build: move e2e dependencies into e2e/go.mod

Several packages are only used while running the e2e suite. These
packages are less important to update, as the they can not influence the
final executable that is part of the Ceph-CSI container-image.

By moving these dependencies out of the main Ceph-CSI go.mod, it is
easier to identify if a reported CVE affects Ceph-CSI, or only the
testing (like most of the Kubernetes CVEs).

Signed-off-by: Niels de Vos <ndevos@ibm.com>
This commit is contained in:
Niels de Vos
2025-03-04 08:57:28 +01:00
committed by mergify[bot]
parent 15da101b1b
commit bec6090996
8047 changed files with 1407827 additions and 3453 deletions

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// This package contains Win32 filesystem functionality.
package fs

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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 }