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_parse_context *pctx = ctx->pctx;
 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
 394         if (pctx->merge) {
 395                 UCI_TRAP_SAVE(ctx, error);
 396                 uci_set(ctx, pctx->package, name, NULL, type);
 397                 UCI_TRAP_RESTORE(ctx);
 398                 return;
 399 error:
 400                 UCI_THROW(ctx, ctx->errno);
 401         } else
 402                 pctx->section = uci_alloc_section(pctx->package, type, name);
 403 }
 404
 405 /*
 406  * parse the 'option' uci command (open a value)
 407  */
 408 static void uci_parse_option(struct uci_context *ctx, char **str)
 409 {
 410         struct uci_parse_context *pctx = ctx->pctx;
 411         char *name = NULL;
 412         char *value = NULL;
 413
 414         if (!pctx->section)
 415                 uci_parse_error(ctx, *str, "option command found before the first section");
 416
 417         /* command string null-terminated by strtok */
 418         *str += strlen(*str) + 1;
 419
 420         name = next_arg(ctx, str, true, true);
 421         value = next_arg(ctx, str, true, false);
 422         assert_eol(ctx, str);
 423
 424         if (pctx->merge) {
 425                 UCI_TRAP_SAVE(ctx, error);
 426                 uci_set(ctx, pctx->package, pctx->section->e.name, name, value);
 427                 UCI_TRAP_RESTORE(ctx);
 428                 return;
 429 error:
 430                 UCI_THROW(ctx, ctx->errno);
 431         } else
 432                 uci_alloc_option(pctx->section, name, value);
 433 }
 434
 435
 436 /*
 437  * parse a complete input line, split up combined commands by ';'
 438  */
 439 static void uci_parse_line(struct uci_context *ctx, bool single)
 440 {
 441         struct uci_parse_context *pctx = ctx->pctx;
 442         char *word, *brk = NULL;
 443
 444         for (word = strtok_r(pctx->buf, ";", &brk);
 445                  word;
 446                  word = strtok_r(NULL, ";", &brk)) {
 447
 448                 char *pbrk = NULL;
 449                 word = strtok_r(word, " \t", &pbrk);
 450
 451                 switch(word[0]) {
 452                         case 'p':
 453                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 454                                         uci_parse_package(ctx, &word, single);
 455                                 break;
 456                         case 'c':
 457                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 458                                         uci_parse_config(ctx, &word);
 459                                 break;
 460                         case 'o':
 461                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 462                                         uci_parse_option(ctx, &word);
 463                                 break;
 464                         default:
 465                                 uci_parse_error(ctx, word, "unterminated command");
 466                                 break;
 467                 }
 468         }
 469 }
 470
 471 /* max number of characters that escaping adds to the string */
 472 #define UCI_QUOTE_ESCAPE        "'\\''"
 473
 474 /*
 475  * escape an uci string for export
 476  */
 477 static char *uci_escape(struct uci_context *ctx, char *str)
 478 {
 479         char *s, *p;
 480         int pos = 0;
 481
 482         if (!ctx->buf) {
 483                 ctx->bufsz = LINEBUF;
 484                 ctx->buf = malloc(LINEBUF);
 485         }
 486
 487         s = str;
 488         p = strchr(str, '\'');
 489         if (!p)
 490                 return str;
 491
 492         do {
 493                 int len = p - s;
 494                 if (len > 0) {
 495                         if (p + sizeof(UCI_QUOTE_ESCAPE) - str >= ctx->bufsz) {
 496                                 ctx->bufsz *= 2;
 497                                 ctx->buf = realloc(ctx->buf, ctx->bufsz);
 498                                 if (!ctx->buf)
 499                                         UCI_THROW(ctx, UCI_ERR_MEM);
 500                         }
 501                         memcpy(&ctx->buf[pos], s, len);
 502                         pos += len;
 503                 }
 504                 strcpy(&ctx->buf[pos], UCI_QUOTE_ESCAPE);
 505                 pos += sizeof(UCI_QUOTE_ESCAPE);
 506                 s = p + 1;
 507         } while ((p = strchr(s, '\'')));
 508
 509         return ctx->buf;
 510 }
 511
 512
 513 /*
 514  * export a single config package to a file stream
 515  */
 516 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 517 {
 518         struct uci_context *ctx = p->ctx;
 519         struct uci_element *s, *o;
 520
 521         if (header)
 522                 fprintf(stream, "package '%s'\n", uci_escape(ctx, p->e.name));
 523         uci_foreach_element(&p->sections, s) {
 524                 struct uci_section *sec = uci_to_section(s);
 525                 fprintf(stream, "\nconfig '%s'", uci_escape(ctx, sec->type));
 526                 if (!sec->anonymous)
 527                         fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 528                 fprintf(stream, "\n");
 529                 uci_foreach_element(&sec->options, o) {
 530                         struct uci_option *opt = uci_to_option(o);
 531                         fprintf(stream, "\toption '%s'", uci_escape(ctx, opt->e.name));
 532                         fprintf(stream, " '%s'\n", uci_escape(ctx, opt->value));
 533                 }
 534         }
 535         fprintf(stream, "\n");
 536 }
 537
 538 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 539 {
 540         struct uci_element *e;
 541
 542         UCI_HANDLE_ERR(ctx);
 543         UCI_ASSERT(ctx, stream != NULL);
 544
 545         if (package)
 546                 uci_export_package(package, stream, header);
 547         else {
 548                 uci_foreach_element(&ctx->root, e) {
 549                         uci_export_package(uci_to_package(e), stream, header);
 550                 }
 551         }
 552
 553         return 0;
 554 }
 555
 556 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 557 {
 558         struct uci_parse_context *pctx;
 559         UCI_HANDLE_ERR(ctx);
 560
 561         /* make sure no memory from previous parse attempts is leaked */
 562         uci_file_cleanup(ctx);
 563
 564         pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
 565         ctx->pctx = pctx;
 566         pctx->file = stream;
 567         if (*package && single) {
 568                 pctx->package = *package;
 569                 pctx->merge = true;
 570         }
 571
 572         /*
 573          * If 'name' was supplied, assume that the supplied stream does not contain
 574          * the appropriate 'package <name>' string to specify the config name
 575          * NB: the config file can still override the package name
 576          */
 577         if (name)
 578                 pctx->name = name;
 579
 580         while (!feof(pctx->file)) {
 581                 uci_getln(ctx, 0);
 582                 UCI_TRAP_SAVE(ctx, error);
 583                 if (pctx->buf[0])
 584                         uci_parse_line(ctx, single);
 585                 UCI_TRAP_RESTORE(ctx);
 586                 continue;
 587 error:
 588                 if (ctx->flags & UCI_FLAG_PERROR)
 589                         uci_perror(ctx, NULL);
 590                 if ((ctx->errno != UCI_ERR_PARSE) ||
 591                         (ctx->flags & UCI_FLAG_STRICT))
 592                         UCI_THROW(ctx, ctx->errno);
 593         }
 594
 595         uci_fixup_section(ctx, ctx->pctx->section);
 596         if (package)
 597                 *package = pctx->package;
 598         if (pctx->merge)
 599                 pctx->package = NULL;
 600
 601         pctx->name = NULL;
 602         uci_switch_config(ctx);
 603
 604         /* no error happened, we can get rid of the parser context now */
 605         uci_file_cleanup(ctx);
 606
 607         return 0;
 608 }
 609
 610 /*
 611  * open a stream and go to the right position
 612  *
 613  * note: when opening for write and seeking to the beginning of
 614  * the stream, truncate the file
 615  */
 616 static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int pos, bool write, bool create)
 617 {
 618         struct stat statbuf;
 619         FILE *file = NULL;
 620         int fd, ret;
 621         int mode = (write ? O_RDWR : O_RDONLY);
 622
 623         if (create)
 624                 mode |= O_CREAT;
 625
 626         if (!write && ((stat(filename, &statbuf) < 0) ||
 627                 ((statbuf.st_mode &  S_IFMT) != S_IFREG))) {
 628                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 629         }
 630
 631         fd = open(filename, mode, UCI_FILEMODE);
 632         if (fd <= 0)
 633                 goto error;
 634
 635         if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)
 636                 goto error;
 637
 638         ret = lseek(fd, 0, pos);
 639
 640         if (ret < 0)
 641                 goto error;
 642
 643         file = fdopen(fd, (write ? "w+" : "r"));
 644         if (file)
 645                 goto done;
 646
 647 error:
 648         UCI_THROW(ctx, UCI_ERR_IO);
 649 done:
 650         return file;
 651 }
 652
 653 static void uci_close_stream(FILE *stream)
 654 {
 655         int fd;
 656
 657         if (!stream)
 658                 return;
 659
 660         fd = fileno(stream);
 661         flock(fd, LOCK_UN);
 662         fclose(stream);
 663 }
 664
 665 static void uci_parse_history_line(struct uci_context *ctx, struct uci_package *p, char *buf)
 666 {
 667         bool delete = false;
 668         bool rename = false;
 669         char *package = NULL;
 670         char *section = NULL;
 671         char *option = NULL;
 672         char *value = NULL;
 673
 674         if (buf[0] == '-') {
 675                 delete = true;
 676                 buf++;
 677         } else if (buf[0] == '@') {
 678                 rename = true;
 679                 buf++;
 680         }
 681
 682         UCI_INTERNAL(uci_parse_tuple, ctx, buf, &package, &section, &option, &value);
 683         if (!package || !section || (!delete && !value))
 684                 goto error;
 685         if (strcmp(package, p->e.name) != 0)
 686                 goto error;
 687         if (!uci_validate_name(section))
 688                 goto error;
 689         if (option && !uci_validate_name(option))
 690                 goto error;
 691
 692         if (rename)
 693                 UCI_INTERNAL(uci_rename, ctx, p, section, option, value);
 694         else if (delete)
 695                 UCI_INTERNAL(uci_delete, ctx, p, section, option);
 696         else
 697                 UCI_INTERNAL(uci_set, ctx, p, section, option, value);
 698
 699         return;
 700 error:
 701         UCI_THROW(ctx, UCI_ERR_PARSE);
 702 }
 703
 704 static void uci_parse_history(struct uci_context *ctx, FILE *stream, struct uci_package *p)
 705 {
 706         struct uci_parse_context *pctx;
 707
 708         /* make sure no memory from previous parse attempts is leaked */
 709         uci_file_cleanup(ctx);
 710
 711         pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
 712         ctx->pctx = pctx;
 713         pctx->file = stream;
 714
 715         while (!feof(pctx->file)) {
 716                 uci_getln(ctx, 0);
 717                 if (!pctx->buf[0])
 718                         continue;
 719
 720                 /*
 721                  * ignore parse errors in single lines, we want to preserve as much
 722                  * history as possible
 723                  */
 724                 UCI_TRAP_SAVE(ctx, error);
 725                 uci_parse_history_line(ctx, p, pctx->buf);
 726                 UCI_TRAP_RESTORE(ctx);
 727 error:
 728                 continue;
 729         }
 730
 731         /* no error happened, we can get rid of the parser context now */
 732         uci_file_cleanup(ctx);
 733 }
 734
 735 static void uci_load_history(struct uci_context *ctx, struct uci_package *p, bool flush)
 736 {
 737         char *filename = NULL;
 738         FILE *f = NULL;
 739
 740         if (!p->confdir)
 741                 return;
 742         if ((asprintf(&filename, "%s/%s", UCI_SAVEDIR, p->e.name) < 0) || !filename)
 743                 UCI_THROW(ctx, UCI_ERR_MEM);
 744
 745         UCI_TRAP_SAVE(ctx, done);
 746         f = uci_open_stream(ctx, filename, SEEK_SET, flush, false);
 747         if (p)
 748                 uci_parse_history(ctx, f, p);
 749         UCI_TRAP_RESTORE(ctx);
 750
 751 done:
 752         if (flush && f) {
 753                 rewind(f);
 754                 ftruncate(fileno(f), 0);
 755         }
 756         if (filename)
 757                 free(filename);
 758         uci_close_stream(f);
 759         ctx->errno = 0;
 760 }
 761
 762
 763 static char *uci_config_path(struct uci_context *ctx, const char *name)
 764 {
 765         char *filename;
 766
 767         if (strchr(name, '/'))
 768                 UCI_THROW(ctx, UCI_ERR_INVAL);
 769         filename = uci_malloc(ctx, strlen(name) + sizeof(UCI_CONFDIR) + 2);
 770         sprintf(filename, UCI_CONFDIR "/%s", name);
 771
 772         return filename;
 773 }
 774
 775 int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
 776 {
 777         char *filename;
 778         bool confdir;
 779         FILE *file = NULL;
 780
 781         UCI_HANDLE_ERR(ctx);
 782         UCI_ASSERT(ctx, uci_validate_name(name));
 783
 784         switch (name[0]) {
 785         case '.':
 786                 /* relative path outside of /etc/config */
 787                 if (name[1] != '/')
 788                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 789                 /* fall through */
 790         case '/':
 791                 /* absolute path outside of /etc/config */
 792                 filename = uci_strdup(ctx, name);
 793                 name = strrchr(name, '/') + 1;
 794                 confdir = false;
 795                 break;
 796         default:
 797                 /* config in /etc/config */
 798                 filename = uci_config_path(ctx, name);
 799                 confdir = true;
 800                 break;
 801         }
 802
 803         file = uci_open_stream(ctx, filename, SEEK_SET, false, false);
 804         ctx->errno = 0;
 805         UCI_TRAP_SAVE(ctx, done);
 806         UCI_INTERNAL(uci_import, ctx, file, name, package, true);
 807         UCI_TRAP_RESTORE(ctx);
 808
 809         if (*package) {
 810                 (*package)->path = filename;
 811                 (*package)->confdir = confdir;
 812                 uci_load_history(ctx, *package, false);
 813         }
 814
 815 done:
 816         uci_close_stream(file);
 817         return ctx->errno;
 818 }
 819
 820 int uci_save(struct uci_context *ctx, struct uci_package *p)
 821 {
 822         FILE *f = NULL;
 823         char *filename = NULL;
 824         struct uci_element *e, *tmp;
 825
 826         UCI_HANDLE_ERR(ctx);
 827         UCI_ASSERT(ctx, p != NULL);
 828
 829         /*
 830          * if the config file was outside of the /etc/config path,
 831          * don't save the history to a file, update the real file
 832          * directly.
 833          * does not modify the uci_package pointer
 834          */
 835         if (!p->confdir)
 836                 return uci_commit(ctx, &p, false);
 837
 838         if (uci_list_empty(&p->history))
 839                 return 0;
 840
 841         if ((asprintf(&filename, "%s/%s", UCI_SAVEDIR, p->e.name) < 0) || !filename)
 842                 UCI_THROW(ctx, UCI_ERR_MEM);
 843
 844         ctx->errno = 0;
 845         UCI_TRAP_SAVE(ctx, done);
 846         f = uci_open_stream(ctx, filename, SEEK_END, true, true);
 847         UCI_TRAP_RESTORE(ctx);
 848
 849         uci_foreach_element_safe(&p->history, tmp, e) {
 850                 struct uci_history *h = uci_to_history(e);
 851
 852                 if (h->cmd == UCI_CMD_REMOVE)
 853                         fprintf(f, "-");
 854                 else if (h->cmd == UCI_CMD_RENAME)
 855                         fprintf(f, "@");
 856
 857                 fprintf(f, "%s.%s", p->e.name, h->section);
 858                 if (e->name)
 859                         fprintf(f, ".%s", e->name);
 860
 861                 if (h->cmd == UCI_CMD_REMOVE)
 862                         fprintf(f, "\n");
 863                 else
 864                         fprintf(f, "=%s\n", h->value);
 865                 uci_free_history(h);
 866         }
 867
 868 done:
 869         uci_close_stream(f);
 870         if (filename)
 871                 free(filename);
 872         if (ctx->errno)
 873                 UCI_THROW(ctx, ctx->errno);
 874
 875         return 0;
 876 }
 877
 878 int uci_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 879 {
 880         struct uci_package *p;
 881         FILE *f = NULL;
 882         char *name = NULL;
 883         char *path = NULL;
 884
 885         UCI_HANDLE_ERR(ctx);
 886         UCI_ASSERT(ctx, package != NULL);
 887         p = *package;
 888
 889         UCI_ASSERT(ctx, p != NULL);
 890         if (!p->path) {
 891                 if (overwrite)
 892                         p->path = uci_config_path(ctx, p->e.name);
 893                 else
 894                         UCI_THROW(ctx, UCI_ERR_INVAL);
 895         }
 896
 897
 898         /* open the config file for writing now, so that it is locked */
 899         f = uci_open_stream(ctx, p->path, SEEK_SET, true, true);
 900
 901         /* flush unsaved changes and reload from history file */
 902         UCI_TRAP_SAVE(ctx, done);
 903         if (p->confdir) {
 904                 if (!overwrite) {
 905                         name = uci_strdup(ctx, p->e.name);
 906                         path = uci_strdup(ctx, p->path);
 907                         if (!uci_list_empty(&p->history))
 908                                 UCI_INTERNAL(uci_save, ctx, p);
 909                         uci_free_package(&p);
 910                         uci_file_cleanup(ctx);
 911                         UCI_INTERNAL(uci_import, ctx, f, name, &p, true);
 912
 913                         p->path = path;
 914                         p->confdir = true;
 915                         *package = p;
 916
 917                         /* freed together with the uci_package */
 918                         path = NULL;
 919
 920                         /* check for updated history, just in case */
 921                         uci_load_history(ctx, p, true);
 922                 } else {
 923                         /* flush history */
 924                         uci_load_history(ctx, NULL, true);
 925                 }
 926         }
 927
 928         rewind(f);
 929         ftruncate(fileno(f), 0);
 930
 931         uci_export(ctx, f, p, false);
 932         UCI_TRAP_RESTORE(ctx);
 933
 934 done:
 935         if (name)
 936                 free(name);
 937         if (path)
 938                 free(path);
 939         uci_close_stream(f);
 940         if (ctx->errno)
 941                 UCI_THROW(ctx, ctx->errno);
 942
 943         return 0;
 944 }
 945
 946
 947 /*
 948  * This function returns the filename by returning the string
 949  * after the last '/' character. By checking for a non-'\0'
 950  * character afterwards, directories are ignored (glob marks
 951  * those with a trailing '/'
 952  */
 953 static inline char *get_filename(char *path)
 954 {
 955         char *p;
 956
 957         p = strrchr(path, '/');
 958         p++;
 959         if (!*p)
 960                 return NULL;
 961         return p;
 962 }
 963
 964 int uci_list_configs(struct uci_context *ctx, char ***list)
 965 {
 966         char **configs;
 967         glob_t globbuf;
 968         int size, i;
 969         char *buf;
 970
 971         UCI_HANDLE_ERR(ctx);
 972
 973         if (glob(UCI_CONFDIR "/*", GLOB_MARK, NULL, &globbuf) != 0)
 974                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 975
 976         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 977         for(i = 0; i < globbuf.gl_pathc; i++) {
 978                 char *p;
 979
 980                 p = get_filename(globbuf.gl_pathv[i]);
 981                 if (!p)
 982                         continue;
 983
 984                 size += strlen(p) + 1;
 985         }
 986
 987         configs = uci_malloc(ctx, size);
 988         buf = (char *) &configs[globbuf.gl_pathc + 1];
 989         for(i = 0; i < globbuf.gl_pathc; i++) {
 990                 char *p;
 991
 992                 p = get_filename(globbuf.gl_pathv[i]);
 993                 if (!p)
 994                         continue;
 995
 996                 configs[i] = buf;
 997                 strcpy(buf, p);
 998                 buf += strlen(buf) + 1;
 999         }
1000         *list = configs;
1001
1002         return 0;
1003 }
1004