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                 if (!pctx->buf)
  74                         UCI_THROW(ctx, UCI_ERR_MEM);
  75         } while (1);
  76 }
  77
  78 /*
  79  * parse a character escaped by '\'
  80  * returns true if the escaped character is to be parsed
  81  * returns false if the escaped character is to be ignored
  82  */
  83 static bool parse_backslash(struct uci_context *ctx)
  84 {
  85         struct uci_parse_context *pctx = ctx->pctx;
  86
  87         /* skip backslash */
  88         pctx->pos += 1;
  89
  90         /* undecoded backslash at the end of line, fetch the next line */
  91         if (!pctx_cur_char(pctx) ||
  92             pctx_cur_char(pctx) == '\n' ||
  93             (pctx_cur_char(pctx) == '\r' &&
  94              pctx_char(pctx, pctx_pos(pctx) + 1) == '\n' &&
  95              !pctx_char(pctx, pctx_pos(pctx) + 2))) {
  96                 uci_getln(ctx, pctx->pos);
  97                 return false;
  98         }
  99
 100         /* FIXME: decode escaped char, necessary? */
 101         return true;
 102 }
 103
 104 /*
 105  * move the string pointer forward until a non-whitespace character or
 106  * EOL is reached
 107  */
 108 static void skip_whitespace(struct uci_context *ctx)
 109 {
 110         struct uci_parse_context *pctx = ctx->pctx;
 111
 112         while (pctx_cur_char(pctx) && isspace(pctx_cur_char(pctx)))
 113                 pctx->pos += 1;
 114 }
 115
 116 static inline void addc(struct uci_context *ctx, int *pos_dest, int *pos_src)
 117 {
 118         struct uci_parse_context *pctx = ctx->pctx;
 119
 120         pctx_char(pctx, *pos_dest) = pctx_char(pctx, *pos_src);
 121         *pos_dest += 1;
 122         *pos_src += 1;
 123 }
 124
 125 /*
 126  * parse a double quoted string argument from the command line
 127  */
 128 static void parse_double_quote(struct uci_context *ctx, int *target)
 129 {
 130         struct uci_parse_context *pctx = ctx->pctx;
 131         char c;
 132
 133         /* skip quote character */
 134         pctx->pos += 1;
 135
 136         while (1) {
 137                 c = pctx_cur_char(pctx);
 138                 switch(c) {
 139                 case '"':
 140                         pctx->pos += 1;
 141                         return;
 142                 case 0:
 143                         /* Multi-line str value */
 144                         uci_getln(ctx, pctx->pos);
 145                         if (!pctx_cur_char(pctx)) {
 146                                 uci_parse_error(ctx, "EOF with unterminated \"");
 147                         }
 148                         break;
 149                 case '\\':
 150                         if (!parse_backslash(ctx))
 151                                 continue;
 152                         /* fall through */
 153                 default:
 154                         addc(ctx, target, &pctx->pos);
 155                         break;
 156                 }
 157         }
 158 }
 159
 160 /*
 161  * parse a single quoted string argument from the command line
 162  */
 163 static void parse_single_quote(struct uci_context *ctx, int *target)
 164 {
 165         struct uci_parse_context *pctx = ctx->pctx;
 166         char c;
 167         /* skip quote character */
 168         pctx->pos += 1;
 169
 170         while (1) {
 171                 c = pctx_cur_char(pctx);
 172                 switch(c) {
 173                 case '\'':
 174                         pctx->pos += 1;
 175                         return;
 176                 case 0:
 177                         /* Multi-line str value */
 178                         uci_getln(ctx, pctx->pos);
 179                         if (!pctx_cur_char(pctx))
 180                                 uci_parse_error(ctx, "EOF with unterminated '");
 181
 182                         break;
 183                 default:
 184                         addc(ctx, target, &pctx->pos);
 185                 }
 186         }
 187 }
 188
 189 /*
 190  * parse a string from the command line and detect the quoting style
 191  */
 192 static void parse_str(struct uci_context *ctx, int *target)
 193 {
 194         struct uci_parse_context *pctx = ctx->pctx;
 195         bool next = true;
 196         do {
 197                 switch(pctx_cur_char(pctx)) {
 198                 case '\'':
 199                         parse_single_quote(ctx, target);
 200                         break;
 201                 case '"':
 202                         parse_double_quote(ctx, target);
 203                         break;
 204                 case '#':
 205                         pctx_cur_char(pctx) = 0;
 206                         /* fall through */
 207                 case 0:
 208                         goto done;
 209                 case ';':
 210                         next = false;
 211                         goto done;
 212                 case '\\':
 213                         if (!parse_backslash(ctx))
 214                                 continue;
 215                         /* fall through */
 216                 default:
 217                         addc(ctx, target, &pctx->pos);
 218                         break;
 219                 }
 220         } while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
 221 done:
 222
 223         /*
 224          * if the string was unquoted and we've stopped at a whitespace
 225          * character, skip to the next one, because the whitespace will
 226          * be overwritten by a null byte here
 227          */
 228         if (pctx_cur_char(pctx) && next)
 229                 pctx->pos += 1;
 230
 231         /* terminate the parsed string */
 232         pctx_char(pctx, *target) = 0;
 233 }
 234
 235 /*
 236  * extract the next argument from the command line
 237  */
 238 static int next_arg(struct uci_context *ctx, bool required, bool name, bool package)
 239 {
 240         struct uci_parse_context *pctx = ctx->pctx;
 241         int val, ptr;
 242
 243         skip_whitespace(ctx);
 244         val = ptr = pctx_pos(pctx);
 245         if (pctx_cur_char(pctx) == ';') {
 246                 pctx_cur_char(pctx) = 0;
 247                 pctx->pos += 1;
 248         } else {
 249                 parse_str(ctx, &ptr);
 250         }
 251         if (!pctx_char(pctx, val)) {
 252                 if (required)
 253                         uci_parse_error(ctx, "insufficient arguments");
 254                 goto done;
 255         }
 256
 257         if (name && !uci_validate_str(pctx_str(pctx, val), name, package))
 258                 uci_parse_error(ctx, "invalid character in name field");
 259
 260 done:
 261         return val;
 262 }
 263
 264 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
 265 {
 266         int ofs_result;
 267
 268         UCI_HANDLE_ERR(ctx);
 269         UCI_ASSERT(ctx, str != NULL);
 270         UCI_ASSERT(ctx, result != NULL);
 271
 272         if (ctx->pctx && (ctx->pctx->file != stream))
 273                 uci_cleanup(ctx);
 274
 275         if (!ctx->pctx)
 276                 uci_alloc_parse_context(ctx);
 277
 278         ctx->pctx->file = stream;
 279         if (!*str) {
 280                 ctx->pctx->pos = 0;
 281                 uci_getln(ctx, 0);
 282         }
 283
 284         ofs_result = next_arg(ctx, false, false, false);
 285         *result = pctx_str(ctx->pctx, ofs_result);
 286         *str = pctx_cur_str(ctx->pctx);
 287
 288         return 0;
 289 }
 290
 291 /*
 292  * Fixup sections functions does the fixup of all sections for given package.
 293  * It is used as a preprocessing step for fixing up existing anonymous sections
 294  * from configurations.
 295  *
 296  * It uses uci_fixup_section() from list.c and then adds delta changes.
 297  */
 298 static void
 299 uci_fixup_sections(struct uci_context *ctx, struct uci_package *p)
 300 {
 301         struct uci_element *e;
 302         struct uci_section *s;
 303
 304         uci_foreach_element(&p->sections, e) {
 305                 s = uci_to_section(e);
 306                 s->package->name_index++;
 307                 uci_fixup_section(ctx, s);
 308                 s->anonymous = false;
 309         }
 310 }
 311
 312 static int
 313 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
 314 {
 315         UCI_ASSERT(ctx, ptr != NULL);
 316         UCI_ASSERT(ctx, e != NULL);
 317
 318         memset(ptr, 0, sizeof(struct uci_ptr));
 319         switch(e->type) {
 320         case UCI_TYPE_OPTION:
 321                 ptr->o = uci_to_option(e);
 322                 goto fill_option;
 323         case UCI_TYPE_SECTION:
 324                 ptr->s = uci_to_section(e);
 325                 goto fill_section;
 326         case UCI_TYPE_PACKAGE:
 327                 ptr->p = uci_to_package(e);
 328                 goto fill_package;
 329         default:
 330                 UCI_THROW(ctx, UCI_ERR_INVAL);
 331         }
 332
 333 fill_option:
 334         ptr->option = ptr->o->e.name;
 335         ptr->s = ptr->o->section;
 336 fill_section:
 337         ptr->section = ptr->s->e.name;
 338         ptr->p = ptr->s->package;
 339 fill_package:
 340         ptr->package = ptr->p->e.name;
 341
 342         ptr->flags |= UCI_LOOKUP_DONE;
 343
 344         return 0;
 345 }
 346
 347
 348
 349 /*
 350  * verify that the end of the line or command is reached.
 351  * throw an error if extra arguments are given on the command line
 352  */
 353 static void assert_eol(struct uci_context *ctx)
 354 {
 355         char *tmp;
 356         int ofs_tmp;
 357
 358         skip_whitespace(ctx);
 359         ofs_tmp = next_arg(ctx, false, false, false);
 360         tmp = pctx_str(ctx->pctx, ofs_tmp);
 361         if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
 362                 uci_parse_error(ctx, "too many arguments");
 363 }
 364
 365 /*
 366  * switch to a different config, either triggered by uci_load, or by a
 367  * 'package <...>' statement in the import file
 368  */
 369 static void uci_switch_config(struct uci_context *ctx)
 370 {
 371         struct uci_parse_context *pctx;
 372         struct uci_element *e;
 373         const char *name;
 374
 375         pctx = ctx->pctx;
 376         name = pctx->name;
 377
 378         /* add the last config to main config file list */
 379         if (pctx->package) {
 380                 pctx->package->backend = ctx->backend;
 381                 uci_list_add(&ctx->root, &pctx->package->e.list);
 382
 383                 pctx->package = NULL;
 384                 pctx->section = NULL;
 385         }
 386
 387         if (!name)
 388                 return;
 389
 390         /*
 391          * if an older config under the same name exists, unload it
 392          * ignore errors here, e.g. if the config was not found
 393          */
 394         e = uci_lookup_list(&ctx->root, name);
 395         if (e)
 396                 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 397         pctx->package = uci_alloc_package(ctx, name);
 398 }
 399
 400 /*
 401  * parse the 'package' uci command (next config package)
 402  */
 403 static void uci_parse_package(struct uci_context *ctx, bool single)
 404 {
 405         struct uci_parse_context *pctx = ctx->pctx;
 406         int ofs_name;
 407         char *name;
 408
 409         /* command string null-terminated by strtok */
 410         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 411
 412         ofs_name = next_arg(ctx, true, true, true);
 413         name = pctx_str(pctx, ofs_name);
 414         assert_eol(ctx);
 415         if (single)
 416                 return;
 417
 418         ctx->pctx->name = name;
 419         uci_switch_config(ctx);
 420 }
 421
 422 /*
 423  * parse the 'config' uci command (open a section)
 424  */
 425 static void uci_parse_config(struct uci_context *ctx)
 426 {
 427         struct uci_parse_context *pctx = ctx->pctx;
 428         struct uci_element *e;
 429         struct uci_ptr ptr;
 430         int ofs_name, ofs_type;
 431         char *name;
 432         char *type;
 433
 434         if (!ctx->pctx->package) {
 435                 if (!ctx->pctx->name)
 436                         uci_parse_error(ctx, "attempting to import a file without a package name");
 437
 438                 uci_switch_config(ctx);
 439         }
 440
 441         /* command string null-terminated by strtok */
 442         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 443
 444         ofs_type = next_arg(ctx, true, false, false);
 445         type = pctx_str(pctx, ofs_type);
 446         if (!uci_validate_type(type))
 447                 uci_parse_error(ctx, "invalid character in type field");
 448
 449         ofs_name = next_arg(ctx, false, true, false);
 450         type = pctx_str(pctx, ofs_type);
 451         name = pctx_str(pctx, ofs_name);
 452         assert_eol(ctx);
 453
 454         if (!name || !name[0]) {
 455                 ctx->internal = !pctx->merge;
 456                 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
 457         } else {
 458                 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
 459                 e = uci_lookup_list(&pctx->package->sections, name);
 460                 if (e) {
 461                         ptr.s = uci_to_section(e);
 462
 463                         if ((ctx->flags & UCI_FLAG_STRICT) && strcmp(ptr.s->type, type))
 464                                 uci_parse_error(ctx, "section of different type overwrites prior section with same name");
 465                 }
 466
 467                 ptr.section = name;
 468                 ptr.value = type;
 469
 470                 ctx->internal = !pctx->merge;
 471                 UCI_NESTED(uci_set, ctx, &ptr);
 472                 pctx->section = uci_to_section(ptr.last);
 473         }
 474 }
 475
 476 /*
 477  * parse the 'option' uci command (open a value)
 478  */
 479 static void uci_parse_option(struct uci_context *ctx, bool list)
 480 {
 481         struct uci_parse_context *pctx = ctx->pctx;
 482         struct uci_element *e;
 483         struct uci_ptr ptr;
 484         int ofs_name, ofs_value;
 485         char *name = NULL;
 486         char *value = NULL;
 487
 488         if (!pctx->section)
 489                 uci_parse_error(ctx, "option/list command found before the first section");
 490
 491         /* command string null-terminated by strtok */
 492         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 493
 494         ofs_name = next_arg(ctx, true, true, false);
 495         ofs_value = next_arg(ctx, false, false, false);
 496         name = pctx_str(pctx, ofs_name);
 497         value = pctx_str(pctx, ofs_value);
 498         assert_eol(ctx);
 499
 500         uci_fill_ptr(ctx, &ptr, &pctx->section->e);
 501         e = uci_lookup_list(&pctx->section->options, name);
 502         if (e)
 503                 ptr.o = uci_to_option(e);
 504         ptr.option = name;
 505         ptr.value = value;
 506
 507         ctx->internal = !pctx->merge;
 508         if (list)
 509                 UCI_NESTED(uci_add_list, ctx, &ptr);
 510         else
 511                 UCI_NESTED(uci_set, ctx, &ptr);
 512 }
 513
 514 /*
 515  * parse a complete input line, split up combined commands by ';'
 516  */
 517 static void uci_parse_line(struct uci_context *ctx, bool single)
 518 {
 519         struct uci_parse_context *pctx = ctx->pctx;
 520         char *word;
 521
 522         /* Skip whitespace characters at the start of line */
 523         skip_whitespace(ctx);
 524         do {
 525                 word = strtok(pctx_cur_str(pctx), " \t");
 526                 if (!word)
 527                         return;
 528
 529                 switch(word[0]) {
 530                         case 0:
 531                         case '#':
 532                                 return;
 533                         case 'p':
 534                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 535                                         uci_parse_package(ctx, single);
 536                                 else
 537                                         goto invalid;
 538                                 break;
 539                         case 'c':
 540                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 541                                         uci_parse_config(ctx);
 542                                 else
 543                                         goto invalid;
 544                                 break;
 545                         case 'o':
 546                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 547                                         uci_parse_option(ctx, false);
 548                                 else
 549                                         goto invalid;
 550                                 break;
 551                         case 'l':
 552                                 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
 553                                         uci_parse_option(ctx, true);
 554                                 else
 555                                         goto invalid;
 556                                 break;
 557                         default:
 558                                 goto invalid;
 559                 }
 560                 continue;
 561 invalid:
 562                 uci_parse_error(ctx, "invalid command");
 563         } while (1);
 564 }
 565
 566 /* max number of characters that escaping adds to the string */
 567 #define UCI_QUOTE_ESCAPE        "'\\''"
 568
 569 /*
 570  * escape an uci string for export
 571  */
 572 static const char *uci_escape(struct uci_context *ctx, const char *str)
 573 {
 574         const char *end;
 575         int ofs = 0;
 576
 577         if (!ctx->buf) {
 578                 ctx->bufsz = LINEBUF;
 579                 ctx->buf = malloc(LINEBUF);
 580
 581                 if (!ctx->buf)
 582                         return str;
 583         }
 584
 585         while (1) {
 586                 int len;
 587
 588                 end = strchr(str, '\'');
 589                 if (!end)
 590                         end = str + strlen(str);
 591                 len = end - str;
 592
 593                 /* make sure that we have enough room in the buffer */
 594                 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
 595                         ctx->bufsz *= 2;
 596                         ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
 597                 }
 598
 599                 /* copy the string until the character before the quote */
 600                 memcpy(&ctx->buf[ofs], str, len);
 601                 ofs += len;
 602
 603                 /* end of string? return the buffer */
 604                 if (*end == 0)
 605                         break;
 606
 607                 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
 608                 ofs += strlen(&ctx->buf[ofs]);
 609                 str = end + 1;
 610         }
 611
 612         ctx->buf[ofs] = 0;
 613         return ctx->buf;
 614 }
 615
 616 /*
 617  * export a single config package to a file stream
 618  */
 619 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 620 {
 621         struct uci_context *ctx = p->ctx;
 622         struct uci_element *s, *o, *i;
 623
 624         if (header)
 625                 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
 626         uci_foreach_element(&p->sections, s) {
 627                 struct uci_section *sec = uci_to_section(s);
 628                 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
 629                 fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 630                 fprintf(stream, "\n");
 631                 uci_foreach_element(&sec->options, o) {
 632                         struct uci_option *opt = uci_to_option(o);
 633                         switch(opt->type) {
 634                         case UCI_TYPE_STRING:
 635                                 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
 636                                 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
 637                                 break;
 638                         case UCI_TYPE_LIST:
 639                                 uci_foreach_element(&opt->v.list, i) {
 640                                         fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
 641                                         fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
 642                                 }
 643                                 break;
 644                         default:
 645                                 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
 646                                 break;
 647                         }
 648                 }
 649         }
 650         fprintf(stream, "\n");
 651 }
 652
 653 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 654 {
 655         struct uci_element *e;
 656
 657         UCI_HANDLE_ERR(ctx);
 658         UCI_ASSERT(ctx, stream != NULL);
 659
 660         if (package)
 661                 uci_export_package(package, stream, header);
 662         else {
 663                 uci_foreach_element(&ctx->root, e) {
 664                         uci_export_package(uci_to_package(e), stream, header);
 665                 }
 666         }
 667
 668         return 0;
 669 }
 670
 671 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 672 {
 673         struct uci_parse_context *pctx;
 674         UCI_HANDLE_ERR(ctx);
 675
 676         /* make sure no memory from previous parse attempts is leaked */
 677         uci_cleanup(ctx);
 678
 679         uci_alloc_parse_context(ctx);
 680         pctx = ctx->pctx;
 681         pctx->file = stream;
 682         if (package && *package && single) {
 683                 pctx->package = *package;
 684                 pctx->merge = true;
 685         }
 686
 687         /*
 688          * If 'name' was supplied, assume that the supplied stream does not contain
 689          * the appropriate 'package <name>' string to specify the config name
 690          * NB: the config file can still override the package name
 691          */
 692         if (name) {
 693                 UCI_ASSERT(ctx, uci_validate_package(name));
 694                 pctx->name = name;
 695         }
 696
 697         while (!feof(pctx->file)) {
 698                 pctx->pos = 0;
 699                 uci_getln(ctx, 0);
 700                 UCI_TRAP_SAVE(ctx, error);
 701                 if (pctx->buf[0])
 702                         uci_parse_line(ctx, single);
 703                 UCI_TRAP_RESTORE(ctx);
 704                 continue;
 705 error:
 706                 if (ctx->flags & UCI_FLAG_PERROR)
 707                         uci_perror(ctx, NULL);
 708                 if ((ctx->err != UCI_ERR_PARSE) ||
 709                         (ctx->flags & UCI_FLAG_STRICT))
 710                         UCI_THROW(ctx, ctx->err);
 711         }
 712
 713         if (!pctx->package && name)
 714                 uci_switch_config(ctx);
 715         if (package)
 716                 *package = pctx->package;
 717         if (pctx->merge)
 718                 pctx->package = NULL;
 719
 720         uci_fixup_sections(ctx, *package);
 721         pctx->name = NULL;
 722         uci_switch_config(ctx);
 723
 724         /* no error happened, we can get rid of the parser context now */
 725         uci_cleanup(ctx);
 726
 727         return 0;
 728 }
 729
 730
 731 static char *uci_config_path(struct uci_context *ctx, const char *name)
 732 {
 733         char *filename;
 734
 735         UCI_ASSERT(ctx, uci_validate_package(name));
 736         filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
 737         sprintf(filename, "%s/%s", ctx->confdir, name);
 738
 739         return filename;
 740 }
 741
 742 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 743 {
 744         struct uci_package *p = *package;
 745         FILE *f1, *f2 = NULL;
 746         char *name = NULL;
 747         char *path = NULL;
 748         char *filename = NULL;
 749         struct stat statbuf;
 750         bool do_rename = false;
 751
 752         if (!p->path) {
 753                 if (overwrite)
 754                         p->path = uci_config_path(ctx, p->e.name);
 755                 else
 756                         UCI_THROW(ctx, UCI_ERR_INVAL);
 757         }
 758
 759         if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
 760                 UCI_THROW(ctx, UCI_ERR_MEM);
 761
 762         /* open the config file for writing now, so that it is locked */
 763         f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
 764
 765         /* flush unsaved changes and reload from delta file */
 766         UCI_TRAP_SAVE(ctx, done);
 767         if (p->has_delta) {
 768                 if (!overwrite) {
 769                         name = uci_strdup(ctx, p->e.name);
 770                         path = uci_strdup(ctx, p->path);
 771                         /* dump our own changes to the delta file */
 772                         if (!uci_list_empty(&p->delta))
 773                                 UCI_INTERNAL(uci_save, ctx, p);
 774
 775                         /*
 776                          * other processes might have modified the config
 777                          * as well. dump and reload
 778                          */
 779                         uci_free_package(&p);
 780                         uci_cleanup(ctx);
 781                         UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
 782
 783                         p->path = path;
 784                         p->has_delta = true;
 785                         *package = p;
 786
 787                         /* freed together with the uci_package */
 788                         path = NULL;
 789                 }
 790
 791                 /* flush delta */
 792                 if (!uci_load_delta(ctx, p, true))
 793                         goto done;
 794         }
 795
 796         if (!mktemp(filename))
 797                 *filename = 0;
 798
 799         if (!*filename) {
 800                 free(filename);
 801                 UCI_THROW(ctx, UCI_ERR_IO);
 802         }
 803
 804         if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
 805                 UCI_THROW(ctx, UCI_ERR_IO);
 806
 807         f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
 808         uci_export(ctx, f2, p, false);
 809
 810         fflush(f2);
 811         fsync(fileno(f2));
 812         uci_close_stream(f2);
 813
 814         do_rename = true;
 815
 816         UCI_TRAP_RESTORE(ctx);
 817
 818 done:
 819         free(name);
 820         free(path);
 821         uci_close_stream(f1);
 822         if (do_rename) {
 823                 path = realpath(p->path, NULL);
 824                 if (!path || rename(filename, path)) {
 825                         unlink(filename);
 826                         UCI_THROW(ctx, UCI_ERR_IO);
 827                 }
 828                 free(path);
 829         }
 830         free(filename);
 831         if (ctx->err)
 832                 UCI_THROW(ctx, ctx->err);
 833 }
 834
 835
 836 /*
 837  * This function returns the filename by returning the string
 838  * after the last '/' character. By checking for a non-'\0'
 839  * character afterwards, directories are ignored (glob marks
 840  * those with a trailing '/'
 841  */
 842 static inline char *get_filename(char *path)
 843 {
 844         char *p;
 845
 846         p = strrchr(path, '/');
 847         p++;
 848         if (!*p)
 849                 return NULL;
 850         return p;
 851 }
 852
 853 static char **uci_list_config_files(struct uci_context *ctx)
 854 {
 855         char **configs;
 856         glob_t globbuf;
 857         int size, i;
 858         char *buf;
 859         char *dir;
 860
 861         dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
 862         sprintf(dir, "%s/*", ctx->confdir);
 863         if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
 864                 free(dir);
 865                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 866         }
 867
 868         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 869         for(i = 0; i < globbuf.gl_pathc; i++) {
 870                 char *p;
 871
 872                 p = get_filename(globbuf.gl_pathv[i]);
 873                 if (!p)
 874                         continue;
 875
 876                 size += strlen(p) + 1;
 877         }
 878
 879         configs = uci_malloc(ctx, size);
 880         buf = (char *) &configs[globbuf.gl_pathc + 1];
 881         for(i = 0; i < globbuf.gl_pathc; i++) {
 882                 char *p;
 883
 884                 p = get_filename(globbuf.gl_pathv[i]);
 885                 if (!p)
 886                         continue;
 887
 888                 if (!uci_validate_package(p))
 889                         continue;
 890
 891                 configs[i] = buf;
 892                 strcpy(buf, p);
 893                 buf += strlen(buf) + 1;
 894         }
 895         free(dir);
 896         globfree(&globbuf);
 897         return configs;
 898 }
 899
 900 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
 901 {
 902         struct uci_package *package = NULL;
 903         char *filename;
 904         bool confdir;
 905         FILE *file = NULL;
 906         size_t n_change;
 907
 908         switch (name[0]) {
 909         case '.':
 910                 /* relative path outside of /etc/config */
 911                 if (name[1] != '/')
 912                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 913                 /* fall through */
 914         case '/':
 915                 /* absolute path outside of /etc/config */
 916                 filename = uci_strdup(ctx, name);
 917                 name = strrchr(name, '/') + 1;
 918                 confdir = false;
 919                 break;
 920         default:
 921                 /* config in /etc/config */
 922                 filename = uci_config_path(ctx, name);
 923                 confdir = true;
 924                 break;
 925         }
 926
 927         UCI_TRAP_SAVE(ctx, done);
 928         file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
 929         ctx->err = 0;
 930         UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
 931         UCI_TRAP_RESTORE(ctx);
 932
 933         if (package) {
 934                 package->path = filename;
 935                 package->has_delta = confdir;
 936                 n_change = uci_load_delta(ctx, package, false);
 937                 package->name_index += n_change;
 938         }
 939
 940 done:
 941         uci_close_stream(file);
 942         if (ctx->err) {
 943                 free(filename);
 944                 UCI_THROW(ctx, ctx->err);
 945         }
 946         return package;
 947 }
 948
 949 __private UCI_BACKEND(uci_file_backend, "file",
 950         .load = uci_file_load,
 951         .commit = uci_file_commit,
 952         .list_configs = uci_list_config_files,
 953 );