Class to simplify parsing command line options, and outputing help text. More...

Inheritance diagram for Laxkit::LaxOptions:

Public Member Functions
int	Verify ()
void	HelpHeader (const char *header_text)
	Create the top portion of help text, not option specific. Multiple calls will append.
const char *	HelpHeader ()
void	UsageLine (const char *usage_line)
void	OptionsHeader (const char *usage_line)
int	NewGroup (const char *group_header_text)
int	Add (const char long_option, int short_option, int has_param, const char nhelp_text, int nid=0, const char *opt_example=NULL)
void	Help (FILE *file=NULL, int columns=-1)
	Output the help to the given file as plain text. Defaults to stderr if NULL.
void	HelpHtml (FILE *file=NULL)
	Output a man page formatted template, listing the options.
void	HelpMan (FILE *file=NULL)
	Output an html snippet formatted template, listing the options.
int	Parse (int argc, char *argv, int argerr)
	Parse options.
int	Review (int which)
	Set which set of arguments to review, 1 for remaining non-options, 0 for options.
LaxOption *	error ()
	When a missing parameter of unknown option is encountered in Parse(), use this to return the object for more info.
LaxOption *	start ()
	Start looping with any option arguments, and return the first of those, if any.
LaxOption *	remaining ()
	Start looping with any non-option arguments, and return the first of those, if any.
LaxOption *	next ()
LaxOption *	find (const char *long_option, int short_option)
int	more ()
	Return number of remaining options.

Protected Attributes
char *	helpheader
char *	optionsheader
char *	usageline
int	curgroup
int	curitem
int	loop_which
int	first_remaining
int	erred
Protected Attributes inherited from Laxkit::PtrStack< LaxOption >
char *	islocal
int	n
LaxOption **	e
int	max
int	delta
char	arrays

Additional Inherited Members
Protected Member Functions inherited from Laxkit::PtrStack< LaxOption >
	PtrStack (char nar=1)
virtual LaxOption *	operator[] (int i)
virtual void	flush ()
virtual int	howmany ()
virtual void	swap (int i1, int i2)
virtual int	push (LaxOption *nd, char local=-1, int where=-1)
virtual int	popp (LaxOption topop, int local=NULL)
virtual int	pop (LaxOption &popped, int which=-1, int local=NULL)
virtual LaxOption *	pop (int which=-1, int *local=NULL)
virtual int	findindex (LaxOption *t)
virtual int	remove (int which=-1)
virtual int	pushnodup (LaxOption *nd, char local, int where=-1)
virtual void	Delta (int ndelta)
virtual int	Delta ()
virtual LaxOption **	extractArrays (char *local=NULL, int nn=NULL)
virtual int	insertArrays (LaxOption *a, char nl, int nn)

Detailed Description

Class to simplify parsing command line options, and outputing help text.

This class currently assumes that each option can appear once. They can have long and short options with descriptions, and simple grouping of options.

In outputting, it is currently assumed that the option example is short, and contained on one line. The help text per option is wrapped to fit within a certain number of columns, and is assumed to be able to be read as a single line (or a wrapped single line).

You would Add() new options to a LaxOptions object, then when done, call Parse(). Afterwards you can loop over parsed options with start(), next(), and remaining().

Todo:: perhaps allow duplicate options, like "-i some/dir -i some/other/dir"

Member Function Documentation

int Laxkit::LaxOptions::Add	(	const char *	long_option,
		int	short_option,
		int	has_param,
		const char *	nhelp_text,
		int	nid = `0`,
		const char *	opt_example = `NULL`
	)

If has_param==1, then opt_example is used as the text to indicate the argument in the help text. If opt_example is NULL, then use "arg" instead. If has_param==2, then opt_example is used as the whole option example.

Parameters:

has_param	nonzero if the option takes a parameter, else it doesn't
opt_example	like '–list, -l "all"' instead of just "--list, -l"

LaxOption * Laxkit::LaxOptions::error ( )

When a missing parameter of unknown option is encountered in Parse(), use this to return the object for more info.

Particularly, for missing parameters, this gives you easy access to the help text corresponding to that option.

LaxOption * Laxkit::LaxOptions::find	(	const char *	long_option,
		int	short_option
	)

Find an option corresponding to either long_option or short_option (when non-null).

void Laxkit::LaxOptions::Help	(	FILE *	file = `NULL`,
		int	columns = `-1`
	)

Output the help to the given file as plain text. Defaults to stderr if NULL.

If columns<=0, then use ioctl(0, TIOCGWINSZ, &w), w.ws_col for the number of columns.

References newstr().

void Laxkit::LaxOptions::HelpHtml ( FILE * file = NULL )

Output a man page formatted template, listing the options.

The idea here is to simplify creation of man pages, to automatically get a formatted option list, which is otherwise very tedious to produce.

If file==NULL, then use stdout.

void Laxkit::LaxOptions::HelpMan ( FILE * file = NULL )

Output an html snippet formatted template, listing the options.

Output a table with 4 columns: long form, short form, parameter example, description

If file==NULL, then use stdout.

int Laxkit::LaxOptions::Parse	(	int	argc,
		char **	argv,
		int *	argerr
	)

Parse options.

This follows basic conventions that long options are preceeded with "--". Any number of short options can follow a "-" unless it expects a parameter. An argument of only "--" is ignored and signifies that all following arguments are not options. Parameters can be specified with "--long-option arg", '-s arg' for short options, or -abcd for multiple short options.

The original argv is not modified.

On success, returns the number of options found and parsed, which will be 0 or more. If there is a an unknown option, then parsing stops, argerr is set to the index of argv for the offending item and -1 is returned. If there is a missing parameter, then parsing stops, argerr is set to the index of argv for the offending item and -2 is returned.

Note that argv[0] is ignored.

References makestr().

int Laxkit::LaxOptions::Review ( int which )

Set which set of arguments to review, 1 for remaining non-options, 0 for options.

Sets loop counter to 0.

The documentation for this class was generated from the following files:

laxoptions.h
laxoptions.cc

Public Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation