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 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "namespace.h" 34 #include <sys/mman.h> 35 #include <signal.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <errno.h> 39 #include <pthread.h> 40 #include "un-namespace.h" 41 #include "libc_private.h" 42 43 #include "thr_private.h" 44 45 static struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; 46 47 __weak_reference(_pthread_key_create, pthread_key_create); 48 __weak_reference(_pthread_key_delete, pthread_key_delete); 49 __weak_reference(_pthread_getspecific, pthread_getspecific); 50 __weak_reference(_pthread_setspecific, pthread_setspecific); 51 52 53 int 54 _pthread_key_create(pthread_key_t *key, void (*destructor)(void *)) 55 { 56 struct pthread *curthread; 57 int i; 58 59 _thr_check_init(); 60 61 curthread = _get_curthread(); 62 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 THR_LOCK_RELEASE(curthread, &_keytable_lock); 72 *key = i + 1; 73 return (0); 74 } 75 76 } 77 THR_LOCK_RELEASE(curthread, &_keytable_lock); 78 return (EAGAIN); 79 } 80 81 int 82 _pthread_key_delete(pthread_key_t userkey) 83 { 84 struct pthread *curthread; 85 int key, ret; 86 87 key = userkey - 1; 88 if ((unsigned int)key >= PTHREAD_KEYS_MAX) 89 return (EINVAL); 90 curthread = _get_curthread(); 91 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 92 if (_thread_keytable[key].allocated) { 93 _thread_keytable[key].allocated = 0; 94 ret = 0; 95 } else { 96 ret = EINVAL; 97 } 98 THR_LOCK_RELEASE(curthread, &_keytable_lock); 99 return (ret); 100 } 101 102 void 103 _thread_cleanupspecific(void) 104 { 105 struct pthread *curthread; 106 void (*destructor)(void *); 107 const void *data; 108 int i, key; 109 110 curthread = _get_curthread(); 111 if (curthread->specific == NULL) 112 return; 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 = curthread->specific[key].data; 125 destructor = _thread_keytable[key]. 126 destructor; 127 } 128 curthread->specific[key].data = NULL; 129 curthread->specific_data_count--; 130 } else if (curthread->specific[key].data != NULL) { 131 /* 132 * This can happen if the key is 133 * deleted via pthread_key_delete 134 * without first setting the value to 135 * NULL in all threads. POSIX says 136 * that the destructor is not invoked 137 * in this case. 138 */ 139 curthread->specific[key].data = NULL; 140 curthread->specific_data_count--; 141 } 142 143 /* 144 * If there is a destructor, call it with the 145 * key table entry unlocked. 146 */ 147 if (destructor != NULL) { 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 munmap(curthread->specific, PTHREAD_KEYS_MAX * sizeof(struct 156 pthread_specific_elem)); 157 curthread->specific = NULL; 158 if (curthread->specific_data_count > 0) { 159 stderr_debug("Thread %p has exited with leftover " 160 "thread-specific data after %d destructor iterations\n", 161 curthread, PTHREAD_DESTRUCTOR_ITERATIONS); 162 } 163 } 164 165 int 166 _pthread_setspecific(pthread_key_t userkey, const void *value) 167 { 168 struct pthread *pthread; 169 void *tmp; 170 pthread_key_t key; 171 172 key = userkey - 1; 173 if ((unsigned int)key >= PTHREAD_KEYS_MAX || 174 !_thread_keytable[key].allocated) 175 return (EINVAL); 176 177 pthread = _get_curthread(); 178 if (pthread->specific == NULL) { 179 tmp = mmap(NULL, PTHREAD_KEYS_MAX * 180 sizeof(struct pthread_specific_elem), 181 PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); 182 if (tmp == MAP_FAILED) 183 return (ENOMEM); 184 pthread->specific = tmp; 185 } 186 if (pthread->specific[key].data == NULL) { 187 if (value != NULL) 188 pthread->specific_data_count++; 189 } else if (value == NULL) 190 pthread->specific_data_count--; 191 pthread->specific[key].data = value; 192 pthread->specific[key].seqno = _thread_keytable[key].seqno; 193 return (0); 194 } 195 196 void * 197 _pthread_getspecific(pthread_key_t userkey) 198 { 199 struct pthread *pthread; 200 const void *data; 201 pthread_key_t key; 202 203 /* Check if there is specific data. */ 204 key = userkey - 1; 205 if ((unsigned int)key >= PTHREAD_KEYS_MAX) 206 return (NULL); 207 208 pthread = _get_curthread(); 209 /* Check if this key has been used before. */ 210 if (_thread_keytable[key].allocated && pthread->specific != NULL && 211 pthread->specific[key].seqno == _thread_keytable[key].seqno) { 212 /* Return the value: */ 213 data = pthread->specific[key].data; 214 } else { 215 /* 216 * This key has not been used before, so return NULL 217 * instead. 218 */ 219 data = NULL; 220 } 221 return (__DECONST(void *, data)); 222 } 223 224 void 225 _thr_tsd_unload(struct dl_phdr_info *phdr_info) 226 { 227 struct pthread *curthread; 228 void (*destructor)(void *); 229 int key; 230 231 curthread = _get_curthread(); 232 THR_LOCK_ACQUIRE(curthread, &_keytable_lock); 233 for (key = 0; key < PTHREAD_KEYS_MAX; key++) { 234 if (!_thread_keytable[key].allocated) 235 continue; 236 destructor = _thread_keytable[key].destructor; 237 if (destructor == NULL) 238 continue; 239 if (__elf_phdr_match_addr(phdr_info, destructor)) 240 _thread_keytable[key].destructor = NULL; 241 } 242 THR_LOCK_RELEASE(curthread, &_keytable_lock); 243 } 244