Splitted the ProcessMonitor to have a cleaner separation of windows-specific and corss-platform code

src/Artemis.Core/Services/ProcessMonitoring/ProcessMonitor.Win32.cs

@@ -0,0 +1,231 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Globalization;
+using System.Runtime.InteropServices;
+
+namespace Artemis.Core.Services;
+
+// DarthAffe 31.08.2023: Based on how it's done in the framework:
+// https://github.com/dotnet/runtime/blob/f0463a98d105f26037f9d3e63213421a3a7d4dff/src/libraries/System.Diagnostics.Process/src/System/Diagnostics/ProcessManager.Win32.cs#L263
+public static unsafe partial class ProcessMonitor
+{
+    #region Native
+
+    [LibraryImport("ntdll.dll", EntryPoint = "NtQuerySystemInformation")]
+    private static partial uint NtQuerySystemInformation(int systemInformationClass, void* systemInformation, uint systemInformationLength, uint* returnLength);
+
+    [StructLayout(LayoutKind.Sequential)]
+    private struct SystemProcessInformation
+    {
+        // ReSharper disable MemberCanBePrivate.Local
+        public uint NextEntryOffset;
+        public uint NumberOfThreads;
+        private fixed byte Reserved1[48];
+        public UnicodeString ImageName;
+        public int BasePriority;
+        public nint UniqueProcessId;
+        private readonly nuint Reserved2;
+        public uint HandleCount;
+        public uint SessionId;
+        private readonly nuint Reserved3;
+        public nuint PeakVirtualSize;  // SIZE_T
+        public nuint VirtualSize;
+        private readonly uint Reserved4;
+        public nuint PeakWorkingSetSize;  // SIZE_T
+        public nuint WorkingSetSize;  // SIZE_T
+        private readonly nuint Reserved5;
+        public nuint QuotaPagedPoolUsage;  // SIZE_T
+        private readonly nuint Reserved6;
+        public nuint QuotaNonPagedPoolUsage;  // SIZE_T
+        public nuint PagefileUsage;  // SIZE_T
+        public nuint PeakPagefileUsage;  // SIZE_T
+        public nuint PrivatePageCount;  // SIZE_T
+        private fixed long Reserved7[6];
+        // ReSharper restore MemberCanBePrivate.Local
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    private struct UnicodeString
+    {
+        // ReSharper disable MemberCanBePrivate.Local
+        /// <summary>
+        /// Length in bytes, not including the null terminator, if any.
+        /// </summary>
+        public ushort Length;
+
+        /// <summary>
+        /// Max size of the buffer in bytes
+        /// </summary>
+        public ushort MaximumLength;
+        public nint Buffer;
+        // ReSharper restore MemberCanBePrivate.Local
+    }
+
+    [LibraryImport("kernel32.dll", EntryPoint = "QueryFullProcessImageNameW", StringMarshalling = StringMarshalling.Utf16)]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    private static partial bool QueryFullProcessImageName(nint hProcess, int dwFlags, [Out] char[] lpExeName, ref int lpdwSize);
+
+    [LibraryImport("kernel32.dll")]
+    private static partial nint OpenProcess(ProcessAccessFlags processAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, int processId);
+
+    [Flags]
+    private enum ProcessAccessFlags : uint
+    {
+        QueryLimitedInformation = 0x00001000
+    }
+
+    #endregion
+
+    #region Constants
+
+    private const int SYSTEM_PROCESS_INFORMATION = 5;
+    private const uint STATUS_INFO_LENGTH_MISMATCH = 0xC0000004;
+    private const int SYSTEM_PROCESS_ID = 4;
+    private const int IDLE_PROCESS_ID = 0;
+    private const int DEFAULT_BUFFER_SIZE = 1024 * 1024;
+
+    #endregion
+
+    #region Properties & Fields
+
+    private static void* _buffer;
+    private static uint _bufferSize;
+
+    #endregion
+
+    #region Methods
+
+    private static void InitializeBuffer()
+    {
+        _bufferSize = DEFAULT_BUFFER_SIZE;
+        _buffer = NativeMemory.Alloc(_bufferSize);
+    }
+
+    private static void FreeBuffer()
+    {
+        NativeMemory.Free(_buffer);
+        _bufferSize = 0;
+    }
+
+    private static void UpdateProcessInfosWin32(object? o)
+    {
+        lock (LOCK)
+        {
+            try
+            {
+                if (_bufferSize == 0) return;
+
+                while (true)
+                {
+                    uint actualSize = 0;
+                    uint status = NtQuerySystemInformation(SYSTEM_PROCESS_INFORMATION, _buffer, _bufferSize, &actualSize);
+
+                    if (status != STATUS_INFO_LENGTH_MISMATCH)
+                    {
+                        if ((int)status < 0)
+                            throw new InvalidOperationException("Error", new Win32Exception((int)status));
+
+                        UpdateProcessInfosWin32(new ReadOnlySpan<byte>(_buffer, (int)actualSize));
+                        return;
+                    }
+
+                    ResizeBuffer(GetEstimatedBufferSize(actualSize));
+                }
+            }
+            catch { /* Should we throw here? I guess no ... */ }
+        }
+    }
+
+    private static void UpdateProcessInfosWin32(ReadOnlySpan<byte> data)
+    {
+        int processInformationOffset = 0;
+
+        HashSet<int> processIds = new(_processes.Count);
+
+        while (true)
+        {
+            ref readonly SystemProcessInformation pi = ref MemoryMarshal.AsRef<SystemProcessInformation>(data[processInformationOffset..]);
+
+            int processId = pi.UniqueProcessId.ToInt32();
+            processIds.Add(processId);
+
+            if (!_processes.ContainsKey(processId))
+            {
+                string imageName;
+                string processName;
+                if (pi.ImageName.Buffer != nint.Zero)
+                {
+                    imageName = new ReadOnlySpan<char>(pi.ImageName.Buffer.ToPointer(), pi.ImageName.Length / sizeof(char)).ToString();
+                    processName = GetProcessShortName(imageName).ToString();
+                }
+                else
+                {
+                    imageName = string.Empty;
+                    processName = processId switch
+                    {
+                        SYSTEM_PROCESS_ID => "System",
+                        IDLE_PROCESS_ID => "Idle",
+                        _ => processId.ToString(CultureInfo.InvariantCulture) // use the process ID for a normal process without a name
+                    };
+                }
+
+                string executable = GetProcessFilename(processId);
+                ProcessInfo processInfo = new(processId, processName, imageName, executable);
+                _processes.Add(processId, processInfo);
+
+                OnProcessStarted(processInfo);
+            }
+
+            if (pi.NextEntryOffset == 0) break;
+            processInformationOffset += (int)pi.NextEntryOffset;
+        }
+
+        HandleStoppedProcesses(processIds);
+
+        LastUpdate = DateTime.Now;
+    }
+
+    private static string GetProcessFilename(int processId)
+    {
+        int capacity = byte.MaxValue;
+        char[] buffer = new char[capacity];
+        nint ptr = OpenProcess(ProcessAccessFlags.QueryLimitedInformation, false, processId);
+
+        return QueryFullProcessImageName(ptr, 0, buffer, ref capacity)
+                   ? new string(buffer, 0, capacity)
+                   : string.Empty;
+    }
+
+    // This function generates the short form of process name.
+    //
+    // This is from GetProcessShortName in NT code base.
+    // Check base\screg\winreg\perfdlls\process\perfsprc.c for details.
+    private static ReadOnlySpan<char> GetProcessShortName(ReadOnlySpan<char> name)
+    {
+        // Trim off everything up to and including the last slash, if there is one.
+        // If there isn't, LastIndexOf will return -1 and this will end up as a nop.
+        name = name[(name.LastIndexOf('\\') + 1)..];
+
+        // If the name ends with the ".exe" extension, then drop it, otherwise include
+        // it in the name.
+        if (name.EndsWith(".exe", StringComparison.OrdinalIgnoreCase))
+            name = name[..^4];
+
+        return name;
+    }
+
+    private static void ResizeBuffer(uint size)
+    {
+        NativeMemory.Free(_buffer);
+
+        _bufferSize = size;
+        _buffer = NativeMemory.Alloc(_bufferSize);
+    }
+
+    // allocating a few more kilo bytes just in case there are some new process
+    // kicked in since new call to NtQuerySystemInformation
+    private static uint GetEstimatedBufferSize(uint actualSize) => actualSize + (1024 * 10);
+
+    #endregion
+}

src/Artemis.Core/Services/ProcessMonitoring/ProcessMonitor.cs

@@ -1,105 +1,19 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
-using System.ComponentModel;
-using System.Diagnostics;
-using System.Globalization;
 using System.Linq;
-using System.Runtime.InteropServices;
 using System.Threading;
 
 namespace Artemis.Core.Services;
 
-// DarthAffe 31.08.2023: Based on how it's done in the framework:
+public static partial class ProcessMonitor
-// https://github.com/dotnet/runtime/blob/f0463a98d105f26037f9d3e63213421a3a7d4dff/src/libraries/System.Diagnostics.Process/src/System/Diagnostics/ProcessManager.Win32.cs#L263
-public static unsafe partial class ProcessMonitor
 {
-    #region Native
-
-    [LibraryImport("ntdll.dll", EntryPoint = "NtQuerySystemInformation")]
-    private static partial uint NtQuerySystemInformation(int systemInformationClass, void* systemInformation, uint systemInformationLength, uint* returnLength);
-
-    [StructLayout(LayoutKind.Sequential)]
-    private struct SystemProcessInformation
-    {
-        // ReSharper disable MemberCanBePrivate.Local
-        public uint NextEntryOffset;
-        public uint NumberOfThreads;
-        private fixed byte Reserved1[48];
-        public UnicodeString ImageName;
-        public int BasePriority;
-        public nint UniqueProcessId;
-        private readonly nuint Reserved2;
-        public uint HandleCount;
-        public uint SessionId;
-        private readonly nuint Reserved3;
-        public nuint PeakVirtualSize;  // SIZE_T
-        public nuint VirtualSize;
-        private readonly uint Reserved4;
-        public nuint PeakWorkingSetSize;  // SIZE_T
-        public nuint WorkingSetSize;  // SIZE_T
-        private readonly nuint Reserved5;
-        public nuint QuotaPagedPoolUsage;  // SIZE_T
-        private readonly nuint Reserved6;
-        public nuint QuotaNonPagedPoolUsage;  // SIZE_T
-        public nuint PagefileUsage;  // SIZE_T
-        public nuint PeakPagefileUsage;  // SIZE_T
-        public nuint PrivatePageCount;  // SIZE_T
-        private fixed long Reserved7[6];
-        // ReSharper restore MemberCanBePrivate.Local
-    }
-
-    [StructLayout(LayoutKind.Sequential)]
-    private struct UnicodeString
-    {
-        // ReSharper disable MemberCanBePrivate.Local
-        /// <summary>
-        /// Length in bytes, not including the null terminator, if any.
-        /// </summary>
-        public ushort Length;
-
-        /// <summary>
-        /// Max size of the buffer in bytes
-        /// </summary>
-        public ushort MaximumLength;
-        public nint Buffer;
-        // ReSharper restore MemberCanBePrivate.Local
-    }
-
-    [LibraryImport("kernel32.dll", EntryPoint = "QueryFullProcessImageNameW", StringMarshalling = StringMarshalling.Utf16)]
-    [return: MarshalAs(UnmanagedType.Bool)]
-    private static partial bool QueryFullProcessImageName(nint hProcess, int dwFlags, [Out] char[] lpExeName, ref int lpdwSize);
-
-    [LibraryImport("kernel32.dll")]
-    private static partial nint OpenProcess(ProcessAccessFlags processAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, int processId);
-
-    [Flags]
-    private enum ProcessAccessFlags : uint
-    {
-        QueryLimitedInformation = 0x00001000
-    }
-
-    #endregion
-
-    #region Constants
-
-    private const int SYSTEM_PROCESS_INFORMATION = 5;
-    private const uint STATUS_INFO_LENGTH_MISMATCH = 0xC0000004;
-    private const int SYSTEM_PROCESS_ID = 4;
-    private const int IDLE_PROCESS_ID = 0;
-    private const int DEFAULT_BUFFER_SIZE = 1024 * 1024;
-
-    #endregion
-
     #region Properties & Fields
 
     private static readonly object LOCK = new();
 
     private static Timer? _timer;
 
-    private static void* _buffer;
-    private static uint _bufferSize;
-
     private static Dictionary<int, ProcessInfo> _processes = new();
 
     public static ImmutableArray<ProcessInfo> Processes
@@ -160,10 +74,15 @@ public static unsafe partial class ProcessMonitor
         {
             if (_timer != null) return;
 
-            _bufferSize = DEFAULT_BUFFER_SIZE;
+            if (Environment.OSVersion.Platform == PlatformID.Win32NT)
-            _buffer = NativeMemory.Alloc(_bufferSize);
+            {
-
+                InitializeBuffer();
-            _timer = new Timer(Environment.OSVersion.Platform == PlatformID.Win32NT ? UpdateProcessInfosNative : UpdateProcessInfosSafe, null, TimeSpan.Zero, UpdateInterval);
+                _timer = new Timer(UpdateProcessInfosWin32, null, TimeSpan.Zero, UpdateInterval);
+            }
+            else
+            {
+                _timer = new Timer(UpdateProcessInfosCrossPlatform, null, TimeSpan.Zero, UpdateInterval);
+            }
         }
     }
 
@@ -174,174 +93,13 @@ public static unsafe partial class ProcessMonitor
             if (_timer == null) return;
 
             _timer.Dispose();
-
-            NativeMemory.Free(_buffer);
-            _bufferSize = 0;
             _timer = null;
+
+            if (Environment.OSVersion.Platform == PlatformID.Win32NT)
+                FreeBuffer();
         }
     }
 
-    #region Native ProcessInfo Update
-
-    private static void UpdateProcessInfosNative(object? o)
-    {
-        lock (LOCK)
-        {
-            try
-            {
-                if (_bufferSize == 0) return;
-
-                while (true)
-                {
-                    uint actualSize = 0;
-                    uint status = NtQuerySystemInformation(SYSTEM_PROCESS_INFORMATION, _buffer, _bufferSize, &actualSize);
-
-                    if (status != STATUS_INFO_LENGTH_MISMATCH)
-                    {
-                        if ((int)status < 0)
-                            throw new InvalidOperationException("Error", new Win32Exception((int)status));
-
-                        UpdateProcessInfosNative(new ReadOnlySpan<byte>(_buffer, (int)actualSize));
-                        return;
-                    }
-
-                    ResizeBuffer(GetEstimatedBufferSize(actualSize));
-                }
-            }
-            catch { /* Should we throw here? I guess no ... */ }
-        }
-    }
-
-    private static void UpdateProcessInfosNative(ReadOnlySpan<byte> data)
-    {
-        int processInformationOffset = 0;
-
-        HashSet<int> processIds = new(_processes.Count);
-
-        while (true)
-        {
-            ref readonly SystemProcessInformation pi = ref MemoryMarshal.AsRef<SystemProcessInformation>(data[processInformationOffset..]);
-
-            int processId = pi.UniqueProcessId.ToInt32();
-            processIds.Add(processId);
-
-            if (!_processes.ContainsKey(processId))
-            {
-                string imageName;
-                string processName;
-                if (pi.ImageName.Buffer != nint.Zero)
-                {
-                    imageName = new ReadOnlySpan<char>(pi.ImageName.Buffer.ToPointer(), pi.ImageName.Length / sizeof(char)).ToString();
-                    processName = GetProcessShortName(imageName).ToString();
-                }
-                else
-                {
-                    imageName = string.Empty;
-                    processName = processId switch
-                    {
-                        SYSTEM_PROCESS_ID => "System",
-                        IDLE_PROCESS_ID => "Idle",
-                        _ => processId.ToString(CultureInfo.InvariantCulture) // use the process ID for a normal process without a name
-                    };
-                }
-
-                string executable = GetProcessFilename(processId);
-                ProcessInfo processInfo = new(processId, processName, imageName, executable);
-                _processes.Add(processId, processInfo);
-
-                OnProcessStarted(processInfo);
-            }
-
-            if (pi.NextEntryOffset == 0) break;
-            processInformationOffset += (int)pi.NextEntryOffset;
-        }
-
-        HandleStoppedProcesses(processIds);
-
-        LastUpdate = DateTime.Now;
-    }
-
-    private static string GetProcessFilename(int processId)
-    {
-        int capacity = byte.MaxValue;
-        char[] buffer = new char[capacity];
-        nint ptr = OpenProcess(ProcessAccessFlags.QueryLimitedInformation, false, processId);
-
-        return QueryFullProcessImageName(ptr, 0, buffer, ref capacity)
-                   ? new string(buffer, 0, capacity)
-                   : string.Empty;
-    }
-
-    // This function generates the short form of process name.
-    //
-    // This is from GetProcessShortName in NT code base.
-    // Check base\screg\winreg\perfdlls\process\perfsprc.c for details.
-    private static ReadOnlySpan<char> GetProcessShortName(ReadOnlySpan<char> name)
-    {
-        // Trim off everything up to and including the last slash, if there is one.
-        // If there isn't, LastIndexOf will return -1 and this will end up as a nop.
-        name = name[(name.LastIndexOf('\\') + 1)..];
-
-        // If the name ends with the ".exe" extension, then drop it, otherwise include
-        // it in the name.
-        if (name.EndsWith(".exe", StringComparison.OrdinalIgnoreCase))
-            name = name[..^4];
-
-        return name;
-    }
-
-    private static void ResizeBuffer(uint size)
-    {
-        NativeMemory.Free(_buffer);
-
-        _bufferSize = size;
-        _buffer = NativeMemory.Alloc(_bufferSize);
-    }
-
-    // allocating a few more kilo bytes just in case there are some new process
-    // kicked in since new call to NtQuerySystemInformation
-    private static uint GetEstimatedBufferSize(uint actualSize) => actualSize + (1024 * 10);
-
-    #endregion
-
-    #region Safe ProcessInfo Update
-
-    private static void UpdateProcessInfosSafe(object? o)
-    {
-        lock (LOCK)
-        {
-            try
-            {
-                HashSet<int> processIds = new(_processes.Count);
-
-                foreach (Process process in Process.GetProcesses())
-                {
-                    int processId = process.Id;
-                    processIds.Add(processId);
-
-                    if (!_processes.ContainsKey(processId))
-                    {
-                        string imageName = string.Empty;
-                        string processName = process.ProcessName;
-                        string executable = string.Empty; //TODO DarthAffe 01.09.2023: Is there a crossplatform way to do this?
-
-                        ProcessInfo processInfo = new(processId, processName, imageName, executable);
-                        _processes.Add(processId, processInfo);
-
-                        OnProcessStarted(processInfo);
-                    }
-                }
-
-                HandleStoppedProcesses(processIds);
-
-                LastUpdate = DateTime.Now;
-            }
-            catch { /* Should we throw here? I guess no ... */ }
-        }
-    }
-
-    #endregion
-
     // ReSharper disable once SuggestBaseTypeForParameter
     private static void HandleStoppedProcesses(HashSet<int> currentProcessIds)
     {

src/Artemis.Core/Services/ProcessMonitoring/ProcessMonitor.xPlatform.cs

@@ -0,0 +1,46 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace Artemis.Core.Services;
+
+public static partial class ProcessMonitor
+{
+    #region Methods
+
+    private static void UpdateProcessInfosCrossPlatform(object? o)
+    {
+        lock (LOCK)
+        {
+            try
+            {
+                HashSet<int> processIds = new(_processes.Count);
+
+                foreach (Process process in Process.GetProcesses())
+                {
+                    int processId = process.Id;
+                    processIds.Add(processId);
+
+                    if (!_processes.ContainsKey(processId))
+                    {
+                        string imageName = string.Empty;
+                        string processName = process.ProcessName;
+                        string executable = string.Empty; //TODO DarthAffe 01.09.2023: Is there a crossplatform way to do this?
+
+                        ProcessInfo processInfo = new(processId, processName, imageName, executable);
+                        _processes.Add(processId, processInfo);
+
+                        OnProcessStarted(processInfo);
+                    }
+                }
+
+                HandleStoppedProcesses(processIds);
+
+                LastUpdate = DateTime.Now;
+            }
+            catch { /* Should we throw here? I guess no ... */ }
+        }
+    }
+
+    #endregion
+}