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 * Conversion parameters: 26 * inFile = 27 * outPack = gthread 28 * outFile = Once 29 * strct = GOnce 30 * realStrct= 31 * ctorStrct= 32 * clss = Once 33 * interf = 34 * class Code: No 35 * interface Code: No 36 * template for: 37 * extend = 38 * implements: 39 * prefixes: 40 * - g_once_ 41 * omit structs: 42 * omit prefixes: 43 * omit code: 44 * omit signals: 45 * imports: 46 * structWrap: 47 * module aliases: 48 * local aliases: 49 * overrides: 50 */ 51 52 module gthread.Once; 53 54 public import gtkc.gthreadtypes; 55 56 private import gtkc.gthread; 57 private import glib.ConstructionException; 58 59 60 61 62 /** 63 * Threads act almost like processes, but unlike processes all threads 64 * of one process share the same memory. This is good, as it provides 65 * easy communication between the involved threads via this shared 66 * memory, and it is bad, because strange things (so called 67 * "Heisenbugs") might happen if the program is not carefully designed. 68 * In particular, due to the concurrent nature of threads, no 69 * assumptions on the order of execution of code running in different 70 * threads can be made, unless order is explicitly forced by the 71 * programmer through synchronization primitives. 72 * 73 * The aim of the thread-related functions in GLib is to provide a 74 * portable means for writing multi-threaded software. There are 75 * primitives for mutexes to protect the access to portions of memory 76 * (GMutex, GRecMutex and GRWLock). There is a facility to use 77 * individual bits for locks (g_bit_lock()). There are primitives 78 * for condition variables to allow synchronization of threads (GCond). 79 * There are primitives for thread-private data - data that every 80 * thread has a private instance of (GPrivate). There are facilities 81 * for one-time initialization (GOnce, g_once_init_enter()). Finally, 82 * there are primitives to create and manage threads (GThread). 83 * 84 * The GLib threading system used to be initialized with g_thread_init(). 85 * This is no longer necessary. Since version 2.32, the GLib threading 86 * system is automatically initialized at the start of your program, 87 * and all thread-creation functions and synchronization primitives 88 * are available right away. 89 * 90 * Note that it is not safe to assume that your program has no threads 91 * even if you don't call g_thread_new() yourself. GLib and GIO can 92 * and will create threads for their own purposes in some cases, such 93 * as when using g_unix_signal_source_new() or when using GDBus. 94 * 95 * Originally, UNIX did not have threads, and therefore some traditional 96 * UNIX APIs are problematic in threaded programs. Some notable examples 97 * are 98 * 99 * C library functions that return data in statically allocated 100 * buffers, such as strtok() or strerror(). For many of these, 101 * there are thread-safe variants with a _r suffix, or you can 102 * look at corresponding GLib APIs (like g_strsplit() or g_strerror()). 103 * 104 * setenv() and unsetenv() manipulate the process environment in 105 * a not thread-safe way, and may interfere with getenv() calls 106 * in other threads. Note that getenv() calls may be 107 * “hidden” behind other APIs. For example, GNU gettext() 108 * calls getenv() under the covers. In general, it is best to treat 109 * the environment as readonly. If you absolutely have to modify the 110 * environment, do it early in main(), when no other threads are around yet. 111 * 112 * setlocale() changes the locale for the entire process, affecting 113 * all threads. Temporary changes to the locale are often made to 114 * change the behavior of string scanning or formatting functions 115 * like scanf() or printf(). GLib offers a number of string APIs 116 * (like g_ascii_formatd() or g_ascii_strtod()) that can often be 117 * used as an alternative. Or you can use the uselocale() function 118 * to change the locale only for the current thread. 119 * 120 * fork() only takes the calling thread into the child's copy of the 121 * process image. If other threads were executing in critical 122 * sections they could have left mutexes locked which could easily 123 * cause deadlocks in the new child. For this reason, you should 124 * call exit() or exec() as soon as possible in the child and only 125 * make signal-safe library calls before that. 126 * 127 * daemon() uses fork() in a way contrary to what is described 128 * above. It should not be used with GLib programs. 129 * 130 * GLib itself is internally completely thread-safe (all global data is 131 * automatically locked), but individual data structure instances are 132 * not automatically locked for performance reasons. For example, 133 * you must coordinate accesses to the same GHashTable from multiple 134 * threads. The two notable exceptions from this rule are GMainLoop 135 * and GAsyncQueue, which are thread-safe and 136 * need no further application-level locking to be accessed from 137 * multiple threads. Most refcounting functions such as g_object_ref() 138 * are also thread-safe. 139 */ 140 public class Once 141 { 142 143 /** the main Gtk struct */ 144 protected GOnce* gOnce; 145 146 147 /** Get the main Gtk struct */ 148 public GOnce* getOnceStruct() 149 { 150 return gOnce; 151 } 152 153 154 /** the main Gtk struct as a void* */ 155 protected void* getStruct() 156 { 157 return cast(void*)gOnce; 158 } 159 160 /** 161 * Sets our main struct and passes it to the parent class 162 */ 163 public this (GOnce* gOnce) 164 { 165 this.gOnce = gOnce; 166 } 167 168 /** 169 */ 170 171 /** 172 * Function to be called when starting a critical initialization 173 * section. The argument location must point to a static 174 * 0-initialized variable that will be set to a value other than 0 at 175 * the end of the initialization section. In combination with 176 * g_once_init_leave() and the unique address value_location, it can 177 * be ensured that an initialization section will be executed only once 178 * during a program's life time, and that concurrent threads are 179 * blocked until initialization completed. To be used in constructs 180 * Since 2.14 181 * Params: 182 * location = location of a static initializable variable containing 0 183 * Returns: TRUE if the initialization section should be entered, FALSE and blocks otherwise 184 */ 185 public static int initEnter(void* location) 186 { 187 // gboolean g_once_init_enter (volatile void *location); 188 return g_once_init_enter(location); 189 } 190 191 /** 192 * Counterpart to g_once_init_enter(). Expects a location of a static 193 * 0-initialized initialization variable, and an initialization value 194 * other than 0. Sets the variable to the initialization value, and 195 * releases concurrent threads blocking in g_once_init_enter() on this 196 * initialization variable. 197 * Since 2.14 198 * Params: 199 * location = location of a static initializable variable containing 0 200 * result = new non-0 value for *value_location 201 */ 202 public static void initLeave(void* location, gsize result) 203 { 204 // void g_once_init_leave (volatile void *location, gsize result); 205 g_once_init_leave(location, result); 206 } 207 }