1 | /* |
2 | * Copyright 2015-present Facebook, Inc. |
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 | #pragma once |
18 | |
19 | #include <boost/program_options.hpp> |
20 | |
21 | #include <folly/Optional.h> |
22 | #include <folly/portability/GFlags.h> |
23 | |
24 | namespace folly { |
25 | |
26 | enum class ProgramOptionsStyle { |
27 | GFLAGS, |
28 | GNU, |
29 | }; |
30 | |
31 | // Add all GFlags to the given options_description. |
32 | // Use this *instead of* gflags::ParseCommandLineFlags(). |
33 | // |
34 | // in GFLAGS style, the flags are named as per gflags conventions: |
35 | // names_with_underscores |
36 | // boolean flags have a "no" prefix |
37 | // |
38 | // in GNU style, the flags are named as per GNU conventions: |
39 | // names-with-dashes |
40 | // boolean flags have a "no-" prefix |
41 | // |
42 | // Consider (for example) a boolean flag: |
43 | // DEFINE_bool(flying_pigs, false, "..."); |
44 | // |
45 | // In GFLAGS style, the corresponding flags are named |
46 | // flying_pigs |
47 | // noflying_pigs |
48 | // |
49 | // In GNU style, the corresponding flags are named |
50 | // flying-pigs |
51 | // no-flying-pigs |
52 | // |
53 | // You may not pass arguments to boolean flags, so you must use the |
54 | // "no" / "no-" prefix to set them to false; "--flying_pigs false" |
55 | // and "--flying_pigs=false" are not allowed, to prevent ambiguity. |
56 | boost::program_options::options_description getGFlags( |
57 | ProgramOptionsStyle style = ProgramOptionsStyle::GNU); |
58 | |
59 | // Helper when parsing nested command lines: |
60 | // |
61 | // program [--common_options...] command [--command_options...] args |
62 | // |
63 | // The result has "command" set to the first positional argument, if any, |
64 | // and "rest" set to the remaining options and arguments. Note that any |
65 | // unrecognized flags must appear after the command name. |
66 | // |
67 | // You may pass "rest" to parseNestedCommandLine again, etc. |
68 | struct NestedCommandLineParseResult { |
69 | NestedCommandLineParseResult() {} |
70 | |
71 | boost::program_options::parsed_options options{nullptr}; |
72 | |
73 | Optional<std::string> command; |
74 | std::vector<std::string> rest; |
75 | }; |
76 | |
77 | NestedCommandLineParseResult parseNestedCommandLine( |
78 | int argc, |
79 | const char* const argv[], |
80 | const boost::program_options::options_description& desc); |
81 | |
82 | NestedCommandLineParseResult parseNestedCommandLine( |
83 | const std::vector<std::string>& cmdline, |
84 | const boost::program_options::options_description& desc); |
85 | |
86 | } // namespace folly |
87 | |