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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by John Birrell. 16 * 4. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD$ 33 */ 34 #include <signal.h> 35 #include <stdlib.h> 36 #include <string.h> 37 #include <errno.h> 38 #include <pthread.h> 39 #include "thr_private.h" 40 41 struct pthread_key { 42 spinlock_t lock; 43 volatile int allocated; 44 volatile int count; 45 int seqno; 46 void (*destructor) (); 47 }; 48 49 /* Static variables: */ 50 static struct pthread_key key_table[PTHREAD_KEYS_MAX]; 51 52 __weak_reference(_pthread_key_create, pthread_key_create); 53 __weak_reference(_pthread_key_delete, pthread_key_delete); 54 __weak_reference(_pthread_getspecific, pthread_getspecific); 55 __weak_reference(_pthread_setspecific, pthread_setspecific); 56 57 58 int 59 _pthread_key_create(pthread_key_t * key, void (*destructor) (void *)) 60 { 61 for ((*key) = 0; (*key) < PTHREAD_KEYS_MAX; (*key)++) { 62 /* Lock the key table entry: */ 63 _SPINLOCK(&key_table[*key].lock); 64 65 if (key_table[(*key)].allocated == 0) { 66 key_table[(*key)].allocated = 1; 67 key_table[(*key)].destructor = destructor; 68 key_table[(*key)].seqno++; 69 70 /* Unlock the key table entry: */ 71 _SPINUNLOCK(&key_table[*key].lock); 72 return (0); 73 } 74 75 /* Unlock the key table entry: */ 76 _SPINUNLOCK(&key_table[*key].lock); 77 } 78 return (EAGAIN); 79 } 80 81 int 82 _pthread_key_delete(pthread_key_t key) 83 { 84 int ret = 0; 85 86 if (key < PTHREAD_KEYS_MAX) { 87 /* Lock the key table entry: */ 88 _SPINLOCK(&key_table[key].lock); 89 90 if (key_table[key].allocated) 91 key_table[key].allocated = 0; 92 else 93 ret = EINVAL; 94 95 /* Unlock the key table entry: */ 96 _SPINUNLOCK(&key_table[key].lock); 97 } else 98 ret = EINVAL; 99 return (ret); 100 } 101 102 void 103 _thread_cleanupspecific(void) 104 { 105 void *data = NULL; 106 int key; 107 int itr; 108 void (*destructor)( void *); 109 110 for (itr = 0; itr < PTHREAD_DESTRUCTOR_ITERATIONS; itr++) { 111 for (key = 0; key < PTHREAD_KEYS_MAX; key++) { 112 if (curthread->specific_data_count > 0) { 113 /* Lock the key table entry: */ 114 _SPINLOCK(&key_table[key].lock); 115 destructor = NULL; 116 117 if (key_table[key].allocated && 118 (curthread->specific[key].data != NULL)) { 119 if (curthread->specific[key].seqno == 120 key_table[key].seqno) { 121 data = (void *) curthread->specific[key].data; 122 destructor = key_table[key].destructor; 123 } 124 curthread->specific[key].data = NULL; 125 curthread->specific_data_count--; 126 } 127 128 /* Unlock the key table entry: */ 129 _SPINUNLOCK(&key_table[key].lock); 130 131 /* 132 * If there is a destructore, call it 133 * with the key table entry unlocked: 134 */ 135 if (destructor) 136 destructor(data); 137 } else { 138 free(curthread->specific); 139 curthread->specific = NULL; 140 return; 141 } 142 } 143 } 144 if (curthread->specific != NULL) { 145 free(curthread->specific); 146 curthread->specific = NULL; 147 } 148 } 149 150 static inline struct pthread_specific_elem * 151 pthread_key_allocate_data(void) 152 { 153 struct pthread_specific_elem *new_data; 154 155 new_data = (struct pthread_specific_elem *) 156 malloc(sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 157 if (new_data != NULL) { 158 memset((void *) new_data, 0, 159 sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); 160 } 161 return (new_data); 162 } 163 164 int 165 _pthread_setspecific(pthread_key_t key, const void *value) 166 { 167 int ret = 0; 168 pthread_t pthread = curthread; 169 170 if ((pthread->specific) || 171 (pthread->specific = pthread_key_allocate_data())) { 172 if (key < PTHREAD_KEYS_MAX) { 173 if (key_table[key].allocated) { 174 if (pthread->specific[key].data == NULL) { 175 if (value != NULL) 176 pthread->specific_data_count++; 177 } else { 178 if (value == NULL) 179 pthread->specific_data_count--; 180 } 181 pthread->specific[key].data = value; 182 pthread->specific[key].seqno = 183 key_table[key].seqno; 184 ret = 0; 185 } else 186 ret = EINVAL; 187 } else 188 ret = EINVAL; 189 } else 190 ret = ENOMEM; 191 return (ret); 192 } 193 194 void * 195 _pthread_getspecific(pthread_key_t key) 196 { 197 pthread_t pthread = curthread; 198 void *data; 199 200 /* Check if there is specific data: */ 201 if (pthread->specific != NULL && key < PTHREAD_KEYS_MAX) { 202 /* Check if this key has been used before: */ 203 if (key_table[key].allocated && 204 (pthread->specific[key].seqno == key_table[key].seqno)) { 205 /* Return the value: */ 206 data = (void *) pthread->specific[key].data; 207 } else { 208 /* 209 * This key has not been used before, so return NULL 210 * instead: 211 */ 212 data = NULL; 213 } 214 } else 215 /* No specific data has been created, so just return NULL: */ 216 data = NULL; 217 return (data); 218 } 219