1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2005, David Xu <davidxu@freebsd.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice unmodified, this list of conditions, and the following
12 *    disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32#include "namespace.h"
33#include <pthread.h>
34#include "un-namespace.h"
35
36#include "thr_private.h"
37
38__weak_reference(_thr_cancel, pthread_cancel);
39__weak_reference(_thr_cancel, _pthread_cancel);
40__weak_reference(_thr_setcancelstate, pthread_setcancelstate);
41__weak_reference(_thr_setcancelstate, _pthread_setcancelstate);
42__weak_reference(_thr_setcanceltype, pthread_setcanceltype);
43__weak_reference(_thr_setcanceltype, _pthread_setcanceltype);
44__weak_reference(_Tthr_testcancel, pthread_testcancel);
45__weak_reference(_Tthr_testcancel, _pthread_testcancel);
46__weak_reference(_Tthr_cancel_enter, _pthread_cancel_enter);
47__weak_reference(_Tthr_cancel_leave, _pthread_cancel_leave);
48
49static inline void
50testcancel(struct pthread *curthread)
51{
52	if (__predict_false(SHOULD_CANCEL(curthread) &&
53	    !THR_IN_CRITICAL(curthread)))
54		_pthread_exit(PTHREAD_CANCELED);
55}
56
57void
58_thr_testcancel(struct pthread *curthread)
59{
60	testcancel(curthread);
61}
62
63int
64_thr_cancel(pthread_t pthread)
65{
66	struct pthread *curthread = _get_curthread();
67	int ret;
68
69	/*
70	 * POSIX says _pthread_cancel should be async cancellation safe.
71	 * _thr_find_thread and THR_THREAD_UNLOCK will enter and leave critical
72	 * region automatically.
73	 */
74	if ((ret = _thr_find_thread(curthread, pthread, 1)) == 0) {
75		if (!pthread->cancel_pending) {
76			pthread->cancel_pending = 1;
77			if (pthread->state != PS_DEAD)
78				_thr_send_sig(pthread, SIGCANCEL);
79		}
80		THR_THREAD_UNLOCK(curthread, pthread);
81	}
82	return (ret);
83}
84
85int
86_thr_setcancelstate(int state, int *oldstate)
87{
88	struct pthread *curthread = _get_curthread();
89	int oldval;
90
91	oldval = curthread->cancel_enable;
92	switch (state) {
93	case PTHREAD_CANCEL_DISABLE:
94		curthread->cancel_enable = 0;
95		break;
96	case PTHREAD_CANCEL_ENABLE:
97		curthread->cancel_enable = 1;
98		if (curthread->cancel_async)
99			testcancel(curthread);
100		break;
101	default:
102		return (EINVAL);
103	}
104
105	if (oldstate) {
106		*oldstate = oldval ? PTHREAD_CANCEL_ENABLE :
107			PTHREAD_CANCEL_DISABLE;
108	}
109	return (0);
110}
111
112int
113_thr_setcanceltype(int type, int *oldtype)
114{
115	struct pthread	*curthread = _get_curthread();
116	int oldval;
117
118	oldval = curthread->cancel_async;
119	switch (type) {
120	case PTHREAD_CANCEL_ASYNCHRONOUS:
121		curthread->cancel_async = 1;
122		testcancel(curthread);
123		break;
124	case PTHREAD_CANCEL_DEFERRED:
125		curthread->cancel_async = 0;
126		break;
127	default:
128		return (EINVAL);
129	}
130
131	if (oldtype) {
132		*oldtype = oldval ? PTHREAD_CANCEL_ASYNCHRONOUS :
133		 	PTHREAD_CANCEL_DEFERRED;
134	}
135	return (0);
136}
137
138void
139_Tthr_testcancel(void)
140{
141	struct pthread *curthread;
142
143	_thr_check_init();
144	curthread = _get_curthread();
145	testcancel(curthread);
146}
147
148void
149_thr_cancel_enter(struct pthread *curthread)
150{
151	curthread->cancel_point = 1;
152	testcancel(curthread);
153}
154
155void
156_thr_cancel_enter2(struct pthread *curthread, int maycancel)
157{
158	curthread->cancel_point = 1;
159	if (__predict_false(SHOULD_CANCEL(curthread) &&
160	    !THR_IN_CRITICAL(curthread))) {
161		if (!maycancel)
162			thr_wake(curthread->tid);
163		else
164			_pthread_exit(PTHREAD_CANCELED);
165	}
166}
167
168void
169_thr_cancel_leave(struct pthread *curthread, int maycancel)
170{
171	curthread->cancel_point = 0;
172	if (__predict_false(SHOULD_CANCEL(curthread) &&
173	    !THR_IN_CRITICAL(curthread) && maycancel))
174		_pthread_exit(PTHREAD_CANCELED);
175}
176
177void
178_Tthr_cancel_enter(int maycancel)
179{
180	_thr_cancel_enter2(_get_curthread(), maycancel);
181}
182
183void
184_Tthr_cancel_leave(int maycancel)
185{
186	_thr_cancel_leave(_get_curthread(), maycancel);
187}
188