| 1 | /* |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This source code is licensed under both the BSD-style license (found in the |
| 6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| 7 | * in the COPYING file in the root directory of this source tree). |
| 8 | */ |
| 9 | #pragma once |
| 10 | |
| 11 | #include <atomic> |
| 12 | #include <cassert> |
| 13 | #include <stdexcept> |
| 14 | #include <string> |
| 15 | |
| 16 | namespace pzstd { |
| 17 | |
| 18 | // Coordinates graceful shutdown of the pzstd pipeline |
| 19 | class ErrorHolder { |
| 20 | std::atomic<bool> error_; |
| 21 | std::string message_; |
| 22 | |
| 23 | public: |
| 24 | ErrorHolder() : error_(false) {} |
| 25 | |
| 26 | bool hasError() noexcept { |
| 27 | return error_.load(); |
| 28 | } |
| 29 | |
| 30 | void setError(std::string message) noexcept { |
| 31 | // Given multiple possibly concurrent calls, exactly one will ever succeed. |
| 32 | bool expected = false; |
| 33 | if (error_.compare_exchange_strong(expected, true)) { |
| 34 | message_ = std::move(message); |
| 35 | } |
| 36 | } |
| 37 | |
| 38 | bool check(bool predicate, std::string message) noexcept { |
| 39 | if (!predicate) { |
| 40 | setError(std::move(message)); |
| 41 | } |
| 42 | return !hasError(); |
| 43 | } |
| 44 | |
| 45 | std::string getError() noexcept { |
| 46 | error_.store(false); |
| 47 | return std::move(message_); |
| 48 | } |
| 49 | |
| 50 | ~ErrorHolder() { |
| 51 | assert(!hasError()); |
| 52 | } |
| 53 | }; |
| 54 | } |