glib.Once source code

1 /*
2  * This file is part of gtkD.
3  *
4  * gtkD is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU Lesser General Public License
6  * as published by the Free Software Foundation; either version 3
7  * of the License, or (at your option) any later version, with
8  * some exceptions, please read the COPYING file.
9  *
10  * gtkD 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
13  * GNU Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public License
16  * along with gtkD; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
18  */
19 
20 // generated automatically - do not change
21 // find conversion definition on APILookup.txt
22 // implement new conversion functionalities on the wrap.utils pakage
23 
24 
25 module glib.Once;
26 
27 private import gtkc.glib;
28 public  import gtkc.glibtypes;
29 
30 
31 /**
32  * A #GOnce struct controls a one-time initialization function. Any
33  * one-time initialization function must have its own unique #GOnce
34  * struct.
35  *
36  * Since: 2.4
37  */
38 public class Once
39 {
40 	/** the main Gtk struct */
41 	protected GOnce* gOnce;
42 	protected bool ownedRef;
43 
44 	/** Get the main Gtk struct */
45 	public GOnce* getOnceStruct(bool transferOwnership = false)
46 	{
47 		if (transferOwnership)
48 			ownedRef = false;
49 		return gOnce;
50 	}
51 
52 	/** the main Gtk struct as a void* */
53 	protected void* getStruct()
54 	{
55 		return cast(void*)gOnce;
56 	}
57 
58 	/**
59 	 * Sets our main struct and passes it to the parent class.
60 	 */
61 	public this (GOnce* gOnce, bool ownedRef = false)
62 	{
63 		this.gOnce = gOnce;
64 		this.ownedRef = ownedRef;
65 	}
66 
67 
68 	/** */
69 	public void* impl(GThreadFunc func, void* arg)
70 	{
71 		return g_once_impl(gOnce, func, arg);
72 	}
73 
74 	/**
75 	 * Function to be called when starting a critical initialization
76 	 * section. The argument @location must point to a static
77 	 * 0-initialized variable that will be set to a value other than 0 at
78 	 * the end of the initialization section. In combination with
79 	 * g_once_init_leave() and the unique address @value_location, it can
80 	 * be ensured that an initialization section will be executed only once
81 	 * during a program's life time, and that concurrent threads are
82 	 * blocked until initialization completed. To be used in constructs
83 	 * like this:
84 	 *
85 	 * |[<!-- language="C" -->
86 	 * static gsize initialization_value = 0;
87 	 *
88 	 * if (g_once_init_enter (&initialization_value))
89 	 * {
90 	 * gsize setup_value = 42; // initialization code here
91 	 *
92 	 * g_once_init_leave (&initialization_value, setup_value);
93 	 * }
94 	 *
95 	 * // use initialization_value here
96 	 * ]|
97 	 *
98 	 * Params:
99 	 *     location = location of a static initializable variable
100 	 *         containing 0
101 	 *
102 	 * Returns: %TRUE if the initialization section should be entered,
103 	 *     %FALSE and blocks otherwise
104 	 *
105 	 * Since: 2.14
106 	 */
107 	public static bool initEnter(void* location)
108 	{
109 		return g_once_init_enter(location) != 0;
110 	}
111 
112 	/**
113 	 * Counterpart to g_once_init_enter(). Expects a location of a static
114 	 * 0-initialized initialization variable, and an initialization value
115 	 * other than 0. Sets the variable to the initialization value, and
116 	 * releases concurrent threads blocking in g_once_init_enter() on this
117 	 * initialization variable.
118 	 *
119 	 * Params:
120 	 *     location = location of a static initializable variable
121 	 *         containing 0
122 	 *     result = new non-0 value for *@value_location
123 	 *
124 	 * Since: 2.14
125 	 */
126 	public static void initLeave(void* location, size_t result)
127 	{
128 		g_once_init_leave(location, result);
129 	}
130 }