consul/vendor/github.com/go-ole/go-ole/utility.go

102 lines
2.1 KiB
Go

package ole
import (
"unicode/utf16"
"unsafe"
)
// ClassIDFrom retrieves class ID whether given is program ID or application string.
//
// Helper that provides check against both Class ID from Program ID and Class ID from string. It is
// faster, if you know which you are using, to use the individual functions, but this will check
// against available functions for you.
func ClassIDFrom(programID string) (classID *GUID, err error) {
classID, err = CLSIDFromProgID(programID)
if err != nil {
classID, err = CLSIDFromString(programID)
if err != nil {
return
}
}
return
}
// BytePtrToString converts byte pointer to a Go string.
func BytePtrToString(p *byte) string {
a := (*[10000]uint8)(unsafe.Pointer(p))
i := 0
for a[i] != 0 {
i++
}
return string(a[:i])
}
// UTF16PtrToString is alias for LpOleStrToString.
//
// Kept for compatibility reasons.
func UTF16PtrToString(p *uint16) string {
return LpOleStrToString(p)
}
// LpOleStrToString converts COM Unicode to Go string.
func LpOleStrToString(p *uint16) string {
if p == nil {
return ""
}
length := lpOleStrLen(p)
a := make([]uint16, length)
ptr := unsafe.Pointer(p)
for i := 0; i < int(length); i++ {
a[i] = *(*uint16)(ptr)
ptr = unsafe.Pointer(uintptr(ptr) + 2)
}
return string(utf16.Decode(a))
}
// BstrToString converts COM binary string to Go string.
func BstrToString(p *uint16) string {
if p == nil {
return ""
}
length := SysStringLen((*int16)(unsafe.Pointer(p)))
a := make([]uint16, length)
ptr := unsafe.Pointer(p)
for i := 0; i < int(length); i++ {
a[i] = *(*uint16)(ptr)
ptr = unsafe.Pointer(uintptr(ptr) + 2)
}
return string(utf16.Decode(a))
}
// lpOleStrLen returns the length of Unicode string.
func lpOleStrLen(p *uint16) (length int64) {
if p == nil {
return 0
}
ptr := unsafe.Pointer(p)
for i := 0; ; i++ {
if 0 == *(*uint16)(ptr) {
length = int64(i)
break
}
ptr = unsafe.Pointer(uintptr(ptr) + 2)
}
return
}
// convertHresultToError converts syscall to error, if call is unsuccessful.
func convertHresultToError(hr uintptr, r2 uintptr, ignore error) (err error) {
if hr != 0 {
err = NewError(hr)
}
return
}