2 * Copyright (c) 1998 John Birrell <jb@cimlogic.com.au>.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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 REGENTS 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
29 * $FreeBSD: src/lib/libc/stdio/_flock_stub.c,v 1.16 2008/04/17 22:17:53 jhb Exp $
33 * POSIX stdio FILE locking functions. These assume that the locking
34 * is only required at FILE structure level, not at file descriptor
39 #include "namespace.h"
42 #include "un-namespace.h"
49 pthread_t curthread
= _pthread_self();
51 if (fp
->_fl_owner
== curthread
)
55 * Make sure this mutex is treated as a private
58 _pthread_mutex_lock(&fp
->_fl_mutex
);
59 fp
->_fl_owner
= curthread
;
65 * This can be overridden by the threads library if it is linked in.
68 _flockfile_debug_stub(FILE *fp
, char *fname __unused
, int lineno __unused
)
74 _ftrylockfile(FILE *fp
)
76 pthread_t curthread
= _pthread_self();
79 if (fp
->_fl_owner
== curthread
)
82 * Make sure this mutex is treated as a private
85 else if (_pthread_mutex_trylock(&fp
->_fl_mutex
) == 0) {
86 fp
->_fl_owner
= curthread
;
95 _funlockfile(FILE *fp
)
97 pthread_t curthread
= _pthread_self();
100 * Check if this file is owned by the current thread:
102 if (fp
->_fl_owner
== curthread
) {
104 * Check if this thread has locked the FILE
107 if (fp
->_fl_count
> 1) {
109 * Decrement the count of the number of
110 * times the running thread has locked this
116 * The running thread will release the
120 fp
->_fl_owner
= NULL
;
121 _pthread_mutex_unlock(&fp
->_fl_mutex
);
127 * Weak symbols for externally visible functions in this file:
129 __weak_reference(_flockfile
, flockfile
);
130 __weak_reference(_flockfile_debug_stub
, _flockfile_debug
);
131 __weak_reference(_ftrylockfile
, ftrylockfile
);
132 __weak_reference(_funlockfile
, funlockfile
);