go-mtree/check.go
Aleksa Sarai e22043cb86
walk: implement FsEval hooks
In certain circumstances (such as the manifest generation of a
filesystem as an unprivileged user) it is important to provide hooks
that override the default os.* implementation of filesystem-related
functions.

In order to avoid merging too much code from outside projects (such as
umoci) this is implemented by providing FsEval hooks to Walk() and
Check(). This allows for users of go-mtree to modify how filesystem
checks are done, without compromising the simplicity of go-mtree's code.

Signed-off-by: Aleksa Sarai <asarai@suse.de>
2016-12-14 16:26:31 +11:00

30 lines
1 KiB
Go

package mtree
// Check a root directory path against the DirectoryHierarchy, regarding only
// the available keywords from the list and each entry in the hierarchy.
// If keywords is nil, the check all present in the DirectoryHierarchy
//
// This is equivalent to creating a new DirectoryHierarchy with Walk(root, nil,
// keywords, fs) and then doing a Compare(dh, newDh, keywords).
func Check(root string, dh *DirectoryHierarchy, keywords []Keyword, fs FsEval) ([]InodeDelta, error) {
if keywords == nil {
keywords = dh.UsedKeywords()
}
newDh, err := Walk(root, nil, keywords, fs)
if err != nil {
return nil, err
}
return Compare(dh, newDh, keywords)
}
// TarCheck is the tar equivalent of checking a file hierarchy spec against a
// tar stream to determine if files have been changed. This is precisely
// equivalent to Compare(dh, tarDH, keywords).
func TarCheck(tarDH, dh *DirectoryHierarchy, keywords []Keyword) ([]InodeDelta, error) {
if keywords == nil {
return Compare(dh, tarDH, dh.UsedKeywords())
}
return Compare(dh, tarDH, keywords)
}