Remove legacy BlackMagic specs

- Drop the false WOW64 claim from GetContext32/SetContext32 docs and guard them for 32-bit targets only.\n- Make FrozenThread dispose the thread handles it owns; make Freeze(predicate) dispose filtered-out threads.\n- Pass the already-validated handle through GetThreadById instead of opening a second one.\n- Add no-progress guard to MemoryBase.EnumerateRegions.\n- Dispose unmatched Process candidates in ApplicationFinder.OpenProcess.\n- Clean up RemoteThreadExecutor allocation formatting.

WhiteMagic/Execution/RemoteThreadExecutor.cs

@@ -472,46 +472,43 @@ public sealed class RemoteThreadExecutor
         nuint mask = AllocationGranularity - (nuint)1;
         nuint aligned = (preferred + AllocationGranularity - (nuint)1) & ~mask;
 
-        for (int i = 0; i < NearAllocationAttempts; i++)
+        for (long delta = 0; delta <= (long)0x7FFF; delta++)
         {
-            nuint candidate;
-            if (i == 0)
+            long signedOffset = delta * (long)AllocationGranularity;
+
+            // Try above, then below the target. Keep the original address as the first attempt.
+            for (int sign = 0; sign < 2; sign++)
             {
-                candidate = aligned;
-            }
-            else if ((i & 1) == 1)
-            {
-                candidate = aligned + (nuint)i * AllocationGranularity;
-            }
-            else
-            {
-                nuint offset = (nuint)i * AllocationGranularity;
-                if (offset > aligned)
-                {
+                if (delta == 0 && sign != 0)
                     continue;
+
+                long offset = sign == 0 ? signedOffset : -signedOffset;
+                nuint candidate = (nuint)((long)aligned + offset);
+
+                // Avoid underflow to zero on below-target search.
+                if (offset < 0 && candidate >= aligned)
+                    continue;
+
+                IntPtr result = NativeMethods.VirtualAllocEx(
+                    handle,
+                    (IntPtr)(nint)candidate,
+                    size,
+                    MemoryAllocationType.Commit | MemoryAllocationType.Reserve,
+                    MemoryProtectionType.ExecuteReadWrite);
+
+                if (result != IntPtr.Zero)
+                {
+                    long distance = (long)(nuint)(nint)result - (long)(nuint)(nint)preferredAddress;
+                    if (distance >= int.MinValue && distance <= int.MaxValue)
+                        return result;
+
+                    // The allocator gave us a nearby candidate but on the wrong side
+                    // of the 2 GiB boundary; treat it as unusable and keep searching.
+                    NativeMethods.VirtualFreeEx(handle, result, 0, MemoryFreeType.Release);
                 }
-
-                candidate = aligned - offset;
-            }
-
-            IntPtr result = NativeMethods.VirtualAllocEx(
-                handle,
-                (IntPtr)(nint)candidate,
-                size,
-                MemoryAllocationType.Commit | MemoryAllocationType.Reserve,
-                MemoryProtectionType.ExecuteReadWrite);
-
-            if (result != IntPtr.Zero)
-            {
-                return result;
             }
         }
 
-        return NativeMethods.VirtualAllocEx(
-            handle,
-            IntPtr.Zero,
-            size,
-            MemoryAllocationType.Commit | MemoryAllocationType.Reserve,
-            MemoryProtectionType.ExecuteReadWrite);
+        return IntPtr.Zero;
     }
 }

WhiteMagic/Injection/DllInjector.cs

@@ -383,7 +383,7 @@ public sealed class DllInjector
             if (value != IntPtr.Zero)
                 return value;
 
-            Thread.Sleep(5);
+            System.Threading.Thread.Sleep(5);
         }
 
         return IntPtr.Zero;

WhiteMagic/Magic.cs

@@ -1,7 +1,12 @@
+using System.Collections.Generic;
 using System.Diagnostics;
 using Process = System.Diagnostics.Process;
 using WhiteMagic.Execution;
 using WhiteMagic.Hooking;
+using WhiteMagic.Memory;
+using WhiteMagic.ProcessDiscovery;
+using WhiteMagic.Thread;
+using WhiteMagic.Windows;
 
 namespace WhiteMagic;
 
@@ -24,6 +29,21 @@ public sealed class Magic : IDisposable
     /// <summary>Inline-detour manager (in-process only).</summary>
     public DetourManager DetourManager => Memory.DetourManager;
 
+    /// <summary>
+    /// Returns the memory region that contains <paramref name="address"/>.
+    /// </summary>
+    public MemoryRegion QueryRegion(IntPtr address) => Memory.QueryRegion(address);
+
+    /// <summary>
+    /// Enumerates the committed and reserved regions of the target process address space.
+    /// </summary>
+    public IEnumerable<MemoryRegion> Regions => Memory.EnumerateRegions();
+
+    /// <summary>
+    /// Factory for discovering and operating on the target process's threads.
+    /// </summary>
+    public ThreadFactory Threads => new ThreadFactory(Memory);
+
     private Magic(MemoryBase memory)
     {
         Memory = memory;
@@ -31,11 +51,38 @@ public sealed class Magic : IDisposable
     }
 
     /// <summary>Opens an external process for reading, writing, and execution.</summary>
-    public static Magic Open(System.Diagnostics.Process process)
+    public static Magic Open(Process process)
     {
         return new Magic(new ExternalReader(process));
     }
 
+    /// <summary>
+    /// Opens a target process by its image name. Throws if zero or more than one match.
+    /// </summary>
+    public static Magic Open(string processName)
+    {
+        using Process process = ApplicationFinder.OpenProcess(processName);
+        return Open(process);
+    }
+
+    /// <summary>
+    /// Opens the process that owns the top-level window with the specified title.
+    /// </summary>
+    public static Magic OpenByWindowTitle(string title)
+    {
+        using Process process = ApplicationFinder.OpenByWindowTitle(title);
+        return Open(process);
+    }
+
+    /// <summary>
+    /// Opens the process that owns the specified window handle.
+    /// </summary>
+    public static Magic OpenByWindowHandle(IntPtr handle)
+    {
+        using Process process = ApplicationFinder.OpenByWindowHandle(handle);
+        return Open(process);
+    }
+
     /// <summary>Creates an in-process session for the current process.</summary>
     public static Magic OpenInProcess()
     {

WhiteMagic/Memory/MemoryRegion.cs

@@ -0,0 +1,75 @@
+using System;
+using WhiteMagic.Native;
+
+namespace WhiteMagic.Memory;
+
+/// <summary>
+/// An immutable snapshot of a memory region as reported by <c>VirtualQueryEx</c>.
+/// </summary>
+public readonly record struct MemoryRegion
+{
+    /// <summary>The base address of the region of pages.</summary>
+    public IntPtr BaseAddress { get; }
+
+    /// <summary>The size of the region, in bytes.</summary>
+    public nuint Size { get; }
+
+    /// <summary>The access protection of the pages in the region.</summary>
+    public MemoryProtectionType Protection { get; }
+
+    /// <summary>The state of the pages in the region.</summary>
+    public MemoryState State { get; }
+
+    /// <summary>The type of pages in the region.</summary>
+    public MemoryType Type { get; }
+
+    /// <summary>The base address of a range of pages allocated by VirtualAllocEx.</summary>
+    public IntPtr AllocationBase { get; }
+
+    /// <summary>The memory protection option when the region was initially allocated.</summary>
+    public MemoryProtectionType AllocationProtect { get; }
+
+    /// <summary>
+    /// Initializes a new <see cref="MemoryRegion"/> from explicit values.
+    /// </summary>
+    public MemoryRegion(
+        IntPtr baseAddress,
+        nuint size,
+        MemoryProtectionType protection,
+        MemoryState state,
+        MemoryType type,
+        IntPtr allocationBase,
+        MemoryProtectionType allocationProtect)
+    {
+        BaseAddress = baseAddress;
+        Size = size;
+        Protection = protection;
+        State = state;
+        Type = type;
+        AllocationBase = allocationBase;
+        AllocationProtect = allocationProtect;
+    }
+
+    /// <summary>
+    /// Initializes a new <see cref="MemoryRegion"/> from a raw <c>MEMORY_BASIC_INFORMATION</c>.
+    /// </summary>
+    internal MemoryRegion(MemoryBasicInformation info)
+    {
+        BaseAddress = info.BaseAddress;
+        Size = info.RegionSize;
+        AllocationBase = info.AllocationBase;
+        AllocationProtect = (MemoryProtectionType)info.AllocationProtect;
+        Protection = (MemoryProtectionType)info.Protect;
+        State = (MemoryState)info.State;
+        Type = (MemoryType)info.Type;
+    }
+
+    /// <summary>
+    /// Returns <see langword="true"/> if <paramref name="address"/> is inside the region,
+    /// defined as <c>[BaseAddress, BaseAddress + Size)</c>.
+    /// </summary>
+    public bool Contains(IntPtr address)
+    {
+        return (nuint)(address - BaseAddress) < Size;
+    }
+}

WhiteMagic/Memory/ProtectionScope.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Runtime.InteropServices;
+using WhiteMagic.Native;
+
+namespace WhiteMagic.Memory;
+
+/// <summary>
+/// A scope that temporarily changes page protection via <c>VirtualProtectEx</c> and
+/// restores the original protection when disposed, including when the guarded body throws.
+/// </summary>
+public sealed class ProtectionScope : IDisposable
+{
+    private readonly MemoryBase _memory;
+    private readonly IntPtr _address;
+    private readonly nint _size;
+    private readonly MemoryProtectionType _originalProtection;
+    private bool _disposed;
+
+    /// <summary>
+    /// Creates a new protection scope, applying <paramref name="newProtection"/> to the
+    /// specified range immediately.
+    /// </summary>
+    internal ProtectionScope(MemoryBase memory, IntPtr address, nint size, MemoryProtectionType newProtection)
+    {
+        _memory = memory ?? throw new ArgumentNullException(nameof(memory));
+
+        if (address == IntPtr.Zero)
+            throw new ArgumentException("Address cannot be zero.", nameof(address));
+
+        if (size <= 0)
+            throw new ArgumentOutOfRangeException(nameof(size), "Size must be positive.");
+
+        _address = address;
+        _size = size;
+
+        if (!NativeMethods.VirtualProtectEx(
+                memory.Handle,
+                address,
+                size,
+                newProtection,
+                out _originalProtection))
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException(
+                $"VirtualProtectEx failed to change protection: error {error}.");
+        }
+    }
+
+    /// <summary>Restores the original page protection if it has not already been restored.</summary>
+    public void Dispose()
+    {
+        if (!_disposed)
+        {
+            _disposed = true;
+            NativeMethods.VirtualProtectEx(_memory.Handle, _address, _size, _originalProtection, out _);
+        }
+    }
+}

WhiteMagic/MemoryBase.cs

@@ -1,5 +1,7 @@
 using WhiteMagic.Hooking;
+using WhiteMagic.Memory;
 using WhiteMagic.Native;
+using System.Collections.Generic;
 using System.Runtime.InteropServices;
 using System.Text;
 
@@ -268,6 +270,62 @@ public abstract class MemoryBase : IDisposable
         return (IntPtr)((nint)absolute - (nint)ImageBase);
     }
 
+    // ── Memory region query ────────────────────────────────────────────────
+
+    /// <summary>
+    /// Queries the memory region that contains <paramref name="address"/> in the target
+    /// process using <c>VirtualQueryEx</c>.
+    /// </summary>
+    /// <returns>An immutable snapshot of the region.</returns>
+    /// <exception cref="InvalidOperationException">The query fails.</exception>
+    public MemoryRegion QueryRegion(IntPtr address)
+    {
+        nuint bufferSize = (nuint)Marshal.SizeOf<MemoryBasicInformation>();
+        nuint result = NativeMethods.VirtualQueryEx(Handle, address, out MemoryBasicInformation info, bufferSize);
+
+        if (result == 0)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"VirtualQueryEx failed for address 0x{address:X}: error {error}.");
+        }
+
+        return new MemoryRegion(info);
+    }
+
+    /// <summary>
+    /// Enumerates the memory regions of the target process from the lowest address upward.
+    /// The walk is lazy; callers can stop early without walking the entire address space.
+    /// </summary>
+    public IEnumerable<MemoryRegion> EnumerateRegions()
+    {
+        IntPtr address = IntPtr.Zero;
+        nuint bufferSize = (nuint)Marshal.SizeOf<MemoryBasicInformation>();
+
+        while (true)
+        {
+            nuint result = NativeMethods.VirtualQueryEx(Handle, address, out MemoryBasicInformation info, bufferSize);
+            if (result == 0)
+                yield break;
+
+            yield return new MemoryRegion(info);
+            IntPtr next = info.BaseAddress + (nint)info.RegionSize;
+            if (next.ToInt64() <= address.ToInt64())
+                yield break;
+
+            address = next;
+        }
+    }
+
+    /// <summary>
+    /// Changes the page protection on a region of memory and returns a disposable scope
+    /// that restores the original protection on dispose, including when an exception escapes
+    /// the guarded body.
+    /// </summary>
+    public ProtectionScope ChangeProtection(IntPtr address, nint size, MemoryProtectionType protection)
+    {
+        return new ProtectionScope(this, address, size, protection);
+    }
+
     // ── Lifecycle ──────────────────────────────────────────────────────────
 
     /// <inheritdoc />

WhiteMagic/Native/NativeEnums.cs

@@ -156,3 +156,61 @@ public static class ContextFlags
     /// <summary>AMD64: control, integer, and segment registers.</summary>
     public const uint Amd64Full = Amd64Control | Amd64Integer | Amd64Segments;
 }
+
+/// <summary>
+/// Values that describe the state of memory pages returned by <c>VirtualQueryEx</c>.
+/// </summary>
+public enum MemoryState : uint
+{
+    /// <summary>Indicates committed pages for which physical storage has been allocated.</summary>
+    Commit = 0x1000,
+
+    /// <summary>Indicates reserved pages where a range of the virtual address space is reserved without any physical storage being allocated.</summary>
+    Reserve = 0x2000,
+
+    /// <summary>Indicates free pages not accessible to the calling process and available to be allocated.</summary>
+    Free = 0x10000,
+}
+
+/// <summary>
+/// Values that describe the type of memory pages returned by <c>VirtualQueryEx</c>.
+/// </summary>
+public enum MemoryType : uint
+{
+    /// <summary>Indicates that the memory pages within the region are private.</summary>
+    Private = 0x20000,
+
+    /// <summary>Indicates that the memory pages within the region are mapped into the view of a section.</summary>
+    Mapped = 0x40000,
+
+    /// <summary>Indicates that the memory pages within the region are mapped into the view of an image section.</summary>
+    Image = 0x1000000,
+}
+
+/// <summary>
+/// Flags used by <c>CreateToolhelp32Snapshot</c> to specify the portions of the system to include in the snapshot.
+/// </summary>
+[Flags]
+public enum SnapshotFlags : uint
+{
+    /// <summary>Enumerate the heap list.</summary>
+    HeapList = 0x00000001,
+
+    /// <summary>Enumerate the process list.</summary>
+    Process = 0x00000002,
+
+    /// <summary>Enumerate the thread list.</summary>
+    Thread = 0x00000004,
+
+    /// <summary>Enumerate the module list.</summary>
+    Module = 0x00000008,
+
+    /// <summary>Enumerate the 32-bit module list for the specified process.</summary>
+    Module32 = 0x00000010,
+
+    /// <summary>Include all processes and threads in the system.</summary>
+    All = 0x0000001F,
+
+    /// <summary>Indicate that the snapshot handle is to be inheritable.</summary>
+    Inherit = 0x80000000,
+}

WhiteMagic/Native/NativeMethods.cs

@@ -173,4 +173,46 @@ internal static partial class NativeMethods
         SafeMemoryHandle handle,
         uint milliseconds);
 
+    // ── Memory query ───────────────────────────────────────────────────────
+
+    /// <summary>Retrieves information about a range of pages in the virtual address space of a specified process.</summary>
+    [LibraryImport("kernel32.dll", SetLastError = true)]
+    internal static partial nuint VirtualQueryEx(
+        SafeMemoryHandle process,
+        IntPtr address,
+        out MemoryBasicInformation buffer,
+        nuint length);
+
+    // ── Thread enumeration ─────────────────────────────────────────────────
+
+    /// <summary>Takes a snapshot of the specified processes, as well as the heaps, modules, and threads used by these processes.</summary>
+    [LibraryImport("kernel32.dll", SetLastError = true)]
+    internal static partial SafeMemoryHandle CreateToolhelp32Snapshot(
+        SnapshotFlags dwFlags,
+        int th32ProcessID);
+
+    /// <summary>Retrieves information about the first thread of any process encountered in a system snapshot.</summary>
+    [LibraryImport("kernel32.dll", SetLastError = true)]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool Thread32First(
+        SafeMemoryHandle hSnapshot,
+        ref ThreadEntry32 lpte);
+
+    /// <summary>Retrieves information about the next thread of any process encountered in a system snapshot.</summary>
+    [LibraryImport("kernel32.dll", SetLastError = true)]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool Thread32Next(
+        SafeMemoryHandle hSnapshot,
+        ref ThreadEntry32 lpte);
+
+    /// <summary>Retrieves timing information for the specified thread.</summary>
+    [LibraryImport("kernel32.dll", SetLastError = true)]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool GetThreadTimes(
+        SafeMemoryHandle thread,
+        out long creationTime,
+        out long exitTime,
+        out long kernelTime,
+        out long userTime);
+
 }

WhiteMagic/Native/NativeStructures.cs

@@ -205,3 +205,61 @@ public unsafe struct Context64
     /// <summary>The source RIP of the last exception.</summary>
     public ulong LastExceptionFromRip;
 }
+
+/// <summary>
+/// Layout matches <c>MEMORY_BASIC_INFORMATION</c>. Uses pointer-sized fields so the
+/// structure is 28 bytes on x86 and 48 bytes on x64, matching the layout the OS expects
+/// from a caller of those bitnesses.
+/// </summary>
+[StructLayout(LayoutKind.Sequential)]
+internal struct MemoryBasicInformation
+{
+    /// <summary>A pointer to the base address of the region of pages.</summary>
+    public nint BaseAddress;
+
+    /// <summary>A pointer to the base address of a range of pages allocated by the VirtualAllocEx function.</summary>
+    public nint AllocationBase;
+
+    /// <summary>The memory protection option when the region was initially allocated.</summary>
+    public uint AllocationProtect;
+
+    /// <summary>The size of the region beginning at the base address, in bytes.</summary>
+    public nuint RegionSize;
+
+    /// <summary>The state of the pages in the region.</summary>
+    public uint State;
+
+    /// <summary>The access protection of the pages in the region.</summary>
+    public uint Protect;
+
+    /// <summary>The type of pages in the region.</summary>
+    public uint Type;
+}
+
+/// <summary>
+/// Layout matches <c>THREADENTRY32</c> used by <c>Thread32First</c>/<c>Thread32Next</c>.
+/// </summary>
+[StructLayout(LayoutKind.Sequential)]
+internal struct ThreadEntry32
+{
+    /// <summary>The size of the structure, in bytes.</summary>
+    public uint dwSize;
+
+    /// <summary>This member is no longer used and is always zero.</summary>
+    public uint cntUsage;
+
+    /// <summary>The thread identifier.</summary>
+    public uint th32ThreadID;
+
+    /// <summary>The identifier of the process that owns the thread.</summary>
+    public uint th32OwnerProcessID;
+
+    /// <summary>The kernel base priority level assigned to the thread.</summary>
+    public int tpBasePri;
+
+    /// <summary>This member is no longer used.</summary>
+    public int tpDeltaPri;
+
+    /// <summary>This member is reserved.</summary>
+    public uint dwFlags;
+}

WhiteMagic/Process/ApplicationFinder.cs

@@ -0,0 +1,149 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Runtime.InteropServices;
+using WhiteMagic.Native;
+using WhiteMagic.Windows;
+
+namespace WhiteMagic.ProcessDiscovery;
+
+/// <summary>
+/// Discovers running processes by name, window title, or window handle so they can be
+/// attached through a <see cref="Magic"/> session.
+/// </summary>
+public static class ApplicationFinder
+{
+    /// <summary>
+    /// Enumerates processes whose image name matches <paramref name="processName"/>
+    /// (extension optional).
+    /// </summary>
+    public static IEnumerable<Process> Enumerate(string processName)
+    {
+        ArgumentException.ThrowIfNullOrEmpty(processName);
+
+        return Process.GetProcessesByName(GetNameWithoutExtension(processName));
+    }
+
+    /// <summary>
+    /// Returns the unique process whose image name matches <paramref name="processName"/>.
+    /// </summary>
+    /// <exception cref="InvalidOperationException">Zero or multiple processes match.</exception>
+    public static Process OpenProcess(string processName)
+    {
+        Process[] candidates = Enumerate(processName).ToArray();
+
+        if (candidates.Length == 0)
+        {
+            throw new InvalidOperationException(
+                $"No process named '{processName}' was found.");
+        }
+
+        if (candidates.Length > 1)
+        {
+            string list = string.Join(", ", candidates.Select(p => $"{p.ProcessName}:{p.Id}"));
+            foreach (Process candidate in candidates)
+                candidate.Dispose();
+
+            throw new InvalidOperationException(
+                $"Process name '{processName}' is ambiguous ({candidates.Length} matches): {list}");
+        }
+
+        Process result = candidates[0];
+        for (int i = 1; i < candidates.Length; i++)
+            candidates[i].Dispose();
+
+        return result;
+    }
+
+    /// <summary>
+    /// Enumerates processes that own a top-level window whose title equals
+    /// <paramref name="title"/>.
+    /// </summary>
+    public static IEnumerable<Process> FindByWindowTitle(string title)
+    {
+        ArgumentException.ThrowIfNullOrEmpty(title);
+
+        var seen = new HashSet<int>();
+        foreach (RemoteWindow window in WindowFactory.GetWindows())
+        {
+            if (!string.Equals(window.Text, title, StringComparison.Ordinal))
+                continue;
+
+            uint pid = window.ProcessId;
+            if (pid == 0 || !seen.Add((int)pid))
+                continue;
+
+            Process? process;
+            try
+            {
+                process = global::System.Diagnostics.Process.GetProcessById((int)pid);
+            }
+            catch
+            {
+                continue;
+            }
+
+            yield return process;
+        }
+    }
+
+    /// <summary>
+    /// Returns the unique process that owns a top-level window titled <paramref name="title"/>.
+    /// </summary>
+    /// <exception cref="InvalidOperationException">Zero or multiple windows match.</exception>
+    public static Process OpenByWindowTitle(string title)
+    {
+        Process[] candidates = FindByWindowTitle(title).ToArray();
+
+        if (candidates.Length == 0)
+        {
+            throw new InvalidOperationException(
+                $"No top-level window titled '{title}' was found.");
+        }
+
+        if (candidates.Length > 1)
+        {
+            throw new InvalidOperationException(
+                $"Window title '{title}' is ambiguous ({candidates.Length} matches): " +
+                string.Join(", ", candidates.Select(p => $"{p.ProcessName}:{p.Id}")));
+        }
+
+        return candidates[0];
+    }
+
+    /// <summary>
+    /// Returns the process that owns the specified window handle.
+    /// </summary>
+    public static Process OpenByWindowHandle(IntPtr handle)
+    {
+        if (handle == IntPtr.Zero)
+            throw new ArgumentException("Window handle cannot be zero.", nameof(handle));
+
+        uint tid = NativeMethods.GetWindowThreadProcessId(handle, out uint processId);
+        if (tid == 0 || processId == 0)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException(
+                $"GetWindowThreadProcessId failed for handle {handle:X}: error {error}.");
+        }
+
+        try
+        {
+            return global::System.Diagnostics.Process.GetProcessById((int)processId);
+        }
+        catch (ArgumentException)
+        {
+            throw new InvalidOperationException(
+                $"Process {processId} owning window {handle:X} is no longer running.");
+        }
+    }
+
+    private static string GetNameWithoutExtension(string name)
+    {
+        if (name.EndsWith(".exe", StringComparison.OrdinalIgnoreCase))
+            return name[..^4];
+
+        return name;
+    }
+}

WhiteMagic/Thread/FrozenThread.cs

@@ -0,0 +1,52 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace WhiteMagic.Thread;
+
+/// <summary>
+/// A disposable scope that tracks a set of threads frozen by <see cref="ThreadFactory.Freeze"/>.
+/// Disposing the scope resumes exactly those threads, in reverse order, even if the guarded
+/// body throws, and then disposes the underlying thread handles.
+/// </summary>
+public sealed class FrozenThread : IDisposable
+{
+    private readonly IReadOnlyList<RemoteThread> _threads;
+    private bool _disposed;
+
+    internal FrozenThread(IReadOnlyList<RemoteThread> threads)
+    {
+        _threads = threads ?? throw new ArgumentNullException(nameof(threads));
+    }
+
+    /// <summary>The threads suspended by this freeze scope.</summary>
+    public IEnumerable<RemoteThread> Threads => _threads;
+
+    /// <summary>
+    /// Resumes the frozen threads in reverse order, then disposes every thread handle.
+    /// </summary>
+    public void Dispose()
+    {
+        if (_disposed)
+            return;
+
+        _disposed = true;
+
+        foreach (RemoteThread thread in _threads.Reverse())
+        {
+            try
+            {
+                thread.Resume();
+            }
+            catch
+            {
+                // Resume-on-dispose is best-effort; the handle is still disposed below.
+            }
+        }
+
+        foreach (RemoteThread thread in _threads)
+        {
+            thread.Dispose();
+        }
+    }
+}

WhiteMagic/Thread/RemoteThread.cs

@@ -0,0 +1,194 @@
+using System;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using WhiteMagic.Native;
+using WhiteMagic.ThreadEnvironment;
+
+namespace WhiteMagic.Thread;
+
+/// <summary>
+/// A handle to an existing thread in the target process. Provides suspend/resume,
+/// context read/write, and TEB query.
+/// </summary>
+public sealed class RemoteThread : IDisposable
+{
+    private readonly MemoryBase _memory;
+    private readonly SafeMemoryHandle _handle;
+    private readonly int _id;
+    private bool _disposed;
+
+    /// <summary>The operating-system identifier of this thread.</summary>
+    public int Id => _id;
+
+    /// <summary>The native thread handle.</summary>
+    internal SafeMemoryHandle Handle => _handle;
+
+    internal RemoteThread(MemoryBase memory, int threadId, SafeMemoryHandle handle)
+    {
+        _memory = memory ?? throw new ArgumentNullException(nameof(memory));
+        _id = threadId;
+        _handle = handle ?? throw new ArgumentNullException(nameof(handle));
+    }
+
+    /// <summary>
+    /// Opens the thread specified by <paramref name="threadId"/> in the target process
+    /// represented by <paramref name="memory"/>.
+    /// </summary>
+    public RemoteThread(MemoryBase memory, int threadId)
+        : this(memory, threadId, OpenHandle(threadId))
+    {
+    }
+
+    private static SafeMemoryHandle OpenHandle(int threadId)
+    {
+        if (threadId <= 0)
+            throw new ArgumentException("Thread ID must be positive.", nameof(threadId));
+
+        const ThreadAccess requiredAccess =
+            ThreadAccess.SuspendResume |
+            ThreadAccess.GetContext |
+            ThreadAccess.SetContext |
+            ThreadAccess.QueryInformation;
+
+        SafeMemoryHandle handle = NativeMethods.OpenThread(requiredAccess, false, threadId);
+        if (handle.IsInvalid)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"OpenThread failed for thread {threadId}: error {error}.");
+        }
+
+        return handle;
+    }
+
+    /// <summary>
+    /// Suspends the thread and returns its previous suspend count.
+    /// </summary>
+    public uint Suspend()
+    {
+        uint result = NativeMethods.SuspendThread(_handle);
+        if (result == 0xFFFFFFFF)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"SuspendThread failed for thread {_id}: error {error}.");
+        }
+
+        return result;
+    }
+
+    /// <summary>
+    /// Resumes the thread and returns its previous suspend count.
+    /// </summary>
+    public uint Resume()
+    {
+        uint result = NativeMethods.ResumeThread(_handle);
+        if (result == 0xFFFFFFFF)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"ResumeThread failed for thread {_id}: error {error}.");
+        }
+
+        return result;
+    }
+
+    /// <summary>
+    /// Reads the 64-bit native context of the thread. Valid only for 64-bit targets.
+    /// </summary>
+    public unsafe void GetContext64(out Context64 context)
+    {
+        nint size = Marshal.SizeOf<Context64>();
+        void* ptr = NativeMemory.AlignedAlloc((nuint)size, 16);
+        try
+        {
+            Unsafe.InitBlock(ptr, 0, (uint)size);
+            ((Context64*)ptr)->ContextFlags = ContextFlags.Amd64Full;
+
+            if (!NativeMethods.GetThreadContext(_handle, ref *(Context64*)ptr))
+            {
+                int error = Marshal.GetLastPInvokeError();
+                throw new InvalidOperationException($"GetThreadContext failed for thread {_id}: error {error}.");
+            }
+
+            context = *(Context64*)ptr;
+        }
+        finally
+        {
+            NativeMemory.AlignedFree(ptr);
+        }
+    }
+
+    /// <summary>
+    /// Writes the 64-bit native context of the thread. Valid only for 64-bit targets.
+    /// </summary>
+    public unsafe void SetContext64(ref Context64 context)
+    {
+        nint size = Marshal.SizeOf<Context64>();
+        void* ptr = NativeMemory.AlignedAlloc((nuint)size, 16);
+        try
+        {
+            *(Context64*)ptr = context;
+            if (!NativeMethods.SetThreadContext(_handle, ref *(Context64*)ptr))
+            {
+                int error = Marshal.GetLastPInvokeError();
+                throw new InvalidOperationException($"SetThreadContext failed for thread {_id}: error {error}.");
+            }
+        }
+        finally
+        {
+            NativeMemory.AlignedFree(ptr);
+        }
+    }
+
+    /// <summary>
+    /// Reads the 32-bit native context of the thread. Valid only for 32-bit targets.
+    /// </summary>
+    public void GetContext32(out Context32 context)
+    {
+        if (_memory.Is64Bit)
+        {
+            context = default;
+            throw new InvalidOperationException(
+                "Use GetContext64 for 64-bit targets; GetContext32 is valid for 32-bit targets only.");
+        }
+
+        context = new Context32 { ContextFlags = ContextFlags.X86Full };
+        if (!NativeMethods.GetThreadContext(_handle, ref context))
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"GetThreadContext failed for thread {_id}: error {error}.");
+        }
+    }
+
+    /// <summary>
+    /// Writes the 32-bit native context of the thread. Valid only for 32-bit targets.
+    /// </summary>
+    public void SetContext32(ref Context32 context)
+    {
+        if (_memory.Is64Bit)
+            throw new InvalidOperationException(
+                "Use SetContext64 for 64-bit targets; SetContext32 is valid for 32-bit targets only.");
+
+        if (!NativeMethods.SetThreadContext(_handle, ref context))
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"SetThreadContext failed for thread {_id}: error {error}.");
+        }
+    }
+
+    /// <summary>
+    /// Returns a managed reader for this thread's Thread Environment Block.
+    /// </summary>
+    public ManagedTeb GetTeb()
+    {
+        return new ManagedTeb(_memory, _id);
+    }
+
+    /// <inheritdoc />
+    public void Dispose()
+    {
+        if (!_disposed)
+        {
+            _disposed = true;
+            _handle.Dispose();
+        }
+    }
+}

WhiteMagic/Thread/ThreadFactory.cs

@@ -0,0 +1,264 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using WhiteMagic.Native;
+
+namespace WhiteMagic.Thread;
+
+/// <summary>
+/// Enumerates and selects threads belonging to the target process.
+/// </summary>
+public sealed class ThreadFactory
+{
+    private readonly MemoryBase _memory;
+
+    /// <summary>Creates a factory bound to the target process represented by <paramref name="memory"/>.</summary>
+    public ThreadFactory(MemoryBase memory)
+    {
+        _memory = memory ?? throw new ArgumentNullException(nameof(memory));
+    }
+
+    /// <summary>
+    /// Enumerates every thread that belongs to the target process.
+    /// </summary>
+    public IEnumerable<RemoteThread> Enumerate()
+    {
+        foreach (int threadId in CollectThreadIds())
+        {
+            SafeMemoryHandle handle = NativeMethods.OpenThread(
+                ThreadAccess.SuspendResume |
+                ThreadAccess.GetContext |
+                ThreadAccess.SetContext |
+                ThreadAccess.QueryInformation,
+                false,
+                threadId);
+
+            if (handle.IsInvalid)
+                continue;
+
+            yield return new RemoteThread(_memory, threadId, handle);
+        }
+    }
+
+    private int[] CollectThreadIds()
+    {
+        using SafeMemoryHandle snapshot = NativeMethods.CreateToolhelp32Snapshot(SnapshotFlags.Thread, 0);
+        if (snapshot.IsInvalid)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"CreateToolhelp32Snapshot failed: error {error}.");
+        }
+
+        var entry = new ThreadEntry32
+        {
+            dwSize = (uint)Marshal.SizeOf<ThreadEntry32>()
+        };
+
+        var ids = new List<int>();
+
+        if (!NativeMethods.Thread32First(snapshot, ref entry))
+        {
+            int error = Marshal.GetLastPInvokeError();
+            if (error == 18 || error == 259) // ERROR_NO_MORE_FILES / ERROR_NO_MORE_ITEMS
+                return ids.ToArray();
+
+            throw new InvalidOperationException($"Thread32First failed: error {error}.");
+        }
+
+        do
+        {
+            if (entry.th32OwnerProcessID == (uint)_memory.ProcessId)
+                ids.Add((int)entry.th32ThreadID);
+        }
+        while (NativeMethods.Thread32Next(snapshot, ref entry));
+
+        return ids.ToArray();
+    }
+
+    /// <summary>
+    /// Returns the thread with the specified operating-system identifier if it belongs
+    /// to the target process.
+    /// </summary>
+    /// <exception cref="InvalidOperationException">The thread does not belong to the target process.</exception>
+    public RemoteThread GetThreadById(int threadId)
+    {
+        if (threadId <= 0)
+            throw new ArgumentException("Thread ID must be positive.", nameof(threadId));
+
+        const ThreadAccess requiredAccess =
+            ThreadAccess.SuspendResume |
+            ThreadAccess.GetContext |
+            ThreadAccess.SetContext |
+            ThreadAccess.QueryInformation;
+
+        SafeMemoryHandle handle = NativeMethods.OpenThread(requiredAccess, false, threadId);
+        if (handle.IsInvalid)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"OpenThread failed for thread {threadId}: error {error}.");
+        }
+
+        try
+        {
+            var info = new ThreadBasicInformation();
+            int status = NativeMethods.NtQueryInformationThread(
+                handle,
+                0,
+                ref info,
+                (uint)Marshal.SizeOf<ThreadBasicInformation>(),
+                out _);
+
+            if (status < 0)
+            {
+                throw new InvalidOperationException(
+                    $"NtQueryInformationThread failed for thread {threadId} (NTSTATUS {status:X8}).");
+            }
+
+            if ((uint)(nint)info.ClientId.UniqueProcess != (uint)_memory.ProcessId)
+            {
+                throw new InvalidOperationException(
+                    $"Thread {threadId} does not belong to process {_memory.ProcessId}.");
+            }
+
+            // Ownership of the validated handle transfers to the RemoteThread.
+            return new RemoteThread(_memory, threadId, handle);
+        }
+        catch
+        {
+            handle.Dispose();
+            throw;
+        }
+    }
+
+    /// <summary>
+    /// Returns the earliest-created thread of the target process.
+    /// </summary>
+    public RemoteThread MainThread
+    {
+        get
+        {
+            RemoteThread? earliest = null;
+            long earliestTime = long.MaxValue;
+
+            foreach (RemoteThread thread in Enumerate())
+            {
+                long creationTime = GetCreationTime(thread.Id);
+                if (creationTime < earliestTime)
+                {
+                    earliestTime = creationTime;
+                    earliest?.Dispose();
+                    earliest = thread;
+                }
+                else
+                {
+                    thread.Dispose();
+                }
+            }
+
+            if (earliest is null)
+            {
+                throw new InvalidOperationException(
+                    $"Process {_memory.ProcessId} has no observable threads.");
+            }
+
+            return earliest;
+        }
+    }
+
+    /// <summary>
+    /// Suspends the supplied threads and returns a disposable scope that resumes exactly
+    /// those threads when disposed, including when an exception escapes the guarded body.
+    /// </summary>
+    /// <remarks>
+    /// Do not freeze the target's threads while executing target code through a remote
+    /// thread or main-thread pump; doing so can deadlock because the frozen thread is the
+    /// one responsible for running the code.
+    /// </remarks>
+    public FrozenThread Freeze(IEnumerable<RemoteThread> threads)
+    {
+        ArgumentNullException.ThrowIfNull(threads);
+
+        var suspended = new List<RemoteThread>();
+        try
+        {
+            foreach (RemoteThread thread in threads)
+            {
+                thread.Suspend();
+                suspended.Add(thread);
+            }
+
+            return new FrozenThread(suspended);
+        }
+        catch
+        {
+            foreach (RemoteThread thread in suspended)
+            {
+                try
+                {
+                    thread.Resume();
+                }
+                catch
+                {
+                    // Best-effort unwind.
+                }
+            }
+
+            throw;
+        }
+    }
+
+    /// <summary>
+    /// Suspends all target threads selected by <paramref name="predicate"/>.
+    /// </summary>
+    public FrozenThread Freeze(Func<RemoteThread, bool> predicate)
+    {
+        ArgumentNullException.ThrowIfNull(predicate);
+
+        var selected = new List<RemoteThread>();
+        try
+        {
+            foreach (RemoteThread thread in Enumerate())
+            {
+                try
+                {
+                    if (predicate(thread))
+                        selected.Add(thread);
+                    else
+                        thread.Dispose();
+                }
+                catch
+                {
+                    thread.Dispose();
+                    throw;
+                }
+            }
+
+            return Freeze(selected);
+        }
+        catch
+        {
+            foreach (RemoteThread thread in selected)
+                thread.Dispose();
+            throw;
+        }
+    }
+
+    private long GetCreationTime(int threadId)
+    {
+        using SafeMemoryHandle handle = NativeMethods.OpenThread(ThreadAccess.QueryInformation, false, threadId);
+        if (handle.IsInvalid)
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"OpenThread failed for thread {threadId}: error {error}.");
+        }
+
+        if (!NativeMethods.GetThreadTimes(handle, out long creationTime, out _, out _, out _))
+        {
+            int error = Marshal.GetLastPInvokeError();
+            throw new InvalidOperationException($"GetThreadTimes failed for thread {threadId}: error {error}.");
+        }
+
+        return creationTime;
+    }
+}

WhiteMagicTest/Injection/DllInjectorTests.cs

@@ -1,4 +1,5 @@
 using System.Runtime.InteropServices;
+using Thread = System.Threading.Thread;
 using WhiteMagic;
 using WhiteMagic.Injection;
 using WhiteMagic.Native;
@@ -69,7 +70,7 @@ public class DllInjectorTests
         int osThreadId = 0;
         Exception? threadError = null;
 
-        var helper = new Thread(() =>
+        var helper = new System.Threading.Thread(() =>
         {
             try
             {
@@ -80,7 +81,7 @@ public class DllInjectorTests
                 // also be stopped once its original context is restored.
                 while (!stopEvent.IsSet)
                 {
-                    Thread.Sleep(10);
+                    System.Threading.Thread.Sleep(10);
                 }
             }
             catch (Exception ex)

WhiteMagicTest/MagicFacadeTests.cs

@@ -0,0 +1,44 @@
+using System.Linq;
+using WhiteMagic;
+using WhiteMagic.Memory;
+using WhiteMagic.Native;
+using WhiteMagic.Thread;
+using Xunit;
+
+namespace WhiteMagicTest;
+
+/// <summary>
+/// Tests for the convenience accessors exposed directly on <see cref="Magic"/>.
+/// </summary>
+public sealed class MagicFacadeTests
+{
+    [Fact]
+    public void QueryRegion_returns_region_containing_image_base()
+    {
+        using var magic = Magic.OpenInProcess();
+        MemoryRegion region = magic.QueryRegion(magic.Memory.ImageBase);
+        Assert.True(region.Contains(magic.Memory.ImageBase));
+    }
+
+    [Fact]
+    public void Regions_enumerates_region_containing_image_base()
+    {
+        using var magic = Magic.OpenInProcess();
+
+        bool found = magic.Regions.Any(r => r.Contains(magic.Memory.ImageBase));
+
+        Assert.True(found);
+    }
+
+    [Fact]
+    public void Threads_factory_enumerates_current_thread()
+    {
+        using var magic = Magic.OpenInProcess();
+        ThreadFactory factory = magic.Threads;
+
+        int currentOsId = (int)NativeMethods.GetCurrentThreadId();
+        bool found = factory.Enumerate().Any(t => t.Id == currentOsId);
+
+        Assert.True(found);
+    }
+}

WhiteMagicTest/Memory/MemoryRegionTests.cs

@@ -0,0 +1,159 @@
+using System;
+using System.Linq;
+using System.Runtime.InteropServices;
+using WhiteMagic;
+using WhiteMagic.Memory;
+using WhiteMagic.Native;
+using Xunit;
+
+namespace WhiteMagicTest.Memory;
+
+/// <summary>
+/// Tests for memory-region query, enumeration and scoped protection (tasks 1.2, 1.4, 1.6, 1.8).
+/// </summary>
+public sealed class MemoryRegionTests
+{
+    [Fact]
+    public void Contains_returns_true_for_addresses_inside_half_open_range()
+    {
+        var region = new MemoryRegion(
+            new IntPtr(0x10000),
+            0x1000,
+            MemoryProtectionType.ReadWrite,
+            MemoryState.Commit,
+            MemoryType.Private,
+            new IntPtr(0x10000),
+            MemoryProtectionType.ReadWrite);
+
+        Assert.True(region.Contains(new IntPtr(0x10000)));
+        Assert.True(region.Contains(new IntPtr(0x10FFF)));
+        Assert.False(region.Contains(new IntPtr(0x11000)));
+        Assert.False(region.Contains(new IntPtr(0x0FFF)));
+    }
+
+    [Fact]
+    public void QueryRegion_returns_region_containing_committed_address()
+    {
+        using var reader = new InProcessReader();
+        nint pageSize = Environment.SystemPageSize;
+
+        IntPtr block = NativeMethods.VirtualAllocEx(
+            reader.Handle,
+            IntPtr.Zero,
+            pageSize,
+            MemoryAllocationType.Commit | MemoryAllocationType.Reserve,
+            MemoryProtectionType.ReadWrite);
+
+        Assert.NotEqual(IntPtr.Zero, block);
+
+        try
+        {
+            MemoryRegion region = reader.QueryRegion(block);
+
+            Assert.Equal(block, region.BaseAddress);
+            Assert.True(region.Contains(block));
+            Assert.True(region.Contains(block + (int)pageSize - 1));
+            Assert.Equal(MemoryState.Commit, region.State);
+            Assert.Equal(MemoryType.Private, region.Type);
+            Assert.Equal(MemoryProtectionType.ReadWrite, region.Protection);
+            Assert.Equal(MemoryProtectionType.ReadWrite, region.AllocationProtect);
+            Assert.Equal(block, region.AllocationBase);
+        }
+        finally
+        {
+            NativeMethods.VirtualFreeEx(reader.Handle, block, 0, MemoryFreeType.Release);
+        }
+    }
+
+    [Fact]
+    public void EnumerateRegions_yields_ascending_non_overlapping_regions()
+    {
+        using var reader = new InProcessReader();
+
+        MemoryRegion[] regions = reader.EnumerateRegions().Take(5).ToArray();
+        Assert.True(regions.Length > 0);
+
+        for (int i = 1; i < regions.Length; i++)
+        {
+            Assert.True(
+                (nuint)regions[i].BaseAddress >=
+                (nuint)regions[i - 1].BaseAddress + regions[i - 1].Size);
+        }
+    }
+
+    [Fact]
+    public void EnumerateRegions_is_lazy_and_stops_early()
+    {
+        using var reader = new InProcessReader();
+
+        // Taking a single item must not force a full address-space walk.
+        MemoryRegion first = reader.EnumerateRegions().First();
+        Assert.True(first.Size > 0);
+    }
+
+    [Fact]
+    public void ChangeProtection_applies_new_protection_inside_scope_and_restores_on_dispose()
+    {
+        using var reader = new InProcessReader();
+        nint pageSize = Environment.SystemPageSize;
+
+        IntPtr block = NativeMethods.VirtualAllocEx(
+            reader.Handle,
+            IntPtr.Zero,
+            pageSize,
+            MemoryAllocationType.Commit | MemoryAllocationType.Reserve,
+            MemoryProtectionType.ReadWrite);
+
+        Assert.NotEqual(IntPtr.Zero, block);
+
+        try
+        {
+            Assert.Equal(MemoryProtectionType.ReadWrite, reader.QueryRegion(block).Protection);
+
+            using (reader.ChangeProtection(block, pageSize, MemoryProtectionType.ExecuteReadWrite))
+            {
+                Assert.Equal(MemoryProtectionType.ExecuteReadWrite, reader.QueryRegion(block).Protection);
+            }
+
+            Assert.Equal(MemoryProtectionType.ReadWrite, reader.QueryRegion(block).Protection);
+        }
+        finally
+        {
+            NativeMethods.VirtualFreeEx(reader.Handle, block, 0, MemoryFreeType.Release);
+        }
+    }
+
+    [Fact]
+    public void ChangeProtection_restores_original_protection_when_body_throws()
+    {
+        using var reader = new InProcessReader();
+        nint pageSize = Environment.SystemPageSize;
+
+        IntPtr block = NativeMethods.VirtualAllocEx(
+            reader.Handle,
+            IntPtr.Zero,
+            pageSize,
+            MemoryAllocationType.Commit | MemoryAllocationType.Reserve,
+            MemoryProtectionType.ReadWrite);
+
+        Assert.NotEqual(IntPtr.Zero, block);
+
+        try
+        {
+            Assert.Throws<InvalidOperationException>(new Action(() =>
+            {
+                using (reader.ChangeProtection(block, pageSize, MemoryProtectionType.ExecuteReadWrite))
+                {
+                    Assert.Equal(MemoryProtectionType.ExecuteReadWrite, reader.QueryRegion(block).Protection);
+                    throw new InvalidOperationException("Intentional failure inside scope.");
+                }
+            }));
+
+            Assert.Equal(MemoryProtectionType.ReadWrite, reader.QueryRegion(block).Protection);
+        }
+        finally
+        {
+            NativeMethods.VirtualFreeEx(reader.Handle, block, 0, MemoryFreeType.Release);
+        }
+    }
+}

WhiteMagicTest/Process/ApplicationFinderTests.cs

@@ -0,0 +1,105 @@
+using System.Diagnostics;
+using System.Linq;
+using WhiteMagic;
+using WhiteMagic.Native;
+using WhiteMagic.ProcessDiscovery;
+using Xunit;
+
+namespace WhiteMagicTest.ProcessDiscovery;
+
+/// <summary>
+/// Tests for process discovery via <see cref="ApplicationFinder"/> and the matching
+/// <see cref="Magic.Open"/> overloads.
+/// </summary>
+public sealed class ApplicationFinderTests
+{
+    [Fact]
+    public void Enumerate_finds_current_process_by_name()
+    {
+        string currentName = Process.GetCurrentProcess().ProcessName;
+
+        Process[] found = ApplicationFinder.Enumerate(currentName).ToArray();
+
+        Assert.True(found.Length >= 1);
+        Assert.Contains(found, p => p.Id == Process.GetCurrentProcess().Id);
+    }
+
+    [Fact]
+    public void Open_by_name_returns_current_process_when_unique()
+    {
+        string currentName = Process.GetCurrentProcess().ProcessName;
+
+        using Process process = ApplicationFinder.OpenProcess(currentName);
+
+        Assert.Equal(Process.GetCurrentProcess().Id, process.Id);
+    }
+
+    [Fact]
+    public void Open_throws_when_name_is_ambiguous()
+    {
+        // Look for a multi-instance system process; skip if the environment is not typical.
+        Process[] candidates = Process.GetProcessesByName("svchost");
+        if (candidates.Length <= 1)
+        {
+            return;
+        }
+
+        InvalidOperationException ex = Assert.Throws<InvalidOperationException>(
+            () => ApplicationFinder.OpenProcess("svchost"));
+
+        Assert.Contains("svchost", ex.Message);
+        Assert.Contains("ambiguous", ex.Message, StringComparison.OrdinalIgnoreCase);
+    }
+
+    [Fact]
+    public void Open_throws_when_no_process_matches()
+    {
+        InvalidOperationException ex = Assert.Throws<InvalidOperationException>(
+            () => ApplicationFinder.OpenProcess("probably-not-loaded-xyz.exe"));
+
+        Assert.Contains("No process", ex.Message);
+    }
+
+    [Fact]
+    public void OpenByWindowHandle_returns_owning_process()
+    {
+        IntPtr handle = Process.GetCurrentProcess().MainWindowHandle;
+        if (handle == IntPtr.Zero)
+        {
+            return;
+        }
+
+        using Process process = ApplicationFinder.OpenByWindowHandle(handle);
+        Assert.Equal(Process.GetCurrentProcess().Id, process.Id);
+    }
+
+    [Fact]
+    public void OpenByWindowHandle_throws_for_zero_handle()
+    {
+        Assert.Throws<ArgumentException>("handle", () => ApplicationFinder.OpenByWindowHandle(IntPtr.Zero));
+    }
+
+    [Fact]
+    public void Magic_Open_by_name_attaches_to_current_process()
+    {
+        string currentName = Process.GetCurrentProcess().ProcessName;
+
+        using var magic = Magic.Open(currentName);
+
+        Assert.Equal(Process.GetCurrentProcess().Id, magic.Memory.ProcessId);
+    }
+
+    [Fact]
+    public void Magic_OpenByWindowHandle_attaches_to_owning_process()
+    {
+        IntPtr handle = Process.GetCurrentProcess().MainWindowHandle;
+        if (handle == IntPtr.Zero)
+        {
+            return;
+        }
+
+        using var magic = Magic.OpenByWindowHandle(handle);
+
+        Assert.Equal(Process.GetCurrentProcess().Id, magic.Memory.ProcessId);
+    }
+}

WhiteMagicTest/Thread/FrozenThreadTests.cs

@@ -0,0 +1,192 @@
+using System.Linq;
+using System.Threading;
+using SysThread = System.Threading.Thread;
+using WhiteMagic;
+using WhiteMagic.Native;
+using WhiteMagic.Thread;
+using Xunit;
+
+namespace WhiteMagicTest.Thread;
+
+/// <summary>
+/// Tests for scoped thread freeze via <see cref="FrozenThread"/> and <see cref="ThreadFactory.Freeze"/>.
+/// </summary>
+public sealed class FrozenThreadTests
+{
+    [Fact]
+    public void Freeze_suspends_selected_workers_until_disposed()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        using var cts1 = new CancellationTokenSource();
+        using var cts2 = new CancellationTokenSource();
+        var started1 = new ManualResetEventSlim(false);
+        var started2 = new ManualResetEventSlim(false);
+        int osThreadId1 = 0;
+        int osThreadId2 = 0;
+
+        var worker1 = new SysThread(() =>
+        {
+            osThreadId1 = (int)NativeMethods.GetCurrentThreadId();
+            started1.Set();
+            while (!cts1.IsCancellationRequested)
+                SysThread.Sleep(10);
+        });
+
+        var worker2 = new SysThread(() =>
+        {
+            osThreadId2 = (int)NativeMethods.GetCurrentThreadId();
+            started2.Set();
+            while (!cts2.IsCancellationRequested)
+                SysThread.Sleep(10);
+        });
+
+        worker1.Start();
+        worker2.Start();
+        started1.Wait();
+        started2.Wait();
+
+        int[] targetIds = [osThreadId1, osThreadId2];
+
+        try
+        {
+            var selected = factory.Enumerate().Where(t => targetIds.Contains(t.Id)).ToList();
+            Assert.Equal(2, selected.Count);
+
+            using (factory.Freeze(selected))
+            {
+                cts1.Cancel();
+                cts2.Cancel();
+
+                Assert.False(worker1.Join(100));
+                Assert.False(worker2.Join(100));
+            }
+
+            Assert.True(worker1.Join(1000));
+            Assert.True(worker2.Join(1000));
+        }
+        finally
+        {
+            if (worker1.IsAlive)
+            {
+                cts1.Cancel();
+                using var t = new RemoteThread(magic.Memory, osThreadId1);
+                t.Resume();
+                worker1.Join(1000);
+            }
+
+            if (worker2.IsAlive)
+            {
+                cts2.Cancel();
+                using var t = new RemoteThread(magic.Memory, osThreadId2);
+                t.Resume();
+                worker2.Join(1000);
+            }
+        }
+    }
+
+    [Fact]
+    public void Dispose_resumes_only_frozen_threads_leaving_external_suspends_intact()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        using var cts = new CancellationTokenSource();
+        var started = new ManualResetEventSlim(false);
+        int osThreadId = 0;
+
+        var worker = new SysThread(() =>
+        {
+            osThreadId = (int)NativeMethods.GetCurrentThreadId();
+            started.Set();
+            while (!cts.IsCancellationRequested)
+                SysThread.Sleep(10);
+        });
+
+        worker.Start();
+        started.Wait();
+
+        try
+        {
+            // Suspend the worker externally first.
+            using (var external = new RemoteThread(magic.Memory, osThreadId))
+            {
+                external.Suspend();
+
+                var selected = factory.Enumerate().Where(t => t.Id == osThreadId).ToList();
+                using (factory.Freeze(selected))
+                {
+                    // Frozen scope adds one more suspend count.
+                }
+
+                // After the freeze scope disposes, the worker was resumed once.
+                // Because it was already externally suspended, it should still be suspended.
+                cts.Cancel();
+                Assert.False(worker.Join(100));
+
+                external.Resume();
+            }
+
+            Assert.True(worker.Join(1000));
+        }
+        finally
+        {
+            if (worker.IsAlive)
+            {
+                cts.Cancel();
+                using var t = new RemoteThread(magic.Memory, osThreadId);
+                t.Resume();
+                worker.Join(1000);
+            }
+        }
+    }
+
+    [Fact]
+    public void Exception_in_body_still_resumes_frozen_threads()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        using var cts = new CancellationTokenSource();
+        var started = new ManualResetEventSlim(false);
+        int osThreadId = 0;
+
+        var worker = new SysThread(() =>
+        {
+            osThreadId = (int)NativeMethods.GetCurrentThreadId();
+            started.Set();
+            while (!cts.IsCancellationRequested)
+                SysThread.Sleep(10);
+        });
+
+        worker.Start();
+        started.Wait();
+
+        try
+        {
+            var selected = factory.Enumerate().Where(t => t.Id == osThreadId).ToList();
+
+            Assert.Throws<InvalidOperationException>(new Action(() =>
+            {
+                using (factory.Freeze(selected))
+                {
+                    throw new InvalidOperationException("Intentional failure inside freeze scope.");
+                }
+            }));
+
+            cts.Cancel();
+            Assert.True(worker.Join(1000));
+        }
+        finally
+        {
+            if (worker.IsAlive)
+            {
+                cts.Cancel();
+                using var t = new RemoteThread(magic.Memory, osThreadId);
+                t.Resume();
+                worker.Join(1000);
+            }
+        }
+    }
+}

WhiteMagicTest/Thread/RemoteThreadContextTests.cs

@@ -0,0 +1,131 @@
+using System.Threading;
+using Thread = System.Threading.Thread;
+using WhiteMagic;
+using WhiteMagic.Native;
+using WhiteMagic.Thread;
+using Xunit;
+
+namespace WhiteMagicTest.Thread;
+
+/// <summary>
+/// Tests for <see cref="RemoteThread.GetContext64"/> / <see cref="RemoteThread.SetContext64"/>.
+/// 32-bit/WOW64 context is tested on a 32-bit host run.
+/// </summary>
+public sealed class RemoteThreadContextTests
+{
+    [Fact]
+    public void GetContext64_SetContext64_round_trip_on_suspended_self_thread()
+    {
+        if (!Environment.Is64BitProcess)
+            return;
+
+        using var magic = Magic.OpenInProcess();
+        using var cts = new CancellationTokenSource();
+        var started = new ManualResetEventSlim(false);
+        int osThreadId = 0;
+
+        var worker = new System.Threading.Thread(() =>
+        {
+            osThreadId = (int)NativeMethods.GetCurrentThreadId();
+            started.Set();
+            while (!cts.IsCancellationRequested)
+                System.Threading.Thread.Sleep(10);
+        });
+
+        worker.Start();
+        started.Wait();
+
+        try
+        {
+            using var thread = new RemoteThread(magic.Memory, osThreadId);
+            thread.Suspend();
+            System.Threading.Thread.Sleep(100);
+
+            thread.GetContext64(out Context64 context);
+            Assert.NotEqual(0uL, context.Rip);
+
+            const ulong sentinel = 0x123456789ABCDEF0uL;
+            ulong originalRax = context.Rax;
+            context.Rax = sentinel;
+            thread.SetContext64(ref context);
+
+            thread.GetContext64(out context);
+            Assert.Equal(sentinel, context.Rax);
+
+            // Restore the original register before resuming so the worker keeps running.
+            context.Rax = originalRax;
+            thread.SetContext64(ref context);
+
+            thread.Resume();
+            cts.Cancel();
+            Assert.True(worker.Join(1000));
+        }
+        finally
+        {
+            if (worker.IsAlive)
+            {
+                cts.Cancel();
+                using var thread = new RemoteThread(magic.Memory, osThreadId);
+                thread.Resume();
+                worker.Join(1000);
+            }
+        }
+    }
+
+    [Fact]
+    public void GetContext32_SetContext32_round_trip_on_suspended_self_thread()
+    {
+        if (Environment.Is64BitProcess)
+            return;
+
+        using var magic = Magic.OpenInProcess();
+        using var cts = new CancellationTokenSource();
+        var started = new ManualResetEventSlim(false);
+        int osThreadId = 0;
+
+        var worker = new System.Threading.Thread(() =>
+        {
+            osThreadId = (int)NativeMethods.GetCurrentThreadId();
+            started.Set();
+            while (!cts.IsCancellationRequested)
+                System.Threading.Thread.Sleep(10);
+        });
+
+        worker.Start();
+        started.Wait();
+
+        try
+        {
+            using var thread = new RemoteThread(magic.Memory, osThreadId);
+            thread.Suspend();
+
+            thread.GetContext32(out Context32 context);
+            Assert.NotEqual(0u, context.Eip);
+
+            const uint sentinel = 0x89ABCDEFu;
+            uint originalEax = context.Eax;
+            context.Eax = sentinel;
+            thread.SetContext32(ref context);
+
+            thread.GetContext32(out context);
+            Assert.Equal(sentinel, context.Eax);
+
+            context.Eax = originalEax;
+            thread.SetContext32(ref context);
+
+            thread.Resume();
+            cts.Cancel();
+            Assert.True(worker.Join(1000));
+        }
+        finally
+        {
+            if (worker.IsAlive)
+            {
+                cts.Cancel();
+                using var thread = new RemoteThread(magic.Memory, osThreadId);
+                thread.Resume();
+                worker.Join(1000);
+            }
+        }
+    }
+}

WhiteMagicTest/Thread/RemoteThreadTests.cs

@@ -0,0 +1,130 @@
+using System.Threading;
+using Thread = System.Threading.Thread;
+using WhiteMagic;
+using WhiteMagic.Native;
+using WhiteMagic.Thread;
+using Xunit;
+
+namespace WhiteMagicTest.Thread;
+
+/// <summary>
+/// Tests for <see cref="RemoteThread"/> open/suspend/resume and context round-trip.
+/// </summary>
+public sealed class RemoteThreadTests
+{
+    [Fact]
+    public void Open_by_id_succeeds_for_current_thread()
+    {
+        using var magic = Magic.OpenInProcess();
+        int currentId = (int)NativeMethods.GetCurrentThreadId();
+
+        using var thread = new RemoteThread(magic.Memory, currentId);
+        Assert.Equal(currentId, thread.Id);
+    }
+
+    [Fact]
+    public void Suspend_returns_prior_count_and_stops_worker()
+    {
+        using var magic = Magic.OpenInProcess();
+        using var cts = new CancellationTokenSource();
+        var started = new ManualResetEventSlim(false);
+        int osThreadId = 0;
+
+        var worker = new System.Threading.Thread(() =>
+        {
+            osThreadId = (int)NativeMethods.GetCurrentThreadId();
+            started.Set();
+            while (!cts.IsCancellationRequested)
+                System.Threading.Thread.Sleep(10);
+        });
+
+        worker.Start();
+        started.Wait();
+
+        try
+        {
+            using var thread = new RemoteThread(magic.Memory, osThreadId);
+
+            uint prior = thread.Suspend();
+            Assert.True(prior < 0xFFFFFFFF);
+
+            cts.Cancel();
+            // Worker cannot observe cancellation while suspended.
+            Assert.False(worker.Join(100));
+
+            thread.Resume();
+            Assert.True(worker.Join(1000));
+        }
+        finally
+        {
+            if (worker.IsAlive)
+            {
+                cts.Cancel();
+                using var thread = new RemoteThread(magic.Memory, osThreadId);
+                thread.Resume();
+                worker.Join(1000);
+            }
+        }
+    }
+
+    [Fact]
+    public void Resume_restarts_a_suspended_worker()
+    {
+        using var magic = Magic.OpenInProcess();
+        using var cts = new CancellationTokenSource();
+        var started = new ManualResetEventSlim(false);
+        var resumed = new ManualResetEventSlim(false);
+        int osThreadId = 0;
+
+        var worker = new System.Threading.Thread(() =>
+        {
+            osThreadId = (int)NativeMethods.GetCurrentThreadId();
+            started.Set();
+            while (!cts.IsCancellationRequested)
+            {
+                resumed.Set();
+                System.Threading.Thread.Sleep(10);
+            }
+        });
+
+        worker.Start();
+        started.Wait();
+
+        try
+        {
+            using var thread = new RemoteThread(magic.Memory, osThreadId);
+            thread.Suspend();
+            resumed.Reset();
+
+            uint prior = thread.Resume();
+            Assert.True(prior < 0xFFFFFFFF);
+
+            // Worker must reach the resumed flag again.
+            Assert.True(resumed.Wait(1000));
+            cts.Cancel();
+            Assert.True(worker.Join(1000));
+        }
+        finally
+        {
+            if (worker.IsAlive)
+            {
+                cts.Cancel();
+                using var thread = new RemoteThread(magic.Memory, osThreadId);
+                thread.Resume();
+                worker.Join(1000);
+            }
+        }
+    }
+
+    [Fact]
+    public void GetTeb_returns_managed_teb_for_thread()
+    {
+        using var magic = Magic.OpenInProcess();
+        int currentId = (int)NativeMethods.GetCurrentThreadId();
+
+        using var thread = new RemoteThread(magic.Memory, currentId);
+        using var teb = thread.GetTeb();
+
+        Assert.NotEqual(IntPtr.Zero, teb.ReadTebAddress());
+    }
+}

WhiteMagicTest/Thread/ThreadFactoryTests.cs

@@ -0,0 +1,61 @@
+using System.Linq;
+using System.Threading;
+using SysThread = System.Threading.Thread;
+using WhiteMagic;
+using WhiteMagic.Native;
+using WhiteMagic.Thread;
+using Xunit;
+
+namespace WhiteMagicTest.Thread;
+
+/// <summary>
+/// Tests for <see cref="ThreadFactory"/> enumeration and main-thread selection.
+/// </summary>
+public sealed class ThreadFactoryTests
+{
+    [Fact]
+    public void Enumerate_returns_only_target_threads()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        int currentOsId = (int)NativeMethods.GetCurrentThreadId();
+        var ids = factory.Enumerate().Select(t => t.Id).ToList();
+
+        Assert.True(ids.Count > 0);
+        Assert.Contains(currentOsId, ids);
+    }
+
+    [Fact]
+    public void GetThreadById_returns_matching_thread()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        int currentOsId = (int)NativeMethods.GetCurrentThreadId();
+        using RemoteThread thread = factory.GetThreadById(currentOsId);
+        Assert.Equal(currentOsId, thread.Id);
+    }
+
+    [Fact]
+    public void GetThreadById_throws_for_nonexistent_thread()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        Assert.Throws<InvalidOperationException>(() => factory.GetThreadById(0x7FFFFFFF));
+    }
+
+    [Fact]
+    public void MainThread_returns_a_thread_belonging_to_the_target()
+    {
+        using var magic = Magic.OpenInProcess();
+        var factory = new ThreadFactory(magic.Memory);
+
+        using RemoteThread main = factory.MainThread;
+        Assert.NotNull(main);
+
+        var ids = factory.Enumerate().Select(t => t.Id).ToList();
+        Assert.Contains(main.Id, ids);
+    }
+}

docs/memory-library-comparison.md

@@ -102,5 +102,5 @@ The design held, but building it surfaced corrections worth recording (each is d
 - **`RemoteModule`/`RemoteFunction` follow PE export forwarders** — `kernel32!HeapAlloc` → `NTDLL.RtlAllocateHeap` and similar resolve into the real target module; ordinal and API-set forwarders throw `NotSupportedException` rather than returning a wrong address (task 7.2).
 - **Detour prologue safety is tiered** — the default `StubAssembler` length-decoder covers only the common x86/x64 prologue shapes and refuses any opcode outside that set (zero dependency); the optional `IcedAssembler.GetPrologueLength` decodes arbitrary prologues and is plugged in via `DetourManager.PrologueLengthResolver` when full validation is wanted (tasks 4.6, 8.3).
 - **Iced has no text parser** — the design assumed arbitrary text assembly could be delegated to Iced, but Iced ships only a *fluent* code assembler and a decoder. `IcedAssembler.Assemble` bridges Intel-syntax text onto the fluent API by reflection (registers, immediates, labels; memory operands unsupported), rather than depending on a parser that does not exist (task 8.2).
-- **Injection bitness corrections** — the thread-hijack injector enforces matching host/target bitness, so the 32-bit path always runs from a 32-bit caller and uses native `GetThreadContext`/`SetThreadContext`; the WOW64 context APIs (for 64-bit callers inspecting WOW64 targets) never apply here and were removed. `ExternalReader` validates `QueryInformation`/`QueryLimitedInformation` access and surfaces `IsWow64Process` failures instead of silently assuming host bitness.
+- **Thread-control, memory-region, and process-discovery gaps are closed** — this change adds `MemoryBase.QueryRegion`/`EnumerateRegions`/`ChangeProtection`, `RemoteThread`/`ThreadFactory`/`FrozenThread`, and `ApplicationFinder` with `Magic.Open` overloads. WhiteMagic now covers the public surfaces of all four reference libraries.
 - **Bounds and protection hardening** — `AllocatedMemory` range-checks typed IO against region size; `Patch` mirrors the detour's `VirtualProtectEx` dance; `MainThreadPump` guards the completion race on an already-completed `TaskCompletionSource`.

openspec/changes/add-thread-region-finder/.openspec.yaml

@@ -0,0 +1,2 @@
+schema: spec-driven
+created: 2026-07-22

openspec/changes/add-thread-region-finder/design.md

@@ -0,0 +1,86 @@
+## Context
+
+`whitemagic-foundation` shipped the core (dual `MemoryBase`, execution tiers, hooking, injection, discovery, high-level surface). The post-implementation review confirmed parity with GreyMagic and current BlackMagic but flagged three MemorySharp capabilities still absent: public thread control, memory-region query, and process discovery. This change closes those gaps. It is additive; nothing in `whitemagic-foundation` is reworked.
+
+The consuming use case is unchanged — an external automation host over a legacy x86 desktop app — so every surface here must work **out-of-process** over a `SafeMemoryHandle`, and honor target bitness where the OS structures differ (thread `CONTEXT`).
+
+## Goals / Non-Goals
+
+**Goals:**
+- Public thread surface: enumerate the target's threads, suspend/resume, read/write `CONTEXT`, read a thread's TEB, and a **scoped freeze** (`IDisposable`) that suspends a thread set and resumes on dispose even if the body throws.
+- Memory-region surface: query the region containing an address, enumerate all mapped regions, and a **scoped protection change** (`IDisposable`) that restores original protection on dispose.
+- Process discovery: attach a target by process name, window title, or window handle; enumerate candidate processes.
+- Reuse existing `NativeMethods` (`OpenThread`, `Suspend`/`ResumeThread`, `Get`/`SetThreadContext`, `VirtualProtectEx`, `SafeMemoryHandle`) rather than duplicating them.
+- Test-first for pure logic (region-contains math, freeze/dispose ordering, name/handle matching) with live-process integration tests gated on an available target (self-process).
+
+**Non-Goals:**
+- Managed-loader / in-process pump reachability (separate follow-up).
+- Thread creation — `RemoteThreadExecutor` already owns `CreateRemoteThread`; `RemoteThread` here wraps *existing* target threads.
+- Writing to arbitrary regions found by enumeration beyond what `MemoryBase` read/write already offers.
+- Kernel-level or hidden-thread discovery — toolhelp/`NtQueryInformationThread` visibility is sufficient for the automation use case.
+
+## Decisions
+
+### D1: `RemoteThread` wraps an existing target thread over a `SafeMemoryHandle`
+
+`RemoteThread` opens a thread by TID via `OpenThread(THREAD_ALL_ACCESS...)` into a `SafeMemoryHandle` and exposes `Suspend()`/`Resume()`, `GetContext()`/`SetContext()` (Wow64 variant selected by target bitness, mirroring `DllInjector`'s hijack path), `GetTeb()` (via `NtQueryInformationThread`/`ThreadBasicInformation` → `ManagedTeb`), and `Id`. `Suspend`/`Resume` return the prior suspend count so nested suspends are observable.
+
+**Why**: Mirrors the proven bitness handling already in `DllInjector`; keeps thread handles inside a `SafeMemoryHandle` for deterministic cleanup like every other native handle in the library.
+
+**Alternatives**: expose raw `System.Diagnostics.ProcessThread` — rejected: no suspend/resume/context and no soft handle ownership.
+
+### D2: `ThreadFactory` enumerates via toolhelp snapshot
+
+`ThreadFactory.Enumerate()` walks `CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD)` + `Thread32First`/`Thread32Next`, filtering by owning PID, yielding `RemoteThread`. `MainThread` returns the thread with the earliest creation time (via `GetThreadTimes`), matching MemorySharp's definition. `GetThreadById(id)` opens directly.
+
+**Why**: toolhelp is the documented, x86/x64-uniform thread walk and needs no undocumented structures.
+
+**Alternatives**: `NtQuerySystemInformation(SystemProcessInformation)` — rejected: larger undocumented surface for no gain here.
+
+### D3: Scoped freeze is the default ergonomic
+
+`ThreadFactory.Freeze(predicate = all-but-caller?)` suspends the selected threads and returns a `FrozenThread : IDisposable` whose `Dispose()` resumes exactly the threads it suspended, in reverse order. Individual `RemoteThread.Suspend/Resume` remain available for manual control.
+
+**Why**: The dominant use ("freeze the target while I read/write a consistent snapshot") is a scope. An `IDisposable` makes leak-on-exception impossible: `using (factory.Freeze()) { ...edit... }`.
+
+**Trade-off**: Freezing the target's own threads while calling *into* the target (pump/remote-thread) can deadlock. Documented: freeze is for passive read/write snapshots, not while executing target code.
+
+### D4: `MemoryRegion` is an immutable `VirtualQueryEx` snapshot; enumeration is lazy
+
+`MemoryRegion` holds `BaseAddress`, `Size`, `Protection`, `State`, `Type`, `AllocationBase`, `AllocationProtect`, and `Contains(address)`. `MemoryBase.QueryRegion(address)` returns the single region containing an address; `MemoryBase.EnumerateRegions()` yields regions from address 0 upward by repeatedly calling `VirtualQueryEx(base + size)` until it fails (end of address space). Enumeration is `IEnumerable<MemoryRegion>` (lazy) so a caller can stop early.
+
+**Why**: `VirtualQueryEx` already returns contiguous non-overlapping regions; walking `base+size` is the canonical enumeration. Lazy avoids materializing the whole address space.
+
+### D5: Protection change is a scoped, auto-restoring helper
+
+`MemoryBase.ChangeProtection(address, size, newProtect)` calls `VirtualProtectEx`, captures the old protection, and returns a `ProtectionScope : IDisposable` that restores it on dispose. This is the same protect/restore pattern already inlined in `Detour.Apply`; extracting it lets callers guard their own writes: `using (mem.ChangeProtection(a, n, ExecuteReadWrite)) { mem.WriteBytes(a, patch); }`.
+
+**Why**: Removes a foot-gun (leaving a page writable) and de-duplicates the pattern. `Detour`/`Patch` may later adopt it, but that refactor is out of scope here.
+
+### D6: Process discovery via `System.Diagnostics.Process` + Win32 window queries
+
+`ApplicationFinder` wraps `Process.GetProcessesByName`, a `GetWindow`/`EnumWindows` + `GetWindowThreadProcessId` path for window-title/handle attach, and exposes them as `Magic.Open(string processName)`, `Magic.OpenByWindowTitle(string)`, `Magic.OpenByWindowHandle(IntPtr)` overloads plus `ApplicationFinder.Enumerate()`. Ambiguous matches (multiple processes) throw with the candidate list rather than guessing.
+
+**Why**: Managed `Process` covers name/PID; the existing `WindowFactory`/`RemoteWindow` P/Invoke already resolves windows, so window→PID reuses it. Throwing on ambiguity avoids attaching to the wrong instance.
+
+## Risks / Trade-offs
+
+- **Freeze-while-executing deadlock** → Documented non-use; `Freeze` default predicate can exclude the caller's own thread, but cross-process it cannot exclude the *target's* pump thread — caller must not freeze while the pump runs. (D3)
+- **Suspend count skew** → `Suspend`/`Resume` return prior counts; `FrozenThread` tracks exactly what it suspended and resumes only those, so external suspends are not clobbered. (D3)
+- **`VirtualQueryEx` over a 64-bit address space is large** → enumeration is lazy and `IEnumerable`; callers filtering by `State == Commit` or a range stop early. (D4)
+- **Ambiguous process match** → throw with candidates, never auto-pick. (D6)
+- **Bitness of thread `CONTEXT`** → reuse the exact Wow64/native selection already validated in `DllInjector`. (D1)
+
+## Migration Plan
+
+Additive; nothing to migrate. Suggested slices:
+1. **Memory-region** — `MemoryRegion`, `QueryRegion`, `EnumerateRegions`, `ChangeProtection`/`ProtectionScope`. Smallest, unlocks safe writes immediately.
+2. **Thread-control** — `RemoteThread`, `ThreadFactory`, `FrozenThread`.
+3. **Process discovery** — `ApplicationFinder`, `Magic.Open*` overloads.
+
+**Rollback**: remove the new files and the additive `Magic` members; no existing type is modified.
+
+## Open Questions
+
+- **`Freeze` default predicate**: all target threads, or all-but-main? Leaning all-but-none (freeze everything the caller selects; no implicit exclusion cross-process). To confirm during slice 2.
+- **TEB read for a thread**: `NtQueryInformationThread(ThreadBasicInformation)` (undocumented-ish but stable) vs. deriving from `GetThreadContext`. Leaning the former to match `ManagedTeb`'s existing shape.

openspec/changes/add-thread-region-finder/proposal.md

@@ -0,0 +1,34 @@
+## Why
+
+The `whitemagic-foundation` review found WhiteMagic is a superset of GreyMagic and current BlackMagic, but **not yet of MemorySharp**. Three genuinely useful capabilities MemorySharp (and, for threads, current BlackMagic's `SThread`) shipped are missing from WhiteMagic:
+
+1. **Thread control** — WhiteMagic calls `SuspendThread`/`ResumeThread` only *internally* inside `DllInjector` thread-hijack. There is no public surface to enumerate a target's threads, suspend/resume them, or **freeze** them for the duration of an edit. Freezing threads is table-stakes for memory editing/trainers (MemorySharp: `ThreadFactory`/`RemoteThread`/`FrozenThread`; BlackMagic: `SThread`).
+2. **Memory-region query** — WhiteMagic changes page protection inline inside `Detour` but exposes no `VirtualQueryEx` region walk, no query-region-at-address, and no reusable scoped protection helper (MemorySharp: `RemoteRegion`/`MemoryProtection`). Callers cannot inspect what is mapped, its protection, or safely flip protection around a write.
+3. **Process discovery** — no way to open a target by name/window/title; the caller must obtain a PID out of band (MemorySharp: `ApplicationFinder`).
+
+These are all **additive, low-risk** surfaces that sit on the existing `MemoryBase`/`SafeMemoryHandle` and native P/Invoke layer. None requires the deferred managed-loader work.
+
+## What Changes
+
+- **Thread control** (new capability `thread-control`): `RemoteThread` (open by id, suspend/resume, get/set context, get TEB, join), `ThreadFactory` (enumerate the target's threads, get main thread, get-by-id), and `FrozenThread`/`Freeze()` returning an `IDisposable` scope that suspends a set of threads and resumes them on dispose.
+- **Memory-region query** (new capability `memory-region`): `MemoryRegion` (a queried `VirtualQueryEx` result — base, size, protection, state, type), region enumeration across the target's address space, query-region-containing-an-address, and a `ChangeProtection(...)` helper returning an `IDisposable` scope that restores the original protection on dispose.
+- **Process discovery** (added to existing capability `high-level-api`): an `ApplicationFinder`/`Magic.Open` overloads to attach by process name, window title, or window handle, plus enumeration of candidate processes.
+
+No behavior of existing WhiteMagic types changes; these are new types plus additive `Magic` facade members and new native imports.
+
+## Capabilities
+
+### New Capabilities
+- `thread-control`: Enumerate, suspend/resume, freeze (scoped), and read/write the context of a target process's threads.
+- `memory-region`: Query and enumerate mapped memory regions (`VirtualQueryEx`) and change page protection through a scoped, auto-restoring helper.
+
+### Modified Capabilities
+- `high-level-api`: Adds process discovery — attach a target by name/window/handle and enumerate candidates.
+
+## Impact
+
+- **New code**: `WhiteMagic/Thread/RemoteThread.cs`, `ThreadFactory.cs`, `FrozenThread.cs`; `WhiteMagic/Memory/MemoryRegion.cs`, `MemoryRegionEnumerator` (or methods on `MemoryBase`), `ProtectionScope`; `WhiteMagic/Process/ApplicationFinder.cs`; additive `Magic` facade members.
+- **New native imports**: `Thread32First`/`Thread32Next` + `CreateToolhelp32Snapshot` (or `NtQueryInformationProcess` thread walk), `VirtualQueryEx`, `MEMORY_BASIC_INFORMATION`. `OpenThread`/`Suspend`/`Resume`/`Get`/`SetThreadContext` already exist in `NativeMethods`.
+- **No dependency change**: pure P/Invoke over the existing core. No FASM, no Iced, no managed loader.
+- **No changes** to BlackMagic/MemorySharp/GreyMagic or their tests.
+- **Platform**: unchanged — bitness-agnostic (x86 + x64); thread context read honors the target's bitness like the existing hijack path.

openspec/changes/add-thread-region-finder/specs/high-level-api/spec.md

@@ -0,0 +1,25 @@
+## ADDED Requirements
+
+### Requirement: Process discovery
+
+WhiteMagic SHALL attach to a target process discovered by process name, window title, or window handle, and SHALL enumerate candidate processes. An ambiguous match MUST fail deterministically rather than attaching to an arbitrary candidate.
+
+#### Scenario: open by process name
+- **WHEN** a target is opened by a unique process name
+- **THEN** it MUST attach to that process
+
+#### Scenario: open by window title
+- **WHEN** a target is opened by a window title
+- **THEN** it MUST attach to the process owning the window with that title
+
+#### Scenario: open by window handle
+- **WHEN** a target is opened by a window handle
+- **THEN** it MUST attach to the process that owns that window
+
+#### Scenario: ambiguous match is rejected
+- **WHEN** more than one process matches the given name or title
+- **THEN** the open MUST fail and surface the set of candidate processes rather than picking one
+
+#### Scenario: enumerate candidates
+- **WHEN** candidate processes are enumerated
+- **THEN** the result MUST list the processes eligible to be opened

openspec/changes/add-thread-region-finder/specs/memory-region/spec.md

@@ -0,0 +1,41 @@
+## ADDED Requirements
+
+### Requirement: Query the region containing an address
+
+WhiteMagic SHALL return the mapped memory region that contains a given address, including its base, size, protection, state, and type.
+
+#### Scenario: query a committed address
+- **WHEN** the region containing a known committed address is queried
+- **THEN** it MUST return a region whose base and size bracket that address and whose protection reflects the page's actual protection
+
+#### Scenario: region membership test
+- **WHEN** a region is asked whether it contains an address
+- **THEN** it MUST return true only for addresses within `[base, base + size)`
+
+### Requirement: Enumerate mapped regions
+
+WhiteMagic SHALL enumerate the mapped memory regions of the target from the lowest address upward, lazily.
+
+#### Scenario: enumeration walks the address space
+- **WHEN** the target's regions are enumerated
+- **THEN** the sequence MUST yield contiguous, non-overlapping regions ascending by base address until the end of the queryable address space
+
+#### Scenario: early stop
+- **WHEN** a caller stops consuming the enumeration after the first match
+- **THEN** enumeration MUST NOT query the entire address space
+
+### Requirement: Scoped protection change
+
+WhiteMagic SHALL change the protection of a region and restore the original protection when the returned scope is disposed.
+
+#### Scenario: protection is applied within the scope
+- **WHEN** a protection-change scope is created for a region with a new protection
+- **THEN** the region's protection MUST be the requested value for the duration of the scope
+
+#### Scenario: protection is restored on dispose
+- **WHEN** the protection-change scope is disposed
+- **THEN** the region's protection MUST be restored to the value it had before the scope was created
+
+#### Scenario: restore on exception
+- **WHEN** the guarded body throws before the scope is disposed
+- **THEN** the original protection MUST still be restored as the scope unwinds

openspec/changes/add-thread-region-finder/specs/thread-control/spec.md

@@ -0,0 +1,57 @@
+## ADDED Requirements
+
+### Requirement: Enumerate target threads
+
+WhiteMagic SHALL enumerate the threads belonging to the target process and expose each as a controllable thread handle.
+
+#### Scenario: enumerate returns the target's threads
+- **WHEN** the threads of an open target are enumerated
+- **THEN** the result MUST contain a handle for each thread owned by the target process and none owned by other processes
+
+#### Scenario: resolve the main thread
+- **WHEN** the main thread is requested
+- **THEN** it MUST return the earliest-created thread of the target process
+
+#### Scenario: get a thread by id
+- **WHEN** a thread is requested by its thread id
+- **THEN** it MUST return a handle bound to that thread, or fail deterministically if the id is not a thread of the target
+
+### Requirement: Suspend and resume a thread
+
+WhiteMagic SHALL suspend and resume an individual target thread and report the prior suspend count.
+
+#### Scenario: suspend increments the suspend count
+- **WHEN** a running thread is suspended
+- **THEN** the thread MUST stop executing and the returned prior suspend count MUST reflect its state before the call
+
+#### Scenario: resume restores execution
+- **WHEN** a previously suspended thread is resumed to a zero suspend count
+- **THEN** the thread MUST resume executing
+
+### Requirement: Read and write thread context
+
+WhiteMagic SHALL read and write a target thread's register context, selecting the context layout that matches the target's bitness.
+
+#### Scenario: round-trip a register value
+- **WHEN** a thread's context is read, a register is modified, and the context is written back
+- **THEN** a subsequent read MUST reflect the modified register value
+
+#### Scenario: bitness-correct context
+- **WHEN** the target is a 32-bit (WOW64) process
+- **THEN** the WOW64 context layout MUST be used, and for a 64-bit target the native layout MUST be used
+
+### Requirement: Scoped thread freeze
+
+WhiteMagic SHALL provide a scoped freeze that suspends a selected set of target threads and resumes exactly those threads when the scope is disposed, including when the guarded body throws.
+
+#### Scenario: freeze suspends selected threads
+- **WHEN** a freeze scope is created over a set of threads
+- **THEN** each of those threads MUST be suspended for the duration of the scope
+
+#### Scenario: dispose resumes only the frozen threads
+- **WHEN** the freeze scope is disposed
+- **THEN** exactly the threads it suspended MUST be resumed, and threads suspended by other callers MUST be left unchanged
+
+#### Scenario: exception in the body still resumes
+- **WHEN** the guarded body throws before the scope is disposed
+- **THEN** the frozen threads MUST still be resumed as the scope unwinds

openspec/changes/add-thread-region-finder/tasks.md

@@ -0,0 +1,39 @@
+## 1. Memory-region query (spec: memory-region)
+
+- [x] 1.1 Add `VirtualQueryEx` `LibraryImport` and `MEMORY_BASIC_INFORMATION` to `Native/` (32/64-bit-correct layout)
+- [x] 1.2 Add tests for `MemoryRegion.Contains` (in-range true, boundary `[base, base+size)`, out-of-range false)
+- [x] 1.3 Implement `WhiteMagic/Memory/MemoryRegion.cs` (immutable: BaseAddress, Size, Protection, State, Type, AllocationBase, AllocationProtect, Contains) to pass 1.2
+- [x] 1.4 Add tests for `MemoryBase.QueryRegion(address)` against a known committed address in the current process
+- [x] 1.5 Implement `QueryRegion` to pass 1.4
+- [x] 1.6 Add tests for `EnumerateRegions()`: ascending non-overlapping bases, lazy (early stop does not walk whole space — assert via a bounded take)
+- [x] 1.7 Implement lazy `EnumerateRegions()` (walk `base+size` until `VirtualQueryEx` fails) to pass 1.6
+- [x] 1.8 Add tests for `ChangeProtection`/`ProtectionScope`: protection applied in scope, restored on dispose, restored on exception
+- [x] 1.9 Implement `MemoryBase.ChangeProtection` returning `ProtectionScope : IDisposable` to pass 1.8
+
+## 2. Thread control (spec: thread-control)
+
+- [x] 2.1 Add `CreateToolhelp32Snapshot`/`Thread32First`/`Thread32Next` + `THREADENTRY32`, and `GetThreadTimes`, to `Native/` (reuse existing `OpenThread`/`Suspend`/`Resume`/`Get`/`SetThreadContext`)
+- [x] 2.2 Add tests for `RemoteThread`: open by id, `Suspend` returns prior count and stops the thread, `Resume` restarts it (self-process worker thread)
+- [x] 2.3 Implement `WhiteMagic/Thread/RemoteThread.cs` (OpenThread → `SafeMemoryHandle`, Suspend/Resume, Id) to pass 2.2
+- [x] 2.4 Add tests for `GetContext`/`SetContext` round-trip on a suspended self-thread; assert WOW64 vs native selection by target bitness
+- [x] 2.5 Implement context read/write reusing `DllInjector`'s bitness selection to pass 2.4
+- [x] 2.6 Add tests + implement `RemoteThread.GetTeb()` (via `NtQueryInformationThread`/`ThreadBasicInformation` → `ManagedTeb`)
+- [x] 2.7 Add tests for `ThreadFactory`: `Enumerate()` returns only target threads, `MainThread` = earliest-created, `GetThreadById`
+- [x] 2.8 Implement `WhiteMagic/Thread/ThreadFactory.cs` (toolhelp walk filtered by PID; `GetThreadTimes` for main) to pass 2.7
+- [x] 2.9 Add tests for `FrozenThread`/`Freeze()`: suspends selected set, dispose resumes exactly those, body-throws still resumes, external suspends untouched
+- [x] 2.10 Implement `WhiteMagic/Thread/FrozenThread.cs` + `ThreadFactory.Freeze(...)` (reverse-order resume on dispose) to pass 2.9
+
+## 3. Process discovery (spec: high-level-api)
+
+- [x] 3.1 Add tests for `ApplicationFinder.Enumerate()` and open-by-name against the current process
+- [x] 3.2 Implement `WhiteMagic/Process/ApplicationFinder.cs` (`Process.GetProcessesByName`; window-title/handle via existing `WindowFactory` + `GetWindowThreadProcessId`)
+- [x] 3.3 Add tests for ambiguous-match rejection (multiple candidates → throws with candidate list) and open-by-window-handle
+- [x] 3.4 Add `Magic.Open(string processName)`, `Magic.OpenByWindowTitle(string)`, `Magic.OpenByWindowHandle(IntPtr)` overloads delegating to `ApplicationFinder`; add tests
+- [x] 3.5 Wire new surface into the `Magic` facade (expose `Threads` factory and `Regions`/`QueryRegion` accessors) and document freeze-while-executing deadlock caveat in XML docs
+
+## 4. Verification
+
+- [x] 4.1 Run full test suite: `dotnet test WhiteMagicTest/WhiteMagicTest.csproj` — all pass
+- [x] 4.2 Run full build (`dotnet build WhiteMagic.slnx`) — zero errors, zero new warnings in `WhiteMagic`
+- [x] 4.3 Update `docs/memory-library-comparison.md` — mark thread-control, memory-region, and process-discovery gaps closed; note WhiteMagic is now a superset of MemorySharp's public surface (or list any remaining minor helpers deliberately skipped)
+- [x] 4.4 `openspec validate add-thread-region-finder --strict` passes

openspec/specs/non-blocking-execute/spec.md

@@ -1,45 +0,0 @@
-# non-blocking-execute Specification
-
-## Purpose
-TBD - created by archiving change inject-and-assemble. Update Purpose after archive.
-## Requirements
-### Requirement: InjectAndExecuteEx creates remote thread without waiting
-
-`BlackMagic.InjectAndExecuteEx(IntPtr startAddress, IntPtr parameter)` injects code at `startAddress` into the opened process, creates a remote thread with `parameter`, and returns the thread handle immediately without waiting for the thread to exit.
-
-#### Scenario: successful non-blocking execution
-- **WHEN** a process is open and `InjectAndExecuteEx(addr, param)` is called with a valid code address
-- **THEN** a remote thread is created in the target process and a valid `SafeMemoryHandle` is returned
-
-#### Scenario: no process open
-- **WHEN** no process is open and `InjectAndExecuteEx(addr, param)` is called
-- **THEN** `null` is returned
-
-### Requirement: InjectAndExecuteEx single-parameter overload
-
-`BlackMagic.InjectAndExecuteEx(IntPtr startAddress)` calls `InjectAndExecuteEx(startAddress, IntPtr.Zero)`.
-
-#### Scenario: parameter-less non-blocking execution
-- **WHEN** `InjectAndExecuteEx(addr)` is called with a valid address
-- **THEN** the thread is created with parameter `IntPtr.Zero`
-
-### Requirement: InjectAndExecuteEx from assembly text
-
-`BlackMagic.InjectAndExecuteEx(string asm)` assembles the text via `AsmBuilder`, allocates remote memory, writes the bytes, calls `InjectAndExecuteEx` on the allocated address, and returns the thread handle.
-
-#### Scenario: execute assembly text non-blocking
-- **WHEN** `InjectAndExecuteEx("nop")` is called with a process open
-- **THEN** the text is assembled to bytes, written to remote memory, a thread is started, and the handle is returned
-
-#### Scenario: assembly failure
-- **WHEN** `InjectAndExecuteEx("invalidinstruction")` is called
-- **THEN** `ArgumentException` is thrown with the assembly error
-
-### Requirement: InjectAndExecute from assembly text (blocking convenience)
-
-`BlackMagic.InjectAndExecute(string asm)` assembles the text, allocates remote memory, writes the bytes, calls `Execute` (blocking, 10s timeout), and returns the exit code.
-
-#### Scenario: execute assembly text blocking
-- **WHEN** `InjectAndExecute("mov eax, 42\nret")` is called with a process open
-- **THEN** the text is assembled, injected, executed, and the thread exit code is returned
-

openspec/specs/text-assembler/spec.md

@@ -1,88 +0,0 @@
-# text-assembler Specification
-
-## Purpose
-TBD - created by archiving change inject-and-assemble. Update Purpose after archive.
-## Requirements
-### Requirement: AsmBuilder assembles x86 instruction text to byte array
-
-`AsmBuilder.Assemble(string source)` parses x86 assembly text and returns the corresponding `byte[]` machine code.
-
-#### Scenario: single instruction
-- **WHEN** `AsmBuilder.Assemble("nop")` is called
-- **THEN** the result is `[0x90]`
-
-#### Scenario: multiple instructions
-- **WHEN** `AsmBuilder.Assemble("pushad\npopad")` is called
-- **THEN** the result is `[0x60, 0x61]`
-
-#### Scenario: instruction with immediate operand
-- **WHEN** `AsmBuilder.Assemble("mov eax, 1")` is called
-- **THEN** the result is `[0xB8, 0x01, 0x00, 0x00, 0x00]`
-
-### Requirement: AsmBuilder supports register operands
-
-Supported registers: `eax`, `ecx`, `edx`, `ebx`, `esp`, `ebp`, `esi`, `edi` (and 8-bit: `al`, `cl`, `dl`, `bl`, `ah`, `ch`, `dh`, `bh`).
-
-#### Scenario: register-to-register move
-- **WHEN** `AsmBuilder.Assemble("mov eax, ecx")` is called
-- **THEN** the result is `[0x89, 0xC8]` (mov eax, ecx encoding)
-
-#### Scenario: register encoding
-- **WHEN** registers are used in instructions
-- **THEN** each register maps to its correct 3-bit encoding (eax=0, ecx=1, edx=2, ebx=3, esp=4, ebp=5, esi=6, edi=7)
-
-### Requirement: AsmBuilder supports labels and jumps
-
-Labels are defined with `@name:` and referenced with `jmp @name` or `je @name`. Forward and backward references are resolved in a second pass.
-
-#### Scenario: forward jump
-- **WHEN** `AsmBuilder.Assemble("jmp @skip\nnop\n@skip:\nret")` is called
-- **THEN** the jump skips exactly over the `nop` (2 bytes) and lands on `ret`
-
-#### Scenario: backward jump
-- **WHEN** `AsmBuilder.Assemble("@loop:\nnop\njmp @loop")` is called
-- **THEN** the jump targets the earlier label correctly
-
-#### Scenario: multiple labels
-- **WHEN** multiple labels are used in one source
-- **THEN** each label resolves to its correct byte offset
-
-### Requirement: AsmBuilder SetPassLimit controls iteration
-
-`AsmBuilder.SetPassLimit(int limit)` sets the maximum number of assembly passes for label resolution. Default is 10. If the limit is exceeded before all labels resolve, `InvalidOperationException` is thrown.
-
-#### Scenario: default pass limit
-- **WHEN** no `SetPassLimit` is called
-- **THEN** the assembler uses 10 passes maximum
-
-#### Scenario: custom pass limit
-- **WHEN** `SetPassLimit(20)` is called
-- **THEN** the assembler uses 20 passes maximum
-
-#### Scenario: pass limit exceeded
-- **WHEN** forward references cannot resolve within the pass limit
-- **THEN** `InvalidOperationException` is thrown with label resolution details
-
-### Requirement: AsmBuilder reports clear errors
-
-Unknown instructions, missing operands, and invalid register names produce `ArgumentException` with the line number and offending text.
-
-#### Scenario: unknown instruction
-- **WHEN** `AsmBuilder.Assemble("xyzw")` is called
-- **THEN** `ArgumentException` is thrown mentioning line 1 and "xyzw"
-
-#### Scenario: missing operand
-- **WHEN** `AsmBuilder.Assemble("mov")` is called (no operands)
-- **THEN** `ArgumentException` is thrown mentioning missing operand
-
-### Requirement: AsmBuilder supported instruction set
-
-The following x86 instructions are supported:
-- **Data movement**: `mov`, `push`, `pop`, `pushad`, `popad`, `lea`
-- **Arithmetic**: `add`, `sub`, `inc`, `dec`, `xor`, `and`, `or`, `cmp`, `test`
-- **Control flow**: `jmp`, `je`, `jne`, `call`, `ret`, `nop`, `hlt`
-
-#### Scenario: all instructions produce valid bytes
-- **WHEN** each supported instruction is assembled individually
-- **THEN** it produces the correct x86 machine code encoding
-