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.
19 * you can use these defines to enable debugging behavior for
20 * apps compiled against libuci:
22 * #define UCI_DEBUG_TYPECAST:
23 * enable uci_element typecast checking at run time
29 #define UCI_DEBUG_TYPECAST
36 #define UCI_CONFDIR "/etc/config"
53 struct uci_list
*next
;
54 struct uci_list
*prev
;
62 struct uci_parse_context
;
66 * uci_alloc_context: Allocate a new uci context
68 extern struct uci_context
*uci_alloc_context(void);
71 * uci_free_context: Free the uci context including all of its data
73 extern void uci_free_context(struct uci_context
*ctx
);
76 * uci_perror: Print the last uci error that occured
78 * @str: string to print before the error message
80 extern void uci_perror(struct uci_context
*ctx
, const char *str
);
83 * uci_import: Import uci config data from a stream
85 * @stream: file stream to import from
86 * @name: (optional) assume the config has the given name
87 * @package: (optional) store the last parsed config package in this variable
88 * @single: ignore the 'package' keyword and parse everything into a single package
90 * the name parameter is for config files that don't explicitly use the 'package <...>' keyword
92 extern int uci_import(struct uci_context
*ctx
, FILE *stream
, const char *name
, struct uci_package
**package
, bool single
);
95 * uci_export: Export one or all uci config packages
97 * @stream: output stream
98 * @package: (optional) uci config package to export
99 * @header: include the package header
101 extern int uci_export(struct uci_context
*ctx
, FILE *stream
, struct uci_package
*package
, bool header
);
104 * uci_load: Parse an uci config file and store it in the uci context
107 * @name: name of the config file (relative to the config directory)
108 * @package: store the loaded config package in this variable
110 extern int uci_load(struct uci_context
*ctx
, const char *name
, struct uci_package
**package
);
113 * uci_unload: Unload a config file from the uci context
116 * @package: pointer to the uci_package struct
118 extern int uci_unload(struct uci_context
*ctx
, struct uci_package
*p
);
121 * uci_cleanup: Clean up after an error
125 extern int uci_cleanup(struct uci_context
*ctx
);
128 * uci_lookup: Look up an uci element
131 * @res: where to store the result
132 * @package: uci_package struct
133 * @section: config section (optional)
134 * @option: option to search for (optional)
136 * If section is omitted, then a pointer to the config package is returned
137 * If option is omitted, then a pointer to the config section is returned
139 extern int uci_lookup(struct uci_context
*ctx
, struct uci_element
**res
, struct uci_package
*package
, char *section
, char *option
);
142 * uci_set_element_value: Replace an element's value with a new one
144 * @element: pointer to an uci_element struct pointer
147 * Only valid for uci_option and uci_section. Will replace the type string
148 * when used with an uci_section
150 extern int uci_set_element_value(struct uci_context
*ctx
, struct uci_element
**element
, char *value
);
153 * uci_set: Set an element's value; create the element if necessary
155 * @package: package name
156 * @section: section name
157 * @option: option name
158 * @value: value (option) or type (section)
160 extern int uci_set(struct uci_context
*ctx
, char *package
, char *section
, char *option
, char *value
);
163 * uci_commit: commit changes to a package
165 * @p: uci_package struct
167 extern int uci_commit(struct uci_context
*ctx
, struct uci_package
*p
);
170 * uci_list_configs: List available uci config files
174 extern char **uci_list_configs(struct uci_context
*ctx
);
176 /* UCI data structures */
178 UCI_TYPE_PACKAGE
= 0,
179 UCI_TYPE_SECTION
= 1,
185 struct uci_list list
;
192 /* list of config packages */
193 struct uci_list root
;
195 /* parser context, use for error handling only */
196 struct uci_parse_context
*pctx
;
206 struct uci_parse_context
214 struct uci_package
*package
;
215 struct uci_section
*section
;
224 struct uci_element e
;
225 struct uci_list sections
;
226 struct uci_context
*ctx
;
232 struct uci_list history
;
237 struct uci_element e
;
238 struct uci_list options
;
239 struct uci_package
*package
;
245 struct uci_element e
;
246 struct uci_section
*section
;
258 struct uci_list list
;
259 enum uci_command cmd
;
265 /* linked list handling */
267 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
271 * container_of - cast a member of a structure out to the containing structure
272 * @ptr: the pointer to the member.
273 * @type: the type of the container struct this is embedded in.
274 * @member: the name of the member within the struct.
276 #define container_of(ptr, type, member) \
277 ((type *) ((char *)ptr - offsetof(type,member)))
281 * uci_list_entry: casts an uci_list pointer to the containing struct.
282 * @_type: config, section or option
283 * @_ptr: pointer to the uci_list struct
285 #define element_to(type, ptr) \
286 container_of(ptr, struct uci_ ## type, e)
288 #define list_to_element(ptr) \
289 container_of(ptr, struct uci_element, list)
292 * uci_foreach_entry: loop through a list of uci elements
293 * @_list: pointer to the uci_list struct
294 * @_ptr: iteration variable, struct uci_element
296 * use like a for loop, e.g:
297 * uci_foreach(&list, p) {
301 #define uci_foreach_element(_list, _ptr) \
302 for(_ptr = list_to_element((_list)->next); \
303 &_ptr->list != (_list); \
304 _ptr = list_to_element(_ptr->list.next))
307 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
308 * @_list: pointer to the uci_list struct
309 * @_tmp: temporary variable, struct uci_element *
310 * @_ptr: iteration variable, struct uci_element *
312 * use like a for loop, e.g:
313 * uci_foreach(&list, p) {
317 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
318 for(_ptr = list_to_element((_list)->next), \
319 _tmp = list_to_element(_ptr->list.next); \
320 &_ptr->list != (_list); \
321 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
324 * uci_list_empty: returns true if a list is empty
327 #define uci_list_empty(list) ((list)->next == (list))
329 /* wrappers for dynamic type handling */
330 #define uci_type_package UCI_TYPE_PACKAGE
331 #define uci_type_section UCI_TYPE_SECTION
332 #define uci_type_option UCI_TYPE_OPTION
334 /* element typecasting */
335 #ifdef UCI_DEBUG_TYPECAST
336 static const char *uci_typestr
[] = {
337 [uci_type_package
] = "package",
338 [uci_type_section
] = "section",
339 [uci_type_option
] = "option"
342 static void uci_typecast_error(int from
, int to
)
344 fprintf(stderr
, "Invalid typecast from '%s' to '%s'\n", uci_typestr
[from
], uci_typestr
[to
]);
347 #define BUILD_CAST(_type) \
348 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
350 if (e->type != uci_type_ ## _type) { \
351 uci_typecast_error(e->type, uci_type_ ## _type); \
353 return (struct uci_ ## _type *) e; \
361 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
362 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
363 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
367 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
369 * @type: {package,section,option}
370 * @name: string containing the name of the element
371 * @datasize: additional buffer size to reserve at the end of the struct
373 #define uci_alloc_element(ctx, type, name, datasize) \
374 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
376 #define uci_dataptr(ptr) \
377 (((char *) ptr) + sizeof(*ptr))