public override bool FileExists(System.String fullPath)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, true);
return((errorCode == 0) && (data.fileAttributes != -1) &&
((data.fileAttributes & Interop.FILE_ATTRIBUTE_DIRECTORY) == 0));
}
private bool DirectoryExists(String path, out int lastError)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
lastError = FillAttributeInfo(path, ref data, false, true);
return((lastError == 0) && (data.fileAttributes != -1) &&
((data.fileAttributes & Interop.FILE_ATTRIBUTE_DIRECTORY) != 0));
}
public override FileAttributes GetAttributes(string fullPath)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, true);
if (errorCode != 0)
{
throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath);
}
return((FileAttributes)data.fileAttributes);
}
private void EnsureDataInitialized()
{
if (_dataInitialised == -1)
{
_data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
Refresh();
}
if (_dataInitialised != 0) // Refresh was unable to initialise the data
{
throw Win32Marshal.GetExceptionForWin32Error(_dataInitialised, _fullPath);
}
}
public override DateTimeOffset GetLastWriteTime(string fullPath)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, false);
if (errorCode != 0)
{
throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath);
}
long dt = ((long)data.ftLastWriteTimeHigh << 32) | ((long)data.ftLastWriteTimeLow);
return(DateTimeOffset.FromFileTime(dt));
}
[System.Security.SecurityCritical] // auto-generated
internal static int FillAttributeInfo(String path, ref Interop.WIN32_FILE_ATTRIBUTE_DATA data, bool tryagain, bool returnErrorOnNotFound)
{
int errorCode = 0;
if (tryagain) // someone has a handle to the file open, or other error
{
Interop.WIN32_FIND_DATA findData;
findData = new Interop.WIN32_FIND_DATA();
// Remove trialing slash since this can cause grief to FindFirstFile. You will get an invalid argument error
String tempPath = path.TrimEnd(PathHelpers.DirectorySeparatorChars);
// For floppy drives, normally the OS will pop up a dialog saying
// there is no disk in drive A:, please insert one. We don't want that.
// SetErrorMode will let us disable this, but we should set the error
// mode back, since this may have wide-ranging effects.
uint oldMode = Interop.mincore.SetErrorMode(Interop.SEM_FAILCRITICALERRORS);
try
{
bool error = false;
SafeFindHandle handle = Interop.mincore.FindFirstFile(tempPath, ref findData);
try
{
if (handle.IsInvalid)
{
error = true;
errorCode = Marshal.GetLastWin32Error();
if (errorCode == Interop.ERROR_FILE_NOT_FOUND ||
errorCode == Interop.ERROR_PATH_NOT_FOUND ||
errorCode == Interop.ERROR_NOT_READY) // floppy device not ready
{
if (!returnErrorOnNotFound)
{
// Return default value for backward compatibility
errorCode = 0;
data.fileAttributes = -1;
}
}
return(errorCode);
}
}
finally
{
// Close the Win32 handle
try
{
handle.Dispose();
}
catch
{
// if we're already returning an error, don't throw another one.
if (!error)
{
throw Win32Marshal.GetExceptionForLastWin32Error();
}
}
}
}
finally
{
Interop.mincore.SetErrorMode(oldMode);
}
// Copy the information to data
data.PopulateFrom(findData);
}
else
{
// For floppy drives, normally the OS will pop up a dialog saying
// there is no disk in drive A:, please insert one. We don't want that.
// SetErrorMode will let us disable this, but we should set the error
// mode back, since this may have wide-ranging effects.
bool success = false;
uint oldMode = Interop.mincore.SetErrorMode(Interop.SEM_FAILCRITICALERRORS);
try
{
success = Interop.mincore.GetFileAttributesEx(path, Interop.GET_FILEEX_INFO_LEVELS.GetFileExInfoStandard, ref data);
}
finally
{
Interop.mincore.SetErrorMode(oldMode);
}
if (!success)
{
errorCode = Marshal.GetLastWin32Error();
if (errorCode != Interop.ERROR_FILE_NOT_FOUND &&
errorCode != Interop.ERROR_PATH_NOT_FOUND &&
errorCode != Interop.ERROR_NOT_READY) // floppy device not ready
{
// In case someone latched onto the file. Take the perf hit only for failure
return(FillAttributeInfo(path, ref data, true, returnErrorOnNotFound));
}
else
{
if (!returnErrorOnNotFound)
{
// Return default value for backward compatibility
errorCode = 0;
data.fileAttributes = -1;
}
}
}
}
return(errorCode);
}
private void EnsureDataInitialized()
{
if (_dataInitialised == -1)
{
_data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
Refresh();
}
if (_dataInitialised != 0) // Refresh was unable to initialise the data
throw Win32Marshal.GetExceptionForWin32Error(_dataInitialised, _fullPath);
}
private bool ShouldUseWinRT(string fullPath, bool isCreate)
{
// The purpose of this method is to determine if we can access a path
// via Win32 or if we need to fallback to WinRT.
// We prefer Win32 since it is faster, WinRT's APIs eventually just
// call into Win32 after all, but it doesn't provide access to,
// brokered paths (like Pictures or Documents) nor does it handle
// placeholder files. So we'd like to fall back to WinRT whenever
// we can't access a path, or if it known to be a placeholder file.
bool useWinRt = false;
do
{
// first use GetFileAttributesEx as it is faster than FindFirstFile and requires minimum permissions
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
if (Interop.mincore.GetFileAttributesEx(fullPath, Interop.GET_FILEEX_INFO_LEVELS.GetFileExInfoStandard, ref data))
{
// got the attributes
if ((data.fileAttributes & Interop.FILE_ATTRIBUTE_DIRECTORY) != 0 ||
(data.fileAttributes & Interop.FILE_ATTRIBUTE_REPARSE_POINT) == 0)
{
// we have a directory or a file that is not a reparse point
// useWinRt = false;
break;
}
else
{
// we need to get the find data to determine if it is a placeholder file
Interop.WIN32_FIND_DATA findData = new Interop.WIN32_FIND_DATA();
using (SafeFindHandle handle = Interop.mincore.FindFirstFile(fullPath, ref findData))
{
if (!handle.IsInvalid)
{
// got the find data, use WinRT for placeholder files
Debug.Assert((findData.dwFileAttributes & Interop.FILE_ATTRIBUTE_DIRECTORY) == 0);
Debug.Assert((findData.dwFileAttributes & Interop.FILE_ATTRIBUTE_REPARSE_POINT) != 0);
useWinRt = findData.dwReserved0 == Interop.IO_REPARSE_TAG_FILE_PLACEHOLDER;
break;
}
}
}
}
int error = Marshal.GetLastWin32Error();
Debug.Assert(error != Interop.ERROR_SUCCESS);
if (error == Interop.ERROR_ACCESS_DENIED)
{
// The path was not accessible with Win32, so try WinRT
useWinRt = true;
break;
}
else if (error != Interop.ERROR_PATH_NOT_FOUND && error != Interop.ERROR_FILE_NOT_FOUND)
{
// We hit some error other than ACCESS_DENIED or NOT_FOUND,
// Default to Win32 to provide most accurate error behavior
break;
}
// error was ERROR_PATH_NOT_FOUND or ERROR_FILE_NOT_FOUND
// if we are creating a file/directory we cannot assume that Win32 will have access to
// the parent directory, so we walk up the path.
fullPath = PathHelpers.GetDirectoryNameInternal(fullPath);
// only walk up the path if we are creating a file/directory and not at the root
} while (isCreate && !String.IsNullOrEmpty(fullPath));
return(useWinRt);
}
public override void RemoveDirectory(string fullPath, bool recursive)
{
// Do not recursively delete through reparse points. Perhaps in a
// future version we will add a new flag to control this behavior,
// but for now we're much safer if we err on the conservative side.
// This applies to symbolic links and mount points.
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, true);
if (errorCode != 0)
{
// Ensure we throw a DirectoryNotFoundException.
if (errorCode == Interop.ERROR_FILE_NOT_FOUND)
errorCode = Interop.ERROR_PATH_NOT_FOUND;
throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath);
}
if (((FileAttributes)data.fileAttributes & FileAttributes.ReparsePoint) != 0)
recursive = false;
RemoveDirectoryHelper(fullPath, recursive, true);
}
public override DateTimeOffset GetLastWriteTime(string fullPath)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, false);
if (errorCode != 0)
throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath);
long dt = ((long)data.ftLastWriteTimeHigh << 32) | ((long)data.ftLastWriteTimeLow);
return DateTimeOffset.FromFileTime(dt);
}
public override FileAttributes GetAttributes(string fullPath)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, true);
if (errorCode != 0)
throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath);
return (FileAttributes)data.fileAttributes;
}
public override bool FileExists(System.String fullPath)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
int errorCode = FillAttributeInfo(fullPath, ref data, false, true);
return (errorCode == 0) && (data.fileAttributes != -1)
&& ((data.fileAttributes & Interop.FILE_ATTRIBUTE_DIRECTORY) == 0);
}
private bool DirectoryExists(String path, out int lastError)
{
Interop.WIN32_FILE_ATTRIBUTE_DATA data = new Interop.WIN32_FILE_ATTRIBUTE_DATA();
lastError = FillAttributeInfo(path, ref data, false, true);
return (lastError == 0) && (data.fileAttributes != -1)
&& ((data.fileAttributes & Interop.FILE_ATTRIBUTE_DIRECTORY) != 0);
}
