From 90cb01b2748550228d0bc179691a19ebb996fc36 Mon Sep 17 00:00:00 2001 From: Ophestra Date: Mon, 17 Feb 2025 19:00:43 +0900 Subject: system: move out of internal Signed-off-by: Ophestra --- system/link.go | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 system/link.go (limited to 'system/link.go') diff --git a/system/link.go b/system/link.go new file mode 100644 index 00000000..4182d560 --- /dev/null +++ b/system/link.go @@ -0,0 +1,47 @@ +package system + +import ( + "fmt" + "os" +) + +// Link registers an Op that links dst to src. +func (sys *I) Link(oldname, newname string) *I { return sys.LinkFileType(Process, oldname, newname) } + +// LinkFileType registers a file linking Op labelled with type et. +func (sys *I) LinkFileType(et Enablement, oldname, newname string) *I { + sys.lock.Lock() + defer sys.lock.Unlock() + + sys.ops = append(sys.ops, &Hardlink{et, newname, oldname}) + + return sys +} + +type Hardlink struct { + et Enablement + dst, src string +} + +func (l *Hardlink) Type() Enablement { return l.et } + +func (l *Hardlink) apply(sys *I) error { + sys.println("linking", l) + return sys.wrapErrSuffix(os.Link(l.src, l.dst), + fmt.Sprintf("cannot link %q:", l.dst)) +} + +func (l *Hardlink) revert(sys *I, ec *Criteria) error { + if ec.hasType(l) { + sys.printf("removing hard link %q", l.dst) + return sys.wrapErrSuffix(os.Remove(l.dst), + fmt.Sprintf("cannot remove hard link %q:", l.dst)) + } else { + sys.printf("skipping hard link %q", l.dst) + return nil + } +} + +func (l *Hardlink) Is(o Op) bool { l0, ok := o.(*Hardlink); return ok && l0 != nil && *l == *l0 } +func (l *Hardlink) Path() string { return l.src } +func (l *Hardlink) String() string { return fmt.Sprintf("%q from %q", l.dst, l.src) } -- cgit v1.3.1