1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <stdlib.h> 18 #include <cutils/qsort_r_compat.h> 19 20 #if HAVE_BSD_QSORT_R 21 22 /* 23 * BSD qsort_r parameter order is as we have defined here. 24 */ 25 26 void qsort_r_compat(void* base, size_t nel, size_t width, void* thunk, 27 int (*compar)(void*, const void* , const void*)) { 28 qsort_r(base, nel, width, thunk, compar); 29 } 30 31 #elif HAVE_GNU_QSORT_R 32 33 /* 34 * GNU qsort_r parameter order places the thunk parameter last. 35 */ 36 37 struct compar_data { 38 void* thunk; 39 int (*compar)(void*, const void* , const void*); 40 }; 41 42 static int compar_wrapper(const void* a, const void* b, void* data) { 43 struct compar_data* compar_data = (struct compar_data*)data; 44 return compar_data->compar(compar_data->thunk, a, b); 45 } 46 47 void qsort_r_compat(void* base, size_t nel, size_t width, void* thunk, 48 int (*compar)(void*, const void* , const void*)) { 49 struct compar_data compar_data; 50 compar_data.thunk = thunk; 51 compar_data.compar = compar; 52 qsort_r(base, nel, width, compar_wrapper, &compar_data); 53 } 54 55 #else 56 57 /* 58 * Emulate qsort_r using thread local storage to access the thunk data. 59 */ 60 61 #include <cutils/threads.h> 62 63 static thread_store_t compar_data_key = THREAD_STORE_INITIALIZER; 64 65 struct compar_data { 66 void* thunk; 67 int (*compar)(void*, const void* , const void*); 68 }; 69 70 static int compar_wrapper(const void* a, const void* b) { 71 struct compar_data* compar_data = (struct compar_data*)thread_store_get(&compar_data_key); 72 return compar_data->compar(compar_data->thunk, a, b); 73 } 74 75 void qsort_r_compat(void* base, size_t nel, size_t width, void* thunk, 76 int (*compar)(void*, const void* , const void*)) { 77 struct compar_data compar_data; 78 compar_data.thunk = thunk; 79 compar_data.compar = compar; 80 thread_store_set(&compar_data_key, &compar_data, NULL); 81 qsort(base, nel, width, compar_wrapper); 82 } 83 84 #endif 85
