mirror-processhacker/1.x/trunk/ProcessHacker/SharpDevelop/Wrappers/Util.cs

// <file>
//     <copyright see="prj:///doc/copyright.txt"/>
//     <license see="prj:///doc/license.txt"/>
//     <owner name="David Srbecký" email="dsrbecky@gmail.com"/>
//     <version>$Revision: 2284 $</version>
// </file>

#pragma warning disable 1591

using System;
using System.Runtime.InteropServices;
using ProcessHacker.Native;

namespace Debugger.Wrappers
{
	public delegate void UnmanagedStringGetter(uint pStringLenght, out uint stringLenght, IntPtr pString);
	
	public static class Util
	{
		public static string GetString(UnmanagedStringGetter getter)
		{
			return GetString(getter, 64, true);
		}
		
		public static string GetString(UnmanagedStringGetter getter, uint defaultLenght, bool trim)
		{
		    uint exactLenght;
			
			// First attempt
            IntPtr unmanagedString = MemoryAlloc.PrivateHeap.Allocate((int)defaultLenght * 2 + 2);
			getter(defaultLenght, out exactLenght, defaultLenght > 0 ? unmanagedString : IntPtr.Zero);
			
			if(exactLenght > defaultLenght) 
            {
				// Second attempt
                MemoryAlloc.PrivateHeap.Free(unmanagedString);
                unmanagedString = MemoryAlloc.PrivateHeap.Allocate((int)exactLenght * 2 + 2); // + 2 for terminating zero
				getter(exactLenght, out exactLenght, unmanagedString);
			}
			
			// Return managed string and free unmanaged memory
			string managedString = Marshal.PtrToStringUni(unmanagedString, (int)exactLenght);
			//Console.WriteLine("Marshaled string from COM: \"" + managedString + "\" lenght=" + managedString.Length + " arrayLenght=" + exactLenght);
			// The API might or might not include terminating null at the end
			if (trim) 
            {
				managedString = managedString.TrimEnd('\0');
			}

            MemoryAlloc.PrivateHeap.Free(unmanagedString);
			return managedString;
		}
	}
}

#pragma warning restore 1591