git-subtree-dir: third_party/abseil_cpp git-subtree-mainline:ffb2ae54begit-subtree-split:768eb2ca28
		
			
				
	
	
		
			134 lines
		
	
	
	
		
			5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			134 lines
		
	
	
	
		
			5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //
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| //  Copyright 2019 The Abseil Authors.
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| //
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| // Licensed under the Apache License, Version 2.0 (the "License");
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| // you may not use this file except in compliance with the License.
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| // You may obtain a copy of the License at
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| //
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| //      https://www.apache.org/licenses/LICENSE-2.0
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| //
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| // Unless required by applicable law or agreed to in writing, software
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| // distributed under the License is distributed on an "AS IS" BASIS,
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| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| // See the License for the specific language governing permissions and
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| // limitations under the License.
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| //
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| // -----------------------------------------------------------------------------
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| // File: usage_config.h
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| // -----------------------------------------------------------------------------
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| //
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| // This file defines the main usage reporting configuration interfaces and
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| // documents Abseil's supported built-in usage flags. If these flags are found
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| // when parsing a command-line, Abseil will exit the program and display
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| // appropriate help messages.
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| #ifndef ABSL_FLAGS_USAGE_CONFIG_H_
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| #define ABSL_FLAGS_USAGE_CONFIG_H_
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| 
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| #include <functional>
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| #include <string>
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| 
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| #include "absl/base/config.h"
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| #include "absl/strings/string_view.h"
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| 
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| // -----------------------------------------------------------------------------
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| // Built-in Usage Flags
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| // -----------------------------------------------------------------------------
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| //
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| // Abseil supports the following built-in usage flags. When passed, these flags
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| // exit the program and :
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| //
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| // * --help
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| //     Shows help on important flags for this binary
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| // * --helpfull
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| //     Shows help on all flags
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| // * --helpshort
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| //     Shows help on only the main module for this program
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| // * --helppackage
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| //     Shows help on all modules in the main package
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| // * --version
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| //     Shows the version and build info for this binary and exits
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| // * --only_check_args
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| //     Exits after checking all flags
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| // * --helpon
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| //     Shows help on the modules named by this flag value
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| // * --helpmatch
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| //     Shows help on modules whose name contains the specified substring
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| 
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| namespace absl {
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| ABSL_NAMESPACE_BEGIN
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| 
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| namespace flags_internal {
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| using FlagKindFilter = std::function<bool (absl::string_view)>;
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| }  // namespace flags_internal
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| 
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| // FlagsUsageConfig
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| //
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| // This structure contains the collection of callbacks for changing the behavior
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| // of the usage reporting routines in Abseil Flags.
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| struct FlagsUsageConfig {
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|   // Returns true if flags defined in the given source code file should be
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|   // reported with --helpshort flag. For example, if the file
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|   // "path/to/my/code.cc" defines the flag "--my_flag", and
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|   // contains_helpshort_flags("path/to/my/code.cc") returns true, invoking the
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|   // program with --helpshort will include information about --my_flag in the
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|   // program output.
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|   flags_internal::FlagKindFilter contains_helpshort_flags;
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| 
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|   // Returns true if flags defined in the filename should be reported with
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|   // --help flag. For example, if the file
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|   // "path/to/my/code.cc" defines the flag "--my_flag", and
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|   // contains_help_flags("path/to/my/code.cc") returns true, invoking the
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|   // program with --help will include information about --my_flag in the
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|   // program output.
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|   flags_internal::FlagKindFilter contains_help_flags;
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| 
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|   // Returns true if flags defined in the filename should be reported with
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|   // --helppackage flag. For example, if the file
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|   // "path/to/my/code.cc" defines the flag "--my_flag", and
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|   // contains_helppackage_flags("path/to/my/code.cc") returns true, invoking the
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|   // program with --helppackage will include information about --my_flag in the
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|   // program output.
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|   flags_internal::FlagKindFilter contains_helppackage_flags;
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| 
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|   // Generates string containing program version. This is the string reported
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|   // when user specifies --version in a command line.
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|   std::function<std::string()> version_string;
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| 
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|   // Normalizes the filename specific to the build system/filesystem used. This
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|   // routine is used when we report the information about the flag definition
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|   // location. For instance, if your build resides at some location you do not
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|   // want to expose in the usage output, you can trim it to show only relevant
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|   // part.
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|   // For example:
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|   //   normalize_filename("/my_company/some_long_path/src/project/file.cc")
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|   // might produce
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|   //   "project/file.cc".
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|   std::function<std::string(absl::string_view)> normalize_filename;
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| };
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| 
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| // SetFlagsUsageConfig()
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| //
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| // Sets the usage reporting configuration callbacks. If any of the callbacks are
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| // not set in usage_config instance, then the default value of the callback is
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| // used.
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| void SetFlagsUsageConfig(FlagsUsageConfig usage_config);
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| 
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| namespace flags_internal {
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| 
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| FlagsUsageConfig GetUsageConfig();
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| 
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| void ReportUsageError(absl::string_view msg, bool is_fatal);
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| 
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| }  // namespace flags_internal
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| ABSL_NAMESPACE_END
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| }  // namespace absl
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| 
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| extern "C" {
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| 
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| // Additional report of fatal usage error message before we std::exit. Error is
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| // fatal if is_fatal argument to ReportUsageError is true.
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| void AbslInternalReportFatalUsageError(absl::string_view);
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| 
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| }  // extern "C"
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| 
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| #endif  // ABSL_FLAGS_USAGE_CONFIG_H_
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