/* GIO - GLib Input, Output and Streaming Library

 * 

 * Copyright (C) 2006-2007 Red Hat, Inc.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General

 * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.

 *

 * Author: Christian Kellner <gicmo@gnome.org> 

 */

#include "config.h"

#include "gfilterinputstream.h"

#include "ginputstream.h"

#include "glibintl.h"

/**

 * SECTION:gfilterinputstream

 * @short_description: Filter Input Stream

 * @include: gio/gio.h

 *

 * Base class for input stream implementations that perform some

 * kind of filtering operation on a base stream. Typical examples

 * of filtering operations are character set conversion, compression

 * and byte order flipping.

 **/

enum {

  PROP_0,

  PROP_BASE_STREAM,

  PROP_CLOSE_BASE

};

static void     g_filter_input_stream_set_property (GObject      *object,

                                                    guint         prop_id,

                                                    const GValue *value,

                                                    GParamSpec   *pspec);

static void     g_filter_input_stream_get_property (GObject      *object,

                                                    guint         prop_id,

                                                    GValue       *value,

                                                    GParamSpec   *pspec);

static void     g_filter_input_stream_finalize     (GObject *object);

static gssize   g_filter_input_stream_read         (GInputStream         *stream,

                                                    void                 *buffer,

                                                    gsize                 count,

                                                    GCancellable         *cancellable,

                                                    GError              **error);

static gssize   g_filter_input_stream_skip         (GInputStream         *stream,

                                                    gsize                 count,

                                                    GCancellable         *cancellable,

                                                    GError              **error);

static gboolean g_filter_input_stream_close        (GInputStream         *stream,

                                                    GCancellable         *cancellable,

                                                    GError              **error);

typedef struct

{

  gboolean close_base;

} GFilterInputStreamPrivate;

G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GFilterInputStream, g_filter_input_stream, G_TYPE_INPUT_STREAM)

static void

g_filter_input_stream_class_init (GFilterInputStreamClass *klass)

{

  GObjectClass *object_class;

  GInputStreamClass *istream_class;

  object_class = G_OBJECT_CLASS (klass);

  object_class->get_property = g_filter_input_stream_get_property;

  object_class->set_property = g_filter_input_stream_set_property;

  object_class->finalize     = g_filter_input_stream_finalize;

  istream_class = G_INPUT_STREAM_CLASS (klass);

  istream_class->read_fn  = g_filter_input_stream_read;

  istream_class->skip  = g_filter_input_stream_skip;

  istream_class->close_fn = g_filter_input_stream_close;

  g_object_class_install_property (object_class,

                                   PROP_BASE_STREAM,

                                   g_param_spec_object ("base-stream",

                                                         P_("The Filter Base Stream"),

                                                         P_("The underlying base stream on which the io ops will be done."),

                                                         G_TYPE_INPUT_STREAM,

                                                         G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | 

                                                         G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));

  g_object_class_install_property (object_class,

                                   PROP_CLOSE_BASE,

                                   g_param_spec_boolean ("close-base-stream",

                                                         P_("Close Base Stream"),

                                                         P_("If the base stream should be closed when the filter stream is closed."),

                                                         TRUE, G_PARAM_READWRITE | G_PARAM_CONSTRUCT |

                                                         G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));

}

static void

g_filter_input_stream_set_property (GObject         *object,

                                    guint            prop_id,

                                    const GValue    *value,

                                    GParamSpec      *pspec)

{

  GFilterInputStream *filter_stream;

  GObject *obj;

  filter_stream = G_FILTER_INPUT_STREAM (object);

  switch (prop_id) 

    {

    case PROP_BASE_STREAM:

      obj = g_value_dup_object (value);

      filter_stream->base_stream = G_INPUT_STREAM (obj); 

      break;

    case PROP_CLOSE_BASE:

      g_filter_input_stream_set_close_base_stream (filter_stream,

                                                   g_value_get_boolean (value));

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

    }

}

static void

g_filter_input_stream_get_property (GObject    *object,

                                    guint       prop_id,

                                    GValue     *value,

                                    GParamSpec *pspec)

{

  GFilterInputStream *filter_stream;

  GFilterInputStreamPrivate *priv;

  filter_stream = G_FILTER_INPUT_STREAM (object);

  priv = g_filter_input_stream_get_instance_private (filter_stream);

  switch (prop_id)

    {

    case PROP_BASE_STREAM:

      g_value_set_object (value, filter_stream->base_stream);

      break;

    case PROP_CLOSE_BASE:

      g_value_set_boolean (value, priv->close_base);

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

    }

}

static void

g_filter_input_stream_finalize (GObject *object)

{

  GFilterInputStream *stream;

  stream = G_FILTER_INPUT_STREAM (object);

  g_object_unref (stream->base_stream);

  G_OBJECT_CLASS (g_filter_input_stream_parent_class)->finalize (object);

}

static void

g_filter_input_stream_init (GFilterInputStream *stream)

{

}

/**

 * g_filter_input_stream_get_base_stream:

 * @stream: a #GFilterInputStream.

 * 

 * Gets the base stream for the filter stream.

 *

 * Returns: (transfer none): a #GInputStream.

 **/

GInputStream *

g_filter_input_stream_get_base_stream (GFilterInputStream *stream)

{

  g_return_val_if_fail (G_IS_FILTER_INPUT_STREAM (stream), NULL);

  return stream->base_stream;

}

/**

 * g_filter_input_stream_get_close_base_stream:

 * @stream: a #GFilterInputStream.

 *

 * Returns whether the base stream will be closed when @stream is

 * closed.

 *

 * Returns: %TRUE if the base stream will be closed.

 **/

gboolean

g_filter_input_stream_get_close_base_stream (GFilterInputStream *stream)

{

  GFilterInputStreamPrivate *priv;

  g_return_val_if_fail (G_IS_FILTER_INPUT_STREAM (stream), FALSE);

  priv = g_filter_input_stream_get_instance_private (stream);

  return priv->close_base;

}

/**

 * g_filter_input_stream_set_close_base_stream:

 * @stream: a #GFilterInputStream.

 * @close_base: %TRUE to close the base stream.

 *

 * Sets whether the base stream will be closed when @stream is closed.

 **/

void

g_filter_input_stream_set_close_base_stream (GFilterInputStream *stream,

                                             gboolean            close_base)

{

  GFilterInputStreamPrivate *priv;

  g_return_if_fail (G_IS_FILTER_INPUT_STREAM (stream));

  close_base = !!close_base;

  priv = g_filter_input_stream_get_instance_private (stream);

  if (priv->close_base != close_base)

    {

      priv->close_base = close_base;

      g_object_notify (G_OBJECT (stream), "close-base-stream");

    }

}

static gssize

g_filter_input_stream_read (GInputStream  *stream,

                            void          *buffer,

                            gsize          count,

                            GCancellable  *cancellable,

                            GError       **error)

{

  GFilterInputStream *filter_stream;

  GInputStream       *base_stream;

  gssize              nread;

  filter_stream = G_FILTER_INPUT_STREAM (stream);

  base_stream = filter_stream->base_stream;

  nread = g_input_stream_read (base_stream,

                               buffer,

                               count,

                               cancellable,

                               error);

  return nread;

}

static gssize

g_filter_input_stream_skip (GInputStream  *stream,

                            gsize          count,

                            GCancellable  *cancellable,

                            GError       **error)

{

  GFilterInputStream *filter_stream;

  GInputStream       *base_stream;

  gssize              nskipped;

  filter_stream = G_FILTER_INPUT_STREAM (stream);

  base_stream = filter_stream->base_stream;

  nskipped = g_input_stream_skip (base_stream,

                                  count,

                                  cancellable,

                                  error);

  return nskipped;

}

static gboolean

g_filter_input_stream_close (GInputStream  *stream,

                             GCancellable  *cancellable,

                             GError       **error)

{

  GFilterInputStream *filter_stream = G_FILTER_INPUT_STREAM (stream);

  GFilterInputStreamPrivate *priv = g_filter_input_stream_get_instance_private (filter_stream);

  gboolean res = TRUE;

  if (priv->close_base)

    {

      res = g_input_stream_close (filter_stream->base_stream,

                                  cancellable,

                                  error);

    }

  return res;

}