argpar/argpar.c

   1 /*
   2  * Copyright 2019 Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 #include <assert.h>
  24 #include <stdarg.h>
  25 #include <stdbool.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include "argpar.h"
  31
  32 #define argpar_realloc(_ptr, _type, _nmemb) ((_type *) realloc(_ptr, (_nmemb) * sizeof(_type)))
  33 #define argpar_calloc(_type, _nmemb) ((_type *) calloc((_nmemb), sizeof(_type)))
  34 #define argpar_zalloc(_type) argpar_calloc(_type, 1)
  35
  36 #define ARGPAR_ASSERT(_cond) assert(_cond)
  37
  38 static
  39 char *argpar_vasprintf(const char *fmt, va_list args)
  40 {
  41         int len1, len2;
  42         char *str;
  43         va_list args2;
  44
  45         va_copy(args2, args);
  46
  47         len1 = vsnprintf(NULL, 0, fmt, args);
  48         if (len1 < 0) {
  49                 str = NULL;
  50                 goto end;
  51         }
  52
  53         str = malloc(len1 + 1);
  54         if (!str) {
  55                 goto end;
  56         }
  57
  58         len2 = vsnprintf(str, len1 + 1, fmt, args2);
  59
  60         ARGPAR_ASSERT(len1 == len2);
  61
  62 end:
  63         return str;
  64 }
  65
  66
  67 static
  68 char *argpar_asprintf(const char *fmt, ...)
  69 {
  70         va_list args;
  71         char *str;
  72
  73         va_start(args, fmt);
  74         str = argpar_vasprintf(fmt, args);
  75         va_end(args);
  76
  77         return str;
  78 }
  79
  80 static
  81 bool argpar_string_append_printf(char **str, const char *fmt, ...)
  82 {
  83         char *new_str = NULL;
  84         char *addendum;
  85         bool success;
  86         va_list args;
  87
  88         ARGPAR_ASSERT(str);
  89
  90         va_start(args, fmt);
  91         addendum = argpar_vasprintf(fmt, args);
  92         va_end(args);
  93
  94         if (!addendum) {
  95                 success = false;
  96                 goto end;
  97         }
  98
  99         new_str = argpar_asprintf("%s%s", *str ? *str : "", addendum);
 100         if (!new_str) {
 101                 success = false;
 102                 goto end;
 103         }
 104
 105         free(*str);
 106         *str = new_str;
 107
 108         success = true;
 109
 110 end:
 111         free(addendum);
 112
 113         return success;
 114 }
 115
 116 static
 117 void destroy_item(struct argpar_item * const item)
 118 {
 119         if (!item) {
 120                 goto end;
 121         }
 122
 123         if (item->type == ARGPAR_ITEM_TYPE_OPT) {
 124                 struct argpar_item_opt * const opt_item = (void *) item;
 125
 126                 free((void *) opt_item->arg);
 127         }
 128
 129         free(item);
 130
 131 end:
 132         return;
 133 }
 134
 135 static
 136 bool push_item(struct argpar_item_array * const array,
 137                 struct argpar_item * const item)
 138 {
 139         bool success;
 140
 141         ARGPAR_ASSERT(array);
 142         ARGPAR_ASSERT(item);
 143
 144         if (array->n_items == array->n_alloc) {
 145                 unsigned int new_n_alloc = array->n_alloc * 2;
 146                 struct argpar_item **new_items;
 147
 148                 new_items = argpar_realloc(array->items,
 149                         struct argpar_item *, new_n_alloc);
 150                 if (!new_items) {
 151                         success = false;
 152                         goto end;
 153                 }
 154
 155                 array->n_alloc = new_n_alloc;
 156                 array->items = new_items;
 157         }
 158
 159         array->items[array->n_items] = item;
 160         array->n_items++;
 161
 162         success = true;
 163
 164 end:
 165         return success;
 166 }
 167
 168 static
 169 void destroy_item_array(struct argpar_item_array * const array)
 170 {
 171         if (array) {
 172                 unsigned int i;
 173
 174                 for (i = 0; i < array->n_items; i++) {
 175                         destroy_item(array->items[i]);
 176                 }
 177
 178                 free(array->items);
 179                 free(array);
 180         }
 181 }
 182
 183 static
 184 struct argpar_item_array *new_item_array(void)
 185 {
 186         struct argpar_item_array *ret;
 187         const int initial_size = 10;
 188
 189         ret = argpar_zalloc(struct argpar_item_array);
 190         if (!ret) {
 191                 goto end;
 192         }
 193
 194         ret->items = argpar_calloc(struct argpar_item *, initial_size);
 195         if (!ret->items) {
 196                 goto error;
 197         }
 198
 199         ret->n_alloc = initial_size;
 200
 201         goto end;
 202
 203 error:
 204         destroy_item_array(ret);
 205         ret = NULL;
 206
 207 end:
 208         return ret;
 209 }
 210
 211 static
 212 struct argpar_item_opt *create_opt_item(
 213                 const struct argpar_opt_descr * const descr,
 214                 const char * const arg)
 215 {
 216         struct argpar_item_opt *opt_item =
 217                 argpar_zalloc(struct argpar_item_opt);
 218
 219         if (!opt_item) {
 220                 goto end;
 221         }
 222
 223         opt_item->base.type = ARGPAR_ITEM_TYPE_OPT;
 224         opt_item->descr = descr;
 225
 226         if (arg) {
 227                 opt_item->arg = strdup(arg);
 228                 if (!opt_item->arg) {
 229                         goto error;
 230                 }
 231         }
 232
 233         goto end;
 234
 235 error:
 236         destroy_item(&opt_item->base);
 237         opt_item = NULL;
 238
 239 end:
 240         return opt_item;
 241 }
 242
 243 static
 244 struct argpar_item_non_opt *create_non_opt_item(const char * const arg,
 245                 const unsigned int orig_index,
 246                 const unsigned int non_opt_index)
 247 {
 248         struct argpar_item_non_opt * const non_opt_item =
 249                 argpar_zalloc(struct argpar_item_non_opt);
 250
 251         if (!non_opt_item) {
 252                 goto end;
 253         }
 254
 255         non_opt_item->base.type = ARGPAR_ITEM_TYPE_NON_OPT;
 256         non_opt_item->arg = arg;
 257         non_opt_item->orig_index = orig_index;
 258         non_opt_item->non_opt_index = non_opt_index;
 259
 260 end:
 261         return non_opt_item;
 262 }
 263
 264 static
 265 const struct argpar_opt_descr *find_descr(
 266                 const struct argpar_opt_descr * const descrs,
 267                 const char short_name, const char * const long_name)
 268 {
 269         const struct argpar_opt_descr *descr;
 270
 271         for (descr = descrs; descr->short_name || descr->long_name; descr++) {
 272                 if (short_name && descr->short_name &&
 273                                 short_name == descr->short_name) {
 274                         goto end;
 275                 }
 276
 277                 if (long_name && descr->long_name &&
 278                                 strcmp(long_name, descr->long_name) == 0) {
 279                         goto end;
 280                 }
 281         }
 282
 283 end:
 284         return !descr->short_name && !descr->long_name ? NULL : descr;
 285 }
 286
 287 enum parse_orig_arg_opt_ret {
 288         PARSE_ORIG_ARG_OPT_RET_OK,
 289         PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT = -2,
 290         PARSE_ORIG_ARG_OPT_RET_ERROR = -1,
 291 };
 292
 293 static
 294 enum parse_orig_arg_opt_ret parse_short_opts(const char * const short_opts,
 295                 const char * const next_orig_arg,
 296                 const struct argpar_opt_descr * const descrs,
 297                 struct argpar_parse_ret * const parse_ret,
 298                 bool * const used_next_orig_arg)
 299 {
 300         enum parse_orig_arg_opt_ret ret = PARSE_ORIG_ARG_OPT_RET_OK;
 301         const char *short_opt_ch = short_opts;
 302
 303         if (strlen(short_opts) == 0) {
 304                 argpar_string_append_printf(&parse_ret->error, "Invalid argument");
 305                 goto error;
 306         }
 307
 308         while (*short_opt_ch) {
 309                 const char *opt_arg = NULL;
 310                 const struct argpar_opt_descr *descr;
 311                 struct argpar_item_opt *opt_item;
 312
 313                 /* Find corresponding option descriptor */
 314                 descr = find_descr(descrs, *short_opt_ch, NULL);
 315                 if (!descr) {
 316                         ret = PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT;
 317                         argpar_string_append_printf(&parse_ret->error,
 318                                 "Unknown option `-%c`", *short_opt_ch);
 319                         goto error;
 320                 }
 321
 322                 if (descr->with_arg) {
 323                         if (short_opt_ch[1]) {
 324                                 /* `-oarg` form */
 325                                 opt_arg = &short_opt_ch[1];
 326                         } else {
 327                                 /* `-o arg` form */
 328                                 opt_arg = next_orig_arg;
 329                                 *used_next_orig_arg = true;
 330                         }
 331
 332                         /*
 333                          * We accept `-o ''` (empty option's argument),
 334                          * but not `-o` alone if an option's argument is
 335                          * expected.
 336                          */
 337                         if (!opt_arg || (short_opt_ch[1] && strlen(opt_arg) == 0)) {
 338                                 argpar_string_append_printf(&parse_ret->error,
 339                                         "Missing required argument for option `-%c`",
 340                                         *short_opt_ch);
 341                                 *used_next_orig_arg = false;
 342                                 goto error;
 343                         }
 344                 }
 345
 346                 /* Create and append option argument */
 347                 opt_item = create_opt_item(descr, opt_arg);
 348                 if (!opt_item) {
 349                         goto error;
 350                 }
 351
 352                 if (!push_item(parse_ret->items, &opt_item->base)) {
 353                         goto error;
 354                 }
 355
 356                 if (descr->with_arg) {
 357                         /* Option has an argument: no more options */
 358                         break;
 359                 }
 360
 361                 /* Go to next short option */
 362                 short_opt_ch++;
 363         }
 364
 365         goto end;
 366
 367 error:
 368         if (ret == PARSE_ORIG_ARG_OPT_RET_OK) {
 369                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR;
 370         }
 371
 372 end:
 373         return ret;
 374 }
 375
 376 static
 377 enum parse_orig_arg_opt_ret parse_long_opt(const char * const long_opt_arg,
 378                 const char * const next_orig_arg,
 379                 const struct argpar_opt_descr * const descrs,
 380                 struct argpar_parse_ret * const parse_ret,
 381                 bool * const used_next_orig_arg)
 382 {
 383         const size_t max_len = 127;
 384         enum parse_orig_arg_opt_ret ret = PARSE_ORIG_ARG_OPT_RET_OK;
 385         const struct argpar_opt_descr *descr;
 386         struct argpar_item_opt *opt_item;
 387
 388         /* Option's argument, if any */
 389         const char *opt_arg = NULL;
 390
 391         /* Position of first `=`, if any */
 392         const char *eq_pos;
 393
 394         /* Buffer holding option name when `long_opt_arg` contains `=` */
 395         char buf[max_len + 1];
 396
 397         /* Option name */
 398         const char *long_opt_name = long_opt_arg;
 399
 400         if (strlen(long_opt_arg) == 0) {
 401                 argpar_string_append_printf(&parse_ret->error,
 402                         "Invalid argument");
 403                 goto error;
 404         }
 405
 406         /* Find the first `=` in original argument */
 407         eq_pos = strchr(long_opt_arg, '=');
 408         if (eq_pos) {
 409                 const size_t long_opt_name_size = eq_pos - long_opt_arg;
 410
 411                 /* Isolate the option name */
 412                 if (long_opt_name_size > max_len) {
 413                         argpar_string_append_printf(&parse_ret->error,
 414                                 "Invalid argument `--%s`", long_opt_arg);
 415                         goto error;
 416                 }
 417
 418                 memcpy(buf, long_opt_arg, long_opt_name_size);
 419                 buf[long_opt_name_size] = '\0';
 420                 long_opt_name = buf;
 421         }
 422
 423         /* Find corresponding option descriptor */
 424         descr = find_descr(descrs, '\0', long_opt_name);
 425         if (!descr) {
 426                 argpar_string_append_printf(&parse_ret->error,
 427                         "Unknown option `--%s`", long_opt_name);
 428                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT;
 429                 goto error;
 430         }
 431
 432         /* Find option's argument if any */
 433         if (descr->with_arg) {
 434                 if (eq_pos) {
 435                         /* `--long-opt=arg` style */
 436                         opt_arg = eq_pos + 1;
 437                 } else {
 438                         /* `--long-opt arg` style */
 439                         if (!next_orig_arg) {
 440                                 argpar_string_append_printf(&parse_ret->error,
 441                                         "Missing required argument for option `--%s`",
 442                                         long_opt_name);
 443                                 goto error;
 444                         }
 445
 446                         opt_arg = next_orig_arg;
 447                         *used_next_orig_arg = true;
 448                 }
 449         }
 450
 451         /* Create and append option argument */
 452         opt_item = create_opt_item(descr, opt_arg);
 453         if (!opt_item) {
 454                 goto error;
 455         }
 456
 457         if (!push_item(parse_ret->items, &opt_item->base)) {
 458                 goto error;
 459         }
 460
 461         goto end;
 462
 463 error:
 464         if (ret == PARSE_ORIG_ARG_OPT_RET_OK) {
 465                 ret = PARSE_ORIG_ARG_OPT_RET_ERROR;
 466         }
 467
 468 end:
 469         return ret;
 470 }
 471
 472 static
 473 enum parse_orig_arg_opt_ret parse_orig_arg_opt(const char * const orig_arg,
 474                 const char * const next_orig_arg,
 475                 const struct argpar_opt_descr * const descrs,
 476                 struct argpar_parse_ret * const parse_ret,
 477                 bool * const used_next_orig_arg)
 478 {
 479         enum parse_orig_arg_opt_ret ret = PARSE_ORIG_ARG_OPT_RET_OK;
 480
 481         ARGPAR_ASSERT(orig_arg[0] == '-');
 482
 483         if (orig_arg[1] == '-') {
 484                 /* Long option */
 485                 ret = parse_long_opt(&orig_arg[2],
 486                         next_orig_arg, descrs, parse_ret,
 487                         used_next_orig_arg);
 488         } else {
 489                 /* Short option */
 490                 ret = parse_short_opts(&orig_arg[1],
 491                         next_orig_arg, descrs, parse_ret,
 492                         used_next_orig_arg);
 493         }
 494
 495         return ret;
 496 }
 497
 498 static
 499 bool prepend_while_parsing_arg_to_error(char **error,
 500                 const unsigned int i, const char * const arg)
 501 {
 502         char *new_error;
 503         bool success;
 504
 505         ARGPAR_ASSERT(error);
 506         ARGPAR_ASSERT(*error);
 507
 508         new_error = argpar_asprintf("While parsing argument #%u (`%s`): %s",
 509                 i + 1, arg, *error);
 510         if (!new_error) {
 511                 success = false;
 512                 goto end;
 513         }
 514
 515         free(*error);
 516         *error = new_error;
 517         success = true;
 518
 519 end:
 520         return success;
 521 }
 522
 523 ARGPAR_HIDDEN
 524 struct argpar_parse_ret argpar_parse(unsigned int argc,
 525                 const char * const *argv,
 526                 const struct argpar_opt_descr * const descrs,
 527                 bool fail_on_unknown_opt)
 528 {
 529         struct argpar_parse_ret parse_ret = { 0 };
 530         unsigned int i;
 531         unsigned int non_opt_index = 0;
 532
 533         parse_ret.items = new_item_array();
 534         if (!parse_ret.items) {
 535                 goto error;
 536         }
 537
 538         for (i = 0; i < argc; i++) {
 539                 enum parse_orig_arg_opt_ret parse_orig_arg_opt_ret;
 540                 bool used_next_orig_arg = false;
 541                 const char * const orig_arg = argv[i];
 542                 const char * const next_orig_arg =
 543                         i < argc - 1 ? argv[i + 1] : NULL;
 544
 545                 if (orig_arg[0] != '-') {
 546                         /* Non-option argument */
 547                         struct argpar_item_non_opt *non_opt_item =
 548                                 create_non_opt_item(orig_arg, i, non_opt_index);
 549
 550                         if (!non_opt_item) {
 551                                 goto error;
 552                         }
 553
 554                         non_opt_index++;
 555
 556                         if (!push_item(parse_ret.items, &non_opt_item->base)) {
 557                                 goto error;
 558                         }
 559
 560                         continue;
 561                 }
 562
 563                 /* Option argument */
 564                 parse_orig_arg_opt_ret = parse_orig_arg_opt(orig_arg,
 565                         next_orig_arg, descrs, &parse_ret, &used_next_orig_arg);
 566                 switch (parse_orig_arg_opt_ret) {
 567                 case PARSE_ORIG_ARG_OPT_RET_OK:
 568                         break;
 569                 case PARSE_ORIG_ARG_OPT_RET_ERROR_UNKNOWN_OPT:
 570                         ARGPAR_ASSERT(!used_next_orig_arg);
 571
 572                         if (fail_on_unknown_opt) {
 573                                 prepend_while_parsing_arg_to_error(
 574                                         &parse_ret.error, i, orig_arg);
 575                                 goto error;
 576                         }
 577
 578                         /*
 579                          * The current original argument is not
 580                          * considered ingested because it triggered an
 581                          * unknown option.
 582                          */
 583                         parse_ret.ingested_orig_args = i;
 584                         free(parse_ret.error);
 585                         parse_ret.error = NULL;
 586                         goto end;
 587                 case PARSE_ORIG_ARG_OPT_RET_ERROR:
 588                         prepend_while_parsing_arg_to_error(
 589                                 &parse_ret.error, i, orig_arg);
 590                         goto error;
 591                 default:
 592                         abort();
 593                 }
 594
 595                 if (used_next_orig_arg) {
 596                         i++;
 597                 }
 598         }
 599
 600         parse_ret.ingested_orig_args = argc;
 601         free(parse_ret.error);
 602         parse_ret.error = NULL;
 603         goto end;
 604
 605 error:
 606         /* That's how we indicate that an error occured */
 607         destroy_item_array(parse_ret.items);
 608         parse_ret.items = NULL;
 609
 610 end:
 611         return parse_ret;
 612 }
 613
 614 ARGPAR_HIDDEN
 615 void argpar_parse_ret_fini(struct argpar_parse_ret *ret)
 616 {
 617         ARGPAR_ASSERT(ret);
 618
 619         destroy_item_array(ret->items);
 620         ret->items = NULL;
 621
 622         free(ret->error);
 623         ret->error = NULL;
 624 }