bagage/internal/encoding/ssh/filexfer/permissions.go

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2021-11-19 18:54:49 +00:00
package filexfer
// FileMode represents a files mode and permission bits.
// The bits are defined according to POSIX standards,
// and may not apply to the OS being built for.
type FileMode uint32
// Permission flags, defined here to avoid potential inconsistencies in individual OS implementations.
const (
ModePerm FileMode = 0o0777 // S_IRWXU | S_IRWXG | S_IRWXO
ModeUserRead FileMode = 0o0400 // S_IRUSR
ModeUserWrite FileMode = 0o0200 // S_IWUSR
ModeUserExec FileMode = 0o0100 // S_IXUSR
ModeGroupRead FileMode = 0o0040 // S_IRGRP
ModeGroupWrite FileMode = 0o0020 // S_IWGRP
ModeGroupExec FileMode = 0o0010 // S_IXGRP
ModeOtherRead FileMode = 0o0004 // S_IROTH
ModeOtherWrite FileMode = 0o0002 // S_IWOTH
ModeOtherExec FileMode = 0o0001 // S_IXOTH
ModeSetUID FileMode = 0o4000 // S_ISUID
ModeSetGID FileMode = 0o2000 // S_ISGID
ModeSticky FileMode = 0o1000 // S_ISVTX
ModeType FileMode = 0xF000 // S_IFMT
ModeNamedPipe FileMode = 0x1000 // S_IFIFO
ModeCharDevice FileMode = 0x2000 // S_IFCHR
ModeDir FileMode = 0x4000 // S_IFDIR
ModeDevice FileMode = 0x6000 // S_IFBLK
ModeRegular FileMode = 0x8000 // S_IFREG
ModeSymlink FileMode = 0xA000 // S_IFLNK
ModeSocket FileMode = 0xC000 // S_IFSOCK
)
// IsDir reports whether m describes a directory.
// That is, it tests for m.Type() == ModeDir.
func (m FileMode) IsDir() bool {
return (m & ModeType) == ModeDir
}
// IsRegular reports whether m describes a regular file.
// That is, it tests for m.Type() == ModeRegular
func (m FileMode) IsRegular() bool {
return (m & ModeType) == ModeRegular
}
// Perm returns the POSIX permission bits in m (m & ModePerm).
func (m FileMode) Perm() FileMode {
return (m & ModePerm)
}
// Type returns the type bits in m (m & ModeType).
func (m FileMode) Type() FileMode {
return (m & ModeType)
}
// String returns a `-rwxrwxrwx` style string representing the `ls -l` POSIX permissions string.
func (m FileMode) String() string {
var buf [10]byte
switch m.Type() {
case ModeRegular:
buf[0] = '-'
case ModeDir:
buf[0] = 'd'
case ModeSymlink:
buf[0] = 'l'
case ModeDevice:
buf[0] = 'b'
case ModeCharDevice:
buf[0] = 'c'
case ModeNamedPipe:
buf[0] = 'p'
case ModeSocket:
buf[0] = 's'
default:
buf[0] = '?'
}
const rwx = "rwxrwxrwx"
for i, c := range rwx {
if m&(1<<uint(9-1-i)) != 0 {
buf[i+1] = byte(c)
} else {
buf[i+1] = '-'
}
}
if m&ModeSetUID != 0 {
if buf[3] == 'x' {
buf[3] = 's'
} else {
buf[3] = 'S'
}
}
if m&ModeSetGID != 0 {
if buf[6] == 'x' {
buf[6] = 's'
} else {
buf[6] = 'S'
}
}
if m&ModeSticky != 0 {
if buf[9] == 'x' {
buf[9] = 't'
} else {
buf[9] = 'T'
}
}
return string(buf[:])
}