子プロセスを起動するようなアプリケーションでは、ゾンビ化しないように確実に子プロセスが終了するようにしたい。
やり方自体は枯れた情報だけどQiitaに記事がなかったし、C/C++だと例があるがC#だとあまり日本語での情報があまり引掛からないので書いてみた。
大まかな処理
-
CreateJobObject関数でジョブオブジェクトを作成する。 -
SetInformationJobObject関数でJOBOBJECT_BASIC_LIMIT_INFORMATION::LimitFlagsにJOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSEを設定する。 -
AssignProcessToJobObject関数でジョブに子プロセスを紐付ける。 - 子プロセスが必要な期間、ジョブオブジェクトのハンドルを保持する。(開放しなければプロセス終了時に開放される)
注意点としては、 JOBOBJECT_BASIC_LIMIT_INFORMATION::LimitFlags でフラグを設定するのに、SetInformationJobObject 関数では JobObjectExtendedLimitInformationと JOBOBJECT_EXTENDED_LIMIT_INFORMATION 構造体を使用しなければならないこと。
使い方
using System;
using System.Diagnostics;
using JobObjectSharp;
namespace JobObjectSharp.Sample
{
class Program
{
static void Main(string[] args)
{
var process = Process.Start("notepad.exe");
process.WaitForInputIdle();
using (var job = JobObject.CreateAsKillOnJobClose())
{
job.AssignProcess(process);
} // notepad.exe killed
}
}
}
おすすめはしないが、Interop.Excelに応用するとしたらApplicationClass.HwndからGetWindowThreadProcessId関数でプロセスIDを取得すれば対応できるはず。
ソースコード
JobObject.cs
using System;
using System.ComponentModel;
using System.Runtime.InteropServices;
using Microsoft.Win32.SafeHandles;
namespace JobObjectSharp
{
public class JobObject : IDisposable
{
public static JobObject CreateAsKillOnJobClose()
{
var job = new JobObject();
var jobInfo = new JOBOBJECT_EXTENDED_LIMIT_INFORMATION()
{
BasicLimitInformation = new JOBOBJECT_BASIC_LIMIT_INFORMATION()
{
LimitFlags = JobObjectLimit.KillOnJobClose
},
};
var size = Marshal.SizeOf(typeof(JOBOBJECT_EXTENDED_LIMIT_INFORMATION));
if (!Native.SetInformationJobObject(job.SafeHandle, JobObjectInfoClass.ExtendedLimitInformation, ref jobInfo, size))
{
throw new Win32Exception();
}
return job;
}
private JobObject(SafeJobHandle safeHandle) => SafeHandle = safeHandle;
private JobObject(string name = null)
{
SafeHandle = Native.CreateJobObject(IntPtr.Zero, name);
if (SafeHandle.IsInvalid)
throw new Win32Exception();
}
public void AssignProcess(int processId)
{
using (var hProcess = Native.OpenProcess(ProcessAccessFlags.SetQuota | ProcessAccessFlags.Terminate, false, processId))
{
AssignProcess(hProcess);
}
}
public void AssignProcess(System.Diagnostics.Process process)
=> AssignProcess(process.SafeHandle);
public void AssignProcess(SafeProcessHandle hProcess)
{
if (hProcess.IsInvalid)
throw new ArgumentException(nameof(hProcess));
if (!Native.AssignProcessToJobObject(SafeHandle, hProcess))
{
throw new Win32Exception();
}
}
public void Terminate(int exitCode = 0)
{
if (!Native.TerminateJobObject(SafeHandle, exitCode))
{
throw new Win32Exception();
}
}
public SafeJobHandle SafeHandle { get; private set; }
#region IDisposable Support
private bool _disposedValue = false;
protected virtual void Dispose(bool disposing)
{
if (!_disposedValue)
{
if (disposing)
{
SafeHandle.Dispose();
}
_disposedValue = true;
}
}
public void Dispose()
{
Dispose(true);
}
#endregion
}
public sealed class SafeJobHandle : SafeHandleZeroOrMinusOneIsInvalid
{
internal static SafeJobHandle InvalidHandle => new SafeJobHandle(IntPtr.Zero);
private SafeJobHandle()
: base(true)
{
}
internal SafeJobHandle(IntPtr handle)
: base(true) => base.SetHandle(handle);
protected override bool ReleaseHandle() => Native.CloseHandle(base.handle);
}
[Flags]
enum ProcessAccessFlags : uint
{
None = 0,
All = 0x001F0FFF,
Terminate = 0x00000001,
CreateThread = 0x00000002,
VirtualMemoryOperation = 0x00000008,
VirtualMemoryRead = 0x00000010,
VirtualMemoryWrite = 0x00000020,
DuplicateHandle = 0x00000040,
CreateProcess = 0x000000080,
SetQuota = 0x00000100,
SetInformation = 0x00000200,
QueryInformation = 0x00000400,
QueryLimitedInformation = 0x00001000,
Synchronize = 0x00100000,
}
enum JobObjectInfoClass
{
AssociateCompletionPortInformation = 7,
BasicLimitInformation = 2,
BasicUIRestrictions = 4,
EndOfJobTimeInformation = 6,
ExtendedLimitInformation = 9,
SecurityLimitInformation = 5,
GroupInformation = 11,
}
[Flags]
enum JobObjectLimit : uint
{
None = 0,
// Basic Limits
Workingset = 0x00000001,
ProcessTime = 0x00000002,
JobTime = 0x00000004,
ActiveProcess = 0x00000008,
Affinity = 0x00000010,
PriorityClass = 0x00000020,
PreserveJobTime = 0x00000040,
SchedulingClass = 0x00000080,
// Extended Limits
ProcessMemory = 0x00000100,
JobMemory = 0x00000200,
DieOnUnhandledException = 0x00000400,
BreakawayOk = 0x00000800,
SilentBreakawayOk = 0x00001000,
KillOnJobClose = 0x00002000,
SubsetAffinity = 0x00004000,
// Notification Limits
JobReadBytes = 0x00010000,
JobWriteBytes = 0x00020000,
RateControl = 0x00040000,
}
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_BASIC_LIMIT_INFORMATION
{
public Int64 PerProcessUserTimeLimit;
public Int64 PerJobUserTimeLimit;
public JobObjectLimit LimitFlags;
public UIntPtr MinimumWorkingSetSize;
public UIntPtr MaximumWorkingSetSize;
public UInt32 ActiveProcessLimit;
public Int64 Affinity;
public UInt32 PriorityClass;
public UInt32 SchedulingClass;
}
[StructLayout(LayoutKind.Sequential)]
struct IO_COUNTERS
{
public UInt64 ReadOperationCount;
public UInt64 WriteOperationCount;
public UInt64 OtherOperationCount;
public UInt64 ReadTransferCount;
public UInt64 WriteTransferCount;
public UInt64 OtherTransferCount;
}
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_EXTENDED_LIMIT_INFORMATION
{
public JOBOBJECT_BASIC_LIMIT_INFORMATION BasicLimitInformation;
public IO_COUNTERS IoInfo;
public UIntPtr ProcessMemoryLimit;
public UIntPtr JobMemoryLimit;
public UIntPtr PeakProcessMemoryUsed;
public UIntPtr PeakJobMemoryUsed;
}
static class Native
{
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool SetInformationJobObject(SafeJobHandle hJob,
JobObjectInfoClass JobObjectInfoClass,
ref JOBOBJECT_EXTENDED_LIMIT_INFORMATION lpJobObjectInfo,
int cbJobObjectInfoLength);
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool AssignProcessToJobObject(SafeJobHandle hJob, SafeProcessHandle hProcess);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern SafeProcessHandle OpenProcess(
ProcessAccessFlags processAccess,
bool bInheritHandle,
int processId);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern SafeJobHandle CreateJobObject(IntPtr lpJobAttributes, string lpName);
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public extern static bool CloseHandle(IntPtr handle);
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public extern static bool TerminateJobObject(SafeJobHandle handle, int uExitCode);
}
}