| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* Copyright (C) 2002, 2003 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, write to the Free |
| 17 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 18 | 02111-1307 USA. */ |
| 19 | |
| 20 | #include <stdlib.h> |
| 21 | #include "pthreadP.h" |
| 22 | |
| 23 | |
| 24 | void * |
| 25 | attribute_protected |
| 26 | __pthread_getspecific (pthread_key_t key) |
| 27 | { |
| 28 | struct pthread_key_data *data; |
| 29 | |
| 30 | /* Special case access to the first 2nd-level block. This is the |
| 31 | usual case. */ |
| 32 | if (__builtin_expect (key < PTHREAD_KEY_2NDLEVEL_SIZE, 1)) |
| 33 | data = &THREAD_SELF->specific_1stblock[key]; |
| 34 | else |
| 35 | { |
| 36 | /* Verify the key is sane. */ |
| 37 | if (key >= PTHREAD_KEYS_MAX) |
| 38 | /* Not valid. */ |
| 39 | return NULL; |
| 40 | |
| 41 | unsigned int idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; |
| 42 | unsigned int idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; |
| 43 | |
| 44 | /* If the sequence number doesn't match or the key cannot be defined |
| 45 | for this thread since the second level array is not allocated |
| 46 | return NULL, too. */ |
| 47 | struct pthread_key_data *level2 = THREAD_GETMEM_NC (THREAD_SELF, |
| 48 | specific, idx1st); |
| 49 | if (level2 == NULL) |
| 50 | /* Not allocated, therefore no data. */ |
| 51 | return NULL; |
| 52 | |
| 53 | /* There is data. */ |
| 54 | data = &level2[idx2nd]; |
| 55 | } |
| 56 | |
| 57 | void *result = data->data; |
| 58 | if (result != NULL) |
| 59 | { |
| 60 | uintptr_t seq = data->seq; |
| 61 | |
| 62 | if (__builtin_expect (seq != __pthread_keys[key].seq, 0)) |
| 63 | result = data->data = NULL; |
| 64 | } |
| 65 | |
| 66 | return result; |
| 67 | } |
| 68 | strong_alias (__pthread_getspecific, pthread_getspecific) |
| 69 | strong_alias (__pthread_getspecific, __pthread_getspecific_internal) |