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.
18 #include "uci_config.h"
21 * you can use these defines to enable debugging behavior for
22 * apps compiled against libuci:
24 * #define UCI_DEBUG_TYPECAST:
25 * enable uci_element typecast checking at run time
33 #define UCI_CONFDIR "/etc/config"
34 #define UCI_SAVEDIR "/tmp/.uci"
35 #define UCI_DIRMODE 0700
36 #define UCI_FILEMODE 0600
54 struct uci_list *next;
55 struct uci_list *prev;
66 struct uci_parse_context;
70 * uci_alloc_context: Allocate a new uci context
72 extern struct uci_context *uci_alloc_context(void);
75 * uci_free_context: Free the uci context including all of its data
77 extern void uci_free_context(struct uci_context *ctx);
80 * uci_perror: Print the last uci error that occured
82 * @str: string to print before the error message
84 extern void uci_perror(struct uci_context *ctx, const char *str);
87 * uci_import: Import uci config data from a stream
89 * @stream: file stream to import from
90 * @name: (optional) assume the config has the given name
91 * @package: (optional) store the last parsed config package in this variable
92 * @single: ignore the 'package' keyword and parse everything into a single package
94 * the name parameter is for config files that don't explicitly use the 'package <...>' keyword
95 * if 'package' points to a non-null struct pointer, enable history tracking and merge
97 extern int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single);
100 * uci_export: Export one or all uci config packages
102 * @stream: output stream
103 * @package: (optional) uci config package to export
104 * @header: include the package header
106 extern int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header);
109 * uci_load: Parse an uci config file and store it in the uci context
112 * @name: name of the config file (relative to the config directory)
113 * @package: store the loaded config package in this variable
115 extern int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package);
118 * uci_unload: Unload a config file from the uci context
121 * @package: pointer to the uci_package struct
123 extern int uci_unload(struct uci_context *ctx, struct uci_package *p);
126 * uci_lookup_ptr: Split an uci tuple string and look up an element tree
128 * @ptr: lookup result struct
129 * @str: uci tuple string to look up
130 * @extended: allow extended syntax lookup
132 * if extended is set to true, uci_lookup_ptr supports the following
136 * network.@interface[0].ifname ('ifname' option of the first interface section)
137 * network.@interface[-1] (last interface section)
138 * Note: uci_lookup_ext will automatically load a config package if necessary
140 extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
143 * uci_add_section: Add an unnamed section
145 * @p: package to add the section to
146 * @type: section type
147 * @res: pointer to store a reference to the new section in
149 extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res);
152 * uci_set_element_value: Replace an element's value with a new one
154 * @element: pointer to an uci_element struct pointer
157 * Only valid for uci_option and uci_section. Will replace the type string
158 * when used with an uci_section
160 extern int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, const char *value);
163 * uci_set: Set an element's value; create the element if necessary
165 * @package: package name
166 * @section: section name
167 * @option: option name
168 * @value: value (option) or type (section)
169 * @result: store the updated element in this variable (optional)
171 extern int uci_set(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_element **result);
174 * uci_add_list: Append a string to an element list
176 * @ptr: uci pointer (with value)
178 * Note: if the given option already contains a string value,
179 * it will be converted to an 1-element-list before appending the next element
181 extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
184 * uci_rename: Rename an element
186 * @ptr: uci pointer (with value)
188 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
191 * uci_delete: Delete a section or option
195 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
198 * uci_save: save change history for a package
200 * @p: uci_package struct
202 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
205 * uci_commit: commit changes to a package
207 * @p: uci_package struct pointer
208 * @overwrite: overwrite existing config data and flush history
210 * committing may reload the whole uci_package data,
211 * the supplied pointer is updated accordingly
213 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
216 * uci_list_configs: List available uci config files
219 * caller is responsible for freeing the allocated memory behind list
221 extern int uci_list_configs(struct uci_context *ctx, char ***list);
224 * uci_set_savedir: override the default history save directory
226 * @dir: directory name
228 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
231 * uci_set_savedir: override the default config storage directory
233 * @dir: directory name
235 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
238 * uci_add_history_path: add a directory to the search path for change history files
240 * @dir: directory name
242 * This function allows you to add directories, which contain 'overlays'
243 * for the active config, that will never be committed.
245 extern int uci_add_history_path(struct uci_context *ctx, const char *dir);
248 * uci_revert: revert all changes to a config item
250 * @p: pointer to a uci_package struct ptr (will be replaced by the revert)
251 * @section: section name (optional)
252 * @option option name (optional)
254 extern int uci_revert(struct uci_context *ctx, struct uci_package **p, const char *section, const char *option);
257 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
259 * @stream: input stream
260 * @str: pointer to the current line (use NULL for parsing the next line)
261 * @result: pointer for the result
263 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
266 * uci_set_backend: change the default backend
268 * @name: name of the backend
270 * The default backend is "file", which uses /etc/config for config storage
272 extern int uci_set_backend(struct uci_context *ctx, const char *name);
275 * uci_validate_text: validate a value string for uci options
278 * this function checks whether a given string is acceptable as value
281 extern bool uci_validate_text(const char *str);
283 /* UCI data structures */
286 UCI_TYPE_HISTORY = 1,
287 UCI_TYPE_PACKAGE = 2,
288 UCI_TYPE_SECTION = 3,
291 UCI_TYPE_BACKEND = 6,
295 enum uci_option_type {
301 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
302 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
303 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
304 UCI_FLAG_SAVED_HISTORY = (1 << 3), /* store the saved history in memory as well */
309 struct uci_list list;
316 struct uci_element e;
317 char **(*list_configs)(struct uci_context *ctx);
318 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
319 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
328 /* list of config packages */
329 struct uci_list root;
331 /* parser context, use for error handling only */
332 struct uci_parse_context *pctx;
334 /* backend for import and export */
335 struct uci_backend *backend;
336 struct uci_list backends;
338 /* uci runtime flags */
339 enum uci_flags flags;
344 /* search path for history files */
345 struct uci_list history_path;
351 bool internal, nested;
358 struct uci_element e;
359 struct uci_list sections;
360 struct uci_context *ctx;
365 struct uci_backend *backend;
368 struct uci_list history;
369 struct uci_list saved_history;
374 struct uci_element e;
375 struct uci_list options;
376 struct uci_package *package;
383 struct uci_element e;
384 struct uci_section *section;
385 enum uci_option_type type;
387 struct uci_list list;
402 struct uci_element e;
403 enum uci_command cmd;
410 enum uci_type target;
412 UCI_LOOKUP_DONE = (1 << 0),
413 UCI_LOOKUP_COMPLETE = (1 << 1),
414 UCI_LOOKUP_EXTENDED = (1 << 2),
417 struct uci_package *p;
418 struct uci_section *s;
419 struct uci_option *o;
420 struct uci_element *last;
429 /* linked list handling */
431 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
435 * container_of - cast a member of a structure out to the containing structure
436 * @ptr: the pointer to the member.
437 * @type: the type of the container struct this is embedded in.
438 * @member: the name of the member within the struct.
440 #define container_of(ptr, type, member) \
441 ((type *) ((char *)ptr - offsetof(type,member)))
445 * uci_list_entry: casts an uci_list pointer to the containing struct.
446 * @_type: config, section or option
447 * @_ptr: pointer to the uci_list struct
449 #define list_to_element(ptr) \
450 container_of(ptr, struct uci_element, list)
453 * uci_foreach_entry: loop through a list of uci elements
454 * @_list: pointer to the uci_list struct
455 * @_ptr: iteration variable, struct uci_element
457 * use like a for loop, e.g:
458 * uci_foreach(&list, p) {
462 #define uci_foreach_element(_list, _ptr) \
463 for(_ptr = list_to_element((_list)->next); \
464 &_ptr->list != (_list); \
465 _ptr = list_to_element(_ptr->list.next))
468 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
469 * @_list: pointer to the uci_list struct
470 * @_tmp: temporary variable, struct uci_element *
471 * @_ptr: iteration variable, struct uci_element *
473 * use like a for loop, e.g:
474 * uci_foreach(&list, p) {
478 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
479 for(_ptr = list_to_element((_list)->next), \
480 _tmp = list_to_element(_ptr->list.next); \
481 &_ptr->list != (_list); \
482 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
485 * uci_list_empty: returns true if a list is empty
488 #define uci_list_empty(list) ((list)->next == (list))
490 /* wrappers for dynamic type handling */
491 #define uci_type_backend UCI_TYPE_BACKEND
492 #define uci_type_history UCI_TYPE_HISTORY
493 #define uci_type_package UCI_TYPE_PACKAGE
494 #define uci_type_section UCI_TYPE_SECTION
495 #define uci_type_option UCI_TYPE_OPTION
497 /* element typecasting */
498 #ifdef UCI_DEBUG_TYPECAST
499 static const char *uci_typestr[] = {
500 [uci_type_backend] = "backend",
501 [uci_type_history] = "history",
502 [uci_type_package] = "package",
503 [uci_type_section] = "section",
504 [uci_type_option] = "option",
507 static void uci_typecast_error(int from, int to)
509 fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]);
512 #define BUILD_CAST(_type) \
513 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
515 if (e->type != uci_type_ ## _type) { \
516 uci_typecast_error(e->type, uci_type_ ## _type); \
518 return (struct uci_ ## _type *) e; \
528 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
529 #define uci_to_history(ptr) container_of(ptr, struct uci_history, e)
530 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
531 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
532 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
536 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
538 * @type: {package,section,option}
539 * @name: string containing the name of the element
540 * @datasize: additional buffer size to reserve at the end of the struct
542 #define uci_alloc_element(ctx, type, name, datasize) \
543 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
545 #define uci_dataptr(ptr) \
546 (((char *) ptr) + sizeof(*ptr))