gstreamer/plugins/elements/gstfilesink.c

/* GStreamer
 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
 *                    2000 Wim Taymans <wtay@chello.be>
 *                    2006 Wim Taymans <wim@fluendo.com>
 *
 * gstfilesink.c:
 *
 * 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., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */
/**
 * SECTION:element-filesink
 * @see_also: #GstFileSrc
 *
 * Write incoming data to a file in the local file system.
 *
 * <refsect2>
 * <title>Example launch line</title>
 * |[
 * gst-launch-1.0 v4l2src num-buffers=1 ! jpegenc ! filesink location=capture1.jpeg
 * ]| Capture one frame from a v4l2 camera and save as jpeg image.
 * </refsect2>
 */

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

#include "../../gst/gst-i18n-lib.h"

#include <gst/gst.h>
#include <stdio.h>              /* for fseeko() */
#ifdef HAVE_STDIO_EXT_H
#include <stdio_ext.h>          /* for __fbufsize, for debugging */
#endif
#include <errno.h>
#include "gstfilesink.h"
#include <string.h>
#include <sys/types.h>

#ifdef G_OS_WIN32
#include <io.h>                 /* lseek, open, close, read */
#undef lseek
#define lseek _lseeki64
#undef off_t
#define off_t guint64
#undef ftruncate
#define ftruncate _chsize
#undef fsync
#define fsync _commit
#ifdef _MSC_VER                 /* Check if we are using MSVC, fileno is deprecated in favour */
#define fileno _fileno          /* of _fileno */
#endif
#endif

#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef __BIONIC__               /* Android */
#undef lseek
#define lseek lseek64
#undef off_t
#define off_t guint64
#endif

#include "gstelements_private.h"
#include "gstfilesink.h"

static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS_ANY);

#define GST_TYPE_FILE_SINK_BUFFER_MODE (gst_file_sink_buffer_mode_get_type ())
static GType
gst_file_sink_buffer_mode_get_type (void)
{
  static GType buffer_mode_type = 0;
  static const GEnumValue buffer_mode[] = {
    {GST_FILE_SINK_BUFFER_MODE_DEFAULT, "Default buffering", "default"},
    {GST_FILE_SINK_BUFFER_MODE_FULL, "Fully buffered", "full"},
    {GST_FILE_SINK_BUFFER_MODE_LINE, "Line buffered", "line"},
    {GST_FILE_SINK_BUFFER_MODE_UNBUFFERED, "Unbuffered", "unbuffered"},
    {0, NULL, NULL},
  };

  if (!buffer_mode_type) {
    buffer_mode_type =
        g_enum_register_static ("GstFileSinkBufferMode", buffer_mode);
  }
  return buffer_mode_type;
}

GST_DEBUG_CATEGORY_STATIC (gst_file_sink_debug);
#define GST_CAT_DEFAULT gst_file_sink_debug

#define DEFAULT_LOCATION 	NULL
#define DEFAULT_BUFFER_MODE 	GST_FILE_SINK_BUFFER_MODE_DEFAULT
#define DEFAULT_BUFFER_SIZE 	64 * 1024
#define DEFAULT_APPEND		FALSE

enum
{
  PROP_0,
  PROP_LOCATION,
  PROP_BUFFER_MODE,
  PROP_BUFFER_SIZE,
  PROP_APPEND,
  PROP_LAST
};

/* Copy of glib's g_fopen due to win32 libc/cross-DLL brokenness: we can't
 * use the 'file pointer' opened in glib (and returned from this function)
 * in this library, as they may have unrelated C runtimes. */
static FILE *
gst_fopen (const gchar * filename, const gchar * mode)
{
#ifdef G_OS_WIN32
  wchar_t *wfilename = g_utf8_to_utf16 (filename, -1, NULL, NULL, NULL);
  wchar_t *wmode;
  FILE *retval;
  int save_errno;

  if (wfilename == NULL) {
    errno = EINVAL;
    return NULL;
  }

  wmode = g_utf8_to_utf16 (mode, -1, NULL, NULL, NULL);

  if (wmode == NULL) {
    g_free (wfilename);
    errno = EINVAL;
    return NULL;
  }

  retval = _wfopen (wfilename, wmode);
  save_errno = errno;

  g_free (wfilename);
  g_free (wmode);

  errno = save_errno;
  return retval;
#else
  return fopen (filename, mode);
#endif
}

static void gst_file_sink_dispose (GObject * object);

static void gst_file_sink_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_file_sink_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

static gboolean gst_file_sink_open_file (GstFileSink * sink);
static void gst_file_sink_close_file (GstFileSink * sink);

static gboolean gst_file_sink_start (GstBaseSink * sink);
static gboolean gst_file_sink_stop (GstBaseSink * sink);
static gboolean gst_file_sink_event (GstBaseSink * sink, GstEvent * event);
static GstFlowReturn gst_file_sink_render (GstBaseSink * sink,
    GstBuffer * buffer);
static GstFlowReturn gst_file_sink_render_list (GstBaseSink * sink,
    GstBufferList * list);

static gboolean gst_file_sink_do_seek (GstFileSink * filesink,
    guint64 new_offset);
static gboolean gst_file_sink_get_current_offset (GstFileSink * filesink,
    guint64 * p_pos);

static gboolean gst_file_sink_query (GstBaseSink * bsink, GstQuery * query);

static void gst_file_sink_uri_handler_init (gpointer g_iface,
    gpointer iface_data);

#define _do_init \
  G_IMPLEMENT_INTERFACE (GST_TYPE_URI_HANDLER, gst_file_sink_uri_handler_init); \
  GST_DEBUG_CATEGORY_INIT (gst_file_sink_debug, "filesink", 0, "filesink element");
#define gst_file_sink_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstFileSink, gst_file_sink, GST_TYPE_BASE_SINK,
    _do_init);

static void
gst_file_sink_class_init (GstFileSinkClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
  GstBaseSinkClass *gstbasesink_class = GST_BASE_SINK_CLASS (klass);

  gobject_class->dispose = gst_file_sink_dispose;

  gobject_class->set_property = gst_file_sink_set_property;
  gobject_class->get_property = gst_file_sink_get_property;

  g_object_class_install_property (gobject_class, PROP_LOCATION,
      g_param_spec_string ("location", "File Location",
          "Location of the file to write", NULL,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_BUFFER_MODE,
      g_param_spec_enum ("buffer-mode", "Buffering mode",
          "The buffering mode to use", GST_TYPE_FILE_SINK_BUFFER_MODE,
          DEFAULT_BUFFER_MODE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_BUFFER_SIZE,
      g_param_spec_uint ("buffer-size", "Buffering size",
          "Size of buffer in number of bytes for line or full buffer-mode", 0,
          G_MAXUINT, DEFAULT_BUFFER_SIZE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**
   * GstFileSink:append
   *
   * Append to an already existing file.
   */
  g_object_class_install_property (gobject_class, PROP_APPEND,
      g_param_spec_boolean ("append", "Append",
          "Append to an already existing file", DEFAULT_APPEND,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  gst_element_class_set_static_metadata (gstelement_class,
      "File Sink",
      "Sink/File", "Write stream to a file",
      "Thomas Vander Stichele <thomas at apestaart dot org>");
  gst_element_class_add_static_pad_template (gstelement_class, &sinktemplate);

  gstbasesink_class->start = GST_DEBUG_FUNCPTR (gst_file_sink_start);
  gstbasesink_class->stop = GST_DEBUG_FUNCPTR (gst_file_sink_stop);
  gstbasesink_class->query = GST_DEBUG_FUNCPTR (gst_file_sink_query);
  gstbasesink_class->render = GST_DEBUG_FUNCPTR (gst_file_sink_render);
  gstbasesink_class->render_list =
      GST_DEBUG_FUNCPTR (gst_file_sink_render_list);
  gstbasesink_class->event = GST_DEBUG_FUNCPTR (gst_file_sink_event);

  if (sizeof (off_t) < 8) {
    GST_LOG ("No large file support, sizeof (off_t) = %" G_GSIZE_FORMAT "!",
        sizeof (off_t));
  }
}

static void
gst_file_sink_init (GstFileSink * filesink)
{
  filesink->filename = NULL;
  filesink->file = NULL;
  filesink->current_pos = 0;
  filesink->buffer_mode = DEFAULT_BUFFER_MODE;
  filesink->buffer_size = DEFAULT_BUFFER_SIZE;
  filesink->buffer = NULL;
  filesink->append = FALSE;

  gst_base_sink_set_sync (GST_BASE_SINK (filesink), FALSE);
}

static void
gst_file_sink_dispose (GObject * object)
{
  GstFileSink *sink = GST_FILE_SINK (object);

  G_OBJECT_CLASS (parent_class)->dispose (object);

  g_free (sink->uri);
  sink->uri = NULL;
  g_free (sink->filename);
  sink->filename = NULL;
  g_free (sink->buffer);
  sink->buffer = NULL;
  sink->buffer_size = 0;
}

static gboolean
gst_file_sink_set_location (GstFileSink * sink, const gchar * location,
    GError ** error)
{
  if (sink->file)
    goto was_open;

  g_free (sink->filename);
  g_free (sink->uri);
  if (location != NULL) {
    /* we store the filename as we received it from the application. On Windows
     * this should be in UTF8 */
    sink->filename = g_strdup (location);
    sink->uri = gst_filename_to_uri (location, NULL);
    GST_INFO_OBJECT (sink, "filename : %s", sink->filename);
    GST_INFO_OBJECT (sink, "uri      : %s", sink->uri);
  } else {
    sink->filename = NULL;
    sink->uri = NULL;
  }

  return TRUE;

  /* ERRORS */
was_open:
  {
    g_warning ("Changing the `location' property on filesink when a file is "
        "open is not supported.");
    g_set_error (error, GST_URI_ERROR, GST_URI_ERROR_BAD_STATE,
        "Changing the 'location' property on filesink when a file is "
        "open is not supported");
    return FALSE;
  }
}

static void
gst_file_sink_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstFileSink *sink = GST_FILE_SINK (object);

  switch (prop_id) {
    case PROP_LOCATION:
      gst_file_sink_set_location (sink, g_value_get_string (value), NULL);
      break;
    case PROP_BUFFER_MODE:
      sink->buffer_mode = g_value_get_enum (value);
      break;
    case PROP_BUFFER_SIZE:
      sink->buffer_size = g_value_get_uint (value);
      break;
    case PROP_APPEND:
      sink->append = g_value_get_boolean (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_file_sink_get_property (GObject * object, guint prop_id, GValue * value,
    GParamSpec * pspec)
{
  GstFileSink *sink = GST_FILE_SINK (object);

  switch (prop_id) {
    case PROP_LOCATION:
      g_value_set_string (value, sink->filename);
      break;
    case PROP_BUFFER_MODE:
      g_value_set_enum (value, sink->buffer_mode);
      break;
    case PROP_BUFFER_SIZE:
      g_value_set_uint (value, sink->buffer_size);
      break;
    case PROP_APPEND:
      g_value_set_boolean (value, sink->append);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static gboolean
gst_file_sink_open_file (GstFileSink * sink)
{
  gint mode;

  /* open the file */
  if (sink->filename == NULL || sink->filename[0] == '\0')
    goto no_filename;

  if (sink->append)
    sink->file = gst_fopen (sink->filename, "ab");
  else
    sink->file = gst_fopen (sink->filename, "wb");
  if (sink->file == NULL)
    goto open_failed;

  /* see if we are asked to perform a specific kind of buffering */
  if ((mode = sink->buffer_mode) != -1) {
    guint buffer_size;

    /* free previous buffer if any */
    g_free (sink->buffer);

    if (mode == _IONBF) {
      /* no buffering */
      sink->buffer = NULL;
      buffer_size = 0;
    } else {
      /* allocate buffer */
      sink->buffer = g_malloc (sink->buffer_size);
      buffer_size = sink->buffer_size;
    }
    /* Cygwin does not have __fbufsize */
#if defined(HAVE_STDIO_EXT_H) && !defined(__CYGWIN__)
    GST_DEBUG_OBJECT (sink, "change buffer size %u to %u, mode %d",
        (guint) __fbufsize (sink->file), buffer_size, mode);
#else
    GST_DEBUG_OBJECT (sink, "change  buffer size to %u, mode %d",
        sink->buffer_size, mode);
#endif
    if (setvbuf (sink->file, sink->buffer, mode, buffer_size) != 0) {
      GST_WARNING_OBJECT (sink, "warning: setvbuf failed: %s",
          g_strerror (errno));
    }
  }

  sink->current_pos = 0;
  /* try to seek in the file to figure out if it is seekable */
  sink->seekable = gst_file_sink_do_seek (sink, 0);

  GST_DEBUG_OBJECT (sink, "opened file %s, seekable %d",
      sink->filename, sink->seekable);

  return TRUE;

  /* ERRORS */
no_filename:
  {
    GST_ELEMENT_ERROR (sink, RESOURCE, NOT_FOUND,
        (_("No file name specified for writing.")), (NULL));
    return FALSE;
  }
open_failed:
  {
    GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE,
        (_("Could not open file \"%s\" for writing."), sink->filename),
        GST_ERROR_SYSTEM);
    return FALSE;
  }
}

static void
gst_file_sink_close_file (GstFileSink * sink)
{
  if (sink->file) {
    if (fclose (sink->file) != 0)
      GST_ELEMENT_ERROR (sink, RESOURCE, CLOSE,
          (_("Error closing file \"%s\"."), sink->filename), GST_ERROR_SYSTEM);

    GST_DEBUG_OBJECT (sink, "closed file");
    sink->file = NULL;

    g_free (sink->buffer);
    sink->buffer = NULL;
  }
}

static gboolean
gst_file_sink_query (GstBaseSink * bsink, GstQuery * query)
{
  gboolean res;
  GstFileSink *self;
  GstFormat format;

  self = GST_FILE_SINK (bsink);

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_POSITION:
      gst_query_parse_position (query, &format, NULL);

      switch (format) {
        case GST_FORMAT_DEFAULT:
        case GST_FORMAT_BYTES:
          gst_query_set_position (query, GST_FORMAT_BYTES, self->current_pos);
          res = TRUE;
          break;
        default:
          res = FALSE;
          break;
      }
      break;

    case GST_QUERY_FORMATS:
      gst_query_set_formats (query, 2, GST_FORMAT_DEFAULT, GST_FORMAT_BYTES);
      res = TRUE;
      break;

    case GST_QUERY_URI:
      gst_query_set_uri (query, self->uri);
      res = TRUE;
      break;

    case GST_QUERY_SEEKING:
      gst_query_parse_seeking (query, &format, NULL, NULL, NULL);
      if (format == GST_FORMAT_BYTES || format == GST_FORMAT_DEFAULT) {
        gst_query_set_seeking (query, GST_FORMAT_BYTES, self->seekable, 0, -1);
      } else {
        gst_query_set_seeking (query, format, FALSE, 0, -1);
      }
      res = TRUE;
      break;

    default:
      res = GST_BASE_SINK_CLASS (parent_class)->query (bsink, query);
      break;
  }
  return res;
}

#ifdef HAVE_FSEEKO
# define __GST_STDIO_SEEK_FUNCTION "fseeko"
#elif defined (G_OS_UNIX) || defined (G_OS_WIN32)
# define __GST_STDIO_SEEK_FUNCTION "lseek"
#else
# define __GST_STDIO_SEEK_FUNCTION "fseek"
#endif

static gboolean
gst_file_sink_do_seek (GstFileSink * filesink, guint64 new_offset)
{
  GST_DEBUG_OBJECT (filesink, "Seeking to offset %" G_GUINT64_FORMAT
      " using " __GST_STDIO_SEEK_FUNCTION, new_offset);

  if (fflush (filesink->file))
    goto flush_failed;

#ifdef HAVE_FSEEKO
  if (fseeko (filesink->file, (off_t) new_offset, SEEK_SET) != 0)
    goto seek_failed;
#elif defined (G_OS_UNIX) || defined (G_OS_WIN32)
  if (lseek (fileno (filesink->file), (off_t) new_offset,
          SEEK_SET) == (off_t) - 1)
    goto seek_failed;
#else
  if (fseek (filesink->file, (long) new_offset, SEEK_SET) != 0)
    goto seek_failed;
#endif

  /* adjust position reporting after seek;
   * presumably this should basically yield new_offset */
  gst_file_sink_get_current_offset (filesink, &filesink->current_pos);

  return TRUE;

  /* ERRORS */
flush_failed:
  {
    GST_DEBUG_OBJECT (filesink, "Flush failed: %s", g_strerror (errno));
    return FALSE;
  }
seek_failed:
  {
    GST_DEBUG_OBJECT (filesink, "Seeking failed: %s", g_strerror (errno));
    return FALSE;
  }
}

/* handle events (search) */
static gboolean
gst_file_sink_event (GstBaseSink * sink, GstEvent * event)
{
  GstEventType type;
  GstFileSink *filesink;

  filesink = GST_FILE_SINK (sink);

  type = GST_EVENT_TYPE (event);

  switch (type) {
    case GST_EVENT_SEGMENT:
    {
      const GstSegment *segment;

      gst_event_parse_segment (event, &segment);

      if (segment->format == GST_FORMAT_BYTES) {
        /* only try to seek and fail when we are going to a different
         * position */
        if (filesink->current_pos != segment->start) {
          /* FIXME, the seek should be performed on the pos field, start/stop are
           * just boundaries for valid bytes offsets. We should also fill the file
           * with zeroes if the new position extends the current EOF (sparse streams
           * and segment accumulation). */
          if (!gst_file_sink_do_seek (filesink, (guint64) segment->start))
            goto seek_failed;
        } else {
          GST_DEBUG_OBJECT (filesink, "Ignored SEGMENT, no seek needed");
        }
      } else {
        GST_DEBUG_OBJECT (filesink,
            "Ignored SEGMENT event of format %u (%s)", (guint) segment->format,
            gst_format_get_name (segment->format));
      }
      break;
    }
    case GST_EVENT_FLUSH_STOP:
      if (filesink->current_pos != 0 && filesink->seekable) {
        gst_file_sink_do_seek (filesink, 0);
        if (ftruncate (fileno (filesink->file), 0))
          goto flush_failed;
      }
      break;
    case GST_EVENT_EOS:
      if (fflush (filesink->file))
        goto flush_failed;
      break;
    default:
      break;
  }

  return GST_BASE_SINK_CLASS (parent_class)->event (sink, event);

  /* ERRORS */
seek_failed:
  {
    GST_ELEMENT_ERROR (filesink, RESOURCE, SEEK,
        (_("Error while seeking in file \"%s\"."), filesink->filename),
        GST_ERROR_SYSTEM);
    gst_event_unref (event);
    return FALSE;
  }
flush_failed:
  {
    GST_ELEMENT_ERROR (filesink, RESOURCE, WRITE,
        (_("Error while writing to file \"%s\"."), filesink->filename),
        GST_ERROR_SYSTEM);
    gst_event_unref (event);
    return FALSE;
  }
}

static gboolean
gst_file_sink_get_current_offset (GstFileSink * filesink, guint64 * p_pos)
{
  off_t ret = -1;

#ifdef HAVE_FTELLO
  ret = ftello (filesink->file);
#elif defined (G_OS_UNIX) || defined (G_OS_WIN32)
  if (fflush (filesink->file)) {
    GST_DEBUG_OBJECT (filesink, "Flush failed: %s", g_strerror (errno));
    /* ignore and continue */
  }
  ret = lseek (fileno (filesink->file), 0, SEEK_CUR);
#else
  ret = (off_t) ftell (filesink->file);
#endif

  if (ret != (off_t) - 1)
    *p_pos = (guint64) ret;

  return (ret != (off_t) - 1);
}

static GstFlowReturn
gst_file_sink_render_buffers (GstFileSink * sink, GstBuffer ** buffers,
    guint num_buffers, guint8 * mem_nums, guint total_mems)
{
  GST_DEBUG_OBJECT (sink,
      "writing %u buffers (%u memories) at position %" G_GUINT64_FORMAT,
      num_buffers, total_mems, sink->current_pos);

  return gst_writev_buffers (GST_OBJECT_CAST (sink), fileno (sink->file), NULL,
      buffers, num_buffers, mem_nums, total_mems, NULL, &sink->current_pos);
}

static GstFlowReturn
gst_file_sink_render_list (GstBaseSink * bsink, GstBufferList * buffer_list)
{
  GstFlowReturn flow;
  GstBuffer **buffers;
  GstFileSink *sink;
  guint8 *mem_nums;
  guint total_mems;
  guint i, num_buffers;
  gboolean sync_after = FALSE;

  sink = GST_FILE_SINK_CAST (bsink);

  num_buffers = gst_buffer_list_length (buffer_list);
  if (num_buffers == 0)
    goto no_data;

  /* extract buffers from list and count memories */
  buffers = g_newa (GstBuffer *, num_buffers);
  mem_nums = g_newa (guint8, num_buffers);
  for (i = 0, total_mems = 0; i < num_buffers; ++i) {
    buffers[i] = gst_buffer_list_get (buffer_list, i);
    mem_nums[i] = gst_buffer_n_memory (buffers[i]);
    total_mems += mem_nums[i];
    if (GST_BUFFER_FLAG_IS_SET (buffers[i], GST_BUFFER_FLAG_SYNC_AFTER))
      sync_after = TRUE;
  }

  flow =
      gst_file_sink_render_buffers (sink, buffers, num_buffers, mem_nums,
      total_mems);

  if (flow == GST_FLOW_OK && sync_after) {
    if (fflush (sink->file) || fsync (fileno (sink->file))) {
      GST_ELEMENT_ERROR (sink, RESOURCE, WRITE,
          (_("Error while writing to file \"%s\"."), sink->filename),
          ("%s", g_strerror (errno)));
      flow = GST_FLOW_ERROR;
    }
  }

  return flow;

no_data:
  {
    GST_LOG_OBJECT (sink, "empty buffer list");
    return GST_FLOW_OK;
  }
}

static GstFlowReturn
gst_file_sink_render (GstBaseSink * sink, GstBuffer * buffer)
{
  GstFileSink *filesink;
  GstFlowReturn flow;
  guint8 n_mem;

  filesink = GST_FILE_SINK_CAST (sink);

  n_mem = gst_buffer_n_memory (buffer);

  if (n_mem > 0)
    flow = gst_file_sink_render_buffers (filesink, &buffer, 1, &n_mem, n_mem);
  else
    flow = GST_FLOW_OK;

  if (flow == GST_FLOW_OK &&
      GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_SYNC_AFTER)) {
    if (fflush (filesink->file) || fsync (fileno (filesink->file))) {
      GST_ELEMENT_ERROR (filesink, RESOURCE, WRITE,
          (_("Error while writing to file \"%s\"."), filesink->filename),
          ("%s", g_strerror (errno)));
      flow = GST_FLOW_ERROR;
    }
  }

  return flow;
}

static gboolean
gst_file_sink_start (GstBaseSink * basesink)
{
  return gst_file_sink_open_file (GST_FILE_SINK (basesink));
}

static gboolean
gst_file_sink_stop (GstBaseSink * basesink)
{
  gst_file_sink_close_file (GST_FILE_SINK (basesink));
  return TRUE;
}

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

static GstURIType
gst_file_sink_uri_get_type (GType type)
{
  return GST_URI_SINK;
}

static const gchar *const *
gst_file_sink_uri_get_protocols (GType type)
{
  static const gchar *protocols[] = { "file", NULL };

  return protocols;
}

static gchar *
gst_file_sink_uri_get_uri (GstURIHandler * handler)
{
  GstFileSink *sink = GST_FILE_SINK (handler);

  /* FIXME: make thread-safe */
  return g_strdup (sink->uri);
}

static gboolean
gst_file_sink_uri_set_uri (GstURIHandler * handler, const gchar * uri,
    GError ** error)
{
  gchar *location;
  gboolean ret;
  GstFileSink *sink = GST_FILE_SINK (handler);

  /* allow file://localhost/foo/bar by stripping localhost but fail
   * for every other hostname */
  if (g_str_has_prefix (uri, "file://localhost/")) {
    char *tmp;

    /* 16 == strlen ("file://localhost") */
    tmp = g_strconcat ("file://", uri + 16, NULL);
    /* we use gst_uri_get_location() although we already have the
     * "location" with uri + 16 because it provides unescaping */
    location = gst_uri_get_location (tmp);
    g_free (tmp);
  } else if (strcmp (uri, "file://") == 0) {
    /* Special case for "file://" as this is used by some applications
     *  to test with gst_element_make_from_uri if there's an element
     *  that supports the URI protocol. */
    gst_file_sink_set_location (sink, NULL, NULL);
    return TRUE;
  } else {
    location = gst_uri_get_location (uri);
  }

  if (!location) {
    g_set_error_literal (error, GST_URI_ERROR, GST_URI_ERROR_BAD_URI,
        "File URI without location");
    return FALSE;
  }

  if (!g_path_is_absolute (location)) {
    g_set_error_literal (error, GST_URI_ERROR, GST_URI_ERROR_BAD_URI,
        "File URI location must be an absolute path");
    g_free (location);
    return FALSE;
  }

  ret = gst_file_sink_set_location (sink, location, error);
  g_free (location);

  return ret;
}

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

  iface->get_type = gst_file_sink_uri_get_type;
  iface->get_protocols = gst_file_sink_uri_get_protocols;
  iface->get_uri = gst_file_sink_uri_get_uri;
  iface->set_uri = gst_file_sink_uri_set_uri;
}