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/* 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 <errno.h>
#include <stddef.h>
#include <stdlib.h>
#include "pthread.h"
#include "internals.h"
#include "spinlock.h"
#include "restart.h"
#include <bits/libc-lock.h>
/* Table of keys. */
static struct pthread_key_struct pthread_keys[PTHREAD_KEYS_MAX] =
{ { 0, NULL } };
/* For debugging purposes put the maximum number of keys in a variable. */
const int __linuxthreads_pthread_keys_max = PTHREAD_KEYS_MAX;
const int __linuxthreads_pthread_key_2ndlevel_size = PTHREAD_KEY_2NDLEVEL_SIZE;
/* 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;
}
strong_alias (__pthread_key_create, pthread_key_create)
/* Reset deleted key's value to NULL in each live thread.
* NOTE: this executes in the context of the thread manager! */
struct pthread_key_delete_helper_args {
/* Damn, we need lexical closures in C! ;) */
unsigned int idx1st, idx2nd;
pthread_descr self;
};
static void pthread_key_delete_helper(void *arg, pthread_descr th)
{
struct pthread_key_delete_helper_args *args = arg;
unsigned int idx1st = args->idx1st;
unsigned int idx2nd = args->idx2nd;
pthread_descr self = args->self;
if (self == 0)
self = args->self = thread_self();
if (!th->p_terminated) {
/* pthread_exit() may try to free th->p_specific[idx1st] concurrently. */
__pthread_lock(THREAD_GETMEM(th, p_lock), self);
if (th->p_specific[idx1st] != NULL)
th->p_specific[idx1st][idx2nd] = NULL;
__pthread_unlock(THREAD_GETMEM(th, p_lock));
}
}
/* Delete a key */
int pthread_key_delete(pthread_key_t key)
{
pthread_descr self = thread_self();
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.
Do nothing if no threads have been created yet. */
if (__pthread_manager_request != -1)
{
struct pthread_key_delete_helper_args args;
struct pthread_request request;
args.idx1st = key / PTHREAD_KEY_2NDLEVEL_SIZE;
args.idx2nd = key % PTHREAD_KEY_2NDLEVEL_SIZE;
args.self = 0;
request.req_thread = self;
request.req_kind = REQ_FOR_EACH_THREAD;
request.req_args.for_each.arg = &args;
request.req_args.for_each.fn = pthread_key_delete_helper;
TEMP_FAILURE_RETRY(__libc_write(__pthread_manager_request,
(char *) &request, sizeof(request)));
suspend(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 (THREAD_GETMEM_NC(self, p_specific[idx1st]) == NULL) {
void *newp = calloc(PTHREAD_KEY_2NDLEVEL_SIZE, sizeof (void *));
if (newp == NULL)
return ENOMEM;
THREAD_SETMEM_NC(self, p_specific[idx1st], newp);
}
THREAD_GETMEM_NC(self, p_specific[idx1st])[idx2nd] = (void *) pointer;
return 0;
}
strong_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 (THREAD_GETMEM_NC(self, p_specific[idx1st]) == NULL
|| !pthread_keys[key].in_use)
return NULL;
return THREAD_GETMEM_NC(self, p_specific[idx1st])[idx2nd];
}
strong_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 (THREAD_GETMEM_NC(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 = THREAD_GETMEM_NC(self, p_specific[i])[j];
if (destr != NULL && data != NULL) {
THREAD_GETMEM_NC(self, p_specific[i])[j] = NULL;
destr(data);
found_nonzero = 1;
}
}
}
__pthread_lock(THREAD_GETMEM(self, p_lock), self);
for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) {
if (THREAD_GETMEM_NC(self, p_specific[i]) != NULL) {
free(THREAD_GETMEM_NC(self, p_specific[i]));
THREAD_SETMEM_NC(self, p_specific[i], NULL);
}
}
__pthread_unlock(THREAD_GETMEM(self, p_lock));
}
#if !(USE_TLS && HAVE___THREAD)
/* Thread-specific data for libc. */
static int
libc_internal_tsd_set(enum __libc_tsd_key_t key, const void * pointer)
{
pthread_descr self = thread_self();
THREAD_SETMEM_NC(self, p_libc_specific[key], (void *) pointer);
return 0;
}
int (*__libc_internal_tsd_set)(enum __libc_tsd_key_t key, const void * pointer)
= libc_internal_tsd_set;
static void *
libc_internal_tsd_get(enum __libc_tsd_key_t key)
{
pthread_descr self = thread_self();
return THREAD_GETMEM_NC(self, p_libc_specific[key]);
}
void * (*__libc_internal_tsd_get)(enum __libc_tsd_key_t key)
= libc_internal_tsd_get;
#endif
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