glib/gatomic.h

   1 /*
   2  * Copyright © 2011 Ryan Lortie
   3  *
   4  * This library is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * licence, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful, but
  10  * 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, see <http://www.gnu.org/licenses/>.
  16  *
  17  * Author: Ryan Lortie <desrt@desrt.ca>
  18  */
  19
  20 #ifndef __G_ATOMIC_H__
  21 #define __G_ATOMIC_H__
  22
  23 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
  24 #error "Only <glib.h> can be included directly."
  25 #endif
  26
  27 #include <glib/gtypes.h>
  28
  29 G_BEGIN_DECLS
  30
  31 GLIB_AVAILABLE_IN_ALL
  32 gint                    g_atomic_int_get                      (const volatile gint *atomic);
  33 GLIB_AVAILABLE_IN_ALL
  34 void                    g_atomic_int_set                      (volatile gint  *atomic,
  35                                                                gint            newval);
  36 GLIB_AVAILABLE_IN_ALL
  37 void                    g_atomic_int_inc                      (volatile gint  *atomic);
  38 GLIB_AVAILABLE_IN_ALL
  39 gboolean                g_atomic_int_dec_and_test             (volatile gint  *atomic);
  40 GLIB_AVAILABLE_IN_ALL
  41 gboolean                g_atomic_int_compare_and_exchange     (volatile gint  *atomic,
  42                                                                gint            oldval,
  43                                                                gint            newval);
  44 GLIB_AVAILABLE_IN_ALL
  45 gint                    g_atomic_int_add                      (volatile gint  *atomic,
  46                                                                gint            val);
  47 GLIB_AVAILABLE_IN_2_30
  48 guint                   g_atomic_int_and                      (volatile guint *atomic,
  49                                                                guint           val);
  50 GLIB_AVAILABLE_IN_2_30
  51 guint                   g_atomic_int_or                       (volatile guint *atomic,
  52                                                                guint           val);
  53 GLIB_AVAILABLE_IN_ALL
  54 guint                   g_atomic_int_xor                      (volatile guint *atomic,
  55                                                                guint           val);
  56
  57 GLIB_AVAILABLE_IN_ALL
  58 gpointer                g_atomic_pointer_get                  (const volatile void *atomic);
  59 GLIB_AVAILABLE_IN_ALL
  60 void                    g_atomic_pointer_set                  (volatile void  *atomic,
  61                                                                gpointer        newval);
  62 GLIB_AVAILABLE_IN_ALL
  63 gboolean                g_atomic_pointer_compare_and_exchange (volatile void  *atomic,
  64                                                                gpointer        oldval,
  65                                                                gpointer        newval);
  66 GLIB_AVAILABLE_IN_ALL
  67 gssize                  g_atomic_pointer_add                  (volatile void  *atomic,
  68                                                                gssize          val);
  69 GLIB_AVAILABLE_IN_2_30
  70 gsize                   g_atomic_pointer_and                  (volatile void  *atomic,
  71                                                                gsize           val);
  72 GLIB_AVAILABLE_IN_2_30
  73 gsize                   g_atomic_pointer_or                   (volatile void  *atomic,
  74                                                                gsize           val);
  75 GLIB_AVAILABLE_IN_ALL
  76 gsize                   g_atomic_pointer_xor                  (volatile void  *atomic,
  77                                                                gsize           val);
  78
  79 GLIB_DEPRECATED_IN_2_30_FOR(g_atomic_int_add)
  80 gint                    g_atomic_int_exchange_and_add         (volatile gint  *atomic,
  81                                                                gint            val);
  82
  83 G_END_DECLS
  84
  85 #if defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
  86
  87 /* We prefer the new C11-style atomic extension of GCC if available */
  88 #if defined(__ATOMIC_SEQ_CST) && !defined(__clang__)
  89
  90 /* We use __atomic_load_4, so we rely on this being true */
  91 G_STATIC_ASSERT (sizeof (gint) == 4);
  92
  93 #define g_atomic_int_get(atomic) \
  94   (G_GNUC_EXTENSION ({                                                       \
  95     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
  96     (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
  97     (gint) __atomic_load_4 ((atomic), __ATOMIC_SEQ_CST);                     \
  98   }))
  99 #define g_atomic_int_set(atomic, newval) \
 100   (G_GNUC_EXTENSION ({                                                       \
 101     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 102     (void) (0 ? *(atomic) ^ (newval) : 0);                                   \
 103     __atomic_store_4 ((atomic), (newval), __ATOMIC_SEQ_CST);                 \
 104   }))
 105
 106 #if GLIB_SIZEOF_VOID_P == 8
 107
 108 #define g_atomic_pointer_get(atomic) \
 109   (G_GNUC_EXTENSION ({                                                       \
 110     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 111     (gpointer) __atomic_load_8 ((atomic), __ATOMIC_SEQ_CST);                 \
 112   }))
 113 #define g_atomic_pointer_set(atomic, newval) \
 114   (G_GNUC_EXTENSION ({                                                       \
 115     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 116     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 117     __atomic_store_8 ((atomic), (gsize) (newval), __ATOMIC_SEQ_CST);         \
 118   }))
 119
 120 #else /* GLIB_SIZEOF_VOID_P == 8 */
 121
 122 /* Assume that if GLIB_SIZEOF_VOID_P is not 8, it must be 4 */
 123 G_STATIC_ASSERT (sizeof (gpointer) == 4);
 124
 125 #define g_atomic_pointer_get(atomic) \
 126   (G_GNUC_EXTENSION ({                                                       \
 127     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 128     (gpointer) __atomic_load_4 ((atomic), __ATOMIC_SEQ_CST);                 \
 129   }))
 130 #define g_atomic_pointer_set(atomic, newval) \
 131   (G_GNUC_EXTENSION ({                                                       \
 132     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 133     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 134     __atomic_store_4 ((atomic), (gsize) (newval), __ATOMIC_SEQ_CST);         \
 135   }))
 136
 137 #endif /* GLIB_SIZEOF_VOID_P == 8 */
 138
 139 #else /* defined(__ATOMIC_SEQ_CST) */
 140
 141 #define g_atomic_int_get(atomic) \
 142   (G_GNUC_EXTENSION ({                                                       \
 143     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 144     (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
 145     __sync_synchronize ();                                                   \
 146     (gint) *(atomic);                                                        \
 147   }))
 148 #define g_atomic_int_set(atomic, newval) \
 149   (G_GNUC_EXTENSION ({                                                       \
 150     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 151     (void) (0 ? *(atomic) ^ (newval) : 0);                                   \
 152     *(atomic) = (newval);                                                    \
 153     __sync_synchronize ();                                                   \
 154   }))
 155 #define g_atomic_pointer_get(atomic) \
 156   (G_GNUC_EXTENSION ({                                                       \
 157     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 158     __sync_synchronize ();                                                   \
 159     (gpointer) *(atomic);                                                    \
 160   }))
 161 #define g_atomic_pointer_set(atomic, newval) \
 162   (G_GNUC_EXTENSION ({                                                       \
 163     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 164     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 165     *(atomic) = (__typeof__ (*(atomic))) (gsize) (newval);                   \
 166     __sync_synchronize ();                                                   \
 167   }))
 168
 169 #endif /* !defined(__ATOMIC_SEQ_CST) */
 170
 171 #define g_atomic_int_inc(atomic) \
 172   (G_GNUC_EXTENSION ({                                                       \
 173     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 174     (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
 175     (void) __sync_fetch_and_add ((atomic), 1);                               \
 176   }))
 177 #define g_atomic_int_dec_and_test(atomic) \
 178   (G_GNUC_EXTENSION ({                                                       \
 179     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 180     (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
 181     __sync_fetch_and_sub ((atomic), 1) == 1;                                 \
 182   }))
 183 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
 184   (G_GNUC_EXTENSION ({                                                       \
 185     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 186     (void) (0 ? *(atomic) ^ (newval) ^ (oldval) : 0);                        \
 187     (gboolean) __sync_bool_compare_and_swap ((atomic), (oldval), (newval));  \
 188   }))
 189 #define g_atomic_int_add(atomic, val) \
 190   (G_GNUC_EXTENSION ({                                                       \
 191     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 192     (void) (0 ? *(atomic) ^ (val) : 0);                                      \
 193     (gint) __sync_fetch_and_add ((atomic), (val));                           \
 194   }))
 195 #define g_atomic_int_and(atomic, val) \
 196   (G_GNUC_EXTENSION ({                                                       \
 197     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 198     (void) (0 ? *(atomic) ^ (val) : 0);                                      \
 199     (guint) __sync_fetch_and_and ((atomic), (val));                          \
 200   }))
 201 #define g_atomic_int_or(atomic, val) \
 202   (G_GNUC_EXTENSION ({                                                       \
 203     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 204     (void) (0 ? *(atomic) ^ (val) : 0);                                      \
 205     (guint) __sync_fetch_and_or ((atomic), (val));                           \
 206   }))
 207 #define g_atomic_int_xor(atomic, val) \
 208   (G_GNUC_EXTENSION ({                                                       \
 209     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 210     (void) (0 ? *(atomic) ^ (val) : 0);                                      \
 211     (guint) __sync_fetch_and_xor ((atomic), (val));                          \
 212   }))
 213
 214 #define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
 215   (G_GNUC_EXTENSION ({                                                       \
 216     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 217     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 218     (gboolean) __sync_bool_compare_and_swap ((atomic), (oldval), (newval));  \
 219   }))
 220 #define g_atomic_pointer_add(atomic, val) \
 221   (G_GNUC_EXTENSION ({                                                       \
 222     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 223     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 224     (void) (0 ? (val) ^ (val) : 0);                                          \
 225     (gssize) __sync_fetch_and_add ((atomic), (val));                         \
 226   }))
 227 #define g_atomic_pointer_and(atomic, val) \
 228   (G_GNUC_EXTENSION ({                                                       \
 229     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 230     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 231     (void) (0 ? (val) ^ (val) : 0);                                          \
 232     (gsize) __sync_fetch_and_and ((atomic), (val));                          \
 233   }))
 234 #define g_atomic_pointer_or(atomic, val) \
 235   (G_GNUC_EXTENSION ({                                                       \
 236     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 237     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 238     (void) (0 ? (val) ^ (val) : 0);                                          \
 239     (gsize) __sync_fetch_and_or ((atomic), (val));                           \
 240   }))
 241 #define g_atomic_pointer_xor(atomic, val) \
 242   (G_GNUC_EXTENSION ({                                                       \
 243     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 244     (void) (0 ? (gpointer) *(atomic) : 0);                                   \
 245     (void) (0 ? (val) ^ (val) : 0);                                          \
 246     (gsize) __sync_fetch_and_xor ((atomic), (val));                          \
 247   }))
 248
 249 #else /* defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) */
 250
 251 #define g_atomic_int_get(atomic) \
 252   (g_atomic_int_get ((gint *) (atomic)))
 253 #define g_atomic_int_set(atomic, newval) \
 254   (g_atomic_int_set ((gint *) (atomic), (gint) (newval)))
 255 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
 256   (g_atomic_int_compare_and_exchange ((gint *) (atomic), (oldval), (newval)))
 257 #define g_atomic_int_add(atomic, val) \
 258   (g_atomic_int_add ((gint *) (atomic), (val)))
 259 #define g_atomic_int_and(atomic, val) \
 260   (g_atomic_int_and ((guint *) (atomic), (val)))
 261 #define g_atomic_int_or(atomic, val) \
 262   (g_atomic_int_or ((guint *) (atomic), (val)))
 263 #define g_atomic_int_xor(atomic, val) \
 264   (g_atomic_int_xor ((guint *) (atomic), (val)))
 265 #define g_atomic_int_inc(atomic) \
 266   (g_atomic_int_inc ((gint *) (atomic)))
 267 #define g_atomic_int_dec_and_test(atomic) \
 268   (g_atomic_int_dec_and_test ((gint *) (atomic)))
 269
 270 #define g_atomic_pointer_get(atomic) \
 271   (g_atomic_pointer_get (atomic))
 272 #define g_atomic_pointer_set(atomic, newval) \
 273   (g_atomic_pointer_set ((atomic), (gpointer) (newval)))
 274 #define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
 275   (g_atomic_pointer_compare_and_exchange ((atomic), (gpointer) (oldval), (gpointer) (newval)))
 276 #define g_atomic_pointer_add(atomic, val) \
 277   (g_atomic_pointer_add ((atomic), (gssize) (val)))
 278 #define g_atomic_pointer_and(atomic, val) \
 279   (g_atomic_pointer_and ((atomic), (gsize) (val)))
 280 #define g_atomic_pointer_or(atomic, val) \
 281   (g_atomic_pointer_or ((atomic), (gsize) (val)))
 282 #define g_atomic_pointer_xor(atomic, val) \
 283   (g_atomic_pointer_xor ((atomic), (gsize) (val)))
 284
 285 #endif /* defined(__GNUC__) && defined(G_ATOMIC_OP_USE_GCC_BUILTINS) */
 286
 287 #endif /* __G_ATOMIC_H__ */