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 General Public License for more details.
  13  */
  14
  15 /*
  16  * This file contains the code for parsing uci config files
  17  */
  18
  19 #include <sys/types.h>
  20 #include <sys/stat.h>
  21 #include <stdbool.h>
  22 #include <unistd.h>
  23 #include <fcntl.h>
  24 #include <stdio.h>
  25 #include <ctype.h>
  26
  27 #define LINEBUF 32
  28 #define LINEBUF_MAX     4096
  29
  30 static void uci_parse_error(struct uci_context *ctx, char *pos, char *reason)
  31 {
  32         struct uci_parse_context *pctx = ctx->pctx;
  33
  34         pctx->reason = reason;
  35         pctx->byte = pos - pctx->buf;
  36         UCI_THROW(ctx, UCI_ERR_PARSE);
  37 }
  38
  39 /*
  40  * Fetch a new line from the input stream and resize buffer if necessary
  41  */
  42 static void uci_getln(struct uci_context *ctx, int offset)
  43 {
  44         struct uci_parse_context *pctx = ctx->pctx;
  45         char *p;
  46         int ofs;
  47
  48         if (pctx->buf == NULL) {
  49                 pctx->buf = uci_malloc(ctx, LINEBUF);
  50                 pctx->bufsz = LINEBUF;
  51         }
  52
  53         ofs = offset;
  54         do {
  55                 p = &pctx->buf[ofs];
  56                 p[ofs] = 0;
  57
  58                 p = fgets(p, pctx->bufsz - ofs, pctx->file);
  59                 if (!p || !*p)
  60                         return;
  61
  62                 ofs += strlen(p);
  63                 if (pctx->buf[ofs - 1] == '\n') {
  64                         pctx->line++;
  65                         pctx->buf[ofs - 1] = 0;
  66                         return;
  67                 }
  68
  69                 if (pctx->bufsz > LINEBUF_MAX/2)
  70                         uci_parse_error(ctx, p, "line too long");
  71
  72                 pctx->bufsz *= 2;
  73                 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
  74         } while (1);
  75 }
  76
  77 /*
  78  * Clean up all extra memory used by the parser and exporter
  79  */
  80 static void uci_file_cleanup(struct uci_context *ctx)
  81 {
  82         struct uci_parse_context *pctx;
  83
  84         if (ctx->buf) {
  85                 free(ctx->buf);
  86                 ctx->buf = NULL;
  87                 ctx->bufsz = 0;
  88         }
  89
  90         pctx = ctx->pctx;
  91         if (!pctx)
  92                 return;
  93
  94         ctx->pctx = NULL;
  95         if (pctx->package)
  96                 uci_free_package(&pctx->package);
  97
  98         if (pctx->buf)
  99                 free(pctx->buf);
 100
 101         free(pctx);
 102 }
 103
 104 /*
 105  * parse a character escaped by '\'
 106  * returns true if the escaped character is to be parsed
 107  * returns false if the escaped character is to be ignored
 108  */
 109 static inline bool parse_backslash(struct uci_context *ctx, char **str)
 110 {
 111         /* skip backslash */
 112         *str += 1;
 113
 114         /* undecoded backslash at the end of line, fetch the next line */
 115         if (!**str) {
 116                 *str += 1;
 117                 uci_getln(ctx, *str - ctx->pctx->buf);
 118                 return false;
 119         }
 120
 121         /* FIXME: decode escaped char, necessary? */
 122         return true;
 123 }
 124
 125 /*
 126  * move the string pointer forward until a non-whitespace character or
 127  * EOL is reached
 128  */
 129 static void skip_whitespace(struct uci_context *ctx, char **str)
 130 {
 131 restart:
 132         while (**str && isspace(**str))
 133                 *str += 1;
 134
 135         if (**str == '\\') {
 136                 if (!parse_backslash(ctx, str))
 137                         goto restart;
 138         }
 139 }
 140
 141 static inline void addc(char **dest, char **src)
 142 {
 143         **dest = **src;
 144         *dest += 1;
 145         *src += 1;
 146 }
 147
 148 /*
 149  * parse a double quoted string argument from the command line
 150  */
 151 static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
 152 {
 153         char c;
 154
 155         /* skip quote character */
 156         *str += 1;
 157
 158         while ((c = **str)) {
 159                 switch(c) {
 160                 case '"':
 161                         **target = 0;
 162                         *str += 1;
 163                         return;
 164                 case '\\':
 165                         if (!parse_backslash(ctx, str))
 166                                 continue;
 167                         /* fall through */
 168                 default:
 169                         addc(target, str);
 170                         break;
 171                 }
 172         }
 173         uci_parse_error(ctx, *str, "unterminated \"");
 174 }
 175
 176 /*
 177  * parse a single quoted string argument from the command line
 178  */
 179 static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
 180 {
 181         char c;
 182         /* skip quote character */
 183         *str += 1;
 184
 185         while ((c = **str)) {
 186                 switch(c) {
 187                 case '\'':
 188                         **target = 0;
 189                         *str += 1;
 190                         return;
 191                 default:
 192                         addc(target, str);
 193                 }
 194         }
 195         uci_parse_error(ctx, *str, "unterminated '");
 196 }
 197
 198 /*
 199  * parse a string from the command line and detect the quoting style
 200  */
 201 static void parse_str(struct uci_context *ctx, char **str, char **target)
 202 {
 203         do {
 204                 switch(**str) {
 205                 case '\'':
 206                         parse_single_quote(ctx, str, target);
 207                         break;
 208                 case '"':
 209                         parse_double_quote(ctx, str, target);
 210                         break;
 211                 case 0:
 212                         goto done;
 213                 case '\\':
 214                         if (!parse_backslash(ctx, str))
 215                                 continue;
 216                         /* fall through */
 217                 default:
 218                         addc(target, str);
 219                         break;
 220                 }
 221         } while (**str && !isspace(**str));
 222 done:
 223
 224         /*
 225          * if the string was unquoted and we've stopped at a whitespace
 226          * character, skip to the next one, because the whitespace will
 227          * be overwritten by a null byte here
 228          */
 229         if (**str)
 230                 *str += 1;
 231
 232         /* terminate the parsed string */
 233         **target = 0;
 234 }
 235
 236 /*
 237  * extract the next argument from the command line
 238  */
 239 static char *next_arg(struct uci_context *ctx, char **str, bool required, bool name)
 240 {
 241         char *val;
 242         char *ptr;
 243
 244         val = ptr = *str;
 245         skip_whitespace(ctx, str);
 246         parse_str(ctx, str, &ptr);
 247         if (!*val) {
 248                 if (required)
 249                         uci_parse_error(ctx, *str, "insufficient arguments");
 250                 goto done;
 251         }
 252
 253         if (name && !uci_validate_name(val))
 254                 uci_parse_error(ctx, val, "invalid character in field");
 255
 256 done:
 257         return val;
 258 }
 259
 260 /*
 261  * verify that the end of the line or command is reached.
 262  * throw an error if extra arguments are given on the command line
 263  */
 264 static void assert_eol(struct uci_context *ctx, char **str)
 265 {
 266         char *tmp;
 267
 268         tmp = next_arg(ctx, str, false, false);
 269         if (tmp && *tmp)
 270                 uci_parse_error(ctx, *str, "too many arguments");
 271 }
 272
 273 /*
 274  * switch to a different config, either triggered by uci_load, or by a
 275  * 'package <...>' statement in the import file
 276  */
 277 static void uci_switch_config(struct uci_context *ctx)
 278 {
 279         struct uci_parse_context *pctx;
 280         struct uci_element *e;
 281         const char *name;
 282
 283         pctx = ctx->pctx;
 284         name = pctx->name;
 285
 286         /* add the last config to main config file list */
 287         if (pctx->package) {
 288                 uci_list_add(&ctx->root, &pctx->package->e.list);
 289
 290                 pctx->package = NULL;
 291                 pctx->section = NULL;
 292         }
 293
 294         if (!name)
 295                 return;
 296
 297         /*
 298          * if an older config under the same name exists, unload it
 299          * ignore errors here, e.g. if the config was not found
 300          */
 301         e = uci_lookup_list(ctx, &ctx->root, name);
 302         if (e)
 303                 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 304         pctx->package = uci_alloc_package(ctx, name);
 305 }
 306
 307 /*
 308  * parse the 'package' uci command (next config package)
 309  */
 310 static void uci_parse_package(struct uci_context *ctx, char **str, bool single)
 311 {
 312         char *name = NULL;
 313
 314         /* command string null-terminated by strtok */
 315         *str += strlen(*str) + 1;
 316
 317         name = next_arg(ctx, str, true, true);
 318         assert_eol(ctx, str);
 319         if (single)
 320                 return;
 321
 322         ctx->pctx->name = name;
 323         uci_switch_config(ctx);
 324 }
 325
 326 /* Based on an efficient hash function published by D. J. Bernstein */
 327 static unsigned int djbhash(unsigned int hash, char *str)
 328 {
 329         int len = strlen(str);
 330         int i;
 331
 332         /* initial value */
 333         if (hash == ~0)
 334                 hash = 5381;
 335
 336         for(i = 0; i < len; i++) {
 337                 hash = ((hash << 5) + hash) + str[i];
 338         }
 339         return (hash & 0x7FFFFFFF);
 340 }
 341
 342 /* fix up an unnamed section */
 343 static void uci_fixup_section(struct uci_context *ctx, struct uci_section *s)
 344 {
 345         unsigned int hash = ~0;
 346         struct uci_element *e;
 347         char buf[16];
 348
 349         if (!s || s->e.name)
 350                 return;
 351
 352         /*
 353          * Generate a name for unnamed sections. This is used as reference
 354          * when locating or updating the section from apps/scripts.
 355          * To make multiple concurrent versions somewhat safe for updating,
 356          * the name is generated from a hash of its type and name/value
 357          * pairs of its option, and it is prefixed by a counter value.
 358          * If the order of the unnamed sections changes for some reason,
 359          * updates to them will be rejected.
 360          */
 361         hash = djbhash(hash, s->type);
 362         uci_foreach_element(&s->options, e) {
 363                 hash = djbhash(hash, e->name);
 364                 hash = djbhash(hash, uci_to_option(e)->value);
 365         }
 366         sprintf(buf, "cfg%02x%04x", ++s->package->n_section, hash % (1 << 16));
 367         s->e.name = uci_strdup(ctx, buf);
 368 }
 369
 370 /*
 371  * parse the 'config' uci command (open a section)
 372  */
 373 static void uci_parse_config(struct uci_context *ctx, char **str)
 374 {
 375         struct uci_section *s;
 376         char *name = NULL;
 377         char *type = NULL;
 378
 379         uci_fixup_section(ctx, ctx->pctx->section);
 380         if (!ctx->pctx->package) {
 381                 if (!ctx->pctx->name)
 382                         uci_parse_error(ctx, *str, "attempting to import a file without a package name");
 383
 384                 uci_switch_config(ctx);
 385         }
 386
 387         /* command string null-terminated by strtok */
 388         *str += strlen(*str) + 1;
 389
 390         type = next_arg(ctx, str, true, true);
 391         name = next_arg(ctx, str, false, true);
 392         assert_eol(ctx, str);
 393         ctx->pctx->section = uci_alloc_section(ctx->pctx->package, type, name);
 394 }
 395
 396 /*
 397  * parse the 'option' uci command (open a value)
 398  */
 399 static void uci_parse_option(struct uci_context *ctx, char **str)
 400 {
 401         char *name = NULL;
 402         char *value = NULL;
 403
 404         if (!ctx->pctx->section)
 405                 uci_parse_error(ctx, *str, "option command found before the first section");
 406
 407         /* command string null-terminated by strtok */
 408         *str += strlen(*str) + 1;
 409
 410         name = next_arg(ctx, str, true, true);
 411         value = next_arg(ctx, str, true, false);
 412         assert_eol(ctx, str);
 413         uci_alloc_option(ctx->pctx->section, name, value);
 414 }
 415
 416
 417 /*
 418  * parse a complete input line, split up combined commands by ';'
 419  */
 420 static void uci_parse_line(struct uci_context *ctx, bool single)
 421 {
 422         struct uci_parse_context *pctx = ctx->pctx;
 423         char *word, *brk = NULL;
 424
 425         for (word = strtok_r(pctx->buf, ";", &brk);
 426                  word;
 427                  word = strtok_r(NULL, ";", &brk)) {
 428
 429                 char *pbrk = NULL;
 430                 word = strtok_r(word, " \t", &pbrk);
 431
 432                 switch(word[0]) {
 433                         case 'p':
 434                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 435                                         uci_parse_package(ctx, &word, single);
 436                                 break;
 437                         case 'c':
 438                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 439                                         uci_parse_config(ctx, &word);
 440                                 break;
 441                         case 'o':
 442                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 443                                         uci_parse_option(ctx, &word);
 444                                 break;
 445                         default:
 446                                 uci_parse_error(ctx, word, "unterminated command");
 447                                 break;
 448                 }
 449         }
 450 }
 451
 452 /* max number of characters that escaping adds to the string */
 453 #define UCI_QUOTE_ESCAPE        "'\\''"
 454
 455 /*
 456  * escape an uci string for export
 457  */
 458 static char *uci_escape(struct uci_context *ctx, char *str)
 459 {
 460         char *s, *p;
 461         int pos = 0;
 462
 463         if (!ctx->buf) {
 464                 ctx->bufsz = LINEBUF;
 465                 ctx->buf = malloc(LINEBUF);
 466         }
 467
 468         s = str;
 469         p = strchr(str, '\'');
 470         if (!p)
 471                 return str;
 472
 473         do {
 474                 int len = p - s;
 475                 if (len > 0) {
 476                         if (p + sizeof(UCI_QUOTE_ESCAPE) - str >= ctx->bufsz) {
 477                                 ctx->bufsz *= 2;
 478                                 ctx->buf = realloc(ctx->buf, ctx->bufsz);
 479                                 if (!ctx->buf)
 480                                         UCI_THROW(ctx, UCI_ERR_MEM);
 481                         }
 482                         memcpy(&ctx->buf[pos], s, len);
 483                         pos += len;
 484                 }
 485                 strcpy(&ctx->buf[pos], UCI_QUOTE_ESCAPE);
 486                 pos += sizeof(UCI_QUOTE_ESCAPE);
 487                 s = p + 1;
 488         } while ((p = strchr(s, '\'')));
 489
 490         return ctx->buf;
 491 }
 492
 493
 494 /*
 495  * export a single config package to a file stream
 496  */
 497 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 498 {
 499         struct uci_context *ctx = p->ctx;
 500         struct uci_element *s, *o;
 501
 502         if (header)
 503                 fprintf(stream, "package '%s'\n", uci_escape(ctx, p->e.name));
 504         uci_foreach_element(&p->sections, s) {
 505                 struct uci_section *sec = uci_to_section(s);
 506                 fprintf(stream, "\nconfig '%s'", uci_escape(ctx, sec->type));
 507                 if (!sec->anonymous)
 508                         fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 509                 fprintf(stream, "\n");
 510                 uci_foreach_element(&sec->options, o) {
 511                         struct uci_option *opt = uci_to_option(o);
 512                         fprintf(stream, "\toption '%s'", uci_escape(ctx, opt->e.name));
 513                         fprintf(stream, " '%s'\n", uci_escape(ctx, opt->value));
 514                 }
 515         }
 516         fprintf(stream, "\n");
 517 }
 518
 519 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 520 {
 521         struct uci_element *e;
 522
 523         UCI_HANDLE_ERR(ctx);
 524         UCI_ASSERT(ctx, stream != NULL);
 525
 526         if (package)
 527                 uci_export_package(package, stream, header);
 528         else {
 529                 uci_foreach_element(&ctx->root, e) {
 530                         uci_export_package(uci_to_package(e), stream, header);
 531                 }
 532         }
 533
 534         return 0;
 535 }
 536
 537 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 538 {
 539         struct uci_parse_context *pctx;
 540
 541         /* make sure no memory from previous parse attempts is leaked */
 542         uci_file_cleanup(ctx);
 543
 544         pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
 545         ctx->pctx = pctx;
 546         pctx->file = stream;
 547
 548         /*
 549          * If 'name' was supplied, assume that the supplied stream does not contain
 550          * the appropriate 'package <name>' string to specify the config name
 551          * NB: the config file can still override the package name
 552          */
 553         if (name)
 554                 pctx->name = name;
 555
 556         while (!feof(pctx->file)) {
 557                 uci_getln(ctx, 0);
 558                 UCI_TRAP_SAVE(ctx, error);
 559                 if (pctx->buf[0])
 560                         uci_parse_line(ctx, single);
 561                 UCI_TRAP_RESTORE(ctx);
 562                 continue;
 563 error:
 564                 if (ctx->flags & UCI_FLAG_PERROR)
 565                         uci_perror(ctx, NULL);
 566                 if ((ctx->errno != UCI_ERR_PARSE) ||
 567                         (ctx->flags & UCI_FLAG_STRICT))
 568                         UCI_THROW(ctx, ctx->errno);
 569         }
 570
 571         uci_fixup_section(ctx, ctx->pctx->section);
 572         if (package)
 573                 *package = pctx->package;
 574
 575         pctx->name = NULL;
 576         uci_switch_config(ctx);
 577
 578         /* no error happened, we can get rid of the parser context now */
 579         uci_file_cleanup(ctx);
 580
 581         return 0;
 582 }
 583
 584 /*
 585  * open a stream and go to the right position
 586  *
 587  * note: when opening for write and seeking to the beginning of
 588  * the stream, truncate the file
 589  */
 590 static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int pos, bool write, bool create)
 591 {
 592         struct stat statbuf;
 593         FILE *file = NULL;
 594         int fd, ret;
 595         int mode = (write ? O_RDWR : O_RDONLY);
 596
 597         if (create)
 598                 mode |= O_CREAT;
 599
 600         if (!write && ((stat(filename, &statbuf) < 0) ||
 601                 ((statbuf.st_mode &  S_IFMT) != S_IFREG))) {
 602                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 603         }
 604
 605         fd = open(filename, mode, UCI_FILEMODE);
 606         if (fd <= 0)
 607                 goto error;
 608
 609         if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)
 610                 goto error;
 611
 612         ret = lseek(fd, 0, pos);
 613
 614         if (ret < 0)
 615                 goto error;
 616
 617         file = fdopen(fd, (write ? "w+" : "r"));
 618         if (file)
 619                 goto done;
 620
 621 error:
 622         UCI_THROW(ctx, UCI_ERR_IO);
 623 done:
 624         return file;
 625 }
 626
 627 static void uci_close_stream(FILE *stream)
 628 {
 629         int fd;
 630
 631         if (!stream)
 632                 return;
 633
 634         fd = fileno(stream);
 635         flock(fd, LOCK_UN);
 636         fclose(stream);
 637 }
 638
 639 static void uci_parse_history_line(struct uci_context *ctx, struct uci_package *p, char *buf)
 640 {
 641         bool delete = false;
 642         bool rename = false;
 643         char *package = NULL;
 644         char *section = NULL;
 645         char *option = NULL;
 646         char *value = NULL;
 647
 648         if (buf[0] == '-') {
 649                 delete = true;
 650                 buf++;
 651         } else if (buf[0] == '@') {
 652                 rename = true;
 653                 buf++;
 654         }
 655
 656         UCI_INTERNAL(uci_parse_tuple, ctx, buf, &package, &section, &option, &value);
 657         if (!package || !section || (!delete && !value))
 658                 goto error;
 659         if (strcmp(package, p->e.name) != 0)
 660                 goto error;
 661         if (!uci_validate_name(section))
 662                 goto error;
 663         if (option && !uci_validate_name(option))
 664                 goto error;
 665
 666         if (rename)
 667                 UCI_INTERNAL(uci_rename, ctx, p, section, option, value);
 668         else if (delete)
 669                 UCI_INTERNAL(uci_delete, ctx, p, section, option);
 670         else
 671                 UCI_INTERNAL(uci_set, ctx, p, section, option, value);
 672
 673         return;
 674 error:
 675         UCI_THROW(ctx, UCI_ERR_PARSE);
 676 }
 677
 678 static void uci_parse_history(struct uci_context *ctx, FILE *stream, struct uci_package *p)
 679 {
 680         struct uci_parse_context *pctx;
 681
 682         /* make sure no memory from previous parse attempts is leaked */
 683         uci_file_cleanup(ctx);
 684
 685         pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
 686         ctx->pctx = pctx;
 687         pctx->file = stream;
 688
 689         while (!feof(pctx->file)) {
 690                 uci_getln(ctx, 0);
 691                 if (!pctx->buf[0])
 692                         continue;
 693
 694                 /*
 695                  * ignore parse errors in single lines, we want to preserve as much
 696                  * history as possible
 697                  */
 698                 UCI_TRAP_SAVE(ctx, error);
 699                 uci_parse_history_line(ctx, p, pctx->buf);
 700                 UCI_TRAP_RESTORE(ctx);
 701 error:
 702                 continue;
 703         }
 704
 705         /* no error happened, we can get rid of the parser context now */
 706         uci_file_cleanup(ctx);
 707 }
 708
 709 static void uci_load_history(struct uci_context *ctx, struct uci_package *p, bool flush)
 710 {
 711         char *filename = NULL;
 712         FILE *f = NULL;
 713
 714         if (!p->confdir)
 715                 return;
 716         if ((asprintf(&filename, "%s/%s", UCI_SAVEDIR, p->e.name) < 0) || !filename)
 717                 UCI_THROW(ctx, UCI_ERR_MEM);
 718
 719         UCI_TRAP_SAVE(ctx, done);
 720         f = uci_open_stream(ctx, filename, SEEK_SET, flush, false);
 721         uci_parse_history(ctx, f, p);
 722         UCI_TRAP_RESTORE(ctx);
 723
 724 done:
 725         if (flush && f) {
 726                 rewind(f);
 727                 ftruncate(fileno(f), 0);
 728         }
 729         if (filename)
 730                 free(filename);
 731         uci_close_stream(f);
 732         ctx->errno = 0;
 733 }
 734
 735
 736 int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
 737 {
 738         char *filename;
 739         bool confdir;
 740         FILE *file = NULL;
 741
 742         UCI_HANDLE_ERR(ctx);
 743         UCI_ASSERT(ctx, name != NULL);
 744
 745         switch (name[0]) {
 746         case '.':
 747                 /* relative path outside of /etc/config */
 748                 if (name[1] != '/')
 749                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 750                 /* fall through */
 751         case '/':
 752                 /* absolute path outside of /etc/config */
 753                 filename = uci_strdup(ctx, name);
 754                 name = strrchr(name, '/') + 1;
 755                 confdir = false;
 756                 break;
 757         default:
 758                 /* config in /etc/config */
 759                 if (strchr(name, '/'))
 760                         UCI_THROW(ctx, UCI_ERR_INVAL);
 761                 filename = uci_malloc(ctx, strlen(name) + sizeof(UCI_CONFDIR) + 2);
 762                 sprintf(filename, UCI_CONFDIR "/%s", name);
 763                 confdir = true;
 764                 break;
 765         }
 766
 767         file = uci_open_stream(ctx, filename, SEEK_SET, false, false);
 768         ctx->errno = 0;
 769         UCI_TRAP_SAVE(ctx, done);
 770         uci_import(ctx, file, name, package, true);
 771         UCI_TRAP_RESTORE(ctx);
 772
 773         if (*package) {
 774                 (*package)->path = filename;
 775                 (*package)->confdir = confdir;
 776                 uci_load_history(ctx, *package, false);
 777         }
 778
 779 done:
 780         uci_close_stream(file);
 781         return ctx->errno;
 782 }
 783
 784 int uci_save(struct uci_context *ctx, struct uci_package *p)
 785 {
 786         FILE *f = NULL;
 787         char *filename = NULL;
 788         struct uci_element *e, *tmp;
 789
 790         UCI_HANDLE_ERR(ctx);
 791         UCI_ASSERT(ctx, p != NULL);
 792
 793         /*
 794          * if the config file was outside of the /etc/config path,
 795          * don't save the history to a file, update the real file
 796          * directly.
 797          * does not modify the uci_package pointer
 798          */
 799         if (!p->confdir)
 800                 return uci_commit(ctx, &p);
 801
 802         if (uci_list_empty(&p->history))
 803                 return 0;
 804
 805         if ((asprintf(&filename, "%s/%s", UCI_SAVEDIR, p->e.name) < 0) || !filename)
 806                 UCI_THROW(ctx, UCI_ERR_MEM);
 807
 808         ctx->errno = 0;
 809         UCI_TRAP_SAVE(ctx, done);
 810         f = uci_open_stream(ctx, filename, SEEK_END, true, true);
 811         UCI_TRAP_RESTORE(ctx);
 812
 813         uci_foreach_element_safe(&p->history, tmp, e) {
 814                 struct uci_history *h = uci_to_history(e);
 815
 816                 if (h->cmd == UCI_CMD_REMOVE)
 817                         fprintf(f, "-");
 818                 else if (h->cmd == UCI_CMD_RENAME)
 819                         fprintf(f, "@");
 820
 821                 fprintf(f, "%s.%s", p->e.name, h->section);
 822                 if (e->name)
 823                         fprintf(f, ".%s", e->name);
 824
 825                 if (h->cmd == UCI_CMD_REMOVE)
 826                         fprintf(f, "\n");
 827                 else
 828                         fprintf(f, "=%s\n", h->value);
 829                 uci_free_history(h);
 830         }
 831
 832 done:
 833         uci_close_stream(f);
 834         if (filename)
 835                 free(filename);
 836         if (ctx->errno)
 837                 UCI_THROW(ctx, ctx->errno);
 838
 839         return 0;
 840 }
 841
 842 int uci_commit(struct uci_context *ctx, struct uci_package **package)
 843 {
 844         struct uci_package *p;
 845         FILE *f = NULL;
 846         char *name = NULL;
 847         char *path = NULL;
 848
 849         UCI_HANDLE_ERR(ctx);
 850         UCI_ASSERT(ctx, package != NULL);
 851         p = *package;
 852
 853         UCI_ASSERT(ctx, p != NULL);
 854         UCI_ASSERT(ctx, p->path != NULL);
 855
 856         /* open the config file for writing now, so that it is locked */
 857         f = uci_open_stream(ctx, p->path, SEEK_SET, true, true);
 858
 859         /* flush unsaved changes and reload from history file */
 860         UCI_TRAP_SAVE(ctx, done);
 861         if (p->confdir) {
 862                 name = uci_strdup(ctx, p->e.name);
 863                 path = uci_strdup(ctx, p->path);
 864                 if (!uci_list_empty(&p->history))
 865                         UCI_INTERNAL(uci_save, ctx, p);
 866                 uci_free_package(&p);
 867                 uci_file_cleanup(ctx);
 868                 UCI_INTERNAL(uci_import, ctx, f, name, &p, true);
 869
 870                 p->path = path;
 871                 p->confdir = true;
 872                 *package = p;
 873
 874                 /* freed together with the uci_package */
 875                 path = NULL;
 876
 877                 /* check for updated history, just in case */
 878                 uci_load_history(ctx, p, true);
 879         }
 880
 881         rewind(f);
 882         ftruncate(fileno(f), 0);
 883
 884         uci_export(ctx, f, p, false);
 885         UCI_TRAP_RESTORE(ctx);
 886
 887 done:
 888         if (name)
 889                 free(name);
 890         if (path)
 891                 free(path);
 892         uci_close_stream(f);
 893         if (ctx->errno)
 894                 UCI_THROW(ctx, ctx->errno);
 895
 896         return 0;
 897 }
 898
 899
 900 /*
 901  * This function returns the filename by returning the string
 902  * after the last '/' character. By checking for a non-'\0'
 903  * character afterwards, directories are ignored (glob marks
 904  * those with a trailing '/'
 905  */
 906 static inline char *get_filename(char *path)
 907 {
 908         char *p;
 909
 910         p = strrchr(path, '/');
 911         p++;
 912         if (!*p)
 913                 return NULL;
 914         return p;
 915 }
 916
 917 int uci_list_configs(struct uci_context *ctx, char ***list)
 918 {
 919         char **configs;
 920         glob_t globbuf;
 921         int size, i;
 922         char *buf;
 923
 924         UCI_HANDLE_ERR(ctx);
 925
 926         if (glob(UCI_CONFDIR "/*", GLOB_MARK, NULL, &globbuf) != 0)
 927                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 928
 929         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 930         for(i = 0; i < globbuf.gl_pathc; i++) {
 931                 char *p;
 932
 933                 p = get_filename(globbuf.gl_pathv[i]);
 934                 if (!p)
 935                         continue;
 936
 937                 size += strlen(p) + 1;
 938         }
 939
 940         configs = uci_malloc(ctx, size);
 941         buf = (char *) &configs[globbuf.gl_pathc + 1];
 942         for(i = 0; i < globbuf.gl_pathc; i++) {
 943                 char *p;
 944
 945                 p = get_filename(globbuf.gl_pathv[i]);
 946                 if (!p)
 947                         continue;
 948
 949                 configs[i] = buf;
 950                 strcpy(buf, p);
 951                 buf += strlen(buf) + 1;
 952         }
 953         *list = configs;
 954
 955         return 0;
 956 }
 957