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         /* `offset' may off by one */
  52         if (offset >= pctx->bufsz) {
  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         uci_parse_error(ctx, "unterminated \"");
 161 }
 162
 163 /*
 164  * parse a single quoted string argument from the command line
 165  */
 166 static void parse_single_quote(struct uci_context *ctx, int *target)
 167 {
 168         struct uci_parse_context *pctx = ctx->pctx;
 169         char c;
 170         /* skip quote character */
 171         pctx->pos += 1;
 172
 173         while (1) {
 174                 c = pctx_cur_char(pctx);
 175                 switch(c) {
 176                 case '\'':
 177                         pctx->pos += 1;
 178                         return;
 179                 case 0:
 180                         /* Multi-line str value */
 181                         uci_getln(ctx, pctx->pos);
 182                         if (!pctx_cur_char(pctx))
 183                                 uci_parse_error(ctx, "EOF with unterminated \"");
 184
 185                         break;
 186                 default:
 187                         addc(ctx, target, &pctx->pos);
 188                 }
 189         }
 190         uci_parse_error(ctx, "unterminated '");
 191 }
 192
 193 /*
 194  * parse a string from the command line and detect the quoting style
 195  */
 196 static void parse_str(struct uci_context *ctx, int *target)
 197 {
 198         struct uci_parse_context *pctx = ctx->pctx;
 199         bool next = true;
 200         do {
 201                 switch(pctx_cur_char(pctx)) {
 202                 case '\'':
 203                         parse_single_quote(ctx, target);
 204                         break;
 205                 case '"':
 206                         parse_double_quote(ctx, target);
 207                         break;
 208                 case '#':
 209                         pctx_cur_char(pctx) = 0;
 210                         /* fall through */
 211                 case 0:
 212                         goto done;
 213                 case ';':
 214                         next = false;
 215                         goto done;
 216                 case '\\':
 217                         if (!parse_backslash(ctx))
 218                                 continue;
 219                         /* fall through */
 220                 default:
 221                         addc(ctx, target, &pctx->pos);
 222                         break;
 223                 }
 224         } while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
 225 done:
 226
 227         /*
 228          * if the string was unquoted and we've stopped at a whitespace
 229          * character, skip to the next one, because the whitespace will
 230          * be overwritten by a null byte here
 231          */
 232         if (pctx_cur_char(pctx) && next)
 233                 pctx->pos += 1;
 234
 235         /* terminate the parsed string */
 236         pctx_char(pctx, *target) = 0;
 237 }
 238
 239 /*
 240  * extract the next argument from the command line
 241  */
 242 static int next_arg(struct uci_context *ctx, bool required, bool name)
 243 {
 244         struct uci_parse_context *pctx = ctx->pctx;
 245         int val, ptr;
 246
 247         skip_whitespace(ctx);
 248         val = ptr = pctx_pos(pctx);
 249         if (pctx_cur_char(pctx) == ';') {
 250                 pctx_cur_char(pctx) = 0;
 251                 pctx->pos += 1;
 252         } else {
 253                 parse_str(ctx, &ptr);
 254         }
 255         if (!pctx_char(pctx, val)) {
 256                 if (required)
 257                         uci_parse_error(ctx, "insufficient arguments");
 258                 goto done;
 259         }
 260
 261         if (name && !uci_validate_name(pctx_str(pctx, val)))
 262                 uci_parse_error(ctx, "invalid character in name field");
 263
 264 done:
 265         return val;
 266 }
 267
 268 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
 269 {
 270         int ofs_result;
 271
 272         UCI_HANDLE_ERR(ctx);
 273         UCI_ASSERT(ctx, str != NULL);
 274         UCI_ASSERT(ctx, result != NULL);
 275
 276         if (ctx->pctx && (ctx->pctx->file != stream))
 277                 uci_cleanup(ctx);
 278
 279         if (!ctx->pctx)
 280                 uci_alloc_parse_context(ctx);
 281
 282         ctx->pctx->file = stream;
 283
 284         if (!*str) {
 285                 uci_getln(ctx, 0);
 286                 *str = ctx->pctx->buf;
 287         } else {
 288                 UCI_ASSERT(ctx, ctx->pctx->pos == *str - ctx->pctx->buf);
 289         }
 290
 291         /*FIXME do we need to skip empty lines? */
 292         ofs_result = next_arg(ctx, false, false);
 293         *result = pctx_str(ctx->pctx, ofs_result);
 294         *str = pctx_cur_str(ctx->pctx);
 295
 296         return 0;
 297 }
 298
 299 static int
 300 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
 301 {
 302         UCI_ASSERT(ctx, ptr != NULL);
 303         UCI_ASSERT(ctx, e != NULL);
 304
 305         memset(ptr, 0, sizeof(struct uci_ptr));
 306         switch(e->type) {
 307         case UCI_TYPE_OPTION:
 308                 ptr->o = uci_to_option(e);
 309                 goto fill_option;
 310         case UCI_TYPE_SECTION:
 311                 ptr->s = uci_to_section(e);
 312                 goto fill_section;
 313         case UCI_TYPE_PACKAGE:
 314                 ptr->p = uci_to_package(e);
 315                 goto fill_package;
 316         default:
 317                 UCI_THROW(ctx, UCI_ERR_INVAL);
 318         }
 319
 320 fill_option:
 321         ptr->option = ptr->o->e.name;
 322         ptr->s = ptr->o->section;
 323 fill_section:
 324         ptr->section = ptr->s->e.name;
 325         ptr->p = ptr->s->package;
 326 fill_package:
 327         ptr->package = ptr->p->e.name;
 328
 329         ptr->flags |= UCI_LOOKUP_DONE;
 330
 331         return 0;
 332 }
 333
 334
 335
 336 /*
 337  * verify that the end of the line or command is reached.
 338  * throw an error if extra arguments are given on the command line
 339  */
 340 static void assert_eol(struct uci_context *ctx)
 341 {
 342         char *tmp;
 343         int ofs_tmp;
 344
 345         skip_whitespace(ctx);
 346         ofs_tmp = next_arg(ctx, false, false);
 347         tmp = pctx_str(ctx->pctx, ofs_tmp);
 348         if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
 349                 uci_parse_error(ctx, "too many arguments");
 350 }
 351
 352 /*
 353  * switch to a different config, either triggered by uci_load, or by a
 354  * 'package <...>' statement in the import file
 355  */
 356 static void uci_switch_config(struct uci_context *ctx)
 357 {
 358         struct uci_parse_context *pctx;
 359         struct uci_element *e;
 360         const char *name;
 361
 362         pctx = ctx->pctx;
 363         name = pctx->name;
 364
 365         /* add the last config to main config file list */
 366         if (pctx->package) {
 367                 pctx->package->backend = ctx->backend;
 368                 uci_list_add(&ctx->root, &pctx->package->e.list);
 369
 370                 pctx->package = NULL;
 371                 pctx->section = NULL;
 372         }
 373
 374         if (!name)
 375                 return;
 376
 377         /*
 378          * if an older config under the same name exists, unload it
 379          * ignore errors here, e.g. if the config was not found
 380          */
 381         e = uci_lookup_list(&ctx->root, name);
 382         if (e)
 383                 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 384         pctx->package = uci_alloc_package(ctx, name);
 385 }
 386
 387 /*
 388  * parse the 'package' uci command (next config package)
 389  */
 390 static void uci_parse_package(struct uci_context *ctx, bool single)
 391 {
 392         struct uci_parse_context *pctx = ctx->pctx;
 393         int ofs_name;
 394         char *name;
 395
 396         /* command string null-terminated by strtok */
 397         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 398
 399         ofs_name = next_arg(ctx, true, true);
 400         name = pctx_str(pctx, ofs_name);
 401         assert_eol(ctx);
 402         if (single)
 403                 return;
 404
 405         ctx->pctx->name = name;
 406         uci_switch_config(ctx);
 407 }
 408
 409 /*
 410  * parse the 'config' uci command (open a section)
 411  */
 412 static void uci_parse_config(struct uci_context *ctx)
 413 {
 414         struct uci_parse_context *pctx = ctx->pctx;
 415         struct uci_element *e;
 416         struct uci_ptr ptr;
 417         int ofs_name, ofs_type;
 418         char *name;
 419         char *type;
 420
 421         uci_fixup_section(ctx, ctx->pctx->section);
 422         if (!ctx->pctx->package) {
 423                 if (!ctx->pctx->name)
 424                         uci_parse_error(ctx, "attempting to import a file without a package name");
 425
 426                 uci_switch_config(ctx);
 427         }
 428
 429         /* command string null-terminated by strtok */
 430         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 431
 432         ofs_type = next_arg(ctx, true, false);
 433         type = pctx_str(pctx, ofs_type);
 434         if (!uci_validate_type(type))
 435                 uci_parse_error(ctx, "invalid character in type field");
 436
 437         ofs_name = next_arg(ctx, false, true);
 438         type = pctx_str(pctx, ofs_type);
 439         name = pctx_str(pctx, ofs_name);
 440         assert_eol(ctx);
 441
 442         if (!name || !name[0]) {
 443                 ctx->internal = !pctx->merge;
 444                 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
 445         } else {
 446                 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
 447                 e = uci_lookup_list(&pctx->package->sections, name);
 448                 if (e)
 449                         ptr.s = uci_to_section(e);
 450                 ptr.section = name;
 451                 ptr.value = type;
 452
 453                 ctx->internal = !pctx->merge;
 454                 UCI_NESTED(uci_set, ctx, &ptr);
 455                 pctx->section = uci_to_section(ptr.last);
 456         }
 457 }
 458
 459 /*
 460  * parse the 'option' uci command (open a value)
 461  */
 462 static void uci_parse_option(struct uci_context *ctx, bool list)
 463 {
 464         struct uci_parse_context *pctx = ctx->pctx;
 465         struct uci_element *e;
 466         struct uci_ptr ptr;
 467         int ofs_name, ofs_value;
 468         char *name = NULL;
 469         char *value = NULL;
 470
 471         if (!pctx->section)
 472                 uci_parse_error(ctx, "option/list command found before the first section");
 473
 474         /* command string null-terminated by strtok */
 475         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 476
 477         ofs_name = next_arg(ctx, true, true);
 478         ofs_value = next_arg(ctx, false, false);
 479         name = pctx_str(pctx, ofs_name);
 480         value = pctx_str(pctx, ofs_value);
 481         assert_eol(ctx);
 482
 483         uci_fill_ptr(ctx, &ptr, &pctx->section->e);
 484         e = uci_lookup_list(&pctx->section->options, name);
 485         if (e)
 486                 ptr.o = uci_to_option(e);
 487         ptr.option = name;
 488         ptr.value = value;
 489
 490         ctx->internal = !pctx->merge;
 491         if (list)
 492                 UCI_NESTED(uci_add_list, ctx, &ptr);
 493         else
 494                 UCI_NESTED(uci_set, ctx, &ptr);
 495 }
 496
 497 /*
 498  * parse a complete input line, split up combined commands by ';'
 499  */
 500 static void uci_parse_line(struct uci_context *ctx, bool single)
 501 {
 502         struct uci_parse_context *pctx = ctx->pctx;
 503         char *word;
 504
 505         /* Skip whitespace characters at the start of line */
 506         skip_whitespace(ctx);
 507         do {
 508                 word = strtok(pctx_cur_str(pctx), " \t");
 509                 if (!word)
 510                         return;
 511
 512                 switch(word[0]) {
 513                         case 0:
 514                         case '#':
 515                                 return;
 516                         case 'p':
 517                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 518                                         uci_parse_package(ctx, single);
 519                                 else
 520                                         goto invalid;
 521                                 break;
 522                         case 'c':
 523                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 524                                         uci_parse_config(ctx);
 525                                 else
 526                                         goto invalid;
 527                                 break;
 528                         case 'o':
 529                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 530                                         uci_parse_option(ctx, false);
 531                                 else
 532                                         goto invalid;
 533                                 break;
 534                         case 'l':
 535                                 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
 536                                         uci_parse_option(ctx, true);
 537                                 else
 538                                         goto invalid;
 539                                 break;
 540                         default:
 541                                 goto invalid;
 542                 }
 543                 continue;
 544 invalid:
 545                 uci_parse_error(ctx, "invalid command");
 546         } while (1);
 547 }
 548
 549 /* max number of characters that escaping adds to the string */
 550 #define UCI_QUOTE_ESCAPE        "'\\''"
 551
 552 /*
 553  * escape an uci string for export
 554  */
 555 static const char *uci_escape(struct uci_context *ctx, const char *str)
 556 {
 557         const char *end;
 558         int ofs = 0;
 559
 560         if (!ctx->buf) {
 561                 ctx->bufsz = LINEBUF;
 562                 ctx->buf = malloc(LINEBUF);
 563
 564                 if (!ctx->buf)
 565                         return str;
 566         }
 567
 568         while (1) {
 569                 int len;
 570
 571                 end = strchr(str, '\'');
 572                 if (!end)
 573                         end = str + strlen(str);
 574                 len = end - str;
 575
 576                 /* make sure that we have enough room in the buffer */
 577                 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
 578                         ctx->bufsz *= 2;
 579                         ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
 580                 }
 581
 582                 /* copy the string until the character before the quote */
 583                 memcpy(&ctx->buf[ofs], str, len);
 584                 ofs += len;
 585
 586                 /* end of string? return the buffer */
 587                 if (*end == 0)
 588                         break;
 589
 590                 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
 591                 ofs += strlen(&ctx->buf[ofs]);
 592                 str = end + 1;
 593         }
 594
 595         ctx->buf[ofs] = 0;
 596         return ctx->buf;
 597 }
 598
 599 /*
 600  * export a single config package to a file stream
 601  */
 602 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 603 {
 604         struct uci_context *ctx = p->ctx;
 605         struct uci_element *s, *o, *i;
 606
 607         if (header)
 608                 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
 609         uci_foreach_element(&p->sections, s) {
 610                 struct uci_section *sec = uci_to_section(s);
 611                 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
 612                 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
 613                         fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 614                 fprintf(stream, "\n");
 615                 uci_foreach_element(&sec->options, o) {
 616                         struct uci_option *opt = uci_to_option(o);
 617                         switch(opt->type) {
 618                         case UCI_TYPE_STRING:
 619                                 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
 620                                 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
 621                                 break;
 622                         case UCI_TYPE_LIST:
 623                                 uci_foreach_element(&opt->v.list, i) {
 624                                         fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
 625                                         fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
 626                                 }
 627                                 break;
 628                         default:
 629                                 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
 630                                 break;
 631                         }
 632                 }
 633         }
 634         fprintf(stream, "\n");
 635 }
 636
 637 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 638 {
 639         struct uci_element *e;
 640
 641         UCI_HANDLE_ERR(ctx);
 642         UCI_ASSERT(ctx, stream != NULL);
 643
 644         if (package)
 645                 uci_export_package(package, stream, header);
 646         else {
 647                 uci_foreach_element(&ctx->root, e) {
 648                         uci_export_package(uci_to_package(e), stream, header);
 649                 }
 650         }
 651
 652         return 0;
 653 }
 654
 655 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 656 {
 657         struct uci_parse_context *pctx;
 658         UCI_HANDLE_ERR(ctx);
 659
 660         /* make sure no memory from previous parse attempts is leaked */
 661         uci_cleanup(ctx);
 662
 663         uci_alloc_parse_context(ctx);
 664         pctx = ctx->pctx;
 665         pctx->file = stream;
 666         if (package && *package && single) {
 667                 pctx->package = *package;
 668                 pctx->merge = true;
 669         }
 670
 671         /*
 672          * If 'name' was supplied, assume that the supplied stream does not contain
 673          * the appropriate 'package <name>' string to specify the config name
 674          * NB: the config file can still override the package name
 675          */
 676         if (name) {
 677                 UCI_ASSERT(ctx, uci_validate_package(name));
 678                 pctx->name = name;
 679         }
 680
 681         while (!feof(pctx->file)) {
 682                 pctx->pos = 0;
 683                 uci_getln(ctx, 0);
 684                 UCI_TRAP_SAVE(ctx, error);
 685                 if (pctx->buf[0])
 686                         uci_parse_line(ctx, single);
 687                 UCI_TRAP_RESTORE(ctx);
 688                 continue;
 689 error:
 690                 if (ctx->flags & UCI_FLAG_PERROR)
 691                         uci_perror(ctx, NULL);
 692                 if ((ctx->err != UCI_ERR_PARSE) ||
 693                         (ctx->flags & UCI_FLAG_STRICT))
 694                         UCI_THROW(ctx, ctx->err);
 695         }
 696
 697         uci_fixup_section(ctx, ctx->pctx->section);
 698         if (!pctx->package && name)
 699                 uci_switch_config(ctx);
 700         if (package)
 701                 *package = pctx->package;
 702         if (pctx->merge)
 703                 pctx->package = NULL;
 704
 705         pctx->name = NULL;
 706         uci_switch_config(ctx);
 707
 708         /* no error happened, we can get rid of the parser context now */
 709         uci_cleanup(ctx);
 710
 711         return 0;
 712 }
 713
 714
 715 static char *uci_config_path(struct uci_context *ctx, const char *name)
 716 {
 717         char *filename;
 718
 719         UCI_ASSERT(ctx, uci_validate_package(name));
 720         filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
 721         sprintf(filename, "%s/%s", ctx->confdir, name);
 722
 723         return filename;
 724 }
 725
 726 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 727 {
 728         struct uci_package *p = *package;
 729         FILE *f1, *f2 = NULL;
 730         char *name = NULL;
 731         char *path = NULL;
 732         char *filename = NULL;
 733         struct stat statbuf;
 734         bool do_rename = false;
 735
 736         if (!p->path) {
 737                 if (overwrite)
 738                         p->path = uci_config_path(ctx, p->e.name);
 739                 else
 740                         UCI_THROW(ctx, UCI_ERR_INVAL);
 741         }
 742
 743         if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
 744                 UCI_THROW(ctx, UCI_ERR_MEM);
 745
 746         if (!mktemp(filename))
 747                 *filename = 0;
 748
 749         if (!*filename) {
 750                 free(filename);
 751                 UCI_THROW(ctx, UCI_ERR_IO);
 752         }
 753
 754         if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
 755                 UCI_THROW(ctx, UCI_ERR_IO);
 756
 757         /* open the config file for writing now, so that it is locked */
 758         f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
 759
 760         /* flush unsaved changes and reload from delta file */
 761         UCI_TRAP_SAVE(ctx, done);
 762         if (p->has_delta) {
 763                 if (!overwrite) {
 764                         name = uci_strdup(ctx, p->e.name);
 765                         path = uci_strdup(ctx, p->path);
 766                         /* dump our own changes to the delta file */
 767                         if (!uci_list_empty(&p->delta))
 768                                 UCI_INTERNAL(uci_save, ctx, p);
 769
 770                         /*
 771                          * other processes might have modified the config
 772                          * as well. dump and reload
 773                          */
 774                         uci_free_package(&p);
 775                         uci_cleanup(ctx);
 776                         UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
 777
 778                         p->path = path;
 779                         p->has_delta = true;
 780                         *package = p;
 781
 782                         /* freed together with the uci_package */
 783                         path = NULL;
 784                 }
 785
 786                 /* flush delta */
 787                 if (!uci_load_delta(ctx, p, true))
 788                         goto done;
 789         }
 790
 791         f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
 792         uci_export(ctx, f2, p, false);
 793
 794         fflush(f2);
 795         fsync(fileno(f2));
 796         uci_close_stream(f2);
 797
 798         do_rename = true;
 799
 800         UCI_TRAP_RESTORE(ctx);
 801
 802 done:
 803         free(name);
 804         free(path);
 805         uci_close_stream(f1);
 806         if (do_rename && rename(filename, p->path)) {
 807                 unlink(filename);
 808                 UCI_THROW(ctx, UCI_ERR_IO);
 809         }
 810         free(filename);
 811         sync();
 812         if (ctx->err)
 813                 UCI_THROW(ctx, ctx->err);
 814 }
 815
 816
 817 /*
 818  * This function returns the filename by returning the string
 819  * after the last '/' character. By checking for a non-'\0'
 820  * character afterwards, directories are ignored (glob marks
 821  * those with a trailing '/'
 822  */
 823 static inline char *get_filename(char *path)
 824 {
 825         char *p;
 826
 827         p = strrchr(path, '/');
 828         p++;
 829         if (!*p)
 830                 return NULL;
 831         return p;
 832 }
 833
 834 static char **uci_list_config_files(struct uci_context *ctx)
 835 {
 836         char **configs;
 837         glob_t globbuf;
 838         int size, i;
 839         char *buf;
 840         char *dir;
 841
 842         dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
 843         sprintf(dir, "%s/*", ctx->confdir);
 844         if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
 845                 free(dir);
 846                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 847         }
 848
 849         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 850         for(i = 0; i < globbuf.gl_pathc; i++) {
 851                 char *p;
 852
 853                 p = get_filename(globbuf.gl_pathv[i]);
 854                 if (!p)
 855                         continue;
 856
 857                 size += strlen(p) + 1;
 858         }
 859
 860         configs = uci_malloc(ctx, size);
 861         buf = (char *) &configs[globbuf.gl_pathc + 1];
 862         for(i = 0; i < globbuf.gl_pathc; i++) {
 863                 char *p;
 864
 865                 p = get_filename(globbuf.gl_pathv[i]);
 866                 if (!p)
 867                         continue;
 868
 869                 if (!uci_validate_package(p))
 870                         continue;
 871
 872                 configs[i] = buf;
 873                 strcpy(buf, p);
 874                 buf += strlen(buf) + 1;
 875         }
 876         free(dir);
 877         globfree(&globbuf);
 878         return configs;
 879 }
 880
 881 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
 882 {
 883         struct uci_package *package = NULL;
 884         char *filename;
 885         bool confdir;
 886         FILE *file = NULL;
 887
 888         switch (name[0]) {
 889         case '.':
 890                 /* relative path outside of /etc/config */
 891                 if (name[1] != '/')
 892                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 893                 /* fall through */
 894         case '/':
 895                 /* absolute path outside of /etc/config */
 896                 filename = uci_strdup(ctx, name);
 897                 name = strrchr(name, '/') + 1;
 898                 confdir = false;
 899                 break;
 900         default:
 901                 /* config in /etc/config */
 902                 filename = uci_config_path(ctx, name);
 903                 confdir = true;
 904                 break;
 905         }
 906
 907         UCI_TRAP_SAVE(ctx, done);
 908         file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
 909         ctx->err = 0;
 910         UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
 911         UCI_TRAP_RESTORE(ctx);
 912
 913         if (package) {
 914                 package->path = filename;
 915                 package->has_delta = confdir;
 916                 uci_load_delta(ctx, package, false);
 917         }
 918
 919 done:
 920         uci_close_stream(file);
 921         if (ctx->err) {
 922                 free(filename);
 923                 UCI_THROW(ctx, ctx->err);
 924         }
 925         return package;
 926 }
 927
 928 __private UCI_BACKEND(uci_file_backend, "file",
 929         .load = uci_file_load,
 930         .commit = uci_file_commit,
 931         .list_configs = uci_list_config_files,
 932 );