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
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
|
/* libc-internal interface for mutex locks. Mach cthreads version.
Copyright (C) 1996-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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, see
<https://www.gnu.org/licenses/>. */
#ifndef _LIBC_LOCK_H
#define _LIBC_LOCK_H 1
#ifdef _LIBC
#include <tls.h>
#include <lowlevellock.h>
typedef unsigned int __libc_lock_t;
typedef struct
{
__libc_lock_t lock;
int cnt;
void *owner;
} __libc_lock_recursive_t;
typedef __libc_lock_recursive_t __rtld_lock_recursive_t;
extern char __libc_lock_self0[0];
#define __libc_lock_owner_self() \
(__LIBC_NO_TLS () ? (void *)&__libc_lock_self0 : THREAD_SELF)
#else
typedef struct __libc_lock_opaque__ __libc_lock_t;
typedef struct __libc_lock_recursive_opaque__ __libc_lock_recursive_t;
#endif
/* Define a lock variable NAME with storage class CLASS. The lock must be
initialized with __libc_lock_init before it can be used (or define it
with __libc_lock_define_initialized, below). Use `extern' for CLASS to
declare a lock defined in another module. In public structure
definitions you must use a pointer to the lock structure (i.e., NAME
begins with a `*'), because its storage size will not be known outside
of libc. */
#define __libc_lock_define(CLASS,NAME) \
CLASS __libc_lock_t NAME;
/* Define an initialized lock variable NAME with storage class CLASS. */
#define _LIBC_LOCK_INITIALIZER LLL_LOCK_INITIALIZER
#define __libc_lock_define_initialized(CLASS,NAME) \
CLASS __libc_lock_t NAME = LLL_LOCK_INITIALIZER;
/* Initialize the named lock variable, leaving it in a consistent, unlocked
state. */
#define __libc_lock_init(NAME) (NAME) = LLL_LOCK_INITIALIZER
/* Finalize the named lock variable, which must be locked. It cannot be
used again until __libc_lock_init is called again on it. This must be
called on a lock variable before the containing storage is reused. */
#define __libc_lock_fini __libc_lock_unlock
#define __libc_lock_fini_recursive __libc_lock_unlock_recursive
#define __rtld_lock_fini_recursive __rtld_lock_unlock_recursive
/* Lock the named lock variable. */
#define __libc_lock_lock(NAME) \
({ lll_lock ((NAME), LLL_PRIVATE); 0; })
/* Lock the named lock variable. */
#define __libc_lock_trylock(NAME) lll_trylock (NAME)
/* Unlock the named lock variable. */
#define __libc_lock_unlock(NAME) \
({ lll_unlock ((NAME), LLL_PRIVATE); 0; })
#define __libc_lock_define_recursive(CLASS,NAME) \
CLASS __libc_lock_recursive_t NAME;
#define _LIBC_LOCK_RECURSIVE_INITIALIZER { LLL_LOCK_INITIALIZER, 0, 0 }
#define __libc_lock_define_initialized_recursive(CLASS,NAME) \
CLASS __libc_lock_recursive_t NAME = _LIBC_LOCK_RECURSIVE_INITIALIZER;
#define __rtld_lock_define_recursive(CLASS,NAME) \
__libc_lock_define_recursive (CLASS, NAME)
#define _RTLD_LOCK_RECURSIVE_INITIALIZER \
_LIBC_LOCK_RECURSIVE_INITIALIZER
#define __rtld_lock_define_initialized_recursive(CLASS,NAME) \
__libc_lock_define_initialized_recursive (CLASS, NAME)
#define __libc_lock_init_recursive(NAME) \
({ \
(NAME) = (__libc_lock_recursive_t)_LIBC_LOCK_RECURSIVE_INITIALIZER; \
0; \
})
#define __libc_lock_trylock_recursive(NAME) \
({ \
__libc_lock_recursive_t *const __lock = &(NAME); \
void *__self = __libc_lock_owner_self (); \
int __r = 0; \
if (__self == __lock->owner) \
++__lock->cnt; \
else if ((__r = lll_trylock (__lock->lock)) == 0) \
__lock->owner = __self, __lock->cnt = 1; \
__r; \
})
#define __libc_lock_lock_recursive(NAME) \
({ \
__libc_lock_recursive_t *const __lock = &(NAME); \
void *__self = __libc_lock_owner_self (); \
if (__self != __lock->owner) \
{ \
lll_lock (__lock->lock, 0); \
__lock->owner = __self; \
} \
++__lock->cnt; \
(void)0; \
})
#define __libc_lock_unlock_recursive(NAME) \
({ \
__libc_lock_recursive_t *const __lock = &(NAME); \
if (--__lock->cnt == 0) \
{ \
__lock->owner = 0; \
lll_unlock (__lock->lock, 0); \
} \
})
#define __rtld_lock_initialize(NAME) \
(void) ((NAME) = (__rtld_lock_recursive_t) _RTLD_LOCK_RECURSIVE_INITIALIZER)
#define __rtld_lock_trylock_recursive(NAME) \
__libc_lock_trylock_recursive (NAME)
#define __rtld_lock_lock_recursive(NAME) \
__libc_lock_lock_recursive(NAME)
#define __rtld_lock_unlock_recursive(NAME) \
__libc_lock_unlock_recursive (NAME)
/* XXX for now */
#define __libc_rwlock_define __libc_lock_define
#define __libc_rwlock_define_initialized __libc_lock_define_initialized
#define __libc_rwlock_init __libc_lock_init
#define __libc_rwlock_fini __libc_lock_fini
#define __libc_rwlock_rdlock __libc_lock_lock
#define __libc_rwlock_wrlock __libc_lock_lock
#define __libc_rwlock_tryrdlock __libc_lock_trylock
#define __libc_rwlock_trywrlock __libc_lock_trylock
#define __libc_rwlock_unlock __libc_lock_unlock
struct __libc_cleanup_frame
{
void (*__fct) (void *);
void *__argp;
int __doit;
};
__extern_inline void
__libc_cleanup_fct (struct __libc_cleanup_frame *framep)
{
if (framep->__doit)
framep->__fct (framep->__argp);
}
/* Start a critical region with a cleanup function */
#define __libc_cleanup_region_start(DOIT, FCT, ARG) \
do \
{ \
struct __libc_cleanup_frame __cleanup \
__attribute__ ((__cleanup__ (__libc_cleanup_fct))) = \
{ .__fct = (FCT), .__argp = (ARG), .__doit = (DOIT) };
/* This one closes the brace above. */
#define __libc_cleanup_region_end(DOIT) \
__cleanup.__doit = (DOIT); \
} \
while (0)
#define __libc_cleanup_end(DOIT) __cleanup.__doit = (DOIT);
#define __libc_cleanup_push(fct, arg) __libc_cleanup_region_start (1, fct, arg)
#define __libc_cleanup_pop(execute) __libc_cleanup_region_end (execute)
/* Use mutexes as once control variables. */
struct __libc_once
{
__libc_lock_t lock;
int done;
};
#define __libc_once_define(CLASS,NAME) \
CLASS struct __libc_once NAME = { _LIBC_LOCK_INITIALIZER, 0 }
/* Call handler iff the first call. */
#define __libc_once(ONCE_CONTROL, INIT_FUNCTION) \
do { \
__libc_lock_lock (ONCE_CONTROL.lock); \
if (!ONCE_CONTROL.done) \
(INIT_FUNCTION) (); \
ONCE_CONTROL.done = 1; \
__libc_lock_unlock (ONCE_CONTROL.lock); \
} while (0)
/* Get once control variable. */
#define __libc_once_get(ONCE_CONTROL) ((ONCE_CONTROL).done != 0)
#ifdef _LIBC
/* We need portable names for some functions. E.g., when they are
used as argument to __libc_cleanup_region_start. */
#define __libc_mutex_unlock __libc_lock_unlock
/* Hide the definitions which are only supposed to be used inside libc in
a separate file. This file is not present in the installation! */
# include <libc-lockP.h>
#endif
#endif /* libc-lock.h */
|
