在对DeviceIocontrol 做了一些研究之后，我大部分时间都花在了设计上。这里我分两部分发布代码，为了清楚起见，用命名空间和部分类分开，你可以合并它们但不能单独使用它们。
namespace DiskManagement {
using Microsoft.Win32.SafeHandles;
using LPSECURITY_ATTRIBUTES=IntPtr;
using LPOVERLAPPED=IntPtr;
using LPVOID=IntPtr;
using HANDLE=IntPtr;
using LARGE_INTEGER=Int64;
using DWORD=UInt32;
using LPCTSTR=String;
public static partial class IoCtl /* methods */ {
[DllImport("kernel32.dll", SetLastError=true)]
static extern SafeFileHandle CreateFile(
LPCTSTR lpFileName,
DWORD dwDesiredAccess,
DWORD dwShareMode,
LPSECURITY_ATTRIBUTES lpSecurityAttributes,
DWORD dwCreationDisposition,
DWORD dwFlagsAndAttributes,
HANDLE hTemplateFile
);
[DllImport("kernel32.dll", SetLastError=true)]
static extern DWORD DeviceIoControl(
SafeFileHandle hDevice,
DWORD dwIoControlCode,
LPVOID lpInBuffer,
DWORD nInBufferSize,
LPVOID lpOutBuffer,
int nOutBufferSize,
ref DWORD lpBytesReturned,
LPOVERLAPPED lpOverlapped
);
static DWORD CTL_CODE(DWORD DeviceType, DWORD Function, DWORD Method, DWORD Access) {
return (((DeviceType)<<16)|((Access)<<14)|((Function)<<2)|(Method));
}
public static void Execute<T>(
ref T x,
DWORD dwIoControlCode,
LPCTSTR lpFileName,
DWORD dwDesiredAccess=GENERIC_READ,
DWORD dwShareMode=FILE_SHARE_WRITE|FILE_SHARE_READ,
LPSECURITY_ATTRIBUTES lpSecurityAttributes=default(LPSECURITY_ATTRIBUTES),
DWORD dwCreationDisposition=OPEN_EXISTING,
DWORD dwFlagsAndAttributes=0,
HANDLE hTemplateFile=default(IntPtr)
) {
using(
var hDevice=
CreateFile(
lpFileName,
dwDesiredAccess, dwShareMode,
lpSecurityAttributes,
dwCreationDisposition, dwFlagsAndAttributes,
hTemplateFile
)
) {
if(null==hDevice||hDevice.IsInvalid)
throw new Win32Exception(Marshal.GetLastWin32Error());
var nOutBufferSize=Marshal.SizeOf(typeof(T));
var lpOutBuffer=Marshal.AllocHGlobal(nOutBufferSize);
var lpBytesReturned=default(DWORD);
var NULL=IntPtr.Zero;
var result=
DeviceIoControl(
hDevice, dwIoControlCode,
NULL, 0,
lpOutBuffer, nOutBufferSize,
ref lpBytesReturned, NULL
);
if(0==result)
throw new Win32Exception(Marshal.GetLastWin32Error());
x=(T)Marshal.PtrToStructure(lpOutBuffer, typeof(T));
Marshal.FreeHGlobal(lpOutBuffer);
}
}
}
public enum MEDIA_TYPE: int {
Unknown=0,
F5_1Pt2_512=1,
F3_1Pt44_512=2,
F3_2Pt88_512=3,
F3_20Pt8_512=4,
F3_720_512=5,
F5_360_512=6,
F5_320_512=7,
F5_320_1024=8,
F5_180_512=9,
F5_160_512=10,
RemovableMedia=11,
FixedMedia=12,
F3_120M_512=13,
F3_640_512=14,
F5_640_512=15,
F5_720_512=16,
F3_1Pt2_512=17,
F3_1Pt23_1024=18,
F5_1Pt23_1024=19,
F3_128Mb_512=20,
F3_230Mb_512=21,
F8_256_128=22,
F3_200Mb_512=23,
F3_240M_512=24,
F3_32M_512=25
}
partial class DiskGeometry /* structures */ {
[StructLayout(LayoutKind.Sequential)]
struct DISK_GEOMETRY {
internal LARGE_INTEGER Cylinders;
internal MEDIA_TYPE MediaType;
internal DWORD TracksPerCylinder;
internal DWORD SectorsPerTrack;
internal DWORD BytesPerSector;
}
[StructLayout(LayoutKind.Sequential)]
struct DISK_GEOMETRY_EX {
internal DISK_GEOMETRY Geometry;
internal LARGE_INTEGER DiskSize;
[MarshalAs(UnmanagedType.ByValArray, SizeConst=1)]
internal byte[] Data;
}
}
partial class DiskGeometry /* properties and fields */ {
public MEDIA_TYPE MediaType {
get {
return m_Geometry.MediaType;
}
}
public String MediaTypeName {
get {
return Enum.GetName(typeof(MEDIA_TYPE), this.MediaType);
}
}
public override long Cylinder {
get {
return m_Geometry.Cylinders;
}
}
public override uint Head {
get {
return m_Geometry.TracksPerCylinder;
}
}
public override uint Sector {
get {
return m_Geometry.SectorsPerTrack;
}
}
public DWORD BytesPerSector {
get {
return m_Geometry.BytesPerSector;
}
}
public long DiskSize {
get {
return m_DiskSize;
}
}
public long MaximumLinearAddress {
get {
return m_MaximumLinearAddress;
}
}
public CubicAddress MaximumCubicAddress {
get {
return m_MaximumCubicAddress;
}
}
public DWORD BytesPerCylinder {
get {
return m_BytesPerCylinder;
}
}
CubicAddress m_MaximumCubicAddress;
long m_MaximumLinearAddress;
DWORD m_BytesPerCylinder;
LARGE_INTEGER m_DiskSize;
DISK_GEOMETRY m_Geometry;
}
}
首先，我使用using alias directive 使代码的本机调用更像是在 C/C++ 中。第一部分的重点是IoCtl.Execute 方法。它是一个泛型方法，类型根据传递的第一个参数。它使用P/Invoke 方法隐藏了编组结构和指针的复杂性。第二个参数是将传递给DeviceIoControl 的所需控制代码。第三个到最后一个参数与CreateFile完全相同，都是默认值，可选。
以下是代码的下一部分，可能还有更多要提及的内容。
namespace DiskManagement {
using Microsoft.Win32.SafeHandles;
using LPSECURITY_ATTRIBUTES=IntPtr;
using LPOVERLAPPED=IntPtr;
using LPVOID=IntPtr;
using HANDLE=IntPtr;
using LARGE_INTEGER=Int64;
using DWORD=UInt32;
using LPCTSTR=String;
partial class IoCtl /* constants */ {
public const DWORD
DISK_BASE=0x00000007,
METHOD_BUFFERED=0,
FILE_ANY_ACCESS=0;
public const DWORD
GENERIC_READ=0x80000000,
FILE_SHARE_WRITE=0x2,
FILE_SHARE_READ=0x1,
OPEN_EXISTING=0x3;
public static readonly DWORD DISK_GET_DRIVE_GEOMETRY_EX=
IoCtl.CTL_CODE(DISK_BASE, 0x0028, METHOD_BUFFERED, FILE_ANY_ACCESS);
public static readonly DWORD DISK_GET_DRIVE_GEOMETRY=
IoCtl.CTL_CODE(DISK_BASE, 0, METHOD_BUFFERED, FILE_ANY_ACCESS);
}
public partial class CubicAddress {
public static CubicAddress Transform(long linearAddress, CubicAddress geometry) {
var cubicAddress=new CubicAddress();
var sectorsPerCylinder=geometry.Sector*geometry.Head;
long remainder;
cubicAddress.Cylinder=Math.DivRem(linearAddress, sectorsPerCylinder, out remainder);
cubicAddress.Head=(uint)Math.DivRem(remainder, geometry.Sector, out remainder);
cubicAddress.Sector=1+(uint)remainder;
return cubicAddress;
}
public virtual long Cylinder {
get;
set;
}
public virtual uint Head {
get;
set;
}
public virtual uint Sector {
get;
set;
}
}
public partial class DiskGeometry: CubicAddress {
internal static void ThrowIfDiskSizeOutOfIntegrity(long remainder) {
if(0!=remainder) {
var message="DiskSize is not an integral multiple of a sector size";
throw new ArithmeticException(message);
}
}
public static DiskGeometry FromDevice(String deviceName) {
return new DiskGeometry(deviceName);
}
DiskGeometry(String deviceName) {
var x=new DISK_GEOMETRY_EX();
IoCtl.Execute(ref x, IoCtl.DISK_GET_DRIVE_GEOMETRY_EX, deviceName);
m_DiskSize=x.DiskSize;
m_Geometry=x.Geometry;
long remainder;
m_MaximumLinearAddress=Math.DivRem(DiskSize, BytesPerSector, out remainder)-1;
ThrowIfDiskSizeOutOfIntegrity(remainder);
m_BytesPerCylinder=BytesPerSector*Sector*Head;
m_MaximumCubicAddress=DiskGeometry.Transform(m_MaximumLinearAddress, this);
}
}
}
IoCtl.CTL_CODE原本是C/C++代码中的宏，但是c#没有宏，所以我把DISK_GET_DRIVE_GEOMETRY_EX这样的声明改成static readonly的值，当作运行时常量强>。像IOCTL_ 这样的一些常量的前缀被删除了，因为有类名来限定它们。这部分最大的亮点是类CubicAddress，它是新定义的类DiskGeometry 的基础。您可能想知道为什么甚至更多想知道。
CubicAddress 类其实就是一个简单的类，用于存储物理磁盘的CHS address，并提供了一个将地址从LBA 格式转换的方法，我将其命名为Transform。虽然我从未听说有人将CHS 命名为立方体，但我认为几何/体积之类的术语在数学和围绕物理磁盘方面具有相同的用法。
CHS 可能是(x ,y, z)、(R, G, B) 或任何其他您可以以立方体方式对其进行建模的东西。它们可能有一个用于寻址的坐标，它也可以用来描述几何图形，例如一个向量。因此，CubicAddress 类有两种用法：
CHS/LBA 转换 是线性变换/组合，我只写了Transform，即LBA 到CHS。 Transform 的参数 geometry 是转换所引用的几何，它是必需的，因为线性地址可以转换为具有不同几何的不同坐标。
关于命名，SectorsPerTrack等术语的表示应采用复数形式，如Sectors。但是，由于CubicAddress 的双重用法，我宁愿使用单数形式。
最后，这是测试类
public partial class TestClass {
public static void TestMethod() {
var diskGeometry=DiskGeometry.FromDevice(@"\\.\PhysicalDrive3");
var cubicAddress=diskGeometry.MaximumCubicAddress;
Console.WriteLine(" media type: {0}", diskGeometry.MediaTypeName);
Console.WriteLine();
Console.WriteLine("maximum linear address: {0}", diskGeometry.MaximumLinearAddress);
Console.WriteLine(" last cylinder number: {0}", cubicAddress.Cylinder);
Console.WriteLine(" last head number: {0}", cubicAddress.Head);
Console.WriteLine(" last sector number: {0}", cubicAddress.Sector);
Console.WriteLine();
Console.WriteLine(" cylinders: {0}", diskGeometry.Cylinder);
Console.WriteLine(" tracks per cylinder: {0}", diskGeometry.Head);
Console.WriteLine(" sectors per track: {0}", diskGeometry.Sector);
Console.WriteLine();
Console.WriteLine(" bytes per sector: {0}", diskGeometry.BytesPerSector);
Console.WriteLine(" bytes per cylinder: {0}", diskGeometry.BytesPerCylinder);
Console.WriteLine(" total disk space: {0}", diskGeometry.DiskSize);
}
}