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, see
17 <http://www.gnu.org/licenses/>. */
18
19 #include <stdlib.h>
20 #include "pthreadP.h"
21
22
23 attribute_protected
24 void *
__pthread_getspecific(pthread_key_t key)25 __pthread_getspecific (pthread_key_t key)
26 {
27 struct pthread_key_data *data;
28
29 /* Special case access to the first 2nd-level block. This is the
30 usual case. */
31 if (__builtin_expect (key < PTHREAD_KEY_2NDLEVEL_SIZE, 1))
32 data = &THREAD_SELF->specific_1stblock[key];
33 else
34 {
35 /* Verify the key is sane. */
36 if (key >= PTHREAD_KEYS_MAX)
37 /* Not valid. */
38 return NULL;
39
40 unsigned int idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE;
41 unsigned int idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE;
42
43 /* If the sequence number doesn't match or the key cannot be defined
44 for this thread since the second level array is not allocated
45 return NULL, too. */
46 struct pthread_key_data *level2 = THREAD_GETMEM_NC (THREAD_SELF,
47 specific, idx1st);
48 if (level2 == NULL)
49 /* Not allocated, therefore no data. */
50 return NULL;
51
52 /* There is data. */
53 data = &level2[idx2nd];
54 }
55
56 void *result = data->data;
57 if (result != NULL)
58 {
59 uintptr_t seq = data->seq;
60
61 if (__builtin_expect (seq != __pthread_keys[key].seq, 0))
62 result = data->data = NULL;
63 }
64
65 return result;
66 }
67 strong_alias (__pthread_getspecific, pthread_getspecific)
68 strong_alias (__pthread_getspecific, __pthread_getspecific_internal)
69