Add global memory context to PL/Python

Author: Nikita Glukhov

src/pl/plpython/plpy_main.c

@@ -73,6 +73,7 @@ PyObject   *PLy_interp_globals = NULL;
 /* this doesn't need to be global; use PLy_current_execution_context() */
 static PLyExecutionContext *PLy_execution_contexts = NULL;
 
+static MemoryContext PLy_memory_context;
 
 void
 _PG_init(void)
@@ -464,3 +465,14 @@ PLy_pop_execution_context(void)
 		MemoryContextDelete(context->scratch_ctx);
 	pfree(context);
 }
+
+MemoryContext
+PLy_get_global_memory_context(void)
+{
+	if (!PLy_memory_context)
+		PLy_memory_context = AllocSetContextCreate(TopMemoryContext,
+												   "PL/Python global context",
+													ALLOCSET_DEFAULT_SIZES);
+
+	return PLy_memory_context;
+}

src/pl/plpython/plpy_main.h

@@ -28,4 +28,7 @@ extern PLyExecutionContext *PLy_current_execution_context(void);
 /* Get the scratch memory context for specified execution context */
 extern MemoryContext PLy_get_scratch_context(PLyExecutionContext *context);
 
+/* Get the global memory context */
+extern MemoryContext PLy_get_global_memory_context(void);
+
 #endif							/* PLPY_MAIN_H */