1/* $NetBSD: refuse_opt.c,v 1.23 2022/01/22 07:58:32 pho Exp $ */ 2 3/*- 4 * Copyright (c) 2007 Juan Romero Pardines. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28#include <sys/types.h> 29 30#include <err.h> 31#include <fuse_internal.h> 32#include <fuse_opt.h> 33#include <stdbool.h> 34#include <stdio.h> 35#include <stdlib.h> 36#include <string.h> 37 38#ifdef FUSE_OPT_DEBUG 39#define DPRINTF(x) do { printf x; } while ( /* CONSTCOND */ 0) 40#else 41#define DPRINTF(x) 42#endif 43 44/* 45 * Public API. 46 */ 47 48/* ARGSUSED */ 49int 50fuse_opt_add_arg(struct fuse_args *args, const char *arg) 51{ 52 struct fuse_args *ap; 53 54 if (args->allocated == 0) { 55 ap = fuse_opt_deep_copy_args(args->argc, args->argv); 56 args->argv = ap->argv; 57 args->argc = ap->argc; 58 args->allocated = ap->allocated; 59 (void) free(ap); 60 } else if (args->allocated == args->argc) { 61 int na = args->allocated + 10; 62 63 if (reallocarr(&args->argv, (size_t)na, sizeof(*args->argv)) != 0) 64 return -1; 65 66 args->allocated = na; 67 } 68 DPRINTF(("%s: arguments passed: [arg:%s]\n", __func__, arg)); 69 if ((args->argv[args->argc++] = strdup(arg)) == NULL) 70 err(1, "fuse_opt_add_arg"); 71 args->argv[args->argc] = NULL; 72 return 0; 73} 74 75struct fuse_args * 76fuse_opt_deep_copy_args(int argc, char **argv) 77{ 78 struct fuse_args *ap; 79 int i; 80 81 if ((ap = malloc(sizeof(*ap))) == NULL) 82 err(1, "_fuse_deep_copy_args"); 83 /* deep copy args structure into channel args */ 84 ap->allocated = ((argc / 10) + 1) * 10; 85 86 if ((ap->argv = calloc((size_t)ap->allocated, 87 sizeof(*ap->argv))) == NULL) 88 err(1, "_fuse_deep_copy_args"); 89 90 for (i = 0; i < argc; i++) { 91 if ((ap->argv[i] = strdup(argv[i])) == NULL) 92 err(1, "_fuse_deep_copy_args"); 93 } 94 ap->argv[ap->argc = i] = NULL; 95 return ap; 96} 97 98void 99fuse_opt_free_args(struct fuse_args *ap) 100{ 101 if (ap) { 102 if (ap->allocated) { 103 int i; 104 for (i = 0; i < ap->argc; i++) { 105 free(ap->argv[i]); 106 } 107 free(ap->argv); 108 } 109 ap->argv = NULL; 110 ap->allocated = ap->argc = 0; 111 } 112} 113 114/* ARGSUSED */ 115int 116fuse_opt_insert_arg(struct fuse_args *args, int pos, const char *arg) 117{ 118 int i; 119 int na; 120 121 DPRINTF(("%s: arguments passed: [pos=%d] [arg=%s]\n", 122 __func__, pos, arg)); 123 if (args->argv == NULL) { 124 na = 10; 125 } else { 126 na = args->allocated + 10; 127 } 128 if (reallocarr(&args->argv, (size_t)na, sizeof(*args->argv)) != 0) { 129 warn("fuse_opt_insert_arg"); 130 return -1; 131 } 132 args->allocated = na; 133 134 for (i = args->argc++; i > pos; --i) { 135 args->argv[i] = args->argv[i - 1]; 136 } 137 if ((args->argv[pos] = strdup(arg)) == NULL) 138 err(1, "fuse_opt_insert_arg"); 139 args->argv[args->argc] = NULL; 140 return 0; 141} 142 143static int add_opt(char **opts, const char *opt, bool escape) 144{ 145 const size_t orig_len = *opts == NULL ? 0 : strlen(*opts); 146 char* buf = realloc(*opts, orig_len + 1 + strlen(opt) * 2 + 1); 147 148 if (buf == NULL) { 149 return -1; 150 } 151 *opts = buf; 152 153 if (orig_len > 0) { 154 buf += orig_len; 155 *buf++ = ','; 156 } 157 158 for (; *opt; opt++) { 159 if (escape && (*opt == ',' || *opt == '\\')) { 160 *buf++ = '\\'; 161 } 162 *buf++ = *opt; 163 } 164 *buf = '\0'; 165 166 return 0; 167} 168 169int fuse_opt_add_opt(char **opts, const char *opt) 170{ 171 DPRINTF(("%s: arguments passed: [opts=%s] [opt=%s]\n", 172 __func__, *opts, opt)); 173 return add_opt(opts, opt, false); 174} 175 176int fuse_opt_add_opt_escaped(char **opts, const char *opt) 177{ 178 DPRINTF(("%s: arguments passed: [opts=%s] [opt=%s]\n", 179 __func__, *opts, opt)); 180 return add_opt(opts, opt, true); 181} 182 183static bool match_templ(const char *templ, const char *opt, ssize_t *sep_idx) 184{ 185 const char *sep = strpbrk(templ, "= "); 186 187 if (sep != NULL && (sep[1] == '\0' || sep[1] == '%')) { 188 const size_t cmp_len = 189 (size_t)(sep[0] == '=' ? sep - templ + 1 : sep - templ); 190 191 if (strlen(opt) >= cmp_len && strncmp(templ, opt, cmp_len) == 0) { 192 if (sep_idx != NULL) 193 *sep_idx = (ssize_t)(sep - templ); 194 return true; 195 } 196 else { 197 return false; 198 } 199 } 200 else { 201 if (strcmp(templ, opt) == 0) { 202 if (sep_idx != NULL) 203 *sep_idx = -1; 204 return true; 205 } 206 else { 207 return false; 208 } 209 } 210} 211 212static const struct fuse_opt * 213find_opt(const struct fuse_opt *opts, const char *opt, ssize_t *sep_idx) 214{ 215 for (; opts != NULL && opts->templ != NULL; opts++) { 216 if (match_templ(opts->templ, opt, sep_idx)) 217 return opts; 218 } 219 return NULL; 220} 221 222/* 223 * Returns 1 if opt was matched with any option from opts, 224 * otherwise returns 0. 225 */ 226int 227fuse_opt_match(const struct fuse_opt *opts, const char *opt) 228{ 229 return find_opt(opts, opt, NULL) != NULL ? 1 : 0; 230} 231 232static int call_proc(fuse_opt_proc_t proc, void* data, 233 const char* arg, int key, struct fuse_args *outargs, bool is_opt) 234{ 235 if (key == FUSE_OPT_KEY_DISCARD) 236 return 0; 237 238 if (key != FUSE_OPT_KEY_KEEP && proc != NULL) { 239 const int rv = proc(data, arg, key, outargs); 240 241 if (rv == -1 || /* error */ 242 rv == 0 /* discard */) 243 return rv; 244 } 245 246 if (is_opt) { 247 /* Do we already have "-o" at the beginning of outargs? */ 248 if (outargs->argc >= 3 && strcmp(outargs->argv[1], "-o") == 0) { 249 /* Append the option to the comma-separated list. */ 250 if (fuse_opt_add_opt_escaped(&outargs->argv[2], arg) == -1) 251 return -1; 252 } 253 else { 254 /* Insert -o arg at the beginning. */ 255 if (fuse_opt_insert_arg(outargs, 1, "-o") == -1) 256 return -1; 257 if (fuse_opt_insert_arg(outargs, 2, arg) == -1) 258 return -1; 259 } 260 } 261 else { 262 if (fuse_opt_add_arg(outargs, arg) == -1) 263 return -1; 264 } 265 266 return 0; 267} 268 269/* Skip the current argv if possible. */ 270static int next_arg(const struct fuse_args *args, int *i) 271{ 272 if (*i + 1 >= args->argc) { 273 (void)fprintf(stderr, "fuse: missing argument" 274 " after '%s'\n", args->argv[*i]); 275 return -1; 276 } 277 else { 278 *i += 1; 279 return 0; 280 } 281} 282 283/* Parse a single argument with a matched template. */ 284static int 285parse_matched_arg(const char* arg, struct fuse_args *outargs, 286 const struct fuse_opt* opt, ssize_t sep_idx, void* data, 287 fuse_opt_proc_t proc, bool is_opt) 288{ 289 if (opt->offset == -1) { 290 /* The option description does not want any variables to be 291 * updated.*/ 292 if (call_proc(proc, data, arg, opt->value, outargs, is_opt) == -1) 293 return -1; 294 } 295 else { 296 void *var = (char*)data + opt->offset; 297 298 if (sep_idx > 0 && opt->templ[sep_idx + 1] == '%') { 299 /* "foo=%y" or "-x %y" */ 300 const char* param = 301 opt->templ[sep_idx] == '=' ? &arg[sep_idx + 1] : &arg[sep_idx]; 302 303 if (opt->templ[sep_idx + 2] == 's') { 304 char* dup = strdup(param); 305 if (dup == NULL) 306 return -1; 307 308 *(char **)var = dup; 309 } 310 else { 311 /* The format string is not a literal. We all know 312 * this is a bad idea but it's exactly what fuse_opt 313 * wants to do... */ 314#pragma GCC diagnostic push 315#pragma GCC diagnostic ignored "-Wformat-nonliteral" 316 if (sscanf(param, &opt->templ[sep_idx + 1], var) == -1) { 317#pragma GCC diagnostic pop 318 (void)fprintf(stderr, "fuse: '%s' is not a " 319 "valid parameter for option '%.*s'\n", 320 param, (int)sep_idx, opt->templ); 321 return -1; 322 } 323 } 324 } 325 else { 326 /* No parameter format is given. */ 327 *(int *)var = opt->value; 328 } 329 } 330 return 0; 331} 332 333/* Parse a single argument with matching templates. */ 334static int 335parse_arg(struct fuse_args* args, int *argi, const char* arg, 336 struct fuse_args *outargs, void *data, 337 const struct fuse_opt *opts, fuse_opt_proc_t proc, bool is_opt) 338{ 339 ssize_t sep_idx; 340 const struct fuse_opt *opt = find_opt(opts, arg, &sep_idx); 341 342 if (opt) { 343 /* An argument can match to multiple templates. Process them 344 * all. */ 345 for (; opt != NULL && opt->templ != NULL; 346 opt = find_opt(++opt, arg, &sep_idx)) { 347 348 if (sep_idx > 0 && opt->templ[sep_idx] == ' ' && 349 arg[sep_idx] == '\0') { 350 /* The template "-x %y" requests a separate 351 * parameter "%y". Try to find one. */ 352 char *new_arg; 353 int rv; 354 355 if (next_arg(args, argi) == -1) 356 return -1; 357 358 /* ...but processor callbacks expect a concatenated 359 * argument "-xfoo". */ 360 if ((new_arg = malloc((size_t)sep_idx + 361 strlen(args->argv[*argi]) + 1)) == NULL) 362 return -1; 363 364 strncpy(new_arg, arg, (size_t)sep_idx); /* -x */ 365 strcpy(new_arg + sep_idx, args->argv[*argi]); /* foo */ 366 rv = parse_matched_arg(new_arg, outargs, opt, sep_idx, 367 data, proc, is_opt); 368 free(new_arg); 369 370 if (rv == -1) 371 return -1; 372 } 373 else { 374 int rv; 375 rv = parse_matched_arg(arg, outargs, opt, sep_idx, 376 data, proc, is_opt); 377 if (rv == -1) 378 return -1; 379 } 380 } 381 return 0; 382 } 383 else { 384 /* No templates matched to it so just invoke the callback. */ 385 return call_proc(proc, data, arg, FUSE_OPT_KEY_OPT, outargs, is_opt); 386 } 387} 388 389/* Parse a comma-separated list of options which possibly has escaped 390 * characters. */ 391static int 392parse_opts(struct fuse_args *args, int *argi, const char* arg, 393 struct fuse_args *outargs, void *data, 394 const struct fuse_opt *opts, fuse_opt_proc_t proc) 395{ 396 char *opt; 397 size_t i, opt_len = 0; 398 399 /* An unescaped option can never be longer than the original 400 * list. */ 401 if ((opt = malloc(strlen(arg) + 1)) == NULL) 402 return -1; 403 404 for (i = 0; i < strlen(arg); i++) { 405 if (arg[i] == ',') { 406 opt[opt_len] = '\0'; 407 if (parse_arg(args, argi, opt, outargs, 408 data, opts, proc, true) == -1) { 409 free(opt); 410 return -1; 411 } 412 /* Start a new option. */ 413 opt_len = 0; 414 } 415 else if (arg[i] == '\\' && arg[i+1] != '\0') { 416 /* Unescape it. */ 417 opt[opt_len++] = arg[i+1]; 418 i++; 419 } 420 else { 421 opt[opt_len++] = arg[i]; 422 } 423 } 424 425 /* Parse the last option here. */ 426 opt[opt_len] = '\0'; 427 if (parse_arg(args, argi, opt, outargs, data, opts, proc, true) == -1) { 428 free(opt); 429 return -1; 430 } 431 432 free(opt); 433 return 0; 434} 435 436static int 437parse_all(struct fuse_args *args, struct fuse_args *outargs, void *data, 438 const struct fuse_opt *opts, fuse_opt_proc_t proc) 439{ 440 bool nonopt = false; /* Have we seen the "--" marker? */ 441 int i; 442 443 /* The first argument, the program name, is implicitly 444 * FUSE_OPT_KEY_KEEP. */ 445 if (args->argc > 0) { 446 if (fuse_opt_add_arg(outargs, args->argv[0]) == -1) 447 return -1; 448 } 449 450 /* the real loop to process the arguments */ 451 for (i = 1; i < args->argc; i++) { 452 const char *arg = args->argv[i]; 453 454 /* argvn != -foo... */ 455 if (nonopt || arg[0] != '-') { 456 if (call_proc(proc, data, arg, FUSE_OPT_KEY_NONOPT, 457 outargs, false) == -1) 458 return -1; 459 } 460 /* -o or -ofoo */ 461 else if (arg[1] == 'o') { 462 /* -oblah,foo... */ 463 if (arg[2] != '\0') { 464 /* skip -o */ 465 if (parse_opts(args, &i, arg + 2, outargs, 466 data, opts, proc) == -1) 467 return -1; 468 } 469 /* -o blah,foo... */ 470 else { 471 if (next_arg(args, &i) == -1) 472 return -1; 473 if (parse_opts(args, &i, args->argv[i], outargs, 474 data, opts, proc) == -1) 475 return -1; 476 } 477 } 478 /* -- */ 479 else if (arg[1] == '-' && arg[2] == '\0') { 480 if (fuse_opt_add_arg(outargs, arg) == -1) 481 return -1; 482 nonopt = true; 483 } 484 /* -foo */ 485 else { 486 if (parse_arg(args, &i, arg, outargs, 487 data, opts, proc, false) == -1) 488 return -1; 489 } 490 } 491 492 /* The "--" marker at the last of outargs should be removed */ 493 if (nonopt && strcmp(outargs->argv[outargs->argc - 1], "--") == 0) { 494 free(outargs->argv[outargs->argc - 1]); 495 outargs->argv[--outargs->argc] = NULL; 496 } 497 498 return 0; 499} 500 501int 502fuse_opt_parse(struct fuse_args *args, void *data, 503 const struct fuse_opt *opts, fuse_opt_proc_t proc) 504{ 505 struct fuse_args outargs = FUSE_ARGS_INIT(0, NULL); 506 int rv; 507 508 if (!args || !args->argv || !args->argc) 509 return 0; 510 511 rv = parse_all(args, &outargs, data, opts, proc); 512 if (rv != -1) { 513 /* Succeeded. Swap the outargs and args. */ 514 struct fuse_args tmp = *args; 515 *args = outargs; 516 outargs = tmp; 517 } 518 519 fuse_opt_free_args(&outargs); 520 return rv; 521} 522