added NativeLibraryHelper that helps us to identify 32bit and 64bit libraries

Author: jhabjan

Ghostscript.NET/Helpers/NativeLibraryHelper.cs

@@ -0,0 +1,136 @@
+//
+// NativeLibraryHelper.cs
+// This file is part of Ghostscript.NET library
+//
+// Author: Josip Habjan (habjan@gmail.com, http://www.linkedin.com/in/habjan) 
+// Copyright (c) 2013-2014 by Josip Habjan. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+using System;
+using System.IO;
+using Microsoft.WinAny;
+
+namespace Ghostscript.NET
+{
+    /// <summary>
+    /// Class that helps us to get various information about native libraries.
+    /// </summary>
+    internal class NativeLibraryHelper
+    {
+        /// <summary>
+        /// Gets the image file machine type.
+        /// </summary>
+        /// <param name="path">Native library path.</param>
+        /// <returns>Image file machine type.</returns>
+        public static ushort GetImageFileMachineType(string path)
+        {
+            using(FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
+            {
+                return GetImageFileMachineType(fs);
+            }
+        }
+
+        /// <summary>
+        /// Gets the image file machine type.
+        /// </summary>
+        /// <param name="buffer">Memory buffer representing native library.</param>
+        /// <returns>Image file machine type.</returns>
+        public static unsafe ushort GetImageFileMachineType(byte[] buffer)
+        {
+            fixed(byte *ptr = buffer)
+            {
+                using(UnmanagedMemoryStream ums = new UnmanagedMemoryStream(ptr, buffer.Length))
+                {
+                    return GetImageFileMachineType(ums);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Gets the image file machine type.
+        /// </summary>
+        /// <param name="srm">Stream representing native library.</param>
+        /// <returns>Image file machine type.</returns>
+        public static ushort GetImageFileMachineType(Stream srm)
+        {
+            using (BinaryReader reader = new BinaryReader(srm))
+            {
+                // seek to the IMAGE_DOS_HEADER->e_lfanew position
+                reader.BaseStream.Seek(0x3c, SeekOrigin.Begin);
+                // read out the value
+                uint e_lfanew = reader.ReadUInt32();
+                // seek the the file address of new exe header
+                reader.BaseStream.Seek(e_lfanew, SeekOrigin.Begin);
+                // read out the signature
+                uint signature = reader.ReadUInt32();
+                // check if it's a signature we can handle
+                if (signature != WinNT.IMAGE_NT_SIGNATURE)
+                {
+                    return WinNT.IMAGE_FILE_MACHINE_UNKNOWN;
+                }
+
+                // read out and return IMAGE_FILE_HEADER->Machine value
+                return reader.ReadUInt16();
+            }
+        }
+
+        /// <summary>
+        /// Gets if native library is compiled as 64bit library.
+        /// </summary>
+        /// <param name="path">Native library path.</param>
+        /// <returns>True if native library is compiled as 64 bit library.</returns>
+        public static bool Is64BitLibrary(string path)
+        {
+            ushort machine = GetImageFileMachineType(path);
+            return Is64BitMachineValue(machine);
+        }
+
+        /// <summary>
+        /// Gets if native library is compiled as 64bit library.
+        /// </summary>
+        /// <param name="buffer">Memory buffer representing native library.</param>
+        /// <returns>True if native library is compiled as 64 bit library.</returns>
+        public static bool Is64BitLibrary(byte[] buffer)
+        {
+            ushort machine = GetImageFileMachineType(buffer);
+            return Is64BitMachineValue(machine);
+        }
+
+        /// <summary>
+        /// Gets if machine value represents 64 bit machine.
+        /// </summary>
+        /// <param name="machine">IMAGE_FILE_HEADER->Machine value.</param>
+        private static bool Is64BitMachineValue(ushort machine)
+        {
+            switch(machine)
+            {
+                case WinNT.IMAGE_FILE_MACHINE_AMD64:
+                case WinNT.IMAGE_FILE_MACHINE_IA64:
+                    return true;
+                case WinNT.IMAGE_FILE_MACHINE_I386:
+                    return false;
+                default:
+                    return false;
+            }
+        }
+
+    }
+}