00001 /* 00002 * Copyright (c) 2004-2005, Swedish Institute of Computer Science. 00003 * All rights reserved. 00004 * 00005 * Redistribution and use in source and binary forms, with or without 00006 * modification, are permitted provided that the following conditions 00007 * are met: 00008 * 1. Redistributions of source code must retain the above copyright 00009 * notice, this list of conditions and the following disclaimer. 00010 * 2. Redistributions in binary form must reproduce the above copyright 00011 * notice, this list of conditions and the following disclaimer in the 00012 * documentation and/or other materials provided with the distribution. 00013 * 3. Neither the name of the Institute nor the names of its contributors 00014 * may be used to endorse or promote products derived from this software 00015 * without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 00018 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00019 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00020 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 00021 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00022 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00023 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00024 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00025 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00026 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00027 * SUCH DAMAGE. 00028 * 00029 * This file is part of the Contiki operating system. 00030 * 00031 * Author: Adam Dunkels <adam@sics.se> 00032 * 00033 * $Id: lc-addrlabels.h,v 1.4 2006/06/03 11:29:43 adam Exp $ 00034 */ 00035 00036 /** 00037 * \addtogroup lc 00038 * @{ 00039 */ 00040 00041 /** 00042 * \file 00043 * Implementation of local continuations based on the "Labels as 00044 * values" feature of gcc 00045 * \author 00046 * Adam Dunkels <adam@sics.se> 00047 * 00048 * This implementation of local continuations is based on a special 00049 * feature of the GCC C compiler called "labels as values". This 00050 * feature allows assigning pointers with the address of the code 00051 * corresponding to a particular C label. 00052 * 00053 * For more information, see the GCC documentation: 00054 * http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html 00055 * 00056 */ 00057 00058 #ifndef __LC_ADDRLABELS_H__ 00059 #define __LC_ADDRLABELS_H__ 00060 00061 /** \hideinitializer */ 00062 typedef void * lc_t; 00063 00064 #define LC_INIT(s) s = NULL 00065 00066 #define LC_RESUME(s) \ 00067 do { \ 00068 if(s != NULL) { \ 00069 goto *s; \ 00070 } \ 00071 } while(0) 00072 00073 #define LC_CONCAT2(s1, s2) s1##s2 00074 #define LC_CONCAT(s1, s2) LC_CONCAT2(s1, s2) 00075 00076 #define LC_SET(s) \ 00077 do { \ 00078 LC_CONCAT(LC_LABEL, __LINE__): \ 00079 (s) = &&LC_CONCAT(LC_LABEL, __LINE__); \ 00080 } while(0) 00081 00082 #define LC_END(s) 00083 00084 #endif /* __LC_ADDRLABELS_H__ */ 00085 /** @} */