本代码适用于无操作系统的STM32单片机开发，功能强大。 【付费】STM32嵌入式资料包
可申请到地址空间连续的不同大小的内存空间，且用户接口简单，使用方便。
直接复制粘贴如下代码即可：
memory.h：
#ifndef __MEMORY_H__#define __MEMORY_H__#include "stdio.h"#include "string.h"#include "includes.h"//用户使用typedef struct{void *addr;//申请到的内存的起始地址uint32_t size;//申请到的内存的大小，按照块大小分配，大于等于申请大小uint16_t tb; //申请表序号，申请内存时分配，释放内存时使用，用户不使用}DMEM;//若返回空，则申请失败DMEM *DynMemGet(uint32_t size);void DynMemPut(DMEM *pDmem);#endif //__MEMORY_H__
memory.c：
#include "memory.h"#define DMEM_BLOCK_SIZE 256 //内存块大小为128字节#define DMEM_BLOCK_NUM 20 //内存块个数为40个#define DMEM_TOTAL_SIZE (DMEM_BLOCK_SIZE*DMEM_BLOCK_NUM) //内存总大小typedef enum{DMEM_FREE = 0,DMEM_USED = 1,}DMEM_USED_ITEM;typedef struct{DMEM_USED_ITEM used; //使用状态uint16_t blk_s; //起始块序号uint16_t blk_num; //块个数}DMEM_APPLY;typedef struct{DMEM_USED_ITEM tb_blk[DMEM_BLOCK_NUM];DMEM tb_user[DMEM_BLOCK_NUM]; //用户申请内存信息DMEM_APPLY tb_apply[DMEM_BLOCK_NUM]; //系统分配内存信息uint16_t apply_num; //内存申请表占用数目uint16_t blk_num; //内存块占用数目}DMEM_STATE;static uint8_t DMEMORY[DMEM_TOTAL_SIZE];static DMEM_STATE DMEMS = {0};DMEM *DynMemGet(uint32_t size){uint16_t loop = 0;uint16_t find = 0;uint16_t blk_num_want = 0;DMEM * user = NULL;DMEM_APPLY *apply = NULL;//申请内存大小不能为0if(size == 0) { return NULL; }//申请内存不可超过总内存大小if(size > DMEM_TOTAL_SIZE) { return NULL; }//申请内存不可超过剩余内存大小if(size > (DMEM_BLOCK_NUM - DMEMS.blk_num) * DMEM_BLOCK_SIZE) { return NULL; }//申请表必须有空余if(DMEMS.apply_num >= DMEM_BLOCK_NUM) { return NULL; }//计算所需连续块的个数blk_num_want = (size + DMEM_BLOCK_SIZE - 1) / DMEM_BLOCK_SIZE;//寻找申请表for(loop = 0; loop < DMEM_BLOCK_NUM; loop++){if(DMEMS.tb_apply[loop].used == DMEM_FREE){apply = &DMEMS.tb_apply[loop]; //申请表已找到user = &DMEMS.tb_user[loop]; //用户表对应找到user->tb = loop; //申请表编号记录user->size = blk_num_want * DMEM_BLOCK_SIZE; //分配大小计算break;}}//没有找到可用申请表，理论上是不会出现此现象的，申请表剩余已在上面校验if(loop == DMEM_BLOCK_NUM) { return NULL; }//寻找连续内存块for(loop = 0; loop < DMEM_BLOCK_NUM; loop++){if(DMEMS.tb_blk[loop] == DMEM_FREE){//找到第一个空闲内存块for(find = 1; (find < blk_num_want) && (loop + find < DMEM_BLOCK_NUM); find ++){//找到下一个空闲内存块if(DMEMS.tb_blk[loop + find] != DMEM_FREE){//发现已使用内存块break;}}if(find >= blk_num_want){//寻找到的空闲内存块数目已经够用user->addr = DMEMORY + loop * DMEM_BLOCK_SIZE; //计算申请到的内存的地址apply->blk_s = loop; //记录申请到的内存块首序号apply->blk_num = blk_num_want; //记录申请到的内存块数目for(find = 0 ; find < apply->blk_num; find++){DMEMS.tb_blk[loop + find] = DMEM_USED;}apply->used = DMEM_USED; //标记申请表已使用DMEMS.apply_num += 1;DMEMS.blk_num += blk_num_want;return user;}else{//寻找到的空闲内存块不够用，从下一个开始找loop += find;}}}//搜索整个内存块，未找到大小适合的空间return NULL;}void DynMemPut(DMEM *user){uint16_t loop = 0;//若参数为空，直接返回if(NULL == user) { return; }//释放内存空间for(loop = DMEMS.tb_apply[user->tb].blk_s; loop < DMEMS.tb_apply[user->tb].blk_s + DMEMS.tb_apply[user->tb].blk_num; loop++){DMEMS.tb_blk[loop] = DMEM_FREE;DMEMS.blk_num -= 1;}//释放申请表DMEMS.tb_apply[user->tb].used = DMEM_FREE;DMEMS.apply_num -= 1;}
原文地 址
http://blog.csdn.net/u011833609/article/details/46834203