apr_optional_hooks.h revision 251876
1251876Speter/* Licensed to the Apache Software Foundation (ASF) under one or more 2251876Speter * contributor license agreements. See the NOTICE file distributed with 3251876Speter * this work for additional information regarding copyright ownership. 4251876Speter * The ASF licenses this file to You under the Apache License, Version 2.0 5251876Speter * (the "License"); you may not use this file except in compliance with 6251876Speter * the License. You may obtain a copy of the License at 7251876Speter * 8251876Speter * http://www.apache.org/licenses/LICENSE-2.0 9251876Speter * 10251876Speter * Unless required by applicable law or agreed to in writing, software 11251876Speter * distributed under the License is distributed on an "AS IS" BASIS, 12251876Speter * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13251876Speter * See the License for the specific language governing permissions and 14251876Speter * limitations under the License. 15251876Speter */ 16251876Speter/** 17251876Speter * @file apr_optional_hooks.h 18251876Speter * @brief Apache optional hook functions 19251876Speter */ 20251876Speter 21251876Speter 22251876Speter#ifndef APR_OPTIONAL_HOOK_H 23251876Speter#define APR_OPTIONAL_HOOK_H 24251876Speter 25251876Speter#include "apr_tables.h" 26251876Speter 27251876Speter#ifdef __cplusplus 28251876Speterextern "C" { 29251876Speter#endif 30251876Speter/** 31251876Speter * @defgroup APR_Util_OPT_HOOK Optional Hook Functions 32251876Speter * @ingroup APR_Util_Hook 33251876Speter * @{ 34251876Speter */ 35251876Speter/** 36251876Speter * Function to implemnt the APR_OPTIONAL_HOOK Macro 37251876Speter * @internal 38251876Speter * @see APR_OPTIONAL_HOOK 39251876Speter * 40251876Speter * @param name The name of the hook 41251876Speter * @param pfn A pointer to a function that will be called 42251876Speter * @param aszPre a NULL-terminated array of strings that name modules whose hooks should precede this one 43251876Speter * @param aszSucc a NULL-terminated array of strings that name modules whose hooks should succeed this one 44251876Speter * @param nOrder an integer determining order before honouring aszPre and aszSucc (for example HOOK_MIDDLE) 45251876Speter */ 46251876Speter 47251876Speter 48251876SpeterAPU_DECLARE(void) apr_optional_hook_add(const char *szName,void (*pfn)(void), 49251876Speter const char * const *aszPre, 50251876Speter const char * const *aszSucc, 51251876Speter int nOrder); 52251876Speter 53251876Speter/** 54251876Speter * Hook to an optional hook. 55251876Speter * 56251876Speter * @param ns The namespace prefix of the hook functions 57251876Speter * @param name The name of the hook 58251876Speter * @param pfn A pointer to a function that will be called 59251876Speter * @param aszPre a NULL-terminated array of strings that name modules whose hooks should precede this one 60251876Speter * @param aszSucc a NULL-terminated array of strings that name modules whose hooks should succeed this one 61251876Speter * @param nOrder an integer determining order before honouring aszPre and aszSucc (for example HOOK_MIDDLE) 62251876Speter */ 63251876Speter 64251876Speter#define APR_OPTIONAL_HOOK(ns,name,pfn,aszPre,aszSucc,nOrder) do { \ 65251876Speter ns##_HOOK_##name##_t *apu__hook = pfn; \ 66251876Speter apr_optional_hook_add(#name,(void (*)(void))apu__hook,aszPre, aszSucc, nOrder); \ 67251876Speter} while (0) 68251876Speter 69251876Speter/** 70251876Speter * @internal 71251876Speter * @param szName - the name of the function 72251876Speter * @return the hook structure for a given hook 73251876Speter */ 74251876SpeterAPU_DECLARE(apr_array_header_t *) apr_optional_hook_get(const char *szName); 75251876Speter 76251876Speter/** 77251876Speter * Implement an optional hook that runs until one of the functions 78251876Speter * returns something other than OK or DECLINE. 79251876Speter * 80251876Speter * @param ns The namespace prefix of the hook functions 81251876Speter * @param link The linkage declaration prefix of the hook 82251876Speter * @param ret The type of the return value of the hook 83251876Speter * @param ret The type of the return value of the hook 84251876Speter * @param name The name of the hook 85251876Speter * @param args_decl The declaration of the arguments for the hook 86251876Speter * @param args_use The names for the arguments for the hook 87251876Speter * @param ok Success value 88251876Speter * @param decline Decline value 89251876Speter */ 90251876Speter#define APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ns,link,ret,name,args_decl,args_use,ok,decline) \ 91251876Speterlink##_DECLARE(ret) ns##_run_##name args_decl \ 92251876Speter { \ 93251876Speter ns##_LINK_##name##_t *pHook; \ 94251876Speter int n; \ 95251876Speter ret rv; \ 96251876Speter apr_array_header_t *pHookArray=apr_optional_hook_get(#name); \ 97251876Speter\ 98251876Speter if(!pHookArray) \ 99251876Speter return ok; \ 100251876Speter\ 101251876Speter pHook=(ns##_LINK_##name##_t *)pHookArray->elts; \ 102251876Speter for(n=0 ; n < pHookArray->nelts ; ++n) \ 103251876Speter { \ 104251876Speter rv=(pHook[n].pFunc)args_use; \ 105251876Speter\ 106251876Speter if(rv != ok && rv != decline) \ 107251876Speter return rv; \ 108251876Speter } \ 109251876Speter return ok; \ 110251876Speter } 111251876Speter 112251876Speter/** @} */ 113251876Speter#ifdef __cplusplus 114251876Speter} 115251876Speter#endif 116251876Speter 117251876Speter#endif /* APR_OPTIONAL_HOOK_H */ 118