1/* GIO - GLib Input, Output and Streaming Library
2 *
3 * Copyright (C) 2006-2007 Red Hat, Inc.
4 *
5 * SPDX-License-Identifier: LGPL-2.1-or-later
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General
18 * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 *
20 * Author: Alexander Larsson <alexl@redhat.com>
21 */
22
23#ifndef __G_SEEKABLE_H__
24#define __G_SEEKABLE_H__
25
26#if !defined (__GIO_GIO_H_INSIDE__) && !defined (GIO_COMPILATION)
27#error "Only <gio/gio.h> can be included directly."
28#endif
29
30#include <gio/giotypes.h>
31
32G_BEGIN_DECLS
33
34#define G_TYPE_SEEKABLE (g_seekable_get_type ())
35#define G_SEEKABLE(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), G_TYPE_SEEKABLE, GSeekable))
36#define G_IS_SEEKABLE(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), G_TYPE_SEEKABLE))
37#define G_SEEKABLE_GET_IFACE(obj) (G_TYPE_INSTANCE_GET_INTERFACE ((obj), G_TYPE_SEEKABLE, GSeekableIface))
38
39typedef struct _GSeekableIface GSeekableIface;
40
41/**
42 * GSeekableIface:
43 * @g_iface: The parent interface.
44 * @tell: Tells the current location within a stream.
45 * @can_seek: Checks if seeking is supported by the stream.
46 * @seek: Seeks to a location within a stream.
47 * @can_truncate: Checks if truncation is supported by the stream.
48 * @truncate_fn: Truncates a stream.
49 *
50 * Provides an interface for implementing seekable functionality on I/O Streams.
51 **/
52struct _GSeekableIface
53{
54 GTypeInterface g_iface;
55
56 /* Virtual Table */
57
58 goffset (* tell) (GSeekable *seekable);
59
60 gboolean (* can_seek) (GSeekable *seekable);
61 gboolean (* seek) (GSeekable *seekable,
62 goffset offset,
63 GSeekType type,
64 GCancellable *cancellable,
65 GError **error);
66
67 gboolean (* can_truncate) (GSeekable *seekable);
68 gboolean (* truncate_fn) (GSeekable *seekable,
69 goffset offset,
70 GCancellable *cancellable,
71 GError **error);
72
73 /* TODO: Async seek/truncate */
74};
75
76GIO_AVAILABLE_IN_ALL
77GType g_seekable_get_type (void) G_GNUC_CONST;
78
79GIO_AVAILABLE_IN_ALL
80goffset g_seekable_tell (GSeekable *seekable);
81GIO_AVAILABLE_IN_ALL
82gboolean g_seekable_can_seek (GSeekable *seekable);
83GIO_AVAILABLE_IN_ALL
84gboolean g_seekable_seek (GSeekable *seekable,
85 goffset offset,
86 GSeekType type,
87 GCancellable *cancellable,
88 GError **error);
89GIO_AVAILABLE_IN_ALL
90gboolean g_seekable_can_truncate (GSeekable *seekable);
91GIO_AVAILABLE_IN_ALL
92gboolean g_seekable_truncate (GSeekable *seekable,
93 goffset offset,
94 GCancellable *cancellable,
95 GError **error);
96
97G_END_DECLS
98
99
100#endif /* __G_SEEKABLE_H__ */
101

source code of include/glib-2.0/gio/gseekable.h