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 1.1 2005/02/01 12:38:27 davidxu Exp $ 34 */ 35 #include <signal.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <errno.h> 39 #include <pthread.h> 40 #include "thr_private.h" 41 42 /* Static variables: */ 43 struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; 44 45 __weak_reference(_pthread_key_create, pthread_key_create); 46 __weak_reference(_pthread_key_delete, pthread_key_delete); 47 __weak_reference(_pthread_getspecific, pthread_getspecific); 48 __weak_reference(_pthread_setspecific, pthread_setspecific); 49 50 51 int 52 _pthread_key_create(pthread_key_t *key, void (*destructor) (void *)) 53 { 54 struct pthread *curthread = _get_curthread(); 55 int i; 56 57 /* Lock the key table: */ 58 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 59 for (i = 0; i < PTHREAD_KEYS_MAX; i++) { 60 61 if (_thread_keytable[i].allocated == 0) { 62 _thread_keytable[i].allocated = 1; 63 _thread_keytable[i].destructor = destructor; 64 _thread_keytable[i].seqno++; 65 66 /* Unlock the key table: */ 67 THR_LOCK_RELEASE(curthread, &_keytable_lock); 68 *key = i; 69 return (0); 70 } 71 72 } 73 /* Unlock the key table: */ 74 THR_LOCK_RELEASE(curthread, &_keytable_lock); 75 return (EAGAIN); 76 } 77 78 int 79 _pthread_key_delete(pthread_key_t key) 80 { 81 struct pthread *curthread = _get_curthread(); 82 int ret = 0; 83 84 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 85 /* Lock the key table: */ 86 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 87 88 if (_thread_keytable[key].allocated) 89 _thread_keytable[key].allocated = 0; 90 else 91 ret = EINVAL; 92 93 /* Unlock the key table: */ 94 THR_LOCK_RELEASE(curthread, &_keytable_lock); 95 } else 96 ret = EINVAL; 97 return (ret); 98 } 99 100 void 101 _thread_cleanupspecific(void) 102 { 103 struct pthread *curthread = _get_curthread(); 104 void (*destructor)( void *); 105 void *data = NULL; 106 int key; 107 int i; 108 109 if (curthread->specific == NULL) 110 return; 111 112 /* Lock the key table: */ 113 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 114 for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) && 115 (curthread->specific_data_count > 0); i++) { 116 for (key = 0; (key < PTHREAD_KEYS_MAX) && 117 (curthread->specific_data_count > 0); key++) { 118 destructor = NULL; 119 120 if (_thread_keytable[key].allocated && 121 (curthread->specific[key].data != NULL)) { 122 if (curthread->specific[key].seqno == 123 _thread_keytable[key].seqno) { 124 data = (void *) 125 curthread->specific[key].data; 126 destructor = _thread_keytable[key].destructor; 127 } 128 curthread->specific[key].data = NULL; 129 curthread->specific_data_count--; 130 } 131 132 /* 133 * If there is a destructore, call it 134 * with the key table entry unlocked: 135 */ 136 if (destructor != NULL) { 137 /* 138 * Don't hold the lock while calling the 139 * destructor: 140 */ 141 THR_LOCK_RELEASE(curthread, &_keytable_lock); 142 destructor(data); 143 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 144 } 145 } 146 } 147 THR_LOCK_RELEASE(curthread, &_keytable_lock); 148 free(curthread->specific); 149 curthread->specific = NULL; 150 if (curthread->specific_data_count > 0) 151 stderr_debug("Thread %p has exited with leftover " 152 "thread-specific data after %d destructor iterations\n", 153 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 154 } 155 156 static inline struct pthread_specific_elem * 157 pthread_key_allocate_data(void) 158 { 159 struct pthread_specific_elem *new_data; 160 161 new_data = (struct pthread_specific_elem *) 162 malloc(sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 163 if (new_data != NULL) { 164 memset((void *) new_data, 0, 165 sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 166 } 167 return (new_data); 168 } 169 170 int 171 _pthread_setspecific(pthread_key_t key, const void *value) 172 { 173 struct pthread *pthread; 174 int ret = 0; 175 176 /* Point to the running thread: */ 177 pthread = _get_curthread(); 178 179 if ((pthread->specific) || 180 (pthread->specific = pthread_key_allocate_data())) { 181 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 182 if (_thread_keytable[key].allocated) { 183 if (pthread->specific[key].data == NULL) { 184 if (value != NULL) 185 pthread->specific_data_count++; 186 } else if (value == NULL) 187 pthread->specific_data_count--; 188 pthread->specific[key].data = value; 189 pthread->specific[key].seqno = 190 _thread_keytable[key].seqno; 191 ret = 0; 192 } else 193 ret = EINVAL; 194 } else 195 ret = EINVAL; 196 } else 197 ret = ENOMEM; 198 return (ret); 199 } 200 201 void * 202 _pthread_getspecific(pthread_key_t key) 203 { 204 struct pthread *pthread; 205 void *data; 206 207 /* Point to the running thread: */ 208 pthread = _get_curthread(); 209 210 /* Check if there is specific data: */ 211 if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) { 212 /* Check if this key has been used before: */ 213 if (_thread_keytable[key].allocated && 214 (pthread->specific[key].seqno == _thread_keytable[key].seqno)) { 215 /* Return the value: */ 216 data = (void *) pthread->specific[key].data; 217 } else { 218 /* 219 * This key has not been used before, so return NULL 220 * instead: 221 */ 222 data = NULL; 223 } 224 } else 225 /* No specific data has been created, so just return NULL: */ 226 data = NULL; 227 return (data); 228 } 229