1 /* 2 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by John Birrell. 16 * 4. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD: src/lib/libpthread/thread/thr_spec.c,v 1.22 2004/07/13 22:49:58 davidxu Exp $ 33 * $DragonFly: src/lib/libthread_xu/thread/thr_spec.c,v 1.2 2005/03/29 19:26:20 joerg Exp $ 34 */ 35 36 #include <machine/tls.h> 37 38 #include <signal.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <errno.h> 42 #include <pthread.h> 43 #include "thr_private.h" 44 45 /* Static variables: */ 46 struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; 47 48 __weak_reference(_pthread_key_create, pthread_key_create); 49 __weak_reference(_pthread_key_delete, pthread_key_delete); 50 __weak_reference(_pthread_getspecific, pthread_getspecific); 51 __weak_reference(_pthread_setspecific, pthread_setspecific); 52 53 54 int 55 _pthread_key_create(pthread_key_t *key, void (*destructor) (void *)) 56 { 57 struct pthread *curthread = tls_get_curthread(); 58 int i; 59 60 /* Lock the key table: */ 61 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 62 for (i = 0; i < PTHREAD_KEYS_MAX; i++) { 63 64 if (_thread_keytable[i].allocated == 0) { 65 _thread_keytable[i].allocated = 1; 66 _thread_keytable[i].destructor = destructor; 67 _thread_keytable[i].seqno++; 68 69 /* Unlock the key table: */ 70 THR_LOCK_RELEASE(curthread, &_keytable_lock); 71 *key = i; 72 return (0); 73 } 74 75 } 76 /* Unlock the key table: */ 77 THR_LOCK_RELEASE(curthread, &_keytable_lock); 78 return (EAGAIN); 79 } 80 81 int 82 _pthread_key_delete(pthread_key_t key) 83 { 84 struct pthread *curthread = tls_get_curthread(); 85 int ret = 0; 86 87 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 88 /* Lock the key table: */ 89 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 90 91 if (_thread_keytable[key].allocated) 92 _thread_keytable[key].allocated = 0; 93 else 94 ret = EINVAL; 95 96 /* Unlock the key table: */ 97 THR_LOCK_RELEASE(curthread, &_keytable_lock); 98 } else 99 ret = EINVAL; 100 return (ret); 101 } 102 103 void 104 _thread_cleanupspecific(void) 105 { 106 struct pthread *curthread = tls_get_curthread(); 107 void (*destructor)( void *); 108 void *data = NULL; 109 int key; 110 int i; 111 112 if (curthread->specific == NULL) 113 return; 114 115 /* Lock the key table: */ 116 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 117 for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) && 118 (curthread->specific_data_count > 0); i++) { 119 for (key = 0; (key < PTHREAD_KEYS_MAX) && 120 (curthread->specific_data_count > 0); key++) { 121 destructor = NULL; 122 123 if (_thread_keytable[key].allocated && 124 (curthread->specific[key].data != NULL)) { 125 if (curthread->specific[key].seqno == 126 _thread_keytable[key].seqno) { 127 data = (void *) 128 curthread->specific[key].data; 129 destructor = _thread_keytable[key].destructor; 130 } 131 curthread->specific[key].data = NULL; 132 curthread->specific_data_count--; 133 } 134 135 /* 136 * If there is a destructore, call it 137 * with the key table entry unlocked: 138 */ 139 if (destructor != NULL) { 140 /* 141 * Don't hold the lock while calling the 142 * destructor: 143 */ 144 THR_LOCK_RELEASE(curthread, &_keytable_lock); 145 destructor(data); 146 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 147 } 148 } 149 } 150 THR_LOCK_RELEASE(curthread, &_keytable_lock); 151 free(curthread->specific); 152 curthread->specific = NULL; 153 if (curthread->specific_data_count > 0) 154 stderr_debug("Thread %p has exited with leftover " 155 "thread-specific data after %d destructor iterations\n", 156 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 157 } 158 159 static inline struct pthread_specific_elem * 160 pthread_key_allocate_data(void) 161 { 162 struct pthread_specific_elem *new_data; 163 164 new_data = (struct pthread_specific_elem *) 165 malloc(sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 166 if (new_data != NULL) { 167 memset((void *) new_data, 0, 168 sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 169 } 170 return (new_data); 171 } 172 173 int 174 _pthread_setspecific(pthread_key_t key, const void *value) 175 { 176 struct pthread *pthread; 177 int ret = 0; 178 179 /* Point to the running thread: */ 180 pthread = tls_get_curthread(); 181 182 if ((pthread->specific) || 183 (pthread->specific = pthread_key_allocate_data())) { 184 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 185 if (_thread_keytable[key].allocated) { 186 if (pthread->specific[key].data == NULL) { 187 if (value != NULL) 188 pthread->specific_data_count++; 189 } else if (value == NULL) 190 pthread->specific_data_count--; 191 pthread->specific[key].data = value; 192 pthread->specific[key].seqno = 193 _thread_keytable[key].seqno; 194 ret = 0; 195 } else 196 ret = EINVAL; 197 } else 198 ret = EINVAL; 199 } else 200 ret = ENOMEM; 201 return (ret); 202 } 203 204 void * 205 _pthread_getspecific(pthread_key_t key) 206 { 207 struct pthread *pthread; 208 void *data; 209 210 /* Point to the running thread: */ 211 pthread = tls_get_curthread(); 212 213 /* Check if there is specific data: */ 214 if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) { 215 /* Check if this key has been used before: */ 216 if (_thread_keytable[key].allocated && 217 (pthread->specific[key].seqno == _thread_keytable[key].seqno)) { 218 /* Return the value: */ 219 data = (void *) pthread->specific[key].data; 220 } else { 221 /* 222 * This key has not been used before, so return NULL 223 * instead: 224 */ 225 data = NULL; 226 } 227 } else 228 /* No specific data has been created, so just return NULL: */ 229 data = NULL; 230 return (data); 231 } 232