3 * $Id: mdwopt.h,v 1.3 1999/05/14 18:51:42 mdw Exp $
5 * Options parsing, similar to GNU @getopt_long@
7 * (c) 1996 Mark Wooding
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 1.3 1999/05/14 18:51:42 mdw
34 * Reformat the LGPL notice slightly.
36 * Revision 1.2 1999/05/13 22:57:23 mdw
37 * Change `-ise' to `-ize' throughout.
39 * Revision 1.1.1.1 1999/05/05 19:23:47 mdw
40 * New import. The old CVS repository was lost in a disk disaster.
42 * --- Previous lives ---
45 * Revision 1.5 1997/08/09 20:27:59 mdw
46 * Fix spelling of `Licensing'.
48 * Revision 1.4 1997/07/29 21:11:49 mdw
49 * Fixed address of the FSF.
51 * Revision 1.3 1996/12/31 19:41:33 mdw
54 * Revision 1.2 1996/11/23 00:47:25 mdw
55 * Added `MdwOpt' object from the `anagram' source code.
57 * Revision 1.1 1996/09/24 18:01:43 mdw
65 /*----- Options handling structures ---------------------------------------*/
71 /* --- @mdwopt_data@ --- *
73 * Contains all the information needed by the @mdwopt@ routine to do its
78 /* --- Public variables --- */
80 char *arg
; /* Arg of current option, or 0 */
81 int opt
; /* Value of current option */
82 int ind
; /* 0 for init, index when done */
83 int err
; /* Set nonzero for error messages */
84 char *prog
; /* Program name (from @argv[0]@) */
86 /* --- Private variables --- *
88 * Don't play with these, please.
91 char *list
; /* Current short options pointer */
92 int next
; /* Next argument, unpermuted */
93 int order
; /* Ordering of options, flags */
94 char *env
; /* Where we are in the env var */
95 char *estart
; /* Pointer to env var buffer */
99 /*----- Global variables --------------------------------------------------*/
101 extern mdwopt_data mdwopt_global
; /* The default global data */
103 /* --- For compatibility with older programs (and prettiness) --- *
105 * The macros here access the global structure defined above. I consider it
106 * to be perfectly acceptable to use these macros in new code, because it
107 * looks nicer than playing with @mdwopt_global@.
110 #define optarg (mdwopt_global.arg) /* Argument of current option */
111 #define optopt (mdwopt_global.opt) /* Code of current option */
112 #define opterr (mdwopt_global.err) /* Zero to report error messages */
113 #define optind (mdwopt_global.ind) /* Index of first non-option */
114 #define optprog (mdwopt_global.prog) /* Pointer to program name */
116 /*----- Type definitions --------------------------------------------------*/
118 /* --- Long options definition table --- */
121 const char *name
; /* Name of the long option */
122 int has_arg
; /* Does it have an argument? */
123 int *flag
; /* Address of flag variable */
124 int val
; /* Value to store/return */
127 /* --- Old-style names for argument flags in long options table --- */
130 no_argument
, /* No argument required */
131 required_argument
, /* User must specify argument */
132 optional_argument
/* Argument is optional */
135 /* --- New style flag names --- */
138 gFlag_argReq
= 1, /* Required argument */
139 gFlag_argOpt
= 2, /* Optional argument */
140 gFlag_switch
= 4, /* OR val into flag, don't store */
141 gFlag_negate
= 8, /* Allow long option to be negated */
142 gFlag__last_long_opt_flag
= 0 /* Dummy value */
146 gFlag_noLongs
= 1, /* Don't read long options */
147 gFlag_noShorts
= 2, /* Don't read short options */
148 gFlag_numbers
= 4, /* Read numeric options */
149 gFlag_negation
= 8, /* Allow `%|+|%' for negations */
150 gFlag_envVar
= 16, /* Parse options from env var */
151 gFlag_noProgName
= 32, /* Don't set @optprog@ */
152 gFlag_negNumber
= 64, /* Allow negated number options */
153 gFlag__last_mdwopt_flag
= 0 /* Dummy value */
157 gFlag_negated
= 256, /* Option flag was negated by user */
158 gFlag__last_return_flag
= 0 /* Dummy value */
161 /*----- Main code ---------------------------------------------------------*/
163 /* --- @mdwopt@ --- *
165 * Arguments: @int argc@ = number of command line arguments
166 * @char * const *argv@ = pointer to command line arguments
167 * @const char *shortopt@ = pointer to short options information
168 * @const struct option *longopts@ = pointer to long opts info
169 * @int *longind@ = where to store matched longopt
170 * @mdwopt_data *data@ = persistent state for the parser
171 * @int flags@ = various useful flags
173 * Returns: Value of option found next, or an error character, or
174 * @EOF@ for the last thing.
176 * Use: Reads options. The routine should be more-or-less compatible
177 * with standard getopts, although it provides many more
178 * features even than the standard GNU implementation.
180 * The precise manner of options parsing is determined by
181 * various flag settings, which are described below. By setting
182 * flag values appropriately, you can achieve behaviour very
183 * similar to most other getopt routines.
186 * How options parsing appears to users
188 * A command line consists of a number of `words' (which may
189 * contain spaces, according to various shell quoting
190 * conventions). A word may be an option, an argument to an
191 * option, or a non-option. An option begins with a special
192 * character, usually `%|-|%', although `%|+|%' is also used
193 * sometimes. As special exceptions, the word containing only a
194 * `%|-|%' is considered to be a non-option, since it usually
195 * represents standard input or output as a filename, and the
196 * word containing a double-dash `%|--|%' is used to mark all
197 * following words as being non-options regardless of their
200 * Traditionally, all words after the first non-option have been
201 * considered to be non-options automatically, so that options
202 * must be specified before filenames. However, this
203 * implementation can extract all the options from the command
204 * line regardless of their position. This can usually be
205 * disabled by setting one of the environment variables
206 * `%|POSIXLY_CORRECT|%' or `%|_POSIX_OPTION_ORDER|%'.
208 * There are two different styles of options: `short' and
211 * Short options are the sort which Unix has known for ages: an
212 * option is a single letter, preceded by a `%|-|%'. Short
213 * options can be joined together to save space (and possibly to
214 * make silly words): e.g., instead of giving options
215 * `%|-x.-y|%', a user could write `%|-xy|%'. Some short
216 * options can have arguments, which appear after the option
217 * letter, either immediately following, or in the next `word'
218 * (so an option with an argument could be written as
219 * `%|-o foo|%' or as `%|-ofoo|%'). Note that options with
220 * optional arguments must be written in the second style.
222 * When a short option controls a flag setting, it is sometimes
223 * possible to explicitly turn the flag off, as well as turning
224 * it on, (usually to override default options). This is
225 * usually done by using a `%|+|%' instead of a `%|-|%' to
226 * introduce the option.
228 * Long options, as popularized by the GNU utilities, are given
229 * long-ish memorable names, preceded by a double-dash `%|--|%'.
230 * Since their names are more than a single character, long
231 * options can't be combined in the same way as short options.
232 * Arguments to long options may be given either in the same
233 * `word', separated from the option name by an equals sign, or
234 * in the following `word'.
236 * Long option names can be abbreviated if necessary, as long
237 * as the abbreviation is unique. This means that options can
238 * have sensible and memorable names but still not require much
239 * typing from an experienced user.
241 * Like short options, long options can control flag settings.
242 * The options to manipulate these settings come in pairs: an
243 * option of the form `%|--set-flag|%' might set the flag, while
244 * an option of the form `%|--no-set-flag|%' might clear it.
246 * It is usual for applications to provide both short and long
247 * options with identical behaviour. Some applications with
248 * lots of options may only provide long options (although they
249 * will often be only two or three characters long). In this
250 * case, long options can be preceded with a single `%|-|%'
251 * character, and negated by a `%|+|%' character.
253 * Finally, some (older) programs accept arguments of the form
254 * `%%@.{"-"<number>}%%', to set some numerical parameter,
255 * typically a line count of some kind.
258 * How programs parse options
260 * An application parses its options by calling mdwopt
261 * repeatedly. Each time it is called, mdwopt returns a value
262 * describing the option just read, and stores information about
263 * the option in a data block. The value %$-1$% is returned
264 * when there are no more options to be read. The `%|?|%'
265 * character is returned when an error is encountered.
267 * Before starting to parse options, the value @data->ind@ must
268 * be set to 0 or 1. The value of @data->err@ can also be set,
269 * to choose whether errors are reported by mdwopt.
271 * The program's `@argc@' and `@argv@' arguments are passed to
272 * the options parser, so that it can read the command line. A
273 * flags word is also passed, allowing the program fine control
274 * over parsing. The flags are described above.
276 * Short options are described by a string, which once upon a
277 * time just contained the permitted option characters. Now the
278 * options string begins with a collection of flag characters,
279 * and various flag characters can be put after options
280 * characters to change their properties.
282 * If the first character of the short options string is
283 * `%|+|%', `%|-|%' or `%|!|%', the order in which options are
284 * read is modified, as follows:
286 * `%|+|%' forces the POSIX order to be used. As soon as a non-
287 * option is found, mdwopt returns %$-1$%.
289 * `%|-|%' makes mdwopt treat non-options as being `special'
290 * sorts of option. When a non-option word is found, the
291 * value 0 is returned, and the actual text of the word
292 * is stored as being the option's argument.
294 * `%|!|%' forces the default order to be used. The entire
295 * command line is scanned for options, which are
296 * returned in order. However, during this process,
297 * the options are moved in the @argv@ array, so that
298 * they appear before the non- options.
300 * A `%|:|%' character may be placed after the ordering flag (or
301 * at the very beginning if no ordering flag is given) which
302 * indicates that the character `%|:|%', rather than `%|?|%',
303 * should be returned if a missing argument error is detected.
305 * Each option in the string can be followed by a `%|+|%' sign,
306 * indicating that it can be negated, a `%|:|%' sign indicating
307 * that it requires an argument, or a `%|::|%' string,
308 * indicating an optional argument. Both `%|+|%' and `%|:|%' or
309 * `%|::|%' may be given, although the `%|+|%' must come first.
311 * If an option is found, the option character is returned to
312 * the caller. A pointer to an argument is stored in
313 * @data->arg@, or @NULL@ is stored if there was no argument.
314 * If a negated option was found, the option character is
315 * returned ORred with @gFlag_negated@ (bit 8 set).
317 * Long options are described in a table. Each entry in the
318 * table is of type @struct option@, and the table is terminated
319 * by an entry whose @name@ field is null. Each option has
320 * a flags word which, due to historical reasons, is called
321 * @has_arg@. This describes various properties of the option,
322 * such as what sort of argument it takes, and whether it can
325 * When mdwopt finds a long option, it looks the name up in the
326 * table. The index of the matching entry is stored in the
327 * @longind@ variable, passed to mdwopt (unless @longind@ is 0):
328 * a value of %$-1$% indicates that no long option was
329 * found. The behaviour is then dependent on the values in the
330 * table entry. If @flag@ is nonzero, it points to an integer
331 * to be modified by mdwopt. Usually the value in the @val@
332 * field is simply stored in the @flag@ variable. If the flag
333 * @gFlag_switch@ is set, however, the value is combined with
334 * the existing value of the flags using a bitwise OR. If
335 * @gFlag_negate@ is set, then the flag bit will be cleared if a
336 * matching negated long option is found. The value 0 is
339 * If @flag@ is zero, the value in @val@ is returned by mdwopt,
340 * possibly with bit 8 set if the option was negated.
342 * Arguments for long options are stored in @data->arg@, as
345 * Numeric options, if enabled, cause the value `%|#|%' to be
346 * returned, and the numeric value to be stored in @data->opt@.
348 * If the flag @gFlag_envVar@ is set on entry, options will be
349 * extracted from an environment variable whose name is built by
350 * capitalising all the letters of the program's name. (This
351 * allows a user to have different default settings for a
352 * program, by calling it through different symbolic links.) */
354 extern int mdwopt(int /*argc*/, char *const */
*argv*/
,
355 const char */
*shortopt*/
,
356 const struct option */
*longopts*/
, int */
*longind*/
,
357 mdwopt_data */
*data*/
, int /*flags*/);
359 /* --- Macros for more commonly used routines --- */
361 #define getopt(c, v, o) mdwopt(c, v, o, 0, 0, 0, gFlag_noLongs)
362 #define getopt_long(c, v, o, l, li) mdwopt(c, v, o, l, li, 0, 0)
363 #define getopt_long_only(c, v, o, l, li) \
364 mdwopt(c, v, o, l, li, 0, gFlag_noShorts)
370 /*----- C++ wrapper class -------------------------------------------------*/
374 /* --- Class: @MdwOpt@ --- *
378 * Methods: @MdwOpt@ -- construct a new mdwopt object with the given
379 * arguments. These are remembered for later use.
380 * @arg@ -- return the argument of the current option
381 * arguments. These are remembered for later use.
382 * @arg@ -- return the argument of the current option
383 * @opt@ -- return the value of the current option
384 * @ind@ -- return the index of the next unread argument
385 * @longind@ -- return index of current long option in table
386 * @errors@ -- return or set whether we report errors to the
388 * @prog@ -- return program name from @argv[0]@
389 * @next@ -- return next option read from the table
391 * Use: A simple C++ class for encapsulating the options parser.
392 * The methods are all nice and simple, and extremely similar
393 * to the normal C interface described above.
400 const char *shortopts
;
401 const struct option
*longopts
;
408 MdwOpt(int c
, char * const *v
, const char *so
,
409 const struct option
*lo
, int f
=0) :
410 argc(c
), argv(v
), shortopts(so
), longopts(lo
), flags(f
) {
415 const char *arg(void) const { return (data
.arg
); }
416 int opt(void) const { return (data
.opt
); }
417 int errors(void) const { return (data
.err
); }
418 int errors(int e
) { int oe
= data
.err
; data
.err
= e
; return (oe
); }
419 int ind(void) const { return (data
.ind
); }
420 int longind(void) const { return (long_ind
); }
421 const char *prog(void) const { return (data
.prog
); }
424 return (mdwopt(argc
, argv
, shortopts
,
425 longopts
, &long_ind
, &data
, flags
));
431 /*----- That's all, folks -------------------------------------------------*/