Jeff Brown | 4a6b384 | 2012-03-19 14:07:26 -0700 | [diff] [blame] | 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 |