Services API. More...

#include <glib.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdbool.h>
#include <sys/types.h>
#include <crm_config.h>
#include <crm/common/agents.h>
#include <crm/common/results.h>
#include <crm/services_compat.h>

Include dependency graph for services.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	svc_action_s
	Object for executing external actions. More...

Macros
#define	SYSTEMCTL "/bin/systemctl"

#define	PCMK_OCF_REASON_PREFIX "ocf-exit-reason:"

#define	PCMK_DEFAULT_AGENT_VERSION "0.1"

Typedefs
typedef struct svc_action_private_s	svc_action_private_t

typedef struct svc_action_s	svc_action_t
	Object for executing external actions. More...

Enumerations
enum	lsb_exitcode { PCMK_LSB_OK = 0, PCMK_LSB_UNKNOWN_ERROR = 1, PCMK_LSB_INVALID_PARAM = 2, PCMK_LSB_UNIMPLEMENT_FEATURE = 3, PCMK_LSB_INSUFFICIENT_PRIV = 4, PCMK_LSB_NOT_INSTALLED = 5, PCMK_LSB_NOT_CONFIGURED = 6, PCMK_LSB_NOT_RUNNING = 7 }

enum	lsb_status_exitcode { PCMK_LSB_STATUS_OK = 0, PCMK_LSB_STATUS_VAR_PID = 1, PCMK_LSB_STATUS_VAR_LOCK = 2, PCMK_LSB_STATUS_NOT_RUNNING = 3, PCMK_LSB_STATUS_UNKNOWN = 4, PCMK_LSB_STATUS_NOT_INSTALLED = 150, PCMK_LSB_STATUS_INSUFFICIENT_PRIV = 151 }

enum	svc_action_flags { SVC_ACTION_LEAVE_GROUP = 0x01, SVC_ACTION_NON_BLOCKED = 0x02 }

Functions
GList *	get_directory_list (const char *root, gboolean files, gboolean executable)
	Get a list of files or directories in a given path. More...

GList *	resources_list_providers (const char *standard)
	Get a list of providers. More...

GList *	resources_list_agents (const char standard, const char provider)
	Get a list of resource agents. More...

GList *	resources_list_standards (void)

gboolean	resources_agent_exists (const char standard, const char provider, const char *agent)
	Check whether a resource agent exists on the local host. More...

svc_action_t *	resources_action_create (const char name, const char standard, const char provider, const char agent, const char action, guint interval_ms, int timeout, GHashTable params, enum svc_action_flags flags)
	Create a new resource action. More...

gboolean	services_action_kick (const char name, const char action, guint interval_ms)
	Reschedule a recurring action for immediate execution. More...

const char *	resources_find_service_class (const char *agent)
	Find first service class that can provide a specified agent. More...

svc_action_t *	services_action_create_generic (const char exec, const char args[])
	Request execution of an arbitrary command. More...

void	services_action_cleanup (svc_action_t *op)

void	services_action_free (svc_action_t *op)

int	services_action_user (svc_action_t op, const char user)
	Set the user and group that an action will execute as. More...

gboolean	services_action_sync (svc_action_t *op)

gboolean	services_action_async_fork_notify (svc_action_t op, void(action_callback)(svc_action_t ), void(action_fork_callback)(svc_action_t *))
	Run an action asynchronously, with callback after process is forked. More...

gboolean	services_action_async (svc_action_t op, void(action_callback)(svc_action_t *))
	Request asynchronous execution of an action. More...

gboolean	services_action_cancel (const char name, const char action, guint interval_ms)
	Cancel a recurring action. More...

svc_action_t *	services_alert_create (const char id, const char exec, int timeout, GHashTable params, int sequence, void cb_data)
	Create an alert agent action. More...

gboolean	services_alert_async (svc_action_t action, void(cb)(svc_action_t *op))
	Execute an alert agent action. More...

enum ocf_exitcode	services_result2ocf (const char standard, const char action, int exit_status)

Detailed Description

Services API.

Definition in file services.h.

Macro Definition Documentation

◆ PCMK_DEFAULT_AGENT_VERSION

#define PCMK_DEFAULT_AGENT_VERSION "0.1"

Definition at line 49 of file services.h.

◆ PCMK_OCF_REASON_PREFIX

#define PCMK_OCF_REASON_PREFIX "ocf-exit-reason:"

Definition at line 46 of file services.h.

◆ SYSTEMCTL

#define SYSTEMCTL "/bin/systemctl"

Definition at line 39 of file services.h.

Typedef Documentation

◆ svc_action_private_t

typedef struct svc_action_private_s svc_action_private_t

Definition at line 84 of file services.h.

◆ svc_action_t

typedef struct svc_action_s svc_action_t

Object for executing external actions.

Note: This object should never be instantiated directly, but instead created using one of the constructor functions (resources_action_create() for resource agents, services_alert_create() for alert agents, or services_action_create_generic() for generic executables). Similarly, do not use sizeof() on this struct.

Enumeration Type Documentation

◆ lsb_exitcode

enum lsb_exitcode

Enumerator
PCMK_LSB_OK
PCMK_LSB_UNKNOWN_ERROR
PCMK_LSB_INVALID_PARAM
PCMK_LSB_UNIMPLEMENT_FEATURE
PCMK_LSB_INSUFFICIENT_PRIV
PCMK_LSB_NOT_INSTALLED
PCMK_LSB_NOT_CONFIGURED
PCMK_LSB_NOT_RUNNING

Definition at line 51 of file services.h.

◆ lsb_status_exitcode

enum lsb_status_exitcode

Enumerator
PCMK_LSB_STATUS_OK
PCMK_LSB_STATUS_VAR_PID
PCMK_LSB_STATUS_VAR_LOCK
PCMK_LSB_STATUS_NOT_RUNNING
PCMK_LSB_STATUS_UNKNOWN
PCMK_LSB_STATUS_NOT_INSTALLED
PCMK_LSB_STATUS_INSUFFICIENT_PRIV

Definition at line 66 of file services.h.

◆ svc_action_flags

enum svc_action_flags

Enumerator
SVC_ACTION_LEAVE_GROUP
SVC_ACTION_NON_BLOCKED

Definition at line 78 of file services.h.

Function Documentation

◆ get_directory_list()

GList* get_directory_list	(	const char *	root,
		gboolean	files,
		gboolean	executable
	)

Get a list of files or directories in a given path.

Parameters

[in]	root	Full path to a directory to read
[in]	files	Return list of files if TRUE or directories if FALSE
[in]	executable	If TRUE and files is TRUE, only return executable files

Returns: List of what was found as char * items.

Note: The caller is responsibile for freeing the result with g_list_free_full(list, free).

Definition at line 1025 of file services.c.

◆ resources_action_create()

svc_action_t* resources_action_create	(	const char *	name,
		const char *	standard,
		const char *	provider,
		const char *	agent,
		const char *	action,
		guint	interval_ms,
		int	timeout,
		GHashTable *	params,
		enum svc_action_flags	flags
	)

Create a new resource action.

Parameters

[in]	name	Name of resource that action is for
[in]	standard	Resource agent standard
[in]	provider	Resource agent provider
[in]	agent	Resource agent name
[in]	action	Name of action to create
[in]	interval_ms	How often to repeat action (if 0, execute once)
[in]	timeout	Error if not complete within this time (ms)
[in,out]	params	Action parameters
[in]	flags	Group of enum svc_action_flags

Returns: Newly allocated action

Note: This function assumes ownership of (and may free) params.; The caller is responsible for freeing the return value using services_action_free().

Definition at line 328 of file services.c.

◆ resources_agent_exists()

gboolean resources_agent_exists	(	const char *	standard,
		const char *	provider,
		const char *	agent
	)

Check whether a resource agent exists on the local host.

Parameters

[in]	standard	Resource agent standard of agent to check
[in]	provider	Provider of agent to check (or NULL)
[in]	agent	Name of agent to check

Returns: TRUE if agent exists locally, otherwise FALSE

Definition at line 1121 of file services.c.

◆ resources_find_service_class()

const char* resources_find_service_class ( const char * agent )

Find first service class that can provide a specified agent.

Parameters

[in] agent Name of agent to search for

Returns: Service class if found, NULL otherwise

Note: The priority is LSB then systemd. It would be preferable to put systemd first, but LSB merely requires a file existence check, while systemd requires contacting DBus.

Definition at line 63 of file services.c.

◆ resources_list_agents()

GList* resources_list_agents	(	const char *	standard,
		const char *	provider
	)

Get a list of resource agents.

Parameters

[in]	standard	List agents of this standard (or NULL for all)
[in]	provider	List agents of this provider (or NULL for all)

Returns: List of resource agents as char * items.

Note: The caller is responsible for freeing the result using g_list_free_full(list, free).

Definition at line 1071 of file services.c.

◆ resources_list_providers()

GList* resources_list_providers ( const char * standard )

Get a list of providers.

Parameters

[in] standard List providers of this resource agent standard

Returns: List of providers as char * list items (or NULL if standard does not support providers)

Note: The caller is responsible for freeing the result using g_list_free_full(list, free).

Definition at line 1061 of file services.c.

◆ resources_list_standards()

GList* resources_list_standards ( void )

Get list of available standards

Returns: List of resource standards as char * items.

Note: The caller is responsible for freeing the result using g_list_free_full(list, free).

Definition at line 1031 of file services.c.

◆ services_action_async()

gboolean services_action_async	(	svc_action_t *	op,
		void()(svc_action_t )	action_callback
	)

Request asynchronous execution of an action.

Parameters

[in,out]	op	Action to execute
[in]	action_callback	Function to call when the action completes (if NULL, any previously set callback will continue to be used)

Return values

TRUE	if the caller should not free or otherwise use `op` again, because one of these conditions is true:

op is NULL.
The action was successfully initiated, in which case action_callback has not been called (it will be called when the action completes).
The action's ID matched an existing recurring action. The existing action has taken over the callback and callback data from op and has been re-initiated asynchronously, and op has been freed.
Another action for the same resource is in flight, and op will be blocked until it completes.
The action could not be initiated, and is either non-recurring or being cancelled. action_callback has been called, and op has been freed.

Return values

FALSE if is still valid, because the action cannot be initiated, and is a recurring action that is not being cancelled. action_callback has been called, and a timer has been set for the next invocation of op.

Definition at line 874 of file services.c.

◆ services_action_async_fork_notify()

gboolean services_action_async_fork_notify	(	svc_action_t *	op,
		void()(svc_action_t )	action_callback,
		void()(svc_action_t )	action_fork_callback
	)

Run an action asynchronously, with callback after process is forked.

Parameters

[in,out]	op	Action to run
[in]	action_callback	Function to call when action completes (if NULL, any previously set callback will continue to be used)
[in]	action_fork_callback	Function to call after child process is forked for action (if NULL, any previously set callback will continue to be used)

Return values

TRUE	if the caller should not free or otherwise use `op` again, because one of these conditions is true:

op is NULL.
The action was successfully initiated, in which case action_fork_callback has been called, but action_callback has not (it will be called when the action completes).
The action's ID matched an existing recurring action. The existing action has taken over the callback and callback data from op and has been re-initiated asynchronously, and op has been freed.
Another action for the same resource is in flight, and op will be blocked until it completes.
The action could not be initiated, and is either non-recurring or being cancelled. action_fork_callback has not been called, but action_callback has, and op has been freed.

Return values

FALSE if is still valid, because the action cannot be initiated, and is a recurring action that is not being cancelled. action_fork_callback has not been called, but action_callback has, and a timer has been set for the next invocation of op.

Definition at line 840 of file services.c.

◆ services_action_cancel()

gboolean services_action_cancel	(	const char *	name,
		const char *	action,
		guint	interval_ms
	)

Cancel a recurring action.

Parameters

[in]	name	Name of resource that operation is for
[in]	action	Name of operation to cancel
[in]	interval_ms	Interval of operation to cancel

Returns: TRUE if action was successfully cancelled, FALSE otherwise

Definition at line 644 of file services.c.

◆ services_action_cleanup()

void services_action_cleanup ( svc_action_t * op )

Definition at line 491 of file services.c.

◆ services_action_create_generic()

svc_action_t* services_action_create_generic	(	const char *	exec,
		const char *	args[]
	)

Request execution of an arbitrary command.

This API has useful infrastructure in place to be able to run a command in the background and get notified via a callback when the command finishes.

Parameters

[in]	exec	Full path to command executable
[in]	args	NULL-terminated list of arguments to pass to command

Returns: Newly allocated action object

Definition at line 349 of file services.c.

◆ services_action_free()

void services_action_free ( svc_action_t * op )

Definition at line 565 of file services.c.

◆ services_action_kick()

gboolean services_action_kick	(	const char *	name,
		const char *	action,
		guint	interval_ms
	)

Reschedule a recurring action for immediate execution.

Parameters

[in]	name	Name of resource that action is for
[in]	action	Action's name
[in]	interval_ms	Action's interval (in milliseconds)

Returns: TRUE on success, otherwise FALSE

Definition at line 712 of file services.c.

◆ services_action_sync()

gboolean services_action_sync ( svc_action_t * op )

Definition at line 990 of file services.c.

◆ services_action_user()

int services_action_user	(	svc_action_t *	op,
		const char *	user
	)

Set the user and group that an action will execute as.

Parameters

[in,out]	op	Action to modify
[in]	user	Name of user to execute action as
[in]	group	Name of group to execute action as

Returns: pcmk_ok on success, -errno otherwise

Note: This will have no effect unless the process executing the action runs as root and the action is not a systemd action. We could implement this for systemd by adding User= and Group= to [Service] in the override file, but that seems more likely to cause problems than be useful.

Definition at line 435 of file services.c.

◆ services_alert_async()

gboolean services_alert_async	(	svc_action_t *	action,
		void()(svc_action_t op)	cb
	)

Execute an alert agent action.

Parameters

[in,out]	action	Action to execute
[in]	cb	Function to call when action completes

Returns: TRUE if the library will free action, FALSE otherwise

Note: If this function returns FALSE, it is the caller's responsibility to free the action with services_action_free(). However, unless someone intentionally creates a recurring alert action, this will never return FALSE.

Definition at line 455 of file services.c.

◆ services_alert_create()

svc_action_t* services_alert_create	(	const char *	id,
		const char *	exec,
		int	timeout,
		GHashTable *	params,
		int	sequence,
		void *	cb_data
	)

Create an alert agent action.

Parameters

[in]	id	Alert ID
[in]	exec	Path to alert agent executable
[in]	timeout	Action timeout
[in]	params	Parameters to use with action
[in]	sequence	Action sequence number
[in]	cb_data	Data to pass to callback function

Returns: New action on success, NULL on error

Note: It is the caller's responsibility to free cb_data. The caller should not free params explicitly.

Definition at line 406 of file services.c.

◆ services_result2ocf()

enum ocf_exitcode services_result2ocf	(	const char *	standard,
		const char *	action,
		int	exit_status
	)

Definition at line 540 of file services.c.

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ PCMK_DEFAULT_AGENT_VERSION

◆ PCMK_OCF_REASON_PREFIX

◆ SYSTEMCTL

Typedef Documentation

◆ svc_action_private_t

◆ svc_action_t

Enumeration Type Documentation

◆ lsb_exitcode

◆ lsb_status_exitcode

◆ svc_action_flags

Function Documentation

◆ get_directory_list()

◆ resources_action_create()

◆ resources_agent_exists()

◆ resources_find_service_class()

◆ resources_list_agents()

◆ resources_list_providers()

◆ resources_list_standards()

◆ services_action_async()

◆ services_action_async_fork_notify()

◆ services_action_cancel()

◆ services_action_cleanup()

◆ services_action_create_generic()

◆ services_action_free()

◆ services_action_kick()

◆ services_action_sync()

◆ services_action_user()

◆ services_alert_async()

◆ services_alert_create()

◆ services_result2ocf()