glib/gthread.h

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GLib Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #if defined(G_DISABLE_SINGLE_INCLUDES) && !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
  28 #error "Only <glib.h> can be included directly."
  29 #endif
  30
  31 #ifndef __G_THREAD_H__
  32 #define __G_THREAD_H__
  33
  34 #include <glib/gerror.h>
  35 #include <glib/gutils.h>        /* for G_INLINE_FUNC */
  36 #include <glib/gatomic.h>       /* for g_atomic_pointer_get */
  37
  38 G_BEGIN_DECLS
  39
  40 /* GLib Thread support
  41  */
  42
  43 extern GQuark g_thread_error_quark (void);
  44 #define G_THREAD_ERROR g_thread_error_quark ()
  45
  46 typedef enum
  47 {
  48   G_THREAD_ERROR_AGAIN /* Resource temporarily unavailable */
  49 } GThreadError;
  50
  51 typedef gpointer (*GThreadFunc) (gpointer data);
  52
  53 typedef struct _GThread         GThread;
  54
  55 typedef struct _GMutex          GMutex;
  56 typedef struct _GRecMutex       GRecMutex;
  57 typedef struct _GRWLock         GRWLock;
  58 typedef struct _GCond           GCond;
  59 typedef struct _GPrivate        GPrivate;
  60 typedef struct _GStaticPrivate  GStaticPrivate;
  61
  62 #ifdef G_OS_WIN32
  63
  64 #define G_MUTEX_INIT { NULL }
  65 struct _GMutex
  66 {
  67   gpointer impl;
  68 };
  69
  70 #define G_RW_LOCK_INIT { NULL }
  71 struct _GRWLock
  72 {
  73   gpointer impl;
  74 };
  75
  76 #define G_COND_INIT { NULL }
  77 struct _GCond
  78 {
  79   gpointer impl;
  80 };
  81 #else
  82
  83 #include <pthread.h>
  84
  85 #define G_MUTEX_INIT { PTHREAD_MUTEX_INITIALIZER }
  86 struct _GMutex
  87 {
  88   pthread_mutex_t impl;
  89 };
  90
  91 #define G_RW_LOCK_INIT { PTHREAD_RWLOCK_INITIALIZER }
  92 struct _GRWLock
  93 {
  94   pthread_rwlock_t impl;
  95 };
  96
  97 #define G_COND_INIT { PTHREAD_COND_INITIALIZER }
  98 struct _GCond
  99 {
 100   pthread_cond_t impl;
 101 };
 102
 103 #endif
 104
 105 #define G_REC_MUTEX_INIT { NULL }
 106 struct _GRecMutex
 107 {
 108   gpointer impl;
 109 };
 110
 111 /* initializes the mutex/cond/private implementation for glib, might
 112  * only be called once, and must not be called directly or indirectly
 113  * from another glib-function, e.g. as a callback.
 114  */
 115 void    g_thread_init   (gpointer vtable);
 116
 117 /* Checks if thread support is initialized.  Identical to the
 118  * g_thread_supported macro but provided for language bindings.
 119  */
 120 gboolean g_thread_get_initialized (void);
 121
 122 GLIB_VAR gboolean               g_threads_got_initialized;
 123
 124 /* internal function for fallback static mutex implementation */
 125 GMutex* g_static_mutex_get_mutex_impl   (GMutex **mutex);
 126
 127 #if defined(G_THREADS_MANDATORY)
 128 #define g_thread_supported()     1
 129 #else
 130 #define g_thread_supported()    (g_threads_got_initialized)
 131 #endif
 132
 133 GThread *g_thread_create                 (GThreadFunc   func,
 134                                           gpointer      data,
 135                                           gboolean      joinable,
 136                                           GError      **error);
 137
 138 GThread *g_thread_create_with_stack_size (GThreadFunc   func,
 139                                           gpointer      data,
 140                                           gboolean      joinable,
 141                                           gsize         stack_size,
 142                                           GError      **error);
 143
 144 GThread* g_thread_self                   (void);
 145 void     g_thread_exit                   (gpointer      retval);
 146 gpointer g_thread_join                   (GThread      *thread);
 147 void     g_thread_yield                  (void);
 148
 149 void     g_thread_foreach                (GFunc         thread_func,
 150                                           gpointer      user_data);
 151
 152 #ifdef G_OS_WIN32
 153 typedef GMutex * GStaticMutex;
 154 #define G_STATIC_MUTEX_INIT NULL
 155 #define g_static_mutex_get_mutex g_static_mutex_get_mutex_impl
 156 #else /* G_OS_WIN32 */
 157 typedef struct {
 158   struct _GMutex *unused;
 159   GMutex mutex;
 160 } GStaticMutex;
 161 #define G_STATIC_MUTEX_INIT { NULL, G_MUTEX_INIT }
 162 #define g_static_mutex_get_mutex(s) (&(s)->mutex)
 163 #endif /* G_OS_WIN32 */
 164
 165 #define g_static_mutex_lock(mutex) \
 166     g_mutex_lock (g_static_mutex_get_mutex (mutex))
 167 #define g_static_mutex_trylock(mutex) \
 168     g_mutex_trylock (g_static_mutex_get_mutex (mutex))
 169 #define g_static_mutex_unlock(mutex) \
 170     g_mutex_unlock (g_static_mutex_get_mutex (mutex))
 171 void g_static_mutex_init (GStaticMutex *mutex);
 172 void g_static_mutex_free (GStaticMutex *mutex);
 173
 174 struct _GStaticPrivate
 175 {
 176   /*< private >*/
 177   guint index;
 178 };
 179 #define G_STATIC_PRIVATE_INIT { 0 }
 180 void     g_static_private_init           (GStaticPrivate   *private_key);
 181 gpointer g_static_private_get            (GStaticPrivate   *private_key);
 182 void     g_static_private_set            (GStaticPrivate   *private_key,
 183                                           gpointer          data,
 184                                           GDestroyNotify    notify);
 185 void     g_static_private_free           (GStaticPrivate   *private_key);
 186
 187 typedef struct _GStaticRecMutex GStaticRecMutex;
 188 struct _GStaticRecMutex
 189 {
 190   /*< private >*/
 191   GStaticMutex mutex;
 192   guint depth;
 193   GSystemThread owner;
 194 };
 195
 196 #define G_STATIC_REC_MUTEX_INIT { G_STATIC_MUTEX_INIT, 0, {{0, 0, 0, 0}} }
 197 void     g_static_rec_mutex_init        (GStaticRecMutex *mutex);
 198 void     g_static_rec_mutex_lock        (GStaticRecMutex *mutex);
 199 gboolean g_static_rec_mutex_trylock     (GStaticRecMutex *mutex);
 200 void     g_static_rec_mutex_unlock      (GStaticRecMutex *mutex);
 201 void     g_static_rec_mutex_lock_full   (GStaticRecMutex *mutex,
 202                                          guint            depth);
 203 guint    g_static_rec_mutex_unlock_full (GStaticRecMutex *mutex);
 204 void     g_static_rec_mutex_free        (GStaticRecMutex *mutex);
 205
 206 typedef struct _GStaticRWLock GStaticRWLock;
 207 struct _GStaticRWLock
 208 {
 209   /*< private >*/
 210   GStaticMutex mutex;
 211   GCond *read_cond;
 212   GCond *write_cond;
 213   guint read_counter;
 214   gboolean have_writer;
 215   guint want_to_read;
 216   guint want_to_write;
 217 };
 218
 219 #define G_STATIC_RW_LOCK_INIT { G_STATIC_MUTEX_INIT, NULL, NULL, 0, FALSE, 0, 0 }
 220
 221 void      g_static_rw_lock_init           (GStaticRWLock* lock);
 222 void      g_static_rw_lock_reader_lock    (GStaticRWLock* lock);
 223 gboolean  g_static_rw_lock_reader_trylock (GStaticRWLock* lock);
 224 void      g_static_rw_lock_reader_unlock  (GStaticRWLock* lock);
 225 void      g_static_rw_lock_writer_lock    (GStaticRWLock* lock);
 226 gboolean  g_static_rw_lock_writer_trylock (GStaticRWLock* lock);
 227 void      g_static_rw_lock_writer_unlock  (GStaticRWLock* lock);
 228 void      g_static_rw_lock_free           (GStaticRWLock* lock);
 229
 230 typedef enum
 231 {
 232   G_ONCE_STATUS_NOTCALLED,
 233   G_ONCE_STATUS_PROGRESS,
 234   G_ONCE_STATUS_READY
 235 } GOnceStatus;
 236
 237 typedef struct _GOnce GOnce;
 238 struct _GOnce
 239 {
 240   volatile GOnceStatus status;
 241   volatile gpointer retval;
 242 };
 243
 244 #define G_ONCE_INIT { G_ONCE_STATUS_NOTCALLED, NULL }
 245
 246 gpointer g_once_impl (GOnce *once, GThreadFunc func, gpointer arg);
 247
 248 #ifdef G_ATOMIC_OP_MEMORY_BARRIER_NEEDED
 249 # define g_once(once, func, arg) g_once_impl ((once), (func), (arg))
 250 #else /* !G_ATOMIC_OP_MEMORY_BARRIER_NEEDED*/
 251 # define g_once(once, func, arg) \
 252   (((once)->status == G_ONCE_STATUS_READY) ? \
 253    (once)->retval : \
 254    g_once_impl ((once), (func), (arg)))
 255 #endif /* G_ATOMIC_OP_MEMORY_BARRIER_NEEDED */
 256
 257 /* initialize-once guards, keyed by value_location */
 258 G_INLINE_FUNC gboolean  g_once_init_enter       (volatile gsize *value_location);
 259 gboolean                g_once_init_enter_impl  (volatile gsize *value_location);
 260 void                    g_once_init_leave       (volatile gsize *value_location,
 261                                                  gsize           initialization_value);
 262 #if defined (G_CAN_INLINE) || defined (__G_THREAD_C__)
 263 G_INLINE_FUNC gboolean
 264 g_once_init_enter (volatile gsize *value_location)
 265 {
 266   if G_LIKELY ((gpointer) g_atomic_pointer_get (value_location) != NULL)
 267     return FALSE;
 268   else
 269     return g_once_init_enter_impl (value_location);
 270 }
 271 #endif /* G_CAN_INLINE || __G_THREAD_C__ */
 272
 273 #define G_LOCK_NAME(name)               g__ ## name ## _lock
 274 #define G_LOCK_DEFINE_STATIC(name)    static G_LOCK_DEFINE (name)
 275 #define G_LOCK_DEFINE(name)           \
 276   GMutex G_LOCK_NAME (name) = G_MUTEX_INIT
 277 #define G_LOCK_EXTERN(name)           extern GMutex G_LOCK_NAME (name)
 278
 279 #ifdef G_DEBUG_LOCKS
 280 #  define G_LOCK(name)                G_STMT_START{             \
 281       g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,                   \
 282              "file %s: line %d (%s): locking: %s ",             \
 283              __FILE__,        __LINE__, G_STRFUNC,              \
 284              #name);                                            \
 285       g_mutex_lock (&G_LOCK_NAME (name));                       \
 286    }G_STMT_END
 287 #  define G_UNLOCK(name)              G_STMT_START{             \
 288       g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,                   \
 289              "file %s: line %d (%s): unlocking: %s ",           \
 290              __FILE__,        __LINE__, G_STRFUNC,              \
 291              #name);                                            \
 292      g_mutex_unlock (&G_LOCK_NAME (name));                      \
 293    }G_STMT_END
 294 #  define G_TRYLOCK(name)                                       \
 295       (g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,                  \
 296              "file %s: line %d (%s): try locking: %s ",         \
 297              __FILE__,        __LINE__, G_STRFUNC,              \
 298              #name), g_mutex_trylock (&G_LOCK_NAME (name)))
 299 #else  /* !G_DEBUG_LOCKS */
 300 #  define G_LOCK(name) g_mutex_lock       (&G_LOCK_NAME (name))
 301 #  define G_UNLOCK(name) g_mutex_unlock   (&G_LOCK_NAME (name))
 302 #  define G_TRYLOCK(name) g_mutex_trylock (&G_LOCK_NAME (name))
 303 #endif /* !G_DEBUG_LOCKS */
 304
 305
 306 GMutex *                g_mutex_new                                     (void);
 307 void                    g_mutex_free                                    (GMutex         *mutex);
 308 void                    g_mutex_init                                    (GMutex         *mutex);
 309 void                    g_mutex_clear                                   (GMutex         *mutex);
 310
 311 void                    g_mutex_lock                                    (GMutex         *mutex);
 312 void                    g_mutex_unlock                                  (GMutex         *mutex);
 313 gboolean                g_mutex_trylock                                 (GMutex         *mutex);
 314
 315 void                    g_rw_lock_init                                  (GRWLock        *lock);
 316 void                    g_rw_lock_clear                                 (GRWLock        *lock);
 317 void                    g_rw_lock_writer_lock                           (GRWLock        *lock);
 318 gboolean                g_rw_lock_writer_trylock                        (GRWLock        *lock);
 319 void                    g_rw_lock_writer_unlock                         (GRWLock        *lock);
 320 void                    g_rw_lock_reader_lock                           (GRWLock        *lock);
 321 gboolean                g_rw_lock_reader_trylock                        (GRWLock        *lock);
 322 void                    g_rw_lock_reader_unlock                         (GRWLock        *lock);
 323
 324 void                    g_rec_mutex_init                                (GRecMutex      *rec_mutex);
 325 void                    g_rec_mutex_clear                               (GRecMutex      *rec_mutex);
 326 void                    g_rec_mutex_lock                                (GRecMutex      *rec_mutex);
 327 gboolean                g_rec_mutex_trylock                             (GRecMutex      *rec_mutex);
 328 void                    g_rec_mutex_unlock                              (GRecMutex      *rec_mutex);
 329
 330 GCond *                 g_cond_new                                      (void);
 331 void                    g_cond_free                                     (GCond          *cond);
 332 void                    g_cond_init                                     (GCond          *cond);
 333 void                    g_cond_clear                                    (GCond          *cond);
 334
 335 void                    g_cond_wait                                     (GCond          *cond,
 336                                                                          GMutex         *mutex);
 337 void                    g_cond_signal                                   (GCond          *cond);
 338 void                    g_cond_broadcast                                (GCond          *cond);
 339 gboolean                g_cond_timed_wait                               (GCond          *cond,
 340                                                                          GMutex         *mutex,
 341                                                                          GTimeVal       *timeval);
 342 gboolean                g_cond_timedwait                                (GCond          *cond,
 343                                                                          GMutex         *mutex,
 344                                                                          gint64          abs_time);
 345
 346 GPrivate *              g_private_new                                   (GDestroyNotify  notify);
 347 gpointer                g_private_get                                   (GPrivate       *key);
 348 void                    g_private_set                                   (GPrivate       *key,
 349                                                                          gpointer        value);
 350
 351 G_END_DECLS
 352
 353 #endif /* __G_THREAD_H__ */