status-go/vendor/github.com/rjeczalik/notify/watcher_fen.go

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// Copyright (c) 2014-2015 The Notify Authors. All rights reserved.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
// +build solaris
package notify
import (
"fmt"
"os"
"syscall"
)
// newTrigger returns implementation of trigger.
func newTrigger(pthLkp map[string]*watched) trigger {
return &fen{
pthLkp: pthLkp,
cf: newCfen(),
}
}
// fen is a structure implementing trigger for FEN.
type fen struct {
// p is a FEN port identifier
p int
// pthLkp is a structure mapping monitored files/dir with data about them,
// shared with parent trg structure
pthLkp map[string]*watched
// cf wraps C operations for FEN
cf cfen
}
// watched is a data structure representing watched file/directory.
type watched struct {
trgWatched
}
// Stop implements trigger.
func (f *fen) Stop() error {
return f.cf.portAlert(f.p)
}
// Close implements trigger.
func (f *fen) Close() (err error) {
return syscall.Close(f.p)
}
// NewWatched implements trigger.
func (*fen) NewWatched(p string, fi os.FileInfo) (*watched, error) {
return &watched{trgWatched{p: p, fi: fi}}, nil
}
// Record implements trigger.
func (f *fen) Record(w *watched) {
f.pthLkp[w.p] = w
}
// Del implements trigger.
func (f *fen) Del(w *watched) {
delete(f.pthLkp, w.p)
}
func inter2pe(n interface{}) PortEvent {
pe, ok := n.(PortEvent)
if !ok {
panic(fmt.Sprintf("fen: type should be PortEvent, %T instead", n))
}
return pe
}
// Watched implements trigger.
func (f *fen) Watched(n interface{}) (*watched, int64, error) {
pe := inter2pe(n)
fo, ok := pe.PortevObject.(*FileObj)
if !ok || fo == nil {
panic(fmt.Sprintf("fen: type should be *FileObj, %T instead", fo))
}
w, ok := f.pthLkp[fo.Name]
if !ok {
return nil, 0, errNotWatched
}
return w, int64(pe.PortevEvents), nil
}
// init initializes FEN.
func (f *fen) Init() (err error) {
f.p, err = f.cf.portCreate()
return
}
func fi2fo(fi os.FileInfo, p string) FileObj {
st, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
panic(fmt.Sprintf("fen: type should be *syscall.Stat_t, %T instead", st))
}
return FileObj{Name: p, Atim: st.Atim, Mtim: st.Mtim, Ctim: st.Ctim}
}
// Unwatch implements trigger.
func (f *fen) Unwatch(w *watched) error {
return f.cf.portDissociate(f.p, FileObj{Name: w.p})
}
// Watch implements trigger.
func (f *fen) Watch(fi os.FileInfo, w *watched, e int64) error {
return f.cf.portAssociate(f.p, fi2fo(fi, w.p), int(e))
}
// Wait implements trigger.
func (f *fen) Wait() (interface{}, error) {
var (
pe PortEvent
err error
)
err = f.cf.portGet(f.p, &pe)
return pe, err
}
// IsStop implements trigger.
func (f *fen) IsStop(n interface{}, err error) bool {
return err == syscall.EBADF || inter2pe(n).PortevSource == srcAlert
}
func init() {
encode = func(e Event, dir bool) (o int64) {
// Create event is not supported by FEN. Instead FileModified event will
// be registered. If this event will be reported on dir which is to be
// monitored for Create, dir will be rescanned and Create events will
// be generated and returned for new files. In case of files,
// if not requested FileModified event is reported, it will be ignored.
o = int64(e &^ Create)
if (e&Create != 0 && dir) || e&Write != 0 {
o = (o &^ int64(Write)) | int64(FileModified)
}
// Following events are 'exception events' and as such cannot be requested
// explicitly for monitoring or filtered out. If the will be reported
// by FEN and not subscribed with by user, they will be filtered out by
// watcher's logic.
o &= int64(^Rename & ^Remove &^ FileDelete &^ FileRenameTo &^
FileRenameFrom &^ Unmounted &^ MountedOver)
return
}
nat2not = map[Event]Event{
FileModified: Write,
FileRenameFrom: Rename,
FileDelete: Remove,
FileAccess: Event(0),
FileAttrib: Event(0),
FileRenameTo: Event(0),
FileTrunc: Event(0),
FileNoFollow: Event(0),
Unmounted: Event(0),
MountedOver: Event(0),
}
not2nat = map[Event]Event{
Write: FileModified,
Rename: FileRenameFrom,
Remove: FileDelete,
}
}