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_geterror: Get an error string for the last uci error
89 * @dest: target pointer for the string
90 * @str: prefix for the error message
92 * Note: string must be freed by the caller
94 extern void uci_get_errorstr(struct uci_context *ctx, char **dest, const char *str);
97 * uci_import: Import uci config data from a stream
99 * @stream: file stream to import from
100 * @name: (optional) assume the config has the given name
101 * @package: (optional) store the last parsed config package in this variable
102 * @single: ignore the 'package' keyword and parse everything into a single package
104 * the name parameter is for config files that don't explicitly use the 'package <...>' keyword
105 * if 'package' points to a non-null struct pointer, enable history tracking and merge
107 extern int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single);
110 * uci_export: Export one or all uci config packages
112 * @stream: output stream
113 * @package: (optional) uci config package to export
114 * @header: include the package header
116 extern int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header);
119 * uci_load: Parse an uci config file and store it in the uci context
122 * @name: name of the config file (relative to the config directory)
123 * @package: store the loaded config package in this variable
125 extern int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package);
128 * uci_unload: Unload a config file from the uci context
131 * @package: pointer to the uci_package struct
133 extern int uci_unload(struct uci_context *ctx, struct uci_package *p);
136 * uci_lookup_ptr: Split an uci tuple string and look up an element tree
138 * @ptr: lookup result struct
139 * @str: uci tuple string to look up
140 * @extended: allow extended syntax lookup
142 * if extended is set to true, uci_lookup_ptr supports the following
146 * network.@interface[0].ifname ('ifname' option of the first interface section)
147 * network.@interface[-1] (last interface section)
148 * Note: uci_lookup_ext will automatically load a config package if necessary
150 extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
153 * uci_add_section: Add an unnamed section
155 * @p: package to add the section to
156 * @type: section type
157 * @res: pointer to store a reference to the new section in
159 extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res);
162 * uci_set: Set an element's value; create the element if necessary
166 * The updated/created element is stored in ptr->last
168 extern int uci_set(struct uci_context *ctx, struct uci_ptr *ptr);
171 * uci_add_list: Append a string to an element list
173 * @ptr: uci pointer (with value)
175 * Note: if the given option already contains a string value,
176 * it will be converted to an 1-element-list before appending the next element
178 extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
181 * uci_reorder: Reposition a section
183 * @s: uci section to reposition
184 * @pos: new position in the section list
186 extern int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos);
189 * uci_rename: Rename an element
191 * @ptr: uci pointer (with value)
193 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
196 * uci_delete: Delete a section or option
200 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
203 * uci_save: save change history for a package
205 * @p: uci_package struct
207 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
210 * uci_commit: commit changes to a package
212 * @p: uci_package struct pointer
213 * @overwrite: overwrite existing config data and flush history
215 * committing may reload the whole uci_package data,
216 * the supplied pointer is updated accordingly
218 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
221 * uci_list_configs: List available uci config files
224 * caller is responsible for freeing the allocated memory behind list
226 extern int uci_list_configs(struct uci_context *ctx, char ***list);
229 * uci_set_savedir: override the default history save directory
231 * @dir: directory name
233 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
236 * uci_set_savedir: override the default config storage directory
238 * @dir: directory name
240 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
243 * uci_add_history_path: add a directory to the search path for change history files
245 * @dir: directory name
247 * This function allows you to add directories, which contain 'overlays'
248 * for the active config, that will never be committed.
250 extern int uci_add_history_path(struct uci_context *ctx, const char *dir);
253 * uci_revert: revert all changes to a config item
257 extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr);
260 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
262 * @stream: input stream
263 * @str: pointer to the current line (use NULL for parsing the next line)
264 * @result: pointer for the result
266 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
269 * uci_set_backend: change the default backend
271 * @name: name of the backend
273 * The default backend is "file", which uses /etc/config for config storage
275 extern int uci_set_backend(struct uci_context *ctx, const char *name);
278 * uci_validate_text: validate a value string for uci options
281 * this function checks whether a given string is acceptable as value
284 extern bool uci_validate_text(const char *str);
286 /* UCI data structures */
289 UCI_TYPE_HISTORY = 1,
290 UCI_TYPE_PACKAGE = 2,
291 UCI_TYPE_SECTION = 3,
294 UCI_TYPE_BACKEND = 6,
298 enum uci_option_type {
304 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
305 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
306 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
307 UCI_FLAG_SAVED_HISTORY = (1 << 3), /* store the saved history in memory as well */
312 struct uci_list list;
319 struct uci_element e;
320 char **(*list_configs)(struct uci_context *ctx);
321 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
322 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
331 /* list of config packages */
332 struct uci_list root;
334 /* parser context, use for error handling only */
335 struct uci_parse_context *pctx;
337 /* backend for import and export */
338 struct uci_backend *backend;
339 struct uci_list backends;
341 /* uci runtime flags */
342 enum uci_flags flags;
347 /* search path for history files */
348 struct uci_list history_path;
354 bool internal, nested;
361 struct uci_element e;
362 struct uci_list sections;
363 struct uci_context *ctx;
368 struct uci_backend *backend;
371 struct uci_list history;
372 struct uci_list saved_history;
377 struct uci_element e;
378 struct uci_list options;
379 struct uci_package *package;
386 struct uci_element e;
387 struct uci_section *section;
388 enum uci_option_type type;
390 struct uci_list list;
406 struct uci_element e;
407 enum uci_command cmd;
414 enum uci_type target;
416 UCI_LOOKUP_DONE = (1 << 0),
417 UCI_LOOKUP_COMPLETE = (1 << 1),
418 UCI_LOOKUP_EXTENDED = (1 << 2),
421 struct uci_package *p;
422 struct uci_section *s;
423 struct uci_option *o;
424 struct uci_element *last;
433 /* linked list handling */
435 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
439 * container_of - cast a member of a structure out to the containing structure
440 * @ptr: the pointer to the member.
441 * @type: the type of the container struct this is embedded in.
442 * @member: the name of the member within the struct.
445 #define container_of(ptr, type, member) \
446 ((type *) ((char *)ptr - offsetof(type,member)))
451 * uci_list_entry: casts an uci_list pointer to the containing struct.
452 * @_type: config, section or option
453 * @_ptr: pointer to the uci_list struct
455 #define list_to_element(ptr) \
456 container_of(ptr, struct uci_element, list)
459 * uci_foreach_entry: loop through a list of uci elements
460 * @_list: pointer to the uci_list struct
461 * @_ptr: iteration variable, struct uci_element
463 * use like a for loop, e.g:
464 * uci_foreach(&list, p) {
468 #define uci_foreach_element(_list, _ptr) \
469 for(_ptr = list_to_element((_list)->next); \
470 &_ptr->list != (_list); \
471 _ptr = list_to_element(_ptr->list.next))
474 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
475 * @_list: pointer to the uci_list struct
476 * @_tmp: temporary variable, struct uci_element *
477 * @_ptr: iteration variable, struct uci_element *
479 * use like a for loop, e.g:
480 * uci_foreach(&list, p) {
484 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
485 for(_ptr = list_to_element((_list)->next), \
486 _tmp = list_to_element(_ptr->list.next); \
487 &_ptr->list != (_list); \
488 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
491 * uci_list_empty: returns true if a list is empty
494 #define uci_list_empty(list) ((list)->next == (list))
496 /* wrappers for dynamic type handling */
497 #define uci_type_backend UCI_TYPE_BACKEND
498 #define uci_type_history UCI_TYPE_HISTORY
499 #define uci_type_package UCI_TYPE_PACKAGE
500 #define uci_type_section UCI_TYPE_SECTION
501 #define uci_type_option UCI_TYPE_OPTION
503 /* element typecasting */
504 #ifdef UCI_DEBUG_TYPECAST
505 static const char *uci_typestr[] = {
506 [uci_type_backend] = "backend",
507 [uci_type_history] = "history",
508 [uci_type_package] = "package",
509 [uci_type_section] = "section",
510 [uci_type_option] = "option",
513 static void uci_typecast_error(int from, int to)
515 fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]);
518 #define BUILD_CAST(_type) \
519 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
521 if (e->type != uci_type_ ## _type) { \
522 uci_typecast_error(e->type, uci_type_ ## _type); \
524 return (struct uci_ ## _type *) e; \
534 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
535 #define uci_to_history(ptr) container_of(ptr, struct uci_history, e)
536 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
537 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
538 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
542 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
544 * @type: {package,section,option}
545 * @name: string containing the name of the element
546 * @datasize: additional buffer size to reserve at the end of the struct
548 #define uci_alloc_element(ctx, type, name, datasize) \
549 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
551 #define uci_dataptr(ptr) \
552 (((char *) ptr) + sizeof(*ptr))