X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Fcore%2Fgetopt.h;h=911934ac08adb7399bbd914b6778a8df8eb99f03;hp=ea1f7d36a33fcea90ba552e58cb8b7546e462f34;hb=b27a278d8ab85afbad191d14962cc33e894718d4;hpb=d3b4cafbbb684a6f65ee9cc19162f2546c5326cb diff --git a/source/core/getopt.h b/source/core/getopt.h index ea1f7d3..911934a 100644 --- a/source/core/getopt.h +++ b/source/core/getopt.h @@ -22,6 +22,32 @@ public: }; +/** +Command line option processor. Both short and long options are supported, with +optional and required arguments. Automatic help text generation is also +available. + +Short options begin with a single dash and are identified by a single letter. +Multiple short options may be grouped if they take no arguments; for example, +the string "-abc" could be interpreted as having the options 'a', 'b' and 'c'. +If the option takes an argument and there are unused characters in the argv +element, then those characters are interpreted as the argument. Otherwise the +next element is taken as the argument. An optional argument must be given in +the same element. + +Long options begin with a double dash and are identified by an arbitrary +string. An argument can be specified either in the same argv element, +separated by an equals sign, or in the next element. As with short options, +an optional argument must be in the same element. + +A single option may have both alternative forms, but must always have at least +a long form. This is to encourage self-documenting options; it's much easier +to remember words than letters. + +A built-in --help option is provided and will output a list of options and +their associated help texts. An application may override this by providing +its own option with the same name. +*/ class GetOpt { public: @@ -31,111 +57,145 @@ public: OPTIONAL_ARG, REQUIRED_ARG }; - - class OptBase + + class Option + { + protected: + Option() { } + public: + virtual ~Option() { } + + /// Sets help text for the option. + virtual Option &set_help(const std::string &) = 0; + + /** Sets help text for the option, with a placeholder metavariable. The + metavariable is used to denote the argument in the option list. */ + virtual Option &set_help(const std::string &, const std::string &) = 0; + + virtual Option &bind_seen_count(unsigned &) = 0; + + /// Returns the number of times this option was seen on the command line. + virtual unsigned get_seen_count() const = 0; + }; + +private: + class Store + { + protected: + Store() { } + public: + virtual ~Store() { } + + virtual Store *clone() const = 0; + + virtual void store() = 0; + virtual void store(const std::string &) = 0; + }; + + class OptionImpl: public Option { protected: char shrt; std::string lng; ArgType arg_type; unsigned seen_count; + unsigned *ext_seen_count; std::string help; std::string metavar; + Store *store; - OptBase(char, const std::string &, ArgType); public: - virtual ~OptBase() { } + OptionImpl(char, const std::string &, const Store &, ArgType); + virtual ~OptionImpl(); - OptBase &set_help(const std::string &); - OptBase &set_help(const std::string &, const std::string &); + virtual OptionImpl &set_help(const std::string &); + virtual OptionImpl &set_help(const std::string &, const std::string &); + virtual OptionImpl &bind_seen_count(unsigned &); char get_short() const { return shrt; } const std::string &get_long() const { return lng; } ArgType get_arg_type() const { return arg_type; } const std::string &get_help() const { return help; } const std::string &get_metavar() const { return metavar; } - unsigned get_seen_count() const { return seen_count; } + virtual unsigned get_seen_count() const { return seen_count; } void process(); void process(const std::string &); - protected: - virtual void store() = 0; - virtual void store(const std::string &) = 0; }; -private: template - class Option: public OptBase + class SimpleStore: public Store { private: T &data; public: - Option(char s, const std::string &l, T &d, ArgType a): OptBase(s, l, a), data(d) { } + SimpleStore(T &d): data(d) { } + + virtual SimpleStore *clone() const + { return new SimpleStore(data); } virtual void store() { } virtual void store(const std::string &a) - { - try - { - data = lexical_cast(a); - } - catch(const lexical_error &e) - { - throw usage_error("Invalid argument for --"+lng+" ("+e.what()+")"); - } - } + { data = lexical_cast(a); } }; template - class ListOption: public OptBase + class ListStore: public Store { private: T &data; public: - ListOption(char s, const std::string &l, T &d, ArgType a): OptBase(s, l, a), data(d) - { if(arg_type!=REQUIRED_ARG) throw std::invalid_argument("ListOption arg_type!=REQUIRED"); } + ListStore(T &d): data(d) { } + + virtual ListStore *clone() const + { return new ListStore(data); } virtual void store() { } virtual void store(const std::string &a) - { - try - { - data.push_back(lexical_cast(a)); - } - catch(const lexical_error &e) - { - throw usage_error("Invalid argument for --"+lng+" ("+e.what()+")"); - } - } + { data.push_back(lexical_cast(a)); } }; + typedef std::list OptionList; + bool help; - std::list opts; + OptionList opts; std::vector args; public: GetOpt(); ~GetOpt(); + /// Returns any non-option arguments encountered during processing. const std::vector &get_args() const { return args; } + /** Adds an option with both short and long forms. Processing depends on + the type of the destination variable and whether an argument is taken or + not. With an argument, the value is lexical_cast to appropriate type and + stored in the destination. Without an argument, a bool will be set to true + and an unsigned will be incremented; any other type will be ignored. */ template - OptBase &add_option(char s, const std::string &l, T &d, ArgType a = NO_ARG) - { opts.push_back(new Option(s, l, d, a)); return *opts.back(); } - + Option &add_option(char s, const std::string &l, T &d, ArgType a = NO_ARG) + { return add_option(s, l, SimpleStore(d), a); } + + /** Adds an option with both short and long forms. The option may be + specified multiple times, and the argument from each occurrence is stored in + the list. The argument type must be REQUIRED_ARG. */ template - OptBase &add_option(char s, const std::string &l, std::list &d, ArgType a = REQUIRED_ARG) - { opts.push_back(new ListOption >(s, l, d, a)); return *opts.back(); } - + Option &add_option(char s, const std::string &l, std::list &d, ArgType a = REQUIRED_ARG) + { return add_option(s, l, ListStore >(d), a); } + + /** Adds an option with only a long form. */ template - OptBase &add_option(const std::string &l, T &d, ArgType a) + Option &add_option(const std::string &l, T &d, ArgType a) { return add_option(0, l, d, a); } private: - OptBase &get_option(char); - OptBase &get_option(const std::string &); + OptionImpl &add_option(char, const std::string &, const Store &, ArgType); + + OptionImpl &get_option(char); + OptionImpl &get_option(const std::string &); public: /** Processes argc/argv style command line arguments. The contents of argv @@ -158,16 +218,16 @@ public: std::string generate_help() const; }; -template<> inline void GetOpt::Option::store() +template<> inline void GetOpt::SimpleStore::store() { data = true; } -template<> inline void GetOpt::Option::store() +template<> inline void GetOpt::SimpleStore::store() { ++data; } -template<> inline void GetOpt::Option::store(const std::string &a) +template<> inline void GetOpt::SimpleStore::store(const std::string &a) { data = a; } -template<> inline void GetOpt::ListOption >::store(const std::string &a) +template<> inline void GetOpt::ListStore >::store(const std::string &a) { data.push_back(a); } } // namespace Msp