Add Flag files from rcpp branch.

This doesn't compile yet, I just need to move them to my main
development machine.

Flag.cc

@@ -0,0 +1,191 @@
+///
+/// \file Flag.h
+/// \author kyle 
+/// \created 2023-10-12
+/// \brief Flag defines a command-line flag parser.
+///
+/// \section COPYRIGHT
+///
+/// Copyright 2023 K. Isom <kyle@imap.cc>
+///
+/// Permission to use, copy, modify, and/or distribute this software for
+/// any purpose with or without fee is hereby granted, provided that
+/// the above copyright notice and this permission notice appear in all /// copies.
+///
+/// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+/// WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+/// WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+/// AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+/// DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA
+/// OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+/// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+/// PERFORMANCE OF THIS SOFTWARE.
+///
+
+
+#include <cstdint>
+#include <functional>
+#include <map>
+#include <regex>
+#include <vector>
+
+#include "Flag.h"
+
+
+namespace klib {
+
+
+static const std::regex	isFlag("^-[a-zA-Z0-9]+$", 
+			       std::regex_constants::nosubs);
+
+
+Flag::Flag(FlagType fType, std::string fName, std::string fDescription)
+    : Type(fType), WasSet(false), Name(fName), Description(fDescription)
+{
+}
+
+
+Flags::Flags(std::string fName)
+	: name(fName), description("")
+{
+}
+
+
+Flags::Flags(std::string fName, std::string fDescription)
+    : name(fName), description(fDescription)
+{
+}
+
+
+bool
+Flags::Register(std::string fName, FlagType fType, std::string fDescription)
+{
+	if (!std::regex_search(fName, isFlag)) {
+		return false;
+	}
+
+	if (this->flags.count(fName) != 0) {
+		return false;
+	}
+
+	auto flag = new Flag;
+	flag->Type = fType;
+	flag->WasSet = false;
+	flag->name = name;
+	this->desription = fDescription;
+	this->flags[fName] = flag;
+	return true;
+}
+
+
+Flag *
+Flags::Lookup(std::string fName)
+{
+	if (this->flags.count(fName) == 0) {
+		return nullptr;
+	}
+
+
+}
+
+
+OptFlagValue
+Flags::ValueOf(std::string fName)
+{
+	if (this->flags.count(fName)) {
+		return std::nullopt;
+	}
+
+	return OptFlagValue(this->flags[fName]->Value);
+}
+
+
+
+ParseStatus
+Flags::parseArg(int argc, char **argv, int &index)
+{
+	std::string	arg(argv[index]);
+
+	index++;
+	if (!std::regex_search(arg, isFlag)) {
+		return ParseStatus::EndOfFlags;
+	}
+
+	if (this->flags.count(arg) == 0) {
+		return ParseStatus::NotRegistered;
+	}
+
+	auto flag = flags[arg];
+	if (flag->Type == FlagType::Boolean) {
+		flag->WasSet = true;
+		flag->Value.b = true;
+		return ParseStatus::OK;
+	}
+
+	switch (flag->Type) {
+	default:
+		throw std::runtime_error("not handled");
+	}
+
+	return ParseStatus::OK;
+}
+
+
+ParseStatus
+Flags::Parse(int argc, char **argv)
+{
+	int	index = 1;
+
+	while (index != argc) {
+		auto result = this->parseArg(argc, argv, index);
+		switch (result) {
+		case ParseStatus::OK:
+			continue;
+
+		case ParseStatus::EndOfFlags:
+			while (index < argc) {
+				this->args.push_back(std::string(argv[index]));
+				index++;
+			}
+			continue;
+		case ParseStatus::EndOfFlags:
+		case ParseStatus::NotEnoughArgs:
+			// fall through //
+			return result;
+		default:
+			throw runtime_error("unhandled parse state");
+		}
+
+	}
+
+	return ParseStatus::OK;
+}
+
+
+size_t
+Flags::NumArgs()
+{
+	return this->args.size();
+}
+
+
+std::vector<std::string>
+Flags::Args()
+{
+	return this->args;
+}
+
+
+bool
+Flags::GetBool(std::string name, bool &flagValue)
+{
+	if (this->flags[name] == 0) {
+		return false;
+	}
+
+	return std::get<bool>(this->flags[name]->Value);
+}
+
+
+} // namespace klib
+

Flag.h

@@ -0,0 +1,111 @@
+///
+/// \file Flag.h
+/// \author kyle 
+/// \created 2023-10-12
+/// \brief Flag declares a command-line flag parser.
+///
+/// \section COPYRIGHT
+///
+/// Copyright 2023 K. Isom <kyle@imap.cc>
+///
+/// Permission to use, copy, modify, and/or distribute this software for
+/// any purpose with or without fee is hereby granted, provided that
+/// the above copyright notice and this permission notice appear in all /// copies.
+///
+/// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+/// WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+/// WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+/// AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+/// DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA
+/// OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+/// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+/// PERFORMANCE OF THIS SOFTWARE.
+///
+
+
+#include <cstdint>
+#include <functional>
+#include <map>
+#include <optional>
+#include <variant>
+#include <vector>
+
+
+namespace klib {
+
+
+
+enum class FlagType : uint8_t {
+	Unknown		= 0,
+	Boolean		= 1,
+	Integer		= 2,
+	UnsignedInteger	= 3,
+	String		= 4,
+};
+
+
+enum class ParseStatus : uint8_t {
+	OK		= 0,
+	EndOfFlags	= 1,
+	NotRegistered	= 2,	
+	NotEnoughArgs	= 3,
+};
+
+
+typedef std::variant<
+	std::string *,
+	bool *,
+	int64_t *,
+	uint64_t *> FlagValue;
+
+
+struct Flag {
+	Flag(FlagType fType, std::string fName, std::string fDescription);
+
+	FlagType	Type;
+	bool		WasSet;
+	std::string	Name;
+	std::string	Description;
+	FlagValue	Value;
+};
+typedef std::optional<FlagValue>	OptFlagValue;
+
+
+class Flags {
+public:
+	Flags(std::string fName);
+	Flags(std::string fName, std::string fDescription);
+
+	bool	Register(std::string fName, 
+			 FlagType fType,
+			 std::string fDescription);
+	Flag	*Lookup(std::string fName);
+	OptFlagValue
+		 ValueOf(std::string fName);
+
+	int	 Parse(int argc, char **argv);
+
+	void	 Usage(std::ostream &os, int exitCode);
+
+	size_t	 			NumArgs();
+	std::vector<std::string>	Args();
+	std::string			Arg(int index);
+
+	bool	GetBool(std::string name, bool &flagValue);
+	// bool	GetUnsignedInteger(std::string name, uint64_t &flagValue)
+	// bool	GetInteger(std::string name, int64_t &flagValue)
+	// bool	GetString(std::string name, std::string &flagValue)
+
+
+private:
+	ParseStatus		parseArg(int argc, char **argv, int &index);
+
+	std::string			name;
+	std::string			description;
+	std::vector<std::string>	args;
+	std::map<std::string, Flag *>	flags;
+};
+
+
+
+} // namespace klib