Add parse_options helper for parsing cmd line args

Makefile

@@ -3,7 +3,7 @@ CXXFLAGS := -Wall -pedantic -Wno-long-long -O2
 LDFLAGS := -lcrypto
 PREFIX := /usr/local
 
-OBJFILES = git-crypt.o commands.o crypto.o gpg.o key.o util.o
+OBJFILES = git-crypt.o commands.o crypto.o gpg.o key.o util.o parse_options.o
 
 all: git-crypt
 

commands.cpp

@@ -33,6 +33,7 @@
 #include "util.hpp"
 #include "key.hpp"
 #include "gpg.hpp"
+#include "parse_options.hpp"
 #include <unistd.h>
 #include <stdint.h>
 #include <algorithm>
@@ -890,58 +891,28 @@ int refresh (int argc, char** argv) // TODO: do a force checkout, much like in u
 
 int status (int argc, char** argv)
 {
-	int		argi = 0;
-
 	// Usage:
 	//  git-crypt status -r [-z]			Show repo status
 	//  git-crypt status [-e | -u] [-z] [FILE ...]	Show encrypted status of files
 	//  git-crypt status -f				Fix unencrypted blobs
 
-	// Flags:
-	//  -e show encrypted files only
-	//  -u show unencrypted files only
-	//  -f fix problems
-	//  -z machine-parseable output
-	//  -r show repo status only
-
 	// TODO: help option / usage output
 
-	bool		repo_status_only = false;
-	bool		show_encrypted_only = false;
-	bool		show_unencrypted_only = false;
-	bool		fix_problems = false;
-	bool		machine_output = false;
+	bool		repo_status_only = false;	// -r show repo status only
+	bool		show_encrypted_only = false;	// -e show encrypted files only
+	bool		show_unencrypted_only = false;	// -u show unencrypted files only
+	bool		fix_problems = false;		// -f fix problems
+	bool		machine_output = false;		// -z machine-parseable output
 
-	while (argi < argc && argv[argi][0] == '-') {
-		if (std::strcmp(argv[argi], "--") == 0) {
-			++argi;
-			break;
-		}
-		const char*	flags = argv[argi] + 1;
-		while (char flag = *flags++) {
-			switch (flag) {
-			case 'r':
-				repo_status_only = true;
-				break;
-			case 'e':
-				show_encrypted_only = true;
-				break;
-			case 'u':
-				show_unencrypted_only = true;
-				break;
-			case 'f':
-				fix_problems = true;
-				break;
-			case 'z':
-				machine_output = true;
-				break;
-			default:
-				std::clog << "Error: unknown option `" << flag << "'" << std::endl;
-				return 2;
-			}
-		}
-		++argi;
-	}
+	Options_list	options;
+	options.push_back(Option_def("-r", &repo_status_only));
+	options.push_back(Option_def("-e", &show_encrypted_only));
+	options.push_back(Option_def("-u", &show_unencrypted_only));
+	options.push_back(Option_def("-f", &fix_problems));
+	options.push_back(Option_def("--fix", &fix_problems));
+	options.push_back(Option_def("-z", &machine_output));
+
+	int		argi = parse_options(options, argc, argv);
 
 	if (repo_status_only) {
 		if (show_encrypted_only || show_unencrypted_only) {

git-crypt.cpp

@@ -34,6 +34,7 @@
 #include "crypto.hpp"
 #include "key.hpp"
 #include "gpg.hpp"
+#include "parse_options.hpp"
 #include <cstring>
 #include <unistd.h>
 #include <iostream>
@@ -188,6 +189,9 @@ try {
 } catch (const Crypto_error& e) {
 	std::cerr << "git-crypt: Crypto error: " << e.where << ": " << e.message << std::endl;
 	return 1;
+} catch (const Option_error& e) {
+	std::cerr << "git-crypt: Error: " << e.option_name << ": " << e.message << std::endl;
+	return 1;
 } catch (Key_file::Incompatible) {
 	std::cerr << "git-crypt: This repository contains a incompatible key file.  Please upgrade git-crypt." << std::endl;
 	return 1;

parse_options.cpp

@@ -0,0 +1,118 @@
+/*
+ * Copyright 2014 Andrew Ayer
+ *
+ * This file is part of git-crypt.
+ *
+ * git-crypt is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * git-crypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with git-crypt.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Additional permission under GNU GPL version 3 section 7:
+ *
+ * If you modify the Program, or any covered work, by linking or
+ * combining it with the OpenSSL project's OpenSSL library (or a
+ * modified version of that library), containing parts covered by the
+ * terms of the OpenSSL or SSLeay licenses, the licensors of the Program
+ * grant you additional permission to convey the resulting work.
+ * Corresponding Source for a non-source form of such a combination
+ * shall include the source code for the parts of OpenSSL used as well
+ * as that of the covered work.
+ */
+
+#include "parse_options.hpp"
+#include <cstring>
+
+
+static const Option_def* find_option (const Options_list& options, const std::string& name)
+{
+	for (Options_list::const_iterator opt(options.begin()); opt != options.end(); ++opt) {
+		if (opt->name == name) {
+			return &*opt;
+		}
+	}
+	return 0;
+}
+
+int parse_options (const Options_list& options, int argc, char** argv)
+{
+	int	argi = 0;
+
+	while (argi < argc && argv[argi][0] == '-') {
+		if (std::strcmp(argv[argi], "--") == 0) {
+			++argi;
+			break;
+		} else if (std::strncmp(argv[argi], "--", 2) == 0) {
+			std::string			option_name;
+			const char*			option_value = 0;
+			if (char* eq = std::strchr(argv[argi], '=')) {
+				option_name.assign(argv[argi], eq);
+				option_value = eq + 1;
+			} else {
+				option_name = argv[argi];
+			}
+			++argi;
+
+			const Option_def*		opt(find_option(options, option_name));
+			if (!opt) {
+				throw Option_error(option_name, "Invalid option");
+			}
+
+			if (opt->is_set) {
+				*opt->is_set = true;
+			}
+			if (opt->value) {
+				if (option_value) {
+					*opt->value = option_value;
+				} else {
+					if (argi >= argc) {
+						throw Option_error(option_name, "Option requires a value");
+					}
+					*opt->value = argv[argi];
+					++argi;
+				}
+			} else {
+				if (option_value) {
+					throw Option_error(option_name, "Option takes no value");
+				}
+			}
+		} else {
+			const char*			arg = argv[argi] + 1;
+			++argi;
+			while (*arg) {
+				std::string		option_name("-");
+				option_name.push_back(*arg);
+				++arg;
+
+				const Option_def*	opt(find_option(options, option_name));
+				if (!opt) {
+					throw Option_error(option_name, "Invalid option");
+				}
+				if (opt->is_set) {
+					*opt->is_set = true;
+				}
+				if (opt->value) {
+					if (*arg) {
+						*opt->value = arg;
+					} else {
+						if (argi >= argc) {
+							throw Option_error(option_name, "Option requires a value");
+						}
+						*opt->value = argv[argi];
+						++argi;
+					}
+					break;
+				}
+			}
+		}
+	}
+	return argi;
+}

parse_options.hpp

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2014 Andrew Ayer
+ *
+ * This file is part of git-crypt.
+ *
+ * git-crypt is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * git-crypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with git-crypt.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Additional permission under GNU GPL version 3 section 7:
+ *
+ * If you modify the Program, or any covered work, by linking or
+ * combining it with the OpenSSL project's OpenSSL library (or a
+ * modified version of that library), containing parts covered by the
+ * terms of the OpenSSL or SSLeay licenses, the licensors of the Program
+ * grant you additional permission to convey the resulting work.
+ * Corresponding Source for a non-source form of such a combination
+ * shall include the source code for the parts of OpenSSL used as well
+ * as that of the covered work.
+ */
+
+#ifndef PARSE_OPTIONS_HPP
+#define PARSE_OPTIONS_HPP
+
+#include <string>
+#include <vector>
+
+struct Option_def {
+	std::string	name;
+	bool*		is_set;
+	const char**	value;
+
+	Option_def () : is_set(0), value(0) { }
+	Option_def (const std::string& arg_name, bool* arg_is_set)
+	: name(arg_name), is_set(arg_is_set), value(0) { }
+	Option_def (const std::string& arg_name, const char** arg_value)
+	: name(arg_name), is_set(0), value(arg_value) { }
+};
+
+typedef std::vector<Option_def> Options_list;
+
+int parse_options (const Options_list& options, int argc, char** argv);
+
+struct Option_error {
+	std::string	option_name;
+	std::string	message;
+
+	Option_error (const std::string& n, const std::string& m) : option_name(n), message(m) { }
+};
+
+#endif