|
// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
/*============================================================
**
** Class: DriveInfo
**
** <OWNER>Microsoft</OWNER>
**
**
** Purpose: Exposes routines for exploring a drive.
**
**
===========================================================*/
using System;
using System.Text;
using System.Runtime.InteropServices;
using Microsoft.Win32;
using System.Security.Permissions;
using System.Runtime.Serialization;
using System.Runtime.Versioning;
using System.Diagnostics.Contracts;
namespace System.IO
{
// Matches Win32's DRIVE_XXX #defines from winbase.h
[Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public enum DriveType
{
Unknown = 0,
NoRootDirectory = 1,
Removable = 2,
Fixed = 3,
Network = 4,
CDRom = 5,
Ram = 6
}
// Ideally we'll get a better security permission, but possibly
// not for Whidbey.
[Serializable]
[ComVisible(true)]
public sealed class DriveInfo : ISerializable
{
private String _name;
private const String NameField = "_name"; // For serialization
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.Machine)]
[ResourceConsumption(ResourceScope.Machine)]
public DriveInfo(String driveName)
{
if (driveName == null)
throw new ArgumentNullException("driveName");
Contract.EndContractBlock();
if (driveName.Length == 1)
_name = driveName + ":\\";
else {
// GetPathRoot does not check all invalid characters
Path.CheckInvalidPathChars(driveName);
_name = Path.GetPathRoot(driveName);
// Disallow null or empty drive letters and UNC paths
if (_name == null || _name.Length == 0 || _name.StartsWith("\\\\", StringComparison.Ordinal))
throw new ArgumentException(Environment.GetResourceString("Arg_MustBeDriveLetterOrRootDir"));
}
// We want to normalize to have a trailing backslash so we don't have two equivalent forms and
// because some Win32 API don't work without it.
if (_name.Length == 2 && _name[1] == ':') {
_name = _name + "\\";
}
// Now verify that the drive letter could be a real drive name.
// On Windows this means it's between A and Z, ignoring case.
// On a Unix platform, perhaps this should be a device name with
// a partition like /dev/hdc0, or possibly a mount point.
char letter = driveName[0];
if (!((letter >= 'A' && letter <= 'Z') || (letter >= 'a' && letter <= 'z')))
throw new ArgumentException(Environment.GetResourceString("Arg_MustBeDriveLetterOrRootDir"));
// Now do a security check.
String demandPath = _name + '.';
new FileIOPermission(FileIOPermissionAccess.PathDiscovery, demandPath).Demand();
}
[System.Security.SecurityCritical] // auto-generated
private DriveInfo(SerializationInfo info, StreamingContext context)
{
// Need to add in a security check here once it has been spec'ed.
_name = (String) info.GetValue(NameField, typeof(String));
// Now do a security check.
String demandPath = _name + '.';
new FileIOPermission(FileIOPermissionAccess.PathDiscovery, demandPath).Demand();
}
public String Name {
get { return _name; }
}
public DriveType DriveType {
[System.Security.SecuritySafeCritical] // auto-generated
get {
// GetDriveType can't fail
return (DriveType) Win32Native.GetDriveType(Name);
}
}
public String DriveFormat {
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Process, ResourceScope.Process)]
get {
const int volNameLen = 50;
StringBuilder volumeName = new StringBuilder(volNameLen);
const int fileSystemNameLen = 50;
StringBuilder fileSystemName = new StringBuilder(fileSystemNameLen);
int serialNumber, maxFileNameLen, fileSystemFlags;
int oldMode = Win32Native.SetErrorMode(Win32Native.SEM_FAILCRITICALERRORS);
try {
bool r = Win32Native.GetVolumeInformation(Name, volumeName, volNameLen, out serialNumber, out maxFileNameLen, out fileSystemFlags, fileSystemName, fileSystemNameLen);
if (!r) {
int errorCode = Marshal.GetLastWin32Error();
__Error.WinIODriveError(Name, errorCode);
}
}
finally {
Win32Native.SetErrorMode(oldMode);
}
return fileSystemName.ToString();
}
}
public bool IsReady {
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Machine, ResourceScope.Machine)]
get {
return Directory.InternalExists(Name);
}
}
public long AvailableFreeSpace {
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Process, ResourceScope.Process)]
get {
long userBytes, totalBytes, freeBytes;
int oldMode = Win32Native.SetErrorMode(Win32Native.SEM_FAILCRITICALERRORS);
try {
bool r = Win32Native.GetDiskFreeSpaceEx(Name, out userBytes, out totalBytes, out freeBytes);
if (!r)
__Error.WinIODriveError(Name);
}
finally {
Win32Native.SetErrorMode(oldMode);
}
return userBytes;
}
}
public long TotalFreeSpace {
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Process, ResourceScope.Process)]
get {
long userBytes, totalBytes, freeBytes;
int oldMode = Win32Native.SetErrorMode(Win32Native.SEM_FAILCRITICALERRORS);
try {
bool r = Win32Native.GetDiskFreeSpaceEx(Name, out userBytes, out totalBytes, out freeBytes);
if (!r)
__Error.WinIODriveError(Name);
}
finally {
Win32Native.SetErrorMode(oldMode);
}
return freeBytes;
}
}
public long TotalSize {
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Process, ResourceScope.Process)]
get {
// Don't cache this, to handle variable sized floppy drives
// or other various removable media drives.
long userBytes, totalBytes, freeBytes;
int oldMode = Win32Native.SetErrorMode(Win32Native.SEM_FAILCRITICALERRORS);
try {
bool r = Win32Native.GetDiskFreeSpaceEx(Name, out userBytes, out totalBytes, out freeBytes);
if (!r)
__Error.WinIODriveError(Name);
}
finally {
Win32Native.SetErrorMode(oldMode);
}
return totalBytes;
}
}
[ResourceExposure(ResourceScope.Machine)]
[ResourceConsumption(ResourceScope.Machine)]
public static DriveInfo[] GetDrives()
{
// Directory.GetLogicalDrives demands unmanaged code permission
String[] drives = Directory.GetLogicalDrives();
DriveInfo[] di = new DriveInfo[drives.Length];
for(int i=0; i<drives.Length; i++)
di[i] = new DriveInfo(drives[i]);
return di;
}
public DirectoryInfo RootDirectory {
[ResourceExposure(ResourceScope.Machine)]
[ResourceConsumption(ResourceScope.Machine)]
get {
return new DirectoryInfo(Name);
}
}
// Null is a valid volume label.
public String VolumeLabel {
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Process, ResourceScope.Process)]
get {
// NTFS uses a limit of 32 characters for the volume label,
// as of Windows Server 2003.
const int volNameLen = 50;
StringBuilder volumeName = new StringBuilder(volNameLen);
const int fileSystemNameLen = 50;
StringBuilder fileSystemName = new StringBuilder(fileSystemNameLen);
int serialNumber, maxFileNameLen, fileSystemFlags;
int oldMode = Win32Native.SetErrorMode(Win32Native.SEM_FAILCRITICALERRORS);
try {
bool r = Win32Native.GetVolumeInformation(Name, volumeName, volNameLen, out serialNumber, out maxFileNameLen, out fileSystemFlags, fileSystemName, fileSystemNameLen);
if (!r) {
int errorCode = Marshal.GetLastWin32Error();
// Win9x appears to return ERROR_INVALID_DATA when a
// drive doesn't exist.
if (errorCode == Win32Native.ERROR_INVALID_DATA)
errorCode = Win32Native.ERROR_INVALID_DRIVE;
__Error.WinIODriveError(Name, errorCode);
}
}
finally {
Win32Native.SetErrorMode(oldMode);
}
return volumeName.ToString();
}
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[ResourceConsumption(ResourceScope.Process, ResourceScope.Process)]
set {
String demandPath = _name + '.';
new FileIOPermission(FileIOPermissionAccess.Write, demandPath).Demand();
int oldMode = Win32Native.SetErrorMode(Win32Native.SEM_FAILCRITICALERRORS);
try {
bool r = Win32Native.SetVolumeLabel(Name, value);
if (!r) {
int errorCode = Marshal.GetLastWin32Error();
// Provide better message
if (errorCode == Win32Native.ERROR_ACCESS_DENIED)
throw new UnauthorizedAccessException(Environment.GetResourceString("InvalidOperation_SetVolumeLabelFailed"));
__Error.WinIODriveError(Name, errorCode);
}
}
finally {
Win32Native.SetErrorMode(oldMode);
}
}
}
public override String ToString()
{
return Name;
}
#if FEATURE_SERIALIZATION
/// <internalonly/>
[System.Security.SecurityCritical]
void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
{
// No need for an additional security check - everything is public.
info.AddValue(NameField, _name, typeof(String));
}
#endif
}
}
|