This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
SDL_syscond.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
/*
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
*/
#include "SDL_config.h"
24
25
26
27
28
29
30
31
32
33
34
/*
* GNU pth conditions variables
*
* Patrice Mandin
*/
#include <pth.h>
#include "SDL_thread.h"
#include "SDL_sysmutex_c.h"
35
36
struct SDL_cond
{
37
pth_cond_t condpth_p;
40
/* Create a condition variable */
42
SDL_CreateCond(void)
44
45
SDL_cond *cond;
46
cond = (SDL_cond *) SDL_malloc(sizeof(SDL_cond));
48
49
50
if (pth_cond_init(&(cond->condpth_p)) < 0) {
SDL_SetError("pthread_cond_init() failed");
SDL_free(cond);
51
52
53
cond = NULL;
}
} else {
54
SDL_OutOfMemory();
55
56
}
return (cond);
57
58
59
}
/* Destroy a condition variable */
61
SDL_DestroyCond(SDL_cond * cond)
64
SDL_free(cond);
66
67
68
}
/* Restart one of the threads that are waiting on the condition variable */
70
SDL_CondSignal(SDL_cond * cond)
72
73
74
int retval;
if (!cond) {
75
SDL_SetError("Passed a NULL condition variable");
76
77
78
79
return -1;
}
retval = 0;
80
81
if (pth_cond_notify(&(cond->condpth_p), FALSE) != 0) {
SDL_SetError("pth_cond_notify() failed");
82
83
84
retval = -1;
}
return retval;
85
86
87
}
/* Restart all threads that are waiting on the condition variable */
89
SDL_CondBroadcast(SDL_cond * cond)
91
92
93
int retval;
if (!cond) {
94
SDL_SetError("Passed a NULL condition variable");
95
96
97
98
return -1;
}
retval = 0;
99
100
if (pth_cond_notify(&(cond->condpth_p), TRUE) != 0) {
SDL_SetError("pth_cond_notify() failed");
101
102
103
retval = -1;
}
return retval;
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
}
/* Wait on the condition variable for at most 'ms' milliseconds.
The mutex must be locked before entering this function!
The mutex is unlocked during the wait, and locked again after the wait.
Typical use:
Thread A:
SDL_LockMutex(lock);
while ( ! condition ) {
SDL_CondWait(cond);
}
SDL_UnlockMutex(lock);
Thread B:
SDL_LockMutex(lock);
...
condition = true;
...
SDL_UnlockMutex(lock);
*/
127
SDL_CondWaitTimeout(SDL_cond * cond, SDL_mutex * mutex, Uint32 ms)
129
130
131
int retval;
pth_event_t ev;
int sec;
134
SDL_SetError("Passed a NULL condition variable");
135
136
return -1;
}
140
sec = ms / 1000;
141
142
ev = pth_event(PTH_EVENT_TIME,
pth_timeout(sec, (ms - sec * 1000) * 1000));
144
145
if (pth_cond_await(&(cond->condpth_p), &(mutex->mutexpth_p), ev) != 0) {
SDL_SetError("pth_cond_await() failed");
146
147
retval = -1;
}
149
pth_event_free(ev, PTH_FREE_ALL);
151
return retval;
152
153
154
}
/* Wait on the condition variable forever */
156
SDL_CondWait(SDL_cond * cond, SDL_mutex * mutex)
158
159
160
int retval;
if (!cond) {
161
SDL_SetError("Passed a NULL condition variable");
162
163
164
165
return -1;
}
retval = 0;
166
167
if (pth_cond_await(&(cond->condpth_p), &(mutex->mutexpth_p), NULL) != 0) {
SDL_SetError("pth_cond_await() failed");
168
169
170
retval = -1;
}
return retval;
172
173
/* vi: set ts=4 sw=4 expandtab: */