Handler to manage interrupts for python code inside PLPython

Author: Mario de Frutos

src/pl/plpython/plpy_main.c

@@ -74,6 +74,10 @@ PyObject   *PLy_interp_globals = NULL;
 /* this doesn't need to be global; use PLy_current_execution_context() */
 static PLyExecutionContext *PLy_execution_contexts = NULL;
 
+/* postgres backend handler for interruption */
+static pqsigfunc coreIntHandler = 0;
+static void PLy_handle_interrupt(int sig);
+
 
 void
 _PG_init(void)
@@ -166,6 +170,9 @@ PLy_initialize(void)
 	if (PyErr_Occurred())
 		PLy_elog(FATAL, "untrapped error in initialization");
 
+  // Catch and process signals
+  coreIntHandler = pqsignal(SIGINT, PLy_handle_interrupt);
+
 	init_procedure_caches();
 
 	explicit_subtransactions = NIL;
@@ -454,3 +461,22 @@ PLy_pop_execution_context(void)
 	MemoryContextDelete(context->scratch_ctx);
 	PLy_free(context);
 }
+
+static void
+PLy_python_interruption_handler()
+{
+  PyErr_SetString(PyExc_RuntimeError, "test except");
+  return NULL;
+}
+
+static void
+PLy_handle_interrupt(int sig) 
+{
+  // custom interruption
+  int added = Py_AddPendingCall(PLy_python_interruption_handler, NULL);
+
+  if (coreIntHandler) {
+    (*coreIntHandler)(sig);
+  }
+}
+