1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
|
/* Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <assert.h>
#include <errno.h>
#include <string.h>
#include "pthreadP.h"
static const struct pthread_mutexattr default_attr =
{
/* Default is a normal mutex, not shared between processes. */
.mutexkind = PTHREAD_MUTEX_NORMAL
};
#ifndef __ASSUME_FUTEX_LOCK_PI
static int tpi_supported;
#endif
int
__pthread_mutex_init (mutex, mutexattr)
pthread_mutex_t *mutex;
const pthread_mutexattr_t *mutexattr;
{
const struct pthread_mutexattr *imutexattr;
assert (sizeof (pthread_mutex_t) <= __SIZEOF_PTHREAD_MUTEX_T);
imutexattr = (const struct pthread_mutexattr *) mutexattr ?: &default_attr;
/* Sanity checks. */
// XXX For now we don't support priority protected mutexes.
switch (__builtin_expect (imutexattr->mutexkind
& PTHREAD_MUTEXATTR_PROTOCOL_MASK,
PTHREAD_PRIO_NONE
<< PTHREAD_MUTEXATTR_PROTOCOL_SHIFT))
{
case PTHREAD_PRIO_NONE << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
break;
case PTHREAD_PRIO_INHERIT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
#ifndef __ASSUME_FUTEX_LOCK_PI
if (__builtin_expect (tpi_supported == 0, 0))
{
int lock = 0;
INTERNAL_SYSCALL_DECL (err);
int ret = INTERNAL_SYSCALL (futex, err, 4, &lock, FUTEX_UNLOCK_PI,
0, 0);
assert (INTERNAL_SYSCALL_ERROR_P (ret, err));
tpi_supported = INTERNAL_SYSCALL_ERRNO (ret, err) == ENOSYS ? -1 : 1;
}
if (__builtin_expect (tpi_supported < 0, 0))
return ENOTSUP;
#endif
break;
default:
return ENOTSUP;
}
/* Clear the whole variable. */
memset (mutex, '\0', __SIZEOF_PTHREAD_MUTEX_T);
/* Copy the values from the attribute. */
mutex->__data.__kind = imutexattr->mutexkind & ~PTHREAD_MUTEXATTR_FLAG_BITS;
if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0)
{
#ifndef __ASSUME_SET_ROBUST_LIST
if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_PSHARED) != 0
&& __set_robust_list_avail < 0)
return ENOTSUP;
#endif
mutex->__data.__kind |= PTHREAD_MUTEX_ROBUST_NORMAL_NP;
}
switch (imutexattr->mutexkind & PTHREAD_MUTEXATTR_PROTOCOL_MASK)
{
case PTHREAD_PRIO_INHERIT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
mutex->__data.__kind |= PTHREAD_MUTEX_PRIO_INHERIT_NP;
break;
case PTHREAD_PRIO_PROTECT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
mutex->__data.__kind |= PTHREAD_MUTEX_PRIO_PROTECT_NP;
if (PTHREAD_MUTEX_PRIO_CEILING_MASK
== PTHREAD_MUTEXATTR_PRIO_CEILING_MASK)
mutex->__data.__kind |= (imutexattr->mutexkind
& PTHREAD_MUTEXATTR_PRIO_CEILING_MASK);
else
mutex->__data.__kind |= ((imutexattr->mutexkind
& PTHREAD_MUTEXATTR_PRIO_CEILING_MASK)
>> PTHREAD_MUTEXATTR_PRIO_CEILING_SHIFT)
<< PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
break;
default:
break;
}
/* Default values: mutex not used yet. */
// mutex->__count = 0; already done by memset
// mutex->__owner = 0; already done by memset
// mutex->__nusers = 0; already done by memset
// mutex->__spins = 0; already done by memset
// mutex->__next = NULL; already done by memset
return 0;
}
strong_alias (__pthread_mutex_init, pthread_mutex_init)
INTDEF(__pthread_mutex_init)
|
