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;
68 struct uci_parse_context;
72 * uci_alloc_context: Allocate a new uci context
74 extern struct uci_context *uci_alloc_context(void);
77 * uci_free_context: Free the uci context including all of its data
79 extern void uci_free_context(struct uci_context *ctx);
82 * uci_perror: Print the last uci error that occured
84 * @str: string to print before the error message
86 extern void uci_perror(struct uci_context *ctx, const char *str);
89 * uci_geterror: Get an error string for the last uci error
91 * @dest: target pointer for the string
92 * @str: prefix for the error message
94 * Note: string must be freed by the caller
96 extern void uci_get_errorstr(struct uci_context *ctx, char **dest, 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 delta 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_ptr: Split an uci tuple string and look up an element tree
140 * @ptr: lookup result struct
141 * @str: uci tuple string to look up
142 * @extended: allow extended syntax lookup
144 * if extended is set to true, uci_lookup_ptr supports the following
148 * network.@interface[0].ifname ('ifname' option of the first interface section)
149 * network.@interface[-1] (last interface section)
150 * Note: uci_lookup_ptr will automatically load a config package if necessary
151 * @str must not be constant, as it will be modified and used for the strings inside @ptr,
152 * thus it must also be available as long as @ptr is in use.
154 extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
157 * uci_add_section: Add an unnamed section
159 * @p: package to add the section to
160 * @type: section type
161 * @res: pointer to store a reference to the new section in
163 extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res);
166 * uci_set: Set an element's value; create the element if necessary
170 * The updated/created element is stored in ptr->last
172 extern int uci_set(struct uci_context *ctx, struct uci_ptr *ptr);
175 * uci_add_list: Append a string to an element list
177 * @ptr: uci pointer (with value)
179 * Note: if the given option already contains a string value,
180 * it will be converted to an 1-element-list before appending the next element
182 extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
185 * uci_reorder: Reposition a section
187 * @s: uci section to reposition
188 * @pos: new position in the section list
190 extern int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos);
193 * uci_rename: Rename an element
195 * @ptr: uci pointer (with value)
197 extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
200 * uci_delete: Delete a section or option
204 extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
207 * uci_save: save change delta for a package
209 * @p: uci_package struct
211 extern int uci_save(struct uci_context *ctx, struct uci_package *p);
214 * uci_commit: commit changes to a package
216 * @p: uci_package struct pointer
217 * @overwrite: overwrite existing config data and flush delta
219 * committing may reload the whole uci_package data,
220 * the supplied pointer is updated accordingly
222 extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite);
225 * uci_list_configs: List available uci config files
228 * caller is responsible for freeing the allocated memory behind list
230 extern int uci_list_configs(struct uci_context *ctx, char ***list);
233 * uci_set_savedir: override the default delta save directory
235 * @dir: directory name
237 extern int uci_set_savedir(struct uci_context *ctx, const char *dir);
240 * uci_set_savedir: override the default config storage directory
242 * @dir: directory name
244 extern int uci_set_confdir(struct uci_context *ctx, const char *dir);
247 * uci_add_delta_path: add a directory to the search path for change delta files
249 * @dir: directory name
251 * This function allows you to add directories, which contain 'overlays'
252 * for the active config, that will never be committed.
254 extern int uci_add_delta_path(struct uci_context *ctx, const char *dir);
257 * uci_revert: revert all changes to a config item
261 extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr);
264 * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style
266 * @stream: input stream
267 * @str: pointer to the current line (use NULL for parsing the next line)
268 * @result: pointer for the result
270 extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result);
273 * uci_set_backend: change the default backend
275 * @name: name of the backend
277 * The default backend is "file", which uses /etc/config for config storage
279 extern int uci_set_backend(struct uci_context *ctx, const char *name);
282 * uci_validate_text: validate a value string for uci options
285 * this function checks whether a given string is acceptable as value
288 extern bool uci_validate_text(const char *str);
292 * uci_add_hook: add a uci hook
296 * NB: allocated and freed by the caller
298 extern int uci_add_hook(struct uci_context *ctx, const struct uci_hook_ops *ops);
301 * uci_remove_hook: remove a uci hook
305 extern int uci_remove_hook(struct uci_context *ctx, const struct uci_hook_ops *ops);
308 * uci_load_plugin: load an uci plugin
310 * @filename: path to the uci plugin
312 * NB: plugin will be unloaded automatically when the context is freed
314 int uci_load_plugin(struct uci_context *ctx, const char *filename);
317 * uci_load_plugins: load all uci plugins from a directory
319 * @pattern: pattern of uci plugin files (optional)
321 * if pattern is NULL, then uci_load_plugins will call uci_load_plugin
322 * for uci_*.so in <prefix>/lib/
324 int uci_load_plugins(struct uci_context *ctx, const char *pattern);
327 * uci_parse_ptr: parse a uci string into a uci_ptr
329 * @ptr: target data structure
330 * @str: string to parse
332 * str is modified by this function
334 int uci_parse_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str);
337 * uci_lookup_next: lookup a child element
339 * @e: target element pointer
340 * @list: list of elements
341 * @name: name of the child element
343 * if parent is NULL, the function looks up the package with the given name
345 int uci_lookup_next(struct uci_context *ctx, struct uci_element **e, struct uci_list *list, const char *name);
348 /* UCI data structures */
352 UCI_TYPE_PACKAGE = 2,
353 UCI_TYPE_SECTION = 3,
356 UCI_TYPE_BACKEND = 6,
362 enum uci_option_type {
368 UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */
369 UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */
370 UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */
371 UCI_FLAG_SAVED_DELTA = (1 << 3), /* store the saved delta in memory as well */
376 struct uci_list list;
383 struct uci_element e;
384 char **(*list_configs)(struct uci_context *ctx);
385 struct uci_package *(*load)(struct uci_context *ctx, const char *name);
386 void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite);
395 /* list of config packages */
396 struct uci_list root;
398 /* parser context, use for error handling only */
399 struct uci_parse_context *pctx;
401 /* backend for import and export */
402 struct uci_backend *backend;
403 struct uci_list backends;
405 /* uci runtime flags */
406 enum uci_flags flags;
411 /* search path for delta files */
412 struct uci_list delta_path;
418 bool internal, nested;
422 struct uci_list hooks;
423 struct uci_list plugins;
428 struct uci_element e;
429 struct uci_list sections;
430 struct uci_context *ctx;
435 struct uci_backend *backend;
438 struct uci_list delta;
439 struct uci_list saved_delta;
444 struct uci_element e;
445 struct uci_list options;
446 struct uci_package *package;
453 struct uci_element e;
454 struct uci_section *section;
455 enum uci_option_type type;
457 struct uci_list list;
473 struct uci_element e;
474 enum uci_command cmd;
481 enum uci_type target;
483 UCI_LOOKUP_DONE = (1 << 0),
484 UCI_LOOKUP_COMPLETE = (1 << 1),
485 UCI_LOOKUP_EXTENDED = (1 << 2),
488 struct uci_package *p;
489 struct uci_section *s;
490 struct uci_option *o;
491 struct uci_element *last;
501 void (*load)(const struct uci_hook_ops *ops, struct uci_package *p);
502 void (*set)(const struct uci_hook_ops *ops, struct uci_package *p, struct uci_delta *e);
507 struct uci_element e;
508 const struct uci_hook_ops *ops;
511 struct uci_plugin_ops
513 int (*attach)(struct uci_context *ctx);
514 void (*detach)(struct uci_context *ctx);
519 struct uci_element e;
520 const struct uci_plugin_ops *ops;
525 /* linked list handling */
527 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
531 * container_of - cast a member of a structure out to the containing structure
532 * @ptr: the pointer to the member.
533 * @type: the type of the container struct this is embedded in.
534 * @member: the name of the member within the struct.
537 #define container_of(ptr, type, member) \
538 ((type *) ((char *)ptr - offsetof(type,member)))
543 * uci_list_entry: casts an uci_list pointer to the containing struct.
544 * @_type: config, section or option
545 * @_ptr: pointer to the uci_list struct
547 #define list_to_element(ptr) \
548 container_of(ptr, struct uci_element, list)
551 * uci_foreach_entry: loop through a list of uci elements
552 * @_list: pointer to the uci_list struct
553 * @_ptr: iteration variable, struct uci_element
555 * use like a for loop, e.g:
556 * uci_foreach(&list, p) {
560 #define uci_foreach_element(_list, _ptr) \
561 for(_ptr = list_to_element((_list)->next); \
562 &_ptr->list != (_list); \
563 _ptr = list_to_element(_ptr->list.next))
566 * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion
567 * @_list: pointer to the uci_list struct
568 * @_tmp: temporary variable, struct uci_element *
569 * @_ptr: iteration variable, struct uci_element *
571 * use like a for loop, e.g:
572 * uci_foreach(&list, p) {
576 #define uci_foreach_element_safe(_list, _tmp, _ptr) \
577 for(_ptr = list_to_element((_list)->next), \
578 _tmp = list_to_element(_ptr->list.next); \
579 &_ptr->list != (_list); \
580 _ptr = _tmp, _tmp = list_to_element(_ptr->list.next))
583 * uci_list_empty: returns true if a list is empty
586 #define uci_list_empty(list) ((list)->next == (list))
588 /* wrappers for dynamic type handling */
589 #define uci_type_backend UCI_TYPE_BACKEND
590 #define uci_type_delta UCI_TYPE_DELTA
591 #define uci_type_package UCI_TYPE_PACKAGE
592 #define uci_type_section UCI_TYPE_SECTION
593 #define uci_type_option UCI_TYPE_OPTION
594 #define uci_type_hook UCI_TYPE_HOOK
595 #define uci_type_plugin UCI_TYPE_PLUGIN
597 /* element typecasting */
598 #ifdef UCI_DEBUG_TYPECAST
599 static const char *uci_typestr[] = {
600 [uci_type_backend] = "backend",
601 [uci_type_delta] = "delta",
602 [uci_type_package] = "package",
603 [uci_type_section] = "section",
604 [uci_type_option] = "option",
605 [uci_type_hook] = "hook",
606 [uci_type_plugin] = "plugin",
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; \
632 #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e)
633 #define uci_to_delta(ptr) container_of(ptr, struct uci_delta, e)
634 #define uci_to_package(ptr) container_of(ptr, struct uci_package, e)
635 #define uci_to_section(ptr) container_of(ptr, struct uci_section, e)
636 #define uci_to_option(ptr) container_of(ptr, struct uci_option, e)
637 #define uci_to_hook(ptr) container_of(ptr, struct uci_hook, e)
638 #define uci_to_plugin(ptr) container_of(ptr, struct uci_plugin, e)
642 * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast
644 * @type: {package,section,option}
645 * @name: string containing the name of the element
646 * @datasize: additional buffer size to reserve at the end of the struct
648 #define uci_alloc_element(ctx, type, name, datasize) \
649 uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize))
651 #define uci_dataptr(ptr) \
652 (((char *) ptr) + sizeof(*ptr))
655 * uci_lookup_package: look up a package
657 * @name: name of the package
659 static inline struct uci_package *
660 uci_lookup_package(struct uci_context *ctx, const char *name)
662 struct uci_element *e = NULL;
663 if (uci_lookup_next(ctx, &e, &ctx->root, name) == 0)
664 return uci_to_package(e);
670 * uci_lookup_section: look up a section
672 * @p: package that the section belongs to
673 * @name: name of the section
675 static inline struct uci_section *
676 uci_lookup_section(struct uci_context *ctx, struct uci_package *p, const char *name)
678 struct uci_element *e = NULL;
679 if (uci_lookup_next(ctx, &e, &p->sections, name) == 0)
680 return uci_to_section(e);
686 * uci_lookup_option: look up an option
688 * @section: section that the option belongs to
689 * @name: name of the option
691 static inline struct uci_option *
692 uci_lookup_option(struct uci_context *ctx, struct uci_section *s, const char *name)
694 struct uci_element *e = NULL;
695 if (uci_lookup_next(ctx, &e, &s->options, name) == 0)
696 return uci_to_option(e);
701 static inline const char *
702 uci_lookup_option_string(struct uci_context *ctx, struct uci_section *s, const char *name)
704 struct uci_option *o;
706 o = uci_lookup_option(ctx, s, name);
707 if (!o || o->type != UCI_TYPE_STRING)