f1c183bc01009173a1091a798162222e8fc2da29
[platform/upstream/glib.git] / gio / gpollableoutputstream.h
1 /* GIO - GLib Input, Output and Streaming Library
2  *
3  * Copyright (C) 2010 Red Hat, Inc.
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General
16  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
17  */
18
19 #ifndef __G_POLLABLE_OUTPUT_STREAM_H__
20 #define __G_POLLABLE_OUTPUT_STREAM_H__
21
22 #if !defined (__GIO_GIO_H_INSIDE__) && !defined (GIO_COMPILATION)
23 #error "Only <gio/gio.h> can be included directly."
24 #endif
25
26 #include <gio/gio.h>
27
28 G_BEGIN_DECLS
29
30 #define G_TYPE_POLLABLE_OUTPUT_STREAM               (g_pollable_output_stream_get_type ())
31 #define G_POLLABLE_OUTPUT_STREAM(obj)               (G_TYPE_CHECK_INSTANCE_CAST ((obj), G_TYPE_POLLABLE_OUTPUT_STREAM, GPollableOutputStream))
32 #define G_IS_POLLABLE_OUTPUT_STREAM(obj)            (G_TYPE_CHECK_INSTANCE_TYPE ((obj), G_TYPE_POLLABLE_OUTPUT_STREAM))
33 #define G_POLLABLE_OUTPUT_STREAM_GET_INTERFACE(obj) (G_TYPE_INSTANCE_GET_INTERFACE ((obj), G_TYPE_POLLABLE_OUTPUT_STREAM, GPollableOutputStreamInterface))
34
35 /**
36  * GPollableOutputStream:
37  *
38  * An interface for a #GOutputStream that can be polled for readability.
39  *
40  * Since: 2.28
41  */
42 typedef struct _GPollableOutputStreamInterface GPollableOutputStreamInterface;
43
44 /**
45  * GPollableOutputStreamInterface:
46  * @g_iface: The parent interface.
47  * @can_poll: Checks if the #GPollableOutputStream instance is actually pollable
48  * @is_writable: Checks if the stream is writable
49  * @create_source: Creates a #GSource to poll the stream
50  * @write_nonblocking: Does a non-blocking write or returns
51  *   %G_IO_ERROR_WOULD_BLOCK
52  *
53  * The interface for pollable output streams.
54  *
55  * The default implementation of @can_poll always returns %TRUE.
56  *
57  * The default implementation of @write_nonblocking calls
58  * g_pollable_output_stream_is_writable(), and then calls
59  * g_output_stream_write() if it returns %TRUE. This means you only
60  * need to override it if it is possible that your @is_writable
61  * implementation may return %TRUE when the stream is not actually
62  * writable.
63  *
64  * Since: 2.28
65  */
66 struct _GPollableOutputStreamInterface
67 {
68   GTypeInterface g_iface;
69
70   /* Virtual Table */
71   gboolean     (*can_poll)          (GPollableOutputStream  *stream);
72
73   gboolean     (*is_writable)       (GPollableOutputStream  *stream);
74   GSource *    (*create_source)     (GPollableOutputStream  *stream,
75                                      GCancellable           *cancellable);
76   gssize       (*write_nonblocking) (GPollableOutputStream  *stream,
77                                      const void             *buffer,
78                                      gsize                   count,
79                                      GError                **error);
80 };
81
82 GLIB_AVAILABLE_IN_ALL
83 GType    g_pollable_output_stream_get_type          (void) G_GNUC_CONST;
84
85 GLIB_AVAILABLE_IN_ALL
86 gboolean g_pollable_output_stream_can_poll          (GPollableOutputStream  *stream);
87
88 GLIB_AVAILABLE_IN_ALL
89 gboolean g_pollable_output_stream_is_writable       (GPollableOutputStream  *stream);
90 GLIB_AVAILABLE_IN_ALL
91 GSource *g_pollable_output_stream_create_source     (GPollableOutputStream  *stream,
92                                                      GCancellable           *cancellable);
93
94 GLIB_AVAILABLE_IN_ALL
95 gssize   g_pollable_output_stream_write_nonblocking (GPollableOutputStream  *stream,
96                                                      const void             *buffer,
97                                                      gsize                   count,
98                                                      GCancellable           *cancellable,
99                                                      GError                **error);
100
101 G_END_DECLS
102
103
104 #endif /* __G_POLLABLE_OUTPUT_STREAM_H__ */
105