1 | /* Thread package specific definitions of stream lock type. NPTL version. |
2 | Copyright (C) 2000-2017 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #ifndef _STDIO_LOCK_H |
20 | #define _STDIO_LOCK_H 1 |
21 | |
22 | #include <libc-lock.h> |
23 | #include <lowlevellock.h> |
24 | |
25 | |
26 | /* The locking here is very inexpensive, even for inlining. */ |
27 | #define _IO_lock_inexpensive 1 |
28 | |
29 | typedef struct { int lock; int cnt; void *owner; } _IO_lock_t; |
30 | |
31 | #define _IO_lock_initializer { LLL_LOCK_INITIALIZER, 0, NULL } |
32 | |
33 | #define _IO_lock_init(_name) \ |
34 | ((void) ((_name) = (_IO_lock_t) _IO_lock_initializer)) |
35 | |
36 | #define _IO_lock_fini(_name) \ |
37 | ((void) 0) |
38 | |
39 | #define _IO_lock_lock(_name) \ |
40 | do { \ |
41 | void *__self = THREAD_SELF; \ |
42 | if ((_name).owner != __self) \ |
43 | { \ |
44 | lll_lock ((_name).lock, LLL_PRIVATE); \ |
45 | (_name).owner = __self; \ |
46 | } \ |
47 | ++(_name).cnt; \ |
48 | } while (0) |
49 | |
50 | #define _IO_lock_trylock(_name) \ |
51 | ({ \ |
52 | int __result = 0; \ |
53 | void *__self = THREAD_SELF; \ |
54 | if ((_name).owner != __self) \ |
55 | { \ |
56 | if (lll_trylock ((_name).lock) == 0) \ |
57 | { \ |
58 | (_name).owner = __self; \ |
59 | (_name).cnt = 1; \ |
60 | } \ |
61 | else \ |
62 | __result = EBUSY; \ |
63 | } \ |
64 | else \ |
65 | ++(_name).cnt; \ |
66 | __result; \ |
67 | }) |
68 | |
69 | #define _IO_lock_unlock(_name) \ |
70 | do { \ |
71 | if (--(_name).cnt == 0) \ |
72 | { \ |
73 | (_name).owner = NULL; \ |
74 | lll_unlock ((_name).lock, LLL_PRIVATE); \ |
75 | } \ |
76 | } while (0) |
77 | |
78 | |
79 | |
80 | #define _IO_cleanup_region_start(_fct, _fp) \ |
81 | __libc_cleanup_region_start (((_fp)->_flags & _IO_USER_LOCK) == 0, _fct, _fp) |
82 | #define _IO_cleanup_region_start_noarg(_fct) \ |
83 | __libc_cleanup_region_start (1, _fct, NULL) |
84 | #define _IO_cleanup_region_end(_doit) \ |
85 | __libc_cleanup_region_end (_doit) |
86 | |
87 | #if defined _LIBC && IS_IN (libc) |
88 | |
89 | # ifdef __EXCEPTIONS |
90 | # define _IO_acquire_lock(_fp) \ |
91 | do { \ |
92 | _IO_FILE *_IO_acquire_lock_file \ |
93 | __attribute__((cleanup (_IO_acquire_lock_fct))) \ |
94 | = (_fp); \ |
95 | _IO_flockfile (_IO_acquire_lock_file); |
96 | # define _IO_acquire_lock_clear_flags2(_fp) \ |
97 | do { \ |
98 | _IO_FILE *_IO_acquire_lock_file \ |
99 | __attribute__((cleanup (_IO_acquire_lock_clear_flags2_fct))) \ |
100 | = (_fp); \ |
101 | _IO_flockfile (_IO_acquire_lock_file); |
102 | # else |
103 | # define _IO_acquire_lock(_fp) _IO_acquire_lock_needs_exceptions_enabled |
104 | # define _IO_acquire_lock_clear_flags2(_fp) _IO_acquire_lock (_fp) |
105 | # endif |
106 | # define _IO_release_lock(_fp) ; } while (0) |
107 | |
108 | #endif |
109 | |
110 | #endif /* stdio-lock.h */ |
111 | |