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
|
/******************************************************
The interface to the operating system
synchronization primitives.
(c) 1995 Innobase Oy
Created 9/6/1995 Heikki Tuuri
*******************************************************/
#ifndef os0sync_h
#define os0sync_h
#include "univ.i"
#ifdef __WIN__
#define os_fast_mutex_t CRITICAL_SECTION
typedef void* os_event_t;
#else
typedef pthread_mutex_t os_fast_mutex_t;
struct os_event_struct {
os_fast_mutex_t os_mutex; /* this mutex protects the next
fields */
ibool is_set; /* this is TRUE if the next mutex is
not reserved */
pthread_cond_t cond_var; /* condition variable is used in
waiting for the event */
};
typedef struct os_event_struct os_event_struct_t;
typedef os_event_struct_t* os_event_t;
#endif
typedef struct os_mutex_struct os_mutex_str_t;
typedef os_mutex_str_t* os_mutex_t;
#define OS_SYNC_INFINITE_TIME ((ulint)(-1))
#define OS_SYNC_TIME_EXCEEDED 1
/*************************************************************
Creates an event semaphore, i.e., a semaphore which may
just have two states: signaled and nonsignaled.
The created event is manual reset: it must be reset
explicitly by calling sync_os_reset_event. */
os_event_t
os_event_create(
/*============*/
/* out: the event handle */
char* name); /* in: the name of the event, if NULL
the event is created without a name */
/*************************************************************
Creates an auto-reset event semaphore, i.e., an event
which is automatically reset when a single thread is
released. */
os_event_t
os_event_create_auto(
/*=================*/
/* out: the event handle */
char* name); /* in: the name of the event, if NULL
the event is created without a name */
/**************************************************************
Sets an event semaphore to the signaled state: lets waiting threads
proceed. */
void
os_event_set(
/*=========*/
os_event_t event); /* in: event to set */
/**************************************************************
Resets an event semaphore to the nonsignaled state. Waiting threads will
stop to wait for the event. */
void
os_event_reset(
/*===========*/
os_event_t event); /* in: event to reset */
/**************************************************************
Frees an event object. */
void
os_event_free(
/*==========*/
os_event_t event); /* in: event to free */
/**************************************************************
Waits for an event object until it is in the signaled state. */
void
os_event_wait(
/*==========*/
os_event_t event); /* in: event to wait */
/**************************************************************
Waits for an event object until it is in the signaled state or
a timeout is exceeded. */
ulint
os_event_wait_time(
/*===============*/
/* out: 0 if success,
OS_SYNC_TIME_EXCEEDED if timeout
was exceeded */
os_event_t event, /* in: event to wait */
ulint time); /* in: timeout in microseconds, or
OS_SYNC_INFINITE_TIME */
/**************************************************************
Waits for any event in an event array. Returns if even a single
one is signaled or becomes signaled. */
ulint
os_event_wait_multiple(
/*===================*/
/* out: index of the event
which was signaled */
ulint n, /* in: number of events in the
array */
os_event_t* event_array); /* in: pointer to an array of event
handles */
/*************************************************************
Creates an operating system mutex semaphore.
Because these are slow, the mutex semaphore of the database
itself (sync_mutex_t) should be used where possible. */
os_mutex_t
os_mutex_create(
/*============*/
/* out: the mutex handle */
char* name); /* in: the name of the mutex, if NULL
the mutex is created without a name */
/**************************************************************
Acquires ownership of a mutex semaphore. */
void
os_mutex_enter(
/*===========*/
os_mutex_t mutex); /* in: mutex to acquire */
/**************************************************************
Releases ownership of a mutex. */
void
os_mutex_exit(
/*==========*/
os_mutex_t mutex); /* in: mutex to release */
/**************************************************************
Frees an mutex object. */
void
os_mutex_free(
/*==========*/
os_mutex_t mutex); /* in: mutex to free */
/**************************************************************
Acquires ownership of a fast mutex. Currently in Windows this is the same
as os_fast_mutex_lock! */
UNIV_INLINE
ulint
os_fast_mutex_trylock(
/*==================*/
/* out: 0 if success, != 0 if
was reserved by another
thread */
os_fast_mutex_t* fast_mutex); /* in: mutex to acquire */
/**************************************************************
Releases ownership of a fast mutex. */
void
os_fast_mutex_unlock(
/*=================*/
os_fast_mutex_t* fast_mutex); /* in: mutex to release */
/*************************************************************
Initializes an operating system fast mutex semaphore. */
void
os_fast_mutex_init(
/*===============*/
os_fast_mutex_t* fast_mutex); /* in: fast mutex */
/**************************************************************
Acquires ownership of a fast mutex. */
void
os_fast_mutex_lock(
/*===============*/
os_fast_mutex_t* fast_mutex); /* in: mutex to acquire */
/**************************************************************
Frees an mutex object. */
void
os_fast_mutex_free(
/*===============*/
os_fast_mutex_t* fast_mutex); /* in: mutex to free */
#ifndef UNIV_NONINL
#include "os0sync.ic"
#endif
#endif
|
