FSCORE-612 with mods

src/include/private/switch_core_pvt.h

@@ -195,7 +195,7 @@ struct switch_runtime {
 	switch_time_t initiated;
 	switch_time_t reference;
 	int64_t offset;
-	switch_hash_t *global_vars;
+	switch_event_t *global_vars;
 	switch_hash_t *mime_types;
 	switch_memory_pool_t *memory_pool;
 	const switch_state_handler_table_t *state_handlers[SWITCH_MAX_STATE_HANDLERS];

src/include/switch_core.h

@@ -750,6 +750,17 @@ SWITCH_DECLARE(char *) switch_core_get_variable(_In_z_ const char *varname);
 */
 SWITCH_DECLARE(void) switch_core_set_variable(_In_z_ const char *varname, _In_opt_z_ const char *value);
 
+/*! 
+  \brief Conditionally add a global variable to the core
+  \param varname the name of the variable
+  \param value the value of the variable
+  \param val2 the value of the variable to verify against
+  \     If the global did not exist and val2=="", add global with value, return true
+  \     If the global exists with the value of val2, replace it, return true
+  \     If the global exists with a value other than val2, return false
+*/
+SWITCH_DECLARE(switch_bool_t) switch_core_set_var_conditional(_In_z_ const char *varname, _In_opt_z_ const char *value, _In_opt_z_ const char *val2);
+
 SWITCH_DECLARE(void) switch_core_dump_variables(_In_ switch_stream_handle_t *stream);
 
 /*! 

src/include/switch_types.h

@@ -754,8 +754,9 @@ SWITCH_STACK_TOP	- Stack on the top
 </pre>
  */
 typedef enum {
-	SWITCH_STACK_BOTTOM,
-	SWITCH_STACK_TOP
+	SWITCH_STACK_BOTTOM = (1 << 0),
+	SWITCH_STACK_TOP = (1 << 1),
+	SWITCH_STACK_NODUP = (1 << 2)
 } switch_stack_t;
 
 /*!