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_rename: Rename an element
183 * @ptr: uci pointer (with value)
185 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
188 * uci_delete: Delete a section or option
192 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
195 * uci_save: save change history for a package
197 * @p: uci_package struct
199 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
202 * uci_commit: commit changes to a package
204 * @p: uci_package struct pointer
205 * @overwrite: overwrite existing config data and flush history
207 * committing may reload the whole uci_package data,
208 * the supplied pointer is updated accordingly
210 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
213 * uci_list_configs: List available uci config files
216 * caller is responsible for freeing the allocated memory behind list
218 extern int uci_list_configs(struct uci_context *ctx, char ***list);
221 * uci_set_savedir: override the default history save directory
223 * @dir: directory name
225 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
228 * uci_set_savedir: override the default config storage directory
230 * @dir: directory name
232 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
235 * uci_add_history_path: add a directory to the search path for change history files
237 * @dir: directory name
239 * This function allows you to add directories, which contain 'overlays'
240 * for the active config, that will never be committed.
242 extern int uci_add_history_path(struct uci_context *ctx, const char *dir);
245 * uci_revert: revert all changes to a config item
249 extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr);
252 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
254 * @stream: input stream
255 * @str: pointer to the current line (use NULL for parsing the next line)
256 * @result: pointer for the result
258 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
261 * uci_set_backend: change the default backend
263 * @name: name of the backend
265 * The default backend is "file", which uses /etc/config for config storage
267 extern int uci_set_backend(struct uci_context *ctx, const char *name);
270 * uci_validate_text: validate a value string for uci options
273 * this function checks whether a given string is acceptable as value
276 extern bool uci_validate_text(const char *str);
278 /* UCI data structures */
281 UCI_TYPE_HISTORY = 1,
282 UCI_TYPE_PACKAGE = 2,
283 UCI_TYPE_SECTION = 3,
286 UCI_TYPE_BACKEND = 6,
290 enum uci_option_type {
296 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
297 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
298 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
299 UCI_FLAG_SAVED_HISTORY = (1 << 3), /* store the saved history in memory as well */
304 struct uci_list list;
311 struct uci_element e;
312 char **(*list_configs)(struct uci_context *ctx);
313 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
314 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
323 /* list of config packages */
324 struct uci_list root;
326 /* parser context, use for error handling only */
327 struct uci_parse_context *pctx;
329 /* backend for import and export */
330 struct uci_backend *backend;
331 struct uci_list backends;
333 /* uci runtime flags */
334 enum uci_flags flags;
339 /* search path for history files */
340 struct uci_list history_path;
346 bool internal, nested;
353 struct uci_element e;
354 struct uci_list sections;
355 struct uci_context *ctx;
360 struct uci_backend *backend;
363 struct uci_list history;
364 struct uci_list saved_history;
369 struct uci_element e;
370 struct uci_list options;
371 struct uci_package *package;
378 struct uci_element e;
379 struct uci_section *section;
380 enum uci_option_type type;
382 struct uci_list list;
397 struct uci_element e;
398 enum uci_command cmd;
405 enum uci_type target;
407 UCI_LOOKUP_DONE = (1 << 0),
408 UCI_LOOKUP_COMPLETE = (1 << 1),
409 UCI_LOOKUP_EXTENDED = (1 << 2),
412 struct uci_package *p;
413 struct uci_section *s;
414 struct uci_option *o;
415 struct uci_element *last;
424 /* linked list handling */
426 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
430 * container_of - cast a member of a structure out to the containing structure
431 * @ptr: the pointer to the member.
432 * @type: the type of the container struct this is embedded in.
433 * @member: the name of the member within the struct.
435 #define container_of(ptr, type, member) \
436 ((type *) ((char *)ptr - offsetof(type,member)))
440 * uci_list_entry: casts an uci_list pointer to the containing struct.
441 * @_type: config, section or option
442 * @_ptr: pointer to the uci_list struct
444 #define list_to_element(ptr) \
445 container_of(ptr, struct uci_element, list)
448 * uci_foreach_entry: loop through a list of uci elements
449 * @_list: pointer to the uci_list struct
450 * @_ptr: iteration variable, struct uci_element
452 * use like a for loop, e.g:
453 * uci_foreach(&list, p) {
457 #define uci_foreach_element(_list, _ptr) \
458 for(_ptr = list_to_element((_list)->next); \
459 &_ptr->list != (_list); \
460 _ptr = list_to_element(_ptr->list.next))
463 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
464 * @_list: pointer to the uci_list struct
465 * @_tmp: temporary variable, struct uci_element *
466 * @_ptr: iteration variable, struct uci_element *
468 * use like a for loop, e.g:
469 * uci_foreach(&list, p) {
473 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
474 for(_ptr = list_to_element((_list)->next), \
475 _tmp = list_to_element(_ptr->list.next); \
476 &_ptr->list != (_list); \
477 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
480 * uci_list_empty: returns true if a list is empty
483 #define uci_list_empty(list) ((list)->next == (list))
485 /* wrappers for dynamic type handling */
486 #define uci_type_backend UCI_TYPE_BACKEND
487 #define uci_type_history UCI_TYPE_HISTORY
488 #define uci_type_package UCI_TYPE_PACKAGE
489 #define uci_type_section UCI_TYPE_SECTION
490 #define uci_type_option UCI_TYPE_OPTION
492 /* element typecasting */
493 #ifdef UCI_DEBUG_TYPECAST
494 static const char *uci_typestr[] = {
495 [uci_type_backend] = "backend",
496 [uci_type_history] = "history",
497 [uci_type_package] = "package",
498 [uci_type_section] = "section",
499 [uci_type_option] = "option",
502 static void uci_typecast_error(int from, int to)
504 fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]);
507 #define BUILD_CAST(_type) \
508 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
510 if (e->type != uci_type_ ## _type) { \
511 uci_typecast_error(e->type, uci_type_ ## _type); \
513 return (struct uci_ ## _type *) e; \
523 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
524 #define uci_to_history(ptr) container_of(ptr, struct uci_history, e)
525 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
526 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
527 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
531 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
533 * @type: {package,section,option}
534 * @name: string containing the name of the element
535 * @datasize: additional buffer size to reserve at the end of the struct
537 #define uci_alloc_element(ctx, type, name, datasize) \
538 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
540 #define uci_dataptr(ptr) \
541 (((char *) ptr) + sizeof(*ptr))