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 Lesser General Public License for more details.
22 #include "uci_config.h"
25 * you can use these defines to enable debugging behavior for
26 * apps compiled against libuci:
28 * #define UCI_DEBUG_TYPECAST:
29 * enable uci_element typecast checking at run time
38 #define UCI_CONFDIR "/etc/config"
39 #define UCI_SAVEDIR "/tmp/.uci"
40 #define UCI_DIRMODE 0700
41 #define UCI_FILEMODE 0600
59 struct uci_list *next;
60 struct uci_list *prev;
72 struct uci_parse_option;
73 struct uci_parse_context;
77 * uci_alloc_context: Allocate a new uci context
79 extern struct uci_context *uci_alloc_context(void);
82 * uci_free_context: Free the uci context including all of its data
84 extern void uci_free_context(struct uci_context *ctx);
87 * uci_perror: Print the last uci error that occured
89 * @str: string to print before the error message
91 extern void uci_perror(struct uci_context *ctx, const char *str);
94 * uci_geterror: Get an error string for the last uci error
96 * @dest: target pointer for the string
97 * @str: prefix for the error message
99 * Note: string must be freed by the caller
101 extern void uci_get_errorstr(struct uci_context *ctx, char **dest, const char *str);
104 * uci_import: Import uci config data from a stream
106 * @stream: file stream to import from
107 * @name: (optional) assume the config has the given name
108 * @package: (optional) store the last parsed config package in this variable
109 * @single: ignore the 'package' keyword and parse everything into a single package
111 * the name parameter is for config files that don't explicitly use the 'package <...>' keyword
112 * if 'package' points to a non-null struct pointer, enable delta tracking and merge
114 extern int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single);
117 * uci_export: Export one or all uci config packages
119 * @stream: output stream
120 * @package: (optional) uci config package to export
121 * @header: include the package header
123 extern int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header);
126 * uci_load: Parse an uci config file and store it in the uci context
129 * @name: name of the config file (relative to the config directory)
130 * @package: store the loaded config package in this variable
132 extern int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package);
135 * uci_unload: Unload a config file from the uci context
138 * @package: pointer to the uci_package struct
140 extern int uci_unload(struct uci_context *ctx, struct uci_package *p);
143 * uci_lookup_ptr: Split an uci tuple string and look up an element tree
145 * @ptr: lookup result struct
146 * @str: uci tuple string to look up
147 * @extended: allow extended syntax lookup
149 * if extended is set to true, uci_lookup_ptr supports the following
153 * network.@interface[0].ifname ('ifname' option of the first interface section)
154 * network.@interface[-1] (last interface section)
155 * Note: uci_lookup_ptr will automatically load a config package if necessary
156 * @str must not be constant, as it will be modified and used for the strings inside @ptr,
157 * thus it must also be available as long as @ptr is in use.
159 extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
162 * uci_add_section: Add an unnamed section
164 * @p: package to add the section to
165 * @type: section type
166 * @res: pointer to store a reference to the new section in
168 extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res);
171 * uci_set: Set an element's value; create the element if necessary
175 * The updated/created element is stored in ptr->last
177 extern int uci_set(struct uci_context *ctx, struct uci_ptr *ptr);
180 * uci_add_list: Append a string to an element list
182 * @ptr: uci pointer (with value)
184 * Note: if the given option already contains a string value,
185 * it will be converted to an 1-element-list before appending the next element
187 extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
190 * uci_del_list: Remove a string from an element list
192 * @ptr: uci pointer (with value)
195 extern int uci_del_list(struct uci_context *ctx, struct uci_ptr *ptr);
198 * uci_reorder: Reposition a section
200 * @s: uci section to reposition
201 * @pos: new position in the section list
203 extern int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos);
206 * uci_rename: Rename an element
208 * @ptr: uci pointer (with value)
210 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
213 * uci_delete: Delete a section or option
217 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
220 * uci_save: save change delta for a package
222 * @p: uci_package struct
224 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
227 * uci_commit: commit changes to a package
229 * @p: uci_package struct pointer
230 * @overwrite: overwrite existing config data and flush delta
232 * committing may reload the whole uci_package data,
233 * the supplied pointer is updated accordingly
235 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
238 * uci_list_configs: List available uci config files
241 * caller is responsible for freeing the allocated memory behind list
243 extern int uci_list_configs(struct uci_context *ctx, char ***list);
246 * uci_set_savedir: override the default delta save directory
248 * @dir: directory name
250 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
253 * uci_set_savedir: override the default config storage directory
255 * @dir: directory name
257 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
260 * uci_add_delta_path: add a directory to the search path for change delta files
262 * @dir: directory name
264 * This function allows you to add directories, which contain 'overlays'
265 * for the active config, that will never be committed.
267 extern int uci_add_delta_path(struct uci_context *ctx, const char *dir);
270 * uci_revert: revert all changes to a config item
274 extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr);
277 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
279 * @stream: input stream
280 * @str: pointer to the current line (use NULL for parsing the next line)
281 * @result: pointer for the result
283 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
286 * uci_set_backend: change the default backend
288 * @name: name of the backend
290 * The default backend is "file", which uses /etc/config for config storage
292 extern int uci_set_backend(struct uci_context *ctx, const char *name);
295 * uci_validate_text: validate a value string for uci options
298 * this function checks whether a given string is acceptable as value
301 extern bool uci_validate_text(const char *str);
305 * uci_add_hook: add a uci hook
309 * NB: allocated and freed by the caller
311 extern int uci_add_hook(struct uci_context *ctx, const struct uci_hook_ops *ops);
314 * uci_remove_hook: remove a uci hook
318 extern int uci_remove_hook(struct uci_context *ctx, const struct uci_hook_ops *ops);
321 * uci_parse_ptr: parse a uci string into a uci_ptr
323 * @ptr: target data structure
324 * @str: string to parse
326 * str is modified by this function
328 int uci_parse_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str);
331 * uci_lookup_next: lookup a child element
333 * @e: target element pointer
334 * @list: list of elements
335 * @name: name of the child element
337 * if parent is NULL, the function looks up the package with the given name
339 int uci_lookup_next(struct uci_context *ctx, struct uci_element **e, struct uci_list *list, const char *name);
342 * uci_parse_section: look up a set of options
344 * @opts: list of options to look up
345 * @n_opts: number of options to look up
346 * @tb: array of pointers to found options
348 void uci_parse_section(struct uci_section *s, const struct uci_parse_option *opts,
349 int n_opts, struct uci_option **tb);
352 * uci_hash_options: build a hash over a list of options
353 * @tb: list of option pointers
354 * @n_opts: number of options
356 uint32_t uci_hash_options(struct uci_option **tb, int n_opts);
359 /* UCI data structures */
363 UCI_TYPE_PACKAGE = 2,
364 UCI_TYPE_SECTION = 3,
367 UCI_TYPE_BACKEND = 6,
372 enum uci_option_type {
378 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
379 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
380 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
381 UCI_FLAG_SAVED_DELTA = (1 << 3), /* store the saved delta in memory as well */
386 struct uci_list list;
393 struct uci_element e;
394 char **(*list_configs)(struct uci_context *ctx);
395 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
396 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
405 /* list of config packages */
406 struct uci_list root;
408 /* parser context, use for error handling only */
409 struct uci_parse_context *pctx;
411 /* backend for import and export */
412 struct uci_backend *backend;
413 struct uci_list backends;
415 /* uci runtime flags */
416 enum uci_flags flags;
421 /* search path for delta files */
422 struct uci_list delta_path;
428 bool internal, nested;
432 struct uci_list hooks;
437 struct uci_element e;
438 struct uci_list sections;
439 struct uci_context *ctx;
444 struct uci_backend *backend;
447 struct uci_list delta;
448 struct uci_list saved_delta;
453 struct uci_element e;
454 struct uci_list options;
455 struct uci_package *package;
462 struct uci_element e;
463 struct uci_section *section;
464 enum uci_option_type type;
466 struct uci_list list;
483 struct uci_element e;
484 enum uci_command cmd;
491 enum uci_type target;
493 UCI_LOOKUP_DONE = (1 << 0),
494 UCI_LOOKUP_COMPLETE = (1 << 1),
495 UCI_LOOKUP_EXTENDED = (1 << 2),
498 struct uci_package *p;
499 struct uci_section *s;
500 struct uci_option *o;
501 struct uci_element *last;
511 void (*load)(const struct uci_hook_ops *ops, struct uci_package *p);
512 void (*set)(const struct uci_hook_ops *ops, struct uci_package *p, struct uci_delta *e);
517 struct uci_element e;
518 const struct uci_hook_ops *ops;
521 struct uci_parse_option {
523 enum uci_option_type type;
527 /* linked list handling */
529 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
533 * container_of - cast a member of a structure out to the containing structure
534 * @ptr: the pointer to the member.
535 * @type: the type of the container struct this is embedded in.
536 * @member: the name of the member within the struct.
539 #define container_of(ptr, type, member) \
540 ((type *) ((char *)ptr - offsetof(type,member)))
545 * uci_list_entry: casts an uci_list pointer to the containing struct.
546 * @_type: config, section or option
547 * @_ptr: pointer to the uci_list struct
549 #define list_to_element(ptr) \
550 container_of(ptr, struct uci_element, list)
553 * uci_foreach_entry: loop through a list of uci elements
554 * @_list: pointer to the uci_list struct
555 * @_ptr: iteration variable, struct uci_element
557 * use like a for loop, e.g:
558 * uci_foreach(&list, p) {
562 #define uci_foreach_element(_list, _ptr) \
563 for(_ptr = list_to_element((_list)->next); \
564 &_ptr->list != (_list); \
565 _ptr = list_to_element(_ptr->list.next))
568 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
569 * @_list: pointer to the uci_list struct
570 * @_tmp: temporary variable, struct uci_element *
571 * @_ptr: iteration variable, struct uci_element *
573 * use like a for loop, e.g:
574 * uci_foreach(&list, p) {
578 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
579 for(_ptr = list_to_element((_list)->next), \
580 _tmp = list_to_element(_ptr->list.next); \
581 &_ptr->list != (_list); \
582 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
585 * uci_list_empty: returns true if a list is empty
588 #define uci_list_empty(list) ((list)->next == (list))
590 /* wrappers for dynamic type handling */
591 #define uci_type_backend UCI_TYPE_BACKEND
592 #define uci_type_delta UCI_TYPE_DELTA
593 #define uci_type_package UCI_TYPE_PACKAGE
594 #define uci_type_section UCI_TYPE_SECTION
595 #define uci_type_option UCI_TYPE_OPTION
596 #define uci_type_hook UCI_TYPE_HOOK
598 /* element typecasting */
599 #ifdef UCI_DEBUG_TYPECAST
600 static const char *uci_typestr[] = {
601 [uci_type_backend] = "backend",
602 [uci_type_delta] = "delta",
603 [uci_type_package] = "package",
604 [uci_type_section] = "section",
605 [uci_type_option] = "option",
606 [uci_type_hook] = "hook",
609 static void uci_typecast_error(int from, int to)
611 fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]);
614 #define BUILD_CAST(_type) \
615 static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \
617 if (e->type != uci_type_ ## _type) { \
618 uci_typecast_error(e->type, uci_type_ ## _type); \
620 return (struct uci_ ## _type *) e; \
631 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
632 #define uci_to_delta(ptr) container_of(ptr, struct uci_delta, e)
633 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
634 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
635 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
636 #define uci_to_hook(ptr) container_of(ptr, struct uci_hook, e)
640 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
642 * @type: {package,section,option}
643 * @name: string containing the name of the element
644 * @datasize: additional buffer size to reserve at the end of the struct
646 #define uci_alloc_element(ctx, type, name, datasize) \
647 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
649 #define uci_dataptr(ptr) \
650 (((char *) ptr) + sizeof(*ptr))
653 * uci_lookup_package: look up a package
655 * @name: name of the package
657 static inline struct uci_package *
658 uci_lookup_package(struct uci_context *ctx, const char *name)
660 struct uci_element *e = NULL;
661 if (uci_lookup_next(ctx, &e, &ctx->root, name) == 0)
662 return uci_to_package(e);
668 * uci_lookup_section: look up a section
670 * @p: package that the section belongs to
671 * @name: name of the section
673 static inline struct uci_section *
674 uci_lookup_section(struct uci_context *ctx, struct uci_package *p, const char *name)
676 struct uci_element *e = NULL;
677 if (uci_lookup_next(ctx, &e, &p->sections, name) == 0)
678 return uci_to_section(e);
684 * uci_lookup_option: look up an option
686 * @section: section that the option belongs to
687 * @name: name of the option
689 static inline struct uci_option *
690 uci_lookup_option(struct uci_context *ctx, struct uci_section *s, const char *name)
692 struct uci_element *e = NULL;
693 if (uci_lookup_next(ctx, &e, &s->options, name) == 0)
694 return uci_to_option(e);
699 static inline const char *
700 uci_lookup_option_string(struct uci_context *ctx, struct uci_section *s, const char *name)
702 struct uci_option *o;
704 o = uci_lookup_option(ctx, s, name);
705 if (!o || o->type != UCI_TYPE_STRING)