src/libnetdata/config/appconfig.h
// 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_DIRECTORIES "directories"
#define CONFIG_SECTION_LOGS "logs"
#define CONFIG_SECTION_ENV_VARS "environment variables"
#define CONFIG_SECTION_SQLITE "sqlite"
#define CONFIG_SECTION_WEB "web"
#define CONFIG_SECTION_WEBRTC "webrtc"
#define CONFIG_SECTION_STATSD "statsd"
#define CONFIG_SECTION_PLUGINS "plugins"
#define CONFIG_SECTION_CLOUD "cloud"
#define CONFIG_SECTION_REGISTRY "registry"
#define CONFIG_SECTION_HEALTH "health"
#define CONFIG_SECTION_STREAM "stream"
#define CONFIG_SECTION_ML "ml"
#define CONFIG_SECTION_EXPORTING "exporting:global"
#define CONFIG_SECTION_PROMETHEUS "prometheus:exporter"
#define CONFIG_SECTION_HOST_LABEL "host labels"
#define EXPORTING_CONF "exporting.conf"
#define CONFIG_SECTION_GLOBAL_STATISTICS "global statistics"
#define CONFIG_SECTION_DB "db"
// 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
// ----------------------------------------------------------------------------
// Config definitions
#define CONFIG_FILE_LINE_MAX ((CONFIG_MAX_NAME + CONFIG_MAX_VALUE + 1024) * 2)
#define CONFIG_VALUE_LOADED 0x01 // has been loaded from the config
#define CONFIG_VALUE_USED 0x02 // has been accessed from the program
#define CONFIG_VALUE_CHANGED 0x04 // has been changed from the loaded value or the internal default value
#define CONFIG_VALUE_CHECKED 0x08 // has been checked if the value is different from the default
struct config_option {
avl_t avl_node; // the index entry of this entry - this has to be first!
uint8_t flags;
uint32_t hash; // a simple hash to speed up searching
// we first compare hashes, and only if the hashes are equal we do string comparisons
char *name;
char *value;
struct config_option *next; // config->mutex protects just this
};
struct section {
avl_t avl_node; // the index entry of this section - this has to be first!
uint32_t hash; // a simple hash to speed up searching
// we first compare hashes, and only if the hashes are equal we do string comparisons
char *name;
struct section *next; // global config_mutex protects just this
struct config_option *values;
avl_tree_lock values_index;
netdata_mutex_t mutex; // this locks only the writers, to ensure atomic updates
// readers are protected using the rwlock in avl_tree_lock
};
struct config {
struct section *first_section;
struct section *last_section; // optimize inserting at the end
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
int appconfig_load(struct config *root, char *filename, int overwrite_used, const char *section_name);
void config_section_wrlock(struct section *co);
void config_section_unlock(struct section *co);
char *appconfig_get_by_section(struct section *co, const char *name, const char *default_value);
char *appconfig_get(struct config *root, const char *section, const char *name, const char *default_value);
long long appconfig_get_number(struct config *root, const char *section, const char *name, long long value);
NETDATA_DOUBLE appconfig_get_float(struct config *root, const char *section, const char *name, NETDATA_DOUBLE value);
int appconfig_get_boolean_by_section(struct section *co, const char *name, int value);
int appconfig_get_boolean(struct config *root, const char *section, const char *name, int value);
int appconfig_get_boolean_ondemand(struct config *root, const char *section, const char *name, int value);
int appconfig_get_duration(struct config *root, const char *section, const char *name, const char *value);
const char *appconfig_set(struct config *root, const char *section, const char *name, const char *value);
const char *appconfig_set_default(struct config *root, const char *section, const char *name, const char *value);
long long appconfig_set_number(struct config *root, const char *section, const char *name, long long value);
NETDATA_DOUBLE appconfig_set_float(struct config *root, const char *section, const char *name, NETDATA_DOUBLE value);
int appconfig_set_boolean(struct config *root, const char *section, const char *name, int value);
int appconfig_exists(struct config *root, const char *section, const char *name);
int appconfig_move(struct config *root, const char *section_old, const char *name_old, const char *section_new, const char *name_new);
void appconfig_generate(struct config *root, BUFFER *wb, int only_changed);
int appconfig_section_compare(void *a, void *b);
void appconfig_section_destroy_non_loaded(struct config *root, const char *section);
void appconfig_section_option_destroy_non_loaded(struct config *root, const char *section, const char *name);
int config_parse_duration(const char* string, int* result);
struct section *appconfig_get_section(struct config *root, const char *name);
void appconfig_wrlock(struct config *root);
void appconfig_unlock(struct config *root);
int appconfig_test_boolean_value(char *s);
struct connector_instance {
char instance_name[CONFIG_MAX_NAME + 1];
char connector_name[CONFIG_MAX_NAME + 1];
};
typedef struct _connector_instance {
struct section *connector; // actual connector
struct section *instance; // This instance
char instance_name[CONFIG_MAX_NAME + 1];
char connector_name[CONFIG_MAX_NAME + 1];
struct _connector_instance *next; // Next instance
} _CONNECTOR_INSTANCE;
_CONNECTOR_INSTANCE *add_connector_instance(struct section *connector, struct section *instance);
#endif /* NETDATA_CONFIG_H */