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. Neither the name of the author nor the names of any co-contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31
32#include "namespace.h"
33#include <signal.h>
34#include <stdlib.h>
35#include <string.h>
36#include <errno.h>
37#include <pthread.h>
38#include "un-namespace.h"
39#include "thr_private.h"
40
41
42struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX];
43
44__weak_reference(_pthread_key_create, pthread_key_create);
45__weak_reference(_pthread_key_delete, pthread_key_delete);
46__weak_reference(_pthread_getspecific, pthread_getspecific);
47__weak_reference(_pthread_setspecific, pthread_setspecific);
48
49
50int
51_pthread_key_create(pthread_key_t *key, void (*destructor) (void *))
52{
53	struct pthread *curthread;
54	int i;
55
56	if (_thr_initial == NULL)
57		_libpthread_init(NULL);
58	curthread = _get_curthread();
59
60	/* Lock the key table: */
61	THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
62	for (i = 0; i < PTHREAD_KEYS_MAX; i++) {
63
64		if (_thread_keytable[i].allocated == 0) {
65			_thread_keytable[i].allocated = 1;
66			_thread_keytable[i].destructor = destructor;
67			_thread_keytable[i].seqno++;
68
69			/* Unlock the key table: */
70			THR_LOCK_RELEASE(curthread, &_keytable_lock);
71			*key = i;
72			return (0);
73		}
74
75	}
76	/* Unlock the key table: */
77	THR_LOCK_RELEASE(curthread, &_keytable_lock);
78	return (EAGAIN);
79}
80
81int
82_pthread_key_delete(pthread_key_t key)
83{
84	struct pthread *curthread = _get_curthread();
85	int ret = 0;
86
87	if ((unsigned int)key < PTHREAD_KEYS_MAX) {
88		/* Lock the key table: */
89		THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
90
91		if (_thread_keytable[key].allocated)
92			_thread_keytable[key].allocated = 0;
93		else
94			ret = EINVAL;
95
96		/* Unlock the key table: */
97		THR_LOCK_RELEASE(curthread, &_keytable_lock);
98	} else
99		ret = EINVAL;
100	return (ret);
101}
102
103void
104_thread_cleanupspecific(void)
105{
106	struct pthread	*curthread = _get_curthread();
107	const_key_destructor_t destructor;
108	const void	*data = NULL;
109	int		key;
110	int		i;
111
112	if (curthread->specific == NULL)
113		return;
114
115	/* Lock the key table: */
116	THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
117	for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) &&
118	    (curthread->specific_data_count > 0); i++) {
119		for (key = 0; (key < PTHREAD_KEYS_MAX) &&
120		    (curthread->specific_data_count > 0); key++) {
121			destructor = NULL;
122
123			if (_thread_keytable[key].allocated &&
124			    (curthread->specific[key].data != NULL)) {
125				if (curthread->specific[key].seqno ==
126				    _thread_keytable[key].seqno) {
127					data = curthread->specific[key].data;
128					destructor = (const_key_destructor_t)
129					    _thread_keytable[key].destructor;
130				}
131				curthread->specific[key].data = NULL;
132				curthread->specific_data_count--;
133			}
134
135			/*
136			 * If there is a destructore, call it
137			 * with the key table entry unlocked:
138			 */
139			if (destructor != NULL) {
140				/*
141				 * Don't hold the lock while calling the
142				 * destructor:
143				 */
144				THR_LOCK_RELEASE(curthread, &_keytable_lock);
145				destructor(data);
146				THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
147			}
148		}
149	}
150	THR_LOCK_RELEASE(curthread, &_keytable_lock);
151	free(curthread->specific);
152	curthread->specific = NULL;
153	if (curthread->specific_data_count > 0)
154		stderr_debug("Thread %p has exited with leftover "
155		    "thread-specific data after %d destructor iterations\n",
156		    curthread, PTHREAD_DESTRUCTOR_ITERATIONS);
157}
158
159static inline struct pthread_specific_elem *
160pthread_key_allocate_data(void)
161{
162	struct pthread_specific_elem *new_data;
163
164	new_data = (struct pthread_specific_elem *)
165	    malloc(sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX);
166	if (new_data != NULL) {
167		memset((void *) new_data, 0,
168		    sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX);
169	}
170	return (new_data);
171}
172
173int
174_pthread_setspecific(pthread_key_t key, const void *value)
175{
176	struct pthread	*pthread;
177	int		ret = 0;
178
179	/* Point to the running thread: */
180	pthread = _get_curthread();
181
182	if ((pthread->specific) ||
183	    (pthread->specific = pthread_key_allocate_data())) {
184		if ((unsigned int)key < PTHREAD_KEYS_MAX) {
185			if (_thread_keytable[key].allocated) {
186				if (pthread->specific[key].data == NULL) {
187					if (value != NULL)
188						pthread->specific_data_count++;
189				} else if (value == NULL)
190					pthread->specific_data_count--;
191				*(const void **)&pthread->specific[key].data = value;
192				pthread->specific[key].seqno =
193				    _thread_keytable[key].seqno;
194				ret = 0;
195			} else
196				ret = EINVAL;
197		} else
198			ret = EINVAL;
199	} else
200		ret = ENOMEM;
201	return (ret);
202}
203
204void *
205_pthread_getspecific(pthread_key_t key)
206{
207	struct pthread	*pthread;
208	void		*data;
209
210	/* Point to the running thread: */
211	pthread = _get_curthread();
212
213	/* Check if there is specific data: */
214	if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) {
215		/* Check if this key has been used before: */
216		if (_thread_keytable[key].allocated &&
217		    (pthread->specific[key].seqno == _thread_keytable[key].seqno)) {
218			/* Return the value: */
219			data = pthread->specific[key].data;
220		} else {
221			/*
222			 * This key has not been used before, so return NULL
223			 * instead:
224			 */
225			data = NULL;
226		}
227	} else
228		/* No specific data has been created, so just return NULL: */
229		data = NULL;
230	return (data);
231}
232