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#include "services/clock-service.h"
//
// FoobarClockService:
//
// Service providing an auto-updating timestamp value which can be used to display the current time.
//
struct _FoobarClockService
{
GObject parent_instance;
GDateTime* time;
guint source_id;
};
enum
{
PROP_TIME = 1,
N_PROPS,
};
static GParamSpec* props[N_PROPS] = { 0 };
static void foobar_clock_service_class_init ( FoobarClockServiceClass* klass );
static void foobar_clock_service_init ( FoobarClockService* self );
static void foobar_clock_service_get_property( GObject* object,
guint prop_id,
GValue* value,
GParamSpec* pspec );
static void foobar_clock_service_finalize ( GObject* object );
static gboolean foobar_clock_service_handle_tick ( gpointer userdata );
G_DEFINE_FINAL_TYPE( FoobarClockService, foobar_clock_service, G_TYPE_OBJECT )
// ---------------------------------------------------------------------------------------------------------------------
// Service Implementation
// ---------------------------------------------------------------------------------------------------------------------
//
// Static initialization for the clock service.
//
void foobar_clock_service_class_init( FoobarClockServiceClass* klass )
{
GObjectClass* object_klass = G_OBJECT_CLASS( klass );
object_klass->get_property = foobar_clock_service_get_property;
object_klass->finalize = foobar_clock_service_finalize;
props[PROP_TIME] = g_param_spec_boxed(
"time",
"Time",
"The current time, regularly updated.",
G_TYPE_DATE_TIME,
G_PARAM_READABLE );
g_object_class_install_properties( object_klass, N_PROPS, props );
}
//
// Instance initialization for the clock service.
//
void foobar_clock_service_init( FoobarClockService* self )
{
self->time = g_date_time_new_now_local( );
self->source_id = g_timeout_add_seconds( 1, foobar_clock_service_handle_tick, self );
}
//
// Property getter implementation, mapping a property id to a method.
//
void foobar_clock_service_get_property(
GObject* object,
guint prop_id,
GValue* value,
GParamSpec* pspec )
{
FoobarClockService* self = (FoobarClockService*)object;
switch ( prop_id )
{
case PROP_TIME:
g_value_set_boxed( value, foobar_clock_service_get_time( self ) );
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID( object, prop_id, pspec );
break;
}
}
//
// Instance cleanup for the clock service.
//
void foobar_clock_service_finalize( GObject* object )
{
FoobarClockService* self = (FoobarClockService*)object;
g_clear_pointer( &self->time, g_date_time_unref );
g_clear_handle_id( &self->source_id, g_source_remove );
G_OBJECT_CLASS( foobar_clock_service_parent_class )->finalize( object );
}
// ---------------------------------------------------------------------------------------------------------------------
// Public API
// ---------------------------------------------------------------------------------------------------------------------
//
// Create a new clock service instance.
//
FoobarClockService* foobar_clock_service_new( void )
{
return g_object_new( FOOBAR_TYPE_CLOCK_SERVICE, NULL );
}
//
// Get the current snapshot of the timestamp.
//
// This may be a bit older than the value returned by g_date_time_new_now_local.
//
GDateTime* foobar_clock_service_get_time( FoobarClockService* self )
{
g_return_val_if_fail( FOOBAR_IS_CLOCK_SERVICE( self ), NULL );
return self->time;
}
// ---------------------------------------------------------------------------------------------------------------------
// Signal Handlers
// ---------------------------------------------------------------------------------------------------------------------
//
// Called every time the update delay has elapsed to update the current timestamp value.
//
gboolean foobar_clock_service_handle_tick( gpointer userdata )
{
FoobarClockService* self = (FoobarClockService*)userdata;
g_clear_pointer( &self->time, g_date_time_unref );
self->time = g_date_time_new_now_local( );
g_object_notify_by_pspec( G_OBJECT( self ), props[PROP_TIME] );
return G_SOURCE_CONTINUE;
}
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