1 // Copyright 2024 The Pigweed Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not 4 // use this file except in compliance with the License. You may obtain a copy of 5 // the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12 // License for the specific language governing permissions and limitations under 13 // the License. 14 15 #pragma once 16 17 /// Returns `Poll::Pending()` if \a expr is `Poll::Pending()`. 18 #define PW_TRY_READY(expr) \ 19 do { \ 20 if ((expr).IsPending()) { \ 21 return ::pw::async2::Pending(); \ 22 } \ 23 } while (0) 24 25 #define PW_TRY_READY_ASSIGN(lhs, expression) \ 26 _PW_TRY_READY_ASSIGN(_PW_TRY_READY_UNIQUE(__LINE__), lhs, expression) 27 28 /// Returns `Poll::Pending()` if \a expr is `Poll::Pending()`. If expression 29 /// is `Poll::Ready()`, assigns the inner value to \a lhs. 30 #define _PW_TRY_READY_ASSIGN(result, lhs, expr) \ 31 auto&& result = (expr); \ 32 if (result.IsPending()) { \ 33 return ::pw::async2::Pending(); \ 34 } \ 35 lhs = std::move(*result) 36 37 #define _PW_TRY_READY_UNIQUE(line) _PW_TRY_READY_UNIQUE_EXPANDED(line) 38 #define _PW_TRY_READY_UNIQUE_EXPANDED(line) _pw_try_unique_name_##line 39