index 79a171ab16330ed047b2aef2afc043e8217f4d98..6580e90dfcd55a8df4ea52e0ae4ee4ff3ef7d57e 100644 (file)
#include "sysdb.h"
#include "core/object.h"
#include "core/time.h"
+#include "core/timeseries.h"
#include "liboconfig/oconfig.h"
+#include <stdarg.h>
+#include <stdbool.h>
+
#ifdef __cplusplus
extern "C" {
#endif
} sdb_plugin_ctx_t;
#define SDB_PLUGIN_CTX_INIT { 0 }
-struct sdb_plugin_info;
-typedef struct sdb_plugin_info sdb_plugin_info_t;
+typedef struct {
+ char *plugin_name;
+ char *filename;
+
+ /* public attributes */
+ char *description;
+ char *copyright;
+ char *license;
+
+ int version;
+ int plugin_version;
+} sdb_plugin_info_t;
+#define SDB_PLUGIN_INFO_INIT { \
+ /* plugin_name */ NULL, /* filename */ NULL, /* desc */ NULL, \
+ /* copyright */ NULL, /* license */ NULL, \
+ /* version */ -1, /* plugin_version */ -1 }
/* this should be used in the header of a plugin to avoid
* missing prototype warnings/errors for the plugin init
* function */
#define SDB_PLUGIN_MAGIC \
- int sdb_module_init(sdb_plugin_info_t *info);
+ int sdb_module_init(sdb_plugin_info_t *info)
typedef struct {
- _Bool do_loop;
+ bool do_loop;
sdb_time_t default_interval;
} sdb_plugin_loop_t;
#define SDB_PLUGIN_LOOP_INIT { 1, 0 }
/*
* sdb_plugin_load:
* Load (any type of) plugin by loading the shared object file and calling the
- * sdb_module_init function.
+ * sdb_module_init function. If specified, 'plugin_ctx' fine-tunes the
+ * behavior of the plugin. If specified, the plugin will be looked up in
+ * 'basedir', else it defaults to the package libdir.
*/
int
-sdb_plugin_load(const char *name);
+sdb_plugin_load(const char *basedir, const char *name,
+ const sdb_plugin_ctx_t *plugin_ctx);
/*
* sdb_plugin_set_info:
* and also to provide additional information to the user.
*/
enum {
- SDB_PLUGIN_INFO_NAME, /* plugin name: string */
SDB_PLUGIN_INFO_DESC, /* plugin description: string */
SDB_PLUGIN_INFO_COPYRIGHT, /* plugin copyright: string */
SDB_PLUGIN_INFO_LICENSE, /* plugin license: string */
sdb_plugin_set_info(sdb_plugin_info_t *info, int type, ...);
/*
- * plugin callback functions
+ * plugin callback functions:
+ * See the description of the respective register function for what arguments
+ * the callbacks expect.
+ *
+ * The specified name of callback functions is prepended with the plugin name
+ * before being registered with the core.
*/
typedef int (*sdb_plugin_config_cb)(oconfig_item_t *ci);
typedef int (*sdb_plugin_init_cb)(sdb_object_t *user_data);
typedef int (*sdb_plugin_collector_cb)(sdb_object_t *user_data);
+typedef char *(*sdb_plugin_cname_cb)(const char *name,
+ sdb_object_t *user_data);
typedef int (*sdb_plugin_shutdown_cb)(sdb_object_t *user_data);
typedef int (*sdb_plugin_log_cb)(int prio, const char *msg,
sdb_object_t *user_data);
+typedef sdb_timeseries_t *(*sdb_plugin_fetch_ts_cb)(const char *id,
+ sdb_timeseries_opts_t *opts, sdb_object_t *user_data);
+
/*
* sdb_plugin_register_config:
* Register a "config" function. This will be used to pass on the
* - a negative value else
*/
int
-sdb_plugin_register_config(const char *name, sdb_plugin_config_cb callback);
+sdb_plugin_register_config(sdb_plugin_config_cb callback);
/*
* sdb_plugin_register_init:
sdb_plugin_collector_cb callback,
const sdb_time_t *interval, sdb_object_t *user_data);
+/*
+ * sdb_plugin_register_cname:
+ * Register a "cname" (canonicalize name) function. This type of function is
+ * called whenever a host is stored. It accepts the hostname and returns a
+ * canonicalized hostname which will then be used to actually store the host.
+ * If multiple such callbacks are registered, each one of them will be called
+ * in the order they have been registered, each one receiving the result of
+ * the previous callback. If the function returns NULL, the original hostname
+ * is not changed. Any other value has to be dynamically allocated. It will be
+ * freed later on by the core.
+ *
+ * Returns:
+ * - 0 on success
+ * - a negative value else
+ */
+int
+sdb_plugin_register_cname(const char *name, sdb_plugin_cname_cb callback,
+ sdb_object_t *user_data);
+
/*
* sdb_plugin_register_shutdown:
* Register a "shutdown" function to be called after stopping all update
sdb_plugin_register_log(const char *name, sdb_plugin_log_cb callback,
sdb_object_t *user_data);
+/*
+ * sdb_plugin_register_ts_fetcher:
+ * Register a "time-series fetcher" function to be called whenever retrieving
+ * a time-series from a data-store. The callback will receive an identifier
+ * describing where to retrieve the data from (e.g. a filename or some kind of
+ * URL) and options which further describe the query.
+ *
+ * The name is used literally (without prepending the plugin name) to look up
+ * the appropriate fetcher callback.
+ *
+ * Arguments:
+ * - user_data: If specified, this will be passed on to each call of the
+ * callback. The function will take ownership of the object, that is,
+ * increment the reference count by one. In case the caller does not longer
+ * use the object for other purposes, it should thus deref it.
+ */
+int
+sdb_plugin_register_ts_fetcher(const char *name,
+ sdb_plugin_fetch_ts_cb callback, sdb_object_t *user_data);
+
/*
* sdb_plugin_get_ctx, sdb_plugin_set_ctx:
* The plugin context defines a set of settings that are available whenever a
* plugin has been called. It may be used to pass around various information
* between the different component of the library without having each and
* every plugin care about it.
+ *
+ * If non-NULL, sdb_plugin_set_ctx stores the previous context in the location
+ * pointed to by 'old'.
*/
sdb_plugin_ctx_t
sdb_plugin_get_ctx(void);
-sdb_plugin_ctx_t
-sdb_plugin_set_ctx(sdb_plugin_ctx_t ctx);
+int
+sdb_plugin_set_ctx(sdb_plugin_ctx_t ctx, sdb_plugin_ctx_t *old);
+
+/*
+ * sdb_plugin_current:
+ * Retrieve information about the plugin (if any) from which the current call
+ * into the core originated. The return value may not be modified.
+ *
+ * Returns:
+ * - information about the current plugin if we were called from some
+ * plugin's callback function
+ * - NULL else
+ */
+const sdb_plugin_info_t *
+sdb_plugin_current(void);
/*
* sdb_plugin_configure:
- * Configure the plugin called 'name' (according to the registered config
- * callback) using the config tree 'ci'.
+ * Configure the plugin called 'name' using the config tree 'ci'. The plugin
+ * name is the same as the one used when loading the plugin.
*
* Returns:
* - 0 on success
int
sdb_plugin_configure(const char *name, oconfig_item_t *ci);
+/*
+ * sdb_plugin_reconfigure_init, sdb_plugin_reconfigure_finish:
+ * Reconfigure all plugins. This happens in multiple steps: first, call
+ * sdb_plugin_reconfigure_init to deconfigure all plugins by calling their
+ * config callbacks with a NULL config tree and unregistering all callbacks.
+ * Then, sdb_plugin_configure and other functions may be used to provide the
+ * new configuration or load new plugins. For all plugins which were already
+ * loaded before, sdb_module_init will be called with a NULL argument when
+ * reloading them.
+ * Finally, sdb_plugin_reconfigure_finish will clean up leftover pieces, like
+ * unloading plugins which are no longer in use.
+ *
+ * Returns:
+ * - 0 on success
+ * - a negative value else
+ */
+int
+sdb_plugin_reconfigure_init(void);
+int
+sdb_plugin_reconfigure_finish(void);
+
/*
* sdb_plugin_init_all:
* Initialize all plugins using their registered "init" function.
+ *
+ * Returns:
+ * The number of failed initializations.
*/
int
sdb_plugin_init_all(void);
+/*
+ * sdb_plugin_shutdown_all:
+ * Shutdown all plugins using their registered "shutdown" function.
+ *
+ * Returns:
+ * The number of failed shutdowns.
+ */
+int
+sdb_plugin_shutdown_all(void);
+
/*
* sdb_plugin_collector_loop:
* Loop until loop->do_loop is false, calling the next collector function on
int
sdb_plugin_collector_loop(sdb_plugin_loop_t *loop);
+/*
+ * sdb_plugin_cname:
+ * Returns the canonicalized hostname. The given hostname argument has to
+ * point to dynamically allocated memory and might be freed by the function.
+ * The return value will also be dynamically allocated (but it might be
+ * unchanged) and has to be freed by the caller.
+ */
+char *
+sdb_plugin_cname(char *hostname);
+
/*
* sdb_plugin_log:
* Log the specified message using all registered log callbacks. The message
int
sdb_plugin_log(int prio, const char *msg);
+/*
+ * sdb_plugin_logf:
+ * Log a formatted message. See sdb_plugin_log for more information.
+ */
+int
+sdb_plugin_vlogf(int prio, const char *fmt, va_list ap)
+ __attribute__((format(printf, 2, 0)));
+int
+sdb_plugin_logf(int prio, const char *fmt, ...)
+ __attribute__((format(printf, 2, 3)));
+
+/*
+ * sdb_plugin_fetch_timeseries:
+ * Fetch the time-series identified by 'id' from a backend data-store of the
+ * specified 'type'. The type has to match an existing time-series fetcher
+ * callback's name. The identifier is passed through to the callback which
+ * then needs to make sense of it. The time-series option specify which data
+ * to fetch.
+ *
+ * Returns:
+ * - a time-series on success
+ * - NULL else
+ */
+sdb_timeseries_t *
+sdb_plugin_fetch_timeseries(const char *type, const char *id,
+ sdb_timeseries_opts_t *opts);
+
#ifdef __cplusplus
} /* extern "C" */
#endif