Part1: MDEV-20837 Add MariaDB_FUNCTION_PLUGIN

- Defining MariaDB_FUNCTION_PLUGIN
- Changing the code in /plugins/type_inet/ and /plugins/type_test/
  to use MariaDB_FUNCTION_PLUGIN instead of MariaDB_FUNCTION_COLLECTION_PLUGIN.
- Changing maturity for the INET6 data type plugin from experimental to alpha.

cmake/abi_check.cmake

@@ -46,6 +46,7 @@ IF(CMAKE_C_COMPILER_ID MATCHES "GNU|Clang" AND RUN_ABI_CHECK)
     ${CMAKE_SOURCE_DIR}/include/mysql/plugin_password_validation.h
     ${CMAKE_SOURCE_DIR}/include/mysql/plugin_encryption.h
     ${CMAKE_SOURCE_DIR}/include/mysql/plugin_data_type.h
+    ${CMAKE_SOURCE_DIR}/include/mysql/plugin_function.h
     ${CMAKE_SOURCE_DIR}/include/mysql/plugin_function_collection.h
   )
 

include/mysql/plugin.h

@@ -90,13 +90,14 @@ typedef struct st_mysql_xid MYSQL_XID;
 #define MYSQL_AUDIT_PLUGIN           5
 #define MYSQL_REPLICATION_PLUGIN     6
 #define MYSQL_AUTHENTICATION_PLUGIN  7
-#define MYSQL_MAX_PLUGIN_TYPE_NUM    12  /* The number of plugin types   */
+#define MYSQL_MAX_PLUGIN_TYPE_NUM    13  /* The number of plugin types   */
 
 /* MariaDB plugin types */
 #define MariaDB_PASSWORD_VALIDATION_PLUGIN  8
 #define MariaDB_ENCRYPTION_PLUGIN 9
 #define MariaDB_DATA_TYPE_PLUGIN  10
-#define MariaDB_FUNCTION_COLLECTION_PLUGIN 11
+#define MariaDB_FUNCTION_PLUGIN 11
+#define MariaDB_FUNCTION_COLLECTION_PLUGIN 12
 
 /* We use the following strings to define licenses for plugins */
 #define PLUGIN_LICENSE_PROPRIETARY 0

include/mysql/plugin_function.h

+#ifndef MARIADB_PLUGIN_FUNCTION_INCLUDED
+#define MARIADB_PLUGIN_FUNCTION_INCLUDED
+/* Copyright (C) 2019, Alexander Barkov and MariaDB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+/**
+  @file
+
+  Function Plugin API.
+
+  This file defines the API for server plugins that manage functions.
+*/
+
+#ifdef __cplusplus
+
+#include <mysql/plugin.h>
+
+/*
+  API for function plugins. (MariaDB_FUNCTION_PLUGIN)
+*/
+#define MariaDB_FUNCTION_INTERFACE_VERSION (MYSQL_VERSION_ID << 8)
+
+
+class Plugin_function
+{
+  int m_interface_version;
+  Create_func *m_builder;
+public:
+  Plugin_function(Create_func *builder)
+   :m_interface_version(MariaDB_FUNCTION_INTERFACE_VERSION),
+    m_builder(builder)
+  { }
+  Create_func *create_func()
+  {
+    return m_builder;
+  }
+};
+
+
+#endif /* __cplusplus */
+
+#endif /* MARIADB_PLUGIN_FUNCTION_INCLUDED */

plugin/func_test/mysql-test/func_test/func_test.result

@@ -9,14 +9,14 @@ PLUGIN_LICENSE,
 PLUGIN_MATURITY,
 PLUGIN_AUTH_VERSION
 FROM INFORMATION_SCHEMA.PLUGINS
-WHERE PLUGIN_TYPE='FUNCTION COLLECTION'
-    AND PLUGIN_NAME='func_test';
-PLUGIN_NAME	func_test
+WHERE PLUGIN_TYPE='FUNCTION'
+  AND PLUGIN_NAME='sysconst_test';
+PLUGIN_NAME	sysconst_test
 PLUGIN_VERSION	1.0
 PLUGIN_STATUS	ACTIVE
-PLUGIN_TYPE	FUNCTION COLLECTION
+PLUGIN_TYPE	FUNCTION
 PLUGIN_AUTHOR	MariaDB Corporation
-PLUGIN_DESCRIPTION	Function collection test
+PLUGIN_DESCRIPTION	Function SYSCONST_TEST()
 PLUGIN_LICENSE	GPL
 PLUGIN_MATURITY	Experimental
 PLUGIN_AUTH_VERSION	1.0

plugin/func_test/mysql-test/func_test/func_test.test

@@ -14,8 +14,8 @@ SELECT
   PLUGIN_MATURITY,
   PLUGIN_AUTH_VERSION
 FROM INFORMATION_SCHEMA.PLUGINS
-  WHERE PLUGIN_TYPE='FUNCTION COLLECTION'
-    AND PLUGIN_NAME='func_test';
+WHERE PLUGIN_TYPE='FUNCTION'
+  AND PLUGIN_NAME='sysconst_test';
 --horizontal_results
 
 

plugin/func_test/plugin.cc

@@ -19,7 +19,7 @@
 
 #include <my_global.h>
 #include <sql_class.h>
-#include <mysql/plugin_function_collection.h>
+#include <mysql/plugin_function.h>
 
 class Item_func_sysconst_test :public Item_func_sysconst
 {
@@ -64,26 +64,18 @@ Item* Create_func_sysconst_test::create_builder(THD *thd)
 #define BUILDER(F) & F::s_singleton
 
 
-static Native_func_registry func_array[] =
-{
-  {{STRING_WITH_LEN("SYSCONST_TEST")}, BUILDER(Create_func_sysconst_test)}
-};
-
-
-static Plugin_function_collection
-  plugin_descriptor_function_collection_test(
-    MariaDB_FUNCTION_COLLECTION_INTERFACE_VERSION,
-    Native_func_registry_array(func_array, array_elements(func_array)));
+static Plugin_function
+  plugin_descriptor_function_sysconst_test(BUILDER(Create_func_sysconst_test));
 
 /*************************************************************************/
 
 maria_declare_plugin(type_test)
 {
-  MariaDB_FUNCTION_COLLECTION_PLUGIN, // the plugin type (see include/mysql/plugin.h)
-  &plugin_descriptor_function_collection_test, // pointer to type-specific plugin descriptor
-  "func_test",                  // plugin name
+  MariaDB_FUNCTION_PLUGIN,       // the plugin type (see include/mysql/plugin.h)
+  &plugin_descriptor_function_sysconst_test, // pointer to type-specific plugin descriptor
+  "sysconst_test",              // plugin name
   "MariaDB Corporation",        // plugin author
-  "Function collection test",   // the plugin description
+  "Function SYSCONST_TEST()",   // the plugin description
   PLUGIN_LICENSE_GPL,           // the plugin license (see include/mysql/plugin.h)
   0,                            // Pointer to plugin initialization function
   0,                            // Pointer to plugin deinitialization function

plugin/type_inet/mysql-test/type_inet/func_inet_plugin.result

@@ -5,6 +5,7 @@
 # MDEV-20768 Turn INET functions into a function collection plugin
 #
 SELECT
+'----' AS `----`,
 PLUGIN_NAME,
 PLUGIN_VERSION,
 PLUGIN_STATUS,
@@ -15,16 +16,96 @@ PLUGIN_LICENSE,
 PLUGIN_MATURITY,
 PLUGIN_AUTH_VERSION
 FROM INFORMATION_SCHEMA.PLUGINS
-WHERE PLUGIN_TYPE='FUNCTION COLLECTION'
-    AND PLUGIN_NAME='func_inet';
-PLUGIN_NAME	func_inet
+WHERE PLUGIN_TYPE='FUNCTION'
+  AND PLUGIN_NAME IN
+('inet_aton',
+'inet_ntoa',
+'inet6_aton',
+'inet6_ntoa',
+'is_ipv4',
+'is_ipv6',
+'is_ipv4_compat',
+'is_ipv4_mapped')
+ORDER BY PLUGIN_NAME;
+----	----
+PLUGIN_NAME	inet6_aton
 PLUGIN_VERSION	1.0
 PLUGIN_STATUS	ACTIVE
-PLUGIN_TYPE	FUNCTION COLLECTION
+PLUGIN_TYPE	FUNCTION
 PLUGIN_AUTHOR	MariaDB Corporation
-PLUGIN_DESCRIPTION	Function collection test
+PLUGIN_DESCRIPTION	Function INET6_ATON()
 PLUGIN_LICENSE	GPL
-PLUGIN_MATURITY	Experimental
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	inet6_ntoa
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function INET6_NTOA()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	inet_aton
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function INET_ATON()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	inet_ntoa
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function INET_NTOA()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	is_ipv4
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function IS_IPV4()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	is_ipv4_compat
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function IS_IPV4_COMPAT()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	is_ipv4_mapped
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function IS_IPV4_MAPPED()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
+PLUGIN_AUTH_VERSION	1.0
+----	----
+PLUGIN_NAME	is_ipv6
+PLUGIN_VERSION	1.0
+PLUGIN_STATUS	ACTIVE
+PLUGIN_TYPE	FUNCTION
+PLUGIN_AUTHOR	MariaDB Corporation
+PLUGIN_DESCRIPTION	Function IS_IPV6()
+PLUGIN_LICENSE	GPL
+PLUGIN_MATURITY	Alpha
 PLUGIN_AUTH_VERSION	1.0
 #
 # End of 10.5 tests

plugin/type_inet/mysql-test/type_inet/func_inet_plugin.test

@@ -8,6 +8,7 @@
 
 --vertical_results
 SELECT
+  '----' AS `----`,
   PLUGIN_NAME,
   PLUGIN_VERSION,
   PLUGIN_STATUS,
@@ -18,8 +19,17 @@ SELECT
   PLUGIN_MATURITY,
   PLUGIN_AUTH_VERSION
 FROM INFORMATION_SCHEMA.PLUGINS
-  WHERE PLUGIN_TYPE='FUNCTION COLLECTION'
-    AND PLUGIN_NAME='func_inet';
+WHERE PLUGIN_TYPE='FUNCTION'
+  AND PLUGIN_NAME IN
+    ('inet_aton',
+     'inet_ntoa',
+     'inet6_aton',
+     'inet6_ntoa',
+     'is_ipv4',
+     'is_ipv6',
+     'is_ipv4_compat',
+     'is_ipv4_mapped')
+ORDER BY PLUGIN_NAME;
 --horizontal_results
 
 --echo #

plugin/type_inet/mysql-test/type_inet/type_inet6_plugin.result

@@ -22,9 +22,9 @@ PLUGIN_VERSION	1.0
 PLUGIN_STATUS	ACTIVE
 PLUGIN_TYPE	DATA TYPE
 PLUGIN_AUTHOR	MariaDB Corporation
-PLUGIN_DESCRIPTION	Data type TEST_INT8
+PLUGIN_DESCRIPTION	Data type INET6
 PLUGIN_LICENSE	GPL
-PLUGIN_MATURITY	Experimental
+PLUGIN_MATURITY	Alpha
 PLUGIN_AUTH_VERSION	1.0
 #
 # End of 10.5 tests

sql/item_create.cc

@@ -35,6 +35,7 @@
 #include "sp.h"
 #include "sql_time.h"
 #include "sql_type_geom.h"
+#include <mysql/plugin_function.h>
 #include <mysql/plugin_function_collection.h>
 
 
@@ -5710,6 +5711,24 @@ void item_create_cleanup()
   DBUG_VOID_RETURN;
 }
 
+
+static Create_func *
+function_plugin_find_native_function_builder(THD *thd, const LEX_CSTRING &name)
+{
+  plugin_ref plugin;
+  if ((plugin= my_plugin_lock_by_name(thd, &name, MariaDB_FUNCTION_PLUGIN)))
+  {
+    Create_func *builder=
+      reinterpret_cast<Plugin_function*>(plugin_decl(plugin)->info)->
+        create_func();
+    // TODO: MDEV-20846 Add proper unlocking for MariaDB_FUNCTION_PLUGIN
+    plugin_unlock(thd, plugin);
+    return builder;
+  }
+  return NULL;
+}
+
+
 Create_func *
 find_native_function_builder(THD *thd, const LEX_CSTRING *name)
 {
@@ -5724,6 +5743,9 @@ find_native_function_builder(THD *thd, const LEX_CSTRING *name)
   if (func && (builder= func->builder))
     return builder;
 
+  if ((builder= function_plugin_find_native_function_builder(thd, *name)))
+    return builder;
+
   if ((builder= Plugin_find_native_func_builder_param(*name).find(thd)))
     return builder;
 

sql/sql_plugin.cc

@@ -39,6 +39,7 @@
 #include <mysql/plugin_password_validation.h>
 #include <mysql/plugin_encryption.h>
 #include <mysql/plugin_data_type.h>
+#include <mysql/plugin_function.h>
 #include <mysql/plugin_function_collection.h>
 #include "sql_plugin_compat.h"
 
@@ -94,6 +95,7 @@ const LEX_CSTRING plugin_type_names[MYSQL_MAX_PLUGIN_TYPE_NUM]=
   { STRING_WITH_LEN("PASSWORD VALIDATION") },
   { STRING_WITH_LEN("ENCRYPTION") },
   { STRING_WITH_LEN("DATA TYPE") },
+  { STRING_WITH_LEN("FUNCTION") },
   { STRING_WITH_LEN("FUNCTION COLLECTION") }
 };
 
@@ -115,6 +117,7 @@ plugin_type_init plugin_type_initialize[MYSQL_MAX_PLUGIN_TYPE_NUM]=
 {
   0, ha_initialize_handlerton, 0, 0,initialize_schema_table,
   initialize_audit_plugin, 0, 0, 0, initialize_encryption_plugin, 0,
+  0, // FUNCTION
   Plugin_function_collection::init_plugin
 };
 
@@ -122,6 +125,7 @@ plugin_type_init plugin_type_deinitialize[MYSQL_MAX_PLUGIN_TYPE_NUM]=
 {
   0, ha_finalize_handlerton, 0, 0, finalize_schema_table,
   finalize_audit_plugin, 0, 0, 0, finalize_encryption_plugin, 0,
+  0, // FUNCTION
   Plugin_function_collection::deinit_plugin
 };
 
@@ -135,6 +139,7 @@ static int plugin_type_initialization_order[MYSQL_MAX_PLUGIN_TYPE_NUM]=
   MYSQL_DAEMON_PLUGIN,
   MariaDB_ENCRYPTION_PLUGIN,
   MariaDB_DATA_TYPE_PLUGIN,
+  MariaDB_FUNCTION_PLUGIN,
   MariaDB_FUNCTION_COLLECTION_PLUGIN,
   MYSQL_STORAGE_ENGINE_PLUGIN,
   MYSQL_INFORMATION_SCHEMA_PLUGIN,
@@ -179,6 +184,7 @@ static int min_plugin_info_interface_version[MYSQL_MAX_PLUGIN_TYPE_NUM]=
   MariaDB_PASSWORD_VALIDATION_INTERFACE_VERSION,
   MariaDB_ENCRYPTION_INTERFACE_VERSION,
   MariaDB_DATA_TYPE_INTERFACE_VERSION,
+  MariaDB_FUNCTION_INTERFACE_VERSION,
   MariaDB_FUNCTION_COLLECTION_INTERFACE_VERSION
 };
 static int cur_plugin_info_interface_version[MYSQL_MAX_PLUGIN_TYPE_NUM]=
@@ -194,6 +200,7 @@ static int cur_plugin_info_interface_version[MYSQL_MAX_PLUGIN_TYPE_NUM]=
   MariaDB_PASSWORD_VALIDATION_INTERFACE_VERSION,
   MariaDB_ENCRYPTION_INTERFACE_VERSION,
   MariaDB_DATA_TYPE_INTERFACE_VERSION,
+  MariaDB_FUNCTION_INTERFACE_VERSION,
   MariaDB_FUNCTION_COLLECTION_INTERFACE_VERSION
 };