gstreamer/ext/alsa/gstalsaclock.c

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/*
* Copyright (C) 2001 CodeFactory AB
* Copyright (C) 2001 Thomas Nyberg <thomas@codefactory.se>
* Copyright (C) 2001-2002 Andy Wingo <apwingo@eos.ncsu.edu>
* Copyright (C) 2003 Benjamin Otte <in7y118@public.uni-hamburg.de>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstalsaclock.h"
/* clock functions */
static void gst_alsa_clock_class_init (gpointer g_class, gpointer class_data);
static void gst_alsa_clock_init (GstAlsaClock * clock);
static GstClockTime gst_alsa_clock_get_internal_time (GstClock * clock);
static guint64 gst_alsa_clock_get_resolution (GstClock * clock);
static GstClockEntryStatus gst_alsa_clock_wait (GstClock * clock,
GstClockEntry * entry);
static void gst_alsa_clock_unlock (GstClock * clock, GstClockEntry * entry);
static GstClockClass *clock_parent_class = NULL;
/* static guint gst_alsa_clock_signals[LAST_SIGNAL] = { 0 }; */
GType
gst_alsa_clock_get_type (void)
{
static GType clock_type = 0;
if (!clock_type) {
static const GTypeInfo clock_info = {
sizeof (GstAlsaClockClass),
NULL,
NULL,
gst_alsa_clock_class_init,
NULL,
NULL,
sizeof (GstAlsaClock),
4,
(GInstanceInitFunc) gst_alsa_clock_init,
NULL
};
clock_type = g_type_register_static (GST_TYPE_CLOCK, "GstAlsaClock",
&clock_info, 0);
}
return clock_type;
}
static void
gst_alsa_clock_class_init (gpointer g_class, gpointer class_data)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
GstClockClass *gstclock_class;
GstAlsaClockClass *klass;
klass = (GstAlsaClockClass *) g_class;
gobject_class = (GObjectClass *) klass;
gstobject_class = (GstObjectClass *) klass;
gstclock_class = (GstClockClass *) klass;
clock_parent_class = g_type_class_ref (GST_TYPE_CLOCK);
gstclock_class->get_internal_time = gst_alsa_clock_get_internal_time;
gstclock_class->get_resolution = gst_alsa_clock_get_resolution;
gstclock_class->wait = gst_alsa_clock_wait;
gstclock_class->unlock = gst_alsa_clock_unlock;
}
static void
gst_alsa_clock_init (GstAlsaClock * clock)
{
gst_object_set_name (GST_OBJECT (clock), "GstAlsaClock");
clock->start_time = GST_CLOCK_TIME_NONE;
}
GstAlsaClock *
gst_alsa_clock_new (gchar * name, GstAlsaClockGetTimeFunc get_time,
GstAlsa * owner)
{
GstAlsaClock *alsa_clock =
GST_ALSA_CLOCK (g_object_new (GST_TYPE_ALSA_CLOCK, NULL));
g_assert (alsa_clock);
alsa_clock->get_time = get_time;
alsa_clock->owner = owner;
alsa_clock->adjust = 0;
gst_object_set_name (GST_OBJECT (alsa_clock), name);
gst_object_set_parent (GST_OBJECT (alsa_clock), GST_OBJECT (owner));
return alsa_clock;
}
void
gst_alsa_clock_start (GstAlsaClock * clock)
{
g_assert (!GST_CLOCK_TIME_IS_VALID (clock->start_time));
if (clock->owner->format) {
clock->start_time = gst_clock_get_event_time (GST_CLOCK (clock))
- clock->get_time (clock->owner);
} else {
clock->start_time = gst_clock_get_event_time (GST_CLOCK (clock));
}
}
void
gst_alsa_clock_stop (GstAlsaClock * clock)
{
GTimeVal timeval;
g_get_current_time (&timeval);
g_assert (GST_CLOCK_TIME_IS_VALID (clock->start_time));
clock->adjust +=
GST_TIMEVAL_TO_TIME (timeval) -
gst_clock_get_event_time (GST_CLOCK (clock));
clock->start_time = GST_CLOCK_TIME_NONE;
}
static GstClockTime
gst_alsa_clock_get_internal_time (GstClock * clock)
{
GstAlsaClock *alsa_clock = GST_ALSA_CLOCK (clock);
if (GST_CLOCK_TIME_IS_VALID (alsa_clock->start_time)) {
return alsa_clock->get_time (alsa_clock->owner) + alsa_clock->start_time;
} else {
GTimeVal timeval;
g_get_current_time (&timeval);
return GST_TIMEVAL_TO_TIME (timeval) + alsa_clock->adjust;
}
}
static guint64
gst_alsa_clock_get_resolution (GstClock * clock)
{
GstAlsaClock *this = GST_ALSA_CLOCK (clock);
if (this->owner->format) {
return GST_SECOND / this->owner->format->rate;
} else {
/* FIXME: is there an "unknown" value? We just return the sysclock's time by default */
return 1 * GST_USECOND;
}
}
static GstClockEntryStatus
gst_alsa_clock_wait (GstClock * clock, GstClockEntry * entry)
{
GstClockTime target, entry_time, glib_start, glib_cur;
GstClockTimeDiff diff;
GstAlsaClock *this = GST_ALSA_CLOCK (clock);
GTimeVal t;
entry_time = gst_alsa_clock_get_internal_time (clock);
diff = GST_CLOCK_ENTRY_TIME (entry) - gst_clock_get_time (clock);
if (diff < 0)
return GST_CLOCK_ENTRY_EARLY;
if (diff > clock->max_diff) {
GST_INFO_OBJECT (this,
"GstAlsaClock: abnormal clock request diff: %" GST_TIME_FORMAT ") >"
" %" GST_TIME_FORMAT, GST_TIME_ARGS (diff),
GST_TIME_ARGS (clock->max_diff));
return GST_CLOCK_ENTRY_EARLY;
}
target = entry_time + diff;
GST_DEBUG_OBJECT (this, "real_target %" GST_TIME_FORMAT
" target %" GST_TIME_FORMAT
" now %" GST_TIME_FORMAT,
GST_TIME_ARGS (target), GST_TIME_ARGS (GST_CLOCK_ENTRY_TIME (entry)),
GST_TIME_ARGS (entry_time));
g_get_current_time (&t);
glib_cur = glib_start = GST_TIMEVAL_TO_TIME (t);
while (gst_alsa_clock_get_internal_time (clock) < target &&
this->last_unlock < entry_time && glib_start + diff * 1.5 > glib_cur) {
g_usleep (gst_alsa_clock_get_resolution (clock) * G_USEC_PER_SEC /
GST_SECOND);
g_get_current_time (&t);
glib_cur = GST_TIMEVAL_TO_TIME (t);
}
return entry->status;
}
static void
gst_alsa_clock_unlock (GstClock * clock, GstClockEntry * entry)
{
GstAlsaClock *this = GST_ALSA_CLOCK (clock);
this->last_unlock = this->get_time (this->owner);
}