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

144 lines
4.5 KiB
Go

// 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.
package notify
import (
"fmt"
"strings"
)
// Event represents the type of filesystem action.
//
// Number of available event values is dependent on the target system or the
// watcher implmenetation used (e.g. it's possible to use either kqueue or
// FSEvents on Darwin).
//
// Please consult documentation for your target platform to see list of all
// available events.
type Event uint32
// Create, Remove, Write and Rename are the only event values guaranteed to be
// present on all platforms.
const (
Create = osSpecificCreate
Remove = osSpecificRemove
Write = osSpecificWrite
Rename = osSpecificRename
// All is handful alias for all platform-independent event values.
All = Create | Remove | Write | Rename
)
const internal = recursive | omit
// String implements fmt.Stringer interface.
func (e Event) String() string {
var s []string
for _, strmap := range []map[Event]string{estr, osestr} {
for ev, str := range strmap {
if e&ev == ev {
s = append(s, str)
}
}
}
return strings.Join(s, "|")
}
// EventInfo describes an event reported by the underlying filesystem notification
// subsystem.
//
// It always describes single event, even if the OS reported a coalesced action.
// Reported path is absolute and clean.
//
// For non-recursive watchpoints its base is always equal to the path passed
// to corresponding Watch call.
//
// The value of Sys if system-dependent and can be nil.
//
// # Sys
//
// Under Darwin (FSEvents) Sys() always returns a non-nil *notify.FSEvent value,
// which is defined as:
//
// type FSEvent struct {
// Path string // real path of the file or directory
// ID uint64 // ID of the event (FSEventStreamEventId)
// Flags uint32 // joint FSEvents* flags (FSEventStreamEventFlags)
// }
//
// For possible values of Flags see Darwin godoc for notify or FSEvents
// documentation for FSEventStreamEventFlags constants:
//
// https://developer.apple.com/library/mac/documentation/Darwin/Reference/FSEvents_Ref/index.html#//apple_ref/doc/constant_group/FSEventStreamEventFlags
//
// Under Linux (inotify) Sys() always returns a non-nil *unix.InotifyEvent
// value, defined as:
//
// type InotifyEvent struct {
// Wd int32 // Watch descriptor
// Mask uint32 // Mask describing event
// Cookie uint32 // Unique cookie associating related events (for rename(2))
// Len uint32 // Size of name field
// Name [0]uint8 // Optional null-terminated name
// }
//
// More information about inotify masks and the usage of inotify_event structure
// can be found at:
//
// http://man7.org/linux/man-pages/man7/inotify.7.html
//
// Under Darwin, DragonFlyBSD, FreeBSD, NetBSD, OpenBSD (kqueue) Sys() always
// returns a non-nil *notify.Kevent value, which is defined as:
//
// type Kevent struct {
// Kevent *syscall.Kevent_t // Kevent is a kqueue specific structure
// FI os.FileInfo // FI describes file/dir
// }
//
// More information about syscall.Kevent_t can be found at:
//
// https://www.freebsd.org/cgi/man.cgi?query=kqueue
//
// Under Windows (ReadDirectoryChangesW) Sys() always returns nil. The documentation
// of watcher's WinAPI function can be found at:
//
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa365465%28v=vs.85%29.aspx
type EventInfo interface {
Event() Event // event value for the filesystem action
Path() string // real path of the file or directory
Sys() interface{} // underlying data source (can return nil)
}
type isDirer interface {
isDir() (bool, error)
}
var _ fmt.Stringer = (*event)(nil)
var _ isDirer = (*event)(nil)
// String implements fmt.Stringer interface.
func (e *event) String() string {
return e.Event().String() + `: "` + e.Path() + `"`
}
var estr = map[Event]string{
Create: "notify.Create",
Remove: "notify.Remove",
Write: "notify.Write",
Rename: "notify.Rename",
// Display name for recursive event is added only for debugging
// purposes. It's an internal event after all and won't be exposed to the
// user. Having Recursive event printable is helpful, e.g. for reading
// testing failure messages:
//
// --- FAIL: TestWatchpoint (0.00 seconds)
// watchpoint_test.go:64: want diff=[notify.Remove notify.Create|notify.Remove];
// got [notify.Remove notify.Remove|notify.Create] (i=1)
//
// Yup, here the diff have Recursive event inside. Go figure.
recursive: "recursive",
omit: "omit",
}