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Diffstat (limited to 'libnetdata/config/appconfig.h')
| -rw-r--r-- | libnetdata/config/appconfig.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/libnetdata/config/appconfig.h b/libnetdata/config/appconfig.h new file mode 100644 index 000000000..6ac666d8b --- /dev/null +++ b/libnetdata/config/appconfig.h @@ -0,0 +1,135 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +/* + * This section manages ini config files, like netdata.conf and stream.conf + * + * It is organized like this: + * + * struct config (i.e. netdata.conf or stream.conf) + * .sections = a linked list of struct section + * .mutex = a mutex to protect the above linked list due to multi-threading + * .index = an AVL tree of struct section + * + * struct section (i.e. [global] or [health] of netdata.conf) + * .value = a linked list of struct config_option + * .mutex = a mutex to protect the above linked list due to multi-threading + * .value_index = an AVL tree of struct config_option + * + * struct config_option (ie. a name-value pair for each ini file option) + * + * The following operations on name-value options are supported: + * SET to set the value of an option + * SET DEFAULT to set the value and the default value of an option + * GET to get the value of an option + * EXISTS to check if an option exists + * MOVE to move an option from a section to another section, and/or rename it + * + * GET and SET operations are provided for the following data types: + * STRING + * NUMBER (long long) + * FLOAT (long double) + * BOOLEAN (false, true) + * BOOLEAN ONDEMAND (false, true, auto) + * + * GET and SET operations create struct config_option, if it is not already present. + * This allows netdata to run even without netdata.conf and stream.conf. The internal + * defaults are used to create the structure that should exist in the ini file and the config + * file can be downloaded from the server. + * + * Also 2 operations are supported for the whole config file: + * + * LOAD To load the ini file from disk + * GENERATE To generate the ini file (this is used to download the ini file from the server) + * + * For each option (name-value pair), the system maintains 4 flags: + * LOADED to indicate that the value has been loaded from the file + * USED to indicate that netdata used the value + * CHANGED to indicate that the value has been changed from the loaded value or the internal default value + * CHECKED is used internally for optimization (to avoid an strcmp() every time GET is called). + * + * TODO: + * 1. The linked lists and the mutexes can be removed and the AVL trees can become DICTIONARY. + * This part of the code was written before we add traversal to AVL. + * + * 2. High level data types could be supported, to simplify the rest of the code: + * MULTIPLE CHOICE to let the user select one of the supported keywords + * this would allow users see in comments the available options + * + * SIMPLE PATTERN to let the user define netdata SIMPLE PATTERNS + * + * 3. Sorting of options should be supported. + * Today, when the ini file is downloaded from the server, the options are shown in the order + * they appear in the linked list (the order they were added, listing changed options first). + * If we remove the linked list, the order they appear in the AVL tree will be used (which is + * random due to simple_hash()). + * Ideally, we support sorting of options when generating the ini file. + * + * 4. There is no free() operation. So, memory is freed on netdata exit. + * + * 5. Avoid memory fragmentation + * Since entries are created from multiple threads and a lot of allocations are required + * for each config_option, fragmentation can be a problem for IoT. + * + * 6. Although this way of managing options is quite flexible and dynamic, it wastes memory + * for the names of the options. Since most of the option names are static, we could provide + * a method to allocate only the dynamic option names. + */ + +#ifndef NETDATA_CONFIG_H +#define NETDATA_CONFIG_H 1 + +#include "../libnetdata.h" + +#define CONFIG_FILENAME "netdata.conf" + +#define CONFIG_SECTION_GLOBAL "global" +#define CONFIG_SECTION_WEB "web" +#define CONFIG_SECTION_STATSD "statsd" +#define CONFIG_SECTION_PLUGINS "plugins" +#define CONFIG_SECTION_REGISTRY "registry" +#define CONFIG_SECTION_HEALTH "health" +#define CONFIG_SECTION_BACKEND "backend" +#define CONFIG_SECTION_STREAM "stream" + +// these are used to limit the configuration names and values lengths +// they are not enforced by config.c functions (they will strdup() all strings, no matter of their length) +#define CONFIG_MAX_NAME 1024 +#define CONFIG_MAX_VALUE 2048 + +struct config { + struct section *sections; + netdata_mutex_t mutex; + avl_tree_lock index; +}; + +#define CONFIG_BOOLEAN_INVALID 100 // an invalid value to check for validity (used as default initialization when needed) + +#define CONFIG_BOOLEAN_NO 0 // disabled +#define CONFIG_BOOLEAN_YES 1 // enabled + +#ifndef CONFIG_BOOLEAN_AUTO +#define CONFIG_BOOLEAN_AUTO 2 // enabled if it has useful info when enabled +#endif + +extern int appconfig_load(struct config *root, char *filename, int overwrite_used); + +extern char *appconfig_get(struct config *root, const char *section, const char *name, const char *default_value); +extern long long appconfig_get_number(struct config *root, const char *section, const char *name, long long value); +extern LONG_DOUBLE appconfig_get_float(struct config *root, const char *section, const char *name, LONG_DOUBLE value); +extern int appconfig_get_boolean(struct config *root, const char *section, const char *name, int value); +extern int appconfig_get_boolean_ondemand(struct config *root, const char *section, const char *name, int value); + +extern const char *appconfig_set(struct config *root, const char *section, const char *name, const char *value); +extern const char *appconfig_set_default(struct config *root, const char *section, const char *name, const char *value); +extern long long appconfig_set_number(struct config *root, const char *section, const char *name, long long value); +extern LONG_DOUBLE appconfig_set_float(struct config *root, const char *section, const char *name, LONG_DOUBLE value); +extern int appconfig_set_boolean(struct config *root, const char *section, const char *name, int value); + +extern int appconfig_exists(struct config *root, const char *section, const char *name); +extern int appconfig_move(struct config *root, const char *section_old, const char *name_old, const char *section_new, const char *name_new); + +extern void appconfig_generate(struct config *root, BUFFER *wb, int only_changed); + +extern int appconfig_section_compare(void *a, void *b); + +#endif /* NETDATA_CONFIG_H */ |