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. Neither the name of the author nor the names of any co-contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 */ 30 31 #include "namespace.h" 32 #include <machine/tls.h> 33 #include <signal.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <errno.h> 37 #include <pthread.h> 38 #include "un-namespace.h" 39 40 #include "thr_private.h" 41 42 struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; 43 umtx_t _keytable_lock; 44 45 int 46 _pthread_key_create(pthread_key_t *key, void (*destructor) (void *)) 47 { 48 struct pthread *curthread; 49 int i; 50 51 /* User program might be preparing to call pthread_create() */ 52 _thr_check_init(); 53 54 curthread = tls_get_curthread(); 55 56 /* Lock the key table: */ 57 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 58 for (i = 0; i < PTHREAD_KEYS_MAX; i++) { 59 60 if (_thread_keytable[i].allocated == 0) { 61 _thread_keytable[i].allocated = 1; 62 _thread_keytable[i].destructor = destructor; 63 _thread_keytable[i].seqno++; 64 65 /* Unlock the key table: */ 66 THR_LOCK_RELEASE(curthread, &_keytable_lock); 67 *key = i; 68 return (0); 69 } 70 71 } 72 /* Unlock the key table: */ 73 THR_LOCK_RELEASE(curthread, &_keytable_lock); 74 return (EAGAIN); 75 } 76 77 int 78 _pthread_key_delete(pthread_key_t key) 79 { 80 struct pthread *curthread = tls_get_curthread(); 81 int ret = 0; 82 83 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 84 /* Lock the key table: */ 85 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 86 87 if (_thread_keytable[key].allocated) 88 _thread_keytable[key].allocated = 0; 89 else 90 ret = EINVAL; 91 92 /* Unlock the key table: */ 93 THR_LOCK_RELEASE(curthread, &_keytable_lock); 94 } else 95 ret = EINVAL; 96 return (ret); 97 } 98 99 void 100 _thread_cleanupspecific(void) 101 { 102 struct pthread *curthread = tls_get_curthread(); 103 void (*destructor)( void *); 104 const void *data = NULL; 105 int key; 106 int i; 107 108 if (curthread->specific == NULL) 109 return; 110 111 /* Lock the key table: */ 112 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 113 for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) && 114 (curthread->specific_data_count > 0); i++) { 115 for (key = 0; (key < PTHREAD_KEYS_MAX) && 116 (curthread->specific_data_count > 0); key++) { 117 destructor = NULL; 118 119 if (_thread_keytable[key].allocated && 120 (curthread->specific[key].data != NULL)) { 121 if (curthread->specific[key].seqno == 122 _thread_keytable[key].seqno) { 123 data = curthread->specific[key].data; 124 destructor = _thread_keytable[key].destructor; 125 } 126 curthread->specific[key].data = NULL; 127 curthread->specific_data_count--; 128 } else if (curthread->specific[key].data != NULL) { 129 /* 130 * This can happen if the key is deleted via 131 * pthread_key_delete without first setting the value 132 * to NULL in all threads. POSIX says that the 133 * destructor is not invoked in this case. 134 */ 135 curthread->specific[key].data = NULL; 136 curthread->specific_data_count--; 137 } 138 139 /* 140 * If there is a destructor, call it 141 * with the key table entry unlocked: 142 */ 143 if (destructor != NULL) { 144 /* 145 * Don't hold the lock while calling the 146 * destructor: 147 */ 148 THR_LOCK_RELEASE(curthread, &_keytable_lock); 149 destructor(__DECONST(void *, data)); 150 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 151 } 152 } 153 } 154 THR_LOCK_RELEASE(curthread, &_keytable_lock); 155 free(curthread->specific); 156 curthread->specific = NULL; 157 if (curthread->specific_data_count > 0) 158 stderr_debug("Thread %p has exited with leftover " 159 "thread-specific data after %d destructor iterations\n", 160 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 161 } 162 163 static inline struct pthread_specific_elem * 164 pthread_key_allocate_data(void) 165 { 166 struct pthread_specific_elem *new_data; 167 168 new_data = (struct pthread_specific_elem *) 169 malloc(sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 170 if (new_data != NULL) { 171 memset((void *) new_data, 0, 172 sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 173 } 174 return (new_data); 175 } 176 177 int 178 _pthread_setspecific(pthread_key_t key, const void *value) 179 { 180 struct pthread *pthread; 181 int ret = 0; 182 183 /* Point to the running thread: */ 184 pthread = tls_get_curthread(); 185 186 if ((pthread->specific) || 187 (pthread->specific = pthread_key_allocate_data())) { 188 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 189 if (_thread_keytable[key].allocated) { 190 if (pthread->specific[key].data == NULL) { 191 if (value != NULL) 192 pthread->specific_data_count++; 193 } else if (value == NULL) 194 pthread->specific_data_count--; 195 pthread->specific[key].data = value; 196 pthread->specific[key].seqno = 197 _thread_keytable[key].seqno; 198 ret = 0; 199 } else 200 ret = EINVAL; 201 } else 202 ret = EINVAL; 203 } else 204 ret = ENOMEM; 205 return (ret); 206 } 207 208 void * 209 _pthread_getspecific(pthread_key_t key) 210 { 211 struct pthread *pthread; 212 const void *data; 213 214 /* Point to the running thread: */ 215 pthread = tls_get_curthread(); 216 217 /* Check if there is specific data: */ 218 if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) { 219 /* Check if this key has been used before: */ 220 if (_thread_keytable[key].allocated && 221 (pthread->specific[key].seqno == _thread_keytable[key].seqno)) { 222 /* Return the value: */ 223 data = pthread->specific[key].data; 224 } else { 225 /* 226 * This key has not been used before, so return NULL 227 * instead. 228 */ 229 data = NULL; 230 } 231 } else 232 /* No specific data has been created, so just return NULL: */ 233 data = NULL; 234 return __DECONST(void *, data); 235 } 236 237 __strong_reference(_pthread_key_create, pthread_key_create); 238 __strong_reference(_pthread_key_delete, pthread_key_delete); 239 __strong_reference(_pthread_getspecific, pthread_getspecific); 240 __strong_reference(_pthread_setspecific, pthread_setspecific); 241