/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** * @file apr_optional_hooks.h * @brief Apache optional hook functions */ #ifndef APR_OPTIONAL_HOOK_H #define APR_OPTIONAL_HOOK_H #include "apr_tables.h" #ifdef __cplusplus extern "C" { #endif /** * @defgroup APR_Util_OPT_HOOK Optional Hook Functions * @ingroup APR_Util_Hook * @{ */ /** * Function to implement the APR_OPTIONAL_HOOK Macro * @internal * @see APR_OPTIONAL_HOOK * * @param szName The name of the hook * @param pfn A pointer to a function that will be called * @param aszPre a NULL-terminated array of strings that name modules whose hooks should precede this one * @param aszSucc a NULL-terminated array of strings that name modules whose hooks should succeed this one * @param nOrder an integer determining order before honouring aszPre and aszSucc (for example HOOK_MIDDLE) */ APU_DECLARE(void) apr_optional_hook_add(const char *szName,void (*pfn)(void), const char * const *aszPre, const char * const *aszSucc, int nOrder); /** * Hook to an optional hook. * * @param ns The namespace prefix of the hook functions * @param name The name of the hook * @param pfn A pointer to a function that will be called * @param aszPre a NULL-terminated array of strings that name modules whose hooks should precede this one * @param aszSucc a NULL-terminated array of strings that name modules whose hooks should succeed this one * @param nOrder an integer determining order before honouring aszPre and aszSucc (for example HOOK_MIDDLE) */ #define APR_OPTIONAL_HOOK(ns,name,pfn,aszPre,aszSucc,nOrder) do { \ ns##_HOOK_##name##_t *apu__hook = pfn; \ apr_optional_hook_add(#name,(void (*)(void))apu__hook,aszPre, aszSucc, nOrder); \ } while (0) /** * @internal * @param szName - the name of the function * @return the hook structure for a given hook */ APU_DECLARE(apr_array_header_t *) apr_optional_hook_get(const char *szName); /** * Implement an optional hook that runs until one of the functions * returns something other than OK or DECLINE. * * @param ns The namespace prefix of the hook functions * @param link The linkage declaration prefix of the hook * @param ret The type of the return value of the hook * @param ret The type of the return value of the hook * @param name The name of the hook * @param args_decl The declaration of the arguments for the hook * @param args_use The names for the arguments for the hook * @param ok Success value * @param decline Decline value */ #define APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ns,link,ret,name,args_decl,args_use,ok,decline) \ link##_DECLARE(ret) ns##_run_##name args_decl \ { \ ns##_LINK_##name##_t *pHook; \ int n; \ ret rv; \ apr_array_header_t *pHookArray=apr_optional_hook_get(#name); \ \ if(!pHookArray) \ return ok; \ \ pHook=(ns##_LINK_##name##_t *)pHookArray->elts; \ for(n=0 ; n < pHookArray->nelts ; ++n) \ { \ rv=(pHook[n].pFunc)args_use; \ \ if(rv != ok && rv != decline) \ return rv; \ } \ return ok; \ } /** @} */ #ifdef __cplusplus } #endif #endif /* APR_OPTIONAL_HOOK_H */