2019-04-29 21:25:05 +00:00
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// Copyright 2018 The gVisor Authors.
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2018-04-27 17:37:02 +00:00
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package linux
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import (
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"fmt"
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"strings"
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2019-06-13 23:49:09 +00:00
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"gvisor.dev/gvisor/pkg/abi"
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"gvisor.dev/gvisor/pkg/binary"
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2018-04-27 17:37:02 +00:00
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)
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// Constants for open(2).
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const (
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2018-07-27 19:26:42 +00:00
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O_ACCMODE = 00000003
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O_RDONLY = 00000000
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O_WRONLY = 00000001
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O_RDWR = 00000002
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2018-08-09 23:49:23 +00:00
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O_CREAT = 00000100
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O_EXCL = 00000200
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O_NOCTTY = 00000400
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O_TRUNC = 00001000
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2018-07-27 19:26:42 +00:00
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O_APPEND = 00002000
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O_NONBLOCK = 00004000
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O_ASYNC = 00020000
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O_DIRECT = 00040000
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O_LARGEFILE = 00100000
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O_DIRECTORY = 00200000
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2018-09-05 16:20:18 +00:00
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O_NOFOLLOW = 00400000
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2018-07-27 19:26:42 +00:00
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O_CLOEXEC = 02000000
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O_SYNC = 04010000
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O_PATH = 010000000
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2018-04-27 17:37:02 +00:00
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)
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// Constants for fstatat(2).
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const (
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AT_SYMLINK_NOFOLLOW = 0x100
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)
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// Constants for mount(2).
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const (
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MS_RDONLY = 0x1
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MS_NOSUID = 0x2
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MS_NODEV = 0x4
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MS_NOEXEC = 0x8
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MS_SYNCHRONOUS = 0x10
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MS_REMOUNT = 0x20
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MS_MANDLOCK = 0x40
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MS_DIRSYNC = 0x80
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MS_NOATIME = 0x400
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MS_NODIRATIME = 0x800
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MS_BIND = 0x1000
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MS_MOVE = 0x2000
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MS_REC = 0x4000
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MS_POSIXACL = 0x10000
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MS_UNBINDABLE = 0x20000
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MS_PRIVATE = 0x40000
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MS_SLAVE = 0x80000
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MS_SHARED = 0x100000
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MS_RELATIME = 0x200000
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MS_KERNMOUNT = 0x400000
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MS_I_VERSION = 0x800000
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MS_STRICTATIME = 0x1000000
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MS_MGC_VAL = 0xC0ED0000
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MS_MGC_MSK = 0xffff0000
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)
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// Constants for umount2(2).
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const (
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MNT_FORCE = 0x1
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MNT_DETACH = 0x2
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MNT_EXPIRE = 0x4
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UMOUNT_NOFOLLOW = 0x8
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)
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// Constants for unlinkat(2).
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const (
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AT_REMOVEDIR = 0x200
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)
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// Constants for linkat(2) and fchownat(2).
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const (
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AT_SYMLINK_FOLLOW = 0x400
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AT_EMPTY_PATH = 0x1000
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)
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// Constants for all file-related ...at(2) syscalls.
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const (
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AT_FDCWD = -100
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)
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// Special values for the ns field in utimensat(2).
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const (
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UTIME_NOW = ((1 << 30) - 1)
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UTIME_OMIT = ((1 << 30) - 2)
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)
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// MaxSymlinkTraversals is the maximum number of links that will be followed by
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// the kernel to resolve a symlink.
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const MaxSymlinkTraversals = 40
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// Constants for flock(2).
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const (
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LOCK_SH = 1 // shared lock
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LOCK_EX = 2 // exclusive lock
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LOCK_NB = 4 // or'd with one of the above to prevent blocking
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LOCK_UN = 8 // remove lock
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)
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// Values for mode_t.
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const (
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FileTypeMask = 0170000
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ModeSocket = 0140000
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ModeSymlink = 0120000
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ModeRegular = 0100000
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ModeBlockDevice = 060000
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ModeDirectory = 040000
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ModeCharacterDevice = 020000
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ModeNamedPipe = 010000
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ModeSetUID = 04000
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ModeSetGID = 02000
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ModeSticky = 01000
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ModeUserAll = 0700
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ModeUserRead = 0400
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ModeUserWrite = 0200
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ModeUserExec = 0100
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ModeGroupAll = 0070
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ModeGroupRead = 0040
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ModeGroupWrite = 0020
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ModeGroupExec = 0010
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ModeOtherAll = 0007
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ModeOtherRead = 0004
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ModeOtherWrite = 0002
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ModeOtherExec = 0001
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PermissionsMask = 0777
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)
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2018-11-26 17:49:53 +00:00
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// Values for preadv2/pwritev2.
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const (
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2018-12-19 21:14:53 +00:00
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RWF_HIPRI = 0x00000001
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RWF_DSYNC = 0x00000002
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RWF_SYNC = 0x00000004
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RWF_VALID = RWF_HIPRI | RWF_DSYNC | RWF_SYNC
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2018-11-26 17:49:53 +00:00
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)
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2018-04-27 17:37:02 +00:00
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// Stat represents struct stat.
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type Stat struct {
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Dev uint64
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Ino uint64
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Nlink uint64
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Mode uint32
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UID uint32
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GID uint32
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X_pad0 int32
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Rdev uint64
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Size int64
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Blksize int64
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Blocks int64
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ATime Timespec
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MTime Timespec
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CTime Timespec
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X_unused [3]int64
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}
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2019-02-08 23:47:25 +00:00
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// SizeOfStat is the size of a Stat struct.
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var SizeOfStat = binary.Size(Stat{})
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2018-04-27 17:37:02 +00:00
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// FileMode represents a mode_t.
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type FileMode uint
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// Permissions returns just the permission bits.
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func (m FileMode) Permissions() FileMode {
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return m & PermissionsMask
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}
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// FileType returns just the file type bits.
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func (m FileMode) FileType() FileMode {
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return m & FileTypeMask
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}
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// ExtraBits returns everything but the file type and permission bits.
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func (m FileMode) ExtraBits() FileMode {
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return m &^ (PermissionsMask | FileTypeMask)
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}
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// String returns a string representation of m.
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func (m FileMode) String() string {
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var s []string
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if ft := m.FileType(); ft != 0 {
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s = append(s, fileType.Parse(uint64(ft)))
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}
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if eb := m.ExtraBits(); eb != 0 {
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s = append(s, modeExtraBits.Parse(uint64(eb)))
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}
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s = append(s, fmt.Sprintf("0o%o", m.Permissions()))
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return strings.Join(s, "|")
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}
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var modeExtraBits = abi.FlagSet{
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{
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Flag: ModeSetUID,
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Name: "S_ISUID",
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},
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{
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Flag: ModeSetGID,
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Name: "S_ISGID",
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},
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{
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Flag: ModeSticky,
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Name: "S_ISVTX",
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},
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}
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var fileType = abi.ValueSet{
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2018-12-06 19:42:23 +00:00
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ModeSocket: "S_IFSOCK",
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ModeSymlink: "S_IFLINK",
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ModeRegular: "S_IFREG",
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ModeBlockDevice: "S_IFBLK",
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ModeDirectory: "S_IFDIR",
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ModeCharacterDevice: "S_IFCHR",
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ModeNamedPipe: "S_IFIFO",
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2018-04-27 17:37:02 +00:00
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}
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2019-03-26 23:15:55 +00:00
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// Constants for memfd_create(2). Source: include/uapi/linux/memfd.h
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const (
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MFD_CLOEXEC = 0x0001
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MFD_ALLOW_SEALING = 0x0002
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)
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// Constants related to file seals. Source: include/uapi/{asm-generic,linux}/fcntl.h
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const (
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F_LINUX_SPECIFIC_BASE = 1024
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F_ADD_SEALS = F_LINUX_SPECIFIC_BASE + 9
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F_GET_SEALS = F_LINUX_SPECIFIC_BASE + 10
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F_SEAL_SEAL = 0x0001 // Prevent further seals from being set.
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F_SEAL_SHRINK = 0x0002 // Prevent file from shrinking.
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F_SEAL_GROW = 0x0004 // Prevent file from growing.
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F_SEAL_WRITE = 0x0008 // Prevent writes.
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)
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2019-05-09 22:34:44 +00:00
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// Constants related to fallocate(2). Source: include/uapi/linux/falloc.h
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const (
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FALLOC_FL_KEEP_SIZE = 0x01
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FALLOC_FL_PUNCH_HOLE = 0x02
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FALLOC_FL_NO_HIDE_STALE = 0x04
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FALLOC_FL_COLLAPSE_RANGE = 0x08
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FALLOC_FL_ZERO_RANGE = 0x10
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FALLOC_FL_INSERT_RANGE = 0x20
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FALLOC_FL_UNSHARE_RANGE = 0x40
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)
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