// ****************************************************************************
// ^FILE: options.h - option parsing classes
//
// ^DESCRIPTION:
// This file defines classes used to parse command-line options.
// Options may be parsed from an array of strings, or from any structure
// for which a corresponding option-iterator exists.
//
// ^HISTORY:
// 03/06/92 Brad Appleton <bradapp@enteract.com> Created
//
// 03/23/93 Brad Appleton <bradapp@enteract.com>
// - Added OptIstreamIter class
//
// 03/08/94 Brad Appleton <bradapp@enteract.com>
// - Added Options::reset() member function
//
// 07/31/97 Brad Appleton <bradapp@enteract.com>
// - Added PARSE_POS control flag and POSITIONAL return value
//
// 04/30/06 Chris Reed
// - Updated to modern C++ and STL
// - Converted comments to doxygen style
// ^^**************************************************************************
#ifndef _options_h
#define _options_h
#ifdef USE_STDIO
#include <stdio.h>
#else
#include <iostream>
#endif
//! Abstract class to iterate through options/arguments
//!
class OptIter {
public:
OptIter(void) {}
virtual ~OptIter(void);
//! curr() returns the current item in the iterator without
//! advancing on to the next item. If we are at the end of items
//! then NULL is returned.
virtual const char *
curr(void) = 0;
//! next() advances to the next item.
virtual void
next(void) = 0;
//! operator() returns the current item in the iterator and then
//! advances on to the next item. If we are at the end of items
//! then NULL is returned.
virtual const char *
operator()(void);
} ;
//! Abstract class for a rewindable OptIter
//!
class OptIterRwd : public OptIter {
public:
OptIterRwd(void);
virtual ~OptIterRwd(void);
virtual const char *
curr(void) = 0;
virtual void
next(void) = 0;
virtual const char *
operator()(void) = 0;
//! rewind() resets the "current-element" to the first one in the "list"
virtual void
rewind(void) = 0;
} ;
//! Class to iterate through an array of tokens. The array may be terminated
//! by NULL or a count containing the number of tokens may be given.
//!
class OptArgvIter : public OptIterRwd {
private:
int ndx; // index of current arg
int ac; // arg count
const char * const * av; // arg vector
public:
OptArgvIter(const char * const argv[])
: av(argv), ac(-1), ndx(0) {}
OptArgvIter(int argc, const char * const argv[])
: av(argv), ac(argc), ndx(0) {}
virtual
~OptArgvIter(void);
virtual const char *
curr(void);
virtual void
next(void);
virtual const char *
operator()(void);
virtual void
rewind(void);
//! index returns the current index to use for argv[]
int index(void) { return ndx; }
} ;
//! Class to iterate through a string containing delimiter-separated tokens
//!
class OptStrTokIter : public OptIterRwd {
private:
unsigned len; // length of token-string
const char * str; // the token-string
const char * seps; // delimiter-set (separator-characters)
const char * cur; // current token
char * tokstr; // our copy of the token-string
static const char * default_delims; // default delimiters = whitespace
public:
OptStrTokIter(const char * tokens, const char * delimiters =0);
virtual
~OptStrTokIter(void);
virtual const char *
curr(void);
virtual void
next(void);
virtual const char *
operator()(void);
virtual void
rewind(void);
//! delimiters() with NO arguments returns the current set of delimiters,
//! If an argument is given then it is used as the new set of delimiters.
const char *
delimiters(void) { return seps; }
void
delimiters(const char * delims) {
seps = (delims) ? delims : default_delims ;
}
} ;
//! OptIstreamIter is a class for iterating over arguments that come
//! from an input stream. Each line of the input stream is considered
//! to be a set of white-space separated tokens. If the the first
//! non-white character on a line is '#' ('!' for VMS systems) then
//! the line is considered a comment and is ignored.
//!
//! \note If a line is more than 1022 characters in length then we
//! treat it as if it were several lines of length 1022 or less.
//!
//! \note The string tokens returned by this iterator are pointers
//! to temporary buffers which may not necessarily stick around
//! for too long after the call to curr() or operator(), hence
//! if you need the string value to persist - you will need to
//! make a copy.
//!
class OptIstreamIter : public OptIter {
private:
std::istream & is ;
OptStrTokIter * tok_iter ;
void
fill(void);
public:
static const unsigned MAX_LINE_LEN ;
OptIstreamIter(std::istream & input);
virtual
~OptIstreamIter(void);
virtual const char *
curr(void);
virtual void
next(void);
virtual const char *
operator()(void);
} ;
//! \brief parse command-line options
//!
//! \section Synopsis
//! \code
//! #include <options.h>
//!
//! Options opts(cmdname, optv);
//! char cmdname[], *optv[];
//! \endcode
//! \section Description
//! The Options constructor expects a command-name (usually argv[0]) and
//! a pointer to an array of strings. The last element in this array MUST
//! be NULL. Each non-NULL string in the array must have the following format:
//!
//! The 1st character must be the option-name ('c' for a -c option).
//!
//! The 2nd character must be one of '|', '?', ':', '*', or '+'.
//! '|' -- indicates that the option takes NO argument;
//! '?' -- indicates that the option takes an OPTIONAL argument;
//! ':' -- indicates that the option takes a REQUIRED argument;
//! '*' -- indicates that the option takes 0 or more arguments;
//! '+' -- indicates that the option takes 1 or more arguments;
//!
//! The remainder of the string must be the long-option name.
//!
//! If desired, the long-option name may be followed by one or more
//! spaces and then by the name of the option value. This name will
//! be used when printing usage messages. If the option-value-name
//! is not given then the string "<value>" will be used in usage
//! messages.
//!
//! One may use a space to indicate that a particular option does not
//! have a corresponding long-option. For example, "c: " (or "c:")
//! means the -c option takes a value & has NO corresponding long-option.
//!
//! To specify a long-option that has no corresponding single-character
//! option is a bit trickier: Options::operator() still needs an "option-
//! character" to return when that option is matched. One may use a whitespace
//! character or a non-printable character as the single-character option
//! in such a case. (hence " |hello" would only match "--hello").
//!
//! \section Exceptions Exceptions to the above
//! If the 1st character of the string is '-', then the rest of the
//! string must correspond to the above format, and the option is
//! considered to be a hidden-option. This means it will be parsed
//! when actually matching options from the command-line, but will
//! NOT show-up if a usage message is printed using the usage() member
//! function. Such an example might be "-h|hidden". If you want to
//! use any "dummy" options (options that are not parsed, but that
//! to show up in the usage message), you can specify them along with
//! any positional parameters to the usage() member function.
//!
//! If the 2nd character of the string is '\0' then it is assumed
//! that there is no corresponding long-option and that the option
//! takes no argument (hence "f", and "f| " are equivalent).
//!
//! \code
//! const char * optv[] = {
//! "c:count <number>",
//! "s?str <string>",
//! "x",
//! " |hello",
//! "g+groups <newsgroup>",
//! NULL
//! } ;
//! \endcode
//! optv[] now corresponds to the following:
//!
//! usage: cmdname [-c|--count <number>] [-s|--str [<string>]]
//! [-x] [--hello] [-g|--groups <newsgroup> ...]
//!
//! Long-option names are matched case-insensitive and only a unique prefix
//! of the name needs to be specified.
//!
//! Option-name characters are case-sensitive!
//!
//! \section Caveat
//! Because of the way in which multi-valued options and options with optional
//! values are handled, it is NOT possible to supply a value to an option in
//! a separate argument (different argv[] element) if the value is OPTIONAL
//! and begins with a '-'. What this means is that if an option "-s" takes an
//! optional value value and you wish to supply a value of "-foo" then you must
//! specify this on the command-line as "-s-foo" instead of "-s -foo" because
//! "-s -foo" will be considered to be two separate sets of options.
//!
//! A multi-valued option is terminated by another option or by the end-of
//! options. The following are all equivalent (if "-l" is a multi-valued
//! option and "-x" is an option that takes no value):
//!
//! cmdname -x -l item1 item2 item3 -- arg1 arg2 arg3
//! cmdname -x -litem1 -litem2 -litem3 -- arg1 arg2 arg3
//! cmdname -l item1 item2 item3 -x arg1 arg2 arg3
//!
//!
//! \code
//! #include <options.h>
//!
//! static const char * optv[] = {
//! "H|help",
//! "c:count <number>",
//! "s?str <string>",
//! "x",
//! " |hello",
//! "g+groups <newsgroup>",
//! NULL
//! } ;
//!
//! main(int argc, char * argv[]) {
//! int optchar;
//! const char * optarg;
//! const char * str = "default_string";
//! int count = 0, xflag = 0, hello = 0;
//! int errors = 0, ngroups = 0;
//!
//! Options opts(*argv, optv);
//! OptArgvIter iter(--argc, ++argv);
//!
//! while( optchar = opts(iter, optarg) ) {
//! switch (optchar) {
//! case 'H' :
//! opts.usage(cout, "files ...");
//! exit(0);
//! break;
//! case 'g' :
//! ++ngroups; break; //! the groupname is in "optarg"
//! case 's' :
//! str = optarg; break;
//! case 'x' :
//! ++xflag; break;
//! case ' ' :
//! ++hello; break;
//! case 'c' :
//! if (optarg == NULL) ++errors;
//! else count = (int) atol(optarg);
//! break;
//! default : ++errors; break;
//! } //!switch
//! }
//!
//! if (errors || (iter.index() == argc)) {
//! if (! errors) {
//! cerr << opts.name() << ": no filenames given." << endl ;
//! }
//! opts.usage(cerr, "files ...");
//! exit(1);
//! }
//!
//! cout << "xflag=" << ((xflag) ? "ON" : "OFF") << endl
//! << "hello=" << ((hello) ? "YES" : "NO") << endl
//! << "count=" << count << endl
//! << "str=\"" << ((str) ? str : "No value given!") << "\"" << endl
//! << "ngroups=" << ngroups << endl ;
//!
//! if (iter.index() < argc) {
//! cout << "files=" ;
//! for (int i = iter.index() ; i < argc ; i++) {
//! cout << "\"" << argv[i] << "\" " ;
//! }
//! cout << endl ;
//! }
//! }
//! \endcode
class Options {
private:
unsigned explicit_end : 1; //!< were we terminated because of "--"?
unsigned optctrls : 7; //!< control settings (a set of OptCtrl masks)
const char * const * optvec; //!< vector of option-specifications (last=NULL)
const char * nextchar; //!< next option-character to process
const char * listopt; //!< last list-option we matched
const char * cmdname; //!< name of the command
void
check_syntax(void) const;
const char *
match_opt(char opt, int ignore_case =0) const;
const char *
match_longopt(const char * opt, int len, int & ambiguous) const;
int
parse_opt(OptIter & iter, const char * & optarg);
int
parse_longopt(OptIter & iter, const char * & optarg);
public:
enum OptCtrl {
DEFAULT = 0x00, //!< Default setting
ANYCASE = 0x01, //!< Ignore case when matching short-options
QUIET = 0x02, //!< Dont print error messages
PLUS = 0x04, //!< Allow "+" as a long-option prefix
SHORT_ONLY = 0x08, //!< Dont accept long-options
LONG_ONLY = 0x10, //!< Dont accept short-options
//!< (also allows "-" as a long-option prefix).
NOGUESSING = 0x20, //!< Normally, when we see a short (long) option
//!< on the command line that doesnt match any
//!< known short (long) options, then we try to
//!< "guess" by seeing if it will match any known
//!< long (short) option. Setting this mask prevents
//!< this "guessing" from occurring.
PARSE_POS = 0x40 //!< By default, Options will not present positional
//!< command-line arguments to the user and will
//!< instead stop parsing when the first positonal
//!< argument has been encountered. If this flag
//!< is given, Options will present positional
//!< arguments to the user with a return code of
//!< POSITIONAL; ENDOPTS will be returned only
//!< when the end of the argument list is reached.
} ;
//! Error return values for operator()
//!
enum OptRC {
ENDOPTS = 0,
BADCHAR = -1,
BADKWD = -2,
AMBIGUOUS = -3,
POSITIONAL = -4
} ;
Options(const char * name, const char * const optv[]);
virtual
~Options(void);
//! name() returns the command name
const char *
name(void) const { return cmdname; }
//! ctrls() (with no arguments) returns the existing control settings
unsigned
ctrls(void) const { return optctrls; }
//! ctrls() (with 1 argument) sets new control settings
void
ctrls(unsigned newctrls) { optctrls = newctrls; }
//! reset for another pass to parse for options
void
reset(void) { nextchar = listopt = NULL; }
//! usage() prints options usage (followed by any positional arguments
//! listed in the parameter "positionals") on the given outstream
void
usage(std::ostream & os, const char * positionals) const ;
//! operator() iterates through the arguments as necessary (using the
//! given iterator) and returns the character value of the option
//! (or long-option) that it matched. If the option has a value
//! then the value given may be found in optarg (otherwise optarg
//! will be NULL).
//!
//! 0 is returned upon end-of-options. At this point, "iter" may
//! be used to process any remaining positional parameters. If the
//! PARSE_POS control-flag is set then 0 is returned only when all
//! arguments in "iter" have been exhausted.
//!
//! If an invalid option is found then BADCHAR is returned and *optarg
//! is the unrecognized option character.
//!
//! If an invalid long-option is found then BADKWD is returned and optarg
//! points to the bad long-option.
//!
//! If an ambiguous long-option is found then AMBIGUOUS is returned and
//! optarg points to the ambiguous long-option.
//!
//! If the PARSE_POS control-flag is set then POSITIONAL is returned
//! when a positional argument is encountered and optarg points to
//! the positonal argument (and "iter" is advanced to the next argument
//! in the iterator).
//!
//! Unless Options::QUIET is used, missing option-arguments and
//! invalid options (and the like) will automatically cause error
//! messages to be issued to cerr.
int
operator()(OptIter & iter, const char * & optarg) ;
//! Call this member function after operator() has returned 0
//! if you want to know whether or not options were explicitly
//! terminated because "--" appeared on the command-line.
//!
int
explicit_endopts() const { return explicit_end; }
} ;
#endif /* _options_h */