1 /* 2 * Copyright (c) 2003 by Hewlett-Packard Company. All rights reserved. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a copy 5 * of this software and associated documentation files (the "Software"), to deal 6 * in the Software without restriction, including without limitation the rights 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 8 * copies of the Software, and to permit persons to whom the Software is 9 * furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 20 * SOFTWARE. 21 */ 22 23 /* 24 * Ensure, if at all possible, that AO_compare_and_swap_full() is 25 * available. The emulation should be brute-force signal-safe, even 26 * though it actually blocks. 27 * Including this file will generate an error if AO_compare_and_swap_full() 28 * cannot be made available. 29 * This will be included from platform-specific atomic_ops files 30 * if appropriate, and if AO_FORCE_CAS is defined. It should not be 31 * included directly, especially since it affects the implementation 32 * of other atomic update primitives. 33 * The implementation assumes that only AO_store_XXX and AO_test_and_set_XXX 34 * variants are defined, and that AO_test_and_set_XXX is not used to 35 * operate on compare_and_swap locations. 36 */ 37 38 #if !defined(ATOMIC_OPS_H) 39 # error This file should not be included directly. 40 #endif 41 42 #ifndef AO_HAVE_double_t 43 # include "standard_ao_double_t.h" 44 #endif 45 46 int AO_compare_and_swap_emulation(volatile AO_t *addr, AO_t old, 47 AO_t new_val); 48 49 int AO_compare_double_and_swap_double_emulation(volatile AO_double_t *addr, 50 AO_t old_val1, AO_t old_val2, 51 AO_t new_val1, AO_t new_val2); 52 53 void AO_store_full_emulation(volatile AO_t *addr, AO_t val); 54 55 #define AO_compare_and_swap_full(addr, old, newval) \ 56 AO_compare_and_swap_emulation(addr, old, newval) 57 #define AO_HAVE_compare_and_swap_full 58 59 #ifndef AO_HAVE_compare_double_and_swap_double 60 # define AO_compare_double_and_swap_double_full(addr, old1, old2, \ 61 newval1, newval2) \ 62 AO_compare_double_and_swap_double_emulation(addr, old1, old2, \ 63 newval1, newval2) 64 # define AO_HAVE_compare_double_and_swap_double_full 65 #endif 66 67 #undef AO_store 68 #undef AO_HAVE_store 69 #undef AO_store_write 70 #undef AO_HAVE_store_write 71 #undef AO_store_release 72 #undef AO_HAVE_store_release 73 #undef AO_store_full 74 #undef AO_HAVE_store_full 75 #define AO_store_full(addr, val) AO_store_full_emulation(addr, val) 76 #define AO_HAVE_store_full 77