AForge.NET open source framework

// AForge Library
//
// Copyright � Andrew Kirillov, 2005-2006
// andrew.kirillov@gmail.com
//

namespace AForge
{
	using System;
	using System.Runtime.InteropServices;
	using System.Security;

	/// <summary>
	/// Windows API functions and structures
	/// </summary>
	/// 
	/// <remarks>Some Win32 API function's are used by the library to perform memory
	/// related routines.</remarks>
	/// 
	public class Win32
	{
		// Avoid class instantiation
		private Win32( ) { }

		/// <summary>
		/// Memory allocation attributes
		/// </summary>
		[Flags]
		public enum MemoryFlags
		{
			/// <summary>
			/// Allocates fixed memory
			/// </summary>
			Fixed		= 0,

			/// <summary>
			/// Initializes memory contents to zero
			/// </summary>
			ZeroInit	= 0x40
		}

		/// <summary>
		/// Allocate the specified number of bytes from the heap
		/// </summary>
		/// 
		/// <param name="flags">Memory allocation attributes (see <see cref="MemoryFlags"/>)</param>
		/// <param name="size">Number of bytes to allocate</param>
		/// 
		/// <returns>If the function succeeds, the return value is a handle to the newly allocated memory object.
		/// If the function fails, the return value is <b>IntPtr.Zero</b>.</returns>
		/// 
		[DllImport("kernel32.dll")]
		public static extern IntPtr LocalAlloc(
			[In, MarshalAs(UnmanagedType.I4)] MemoryFlags flags,
			int size );

		/// <summary>
		/// Free the specified local memory object and invalidate its handle
		/// </summary>
		/// 
		/// <param name="memBlock">Handle to the local memory object</param>
		/// 
		/// <returns>If the function succeeds, the return value is <b>IntPtr.Zero</b>.</returns>
		/// 
		[DllImport("kernel32.dll")]
		public static extern IntPtr LocalFree(
			IntPtr memBlock );

		/// <summary>
		/// Copy a block of memory
		/// </summary>
		/// 
		/// <param name="dst">Destination pointer</param>
		/// <param name="src">Source pointer</param>
		/// <param name="count">Memory block's length to copy</param>
		/// 
		/// <returns>Return's the value of <b>dst</b> - pointer to destination.</returns>
		/// 
		[DllImport("ntdll.dll")]
		public static extern IntPtr memcpy(
			IntPtr dst,
			IntPtr src,
			int count);

		/// <summary>
		/// Copy a block of memory
		/// </summary>
		/// 
		/// <param name="dst">Destination pointer</param>
		/// <param name="src">Source pointer</param>
		/// <param name="count">Memory block's length to copy</param>
		/// 
		/// <returns>Return's the value of <b>dst</b> - pointer to destination.</returns>
		/// 
		[DllImport("ntdll.dll")]
		public static extern unsafe byte * memcpy(
			byte * dst,
			byte * src,
			int count );

		/// <summary>
		/// Fills buffer with a specified value
		/// </summary>
		/// 
		/// <param name="dst">Destination pointer</param>
		/// <param name="filler">Value to use fo buffer filling</param>
		/// <param name="count">Size of buffer to fill</param>
		/// 
		/// <returns>Return's the value of <b>dst</b> - pointer to destination.</returns>
		/// 
		[DllImport("ntdll.dll")]
		public static extern IntPtr memset(
			IntPtr dst,
			int filler,
			int count );
	}
}