Windows下映射文件夹为虚拟磁盘

/* INCLUDES *****************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <tchar.h>

/* FUNCTIONS ****************************************************************/

void PrintError(DWORD ErrCode)
{
TCHAR *buffer = (TCHAR*) calloc(2048,
sizeof(TCHAR));
TCHAR *msg = NULL;

if (buffer)
{
FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
NULL,
ErrCode,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(TCHAR*)&msg,
0,
NULL);
_sntprintf(buffer,
2048,
_T("操作失败！错误码 0x%x：%s\n"),
ErrCode,
msg);
_tprintf(_T("%s"),
buffer);
if (msg)
LocalFree(msg);
free(buffer);
}
}

void DisplaySubstUsage(void)
{
_tprintf(_T("%s"), _T("将一个路径用驱动器号关联。\n\n\
SUBST [驱动器1: [驱动器2:]路径]\n\
SUBST 驱动器1: /D\n\n\
驱动器1:          指定一个您想要关联到一个路径的虚拟驱动器。\n\
[驱动器2:]路径    指定一个您想要关联到一个虚拟驱动器的物理驱动器和路径。\n\
/D                删除一个虚拟驱动器。\n\n\
执行不带参数的 SUBST 将会显示当前虚拟驱动器的列表。\n"));
}

BOOLEAN IsSubstedDrive(TCHAR *Drive)
{
BOOLEAN Result = FALSE;
LPTSTR lpTargetPath = NULL;
DWORD CharCount, dwSize;

if (_tcslen(Drive) > 2)
return FALSE;

dwSize = sizeof(TCHAR) * MAX_PATH;
lpTargetPath = (LPTSTR) malloc(sizeof(TCHAR) * MAX_PATH);
if ( lpTargetPath)
{
CharCount = QueryDosDevice(Drive,
lpTargetPath,
dwSize / sizeof(TCHAR));
while (! CharCount &&
GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
free(lpTargetPath);
dwSize *= 2;
lpTargetPath = (LPTSTR) malloc(dwSize);
if (lpTargetPath)
{
CharCount = QueryDosDevice(Drive,
lpTargetPath,
dwSize / sizeof(TCHAR));
}
}

if (CharCount)
{
if ( _tcsncmp(lpTargetPath, _T("\\??\\"), 4) == 0 &&
( (lpTargetPath[4] >= _T('A') &&
lpTargetPath[4] <= _T('Z')) ||
(lpTargetPath[4] >= _T('a') &&
lpTargetPath[4] <= _T('z')) ) )
Result = TRUE;
}
free(lpTargetPath);
}
return Result;
}

void DumpSubstedDrives(void)
{
TCHAR Drive[3] = _T("A:");
LPTSTR lpTargetPath = NULL;
DWORD CharCount, dwSize;
INT i = 0;

dwSize = sizeof(TCHAR) * MAX_PATH;
lpTargetPath = (LPTSTR) malloc(sizeof(TCHAR) * MAX_PATH);
if (! lpTargetPath)
return;

while (i < 26)
{
Drive[0] = _T('A') + i;
CharCount = QueryDosDevice(Drive,
lpTargetPath,
dwSize / sizeof(TCHAR));
while (! CharCount &&
GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
free(lpTargetPath);
dwSize *= 2;
lpTargetPath = (LPTSTR) malloc(dwSize);
if (lpTargetPath)
CharCount = QueryDosDevice(Drive,
lpTargetPath,
dwSize / sizeof(TCHAR));
}

if (! CharCount)
{
i++;
continue;
}
else
{
if ( _tcsncmp(lpTargetPath, _T("\\??\\"), 4) == 0 &&
( (lpTargetPath[4] >= _T('A') &&
lpTargetPath[4] <= _T('Z')) ||
(lpTargetPath[4] >= _T('a') &&
lpTargetPath[4] <= _T('z')) ) )
{
_tprintf(_T("%s\\: => %s\n"),
Drive,
lpTargetPath + 4);
}
}
i++;
}
free(lpTargetPath);
}

int DeleteSubst(TCHAR* Drive)
{
BOOL Result;

if (_tcslen(Drive) > 2)
{
_tprintf(_T("无效参数 - %s\n"),
Drive);
return 1;
}

if (! IsSubstedDrive(Drive))
{
_tprintf(_T("无效参数 - %s\n"),
Drive);
return 1;
}

Result = DefineDosDevice(DDD_REMOVE_DEFINITION,
Drive,
NULL);
if (! Result)
{
PrintError(GetLastError());
return 1;
}
return 0;
}

int AddSubst(TCHAR* Drive, TCHAR *Path)
{
BOOL Result;

if (_tcslen(Drive) != 2)
{
_tprintf(_T("无效参数 - %s\n"),
Drive);
return 1;
}

if (Drive[1] != _T(':'))
{
_tprintf(_T("无效参数 - %s\n"),
Drive);
return 1;
}

if (IsSubstedDrive(Drive))
{
_tprintf(_T("驱动器已经运行过 SUBST\n"));
return 1;
}

Result = DefineDosDevice(0,
Drive,
Path);
if (! Result)
{
PrintError(GetLastError());
return 1;
}
return 0;
}

int _tmain(int argc, TCHAR* argv[])
{

for (INT i = 0; i < argc; i++)
{
if (!_tcsicmp(argv[i], _T("/?")))
{
DisplaySubstUsage();
return 0;
}
}

if (argc < 3)
{
if (argc >= 2)
{
_tprintf(_T("参数个数不正确 - %s\n"),
argv[1]);
return 1;
}
DumpSubstedDrives();
return 0;
}

if (argc > 3)
{
_tprintf(_T("参数个数不正确 - %s\n"),
argv[3]);
return 1;
}

if (! _tcsicmp(argv[1], _T("/D")))
return DeleteSubst(argv[2]);
if (! _tcsicmp(argv[2], _T("/D")))
return DeleteSubst(argv[1]);
return AddSubst(argv[1], argv[2]);
}