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.
22 #include "uci_config.h"
25 * you can use these defines to enable debugging behavior for
26 * apps compiled against libuci:
28 * #define UCI_DEBUG_TYPECAST:
29 * enable uci_element typecast checking at run time
38 #define UCI_CONFDIR "/etc/config"
39 #define UCI_SAVEDIR "/tmp/.uci"
40 #define UCI_DIRMODE 0700
41 #define UCI_FILEMODE 0600
59 struct uci_list *next;
60 struct uci_list *prev;
73 struct uci_parse_option;
74 struct uci_parse_context;
78 * uci_alloc_context: Allocate a new uci context
80 extern struct uci_context *uci_alloc_context(void);
83 * uci_free_context: Free the uci context including all of its data
85 extern void uci_free_context(struct uci_context *ctx);
88 * uci_perror: Print the last uci error that occured
90 * @str: string to print before the error message
92 extern void uci_perror(struct uci_context *ctx, const char *str);
95 * uci_geterror: Get an error string for the last uci error
97 * @dest: target pointer for the string
98 * @str: prefix for the error message
100 * Note: string must be freed by the caller
102 extern void uci_get_errorstr(struct uci_context *ctx, char **dest, const char *str);
105 * uci_import: Import uci config data from a stream
107 * @stream: file stream to import from
108 * @name: (optional) assume the config has the given name
109 * @package: (optional) store the last parsed config package in this variable
110 * @single: ignore the 'package' keyword and parse everything into a single package
112 * the name parameter is for config files that don't explicitly use the 'package <...>' keyword
113 * if 'package' points to a non-null struct pointer, enable delta tracking and merge
115 extern int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single);
118 * uci_export: Export one or all uci config packages
120 * @stream: output stream
121 * @package: (optional) uci config package to export
122 * @header: include the package header
124 extern int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header);
127 * uci_load: Parse an uci config file and store it in the uci context
130 * @name: name of the config file (relative to the config directory)
131 * @package: store the loaded config package in this variable
133 extern int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package);
136 * uci_unload: Unload a config file from the uci context
139 * @package: pointer to the uci_package struct
141 extern int uci_unload(struct uci_context *ctx, struct uci_package *p);
144 * uci_lookup_ptr: Split an uci tuple string and look up an element tree
146 * @ptr: lookup result struct
147 * @str: uci tuple string to look up
148 * @extended: allow extended syntax lookup
150 * if extended is set to true, uci_lookup_ptr supports the following
154 * network.@interface[0].ifname ('ifname' option of the first interface section)
155 * network.@interface[-1] (last interface section)
156 * Note: uci_lookup_ptr will automatically load a config package if necessary
157 * @str must not be constant, as it will be modified and used for the strings inside @ptr,
158 * thus it must also be available as long as @ptr is in use.
160 extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
163 * uci_add_section: Add an unnamed section
165 * @p: package to add the section to
166 * @type: section type
167 * @res: pointer to store a reference to the new section in
169 extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res);
172 * uci_set: Set an element's value; create the element if necessary
176 * The updated/created element is stored in ptr->last
178 extern int uci_set(struct uci_context *ctx, struct uci_ptr *ptr);
181 * uci_add_list: Append a string to an element list
183 * @ptr: uci pointer (with value)
185 * Note: if the given option already contains a string value,
186 * it will be converted to an 1-element-list before appending the next element
188 extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
191 * uci_reorder: Reposition a section
193 * @s: uci section to reposition
194 * @pos: new position in the section list
196 extern int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos);
199 * uci_rename: Rename an element
201 * @ptr: uci pointer (with value)
203 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
206 * uci_delete: Delete a section or option
210 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
213 * uci_save: save change delta for a package
215 * @p: uci_package struct
217 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
220 * uci_commit: commit changes to a package
222 * @p: uci_package struct pointer
223 * @overwrite: overwrite existing config data and flush delta
225 * committing may reload the whole uci_package data,
226 * the supplied pointer is updated accordingly
228 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
231 * uci_list_configs: List available uci config files
234 * caller is responsible for freeing the allocated memory behind list
236 extern int uci_list_configs(struct uci_context *ctx, char ***list);
239 * uci_set_savedir: override the default delta save directory
241 * @dir: directory name
243 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
246 * uci_set_savedir: override the default config storage directory
248 * @dir: directory name
250 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
253 * uci_add_delta_path: add a directory to the search path for change delta files
255 * @dir: directory name
257 * This function allows you to add directories, which contain 'overlays'
258 * for the active config, that will never be committed.
260 extern int uci_add_delta_path(struct uci_context *ctx, const char *dir);
263 * uci_revert: revert all changes to a config item
267 extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr);
270 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
272 * @stream: input stream
273 * @str: pointer to the current line (use NULL for parsing the next line)
274 * @result: pointer for the result
276 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
279 * uci_set_backend: change the default backend
281 * @name: name of the backend
283 * The default backend is "file", which uses /etc/config for config storage
285 extern int uci_set_backend(struct uci_context *ctx, const char *name);
288 * uci_validate_text: validate a value string for uci options
291 * this function checks whether a given string is acceptable as value
294 extern bool uci_validate_text(const char *str);
298 * uci_add_hook: add a uci hook
302 * NB: allocated and freed by the caller
304 extern int uci_add_hook(struct uci_context *ctx, const struct uci_hook_ops *ops);
307 * uci_remove_hook: remove a uci hook
311 extern int uci_remove_hook(struct uci_context *ctx, const struct uci_hook_ops *ops);
314 * uci_load_plugin: load an uci plugin
316 * @filename: path to the uci plugin
318 * NB: plugin will be unloaded automatically when the context is freed
320 int uci_load_plugin(struct uci_context *ctx, const char *filename);
323 * uci_load_plugins: load all uci plugins from a directory
325 * @pattern: pattern of uci plugin files (optional)
327 * if pattern is NULL, then uci_load_plugins will call uci_load_plugin
328 * for uci_*.so in <prefix>/lib/
330 int uci_load_plugins(struct uci_context *ctx, const char *pattern);
333 * uci_parse_ptr: parse a uci string into a uci_ptr
335 * @ptr: target data structure
336 * @str: string to parse
338 * str is modified by this function
340 int uci_parse_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str);
343 * uci_lookup_next: lookup a child element
345 * @e: target element pointer
346 * @list: list of elements
347 * @name: name of the child element
349 * if parent is NULL, the function looks up the package with the given name
351 int uci_lookup_next(struct uci_context *ctx, struct uci_element **e, struct uci_list *list, const char *name);
354 * uci_parse_section: look up a set of options
356 * @opts: list of options to look up
357 * @n_opts: number of options to look up
358 * @tb: array of pointers to found options
360 void uci_parse_section(struct uci_section *s, const struct uci_parse_option *opts,
361 int n_opts, struct uci_option **tb);
364 * uci_hash_options: build a hash over a list of options
365 * @tb: list of option pointers
366 * @n_opts: number of options
368 uint32_t uci_hash_options(struct uci_option **tb, int n_opts);
371 /* UCI data structures */
375 UCI_TYPE_PACKAGE = 2,
376 UCI_TYPE_SECTION = 3,
379 UCI_TYPE_BACKEND = 6,
385 enum uci_option_type {
391 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
392 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
393 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
394 UCI_FLAG_SAVED_DELTA = (1 << 3), /* store the saved delta in memory as well */
399 struct uci_list list;
406 struct uci_element e;
407 char **(*list_configs)(struct uci_context *ctx);
408 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
409 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
418 /* list of config packages */
419 struct uci_list root;
421 /* parser context, use for error handling only */
422 struct uci_parse_context *pctx;
424 /* backend for import and export */
425 struct uci_backend *backend;
426 struct uci_list backends;
428 /* uci runtime flags */
429 enum uci_flags flags;
434 /* search path for delta files */
435 struct uci_list delta_path;
441 bool internal, nested;
445 struct uci_list hooks;
446 struct uci_list plugins;
451 struct uci_element e;
452 struct uci_list sections;
453 struct uci_context *ctx;
458 struct uci_backend *backend;
461 struct uci_list delta;
462 struct uci_list saved_delta;
467 struct uci_element e;
468 struct uci_list options;
469 struct uci_package *package;
476 struct uci_element e;
477 struct uci_section *section;
478 enum uci_option_type type;
480 struct uci_list list;
496 struct uci_element e;
497 enum uci_command cmd;
504 enum uci_type target;
506 UCI_LOOKUP_DONE = (1 << 0),
507 UCI_LOOKUP_COMPLETE = (1 << 1),
508 UCI_LOOKUP_EXTENDED = (1 << 2),
511 struct uci_package *p;
512 struct uci_section *s;
513 struct uci_option *o;
514 struct uci_element *last;
524 void (*load)(const struct uci_hook_ops *ops, struct uci_package *p);
525 void (*set)(const struct uci_hook_ops *ops, struct uci_package *p, struct uci_delta *e);
530 struct uci_element e;
531 const struct uci_hook_ops *ops;
534 struct uci_plugin_ops
536 int (*attach)(struct uci_context *ctx);
537 void (*detach)(struct uci_context *ctx);
542 struct uci_element e;
543 const struct uci_plugin_ops *ops;
547 struct uci_parse_option {
549 enum uci_option_type type;
553 /* linked list handling */
555 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
559 * container_of - cast a member of a structure out to the containing structure
560 * @ptr: the pointer to the member.
561 * @type: the type of the container struct this is embedded in.
562 * @member: the name of the member within the struct.
565 #define container_of(ptr, type, member) \
566 ((type *) ((char *)ptr - offsetof(type,member)))
571 * uci_list_entry: casts an uci_list pointer to the containing struct.
572 * @_type: config, section or option
573 * @_ptr: pointer to the uci_list struct
575 #define list_to_element(ptr) \
576 container_of(ptr, struct uci_element, list)
579 * uci_foreach_entry: loop through a list of uci elements
580 * @_list: pointer to the uci_list struct
581 * @_ptr: iteration variable, struct uci_element
583 * use like a for loop, e.g:
584 * uci_foreach(&list, p) {
588 #define uci_foreach_element(_list, _ptr) \
589 for(_ptr = list_to_element((_list)->next); \
590 &_ptr->list != (_list); \
591 _ptr = list_to_element(_ptr->list.next))
594 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
595 * @_list: pointer to the uci_list struct
596 * @_tmp: temporary variable, struct uci_element *
597 * @_ptr: iteration variable, struct uci_element *
599 * use like a for loop, e.g:
600 * uci_foreach(&list, p) {
604 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
605 for(_ptr = list_to_element((_list)->next), \
606 _tmp = list_to_element(_ptr->list.next); \
607 &_ptr->list != (_list); \
608 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
611 * uci_list_empty: returns true if a list is empty
614 #define uci_list_empty(list) ((list)->next == (list))
616 /* wrappers for dynamic type handling */
617 #define uci_type_backend UCI_TYPE_BACKEND
618 #define uci_type_delta UCI_TYPE_DELTA
619 #define uci_type_package UCI_TYPE_PACKAGE
620 #define uci_type_section UCI_TYPE_SECTION
621 #define uci_type_option UCI_TYPE_OPTION
622 #define uci_type_hook UCI_TYPE_HOOK
623 #define uci_type_plugin UCI_TYPE_PLUGIN
625 /* element typecasting */
626 #ifdef UCI_DEBUG_TYPECAST
627 static const char *uci_typestr[] = {
628 [uci_type_backend] = "backend",
629 [uci_type_delta] = "delta",
630 [uci_type_package] = "package",
631 [uci_type_section] = "section",
632 [uci_type_option] = "option",
633 [uci_type_hook] = "hook",
634 [uci_type_plugin] = "plugin",
637 static void uci_typecast_error(int from, int to)
639 fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]);
642 #define BUILD_CAST(_type) \
643 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
645 if (e->type != uci_type_ ## _type) { \
646 uci_typecast_error(e->type, uci_type_ ## _type); \
648 return (struct uci_ ## _type *) e; \
660 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
661 #define uci_to_delta(ptr) container_of(ptr, struct uci_delta, e)
662 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
663 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
664 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
665 #define uci_to_hook(ptr) container_of(ptr, struct uci_hook, e)
666 #define uci_to_plugin(ptr) container_of(ptr, struct uci_plugin, e)
670 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
672 * @type: {package,section,option}
673 * @name: string containing the name of the element
674 * @datasize: additional buffer size to reserve at the end of the struct
676 #define uci_alloc_element(ctx, type, name, datasize) \
677 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
679 #define uci_dataptr(ptr) \
680 (((char *) ptr) + sizeof(*ptr))
683 * uci_lookup_package: look up a package
685 * @name: name of the package
687 static inline struct uci_package *
688 uci_lookup_package(struct uci_context *ctx, const char *name)
690 struct uci_element *e = NULL;
691 if (uci_lookup_next(ctx, &e, &ctx->root, name) == 0)
692 return uci_to_package(e);
698 * uci_lookup_section: look up a section
700 * @p: package that the section belongs to
701 * @name: name of the section
703 static inline struct uci_section *
704 uci_lookup_section(struct uci_context *ctx, struct uci_package *p, const char *name)
706 struct uci_element *e = NULL;
707 if (uci_lookup_next(ctx, &e, &p->sections, name) == 0)
708 return uci_to_section(e);
714 * uci_lookup_option: look up an option
716 * @section: section that the option belongs to
717 * @name: name of the option
719 static inline struct uci_option *
720 uci_lookup_option(struct uci_context *ctx, struct uci_section *s, const char *name)
722 struct uci_element *e = NULL;
723 if (uci_lookup_next(ctx, &e, &s->options, name) == 0)
724 return uci_to_option(e);
729 static inline const char *
730 uci_lookup_option_string(struct uci_context *ctx, struct uci_section *s, const char *name)
732 struct uci_option *o;
734 o = uci_lookup_option(ctx, s, name);
735 if (!o || o->type != UCI_TYPE_STRING)