sharpcompress
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adamhathcock
tar extraction doesn't preserve file permissions
v0.18.2, netcoreapp2.0 on linux/mac,
tar contains
-rw-rw-r-- ... blaa.md
-rwxrwxrwx ... blaa.sh
result of extraction is
-rw-r--r-- ... blaa.md
-rw-r--r-- ... blaa.sh
(PreserveAttributes option to ExtractionOptions not implemented)
Applying file permissions is kind of out of scope. The file extraction methods are just convenience.
I don't mind extracting the files myself, but there is currently no way to get what the file permissions should be.
I think they should at least be exposed in the TarHeader so that implementors can choose to use mode/user/group if they choose.
https://github.com/adamhathcock/sharpcompress/blob/master/src/SharpCompress/Common/Tar/Headers/TarHeader.cs#L121
5 years later, there seems to be code for reading the permissions but is commented out, using PreserveAttributes throws NotImplementedException.
If setting permissions is out of the scope, can we please get a delegate for setting permissions, just like we have for creating symlinks?
Since UNIX permissions might not apply for Windows, alternatively just make the permission properties public and let the developers handle it in the ExtractAllEntries loop
No idea if that is the correct way to implement it. Can be tested with following code:
public static void Main()
{
using (Stream stream = File.OpenRead("Tar.tar"))
using (IReader reader = ReaderFactory.Open(stream))
{
int x = 0;
while (reader.MoveToNextEntry())
{
var en = reader.Entry as TarEntry;
Console.WriteLine($"{en.Key}\t" +
$"{PermissionString(en.Mode)}\t" +
$"{en.UserID}\t" +
$"{en.GroupId}");
}
}
}
public static string PermissionString(long perms)
{
const string ss = "drwxrwxrwx";
const string ns = "----------";
string s = "";
for(int i = 0; i < ss.Length; i++)
{
s += (perms & (1 << ss.Length - i - 1)) == 0 ? ns[i] : ss[i];
}
return s;
}