file.c

   1 /*
   2  * libuci - Library for the Unified Configuration Interface
   3  * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU Lesser General Public License for more details.
  13  */
  14
  15 /*
  16  * This file contains the code for parsing uci config files
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22 #include <sys/file.h>
  23 #include <stdbool.h>
  24 #include <unistd.h>
  25 #include <fcntl.h>
  26 #include <stdio.h>
  27 #include <ctype.h>
  28 #include <glob.h>
  29 #include <string.h>
  30 #include <stdlib.h>
  31
  32 #include "uci.h"
  33 #include "uci_internal.h"
  34
  35 #define LINEBUF 32
  36 #define LINEBUF_MAX     4096
  37
  38 /*
  39  * Fetch a new line from the input stream and resize buffer if necessary
  40  */
  41 __private void uci_getln(struct uci_context *ctx, int offset)
  42 {
  43         struct uci_parse_context *pctx = ctx->pctx;
  44         char *p;
  45         int ofs;
  46
  47         if (pctx->buf == NULL) {
  48                 pctx->buf = uci_malloc(ctx, LINEBUF);
  49                 pctx->bufsz = LINEBUF;
  50         }
  51         /* `offset' may off by one */
  52         if (offset >= pctx->bufsz) {
  53                 pctx->bufsz *= 2;
  54                 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
  55         }
  56
  57         ofs = offset;
  58         do {
  59                 p = &pctx->buf[ofs];
  60                 p[0] = 0;
  61
  62                 p = fgets(p, pctx->bufsz - ofs, pctx->file);
  63                 if (!p || !*p)
  64                         return;
  65
  66                 ofs += strlen(p);
  67                 if (pctx->buf[ofs - 1] == '\n') {
  68                         pctx->line++;
  69                         return;
  70                 }
  71
  72                 if (pctx->bufsz > LINEBUF_MAX/2)
  73                         uci_parse_error(ctx, "line too long");
  74
  75                 pctx->bufsz *= 2;
  76                 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
  77         } while (1);
  78 }
  79
  80 /*
  81  * parse a character escaped by '\'
  82  * returns true if the escaped character is to be parsed
  83  * returns false if the escaped character is to be ignored
  84  */
  85 static bool parse_backslash(struct uci_context *ctx)
  86 {
  87         struct uci_parse_context *pctx = ctx->pctx;
  88
  89         /* skip backslash */
  90         pctx->pos += 1;
  91
  92         /* undecoded backslash at the end of line, fetch the next line */
  93         if (!pctx_cur_char(pctx)
  94                     || pctx_cur_char(pctx) == '\n'
  95                     || (pctx_cur_char(pctx) == '\r' &&
  96                         pctx_char(pctx, pctx_pos(pctx) + 1) == '\n' &&
  97                         !pctx_char(pctx, pctx_pos(pctx) + 2))) {
  98                 uci_getln(ctx, pctx->pos);
  99                 return false;
 100         }
 101
 102         /* FIXME: decode escaped char, necessary? */
 103         return true;
 104 }
 105
 106 /*
 107  * move the string pointer forward until a non-whitespace character or
 108  * EOL is reached
 109  */
 110 static void skip_whitespace(struct uci_context *ctx)
 111 {
 112         struct uci_parse_context *pctx = ctx->pctx;
 113
 114         while (pctx_cur_char(pctx) && isspace(pctx_cur_char(pctx)))
 115                 pctx->pos += 1;
 116 }
 117
 118 static inline void addc(struct uci_context *ctx, int *pos_dest, int *pos_src)
 119 {
 120         struct uci_parse_context *pctx = ctx->pctx;
 121
 122         pctx_char(pctx, *pos_dest) = pctx_char(pctx, *pos_src);
 123         *pos_dest += 1;
 124         *pos_src += 1;
 125 }
 126
 127 /*
 128  * parse a double quoted string argument from the command line
 129  */
 130 static void parse_double_quote(struct uci_context *ctx, int *target)
 131 {
 132         struct uci_parse_context *pctx = ctx->pctx;
 133         char c;
 134
 135         /* skip quote character */
 136         pctx->pos += 1;
 137
 138         while (1) {
 139                 c = pctx_cur_char(pctx);
 140                 switch(c) {
 141                 case '"':
 142                         pctx->pos += 1;
 143                         return;
 144                 case 0:
 145                         /* Multi-line str value */
 146                         uci_getln(ctx, pctx->pos);
 147                         if (!pctx_cur_char(pctx)) {
 148                                 uci_parse_error(ctx, "EOF with unterminated \"");
 149                         }
 150                         break;
 151                 case '\\':
 152                         if (!parse_backslash(ctx))
 153                                 continue;
 154                         /* fall through */
 155                 default:
 156                         addc(ctx, target, &pctx->pos);
 157                         break;
 158                 }
 159         }
 160         uci_parse_error(ctx, "unterminated \"");
 161 }
 162
 163 /*
 164  * parse a single quoted string argument from the command line
 165  */
 166 static void parse_single_quote(struct uci_context *ctx, int *target)
 167 {
 168         struct uci_parse_context *pctx = ctx->pctx;
 169         char c;
 170         /* skip quote character */
 171         pctx->pos += 1;
 172
 173         while (1) {
 174                 c = pctx_cur_char(pctx);
 175                 switch(c) {
 176                 case '\'':
 177                         pctx->pos += 1;
 178                         return;
 179                 case 0:
 180                         /* Multi-line str value */
 181                         uci_getln(ctx, pctx->pos);
 182                         if (!pctx_cur_char(pctx)) {
 183                                 uci_parse_error(ctx, "EOF with unterminated \"");
 184                         }
 185                         break;
 186                 default:
 187                         addc(ctx, target, &pctx->pos);
 188                 }
 189         }
 190         uci_parse_error(ctx, "unterminated '");
 191 }
 192
 193 /*
 194  * parse a string from the command line and detect the quoting style
 195  */
 196 static void parse_str(struct uci_context *ctx, int *target)
 197 {
 198         struct uci_parse_context *pctx = ctx->pctx;
 199         bool next = true;
 200         do {
 201                 switch(pctx_cur_char(pctx)) {
 202                 case '\'':
 203                         parse_single_quote(ctx, target);
 204                         break;
 205                 case '"':
 206                         parse_double_quote(ctx, target);
 207                         break;
 208                 case '#':
 209                         pctx_cur_char(pctx) = 0;
 210                         /* fall through */
 211                 case 0:
 212                         goto done;
 213                 case ';':
 214                         next = false;
 215                         goto done;
 216                 case '\\':
 217                         if (!parse_backslash(ctx))
 218                                 continue;
 219                         /* fall through */
 220                 default:
 221                         addc(ctx, target, &pctx->pos);
 222                         break;
 223                 }
 224         } while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
 225 done:
 226
 227         /*
 228          * if the string was unquoted and we've stopped at a whitespace
 229          * character, skip to the next one, because the whitespace will
 230          * be overwritten by a null byte here
 231          */
 232         if (pctx_cur_char(pctx) && next)
 233                 pctx->pos += 1;
 234
 235         /* terminate the parsed string */
 236         pctx_char(pctx, *target) = 0;
 237 }
 238
 239 /*
 240  * extract the next argument from the command line
 241  */
 242 static char *next_arg(struct uci_context *ctx, bool required, bool name)
 243 {
 244         struct uci_parse_context *pctx = ctx->pctx;
 245         int val, ptr;
 246
 247         skip_whitespace(ctx);
 248         val = ptr = pctx_pos(pctx);
 249         if(pctx_cur_char(pctx) == ';') {
 250                 pctx_cur_char(pctx) = 0;
 251                 pctx->pos += 1;
 252         } else {
 253                 parse_str(ctx, &ptr);
 254         }
 255         if (!pctx_char(pctx, val)) {
 256                 if (required)
 257                         uci_parse_error(ctx, "insufficient arguments");
 258                 goto done;
 259         }
 260
 261         if (name && !uci_validate_name(pctx_str(pctx, val)))
 262                 uci_parse_error(ctx, "invalid character in name field");
 263
 264 done:
 265         return pctx_str(pctx, val);
 266 }
 267
 268 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
 269 {
 270         UCI_HANDLE_ERR(ctx);
 271         UCI_ASSERT(ctx, str != NULL);
 272         UCI_ASSERT(ctx, result != NULL);
 273
 274         if (ctx->pctx && (ctx->pctx->file != stream))
 275                 uci_cleanup(ctx);
 276
 277         if (!ctx->pctx)
 278                 uci_alloc_parse_context(ctx);
 279
 280         ctx->pctx->file = stream;
 281
 282         if (!*str) {
 283                 uci_getln(ctx, 0);
 284                 *str = ctx->pctx->buf;
 285         } else {
 286                 UCI_ASSERT(ctx, ctx->pctx->pos == *str - ctx->pctx->buf);
 287         }
 288
 289         *result = next_arg(ctx, false, false);
 290
 291         return 0;
 292 }
 293
 294 static int
 295 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
 296 {
 297         UCI_ASSERT(ctx, ptr != NULL);
 298         UCI_ASSERT(ctx, e != NULL);
 299
 300         memset(ptr, 0, sizeof(struct uci_ptr));
 301         switch(e->type) {
 302         case UCI_TYPE_OPTION:
 303                 ptr->o = uci_to_option(e);
 304                 goto fill_option;
 305         case UCI_TYPE_SECTION:
 306                 ptr->s = uci_to_section(e);
 307                 goto fill_section;
 308         case UCI_TYPE_PACKAGE:
 309                 ptr->p = uci_to_package(e);
 310                 goto fill_package;
 311         default:
 312                 UCI_THROW(ctx, UCI_ERR_INVAL);
 313         }
 314
 315 fill_option:
 316         ptr->option = ptr->o->e.name;
 317         ptr->s = ptr->o->section;
 318 fill_section:
 319         ptr->section = ptr->s->e.name;
 320         ptr->p = ptr->s->package;
 321 fill_package:
 322         ptr->package = ptr->p->e.name;
 323
 324         ptr->flags |= UCI_LOOKUP_DONE;
 325
 326         return 0;
 327 }
 328
 329
 330
 331 /*
 332  * verify that the end of the line or command is reached.
 333  * throw an error if extra arguments are given on the command line
 334  */
 335 static void assert_eol(struct uci_context *ctx)
 336 {
 337         char *tmp;
 338
 339         skip_whitespace(ctx);
 340         tmp = next_arg(ctx, false, false);
 341         if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
 342                 uci_parse_error(ctx, "too many arguments");
 343 }
 344
 345 /*
 346  * switch to a different config, either triggered by uci_load, or by a
 347  * 'package <...>' statement in the import file
 348  */
 349 static void uci_switch_config(struct uci_context *ctx)
 350 {
 351         struct uci_parse_context *pctx;
 352         struct uci_element *e;
 353         const char *name;
 354
 355         pctx = ctx->pctx;
 356         name = pctx->name;
 357
 358         /* add the last config to main config file list */
 359         if (pctx->package) {
 360                 pctx->package->backend = ctx->backend;
 361                 uci_list_add(&ctx->root, &pctx->package->e.list);
 362
 363                 pctx->package = NULL;
 364                 pctx->section = NULL;
 365         }
 366
 367         if (!name)
 368                 return;
 369
 370         /*
 371          * if an older config under the same name exists, unload it
 372          * ignore errors here, e.g. if the config was not found
 373          */
 374         e = uci_lookup_list(&ctx->root, name);
 375         if (e)
 376                 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 377         pctx->package = uci_alloc_package(ctx, name);
 378 }
 379
 380 /*
 381  * parse the 'package' uci command (next config package)
 382  */
 383 static void uci_parse_package(struct uci_context *ctx, bool single)
 384 {
 385         struct uci_parse_context *pctx = ctx->pctx;
 386         char *name = NULL;
 387
 388         /* command string null-terminated by strtok */
 389         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 390
 391         name = next_arg(ctx, true, true);
 392         assert_eol(ctx);
 393         if (single)
 394                 return;
 395
 396         ctx->pctx->name = name;
 397         uci_switch_config(ctx);
 398 }
 399
 400 /*
 401  * parse the 'config' uci command (open a section)
 402  */
 403 static void uci_parse_config(struct uci_context *ctx)
 404 {
 405         struct uci_parse_context *pctx = ctx->pctx;
 406         struct uci_element *e;
 407         struct uci_ptr ptr;
 408         char *name = NULL;
 409         char *type = NULL;
 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         type = next_arg(ctx, true, false);
 423         if (!uci_validate_type(type))
 424                 uci_parse_error(ctx, "invalid character in type field");
 425         name = next_arg(ctx, false, true);
 426         assert_eol(ctx);
 427
 428         if (!name || !name[0]) {
 429                 ctx->internal = !pctx->merge;
 430                 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
 431         } else {
 432                 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
 433                 e = uci_lookup_list(&pctx->package->sections, name);
 434                 if (e)
 435                         ptr.s = uci_to_section(e);
 436                 ptr.section = name;
 437                 ptr.value = type;
 438
 439                 ctx->internal = !pctx->merge;
 440                 UCI_NESTED(uci_set, ctx, &ptr);
 441                 pctx->section = uci_to_section(ptr.last);
 442         }
 443 }
 444
 445 /*
 446  * parse the 'option' uci command (open a value)
 447  */
 448 static void uci_parse_option(struct uci_context *ctx, bool list)
 449 {
 450         struct uci_parse_context *pctx = ctx->pctx;
 451         struct uci_element *e;
 452         struct uci_ptr ptr;
 453         char *name = NULL;
 454         char *value = NULL;
 455
 456         if (!pctx->section)
 457                 uci_parse_error(ctx, "option/list command found before the first section");
 458
 459         /* command string null-terminated by strtok */
 460         pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 461
 462         name = next_arg(ctx, true, true);
 463         value = next_arg(ctx, false, false);
 464         assert_eol(ctx);
 465
 466         uci_fill_ptr(ctx, &ptr, &pctx->section->e);
 467         e = uci_lookup_list(&pctx->section->options, name);
 468         if (e)
 469                 ptr.o = uci_to_option(e);
 470         ptr.option = name;
 471         ptr.value = value;
 472
 473         ctx->internal = !pctx->merge;
 474         if (list)
 475                 UCI_NESTED(uci_add_list, ctx, &ptr);
 476         else
 477                 UCI_NESTED(uci_set, ctx, &ptr);
 478 }
 479
 480 /*
 481  * parse a complete input line, split up combined commands by ';'
 482  */
 483 static void uci_parse_line(struct uci_context *ctx, bool single)
 484 {
 485         struct uci_parse_context *pctx = ctx->pctx;
 486         char *word;
 487
 488         /* Skip whitespace characters at the start of line */
 489         skip_whitespace(ctx);
 490         do {
 491                 word = strtok(pctx_cur_str(pctx), " \t");
 492                 if (!word)
 493                         return;
 494
 495                 switch(word[0]) {
 496                         case 0:
 497                         case '#':
 498                                 return;
 499                         case 'p':
 500                                 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
 501                                         uci_parse_package(ctx, single);
 502                                 else
 503                                         goto invalid;
 504                                 break;
 505                         case 'c':
 506                                 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
 507                                         uci_parse_config(ctx);
 508                                 else
 509                                         goto invalid;
 510                                 break;
 511                         case 'o':
 512                                 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
 513                                         uci_parse_option(ctx, false);
 514                                 else
 515                                         goto invalid;
 516                                 break;
 517                         case 'l':
 518                                 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
 519                                         uci_parse_option(ctx, true);
 520                                 else
 521                                         goto invalid;
 522                                 break;
 523                         default:
 524                                 goto invalid;
 525                 }
 526                 continue;
 527 invalid:
 528                 uci_parse_error(ctx, "invalid command");
 529         } while (1);
 530 }
 531
 532 /* max number of characters that escaping adds to the string */
 533 #define UCI_QUOTE_ESCAPE        "'\\''"
 534
 535 /*
 536  * escape an uci string for export
 537  */
 538 static const char *uci_escape(struct uci_context *ctx, const char *str)
 539 {
 540         const char *end;
 541         int ofs = 0;
 542
 543         if (!ctx->buf) {
 544                 ctx->bufsz = LINEBUF;
 545                 ctx->buf = malloc(LINEBUF);
 546
 547                 if (!ctx->buf)
 548                         return str;
 549         }
 550
 551         while (1) {
 552                 int len;
 553
 554                 end = strchr(str, '\'');
 555                 if (!end)
 556                         end = str + strlen(str);
 557                 len = end - str;
 558
 559                 /* make sure that we have enough room in the buffer */
 560                 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
 561                         ctx->bufsz *= 2;
 562                         ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
 563                 }
 564
 565                 /* copy the string until the character before the quote */
 566                 memcpy(&ctx->buf[ofs], str, len);
 567                 ofs += len;
 568
 569                 /* end of string? return the buffer */
 570                 if (*end == 0)
 571                         break;
 572
 573                 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
 574                 ofs += strlen(&ctx->buf[ofs]);
 575                 str = end + 1;
 576         }
 577
 578         ctx->buf[ofs] = 0;
 579         return ctx->buf;
 580 }
 581
 582 /*
 583  * export a single config package to a file stream
 584  */
 585 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 586 {
 587         struct uci_context *ctx = p->ctx;
 588         struct uci_element *s, *o, *i;
 589
 590         if (header)
 591                 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
 592         uci_foreach_element(&p->sections, s) {
 593                 struct uci_section *sec = uci_to_section(s);
 594                 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
 595                 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
 596                         fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 597                 fprintf(stream, "\n");
 598                 uci_foreach_element(&sec->options, o) {
 599                         struct uci_option *opt = uci_to_option(o);
 600                         switch(opt->type) {
 601                         case UCI_TYPE_STRING:
 602                                 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
 603                                 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
 604                                 break;
 605                         case UCI_TYPE_LIST:
 606                                 uci_foreach_element(&opt->v.list, i) {
 607                                         fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
 608                                         fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
 609                                 }
 610                                 break;
 611                         default:
 612                                 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
 613                                 break;
 614                         }
 615                 }
 616         }
 617         fprintf(stream, "\n");
 618 }
 619
 620 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
 621 {
 622         struct uci_element *e;
 623
 624         UCI_HANDLE_ERR(ctx);
 625         UCI_ASSERT(ctx, stream != NULL);
 626
 627         if (package)
 628                 uci_export_package(package, stream, header);
 629         else {
 630                 uci_foreach_element(&ctx->root, e) {
 631                         uci_export_package(uci_to_package(e), stream, header);
 632                 }
 633         }
 634
 635         return 0;
 636 }
 637
 638 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
 639 {
 640         struct uci_parse_context *pctx;
 641         UCI_HANDLE_ERR(ctx);
 642
 643         /* make sure no memory from previous parse attempts is leaked */
 644         uci_cleanup(ctx);
 645
 646         uci_alloc_parse_context(ctx);
 647         pctx = ctx->pctx;
 648         pctx->file = stream;
 649         if (package && *package && single) {
 650                 pctx->package = *package;
 651                 pctx->merge = true;
 652         }
 653
 654         /*
 655          * If 'name' was supplied, assume that the supplied stream does not contain
 656          * the appropriate 'package <name>' string to specify the config name
 657          * NB: the config file can still override the package name
 658          */
 659         if (name) {
 660                 UCI_ASSERT(ctx, uci_validate_package(name));
 661                 pctx->name = name;
 662         }
 663
 664         while (!feof(pctx->file)) {
 665                 pctx->pos = 0;
 666                 uci_getln(ctx, 0);
 667                 UCI_TRAP_SAVE(ctx, error);
 668                 if (pctx->buf[0])
 669                         uci_parse_line(ctx, single);
 670                 UCI_TRAP_RESTORE(ctx);
 671                 continue;
 672 error:
 673                 if (ctx->flags & UCI_FLAG_PERROR)
 674                         uci_perror(ctx, NULL);
 675                 if ((ctx->err != UCI_ERR_PARSE) ||
 676                         (ctx->flags & UCI_FLAG_STRICT))
 677                         UCI_THROW(ctx, ctx->err);
 678         }
 679
 680         uci_fixup_section(ctx, ctx->pctx->section);
 681         if (!pctx->package && name)
 682                 uci_switch_config(ctx);
 683         if (package)
 684                 *package = pctx->package;
 685         if (pctx->merge)
 686                 pctx->package = NULL;
 687
 688         pctx->name = NULL;
 689         uci_switch_config(ctx);
 690
 691         /* no error happened, we can get rid of the parser context now */
 692         uci_cleanup(ctx);
 693
 694         return 0;
 695 }
 696
 697
 698 static char *uci_config_path(struct uci_context *ctx, const char *name)
 699 {
 700         char *filename;
 701
 702         UCI_ASSERT(ctx, uci_validate_package(name));
 703         filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
 704         sprintf(filename, "%s/%s", ctx->confdir, name);
 705
 706         return filename;
 707 }
 708
 709 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 710 {
 711         struct uci_package *p = *package;
 712         FILE *f1, *f2 = NULL;
 713         char *name = NULL;
 714         char *path = NULL;
 715         char *filename = NULL;
 716         struct stat statbuf;
 717         bool do_rename = false;
 718
 719         if (!p->path) {
 720                 if (overwrite)
 721                         p->path = uci_config_path(ctx, p->e.name);
 722                 else
 723                         UCI_THROW(ctx, UCI_ERR_INVAL);
 724         }
 725
 726         if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
 727                 UCI_THROW(ctx, UCI_ERR_MEM);
 728
 729         if (!mktemp(filename))
 730                 *filename = 0;
 731
 732         if (!*filename) {
 733                 free(filename);
 734                 UCI_THROW(ctx, UCI_ERR_IO);
 735         }
 736
 737         if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
 738                 UCI_THROW(ctx, UCI_ERR_IO);
 739
 740         /* open the config file for writing now, so that it is locked */
 741         f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
 742
 743         /* flush unsaved changes and reload from delta file */
 744         UCI_TRAP_SAVE(ctx, done);
 745         if (p->has_delta) {
 746                 if (!overwrite) {
 747                         name = uci_strdup(ctx, p->e.name);
 748                         path = uci_strdup(ctx, p->path);
 749                         /* dump our own changes to the delta file */
 750                         if (!uci_list_empty(&p->delta))
 751                                 UCI_INTERNAL(uci_save, ctx, p);
 752
 753                         /*
 754                          * other processes might have modified the config
 755                          * as well. dump and reload
 756                          */
 757                         uci_free_package(&p);
 758                         uci_cleanup(ctx);
 759                         UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
 760
 761                         p->path = path;
 762                         p->has_delta = true;
 763                         *package = p;
 764
 765                         /* freed together with the uci_package */
 766                         path = NULL;
 767                 }
 768
 769                 /* flush delta */
 770                 if (!uci_load_delta(ctx, p, true))
 771                         goto done;
 772         }
 773
 774         f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
 775         uci_export(ctx, f2, p, false);
 776
 777         fflush(f2);
 778         fsync(fileno(f2));
 779         uci_close_stream(f2);
 780
 781         do_rename = true;
 782
 783         UCI_TRAP_RESTORE(ctx);
 784
 785 done:
 786         free(name);
 787         free(path);
 788         uci_close_stream(f1);
 789         if (do_rename && rename(filename, p->path)) {
 790                 unlink(filename);
 791                 UCI_THROW(ctx, UCI_ERR_IO);
 792         }
 793         free(filename);
 794         sync();
 795         if (ctx->err)
 796                 UCI_THROW(ctx, ctx->err);
 797 }
 798
 799
 800 /*
 801  * This function returns the filename by returning the string
 802  * after the last '/' character. By checking for a non-'\0'
 803  * character afterwards, directories are ignored (glob marks
 804  * those with a trailing '/'
 805  */
 806 static inline char *get_filename(char *path)
 807 {
 808         char *p;
 809
 810         p = strrchr(path, '/');
 811         p++;
 812         if (!*p)
 813                 return NULL;
 814         return p;
 815 }
 816
 817 static char **uci_list_config_files(struct uci_context *ctx)
 818 {
 819         char **configs;
 820         glob_t globbuf;
 821         int size, i;
 822         char *buf;
 823         char *dir;
 824
 825         dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
 826         sprintf(dir, "%s/*", ctx->confdir);
 827         if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
 828                 free(dir);
 829                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 830         }
 831
 832         size = sizeof(char *) * (globbuf.gl_pathc + 1);
 833         for(i = 0; i < globbuf.gl_pathc; i++) {
 834                 char *p;
 835
 836                 p = get_filename(globbuf.gl_pathv[i]);
 837                 if (!p)
 838                         continue;
 839
 840                 size += strlen(p) + 1;
 841         }
 842
 843         configs = uci_malloc(ctx, size);
 844         buf = (char *) &configs[globbuf.gl_pathc + 1];
 845         for(i = 0; i < globbuf.gl_pathc; i++) {
 846                 char *p;
 847
 848                 p = get_filename(globbuf.gl_pathv[i]);
 849                 if (!p)
 850                         continue;
 851
 852                 if (!uci_validate_package(p))
 853                         continue;
 854
 855                 configs[i] = buf;
 856                 strcpy(buf, p);
 857                 buf += strlen(buf) + 1;
 858         }
 859         free(dir);
 860         globfree(&globbuf);
 861         return configs;
 862 }
 863
 864 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
 865 {
 866         struct uci_package *package = NULL;
 867         char *filename;
 868         bool confdir;
 869         FILE *file = NULL;
 870
 871         switch (name[0]) {
 872         case '.':
 873                 /* relative path outside of /etc/config */
 874                 if (name[1] != '/')
 875                         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 876                 /* fall through */
 877         case '/':
 878                 /* absolute path outside of /etc/config */
 879                 filename = uci_strdup(ctx, name);
 880                 name = strrchr(name, '/') + 1;
 881                 confdir = false;
 882                 break;
 883         default:
 884                 /* config in /etc/config */
 885                 filename = uci_config_path(ctx, name);
 886                 confdir = true;
 887                 break;
 888         }
 889
 890         UCI_TRAP_SAVE(ctx, done);
 891         file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
 892         ctx->err = 0;
 893         UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
 894         UCI_TRAP_RESTORE(ctx);
 895
 896         if (package) {
 897                 package->path = filename;
 898                 package->has_delta = confdir;
 899                 uci_load_delta(ctx, package, false);
 900         }
 901
 902 done:
 903         uci_close_stream(file);
 904         if (ctx->err) {
 905                 free(filename);
 906                 UCI_THROW(ctx, ctx->err);
 907         }
 908         return package;
 909 }
 910
 911 __private UCI_BACKEND(uci_file_backend, "file",
 912         .load = uci_file_load,
 913         .commit = uci_file_commit,
 914         .list_configs = uci_list_config_files,
 915 );