file.c

   1 /*
   2  * libuci - Library for the Unified Configuration Interface
   3  * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU Lesser General Public License for more details.
  13  */
  14
  15 /*
  16  * This file contains the code for parsing uci config files
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22 #include <sys/file.h>
  23 #include <stdbool.h>
  24 #include <unistd.h>
  25 #include <fcntl.h>
  26 #include <stdio.h>
  27 #include <ctype.h>
  28 #include <glob.h>
  29 #include <string.h>
  30 #include <stdlib.h>
  31
  32 #include "uci.h"
  33 #include "uci_internal.h"
  34
  35 #define LINEBUF 32
  36 #define LINEBUF_MAX     4096
  37
  38 /*
  39  * Fetch a new line from the input stream and resize buffer if necessary
  40  */
  41 __private void uci_getln(struct uci_context *ctx, int offset)
  42 {
  43         struct uci_parse_context *pctx = ctx->pctx;
  44         char *p;
  45         int ofs;
  46
  47         if (pctx->buf == NULL) {
  48                 pctx->buf = uci_malloc(ctx, LINEBUF);
  49                 pctx->bufsz = LINEBUF;
  50         }
  51         /* It takes 2 slots for fgets to read 1 char. */
  52         if (offset >= pctx->bufsz - 1) {
  53                 pctx->bufsz *= 2;
  54                 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
  55         }
  56
  57         ofs = offset;
  58         do {
  59                 p = &pctx->buf[ofs];
  60                 p[0] = 0;
  61
  62                 p = fgets(p, pctx->bufsz - ofs, pctx->file);
  63                 if (!p || !*p)
  64                         return;
  65
  66                 ofs += strlen(p);
  67                 if (pctx->buf[ofs - 1] == '\n') {
  68                         pctx->line++;
  69                         return;
  70                 }
  71
  72                 if (pctx->bufsz > LINEBUF_MAX/2)
  73                         uci_parse_error(ctx, "line too long");
  74
  75                 pctx->bufsz *= 2;
  76                 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
  77         } while (1);
  78 }
  79
  80 /*
  81  * parse a character escaped by '\'
  82  * returns true if the escaped character is to be parsed
  83  * returns false if the escaped character is to be ignored
  84  */
  85 static bool parse_backslash(struct uci_context *ctx)
  86 {
  87         struct uci_parse_context *pctx = ctx->pctx;
  88
  89         /* skip backslash */
  90         pctx->pos += 1;
  91
  92         /* undecoded backslash at the end of line, fetch the next line */
  93         if (!pctx_cur_char(pctx) ||
  94             pctx_cur_char(pctx) == '\n' ||
  95             (pctx_cur_char(pctx) == '\r' &&
  96              pctx_char(pctx, pctx_pos(pctx) + 1) == '\n' &&
  97              !pctx_char(pctx, pctx_pos(pctx) + 2))) {
  98                 uci_getln(ctx, pctx->pos);
  99                 return false;
 100         }
 101
 102         /* FIXME: decode escaped char, necessary? */
 103         return true;
 104 }
 105
 106 /*
 107  * move the string pointer forward until a non-whitespace character or
 108  * EOL is reached
 109  */
 110 static void skip_whitespace(struct uci_context *ctx)
 111 {
 112         struct uci_parse_context *pctx = ctx->pctx;
 113
 114         while (pctx_cur_char(pctx) && isspace(pctx_cur_char(pctx)))
 115                 pctx->pos += 1;
 116 }
 117
 118 static inline void addc(struct uci_context *ctx, int *pos_dest, int *pos_src)
 119 {
 120         struct uci_parse_context *pctx = ctx->pctx;
 121
 122         pctx_char(pctx, *pos_dest) = pctx_char(pctx, *pos_src);
 123         *pos_dest += 1;
 124         *pos_src += 1;
 125 }
 126
 127 /*
 128  * parse a double quoted string argument from the command line
 129  */
 130 static void parse_double_quote(struct uci_context *ctx, int *target)
 131 {
 132         struct uci_parse_context *pctx = ctx->pctx;
 133         char c;
 134
 135         /* skip quote character */
 136         pctx->pos += 1;
 137
 138         while (1) {
 139                 c = pctx_cur_char(pctx);
 140                 switch(c) {
 141                 case '"':
 142                         pctx->pos += 1;
 143                         return;
 144                 case 0:
 145                         /* Multi-line str value */
 146                         uci_getln(ctx, pctx->pos);
 147                         if (!pctx_cur_char(pctx)) {
 148                                 uci_parse_error(ctx, "EOF with unterminated \"");
 149                         }
 150                         break;
 151                 case '\\':
 152                         if (!parse_backslash(ctx))
 153                                 continue;
 154                         /* fall through */
 155                 default:
 156                         addc(ctx, target, &pctx->pos);
 157                         break;
 158                 }
 159         }
 160 }
 161
 162 /*
 163  * parse a single quoted string argument from the command line
 164  */
 165 static void parse_single_quote(struct uci_context *ctx, int *target)
 166 {
 167         struct uci_parse_context *pctx = ctx->pctx;
 168         char c;
 169         /* skip quote character */
 170         pctx->pos += 1;
 171
 172         while (1) {
 173                 c = pctx_cur_char(pctx);
 174                 switch(c) {
 175                 case '\'':
 176                         pctx->pos += 1;
 177                         return;
 178                 case 0:
 179                         /* Multi-line str value */
 180                         uci_getln(ctx, pctx->pos);
 181                         if (!pctx_cur_char(pctx))
 182                                 uci_parse_error(ctx, "EOF with unterminated '");
 183
 184                         break;
 185                 default:
 186                         addc(ctx, target, &pctx->pos);
 187                 }
 188         }
 189 }
 190
 191 /*
 192  * parse a string from the command line and detect the quoting style
 193  */
 194 static void parse_str(struct uci_context *ctx, int *target)
 195 {
 196         struct uci_parse_context *pctx = ctx->pctx;
 197         bool next = true;
 198         do {
 199                 switch(pctx_cur_char(pctx)) {
 200                 case '\'':
 201                         parse_single_quote(ctx, target);
 202                         break;
 203                 case '"':
 204                         parse_double_quote(ctx, target);
 205                         break;
 206                 case '#':
 207                         pctx_cur_char(pctx) = 0;
 208                         /* fall through */
 209                 case 0:
 210                         goto done;
 211                 case ';':
 212                         next = false;
 213                         goto done;
 214                 case '\\':
 215                         if (!parse_backslash(ctx))
 216                                 continue;
 217                         /* fall through */
 218                 default:
 219                         addc(ctx, target, &pctx->pos);
 220                         break;
 221                 }
 222         } while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
 223 done:
 224
 225         /*
 226          * if the string was unquoted and we've stopped at a whitespace
 227          * character, skip to the next one, because the whitespace will
 228          * be overwritten by a null byte here
 229          */
 230         if (pctx_cur_char(pctx) && next)
 231                 pctx->pos += 1;
 232
 233         /* terminate the parsed string */
 234         pctx_char(pctx, *target) = 0;
 235 }
 236
 237 /*
 238  * extract the next argument from the command line
 239  */
 240 static int next_arg(struct uci_context *ctx, bool required, bool name, bool package)
 241 {
 242         struct uci_parse_context *pctx = ctx->pctx;
 243         int val, ptr;
 244
 245         skip_whitespace(ctx);
 246         val = ptr = pctx_pos(pctx);
 247         if (pctx_cur_char(pctx) == ';') {
 248                 pctx_cur_char(pctx) = 0;
 249                 pctx->pos += 1;
 250         } else {
 251                 parse_str(ctx, &ptr);
 252         }
 253         if (!pctx_char(pctx, val)) {
 254                 if (required)
 255                         uci_parse_error(ctx, "insufficient arguments");
 256                 goto done;
 257         }
 258
 259         if (name && !uci_validate_str(pctx_str(pctx, val), name, package))
 260                 uci_parse_error(ctx, "invalid character in name field");
 261
 262 done:
 263         return val;
 264 }
 265
 266 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
 267 {
 268         int ofs_result;
 269
 270         UCI_HANDLE_ERR(ctx);
 271         UCI_ASSERT(ctx, str != NULL);
 272         UCI_ASSERT(ctx, result != NULL);
 273
 274         if (ctx->pctx && (ctx->pctx->file != stream))
 275                 uci_cleanup(ctx);
 276
 277         if (!ctx->pctx)
 278                 uci_alloc_parse_context(ctx);
 279
 280         ctx->pctx->file = stream;
 281         if (!*str) {
 282                 ctx->pctx->pos = 0;
 283                 uci_getln(ctx, 0);
 284         }
 285
 286         ofs_result = next_arg(ctx, false, false, false);
 287         *result = pctx_str(ctx->pctx, ofs_result);
 288         *str = pctx_cur_str(ctx->pctx);
 289
 290         return 0;
 291 }
 292
 293 static int
 294 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
 295 {
 296         UCI_ASSERT(ctx, ptr != NULL);
 297         UCI_ASSERT(ctx, e != NULL);
 298
 299         memset(ptr, 0, sizeof(struct uci_ptr));
 300         switch(e->type) {
 301         case UCI_TYPE_OPTION:
 302                 ptr->o = uci_to_option(e);
 303                 goto fill_option;
 304         case UCI_TYPE_SECTION:
 305                 ptr->s = uci_to_section(e);
 306                 goto fill_section;
 307         case UCI_TYPE_PACKAGE:
 308                 ptr->p = uci_to_package(e);
 309                 goto fill_package;
 310         default:
 311                 UCI_THROW(ctx, UCI_ERR_INVAL);
 312         }
 313
 314 fill_option:
 315         ptr->option = ptr->o->e.name;
 316         ptr->s = ptr->o->section;
 317 fill_section:
 318         ptr->section = ptr->s->e.name;
 319         ptr->p = ptr->s->package;
 320 fill_package:
 321         ptr->package = ptr->p->e.name;
 322
 323         ptr->flags |= UCI_LOOKUP_DONE;
 324
 325         return 0;
 326 }
 327
 328
 329
 330 /*
 331  * verify that the end of the line or command is reached.
 332  * throw an error if extra arguments are given on the command line
 333  */
 334 static void assert_eol(struct uci_context *ctx)
 335 {
 336         char *tmp;
 337         int ofs_tmp;
 338
 339         skip_whitespace(ctx);
 340         ofs_tmp = next_arg(ctx, false, false, false);
 341         tmp = pctx_str(ctx->pctx, ofs_tmp);
 342         if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
 343                 uci_parse_error(ctx, "too many arguments");
 344 }
 345
 346 /*
 347  * switch to a different config, either triggered by uci_load, or by a
 348  * 'package <...>' statement in the import file
 349  */
 350 static void uci_switch_config(struct uci_context *ctx)
 351 {
 352         struct uci_parse_context *pctx;
 353         struct uci_element *e;
 354         const char *name;
 355
 356         pctx = ctx->pctx;
 357         name = pctx->name;
 358
 359         /* add the last config to main config file list */
 360         if (pctx->package) {
 361                 pctx->package->backend = ctx->backend;
 362                 uci_list_add(&ctx->root, &pctx->package->e.list);
 363
 364                 pctx->package = NULL;
 365                 pctx->section = NULL;
 366         }
 367
 368         if (!name)
 369                 return;
 370
 371         /*
 372          * if an older config under the same name exists, unload it
 373          * ignore errors here, e.g. if the config was not found
 374          */
 375         e = uci_lookup_list(&ctx->root, name);
 376         if (e)
 377                 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 378         pctx->package = uci_alloc_package(ctx, name);
 379 }
 380
 381 /*
 382  * parse the 'package' uci command (next config package)
 383  */
 384 static void uci_parse_package(struct uci_context *ctx, bool single)
 385 {
 386         struct uci_parse_context *pctx = ctx->pctx;
 387         int ofs_name;
 388         char *name;
 389
 390         /* command string null-terminated by strtok */
 391         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 392
 393         ofs_name = next_arg(ctx, true, true, true);
 394         name = pctx_str(pctx, ofs_name);
 395         assert_eol(ctx);
 396         if (single)
 397                 return;
 398
 399         ctx->pctx->name = name;
 400         uci_switch_config(ctx);
 401 }
 402
 403 /*
 404  * parse the 'config' uci command (open a section)
 405  */
 406 static void uci_parse_config(struct uci_context *ctx)
 407 {
 408         struct uci_parse_context *pctx = ctx->pctx;
 409         struct uci_element *e;
 410         struct uci_ptr ptr;
 411         int ofs_name, ofs_type;
 412         char *name;
 413         char *type;
 414
 415         uci_fixup_section(ctx, ctx->pctx->section);
 416         if (!ctx->pctx->package) {
 417                 if (!ctx->pctx->name)
 418                         uci_parse_error(ctx, "attempting to import a file without a package name");
 419
 420                 uci_switch_config(ctx);
 421         }
 422
 423         /* command string null-terminated by strtok */
 424         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 425
 426         ofs_type = next_arg(ctx, true, false, false);
 427         type = pctx_str(pctx, ofs_type);
 428         if (!uci_validate_type(type))
 429                 uci_parse_error(ctx, "invalid character in type field");
 430
 431         ofs_name = next_arg(ctx, false, true, false);
 432         type = pctx_str(pctx, ofs_type);
 433         name = pctx_str(pctx, ofs_name);
 434         assert_eol(ctx);
 435
 436         if (!name || !name[0]) {
 437                 ctx->internal = !pctx->merge;
 438                 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
 439         } else {
 440                 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
 441                 e = uci_lookup_list(&pctx->package->sections, name);
 442                 if (e)
 443                         ptr.s = uci_to_section(e);
 444                 ptr.section = name;
 445                 ptr.value = type;
 446
 447                 ctx->internal = !pctx->merge;
 448                 UCI_NESTED(uci_set, ctx, &ptr);
 449                 pctx->section = uci_to_section(ptr.last);
 450         }
 451 }
 452
 453 /*
 454  * parse the 'option' uci command (open a value)
 455  */
 456 static void uci_parse_option(struct uci_context *ctx, bool list)
 457 {
 458         struct uci_parse_context *pctx = ctx->pctx;
 459         struct uci_element *e;
 460         struct uci_ptr ptr;
 461         int ofs_name, ofs_value;
 462         char *name = NULL;
 463         char *value = NULL;
 464
 465         if (!pctx->section)
 466                 uci_parse_error(ctx, "option/list command found before the first section");
 467
 468         /* command string null-terminated by strtok */
 469         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 470
 471         ofs_name = next_arg(ctx, true, true, false);
 472         ofs_value = next_arg(ctx, false, false, false);
 473         name = pctx_str(pctx, ofs_name);
 474         value = pctx_str(pctx, ofs_value);
 475         assert_eol(ctx);
 476
 477         uci_fill_ptr(ctx, &ptr, &pctx->section->e);
 478         e = uci_lookup_list(&pctx->section->options, name);
 479         if (e)
 480                 ptr.o = uci_to_option(e);
 481         ptr.option = name;
 482         ptr.value = value;
 483
 484         ctx->internal = !pctx->merge;
 485         if (list)
 486                 UCI_NESTED(uci_add_list, ctx, &ptr);
 487         else
 488                 UCI_NESTED(uci_set, ctx, &ptr);
 489 }
 490
 491 /*
 492  * parse a complete input line, split up combined commands by ';'
 493  */
 494 static void uci_parse_line(struct uci_context *ctx, bool single)
 495 {
 496         struct uci_parse_context *pctx = ctx->pctx;
 497         char *word;
 498
 499         /* Skip whitespace characters at the start of line */
 500         skip_whitespace(ctx);
 501         do {
 502                 word = strtok(pctx_cur_str(pctx), " \t");
 503                 if (!word)
 504                         return;
 505
 506                 switch(word[0]) {
 507                         case 0:
 508                         case '#':
 509                                 return;
 510                         case 'p':
 511                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 512                                         uci_parse_package(ctx, single);
 513                                 else
 514                                         goto invalid;
 515                                 break;
 516                         case 'c':
 517                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 518                                         uci_parse_config(ctx);
 519                                 else
 520                                         goto invalid;
 521                                 break;
 522                         case 'o':
 523                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 524                                         uci_parse_option(ctx, false);
 525                                 else
 526                                         goto invalid;
 527                                 break;
 528                         case 'l':
 529                                 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
 530                                         uci_parse_option(ctx, true);
 531                                 else
 532                                         goto invalid;
 533                                 break;
 534                         default:
 535                                 goto invalid;
 536                 }
 537                 continue;
 538 invalid:
 539                 uci_parse_error(ctx, "invalid command");
 540         } while (1);
 541 }
 542
 543 /* max number of characters that escaping adds to the string */
 544 #define UCI_QUOTE_ESCAPE        "'\\''"
 545
 546 /*
 547  * escape an uci string for export
 548  */
 549 static const char *uci_escape(struct uci_context *ctx, const char *str)
 550 {
 551         const char *end;
 552         int ofs = 0;
 553
 554         if (!ctx->buf) {
 555                 ctx->bufsz = LINEBUF;
 556                 ctx->buf = malloc(LINEBUF);
 557
 558                 if (!ctx->buf)
 559                         return str;
 560         }
 561
 562         while (1) {
 563                 int len;
 564
 565                 end = strchr(str, '\'');
 566                 if (!end)
 567                         end = str + strlen(str);
 568                 len = end - str;
 569
 570                 /* make sure that we have enough room in the buffer */
 571                 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
 572                         ctx->bufsz *= 2;
 573                         ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
 574                 }
 575
 576                 /* copy the string until the character before the quote */
 577                 memcpy(&ctx->buf[ofs], str, len);
 578                 ofs += len;
 579
 580                 /* end of string? return the buffer */
 581                 if (*end == 0)
 582                         break;
 583
 584                 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
 585                 ofs += strlen(&ctx->buf[ofs]);
 586                 str = end + 1;
 587         }
 588
 589         ctx->buf[ofs] = 0;
 590         return ctx->buf;
 591 }
 592
 593 /*
 594  * export a single config package to a file stream
 595  */
 596 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 597 {
 598         struct uci_context *ctx = p->ctx;
 599         struct uci_element *s, *o, *i;
 600
 601         if (header)
 602                 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
 603         uci_foreach_element(&p->sections, s) {
 604                 struct uci_section *sec = uci_to_section(s);
 605                 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
 606                 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
 607                         fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 608                 fprintf(stream, "\n");
 609                 uci_foreach_element(&sec->options, o) {
 610                         struct uci_option *opt = uci_to_option(o);
 611                         switch(opt->type) {
 612                         case UCI_TYPE_STRING:
 613                                 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
 614                                 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
 615                                 break;
 616                         case UCI_TYPE_LIST:
 617                                 uci_foreach_element(&opt->v.list, i) {
 618                                         fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
 619                                         fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
 620                                 }
 621                                 break;
 622                         default:
 623                                 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
 624                                 break;
 625                         }
 626                 }
 627         }
 628         fprintf(stream, "\n");
 629 }
 630
 631 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 632 {
 633         struct uci_element *e;
 634
 635         UCI_HANDLE_ERR(ctx);
 636         UCI_ASSERT(ctx, stream != NULL);
 637
 638         if (package)
 639                 uci_export_package(package, stream, header);
 640         else {
 641                 uci_foreach_element(&ctx->root, e) {
 642                         uci_export_package(uci_to_package(e), stream, header);
 643                 }
 644         }
 645
 646         return 0;
 647 }
 648
 649 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 650 {
 651         struct uci_parse_context *pctx;
 652         UCI_HANDLE_ERR(ctx);
 653
 654         /* make sure no memory from previous parse attempts is leaked */
 655         uci_cleanup(ctx);
 656
 657         uci_alloc_parse_context(ctx);
 658         pctx = ctx->pctx;
 659         pctx->file = stream;
 660         if (package && *package && single) {
 661                 pctx->package = *package;
 662                 pctx->merge = true;
 663         }
 664
 665         /*
 666          * If 'name' was supplied, assume that the supplied stream does not contain
 667          * the appropriate 'package <name>' string to specify the config name
 668          * NB: the config file can still override the package name
 669          */
 670         if (name) {
 671                 UCI_ASSERT(ctx, uci_validate_package(name));
 672                 pctx->name = name;
 673         }
 674
 675         while (!feof(pctx->file)) {
 676                 pctx->pos = 0;
 677                 uci_getln(ctx, 0);
 678                 UCI_TRAP_SAVE(ctx, error);
 679                 if (pctx->buf[0])
 680                         uci_parse_line(ctx, single);
 681                 UCI_TRAP_RESTORE(ctx);
 682                 continue;
 683 error:
 684                 if (ctx->flags & UCI_FLAG_PERROR)
 685                         uci_perror(ctx, NULL);
 686                 if ((ctx->err != UCI_ERR_PARSE) ||
 687                         (ctx->flags & UCI_FLAG_STRICT))
 688                         UCI_THROW(ctx, ctx->err);
 689         }
 690
 691         uci_fixup_section(ctx, ctx->pctx->section);
 692         if (!pctx->package && name)
 693                 uci_switch_config(ctx);
 694         if (package)
 695                 *package = pctx->package;
 696         if (pctx->merge)
 697                 pctx->package = NULL;
 698
 699         pctx->name = NULL;
 700         uci_switch_config(ctx);
 701
 702         /* no error happened, we can get rid of the parser context now */
 703         uci_cleanup(ctx);
 704
 705         return 0;
 706 }
 707
 708
 709 static char *uci_config_path(struct uci_context *ctx, const char *name)
 710 {
 711         char *filename;
 712
 713         UCI_ASSERT(ctx, uci_validate_package(name));
 714         filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
 715         sprintf(filename, "%s/%s", ctx->confdir, name);
 716
 717         return filename;
 718 }
 719
 720 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 721 {
 722         struct uci_package *p = *package;
 723         FILE *f1, *f2 = NULL;
 724         char *name = NULL;
 725         char *path = NULL;
 726         char *filename = NULL;
 727         struct stat statbuf;
 728         bool do_rename = false;
 729
 730         if (!p->path) {
 731                 if (overwrite)
 732                         p->path = uci_config_path(ctx, p->e.name);
 733                 else
 734                         UCI_THROW(ctx, UCI_ERR_INVAL);
 735         }
 736
 737         if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
 738                 UCI_THROW(ctx, UCI_ERR_MEM);
 739
 740         if (!mktemp(filename))
 741                 *filename = 0;
 742
 743         if (!*filename) {
 744                 free(filename);
 745                 UCI_THROW(ctx, UCI_ERR_IO);
 746         }
 747
 748         if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
 749                 UCI_THROW(ctx, UCI_ERR_IO);
 750
 751         /* open the config file for writing now, so that it is locked */
 752         f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
 753
 754         /* flush unsaved changes and reload from delta file */
 755         UCI_TRAP_SAVE(ctx, done);
 756         if (p->has_delta) {
 757                 if (!overwrite) {
 758                         name = uci_strdup(ctx, p->e.name);
 759                         path = uci_strdup(ctx, p->path);
 760                         /* dump our own changes to the delta file */
 761                         if (!uci_list_empty(&p->delta))
 762                                 UCI_INTERNAL(uci_save, ctx, p);
 763
 764                         /*
 765                          * other processes might have modified the config
 766                          * as well. dump and reload
 767                          */
 768                         uci_free_package(&p);
 769                         uci_cleanup(ctx);
 770                         UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
 771
 772                         p->path = path;
 773                         p->has_delta = true;
 774                         *package = p;
 775
 776                         /* freed together with the uci_package */
 777                         path = NULL;
 778                 }
 779
 780                 /* flush delta */
 781                 if (!uci_load_delta(ctx, p, true))
 782                         goto done;
 783         }
 784
 785         f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
 786         uci_export(ctx, f2, p, false);
 787
 788         fflush(f2);
 789         fsync(fileno(f2));
 790         uci_close_stream(f2);
 791
 792         do_rename = true;
 793
 794         UCI_TRAP_RESTORE(ctx);
 795
 796 done:
 797         free(name);
 798         free(path);
 799         uci_close_stream(f1);
 800         if (do_rename && rename(filename, p->path)) {
 801                 unlink(filename);
 802                 UCI_THROW(ctx, UCI_ERR_IO);
 803         }
 804         free(filename);
 805         sync();
 806         if (ctx->err)
 807                 UCI_THROW(ctx, ctx->err);
 808 }
 809
 810
 811 /*
 812  * This function returns the filename by returning the string
 813  * after the last '/' character. By checking for a non-'\0'
 814  * character afterwards, directories are ignored (glob marks
 815  * those with a trailing '/'
 816  */
 817 static inline char *get_filename(char *path)
 818 {
 819         char *p;
 820
 821         p = strrchr(path, '/');
 822         p++;
 823         if (!*p)
 824                 return NULL;
 825         return p;
 826 }
 827
 828 static char **uci_list_config_files(struct uci_context *ctx)
 829 {
 830         char **configs;
 831         glob_t globbuf;
 832         int size, i;
 833         char *buf;
 834         char *dir;
 835
 836         dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
 837         sprintf(dir, "%s/*", ctx->confdir);
 838         if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
 839                 free(dir);
 840                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 841         }
 842
 843         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 844         for(i = 0; i < globbuf.gl_pathc; i++) {
 845                 char *p;
 846
 847                 p = get_filename(globbuf.gl_pathv[i]);
 848                 if (!p)
 849                         continue;
 850
 851                 size += strlen(p) + 1;
 852         }
 853
 854         configs = uci_malloc(ctx, size);
 855         buf = (char *) &configs[globbuf.gl_pathc + 1];
 856         for(i = 0; i < globbuf.gl_pathc; i++) {
 857                 char *p;
 858
 859                 p = get_filename(globbuf.gl_pathv[i]);
 860                 if (!p)
 861                         continue;
 862
 863                 if (!uci_validate_package(p))
 864                         continue;
 865
 866                 configs[i] = buf;
 867                 strcpy(buf, p);
 868                 buf += strlen(buf) + 1;
 869         }
 870         free(dir);
 871         globfree(&globbuf);
 872         return configs;
 873 }
 874
 875 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
 876 {
 877         struct uci_package *package = NULL;
 878         char *filename;
 879         bool confdir;
 880         FILE *file = NULL;
 881
 882         switch (name[0]) {
 883         case '.':
 884                 /* relative path outside of /etc/config */
 885                 if (name[1] != '/')
 886                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 887                 /* fall through */
 888         case '/':
 889                 /* absolute path outside of /etc/config */
 890                 filename = uci_strdup(ctx, name);
 891                 name = strrchr(name, '/') + 1;
 892                 confdir = false;
 893                 break;
 894         default:
 895                 /* config in /etc/config */
 896                 filename = uci_config_path(ctx, name);
 897                 confdir = true;
 898                 break;
 899         }
 900
 901         UCI_TRAP_SAVE(ctx, done);
 902         file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
 903         ctx->err = 0;
 904         UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
 905         UCI_TRAP_RESTORE(ctx);
 906
 907         if (package) {
 908                 package->path = filename;
 909                 package->has_delta = confdir;
 910                 uci_load_delta(ctx, package, false);
 911         }
 912
 913 done:
 914         uci_close_stream(file);
 915         if (ctx->err) {
 916                 free(filename);
 917                 UCI_THROW(ctx, ctx->err);
 918         }
 919         return package;
 920 }
 921
 922 __private UCI_BACKEND(uci_file_backend, "file",
 923         .load = uci_file_load,
 924         .commit = uci_file_commit,
 925         .list_configs = uci_list_config_files,
 926 );