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         uci_fixup_section(ctx, ctx->pctx->section);
 412         if (!ctx->pctx->package) {
 413                 if (!ctx->pctx->name)
 414                         uci_parse_error(ctx, "attempting to import a file without a package name");
 415
 416                 uci_switch_config(ctx);
 417         }
 418
 419         /* command string null-terminated by strtok */
 420         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 421
 422         ofs_type = next_arg(ctx, true, false, false);
 423         type = pctx_str(pctx, ofs_type);
 424         if (!uci_validate_type(type))
 425                 uci_parse_error(ctx, "invalid character in type field");
 426
 427         ofs_name = next_arg(ctx, false, true, false);
 428         type = pctx_str(pctx, ofs_type);
 429         name = pctx_str(pctx, ofs_name);
 430         assert_eol(ctx);
 431
 432         if (!name || !name[0]) {
 433                 ctx->internal = !pctx->merge;
 434                 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
 435         } else {
 436                 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
 437                 e = uci_lookup_list(&pctx->package->sections, name);
 438                 if (e) {
 439                         ptr.s = uci_to_section(e);
 440
 441                         if ((ctx->flags & UCI_FLAG_STRICT) && strcmp(ptr.s->type, type))
 442                                 uci_parse_error(ctx, "section of different type overwrites prior section with same name");
 443                 }
 444
 445                 ptr.section = name;
 446                 ptr.value = type;
 447
 448                 ctx->internal = !pctx->merge;
 449                 UCI_NESTED(uci_set, ctx, &ptr);
 450                 pctx->section = uci_to_section(ptr.last);
 451         }
 452 }
 453
 454 /*
 455  * parse the 'option' uci command (open a value)
 456  */
 457 static void uci_parse_option(struct uci_context *ctx, bool list)
 458 {
 459         struct uci_parse_context *pctx = ctx->pctx;
 460         struct uci_element *e;
 461         struct uci_ptr ptr;
 462         int ofs_name, ofs_value;
 463         char *name = NULL;
 464         char *value = NULL;
 465
 466         if (!pctx->section)
 467                 uci_parse_error(ctx, "option/list command found before the first section");
 468
 469         /* command string null-terminated by strtok */
 470         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 471
 472         ofs_name = next_arg(ctx, true, true, false);
 473         ofs_value = next_arg(ctx, false, false, false);
 474         name = pctx_str(pctx, ofs_name);
 475         value = pctx_str(pctx, ofs_value);
 476         assert_eol(ctx);
 477
 478         uci_fill_ptr(ctx, &ptr, &pctx->section->e);
 479         e = uci_lookup_list(&pctx->section->options, name);
 480         if (e)
 481                 ptr.o = uci_to_option(e);
 482         ptr.option = name;
 483         ptr.value = value;
 484
 485         ctx->internal = !pctx->merge;
 486         if (list)
 487                 UCI_NESTED(uci_add_list, ctx, &ptr);
 488         else
 489                 UCI_NESTED(uci_set, ctx, &ptr);
 490 }
 491
 492 /*
 493  * parse a complete input line, split up combined commands by ';'
 494  */
 495 static void uci_parse_line(struct uci_context *ctx, bool single)
 496 {
 497         struct uci_parse_context *pctx = ctx->pctx;
 498         char *word;
 499
 500         /* Skip whitespace characters at the start of line */
 501         skip_whitespace(ctx);
 502         do {
 503                 word = strtok(pctx_cur_str(pctx), " \t");
 504                 if (!word)
 505                         return;
 506
 507                 switch(word[0]) {
 508                         case 0:
 509                         case '#':
 510                                 return;
 511                         case 'p':
 512                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 513                                         uci_parse_package(ctx, single);
 514                                 else
 515                                         goto invalid;
 516                                 break;
 517                         case 'c':
 518                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 519                                         uci_parse_config(ctx);
 520                                 else
 521                                         goto invalid;
 522                                 break;
 523                         case 'o':
 524                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 525                                         uci_parse_option(ctx, false);
 526                                 else
 527                                         goto invalid;
 528                                 break;
 529                         case 'l':
 530                                 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
 531                                         uci_parse_option(ctx, true);
 532                                 else
 533                                         goto invalid;
 534                                 break;
 535                         default:
 536                                 goto invalid;
 537                 }
 538                 continue;
 539 invalid:
 540                 uci_parse_error(ctx, "invalid command");
 541         } while (1);
 542 }
 543
 544 /* max number of characters that escaping adds to the string */
 545 #define UCI_QUOTE_ESCAPE        "'\\''"
 546
 547 /*
 548  * escape an uci string for export
 549  */
 550 static const char *uci_escape(struct uci_context *ctx, const char *str)
 551 {
 552         const char *end;
 553         int ofs = 0;
 554
 555         if (!ctx->buf) {
 556                 ctx->bufsz = LINEBUF;
 557                 ctx->buf = malloc(LINEBUF);
 558
 559                 if (!ctx->buf)
 560                         return str;
 561         }
 562
 563         while (1) {
 564                 int len;
 565
 566                 end = strchr(str, '\'');
 567                 if (!end)
 568                         end = str + strlen(str);
 569                 len = end - str;
 570
 571                 /* make sure that we have enough room in the buffer */
 572                 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
 573                         ctx->bufsz *= 2;
 574                         ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
 575                 }
 576
 577                 /* copy the string until the character before the quote */
 578                 memcpy(&ctx->buf[ofs], str, len);
 579                 ofs += len;
 580
 581                 /* end of string? return the buffer */
 582                 if (*end == 0)
 583                         break;
 584
 585                 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
 586                 ofs += strlen(&ctx->buf[ofs]);
 587                 str = end + 1;
 588         }
 589
 590         ctx->buf[ofs] = 0;
 591         return ctx->buf;
 592 }
 593
 594 /*
 595  * export a single config package to a file stream
 596  */
 597 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 598 {
 599         struct uci_context *ctx = p->ctx;
 600         struct uci_element *s, *o, *i;
 601
 602         if (header)
 603                 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
 604         uci_foreach_element(&p->sections, s) {
 605                 struct uci_section *sec = uci_to_section(s);
 606                 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
 607                 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
 608                         fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 609                 fprintf(stream, "\n");
 610                 uci_foreach_element(&sec->options, o) {
 611                         struct uci_option *opt = uci_to_option(o);
 612                         switch(opt->type) {
 613                         case UCI_TYPE_STRING:
 614                                 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
 615                                 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
 616                                 break;
 617                         case UCI_TYPE_LIST:
 618                                 uci_foreach_element(&opt->v.list, i) {
 619                                         fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
 620                                         fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
 621                                 }
 622                                 break;
 623                         default:
 624                                 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
 625                                 break;
 626                         }
 627                 }
 628         }
 629         fprintf(stream, "\n");
 630 }
 631
 632 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 633 {
 634         struct uci_element *e;
 635
 636         UCI_HANDLE_ERR(ctx);
 637         UCI_ASSERT(ctx, stream != NULL);
 638
 639         if (package)
 640                 uci_export_package(package, stream, header);
 641         else {
 642                 uci_foreach_element(&ctx->root, e) {
 643                         uci_export_package(uci_to_package(e), stream, header);
 644                 }
 645         }
 646
 647         return 0;
 648 }
 649
 650 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 651 {
 652         struct uci_parse_context *pctx;
 653         UCI_HANDLE_ERR(ctx);
 654
 655         /* make sure no memory from previous parse attempts is leaked */
 656         uci_cleanup(ctx);
 657
 658         uci_alloc_parse_context(ctx);
 659         pctx = ctx->pctx;
 660         pctx->file = stream;
 661         if (package && *package && single) {
 662                 pctx->package = *package;
 663                 pctx->merge = true;
 664         }
 665
 666         /*
 667          * If 'name' was supplied, assume that the supplied stream does not contain
 668          * the appropriate 'package <name>' string to specify the config name
 669          * NB: the config file can still override the package name
 670          */
 671         if (name) {
 672                 UCI_ASSERT(ctx, uci_validate_package(name));
 673                 pctx->name = name;
 674         }
 675
 676         while (!feof(pctx->file)) {
 677                 pctx->pos = 0;
 678                 uci_getln(ctx, 0);
 679                 UCI_TRAP_SAVE(ctx, error);
 680                 if (pctx->buf[0])
 681                         uci_parse_line(ctx, single);
 682                 UCI_TRAP_RESTORE(ctx);
 683                 continue;
 684 error:
 685                 if (ctx->flags & UCI_FLAG_PERROR)
 686                         uci_perror(ctx, NULL);
 687                 if ((ctx->err != UCI_ERR_PARSE) ||
 688                         (ctx->flags & UCI_FLAG_STRICT))
 689                         UCI_THROW(ctx, ctx->err);
 690         }
 691
 692         uci_fixup_section(ctx, ctx->pctx->section);
 693         if (!pctx->package && name)
 694                 uci_switch_config(ctx);
 695         if (package)
 696                 *package = pctx->package;
 697         if (pctx->merge)
 698                 pctx->package = NULL;
 699
 700         pctx->name = NULL;
 701         uci_switch_config(ctx);
 702
 703         /* no error happened, we can get rid of the parser context now */
 704         uci_cleanup(ctx);
 705
 706         return 0;
 707 }
 708
 709
 710 static char *uci_config_path(struct uci_context *ctx, const char *name)
 711 {
 712         char *filename;
 713
 714         UCI_ASSERT(ctx, uci_validate_package(name));
 715         filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
 716         sprintf(filename, "%s/%s", ctx->confdir, name);
 717
 718         return filename;
 719 }
 720
 721 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 722 {
 723         struct uci_package *p = *package;
 724         FILE *f1, *f2 = NULL;
 725         char *name = NULL;
 726         char *path = NULL;
 727         char *filename = NULL;
 728         struct stat statbuf;
 729         bool do_rename = false;
 730
 731         if (!p->path) {
 732                 if (overwrite)
 733                         p->path = uci_config_path(ctx, p->e.name);
 734                 else
 735                         UCI_THROW(ctx, UCI_ERR_INVAL);
 736         }
 737
 738         if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
 739                 UCI_THROW(ctx, UCI_ERR_MEM);
 740
 741         /* open the config file for writing now, so that it is locked */
 742         f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
 743
 744         /* flush unsaved changes and reload from delta file */
 745         UCI_TRAP_SAVE(ctx, done);
 746         if (p->has_delta) {
 747                 if (!overwrite) {
 748                         name = uci_strdup(ctx, p->e.name);
 749                         path = uci_strdup(ctx, p->path);
 750                         /* dump our own changes to the delta file */
 751                         if (!uci_list_empty(&p->delta))
 752                                 UCI_INTERNAL(uci_save, ctx, p);
 753
 754                         /*
 755                          * other processes might have modified the config
 756                          * as well. dump and reload
 757                          */
 758                         uci_free_package(&p);
 759                         uci_cleanup(ctx);
 760                         UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
 761
 762                         p->path = path;
 763                         p->has_delta = true;
 764                         *package = p;
 765
 766                         /* freed together with the uci_package */
 767                         path = NULL;
 768                 }
 769
 770                 /* flush delta */
 771                 if (!uci_load_delta(ctx, p, true))
 772                         goto done;
 773         }
 774
 775         if (!mktemp(filename))
 776                 *filename = 0;
 777
 778         if (!*filename) {
 779                 free(filename);
 780                 UCI_THROW(ctx, UCI_ERR_IO);
 781         }
 782
 783         if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
 784                 UCI_THROW(ctx, UCI_ERR_IO);
 785
 786         f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
 787         uci_export(ctx, f2, p, false);
 788
 789         fflush(f2);
 790         fsync(fileno(f2));
 791         uci_close_stream(f2);
 792
 793         do_rename = true;
 794
 795         UCI_TRAP_RESTORE(ctx);
 796
 797 done:
 798         free(name);
 799         free(path);
 800         uci_close_stream(f1);
 801         if (do_rename) {
 802                 path = realpath(p->path, NULL);
 803                 if (!path || rename(filename, path)) {
 804                         unlink(filename);
 805                         UCI_THROW(ctx, UCI_ERR_IO);
 806                 }
 807                 free(path);
 808         }
 809         free(filename);
 810         if (ctx->err)
 811                 UCI_THROW(ctx, ctx->err);
 812 }
 813
 814
 815 /*
 816  * This function returns the filename by returning the string
 817  * after the last '/' character. By checking for a non-'\0'
 818  * character afterwards, directories are ignored (glob marks
 819  * those with a trailing '/'
 820  */
 821 static inline char *get_filename(char *path)
 822 {
 823         char *p;
 824
 825         p = strrchr(path, '/');
 826         p++;
 827         if (!*p)
 828                 return NULL;
 829         return p;
 830 }
 831
 832 static char **uci_list_config_files(struct uci_context *ctx)
 833 {
 834         char **configs;
 835         glob_t globbuf;
 836         int size, i, j, skipped;
 837         char *buf;
 838         char *dir;
 839
 840         dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
 841         sprintf(dir, "%s/*", ctx->confdir);
 842         if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
 843                 free(dir);
 844                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 845         }
 846
 847         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 848         skipped = 0;
 849         for(i = 0; i < globbuf.gl_pathc; i++) {
 850                 char *p;
 851
 852                 p = get_filename(globbuf.gl_pathv[i]);
 853                 if (!p) {
 854                         skipped++;
 855                         continue;
 856                 }
 857
 858                 size += strlen(p) + 1;
 859         }
 860
 861         configs = uci_malloc(ctx, size - skipped);
 862         buf = (char *) &configs[globbuf.gl_pathc + 1 - skipped];
 863         j = 0;
 864         for(i = 0; i < globbuf.gl_pathc; i++) {
 865                 char *p;
 866
 867                 p = get_filename(globbuf.gl_pathv[i]);
 868                 if (!p)
 869                         continue;
 870
 871                 if (!uci_validate_package(p))
 872                         continue;
 873
 874                 configs[j++] = buf;
 875                 strcpy(buf, p);
 876                 buf += strlen(buf) + 1;
 877         }
 878         free(dir);
 879         globfree(&globbuf);
 880         return configs;
 881 }
 882
 883 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
 884 {
 885         struct uci_package *package = NULL;
 886         char *filename;
 887         bool confdir;
 888         FILE *file = NULL;
 889
 890         switch (name[0]) {
 891         case '.':
 892                 /* relative path outside of /etc/config */
 893                 if (name[1] != '/')
 894                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 895                 /* fall through */
 896         case '/':
 897                 /* absolute path outside of /etc/config */
 898                 filename = uci_strdup(ctx, name);
 899                 name = strrchr(name, '/') + 1;
 900                 confdir = false;
 901                 break;
 902         default:
 903                 /* config in /etc/config */
 904                 filename = uci_config_path(ctx, name);
 905                 confdir = true;
 906                 break;
 907         }
 908
 909         UCI_TRAP_SAVE(ctx, done);
 910         file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
 911         ctx->err = 0;
 912         UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
 913         UCI_TRAP_RESTORE(ctx);
 914
 915         if (package) {
 916                 package->path = filename;
 917                 package->has_delta = confdir;
 918                 uci_load_delta(ctx, package, false);
 919         }
 920
 921 done:
 922         uci_close_stream(file);
 923         if (ctx->err) {
 924                 free(filename);
 925                 UCI_THROW(ctx, ctx->err);
 926         }
 927         return package;
 928 }
 929
 930 __private UCI_BACKEND(uci_file_backend, "file",
 931         .load = uci_file_load,
 932         .commit = uci_file_commit,
 933         .list_configs = uci_list_config_files,
 934 );