1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #pragma once 17 18 #include <stdio.h> 19 #include <stdarg.h> 20 21 #include <string> 22 23 class Result { 24 public: success()25 static Result success() { 26 return Result(true); 27 } 28 // Construct a result indicating an error. error(std::string message)29 static Result error(std::string message) { 30 return Result(message); 31 } error(const char * format,...)32 static Result error(const char* format, ...) { 33 char buffer[1024]; 34 va_list args; 35 va_start(args, format); 36 vsnprintf(buffer, sizeof(buffer), format, args); 37 va_end(args); 38 buffer[sizeof(buffer) - 1] = '\0'; 39 return Result(std::string(buffer)); 40 } 41 isSuccess()42 bool isSuccess() const { return mSuccess; } 43 bool operator!() const { return !mSuccess; } 44 c_str()45 const char* c_str() const { return mMessage.c_str(); } 46 private: Result(bool success)47 explicit Result(bool success) : mSuccess(success) { } Result(std::string message)48 explicit Result(std::string message) 49 : mMessage(message), mSuccess(false) { 50 } 51 std::string mMessage; 52 bool mSuccess; 53 }; 54 55