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Diffstat (limited to 'linuxthreads/specific.c')
| -rw-r--r-- | linuxthreads/specific.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/linuxthreads/specific.c b/linuxthreads/specific.c new file mode 100644 index 0000000..71f1ede --- /dev/null +++ b/linuxthreads/specific.c @@ -0,0 +1,174 @@ +/* Linuxthreads - a simple clone()-based implementation of Posix */ +/* threads for Linux. */ +/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ +/* */ +/* This program is free software; you can redistribute it and/or */ +/* modify it under the terms of the GNU Library General Public License */ +/* as published by the Free Software Foundation; either version 2 */ +/* of the License, or (at your option) any later version. */ +/* */ +/* This program is distributed in the hope that it will be useful, */ +/* but WITHOUT ANY WARRANTY; without even the implied warranty of */ +/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ +/* GNU Library General Public License for more details. */ + +/* Thread-specific data */ + +#include <stddef.h> +#include <stdlib.h> +#include "pthread.h" +#include "internals.h" + +typedef void (*destr_function)(void *); + +/* Table of keys. */ + +struct pthread_key_struct { + int in_use; /* already allocated? */ + destr_function destr; /* destruction routine */ +}; + +static struct pthread_key_struct pthread_keys[PTHREAD_KEYS_MAX] = + { { 0, NULL } }; + +/* Mutex to protect access to pthread_keys */ + +static pthread_mutex_t pthread_keys_mutex = PTHREAD_MUTEX_INITIALIZER; + +/* Create a new key */ + +int __pthread_key_create(pthread_key_t * key, destr_function destr) +{ + int i; + + pthread_mutex_lock(&pthread_keys_mutex); + for (i = 0; i < PTHREAD_KEYS_MAX; i++) { + if (! pthread_keys[i].in_use) { + /* Mark key in use */ + pthread_keys[i].in_use = 1; + pthread_keys[i].destr = destr; + pthread_mutex_unlock(&pthread_keys_mutex); + *key = i; + return 0; + } + } + pthread_mutex_unlock(&pthread_keys_mutex); + return EAGAIN; +} +weak_alias (__pthread_key_create, pthread_key_create) + +/* Delete a key */ + +int pthread_key_delete(pthread_key_t key) +{ + pthread_descr self = thread_self(); + pthread_descr th; + unsigned int idx1st, idx2nd; + + pthread_mutex_lock(&pthread_keys_mutex); + if (key >= PTHREAD_KEYS_MAX || !pthread_keys[key].in_use) { + pthread_mutex_unlock(&pthread_keys_mutex); + return EINVAL; + } + pthread_keys[key].in_use = 0; + pthread_keys[key].destr = NULL; + /* Set the value of the key to NULL in all running threads, so that + if the key is reallocated later by pthread_key_create, its + associated values will be NULL in all threads. */ + idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; + idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; + th = self; + do { + if (th->p_specific[idx1st] != NULL) + th->p_specific[idx1st][idx2nd] = NULL; + th = th->p_nextlive; + } while (th != self); + pthread_mutex_unlock(&pthread_keys_mutex); + return 0; +} + +/* Set the value of a key */ + +int __pthread_setspecific(pthread_key_t key, const void * pointer) +{ + pthread_descr self = thread_self(); + unsigned int idx1st, idx2nd; + + if (key >= PTHREAD_KEYS_MAX || !pthread_keys[key].in_use) + return EINVAL; + idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; + idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; + if (self->p_specific[idx1st] == NULL) { + self->p_specific[idx1st] = + calloc(PTHREAD_KEY_2NDLEVEL_SIZE, sizeof (void *)); + if (self->p_specific[idx1st] == NULL) + return ENOMEM; + } + self->p_specific[idx1st][idx2nd] = (void *) pointer; + return 0; +} +weak_alias (__pthread_setspecific, pthread_setspecific) + +/* Get the value of a key */ + +void * __pthread_getspecific(pthread_key_t key) +{ + pthread_descr self = thread_self(); + unsigned int idx1st, idx2nd; + + if (key >= PTHREAD_KEYS_MAX) + return NULL; + idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE; + idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE; + if (self->p_specific[idx1st] == NULL || !pthread_keys[key].in_use) + return NULL; + return self->p_specific[idx1st][idx2nd]; +} +weak_alias (__pthread_getspecific, pthread_getspecific) + +/* Call the destruction routines on all keys */ + +void __pthread_destroy_specifics() +{ + pthread_descr self = thread_self(); + int i, j, round, found_nonzero; + destr_function destr; + void * data; + + for (round = 0, found_nonzero = 1; + found_nonzero && round < PTHREAD_DESTRUCTOR_ITERATIONS; + round++) { + found_nonzero = 0; + for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) + if (self->p_specific[i] != NULL) + for (j = 0; j < PTHREAD_KEY_2NDLEVEL_SIZE; j++) { + destr = pthread_keys[i * PTHREAD_KEY_2NDLEVEL_SIZE + j].destr; + data = self->p_specific[i][j]; + if (destr != NULL && data != NULL) { + self->p_specific[i][j] = NULL; + destr(data); + found_nonzero = 1; + } + } + } + for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) { + if (self->p_specific[i] != NULL) free(self->p_specific[i]); + } +} + +/* Thread-specific data for libc. */ + +int __libc_internal_tsd_set(enum __libc_tsd_key_t key, const void * pointer) +{ + pthread_descr self = thread_self(); + + self->p_libc_specific[key] = (void *) pointer; + return 0; +} + +void * __libc_internal_tsd_get(enum __libc_tsd_key_t key) +{ + pthread_descr self = thread_self(); + + return self->p_libc_specific[key]; +} |