apr_generic_hook.h

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

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#ifndef APR_GENERIC_HOOK_H
#define APR_GENERIC_HOOK_H

#include "apr_tables.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @package Apache hooks functions
 */

#define APR_DECLARE_GENERIC_HOOK(ns,ret,name,args) \
typedef ret ns##_HOOK_##name args;

APU_DECLARE(void) apr_hook_generic_add(const char *szName,void (*pfn)(void),
				   const char * const *aszPre,
				   const char * const *aszSucc,int nOrder);

/**
 * Hook to a generic hook.
 *
 * @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_HOOK_GENERIC(name,pfn,aszPre,aszSucc,nOrder) \
    ((void (*)(const char *,HOOK_##name *,const char * const *, \
	       const char * const *,int))&apr_hook_generic_add)(#name,pfn,aszPre, \
							   aszSucc, nOrder)

APU_DECLARE(apr_array_header_t *) apr_hook_generic_get(const char *szName);

/**
 * Implement a generic hook that runs until one of the functions
 * returns something other than OK or DECLINE.
 *
 * @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_used The names for the arguments for the hook
 * @deffunc int APR_IMPLEMENT_EXTERNAL_HOOK_RUN_ALL(link, name, args_decl, args_use)
 */
#define APR_IMPLEMENT_GENERIC_HOOK_RUN_ALL(ns,link,ret,name,args_decl,args_use,ok,decline) \
link##_DECLARE(ret) ns##_run_##name args_decl \
    { \
    ns##_LINK_##name *pHook; \
    int n; \
    ret rv; \
    apr_array_header_t *pHookArray=apr_hook_generic_get(#name); \
\
    if(!pHookArray) \
	return ok; \
\
    pHook=(ns##_LINK_##name *)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_GENERIC_HOOK_H */