@ -25,6 +25,7 @@
*
* \ arg \ ref AstExtState
*/
/*! \page AstExtState Extension and device states in Asterisk
*
* Asterisk has an internal system that reports states
@ -166,6 +167,17 @@ static pthread_t change_thread = AST_PTHREADT_NULL;
/*! \brief Flag for the queue */
static ast_cond_t change_pending ;
/*! \brief Whether or not to cache this device state value */
enum devstate_cache {
/*! Cache this value as it is coming from a device state provider which is
* pushing up state change events to us as they happen */
CACHE_ON ,
/*! Don't cache this result, since it was pulled from the device state provider.
* We only want to cache results from device state providers that are being nice
* and pushing state change events up to us as they happen . */
CACHE_OFF ,
} ;
/* Forward declarations */
static int getproviderstate ( const char * provider , const char * address ) ;
@ -261,18 +273,42 @@ enum ast_device_state ast_parse_device_state(const char *device)
return res ;
}
static enum ast_device_state devstate_cached ( const char * device )
{
enum ast_device_state res = AST_DEVICE_UNKNOWN ;
struct ast_event * event ;
event = ast_event_get_cached ( AST_EVENT_DEVICE_STATE ,
AST_EVENT_IE_DEVICE , AST_EVENT_IE_PLTYPE_STR , device ,
AST_EVENT_IE_END ) ;
if ( ! event )
return res ;
res = ast_event_get_ie_uint ( event , AST_EVENT_IE_STATE ) ;
ast_event_destroy ( event ) ;
return res ;
}
/*! \brief Check device state through channel specific function or generic function */
enum ast_device_state ast_device_state ( const char * device )
{
char * buf ;
char * number ;
const struct ast_channel_tech * chan_tech ;
enum ast_device_state res = AST_DEVICE_UNKNOWN ;
enum ast_device_state res ;
/*! \brief Channel driver that provides device state */
char * tech ;
/*! \brief Another provider of device state */
char * provider = NULL ;
/* If the last known state is cached, just return that */
res = devstate_cached ( device ) ;
if ( res ! = AST_DEVICE_UNKNOWN )
return res ;
buf = ast_strdupa ( device ) ;
tech = strsep ( & buf , " / " ) ;
if ( ! ( number = buf ) ) {
@ -368,17 +404,10 @@ static int getproviderstate(const char *provider, const char *address)
return res ;
}
/*! \brief Notify callback watchers of change, and notify PBX core for hint updates
Normally executed within a separate thread
*/
static void do_state_change ( const char * device )
static void devstate_event ( const char * device , enum ast_device_state state , enum devstate_cache cache )
{
enum ast_device_state state ;
struct ast_event * event ;
state = ast_device_state ( device ) ;
ast_debug ( 3 , " Changing state for %s - state %d (%s) \n " , device , state , devstate2str ( state ) ) ;
if ( ! ( event = ast_event_new ( AST_EVENT_DEVICE_STATE ,
AST_EVENT_IE_DEVICE , AST_EVENT_IE_PLTYPE_STR , device ,
AST_EVENT_IE_STATE , AST_EVENT_IE_PLTYPE_UINT , state ,
@ -386,12 +415,31 @@ static void do_state_change(const char *device)
return ;
}
if ( cache = = CACHE_ON ) {
/* Cache this event, replacing an event in the cache with the same
* device name if it exists . */
ast_event_queue_and_cache ( event ,
AST_EVENT_IE_DEVICE , AST_EVENT_IE_PLTYPE_STR ,
AST_EVENT_IE_END ) ;
} else {
ast_event_queue ( event ) ;
}
}
static int __ast_device_state_changed_literal ( char * buf )
/*! Called by the state change thread to find out what the state is, and then
* to queue up the state change event */
static void do_state_change ( const char * device )
{
enum ast_device_state state ;
state = ast_device_state ( device ) ;
ast_debug ( 3 , " Changing state for %s - state %d (%s) \n " , device , state , devstate2str ( state ) ) ;
devstate_event ( device , state , CACHE_OFF ) ;
}
static int __ast_devstate_changed_literal ( enum ast_device_state state , char * buf )
{
char * device ;
struct state_change * change ;
@ -405,7 +453,9 @@ static int __ast_device_state_changed_literal(char *buf)
if ( tmp )
* tmp = ' \0 ' ;
if ( change_thread = = AST_PTHREADT_NULL | | ! ( change = ast_calloc ( 1 , sizeof ( * change ) + strlen ( device ) ) ) ) {
if ( state ! = AST_DEVICE_UNKNOWN ) {
devstate_event ( device , state , CACHE_ON ) ;
} else if ( change_thread = = AST_PTHREADT_NULL | | ! ( change = ast_calloc ( 1 , sizeof ( * change ) + strlen ( device ) ) ) ) {
/* we could not allocate a change struct, or */
/* there is no background thread, so process the change now */
do_state_change ( device ) ;
@ -421,11 +471,34 @@ static int __ast_device_state_changed_literal(char *buf)
return 1 ;
}
int ast_devstate_changed_literal ( enum ast_device_state state , const char * dev )
{
char * buf ;
buf = ast_strdupa ( dev ) ;
return __ast_devstate_changed_literal ( state , buf ) ;
}
int ast_device_state_changed_literal ( const char * dev )
{
char * buf ;
buf = ast_strdupa ( dev ) ;
return __ast_device_state_changed_literal ( buf ) ;
return __ast_devstate_changed_literal ( AST_DEVICE_UNKNOWN , buf ) ;
}
int ast_devstate_changed ( enum ast_device_state state , const char * fmt , . . . )
{
char buf [ AST_MAX_EXTENSION ] ;
va_list ap ;
va_start ( ap , fmt ) ;
vsnprintf ( buf , sizeof ( buf ) , fmt , ap ) ;
va_end ( ap ) ;
return __ast_devstate_changed_literal ( state , buf ) ;
}
/*! \brief Accept change notification, add it to change queue */
@ -437,7 +510,8 @@ int ast_device_state_changed(const char *fmt, ...)
va_start ( ap , fmt ) ;
vsnprintf ( buf , sizeof ( buf ) , fmt , ap ) ;
va_end ( ap ) ;
return __ast_device_state_changed_literal ( buf ) ;
return __ast_devstate_changed_literal ( AST_DEVICE_UNKNOWN , buf ) ;
}
/*! \brief Go through the dev state change queue and update changes in the dev state thread */
Russell Bryant
18 years ago