3340d90f593031756a6e8d80f5a704ddff6f89a1
[argpar.git] / argpar / argpar.h
1 /*
2 * SPDX-License-Identifier: MIT
3 *
4 * Copyright (c) 2019-2021 Philippe Proulx <pproulx@efficios.com>
5 * Copyright (c) 2020-2021 Simon Marchi <simon.marchi@efficios.com>
6 */
7
8 #ifndef ARGPAR_ARGPAR_H
9 #define ARGPAR_ARGPAR_H
10
11 #include <stdbool.h>
12
13 /*!
14 @mainpage
15
16 See the \ref api module.
17
18 @addtogroup api argpar API
19 @{
20
21 argpar is a library which provides an iterator-based API to parse
22 command-line arguments.
23
24 The argpar parser supports:
25
26 <ul>
27 <li>
28 Short options without an argument, possibly tied together:
29
30 @code{.unparsed}
31 -f -auf -n
32 @endcode
33
34 <li>
35 Short options with arguments:
36
37 @code{.unparsed}
38 -b 45 -f/mein/file -xyzhello
39 @endcode
40
41 <li>
42 Long options without an argument:
43
44 @code{.unparsed}
45 --five-guys --burger-king --pizza-hut --subway
46 @endcode
47
48 <li>
49 Long options with arguments (two original arguments or a single
50 one with a <code>=</code> character):
51
52 @code{.unparsed}
53 --security enable --time=18.56
54 @endcode
55
56 <li>
57 Non-option arguments (anything else, including
58 <code>-</code> and <code>\--</code>).
59
60 A non-option argument cannot have the form of an option, for example
61 if you need to pass the exact relative path
62 <code>\--component</code>. In that case, you would need to pass
63 <code>./\--component</code>. There's no generic way to escape
64 <code>-</code> as of this version.
65 </ul>
66
67 Create a parsing iterator with argpar_iter_create(), then repeatedly
68 call argpar_iter_next() to access the parsing results (items), until one
69 of:
70
71 - There are no more arguments.
72
73 - The argument parser encounters an error (for example, an unknown
74 option).
75
76 - You need to stop.
77
78 argpar_iter_create() accepts duplicate option descriptors in
79 \p descrs (argpar_iter_next() produces one item for each
80 instance).
81
82 A parsing item (the result of argpar_iter_next()) has the type
83 #argpar_item.
84
85 Get the type (option or non-option) of an item with
86 argpar_item_type(). Each item type has its set of dedicated functions
87 (\c argpar_item_opt_ and \c argpar_item_non_opt_ prefixes).
88
89 argpar_iter_next() produces the items in the same order that it parses
90 original arguments, including non-option arguments. This means, for
91 example, that for:
92
93 @code{.unparsed}
94 --hello --count=23 /path/to/file -ab --type file -- magie
95 @endcode
96
97 argpar_iter_next() produces the following items, in this order:
98
99 -# Option item (<code>\--hello</code>).
100 -# Option item (<code>\--count</code> with argument <code>23</code>).
101 -# Non-option item (<code>/path/to/file</code>).
102 -# Option item (<code>-a</code>).
103 -# Option item (<code>-b</code>).
104 -# Option item (<code>\--type</code> with argument <code>file</code>).
105 -# Non-option item (<code>\--</code>).
106 -# Non-option item (<code>magie</code>).
107 */
108
109 /*
110 * If argpar is used in some shared library, we don't want said library
111 * to export its symbols, so mark them as "hidden".
112 *
113 * On Windows, symbols are local unless explicitly exported; see
114 * <https://gcc.gnu.org/wiki/Visibility>.
115 */
116 #if defined(_WIN32) || defined(__CYGWIN__)
117 # define ARGPAR_HIDDEN
118 #else
119 # define ARGPAR_HIDDEN __attribute__((visibility("hidden")))
120 #endif
121
122 struct argpar_opt_descr;
123
124 /*!
125 @name Item API
126 @{
127 */
128
129 /*!
130 @brief
131 Type of a parsing item, as returned by argpar_item_type().
132 */
133 enum argpar_item_type {
134 /// Option
135 ARGPAR_ITEM_TYPE_OPT,
136
137 /// Non-option
138 ARGPAR_ITEM_TYPE_NON_OPT,
139 };
140
141 /*!
142 @struct argpar_item
143
144 @brief
145 Opaque parsing item type
146
147 argpar_iter_next() sets a pointer to such a type.
148 */
149 struct argpar_item;
150
151 /*!
152 @brief
153 Returns the type of the parsing item \p item.
154
155 @param[in] item
156 Parsing item of which to get the type.
157
158 @returns
159 Type of \p item.
160
161 @pre
162 \p item is not \c NULL.
163 */
164 /// @cond hidden_macro
165 ARGPAR_HIDDEN
166 /// @endcond
167 enum argpar_item_type argpar_item_type(const struct argpar_item *item);
168
169 /*!
170 @brief
171 Returns the option descriptor of the option parsing item \p item.
172
173 @param[in] item
174 Option parsing item of which to get the option descriptor.
175
176 @returns
177 Option descriptor of \p item.
178
179 @pre
180 \p item is not \c NULL.
181 @pre
182 \p item has the type #ARGPAR_ITEM_TYPE_OPT.
183 */
184 /// @cond hidden_macro
185 ARGPAR_HIDDEN
186 /// @endcond
187 const struct argpar_opt_descr *argpar_item_opt_descr(
188 const struct argpar_item *item);
189
190 /*!
191 @brief
192 Returns the argument of the option parsing item \p item, or
193 \c NULL if none.
194
195 @param[in] item
196 Option parsing item of which to get the argument.
197
198 @returns
199 Argument of \p item, or \c NULL if none.
200
201 @pre
202 \p item is not \c NULL.
203 @pre
204 \p item has the type #ARGPAR_ITEM_TYPE_OPT.
205 */
206 /// @cond hidden_macro
207 ARGPAR_HIDDEN
208 /// @endcond
209 const char *argpar_item_opt_arg(const struct argpar_item *item);
210
211 /*!
212 @brief
213 Returns the complete original argument, pointing to one of the
214 entries of the original arguments (in \p argv, as passed to
215 argpar_iter_create()), of the non-option parsing item \p item.
216
217 @param[in] item
218 Non-option parsing item of which to get the complete original
219 argument.
220
221 @returns
222 Complete original argument of \p item.
223
224 @pre
225 \p item is not \c NULL.
226 @pre
227 \p item has the type #ARGPAR_ITEM_TYPE_NON_OPT.
228 */
229 /// @cond hidden_macro
230 ARGPAR_HIDDEN
231 /// @endcond
232 const char *argpar_item_non_opt_arg(const struct argpar_item *item);
233
234 /*!
235 @brief
236 Returns the index, within \em all the original arguments (in
237 \p argv, as passed to argpar_iter_create()), of the non-option
238 parsing item \p item.
239
240 For example, with the following command line (all options have no
241 argument):
242
243 @code{.unparsed}
244 -f -m meow --jus mix --kilo
245 @endcode
246
247 The original argument index of \c meow is&nbsp;2 while the original
248 argument index of \c mix is&nbsp;4.
249
250 @param[in] item
251 Non-option parsing item of which to get the original argument index.
252
253 @returns
254 Original argument index of \p item.
255
256 @pre
257 \p item is not \c NULL.
258 @pre
259 \p item has the type #ARGPAR_ITEM_TYPE_NON_OPT.
260
261 @sa
262 argpar_item_non_opt_non_opt_index() -- Returns the non-option index
263 of a non-option parsing item.
264 */
265 /// @cond hidden_macro
266 ARGPAR_HIDDEN
267 /// @endcond
268 unsigned int argpar_item_non_opt_orig_index(const struct argpar_item *item);
269
270 /*!
271 @brief
272 Returns the index, within the parsed non-option parsing items, of
273 the non-option parsing item \p item.
274
275 For example, with the following command line (all options have no
276 argument):
277
278 @code{.unparsed}
279 -f -m meow --jus mix --kilo
280 @endcode
281
282 The non-option index of \c meow is&nbsp;0 while the original
283 argument index of \c mix is&nbsp;1.
284
285 @param[in] item
286 Non-option parsing item of which to get the non-option index.
287
288 @returns
289 Non-option index of \p item.
290
291 @pre
292 \p item is not \c NULL.
293 @pre
294 \p item has the type #ARGPAR_ITEM_TYPE_NON_OPT.
295
296 @sa
297 argpar_item_non_opt_orig_index() -- Returns the original argument
298 index of a non-option parsing item.
299 */
300 /// @cond hidden_macro
301 ARGPAR_HIDDEN
302 /// @endcond
303 unsigned int argpar_item_non_opt_non_opt_index(const struct argpar_item *item);
304
305 /*!
306 @brief
307 Destroys the parsing item \p item.
308
309 @param[in] item
310 Parsing item to destroy (may be \c NULL).
311 */
312 /// @cond hidden_macro
313 ARGPAR_HIDDEN
314 /// @endcond
315 void argpar_item_destroy(const struct argpar_item *item);
316
317 /*!
318 @def ARGPAR_ITEM_DESTROY_AND_RESET(_item)
319
320 @brief
321 Calls argpar_item_destroy() with \p _item, and then sets \p _item
322 to \c NULL.
323
324 @param[in] _item
325 Item to destroy and variable to reset
326 (<code>const struct argpar_item *</code> type).
327 */
328 #define ARGPAR_ITEM_DESTROY_AND_RESET(_item) \
329 { \
330 argpar_item_destroy(_item); \
331 _item = NULL; \
332 }
333
334 /// @}
335
336 /*!
337 @name Error API
338 @{
339 */
340
341 /*!
342 @struct argpar_error
343
344 @brief
345 Opaque parsing error type
346 */
347 struct argpar_error;
348
349 /*!
350 @brief
351 Returns the index of the original argument (in \p argv, as passed to
352 argpar_iter_create()) for which the parsing error described by
353 \p error occurred.
354
355 @param[in] error
356 Parsing error of which to get the original argument index.
357
358 @returns
359 Original argument index of \p error.
360
361 @pre
362 \p error is not \c NULL.
363 */
364 /// @cond hidden_macro
365 ARGPAR_HIDDEN
366 /// @endcond
367 unsigned int argpar_error_orig_index(const struct argpar_error *error);
368
369 /*!
370 @brief
371 Returns the name of the unknown option for which the parsing error
372 described by \p error occurred.
373
374 The returned name includes any <code>-</code> or <code>\--</code>
375 prefix.
376
377 With the long option with argument form, for example
378 <code>\--mireille=deyglun</code>, this function only returns the name
379 part (<code>\--mireille</code> in the last example).
380
381 You may only call this function if the call to argpar_iter_next() which
382 set \p error returned #ARGPAR_ITER_NEXT_STATUS_ERROR_UNKNOWN_OPT.
383
384 @param[in] error
385 Parsing error of which to get the name of the unknown option.
386
387 @returns
388 Name of the unknown option of \p error.
389
390 @pre
391 \p error is not \c NULL.
392 @pre
393 The call to argpar_iter_next() which set \p error returned
394 #ARGPAR_ITER_NEXT_STATUS_ERROR_UNKNOWN_OPT.
395 */
396 /// @cond hidden_macro
397 ARGPAR_HIDDEN
398 /// @endcond
399 const char *argpar_error_unknown_opt_name(const struct argpar_error *error);
400
401 /*!
402 @brief
403 Returns the descriptor of the option for which the parsing error
404 described by \p error occurred.
405
406 You may only call this function if the call to argpar_iter_next() which
407 set \p error returned #ARGPAR_ITER_NEXT_STATUS_ERROR_MISSING_OPT_ARG or
408 #ARGPAR_ITER_NEXT_STATUS_ERROR_UNEXPECTED_OPG_ARG.
409
410 @param[in] error
411 Parsing error of which to get the option descriptor.
412 @param[out] is_short
413 @parblock
414 If not \c NULL, this function sets \p *is_short to:
415
416 - \c true if the option for which \p error occurred is a short
417 option.
418
419 - \c false if the option for which \p error occurred is a long
420 option.
421 @endparblock
422
423 @returns
424 Descriptor of the option of \p error.
425
426 @pre
427 \p error is not \c NULL.
428 @pre
429 The call to argpar_iter_next() which set \p error returned
430 #ARGPAR_ITER_NEXT_STATUS_ERROR_MISSING_OPT_ARG or
431 #ARGPAR_ITER_NEXT_STATUS_ERROR_UNEXPECTED_OPG_ARG.
432 */
433 /// @cond hidden_macro
434 ARGPAR_HIDDEN
435 /// @endcond
436 const struct argpar_opt_descr *argpar_error_opt_descr(
437 const struct argpar_error *error, bool *is_short);
438
439 /*!
440 @brief
441 Destroys the parsing error \p error.
442
443 @param[in] error
444 Parsing error to destroy (may be \c NULL).
445 */
446 /// @cond hidden_macro
447 ARGPAR_HIDDEN
448 /// @endcond
449 void argpar_error_destroy(const struct argpar_error *error);
450
451 /// @}
452
453 /*!
454 @name Iterator API
455 @{
456 */
457
458 /*!
459 @brief
460 Option descriptor
461
462 argpar_iter_create() accepts an array of instances of such a type,
463 terminated with #ARGPAR_OPT_DESCR_SENTINEL, as its \p descrs parameter.
464
465 The typical usage is, for example:
466
467 @code
468 const struct argpar_opt_descr descrs[] = {
469 { 0, 'd', NULL, false },
470 { 1, '\0', "squeeze", true },
471 { 2, 'm', "meow", true },
472 ARGPAR_OPT_DESCR_SENTINEL,
473 };
474 @endcode
475 */
476 struct argpar_opt_descr {
477 /// Numeric ID, to uniquely identify this descriptor
478 const int id;
479
480 /// Short option character, or <code>'\0'</code>
481 const char short_name;
482
483 /// Long option name (without the <code>\--</code> prefix), or \c NULL
484 const char * const long_name;
485
486 /// \c true if this option has an argument
487 const bool with_arg;
488 };
489
490 /*!
491 @brief
492 Sentinel for an option descriptor array
493
494 The typical usage is, for example:
495
496 @code
497 const struct argpar_opt_descr descrs[] = {
498 { 0, 'd', NULL, false },
499 { 1, '\0', "squeeze", true },
500 { 2, 'm', "meow", true },
501 ARGPAR_OPT_DESCR_SENTINEL,
502 };
503 @endcode
504 */
505 #define ARGPAR_OPT_DESCR_SENTINEL { -1, '\0', NULL, false }
506
507 /*!
508 @struct argpar_iter
509
510 @brief
511 Opaque argpar iterator type
512
513 argpar_iter_create() returns a pointer to such a type.
514 */
515 struct argpar_iter;
516
517 /*!
518 @brief
519 Creates and returns an argument parsing iterator to parse the
520 original arguments \p argv of which the count is \p argc using the
521 option descriptors \p descrs.
522
523 This function initializes the returned structure, but doesn't actually
524 start parsing the arguments.
525
526 argpar considers \em all the elements of \p argv, including the first
527 one, so that you would typically pass <code>(argc - 1)</code> as \p argc
528 and <code>\&argv[1]</code> as \p argv from what <code>main()</code>
529 receives, or ignore the parsing item of the first call to
530 argpar_iter_next().
531
532 \p *argv and \p *descrs must \em not change for all of:
533
534 - The lifetime of the returned iterator (until you call
535 argpar_iter_destroy()).
536
537 - The lifetime of any parsing item (until you call
538 argpar_item_destroy()) which argpar_iter_next() creates from the
539 returned iterator.
540
541 - The lifetime of any parsing error (until you call
542 argpar_error_destroy()) which argpar_iter_next() creates from the
543 returned iterator.
544
545 @param[in] argc
546 Number of original arguments to parse in \p argv.
547 @param[in] argv
548 Original arguments to parse, of which the count is \p argc.
549 @param[in] descrs
550 @parblock
551 Option descriptor array, terminated with #ARGPAR_OPT_DESCR_SENTINEL.
552
553 May contain duplicate entries.
554 @endparblock
555
556 @returns
557 New argument parsing iterator, or \c NULL on memory error.
558
559 @pre
560 \p argc is greater than 0.
561 @pre
562 \p argv is not \c NULL.
563 @pre
564 The first \p argc elements of \p argv are not \c NULL.
565 @pre
566 \p descrs is not \c NULL.
567
568 @sa
569 argpar_iter_destroy() -- Destroys an argument parsing iterator.
570 */
571 /// @cond hidden_macro
572 ARGPAR_HIDDEN
573 /// @endcond
574 struct argpar_iter *argpar_iter_create(unsigned int argc,
575 const char * const *argv,
576 const struct argpar_opt_descr *descrs);
577
578 /*!
579 @brief
580 Destroys the argument parsing iterator \p iter.
581
582 @param[in] iter
583 Argument parsing iterator to destroy (may be \c NULL).
584
585 @sa
586 argpar_iter_create() -- Creates an argument parsing iterator.
587 */
588 /// @cond hidden_macro
589 ARGPAR_HIDDEN
590 /// @endcond
591 void argpar_iter_destroy(struct argpar_iter *iter);
592
593 /*!
594 @brief
595 Return type of argpar_iter_next().
596
597 Error status enumerators have a negative value.
598 */
599 enum argpar_iter_next_status {
600 /// Success
601 ARGPAR_ITER_NEXT_STATUS_OK,
602
603 /// End of iteration (no more original arguments to parse)
604 ARGPAR_ITER_NEXT_STATUS_END,
605
606 /// Unknown option error
607 ARGPAR_ITER_NEXT_STATUS_ERROR_UNKNOWN_OPT = -1,
608
609 /// Missing option argument error
610 ARGPAR_ITER_NEXT_STATUS_ERROR_MISSING_OPT_ARG = -2,
611
612 /// Unexpected option argument error
613 ARGPAR_ITER_NEXT_STATUS_ERROR_UNEXPECTED_OPT_ARG = -3,
614
615 /// Memory error
616 ARGPAR_ITER_NEXT_STATUS_ERROR_MEMORY = -12,
617 };
618
619 /*!
620 @brief
621 Sets \p *item to the next item of the argument parsing iterator
622 \p iter and advances \p iter.
623
624 If there are no more original arguments to parse, this function returns
625 #ARGPAR_ITER_NEXT_STATUS_END.
626
627 @param[in] iter
628 Argument parsing iterator from which to get the next parsing item.
629 @param[out] item
630 @parblock
631 On success, \p *item is the next parsing item of \p iter.
632
633 Destroy \p *item with argpar_item_destroy().
634 @endparblock
635 @param[out] error
636 @parblock
637 When this function returns
638 #ARGPAR_ITER_NEXT_STATUS_ERROR_UNKNOWN_OPT,
639 #ARGPAR_ITER_NEXT_STATUS_ERROR_MISSING_OPT_ARG, or
640 #ARGPAR_ITER_NEXT_STATUS_ERROR_UNEXPECTED_OPG_ARG, if this parameter
641 is not \c NULL,
642 \p *error contains details about the error.
643
644 Destroy \p *error with argpar_error_destroy().
645 @endparblock
646
647 @returns
648 Status code.
649
650 @pre
651 \p iter is not \c NULL.
652 @pre
653 \p item is not \c NULL.
654 */
655 /// @cond hidden_macro
656 ARGPAR_HIDDEN
657 /// @endcond
658 enum argpar_iter_next_status argpar_iter_next(
659 struct argpar_iter *iter, const struct argpar_item **item,
660 const struct argpar_error **error);
661
662 /*
663 * Returns the number of ingested elements from `argv`, as passed to
664 * argpar_iter_create() to create `*iter`, that were required to produce
665 * the previously returned items.
666 */
667
668 /*!
669 @brief
670 Returns the number of ingested original arguments (in
671 \p argv, as passed to argpar_iter_create() to create \p iter) that
672 the parser ingested to produce the \em previous parsing items.
673
674 @param[in] iter
675 Argument parsing iterator of which to get the number of ingested
676 original arguments.
677
678 @returns
679 Number of original arguments which \p iter ingested.
680
681 @pre
682 \p iter is not \c NULL.
683 */
684 /// @cond hidden_macro
685 ARGPAR_HIDDEN
686 /// @endcond
687 unsigned int argpar_iter_ingested_orig_args(const struct argpar_iter *iter);
688
689 /// @}
690
691 /// @}
692
693 #endif /* ARGPAR_ARGPAR_H */
This page took 0.068461 seconds and 4 git commands to generate.