mirror of
https://codeberg.org/superseriousbusiness/gotosocial.git
synced 2024-12-18 15:11:47 +03:00
342 lines
7.5 KiB
Go
342 lines
7.5 KiB
Go
package mangler
|
|
|
|
import (
|
|
"encoding"
|
|
"net/url"
|
|
"reflect"
|
|
"time"
|
|
)
|
|
|
|
// loadMangler is the top-most Mangler load function. It guarantees that a Mangler
|
|
// function will be returned for given value interface{} and reflected type. Else panics.
|
|
func loadMangler(a any, t reflect.Type) Mangler {
|
|
// Load mangler function
|
|
mng, rmng := load(a, t)
|
|
|
|
if rmng != nil {
|
|
// Wrap reflect mangler to handle iface
|
|
return func(buf []byte, a any) []byte {
|
|
return rmng(buf, reflect.ValueOf(a))
|
|
}
|
|
}
|
|
|
|
if mng == nil {
|
|
// No mangler function could be determined
|
|
panic("cannot mangle type: " + t.String())
|
|
}
|
|
|
|
return mng
|
|
}
|
|
|
|
// load will load a Mangler or reflect Mangler for given type and iface 'a'.
|
|
// Note: allocates new interface value if nil provided, i.e. if coming via reflection.
|
|
func load(a any, t reflect.Type) (Mangler, rMangler) {
|
|
if t == nil {
|
|
// There is no reflect type to search by
|
|
panic("cannot mangle nil interface{} type")
|
|
}
|
|
|
|
if a == nil {
|
|
// Alloc new iface instance
|
|
v := reflect.New(t).Elem()
|
|
a = v.Interface()
|
|
}
|
|
|
|
// Check in fast iface type switch
|
|
if mng := loadIface(a); mng != nil {
|
|
return mng, nil
|
|
}
|
|
|
|
// Search by reflection
|
|
return loadReflect(t)
|
|
}
|
|
|
|
// loadIface is used as a first-resort interface{} type switcher loader
|
|
// for types implementing Mangled and providing performant alternative
|
|
// Mangler functions for standard library types to avoid reflection.
|
|
func loadIface(a any) Mangler {
|
|
switch a.(type) {
|
|
case Mangled:
|
|
return mangle_mangled
|
|
|
|
case time.Time:
|
|
return mangle_time
|
|
|
|
case *time.Time:
|
|
return mangle_time_ptr
|
|
|
|
case *url.URL:
|
|
return mangle_stringer
|
|
|
|
case encoding.BinaryMarshaler:
|
|
return mangle_binary
|
|
|
|
// NOTE:
|
|
// we don't just handle ALL fmt.Stringer types as often
|
|
// the output is large and unwieldy and this interface
|
|
// switch is for types it would be faster to avoid reflection.
|
|
// If they want better performance they can implement Mangled{}.
|
|
|
|
default:
|
|
return nil
|
|
}
|
|
}
|
|
|
|
// loadReflect will load a Mangler (or rMangler) function for the given reflected type info.
|
|
// NOTE: this is used as the top level load function for nested reflective searches.
|
|
func loadReflect(t reflect.Type) (Mangler, rMangler) {
|
|
switch t.Kind() {
|
|
case reflect.Pointer:
|
|
return loadReflectPtr(t.Elem())
|
|
|
|
case reflect.String:
|
|
return mangle_string, nil
|
|
|
|
case reflect.Array:
|
|
return nil, loadReflectArray(t.Elem())
|
|
|
|
case reflect.Slice:
|
|
// Element type
|
|
et := t.Elem()
|
|
|
|
// Preferably look for known slice mangler func
|
|
if mng := loadReflectKnownSlice(et); mng != nil {
|
|
return mng, nil
|
|
}
|
|
|
|
// Else handle as array elements
|
|
return nil, loadReflectArray(et)
|
|
|
|
case reflect.Map:
|
|
return nil, loadReflectMap(t.Key(), t.Elem())
|
|
|
|
case reflect.Bool:
|
|
return mangle_bool, nil
|
|
|
|
case reflect.Int,
|
|
reflect.Uint,
|
|
reflect.Uintptr:
|
|
return mangle_platform_int, nil
|
|
|
|
case reflect.Int8, reflect.Uint8:
|
|
return mangle_8bit, nil
|
|
|
|
case reflect.Int16, reflect.Uint16:
|
|
return mangle_16bit, nil
|
|
|
|
case reflect.Int32, reflect.Uint32:
|
|
return mangle_32bit, nil
|
|
|
|
case reflect.Int64, reflect.Uint64:
|
|
return mangle_64bit, nil
|
|
|
|
case reflect.Float32:
|
|
return mangle_32bit, nil
|
|
|
|
case reflect.Float64:
|
|
return mangle_64bit, nil
|
|
|
|
case reflect.Complex64:
|
|
return mangle_64bit, nil
|
|
|
|
case reflect.Complex128:
|
|
return mangle_128bit, nil
|
|
|
|
default:
|
|
return nil, nil
|
|
}
|
|
}
|
|
|
|
// loadReflectPtr loads a Mangler (or rMangler) function for a ptr's element type.
|
|
// This also handles further dereferencing of any further ptr indrections (e.g. ***int).
|
|
func loadReflectPtr(et reflect.Type) (Mangler, rMangler) {
|
|
count := 1
|
|
|
|
// Iteratively dereference ptrs
|
|
for et.Kind() == reflect.Pointer {
|
|
et = et.Elem()
|
|
count++
|
|
}
|
|
|
|
if et.Kind() == reflect.Array {
|
|
// Special case of addressable (sliceable) array
|
|
if mng := loadReflectKnownSlice(et); mng != nil {
|
|
if count == 1 {
|
|
return mng, nil
|
|
}
|
|
return nil, deref_ptr_mangler(mng, count-1)
|
|
}
|
|
|
|
// Look for an array mangler function, this will
|
|
// access elements by index using reflect.Value and
|
|
// pass each one to a separate mangler function.
|
|
if rmng := loadReflectArray(et); rmng != nil {
|
|
return nil, deref_ptr_rmangler(rmng, count)
|
|
}
|
|
|
|
return nil, nil
|
|
}
|
|
|
|
// Try remove a layer of derefs by loading a mangler
|
|
// for a known ptr kind. The less reflection the better!
|
|
if mng := loadReflectKnownPtr(et); mng != nil {
|
|
if count == 1 {
|
|
return mng, nil
|
|
}
|
|
return nil, deref_ptr_mangler(mng, count-1)
|
|
}
|
|
|
|
// Search for ptr elemn type mangler
|
|
if mng, rmng := load(nil, et); mng != nil {
|
|
return nil, deref_ptr_mangler(mng, count)
|
|
} else if rmng != nil {
|
|
return nil, deref_ptr_rmangler(rmng, count)
|
|
}
|
|
|
|
return nil, nil
|
|
}
|
|
|
|
// loadReflectKnownPtr loads a Mangler function for a known ptr-of-element type (in this case, primtive ptrs).
|
|
func loadReflectKnownPtr(et reflect.Type) Mangler {
|
|
switch et.Kind() {
|
|
case reflect.String:
|
|
return mangle_string_ptr
|
|
|
|
case reflect.Bool:
|
|
return mangle_bool_ptr
|
|
|
|
case reflect.Int,
|
|
reflect.Uint,
|
|
reflect.Uintptr:
|
|
return mangle_platform_int_ptr
|
|
|
|
case reflect.Int8, reflect.Uint8:
|
|
return mangle_8bit_ptr
|
|
|
|
case reflect.Int16, reflect.Uint16:
|
|
return mangle_16bit_ptr
|
|
|
|
case reflect.Int32, reflect.Uint32:
|
|
return mangle_32bit_ptr
|
|
|
|
case reflect.Int64, reflect.Uint64:
|
|
return mangle_64bit_ptr
|
|
|
|
case reflect.Float32:
|
|
return mangle_32bit_ptr
|
|
|
|
case reflect.Float64:
|
|
return mangle_64bit_ptr
|
|
|
|
case reflect.Complex64:
|
|
return mangle_64bit_ptr
|
|
|
|
case reflect.Complex128:
|
|
return mangle_128bit_ptr
|
|
|
|
default:
|
|
return nil
|
|
}
|
|
}
|
|
|
|
// loadReflectKnownSlice loads a Mangler function for a known slice-of-element type (in this case, primtives).
|
|
func loadReflectKnownSlice(et reflect.Type) Mangler {
|
|
switch et.Kind() {
|
|
case reflect.String:
|
|
return mangle_string_slice
|
|
|
|
case reflect.Bool:
|
|
return mangle_bool_slice
|
|
|
|
case reflect.Int,
|
|
reflect.Uint,
|
|
reflect.Uintptr:
|
|
return mangle_platform_int_slice
|
|
|
|
case reflect.Int8, reflect.Uint8:
|
|
return mangle_8bit_slice
|
|
|
|
case reflect.Int16, reflect.Uint16:
|
|
return mangle_16bit_slice
|
|
|
|
case reflect.Int32, reflect.Uint32:
|
|
return mangle_32bit_slice
|
|
|
|
case reflect.Int64, reflect.Uint64:
|
|
return mangle_64bit_slice
|
|
|
|
case reflect.Float32:
|
|
return mangle_32bit_slice
|
|
|
|
case reflect.Float64:
|
|
return mangle_64bit_slice
|
|
|
|
case reflect.Complex64:
|
|
return mangle_64bit_slice
|
|
|
|
case reflect.Complex128:
|
|
return mangle_128bit_slice
|
|
|
|
default:
|
|
return nil
|
|
}
|
|
}
|
|
|
|
// loadReflectArray loads an rMangler function for an array (or slice) or given element type.
|
|
func loadReflectArray(et reflect.Type) rMangler {
|
|
// Search via reflected array element type
|
|
if mng, rmng := load(nil, et); mng != nil {
|
|
return iter_array_mangler(mng)
|
|
} else if rmng != nil {
|
|
return iter_array_rmangler(rmng)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// loadReflectMap loads an rMangler function for a map of given key and value types.
|
|
func loadReflectMap(kt, vt reflect.Type) rMangler {
|
|
var kmng, vmng rMangler
|
|
|
|
// Search for mangler for key type
|
|
mng, rmng := load(nil, kt)
|
|
|
|
switch {
|
|
// Wrap key mangler to reflect
|
|
case mng != nil:
|
|
mng := mng // take our own ptr
|
|
kmng = func(buf []byte, v reflect.Value) []byte {
|
|
return mng(buf, v.Interface())
|
|
}
|
|
|
|
// Use reflect key mangler as-is
|
|
case rmng != nil:
|
|
kmng = rmng
|
|
|
|
// No mangler found
|
|
default:
|
|
return nil
|
|
}
|
|
|
|
// Search for mangler for value type
|
|
mng, rmng = load(nil, vt)
|
|
|
|
switch {
|
|
// Wrap key mangler to reflect
|
|
case mng != nil:
|
|
mng := mng // take our own ptr
|
|
vmng = func(buf []byte, v reflect.Value) []byte {
|
|
return mng(buf, v.Interface())
|
|
}
|
|
|
|
// Use reflect key mangler as-is
|
|
case rmng != nil:
|
|
vmng = rmng
|
|
|
|
// No mangler found
|
|
default:
|
|
return nil
|
|
}
|
|
|
|
// Wrap key/value manglers in map iter
|
|
return iter_map_rmangler(kmng, vmng)
|
|
}
|