| /* ==================================================================== |
| * The Apache Software License, Version 1.1 |
| * |
| * Copyright (c) 2001 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, |
| * if any, must include the following acknowledgment: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowledgment may appear in the software itself, |
| * if and wherever such third-party acknowledgments normally appear. |
| * |
| * 4. The names "Apache" and "Apache Software Foundation" must |
| * not be used to endorse or promote products derived from this |
| * software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache", |
| * nor may "Apache" appear in their name, without prior written |
| * permission of the Apache Software Foundation. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| |
| #ifndef APR_OPTIONAL_H |
| #define APR_OPTIONAL_H |
| |
| #include "apu.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* |
| * Typesafe registration and retrieval of functions that may not be present |
| * (i.e. functions exported by optional modules) |
| */ |
| |
| /** |
| * The type of an optional function. |
| * @param name The name of the function |
| */ |
| #define APR_OPTIONAL_FN_TYPE(name) apr_OFN_##name##_t |
| |
| /** |
| * Declare an optional function. |
| * @param ret The return type of the function |
| * @param name The name of the function |
| * @param args The function arguments (including brackets) |
| */ |
| #define APR_DECLARE_OPTIONAL_FN(ret,name,args) \ |
| typedef ret APR_OPTIONAL_FN_TYPE(name) args |
| |
| /* XXX: This doesn't belong here, then! |
| * Private function! DO NOT USE! |
| */ |
| APU_DECLARE_NONSTD(void) apr_register_optional_fn(const char *szName,void (*pfn)(void)); |
| |
| /** |
| * Register an optional function. This can be later retrieved, type-safely, by |
| * name. Like all global functions, the name must be unique. Note that, |
| * confusingly but correctly, the function itself can be static! |
| * @param name The name of the function |
| */ |
| #define APR_REGISTER_OPTIONAL_FN(name) \ |
| ((void (*)(const char *,APR_OPTIONAL_FN_TYPE(name) *))&apr_register_optional_fn)(#name,name) |
| |
| /* Private function! DO NOT USE! */ |
| APU_DECLARE_DATA void (*apr_retrieve_optional_fn(const char *szName))(void); |
| |
| /** |
| * Retrieve an optional function. Returns NULL if the function is not present. |
| * @param name The name of the function |
| */ |
| #define APR_RETRIEVE_OPTIONAL_FN(name) \ |
| (APR_OPTIONAL_FN_TYPE(name) *)apr_retrieve_optional_fn(#name) |
| |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* APR_OPTIONAL_H */ |