Magic the magic happen

Dalamud.Injector/RemotePinnedData.cs

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+using System;
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+using System.Text;
+
+using static Dalamud.Injector.NativeFunctions;
+
+namespace Dalamud.Injector
+{
+    /// <summary>
+    /// Pin an arbitrary string to a remote process.
+    /// </summary>
+    internal class RemotePinnedData : IDisposable
+    {
+        private readonly Process process;
+        private readonly byte[] data;
+        private readonly IntPtr allocAddr;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="RemotePinnedData"/> class.
+        /// </summary>
+        /// <param name="process">Process to write in.</param>
+        /// <param name="data">Data to write.</param>
+        public unsafe RemotePinnedData(Process process, byte[] data)
+        {
+            this.process = process;
+            this.data = data;
+
+            this.allocAddr = VirtualAllocEx(
+                this.process.Handle,
+                IntPtr.Zero,
+                this.data.Length,
+                AllocationType.Commit,
+                MemoryProtection.ReadWrite);
+
+            if (this.allocAddr == IntPtr.Zero || Marshal.GetLastWin32Error() != 0)
+            {
+                throw new Exception("Error allocating memory");
+            }
+
+            var result = WriteProcessMemory(
+                this.process.Handle,
+                this.allocAddr,
+                this.data,
+                this.data.Length,
+                out _);
+
+            if (!result || Marshal.GetLastWin32Error() != 0)
+            {
+                throw new Exception("Error writing memory");
+            }
+        }
+
+        /// <summary>
+        /// Gets the address of the pinned data.
+        /// </summary>
+        public IntPtr Address => this.allocAddr;
+
+        /// <inheritdoc/>
+        public void Dispose()
+        {
+            if (this.allocAddr == IntPtr.Zero)
+            {
+                return;
+            }
+
+            var result = VirtualFreeEx(
+                this.process.Handle,
+                this.allocAddr,
+                0,
+                AllocationType.Release);
+
+            if (!result || Marshal.GetLastWin32Error() != 0)
+            {
+                throw new Exception("Error freeing memory");
+            }
+        }
+    }
+}