/// <summary>Opens the specified file with the requested flags and mode.</summary>
        /// <param name="path">The path to the file.</param>
        /// <param name="flags">The flags with which to open the file.</param>
        /// <param name="mode">The mode for opening the file.</param>
        /// <returns>A SafeFileHandle for the opened file.</returns>
        internal static SafeFileHandle Open(string path, Interop.Sys.OpenFlags flags, int mode)
        {
            Debug.Assert(path != null);

            // If we fail to open the file due to a path not existing, we need to know whether to blame
            // the file itself or its directory.  If we're creating the file, then we blame the directory,
            // otherwise we blame the file.
            bool enoentDueToDirectory = (flags & Interop.Sys.OpenFlags.O_CREAT) != 0;

            // Open the file. 
            SafeFileHandle handle = Interop.CheckIo(
                Interop.Sys.Open(path, flags, mode),
                path, 
                isDirectory: enoentDueToDirectory,
                errorRewriter: e => (e.Error == Interop.Error.EISDIR) ? Interop.Error.EACCES.Info() : e);

            // Make sure it's not a directory; we do this after opening it once we have a file descriptor 
            // to avoid race conditions.
            Interop.Sys.FileStatus status;
            if (Interop.Sys.FStat(handle, out status) != 0)
            {
                handle.Dispose();
                throw Interop.GetExceptionForIoErrno(Interop.Sys.GetLastErrorInfo(), path);
            }
            if ((status.Mode & Interop.Sys.FileTypes.S_IFMT) == Interop.Sys.FileTypes.S_IFDIR)
            {
                handle.Dispose();
                throw Interop.GetExceptionForIoErrno(Interop.Error.EACCES.Info(), path, isDirectory: true);
            }

            return handle;
        }

        public TypeSymbol Parse(Interop.IMetadataImport mdImport, IntPtr signatureBytes, int signatureLength, out bool isIndexer) {
            _mdImport = mdImport;
            _signatureBytes = signatureBytes;
            _signatureLength = signatureLength;
            _signatureIndex = 0;

            isIndexer = false;

            byte signatureMarker = Read();
            byte typeMarker = (byte)(signatureMarker & 0xF);
            switch (typeMarker) {
                case Interop.SIG_FIELD:
                    return ParseField();
                case Interop.SIG_PROPERTY:
                    return ParseProperty(out isIndexer);
                case Interop.SIG_METHOD_DEFAULT:
                case Interop.SIG_METHOD_C:
                case Interop.SIG_METHOD_THISCALL:
                case Interop.SIG_METHOD_VARARG:
                case Interop.SIG_METHOD_STDCALL:
                case Interop.SIG_METHOD_FASTCALL:
                    bool isGeneric = ((signatureMarker & Interop.SIG_GENERIC) != 0);
                    return ParseMethod(isGeneric);
                default:
                    // TODO: Error
                    Debug.Fail("Unexpected signature type");
                    return null;
            }
        }

 protected unsafe void ProcessIpv6Address(Interop.Sys.IpAddressInfo* addressInfo, uint scopeId)
 {
     IPAddress address = IPAddressUtil.GetIPAddressFromNativeInfo(addressInfo);
     address.ScopeId = scopeId;
     AddAddress(address);
     _ipv6ScopeId = scopeId;
 }

 public ModuleDescriptionItem(Interop.Core.ModuleDescription @struct)
 {
     Name = @struct.Name;
     ShortName = @struct.ShortName;
     LongName = @struct.LongName;
     Description = @struct.Help;
 }

        private static FileStream CreateSharedBackingObject(
            Interop.libc.MemoryMappedProtections protections, long capacity,
            out string mapName, out SafeMemoryMappedFileHandle.FileStreamSource fileStreamSource)
        {
            // The POSIX shared memory object name must begin with '/'.  After that we just want something short and unique.
            mapName = "/" + MemoryMapObjectFilePrefix + Guid.NewGuid().ToString("N");
            fileStreamSource = SafeMemoryMappedFileHandle.FileStreamSource.ManufacturedSharedMemory;

            // Determine the flags to use when creating the shared memory object
            Interop.libc.OpenFlags flags = (protections & Interop.libc.MemoryMappedProtections.PROT_WRITE) != 0 ?
                Interop.libc.OpenFlags.O_RDWR :
                Interop.libc.OpenFlags.O_RDONLY;
            flags |= Interop.libc.OpenFlags.O_CREAT | Interop.libc.OpenFlags.O_EXCL; // CreateNew

            // Determine the permissions with which to create the file
            Interop.libc.Permissions perms = default(Interop.libc.Permissions);
            if ((protections & Interop.libc.MemoryMappedProtections.PROT_READ) != 0)
                perms |= Interop.libc.Permissions.S_IRUSR;
            if ((protections & Interop.libc.MemoryMappedProtections.PROT_WRITE) != 0)
                perms |= Interop.libc.Permissions.S_IWUSR;
            if ((protections & Interop.libc.MemoryMappedProtections.PROT_EXEC) != 0)
                perms |= Interop.libc.Permissions.S_IXUSR;

            // Create the shared memory object. Then enlarge it to the requested capacity.
            int fd;
            Interop.CheckIo(fd = Interop.libc.shm_open(mapName, flags, (int)perms), mapName);
            SafeFileHandle fileHandle = new SafeFileHandle((IntPtr)fd, ownsHandle: true);

            // Wrap the handle in a stream and return it.
            var fs = new FileStream(fileHandle, TranslateProtectionsToFileAccess(protections));
            fs.SetLength(capacity);
            return fs;
        }

        private static FileStream CreateSharedBackingObject(Interop.libc.MemoryMappedProtections protections, long capacity)
        {
            Directory.CreateDirectory(s_tempMapsDirectory);
            string path = Path.Combine(s_tempMapsDirectory, Guid.NewGuid().ToString("N"));
            
            FileAccess access =
                (protections & (Interop.libc.MemoryMappedProtections.PROT_READ | Interop.libc.MemoryMappedProtections.PROT_WRITE)) != 0 ? FileAccess.ReadWrite :
                (protections & (Interop.libc.MemoryMappedProtections.PROT_WRITE)) != 0 ? FileAccess.Write :
                FileAccess.Read;

            // Create the backing file, then immediately unlink it so that it'll be cleaned up when no longer in use.
            // Then enlarge it to the requested capacity.
            const int DefaultBufferSize = 0x1000;
            var fs = new FileStream(path, FileMode.CreateNew, TranslateProtectionsToFileAccess(protections), FileShare.ReadWrite, DefaultBufferSize);
            try
            {
                Interop.CheckIo(Interop.Sys.Unlink(path));
                fs.SetLength(capacity);
            }
            catch
            {
                fs.Dispose();
                throw;
            }
            return fs;
        }

 protected unsafe void ProcessIpv4Address(Interop.Sys.IpAddressInfo* addressInfo, Interop.Sys.IpAddressInfo* netMask)
 {
     IPAddress ipAddress = IPAddressUtil.GetIPAddressFromNativeInfo(addressInfo);
     IPAddress netMaskAddress = IPAddressUtil.GetIPAddressFromNativeInfo(netMask);
     AddAddress(ipAddress);
     _netMasks[ipAddress] = netMaskAddress;
 }

        // Translates the relevant icmpsendecho codes to a IPStatus code.
        private IPStatus GetIPStatus(Interop.IpHlpApi.IcmpV4Type type, Interop.IpHlpApi.IcmpV4Code code)
        {
            switch (type)
            {
                case Interop.IpHlpApi.IcmpV4Type.ICMP4_ECHO_REPLY:
                    return IPStatus.Success;
                case Interop.IpHlpApi.IcmpV4Type.ICMP4_SOURCE_QUENCH:
                    return IPStatus.SourceQuench;
                case Interop.IpHlpApi.IcmpV4Type.ICMP4_PARAM_PROB:
                    return IPStatus.ParameterProblem;
                case Interop.IpHlpApi.IcmpV4Type.ICMP4_TIME_EXCEEDED:
                    return IPStatus.TtlExpired;
                case Interop.IpHlpApi.IcmpV4Type.ICMP4_DST_UNREACH:
                    {
                        switch (code)
                        {
                            case Interop.IpHlpApi.IcmpV4Code.ICMP4_UNREACH_NET:
                                return IPStatus.DestinationNetworkUnreachable;
                            case Interop.IpHlpApi.IcmpV4Code.ICMP4_UNREACH_HOST:
                                return IPStatus.DestinationHostUnreachable;
                            case Interop.IpHlpApi.IcmpV4Code.ICMP4_UNREACH_PROTOCOL:
                                return IPStatus.DestinationProtocolUnreachable;
                            case Interop.IpHlpApi.IcmpV4Code.ICMP4_UNREACH_PORT:
                                return IPStatus.DestinationPortUnreachable;
                            case Interop.IpHlpApi.IcmpV4Code.ICMP4_UNREACH_FRAG_NEEDED:
                                return IPStatus.PacketTooBig;
                            default:
                                return IPStatus.DestinationUnreachable;
                        }
                    }
            }

            return IPStatus.Unknown;
        }

		public static ICorPublishProcess Wrap(Interop.CorPub.ICorPublishProcess objectToWrap)
		{
		    if (objectToWrap != null)
			{
				return new ICorPublishProcess(objectToWrap);
			}

		    return null;
		}

        /// <summary>Opens the specified file with the requested flags and mode.</summary>
        /// <param name="path">The path to the file.</param>
        /// <param name="flags">The flags with which to open the file.</param>
        /// <param name="mode">The mode for opening the file.</param>
        /// <returns>A SafeFileHandle for the opened file.</returns>
        internal static SafePipeHandle Open(string path, Interop.Sys.OpenFlags flags, int mode)
        {
            // Ideally this would be a constrained execution region, but we don't have access to PrepareConstrainedRegions.
            SafePipeHandle handle = Interop.CheckIo(Interop.Sys.OpenPipe(path, flags, mode));

            Debug.Assert(!handle.IsInvalid);

            return handle;
        }

 public bool TryRegister(int fileDescriptor, SocketAsyncEvents current, SocketAsyncEvents events, GCHandle handle, out Interop.Error error)
 {
     if (current == events)
     {
         error = Interop.Error.SUCCESS;
         return true;
     }
     return _backend.TryRegister(fileDescriptor, current, events, handle, out error);
 }

 /// <summary>
 /// Copies the address bytes out of the given native info's buffer and constructs a new IPAddress.
 /// </summary>
 /// <param name="addressInfo">A pointer to a native IpAddressInfo structure.</param>
 /// <returns>A new IPAddress created with the information in the native structure.</returns>
 public static unsafe IPAddress GetIPAddressFromNativeInfo(Interop.Sys.IpAddressInfo* addressInfo)
 {
     byte[] ipBytes = new byte[addressInfo->NumAddressBytes];
     fixed (byte* ipArrayPtr = ipBytes)
     {
         Buffer.MemoryCopy(addressInfo->AddressBytes, ipArrayPtr, ipBytes.Length, ipBytes.Length);
     }
     IPAddress ipAddress = new IPAddress(ipBytes);
     return ipAddress;
 }

 internal static extern int RegCreateKeyEx(
     SafeRegistryHandle hKey,
     String lpSubKey,
     int Reserved,
     String lpClass,
     int dwOptions,
     int samDesired,
     ref Interop.Kernel32.SECURITY_ATTRIBUTES secAttrs,
     out SafeRegistryHandle hkResult,
     out int lpdwDisposition);

        public static void Import(string filename, out string name, out Interop.Grid grid)
        {
            name = string.Empty;
            grid = null;

            MyObjectBuilder_Definitions loaded = null;
            if (File.Exists(filename))
            {
                using (FileStream stream = File.Open(filename, FileMode.Open))
                {
                    MyObjectBuilderSerializer.DeserializeXML<MyObjectBuilder_Definitions>(stream, out loaded);
                }
            }

            if (loaded != null)
            {
                foreach (MyObjectBuilder_ShipBlueprintDefinition blueprints in loaded.ShipBlueprints)
                {
                    name = blueprints.Id.SubtypeId;

                    grid = new Grid(loaded)
                    {
                        Name = name,
                        Path = filename,
                    };

                    foreach (MyObjectBuilder_CubeGrid cubegrid in blueprints.CubeGrids)
                    {
                        foreach (MyObjectBuilder_CubeBlock block in cubegrid.CubeBlocks)
                        {
                            if (block is MyObjectBuilder_TerminalBlock)
                            {
                                MyObjectBuilder_TerminalBlock terminalblock = (MyObjectBuilder_TerminalBlock)block;

                                long entityid = terminalblock.EntityId;
                                string type = GetBlockType(terminalblock.TypeId.ToString());

                                // TODO Use MyTexts.GetString(MyStringId id) to get default blocks names from MyTexts.resx (for localization)
                                string customname = String.IsNullOrEmpty(terminalblock.CustomName) ? type : terminalblock.CustomName;

                                if (block is MyObjectBuilder_MyProgrammableBlock)
                                {
                                    MyObjectBuilder_MyProgrammableBlock prog = (MyObjectBuilder_MyProgrammableBlock)block;
                                    grid.AddBlock(type, new TerminalBlock() { Name = customname, EntityID = entityid, IsProgram = true, Program = prog.Program });
                                }
                                else
                                {
                                    grid.AddBlock(type, new TerminalBlock() { Name = customname, EntityID = entityid, IsProgram = false });
                                }
                            }
                        }
                    }
                }
            }
        }

        private static bool GssInitSecurityContext(
            ref SafeGssContextHandle context,
            SafeGssCredHandle credential,
            bool isNtlm,
            SafeGssNameHandle targetName,
            Interop.NetSecurityNative.GssFlags inFlags,
            byte[] buffer,
            out byte[] outputBuffer,
            out uint outFlags,
            out int isNtlmUsed)
        {
            outputBuffer = null;
            outFlags = 0;

            // EstablishSecurityContext is called multiple times in a session.
            // In each call, we need to pass the context handle from the previous call.
            // For the first call, the context handle will be null.
            if (context == null)
            {
                context = new SafeGssContextHandle();
            }

            Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
            Interop.NetSecurityNative.Status status;

            try
            {
                Interop.NetSecurityNative.Status minorStatus;
                status = Interop.NetSecurityNative.InitSecContext(out minorStatus,
                                                          credential,
                                                          ref context,
                                                          isNtlm,
                                                          targetName,
                                                          (uint)inFlags,
                                                          buffer,
                                                          (buffer == null) ? 0 : buffer.Length,
                                                          ref token,
                                                          out outFlags,
                                                          out isNtlmUsed);

                if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) && (status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
                {
                    throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
                }

                outputBuffer = token.ToByteArray();
            }
            finally
            {
                token.Dispose();
            }

            return status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE;
        }

 public void AddBlock(string type, Interop.TerminalBlock block)
 {
     if (!String.IsNullOrEmpty(type))
     {
         if (!_Blocks.ContainsKey(type))
         {
             _Blocks.Add(type, new List<TerminalBlock>());
         }
         _Blocks[type].Add(block);
     }
 }

 [System.Security.SecurityCritical]  // auto-generated
 internal static SafeFileHandle UnsafeCreateFile(
     string lpFileName,
     int dwDesiredAccess,
     FileShare dwShareMode,
     ref Interop.mincore.SECURITY_ATTRIBUTES securityAttrs,
     FileMode dwCreationDisposition,
     int dwFlagsAndAttributes,
     IntPtr hTemplateFile)
 {
     return CreateFile(lpFileName, dwDesiredAccess, dwShareMode, ref securityAttrs, dwCreationDisposition, dwFlagsAndAttributes, hTemplateFile);
 }

        internal SystemIPv4InterfaceProperties(Interop.IpHlpApi.FIXED_INFO fixedInfo, Interop.IpHlpApi.IpAdapterAddresses ipAdapterAddresses)
        {
            _index = ipAdapterAddresses.index;
            _routingEnabled = fixedInfo.enableRouting;
            _dhcpEnabled = ((ipAdapterAddresses.flags & Interop.IpHlpApi.AdapterFlags.DhcpEnabled) != 0);
            _haveWins = (ipAdapterAddresses.firstWinsServerAddress != IntPtr.Zero);

            _mtu = ipAdapterAddresses.mtu;

            GetPerAdapterInfo(ipAdapterAddresses.index);
        }

        /// <summary>
        /// Get the HashAlgorithmName from the given ALG_ID
        /// </summary>
        internal static HashAlgorithmName? GetHashAlgorithmName(Interop.BCrypt.ECC_CURVE_ALG_ID_ENUM hashId)
        {
            CRYPT_OID_INFO oid = Interop.Crypt32.FindAlgIdOidInfo(hashId);
            if (oid.AlgId == -1)
            {
                // The original hash algorithm may not be found and is optional
                return null;
            }

            return new HashAlgorithmName(oid.Name);
        }

 internal static extern bool CreateProcessWithLogonW(
     string userName,
     string domain,
     IntPtr password,
     LogonFlags logonFlags,
     [MarshalAs(UnmanagedType.LPTStr)] string appName,
     StringBuilder cmdLine,
     int creationFlags,
     IntPtr environmentBlock,
     [MarshalAs(UnmanagedType.LPTStr)] string lpCurrentDirectory,
     Interop.Kernel32.STARTUPINFO lpStartupInfo,
     Interop.Kernel32.PROCESS_INFORMATION lpProcessInformation);