RuntimeEnvironment.cs

using System.Reflection;
using System.Runtime.CompilerServices;
using System.Security;
using System.Security.Permissions;
using System.Text;

namespace System.Runtime.InteropServices
{
    [ComVisible(true)]
    public class RuntimeEnvironment
    {
        public static string SystemConfigurationFile
        {
            [SecuritySafeCritical]
            get
            {
                StringBuilder stringBuilder = new StringBuilder(260);
                stringBuilder.Append(GetRuntimeDirectory());
                stringBuilder.Append(AppDomainSetup.RuntimeConfigurationFile);
                string text = stringBuilder.ToString();
                new FileIOPermission(FileIOPermissionAccess.PathDiscovery, text).Demand();
                return text;
            }
        }

        [Obsolete("Do not create instances of the RuntimeEnvironment class.  Call the static methods directly on this type instead", true)]
        public RuntimeEnvironment()
        {
        }

        [MethodImpl(MethodImplOptions.InternalCall)]
        [SecurityCritical]
        internal static extern string GetModuleFileName();

        [MethodImpl(MethodImplOptions.InternalCall)]
        [SecurityCritical]
        internal static extern string GetDeveloperPath();

        [MethodImpl(MethodImplOptions.InternalCall)]
        [SecurityCritical]
        internal static extern string GetHostBindingFile();

        [DllImport("QCall", CharSet = CharSet.Unicode)]
        [SecurityCritical]
        [SuppressUnmanagedCodeSecurity]
        internal static extern void _GetSystemVersion(StringHandleOnStack retVer);

        public static bool FromGlobalAccessCache(Assembly a)
        {
            return a.GlobalAssemblyCache;
        }

        [MethodImpl(MethodImplOptions.NoInlining)]
        [SecuritySafeCritical]
        public static string GetSystemVersion()
        {
            string s = null;
            _GetSystemVersion(JitHelpers.GetStringHandleOnStack(ref s));
            return s;
        }

        [SecuritySafeCritical]
        public static string GetRuntimeDirectory()
        {
            string runtimeDirectoryImpl = GetRuntimeDirectoryImpl();
            new FileIOPermission(FileIOPermissionAccess.PathDiscovery, runtimeDirectoryImpl).Demand();
            return runtimeDirectoryImpl;
        }

        [MethodImpl(MethodImplOptions.InternalCall)]
        [SecurityCritical]
        internal static extern string GetRuntimeDirectoryImpl();

        [DllImport("QCall", CharSet = CharSet.Unicode)]
        [SecurityCritical]
        [SuppressUnmanagedCodeSecurity]
        private static extern IntPtr GetRuntimeInterfaceImpl([In] [MarshalAs(UnmanagedType.LPStruct)] Guid clsid, [In] [MarshalAs(UnmanagedType.LPStruct)] Guid riid);

        [SecurityCritical]
        [ComVisible(false)]
        public static IntPtr GetRuntimeInterfaceAsIntPtr(Guid clsid, Guid riid)
        {
            return GetRuntimeInterfaceImpl(clsid, riid);
        }

        [SecurityCritical]
        [ComVisible(false)]
        public static object GetRuntimeInterfaceAsObject(Guid clsid, Guid riid)
        {
            IntPtr intPtr = IntPtr.Zero;
            try
            {
                intPtr = GetRuntimeInterfaceImpl(clsid, riid);
                return Marshal.GetObjectForIUnknown(intPtr);
            }
            finally
            {
                if (intPtr != IntPtr.Zero)
                {
                    Marshal.Release(intPtr);
                }
            }
        }
    }
}