rebase: update K8s packages to v0.32.1

Update K8s packages in go.mod to v0.32.1

Signed-off-by: Praveen M <m.praveen@ibm.com>
This commit is contained in:
Praveen M
2025-01-16 09:41:46 +05:30
committed by mergify[bot]
parent 5aef21ea4e
commit 7eb99fc6c9
2442 changed files with 273386 additions and 47788 deletions

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// This package contains Win32 filesystem functionality.
package fs

262
vendor/github.com/Microsoft/go-winio/internal/fs/fs.go generated vendored Normal file
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//go:build windows
package fs
import (
"golang.org/x/sys/windows"
"github.com/Microsoft/go-winio/internal/stringbuffer"
)
//go:generate go run github.com/Microsoft/go-winio/tools/mkwinsyscall -output zsyscall_windows.go fs.go
// https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilew
//sys CreateFile(name string, access AccessMask, mode FileShareMode, sa *windows.SecurityAttributes, createmode FileCreationDisposition, attrs FileFlagOrAttribute, templatefile windows.Handle) (handle windows.Handle, err error) [failretval==windows.InvalidHandle] = CreateFileW
const NullHandle windows.Handle = 0
// AccessMask defines standard, specific, and generic rights.
//
// Used with CreateFile and NtCreateFile (and co.).
//
// Bitmask:
// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
// +---------------+---------------+-------------------------------+
// |G|G|G|G|Resvd|A| StandardRights| SpecificRights |
// |R|W|E|A| |S| | |
// +-+-------------+---------------+-------------------------------+
//
// GR Generic Read
// GW Generic Write
// GE Generic Exectue
// GA Generic All
// Resvd Reserved
// AS Access Security System
//
// https://learn.microsoft.com/en-us/windows/win32/secauthz/access-mask
//
// https://learn.microsoft.com/en-us/windows/win32/secauthz/generic-access-rights
//
// https://learn.microsoft.com/en-us/windows/win32/fileio/file-access-rights-constants
type AccessMask = windows.ACCESS_MASK
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
// Not actually any.
//
// For CreateFile: "query certain metadata such as file, directory, or device attributes without accessing that file or device"
// https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilew#parameters
FILE_ANY_ACCESS AccessMask = 0
GENERIC_READ AccessMask = 0x8000_0000
GENERIC_WRITE AccessMask = 0x4000_0000
GENERIC_EXECUTE AccessMask = 0x2000_0000
GENERIC_ALL AccessMask = 0x1000_0000
ACCESS_SYSTEM_SECURITY AccessMask = 0x0100_0000
// Specific Object Access
// from ntioapi.h
FILE_READ_DATA AccessMask = (0x0001) // file & pipe
FILE_LIST_DIRECTORY AccessMask = (0x0001) // directory
FILE_WRITE_DATA AccessMask = (0x0002) // file & pipe
FILE_ADD_FILE AccessMask = (0x0002) // directory
FILE_APPEND_DATA AccessMask = (0x0004) // file
FILE_ADD_SUBDIRECTORY AccessMask = (0x0004) // directory
FILE_CREATE_PIPE_INSTANCE AccessMask = (0x0004) // named pipe
FILE_READ_EA AccessMask = (0x0008) // file & directory
FILE_READ_PROPERTIES AccessMask = FILE_READ_EA
FILE_WRITE_EA AccessMask = (0x0010) // file & directory
FILE_WRITE_PROPERTIES AccessMask = FILE_WRITE_EA
FILE_EXECUTE AccessMask = (0x0020) // file
FILE_TRAVERSE AccessMask = (0x0020) // directory
FILE_DELETE_CHILD AccessMask = (0x0040) // directory
FILE_READ_ATTRIBUTES AccessMask = (0x0080) // all
FILE_WRITE_ATTRIBUTES AccessMask = (0x0100) // all
FILE_ALL_ACCESS AccessMask = (STANDARD_RIGHTS_REQUIRED | SYNCHRONIZE | 0x1FF)
FILE_GENERIC_READ AccessMask = (STANDARD_RIGHTS_READ | FILE_READ_DATA | FILE_READ_ATTRIBUTES | FILE_READ_EA | SYNCHRONIZE)
FILE_GENERIC_WRITE AccessMask = (STANDARD_RIGHTS_WRITE | FILE_WRITE_DATA | FILE_WRITE_ATTRIBUTES | FILE_WRITE_EA | FILE_APPEND_DATA | SYNCHRONIZE)
FILE_GENERIC_EXECUTE AccessMask = (STANDARD_RIGHTS_EXECUTE | FILE_READ_ATTRIBUTES | FILE_EXECUTE | SYNCHRONIZE)
SPECIFIC_RIGHTS_ALL AccessMask = 0x0000FFFF
// Standard Access
// from ntseapi.h
DELETE AccessMask = 0x0001_0000
READ_CONTROL AccessMask = 0x0002_0000
WRITE_DAC AccessMask = 0x0004_0000
WRITE_OWNER AccessMask = 0x0008_0000
SYNCHRONIZE AccessMask = 0x0010_0000
STANDARD_RIGHTS_REQUIRED AccessMask = 0x000F_0000
STANDARD_RIGHTS_READ AccessMask = READ_CONTROL
STANDARD_RIGHTS_WRITE AccessMask = READ_CONTROL
STANDARD_RIGHTS_EXECUTE AccessMask = READ_CONTROL
STANDARD_RIGHTS_ALL AccessMask = 0x001F_0000
)
type FileShareMode uint32
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
FILE_SHARE_NONE FileShareMode = 0x00
FILE_SHARE_READ FileShareMode = 0x01
FILE_SHARE_WRITE FileShareMode = 0x02
FILE_SHARE_DELETE FileShareMode = 0x04
FILE_SHARE_VALID_FLAGS FileShareMode = 0x07
)
type FileCreationDisposition uint32
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
// from winbase.h
CREATE_NEW FileCreationDisposition = 0x01
CREATE_ALWAYS FileCreationDisposition = 0x02
OPEN_EXISTING FileCreationDisposition = 0x03
OPEN_ALWAYS FileCreationDisposition = 0x04
TRUNCATE_EXISTING FileCreationDisposition = 0x05
)
// Create disposition values for NtCreate*
type NTFileCreationDisposition uint32
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
// From ntioapi.h
FILE_SUPERSEDE NTFileCreationDisposition = 0x00
FILE_OPEN NTFileCreationDisposition = 0x01
FILE_CREATE NTFileCreationDisposition = 0x02
FILE_OPEN_IF NTFileCreationDisposition = 0x03
FILE_OVERWRITE NTFileCreationDisposition = 0x04
FILE_OVERWRITE_IF NTFileCreationDisposition = 0x05
FILE_MAXIMUM_DISPOSITION NTFileCreationDisposition = 0x05
)
// CreateFile and co. take flags or attributes together as one parameter.
// Define alias until we can use generics to allow both
//
// https://learn.microsoft.com/en-us/windows/win32/fileio/file-attribute-constants
type FileFlagOrAttribute uint32
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
// from winnt.h
FILE_FLAG_WRITE_THROUGH FileFlagOrAttribute = 0x8000_0000
FILE_FLAG_OVERLAPPED FileFlagOrAttribute = 0x4000_0000
FILE_FLAG_NO_BUFFERING FileFlagOrAttribute = 0x2000_0000
FILE_FLAG_RANDOM_ACCESS FileFlagOrAttribute = 0x1000_0000
FILE_FLAG_SEQUENTIAL_SCAN FileFlagOrAttribute = 0x0800_0000
FILE_FLAG_DELETE_ON_CLOSE FileFlagOrAttribute = 0x0400_0000
FILE_FLAG_BACKUP_SEMANTICS FileFlagOrAttribute = 0x0200_0000
FILE_FLAG_POSIX_SEMANTICS FileFlagOrAttribute = 0x0100_0000
FILE_FLAG_OPEN_REPARSE_POINT FileFlagOrAttribute = 0x0020_0000
FILE_FLAG_OPEN_NO_RECALL FileFlagOrAttribute = 0x0010_0000
FILE_FLAG_FIRST_PIPE_INSTANCE FileFlagOrAttribute = 0x0008_0000
)
// NtCreate* functions take a dedicated CreateOptions parameter.
//
// https://learn.microsoft.com/en-us/windows/win32/api/Winternl/nf-winternl-ntcreatefile
//
// https://learn.microsoft.com/en-us/windows/win32/devnotes/nt-create-named-pipe-file
type NTCreateOptions uint32
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
// From ntioapi.h
FILE_DIRECTORY_FILE NTCreateOptions = 0x0000_0001
FILE_WRITE_THROUGH NTCreateOptions = 0x0000_0002
FILE_SEQUENTIAL_ONLY NTCreateOptions = 0x0000_0004
FILE_NO_INTERMEDIATE_BUFFERING NTCreateOptions = 0x0000_0008
FILE_SYNCHRONOUS_IO_ALERT NTCreateOptions = 0x0000_0010
FILE_SYNCHRONOUS_IO_NONALERT NTCreateOptions = 0x0000_0020
FILE_NON_DIRECTORY_FILE NTCreateOptions = 0x0000_0040
FILE_CREATE_TREE_CONNECTION NTCreateOptions = 0x0000_0080
FILE_COMPLETE_IF_OPLOCKED NTCreateOptions = 0x0000_0100
FILE_NO_EA_KNOWLEDGE NTCreateOptions = 0x0000_0200
FILE_DISABLE_TUNNELING NTCreateOptions = 0x0000_0400
FILE_RANDOM_ACCESS NTCreateOptions = 0x0000_0800
FILE_DELETE_ON_CLOSE NTCreateOptions = 0x0000_1000
FILE_OPEN_BY_FILE_ID NTCreateOptions = 0x0000_2000
FILE_OPEN_FOR_BACKUP_INTENT NTCreateOptions = 0x0000_4000
FILE_NO_COMPRESSION NTCreateOptions = 0x0000_8000
)
type FileSQSFlag = FileFlagOrAttribute
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
// from winbase.h
SECURITY_ANONYMOUS FileSQSFlag = FileSQSFlag(SecurityAnonymous << 16)
SECURITY_IDENTIFICATION FileSQSFlag = FileSQSFlag(SecurityIdentification << 16)
SECURITY_IMPERSONATION FileSQSFlag = FileSQSFlag(SecurityImpersonation << 16)
SECURITY_DELEGATION FileSQSFlag = FileSQSFlag(SecurityDelegation << 16)
SECURITY_SQOS_PRESENT FileSQSFlag = 0x0010_0000
SECURITY_VALID_SQOS_FLAGS FileSQSFlag = 0x001F_0000
)
// GetFinalPathNameByHandle flags
//
// https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfinalpathnamebyhandlew#parameters
type GetFinalPathFlag uint32
//nolint:revive // SNAKE_CASE is not idiomatic in Go, but aligned with Win32 API.
const (
GetFinalPathDefaultFlag GetFinalPathFlag = 0x0
FILE_NAME_NORMALIZED GetFinalPathFlag = 0x0
FILE_NAME_OPENED GetFinalPathFlag = 0x8
VOLUME_NAME_DOS GetFinalPathFlag = 0x0
VOLUME_NAME_GUID GetFinalPathFlag = 0x1
VOLUME_NAME_NT GetFinalPathFlag = 0x2
VOLUME_NAME_NONE GetFinalPathFlag = 0x4
)
// getFinalPathNameByHandle facilitates calling the Windows API GetFinalPathNameByHandle
// with the given handle and flags. It transparently takes care of creating a buffer of the
// correct size for the call.
//
// https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfinalpathnamebyhandlew
func GetFinalPathNameByHandle(h windows.Handle, flags GetFinalPathFlag) (string, error) {
b := stringbuffer.NewWString()
//TODO: can loop infinitely if Win32 keeps returning the same (or a larger) n?
for {
n, err := windows.GetFinalPathNameByHandle(h, b.Pointer(), b.Cap(), uint32(flags))
if err != nil {
return "", err
}
// If the buffer wasn't large enough, n will be the total size needed (including null terminator).
// Resize and try again.
if n > b.Cap() {
b.ResizeTo(n)
continue
}
// If the buffer is large enough, n will be the size not including the null terminator.
// Convert to a Go string and return.
return b.String(), nil
}
}

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package fs
// https://learn.microsoft.com/en-us/windows/win32/api/winnt/ne-winnt-security_impersonation_level
type SecurityImpersonationLevel int32 // C default enums underlying type is `int`, which is Go `int32`
// Impersonation levels
const (
SecurityAnonymous SecurityImpersonationLevel = 0
SecurityIdentification SecurityImpersonationLevel = 1
SecurityImpersonation SecurityImpersonationLevel = 2
SecurityDelegation SecurityImpersonationLevel = 3
)

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//go:build windows
// Code generated by 'go generate' using "github.com/Microsoft/go-winio/tools/mkwinsyscall"; DO NOT EDIT.
package fs
import (
"syscall"
"unsafe"
"golang.org/x/sys/windows"
)
var _ unsafe.Pointer
// Do the interface allocations only once for common
// Errno values.
const (
errnoERROR_IO_PENDING = 997
)
var (
errERROR_IO_PENDING error = syscall.Errno(errnoERROR_IO_PENDING)
errERROR_EINVAL error = syscall.EINVAL
)
// errnoErr returns common boxed Errno values, to prevent
// allocations at runtime.
func errnoErr(e syscall.Errno) error {
switch e {
case 0:
return errERROR_EINVAL
case errnoERROR_IO_PENDING:
return errERROR_IO_PENDING
}
return e
}
var (
modkernel32 = windows.NewLazySystemDLL("kernel32.dll")
procCreateFileW = modkernel32.NewProc("CreateFileW")
)
func CreateFile(name string, access AccessMask, mode FileShareMode, sa *windows.SecurityAttributes, createmode FileCreationDisposition, attrs FileFlagOrAttribute, templatefile windows.Handle) (handle windows.Handle, err error) {
var _p0 *uint16
_p0, err = syscall.UTF16PtrFromString(name)
if err != nil {
return
}
return _CreateFile(_p0, access, mode, sa, createmode, attrs, templatefile)
}
func _CreateFile(name *uint16, access AccessMask, mode FileShareMode, sa *windows.SecurityAttributes, createmode FileCreationDisposition, attrs FileFlagOrAttribute, templatefile windows.Handle) (handle windows.Handle, err error) {
r0, _, e1 := syscall.SyscallN(procCreateFileW.Addr(), uintptr(unsafe.Pointer(name)), uintptr(access), uintptr(mode), uintptr(unsafe.Pointer(sa)), uintptr(createmode), uintptr(attrs), uintptr(templatefile))
handle = windows.Handle(r0)
if handle == windows.InvalidHandle {
err = errnoErr(e1)
}
return
}

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package socket
import (
"unsafe"
)
// RawSockaddr allows structs to be used with [Bind] and [ConnectEx]. The
// struct must meet the Win32 sockaddr requirements specified here:
// https://docs.microsoft.com/en-us/windows/win32/winsock/sockaddr-2
//
// Specifically, the struct size must be least larger than an int16 (unsigned short)
// for the address family.
type RawSockaddr interface {
// Sockaddr returns a pointer to the RawSockaddr and its struct size, allowing
// for the RawSockaddr's data to be overwritten by syscalls (if necessary).
//
// It is the callers responsibility to validate that the values are valid; invalid
// pointers or size can cause a panic.
Sockaddr() (unsafe.Pointer, int32, error)
}

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//go:build windows
package socket
import (
"errors"
"fmt"
"net"
"sync"
"syscall"
"unsafe"
"github.com/Microsoft/go-winio/pkg/guid"
"golang.org/x/sys/windows"
)
//go:generate go run github.com/Microsoft/go-winio/tools/mkwinsyscall -output zsyscall_windows.go socket.go
//sys getsockname(s windows.Handle, name unsafe.Pointer, namelen *int32) (err error) [failretval==socketError] = ws2_32.getsockname
//sys getpeername(s windows.Handle, name unsafe.Pointer, namelen *int32) (err error) [failretval==socketError] = ws2_32.getpeername
//sys bind(s windows.Handle, name unsafe.Pointer, namelen int32) (err error) [failretval==socketError] = ws2_32.bind
const socketError = uintptr(^uint32(0))
var (
// todo(helsaawy): create custom error types to store the desired vs actual size and addr family?
ErrBufferSize = errors.New("buffer size")
ErrAddrFamily = errors.New("address family")
ErrInvalidPointer = errors.New("invalid pointer")
ErrSocketClosed = fmt.Errorf("socket closed: %w", net.ErrClosed)
)
// todo(helsaawy): replace these with generics, ie: GetSockName[S RawSockaddr](s windows.Handle) (S, error)
// GetSockName writes the local address of socket s to the [RawSockaddr] rsa.
// If rsa is not large enough, the [windows.WSAEFAULT] is returned.
func GetSockName(s windows.Handle, rsa RawSockaddr) error {
ptr, l, err := rsa.Sockaddr()
if err != nil {
return fmt.Errorf("could not retrieve socket pointer and size: %w", err)
}
// although getsockname returns WSAEFAULT if the buffer is too small, it does not set
// &l to the correct size, so--apart from doubling the buffer repeatedly--there is no remedy
return getsockname(s, ptr, &l)
}
// GetPeerName returns the remote address the socket is connected to.
//
// See [GetSockName] for more information.
func GetPeerName(s windows.Handle, rsa RawSockaddr) error {
ptr, l, err := rsa.Sockaddr()
if err != nil {
return fmt.Errorf("could not retrieve socket pointer and size: %w", err)
}
return getpeername(s, ptr, &l)
}
func Bind(s windows.Handle, rsa RawSockaddr) (err error) {
ptr, l, err := rsa.Sockaddr()
if err != nil {
return fmt.Errorf("could not retrieve socket pointer and size: %w", err)
}
return bind(s, ptr, l)
}
// "golang.org/x/sys/windows".ConnectEx and .Bind only accept internal implementations of the
// their sockaddr interface, so they cannot be used with HvsockAddr
// Replicate functionality here from
// https://cs.opensource.google/go/x/sys/+/master:windows/syscall_windows.go
// The function pointers to `AcceptEx`, `ConnectEx` and `GetAcceptExSockaddrs` must be loaded at
// runtime via a WSAIoctl call:
// https://docs.microsoft.com/en-us/windows/win32/api/Mswsock/nc-mswsock-lpfn_connectex#remarks
type runtimeFunc struct {
id guid.GUID
once sync.Once
addr uintptr
err error
}
func (f *runtimeFunc) Load() error {
f.once.Do(func() {
var s windows.Handle
s, f.err = windows.Socket(windows.AF_INET, windows.SOCK_STREAM, windows.IPPROTO_TCP)
if f.err != nil {
return
}
defer windows.CloseHandle(s) //nolint:errcheck
var n uint32
f.err = windows.WSAIoctl(s,
windows.SIO_GET_EXTENSION_FUNCTION_POINTER,
(*byte)(unsafe.Pointer(&f.id)),
uint32(unsafe.Sizeof(f.id)),
(*byte)(unsafe.Pointer(&f.addr)),
uint32(unsafe.Sizeof(f.addr)),
&n,
nil, // overlapped
0, // completionRoutine
)
})
return f.err
}
var (
// todo: add `AcceptEx` and `GetAcceptExSockaddrs`
WSAID_CONNECTEX = guid.GUID{ //revive:disable-line:var-naming ALL_CAPS
Data1: 0x25a207b9,
Data2: 0xddf3,
Data3: 0x4660,
Data4: [8]byte{0x8e, 0xe9, 0x76, 0xe5, 0x8c, 0x74, 0x06, 0x3e},
}
connectExFunc = runtimeFunc{id: WSAID_CONNECTEX}
)
func ConnectEx(
fd windows.Handle,
rsa RawSockaddr,
sendBuf *byte,
sendDataLen uint32,
bytesSent *uint32,
overlapped *windows.Overlapped,
) error {
if err := connectExFunc.Load(); err != nil {
return fmt.Errorf("failed to load ConnectEx function pointer: %w", err)
}
ptr, n, err := rsa.Sockaddr()
if err != nil {
return err
}
return connectEx(fd, ptr, n, sendBuf, sendDataLen, bytesSent, overlapped)
}
// BOOL LpfnConnectex(
// [in] SOCKET s,
// [in] const sockaddr *name,
// [in] int namelen,
// [in, optional] PVOID lpSendBuffer,
// [in] DWORD dwSendDataLength,
// [out] LPDWORD lpdwBytesSent,
// [in] LPOVERLAPPED lpOverlapped
// )
func connectEx(
s windows.Handle,
name unsafe.Pointer,
namelen int32,
sendBuf *byte,
sendDataLen uint32,
bytesSent *uint32,
overlapped *windows.Overlapped,
) (err error) {
r1, _, e1 := syscall.SyscallN(connectExFunc.addr,
uintptr(s),
uintptr(name),
uintptr(namelen),
uintptr(unsafe.Pointer(sendBuf)),
uintptr(sendDataLen),
uintptr(unsafe.Pointer(bytesSent)),
uintptr(unsafe.Pointer(overlapped)),
)
if r1 == 0 {
if e1 != 0 {
err = error(e1)
} else {
err = syscall.EINVAL
}
}
return err
}

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//go:build windows
// Code generated by 'go generate' using "github.com/Microsoft/go-winio/tools/mkwinsyscall"; DO NOT EDIT.
package socket
import (
"syscall"
"unsafe"
"golang.org/x/sys/windows"
)
var _ unsafe.Pointer
// Do the interface allocations only once for common
// Errno values.
const (
errnoERROR_IO_PENDING = 997
)
var (
errERROR_IO_PENDING error = syscall.Errno(errnoERROR_IO_PENDING)
errERROR_EINVAL error = syscall.EINVAL
)
// errnoErr returns common boxed Errno values, to prevent
// allocations at runtime.
func errnoErr(e syscall.Errno) error {
switch e {
case 0:
return errERROR_EINVAL
case errnoERROR_IO_PENDING:
return errERROR_IO_PENDING
}
return e
}
var (
modws2_32 = windows.NewLazySystemDLL("ws2_32.dll")
procbind = modws2_32.NewProc("bind")
procgetpeername = modws2_32.NewProc("getpeername")
procgetsockname = modws2_32.NewProc("getsockname")
)
func bind(s windows.Handle, name unsafe.Pointer, namelen int32) (err error) {
r1, _, e1 := syscall.SyscallN(procbind.Addr(), uintptr(s), uintptr(name), uintptr(namelen))
if r1 == socketError {
err = errnoErr(e1)
}
return
}
func getpeername(s windows.Handle, name unsafe.Pointer, namelen *int32) (err error) {
r1, _, e1 := syscall.SyscallN(procgetpeername.Addr(), uintptr(s), uintptr(name), uintptr(unsafe.Pointer(namelen)))
if r1 == socketError {
err = errnoErr(e1)
}
return
}
func getsockname(s windows.Handle, name unsafe.Pointer, namelen *int32) (err error) {
r1, _, e1 := syscall.SyscallN(procgetsockname.Addr(), uintptr(s), uintptr(name), uintptr(unsafe.Pointer(namelen)))
if r1 == socketError {
err = errnoErr(e1)
}
return
}

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package stringbuffer
import (
"sync"
"unicode/utf16"
)
// TODO: worth exporting and using in mkwinsyscall?
// Uint16BufferSize is the buffer size in the pool, chosen somewhat arbitrarily to accommodate
// large path strings:
// MAX_PATH (260) + size of volume GUID prefix (49) + null terminator = 310.
const MinWStringCap = 310
// use *[]uint16 since []uint16 creates an extra allocation where the slice header
// is copied to heap and then referenced via pointer in the interface header that sync.Pool
// stores.
var pathPool = sync.Pool{ // if go1.18+ adds Pool[T], use that to store []uint16 directly
New: func() interface{} {
b := make([]uint16, MinWStringCap)
return &b
},
}
func newBuffer() []uint16 { return *(pathPool.Get().(*[]uint16)) }
// freeBuffer copies the slice header data, and puts a pointer to that in the pool.
// This avoids taking a pointer to the slice header in WString, which can be set to nil.
func freeBuffer(b []uint16) { pathPool.Put(&b) }
// WString is a wide string buffer ([]uint16) meant for storing UTF-16 encoded strings
// for interacting with Win32 APIs.
// Sizes are specified as uint32 and not int.
//
// It is not thread safe.
type WString struct {
// type-def allows casting to []uint16 directly, use struct to prevent that and allow adding fields in the future.
// raw buffer
b []uint16
}
// NewWString returns a [WString] allocated from a shared pool with an
// initial capacity of at least [MinWStringCap].
// Since the buffer may have been previously used, its contents are not guaranteed to be empty.
//
// The buffer should be freed via [WString.Free]
func NewWString() *WString {
return &WString{
b: newBuffer(),
}
}
func (b *WString) Free() {
if b.empty() {
return
}
freeBuffer(b.b)
b.b = nil
}
// ResizeTo grows the buffer to at least c and returns the new capacity, freeing the
// previous buffer back into pool.
func (b *WString) ResizeTo(c uint32) uint32 {
// already sufficient (or n is 0)
if c <= b.Cap() {
return b.Cap()
}
if c <= MinWStringCap {
c = MinWStringCap
}
// allocate at-least double buffer size, as is done in [bytes.Buffer] and other places
if c <= 2*b.Cap() {
c = 2 * b.Cap()
}
b2 := make([]uint16, c)
if !b.empty() {
copy(b2, b.b)
freeBuffer(b.b)
}
b.b = b2
return c
}
// Buffer returns the underlying []uint16 buffer.
func (b *WString) Buffer() []uint16 {
if b.empty() {
return nil
}
return b.b
}
// Pointer returns a pointer to the first uint16 in the buffer.
// If the [WString.Free] has already been called, the pointer will be nil.
func (b *WString) Pointer() *uint16 {
if b.empty() {
return nil
}
return &b.b[0]
}
// String returns the returns the UTF-8 encoding of the UTF-16 string in the buffer.
//
// It assumes that the data is null-terminated.
func (b *WString) String() string {
// Using [windows.UTF16ToString] would require importing "golang.org/x/sys/windows"
// and would make this code Windows-only, which makes no sense.
// So copy UTF16ToString code into here.
// If other windows-specific code is added, switch to [windows.UTF16ToString]
s := b.b
for i, v := range s {
if v == 0 {
s = s[:i]
break
}
}
return string(utf16.Decode(s))
}
// Cap returns the underlying buffer capacity.
func (b *WString) Cap() uint32 {
if b.empty() {
return 0
}
return b.cap()
}
func (b *WString) cap() uint32 { return uint32(cap(b.b)) }
func (b *WString) empty() bool { return b == nil || b.cap() == 0 }