sync: refactor file opening into OpenFileNoFollow()

Make it public because it will be used by other packages in the next
commit.

diff --git a/cmd/safcm-remote/sync/files.go b/cmd/safcm-remote/sync/files.go
index 06bc4066643b1394b286363e2bd7665a136ed722..12508ce08c2f7e7d2c17b74dca980285ec01f334 100644 (file)
--- a/cmd/safcm-remote/sync/files.go
+++ b/cmd/safcm-remote/sync/files.go
@@ -110,10 +110,7 @@ func (s *Sync) syncFile(file *safcm.File, changed *bool) error {
 
        var oldStat fs.FileInfo
 reopen:
-       oldFh, err := os.OpenFile(file.Path,
-               // O_NOFOLLOW prevents symlink attacks
-               // O_NONBLOCK is necessary to prevent blocking on FIFOs
-               os.O_RDONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0)
+       oldFh, err := OpenFileNoFollow(file.Path)
        if err != nil {
                err := err.(*fs.PathError)
                if err.Err == syscall.ELOOP {
@@ -273,8 +270,7 @@ reopen:
                // a symlink at this point. There's no lchmod so open the
                // directory.
                debugf("chmodding %s", file.Mode)
-               dh, err := os.OpenFile(file.Path,
-                       os.O_RDONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0)
+               dh, err := OpenFileNoFollow(file.Path)
                if err != nil {
                        return err
                }
@@ -502,6 +498,13 @@ func diffData(oldData []byte, newData []byte) (string, error) {
        return result, nil
 }
 
+func OpenFileNoFollow(path string) (*os.File, error) {
+       return os.OpenFile(path,
+               // O_NOFOLLOW prevents symlink attacks
+               // O_NONBLOCK is necessary to prevent blocking on FIFOs
+               os.O_RDONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0)
+}
+
 // syncPath syncs path, which should be a directory. To guarantee durability
 // it must be called on a parent directory after adding, renaming or removing
 // files therein.