gstreamer/gst/debug/gstpushfilesrc.c

/* GStreamer Push File Source
 * Copyright (C) <2007> Tim-Philipp Müller <tim centricular 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.
 */

/**
 * SECTION:element-pushfilesrc
 * @short_description: Works like a filesrc, but only push-based (for debugging)
 * @see_also: filesrc
 *
 * <refsect2>
 * <para>
 * This element is only useful for debugging purposes. It implements an URI
 * protocol handler for the 'pushfile' protocol and behaves like a file source
 * element that cannot be activated in pull-mode. This makes it very easy to
 * debug demuxers or decoders that can operate both pull and push-based in
 * connection with the playbin element (which creates a source based on the
 * URI passed).
 * </para>
 * <title>Example launch line</title>
 * <para>
 * <programlisting>
 * gst-launch -m playbin uri=pushfile:///home/you/some/file.ogg
 * </programlisting>
 * This plays back the given file using playbin, with the demuxer operating
 * push-based.
 * </para>
 * </refsect2>
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "gstpushfilesrc.h"

#include <gst/gst.h>

GST_DEBUG_CATEGORY_STATIC (pushfilesrc_debug);
#define GST_CAT_DEFAULT pushfilesrc_debug

static const GstElementDetails pushfilesrc_details =
GST_ELEMENT_DETAILS ("Push File Source",
    "Testing",
    "Implements pushfile:// URI-handler for push-based file access",
    "Tim-Philipp Müller <tim centricular net>");

static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS_ANY);

static void gst_push_file_src_uri_handler_init (gpointer g_iface,
    gpointer iface_data);
static void gst_file_push_src_add_uri_handler (GType type);

GST_BOILERPLATE_FULL (GstPushFileSrc, gst_push_file_src, GstBin, GST_TYPE_BIN,
    gst_file_push_src_add_uri_handler);

static void
gst_file_push_src_add_uri_handler (GType type)
{
  static const GInterfaceInfo info = {
    gst_push_file_src_uri_handler_init,
    NULL,
    NULL
  };

  g_type_add_interface_static (type, GST_TYPE_URI_HANDLER, &info);
  GST_DEBUG_CATEGORY_INIT (pushfilesrc_debug, "pushfilesrc", 0,
      "pushfilesrc element");
}

static void
gst_push_file_src_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&srctemplate));

  gst_element_class_set_details (element_class, &pushfilesrc_details);
}

static void
gst_push_file_src_dispose (GObject * obj)
{
  GstPushFileSrc *src = GST_PUSH_FILE_SRC (obj);

  if (src->srcpad) {
    gst_element_remove_pad (GST_ELEMENT (src), src->srcpad);
    src->srcpad = NULL;
  }
  if (src->filesrc) {
    gst_bin_remove (GST_BIN (src), src->filesrc);
    src->filesrc = NULL;
  }

  G_OBJECT_CLASS (parent_class)->dispose (obj);
}

static void
gst_push_file_src_class_init (GstPushFileSrcClass * g_class)
{
  GObjectClass *gobject_class;

  gobject_class = G_OBJECT_CLASS (g_class);

  gobject_class->dispose = gst_push_file_src_dispose;
}

static gboolean
gst_push_file_src_ghostpad_checkgetrange (GstPad * pad)
{
  return FALSE;
}

static void
gst_push_file_src_init (GstPushFileSrc * src, GstPushFileSrcClass * g_class)
{
  src->filesrc = gst_element_factory_make ("filesrc", "real-filesrc");
  if (src->filesrc) {
    GstPad *pad;

    gst_bin_add (GST_BIN (src), src->filesrc);
    pad = gst_element_get_static_pad (src->filesrc, "src");
    g_assert (pad != NULL);
    src->srcpad = gst_ghost_pad_new ("src", pad);
    /* FIXME^H^HCORE: try pushfile:///foo/bar.ext ! typefind ! fakesink without
     * this and watch core bugginess (some pad stays in flushing state) */
    gst_pad_set_checkgetrange_function (src->srcpad,
        GST_DEBUG_FUNCPTR (gst_push_file_src_ghostpad_checkgetrange));
    gst_element_add_pad (GST_ELEMENT (src), src->srcpad);
    gst_object_unref (pad);
  }
}

/*** GSTURIHANDLER INTERFACE *************************************************/

static GstURIType
gst_push_file_src_uri_get_type (void)
{
  return GST_URI_SRC;
}
static gchar **
gst_push_file_src_uri_get_protocols (void)
{
  static gchar *protocols[] = { "pushfile", NULL };

  return protocols;
}
static const gchar *
gst_push_file_src_uri_get_uri (GstURIHandler * handler)
{
  GstPushFileSrc *src = GST_PUSH_FILE_SRC (handler);

  if (src->filesrc == NULL)
    return NULL;

  return gst_uri_handler_get_uri (GST_URI_HANDLER (src->filesrc));
}

static gboolean
gst_push_file_src_uri_set_uri (GstURIHandler * handler, const gchar * uri)
{
  GstPushFileSrc *src = GST_PUSH_FILE_SRC (handler);

  if (src->filesrc == NULL || !g_str_has_prefix (uri, "pushfile://"))
    return FALSE;

  /* skip 'push' bit */
  return gst_uri_handler_set_uri (GST_URI_HANDLER (src->filesrc), uri + 4);
}

static void
gst_push_file_src_uri_handler_init (gpointer g_iface, gpointer iface_data)
{
  GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;

  iface->get_type = gst_push_file_src_uri_get_type;
  iface->get_protocols = gst_push_file_src_uri_get_protocols;
  iface->get_uri = gst_push_file_src_uri_get_uri;
  iface->set_uri = gst_push_file_src_uri_set_uri;
}

gboolean
gst_push_file_src_plugin_init (GstPlugin * plugin)
{
  return gst_element_register (plugin, "pushfilesrc", GST_RANK_NONE,
      GST_TYPE_PUSH_FILE_SRC);
}