lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* Linuxthreads - a simple clone()-based implementation of Posix */ |
| 2 | /* threads for Linux. */ |
| 3 | /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ |
| 4 | /* */ |
| 5 | /* This program is free software; you can redistribute it and/or */ |
| 6 | /* modify it under the terms of the GNU Library General Public License */ |
| 7 | /* as published by the Free Software Foundation; either version 2 */ |
| 8 | /* of the License, or (at your option) any later version. */ |
| 9 | /* */ |
| 10 | /* This program is distributed in the hope that it will be useful, */ |
| 11 | /* but WITHOUT ANY WARRANTY; without even the implied warranty of */ |
| 12 | /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ |
| 13 | /* GNU Library General Public License for more details. */ |
| 14 | |
| 15 | /* Thread-specific data */ |
| 16 | |
| 17 | #include <features.h> |
| 18 | #include <errno.h> |
| 19 | #include <stddef.h> |
| 20 | #include <stdlib.h> |
| 21 | #include "pthread.h" |
| 22 | #include "internals.h" |
| 23 | #include "spinlock.h" |
| 24 | #include "restart.h" |
| 25 | |
| 26 | /* Table of keys. */ |
| 27 | |
| 28 | static struct pthread_key_struct pthread_keys[PTHREAD_KEYS_MAX] = |
| 29 | { { 0, NULL } }; |
| 30 | |
| 31 | /* For debugging purposes put the maximum number of keys in a variable. */ |
| 32 | const int __linuxthreads_pthread_keys_max = PTHREAD_KEYS_MAX; |
| 33 | const int __linuxthreads_pthread_key_2ndlevel_size = PTHREAD_KEY_2NDLEVEL_SIZE; |
| 34 | |
| 35 | /* Mutex to protect access to pthread_keys */ |
| 36 | |
| 37 | static pthread_mutex_t pthread_keys_mutex = PTHREAD_MUTEX_INITIALIZER; |
| 38 | |
| 39 | /* Create a new key */ |
| 40 | |
| 41 | int pthread_key_create(pthread_key_t * key, destr_function destr) |
| 42 | { |
| 43 | int i; |
| 44 | |
| 45 | __pthread_mutex_lock(&pthread_keys_mutex); |
| 46 | for (i = 0; i < PTHREAD_KEYS_MAX; i++) { |
| 47 | if (! pthread_keys[i].in_use) { |
| 48 | /* Mark key in use */ |
| 49 | pthread_keys[i].in_use = 1; |
| 50 | pthread_keys[i].destr = destr; |
| 51 | __pthread_mutex_unlock(&pthread_keys_mutex); |
| 52 | *key = i; |
| 53 | return 0; |
| 54 | } |
| 55 | } |
| 56 | __pthread_mutex_unlock(&pthread_keys_mutex); |
| 57 | return EAGAIN; |
| 58 | } |
| 59 | |
| 60 | /* Delete a key */ |
| 61 | int pthread_key_delete(pthread_key_t key) |
| 62 | { |
| 63 | pthread_descr self = thread_self(); |
| 64 | |
| 65 | __pthread_mutex_lock(&pthread_keys_mutex); |
| 66 | if (key >= PTHREAD_KEYS_MAX || !pthread_keys[key].in_use) { |
| 67 | __pthread_mutex_unlock(&pthread_keys_mutex); |
| 68 | return EINVAL; |
| 69 | } |
| 70 | pthread_keys[key].in_use = 0; |
| 71 | pthread_keys[key].destr = NULL; |
| 72 | |
| 73 | /* Set the value of the key to NULL in all running threads, so |
| 74 | that if the key is reallocated later by pthread_key_create, its |
| 75 | associated values will be NULL in all threads. |
| 76 | Do nothing if no threads have been created yet. */ |
| 77 | if (__pthread_manager_request != -1) |
| 78 | { |
| 79 | pthread_descr th; |
| 80 | unsigned int idx1st, idx2nd; |
| 81 | |
| 82 | idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; |
| 83 | idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; |
| 84 | th = self; |
| 85 | do { |
| 86 | /* If the thread already is terminated don't modify the memory. */ |
| 87 | if (!th->p_terminated && th->p_specific[idx1st] != NULL) |
| 88 | th->p_specific[idx1st][idx2nd] = NULL; |
| 89 | th = th->p_nextlive; |
| 90 | } while (th != self); |
| 91 | } |
| 92 | |
| 93 | __pthread_mutex_unlock(&pthread_keys_mutex); |
| 94 | return 0; |
| 95 | } |
| 96 | |
| 97 | /* Set the value of a key */ |
| 98 | |
| 99 | int pthread_setspecific(pthread_key_t key, const void * pointer) |
| 100 | { |
| 101 | pthread_descr self = thread_self(); |
| 102 | unsigned int idx1st, idx2nd; |
| 103 | |
| 104 | if (key >= PTHREAD_KEYS_MAX || !pthread_keys[key].in_use) |
| 105 | return EINVAL; |
| 106 | idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; |
| 107 | idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; |
| 108 | if (THREAD_GETMEM_NC(self, p_specific[idx1st]) == NULL) { |
| 109 | void *newp = calloc(PTHREAD_KEY_2NDLEVEL_SIZE, sizeof (void *)); |
| 110 | if (newp == NULL) |
| 111 | return ENOMEM; |
| 112 | THREAD_SETMEM_NC(self, p_specific[idx1st], newp); |
| 113 | } |
| 114 | THREAD_GETMEM_NC(self, p_specific[idx1st])[idx2nd] = (void *) pointer; |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | /* Get the value of a key */ |
| 119 | |
| 120 | void * pthread_getspecific(pthread_key_t key) |
| 121 | { |
| 122 | pthread_descr self = thread_self(); |
| 123 | unsigned int idx1st, idx2nd; |
| 124 | |
| 125 | if (key >= PTHREAD_KEYS_MAX) |
| 126 | return NULL; |
| 127 | idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; |
| 128 | idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; |
| 129 | if (THREAD_GETMEM_NC(self, p_specific[idx1st]) == NULL |
| 130 | || !pthread_keys[key].in_use) |
| 131 | return NULL; |
| 132 | return THREAD_GETMEM_NC(self, p_specific[idx1st])[idx2nd]; |
| 133 | } |
| 134 | |
| 135 | /* Call the destruction routines on all keys */ |
| 136 | |
| 137 | void __pthread_destroy_specifics(void) |
| 138 | { |
| 139 | pthread_descr self = thread_self(); |
| 140 | int i, j, round, found_nonzero; |
| 141 | destr_function destr; |
| 142 | void * data; |
| 143 | |
| 144 | for (round = 0, found_nonzero = 1; |
| 145 | found_nonzero && round < PTHREAD_DESTRUCTOR_ITERATIONS; |
| 146 | round++) { |
| 147 | found_nonzero = 0; |
| 148 | for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) |
| 149 | if (THREAD_GETMEM_NC(self, p_specific[i]) != NULL) |
| 150 | for (j = 0; j < PTHREAD_KEY_2NDLEVEL_SIZE; j++) { |
| 151 | destr = pthread_keys[i * PTHREAD_KEY_2NDLEVEL_SIZE + j].destr; |
| 152 | data = THREAD_GETMEM_NC(self, p_specific[i])[j]; |
| 153 | if (destr != NULL && data != NULL) { |
| 154 | THREAD_GETMEM_NC(self, p_specific[i])[j] = NULL; |
| 155 | destr(data); |
| 156 | found_nonzero = 1; |
| 157 | } |
| 158 | } |
| 159 | } |
| 160 | __pthread_lock(THREAD_GETMEM(self, p_lock), self); |
| 161 | for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) { |
| 162 | if (THREAD_GETMEM_NC(self, p_specific[i]) != NULL) { |
| 163 | free(THREAD_GETMEM_NC(self, p_specific[i])); |
| 164 | THREAD_SETMEM_NC(self, p_specific[i], NULL); |
| 165 | } |
| 166 | } |
| 167 | __pthread_unlock(THREAD_GETMEM(self, p_lock)); |
| 168 | } |
| 169 | |
| 170 | #ifndef USE___THREAD |
| 171 | |
| 172 | /* Thread-specific data for libc. */ |
| 173 | |
| 174 | int |
| 175 | __pthread_internal_tsd_set (int key, const void * pointer) |
| 176 | { |
| 177 | pthread_descr self = thread_self(); |
| 178 | |
| 179 | THREAD_SETMEM_NC(self, p_libc_specific[key], (void *) pointer); |
| 180 | return 0; |
| 181 | } |
| 182 | |
| 183 | void * |
| 184 | __pthread_internal_tsd_get (int key) |
| 185 | { |
| 186 | pthread_descr self = thread_self(); |
| 187 | |
| 188 | return THREAD_GETMEM_NC(self, p_libc_specific[key]); |
| 189 | } |
| 190 | |
| 191 | void ** __attribute__ ((__const__)) |
| 192 | __pthread_internal_tsd_address (int key) |
| 193 | { |
| 194 | pthread_descr self = thread_self(); |
| 195 | return &self->p_libc_specific[key]; |
| 196 | } |
| 197 | |
| 198 | #endif |