argpar/argpar.c

   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 #include <assert.h>
   9 #include <stdarg.h>
  10 #include <stdbool.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14
  15 #include "argpar.h"
  16
  17 #define ARGPAR_REALLOC(_ptr, _type, _nmemb)                             \
  18         ((_type *) realloc(_ptr, (_nmemb) * sizeof(_type)))
  19
  20 #define ARGPAR_CALLOC(_type, _nmemb)                                    \
  21         ((_type *) calloc((_nmemb), sizeof(_type)))
  22
  23 #define ARGPAR_ZALLOC(_type) ARGPAR_CALLOC(_type, 1)
  24
  25 #define ARGPAR_ASSERT(_cond) assert(_cond)
  26
  27 #ifdef __MINGW_PRINTF_FORMAT
  28 # define ARGPAR_PRINTF_FORMAT __MINGW_PRINTF_FORMAT
  29 #else
  30 # define ARGPAR_PRINTF_FORMAT printf
  31 #endif
  32
  33 /*
  34  * An argpar iterator.
  35  *
  36  * Such a structure contains the state of an iterator between
  37  * calls to argpar_iter_parse_next().
  38  */
  39 struct argpar_iter {
  40         /*
  41          * Data provided by the user to argpar_iter_create(); immutable
  42          * afterwards.
  43          */
  44         unsigned int argc;
  45         const char * const *argv;
  46         const struct argpar_opt_descr *descrs;
  47
  48         /*
  49          * Index of the argument to process in the next
  50          * argpar_iter_parse_next() call.
  51          */
  52         unsigned int i;
  53
  54         /* Counter of non-option arguments */
  55         int non_opt_index;
  56
  57         /*
  58          * Current character of the current short option group: if it's
  59          * not `NULL`, the parser is in within a short option group,
  60          * therefore it must resume there in the next
  61          * argpar_iter_parse_next() call.
  62          */
  63         const char *short_opt_ch;
  64 };
  65
  66 /* Base parsing item */
  67 struct argpar_item {
  68         enum argpar_item_type type;
  69 };
  70
  71 /* Option parsing item */
  72 struct argpar_item_opt {
  73         struct argpar_item base;
  74
  75         /* Corresponding descriptor */
  76         const struct argpar_opt_descr *descr;
  77
  78         /* Argument, or `NULL` if none; owned by this */
  79         char *arg;
  80 };
  81
  82 /* Non-option parsing item */
  83 struct argpar_item_non_opt {
  84         struct argpar_item base;
  85
  86         /*
  87          * Complete argument, pointing to one of the entries of the
  88          * original arguments (`argv`).
  89          */
  90         const char *arg;
  91
  92         /*
  93          * Index of this argument amongst all original arguments
  94          * (`argv`).
  95          */
  96         unsigned int orig_index;
  97
  98         /* Index of this argument amongst other non-option arguments */
  99         unsigned int non_opt_index;
 100 };
 101
 102 static __attribute__((format(ARGPAR_PRINTF_FORMAT, 1, 0)))
 103 char *argpar_vasprintf(const char * const fmt, va_list args)
 104 {
 105         int len1, len2;
 106         char *str;
 107         va_list args2;
 108
 109         va_copy(args2, args);
 110         len1 = vsnprintf(NULL, 0, fmt, args);
 111         if (len1 < 0) {
 112                 str = NULL;
 113                 goto end;
 114         }
 115
 116         str = malloc(len1 + 1);
 117         if (!str) {
 118                 goto end;
 119         }
 120
 121         len2 = vsnprintf(str, len1 + 1, fmt, args2);
 122         ARGPAR_ASSERT(len1 == len2);
 123
 124 end:
 125         va_end(args2);
 126         return str;
 127 }
 128
 129
 130 static __attribute__((format(ARGPAR_PRINTF_FORMAT, 1, 2)))
 131 char *argpar_asprintf(const char * const fmt, ...)
 132 {
 133         va_list args;
 134         char *str;
 135
 136         va_start(args, fmt);
 137         str = argpar_vasprintf(fmt, args);
 138         va_end(args);
 139         return str;
 140 }
 141
 142 static __attribute__((format(ARGPAR_PRINTF_FORMAT, 2, 3)))
 143 bool try_append_string_printf(char ** const str, const char *fmt, ...)
 144 {
 145         char *new_str = NULL;
 146         char *addendum = NULL;
 147         bool success;
 148         va_list args;
 149
 150         if (!str) {
 151                 success = true;
 152                 goto end;
 153         }
 154
 155         ARGPAR_ASSERT(str);
 156         va_start(args, fmt);
 157         addendum = argpar_vasprintf(fmt, args);
 158         va_end(args);
 159
 160         if (!addendum) {
 161                 success = false;
 162                 goto end;
 163         }
 164
 165         new_str = argpar_asprintf("%s%s", *str ? *str : "", addendum);
 166         if (!new_str) {
 167                 success = false;
 168                 goto end;
 169         }
 170
 171         free(*str);
 172         *str = new_str;
 173         success = true;
 174
 175 end:
 176         free(addendum);
 177         return success;
 178 }
 179
 180 ARGPAR_HIDDEN
 181 enum argpar_item_type argpar_item_type(const struct argpar_item * const item)
 182 {
 183         ARGPAR_ASSERT(item);
 184         return item->type;
 185 }
 186
 187 ARGPAR_HIDDEN
 188 const struct argpar_opt_descr *argpar_item_opt_descr(
 189                 const struct argpar_item * const item)
 190 {
 191         ARGPAR_ASSERT(item);
 192         ARGPAR_ASSERT(item->type == ARGPAR_ITEM_TYPE_OPT);
 193         return ((const struct argpar_item_opt *) item)->descr;
 194 }
 195
 196 ARGPAR_HIDDEN
 197 const char *argpar_item_opt_arg(const struct argpar_item * const item)
 198 {
 199         ARGPAR_ASSERT(item);
 200         ARGPAR_ASSERT(item->type == ARGPAR_ITEM_TYPE_OPT);
 201         return ((const struct argpar_item_opt *) item)->arg;
 202 }
 203
 204 ARGPAR_HIDDEN
 205 const char *argpar_item_non_opt_arg(const struct argpar_item * const item)
 206 {
 207         ARGPAR_ASSERT(item);
 208         ARGPAR_ASSERT(item->type == ARGPAR_ITEM_TYPE_NON_OPT);
 209         return ((const struct argpar_item_non_opt *) item)->arg;
 210 }
 211
 212 ARGPAR_HIDDEN
 213 unsigned int argpar_item_non_opt_orig_index(
 214                 const struct argpar_item * const item)
 215 {
 216         ARGPAR_ASSERT(item);
 217         ARGPAR_ASSERT(item->type == ARGPAR_ITEM_TYPE_NON_OPT);
 218         return ((const struct argpar_item_non_opt *) item)->orig_index;
 219 }
 220
 221 ARGPAR_HIDDEN
 222 unsigned int argpar_item_non_opt_non_opt_index(
 223                 const struct argpar_item * const item)
 224 {
 225         ARGPAR_ASSERT(item);
 226         ARGPAR_ASSERT(item->type == ARGPAR_ITEM_TYPE_NON_OPT);
 227         return ((const struct argpar_item_non_opt *) item)->non_opt_index;
 228 }
 229
 230 ARGPAR_HIDDEN
 231 void argpar_item_destroy(const struct argpar_item * const item)
 232 {
 233         if (!item) {
 234                 goto end;
 235         }
 236
 237         if (item->type == ARGPAR_ITEM_TYPE_OPT) {
 238                 struct argpar_item_opt * const opt_item =
 239                         (struct argpar_item_opt *) item;
 240
 241                 free(opt_item->arg);
 242         }
 243
 244         free((void *) item);
 245
 246 end:
 247         return;
 248 }
 249
 250 static
 251 bool push_item(struct argpar_item_array * const array,
 252                 const struct argpar_item * const item)
 253 {
 254         bool success;
 255
 256         ARGPAR_ASSERT(array);
 257         ARGPAR_ASSERT(item);
 258
 259         if (array->n_items == array->n_alloc) {
 260                 const unsigned int new_n_alloc = array->n_alloc * 2;
 261                 const struct argpar_item ** const new_items =
 262                         ARGPAR_REALLOC(array->items, const struct argpar_item *,
 263                                 new_n_alloc);
 264                 if (!new_items) {
 265                         success = false;
 266                         goto end;
 267                 }
 268
 269                 array->n_alloc = new_n_alloc;
 270                 array->items = new_items;
 271         }
 272
 273         array->items[array->n_items] = item;
 274         array->n_items++;
 275         success = true;
 276
 277 end:
 278         return success;
 279 }
 280
 281 static
 282 void destroy_item_array(struct argpar_item_array * const array)
 283 {
 284         if (array) {
 285                 unsigned int i;
 286
 287                 for (i = 0; i < array->n_items; i++) {
 288                         argpar_item_destroy(array->items[i]);
 289                 }
 290
 291                 free(array->items);
 292                 free(array);
 293         }
 294 }
 295
 296 static
 297 struct argpar_item_array *create_item_array(void)
 298 {
 299         struct argpar_item_array *ret;
 300         const int initial_size = 10;
 301
 302         ret = ARGPAR_ZALLOC(struct argpar_item_array);
 303         if (!ret) {
 304                 goto end;
 305         }
 306
 307         ret->items = ARGPAR_CALLOC(const struct argpar_item *, initial_size);
 308         if (!ret->items) {
 309                 goto error;
 310         }
 311
 312         ret->n_alloc = initial_size;
 313         goto end;
 314
 315 error:
 316         destroy_item_array(ret);
 317         ret = NULL;
 318
 319 end:
 320         return ret;
 321 }
 322
 323 static
 324 struct argpar_item_opt *create_opt_item(
 325                 const struct argpar_opt_descr * const descr,
 326                 const char * const arg)
 327 {
 328         struct argpar_item_opt *opt_item =
 329                 ARGPAR_ZALLOC(struct argpar_item_opt);
 330
 331         if (!opt_item) {
 332                 goto end;
 333         }
 334
 335         opt_item->base.type = ARGPAR_ITEM_TYPE_OPT;
 336         opt_item->descr = descr;
 337
 338         if (arg) {
 339                 opt_item->arg = strdup(arg);
 340                 if (!opt_item->arg) {
 341                         goto error;
 342                 }
 343         }
 344
 345         goto end;
 346
 347 error:
 348         argpar_item_destroy(&opt_item->base);
 349         opt_item = NULL;
 350
 351 end:
 352         return opt_item;
 353 }
 354
 355 static
 356 struct argpar_item_non_opt *create_non_opt_item(const char * const arg,
 357                 const unsigned int orig_index,
 358                 const unsigned int non_opt_index)
 359 {
 360         struct argpar_item_non_opt * const non_opt_item =
 361                 ARGPAR_ZALLOC(struct argpar_item_non_opt);
 362
 363         if (!non_opt_item) {
 364                 goto end;
 365         }
 366
 367         non_opt_item->base.type = ARGPAR_ITEM_TYPE_NON_OPT;
 368         non_opt_item->arg = arg;
 369         non_opt_item->orig_index = orig_index;
 370         non_opt_item->non_opt_index = non_opt_index;
 371
 372 end:
 373         return non_opt_item;
 374 }
 375
 376 static
 377 const struct argpar_opt_descr *find_descr(
 378                 const struct argpar_opt_descr * const descrs,
 379                 const char short_name, const char * const long_name)
 380 {
 381         const struct argpar_opt_descr *descr;
 382
 383         for (descr = descrs; descr->short_name || descr->long_name; descr++) {
 384                 if (short_name && descr->short_name &&
 385                                 short_name == descr->short_name) {
 386                         goto end;
 387                 }
 388
 389                 if (long_name && descr->long_name &&
 390                                 strcmp(long_name, descr->long_name) == 0) {
 391                         goto end;
 392                 }
 393         }
 394
 395 end:
 396         return !descr->short_name && !descr->long_name ? NULL : descr;
 397 }
 398
 399 enum parse_orig_arg_opt_ret {
 400         PARSE_ORIG_ARG_OPT_RET_OK,
 401         PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT = -1,
 402         PARSE_ORIG_ARG_OPT_RET_ERROR_MISSING_OPT_ARG = -2,
 403         PARSE_ORIG_ARG_OPT_RET_ERROR_INVALID_OPT = -3,
 404         PARSE_ORIG_ARG_OPT_RET_ERROR_UNEXPECTED_OPT_ARG = -4,
 405         PARSE_ORIG_ARG_OPT_RET_ERROR_MEMORY = -5,
 406 };
 407
 408 static
 409 enum parse_orig_arg_opt_ret parse_short_opts(const char * const short_opts,
 410                 const char * const next_orig_arg,
 411                 const struct argpar_opt_descr * const descrs,
 412                 struct argpar_iter * const iter,
 413                 char ** const error, struct argpar_item ** const item)
 414 {
 415         enum parse_orig_arg_opt_ret ret = PARSE_ORIG_ARG_OPT_RET_OK;
 416         bool used_next_orig_arg = false;
 417         const char *opt_arg = NULL;
 418         const struct argpar_opt_descr *descr;
 419         struct argpar_item_opt *opt_item;
 420
 421         if (strlen(short_opts) == 0) {
 422                 try_append_string_printf(error, "Invalid argument");
 423                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_INVALID_OPT;
 424                 goto error;
 425         }
 426
 427         if (!iter->short_opt_ch) {
 428                 iter->short_opt_ch = short_opts;
 429         }
 430
 431         /* Find corresponding option descriptor */
 432         descr = find_descr(descrs, *iter->short_opt_ch, NULL);
 433         if (!descr) {
 434                 try_append_string_printf(error, "Unknown option `-%c`",
 435                         *iter->short_opt_ch);
 436                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT;
 437                 goto error;
 438         }
 439
 440         if (descr->with_arg) {
 441                 if (iter->short_opt_ch[1]) {
 442                         /* `-oarg` form */
 443                         opt_arg = &iter->short_opt_ch[1];
 444                 } else {
 445                         /* `-o arg` form */
 446                         opt_arg = next_orig_arg;
 447                         used_next_orig_arg = true;
 448                 }
 449
 450                 /*
 451                  * We accept `-o ''` (empty option argument), but not
 452                  * `-o` alone if an option argument is expected.
 453                  */
 454                 if (!opt_arg || (iter->short_opt_ch[1] &&
 455                                 strlen(opt_arg) == 0)) {
 456                         try_append_string_printf(error,
 457                                 "Missing required argument for option `-%c`",
 458                                 *iter->short_opt_ch);
 459                         used_next_orig_arg = false;
 460                         ret = PARSE_ORIG_ARG_OPT_RET_ERROR_MISSING_OPT_ARG;
 461                         goto error;
 462                 }
 463         }
 464
 465         /* Create and append option argument */
 466         opt_item = create_opt_item(descr, opt_arg);
 467         if (!opt_item) {
 468                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_MEMORY;
 469                 goto error;
 470         }
 471
 472         *item = &opt_item->base;
 473         iter->short_opt_ch++;
 474
 475         if (descr->with_arg || !*iter->short_opt_ch) {
 476                 /* Option has an argument: no more options */
 477                 iter->short_opt_ch = NULL;
 478
 479                 if (used_next_orig_arg) {
 480                         iter->i += 2;
 481                 } else {
 482                         iter->i++;
 483                 }
 484         }
 485
 486         goto end;
 487
 488 error:
 489         ARGPAR_ASSERT(ret != PARSE_ORIG_ARG_OPT_RET_OK);
 490
 491 end:
 492         return ret;
 493 }
 494
 495 static
 496 enum parse_orig_arg_opt_ret parse_long_opt(const char * const long_opt_arg,
 497                 const char * const next_orig_arg,
 498                 const struct argpar_opt_descr * const descrs,
 499                 struct argpar_iter * const iter,
 500                 char ** const error, struct argpar_item ** const item)
 501 {
 502         const size_t max_len = 127;
 503         enum parse_orig_arg_opt_ret ret = PARSE_ORIG_ARG_OPT_RET_OK;
 504         const struct argpar_opt_descr *descr;
 505         struct argpar_item_opt *opt_item;
 506         bool used_next_orig_arg = false;
 507
 508         /* Option's argument, if any */
 509         const char *opt_arg = NULL;
 510
 511         /* Position of first `=`, if any */
 512         const char *eq_pos;
 513
 514         /* Buffer holding option name when `long_opt_arg` contains `=` */
 515         char buf[max_len + 1];
 516
 517         /* Option name */
 518         const char *long_opt_name = long_opt_arg;
 519
 520         if (strlen(long_opt_arg) == 0) {
 521                 try_append_string_printf(error, "Invalid argument");
 522                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_INVALID_OPT;
 523                 goto error;
 524         }
 525
 526         /* Find the first `=` in original argument */
 527         eq_pos = strchr(long_opt_arg, '=');
 528         if (eq_pos) {
 529                 const size_t long_opt_name_size = eq_pos - long_opt_arg;
 530
 531                 /* Isolate the option name */
 532                 if (long_opt_name_size > max_len) {
 533                         try_append_string_printf(error,
 534                                 "Invalid argument `--%s`", long_opt_arg);
 535                         ret = PARSE_ORIG_ARG_OPT_RET_ERROR_INVALID_OPT;
 536                         goto error;
 537                 }
 538
 539                 memcpy(buf, long_opt_arg, long_opt_name_size);
 540                 buf[long_opt_name_size] = '\0';
 541                 long_opt_name = buf;
 542         }
 543
 544         /* Find corresponding option descriptor */
 545         descr = find_descr(descrs, '\0', long_opt_name);
 546         if (!descr) {
 547                 try_append_string_printf(error, "Unknown option `--%s`",
 548                         long_opt_name);
 549                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT;
 550                 goto error;
 551         }
 552
 553         /* Find option's argument if any */
 554         if (descr->with_arg) {
 555                 if (eq_pos) {
 556                         /* `--long-opt=arg` style */
 557                         opt_arg = eq_pos + 1;
 558                 } else {
 559                         /* `--long-opt arg` style */
 560                         if (!next_orig_arg) {
 561                                 try_append_string_printf(error,
 562                                         "Missing required argument for option `--%s`",
 563                                         long_opt_name);
 564                                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_MISSING_OPT_ARG;
 565                                 goto error;
 566                         }
 567
 568                         opt_arg = next_orig_arg;
 569                         used_next_orig_arg = true;
 570                 }
 571         } else if (eq_pos) {
 572                 /*
 573                  * Unexpected `--opt=arg` style for a long option which
 574                  * doesn't accept an argument.
 575                  */
 576                 try_append_string_printf(error,
 577                         "Unexpected argument for option `--%s`", long_opt_name);
 578                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_UNEXPECTED_OPT_ARG;
 579                 goto error;
 580         }
 581
 582         /* Create and append option argument */
 583         opt_item = create_opt_item(descr, opt_arg);
 584         if (!opt_item) {
 585                 goto error;
 586         }
 587
 588         if (used_next_orig_arg) {
 589                 iter->i += 2;
 590         } else {
 591                 iter->i++;
 592         }
 593
 594         *item = &opt_item->base;
 595         goto end;
 596
 597 error:
 598         ARGPAR_ASSERT(ret != PARSE_ORIG_ARG_OPT_RET_OK);
 599
 600 end:
 601         return ret;
 602 }
 603
 604 static
 605 enum parse_orig_arg_opt_ret parse_orig_arg_opt(const char * const orig_arg,
 606                 const char * const next_orig_arg,
 607                 const struct argpar_opt_descr * const descrs,
 608                 struct argpar_iter * const iter, char ** const error,
 609                 struct argpar_item ** const item)
 610 {
 611         enum parse_orig_arg_opt_ret ret = PARSE_ORIG_ARG_OPT_RET_OK;
 612
 613         ARGPAR_ASSERT(orig_arg[0] == '-');
 614
 615         if (orig_arg[1] == '-') {
 616                 /* Long option */
 617                 ret = parse_long_opt(&orig_arg[2],
 618                         next_orig_arg, descrs, iter, error, item);
 619         } else {
 620                 /* Short option */
 621                 ret = parse_short_opts(&orig_arg[1],
 622                         next_orig_arg, descrs, iter, error, item);
 623         }
 624
 625         return ret;
 626 }
 627
 628 static
 629 bool try_prepend_while_parsing_arg_to_error(char ** const error,
 630                 const unsigned int i, const char * const arg)
 631 {
 632         char *new_error;
 633         bool success;
 634
 635         if (!error) {
 636                 success = true;
 637                 goto end;
 638         }
 639
 640         ARGPAR_ASSERT(*error);
 641         new_error = argpar_asprintf("While parsing argument #%u (`%s`): %s",
 642                 i + 1, arg, *error);
 643         if (!new_error) {
 644                 success = false;
 645                 goto end;
 646         }
 647
 648         free(*error);
 649         *error = new_error;
 650         success = true;
 651
 652 end:
 653         return success;
 654 }
 655
 656 ARGPAR_HIDDEN
 657 struct argpar_iter *argpar_iter_create(const unsigned int argc,
 658                 const char * const * const argv,
 659                 const struct argpar_opt_descr * const descrs)
 660 {
 661         struct argpar_iter * const iter = ARGPAR_ZALLOC(struct argpar_iter);
 662
 663         if (!iter) {
 664                 goto end;
 665         }
 666
 667         iter->argc = argc;
 668         iter->argv = argv;
 669         iter->descrs = descrs;
 670
 671 end:
 672         return iter;
 673 }
 674
 675 ARGPAR_HIDDEN
 676 void argpar_iter_destroy(struct argpar_iter * const iter)
 677 {
 678         free(iter);
 679 }
 680
 681 ARGPAR_HIDDEN
 682 enum argpar_iter_parse_next_status argpar_iter_parse_next(
 683                 struct argpar_iter * const iter,
 684                 const struct argpar_item ** const item, char ** const error)
 685 {
 686         enum argpar_iter_parse_next_status status;
 687         enum parse_orig_arg_opt_ret parse_orig_arg_opt_ret;
 688         const char *orig_arg;
 689         const char *next_orig_arg;
 690
 691         ARGPAR_ASSERT(iter->i <= iter->argc);
 692
 693         if (error) {
 694                 *error = NULL;
 695         }
 696
 697         if (iter->i == iter->argc) {
 698                 status = ARGPAR_ITER_PARSE_NEXT_STATUS_END;
 699                 goto end;
 700         }
 701
 702         orig_arg = iter->argv[iter->i];
 703         next_orig_arg =
 704                 iter->i < (iter->argc - 1) ? iter->argv[iter->i + 1] : NULL;
 705
 706         if (orig_arg[0] != '-') {
 707                 /* Non-option argument */
 708                 struct argpar_item_non_opt * const non_opt_item =
 709                         create_non_opt_item(orig_arg, iter->i,
 710                                 iter->non_opt_index);
 711
 712                 if (!non_opt_item) {
 713                         status = ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR;
 714                         goto end;
 715                 }
 716
 717                 iter->non_opt_index++;
 718                 iter->i++;
 719                 *item = &non_opt_item->base;
 720                 status = ARGPAR_ITER_PARSE_NEXT_STATUS_OK;
 721                 goto end;
 722         }
 723
 724         /* Option argument */
 725         parse_orig_arg_opt_ret = parse_orig_arg_opt(orig_arg,
 726                 next_orig_arg, iter->descrs, iter, error,
 727                 (struct argpar_item **) item);
 728         switch (parse_orig_arg_opt_ret) {
 729         case PARSE_ORIG_ARG_OPT_RET_OK:
 730                 status = ARGPAR_ITER_PARSE_NEXT_STATUS_OK;
 731                 break;
 732         case PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT:
 733                 try_prepend_while_parsing_arg_to_error(error, iter->i,
 734                         orig_arg);
 735                 status = ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR_UNKNOWN_OPT;
 736                 break;
 737         case PARSE_ORIG_ARG_OPT_RET_ERROR_MISSING_OPT_ARG:
 738         case PARSE_ORIG_ARG_OPT_RET_ERROR_INVALID_OPT:
 739         case PARSE_ORIG_ARG_OPT_RET_ERROR_UNEXPECTED_OPT_ARG:
 740         case PARSE_ORIG_ARG_OPT_RET_ERROR_MEMORY:
 741                 try_prepend_while_parsing_arg_to_error(error, iter->i,
 742                         orig_arg);
 743                 status = ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR;
 744                 break;
 745         default:
 746                 abort();
 747         }
 748
 749 end:
 750         return status;
 751 }
 752
 753 ARGPAR_HIDDEN
 754 unsigned int argpar_iter_get_ingested_orig_args(
 755                 const struct argpar_iter * const iter)
 756 {
 757         return iter->i;
 758 }
 759
 760 ARGPAR_HIDDEN
 761 struct argpar_parse_ret argpar_parse(const unsigned int argc,
 762                 const char * const * const argv,
 763                 const struct argpar_opt_descr * const descrs,
 764                 const bool fail_on_unknown_opt)
 765 {
 766         struct argpar_parse_ret parse_ret = { 0 };
 767         const struct argpar_item *item = NULL;
 768         struct argpar_iter *iter = NULL;
 769
 770         parse_ret.items = create_item_array();
 771         if (!parse_ret.items) {
 772                 parse_ret.error = strdup("Failed to create items array.");
 773                 ARGPAR_ASSERT(parse_ret.error);
 774                 goto error;
 775         }
 776
 777         iter = argpar_iter_create(argc, argv, descrs);
 778         if (!iter) {
 779                 parse_ret.error = strdup("Failed to create argpar iter.");
 780                 ARGPAR_ASSERT(parse_ret.error);
 781                 goto error;
 782         }
 783
 784         while (true) {
 785                 const enum argpar_iter_parse_next_status status =
 786                         argpar_iter_parse_next(iter, &item, &parse_ret.error);
 787
 788                 if (status == ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR) {
 789                         goto error;
 790                 } else if (status == ARGPAR_ITER_PARSE_NEXT_STATUS_END) {
 791                         break;
 792                 } else if (status == ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR_UNKNOWN_OPT) {
 793                         if (fail_on_unknown_opt) {
 794                                 parse_ret.ingested_orig_args =
 795                                         argpar_iter_get_ingested_orig_args(iter);
 796                                 goto error;
 797                         }
 798
 799                         free(parse_ret.error);
 800                         parse_ret.error = NULL;
 801                         break;
 802                 }
 803
 804                 ARGPAR_ASSERT(status == ARGPAR_ITER_PARSE_NEXT_STATUS_OK);
 805
 806                 if (!push_item(parse_ret.items, item)) {
 807                         goto error;
 808                 }
 809
 810                 item = NULL;
 811         }
 812
 813         ARGPAR_ASSERT(!parse_ret.error);
 814         parse_ret.ingested_orig_args = argpar_iter_get_ingested_orig_args(iter);
 815         goto end;
 816
 817 error:
 818         ARGPAR_ASSERT(parse_ret.error);
 819
 820         /* That's how we indicate that an error occurred */
 821         destroy_item_array(parse_ret.items);
 822         parse_ret.items = NULL;
 823
 824 end:
 825         argpar_iter_destroy(iter);
 826         argpar_item_destroy(item);
 827         return parse_ret;
 828 }
 829
 830 ARGPAR_HIDDEN
 831 void argpar_parse_ret_fini(struct argpar_parse_ret * const ret)
 832 {
 833         ARGPAR_ASSERT(ret);
 834         destroy_item_array(ret->items);
 835         ret->items = NULL;
 836         free(ret->error);
 837         ret->error = NULL;
 838 }