WIP: Issue #5218 - Verify dependencies between PR #5217 (PROXYSQL STOP/START crash fixes) and PR #4960 (module enable/disable)

include/PgSQL_Thread.h

@@ -1050,10 +1050,10 @@ class PgSQL_Threads_Handler
 		bool query_cache_stores_empty_result;
 		bool kill_backend_connection_when_disconnect;
 		bool client_session_track_gtid;
-		bool enable_client_deprecate_eof;
-		bool enable_server_deprecate_eof;
-		bool enable_load_data_local_infile;
-		bool log_mysql_warnings_enabled;
+		//bool enable_client_deprecate_eof;
+		//bool enable_server_deprecate_eof;
+		//bool enable_load_data_local_infile;
+		//bool log_mysql_warnings_enabled;
 		int data_packets_history_size;
 		int handle_warnings;
 		char* server_version;

include/proxysql_glovars.hpp

@@ -87,8 +87,50 @@ class ProxySQL_GlobalVariables {
 		unsigned long long start_time;
 		bool gdbg;
 		bool nostart;
+		/**
+		 * @brief Disable/Enable the MySQL Monitor module.
+		 * @details Meant to be configured as an startup switch. Possible to change it's value only via a
+		 *  command line switch or via config file option.
+		 */
 		bool my_monitor;
+		/**
+		 * @brief Disable/Enable the PostgreSQL Monitor module.
+		 * @details Meant to be configured as an startup switch. Possible to change it's value only via a
+		 *  command line switch or via config file option.
+		 */
 		bool pg_monitor;
+		/**
+		 * @brief Disable/Enable the MySQL Workers module. This disables ProxySQL capability for handling
+		 *  MySQL traffic to be routed to the MySQL backend servers.
+		 * @details Meant to be configured as an startup switch. Possible to change it's value only via a
+		 *  command line switch or via config file option. Disabling this module doesn't affect MySQL
+		 *  Monitoring.
+		 */
+		bool mysql_workers;
+		/**
+		 * @brief Disable/Enable the PostgreSQL Workers module. This disables ProxySQL capability for handling
+		 *  PostgreSQL traffic to be routed to the PostgreSQL backend servers.
+		 * @details Meant to be configured as an startup switch. Possible to change it's value only via a
+		 *  command line switch or via config file option. Disabling this module doesn't affect PostgreSQL
+		 *  Monitoring.
+		 */
+		bool pgsql_workers;
+		/**
+		 * @brief Disable/Enable MySQL Admin module. This disables access, via MySQL protocol, to
+		 *  ProxySQL Administration interface.
+		 * @details Meant to be configured as an startup switch. Possible to change it's value only via a
+		 *  command line switch or via config file option. It's important to notice that Administrative access
+		 *  remains possible via PostgreSQL Admin interface, if enabled.
+		 */
+		bool mysql_admin;
+		/**
+		 * @brief Disable/Enable PostgreSQL Admin module. This disables access, via PostgreSQL
+		 *  protocol, to ProxySQL Administration interface.
+		 * @details Meant to be configured as an startup switch. Possible to change it's value only via a
+		 *  command line switch or via config file option. It's important to notice that Administrative access
+		 *  remains possible via the MySQL Admin interface, if enabled.
+		 */
+		bool pgsql_admin;
 		bool version_check;
 #ifdef SO_REUSEPORT
 		bool reuseport;

include/proxysql_structs.h

@@ -758,6 +758,14 @@ enum proxysql_session_type {
 	PROXYSQL_SESSION_NONE
 };
 
+// Stop state enumeration for PROXYSQL STOP command (issue 5186)
+// Used to manage admin query access during module stop/start cycle
+enum proxy_stop_state {
+	STOP_STATE_RUNNING = 0,	// Normal operation, all modules running
+	STOP_STATE_DRAINING = 1,	// Admin queries being drained, modules stopping
+	STOP_STATE_STOPPED = 2	// Modules stopped, only safe queries allowed
+};
+
 #endif /* PROXYSQL_ENUMS */
 
 
@@ -959,6 +967,11 @@ struct _global_variables_t {
 	bool nostart;
 	int reload;
 
+	// Stop state management for PROXYSQL STOP command
+	// See issue 5186: Fix query handling after PROXYSQL STOP
+	volatile int stop_state;
+	uint64_t active_admin_queries;
+
 	unsigned char protocol_version;
 	char *mysql_server_version;
 	uint32_t server_capabilities;