// Copyright (C) 2013, 2015 Internet Systems Consortium, Inc. ("ISC") // // This Source Code Form is subject to the terms of the Mozilla Public // License, v. 2.0. If a copy of the MPL was not distributed with this // file, You can obtain one at http://mozilla.org/MPL/2.0/. #ifndef HOOKS_H #define HOOKS_H #include #include namespace { // Version 3 of the hooks framework, set for Kea 1.0. const int KEA_HOOKS_VERSION = 3; // Names of the framework functions. const char* const LOAD_FUNCTION_NAME = "load"; const char* const UNLOAD_FUNCTION_NAME = "unload"; const char* const VERSION_FUNCTION_NAME = "version"; // Typedefs for pointers to the framework functions. typedef int (*version_function_ptr)(); typedef int (*load_function_ptr)(isc::hooks::LibraryHandle&); typedef int (*unload_function_ptr)(); } // Anonymous namespace namespace isc { namespace hooks { /// @brief User-Library Initialization for Statically-Linked Kea /// /// If Kea is statically-linked, a user-created hooks library will not be /// able to access symbols in it. In particular, it will not be able to access /// singleton objects. /// /// The hooks framework handles some of this. For example, although there is /// a singleton ServerHooks object, hooks framework objects store a reference /// to it when they are created. When the user library needs to register a /// callout (which requires access to the ServerHooks information), it accesses /// the ServerHooks object through a pointer passed from the Kea image. /// /// The logging framework is more problematical. Here the code is partly /// statically linked (the Kea logging library) and partly shared (the /// log4cplus). The state of the former is not accessible to the user library, /// but the state of the latter is. So within the user library, we need to /// initialize the Kea logging library but not initialize the log4cplus /// code. Some of the initialization is done when the library is loaded, but /// other parts are done at run-time. /// /// This function - to be called by the user library code in its load() function /// when running against a statically linked Kea - initializes the Kea /// logging library. In particular, it loads the message dictionary with the /// text of the Kea messages. /// /// @note This means that the virtual address space is loaded with two copies /// of the message dictionary. Depending on how the user libraries are linked, /// loading multiple user libraries may involve loading one message dictionary /// per library. void hooksStaticLinkInit(); } // namespace hooks } // namespace isc #endif // HOOKS_H