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Diffstat (limited to 'lib/libthr/thread/thr_spec.c')
| -rw-r--r-- | lib/libthr/thread/thr_spec.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/lib/libthr/thread/thr_spec.c b/lib/libthr/thread/thr_spec.c new file mode 100644 index 0000000..07ef387 --- /dev/null +++ b/lib/libthr/thread/thr_spec.c @@ -0,0 +1,225 @@ +/* + * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by John Birrell. + * 4. Neither the name of the author nor the names of any co-contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <pthread.h> +#include "thr_private.h" + +struct pthread_key { + spinlock_t lock; + volatile int allocated; + volatile int count; + int seqno; + void (*destructor) (); +}; + +/* Static variables: */ +static struct pthread_key key_table[PTHREAD_KEYS_MAX]; + +__weak_reference(_pthread_key_create, pthread_key_create); +__weak_reference(_pthread_key_delete, pthread_key_delete); +__weak_reference(_pthread_getspecific, pthread_getspecific); +__weak_reference(_pthread_setspecific, pthread_setspecific); + + +int +_pthread_key_create(pthread_key_t * key, void (*destructor) (void *)) +{ + for ((*key) = 0; (*key) < PTHREAD_KEYS_MAX; (*key)++) { + /* Lock the key table entry: */ + _SPINLOCK(&key_table[*key].lock); + + if (key_table[(*key)].allocated == 0) { + key_table[(*key)].allocated = 1; + key_table[(*key)].destructor = destructor; + key_table[(*key)].seqno++; + + /* Unlock the key table entry: */ + _SPINUNLOCK(&key_table[*key].lock); + return (0); + } + + /* Unlock the key table entry: */ + _SPINUNLOCK(&key_table[*key].lock); + } + return (EAGAIN); +} + +int +_pthread_key_delete(pthread_key_t key) +{ + int ret = 0; + + if (key < PTHREAD_KEYS_MAX) { + /* Lock the key table entry: */ + _SPINLOCK(&key_table[key].lock); + + if (key_table[key].allocated) + key_table[key].allocated = 0; + else + ret = EINVAL; + + /* Unlock the key table entry: */ + _SPINUNLOCK(&key_table[key].lock); + } else + ret = EINVAL; + return (ret); +} + +void +_thread_cleanupspecific(void) +{ + struct pthread *curthread = _get_curthread(); + void *data = NULL; + int key; + int itr; + void (*destructor)( void *); + + for (itr = 0; itr < PTHREAD_DESTRUCTOR_ITERATIONS; itr++) { + for (key = 0; key < PTHREAD_KEYS_MAX; key++) { + if (curthread->specific_data_count > 0) { + /* Lock the key table entry: */ + _SPINLOCK(&key_table[key].lock); + destructor = NULL; + + if (key_table[key].allocated && + (curthread->specific[key].data != NULL)) { + if (curthread->specific[key].seqno == + key_table[key].seqno) { + data = (void *) curthread->specific[key].data; + destructor = key_table[key].destructor; + } + curthread->specific[key].data = NULL; + curthread->specific_data_count--; + } + + /* Unlock the key table entry: */ + _SPINUNLOCK(&key_table[key].lock); + + /* + * If there is a destructore, call it + * with the key table entry unlocked: + */ + if (destructor) + destructor(data); + } else { + free(curthread->specific); + curthread->specific = NULL; + return; + } + } + } + if (curthread->specific != NULL) { + free(curthread->specific); + curthread->specific = NULL; + } +} + +static inline struct pthread_specific_elem * +pthread_key_allocate_data(void) +{ + struct pthread_specific_elem *new_data; + + new_data = (struct pthread_specific_elem *) + malloc(sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); + if (new_data != NULL) { + memset((void *) new_data, 0, + sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); + } + return (new_data); +} + +int +_pthread_setspecific(pthread_key_t key, const void *value) +{ + struct pthread *pthread; + int ret = 0; + + /* Point to the running thread: */ + pthread = _get_curthread(); + + if ((pthread->specific) || + (pthread->specific = pthread_key_allocate_data())) { + if (key < PTHREAD_KEYS_MAX) { + if (key_table[key].allocated) { + if (pthread->specific[key].data == NULL) { + if (value != NULL) + pthread->specific_data_count++; + } else { + if (value == NULL) + pthread->specific_data_count--; + } + pthread->specific[key].data = value; + pthread->specific[key].seqno = + key_table[key].seqno; + ret = 0; + } else + ret = EINVAL; + } else + ret = EINVAL; + } else + ret = ENOMEM; + return (ret); +} + +void * +_pthread_getspecific(pthread_key_t key) +{ + struct pthread *pthread; + void *data; + + /* Point to the running thread: */ + pthread = _get_curthread(); + + /* Check if there is specific data: */ + if (pthread->specific != NULL && key < PTHREAD_KEYS_MAX) { + /* Check if this key has been used before: */ + if (key_table[key].allocated && + (pthread->specific[key].seqno == key_table[key].seqno)) { + /* Return the value: */ + data = (void *) pthread->specific[key].data; + } else { + /* + * This key has not been used before, so return NULL + * instead: + */ + data = NULL; + } + } else + /* No specific data has been created, so just return NULL: */ + data = NULL; + return (data); +} |
