[ARC] Added structures.

Aaru.Archives/Aaru.Archives.csproj.DotSettings

@@ -2,6 +2,7 @@
                         xmlns:s="clr-namespace:System;assembly=mscorlib"
                         xmlns:wpf="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                         xml:space="preserve">
-	<s:Boolean x:Key="/Default/CodeInspection/NamespaceProvider/NamespaceFoldersToSkip/=localization/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/CodeInspection/NamespaceProvider/NamespaceFoldersToSkip/=arc/@EntryIndexedValue">True</s:Boolean>
+  <s:Boolean x:Key="/Default/CodeInspection/NamespaceProvider/NamespaceFoldersToSkip/=localization/@EntryIndexedValue">True</s:Boolean>
   <s:Boolean x:Key="/Default/CodeInspection/NamespaceProvider/NamespaceFoldersToSkip/=symbian/@EntryIndexedValue">True</s:Boolean>
   <s:Boolean x:Key="/Default/CodeInspection/NamespaceProvider/NamespaceFoldersToSkip/=zoo/@EntryIndexedValue">True</s:Boolean></wpf:ResourceDictionary>

Aaru.Archives/Arc/Consts.cs

@@ -0,0 +1,7 @@
+namespace Aaru.Archives;
+
+public partial class Arc
+{
+    const byte MARKER = 0x1A;
+    const byte FNLEN  = 13;
+}

Aaru.Archives/Arc/Enums.cs

@@ -0,0 +1,52 @@
+namespace Aaru.Archives;
+
+public partial class Arc
+{
+#region ArchiveInformationType enum
+
+    public enum ArchiveInformationType : byte
+    {
+        Description = 0,
+        Creator     = 1,
+        Modifier    = 2
+    }
+
+#endregion
+
+#region FileInformationType enum
+
+    public enum FileInformationType : byte
+    {
+        Description   = 0,
+        LongName      = 1,
+        ExtendedDates = 2,
+        Icon          = 3,
+        Attributes    = 4
+    }
+
+#endregion
+
+#region Method enum
+
+    public enum Method : byte
+    {
+        EndOfArchive       = 0,
+        UnpackedOld        = 1,
+        Unpacked           = 2,
+        Pack               = 3,
+        Squeeze            = 4,
+        CrunchOld          = 5,
+        Crunch             = 6,
+        CrunchFastHash     = 7,
+        CrunchDynamic      = 8,
+        Squash             = 9,
+        Crush              = 10,
+        Distill            = 11,
+        ArchiveInformation = 20,
+        FileInformation    = 21,
+        Subdirectory       = 30,
+        SubdirectoryEnd    = 31
+    }
+
+#endregion
+}

Aaru.Archives/Arc/Structs.cs

@@ -0,0 +1,24 @@
+using System.Runtime.InteropServices;
+
+namespace Aaru.Archives;
+
+public partial class Arc
+{
+#region Nested type: Header
+
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
+    readonly struct Header
+    {
+        public readonly byte marker;
+        public readonly byte method;
+        [MarshalAs(UnmanagedType.ByValArray, SizeConst = FNLEN)]
+        public readonly byte[] filename;
+        public readonly int    compressed;
+        public readonly ushort date;
+        public readonly ushort time;
+        public readonly ushort crc;
+        public readonly int    uncompressed;
+    }
+
+#endregion
+}