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 _GRWLock         GRWLock;
  57 typedef struct _GCond           GCond;
  58 typedef struct _GPrivate        GPrivate;
  59 typedef struct _GStaticPrivate  GStaticPrivate;
  60
  61 #ifdef G_OS_WIN32
  62
  63 #define G_MUTEX_INIT { NULL }
  64 struct _GMutex
  65 {
  66   gpointer impl;
  67 };
  68
  69 #define G_RW_LOCK_INIT { NULL }
  70 struct _GRWLock
  71 {
  72   gpointer impl;
  73 };
  74
  75 #define G_COND_INIT { NULL }
  76 struct _GCond
  77 {
  78   gpointer impl;
  79 };
  80 #else
  81
  82 #include <pthread.h>
  83
  84 #define G_MUTEX_INIT { PTHREAD_MUTEX_INITIALIZER }
  85 struct _GMutex
  86 {
  87   pthread_mutex_t impl;
  88 };
  89
  90 #define G_RW_LOCK_INIT { PTHREAD_RWLOCK_INITIALIZER }
  91 struct _GRWLock
  92 {
  93   pthread_rwlock_t impl;
  94 };
  95
  96 #define G_COND_INIT { PTHREAD_COND_INITIALIZER }
  97 struct _GCond
  98 {
  99   pthread_cond_t impl;
 100 };
 101
 102 #endif
 103
 104 /* initializes the mutex/cond/private implementation for glib, might
 105  * only be called once, and must not be called directly or indirectly
 106  * from another glib-function, e.g. as a callback.
 107  */
 108 void    g_thread_init   (gpointer vtable);
 109
 110 /* Checks if thread support is initialized.  Identical to the
 111  * g_thread_supported macro but provided for language bindings.
 112  */
 113 gboolean g_thread_get_initialized (void);
 114
 115 GLIB_VAR gboolean               g_threads_got_initialized;
 116
 117 /* internal function for fallback static mutex implementation */
 118 GMutex* g_static_mutex_get_mutex_impl   (GMutex **mutex);
 119
 120 #if defined(G_THREADS_MANDATORY)
 121 #define g_thread_supported()     1
 122 #else
 123 #define g_thread_supported()    (g_threads_got_initialized)
 124 #endif
 125
 126 GThread *g_thread_create                 (GThreadFunc   func,
 127                                           gpointer      data,
 128                                           gboolean      joinable,
 129                                           GError      **error);
 130
 131 GThread *g_thread_create_with_stack_size (GThreadFunc   func,
 132                                           gpointer      data,
 133                                           gboolean      joinable,
 134                                           gsize         stack_size,
 135                                           GError      **error);
 136
 137 GThread* g_thread_self                   (void);
 138 void     g_thread_exit                   (gpointer      retval);
 139 gpointer g_thread_join                   (GThread      *thread);
 140 void     g_thread_yield                  (void);
 141
 142 void     g_thread_foreach                (GFunc         thread_func,
 143                                           gpointer      user_data);
 144
 145 #ifdef G_OS_WIN32
 146 typedef GMutex * GStaticMutex;
 147 #define G_STATIC_MUTEX_INIT NULL
 148 #define g_static_mutex_get_mutex g_static_mutex_get_mutex_impl
 149 #else /* G_OS_WIN32 */
 150 typedef struct {
 151   struct _GMutex *unused;
 152   GMutex mutex;
 153 } GStaticMutex;
 154 #define G_STATIC_MUTEX_INIT { NULL, G_MUTEX_INIT }
 155 #define g_static_mutex_get_mutex(s) (&(s)->mutex)
 156 #endif /* G_OS_WIN32 */
 157
 158 #define g_static_mutex_lock(mutex) \
 159     g_mutex_lock (g_static_mutex_get_mutex (mutex))
 160 #define g_static_mutex_trylock(mutex) \
 161     g_mutex_trylock (g_static_mutex_get_mutex (mutex))
 162 #define g_static_mutex_unlock(mutex) \
 163     g_mutex_unlock (g_static_mutex_get_mutex (mutex))
 164 void g_static_mutex_init (GStaticMutex *mutex);
 165 void g_static_mutex_free (GStaticMutex *mutex);
 166
 167 struct _GStaticPrivate
 168 {
 169   /*< private >*/
 170   guint index;
 171 };
 172 #define G_STATIC_PRIVATE_INIT { 0 }
 173 void     g_static_private_init           (GStaticPrivate   *private_key);
 174 gpointer g_static_private_get            (GStaticPrivate   *private_key);
 175 void     g_static_private_set            (GStaticPrivate   *private_key,
 176                                           gpointer          data,
 177                                           GDestroyNotify    notify);
 178 void     g_static_private_free           (GStaticPrivate   *private_key);
 179
 180 typedef struct _GStaticRecMutex GStaticRecMutex;
 181 struct _GStaticRecMutex
 182 {
 183   /*< private >*/
 184   GStaticMutex mutex;
 185   guint depth;
 186   GSystemThread owner;
 187 };
 188
 189 #define G_STATIC_REC_MUTEX_INIT { G_STATIC_MUTEX_INIT, 0, {{0, 0, 0, 0}} }
 190 void     g_static_rec_mutex_init        (GStaticRecMutex *mutex);
 191 void     g_static_rec_mutex_lock        (GStaticRecMutex *mutex);
 192 gboolean g_static_rec_mutex_trylock     (GStaticRecMutex *mutex);
 193 void     g_static_rec_mutex_unlock      (GStaticRecMutex *mutex);
 194 void     g_static_rec_mutex_lock_full   (GStaticRecMutex *mutex,
 195                                          guint            depth);
 196 guint    g_static_rec_mutex_unlock_full (GStaticRecMutex *mutex);
 197 void     g_static_rec_mutex_free        (GStaticRecMutex *mutex);
 198
 199 typedef struct _GStaticRWLock GStaticRWLock;
 200 struct _GStaticRWLock
 201 {
 202   /*< private >*/
 203   GStaticMutex mutex;
 204   GCond *read_cond;
 205   GCond *write_cond;
 206   guint read_counter;
 207   gboolean have_writer;
 208   guint want_to_read;
 209   guint want_to_write;
 210 };
 211
 212 #define G_STATIC_RW_LOCK_INIT { G_STATIC_MUTEX_INIT, NULL, NULL, 0, FALSE, 0, 0 }
 213
 214 void      g_static_rw_lock_init           (GStaticRWLock* lock);
 215 void      g_static_rw_lock_reader_lock    (GStaticRWLock* lock);
 216 gboolean  g_static_rw_lock_reader_trylock (GStaticRWLock* lock);
 217 void      g_static_rw_lock_reader_unlock  (GStaticRWLock* lock);
 218 void      g_static_rw_lock_writer_lock    (GStaticRWLock* lock);
 219 gboolean  g_static_rw_lock_writer_trylock (GStaticRWLock* lock);
 220 void      g_static_rw_lock_writer_unlock  (GStaticRWLock* lock);
 221 void      g_static_rw_lock_free           (GStaticRWLock* lock);
 222
 223 typedef enum
 224 {
 225   G_ONCE_STATUS_NOTCALLED,
 226   G_ONCE_STATUS_PROGRESS,
 227   G_ONCE_STATUS_READY
 228 } GOnceStatus;
 229
 230 typedef struct _GOnce GOnce;
 231 struct _GOnce
 232 {
 233   volatile GOnceStatus status;
 234   volatile gpointer retval;
 235 };
 236
 237 #define G_ONCE_INIT { G_ONCE_STATUS_NOTCALLED, NULL }
 238
 239 gpointer g_once_impl (GOnce *once, GThreadFunc func, gpointer arg);
 240
 241 #ifdef G_ATOMIC_OP_MEMORY_BARRIER_NEEDED
 242 # define g_once(once, func, arg) g_once_impl ((once), (func), (arg))
 243 #else /* !G_ATOMIC_OP_MEMORY_BARRIER_NEEDED*/
 244 # define g_once(once, func, arg) \
 245   (((once)->status == G_ONCE_STATUS_READY) ? \
 246    (once)->retval : \
 247    g_once_impl ((once), (func), (arg)))
 248 #endif /* G_ATOMIC_OP_MEMORY_BARRIER_NEEDED */
 249
 250 /* initialize-once guards, keyed by value_location */
 251 G_INLINE_FUNC gboolean  g_once_init_enter       (volatile gsize *value_location);
 252 gboolean                g_once_init_enter_impl  (volatile gsize *value_location);
 253 void                    g_once_init_leave       (volatile gsize *value_location,
 254                                                  gsize           initialization_value);
 255 #if defined (G_CAN_INLINE) || defined (__G_THREAD_C__)
 256 G_INLINE_FUNC gboolean
 257 g_once_init_enter (volatile gsize *value_location)
 258 {
 259   if G_LIKELY ((gpointer) g_atomic_pointer_get (value_location) != NULL)
 260     return FALSE;
 261   else
 262     return g_once_init_enter_impl (value_location);
 263 }
 264 #endif /* G_CAN_INLINE || __G_THREAD_C__ */
 265
 266 #define G_LOCK_NAME(name)               g__ ## name ## _lock
 267 #define G_LOCK_DEFINE_STATIC(name)    static G_LOCK_DEFINE (name)
 268 #define G_LOCK_DEFINE(name)           \
 269   GMutex G_LOCK_NAME (name) = G_MUTEX_INIT
 270 #define G_LOCK_EXTERN(name)           extern GMutex G_LOCK_NAME (name)
 271
 272 #ifdef G_DEBUG_LOCKS
 273 #  define G_LOCK(name)                G_STMT_START{             \
 274       g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,                   \
 275              "file %s: line %d (%s): locking: %s ",             \
 276              __FILE__,        __LINE__, G_STRFUNC,              \
 277              #name);                                            \
 278       g_mutex_lock (&G_LOCK_NAME (name));                       \
 279    }G_STMT_END
 280 #  define G_UNLOCK(name)              G_STMT_START{             \
 281       g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,                   \
 282              "file %s: line %d (%s): unlocking: %s ",           \
 283              __FILE__,        __LINE__, G_STRFUNC,              \
 284              #name);                                            \
 285      g_mutex_unlock (&G_LOCK_NAME (name));                      \
 286    }G_STMT_END
 287 #  define G_TRYLOCK(name)                                       \
 288       (g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,                  \
 289              "file %s: line %d (%s): try locking: %s ",         \
 290              __FILE__,        __LINE__, G_STRFUNC,              \
 291              #name), g_mutex_trylock (&G_LOCK_NAME (name)))
 292 #else  /* !G_DEBUG_LOCKS */
 293 #  define G_LOCK(name) g_mutex_lock       (&G_LOCK_NAME (name))
 294 #  define G_UNLOCK(name) g_mutex_unlock   (&G_LOCK_NAME (name))
 295 #  define G_TRYLOCK(name) g_mutex_trylock (&G_LOCK_NAME (name))
 296 #endif /* !G_DEBUG_LOCKS */
 297
 298
 299 GMutex *                g_mutex_new                                     (void);
 300 void                    g_mutex_free                                    (GMutex         *mutex);
 301 void                    g_mutex_init                                    (GMutex         *mutex);
 302 void                    g_mutex_clear                                   (GMutex         *mutex);
 303
 304 void                    g_mutex_lock                                    (GMutex         *mutex);
 305 void                    g_mutex_unlock                                  (GMutex         *mutex);
 306 gboolean                g_mutex_trylock                                 (GMutex         *mutex);
 307
 308 void                    g_rw_lock_init                                  (GRWLock        *lock);
 309 void                    g_rw_lock_clear                                 (GRWLock        *lock);
 310 void                    g_rw_lock_writer_lock                           (GRWLock        *lock);
 311 gboolean                g_rw_lock_writer_trylock                        (GRWLock        *lock);
 312 void                    g_rw_lock_writer_unlock                         (GRWLock        *lock);
 313 void                    g_rw_lock_reader_lock                           (GRWLock        *lock);
 314 gboolean                g_rw_lock_reader_trylock                        (GRWLock        *lock);
 315 void                    g_rw_lock_reader_unlock                         (GRWLock        *lock);
 316
 317 GCond *                 g_cond_new                                      (void);
 318 void                    g_cond_free                                     (GCond          *cond);
 319 void                    g_cond_init                                     (GCond          *cond);
 320 void                    g_cond_clear                                    (GCond          *cond);
 321
 322 void                    g_cond_wait                                     (GCond          *cond,
 323                                                                          GMutex         *mutex);
 324 void                    g_cond_signal                                   (GCond          *cond);
 325 void                    g_cond_broadcast                                (GCond          *cond);
 326 gboolean                g_cond_timed_wait                               (GCond          *cond,
 327                                                                          GMutex         *mutex,
 328                                                                          GTimeVal       *timeval);
 329 gboolean                g_cond_timedwait                                (GCond          *cond,
 330                                                                          GMutex         *mutex,
 331                                                                          gint64          abs_time);
 332
 333 GPrivate *              g_private_new                                   (GDestroyNotify  notify);
 334 gpointer                g_private_get                                   (GPrivate       *key);
 335 void                    g_private_set                                   (GPrivate       *key,
 336                                                                          gpointer        value);
 337
 338 G_END_DECLS
 339
 340 #endif /* __G_THREAD_H__ */