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Diffstat (limited to 'vendor/k8s.io/apimachinery/pkg/conversion/cloner.go')
-rw-r--r--vendor/k8s.io/apimachinery/pkg/conversion/cloner.go249
1 files changed, 249 insertions, 0 deletions
diff --git a/vendor/k8s.io/apimachinery/pkg/conversion/cloner.go b/vendor/k8s.io/apimachinery/pkg/conversion/cloner.go
new file mode 100644
index 000000000..c5dec1f31
--- /dev/null
+++ b/vendor/k8s.io/apimachinery/pkg/conversion/cloner.go
@@ -0,0 +1,249 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package conversion
+
+import (
+ "fmt"
+ "reflect"
+)
+
+// Cloner knows how to copy one type to another.
+type Cloner struct {
+ // Map from the type to a function which can do the deep copy.
+ deepCopyFuncs map[reflect.Type]reflect.Value
+ generatedDeepCopyFuncs map[reflect.Type]func(in interface{}, out interface{}, c *Cloner) error
+}
+
+// NewCloner creates a new Cloner object.
+func NewCloner() *Cloner {
+ c := &Cloner{
+ deepCopyFuncs: map[reflect.Type]reflect.Value{},
+ generatedDeepCopyFuncs: map[reflect.Type]func(in interface{}, out interface{}, c *Cloner) error{},
+ }
+ if err := c.RegisterDeepCopyFunc(byteSliceDeepCopy); err != nil {
+ // If one of the deep-copy functions is malformed, detect it immediately.
+ panic(err)
+ }
+ return c
+}
+
+// Prevent recursing into every byte...
+func byteSliceDeepCopy(in *[]byte, out *[]byte, c *Cloner) error {
+ if *in != nil {
+ *out = make([]byte, len(*in))
+ copy(*out, *in)
+ } else {
+ *out = nil
+ }
+ return nil
+}
+
+// Verifies whether a deep-copy function has a correct signature.
+func verifyDeepCopyFunctionSignature(ft reflect.Type) error {
+ if ft.Kind() != reflect.Func {
+ return fmt.Errorf("expected func, got: %v", ft)
+ }
+ if ft.NumIn() != 3 {
+ return fmt.Errorf("expected three 'in' params, got %v", ft)
+ }
+ if ft.NumOut() != 1 {
+ return fmt.Errorf("expected one 'out' param, got %v", ft)
+ }
+ if ft.In(0).Kind() != reflect.Ptr {
+ return fmt.Errorf("expected pointer arg for 'in' param 0, got: %v", ft)
+ }
+ if ft.In(1) != ft.In(0) {
+ return fmt.Errorf("expected 'in' param 0 the same as param 1, got: %v", ft)
+ }
+ var forClonerType Cloner
+ if expected := reflect.TypeOf(&forClonerType); ft.In(2) != expected {
+ return fmt.Errorf("expected '%v' arg for 'in' param 2, got: '%v'", expected, ft.In(2))
+ }
+ var forErrorType error
+ // This convolution is necessary, otherwise TypeOf picks up on the fact
+ // that forErrorType is nil
+ errorType := reflect.TypeOf(&forErrorType).Elem()
+ if ft.Out(0) != errorType {
+ return fmt.Errorf("expected error return, got: %v", ft)
+ }
+ return nil
+}
+
+// RegisterGeneratedDeepCopyFunc registers a copying func with the Cloner.
+// deepCopyFunc must take three parameters: a type input, a pointer to a
+// type output, and a pointer to Cloner. It should return an error.
+//
+// Example:
+// c.RegisterGeneratedDeepCopyFunc(
+// func(in Pod, out *Pod, c *Cloner) error {
+// // deep copy logic...
+// return nil
+// })
+func (c *Cloner) RegisterDeepCopyFunc(deepCopyFunc interface{}) error {
+ fv := reflect.ValueOf(deepCopyFunc)
+ ft := fv.Type()
+ if err := verifyDeepCopyFunctionSignature(ft); err != nil {
+ return err
+ }
+ c.deepCopyFuncs[ft.In(0)] = fv
+ return nil
+}
+
+// GeneratedDeepCopyFunc bundles an untyped generated deep-copy function of a type
+// with a reflection type object used as a key to lookup the deep-copy function.
+type GeneratedDeepCopyFunc struct {
+ Fn func(in interface{}, out interface{}, c *Cloner) error
+ InType reflect.Type
+}
+
+// Similar to RegisterDeepCopyFunc, but registers deep copy function that were
+// automatically generated.
+func (c *Cloner) RegisterGeneratedDeepCopyFunc(fn GeneratedDeepCopyFunc) error {
+ c.generatedDeepCopyFuncs[fn.InType] = fn.Fn
+ return nil
+}
+
+// DeepCopy will perform a deep copy of a given object.
+func (c *Cloner) DeepCopy(in interface{}) (interface{}, error) {
+ // Can be invalid if we run DeepCopy(X) where X is a nil interface type.
+ // For example, we get an invalid value when someone tries to deep-copy
+ // a nil labels.Selector.
+ // This does not occur if X is nil and is a pointer to a concrete type.
+ if in == nil {
+ return nil, nil
+ }
+ inValue := reflect.ValueOf(in)
+ outValue, err := c.deepCopy(inValue)
+ if err != nil {
+ return nil, err
+ }
+ return outValue.Interface(), nil
+}
+
+func (c *Cloner) deepCopy(src reflect.Value) (reflect.Value, error) {
+ inType := src.Type()
+
+ switch src.Kind() {
+ case reflect.Interface, reflect.Ptr, reflect.Map, reflect.Slice:
+ if src.IsNil() {
+ return src, nil
+ }
+ }
+
+ if fv, ok := c.deepCopyFuncs[inType]; ok {
+ return c.customDeepCopy(src, fv)
+ }
+ if fv, ok := c.generatedDeepCopyFuncs[inType]; ok {
+ var outValue reflect.Value
+ outValue = reflect.New(inType.Elem())
+ err := fv(src.Interface(), outValue.Interface(), c)
+ return outValue, err
+ }
+ return c.defaultDeepCopy(src)
+}
+
+func (c *Cloner) customDeepCopy(src, fv reflect.Value) (reflect.Value, error) {
+ outValue := reflect.New(src.Type().Elem())
+ args := []reflect.Value{src, outValue, reflect.ValueOf(c)}
+ result := fv.Call(args)[0].Interface()
+ // This convolution is necessary because nil interfaces won't convert
+ // to error.
+ if result == nil {
+ return outValue, nil
+ }
+ return outValue, result.(error)
+}
+
+func (c *Cloner) defaultDeepCopy(src reflect.Value) (reflect.Value, error) {
+ switch src.Kind() {
+ case reflect.Chan, reflect.Func, reflect.UnsafePointer, reflect.Uintptr:
+ return src, fmt.Errorf("cannot deep copy kind: %s", src.Kind())
+ case reflect.Array:
+ dst := reflect.New(src.Type())
+ for i := 0; i < src.Len(); i++ {
+ copyVal, err := c.deepCopy(src.Index(i))
+ if err != nil {
+ return src, err
+ }
+ dst.Elem().Index(i).Set(copyVal)
+ }
+ return dst.Elem(), nil
+ case reflect.Interface:
+ if src.IsNil() {
+ return src, nil
+ }
+ return c.deepCopy(src.Elem())
+ case reflect.Map:
+ if src.IsNil() {
+ return src, nil
+ }
+ dst := reflect.MakeMap(src.Type())
+ for _, k := range src.MapKeys() {
+ copyVal, err := c.deepCopy(src.MapIndex(k))
+ if err != nil {
+ return src, err
+ }
+ dst.SetMapIndex(k, copyVal)
+ }
+ return dst, nil
+ case reflect.Ptr:
+ if src.IsNil() {
+ return src, nil
+ }
+ dst := reflect.New(src.Type().Elem())
+ copyVal, err := c.deepCopy(src.Elem())
+ if err != nil {
+ return src, err
+ }
+ dst.Elem().Set(copyVal)
+ return dst, nil
+ case reflect.Slice:
+ if src.IsNil() {
+ return src, nil
+ }
+ dst := reflect.MakeSlice(src.Type(), 0, src.Len())
+ for i := 0; i < src.Len(); i++ {
+ copyVal, err := c.deepCopy(src.Index(i))
+ if err != nil {
+ return src, err
+ }
+ dst = reflect.Append(dst, copyVal)
+ }
+ return dst, nil
+ case reflect.Struct:
+ dst := reflect.New(src.Type())
+ for i := 0; i < src.NumField(); i++ {
+ if !dst.Elem().Field(i).CanSet() {
+ // Can't set private fields. At this point, the
+ // best we can do is a shallow copy. For
+ // example, time.Time is a value type with
+ // private members that can be shallow copied.
+ return src, nil
+ }
+ copyVal, err := c.deepCopy(src.Field(i))
+ if err != nil {
+ return src, err
+ }
+ dst.Elem().Field(i).Set(copyVal)
+ }
+ return dst.Elem(), nil
+
+ default:
+ // Value types like numbers, booleans, and strings.
+ return src, nil
+ }
+}