/
SDL_mutex.h
162 lines (123 loc) · 5.57 KB
/
SDL_mutex.h
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
/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2006 Sam Lantinga
This 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.
This 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 this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Sam Lantinga
slouken@libsdl.org
*/
#ifndef _SDL_mutex_h
#define _SDL_mutex_h
/* Functions to provide thread synchronization primitives
These are independent of the other SDL routines.
*/
#include "SDL_stdinc.h"
#include "SDL_error.h"
#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif
/* Synchronization functions which can time out return this value
if they time out.
*/
#define SDL_MUTEX_TIMEDOUT 1
/* This is the timeout value which corresponds to never time out */
#define SDL_MUTEX_MAXWAIT (~(Uint32)0)
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* Mutex functions */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* The SDL mutex structure, defined in SDL_mutex.c */
struct SDL_mutex;
typedef struct SDL_mutex SDL_mutex;
/* Create a mutex, initialized unlocked */
extern DECLSPEC SDL_mutex * SDLCALL SDL_CreateMutex(void);
/* Lock the mutex (Returns 0, or -1 on error) */
#define SDL_LockMutex(m) SDL_mutexP(m)
extern DECLSPEC int SDLCALL SDL_mutexP(SDL_mutex *mutex);
/* Unlock the mutex (Returns 0, or -1 on error)
It is an error to unlock a mutex that has not been locked by
the current thread, and doing so results in undefined behavior.
*/
#define SDL_UnlockMutex(m) SDL_mutexV(m)
extern DECLSPEC int SDLCALL SDL_mutexV(SDL_mutex *mutex);
/* Destroy a mutex */
extern DECLSPEC void SDLCALL SDL_DestroyMutex(SDL_mutex *mutex);
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* Semaphore functions */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* The SDL semaphore structure, defined in SDL_sem.c */
struct SDL_semaphore;
typedef struct SDL_semaphore SDL_sem;
/* Create a semaphore, initialized with value, returns NULL on failure. */
extern DECLSPEC SDL_sem * SDLCALL SDL_CreateSemaphore(Uint32 initial_value);
/* Destroy a semaphore */
extern DECLSPEC void SDLCALL SDL_DestroySemaphore(SDL_sem *sem);
/* This function suspends the calling thread until the semaphore pointed
* to by sem has a positive count. It then atomically decreases the semaphore
* count.
*/
extern DECLSPEC int SDLCALL SDL_SemWait(SDL_sem *sem);
/* Non-blocking variant of SDL_SemWait(), returns 0 if the wait succeeds,
SDL_MUTEX_TIMEDOUT if the wait would block, and -1 on error.
*/
extern DECLSPEC int SDLCALL SDL_SemTryWait(SDL_sem *sem);
/* Variant of SDL_SemWait() with a timeout in milliseconds, returns 0 if
the wait succeeds, SDL_MUTEX_TIMEDOUT if the wait does not succeed in
the allotted time, and -1 on error.
On some platforms this function is implemented by looping with a delay
of 1 ms, and so should be avoided if possible.
*/
extern DECLSPEC int SDLCALL SDL_SemWaitTimeout(SDL_sem *sem, Uint32 ms);
/* Atomically increases the semaphore's count (not blocking), returns 0,
or -1 on error.
*/
extern DECLSPEC int SDLCALL SDL_SemPost(SDL_sem *sem);
/* Returns the current count of the semaphore */
extern DECLSPEC Uint32 SDLCALL SDL_SemValue(SDL_sem *sem);
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* Condition variable functions */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* The SDL condition variable structure, defined in SDL_cond.c */
struct SDL_cond;
typedef struct SDL_cond SDL_cond;
/* Create a condition variable */
extern DECLSPEC SDL_cond * SDLCALL SDL_CreateCond(void);
/* Destroy a condition variable */
extern DECLSPEC void SDLCALL SDL_DestroyCond(SDL_cond *cond);
/* Restart one of the threads that are waiting on the condition variable,
returns 0 or -1 on error.
*/
extern DECLSPEC int SDLCALL SDL_CondSignal(SDL_cond *cond);
/* Restart all threads that are waiting on the condition variable,
returns 0 or -1 on error.
*/
extern DECLSPEC int SDLCALL SDL_CondBroadcast(SDL_cond *cond);
/* Wait on the condition variable, unlocking the provided mutex.
The mutex must be locked before entering this function!
The mutex is re-locked once the condition variable is signaled.
Returns 0 when it is signaled, or -1 on error.
*/
extern DECLSPEC int SDLCALL SDL_CondWait(SDL_cond *cond, SDL_mutex *mut);
/* Waits for at most 'ms' milliseconds, and returns 0 if the condition
variable is signaled, SDL_MUTEX_TIMEDOUT if the condition is not
signaled in the allotted time, and -1 on error.
On some platforms this function is implemented by looping with a delay
of 1 ms, and so should be avoided if possible.
*/
extern DECLSPEC int SDLCALL SDL_CondWaitTimeout(SDL_cond *cond, SDL_mutex *mutex, Uint32 ms);
/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"
#endif /* _SDL_mutex_h */