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
;
65 struct uci_parse_context
;
69 * uci_parse_tuple: Parse an uci tuple
72 * @package: output package pointer
73 * @section: output section pointer
74 * @option: output option pointer
75 * @value: output value pointer
77 * format: <package>[.<section>[.<option>]][=<value>]
79 extern int uci_parse_tuple(struct uci_context
*ctx
, char *str
, char **package
, char **section
, char **option
, char **value
);
82 * uci_alloc_context: Allocate a new uci context
84 extern struct uci_context
*uci_alloc_context(void);
87 * uci_free_context: Free the uci context including all of its data
89 extern void uci_free_context(struct uci_context
*ctx
);
92 * uci_perror: Print the last uci error that occured
94 * @str: string to print before the error message
96 extern void uci_perror(struct uci_context
*ctx
, const char *str
);
99 * uci_import: Import uci config data from a stream
101 * @stream: file stream to import from
102 * @name: (optional) assume the config has the given name
103 * @package: (optional) store the last parsed config package in this variable
104 * @single: ignore the 'package' keyword and parse everything into a single package
106 * the name parameter is for config files that don't explicitly use the 'package <...>' keyword
107 * if 'package' points to a non-null struct pointer, enable history tracking and merge
109 extern int uci_import(struct uci_context
*ctx
, FILE *stream
, const char *name
, struct uci_package
**package
, bool single
);
112 * uci_export: Export one or all uci config packages
114 * @stream: output stream
115 * @package: (optional) uci config package to export
116 * @header: include the package header
118 extern int uci_export(struct uci_context
*ctx
, FILE *stream
, struct uci_package
*package
, bool header
);
121 * uci_load: Parse an uci config file and store it in the uci context
124 * @name: name of the config file (relative to the config directory)
125 * @package: store the loaded config package in this variable
127 extern int uci_load(struct uci_context
*ctx
, const char *name
, struct uci_package
**package
);
130 * uci_unload: Unload a config file from the uci context
133 * @package: pointer to the uci_package struct
135 extern int uci_unload(struct uci_context
*ctx
, struct uci_package
*p
);
138 * uci_lookup: Look up an uci element
141 * @res: where to store the result
142 * @package: uci_package struct
143 * @section: config section (optional)
144 * @option: option to search for (optional)
146 * If section is omitted, then a pointer to the config package is returned
147 * If option is omitted, then a pointer to the config section is returned
149 extern int uci_lookup(struct uci_context
*ctx
, struct uci_element
**res
, struct uci_package
*package
, const char *section
, const char *option
);
152 * uci_lookup_ext: Extended lookup for an uci element
155 * @res: where to store the result
156 * @ptr: uci pointer tuple
158 * Looks up an element using the extended syntax, which is a superset of what
159 * uci_parse_tuple accepts. It can look up sections by an index with an optional
163 * network.@interface[0].ifname ('ifname' option of the first interface section)
164 * network.@interface[-1] (last interface section)
165 * Note: uci_lookup_ext will automatically load a config package if necessary
167 extern int uci_lookup_ext(struct uci_context
*ctx
, struct uci_element
**res
, char *ptr
);
170 * uci_add_section: Add an unnamed section
172 * @p: package to add the section to
173 * @type: section type
174 * @res: pointer to store a reference to the new section in
176 extern int uci_add_section(struct uci_context
*ctx
, struct uci_package
*p
, const char *type
, struct uci_section
**res
);
179 * uci_set_element_value: Replace an element's value with a new one
181 * @element: pointer to an uci_element struct pointer
184 * Only valid for uci_option and uci_section. Will replace the type string
185 * when used with an uci_section
187 extern int uci_set_element_value(struct uci_context
*ctx
, struct uci_element
**element
, const char *value
);
190 * uci_add_element_list: Append a string to a list option
192 * @option: pointer to the uci option element
193 * @value: string to append
195 extern int uci_add_element_list(struct uci_context
*ctx
, struct uci_option
*o
, const char *value
);
198 * uci_set: Set an element's value; create the element if necessary
200 * @package: package name
201 * @section: section name
202 * @option: option name
203 * @value: value (option) or type (section)
204 * @result: store the updated element in this variable (optional)
206 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
);
209 * uci_add_list: Append a string to an element list
211 * @package: package name
212 * @section: section name
213 * @option: option name
214 * @value: string value
215 * @result: store the updated element in this variable (optional)
217 * Note: if the given option already contains a string, convert it to an 1-element-list
218 * before appending the next element
220 extern int uci_add_list(struct uci_context
*ctx
, struct uci_package
*p
, const char *section
, const char *option
, const char *value
, struct uci_option
**result
);
223 * uci_rename: Rename an element
225 * @package: package name
226 * @section: section name
227 * @option: option name
230 extern int uci_rename(struct uci_context
*ctx
, struct uci_package
*p
, char *section
, char *option
, char *name
);
233 * uci_delete_element: Delete a section or option
235 * @e: element (section or option)
237 extern int uci_delete_element(struct uci_context
*ctx
, struct uci_element
*e
);
240 * uci_delete: Delete a section or option
243 * @section: section name
244 * @option: option name (optional)
246 extern int uci_delete(struct uci_context
*ctx
, struct uci_package
*p
, const char *section
, const char *option
);
249 * uci_save: save change history for a package
251 * @p: uci_package struct
253 extern int uci_save(struct uci_context
*ctx
, struct uci_package
*p
);
256 * uci_commit: commit changes to a package
258 * @p: uci_package struct pointer
259 * @overwrite: overwrite existing config data and flush history
261 * committing may reload the whole uci_package data,
262 * the supplied pointer is updated accordingly
264 extern int uci_commit(struct uci_context
*ctx
, struct uci_package
**p
, bool overwrite
);
267 * uci_list_configs: List available uci config files
270 * caller is responsible for freeing the allocated memory behind list
272 extern int uci_list_configs(struct uci_context
*ctx
, char ***list
);
275 * uci_set_savedir: override the default history save directory
277 * @dir: directory name
279 extern int uci_set_savedir(struct uci_context
*ctx
, const char *dir
);
282 * uci_set_savedir: override the default config storage directory
284 * @dir: directory name
286 extern int uci_set_confdir(struct uci_context
*ctx
, const char *dir
);
289 * uci_add_history_path: add a directory to the search path for change history files
291 * @dir: directory name
293 * This function allows you to add directories, which contain 'overlays'
294 * for the active config, that will never be committed.
296 extern int uci_add_history_path(struct uci_context
*ctx
, const char *dir
);
299 * uci_revert: revert all changes to a config item
301 * @p: pointer to a uci_package struct ptr (will be replaced by the revert)
302 * @section: section name (optional)
303 * @option option name (optional)
305 extern int uci_revert(struct uci_context
*ctx
, struct uci_package
**p
, const char *section
, const char *option
);
308 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
310 * @stream: input stream
311 * @str: pointer to the current line (use NULL for parsing the next line)
312 * @result: pointer for the result
314 extern int uci_parse_argument(struct uci_context
*ctx
, FILE *stream
, char **str
, char **result
);
317 * uci_set_backend: change the default backend
319 * @name: name of the backend
321 * The default backend is "file", which uses /etc/config for config storage
323 extern int uci_set_backend(struct uci_context
*ctx
, const char *name
);
326 * uci_validate_text: validate a value string for uci options
329 * this function checks whether a given string is acceptable as value
332 extern bool uci_validate_text(const char *str
);
334 /* UCI data structures */
336 UCI_TYPE_HISTORY
= 0,
337 UCI_TYPE_PACKAGE
= 1,
338 UCI_TYPE_SECTION
= 2,
341 UCI_TYPE_BACKEND
= 5,
345 enum uci_option_type
{
351 UCI_FLAG_STRICT
= (1 << 0), /* strict mode for the parser */
352 UCI_FLAG_PERROR
= (1 << 1), /* print parser error messages */
353 UCI_FLAG_EXPORT_NAME
= (1 << 2), /* when exporting, name unnamed sections */
354 UCI_FLAG_SAVED_HISTORY
= (1 << 3), /* store the saved history in memory as well */
359 struct uci_list list
;
366 struct uci_element e
;
367 char **(*list_configs
)(struct uci_context
*ctx
);
368 struct uci_package
*(*load
)(struct uci_context
*ctx
, const char *name
);
369 void (*commit
)(struct uci_context
*ctx
, struct uci_package
**p
, bool overwrite
);
378 /* list of config packages */
379 struct uci_list root
;
381 /* parser context, use for error handling only */
382 struct uci_parse_context
*pctx
;
384 /* backend for import and export */
385 struct uci_backend
*backend
;
386 struct uci_list backends
;
388 /* uci runtime flags */
389 enum uci_flags flags
;
394 /* search path for history files */
395 struct uci_list history_path
;
408 struct uci_element e
;
409 struct uci_list sections
;
410 struct uci_context
*ctx
;
415 struct uci_backend
*backend
;
418 struct uci_list history
;
419 struct uci_list saved_history
;
424 struct uci_element e
;
425 struct uci_list options
;
426 struct uci_package
*package
;
433 struct uci_element e
;
434 struct uci_section
*section
;
435 enum uci_option_type type
;
437 struct uci_list list
;
452 struct uci_element e
;
453 enum uci_command cmd
;
459 /* linked list handling */
461 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
465 * container_of - cast a member of a structure out to the containing structure
466 * @ptr: the pointer to the member.
467 * @type: the type of the container struct this is embedded in.
468 * @member: the name of the member within the struct.
470 #define container_of(ptr, type, member) \
471 ((type *) ((char *)ptr - offsetof(type,member)))
475 * uci_list_entry: casts an uci_list pointer to the containing struct.
476 * @_type: config, section or option
477 * @_ptr: pointer to the uci_list struct
479 #define list_to_element(ptr) \
480 container_of(ptr, struct uci_element, list)
483 * uci_foreach_entry: loop through a list of uci elements
484 * @_list: pointer to the uci_list struct
485 * @_ptr: iteration variable, struct uci_element
487 * use like a for loop, e.g:
488 * uci_foreach(&list, p) {
492 #define uci_foreach_element(_list, _ptr) \
493 for(_ptr = list_to_element((_list)->next); \
494 &_ptr->list != (_list); \
495 _ptr = list_to_element(_ptr->list.next))
498 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
499 * @_list: pointer to the uci_list struct
500 * @_tmp: temporary variable, struct uci_element *
501 * @_ptr: iteration variable, struct uci_element *
503 * use like a for loop, e.g:
504 * uci_foreach(&list, p) {
508 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
509 for(_ptr = list_to_element((_list)->next), \
510 _tmp = list_to_element(_ptr->list.next); \
511 &_ptr->list != (_list); \
512 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
515 * uci_list_empty: returns true if a list is empty
518 #define uci_list_empty(list) ((list)->next == (list))
520 /* wrappers for dynamic type handling */
521 #define uci_type_backend UCI_TYPE_BACKEND
522 #define uci_type_history UCI_TYPE_HISTORY
523 #define uci_type_package UCI_TYPE_PACKAGE
524 #define uci_type_section UCI_TYPE_SECTION
525 #define uci_type_option UCI_TYPE_OPTION
527 /* element typecasting */
528 #ifdef UCI_DEBUG_TYPECAST
529 static const char *uci_typestr
[] = {
530 [uci_type_backend
] = "backend",
531 [uci_type_history
] = "history",
532 [uci_type_package
] = "package",
533 [uci_type_section
] = "section",
534 [uci_type_option
] = "option",
537 static void uci_typecast_error(int from
, int to
)
539 fprintf(stderr
, "Invalid typecast from '%s' to '%s'\n", uci_typestr
[from
], uci_typestr
[to
]);
542 #define BUILD_CAST(_type) \
543 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
545 if (e->type != uci_type_ ## _type) { \
546 uci_typecast_error(e->type, uci_type_ ## _type); \
548 return (struct uci_ ## _type *) e; \
558 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
559 #define uci_to_history(ptr) container_of(ptr, struct uci_history, e)
560 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
561 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
562 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
566 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
568 * @type: {package,section,option}
569 * @name: string containing the name of the element
570 * @datasize: additional buffer size to reserve at the end of the struct
572 #define uci_alloc_element(ctx, type, name, datasize) \
573 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
575 #define uci_dataptr(ptr) \
576 (((char *) ptr) + sizeof(*ptr))