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//go:build go1.24 && !go1.26
package xunsafe
import (
"reflect"
"unsafe"
)
func init() {
// TypeOf(reflect.Type{}) == *struct{ abi.Type{} }
t := reflect.TypeOf(reflect.TypeOf(0)).Elem()
if t.Size() != unsafe.Sizeof(Abi_Type{}) {
panic("Abi_Type{} not in sync with abi.Type{}")
}
}
const (
// see: go/src/internal/abi/type.go
Abi_KindDirectIface uint8 = 1 << 5
Abi_KindMask uint8 = (1 << 5) - 1
)
// Abi_Type is a copy of the memory layout of abi.Type{}.
//
// see: go/src/internal/abi/type.go
type Abi_Type struct {
_ uintptr
PtrBytes uintptr
_ uint32
_ uint8
_ uint8
_ uint8
Kind_ uint8
_ func(unsafe.Pointer, unsafe.Pointer) bool
_ *byte
_ int32
_ int32
}
// Abi_EmptyInterface is a copy of the memory layout of abi.EmptyInterface{},
// which is to say also the memory layout of any method-less interface.
//
// see: go/src/internal/abi/iface.go
type Abi_EmptyInterface struct {
Type *Abi_Type
Data unsafe.Pointer
}
// Abi_NonEmptyInterface is a copy of the memory layout of abi.NonEmptyInterface{},
// which is to say also the memory layout of any interface containing method(s).
//
// see: go/src/internal/abi/iface.go on 1.25+
// see: go/src/reflect/value.go on 1.24
type Abi_NonEmptyInterface struct {
ITab uintptr
Data unsafe.Pointer
}
// see: go/src/internal/abi/type.go Type.Kind()
func Abi_Type_Kind(t reflect.Type) uint8 {
iface := (*Abi_NonEmptyInterface)(unsafe.Pointer(&t))
atype := (*Abi_Type)(unsafe.Pointer(iface.Data))
return atype.Kind_ & Abi_KindMask
}
// see: go/src/internal/abi/type.go Type.IfaceIndir()
func Abi_Type_IfaceIndir(t reflect.Type) bool {
iface := (*Abi_NonEmptyInterface)(unsafe.Pointer(&t))
atype := (*Abi_Type)(unsafe.Pointer(iface.Data))
return atype.Kind_&Abi_KindDirectIface == 0
}
// PackIface packs a new reflect.nonEmptyInterface{} using shielded
// itab and data pointer, returning a pointer for caller casting.
func PackIface(itab uintptr, word unsafe.Pointer) unsafe.Pointer {
return unsafe.Pointer(&Abi_NonEmptyInterface{
ITab: itab,
Data: word,
})
}
// GetIfaceITab generates a new value of given type,
// casts it to the generic param interface type, and
// returns the .itab portion of the abi.NonEmptyInterface{}.
// this is useful for later calls to PackIface for known type.
func GetIfaceITab[I any](t reflect.Type) uintptr {
s := reflect.New(t).Elem().Interface().(I)
i := (*Abi_NonEmptyInterface)(unsafe.Pointer(&s))
return i.ITab
}
// UnpackEface returns the .Data portion of an abi.EmptyInterface{}.
func UnpackEface(a any) unsafe.Pointer {
return (*Abi_EmptyInterface)(unsafe.Pointer((&a))).Data
}
// see: go/src/internal/unsafeheader/unsafeheader.go
type Unsafeheader_Slice struct {
Data unsafe.Pointer
Len int
Cap int
}
// see: go/src/internal/unsafeheader/unsafeheader.go
type Unsafeheader_String struct {
Data unsafe.Pointer
Len int
}
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