Igor Murashkin | aaebaa0 | 2015-01-26 10:55:53 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2015 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 | |
| 17 | #ifndef ART_CMDLINE_CMDLINE_TYPE_PARSER_H_ |
| 18 | #define ART_CMDLINE_CMDLINE_TYPE_PARSER_H_ |
| 19 | |
| 20 | #include "cmdline_parse_result.h" |
| 21 | |
| 22 | namespace art { |
| 23 | |
| 24 | // Base class for user-defined CmdlineType<T> specializations. |
| 25 | // |
| 26 | // Not strictly necessary, but if the specializations fail to Define all of these functions |
| 27 | // the compilation will fail. |
| 28 | template <typename T> |
| 29 | struct CmdlineTypeParser { |
| 30 | // Return value of parsing attempts. Represents a Success(T value) or an Error(int code) |
| 31 | using Result = CmdlineParseResult<T>; |
| 32 | |
| 33 | // Parse a single value for an argument definition out of the wildcard component. |
| 34 | // |
| 35 | // e.g. if the argument definition was "foo:_", and the user-provided input was "foo:bar", |
| 36 | // then args is "bar". |
| 37 | Result Parse(const std::string& args ATTRIBUTE_UNUSED) { |
| 38 | assert(false); |
| 39 | return Result::Failure("Missing type specialization and/or value map"); |
| 40 | } |
| 41 | |
| 42 | // Parse a value and append it into the existing value so far, for argument |
| 43 | // definitions which are marked with AppendValues(). |
| 44 | // |
| 45 | // The value is parsed out of the wildcard component as in Parse. |
| 46 | // |
| 47 | // If the initial value does not exist yet, a default value is created by |
| 48 | // value-initializing with 'T()'. |
| 49 | Result ParseAndAppend(const std::string& args ATTRIBUTE_UNUSED, |
| 50 | T& existing_value ATTRIBUTE_UNUSED) { |
| 51 | assert(false); |
| 52 | return Result::Failure("Missing type specialization and/or value map"); |
| 53 | } |
| 54 | |
| 55 | // Runtime type name of T, so that we can print more useful error messages. |
| 56 | static const char* Name() { assert(false); return "UnspecializedType"; } |
| 57 | |
| 58 | // Whether or not your type can parse argument definitions defined without a "_" |
| 59 | // e.g. -Xenable-profiler just mutates the existing profiler struct in-place |
| 60 | // so it doesn't need to do any parsing other than token recognition. |
| 61 | // |
| 62 | // If this is false, then either the argument definition has a _, from which the parsing |
| 63 | // happens, or the tokens get mapped to a value list/map from which a 1:1 matching occurs. |
| 64 | // |
| 65 | // This should almost *always* be false! |
| 66 | static constexpr bool kCanParseBlankless = false; |
| 67 | |
| 68 | protected: |
| 69 | // Don't accidentally initialize instances of this directly; they will assert at runtime. |
| 70 | CmdlineTypeParser() = default; |
| 71 | }; |
| 72 | |
| 73 | |
| 74 | } // namespace art |
| 75 | |
| 76 | #endif // ART_CMDLINE_CMDLINE_TYPE_PARSER_H_ |