/* * libuci - Library for the Unified Configuration Interface * Copyright (C) 2008 Felix Fietkau * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License version 2.1 * as published by the Free Software Foundation * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. */ #ifndef __LIBUCI_H #define __LIBUCI_H #ifdef __cplusplus extern "C" { #endif #include "uci_config.h" /* * you can use these defines to enable debugging behavior for * apps compiled against libuci: * * #define UCI_DEBUG_TYPECAST: * enable uci_element typecast checking at run time * */ #include #include #include #include #include #define UCI_CONFDIR "/etc/config" #define UCI_SAVEDIR "/tmp/.uci" #define UCI_DIRMODE 0700 #define UCI_FILEMODE 0600 enum { UCI_OK = 0, UCI_ERR_MEM, UCI_ERR_INVAL, UCI_ERR_NOTFOUND, UCI_ERR_IO, UCI_ERR_PARSE, UCI_ERR_DUPLICATE, UCI_ERR_UNKNOWN, UCI_ERR_LAST }; struct uci_list; struct uci_list { struct uci_list *next; struct uci_list *prev; }; struct uci_ptr; struct uci_element; struct uci_package; struct uci_section; struct uci_option; struct uci_delta; struct uci_context; struct uci_backend; struct uci_parse_option; struct uci_parse_context; /** * uci_alloc_context: Allocate a new uci context */ extern struct uci_context *uci_alloc_context(void); /** * uci_free_context: Free the uci context including all of its data */ extern void uci_free_context(struct uci_context *ctx); /** * uci_perror: Print the last uci error that occured * @ctx: uci context * @str: string to print before the error message */ extern void uci_perror(struct uci_context *ctx, const char *str); /** * uci_geterror: Get an error string for the last uci error * @ctx: uci context * @dest: target pointer for the string * @str: prefix for the error message * * Note: string must be freed by the caller */ extern void uci_get_errorstr(struct uci_context *ctx, char **dest, const char *str); /** * uci_import: Import uci config data from a stream * @ctx: uci context * @stream: file stream to import from * @name: (optional) assume the config has the given name * @package: (optional) store the last parsed config package in this variable * @single: ignore the 'package' keyword and parse everything into a single package * * the name parameter is for config files that don't explicitly use the 'package <...>' keyword * if 'package' points to a non-null struct pointer, enable delta tracking and merge */ extern int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single); /** * uci_export: Export one or all uci config packages * @ctx: uci context * @stream: output stream * @package: (optional) uci config package to export * @header: include the package header */ extern int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header); /** * uci_load: Parse an uci config file and store it in the uci context * * @ctx: uci context * @name: name of the config file (relative to the config directory) * @package: store the loaded config package in this variable */ extern int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package); /** * uci_unload: Unload a config file from the uci context * * @ctx: uci context * @package: pointer to the uci_package struct */ extern int uci_unload(struct uci_context *ctx, struct uci_package *p); /** * uci_lookup_ptr: Split an uci tuple string and look up an element tree * @ctx: uci context * @ptr: lookup result struct * @str: uci tuple string to look up * @extended: allow extended syntax lookup * * if extended is set to true, uci_lookup_ptr supports the following * extended syntax: * * Examples: * network.@interface[0].ifname ('ifname' option of the first interface section) * network.@interface[-1] (last interface section) * Note: uci_lookup_ptr will automatically load a config package if necessary * @str must not be constant, as it will be modified and used for the strings inside @ptr, * thus it must also be available as long as @ptr is in use. * * This function returns UCI_ERR_NOTFOUND if the package specified in the tuple * string cannot be found. Otherwise it will return UCI_OK. * * Note that failures in looking up other parts, if they are also specfied, * including section and option, will also have a return value UCI_OK but with * ptr->flags * UCI_LOOKUP_COMPLETE not set. */ extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended); /** * uci_add_section: Add an unnamed section * @ctx: uci context * @p: package to add the section to * @type: section type * @res: pointer to store a reference to the new section in */ extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res); /** * uci_set: Set an element's value; create the element if necessary * @ctx: uci context * @ptr: uci pointer * * The updated/created element is stored in ptr->last */ extern int uci_set(struct uci_context *ctx, struct uci_ptr *ptr); /** * uci_add_list: Append a string to an element list * @ctx: uci context * @ptr: uci pointer (with value) * * Note: if the given option already contains a string value, * it will be converted to an 1-element-list before appending the next element */ extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr); /** * uci_del_list: Remove a string from an element list * @ctx: uci context * @ptr: uci pointer (with value) * */ extern int uci_del_list(struct uci_context *ctx, struct uci_ptr *ptr); /** * uci_reorder: Reposition a section * @ctx: uci context * @s: uci section to reposition * @pos: new position in the section list */ extern int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos); /** * uci_rename: Rename an element * @ctx: uci context * @ptr: uci pointer (with value) */ extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr); /** * uci_delete: Delete a section or option * @ctx: uci context * @ptr: uci pointer */ extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr); /** * uci_save: save change delta for a package * @ctx: uci context * @p: uci_package struct */ extern int uci_save(struct uci_context *ctx, struct uci_package *p); /** * uci_commit: commit changes to a package * @ctx: uci context * @p: uci_package struct pointer * @overwrite: overwrite existing config data and flush delta * * committing may reload the whole uci_package data, * the supplied pointer is updated accordingly */ extern int uci_commit(struct uci_context *ctx, struct uci_package **p, bool overwrite); /** * uci_list_configs: List available uci config files * @ctx: uci context * * caller is responsible for freeing the allocated memory behind list */ extern int uci_list_configs(struct uci_context *ctx, char ***list); /** * uci_set_savedir: override the default delta save directory * @ctx: uci context * @dir: directory name * * This will also try adding the specified dir to the end of delta pathes. */ extern int uci_set_savedir(struct uci_context *ctx, const char *dir); /** * uci_set_savedir: override the default config storage directory * @ctx: uci context * @dir: directory name */ extern int uci_set_confdir(struct uci_context *ctx, const char *dir); /** * uci_add_delta_path: add a directory to the search path for change delta files * @ctx: uci context * @dir: directory name * * This function allows you to add directories, which contain 'overlays' * for the active config, that will never be committed. * * Adding a duplicate directory will cause UCI_ERR_DUPLICATE be returned. */ extern int uci_add_delta_path(struct uci_context *ctx, const char *dir); /** * uci_revert: revert all changes to a config item * @ctx: uci context * @ptr: uci pointer */ extern int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr); /** * uci_parse_argument: parse a shell-style argument, with an arbitrary quoting style * @ctx: uci context * @stream: input stream * @str: pointer to the current line (use NULL for parsing the next line) * @result: pointer for the result */ extern int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result); /** * uci_set_backend: change the default backend * @ctx: uci context * @name: name of the backend * * The default backend is "file", which uses /etc/config for config storage */ extern int uci_set_backend(struct uci_context *ctx, const char *name); /** * uci_validate_text: validate a value string for uci options * @str: value * * this function checks whether a given string is acceptable as value * for uci options */ extern bool uci_validate_text(const char *str); /** * uci_parse_ptr: parse a uci string into a uci_ptr * @ctx: uci context * @ptr: target data structure * @str: string to parse * * str is modified by this function */ int uci_parse_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str); /** * uci_lookup_next: lookup a child element * @ctx: uci context * @e: target element pointer * @list: list of elements * @name: name of the child element * * if parent is NULL, the function looks up the package with the given name */ int uci_lookup_next(struct uci_context *ctx, struct uci_element **e, struct uci_list *list, const char *name); /** * uci_parse_section: look up a set of options * @s: uci section * @opts: list of options to look up * @n_opts: number of options to look up * @tb: array of pointers to found options */ void uci_parse_section(struct uci_section *s, const struct uci_parse_option *opts, int n_opts, struct uci_option **tb); /** * uci_hash_options: build a hash over a list of options * @tb: list of option pointers * @n_opts: number of options */ uint32_t uci_hash_options(struct uci_option **tb, int n_opts); /* UCI data structures */ enum uci_type { UCI_TYPE_UNSPEC = 0, UCI_TYPE_DELTA = 1, UCI_TYPE_PACKAGE = 2, UCI_TYPE_SECTION = 3, UCI_TYPE_OPTION = 4, UCI_TYPE_PATH = 5, UCI_TYPE_BACKEND = 6, UCI_TYPE_ITEM = 7, UCI_TYPE_HOOK = 8, }; enum uci_option_type { UCI_TYPE_STRING = 0, UCI_TYPE_LIST = 1, }; enum uci_flags { UCI_FLAG_STRICT = (1 << 0), /* strict mode for the parser */ UCI_FLAG_PERROR = (1 << 1), /* print parser error messages */ UCI_FLAG_EXPORT_NAME = (1 << 2), /* when exporting, name unnamed sections */ UCI_FLAG_SAVED_DELTA = (1 << 3), /* store the saved delta in memory as well */ }; struct uci_element { struct uci_list list; enum uci_type type; char *name; }; struct uci_backend { struct uci_element e; char **(*list_configs)(struct uci_context *ctx); struct uci_package *(*load)(struct uci_context *ctx, const char *name); void (*commit)(struct uci_context *ctx, struct uci_package **p, bool overwrite); /* private: */ const void *ptr; void *priv; }; struct uci_context { /* list of config packages */ struct uci_list root; /* parser context, use for error handling only */ struct uci_parse_context *pctx; /* backend for import and export */ struct uci_backend *backend; struct uci_list backends; /* uci runtime flags */ enum uci_flags flags; char *confdir; char *savedir; /* search path for delta files */ struct uci_list delta_path; /* private: */ int err; const char *func; jmp_buf trap; bool internal, nested; char *buf; int bufsz; }; struct uci_package { struct uci_element e; struct uci_list sections; struct uci_context *ctx; bool has_delta; char *path; /* private: */ struct uci_backend *backend; void *priv; int n_section; struct uci_list delta; struct uci_list saved_delta; }; struct uci_section { struct uci_element e; struct uci_list options; struct uci_package *package; bool anonymous; char *type; }; struct uci_option { struct uci_element e; struct uci_section *section; enum uci_option_type type; union { struct uci_list list; char *string; } v; }; /* * UCI_CMD_ADD is used for anonymous sections or list values */ enum uci_command { UCI_CMD_ADD, UCI_CMD_REMOVE, UCI_CMD_CHANGE, UCI_CMD_RENAME, UCI_CMD_REORDER, UCI_CMD_LIST_ADD, UCI_CMD_LIST_DEL, __UCI_CMD_MAX, __UCI_CMD_LAST = __UCI_CMD_MAX - 1 }; extern char const uci_command_char[]; struct uci_delta { struct uci_element e; enum uci_command cmd; char *section; char *value; }; struct uci_ptr { enum uci_type target; enum { UCI_LOOKUP_DONE = (1 << 0), UCI_LOOKUP_COMPLETE = (1 << 1), UCI_LOOKUP_EXTENDED = (1 << 2), } flags; struct uci_package *p; struct uci_section *s; struct uci_option *o; struct uci_element *last; const char *package; const char *section; const char *option; const char *value; }; struct uci_parse_option { const char *name; enum uci_option_type type; }; /** * container_of - cast a member of a structure out to the containing structure * @ptr: the pointer to the member. * @type: the type of the container struct this is embedded in. * @member: the name of the member within the struct. */ #ifndef container_of #define container_of(ptr, type, member) \ ((type *) ((char *)ptr - offsetof(type,member))) #endif /** * uci_list_entry: casts an uci_list pointer to the containing struct. * @_type: config, section or option * @_ptr: pointer to the uci_list struct */ #define list_to_element(ptr) \ container_of(ptr, struct uci_element, list) /** * uci_foreach_entry: loop through a list of uci elements * @_list: pointer to the uci_list struct * @_ptr: iteration variable, struct uci_element * * use like a for loop, e.g: * uci_foreach(&list, p) { * ... * } */ #define uci_foreach_element(_list, _ptr) \ for(_ptr = list_to_element((_list)->next); \ &_ptr->list != (_list); \ _ptr = list_to_element(_ptr->list.next)) /** * uci_foreach_entry_safe: like uci_foreach_safe, but safe for deletion * @_list: pointer to the uci_list struct * @_tmp: temporary variable, struct uci_element * * @_ptr: iteration variable, struct uci_element * * * use like a for loop, e.g: * uci_foreach(&list, p) { * ... * } */ #define uci_foreach_element_safe(_list, _tmp, _ptr) \ for(_ptr = list_to_element((_list)->next), \ _tmp = list_to_element(_ptr->list.next); \ &_ptr->list != (_list); \ _ptr = _tmp, _tmp = list_to_element(_ptr->list.next)) /** * uci_list_empty: returns true if a list is empty * @list: list head */ #define uci_list_empty(list) ((list)->next == (list)) /* wrappers for dynamic type handling */ #define uci_type_backend UCI_TYPE_BACKEND #define uci_type_delta UCI_TYPE_DELTA #define uci_type_package UCI_TYPE_PACKAGE #define uci_type_section UCI_TYPE_SECTION #define uci_type_option UCI_TYPE_OPTION /* element typecasting */ #ifdef UCI_DEBUG_TYPECAST static const char *uci_typestr[] = { [uci_type_backend] = "backend", [uci_type_delta] = "delta", [uci_type_package] = "package", [uci_type_section] = "section", [uci_type_option] = "option", }; static void uci_typecast_error(int from, int to) { fprintf(stderr, "Invalid typecast from '%s' to '%s'\n", uci_typestr[from], uci_typestr[to]); } #define BUILD_CAST(_type) \ static inline struct uci_ ## _type *uci_to_ ## _type (struct uci_element *e) \ { \ if (e->type != uci_type_ ## _type) { \ uci_typecast_error(e->type, uci_type_ ## _type); \ } \ return (struct uci_ ## _type *) e; \ } BUILD_CAST(backend) BUILD_CAST(delta) BUILD_CAST(package) BUILD_CAST(section) BUILD_CAST(option) #else #define uci_to_backend(ptr) container_of(ptr, struct uci_backend, e) #define uci_to_delta(ptr) container_of(ptr, struct uci_delta, e) #define uci_to_package(ptr) container_of(ptr, struct uci_package, e) #define uci_to_section(ptr) container_of(ptr, struct uci_section, e) #define uci_to_option(ptr) container_of(ptr, struct uci_option, e) #endif /** * uci_alloc_element: allocate a generic uci_element, reserve a buffer and typecast * @ctx: uci context * @type: {package,section,option} * @name: string containing the name of the element * @datasize: additional buffer size to reserve at the end of the struct */ #define uci_alloc_element(ctx, type, name, datasize) \ uci_to_ ## type (uci_alloc_generic(ctx, uci_type_ ## type, name, sizeof(struct uci_ ## type) + datasize)) #define uci_dataptr(ptr) \ (((char *) ptr) + sizeof(*ptr)) /** * uci_lookup_package: look up a package * @ctx: uci context * @name: name of the package */ static inline struct uci_package * uci_lookup_package(struct uci_context *ctx, const char *name) { struct uci_element *e = NULL; if (uci_lookup_next(ctx, &e, &ctx->root, name) == 0) return uci_to_package(e); else return NULL; } /** * uci_lookup_section: look up a section * @ctx: uci context * @p: package that the section belongs to * @name: name of the section */ static inline struct uci_section * uci_lookup_section(struct uci_context *ctx, struct uci_package *p, const char *name) { struct uci_element *e = NULL; if (uci_lookup_next(ctx, &e, &p->sections, name) == 0) return uci_to_section(e); else return NULL; } /** * uci_lookup_option: look up an option * @ctx: uci context * @section: section that the option belongs to * @name: name of the option */ static inline struct uci_option * uci_lookup_option(struct uci_context *ctx, struct uci_section *s, const char *name) { struct uci_element *e = NULL; if (uci_lookup_next(ctx, &e, &s->options, name) == 0) return uci_to_option(e); else return NULL; } static inline const char * uci_lookup_option_string(struct uci_context *ctx, struct uci_section *s, const char *name) { struct uci_option *o; o = uci_lookup_option(ctx, s, name); if (!o || o->type != UCI_TYPE_STRING) return NULL; return o->v.string; } #ifndef BITS_PER_LONG #define BITS_PER_LONG (8 * sizeof(unsigned long)) #endif static inline void uci_bitfield_set(unsigned long *bits, int bit) { bits[bit / BITS_PER_LONG] |= (1UL << (bit % BITS_PER_LONG)); } #ifdef __cplusplus } #endif #endif