给出文件绝对路径,能否得到文件再磁盘的起始位置(簇,扇区)信息
类似于如下伪代码
GetFileInDeviceInfo(char* 文件路径)
{
//得到磁盘所在起始簇号
//簇连
//簇结束位置
。。。。
}
问题如标题
用户层或者驱动层是否有相关参考代码,在此感谢各位了!
在下只找到类似于这样的源码,还能有更详细的源码不
使用函数
DeviceIoControl(hFile, FSCTL_GET_RETRIEVAL_POINTERS, &InBuf,
sizeof(InBuf), OutBuf, OutSize, &Bytes, NULL))
就可以查询文件的簇链
下面是个例如直接读取扇区来拷贝文件的例子
用法:FileCopy("C://boot.ini", "D://boot.ini");
C/C++ code
ULONGLONG *GetFileClusters(
LPCSTR lpFileName,
ULONG ClusterSize,
ULONG *ClCount,
ULONG *FileSize
)
{
HANDLE hFile;
ULONG OutSize;
ULONG Bytes, Cls, CnCount, r;
ULONGLONG *Clusters = NULL;
BOOLEAN Result = FALSE;
LARGE_INTEGER PrevVCN, Lcn;
STARTING_VCN_INPUT_BUFFER InBuf;
PRETRIEVAL_POINTERS_BUFFER OutBuf;
hFile = CreateFile(lpFileName, FILE_READ_ATTRIBUTES,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
NULL, OPEN_EXISTING, 0, 0);
if (hFile != INVALID_HANDLE_VALUE)
{
*FileSize = GetFileSize(hFile, NULL);
OutSize = sizeof(RETRIEVAL_POINTERS_BUFFER) + (*FileSize / ClusterSize) * sizeof(OutBuf->Extents);
OutBuf = (PRETRIEVAL_POINTERS_BUFFER)malloc(OutSize);
InBuf.StartingVcn.QuadPart = 0;
if (DeviceIoControl(hFile, FSCTL_GET_RETRIEVAL_POINTERS, &InBuf,
sizeof(InBuf), OutBuf, OutSize, &Bytes, NULL))
{
*ClCount = (*FileSize + ClusterSize - 1) / ClusterSize;
Clusters = (PULONGLONG)malloc(*ClCount * sizeof(ULONGLONG));
PrevVCN = OutBuf->StartingVcn;
for (r = 0, Cls = 0; r < OutBuf->ExtentCount; r++)
{
Lcn = OutBuf->Extents[r].Lcn;
for (CnCount = (ULONG)(OutBuf->Extents[r].NextVcn.QuadPart - PrevVCN.QuadPart);
CnCount; CnCount--, Cls++, Lcn.QuadPart++) Clusters[Cls] = Lcn.QuadPart;
PrevVCN = OutBuf->Extents[r].NextVcn;
}
}
free(OutBuf);
CloseHandle(hFile);
}
return Clusters;
}
BOOL FileCopy(LPCSTR lpSrcName, LPCSTR lpDstName)
{
BOOL bResult = FALSE;
ULONG ClusterSize, BlockSize;
ULONGLONG *Clusters;
ULONG ClCount, FileSize, Bytes;
HANDLE hDrive, hFile;
ULONG SecPerCl, BtPerSec, r;
PVOID Buff;
LARGE_INTEGER Offset;
CHAR Name[7];
Name[0] = lpSrcName[0];
Name[1] = ':';
Name[2] = 0;
GetDiskFreeSpace(Name, &SecPerCl, &BtPerSec, NULL, NULL);
ClusterSize = SecPerCl * BtPerSec;
Clusters = GetFileClusters(lpSrcName, ClusterSize, &ClCount, &FileSize);
if(Clusters)
{
Name[0] = '//';
Name[1] = '//';
Name[2] = '.';
Name[3] = '//';
Name[4] = lpSrcName[0];
Name[5] = ':';
Name[6] = 0;
hDrive = CreateFile(Name, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
if (hDrive != INVALID_HANDLE_VALUE)
{
hFile = CreateFile(lpDstName, GENERIC_WRITE, 0, NULL, CREATE_NEW, 0, 0);
if (hFile != INVALID_HANDLE_VALUE)
{
Buff = malloc(ClusterSize);
for (r = 0; r < ClCount; r++, FileSize -= BlockSize)
{
Offset.QuadPart = ClusterSize * Clusters[r];
SetFilePointer(hDrive, Offset.LowPart, &Offset.HighPart, FILE_BEGIN);
ReadFile(hDrive, Buff, ClusterSize, &Bytes, NULL);
BlockSize = FileSize < ClusterSize ? FileSize : ClusterSize;
WriteFile(hFile, Buff, BlockSize, &Bytes, NULL);
}
free(Buff);
CloseHandle(hFile);
bResult = TRUE;
}
CloseHandle(hDrive);
}
free(Clusters);
}
else
{
printf("GetFileClusters fail./n");
}
return bResult;
}
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