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
|
#include "MessageLoop.h"
#include <assert.h>
lifo_t nu::MessageLoop::message_cache = {0,};
lifo_t nu::MessageLoop::cache_bases= {0,};
#define MESSAAGE_CACHE_SEED 64
typedef uint8_t message_data_t[64]; // ensure all messages are this size
nu::MessageLoop::MessageLoop()
{
mpscq_init(&message_queue);
message_notification = CreateEvent(0, FALSE, FALSE, 0);
}
nu::MessageLoop::~MessageLoop()
{
CloseHandle(message_notification);
}
void nu::MessageLoop::RefillCache()
{
message_data_t *cache_seed = (message_data_t *)_aligned_malloc(MESSAAGE_CACHE_SEED*sizeof(message_data_t), 64);
if (cache_seed)
{
int i=MESSAAGE_CACHE_SEED;
while (--i)
{
lifo_push(&message_cache, (queue_node_t *)&cache_seed[i]);
}
lifo_push(&cache_bases, (queue_node_t *)cache_seed);
}
else
{
Sleep(0); // yield and hope that someone else pops something off soon
}
}
nu::message_node_t *nu::MessageLoop::AllocateMessage()
{
message_node_t *apc = 0;
do
{
apc = (message_node_t *)lifo_pop(&message_cache);
if (!apc)
RefillCache();
} while (!apc);
return apc;
}
void nu::MessageLoop::PostMessage(nu::message_node_t *message)
{
if (mpscq_push(&message_queue, message) == 0)
SetEvent(message_notification);
}
void nu::MessageLoop::FreeMessage(nu::message_node_t *message)
{
lifo_push(&message_cache, message);
}
nu::message_node_t *nu::MessageLoop::GetMessage()
{
message_node_t *message = PeekMessage();
if (message)
{
return message;
}
while (WaitForSingleObject(message_notification, INFINITE) == WAIT_OBJECT_0)
{
message = PeekMessage();
if (message)
{
return message;
}
}
return 0;
}
nu::message_node_t *nu::MessageLoop::PeekMessage()
{
for (;;) // loop because we need to handle 'busy' from the queue
{
message_node_t *message = (message_node_t *)mpscq_pop(&message_queue);
if (message == (message_node_t *)1) /* special return value that indicates a busy list */
{
// benski> although it's tempting to return 0 here, doing so will mess up the Event logic
Sleep(0); // yield so that the thread that got pre-empted during push can finish
}
else
{
if (message)
{
return message;
}
else
{
return 0;
}
}
}
}
nu::message_node_t *nu::MessageLoop::PeekMessage(unsigned int milliseconds)
{
message_node_t *message = PeekMessage();
if (message)
return message;
if (WaitForSingleObject(message_notification, milliseconds) == WAIT_OBJECT_0)
{
message = PeekMessage();
if (message)
return message;
}
return 0;
}
|
