Goals of this PR:
1. Allow passing in options to individual compressor
2. Do not change default behavior

Signed-off-by: Ramkumar Chinchani <rchincha@cisco.com>

Signed-off-by: Ramkumar Chinchani <rchincha@cisco.com>

Signed-off-by: Serge Hallyn <serge@hallyn.com>

…ix-empty-lgetxattr

2024 01 22/backport fix empty lgetxattr

generatelayer closes the tarwriter, but generateinsertlayer forgets to.

Closing the tarwriter writes the required footer of 1k of zeros.

This results in tar files that are complete but invalid, and different
reading tools will behave differently:

- bsdtar doesn't complain and exits 0
- gnu tar (and security scanning tools that use it) will exit 2 with an
unexpected EOF message
- python's tarfile library will raise an Unexpected EOF error
- golang's archive/tar library can raise an unexpected EOF error, but
  for some files created by generateinsertlayer, it just raises a
  plain EOF error, which means golang based tools generally ignore this
  and work fine, this includes umoci.

Signed-off-by: Michael McCracken <mikmccra@cisco.com>
(cherry picked from commit ad29ed3)

This warning is a little confusing when err is nil,
and doesn't add any info in that case. Let's clean that up.

Signed-off-by: Michael McCracken <mikmccra@cisco.com>
(cherry picked from commit 653952b)

add a check to image-verify to ensure that all generated tar blobs are
valid and do not cause gnu tar to exit nonzero

add an insert test that adds a very small file to trigger unexpected EOF
in the case where GenerateInsertLayer forgets to close the TarWriter.

Signed-off-by: Michael McCracken <mikmccra@cisco.com>
(cherry picked from commit 7bb2940)

…ckerfork-main/close-tarwriter

2024.02.22/stackerfork main/close tarwriter

add tarwriter fixes from upstream

Current behavior determines if a path is a whiteout if a overlay char
dev is present.

Additionally, also check the extended attrs.

Signed-off-by: Ramkumar Chinchani <rchincha@cisco.com>

fix: handle overlay xattr opaque bit

CI failures indicate that this could be another error code that needs
to be handled.

Signed-off-by: Ramkumar Chinchani <rchincha@cisco.com>