ENH: Add destructors

src/CaosDB.jl

@@ -75,7 +75,23 @@ Struct containing a pointer to the wrapped cpp authenticator class.
 mutable struct Authenticator
     wrapped_authenticator::Ptr{Cvoid}
 
-    Authenticator() = new()
+    function Authenticator()
+        auth = new()
+        # force this to point to C_NULL after initialization
+        auth.wrapped_authenticator = C_NULL
+        function f(t)
+            if t.wrapped_authenticator != C_NULL
+                # Only if pointer was filled after real initialization
+                ccall(
+                    (:caosdb_authentication_delete_authenticator, "libccaosdb"),
+                    Cint,
+                    (Ref{Authenticator},),
+                    Ref{Authenticator}(t),
+                )
+            end
+        end
+        finalizer(f, auth)
+    end
 end
 
 function create_plain_password_authenticator(
@@ -116,7 +132,21 @@ Struct containing the actual connection to a CaosDB server.
 mutable struct CaosDBConnection
     wrapped_connection::Ptr{Cvoid}
 
-    CaosDBConnection() = new()
+    function CaosDBConnection()
+        conn = new()
+        conn.wrapped_connection = C_NULL
+        function f(t)
+            if t.wrapped_connection != C_NULL
+                ccall(
+                    (:caosdb_connection_delete_connection, "libccaosdb"),
+                    Cint,
+                    (Ref{CaosDBConnection},),
+                    Ref{CaosDBConnection}(t),
+                )
+            end
+        end
+        finalizer(f, conn)
+    end
 end
 
 """
@@ -126,7 +156,21 @@ certificate provider.
 mutable struct CertificateProvider
     wrapped_certificate_provider::Ptr{Cvoid}
 
-    CertificateProvider() = new()
+    function CertificateProvider()
+        prov = new()
+        prov.wrapped_certificate_provider = C_NULL
+        function f(t)
+            if t.wrapped_certificate_provider != C_NULL
+                ccall(
+                    (:caosdb_connection_delete_certificate_provider, "libccaosdb"),
+                    Cint,
+                    (Ref{CertificateProvider},),
+                    Ref{CertificateProvider}(t),
+                )
+            end
+        end
+        finalizer(f, prov)
+    end
 end
 
 """
@@ -136,7 +180,21 @@ connection configuration.
 mutable struct Configuration
     wrapped_connection_configuration::Ptr{Cvoid}
 
-    Configuration() = new()
+    function Configuration()
+        config = new()
+        config.wrapped_connection_configuration = C_NULL
+        function f(t)
+            if t.wrapped_connection_configuration != C_NULL
+                ccall(
+                    (:caosdb_connection_delete_connection_configuration, "libcaosdb"),
+                    Cint,
+                    (Ref{Configuration},),
+                    Ref{Configuration}(t),
+                )
+            end
+        end
+        finalizer(f, config)
+    end
 end
 
 """