1/* Thread package specific definitions of stream lock type.  NPTL version.
2   Copyright (C) 2000, 2001, 2002, 2003, 2007 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, write to the Free
17   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18   02111-1307 USA.  */
19
20#ifndef _BITS_STDIO_LOCK_H
21#define _BITS_STDIO_LOCK_H 1
22
23#include <bits/libc-lock.h>
24#include <lowlevellock.h>
25
26
27/* The locking here is very inexpensive, even for inlining.  */
28#define _IO_lock_inexpensive	1
29
30typedef struct { int lock; int cnt; void *owner; } _IO_lock_t;
31
32#define _IO_lock_initializer { LLL_LOCK_INITIALIZER, 0, NULL }
33
34#define _IO_lock_init(_name) \
35  ((_name) = (_IO_lock_t) _IO_lock_initializer , 0)
36
37#define _IO_lock_fini(_name) \
38  ((void) 0)
39
40#define _IO_lock_lock(_name) \
41  do {									      \
42    void *__self = THREAD_SELF;						      \
43    if ((_name).owner != __self)					      \
44      {									      \
45	lll_lock ((_name).lock, LLL_PRIVATE);				      \
46        (_name).owner = __self;						      \
47      }									      \
48    ++(_name).cnt;							      \
49  } while (0)
50
51#define _IO_lock_trylock(_name) \
52  ({									      \
53    int __result = 0;							      \
54    void *__self = THREAD_SELF;						      \
55    if ((_name).owner != __self)					      \
56      {									      \
57        if (lll_trylock ((_name).lock) == 0)				      \
58          {								      \
59            (_name).owner = __self;					      \
60            (_name).cnt = 1;						      \
61          }								      \
62        else								      \
63          __result = EBUSY;						      \
64      }									      \
65    else								      \
66      ++(_name).cnt;							      \
67    __result;								      \
68  })
69
70#define _IO_lock_unlock(_name) \
71  do {									      \
72    if (--(_name).cnt == 0)						      \
73      {									      \
74        (_name).owner = NULL;						      \
75	lll_unlock ((_name).lock, LLL_PRIVATE);				      \
76      }									      \
77  } while (0)
78
79
80
81#define _IO_cleanup_region_start(_fct, _fp) \
82  __libc_cleanup_region_start (((_fp)->_flags & _IO_USER_LOCK) == 0, _fct, _fp)
83#define _IO_cleanup_region_start_noarg(_fct) \
84  __libc_cleanup_region_start (1, _fct, NULL)
85#define _IO_cleanup_region_end(_doit) \
86  __libc_cleanup_region_end (_doit)
87
88#if defined _LIBC && !defined NOT_IN_libc
89
90# ifdef __EXCEPTIONS
91#  define _IO_acquire_lock(_fp) \
92  do {									      \
93    _IO_FILE *_IO_acquire_lock_file					      \
94	__attribute__((cleanup (_IO_acquire_lock_fct)))			      \
95	= (_fp);							      \
96    _IO_flockfile (_IO_acquire_lock_file);
97#  define _IO_acquire_lock_clear_flags2(_fp) \
98  do {									      \
99    _IO_FILE *_IO_acquire_lock_file					      \
100	__attribute__((cleanup (_IO_acquire_lock_clear_flags2_fct)))	      \
101	= (_fp);							      \
102    _IO_flockfile (_IO_acquire_lock_file);
103# else
104#  define _IO_acquire_lock(_fp) _IO_acquire_lock_needs_exceptions_enabled
105#  define _IO_acquire_lock_clear_flags2(_fp) _IO_acquire_lock (_fp)
106# endif
107# define _IO_release_lock(_fp) ; } while (0)
108
109#endif
110
111#endif /* bits/stdio-lock.h */
112