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 = Cond 29 * strct = GCond 30 * realStrct= 31 * ctorStrct= 32 * clss = Cond 33 * interf = 34 * class Code: No 35 * interface Code: No 36 * template for: 37 * extend = 38 * implements: 39 * prefixes: 40 * - g_cond_ 41 * omit structs: 42 * omit prefixes: 43 * omit code: 44 * omit signals: 45 * imports: 46 * - gthread.Mutex 47 * structWrap: 48 * - GMutex* -> Mutex 49 * module aliases: 50 * local aliases: 51 * overrides: 52 */ 53 54 module gthread.Cond; 55 56 public import gtkc.gthreadtypes; 57 58 private import gtkc.gthread; 59 private import glib.ConstructionException; 60 61 62 private import gthread.Mutex; 63 64 65 66 67 /** 68 * Threads act almost like processes, but unlike processes all threads 69 * of one process share the same memory. This is good, as it provides 70 * easy communication between the involved threads via this shared 71 * memory, and it is bad, because strange things (so called 72 * "Heisenbugs") might happen if the program is not carefully designed. 73 * In particular, due to the concurrent nature of threads, no 74 * assumptions on the order of execution of code running in different 75 * threads can be made, unless order is explicitly forced by the 76 * programmer through synchronization primitives. 77 * 78 * The aim of the thread-related functions in GLib is to provide a 79 * portable means for writing multi-threaded software. There are 80 * primitives for mutexes to protect the access to portions of memory 81 * (GMutex, GRecMutex and GRWLock). There is a facility to use 82 * individual bits for locks (g_bit_lock()). There are primitives 83 * for condition variables to allow synchronization of threads (GCond). 84 * There are primitives for thread-private data - data that every 85 * thread has a private instance of (GPrivate). There are facilities 86 * for one-time initialization (GOnce, g_once_init_enter()). Finally, 87 * there are primitives to create and manage threads (GThread). 88 * 89 * The GLib threading system used to be initialized with g_thread_init(). 90 * This is no longer necessary. Since version 2.32, the GLib threading 91 * system is automatically initialized at the start of your program, 92 * and all thread-creation functions and synchronization primitives 93 * are available right away. 94 * 95 * Note that it is not safe to assume that your program has no threads 96 * even if you don't call g_thread_new() yourself. GLib and GIO can 97 * and will create threads for their own purposes in some cases, such 98 * as when using g_unix_signal_source_new() or when using GDBus. 99 * 100 * Originally, UNIX did not have threads, and therefore some traditional 101 * UNIX APIs are problematic in threaded programs. Some notable examples 102 * are 103 * 104 * C library functions that return data in statically allocated 105 * buffers, such as strtok() or strerror(). For many of these, 106 * there are thread-safe variants with a _r suffix, or you can 107 * look at corresponding GLib APIs (like g_strsplit() or g_strerror()). 108 * 109 * setenv() and unsetenv() manipulate the process environment in 110 * a not thread-safe way, and may interfere with getenv() calls 111 * in other threads. Note that getenv() calls may be 112 * “hidden” behind other APIs. For example, GNU gettext() 113 * calls getenv() under the covers. In general, it is best to treat 114 * the environment as readonly. If you absolutely have to modify the 115 * environment, do it early in main(), when no other threads are around yet. 116 * 117 * setlocale() changes the locale for the entire process, affecting 118 * all threads. Temporary changes to the locale are often made to 119 * change the behavior of string scanning or formatting functions 120 * like scanf() or printf(). GLib offers a number of string APIs 121 * (like g_ascii_formatd() or g_ascii_strtod()) that can often be 122 * used as an alternative. Or you can use the uselocale() function 123 * to change the locale only for the current thread. 124 * 125 * fork() only takes the calling thread into the child's copy of the 126 * process image. If other threads were executing in critical 127 * sections they could have left mutexes locked which could easily 128 * cause deadlocks in the new child. For this reason, you should 129 * call exit() or exec() as soon as possible in the child and only 130 * make signal-safe library calls before that. 131 * 132 * daemon() uses fork() in a way contrary to what is described 133 * above. It should not be used with GLib programs. 134 * 135 * GLib itself is internally completely thread-safe (all global data is 136 * automatically locked), but individual data structure instances are 137 * not automatically locked for performance reasons. For example, 138 * you must coordinate accesses to the same GHashTable from multiple 139 * threads. The two notable exceptions from this rule are GMainLoop 140 * and GAsyncQueue, which are thread-safe and 141 * need no further application-level locking to be accessed from 142 * multiple threads. Most refcounting functions such as g_object_ref() 143 * are also thread-safe. 144 */ 145 public class Cond 146 { 147 148 /** the main Gtk struct */ 149 protected GCond* gCond; 150 151 152 public GCond* getCondStruct() 153 { 154 return gCond; 155 } 156 157 158 /** the main Gtk struct as a void* */ 159 protected void* getStruct() 160 { 161 return cast(void*)gCond; 162 } 163 164 /** 165 * Sets our main struct and passes it to the parent class 166 */ 167 public this (GCond* gCond) 168 { 169 this.gCond = gCond; 170 } 171 172 /** 173 */ 174 175 /** 176 * Initialises a GCond so that it can be used. 177 * This function is useful to initialise a GCond that has been 178 * allocated as part of a larger structure. It is not necessary to 179 * initialise a GCond that has been statically allocated. 180 * To undo the effect of g_cond_init() when a GCond is no longer 181 * needed, use g_cond_clear(). 182 * Calling g_cond_init() on an already-initialised GCond leads 183 * to undefined behaviour. 184 * Since 2.32 185 */ 186 public void init() 187 { 188 // void g_cond_init (GCond *cond); 189 g_cond_init(gCond); 190 } 191 192 /** 193 * Frees the resources allocated to a GCond with g_cond_init(). 194 * This function should not be used with a GCond that has been 195 * statically allocated. 196 * Calling g_cond_clear() for a GCond on which threads are 197 * blocking leads to undefined behaviour. 198 * Since 2.32 199 */ 200 public void clear() 201 { 202 // void g_cond_clear (GCond *cond); 203 g_cond_clear(gCond); 204 } 205 206 /** 207 * Atomically releases mutex and waits until cond is signalled. 208 * When this function returns, mutex is locked again and owned by the 209 * calling thread. 210 * When using condition variables, it is possible that a spurious wakeup 211 * may occur (ie: g_cond_wait() returns even though g_cond_signal() was 212 * not called). It's also possible that a stolen wakeup may occur. 213 * This is when g_cond_signal() is called, but another thread acquires 214 * mutex before this thread and modifies the state of the program in 215 * such a way that when g_cond_wait() is able to return, the expected 216 * condition is no longer met. 217 * For this reason, g_cond_wait() must always be used in a loop. See 218 * the documentation for GCond for a complete example. 219 * Params: 220 * mutex = a GMutex that is currently locked 221 */ 222 public void wait(Mutex mutex) 223 { 224 // void g_cond_wait (GCond *cond, GMutex *mutex); 225 g_cond_wait(gCond, (mutex is null) ? null : mutex.getMutexStruct()); 226 } 227 228 /** 229 * Warning 230 * g_cond_timed_wait has been deprecated since version 2.32 and should not be used in newly-written code. Use g_cond_wait_until() instead. 231 * Waits until this thread is woken up on cond, but not longer than 232 * until the time specified by abs_time. The mutex is unlocked before 233 * falling asleep and locked again before resuming. 234 * If abs_time is NULL, g_cond_timed_wait() acts like g_cond_wait(). 235 * This function can be used even if g_thread_init() has not yet been 236 * called, and, in that case, will immediately return TRUE. 237 * To easily calculate abs_time a combination of g_get_current_time() 238 * and g_time_val_add() can be used. 239 * Params: 240 * mutex = a GMutex that is currently locked 241 * absTime = a GTimeVal, determining the final time 242 * Returns: TRUE if cond was signalled, or FALSE on timeout 243 */ 244 public int timedWait(Mutex mutex, ref GTimeVal absTime) 245 { 246 // gboolean g_cond_timed_wait (GCond *cond, GMutex *mutex, GTimeVal *abs_time); 247 return g_cond_timed_wait(gCond, (mutex is null) ? null : mutex.getMutexStruct(), &absTime); 248 } 249 250 /** 251 * Waits until either cond is signalled or end_time has passed. 252 * As with g_cond_wait() it is possible that a spurious or stolen wakeup 253 * could occur. For that reason, waiting on a condition variable should 254 * always be in a loop, based on an explicitly-checked predicate. 255 * TRUE is returned if the condition variable was signalled (or in the 256 * case of a spurious wakeup). FALSE is returned if end_time has 257 * passed. 258 * The following code shows how to correctly perform a timed wait on a 259 * condition variable (extended the example presented in the 260 * Since 2.32 261 * Params: 262 * mutex = a GMutex that is currently locked 263 * endTime = the monotonic time to wait until 264 * Returns: TRUE on a signal, FALSE on a timeout 265 */ 266 public int waitUntil(Mutex mutex, long endTime) 267 { 268 // gboolean g_cond_wait_until (GCond *cond, GMutex *mutex, gint64 end_time); 269 return g_cond_wait_until(gCond, (mutex is null) ? null : mutex.getMutexStruct(), endTime); 270 } 271 272 /** 273 * If threads are waiting for cond, at least one of them is unblocked. 274 * If no threads are waiting for cond, this function has no effect. 275 * It is good practice to hold the same lock as the waiting thread 276 * while calling this function, though not required. 277 */ 278 public void signal() 279 { 280 // void g_cond_signal (GCond *cond); 281 g_cond_signal(gCond); 282 } 283 284 /** 285 * If threads are waiting for cond, all of them are unblocked. 286 * If no threads are waiting for cond, this function has no effect. 287 * It is good practice to lock the same mutex as the waiting threads 288 * while calling this function, though not required. 289 */ 290 public void broadcast() 291 { 292 // void g_cond_broadcast (GCond *cond); 293 g_cond_broadcast(gCond); 294 } 295 }