containerd/archive/link_default.go
Samuel Karp 2ab8c12fc8
archive: use Linkat on FreeBSD for hardlinks
Calling link(2) with a symlink as the target will cause FreeBSD to
attempt to create a new hard link pointing to the target of the symlink
rather than a hardlink to the symlink itself. By contrast, Linux creates
a hardlink to the symlink.

Use linkat(2) instead, which accepts a flag controlling this behavior.
If linkat(2) is called with AT_SYMLINK_FOLLOW, it will behave the same
as link(2).  If linkat(2) is called without AT_SYMLINK_FOLLOW, it will
behave the same as Linux's link(2) instead.

See FreeBSD's implementation of ln(1), which uses linkat(2) and controls
this behavior by way of the -P and -L flags:
3003117253/bin/ln/ln.c (L342-L343)

Signed-off-by: Samuel Karp <me@samuelkarp.com>
2022-06-09 18:54:09 -07:00

26 lines
726 B
Go

//go:build !freebsd
/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package archive
import "os"
func link(oldname, newname string) error {
return os.Link(oldname, newname)
}