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 + 1; 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 userkey) 85 { 86 struct pthread *curthread = _get_curthread(); 87 int key = userkey - 1; 88 int ret = 0; 89 90 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 91 /* Lock the key table: */ 92 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 93 94 if (_thread_keytable[key].allocated) 95 _thread_keytable[key].allocated = 0; 96 else 97 ret = EINVAL; 98 99 /* Unlock the key table: */ 100 THR_LOCK_RELEASE(curthread, &_keytable_lock); 101 } else 102 ret = EINVAL; 103 return (ret); 104 } 105 106 void 107 _thread_cleanupspecific(void) 108 { 109 struct pthread *curthread = _get_curthread(); 110 void (*destructor)( void *); 111 const void *data = NULL; 112 int key; 113 int i; 114 115 if (curthread->specific == NULL) 116 return; 117 118 /* Lock the key table: */ 119 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 120 for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) && 121 (curthread->specific_data_count > 0); i++) { 122 for (key = 0; (key < PTHREAD_KEYS_MAX) && 123 (curthread->specific_data_count > 0); key++) { 124 destructor = NULL; 125 126 if (_thread_keytable[key].allocated && 127 (curthread->specific[key].data != NULL)) { 128 if (curthread->specific[key].seqno == 129 _thread_keytable[key].seqno) { 130 data = curthread->specific[key].data; 131 destructor = _thread_keytable[key].destructor; 132 } 133 curthread->specific[key].data = NULL; 134 curthread->specific_data_count--; 135 } 136 else if (curthread->specific[key].data != NULL) { 137 /* 138 * This can happen if the key is deleted via 139 * pthread_key_delete without first setting the value 140 * to NULL in all threads. POSIX says that the 141 * destructor is not invoked in this case. 142 */ 143 curthread->specific[key].data = NULL; 144 curthread->specific_data_count--; 145 } 146 147 /* 148 * If there is a destructor, call it 149 * with the key table entry unlocked: 150 */ 151 if (destructor != NULL) { 152 /* 153 * Don't hold the lock while calling the 154 * destructor: 155 */ 156 THR_LOCK_RELEASE(curthread, &_keytable_lock); 157 destructor(__DECONST(void *, data)); 158 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 159 } 160 } 161 } 162 THR_LOCK_RELEASE(curthread, &_keytable_lock); 163 free(curthread->specific); 164 curthread->specific = NULL; 165 if (curthread->specific_data_count > 0) 166 stderr_debug("Thread %p has exited with leftover " 167 "thread-specific data after %d destructor iterations\n", 168 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 169 } 170 171 static inline struct pthread_specific_elem * 172 pthread_key_allocate_data(void) 173 { 174 struct pthread_specific_elem *new_data; 175 176 new_data = (struct pthread_specific_elem *) 177 calloc(1, sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 178 return (new_data); 179 } 180 181 int 182 _pthread_setspecific(pthread_key_t userkey, const void *value) 183 { 184 struct pthread *pthread; 185 pthread_key_t key = userkey - 1; 186 int ret = 0; 187 188 /* Point to the running thread: */ 189 pthread = _get_curthread(); 190 191 if ((pthread->specific) || 192 (pthread->specific = pthread_key_allocate_data())) { 193 if ((unsigned int)key < PTHREAD_KEYS_MAX) { 194 if (_thread_keytable[key].allocated) { 195 if (pthread->specific[key].data == NULL) { 196 if (value != NULL) 197 pthread->specific_data_count++; 198 } else if (value == NULL) 199 pthread->specific_data_count--; 200 pthread->specific[key].data = value; 201 pthread->specific[key].seqno = 202 _thread_keytable[key].seqno; 203 ret = 0; 204 } else 205 ret = EINVAL; 206 } else 207 ret = EINVAL; 208 } else 209 ret = ENOMEM; 210 return (ret); 211 } 212 213 void * 214 _pthread_getspecific(pthread_key_t userkey) 215 { 216 struct pthread *pthread; 217 pthread_key_t key = userkey - 1; 218 const void *data; 219 220 /* Point to the running thread: */ 221 pthread = _get_curthread(); 222 223 /* Check if there is specific data: */ 224 if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) { 225 /* Check if this key has been used before: */ 226 if (_thread_keytable[key].allocated && 227 (pthread->specific[key].seqno == _thread_keytable[key].seqno)) { 228 /* Return the value: */ 229 data = pthread->specific[key].data; 230 } else { 231 /* 232 * This key has not been used before, so return NULL 233 * instead: 234 */ 235 data = NULL; 236 } 237 } else 238 /* No specific data has been created, so just return NULL: */ 239 data = NULL; 240 return (__DECONST(void *, data)); 241 } 242 243 void 244 _thr_tsd_unload(struct dl_phdr_info *phdr_info) 245 { 246 struct pthread *curthread = _get_curthread(); 247 void (*destructor)(void *); 248 int key; 249 250 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 251 for (key = 0; key < PTHREAD_KEYS_MAX; key++) { 252 if (_thread_keytable[key].allocated) { 253 destructor = _thread_keytable[key].destructor; 254 if (destructor != NULL) { 255 if (__elf_phdr_match_addr(phdr_info, destructor)) 256 _thread_keytable[key].destructor = NULL; 257 } 258 } 259 } 260 THR_LOCK_RELEASE(curthread, &_keytable_lock); 261 } 262