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 * $FreeBSD$ 30 */ 31 32 #include "namespace.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 #include "libc_private.h" 40 41 #include "thr_private.h" 42 43 /* Static variables: */ 44 struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; 45 46 __weak_reference(_pthread_key_create, pthread_key_create); 47 __weak_reference(_pthread_key_delete, pthread_key_delete); 48 __weak_reference(_pthread_getspecific, pthread_getspecific); 49 __weak_reference(_pthread_setspecific, pthread_setspecific); 50 51 52 int 53 _pthread_key_create(pthread_key_t *key, void (*destructor) (void *)) 54 { 55 struct pthread *curthread; 56 int i; 57 58 _thr_check_init(); 59 60 curthread = _get_curthread(); 61 62 /* Lock the key table: */ 63 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 64 for (i = 0; i < PTHREAD_KEYS_MAX; i++) { 65 66 if (_thread_keytable[i].allocated == 0) { 67 _thread_keytable[i].allocated = 1; 68 _thread_keytable[i].destructor = destructor; 69 _thread_keytable[i].seqno++; 70 71 /* Unlock the key table: */ 72 THR_LOCK_RELEASE(curthread, &_keytable_lock); 73 *key = i; 74 return (0); 75 } 76 77 } 78 /* Unlock the key table: */ 79 THR_LOCK_RELEASE(curthread, &_keytable_lock); 80 return (EAGAIN); 81 } 82 83 int 84 _pthread_key_delete(pthread_key_t key) 85 { 86 struct pthread *curthread = _get_curthread(); 87 int ret = 0; 88 89 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 90 /* Lock the key table: */ 91 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 92 93 if (_thread_keytable[key].allocated) 94 _thread_keytable[key].allocated = 0; 95 else 96 ret = EINVAL; 97 98 /* Unlock the key table: */ 99 THR_LOCK_RELEASE(curthread, &_keytable_lock); 100 } else 101 ret = EINVAL; 102 return (ret); 103 } 104 105 void 106 _thread_cleanupspecific(void) 107 { 108 struct pthread *curthread = _get_curthread(); 109 void (*destructor)( void *); 110 const void *data = NULL; 111 int key; 112 int i; 113 114 if (curthread->specific == NULL) 115 return; 116 117 /* Lock the key table: */ 118 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 119 for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) && 120 (curthread->specific_data_count > 0); i++) { 121 for (key = 0; (key < PTHREAD_KEYS_MAX) && 122 (curthread->specific_data_count > 0); key++) { 123 destructor = NULL; 124 125 if (_thread_keytable[key].allocated && 126 (curthread->specific[key].data != NULL)) { 127 if (curthread->specific[key].seqno == 128 _thread_keytable[key].seqno) { 129 data = curthread->specific[key].data; 130 destructor = _thread_keytable[key].destructor; 131 } 132 curthread->specific[key].data = NULL; 133 curthread->specific_data_count--; 134 } 135 else if (curthread->specific[key].data != NULL) { 136 /* 137 * This can happen if the key is deleted via 138 * pthread_key_delete without first setting the value 139 * to NULL in all threads. POSIX says that the 140 * destructor is not invoked in this case. 141 */ 142 curthread->specific[key].data = NULL; 143 curthread->specific_data_count--; 144 } 145 146 /* 147 * If there is a destructor, call it 148 * with the key table entry unlocked: 149 */ 150 if (destructor != NULL) { 151 /* 152 * Don't hold the lock while calling the 153 * destructor: 154 */ 155 THR_LOCK_RELEASE(curthread, &_keytable_lock); 156 destructor(__DECONST(void *, data)); 157 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 158 } 159 } 160 } 161 THR_LOCK_RELEASE(curthread, &_keytable_lock); 162 free(curthread->specific); 163 curthread->specific = NULL; 164 if (curthread->specific_data_count > 0) 165 stderr_debug("Thread %p has exited with leftover " 166 "thread-specific data after %d destructor iterations\n", 167 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 168 } 169 170 static inline struct pthread_specific_elem * 171 pthread_key_allocate_data(void) 172 { 173 struct pthread_specific_elem *new_data; 174 175 new_data = (struct pthread_specific_elem *) 176 calloc(1, sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 177 return (new_data); 178 } 179 180 int 181 _pthread_setspecific(pthread_key_t key, const void *value) 182 { 183 struct pthread *pthread; 184 int ret = 0; 185 186 /* Point to the running thread: */ 187 pthread = _get_curthread(); 188 189 if ((pthread->specific) || 190 (pthread->specific = pthread_key_allocate_data())) { 191 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 192 if (_thread_keytable[key].allocated) { 193 if (pthread->specific[key].data == NULL) { 194 if (value != NULL) 195 pthread->specific_data_count++; 196 } else if (value == NULL) 197 pthread->specific_data_count--; 198 pthread->specific[key].data = value; 199 pthread->specific[key].seqno = 200 _thread_keytable[key].seqno; 201 ret = 0; 202 } else 203 ret = EINVAL; 204 } else 205 ret = EINVAL; 206 } else 207 ret = ENOMEM; 208 return (ret); 209 } 210 211 void * 212 _pthread_getspecific(pthread_key_t key) 213 { 214 struct pthread *pthread; 215 const void *data; 216 217 /* Point to the running thread: */ 218 pthread = _get_curthread(); 219 220 /* Check if there is specific data: */ 221 if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) { 222 /* Check if this key has been used before: */ 223 if (_thread_keytable[key].allocated && 224 (pthread->specific[key].seqno == _thread_keytable[key].seqno)) { 225 /* Return the value: */ 226 data = pthread->specific[key].data; 227 } else { 228 /* 229 * This key has not been used before, so return NULL 230 * instead: 231 */ 232 data = NULL; 233 } 234 } else 235 /* No specific data has been created, so just return NULL: */ 236 data = NULL; 237 return (__DECONST(void *, data)); 238 } 239 240 void 241 _thr_tsd_unload(struct dl_phdr_info *phdr_info) 242 { 243 struct pthread *curthread = _get_curthread(); 244 void (*destructor)(void *); 245 int key; 246 247 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 248 for (key = 0; key < PTHREAD_KEYS_MAX; key++) { 249 if (_thread_keytable[key].allocated) { 250 destructor = _thread_keytable[key].destructor; 251 if (destructor != NULL) { 252 if (__elf_phdr_match_addr(phdr_info, destructor)) 253 _thread_keytable[key].destructor = NULL; 254 } 255 } 256 } 257 THR_LOCK_RELEASE(curthread, &_keytable_lock); 258 } 259