System.Net.NameResolutionPal.NativeToHostEntry C# (CSharp) Method

        private static IPHostEntry NativeToHostEntry(IntPtr nativePointer)
        {
            //
            // marshal pointer to struct
            //

            hostent Host = Marshal.PtrToStructure<hostent>(nativePointer);
            IPHostEntry HostEntry = new IPHostEntry();

            if (Host.h_name != IntPtr.Zero)
            {
                HostEntry.HostName = Marshal.PtrToStringAnsi(Host.h_name);
                if (NetEventSource.IsEnabled) NetEventSource.Info(null, $"HostEntry.HostName: {HostEntry.HostName}");
            }

            // decode h_addr_list to ArrayList of IP addresses.
            // The h_addr_list field is really a pointer to an array of pointers
            // to IP addresses. Loop through the array, and while the pointer
            // isn't NULL read the IP address, convert it to an IPAddress class,
            // and add it to the list.

            var TempIPAddressList = new List<IPAddress>();
            int IPAddressToAdd;
            string AliasToAdd;
            IntPtr currentArrayElement;

            //
            // get the first pointer in the array
            //
            currentArrayElement = Host.h_addr_list;
            nativePointer = Marshal.ReadIntPtr(currentArrayElement);

            while (nativePointer != IntPtr.Zero)
            {
                //
                // if it's not null it points to an IPAddress,
                // read it...
                //
                IPAddressToAdd = Marshal.ReadInt32(nativePointer);
#if BIGENDIAN
                // IP addresses from native code are always a byte array
                // converted to int.  We need to convert the address into
                // a uniform integer value.
                IPAddressToAdd = (int)(((uint)IPAddressToAdd << 24) |
                                        (((uint)IPAddressToAdd & 0x0000FF00) << 8) |
                                        (((uint)IPAddressToAdd >> 8) & 0x0000FF00) |
                                        ((uint)IPAddressToAdd >> 24));
#endif

                if (NetEventSource.IsEnabled) NetEventSource.Info(null, $"currentArrayElement:{currentArrayElement} nativePointer:{nativePointer} IPAddressToAdd:{IPAddressToAdd}");

                //
                // ...and add it to the list
                //
                TempIPAddressList.Add(new IPAddress((long)IPAddressToAdd & 0x0FFFFFFFF));

                //
                // now get the next pointer in the array and start over
                //
                currentArrayElement = IntPtrHelper.Add(currentArrayElement, IntPtr.Size);
                nativePointer = Marshal.ReadIntPtr(currentArrayElement);
            }

            HostEntry.AddressList = TempIPAddressList.ToArray();

            //
            // Now do the same thing for the aliases.
            //

            var TempAliasList = new List<string>();

            currentArrayElement = Host.h_aliases;
            nativePointer = Marshal.ReadIntPtr(currentArrayElement);

            while (nativePointer != IntPtr.Zero)
            {
                if (NetEventSource.IsEnabled) NetEventSource.Info(null, $"currentArrayElement:{currentArrayElement} nativePointer:{nativePointer}");

                //
                // if it's not null it points to an Alias,
                // read it...
                //
                AliasToAdd = Marshal.PtrToStringAnsi(nativePointer);

                //
                // ...and add it to the list
                //
                TempAliasList.Add(AliasToAdd);

                //
                // now get the next pointer in the array and start over
                //
                currentArrayElement = IntPtrHelper.Add(currentArrayElement, IntPtr.Size);
                nativePointer = Marshal.ReadIntPtr(currentArrayElement);
            }

            HostEntry.Aliases = TempAliasList.ToArray();

            return HostEntry;
        } // NativeToHostEntry