1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the author nor the names of any co-contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "namespace.h" 36 #include <sys/mman.h> 37 #include <signal.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <errno.h> 41 #include <pthread.h> 42 #include "un-namespace.h" 43 #include "libc_private.h" 44 45 #include "thr_private.h" 46 47 /* Used in symbol lookup of libthread_db */ 48 struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; 49 50 __weak_reference(_thr_key_create, pthread_key_create); 51 __weak_reference(_thr_key_create, _pthread_key_create); 52 __weak_reference(_thr_key_delete, pthread_key_delete); 53 __weak_reference(_thr_key_delete, _pthread_key_delete); 54 __weak_reference(_thr_getspecific, pthread_getspecific); 55 __weak_reference(_thr_getspecific, _pthread_getspecific); 56 __weak_reference(_thr_setspecific, pthread_setspecific); 57 __weak_reference(_thr_setspecific, _pthread_setspecific); 58 59 int 60 _thr_key_create(pthread_key_t *key, void (*destructor)(void *)) 61 { 62 struct pthread *curthread; 63 int i; 64 65 _thr_check_init(); 66 67 curthread = _get_curthread(); 68 69 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 70 for (i = 0; i < PTHREAD_KEYS_MAX; i++) { 71 72 if (_thread_keytable[i].allocated == 0) { 73 _thread_keytable[i].allocated = 1; 74 _thread_keytable[i].destructor = destructor; 75 _thread_keytable[i].seqno++; 76 77 THR_LOCK_RELEASE(curthread, &_keytable_lock); 78 *key = i + 1; 79 return (0); 80 } 81 82 } 83 THR_LOCK_RELEASE(curthread, &_keytable_lock); 84 return (EAGAIN); 85 } 86 87 int 88 _thr_key_delete(pthread_key_t userkey) 89 { 90 struct pthread *curthread; 91 int key, ret; 92 93 key = userkey - 1; 94 if ((unsigned int)key >= PTHREAD_KEYS_MAX) 95 return (EINVAL); 96 curthread = _get_curthread(); 97 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 98 if (_thread_keytable[key].allocated) { 99 _thread_keytable[key].allocated = 0; 100 ret = 0; 101 } else { 102 ret = EINVAL; 103 } 104 THR_LOCK_RELEASE(curthread, &_keytable_lock); 105 return (ret); 106 } 107 108 void 109 _thread_cleanupspecific(void) 110 { 111 struct pthread *curthread; 112 void (*destructor)(void *); 113 const void *data; 114 int i, key; 115 116 curthread = _get_curthread(); 117 if (curthread->specific == NULL) 118 return; 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]. 132 destructor; 133 } 134 curthread->specific[key].data = NULL; 135 curthread->specific_data_count--; 136 } else if (curthread->specific[key].data != NULL) { 137 /* 138 * This can happen if the key is 139 * deleted via pthread_key_delete 140 * without first setting the value to 141 * NULL in all threads. POSIX says 142 * that the destructor is not invoked 143 * in this case. 144 */ 145 curthread->specific[key].data = NULL; 146 curthread->specific_data_count--; 147 } 148 149 /* 150 * If there is a destructor, call it with the 151 * key table entry unlocked. 152 */ 153 if (destructor != NULL) { 154 THR_LOCK_RELEASE(curthread, &_keytable_lock); 155 destructor(__DECONST(void *, data)); 156 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 157 } 158 } 159 } 160 THR_LOCK_RELEASE(curthread, &_keytable_lock); 161 __thr_free(curthread->specific); 162 curthread->specific = NULL; 163 if (curthread->specific_data_count > 0) { 164 stderr_debug("Thread %p has exited with leftover " 165 "thread-specific data after %d destructor iterations\n", 166 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 167 } 168 } 169 170 int 171 _thr_setspecific(pthread_key_t userkey, const void *value) 172 { 173 struct pthread *pthread; 174 void *tmp; 175 pthread_key_t key; 176 177 key = userkey - 1; 178 if ((unsigned int)key >= PTHREAD_KEYS_MAX || 179 !_thread_keytable[key].allocated) 180 return (EINVAL); 181 182 pthread = _get_curthread(); 183 if (pthread->specific == NULL) { 184 tmp = __thr_calloc(PTHREAD_KEYS_MAX, 185 sizeof(struct pthread_specific_elem)); 186 if (tmp == NULL) 187 return (ENOMEM); 188 pthread->specific = tmp; 189 } 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 = _thread_keytable[key].seqno; 197 return (0); 198 } 199 200 void * 201 _thr_getspecific(pthread_key_t userkey) 202 { 203 struct pthread *pthread; 204 const void *data; 205 pthread_key_t key; 206 207 /* Check if there is specific data. */ 208 key = userkey - 1; 209 if ((unsigned int)key >= PTHREAD_KEYS_MAX) 210 return (NULL); 211 212 pthread = _get_curthread(); 213 /* Check if this key has been used before. */ 214 if (_thread_keytable[key].allocated && pthread->specific != NULL && 215 pthread->specific[key].seqno == _thread_keytable[key].seqno) { 216 /* Return the value: */ 217 data = pthread->specific[key].data; 218 } else { 219 /* 220 * This key has not been used before, so return NULL 221 * instead. 222 */ 223 data = NULL; 224 } 225 return (__DECONST(void *, data)); 226 } 227 228 void 229 _thr_tsd_unload(struct dl_phdr_info *phdr_info) 230 { 231 struct pthread *curthread; 232 void (*destructor)(void *); 233 int key; 234 235 curthread = _get_curthread(); 236 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 237 for (key = 0; key < PTHREAD_KEYS_MAX; key++) { 238 if (!_thread_keytable[key].allocated) 239 continue; 240 destructor = _thread_keytable[key].destructor; 241 if (destructor == NULL) 242 continue; 243 if (__elf_phdr_match_addr(phdr_info, destructor)) 244 _thread_keytable[key].destructor = NULL; 245 } 246 THR_LOCK_RELEASE(curthread, &_keytable_lock); 247 } 248