| // Copyright 2018 The Dawn Authors |
| // |
| // 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. |
| |
| #ifndef DAWNNATIVE_ERROR_H_ |
| #define DAWNNATIVE_ERROR_H_ |
| |
| #include "common/Result.h" |
| |
| namespace dawn_native { |
| |
| // This is the content of an error value for MaybeError or ResultOrError, split off to its own |
| // file to avoid having all files including headers like <string> and <vector> |
| class ErrorData; |
| |
| enum class ErrorType : uint32_t { Validation, ContextLost, Unimplemented }; |
| |
| // MaybeError and ResultOrError are meant to be used as return value for function that are not |
| // expected to, but might fail. The handling of error is potentially much slower than successes. |
| using MaybeError = Result<void, ErrorData*>; |
| |
| template <typename T> |
| using ResultOrError = Result<T, ErrorData*>; |
| |
| // Returning a success is done like so: |
| // return {}; // for Error |
| // return SomethingOfTypeT; // for ResultOrError<T> |
| // |
| // Returning an error is done via: |
| // return DAWN_MAKE_ERROR(errorType, "My error message"); |
| // |
| // but shorthand version for specific error types are preferred: |
| // return DAWN_VALIDATION_ERROR("My error message"); |
| #define DAWN_MAKE_ERROR(TYPE, MESSAGE) MakeError(TYPE, MESSAGE, __FILE__, __func__, __LINE__) |
| #define DAWN_VALIDATION_ERROR(MESSAGE) DAWN_MAKE_ERROR(ErrorType::Validation, MESSAGE) |
| #define DAWN_CONTEXT_LOST_ERROR(MESSAGE) DAWN_MAKE_ERROR(ErrorType::ContextLost, MESSAGE) |
| #define DAWN_UNIMPLEMENTED_ERROR(MESSAGE) DAWN_MAKE_ERROR(ErrorType::Unimplemented, MESSAGE) |
| |
| #define DAWN_CONCAT1(x, y) x##y |
| #define DAWN_CONCAT2(x, y) DAWN_CONCAT1(x, y) |
| #define DAWN_LOCAL_VAR DAWN_CONCAT2(_localVar, __LINE__) |
| |
| // When Errors aren't handled explicitly, calls to functions returning errors should be |
| // wrapped in an DAWN_TRY. It will return the error if any, otherwise keep executing |
| // the current function. |
| #define DAWN_TRY(EXPR) \ |
| { \ |
| auto DAWN_LOCAL_VAR = EXPR; \ |
| if (DAWN_UNLIKELY(DAWN_LOCAL_VAR.IsError())) { \ |
| ErrorData* error = DAWN_LOCAL_VAR.AcquireError(); \ |
| AppendBacktrace(error, __FILE__, __func__, __LINE__); \ |
| return {error}; \ |
| } \ |
| } \ |
| for (;;) \ |
| break |
| |
| // DAWN_TRY_ASSIGN is the same as DAWN_TRY for ResultOrError and assigns the success value, if |
| // any, to VAR. |
| #define DAWN_TRY_ASSIGN(VAR, EXPR) \ |
| { \ |
| auto DAWN_LOCAL_VAR = EXPR; \ |
| if (DAWN_UNLIKELY(DAWN_LOCAL_VAR.IsError())) { \ |
| ErrorData* error = DAWN_LOCAL_VAR.AcquireError(); \ |
| AppendBacktrace(error, __FILE__, __func__, __LINE__); \ |
| return {error}; \ |
| } \ |
| VAR = DAWN_LOCAL_VAR.AcquireSuccess(); \ |
| } \ |
| for (;;) \ |
| break |
| |
| // Implementation detail of DAWN_TRY and DAWN_TRY_ASSIGN's adding to the Error's backtrace. |
| void AppendBacktrace(ErrorData* error, const char* file, const char* function, int line); |
| |
| // Implementation detail of DAWN_MAKE_ERROR |
| ErrorData* MakeError(ErrorType type, |
| const char* message, |
| const char* file, |
| const char* function, |
| int line); |
| |
| } // namespace dawn_native |
| |
| #endif // DAWNNATIVE_ERROR_H_ |