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: Set an element's value; create the element if necessary
156 * The updated/created element is stored in ptr->last
158 extern int uci_set(struct uci_context *ctx, struct uci_ptr *ptr);
161 * uci_add_list: Append a string to an element list
163 * @ptr: uci pointer (with value)
165 * Note: if the given option already contains a string value,
166 * it will be converted to an 1-element-list before appending the next element
168 extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
171 * uci_rename: Rename an element
173 * @ptr: uci pointer (with value)
175 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
178 * uci_delete: Delete a section or option
182 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
185 * uci_save: save change history for a package
187 * @p: uci_package struct
189 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
192 * uci_commit: commit changes to a package
194 * @p: uci_package struct pointer
195 * @overwrite: overwrite existing config data and flush history
197 * committing may reload the whole uci_package data,
198 * the supplied pointer is updated accordingly
200 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
203 * uci_list_configs: List available uci config files
206 * caller is responsible for freeing the allocated memory behind list
208 extern int uci_list_configs(struct uci_context *ctx, char ***list);
211 * uci_set_savedir: override the default history save directory
213 * @dir: directory name
215 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
218 * uci_set_savedir: override the default config storage directory
220 * @dir: directory name
222 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
225 * uci_add_history_path: add a directory to the search path for change history files
227 * @dir: directory name
229 * This function allows you to add directories, which contain 'overlays'
230 * for the active config, that will never be committed.
232 extern int uci_add_history_path(struct uci_context *ctx, const char *dir);
235 * uci_revert: revert all changes to a config item
239 extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr);
242 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
244 * @stream: input stream
245 * @str: pointer to the current line (use NULL for parsing the next line)
246 * @result: pointer for the result
248 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
251 * uci_set_backend: change the default backend
253 * @name: name of the backend
255 * The default backend is "file", which uses /etc/config for config storage
257 extern int uci_set_backend(struct uci_context *ctx, const char *name);
260 * uci_validate_text: validate a value string for uci options
263 * this function checks whether a given string is acceptable as value
266 extern bool uci_validate_text(const char *str);
268 /* UCI data structures */
271 UCI_TYPE_HISTORY = 1,
272 UCI_TYPE_PACKAGE = 2,
273 UCI_TYPE_SECTION = 3,
276 UCI_TYPE_BACKEND = 6,
280 enum uci_option_type {
286 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
287 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
288 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
289 UCI_FLAG_SAVED_HISTORY = (1 << 3), /* store the saved history in memory as well */
294 struct uci_list list;
301 struct uci_element e;
302 char **(*list_configs)(struct uci_context *ctx);
303 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
304 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
313 /* list of config packages */
314 struct uci_list root;
316 /* parser context, use for error handling only */
317 struct uci_parse_context *pctx;
319 /* backend for import and export */
320 struct uci_backend *backend;
321 struct uci_list backends;
323 /* uci runtime flags */
324 enum uci_flags flags;
329 /* search path for history files */
330 struct uci_list history_path;
336 bool internal, nested;
343 struct uci_element e;
344 struct uci_list sections;
345 struct uci_context *ctx;
350 struct uci_backend *backend;
353 struct uci_list history;
354 struct uci_list saved_history;
359 struct uci_element e;
360 struct uci_list options;
361 struct uci_package *package;
368 struct uci_element e;
369 struct uci_section *section;
370 enum uci_option_type type;
372 struct uci_list list;
387 struct uci_element e;
388 enum uci_command cmd;
395 enum uci_type target;
397 UCI_LOOKUP_DONE = (1 << 0),
398 UCI_LOOKUP_COMPLETE = (1 << 1),
399 UCI_LOOKUP_EXTENDED = (1 << 2),
402 struct uci_package *p;
403 struct uci_section *s;
404 struct uci_option *o;
405 struct uci_element *last;
414 /* linked list handling */
416 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
420 * container_of - cast a member of a structure out to the containing structure
421 * @ptr: the pointer to the member.
422 * @type: the type of the container struct this is embedded in.
423 * @member: the name of the member within the struct.
425 #define container_of(ptr, type, member) \
426 ((type *) ((char *)ptr - offsetof(type,member)))
430 * uci_list_entry: casts an uci_list pointer to the containing struct.
431 * @_type: config, section or option
432 * @_ptr: pointer to the uci_list struct
434 #define list_to_element(ptr) \
435 container_of(ptr, struct uci_element, list)
438 * uci_foreach_entry: loop through a list of uci elements
439 * @_list: pointer to the uci_list struct
440 * @_ptr: iteration variable, struct uci_element
442 * use like a for loop, e.g:
443 * uci_foreach(&list, p) {
447 #define uci_foreach_element(_list, _ptr) \
448 for(_ptr = list_to_element((_list)->next); \
449 &_ptr->list != (_list); \
450 _ptr = list_to_element(_ptr->list.next))
453 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
454 * @_list: pointer to the uci_list struct
455 * @_tmp: temporary variable, struct uci_element *
456 * @_ptr: iteration variable, struct uci_element *
458 * use like a for loop, e.g:
459 * uci_foreach(&list, p) {
463 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
464 for(_ptr = list_to_element((_list)->next), \
465 _tmp = list_to_element(_ptr->list.next); \
466 &_ptr->list != (_list); \
467 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
470 * uci_list_empty: returns true if a list is empty
473 #define uci_list_empty(list) ((list)->next == (list))
475 /* wrappers for dynamic type handling */
476 #define uci_type_backend UCI_TYPE_BACKEND
477 #define uci_type_history UCI_TYPE_HISTORY
478 #define uci_type_package UCI_TYPE_PACKAGE
479 #define uci_type_section UCI_TYPE_SECTION
480 #define uci_type_option UCI_TYPE_OPTION
482 /* element typecasting */
483 #ifdef UCI_DEBUG_TYPECAST
484 static const char *uci_typestr[] = {
485 [uci_type_backend] = "backend",
486 [uci_type_history] = "history",
487 [uci_type_package] = "package",
488 [uci_type_section] = "section",
489 [uci_type_option] = "option",
492 static void uci_typecast_error(int from, int to)
494 fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]);
497 #define BUILD_CAST(_type) \
498 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
500 if (e->type != uci_type_ ## _type) { \
501 uci_typecast_error(e->type, uci_type_ ## _type); \
503 return (struct uci_ ## _type *) e; \
513 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
514 #define uci_to_history(ptr) container_of(ptr, struct uci_history, e)
515 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
516 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
517 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
521 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
523 * @type: {package,section,option}
524 * @name: string containing the name of the element
525 * @datasize: additional buffer size to reserve at the end of the struct
527 #define uci_alloc_element(ctx, type, name, datasize) \
528 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
530 #define uci_dataptr(ptr) \
531 (((char *) ptr) + sizeof(*ptr))