glib/gatomic.h

   1 /*
   2  * Copyright © 2011 Ryan Lortie
   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 2.1 of the License, 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 /* This assumes sizeof(int) is 4: gatomic.c statically
  91  * asserts that (using G_STATIC_ASSERT at top-level in a header was
  92  * problematic, see #730932) */
  93
  94 #define g_atomic_int_get(atomic) \
  95   (G_GNUC_EXTENSION ({                                                       \
  96     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
  97     (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
  98     (gint) __atomic_load_4 ((atomic), __ATOMIC_SEQ_CST);                     \
  99   }))
 100 #define g_atomic_int_set(atomic, newval) \
 101   (G_GNUC_EXTENSION ({                                                       \
 102     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 103     (void) (0 ? *(atomic) ^ (newval) : 1);                                   \
 104     __atomic_store_4 ((atomic), (newval), __ATOMIC_SEQ_CST);                 \
 105   }))
 106
 107 #if GLIB_SIZEOF_VOID_P == 8
 108
 109 #define g_atomic_pointer_get(atomic) \
 110   (G_GNUC_EXTENSION ({                                                       \
 111     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 112     guint64 gapg_temp = __atomic_load_8 ((atomic), __ATOMIC_SEQ_CST);        \
 113     (gpointer) gapg_temp;                                                    \
 114   }))
 115 #define g_atomic_pointer_set(atomic, newval) \
 116   (G_GNUC_EXTENSION ({                                                       \
 117     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 118     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 119     __atomic_store_8 ((atomic), (gsize) (newval), __ATOMIC_SEQ_CST);         \
 120   }))
 121
 122 #else /* GLIB_SIZEOF_VOID_P == 8 */
 123
 124 /* This assumes that if sizeof(void *) is not 8, then it is 4:
 125  * gatomic.c statically asserts that (using G_STATIC_ASSERT
 126  * at top-level in a header was problematic, see #730932) */
 127
 128 #define g_atomic_pointer_get(atomic) \
 129   (G_GNUC_EXTENSION ({                                                       \
 130     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 131     guint32 gapg_temp = __atomic_load_4 ((atomic), __ATOMIC_SEQ_CST);        \
 132     (gpointer) gapg_temp;                                                    \
 133   }))
 134 #define g_atomic_pointer_set(atomic, newval) \
 135   (G_GNUC_EXTENSION ({                                                       \
 136     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 137     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 138     __atomic_store_4 ((atomic), (gsize) (newval), __ATOMIC_SEQ_CST);         \
 139   }))
 140
 141 #endif /* GLIB_SIZEOF_VOID_P == 8 */
 142
 143 #else /* defined(__ATOMIC_SEQ_CST) */
 144
 145 #define g_atomic_int_get(atomic) \
 146   (G_GNUC_EXTENSION ({                                                       \
 147     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 148     (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
 149     __sync_synchronize ();                                                   \
 150     (gint) *(atomic);                                                        \
 151   }))
 152 #define g_atomic_int_set(atomic, newval) \
 153   (G_GNUC_EXTENSION ({                                                       \
 154     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 155     (void) (0 ? *(atomic) ^ (newval) : 1);                                   \
 156     *(atomic) = (newval);                                                    \
 157     __sync_synchronize ();                                                   \
 158   }))
 159 #define g_atomic_pointer_get(atomic) \
 160   (G_GNUC_EXTENSION ({                                                       \
 161     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 162     __sync_synchronize ();                                                   \
 163     (gpointer) *(atomic);                                                    \
 164   }))
 165 #define g_atomic_pointer_set(atomic, newval) \
 166   (G_GNUC_EXTENSION ({                                                       \
 167     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 168     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 169     *(atomic) = (__typeof__ (*(atomic))) (gsize) (newval);                   \
 170     __sync_synchronize ();                                                   \
 171   }))
 172
 173 #endif /* !defined(__ATOMIC_SEQ_CST) */
 174
 175 #define g_atomic_int_inc(atomic) \
 176   (G_GNUC_EXTENSION ({                                                       \
 177     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 178     (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
 179     (void) __sync_fetch_and_add ((atomic), 1);                               \
 180   }))
 181 #define g_atomic_int_dec_and_test(atomic) \
 182   (G_GNUC_EXTENSION ({                                                       \
 183     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 184     (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
 185     __sync_fetch_and_sub ((atomic), 1) == 1;                                 \
 186   }))
 187 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
 188   (G_GNUC_EXTENSION ({                                                       \
 189     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 190     (void) (0 ? *(atomic) ^ (newval) ^ (oldval) : 1);                        \
 191     __sync_bool_compare_and_swap ((atomic), (oldval), (newval)) ? TRUE : FALSE; \
 192   }))
 193 #define g_atomic_int_add(atomic, val) \
 194   (G_GNUC_EXTENSION ({                                                       \
 195     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 196     (void) (0 ? *(atomic) ^ (val) : 1);                                      \
 197     (gint) __sync_fetch_and_add ((atomic), (val));                           \
 198   }))
 199 #define g_atomic_int_and(atomic, val) \
 200   (G_GNUC_EXTENSION ({                                                       \
 201     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 202     (void) (0 ? *(atomic) ^ (val) : 1);                                      \
 203     (guint) __sync_fetch_and_and ((atomic), (val));                          \
 204   }))
 205 #define g_atomic_int_or(atomic, val) \
 206   (G_GNUC_EXTENSION ({                                                       \
 207     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 208     (void) (0 ? *(atomic) ^ (val) : 1);                                      \
 209     (guint) __sync_fetch_and_or ((atomic), (val));                           \
 210   }))
 211 #define g_atomic_int_xor(atomic, val) \
 212   (G_GNUC_EXTENSION ({                                                       \
 213     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
 214     (void) (0 ? *(atomic) ^ (val) : 1);                                      \
 215     (guint) __sync_fetch_and_xor ((atomic), (val));                          \
 216   }))
 217
 218 #define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
 219   (G_GNUC_EXTENSION ({                                                       \
 220     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 221     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 222     __sync_bool_compare_and_swap ((atomic), (oldval), (newval)) ? TRUE : FALSE; \
 223   }))
 224 #define g_atomic_pointer_add(atomic, val) \
 225   (G_GNUC_EXTENSION ({                                                       \
 226     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 227     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 228     (void) (0 ? (val) ^ (val) : 1);                                          \
 229     (gssize) __sync_fetch_and_add ((atomic), (val));                         \
 230   }))
 231 #define g_atomic_pointer_and(atomic, val) \
 232   (G_GNUC_EXTENSION ({                                                       \
 233     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 234     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 235     (void) (0 ? (val) ^ (val) : 1);                                          \
 236     (gsize) __sync_fetch_and_and ((atomic), (val));                          \
 237   }))
 238 #define g_atomic_pointer_or(atomic, val) \
 239   (G_GNUC_EXTENSION ({                                                       \
 240     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 241     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 242     (void) (0 ? (val) ^ (val) : 1);                                          \
 243     (gsize) __sync_fetch_and_or ((atomic), (val));                           \
 244   }))
 245 #define g_atomic_pointer_xor(atomic, val) \
 246   (G_GNUC_EXTENSION ({                                                       \
 247     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
 248     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
 249     (void) (0 ? (val) ^ (val) : 1);                                          \
 250     (gsize) __sync_fetch_and_xor ((atomic), (val));                          \
 251   }))
 252
 253 #else /* defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) */
 254
 255 #define g_atomic_int_get(atomic) \
 256   (g_atomic_int_get ((gint *) (atomic)))
 257 #define g_atomic_int_set(atomic, newval) \
 258   (g_atomic_int_set ((gint *) (atomic), (gint) (newval)))
 259 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
 260   (g_atomic_int_compare_and_exchange ((gint *) (atomic), (oldval), (newval)))
 261 #define g_atomic_int_add(atomic, val) \
 262   (g_atomic_int_add ((gint *) (atomic), (val)))
 263 #define g_atomic_int_and(atomic, val) \
 264   (g_atomic_int_and ((guint *) (atomic), (val)))
 265 #define g_atomic_int_or(atomic, val) \
 266   (g_atomic_int_or ((guint *) (atomic), (val)))
 267 #define g_atomic_int_xor(atomic, val) \
 268   (g_atomic_int_xor ((guint *) (atomic), (val)))
 269 #define g_atomic_int_inc(atomic) \
 270   (g_atomic_int_inc ((gint *) (atomic)))
 271 #define g_atomic_int_dec_and_test(atomic) \
 272   (g_atomic_int_dec_and_test ((gint *) (atomic)))
 273
 274 #define g_atomic_pointer_get(atomic) \
 275   (g_atomic_pointer_get (atomic))
 276 #define g_atomic_pointer_set(atomic, newval) \
 277   (g_atomic_pointer_set ((atomic), (gpointer) (newval)))
 278 #define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
 279   (g_atomic_pointer_compare_and_exchange ((atomic), (gpointer) (oldval), (gpointer) (newval)))
 280 #define g_atomic_pointer_add(atomic, val) \
 281   (g_atomic_pointer_add ((atomic), (gssize) (val)))
 282 #define g_atomic_pointer_and(atomic, val) \
 283   (g_atomic_pointer_and ((atomic), (gsize) (val)))
 284 #define g_atomic_pointer_or(atomic, val) \
 285   (g_atomic_pointer_or ((atomic), (gsize) (val)))
 286 #define g_atomic_pointer_xor(atomic, val) \
 287   (g_atomic_pointer_xor ((atomic), (gsize) (val)))
 288
 289 #endif /* defined(__GNUC__) && defined(G_ATOMIC_OP_USE_GCC_BUILTINS) */
 290
 291 #endif /* __G_ATOMIC_H__ */