dofat.c

都在一个程序里

  
/*以读取硬盘C盘 FAT32的FAT为例，来调用读取硬盘绝对扇区的函数 */
#include "dolba.h"

/*获取FAT参数（FAT前距离DBR的扇区数，FAT所占的扇区数）*/
void getFATinfo(unsigned int hardDisk,
	unsigned int *reservedSector,
	unsigned long *sectorPerFAT)
{
unsigned char buffer[512];
unsigned int fat16=0;
unsigned long fat32=0;
//unsigned int f16;
//unsigned int f32;
/*获取DBR，以便 获取FAT参数 */
biosdisk(2,hardDisk,1,0,1,1,buffer);
/* 获取FAT前距离DBR的扇区数 */
*reservedSector=*((unsigned int *)&buffer[0xE]);

fat16=*((unsigned int *)&buffer[0x16]);
fat32=*((unsigned long *)&buffer[0x24]);
//f16=*((unsigned int *)&buffer[0x39]);
//f32=*((unsigned int *)&buffer[0x55]);
/* 获取FAT所占的扇区数 */
if(fat16!=0) *sectorPerFAT=fat16;
else if(fat32!=0) *sectorPerFAT=fat32;
else {printf("FAT information not found.\n"); return;}
}

void doFat(char *prompt,unsigned int cmd, char *buf,char *showFileName)
{
unsigned int reservedSector=0;
unsigned long sectorPerFAT=0;

/* 获取FAT参数  */
getFATinfo(0x80,&reservedSector,&sectorPerFAT);
if(reservedSector==0 || sectorPerFAT==0)
{printf("DBR or FAT information error.\n"); return;}
/*保存FAT到文件  */
//printf("%u,%lu",reservedSector,sectorPerFAT);
//printf("%d,%d\n",reservedSector,sectorPerFAT);
//return;
doLBA(prompt,cmd,0x80,63+reservedSector,sectorPerFAT,buf,showFileName);
}