/* * Copyright (c) 2015 PLUMgrid, Inc. * * 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. */ #pragma once #include #include namespace ebpf { class StatusTuple { public: enum class Code { // Not an error, indicates success. OK = 0, // For any error that is not covered in the existing codes. UNKNOWN, INVALID_ARGUMENT, PERMISSION_DENIED, // For any error that was raised when making syscalls. SYSTEM, }; static StatusTuple OK() { return StatusTuple(Code::OK, ""); } StatusTuple(int ret) : ret_(ret) {} StatusTuple(int ret, const char *msg) : ret_(ret), msg_(msg) {} StatusTuple(int ret, const std::string &msg) : ret_(ret), msg_(msg) {} template StatusTuple(int ret, const char *fmt, Args... args) : ret_(ret) { char buf[2048]; snprintf(buf, sizeof(buf), fmt, args...); msg_ = std::string(buf); } StatusTuple(Code code, const std::string &msg) : use_enum_code_(true), code_(code), msg_(msg) {} void append_msg(const std::string& msg) { msg_ += msg; } bool ok() const { if (use_enum_code_) { return code_ == Code::OK; } return ret_ == 0; } int code() const { if (use_enum_code_) { return static_cast(code_); } return ret_; } const std::string& msg() const { return msg_; } private: int ret_; bool use_enum_code_ = false; Code code_ = Code::UNKNOWN; std::string msg_; }; #define TRY2(CMD) \ do { \ ebpf::StatusTuple __stp = (CMD); \ if (__stp.code() != 0) { \ return __stp; \ } \ } while (0) namespace error { #define DECLARE_ERROR(FN, CODE) \ inline StatusTuple FN(const std::string& msg) { \ return StatusTuple(::ebpf::StatusTuple::Code::CODE, msg); \ } \ inline bool Is##FN(const StatusTuple& status) { \ return status.code() == static_cast(::ebpf::StatusTuple::Code::CODE); \ } DECLARE_ERROR(Unknown, UNKNOWN) DECLARE_ERROR(InvalidArgument, INVALID_ARGUMENT) DECLARE_ERROR(PermissionDenied, PERMISSION_DENIED) DECLARE_ERROR(System, SYSTEM) } // namespace error } // namespace ebpf