WIP: Added packing of AR and TAR

2023-03-13 10:08:50 +01:00
parent e8a1378f60
commit 7cd5358ac8
18 changed files with 2071 additions and 4 deletions
--- a/AMWD.Common/Packing/Tar/Utils/UsTarHeader.cs
+++ b/AMWD.Common/Packing/Tar/Utils/UsTarHeader.cs
@@ -0,0 +1,136 @@
+using System;
+using System.Net;
+using System.Text;
+
+namespace AMWD.Common.Packing.Tar.Utils
+{
+	/// <summary>
+	/// UsTar header implementation.
+	/// </summary>
+	internal class UsTarHeader : TarHeader
+	{
+		private const string magic = "ustar";
+		private const string version = "  ";
+		private string groupName;
+
+		private string namePrefix = string.Empty;
+		private string userName;
+
+		public override string UserName
+		{
+			get
+			{
+				return userName.Replace("\0", string.Empty);
+			}
+			set
+			{
+				if (value.Length > 32)
+				{
+					throw new TarException("user name can not be longer than 32 chars");
+				}
+				userName = value;
+			}
+		}
+
+		public override string GroupName
+		{
+			get
+			{
+				return groupName.Replace("\0", string.Empty);
+			}
+			set
+			{
+				if (value.Length > 32)
+				{
+					throw new TarException("group name can not be longer than 32 chars");
+				}
+				groupName = value;
+			}
+		}
+
+		public override string FileName
+		{
+			get
+			{
+				return namePrefix.Replace("\0", string.Empty) + base.FileName.Replace("\0", string.Empty);
+			}
+			set
+			{
+				if (value.Length > 100)
+				{
+					if (value.Length > 255)
+					{
+						throw new TarException("UsTar fileName can not be longer thatn 255 chars");
+					}
+					int position = value.Length - 100;
+
+					// Find first path separator in the remaining 100 chars of the file name
+					while (!IsPathSeparator(value[position]))
+					{
+						++position;
+						if (position == value.Length)
+						{
+							break;
+						}
+					}
+					if (position == value.Length)
+						position = value.Length - 100;
+					namePrefix = value.Substring(0, position);
+					base.FileName = value.Substring(position, value.Length - position);
+				}
+				else
+				{
+					base.FileName = value;
+				}
+			}
+		}
+
+		public override bool UpdateHeaderFromBytes()
+		{
+			byte[] bytes = GetBytes();
+			UserName = Encoding.ASCII.GetString(bytes, 0x109, 32);
+			GroupName = Encoding.ASCII.GetString(bytes, 0x129, 32);
+			namePrefix = Encoding.ASCII.GetString(bytes, 347, 157);
+			return base.UpdateHeaderFromBytes();
+		}
+
+		internal static bool IsPathSeparator(char ch)
+		{
+			return (ch == '\\' || ch == '/' || ch == '|'); // All the path separators I ever met.
+		}
+
+		public override byte[] GetHeaderValue()
+		{
+			byte[] header = base.GetHeaderValue();
+
+			Encoding.ASCII.GetBytes(magic).CopyTo(header, 0x101); // Mark header as ustar
+			Encoding.ASCII.GetBytes(version).CopyTo(header, 0x106);
+			Encoding.ASCII.GetBytes(UserName).CopyTo(header, 0x109);
+			Encoding.ASCII.GetBytes(GroupName).CopyTo(header, 0x129);
+			Encoding.ASCII.GetBytes(namePrefix).CopyTo(header, 347);
+
+			if (SizeInBytes >= 0x1FFFFFFFF)
+			{
+				byte[] bytes = BitConverter.GetBytes(IPAddress.HostToNetworkOrder(SizeInBytes));
+				SetMarker(AlignTo12(bytes)).CopyTo(header, 124);
+			}
+
+			RecalculateChecksum(header);
+			Encoding.ASCII.GetBytes(HeaderChecksumString).CopyTo(header, 148);
+			return header;
+		}
+
+		private static byte[] SetMarker(byte[] bytes)
+		{
+			bytes[0] |= 0x80;
+			return bytes;
+		}
+
+		private static byte[] AlignTo12(byte[] bytes)
+		{
+			var retVal = new byte[12];
+			bytes.CopyTo(retVal, 12 - bytes.Length);
+			return retVal;
+		}
+	}
+}