2 * libuci - Library for the Unified Configuration Interface
3 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
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
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 General Public License for more details.
16 * This file contains the code for parsing uci config files
20 #include <sys/types.h>
32 #include "uci_internal.h"
35 #define LINEBUF_MAX 4096
38 * Fetch a new line from the input stream and resize buffer if necessary
40 __private void uci_getln(struct uci_context *ctx, int offset)
42 struct uci_parse_context *pctx = ctx->pctx;
46 if (pctx->buf == NULL) {
47 pctx->buf = uci_malloc(ctx, LINEBUF);
48 pctx->bufsz = LINEBUF;
56 p = fgets(p, pctx->bufsz - ofs, pctx->file);
61 if (pctx->buf[ofs - 1] == '\n') {
63 pctx->buf[ofs - 1] = 0;
67 if (pctx->bufsz > LINEBUF_MAX/2)
68 uci_parse_error(ctx, p, "line too long");
71 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
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
81 static inline bool parse_backslash(struct uci_context *ctx, char **str)
86 /* undecoded backslash at the end of line, fetch the next line */
89 uci_getln(ctx, *str - ctx->pctx->buf);
93 /* FIXME: decode escaped char, necessary? */
98 * move the string pointer forward until a non-whitespace character or
101 static void skip_whitespace(struct uci_context *ctx, char **str)
104 while (**str && isspace(**str))
108 if (!parse_backslash(ctx, str))
113 static inline void addc(char **dest, char **src)
121 * parse a double quoted string argument from the command line
123 static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
127 /* skip quote character */
130 while ((c = **str)) {
137 if (!parse_backslash(ctx, str))
145 uci_parse_error(ctx, *str, "unterminated \"");
149 * parse a single quoted string argument from the command line
151 static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
154 /* skip quote character */
157 while ((c = **str)) {
167 uci_parse_error(ctx, *str, "unterminated '");
171 * parse a string from the command line and detect the quoting style
173 static void parse_str(struct uci_context *ctx, char **str, char **target)
179 parse_single_quote(ctx, str, target);
182 parse_double_quote(ctx, str, target);
193 if (!parse_backslash(ctx, str))
200 } while (**str && !isspace(**str));
204 * if the string was unquoted and we've stopped at a whitespace
205 * character, skip to the next one, because the whitespace will
206 * be overwritten by a null byte here
211 /* terminate the parsed string */
216 * extract the next argument from the command line
218 static char *next_arg(struct uci_context *ctx, char **str, bool required, bool name)
224 skip_whitespace(ctx, str);
229 parse_str(ctx, str, &ptr);
233 uci_parse_error(ctx, *str, "insufficient arguments");
237 if (name && !uci_validate_name(val))
238 uci_parse_error(ctx, val, "invalid character in field");
244 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
247 UCI_ASSERT(ctx, str != NULL);
248 UCI_ASSERT(ctx, result != NULL);
250 if (ctx->pctx && (ctx->pctx->file != stream))
254 uci_alloc_parse_context(ctx);
256 ctx->pctx->file = stream;
260 *str = ctx->pctx->buf;
263 *result = next_arg(ctx, str, false, false);
269 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
271 UCI_ASSERT(ctx, ptr != NULL);
272 UCI_ASSERT(ctx, e != NULL);
274 memset(ptr, 0, sizeof(struct uci_ptr));
276 case UCI_TYPE_OPTION:
277 ptr->o = uci_to_option(e);
279 case UCI_TYPE_SECTION:
280 ptr->s = uci_to_section(e);
282 case UCI_TYPE_PACKAGE:
283 ptr->p = uci_to_package(e);
286 UCI_THROW(ctx, UCI_ERR_INVAL);
290 ptr->option = ptr->o->e.name;
291 ptr->s = ptr->o->section;
293 ptr->section = ptr->s->e.name;
294 ptr->p = ptr->s->package;
296 ptr->package = ptr->p->e.name;
298 ptr->flags |= UCI_LOOKUP_DONE;
306 * verify that the end of the line or command is reached.
307 * throw an error if extra arguments are given on the command line
309 static void assert_eol(struct uci_context *ctx, char **str)
313 skip_whitespace(ctx, str);
314 tmp = next_arg(ctx, str, false, false);
315 if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
316 uci_parse_error(ctx, *str, "too many arguments");
320 * switch to a different config, either triggered by uci_load, or by a
321 * 'package <...>' statement in the import file
323 static void uci_switch_config(struct uci_context *ctx)
325 struct uci_parse_context *pctx;
326 struct uci_element *e;
332 /* add the last config to main config file list */
334 pctx->package->backend = ctx->backend;
335 uci_list_add(&ctx->root, &pctx->package->e.list);
337 pctx->package = NULL;
338 pctx->section = NULL;
345 * if an older config under the same name exists, unload it
346 * ignore errors here, e.g. if the config was not found
348 e = uci_lookup_list(&ctx->root, name);
350 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
351 pctx->package = uci_alloc_package(ctx, name);
355 * parse the 'package' uci command (next config package)
357 static void uci_parse_package(struct uci_context *ctx, char **str, bool single)
361 /* command string null-terminated by strtok */
362 *str += strlen(*str) + 1;
364 name = next_arg(ctx, str, true, true);
365 assert_eol(ctx, str);
369 ctx->pctx->name = name;
370 uci_switch_config(ctx);
374 * parse the 'config' uci command (open a section)
376 static void uci_parse_config(struct uci_context *ctx, char **str)
378 struct uci_parse_context *pctx = ctx->pctx;
379 struct uci_element *e;
384 uci_fixup_section(ctx, ctx->pctx->section);
385 if (!ctx->pctx->package) {
386 if (!ctx->pctx->name)
387 uci_parse_error(ctx, *str, "attempting to import a file without a package name");
389 uci_switch_config(ctx);
392 /* command string null-terminated by strtok */
393 *str += strlen(*str) + 1;
395 type = next_arg(ctx, str, true, false);
396 if (!uci_validate_type(type))
397 uci_parse_error(ctx, type, "invalid character in field");
398 name = next_arg(ctx, str, false, true);
399 assert_eol(ctx, str);
402 ctx->internal = !pctx->merge;
403 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
405 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
406 e = uci_lookup_list(&pctx->package->sections, name);
408 ptr.s = uci_to_section(e);
412 ctx->internal = !pctx->merge;
413 UCI_NESTED(uci_set, ctx, &ptr);
414 pctx->section = uci_to_section(ptr.last);
419 * parse the 'option' uci command (open a value)
421 static void uci_parse_option(struct uci_context *ctx, char **str, bool list)
423 struct uci_parse_context *pctx = ctx->pctx;
424 struct uci_element *e;
430 uci_parse_error(ctx, *str, "option/list command found before the first section");
432 /* command string null-terminated by strtok */
433 *str += strlen(*str) + 1;
435 name = next_arg(ctx, str, true, true);
436 value = next_arg(ctx, str, false, false);
437 assert_eol(ctx, str);
439 uci_fill_ptr(ctx, &ptr, &pctx->section->e);
440 e = uci_lookup_list(&pctx->section->options, name);
442 ptr.o = uci_to_option(e);
446 ctx->internal = !pctx->merge;
448 UCI_NESTED(uci_add_list, ctx, &ptr);
450 UCI_NESTED(uci_set, ctx, &ptr);
454 * parse a complete input line, split up combined commands by ';'
456 static void uci_parse_line(struct uci_context *ctx, bool single)
458 struct uci_parse_context *pctx = ctx->pctx;
464 word = strtok_r(word, " \t", &brk);
473 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
474 uci_parse_package(ctx, &word, single);
479 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
480 uci_parse_config(ctx, &word);
485 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
486 uci_parse_option(ctx, &word, false);
491 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
492 uci_parse_option(ctx, &word, true);
501 uci_parse_error(ctx, word, "invalid command");
505 /* max number of characters that escaping adds to the string */
506 #define UCI_QUOTE_ESCAPE "'\\''"
509 * escape an uci string for export
511 static char *uci_escape(struct uci_context *ctx, const char *str)
517 ctx->bufsz = LINEBUF;
518 ctx->buf = malloc(LINEBUF);
524 end = strchr(str, '\'');
526 end = str + strlen(str);
529 /* make sure that we have enough room in the buffer */
530 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
532 ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
535 /* copy the string until the character before the quote */
536 memcpy(&ctx->buf[ofs], str, len);
539 /* end of string? return the buffer */
543 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
544 ofs += strlen(&ctx->buf[ofs]);
553 * export a single config package to a file stream
555 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
557 struct uci_context *ctx = p->ctx;
558 struct uci_element *s, *o, *i;
561 fprintf(stream, "package '%s'\n", uci_escape(ctx, p->e.name));
562 uci_foreach_element(&p->sections, s) {
563 struct uci_section *sec = uci_to_section(s);
564 fprintf(stream, "\nconfig '%s'", uci_escape(ctx, sec->type));
565 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
566 fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
567 fprintf(stream, "\n");
568 uci_foreach_element(&sec->options, o) {
569 struct uci_option *opt = uci_to_option(o);
571 case UCI_TYPE_STRING:
572 fprintf(stream, "\toption '%s'", uci_escape(ctx, opt->e.name));
573 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
576 uci_foreach_element(&opt->v.list, i) {
577 fprintf(stream, "\tlist '%s'", uci_escape(ctx, opt->e.name));
578 fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
582 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
587 fprintf(stream, "\n");
590 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
592 struct uci_element *e;
595 UCI_ASSERT(ctx, stream != NULL);
598 uci_export_package(package, stream, header);
600 uci_foreach_element(&ctx->root, e) {
601 uci_export_package(uci_to_package(e), stream, header);
608 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
610 struct uci_parse_context *pctx;
613 /* make sure no memory from previous parse attempts is leaked */
616 uci_alloc_parse_context(ctx);
619 if (*package && single) {
620 pctx->package = *package;
625 * If 'name' was supplied, assume that the supplied stream does not contain
626 * the appropriate 'package <name>' string to specify the config name
627 * NB: the config file can still override the package name
630 UCI_ASSERT(ctx, uci_validate_package(name));
634 while (!feof(pctx->file)) {
636 UCI_TRAP_SAVE(ctx, error);
638 uci_parse_line(ctx, single);
639 UCI_TRAP_RESTORE(ctx);
642 if (ctx->flags & UCI_FLAG_PERROR)
643 uci_perror(ctx, NULL);
644 if ((ctx->err != UCI_ERR_PARSE) ||
645 (ctx->flags & UCI_FLAG_STRICT))
646 UCI_THROW(ctx, ctx->err);
649 uci_fixup_section(ctx, ctx->pctx->section);
650 if (!pctx->package && name)
651 uci_switch_config(ctx);
653 *package = pctx->package;
655 pctx->package = NULL;
658 uci_switch_config(ctx);
660 /* no error happened, we can get rid of the parser context now */
667 static char *uci_config_path(struct uci_context *ctx, const char *name)
671 UCI_ASSERT(ctx, uci_validate_package(name));
672 filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
673 sprintf(filename, "%s/%s", ctx->confdir, name);
678 void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
680 struct uci_package *p = *package;
687 p->path = uci_config_path(ctx, p->e.name);
689 UCI_THROW(ctx, UCI_ERR_INVAL);
692 /* open the config file for writing now, so that it is locked */
693 f = uci_open_stream(ctx, p->path, SEEK_SET, true, true);
695 /* flush unsaved changes and reload from delta file */
696 UCI_TRAP_SAVE(ctx, done);
699 name = uci_strdup(ctx, p->e.name);
700 path = uci_strdup(ctx, p->path);
701 /* dump our own changes to the delta file */
702 if (!uci_list_empty(&p->delta))
703 UCI_INTERNAL(uci_save, ctx, p);
706 * other processes might have modified the config
707 * as well. dump and reload
709 uci_free_package(&p);
711 UCI_INTERNAL(uci_import, ctx, f, name, &p, true);
717 /* freed together with the uci_package */
722 if (!uci_load_delta(ctx, p, true))
727 if (ftruncate(fileno(f), 0) < 0)
728 UCI_THROW(ctx, UCI_ERR_IO);
730 uci_export(ctx, f, p, false);
731 UCI_TRAP_RESTORE(ctx);
740 UCI_THROW(ctx, ctx->err);
745 * This function returns the filename by returning the string
746 * after the last '/' character. By checking for a non-'\0'
747 * character afterwards, directories are ignored (glob marks
748 * those with a trailing '/'
750 static inline char *get_filename(char *path)
754 p = strrchr(path, '/');
761 static char **uci_list_config_files(struct uci_context *ctx)
769 dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
770 sprintf(dir, "%s/*", ctx->confdir);
771 if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
773 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
776 size = sizeof(char *) * (globbuf.gl_pathc + 1);
777 for(i = 0; i < globbuf.gl_pathc; i++) {
780 p = get_filename(globbuf.gl_pathv[i]);
784 size += strlen(p) + 1;
787 configs = uci_malloc(ctx, size);
788 buf = (char *) &configs[globbuf.gl_pathc + 1];
789 for(i = 0; i < globbuf.gl_pathc; i++) {
792 p = get_filename(globbuf.gl_pathv[i]);
796 if (!uci_validate_package(p))
801 buf += strlen(buf) + 1;
808 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
810 struct uci_package *package = NULL;
817 /* relative path outside of /etc/config */
819 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
822 /* absolute path outside of /etc/config */
823 filename = uci_strdup(ctx, name);
824 name = strrchr(name, '/') + 1;
828 /* config in /etc/config */
829 filename = uci_config_path(ctx, name);
834 file = uci_open_stream(ctx, filename, SEEK_SET, false, false);
836 UCI_TRAP_SAVE(ctx, done);
837 UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
838 UCI_TRAP_RESTORE(ctx);
841 package->path = filename;
842 package->has_delta = confdir;
843 uci_load_delta(ctx, package, false);
847 uci_close_stream(file);
849 UCI_THROW(ctx, ctx->err);
853 __private UCI_BACKEND(uci_file_backend, "file",
854 .load = uci_file_load,
855 .commit = uci_file_commit,
856 .list_configs = uci_list_config_files,