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Kirill Smelkov
wendelin.core
Commits
71b70602
Commit
71b70602
authored
Oct 25, 2020
by
Kirill Smelkov
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de1db2fe
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+0
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wcfs/vendor/github.com/fsnotify/fsnotify/windows.go
wcfs/vendor/github.com/fsnotify/fsnotify/windows.go
+0
-561
wcfs/vendor/lab.nexedi.com/kirr/go123/xcontainer/list/list.go
.../vendor/lab.nexedi.com/kirr/go123/xcontainer/list/list.go
+0
-66
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wcfs/vendor/github.com/fsnotify/fsnotify/windows.go
deleted
100644 → 0
View file @
de1db2fe
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
package
fsnotify
import
(
"errors"
"fmt"
"os"
"path/filepath"
"runtime"
"sync"
"syscall"
"unsafe"
)
// Watcher watches a set of files, delivering events to a channel.
type
Watcher
struct
{
Events
chan
Event
Errors
chan
error
isClosed
bool
// Set to true when Close() is first called
mu
sync
.
Mutex
// Map access
port
syscall
.
Handle
// Handle to completion port
watches
watchMap
// Map of watches (key: i-number)
input
chan
*
input
// Inputs to the reader are sent on this channel
quit
chan
chan
<-
error
}
// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
func
NewWatcher
()
(
*
Watcher
,
error
)
{
port
,
e
:=
syscall
.
CreateIoCompletionPort
(
syscall
.
InvalidHandle
,
0
,
0
,
0
)
if
e
!=
nil
{
return
nil
,
os
.
NewSyscallError
(
"CreateIoCompletionPort"
,
e
)
}
w
:=
&
Watcher
{
port
:
port
,
watches
:
make
(
watchMap
),
input
:
make
(
chan
*
input
,
1
),
Events
:
make
(
chan
Event
,
50
),
Errors
:
make
(
chan
error
),
quit
:
make
(
chan
chan
<-
error
,
1
),
}
go
w
.
readEvents
()
return
w
,
nil
}
// Close removes all watches and closes the events channel.
func
(
w
*
Watcher
)
Close
()
error
{
if
w
.
isClosed
{
return
nil
}
w
.
isClosed
=
true
// Send "quit" message to the reader goroutine
ch
:=
make
(
chan
error
)
w
.
quit
<-
ch
if
err
:=
w
.
wakeupReader
();
err
!=
nil
{
return
err
}
return
<-
ch
}
// Add starts watching the named file or directory (non-recursively).
func
(
w
*
Watcher
)
Add
(
name
string
)
error
{
if
w
.
isClosed
{
return
errors
.
New
(
"watcher already closed"
)
}
in
:=
&
input
{
op
:
opAddWatch
,
path
:
filepath
.
Clean
(
name
),
flags
:
sysFSALLEVENTS
,
reply
:
make
(
chan
error
),
}
w
.
input
<-
in
if
err
:=
w
.
wakeupReader
();
err
!=
nil
{
return
err
}
return
<-
in
.
reply
}
// Remove stops watching the the named file or directory (non-recursively).
func
(
w
*
Watcher
)
Remove
(
name
string
)
error
{
in
:=
&
input
{
op
:
opRemoveWatch
,
path
:
filepath
.
Clean
(
name
),
reply
:
make
(
chan
error
),
}
w
.
input
<-
in
if
err
:=
w
.
wakeupReader
();
err
!=
nil
{
return
err
}
return
<-
in
.
reply
}
const
(
// Options for AddWatch
sysFSONESHOT
=
0x80000000
sysFSONLYDIR
=
0x1000000
// Events
sysFSACCESS
=
0x1
sysFSALLEVENTS
=
0xfff
sysFSATTRIB
=
0x4
sysFSCLOSE
=
0x18
sysFSCREATE
=
0x100
sysFSDELETE
=
0x200
sysFSDELETESELF
=
0x400
sysFSMODIFY
=
0x2
sysFSMOVE
=
0xc0
sysFSMOVEDFROM
=
0x40
sysFSMOVEDTO
=
0x80
sysFSMOVESELF
=
0x800
// Special events
sysFSIGNORED
=
0x8000
sysFSQOVERFLOW
=
0x4000
)
func
newEvent
(
name
string
,
mask
uint32
)
Event
{
e
:=
Event
{
Name
:
name
}
if
mask
&
sysFSCREATE
==
sysFSCREATE
||
mask
&
sysFSMOVEDTO
==
sysFSMOVEDTO
{
e
.
Op
|=
Create
}
if
mask
&
sysFSDELETE
==
sysFSDELETE
||
mask
&
sysFSDELETESELF
==
sysFSDELETESELF
{
e
.
Op
|=
Remove
}
if
mask
&
sysFSMODIFY
==
sysFSMODIFY
{
e
.
Op
|=
Write
}
if
mask
&
sysFSMOVE
==
sysFSMOVE
||
mask
&
sysFSMOVESELF
==
sysFSMOVESELF
||
mask
&
sysFSMOVEDFROM
==
sysFSMOVEDFROM
{
e
.
Op
|=
Rename
}
if
mask
&
sysFSATTRIB
==
sysFSATTRIB
{
e
.
Op
|=
Chmod
}
return
e
}
const
(
opAddWatch
=
iota
opRemoveWatch
)
const
(
provisional
uint64
=
1
<<
(
32
+
iota
)
)
type
input
struct
{
op
int
path
string
flags
uint32
reply
chan
error
}
type
inode
struct
{
handle
syscall
.
Handle
volume
uint32
index
uint64
}
type
watch
struct
{
ov
syscall
.
Overlapped
ino
*
inode
// i-number
path
string
// Directory path
mask
uint64
// Directory itself is being watched with these notify flags
names
map
[
string
]
uint64
// Map of names being watched and their notify flags
rename
string
// Remembers the old name while renaming a file
buf
[
4096
]
byte
}
type
indexMap
map
[
uint64
]
*
watch
type
watchMap
map
[
uint32
]
indexMap
func
(
w
*
Watcher
)
wakeupReader
()
error
{
e
:=
syscall
.
PostQueuedCompletionStatus
(
w
.
port
,
0
,
0
,
nil
)
if
e
!=
nil
{
return
os
.
NewSyscallError
(
"PostQueuedCompletionStatus"
,
e
)
}
return
nil
}
func
getDir
(
pathname
string
)
(
dir
string
,
err
error
)
{
attr
,
e
:=
syscall
.
GetFileAttributes
(
syscall
.
StringToUTF16Ptr
(
pathname
))
if
e
!=
nil
{
return
""
,
os
.
NewSyscallError
(
"GetFileAttributes"
,
e
)
}
if
attr
&
syscall
.
FILE_ATTRIBUTE_DIRECTORY
!=
0
{
dir
=
pathname
}
else
{
dir
,
_
=
filepath
.
Split
(
pathname
)
dir
=
filepath
.
Clean
(
dir
)
}
return
}
func
getIno
(
path
string
)
(
ino
*
inode
,
err
error
)
{
h
,
e
:=
syscall
.
CreateFile
(
syscall
.
StringToUTF16Ptr
(
path
),
syscall
.
FILE_LIST_DIRECTORY
,
syscall
.
FILE_SHARE_READ
|
syscall
.
FILE_SHARE_WRITE
|
syscall
.
FILE_SHARE_DELETE
,
nil
,
syscall
.
OPEN_EXISTING
,
syscall
.
FILE_FLAG_BACKUP_SEMANTICS
|
syscall
.
FILE_FLAG_OVERLAPPED
,
0
)
if
e
!=
nil
{
return
nil
,
os
.
NewSyscallError
(
"CreateFile"
,
e
)
}
var
fi
syscall
.
ByHandleFileInformation
if
e
=
syscall
.
GetFileInformationByHandle
(
h
,
&
fi
);
e
!=
nil
{
syscall
.
CloseHandle
(
h
)
return
nil
,
os
.
NewSyscallError
(
"GetFileInformationByHandle"
,
e
)
}
ino
=
&
inode
{
handle
:
h
,
volume
:
fi
.
VolumeSerialNumber
,
index
:
uint64
(
fi
.
FileIndexHigh
)
<<
32
|
uint64
(
fi
.
FileIndexLow
),
}
return
ino
,
nil
}
// Must run within the I/O thread.
func
(
m
watchMap
)
get
(
ino
*
inode
)
*
watch
{
if
i
:=
m
[
ino
.
volume
];
i
!=
nil
{
return
i
[
ino
.
index
]
}
return
nil
}
// Must run within the I/O thread.
func
(
m
watchMap
)
set
(
ino
*
inode
,
watch
*
watch
)
{
i
:=
m
[
ino
.
volume
]
if
i
==
nil
{
i
=
make
(
indexMap
)
m
[
ino
.
volume
]
=
i
}
i
[
ino
.
index
]
=
watch
}
// Must run within the I/O thread.
func
(
w
*
Watcher
)
addWatch
(
pathname
string
,
flags
uint64
)
error
{
dir
,
err
:=
getDir
(
pathname
)
if
err
!=
nil
{
return
err
}
if
flags
&
sysFSONLYDIR
!=
0
&&
pathname
!=
dir
{
return
nil
}
ino
,
err
:=
getIno
(
dir
)
if
err
!=
nil
{
return
err
}
w
.
mu
.
Lock
()
watchEntry
:=
w
.
watches
.
get
(
ino
)
w
.
mu
.
Unlock
()
if
watchEntry
==
nil
{
if
_
,
e
:=
syscall
.
CreateIoCompletionPort
(
ino
.
handle
,
w
.
port
,
0
,
0
);
e
!=
nil
{
syscall
.
CloseHandle
(
ino
.
handle
)
return
os
.
NewSyscallError
(
"CreateIoCompletionPort"
,
e
)
}
watchEntry
=
&
watch
{
ino
:
ino
,
path
:
dir
,
names
:
make
(
map
[
string
]
uint64
),
}
w
.
mu
.
Lock
()
w
.
watches
.
set
(
ino
,
watchEntry
)
w
.
mu
.
Unlock
()
flags
|=
provisional
}
else
{
syscall
.
CloseHandle
(
ino
.
handle
)
}
if
pathname
==
dir
{
watchEntry
.
mask
|=
flags
}
else
{
watchEntry
.
names
[
filepath
.
Base
(
pathname
)]
|=
flags
}
if
err
=
w
.
startRead
(
watchEntry
);
err
!=
nil
{
return
err
}
if
pathname
==
dir
{
watchEntry
.
mask
&=
^
provisional
}
else
{
watchEntry
.
names
[
filepath
.
Base
(
pathname
)]
&=
^
provisional
}
return
nil
}
// Must run within the I/O thread.
func
(
w
*
Watcher
)
remWatch
(
pathname
string
)
error
{
dir
,
err
:=
getDir
(
pathname
)
if
err
!=
nil
{
return
err
}
ino
,
err
:=
getIno
(
dir
)
if
err
!=
nil
{
return
err
}
w
.
mu
.
Lock
()
watch
:=
w
.
watches
.
get
(
ino
)
w
.
mu
.
Unlock
()
if
watch
==
nil
{
return
fmt
.
Errorf
(
"can't remove non-existent watch for: %s"
,
pathname
)
}
if
pathname
==
dir
{
w
.
sendEvent
(
watch
.
path
,
watch
.
mask
&
sysFSIGNORED
)
watch
.
mask
=
0
}
else
{
name
:=
filepath
.
Base
(
pathname
)
w
.
sendEvent
(
filepath
.
Join
(
watch
.
path
,
name
),
watch
.
names
[
name
]
&
sysFSIGNORED
)
delete
(
watch
.
names
,
name
)
}
return
w
.
startRead
(
watch
)
}
// Must run within the I/O thread.
func
(
w
*
Watcher
)
deleteWatch
(
watch
*
watch
)
{
for
name
,
mask
:=
range
watch
.
names
{
if
mask
&
provisional
==
0
{
w
.
sendEvent
(
filepath
.
Join
(
watch
.
path
,
name
),
mask
&
sysFSIGNORED
)
}
delete
(
watch
.
names
,
name
)
}
if
watch
.
mask
!=
0
{
if
watch
.
mask
&
provisional
==
0
{
w
.
sendEvent
(
watch
.
path
,
watch
.
mask
&
sysFSIGNORED
)
}
watch
.
mask
=
0
}
}
// Must run within the I/O thread.
func
(
w
*
Watcher
)
startRead
(
watch
*
watch
)
error
{
if
e
:=
syscall
.
CancelIo
(
watch
.
ino
.
handle
);
e
!=
nil
{
w
.
Errors
<-
os
.
NewSyscallError
(
"CancelIo"
,
e
)
w
.
deleteWatch
(
watch
)
}
mask
:=
toWindowsFlags
(
watch
.
mask
)
for
_
,
m
:=
range
watch
.
names
{
mask
|=
toWindowsFlags
(
m
)
}
if
mask
==
0
{
if
e
:=
syscall
.
CloseHandle
(
watch
.
ino
.
handle
);
e
!=
nil
{
w
.
Errors
<-
os
.
NewSyscallError
(
"CloseHandle"
,
e
)
}
w
.
mu
.
Lock
()
delete
(
w
.
watches
[
watch
.
ino
.
volume
],
watch
.
ino
.
index
)
w
.
mu
.
Unlock
()
return
nil
}
e
:=
syscall
.
ReadDirectoryChanges
(
watch
.
ino
.
handle
,
&
watch
.
buf
[
0
],
uint32
(
unsafe
.
Sizeof
(
watch
.
buf
)),
false
,
mask
,
nil
,
&
watch
.
ov
,
0
)
if
e
!=
nil
{
err
:=
os
.
NewSyscallError
(
"ReadDirectoryChanges"
,
e
)
if
e
==
syscall
.
ERROR_ACCESS_DENIED
&&
watch
.
mask
&
provisional
==
0
{
// Watched directory was probably removed
if
w
.
sendEvent
(
watch
.
path
,
watch
.
mask
&
sysFSDELETESELF
)
{
if
watch
.
mask
&
sysFSONESHOT
!=
0
{
watch
.
mask
=
0
}
}
err
=
nil
}
w
.
deleteWatch
(
watch
)
w
.
startRead
(
watch
)
return
err
}
return
nil
}
// readEvents reads from the I/O completion port, converts the
// received events into Event objects and sends them via the Events channel.
// Entry point to the I/O thread.
func
(
w
*
Watcher
)
readEvents
()
{
var
(
n
,
key
uint32
ov
*
syscall
.
Overlapped
)
runtime
.
LockOSThread
()
for
{
e
:=
syscall
.
GetQueuedCompletionStatus
(
w
.
port
,
&
n
,
&
key
,
&
ov
,
syscall
.
INFINITE
)
watch
:=
(
*
watch
)(
unsafe
.
Pointer
(
ov
))
if
watch
==
nil
{
select
{
case
ch
:=
<-
w
.
quit
:
w
.
mu
.
Lock
()
var
indexes
[]
indexMap
for
_
,
index
:=
range
w
.
watches
{
indexes
=
append
(
indexes
,
index
)
}
w
.
mu
.
Unlock
()
for
_
,
index
:=
range
indexes
{
for
_
,
watch
:=
range
index
{
w
.
deleteWatch
(
watch
)
w
.
startRead
(
watch
)
}
}
var
err
error
if
e
:=
syscall
.
CloseHandle
(
w
.
port
);
e
!=
nil
{
err
=
os
.
NewSyscallError
(
"CloseHandle"
,
e
)
}
close
(
w
.
Events
)
close
(
w
.
Errors
)
ch
<-
err
return
case
in
:=
<-
w
.
input
:
switch
in
.
op
{
case
opAddWatch
:
in
.
reply
<-
w
.
addWatch
(
in
.
path
,
uint64
(
in
.
flags
))
case
opRemoveWatch
:
in
.
reply
<-
w
.
remWatch
(
in
.
path
)
}
default
:
}
continue
}
switch
e
{
case
syscall
.
ERROR_MORE_DATA
:
if
watch
==
nil
{
w
.
Errors
<-
errors
.
New
(
"ERROR_MORE_DATA has unexpectedly null lpOverlapped buffer"
)
}
else
{
// The i/o succeeded but the buffer is full.
// In theory we should be building up a full packet.
// In practice we can get away with just carrying on.
n
=
uint32
(
unsafe
.
Sizeof
(
watch
.
buf
))
}
case
syscall
.
ERROR_ACCESS_DENIED
:
// Watched directory was probably removed
w
.
sendEvent
(
watch
.
path
,
watch
.
mask
&
sysFSDELETESELF
)
w
.
deleteWatch
(
watch
)
w
.
startRead
(
watch
)
continue
case
syscall
.
ERROR_OPERATION_ABORTED
:
// CancelIo was called on this handle
continue
default
:
w
.
Errors
<-
os
.
NewSyscallError
(
"GetQueuedCompletionPort"
,
e
)
continue
case
nil
:
}
var
offset
uint32
for
{
if
n
==
0
{
w
.
Events
<-
newEvent
(
""
,
sysFSQOVERFLOW
)
w
.
Errors
<-
errors
.
New
(
"short read in readEvents()"
)
break
}
// Point "raw" to the event in the buffer
raw
:=
(
*
syscall
.
FileNotifyInformation
)(
unsafe
.
Pointer
(
&
watch
.
buf
[
offset
]))
buf
:=
(
*
[
syscall
.
MAX_PATH
]
uint16
)(
unsafe
.
Pointer
(
&
raw
.
FileName
))
name
:=
syscall
.
UTF16ToString
(
buf
[
:
raw
.
FileNameLength
/
2
])
fullname
:=
filepath
.
Join
(
watch
.
path
,
name
)
var
mask
uint64
switch
raw
.
Action
{
case
syscall
.
FILE_ACTION_REMOVED
:
mask
=
sysFSDELETESELF
case
syscall
.
FILE_ACTION_MODIFIED
:
mask
=
sysFSMODIFY
case
syscall
.
FILE_ACTION_RENAMED_OLD_NAME
:
watch
.
rename
=
name
case
syscall
.
FILE_ACTION_RENAMED_NEW_NAME
:
if
watch
.
names
[
watch
.
rename
]
!=
0
{
watch
.
names
[
name
]
|=
watch
.
names
[
watch
.
rename
]
delete
(
watch
.
names
,
watch
.
rename
)
mask
=
sysFSMOVESELF
}
}
sendNameEvent
:=
func
()
{
if
w
.
sendEvent
(
fullname
,
watch
.
names
[
name
]
&
mask
)
{
if
watch
.
names
[
name
]
&
sysFSONESHOT
!=
0
{
delete
(
watch
.
names
,
name
)
}
}
}
if
raw
.
Action
!=
syscall
.
FILE_ACTION_RENAMED_NEW_NAME
{
sendNameEvent
()
}
if
raw
.
Action
==
syscall
.
FILE_ACTION_REMOVED
{
w
.
sendEvent
(
fullname
,
watch
.
names
[
name
]
&
sysFSIGNORED
)
delete
(
watch
.
names
,
name
)
}
if
w
.
sendEvent
(
fullname
,
watch
.
mask
&
toFSnotifyFlags
(
raw
.
Action
))
{
if
watch
.
mask
&
sysFSONESHOT
!=
0
{
watch
.
mask
=
0
}
}
if
raw
.
Action
==
syscall
.
FILE_ACTION_RENAMED_NEW_NAME
{
fullname
=
filepath
.
Join
(
watch
.
path
,
watch
.
rename
)
sendNameEvent
()
}
// Move to the next event in the buffer
if
raw
.
NextEntryOffset
==
0
{
break
}
offset
+=
raw
.
NextEntryOffset
// Error!
if
offset
>=
n
{
w
.
Errors
<-
errors
.
New
(
"Windows system assumed buffer larger than it is, events have likely been missed."
)
break
}
}
if
err
:=
w
.
startRead
(
watch
);
err
!=
nil
{
w
.
Errors
<-
err
}
}
}
func
(
w
*
Watcher
)
sendEvent
(
name
string
,
mask
uint64
)
bool
{
if
mask
==
0
{
return
false
}
event
:=
newEvent
(
name
,
uint32
(
mask
))
select
{
case
ch
:=
<-
w
.
quit
:
w
.
quit
<-
ch
case
w
.
Events
<-
event
:
}
return
true
}
func
toWindowsFlags
(
mask
uint64
)
uint32
{
var
m
uint32
if
mask
&
sysFSACCESS
!=
0
{
m
|=
syscall
.
FILE_NOTIFY_CHANGE_LAST_ACCESS
}
if
mask
&
sysFSMODIFY
!=
0
{
m
|=
syscall
.
FILE_NOTIFY_CHANGE_LAST_WRITE
}
if
mask
&
sysFSATTRIB
!=
0
{
m
|=
syscall
.
FILE_NOTIFY_CHANGE_ATTRIBUTES
}
if
mask
&
(
sysFSMOVE
|
sysFSCREATE
|
sysFSDELETE
)
!=
0
{
m
|=
syscall
.
FILE_NOTIFY_CHANGE_FILE_NAME
|
syscall
.
FILE_NOTIFY_CHANGE_DIR_NAME
}
return
m
}
func
toFSnotifyFlags
(
action
uint32
)
uint64
{
switch
action
{
case
syscall
.
FILE_ACTION_ADDED
:
return
sysFSCREATE
case
syscall
.
FILE_ACTION_REMOVED
:
return
sysFSDELETE
case
syscall
.
FILE_ACTION_MODIFIED
:
return
sysFSMODIFY
case
syscall
.
FILE_ACTION_RENAMED_OLD_NAME
:
return
sysFSMOVEDFROM
case
syscall
.
FILE_ACTION_RENAMED_NEW_NAME
:
return
sysFSMOVEDTO
}
return
0
}
wcfs/vendor/lab.nexedi.com/kirr/go123/xcontainer/list/list.go
deleted
100644 → 0
View file @
de1db2fe
// Copyright (C) 2017-2019 Nexedi SA and Contributors.
// Kirill Smelkov <kirr@nexedi.com>
//
// This program is free software: you can Use, Study, Modify and Redistribute
// it under the terms of the GNU General Public License version 3, or (at your
// option) any later version, as published by the Free Software Foundation.
//
// You can also Link and Combine this program with other software covered by
// the terms of any of the Free Software licenses or any of the Open Source
// Initiative approved licenses and Convey the resulting work. Corresponding
// source of such a combination shall include the source code for all other
// software used.
//
// This program is distributed WITHOUT ANY WARRANTY; without even the implied
// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
//
// See COPYING file for full licensing terms.
// See https://www.nexedi.com/licensing for rationale and options.
// Package list provides intrusive double-linked lists.
//
// Go standard library has container/list package which already provides
// double-linked lists. However in that implementation list itself is kept
// separate from data structures representing elements. This package provides
// alternative approach where elements embed necessary list heads which is
// sometimes more convenient, for example when one wants to move a list
// element in O(1) starting from pointer to just its data.
//
// TODO doc how to get to container of list head via unsafe.OffsetOf.
package
list
// Head is a list head entry for an element in an intrusive doubly-linked list.
//
// Zero HEAD value is NOT valid - always call Init() to initialize a head
// before using it.
type
Head
struct
{
next
,
prev
*
Head
}
func
(
h
*
Head
)
Next
()
*
Head
{
return
h
.
next
}
func
(
h
*
Head
)
Prev
()
*
Head
{
return
h
.
prev
}
// Init initializes a head making it point to itself via .next and .prev .
func
(
h
*
Head
)
Init
()
{
h
.
next
=
h
h
.
prev
=
h
}
// Delete deletes h from its list.
func
(
h
*
Head
)
Delete
()
{
h
.
next
.
prev
=
h
.
prev
h
.
prev
.
next
=
h
.
next
h
.
Init
()
}
// MoveBefore moves a to be before b.
//
// XXX ok to move if a was not previously on the list?
func
(
a
*
Head
)
MoveBefore
(
b
*
Head
)
{
a
.
Delete
()
a
.
next
=
b
a
.
prev
=
b
.
prev
b
.
prev
=
a
a
.
prev
.
next
=
a
}
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