/*
函数功能： 顺序读取整个文件
参数 ： Target_File 目标文件
返回值 ： u8*
*/
u8* ReadFile(FS_Object* Target_File)
{
if(Target_File->CurClus==FS_EOF)
{
return (void*)0;
}
if(Target_File->CurSec==FS.Sec_PerClus)
{
Target_File->CurSec=0;
Target_File->CurClus=Read_NextClusNum(Target_File->CurClus);
if(Target_File->CurClus==FS_EOF)
{
return (void*)0;
}
}
ReadSec(Target_File->CurClus,Target_File->CurSec,FS_Buffer);
Target_File->CurSec++;
return (u8*)FS_Buffer;
}
/*********************************************************************************************************
** 函数名称: FATGetNextClus
** 功能描述: 返回FAT表指定簇的下一个簇号
**
** 输 入: Index：簇号
** 输 出: 下一个簇号
**
** 全局变量: 无
** 调用模块: 无
**
********************************************************************************************************/
Uint32 FATGetNextClus(Uint32 Index)
{
Uint16 temp, ByteIndex;
Uint32 SecIndex;
Uint8 *Buf;
Uint32 Rt;
if (Index >= (DiskInfo.ClusPerData))
{
return BAD_CLUS;
}
/* 计算扇区号和字节索引 */
switch (DiskInfo.FATType)
{
case FAT12:
SecIndex = Index * 3 / (2 * DiskInfo.BytsPerSec);
ByteIndex = ((Index * 3) / 2) - (SecIndex * DiskInfo.BytsPerSec);
SecIndex += DiskInfo.FATStartSec;
break;
case FAT16:
SecIndex = Index * 2 / DiskInfo.BytsPerSec + DiskInfo.FATStartSec;
ByteIndex = (Index * 2) & (DiskInfo.BytsPerSec - 1);
break;
case FAT32:
SecIndex = Index * 4 / DiskInfo.BytsPerSec + DiskInfo.FATStartSec;
ByteIndex = (Index * 4) & (DiskInfo.BytsPerSec - 1);
break;
default:
return BAD_CLUS;
}
Buf = OpenSec(SecIndex);
if (Buf == NULL)
{
return BAD_CLUS;
}
ReadSec(SecIndex, 0);
/* 读取FAT表数据 */
switch (DiskInfo.FATType)
{
case FAT12:
temp = Buf[ByteIndex];
ByteIndex++;
if (ByteIndex >= DiskInfo.BytsPerSec) /* 下一个字节是否在下一个扇区 */
{
Buf = OpenSec(SecIndex + 1);
if (Buf == NULL)
{
return BAD_CLUS;
}
ReadSec(SecIndex + 1, 0);
temp = temp | (Buf[0] << 8);
}
else
{
temp = temp | (Buf[ByteIndex] << 8);
}
if ((Index & 0x01) != 0) /* 判断哪12位有效 */
{
temp = temp >> 4;
}
else
{
/*
函数功能： 在文件夹中创建新文件(夹)，并获取新创建文件(夹)参数
参数 ： CurDir 当前文件夹
Target 目标文件(夹)，新文件(夹)创建完成后，参数存于此结构体
Target_Name 目标文件(夹)名，新文件(夹)以此命名
Object FILE或DIR，用于区分将要创建的是文件还是文件夹
返回值 ： NAME_ERROR 文件(夹)名错误，此文件(夹)已存在。
FILE_FAILED 文件(夹)创建失败，空间不足
FILE_SUCCESSED 文件(夹)创建成功
*/
FS_Status CreateNewObject(FS_Object* CurDir,FS_Object *Target,u8 *Target_Name,u8 Object)
{
DIR_tag *DirTag;
u32 LastClus;
u32 CurClus;
u32 NewObject_FstClus;
u8 CurSec;
u16 CurEntAddr;
u32 TotalClus;
if(Search_inDir(CurDir,Target,Target_Name,Object)==FILE_NOTEXIST)
{
TotalClus=(FS.FS_Size-FS.Data_Addr)/FS.Bytes_PerClus;
CurClus=CurDir->FstClus;
do
{
/***** Read and Scan FS_Object Data Aera by Sector ******/
for(CurSec=0;CurSec<FS.Sec_PerClus;CurSec++)
{
ReadSec(CurClus,CurSec,FS_Buffer);
/***** Scan Every DirEntry , 32 Bytes per DirEntry! *****/
for(CurEntAddr=0;CurEntAddr<BYTES_PERSEC;CurEntAddr+=DIRENT_SIZE)
{
DirTag=(DIR_tag*)((u32)FS_Buffer+CurEntAddr);
if((DirTag->FileName[0]==EMPTY)||(DirTag->FileName[0]==DELETED))
{
NewObject_FstClus=Write_NextClusNum(FST_CLUS);
ReadSec(CurClus,CurSec,FS_Buffer);
Write_ShortNm(Target_Name,DirTag->FileName);
DirTag->Attribute=Object;
DirTag->FstClusHI=(u16)(NewObject_FstClus>>16);
DirTag->FstClusLO=(u16)NewObject_FstClus;
DirTag->FileLength=0x00;
WriteSec(CurClus,CurSec,FS_Buffer);
Target->Name=Target_Name;
Target->Attrib=Object;
Target->Size=0;
Target->FstClus=NewObject_FstClus;
Target->DirEntryAddr=Get_ClusAddr(CurClus)+CurSec*BYTES_PERSEC+CurEntAddr;
Target->CurClus=Target->FstClus;
Target->CurSec=0;
return FILE_SUCCESSED;
}
}
}
LastClus=CurClus;
CurClus=Read_NextClusNum(CurClus);
if(CurClus==FS_EOF)
{
CurClus=Write_NextClusNum(LastClus);
USART1_printf("NextClusNum:0x%x",CurClus);
if(CurClus==FS_EOF)
{
return FILE_FAILED;
}
}
}
/*
函数功能： 列出文件夹中的所有项目
参数 ： CurDir 当前文件夹
返回值 ： void
*/
void LsDir(FS_Object* CurDir)
{
DIR_tag *DirTag;
LongDir_Ent *LongDirEnt;
u32 CurClus;
u16 CurEntAddr;
u8 CurSec,LngNmCnt,DirEntCnt;
u16 Name_Buffer[53]; //最多容纳4个目录项 共52个Unicode字符
u8 *Name;
Name_Buffer[52]=0;
CurClus=CurDir->FstClus;
LngNmCnt=4;
DirEntCnt=4;
do
{
/***** Read and Scan FS_Object Data Aera by Sector ******/
for(CurSec=0;CurSec<FS.Sec_PerClus;CurSec++)
{
ReadSec(CurClus,CurSec,FS_Buffer);
/***** Scan Every DirEntry , 32 Bytes per DirEntry! *****/
for(CurEntAddr=0;CurEntAddr<BYTES_PERSEC;CurEntAddr+=DIRENT_SIZE)
{
DirTag=(DIR_tag*)((u32)FS_Buffer+CurEntAddr);
if(DirTag->FileName[0]==EMPTY)
{
return;
}
if(DirTag->FileName[0]!=DELETED)
{
if(DirTag->Attribute==LONG_NAME)
{
if(LngNmCnt!=0)
{
LngNmCnt--;
LongDirEnt=(LongDir_Ent*)DirTag;
Name=(u8 *)Name_Buffer+LngNmCnt*26;
CopyRam(LongDirEnt->Name1,Name,10);
CopyRam(LongDirEnt->Name2,Name+10,12);
CopyRam(LongDirEnt->Name3,Name+22,4);
}
}
else if(DirTag->Attribute&(DIR|FILE))
{
if(DirTag->Attribute&DIR)
{
USART_SendStr(USART1,"Dir:");
}
else
{
USART_SendStr(USART1,"File:");
}
if(LngNmCnt!=4)
{
LngNmCnt=4;
Convert_LngNm(Name);
USART_SendStr(USART1,Name);
USART1_printf("\r\n");
}
else
{
Name=(u8 *)Name_Buffer;
CopyRam(DirTag->FileName,Name,11);
Convert_ShortNm(Name);
USART_SendStr(USART1,Name);
USART1_printf("\r\n");
}
}
}
if(LngNmCnt!=4)
{
DirEntCnt--;
}
if(LngNmCnt!=DirEntCnt)
{
LngNmCnt=4;
DirEntCnt=4;
}
}
}
CurClus=Read_NextClusNum(CurClus);
}
while(CurClus!=0x0fffffff);
return;
}
/*
函数功能： 根据文件(夹)名在文件夹中寻找文件(夹)，如果找到则获取文件(夹)参数
参数 ： CurDir 结构体指针，当前文件夹
Target 结构体指针，目标文件(夹)
Target_Name 目标文件(夹)名
Object FILE或DIR，用于区分目标是文件还是文件夹
返回值 ： FILE_EXIST或FILE_NOTEXIST
*/
FS_Status Search_inDir(FS_Object *CurDir,
FS_Object *Target,
u8 *Target_Name,
u8 Object)
{
DIR_tag *DirTag;
LongDir_Ent *LongDirEnt;
u32 CurClus;
u16 CurEntAddr;
u8 CurSec,LngNmCnt,DirEntCnt;
u16 Name_Buffer[53]; //最多容纳4个目录项 共52个Unicode字符
u8 *Name;
Name_Buffer[52]=0;
CurClus=CurDir->FstClus;
LngNmCnt=4;
DirEntCnt=4;
do
{
/***** Read and Scan FS_Object Data Aera by Sector ******/
for(CurSec=0;CurSec<FS.Sec_PerClus;CurSec++)
{
ReadSec(CurClus,CurSec,FS_Buffer);
/***** Scan Every DirEntry , 32 Bytes per DirEntry! *****/
for(CurEntAddr=0;CurEntAddr<BYTES_PERSEC;CurEntAddr+=DIRENT_SIZE)
{
DirTag=(DIR_tag*)((u32)FS_Buffer+CurEntAddr);
if(DirTag->FileName[0]==EMPTY)
{
return FILE_NOTEXIST;
}
if(DirTag->FileName[0]!=DELETED)
{
if(DirTag->Attribute==LONG_NAME)
{
if(LngNmCnt!=0)
{
LngNmCnt--;
LongDirEnt=(LongDir_Ent*)DirTag;
Name=(u8 *)Name_Buffer+LngNmCnt*26;
CopyRam(LongDirEnt->Name1,Name,10);
CopyRam(LongDirEnt->Name2,Name+10,12);
CopyRam(LongDirEnt->Name3,Name+22,4);
}
}
else if(DirTag->Attribute&Object)
{
if(LngNmCnt!=4)
{
LngNmCnt=4;
Convert_LngNm(Name);
}
else
{
Name=(u8 *)Name_Buffer;
CopyRam(DirTag->FileName,Name,11);
Convert_ShortNm(Name);
}
if(CompareName(Name,Target_Name)==SUCCESSED)
{
Target->Name =Target_Name;
Target->Attrib =DirTag->Attribute;
Target->Size =DirTag->FileLength;
Target->FstClus=DirTag->FstClusHI;
Target->FstClus<<=16;
Target->FstClus+=DirTag->FstClusLO;
Target->DirEntryAddr=Get_ClusAddr(CurClus)
+CurSec*BYTES_PERSEC
+CurEntAddr;
Target->CurClus=Target->FstClus;
Target->CurSec=0;
return FILE_EXIST;
}
}
if(LngNmCnt!=4)
{
DirEntCnt--;
}
if(LngNmCnt!=DirEntCnt)
{
LngNmCnt=4;
DirEntCnt=4;
}
}
}
}
CurClus=Read_NextClusNum(CurClus);
}
while(CurClus!=0x0fffffff);
return FILE_NOTEXIST;
}
