The core issue comes about when you consider a trivial example of a path
like "./README". This path is lexically equivalent within mtree to
"README", but a simple string comparison will yield the wrong result.
Instead you need to lexically clean the path first (filepath.Clean isn't
enough here -- you need to prepend a "/" and then do filepath.Clean).
In gomtree we generate spec files in the same style of FreeBSD's
mtree(8), so you would be very hard-pressed to find an example of such
an inconsistency. However casync's mtree implementation does not
generate leading "./" for root paths which results in "missing" entries.
The implementation of CleanPath was written by me for umoci originally,
then later I copied it to runc for other uses, and now I've copied it
here. Since I'm the sole author I'm effectively dual-licensing it under
this project's license to avoid having to relicense go-mtree for no good
reason (or deal with the multiple-license hassle).
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This allows people to create synthetic InodeDeltas, which is something
that umoci would like to be able to do in order to nicely create 'umoci
insert' layers.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
During the rework of how xattr fields are handled, the comparison code
was not correctly updated. As a result, changes to xattrs would not be
detected in any form. This was detected in the umoci integration suite.
In addition, fix the dh.UsedKeywords logic so auto-detection works
correctly with prefix-based xattrs.
Fixes: ed464af779 ("*: xattr can Update()")
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This is a gnarly patchset that has been mashed together.
It uncovered that some aspects of Check were never really working
correctly for `xattr` keywords, but also the `Update()` had been left
undone for a while.
This includes some API changes around the `Keyword` and `KeyVal` types.
Also I would like to update the signature for the `UpdateKeywordFunc` to
just accept a `KeyVal` as an argugment, rather than a keyword AND the
value. with this context there would be no need to guess on the value of
what's passed to the xattr update function of whether it needs or
already is base64 encoded.
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
KeyVal specific functions can be a part of the struct.
Also add tests and fix the NewValue functions for suffixes
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
This allows for restoring some attributes of files from the state in an
mtree Manifest
Reported-by: Matthew Garrett <Matthewgarrett@google.com>
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
Because of how xattr works (it will not be set on all files, but it's
possible for it to be added to a file without changing any other key)
it's necessary that we _always_ compute a diff when we hit an inode that
has xattr keys set.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Adding another test validated from the FreeBSD workflow.
Just because the keywords requested to be validated are not present in
the manifest, it is not an error.
Also, if the keywords from a new manifest are not present in a prior
manifest, then only compare the common keywords.
Fixes https://github.com/vbatts/go-mtree/issues/86
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
This is part of a patchset that refactors all of the checking logic into
comparison operations. Essentially, provide a Compare(...) function that
allows for two different manifests to be compared. Extra and missing
entries are supported in addition to the standard modified entry, and by
implementing as a manifest comparison there is no double-scanning of the
manifest source.
The main annoyance is that we have to also include tar_time handling,
which has not been abstracted inside keywords.go. This is a bit ugly
right now, but works fine for the moment.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
