sys/v4l2/gstv4l2element.c

/* G-Streamer generic V4L2 element
 * Copyright (C) 2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>

#include "v4l2_calls.h"
#include "gstv4l2tuner.h"
#include "gstv4l2xoverlay.h"
#include "gstv4l2colorbalance.h"

#include <gst/propertyprobe/propertyprobe.h>

/* elementfactory details */
static GstElementDetails gst_v4l2element_details = {
  "Generic video4linux2 Element",
  "Generic/Video",
  "Generic plugin for handling common video4linux2 calls",
  "Ronald Bultje <rbultje@ronald.bitfreak.net>"
};

/* V4l2Element signals and args */
enum
{
  /* FILL ME */
  SIGNAL_OPEN,
  SIGNAL_CLOSE,
  LAST_SIGNAL
};

enum
{
  ARG_0,
  ARG_DEVICE,
  ARG_DEVICE_NAME,
  ARG_NORM,
  ARG_CHANNEL,
  ARG_FREQUENCY,
  ARG_FLAGS
};


static void gst_v4l2element_class_init (GstV4l2ElementClass * klass);
static void gst_v4l2element_base_init (GstV4l2ElementClass * klass);
static void gst_v4l2element_init (GstV4l2Element * v4lelement);
static void gst_v4l2element_dispose (GObject * object);
static void gst_v4l2element_set_property (GObject * object,
    guint prop_id, const GValue * value, GParamSpec * pspec);
static void gst_v4l2element_get_property (GObject * object,
    guint prop_id, GValue * value, GParamSpec * pspec);
static GstElementStateReturn
gst_v4l2element_change_state (GstElement * element);


static GstElementClass *parent_class = NULL;
static guint gst_v4l2element_signals[LAST_SIGNAL] = { 0 };


static gboolean
gst_v4l2_iface_supported (GstImplementsInterface * iface, GType iface_type)
{
  GstV4l2Element *v4l2element = GST_V4L2ELEMENT (iface);

  g_assert (iface_type == GST_TYPE_TUNER ||
      iface_type == GST_TYPE_X_OVERLAY || iface_type == GST_TYPE_COLOR_BALANCE);

  if (v4l2element->video_fd == -1)
    return FALSE;

  if (iface_type == GST_TYPE_X_OVERLAY && !GST_V4L2_IS_OVERLAY (v4l2element))
    return FALSE;

  return TRUE;
}


static void
gst_v4l2_interface_init (GstImplementsInterfaceClass * klass)
{
  /* default virtual functions */
  klass->supported = gst_v4l2_iface_supported;
}


static const GList *
gst_v4l2_probe_get_properties (GstPropertyProbe * probe)
{
  GObjectClass *klass = G_OBJECT_GET_CLASS (probe);
  static GList *list = NULL;

  if (!list) {
    list = g_list_append (NULL, g_object_class_find_property (klass, "device"));
  }

  return list;
}

static gboolean
gst_v4l2_class_probe_devices (GstV4l2ElementClass * klass, gboolean check)
{
  static gboolean init = FALSE;
  static GList *devices = NULL;

  if (!init && !check) {
    gchar *dev_base[] = { "/dev/video", "/dev/v4l/video", NULL };
    gint base, n, fd;

    while (devices) {
      GList *item = devices;
      gchar *device = item->data;

      devices = g_list_remove (devices, item);
      g_free (device);
    }

    /* detect /dev entries */
    for (n = 0; n < 64; n++) {
      for (base = 0; dev_base[base] != NULL; base++) {
	struct stat s;
	gchar *device = g_strdup_printf ("%s%d",
	    dev_base[base], n);

	/* does the /dev/ entry exist at all? */
	if (stat (device, &s) == 0) {
	  /* yes: is a device attached? */
	  if ((fd = open (device, O_RDONLY)) > 0 || errno == EBUSY) {
	    if (fd > 0)
	      close (fd);

	    devices = g_list_append (devices, device);
	    break;
	  }
	}
	g_free (device);
      }
    }

    init = TRUE;
  }

  klass->devices = devices;

  return init;
}

static void
gst_v4l2_probe_probe_property (GstPropertyProbe * probe,
    guint prop_id, const GParamSpec * pspec)
{
  GstV4l2ElementClass *klass = GST_V4L2ELEMENT_GET_CLASS (probe);

  switch (prop_id) {
    case ARG_DEVICE:
      gst_v4l2_class_probe_devices (klass, FALSE);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (probe, prop_id, pspec);
      break;
  }
}

static gboolean
gst_v4l2_probe_needs_probe (GstPropertyProbe * probe,
    guint prop_id, const GParamSpec * pspec)
{
  GstV4l2ElementClass *klass = GST_V4L2ELEMENT_GET_CLASS (probe);
  gboolean ret = FALSE;

  switch (prop_id) {
    case ARG_DEVICE:
      ret = !gst_v4l2_class_probe_devices (klass, TRUE);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (probe, prop_id, pspec);
      break;
  }

  return ret;
}

static GValueArray *
gst_v4l2_class_list_devices (GstV4l2ElementClass * klass)
{
  GValueArray *array;
  GValue value = { 0 };
  GList *item;

  if (!klass->devices)
    return NULL;

  array = g_value_array_new (g_list_length (klass->devices));
  item = klass->devices;
  g_value_init (&value, G_TYPE_STRING);
  while (item) {
    gchar *device = item->data;

    g_value_set_string (&value, device);
    g_value_array_append (array, &value);

    item = item->next;
  }
  g_value_unset (&value);

  return array;
}

static GValueArray *
gst_v4l2_probe_get_values (GstPropertyProbe * probe,
    guint prop_id, const GParamSpec * pspec)
{
  GstV4l2ElementClass *klass = GST_V4L2ELEMENT_GET_CLASS (probe);
  GValueArray *array = NULL;

  switch (prop_id) {
    case ARG_DEVICE:
      array = gst_v4l2_class_list_devices (klass);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (probe, prop_id, pspec);
      break;
  }

  return array;
}


static void
gst_v4l2_property_probe_interface_init (GstPropertyProbeInterface * iface)
{
  iface->get_properties = gst_v4l2_probe_get_properties;
  iface->probe_property = gst_v4l2_probe_probe_property;
  iface->needs_probe = gst_v4l2_probe_needs_probe;
  iface->get_values = gst_v4l2_probe_get_values;
}


GType
gst_v4l2element_get_type (void)
{
  static GType v4l2element_type = 0;

  if (!v4l2element_type) {
    static const GTypeInfo v4l2element_info = {
      sizeof (GstV4l2ElementClass),
      (GBaseInitFunc) gst_v4l2element_base_init,
      NULL,
      (GClassInitFunc) gst_v4l2element_class_init,
      NULL,
      NULL,
      sizeof (GstV4l2Element),
      0,
      (GInstanceInitFunc) gst_v4l2element_init,
      NULL
    };
    static const GInterfaceInfo v4l2iface_info = {
      (GInterfaceInitFunc) gst_v4l2_interface_init,
      NULL,
      NULL,
    };
    static const GInterfaceInfo v4l2_tuner_info = {
      (GInterfaceInitFunc) gst_v4l2_tuner_interface_init,
      NULL,
      NULL,
    };
    static const GInterfaceInfo v4l2_xoverlay_info = {
      (GInterfaceInitFunc) gst_v4l2_xoverlay_interface_init,
      NULL,
      NULL,
    };
    static const GInterfaceInfo v4l2_colorbalance_info = {
      (GInterfaceInitFunc) gst_v4l2_color_balance_interface_init,
      NULL,
      NULL,
    };
    static const GInterfaceInfo v4l2_propertyprobe_info = {
      (GInterfaceInitFunc) gst_v4l2_property_probe_interface_init,
      NULL,
      NULL,
    };

    v4l2element_type =
	g_type_register_static (GST_TYPE_ELEMENT,
	"GstV4l2Element", &v4l2element_info, 0);

    g_type_add_interface_static (v4l2element_type,
	GST_TYPE_IMPLEMENTS_INTERFACE, &v4l2iface_info);
    g_type_add_interface_static (v4l2element_type,
	GST_TYPE_TUNER, &v4l2_tuner_info);
    g_type_add_interface_static (v4l2element_type,
	GST_TYPE_X_OVERLAY, &v4l2_xoverlay_info);
    g_type_add_interface_static (v4l2element_type,
	GST_TYPE_COLOR_BALANCE, &v4l2_colorbalance_info);
    g_type_add_interface_static (v4l2element_type,
	GST_TYPE_PROPERTY_PROBE, &v4l2_propertyprobe_info);
  }

  return v4l2element_type;
}


#define GST_TYPE_V4L2_DEVICE_FLAGS (gst_v4l2_device_get_type ())
GType
gst_v4l2_device_get_type (void)
{
  static GType v4l2_device_type = 0;

  if (v4l2_device_type == 0) {
    static const GFlagsValue values[] = {
      {V4L2_CAP_VIDEO_CAPTURE, "CAPTURE",
	  "Device can capture"},
      {V4L2_CAP_VIDEO_OUTPUT, "PLAYBACK",
	  "Device can playback"},
      {V4L2_CAP_VIDEO_OVERLAY, "OVERLAY",
	  "Device can do overlay"},
      {V4L2_CAP_TUNER, "TUNER",
	  "Device has a tuner"},
      {V4L2_CAP_AUDIO, "AUDIO",
	  "Device handles audio"},
      {0, NULL, NULL}
    };

    v4l2_device_type =
	g_flags_register_static ("GstV4l2DeviceTypeFlags", values);
  }

  return v4l2_device_type;
}

static void
gst_v4l2element_base_init (GstV4l2ElementClass * klass)
{
  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);

  klass->devices = NULL;

  gst_element_class_set_details (gstelement_class, &gst_v4l2element_details);
}

static void
gst_v4l2element_class_init (GstV4l2ElementClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);

  parent_class = g_type_class_peek_parent (klass);

  g_object_class_install_property (gobject_class, ARG_DEVICE,
      g_param_spec_string ("device", "Device", "Device location",
	  NULL, G_PARAM_READWRITE));
  g_object_class_install_property (gobject_class, ARG_DEVICE_NAME,
      g_param_spec_string ("device_name", "Device name",
	  "Name of the device", NULL, G_PARAM_READABLE));
  g_object_class_install_property (gobject_class, ARG_FLAGS,
      g_param_spec_flags ("flags", "Flags", "Device type flags",
	  GST_TYPE_V4L2_DEVICE_FLAGS, 0, G_PARAM_READABLE));
  g_object_class_install_property (gobject_class, ARG_NORM,
      g_param_spec_string ("norm", "norm",
	  "Norm to use", NULL, G_PARAM_READWRITE));
  g_object_class_install_property (gobject_class, ARG_CHANNEL,
      g_param_spec_string ("channel", "channel",
	  "input/output to switch to", NULL, G_PARAM_READWRITE));
  g_object_class_install_property (gobject_class, ARG_FREQUENCY,
      g_param_spec_ulong ("frequency", "frequency",
	  "frequency to tune to", 0, G_MAXULONG, 0, G_PARAM_READWRITE));

  /* signals */
  gst_v4l2element_signals[SIGNAL_OPEN] =
      g_signal_new ("open", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
      G_STRUCT_OFFSET (GstV4l2ElementClass, open),
      NULL, NULL, g_cclosure_marshal_VOID__STRING,
      G_TYPE_NONE, 1, G_TYPE_STRING);
  gst_v4l2element_signals[SIGNAL_CLOSE] =
      g_signal_new ("close", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
      G_STRUCT_OFFSET (GstV4l2ElementClass, close),
      NULL, NULL, g_cclosure_marshal_VOID__STRING,
      G_TYPE_NONE, 1, G_TYPE_STRING);

  gobject_class->set_property = gst_v4l2element_set_property;
  gobject_class->get_property = gst_v4l2element_get_property;
  gobject_class->dispose = gst_v4l2element_dispose;

  gstelement_class->change_state = gst_v4l2element_change_state;
}


static void
gst_v4l2element_init (GstV4l2Element * v4l2element)
{
  /* some default values */
  v4l2element->video_fd = -1;
  v4l2element->buffer = NULL;
  v4l2element->device = g_strdup ("/dev/video");
  v4l2element->display = g_strdup (g_getenv ("DISPLAY"));

  v4l2element->channels = NULL;
  v4l2element->norms = NULL;
  v4l2element->colors = NULL;

  v4l2element->overlay = gst_v4l2_xoverlay_new (v4l2element);
}


static void
gst_v4l2element_dispose (GObject * object)
{
  GstV4l2Element *v4l2element = GST_V4L2ELEMENT (object);

  if (v4l2element->overlay) {
    gst_v4l2_xoverlay_free (v4l2element);
  }

  if (v4l2element->display) {
    g_free (v4l2element->display);
  }

  g_free (v4l2element->device);
  v4l2element->device = NULL;
  g_free (v4l2element->norm);
  v4l2element->norm = NULL;
  g_free (v4l2element->channel);
  v4l2element->channel = NULL;

  if (((GObjectClass *) parent_class)->dispose)
    ((GObjectClass *) parent_class)->dispose (object);
}

static void
gst_v4l2element_set_property (GObject * object,
    guint prop_id, const GValue * value, GParamSpec * pspec)
{
  GstV4l2Element *v4l2element;
  GstTuner *tuner;

  /* it's not null if we got it, but it might not be ours */
  g_return_if_fail (GST_IS_V4L2ELEMENT (object));
  v4l2element = GST_V4L2ELEMENT (object);
  /* stupid GstInterface */
  tuner = (GstTuner *) object;

  switch (prop_id) {
    case ARG_DEVICE:
      if (!GST_V4L2_IS_OPEN (v4l2element)) {
	if (v4l2element->device)
	  g_free (v4l2element->device);
	v4l2element->device = g_value_dup_string (value);
      }
      break;
    case ARG_NORM:
      if (GST_V4L2_IS_OPEN (v4l2element)) {
	GstTunerNorm *norm = gst_tuner_get_norm (tuner);

	if (norm) {
	  gst_tuner_set_norm (tuner, norm);
	}
      } else {
	g_free (v4l2element->norm);
	v4l2element->norm = g_value_dup_string (value);
	g_object_notify (object, "norm");
      }
      break;
    case ARG_CHANNEL:
      if (GST_V4L2_IS_OPEN (v4l2element)) {
	GstTunerChannel *channel = gst_tuner_get_channel (tuner);

	if (channel) {
	  gst_tuner_set_channel (tuner, channel);
	}
      } else {
	g_free (v4l2element->channel);
	v4l2element->channel = g_value_dup_string (value);
	g_object_notify (object, "channel");
      }
      break;
    case ARG_FREQUENCY:
      if (GST_V4L2_IS_OPEN (v4l2element)) {
	GstTunerChannel *channel;

	if (!v4l2element->channel)
	  return;
	channel = gst_tuner_get_channel (tuner);
	g_assert (channel);
	gst_tuner_set_frequency (tuner, channel, g_value_get_ulong (value));
      } else {
	v4l2element->frequency = g_value_get_ulong (value);
	g_object_notify (object, "frequency");
      }
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}


static void
gst_v4l2element_get_property (GObject * object,
    guint prop_id, GValue * value, GParamSpec * pspec)
{
  GstV4l2Element *v4l2element;

  /* it's not null if we got it, but it might not be ours */
  g_return_if_fail (GST_IS_V4L2ELEMENT (object));
  v4l2element = GST_V4L2ELEMENT (object);

  switch (prop_id) {
    case ARG_DEVICE:
      g_value_set_string (value, v4l2element->device);
      break;
    case ARG_DEVICE_NAME:{
      gchar *new = NULL;

      if (GST_V4L2_IS_OPEN (v4l2element))
	new = v4l2element->vcap.card;
      g_value_set_string (value, new);
      break;
    }
    case ARG_FLAGS:{
      guint flags = 0;

      if (GST_V4L2_IS_OPEN (v4l2element)) {
	flags |= v4l2element->vcap.capabilities & 30007;
      }
      g_value_set_flags (value, flags);
      break;
    }
    case ARG_NORM:
      g_value_set_string (value, v4l2element->norm);
      break;
    case ARG_CHANNEL:
      g_value_set_string (value, v4l2element->channel);
      break;
    case ARG_FREQUENCY:
      g_value_set_ulong (value, v4l2element->frequency);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}


static GstElementStateReturn
gst_v4l2element_change_state (GstElement * element)
{
  GstV4l2Element *v4l2element;

  g_return_val_if_fail (GST_IS_V4L2ELEMENT (element), GST_STATE_FAILURE);

  v4l2element = GST_V4L2ELEMENT (element);

  /* if going down into NULL state, close the device if it's open
   * if going to READY, open the device (and set some options)
   */
  switch (GST_STATE_TRANSITION (element)) {
    case GST_STATE_NULL_TO_READY:
      gst_v4l2_set_display (v4l2element);

      if (!gst_v4l2_open (v4l2element))
	return GST_STATE_FAILURE;

      gst_v4l2_xoverlay_open (v4l2element);

      /* emit a signal! whoopie! */
      g_signal_emit (G_OBJECT (v4l2element),
	  gst_v4l2element_signals[SIGNAL_OPEN], 0, v4l2element->device);
      break;
    case GST_STATE_READY_TO_NULL:
      gst_v4l2_xoverlay_close (v4l2element);

      if (!gst_v4l2_close (v4l2element))
	return GST_STATE_FAILURE;

      /* emit yet another signal! wheehee! */
      g_signal_emit (G_OBJECT (v4l2element),
	  gst_v4l2element_signals[SIGNAL_CLOSE], 0, v4l2element->device);
      break;
  }

  if (GST_ELEMENT_CLASS (parent_class)->change_state)
    return GST_ELEMENT_CLASS (parent_class)->change_state (element);

  return GST_STATE_SUCCESS;
}