blob: 8e08aa4d08c48e846a8ab7656dea2d335bdc092e [file] [log] [blame]
lh9ed821d2023-04-07 01:36:19 -07001/* Linuxthreads - a simple clone()-based implementation of Posix */
2/* threads for Linux. */
3/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
4/* */
5/* This program is free software; you can redistribute it and/or */
6/* modify it under the terms of the GNU Library General Public License */
7/* as published by the Free Software Foundation; either version 2 */
8/* of the License, or (at your option) any later version. */
9/* */
10/* This program 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 */
13/* GNU Library General Public License for more details. */
14
15/* Thread-specific data */
16
17#include <features.h>
18#include <errno.h>
19#include <stddef.h>
20#include <stdlib.h>
21#include "pthread.h"
22#include "internals.h"
23#include "spinlock.h"
24#include "restart.h"
25
26/* Table of keys. */
27
28static struct pthread_key_struct pthread_keys[PTHREAD_KEYS_MAX] =
29 { { 0, NULL } };
30
31/* For debugging purposes put the maximum number of keys in a variable. */
32const int __linuxthreads_pthread_keys_max = PTHREAD_KEYS_MAX;
33const int __linuxthreads_pthread_key_2ndlevel_size = PTHREAD_KEY_2NDLEVEL_SIZE;
34
35/* Mutex to protect access to pthread_keys */
36
37static pthread_mutex_t pthread_keys_mutex = PTHREAD_MUTEX_INITIALIZER;
38
39/* Create a new key */
40
41int pthread_key_create(pthread_key_t * key, destr_function destr)
42{
43 int i;
44
45 __pthread_mutex_lock(&pthread_keys_mutex);
46 for (i = 0; i < PTHREAD_KEYS_MAX; i++) {
47 if (! pthread_keys[i].in_use) {
48 /* Mark key in use */
49 pthread_keys[i].in_use = 1;
50 pthread_keys[i].destr = destr;
51 __pthread_mutex_unlock(&pthread_keys_mutex);
52 *key = i;
53 return 0;
54 }
55 }
56 __pthread_mutex_unlock(&pthread_keys_mutex);
57 return EAGAIN;
58}
59
60/* Delete a key */
61int pthread_key_delete(pthread_key_t key)
62{
63 pthread_descr self = thread_self();
64
65 __pthread_mutex_lock(&pthread_keys_mutex);
66 if (key >= PTHREAD_KEYS_MAX || !pthread_keys[key].in_use) {
67 __pthread_mutex_unlock(&pthread_keys_mutex);
68 return EINVAL;
69 }
70 pthread_keys[key].in_use = 0;
71 pthread_keys[key].destr = NULL;
72
73 /* Set the value of the key to NULL in all running threads, so
74 that if the key is reallocated later by pthread_key_create, its
75 associated values will be NULL in all threads.
76 Do nothing if no threads have been created yet. */
77 if (__pthread_manager_request != -1)
78 {
79 pthread_descr th;
80 unsigned int idx1st, idx2nd;
81
82 idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE;
83 idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE;
84 th = self;
85 do {
86 /* If the thread already is terminated don't modify the memory. */
87 if (!th->p_terminated && th->p_specific[idx1st] != NULL)
88 th->p_specific[idx1st][idx2nd] = NULL;
89 th = th->p_nextlive;
90 } while (th != self);
91 }
92
93 __pthread_mutex_unlock(&pthread_keys_mutex);
94 return 0;
95}
96
97/* Set the value of a key */
98
99int pthread_setspecific(pthread_key_t key, const void * pointer)
100{
101 pthread_descr self = thread_self();
102 unsigned int idx1st, idx2nd;
103
104 if (key >= PTHREAD_KEYS_MAX || !pthread_keys[key].in_use)
105 return EINVAL;
106 idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE;
107 idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE;
108 if (THREAD_GETMEM_NC(self, p_specific[idx1st]) == NULL) {
109 void *newp = calloc(PTHREAD_KEY_2NDLEVEL_SIZE, sizeof (void *));
110 if (newp == NULL)
111 return ENOMEM;
112 THREAD_SETMEM_NC(self, p_specific[idx1st], newp);
113 }
114 THREAD_GETMEM_NC(self, p_specific[idx1st])[idx2nd] = (void *) pointer;
115 return 0;
116}
117
118/* Get the value of a key */
119
120void * pthread_getspecific(pthread_key_t key)
121{
122 pthread_descr self = thread_self();
123 unsigned int idx1st, idx2nd;
124
125 if (key >= PTHREAD_KEYS_MAX)
126 return NULL;
127 idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE;
128 idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE;
129 if (THREAD_GETMEM_NC(self, p_specific[idx1st]) == NULL
130 || !pthread_keys[key].in_use)
131 return NULL;
132 return THREAD_GETMEM_NC(self, p_specific[idx1st])[idx2nd];
133}
134
135/* Call the destruction routines on all keys */
136
137void __pthread_destroy_specifics(void)
138{
139 pthread_descr self = thread_self();
140 int i, j, round, found_nonzero;
141 destr_function destr;
142 void * data;
143
144 for (round = 0, found_nonzero = 1;
145 found_nonzero && round < PTHREAD_DESTRUCTOR_ITERATIONS;
146 round++) {
147 found_nonzero = 0;
148 for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++)
149 if (THREAD_GETMEM_NC(self, p_specific[i]) != NULL)
150 for (j = 0; j < PTHREAD_KEY_2NDLEVEL_SIZE; j++) {
151 destr = pthread_keys[i * PTHREAD_KEY_2NDLEVEL_SIZE + j].destr;
152 data = THREAD_GETMEM_NC(self, p_specific[i])[j];
153 if (destr != NULL && data != NULL) {
154 THREAD_GETMEM_NC(self, p_specific[i])[j] = NULL;
155 destr(data);
156 found_nonzero = 1;
157 }
158 }
159 }
160 __pthread_lock(THREAD_GETMEM(self, p_lock), self);
161 for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) {
162 if (THREAD_GETMEM_NC(self, p_specific[i]) != NULL) {
163 free(THREAD_GETMEM_NC(self, p_specific[i]));
164 THREAD_SETMEM_NC(self, p_specific[i], NULL);
165 }
166 }
167 __pthread_unlock(THREAD_GETMEM(self, p_lock));
168}
169
170#ifndef USE___THREAD
171
172/* Thread-specific data for libc. */
173
174int
175__pthread_internal_tsd_set (int key, const void * pointer)
176{
177 pthread_descr self = thread_self();
178
179 THREAD_SETMEM_NC(self, p_libc_specific[key], (void *) pointer);
180 return 0;
181}
182
183void *
184__pthread_internal_tsd_get (int key)
185{
186 pthread_descr self = thread_self();
187
188 return THREAD_GETMEM_NC(self, p_libc_specific[key]);
189}
190
191void ** __attribute__ ((__const__))
192__pthread_internal_tsd_address (int key)
193{
194 pthread_descr self = thread_self();
195 return &self->p_libc_specific[key];
196}
197
198#endif