Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved. How to create a new service ^^^^^^^^^^^^^^^^^^^^^^^^^^^ A "service" is a set of C functions in a structure that a service dynamic linker uses when a dynamic plugin is loaded. If you want to export C++ class you need to provide an extern "C" function that will create a new instance of your class, and put it in a service. Data structures are not part of the service structure, but they are part of the API you create and usually need to be declared in the same service_*.h file. To turn a set of functions (foo_func1, foo_func2) into a service "foo" you need to 1. create a new file include/mysql/service_foo.h 2. the template is ================================================================== #ifndef MYSQL_SERVICE_FOO_INCLUDED /* standard GPL header */ /** @file *exhaustive* description of the interface you provide. This file is the main user documentation of the new service */ #ifdef __cplusplus extern "C" { #endif extern struct foo_service_st { int (*foo_func1_type)(...); /* fix the prototype as appropriate */ void (*foo_func2_type)(...); /* fix the prototype as appropriate */ } *foo_service; #ifdef MYSQL_DYNAMIC_PLUGIN #define foo_func1(...) foo_service->foo_func1_type(...) #define foo_func2(...) foo_service->foo_func2_type(...) #else int foo_func1_type(...); /* fix the prototype as appropriate */ void foo_func2_type(...); /* fix the prototype as appropriate */ #endif #ifdef __cplusplus } #endif #define MYSQL_SERVICE_FOO_INCLUDED #endif ================================================================== the service_foo.h file should be self-contained, if it needs system headers - include them in it, e.g. if you use size_t - #include it should also declare all the accompanying data structures, as necessary (e.g. thd_alloc_service declares MYSQL_LEX_STRING). 3. add the new file to include/Makefile.am (pkginclude_HEADERS) 4. add the new file to include/mysql/services.h 5. increase the minor plugin ABI version in include/mysql/plugin.h (MYSQL_PLUGIN_INTERFACE_VERSION = MYSQL_PLUGIN_INTERFACE_VERSION+1) 6. add the version of your service to include/service_versions.h: ================================================================== #define VERSION_foo 0x0100 ================================================================== 7. create a new file libservices/foo_service.c using the following template: ================================================================== /* GPL header */ #include SERVICE_VERSION *foo_service= (void*)VERSION_foo; ================================================================== 8. add the new file to libservices/CMakeLists.txt (MYSQLSERVICES_SOURCES) 9. add the new file to libservices/Makefile.am (libmysqlservices_a_SOURCES) 10. and finally, register your service for dynamic linking in sql/sql_plugin_services.h 10.1 fill in the service structure: ================================================================== static struct foo_service_st foo_handler = { foo_func1, foo_func2 } ================================================================== 10.2 and add it to the list of services ================================================================== { "foo_service", VERSION_foo, &foo_handler } ================================================================== that's all.