destructor
   // Should be safe to be copied in any thread because the SharedPtr never
   // changes, until safe_this_ is completely destroyed.
-  typedef SafeReference<Connection> ConnectionRef;
-  typedef SafeReferenceLock<Connection> ConnectionRefLock;
+  typedef firebase::internal::SafeReference<Connection> ConnectionRef;
+  typedef firebase::internal::SafeReferenceLock<Connection> ConnectionRefLock;
   ConnectionRef safe_this_;
 
   // Event handler for higher level

database/src/desktop/connection/persistent_connection.h

@@ -29,11 +29,11 @@
 #include "app/src/include/firebase/variant.h"
 #include "app/src/optional.h"
 #include "app/src/path.h"
+#include "app/src/safe_reference.h"
 #include "app/src/scheduler.h"
 #include "database/src/common/query_spec.h"
 #include "database/src/desktop/connection/connection.h"
 #include "database/src/desktop/connection/host_info.h"
-#include "database/src/desktop/connection/safe_reference.h"
 #include "database/src/include/firebase/database/common.h"
 
 namespace firebase {
@@ -465,8 +465,9 @@ class PersistentConnection : public ConnectionEventHandler {
   // Safe reference to this.  Set in constructor and cleared in destructor
   // Should be safe to be copied in any thread because the SharedPtr never
   // changes, until safe_this_ is completely destroyed.
-  typedef SafeReference<PersistentConnection> ThisRef;
-  typedef SafeReferenceLock<PersistentConnection> ThisRefLock;
+  typedef firebase::internal::SafeReference<PersistentConnection> ThisRef;
+  typedef firebase::internal::SafeReferenceLock<PersistentConnection>
+      ThisRefLock;
   ThisRef safe_this_;
 
   // Scheduler to make sure all Connection events are handled in worker

database/src/desktop/core/repo.h

@@ -16,12 +16,13 @@
 #define FIREBASE_DATABASE_CLIENT_CPP_SRC_DESKTOP_CORE_REPO_H_
 
 #include <vector>
+
 #include "app/memory/unique_ptr.h"
 #include "app/src/include/firebase/variant.h"
 #include "app/src/path.h"
 #include "app/src/reference_counted_future_impl.h"
+#include "app/src/safe_reference.h"
 #include "database/src/desktop/connection/persistent_connection.h"
-#include "database/src/desktop/connection/safe_reference.h"
 #include "database/src/desktop/core/event_registration.h"
 #include "database/src/desktop/core/sparse_snapshot_tree.h"
 #include "database/src/desktop/core/sync_tree.h"
@@ -40,8 +41,8 @@ class EventRegistration;
 
 class Repo : public connection::PersistentConnectionEventHandler {
  public:
-  typedef connection::SafeReference<Repo> ThisRef;
-  typedef connection::SafeReferenceLock<Repo> ThisRefLock;
+  typedef firebase::internal::SafeReference<Repo> ThisRef;
+  typedef firebase::internal::SafeReferenceLock<Repo> ThisRefLock;
 
   explicit Repo(App* app, DatabaseInternal* database, const char* url);
 

database/src/desktop/database_desktop.h

@@ -17,16 +17,17 @@
 
 #include <list>
 #include <string>
+
 #include "app/src/cleanup_notifier.h"
 #include "app/src/future_manager.h"
 #include "app/src/include/firebase/app.h"
 #include "app/src/mutex.h"
+#include "app/src/safe_reference.h"
 #include "app/src/scheduler.h"
 #include "database/src/common/listener.h"
 #include "database/src/common/query_spec.h"
 #include "database/src/desktop/connection/host_info.h"
 #include "database/src/desktop/connection/persistent_connection.h"
-#include "database/src/desktop/connection/safe_reference.h"
 #include "database/src/desktop/core/indexed_variant.h"
 #include "database/src/desktop/core/repo.h"
 #include "database/src/desktop/push_child_name_generator.h"
@@ -144,8 +145,8 @@ class DatabaseInternal {
     }
   }
 
-  typedef connection::SafeReference<DatabaseInternal> ThisRef;
-  typedef connection::SafeReferenceLock<DatabaseInternal> ThisRefLock;
+  typedef firebase::internal::SafeReference<DatabaseInternal> ThisRef;
+  typedef firebase::internal::SafeReferenceLock<DatabaseInternal> ThisRefLock;
 
   // Call from transaction response to handle the response result.
   void HandleTransactionResponse(const connection::ResponsePtr& ptr);