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