/* * Copyright (c) 2004, Swedish Institute of Computer Science. * 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. Neither the name of the Institute nor the names of its contributors *    may be used to endorse or promote products derived from this software *    without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS 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 INSTITUTE OR 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 file is part of the uIP TCP/IP stack * * Author: Adam Dunkels <adam@sics.se> * * $Id: memb.h,v 1.1 2006/06/12 08:21:43 adam Exp $ *//** * \defgroup memb Memory block management functions * * The memory block allocation routines provide a simple yet powerful * set of functions for managing a set of memory blocks of fixed * size. A set of memory blocks is statically declared with the * MEMB() macro. Memory blocks are allocated from the declared * memory by the memb_alloc() function, and are deallocated with the * memb_free() function. * * \note Because of namespace clashes only one MEMB() can be * declared per C module, and the name scope of a MEMB() memory * block is local to each C module. * * The following example shows how to declare and use a memory block * called "cmem" which has 8 chunks of memory with each memory chunk * being 20 bytes large. * * @{ *//** * \file *         Memory block allocation routines. * \author *         Adam Dunkels <adam@sics.se> * */#ifndef __MEMB_H__#define __MEMB_H__/* * Here we define a C preprocessing macro for concatenating to * strings. We need use two macros in order to allow concatenation of * two #defined macros. */#define MEMB_CONCAT2(s1, s2) s1##s2#define MEMB_CONCAT(s1, s2) MEMB_CONCAT2(s1, s2)/** * Declare a memory block. * * This macro is used to staticall declare a block of memory that can * be used by the block allocation functions. The macro statically * declares a C array with a size that matches the specified number of * blocks and their individual sizes. * * Example: \codeMEMB(connections, sizeof(struct connection), 16); \endcode * * \param name The name of the memory block (later used with * memb_init(), memb_alloc() and memb_free()). * * \param size The size of each memory chunk, in bytes. * * \param num The total number of memory chunks in the block. * */#define MEMB(name, structure, num) \        static char MEMB_CONCAT(name,_memb_count)[num]; \        static structure MEMB_CONCAT(name,_memb_mem)[num]; \        static struct memb_blocks name = {sizeof(structure), num, \                                          MEMB_CONCAT(name,_memb_count), \                                          (void *)MEMB_CONCAT(name,_memb_mem)}struct memb_blocks {  unsigned short size;  unsigned short num;  char *count;  void *mem;};/** * Initialize a memory block that was declared with MEMB(). * * \param m A memory block previosly declared with MEMB(). */void  memb_init(struct memb_blocks *m);/** * Allocate a memory block from a block of memory declared with MEMB(). * * \param m A memory block previosly declared with MEMB(). */void *memb_alloc(struct memb_blocks *m);/** * Deallocate a memory block from a memory block previously declared * with MEMB(). * * \param m m A memory block previosly declared with MEMB(). * * \param ptr A pointer to the memory block that is to be deallocated. * * \return The new reference count for the memory block (should be 0 * if successfully deallocated) or -1 if the pointer "ptr" did not * point to a legal memory block. */char  memb_free(struct memb_blocks *m, void *ptr);/** @} */#endif /* __MEMB_H__ */