/* dzl-ring.h
*
* Copyright (C) 2010 Christian Hergert <chris@dronelabs.com>
*
* This file 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 file 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 General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __DZL_RING_H__
#define __DZL_RING_H__
#include <glib-object.h>
#include "dzl-version-macros.h"
G_BEGIN_DECLS
/**
* dzl_ring_append_val:
* @ring: A #DzlRing.
* @val: A value to append to the #DzlRing.
*
* Appends a value to the ring buffer. @val must be a variable as it is
* referenced to.
*
* Returns: None.
*/
#define dzl_ring_append_val(ring, val) dzl_ring_append_vals(ring, &(val), 1)
/**
* _dzl_ring_index: (skip)
*
* Used to convert an index to valid indx within the ring. We only support
* offsets within +/- one range of the length of the ring.
*/
#define _dzl_ring_index(ring, i) \
({ \
gint __idx = (gint)(ring->pos) + i; \
if (__idx < 0) \
__idx += (gint)ring->len; \
else if (__idx >= (gint)(ring)->len) \
__idx -= (gint)ring->len; \
__idx; \
})
/**
* dzl_ring_get_index:
* @ring: A #DzlRing.
* @type: The type to extract.
* @i: The index within the #DzlRing relative to the current position.
*
* Retrieves the value at the given index from the #DzlRing. The value
* is cast to @type. You may retrieve a pointer to the value within the
* array by using &.
*
* [[
* gdouble *v = &dzl_ring_get_index(ring, gdouble, 0);
* gdouble v = dzl_ring_get_index(ring, gdouble, 0);
* ]]
*
* Returns: The value at the given index.
*/
#define dzl_ring_get_index(ring, type, i) \
((((type *)(gpointer)(ring)->data))[_dzl_ring_index(ring, i)])
typedef struct
{
guint8 *data;
guint len;
guint pos;
/*< private >*/
} DzlRing;
DZL_AVAILABLE_IN_ALL
GType dzl_ring_get_type (void);
DZL_AVAILABLE_IN_ALL
DzlRing *dzl_ring_sized_new (guint element_size,
guint reserved_size,
GDestroyNotify element_destroy);
DZL_AVAILABLE_IN_ALL
guint dzl_ring_append_vals (DzlRing *ring,
gconstpointer data,
guint len);
DZL_AVAILABLE_IN_ALL
void dzl_ring_foreach (DzlRing *ring,
GFunc func,
gpointer user_data);
DZL_AVAILABLE_IN_ALL
DzlRing *dzl_ring_ref (DzlRing *ring);
DZL_AVAILABLE_IN_ALL
void dzl_ring_unref (DzlRing *ring);
G_DEFINE_AUTOPTR_CLEANUP_FUNC (DzlRing, dzl_ring_unref)
G_END_DECLS
#endif /* __DZL_RING_H__ */