1/* Copyright (C) 2002-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <stdlib.h>
20#include "pthreadP.h"
21#include <shlib-compat.h>
22
23int
24___pthread_setspecific (pthread_key_t key, const void *value)
25{
26 struct pthread *self;
27 unsigned int idx1st;
28 unsigned int idx2nd;
29 struct pthread_key_data *level2;
30 unsigned int seq;
31
32 self = THREAD_SELF;
33
34 /* Special case access to the first 2nd-level block. This is the
35 usual case. */
36 if (__glibc_likely (key < PTHREAD_KEY_2NDLEVEL_SIZE))
37 {
38 /* Verify the key is sane. */
39 if (KEY_UNUSED ((seq = __pthread_keys[key].seq)))
40 /* Not valid. */
41 return EINVAL;
42
43 level2 = &self->specific_1stblock[key];
44
45 /* Remember that we stored at least one set of data. */
46 if (value != NULL)
47 THREAD_SETMEM (self, specific_used, true);
48 }
49 else
50 {
51 if (key >= PTHREAD_KEYS_MAX
52 || KEY_UNUSED ((seq = __pthread_keys[key].seq)))
53 /* Not valid. */
54 return EINVAL;
55
56 idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE;
57 idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE;
58
59 /* This is the second level array. Allocate it if necessary. */
60 level2 = THREAD_GETMEM_NC (self, specific, idx1st);
61 if (level2 == NULL)
62 {
63 if (value == NULL)
64 /* We don't have to do anything. The value would in any case
65 be NULL. We can save the memory allocation. */
66 return 0;
67
68 level2
69 = (struct pthread_key_data *) calloc (PTHREAD_KEY_2NDLEVEL_SIZE,
70 size: sizeof (*level2));
71 if (level2 == NULL)
72 return ENOMEM;
73
74 THREAD_SETMEM_NC (self, specific, idx1st, level2);
75 }
76
77 /* Pointer to the right array element. */
78 level2 = &level2[idx2nd];
79
80 /* Remember that we stored at least one set of data. */
81 THREAD_SETMEM (self, specific_used, true);
82 }
83
84 /* Store the data and the sequence number so that we can recognize
85 stale data. */
86 level2->seq = seq;
87 level2->data = (void *) value;
88
89 return 0;
90}
91versioned_symbol (libc, ___pthread_setspecific, pthread_setspecific,
92 GLIBC_2_34);
93libc_hidden_ver (___pthread_setspecific, __pthread_setspecific)
94#ifndef SHARED
95strong_alias (___pthread_setspecific, __pthread_setspecific)
96#endif
97
98#if OTHER_SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_34)
99compat_symbol (libpthread, ___pthread_setspecific, __pthread_setspecific,
100 GLIBC_2_0);
101compat_symbol (libpthread, ___pthread_setspecific, pthread_setspecific,
102 GLIBC_2_0);
103#endif
104

source code of glibc/nptl/pthread_setspecific.c