C# 9 Tool Help Functionsを利用してプロセス、スレッド、モジュール、ヒープリストのスナップショットを作成するクラス

前書き

Windows XPから導入されたTool Help Functionsを利用してプロセス、スレッド、モジュール、ヒープリストのスナップショットを作成するクラスのコードです。

ソースコード

// Potisan.Windows.ToolHelp32.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Runtime.InteropServices;

namespace Potisan.Windows.ToolHelp32
{
    public sealed class ToolHelp32SnapshotHandle : SafeHandle
    {
        [Flags]
        public enum Flags : uint
        {
            Inheritable = 0x80000000,
            SnapHeapList = 0x00000001,
            SnapProcess = 0x00000002,
            SnapThread = 0x00000004,
            SnapModule = 0x00000008,
            SnapModule32 = 0x00000010,
            SnapAll = SnapHeapList | SnapModule | SnapProcess | SnapThread,
        }

        private ToolHelp32SnapshotHandle()
            : base(IntPtr.Zero, true)
        {
        }

        public static ToolHelp32SnapshotHandle Snap(Flags flags, uint processId)
        {
            var handle = NativeMethods.CreateToolhelp32Snapshot((uint)flags, processId);
            if (handle.IsInvalid)
                throw new Win32Exception();
            return handle;
        }

        public static ToolHelp32SnapshotHandle SnapAll(bool includesModule32, bool inheritable = false)
            => Snap(Flags.SnapAll | (includesModule32 ? Flags.SnapModule32 : 0), 0);

        public static ToolHelp32SnapshotHandle SnapProcess(bool inheritable = false)
            => Snap(Flags.SnapProcess | (inheritable ? Flags.Inheritable : 0), 0);

        public static ToolHelp32SnapshotHandle SnapThreads(uint processId, bool inheritable = false)
            => Snap(Flags.SnapThread | (inheritable ? Flags.Inheritable : 0), processId);

        public static ToolHelp32SnapshotHandle SnapHeapLists(uint processId, bool inheritable = false)
            => Snap(Flags.SnapHeapList | (inheritable ? Flags.Inheritable : 0), processId);

        public static ToolHelp32SnapshotHandle SnapModules(uint processId, bool includesModule32, bool inheritable = false)
            => Snap(Flags.SnapModule
                | (inheritable ? Flags.Inheritable : 0)
                | (includesModule32 ? Flags.SnapModule32 : 0),
                processId);

        public override bool IsInvalid => handle == default;

        protected override bool ReleaseHandle() => NativeMethods.CloseHandle(handle);

        private static class NativeMethods
        {
            [DllImport("Kernel32.dll", SetLastError = true)]
            public extern static ToolHelp32SnapshotHandle CreateToolhelp32Snapshot(
                uint flags, uint processId);

            [DllImport("kernel32.dll", SetLastError = true)]
            [return: MarshalAs(UnmanagedType.Bool)]
            public extern static bool CloseHandle(IntPtr handle);
        }
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
    public struct ToolHelp32ProcessInfo
    {
        public uint Size;
        public uint UsageCount;
        public uint ProcessID;
        public UIntPtr DefaultHeapID;
        public uint ModuleID;
        public uint ThreadCount;
        public uint ParentProcessID;
        public int PriorityClassBase;
        public uint Flags;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
        public string ExeFileName;
    }

    public sealed class ToolHelp32ProcessInfos : IEnumerable<ToolHelp32ProcessInfo>
    {
        private ToolHelp32SnapshotHandle handle;

        public ToolHelp32ProcessInfos(ToolHelp32SnapshotHandle handle)
            => this.handle = handle;

        public ToolHelp32SnapshotHandle SnapshotHandle => handle;

        public IEnumerator<ToolHelp32ProcessInfo> GetEnumerator()
            => new ToolHelp32ProcessInfoEnumerator(handle);

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
            => new ToolHelp32ProcessInfoEnumerator(handle);
    }

    public sealed class ToolHelp32ProcessInfoEnumerator : IEnumerator<ToolHelp32ProcessInfo>
    {
        private ToolHelp32SnapshotHandle handle;
        private ToolHelp32ProcessInfo info;

        private ToolHelp32ProcessInfoEnumerator(ToolHelp32SnapshotHandle handle)
        {
            this.handle = handle;
            Reset();
        }

        public ToolHelp32SnapshotHandle SnapshotHandle => handle;

        public ToolHelp32ProcessInfo Current => info;

        public void Dispose() { }

        object System.Collections.IEnumerator.Current => info;

        public bool MoveNext()
        {
            if (!NativeMethods.Process32Next(handle, ref info))
            {
                if (Marshal.GetLastWin32Error() != ERROR_NO_MORE_FILES)
                {
                    Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
                }
                return false;
            }
            return true;
        }

        public void Reset()
        {
            info.Size = (uint)Marshal.SizeOf<ToolHelp32ProcessInfo>();
            if (!NativeMethods.Process32First(handle, ref info))
            {
                Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
            }
        }

        private const int ERROR_NO_MORE_FILES = 18;

        private static class NativeMethods
        {
            [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
            [return: MarshalAs(UnmanagedType.Bool)]
            public extern static bool Process32First(
                ToolHelp32SnapshotHandle handle,
                ref ToolHelp32ProcessInfo info);

            [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
            [return: MarshalAs(UnmanagedType.Bool)]
            public extern static bool Process32Next(
                ToolHelp32SnapshotHandle handle,
                ref ToolHelp32ProcessInfo info);
        }
    }
}

ToolHelp32ProcessInfo.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Runtime.InteropServices;

namespace Potisan.Windows.ToolHelp32
{
    public sealed class ToolHelp32SnapshotHandle : SafeHandle
    {
        [Flags]
        public enum Flags : uint
        {
            Inheritable = 0x80000000,
            SnapHeapList = 0x00000001,
            SnapProcess = 0x00000002,
            SnapThread = 0x00000004,
            SnapModule = 0x00000008,
            SnapModule32 = 0x00000010,
            SnapAll = SnapHeapList | SnapModule | SnapProcess | SnapThread,
        }

        private ToolHelp32SnapshotHandle()
            : base(IntPtr.Zero, true)
        {
        }

        public static ToolHelp32SnapshotHandle Snap(Flags flags, uint processId)
        {
            var handle = NativeMethods.CreateToolhelp32Snapshot((uint)flags, processId);
            if (handle.IsInvalid)
                throw new Win32Exception();
            return handle;
        }

        public static ToolHelp32SnapshotHandle SnapAll(bool includesModule32, bool inheritable = false)
            => Snap(Flags.SnapAll | (includesModule32 ? Flags.SnapModule32 : 0), 0);

        public static ToolHelp32SnapshotHandle SnapProcess(bool inheritable = false)
            => Snap(Flags.SnapProcess | (inheritable ? Flags.Inheritable : 0), 0);

        public static ToolHelp32SnapshotHandle SnapThreads(uint processId, bool inheritable = false)
            => Snap(Flags.SnapThread | (inheritable ? Flags.Inheritable : 0), processId);

        public static ToolHelp32SnapshotHandle SnapHeapLists(uint processId, bool inheritable = false)
            => Snap(Flags.SnapHeapList | (inheritable ? Flags.Inheritable : 0), processId);

        public static ToolHelp32SnapshotHandle SnapModules(uint processId, bool includesModule32, bool inheritable = false)
            => Snap(Flags.SnapModule
                | (inheritable ? Flags.Inheritable : 0)
                | (includesModule32 ? Flags.SnapModule32 : 0),
                processId);

        public override bool IsInvalid => handle == default;

        protected override bool ReleaseHandle() => NativeMethods.CloseHandle(handle);

        private static class NativeMethods
        {
            [DllImport("Kernel32.dll", SetLastError = true)]
            public extern static ToolHelp32SnapshotHandle CreateToolhelp32Snapshot(
                uint flags, uint processId);

            [DllImport("kernel32.dll", SetLastError = true)]
            [return: MarshalAs(UnmanagedType.Bool)]
            public extern static bool CloseHandle(IntPtr handle);
        }
    }

    [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]
    public struct ToolHelp32ProcessInfo
    {
        public uint Size;
        public uint UsageCount;
        public uint ProcessID;
        public UIntPtr DefaultHeapID;
        public uint ModuleID;
        public uint ThreadCount;
        public uint ParentProcessID;
        public int PriorityClassBase;
        public uint Flags;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
        public string ExeFileName;
    }

    public sealed class ToolHelp32ProcessInfos : IEnumerable<ToolHelp32ProcessInfo>
    {
        private ToolHelp32SnapshotHandle handle;

        public ToolHelp32ProcessInfos(ToolHelp32SnapshotHandle handle)
            => this.handle = handle;

        public ToolHelp32SnapshotHandle SnapshotHandle => handle;

        public IEnumerator<ToolHelp32ProcessInfo> GetEnumerator()
            => new ToolHelp32ProcessInfoEnumerator(handle);

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
            => new ToolHelp32ProcessInfoEnumerator(handle);
    }

    public sealed class ToolHelp32ProcessInfoEnumerator : IEnumerator<ToolHelp32ProcessInfo>
    {
        private ToolHelp32SnapshotHandle handle;
        private ToolHelp32ProcessInfo info;

        internal ToolHelp32ProcessInfoEnumerator(ToolHelp32SnapshotHandle handle)
        {
            this.handle = handle;
            Reset();
        }

        public ToolHelp32SnapshotHandle SnapshotHandle => handle;

        public ToolHelp32ProcessInfo Current => info;

        public void Dispose() { }

        object System.Collections.IEnumerator.Current => info;

        public bool MoveNext()
        {
            if (!NativeMethods.Process32Next(handle, ref info))
            {
                if (Marshal.GetLastWin32Error() != ERROR_NO_MORE_FILES)
                {
                    Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
                }
                return false;
            }
            return true;
        }

        public void Reset()
        {
            info.Size = (uint)Marshal.SizeOf<ToolHelp32ProcessInfo>();
            if (!NativeMethods.Process32First(handle, ref info))
            {
                Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
            }
        }

        private const int ERROR_NO_MORE_FILES = 18;

        private static class NativeMethods
        {
            [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
            [return: MarshalAs(UnmanagedType.Bool)]
            public extern static bool Process32First(
                ToolHelp32SnapshotHandle handle,
                ref ToolHelp32ProcessInfo info);

            [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
            [return: MarshalAs(UnmanagedType.Bool)]
            public extern static bool Process32Next(
                ToolHelp32SnapshotHandle handle,
                ref ToolHelp32ProcessInfo info);
        }
    }
}

サンプルコード

プロセスIDの列挙

// Program.cs
using System;
using Potisan.Text.Format;
using Potisan.Windows.ToolHelp32;

var formatter = new FieldArrayFormatter();
using (var snapshot = ToolHelp32SnapshotHandle.SnapProcess())
{
    foreach (var processInfo in new ToolHelp32ProcessInfos(snapshot))
    {
        Console.WriteLine(formatter.Format(null, processInfo, null));
    }
}

// Potisan.Text.FieldArrayFormatter.cs
using System;
using System.Text;

namespace Potisan.Text.Format
{
    public sealed class FieldArrayFormatter : IFormatProvider, ICustomFormatter
    {
        public object GetFormat(Type formatType)
            => (formatType == typeof(ICustomFormatter)) ? this : null;

        public string Format(string format, object arg, IFormatProvider formatProvider)
        {
            var props = arg.GetType().GetFields();

            var builder = new StringBuilder();
            builder.Append("{");
            foreach (var prop in props)
            {
                builder.Append(prop.Name);
                builder.Append(": ");
                builder.Append(prop.GetValue(arg).ToString());
                builder.Append(", ");
            }
            builder.Remove(builder.Length - ", ".Length, ", ".Length);
            builder.Append("}");
            return builder.ToString();
        }
    }
}

2021/3/10：この記事は別のブログで投稿した記事を移動したものです。