| // Licensed to the Apache Software Foundation (ASF) under one or more |
| // contributor license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright ownership. |
| // The ASF licenses this file to You 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 reflectx |
| |
| import ( |
| "fmt" |
| "reflect" |
| "runtime" |
| "unsafe" |
| ) |
| |
| // TODO(herohde) 7/21/2017: we rely on the happy fact that the function name is |
| // also the symbol name. We should perhaps make that connection explicit. |
| |
| // FunctionName returns the symbol name of a function. It panics if the given |
| // value is not a function. |
| func FunctionName(fn interface{}) string { |
| val := reflect.ValueOf(fn) |
| if val.Kind() != reflect.Func { |
| panic(fmt.Sprintf("value %v is not a function", fn)) |
| } |
| |
| return runtime.FuncForPC(uintptr(val.Pointer())).Name() |
| } |
| |
| // LoadFunction loads a function from a pointer and type. Assumes the pointer |
| // points to a valid function implementation. |
| func LoadFunction(ptr uintptr, t reflect.Type) interface{} { |
| v := reflect.New(t).Elem() |
| *(*uintptr)(unsafe.Pointer(v.Addr().Pointer())) = (uintptr)(unsafe.Pointer(&ptr)) |
| return v.Interface() |
| } |
