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 <u.h>
#include <libc.h>
#include <draw.h>
#include <thread.h>
#include <cursor.h>
#include <mouse.h>
#include <keyboard.h>
#include <frame.h>
#include <fcall.h>
#include <plumb.h>
#include "dat.h"
#include "fns.h"
static Channel* ctimer; /* chan(Timer*)[100] */
static Timer *timer;
static
uint
msec(void)
{
return nsec()/1000000;
}
void
timerstop(Timer *t)
{
t->next = timer;
timer = t;
}
void
timercancel(Timer *t)
{
t->cancel = TRUE;
}
static
void
timerproc(void *v)
{
int i, nt, na, dt, del;
Timer **t, *x;
uint old, new;
USED(v);
threadsetname("timerproc");
rfork(RFFDG);
t = nil;
na = 0;
nt = 0;
old = msec();
for(;;){
threadsleep(1); /* will sleep minimum incr */
new = msec();
dt = new-old;
old = new;
if(dt < 0) /* timer wrapped; go around, losing a tick */
continue;
for(i=0; i<nt; i++){
x = t[i];
x->dt -= dt;
del = FALSE;
if(x->cancel){
timerstop(x);
del = TRUE;
}else if(x->dt <= 0){
/*
* avoid possible deadlock if client is
* now sending on ctimer
*/
if(nbsendul(x->c, 0) > 0)
del = TRUE;
}
if(del){
memmove(&t[i], &t[i+1], (nt-i-1)*sizeof t[0]);
--nt;
--i;
}
}
if(nt == 0){
x = recvp(ctimer);
gotit:
if(nt == na){
na += 10;
t = realloc(t, na*sizeof(Timer*));
if(t == nil)
error("timer realloc failed");
}
t[nt++] = x;
old = msec();
}
if(nbrecv(ctimer, &x) > 0)
goto gotit;
}
}
void
timerinit(void)
{
ctimer = chancreate(sizeof(Timer*), 100);
threadcreate(timerproc, nil, STACK);
}
Timer*
timerstart(int dt)
{
Timer *t;
t = timer;
if(t)
timer = timer->next;
else{
t = emalloc(sizeof(Timer));
t->c = chancreate(sizeof(int), 0);
}
t->next = nil;
t->dt = dt;
t->cancel = FALSE;
sendp(ctimer, t);
return t;
}
|