1 /* 2 * SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #ifndef __CONFIG_H__ 8 #define __CONFIG_H__ 9 10 // This module implements a configuration parser. Clients can query the 11 // contents of a configuration file through the interface provided here. 12 // The current implementation is read-only; mutations are only kept in 13 // memory. This parser supports the INI file format. 14 15 // Implementation notes: 16 // - Key/value pairs that are not within a section are assumed to be under 17 // the |CONFIG_DEFAULT_SECTION| section. 18 // - Multiple sections with the same name will be merged as if they were in 19 // a single section. 20 // - Empty sections with no key/value pairs will be treated as if they do 21 // not exist. In other words, |config_has_section| will return false for 22 // empty sections. 23 // - Duplicate keys in a section will overwrite previous values. 24 // - All strings are case sensitive. 25 26 #include <stdbool.h> 27 28 // The default section name to use if a key/value pair is not defined within 29 // a section. 30 #define CONFIG_DEFAULT_SECTION "Global" 31 32 typedef struct config_t config_t; 33 typedef struct config_section_node_t config_section_node_t; 34 35 // Creates a new config object with no entries (i.e. not backed by a file). 36 // This function returns a config object or NULL on error. Clients must call 37 // |config_free| on the returned handle when it is no longer required. 38 config_t *config_new_empty(void); 39 40 // Loads the specified file and returns a handle to the config file. If there 41 // was a problem loading the file or allocating memory, this function returns 42 // NULL. Clients must call |config_free| on the returned handle when it is no 43 // longer required. |filename| must not be NULL and must point to a readable 44 // file on the filesystem. 45 config_t *config_new(const char *filename); 46 47 // Frees resources associated with the config file. No further operations may 48 // be performed on the |config| object after calling this function. |config| 49 // may be NULL. 50 void config_free(config_t *config); 51 52 // Returns true if the config file contains a section named |section|. If 53 // the section has no key/value pairs in it, this function will return false. 54 // |config| and |section| must not be NULL. 55 bool config_has_section(const config_t *config, const char *section); 56 57 // Returns true if the config file has a key named |key| under |section|. 58 // Returns false otherwise. |config|, |section|, and |key| must not be NULL. 59 bool config_has_key(const config_t *config, const char *section, const char *key); 60 61 // Returns true if the config file has a key named |key| and the key_value. 62 // Returns false otherwise. |config|, |key|, and |key_value| must not be NULL. 63 bool config_has_key_in_section(config_t *config, const char *key, char *key_value); 64 65 // Returns the integral value for a given |key| in |section|. If |section| 66 // or |key| do not exist, or the value cannot be fully converted to an integer, 67 // this function returns |def_value|. |config|, |section|, and |key| must not 68 // be NULL. 69 int config_get_int(const config_t *config, const char *section, const char *key, int def_value); 70 71 // Returns the boolean value for a given |key| in |section|. If |section| 72 // or |key| do not exist, or the value cannot be converted to a boolean, this 73 // function returns |def_value|. |config|, |section|, and |key| must not be NULL. 74 bool config_get_bool(const config_t *config, const char *section, const char *key, bool def_value); 75 76 // Returns the string value for a given |key| in |section|. If |section| or 77 // |key| do not exist, this function returns |def_value|. The returned string 78 // is owned by the config module and must not be freed. |config|, |section|, 79 // and |key| must not be NULL. |def_value| may be NULL. 80 const char *config_get_string(const config_t *config, const char *section, const char *key, const char *def_value); 81 82 // Sets an integral value for the |key| in |section|. If |key| or |section| do 83 // not already exist, this function creates them. |config|, |section|, and |key| 84 // must not be NULL. 85 void config_set_int(config_t *config, const char *section, const char *key, int value); 86 87 // Sets a boolean value for the |key| in |section|. If |key| or |section| do 88 // not already exist, this function creates them. |config|, |section|, and |key| 89 // must not be NULL. 90 void config_set_bool(config_t *config, const char *section, const char *key, bool value); 91 92 // Sets a string value for the |key| in |section|. If |key| or |section| do 93 // not already exist, this function creates them. |config|, |section|, |key|, and 94 // |value| must not be NULL. 95 void config_set_string(config_t *config, const char *section, const char *key, const char *value, bool insert_back); 96 97 // Removes |section| from the |config| (and, as a result, all keys in the section). 98 // Returns true if |section| was found and removed from |config|, false otherwise. 99 // Neither |config| nor |section| may be NULL. 100 bool config_remove_section(config_t *config, const char *section); 101 102 // Removes one specific |key| residing in |section| of the |config|. Returns true 103 // if the section and key were found and the key was removed, false otherwise. 104 // None of |config|, |section|, or |key| may be NULL. 105 bool config_remove_key(config_t *config, const char *section, const char *key); 106 107 // Returns an iterator to the first section in the config file. If there are no 108 // sections, the iterator will equal the return value of |config_section_end|. 109 // The returned pointer must be treated as an opaque handle and must not be freed. 110 // The iterator is invalidated on any config mutating operation. |config| may not 111 // be NULL. 112 const config_section_node_t *config_section_begin(const config_t *config); 113 114 // Returns an iterator to one past the last section in the config file. It does not 115 // represent a valid section, but can be used to determine if all sections have been 116 // iterated over. The returned pointer must be treated as an opaque handle and must 117 // not be freed and must not be iterated on (must not call |config_section_next| on 118 // it). |config| may not be NULL. 119 const config_section_node_t *config_section_end(const config_t *config); 120 121 // Moves |iter| to the next section. If there are no more sections, |iter| will 122 // equal the value of |config_section_end|. |iter| may not be NULL and must be 123 // a pointer returned by either |config_section_begin| or |config_section_next|. 124 const config_section_node_t *config_section_next(const config_section_node_t *iter); 125 126 // Returns the name of the section referred to by |iter|. The returned pointer is 127 // owned by the config module and must not be freed by the caller. The pointer will 128 // remain valid until |config_free| is called. |iter| may not be NULL and must not 129 // equal the value returned by |config_section_end|. 130 const char *config_section_name(const config_section_node_t *iter); 131 132 // Saves |config| to a file given by |filename|. Note that this could be a destructive 133 // operation: if |filename| already exists, it will be overwritten. The config 134 // module does not preserve comments or formatting so if a config file was opened 135 // with |config_new| and subsequently overwritten with |config_save|, all comments 136 // and special formatting in the original file will be lost. Neither |config| nor 137 // |filename| may be NULL. 138 bool config_save(const config_t *config, const char *filename); 139 140 #endif /* #ifndef __CONFIG_H__ */ 141
