3 * $Id: mdwopt.h,v 1.5 1999/05/19 20:23:59 mdw Exp $
5 * Options parsing, similar to GNU @getopt_long@
7 * (c) 1996 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of many programs.
14 * `mdwopt' is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * `mdwopt' is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with `mdwopt'; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 /*----- Revision history --------------------------------------------------*
33 * Revision 1.5 1999/05/19 20:23:59 mdw
34 * Change naming to match newer mLib conventions.
36 * Revision 1.4 1999/05/15 10:25:38 mdw
37 * Fix copyright information.
39 * Revision 1.3 1999/05/14 18:51:42 mdw
40 * Reformat the LGPL notice slightly.
42 * Revision 1.2 1999/05/13 22:57:23 mdw
43 * Change `-ise' to `-ize' throughout.
45 * Revision 1.1.1.1 1999/05/05 19:23:47 mdw
46 * New import. The old CVS repository was lost in a disk disaster.
48 * --- Previous lives ---
51 * Revision 1.5 1997/08/09 20:27:59 mdw
52 * Fix spelling of `Licensing'.
54 * Revision 1.4 1997/07/29 21:11:49 mdw
55 * Fixed address of the FSF.
57 * Revision 1.3 1996/12/31 19:41:33 mdw
60 * Revision 1.2 1996/11/23 00:47:25 mdw
61 * Added `MdwOpt' object from the `anagram' source code.
63 * Revision 1.1 1996/09/24 18:01:43 mdw
71 /*----- Options handling structures ---------------------------------------*/
77 /* --- @mdwopt_data@ --- *
79 * Contains all the information needed by the @mdwopt@ routine to do its
80 * work. Try not to use @prog@ any more. If you're using mLib, the @quis@/
81 * @ego@ interface works better.
86 /* --- Public variables --- */
88 char *arg
; /* Arg of current option, or 0 */
89 int opt
; /* Value of current option */
90 int ind
; /* 0 for init, index when done */
91 int err
; /* Set nonzero for error messages */
92 char *prog
; /* Program name (from @argv[0]@) */
94 /* --- Private variables --- *
96 * Don't play with these, please.
99 char *list
; /* Current short options pointer */
100 int next
; /* Next argument, unpermuted */
101 int order
; /* Ordering of options, flags */
102 char *env
; /* Where we are in the env var */
103 char *estart
; /* Pointer to env var buffer */
107 /*----- Global variables --------------------------------------------------*/
109 extern mdwopt_data mdwopt_global
; /* The default global data */
111 /* --- For compatibility with older programs (and prettiness) --- *
113 * The macros here access the global structure defined above. I consider it
114 * to be perfectly acceptable to use these macros in new code, because it
115 * looks nicer than playing with @mdwopt_global@.
118 #define optarg (mdwopt_global.arg) /* Argument of current option */
119 #define optopt (mdwopt_global.opt) /* Code of current option */
120 #define opterr (mdwopt_global.err) /* Zero to report error messages */
121 #define optind (mdwopt_global.ind) /* Index of first non-option */
122 #define optprog (mdwopt_global.prog) /* Pointer to program name */
124 /*----- Type definitions --------------------------------------------------*/
126 /* --- Long options definition table --- */
129 const char *name
; /* Name of the long option */
130 int has_arg
; /* Does it have an argument? */
131 int *flag
; /* Address of flag variable */
132 int val
; /* Value to store/return */
135 /* --- Old-style names for argument flags in long options table --- */
138 no_argument
, /* No argument required */
139 required_argument
, /* User must specify argument */
140 optional_argument
/* Argument is optional */
143 /* --- New style flag names --- */
146 OPTF_ARGREQ
= 1, /* Required argument */
147 OPTF_ARGOPT
= 2, /* Optional argument */
148 OPTF_SWITCH
= 4, /* OR val into flag, don't store */
149 OPTF_NEGATE
= 8 /* Allow long option to be negated */
153 OPTF_NOLONGS
= 1, /* Don't read long options */
154 OPTF_NOSHORTS
= 2, /* Don't read short options */
155 OPTF_NUMBERS
= 4, /* Read numeric options */
156 OPTF_NEGATION
= 8, /* Allow `%|+|%' for negations */
157 OPTF_ENVVAR
= 16, /* Parse options from env var */
158 OPTF_NOPROGNAME
= 32, /* Don't set @optprog@ */
159 OPTF_NEGNUMBER
= 64 /* Allow negated number options */
163 OPTF_NEGATED
= 256 /* Option flag was negated by user */
166 /* --- Older new-style names --- */
169 gFlag_argReq
= 1, gFlag_argOpt
= 2, gFlag_switch
= 4, gFlag_negate
= 8
173 gFlag_noLongs
= 1, gFlag_noShorts
= 2, gFlag_numbers
= 4,
174 gFlag_negation
= 8, gFlag_envVar
= 16, gFlag_noProgName
= 32,
182 /*----- Main code ---------------------------------------------------------*/
184 /* --- @mdwopt@ --- *
186 * Arguments: @int argc@ = number of command line arguments
187 * @char * const *argv@ = pointer to command line arguments
188 * @const char *shortopt@ = pointer to short options information
189 * @const struct option *longopts@ = pointer to long opts info
190 * @int *longind@ = where to store matched longopt
191 * @mdwopt_data *data@ = persistent state for the parser
192 * @int flags@ = various useful flags
194 * Returns: Value of option found next, or an error character, or
195 * @EOF@ for the last thing.
197 * Use: Reads options. The routine should be more-or-less compatible
198 * with standard getopts, although it provides many more
199 * features even than the standard GNU implementation.
201 * The precise manner of options parsing is determined by
202 * various flag settings, which are described below. By setting
203 * flag values appropriately, you can achieve behaviour very
204 * similar to most other getopt routines.
207 * How options parsing appears to users
209 * A command line consists of a number of `words' (which may
210 * contain spaces, according to various shell quoting
211 * conventions). A word may be an option, an argument to an
212 * option, or a non-option. An option begins with a special
213 * character, usually `%|-|%', although `%|+|%' is also used
214 * sometimes. As special exceptions, the word containing only a
215 * `%|-|%' is considered to be a non-option, since it usually
216 * represents standard input or output as a filename, and the
217 * word containing a double-dash `%|--|%' is used to mark all
218 * following words as being non-options regardless of their
221 * Traditionally, all words after the first non-option have been
222 * considered to be non-options automatically, so that options
223 * must be specified before filenames. However, this
224 * implementation can extract all the options from the command
225 * line regardless of their position. This can usually be
226 * disabled by setting one of the environment variables
227 * `%|POSIXLY_CORRECT|%' or `%|_POSIX_OPTION_ORDER|%'.
229 * There are two different styles of options: `short' and
232 * Short options are the sort which Unix has known for ages: an
233 * option is a single letter, preceded by a `%|-|%'. Short
234 * options can be joined together to save space (and possibly to
235 * make silly words): e.g., instead of giving options
236 * `%|-x.-y|%', a user could write `%|-xy|%'. Some short
237 * options can have arguments, which appear after the option
238 * letter, either immediately following, or in the next `word'
239 * (so an option with an argument could be written as
240 * `%|-o foo|%' or as `%|-ofoo|%'). Note that options with
241 * optional arguments must be written in the second style.
243 * When a short option controls a flag setting, it is sometimes
244 * possible to explicitly turn the flag off, as well as turning
245 * it on, (usually to override default options). This is
246 * usually done by using a `%|+|%' instead of a `%|-|%' to
247 * introduce the option.
249 * Long options, as popularized by the GNU utilities, are given
250 * long-ish memorable names, preceded by a double-dash `%|--|%'.
251 * Since their names are more than a single character, long
252 * options can't be combined in the same way as short options.
253 * Arguments to long options may be given either in the same
254 * `word', separated from the option name by an equals sign, or
255 * in the following `word'.
257 * Long option names can be abbreviated if necessary, as long
258 * as the abbreviation is unique. This means that options can
259 * have sensible and memorable names but still not require much
260 * typing from an experienced user.
262 * Like short options, long options can control flag settings.
263 * The options to manipulate these settings come in pairs: an
264 * option of the form `%|--set-flag|%' might set the flag, while
265 * an option of the form `%|--no-set-flag|%' might clear it.
267 * It is usual for applications to provide both short and long
268 * options with identical behaviour. Some applications with
269 * lots of options may only provide long options (although they
270 * will often be only two or three characters long). In this
271 * case, long options can be preceded with a single `%|-|%'
272 * character, and negated by a `%|+|%' character.
274 * Finally, some (older) programs accept arguments of the form
275 * `%%@.{"-"<number>}%%', to set some numerical parameter,
276 * typically a line count of some kind.
279 * How programs parse options
281 * An application parses its options by calling mdwopt
282 * repeatedly. Each time it is called, mdwopt returns a value
283 * describing the option just read, and stores information about
284 * the option in a data block. The value %$-1$% is returned
285 * when there are no more options to be read. The `%|?|%'
286 * character is returned when an error is encountered.
288 * Before starting to parse options, the value @data->ind@ must
289 * be set to 0 or 1. The value of @data->err@ can also be set,
290 * to choose whether errors are reported by mdwopt.
292 * The program's `@argc@' and `@argv@' arguments are passed to
293 * the options parser, so that it can read the command line. A
294 * flags word is also passed, allowing the program fine control
295 * over parsing. The flags are described above.
297 * Short options are described by a string, which once upon a
298 * time just contained the permitted option characters. Now the
299 * options string begins with a collection of flag characters,
300 * and various flag characters can be put after options
301 * characters to change their properties.
303 * If the first character of the short options string is
304 * `%|+|%', `%|-|%' or `%|!|%', the order in which options are
305 * read is modified, as follows:
307 * `%|+|%' forces the POSIX order to be used. As soon as a non-
308 * option is found, mdwopt returns %$-1$%.
310 * `%|-|%' makes mdwopt treat non-options as being `special'
311 * sorts of option. When a non-option word is found, the
312 * value 0 is returned, and the actual text of the word
313 * is stored as being the option's argument.
315 * `%|!|%' forces the default order to be used. The entire
316 * command line is scanned for options, which are
317 * returned in order. However, during this process,
318 * the options are moved in the @argv@ array, so that
319 * they appear before the non- options.
321 * A `%|:|%' character may be placed after the ordering flag (or
322 * at the very beginning if no ordering flag is given) which
323 * indicates that the character `%|:|%', rather than `%|?|%',
324 * should be returned if a missing argument error is detected.
326 * Each option in the string can be followed by a `%|+|%' sign,
327 * indicating that it can be negated, a `%|:|%' sign indicating
328 * that it requires an argument, or a `%|::|%' string,
329 * indicating an optional argument. Both `%|+|%' and `%|:|%' or
330 * `%|::|%' may be given, although the `%|+|%' must come first.
332 * If an option is found, the option character is returned to
333 * the caller. A pointer to an argument is stored in
334 * @data->arg@, or @NULL@ is stored if there was no argument.
335 * If a negated option was found, the option character is
336 * returned ORred with @gFlag_negated@ (bit 8 set).
338 * Long options are described in a table. Each entry in the
339 * table is of type @struct option@, and the table is terminated
340 * by an entry whose @name@ field is null. Each option has
341 * a flags word which, due to historical reasons, is called
342 * @has_arg@. This describes various properties of the option,
343 * such as what sort of argument it takes, and whether it can
346 * When mdwopt finds a long option, it looks the name up in the
347 * table. The index of the matching entry is stored in the
348 * @longind@ variable, passed to mdwopt (unless @longind@ is 0):
349 * a value of %$-1$% indicates that no long option was
350 * found. The behaviour is then dependent on the values in the
351 * table entry. If @flag@ is nonzero, it points to an integer
352 * to be modified by mdwopt. Usually the value in the @val@
353 * field is simply stored in the @flag@ variable. If the flag
354 * @gFlag_switch@ is set, however, the value is combined with
355 * the existing value of the flags using a bitwise OR. If
356 * @gFlag_negate@ is set, then the flag bit will be cleared if a
357 * matching negated long option is found. The value 0 is
360 * If @flag@ is zero, the value in @val@ is returned by mdwopt,
361 * possibly with bit 8 set if the option was negated.
363 * Arguments for long options are stored in @data->arg@, as
366 * Numeric options, if enabled, cause the value `%|#|%' to be
367 * returned, and the numeric value to be stored in @data->opt@.
369 * If the flag @gFlag_envVar@ is set on entry, options will be
370 * extracted from an environment variable whose name is built by
371 * capitalising all the letters of the program's name. (This
372 * allows a user to have different default settings for a
373 * program, by calling it through different symbolic links.) */
375 extern int mdwopt(int /*argc*/, char *const */
*argv*/
,
376 const char */
*shortopt*/
,
377 const struct option */
*longopts*/
, int */
*longind*/
,
378 mdwopt_data */
*data*/
, int /*flags*/);
380 /* --- Macros for more commonly used routines --- */
382 #define getopt(c, v, o) mdwopt(c, v, o, 0, 0, 0, gFlag_noLongs)
383 #define getopt_long(c, v, o, l, li) mdwopt(c, v, o, l, li, 0, 0)
384 #define getopt_long_only(c, v, o, l, li) \
385 mdwopt(c, v, o, l, li, 0, gFlag_noShorts)
391 /*----- C++ wrapper class -------------------------------------------------*/
395 /* --- Class: @MdwOpt@ --- *
399 * Methods: @MdwOpt@ -- construct a new mdwopt object with the given
400 * arguments. These are remembered for later use.
401 * @arg@ -- return the argument of the current option
402 * arguments. These are remembered for later use.
403 * @arg@ -- return the argument of the current option
404 * @opt@ -- return the value of the current option
405 * @ind@ -- return the index of the next unread argument
406 * @longind@ -- return index of current long option in table
407 * @errors@ -- return or set whether we report errors to the
409 * @prog@ -- return program name from @argv[0]@
410 * @next@ -- return next option read from the table
412 * Use: A simple C++ class for encapsulating the options parser.
413 * The methods are all nice and simple, and extremely similar
414 * to the normal C interface described above.
421 const char *shortopts
;
422 const struct option
*longopts
;
429 MdwOpt(int c
, char * const *v
, const char *so
,
430 const struct option
*lo
, int f
=0) :
431 argc(c
), argv(v
), shortopts(so
), longopts(lo
), flags(f
) {
436 const char *arg(void) const { return (data
.arg
); }
437 int opt(void) const { return (data
.opt
); }
438 int errors(void) const { return (data
.err
); }
439 int errors(int e
) { int oe
= data
.err
; data
.err
= e
; return (oe
); }
440 int ind(void) const { return (data
.ind
); }
441 int longind(void) const { return (long_ind
); }
442 const char *prog(void) const { return (data
.prog
); }
445 return (mdwopt(argc
, argv
, shortopts
,
446 longopts
, &long_ind
, &data
, flags
));
452 /*----- That's all, folks -------------------------------------------------*/