磁盘格式化程序——测试程序

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我是靠谱客的博主威武大神，最近开发中收集的这篇文章主要介绍磁盘格式化程序——测试程序，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

/*testfs.c*/

#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include "rt.h"

static char *program_name="testfs";
static int DEV=-1;
static char *device_name=NULL;
static char super_block_buffer[1024];
static char i_point_buffer[4096];
static char zone_map[10240];
static long got;

static void die(char *str){
fprintf(stderr,"%s:",program_name);
fprintf(stderr,str,device_name);
fprintf(stderr,"n");
exit(8);
}

main()
{
device_name="/dev/sdb1";
DEV=open(device_name,O_RDWR);
if(DEV<0)
die("unable to open %s");

//读超级块
if(lseek(DEV,1024,SEEK_SET)!=1024)
die("seek to super block failed!");
got=read(DEV,super_block_buffer,1024);
printf("s_magic = %dn",(*(struct rt_super_block *)super_block_buffer).s_magic);
printf("s_total_blocks_count = %dn",(*(struct rt_super_block *)super_block_buffer).s_total_blocks_count);
printf("s_ipoint_start_position = %dn",(*(struct rt_super_block *)super_block_buffer).s_ipoint_start_position);
printf("s_ipoints_count = %dn",(*(struct rt_super_block *)super_block_buffer).s_ipoints_count);
printf("s_ipoint_size = %dn",(*(struct rt_super_block *)super_block_buffer).s_ipoint_size);

printf("s_cluster_map_start_position = %dn",(*(struct rt_super_block *)super_block_buffer).s_cluster_map_start_position);
printf("s_cluster_map_count = %dn",(*(struct rt_super_block *)super_block_buffer).s_cluster_map_count);
printf("s_cluster_start_position = %dn",(*(struct rt_super_block *)super_block_buffer).s_cluster_start_position);
printf("s_cluster_size = %dn",(*(struct rt_super_block *)super_block_buffer).s_cluster_size);
printf("s_cluster_count = %dn",(*(struct rt_super_block *)super_block_buffer).s_cluster_count);

//读点索引区
if(lseek(DEV,2048,SEEK_SET)!=2048)
die("seek to ipoint zone failed!");
got=read(DEV,i_point_buffer,4096);
int i;
for(i=0;i<1024;i++)
{
printf("Point[%d] = %dn",i,(*(struct rt_ipoint *)i_point_buffer).i_latest_cluster[i]);
}

//读数据簇位图
if(lseek(DEV,6144,SEEK_SET)!=6144)
die("seek to cluster zone map failed!");
got=read(DEV,zone_map,10240);
for(i=0;i<130;i++)
{
printf("Byte[%d] = %cn",i,zone_map[i]);
}

}

/*rt.h*/

#include <linux/fs.h>
#include <linux/types.h>
#include <linux/magic.h>

#define RT_SUPER_MAGIC 0x0920
#define RT_BLOCK_SIZE 1024

#define CLUSTER_SIZE 50
#define DATAZONEBASE 16

#define RT_IPOINT_SIZE 4
#define RT_IPOINT_BLOCKS 4
#define RT_IPOINT_START_POSITION 2

#define RT_CLUSTERMAP_BLOCKS 10
#define RT_CLUSTERMAP_START_POSITION 6

#define RT_BLOCKS_PER_CLUSTER 50
#define RT_CLUSTER_START_POSITION 16

#define RT_IPOINTS_PER_BLOCK ((RT_BLOCK_SIZE)/RT_IPOINT_SIZE)
#define RT_IPOINTS_COUNT (RT_IPOINTS_PER_BLOCK*RT_IPOINT_BLOCKS)

struct rt_ipoint{
__le32 i_latest_cluster[RT_IPOINTS_COUNT];
};

struct rt_super_block{
__le64 s_total_blocks_count;        //the total blocks of the partation
__le16 s_ipoint_start_position; //the point index start position default 2
__le16 s_ipoints_count;        //points count default 1024
__le16 s_ipoint_num;             //point num default 0
__u8   s_ipoint_size;            //point size default 4 Byte
__le32 s_cluster_map_start_position; //cluster bit map start position default 6(block) block=1024 byte;
__le16 s_cluster_map_count;          //default 10 blocks
__le16 s_cluster_start_position;   //cluster start position default 16 (block)
__u8   s_cluster_size;            //cluster size =50 blocks
__le64 s_cluster_num;           //current cluster number
__le64 s_cluster_count;          //clusters count
__le64 s_create_time;      //rtfs create time
__le64 s_write_time;       //the recent write time
__le64 s_read_time;       //the read time
__le16 s_magic;            //the magic of rtfs default 2336
};