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
|
#include <u.h>
#include <libc.h>
#include <draw.h>
#include "libgeometry/geometry.h"
#include "dat.h"
#include "fns.h"
static ulong
get4(uchar *p)
{
return p[0]<<24 | p[1]<<16 | p[2]<<8 | p[3];
}
static void
put4(uchar *p, ulong u)
{
p[0] = u>>24, p[1] = u>>16, p[2] = u>>8, p[3] = u;
}
static int
vpack(uchar *p, int n, char *fmt, va_list a)
{
uchar *p0 = p, *e = p+n;
ulong k;
FPdbleword d;
Point2 P;
for(;;){
switch(*fmt++){
case '\0':
return p - p0;
case 'd':
d.x = va_arg(a, double);
if(p+8 > e)
goto err;
put4(p, d.hi), p += 4;
put4(p, d.lo), p += 4;
break;
case 'P':
P = va_arg(a, Point2);
if(p+3*8 > e)
goto err;
pack(p, n, "ddd", P.x, P.y, P.w), p += 3*8;
break;
case 'k':
k = va_arg(a, ulong);
if(p+4 > e)
goto err;
put4(p, k), p += 4;
break;
}
}
err:
return -1;
}
static int
vunpack(uchar *p, int n, char *fmt, va_list a)
{
uchar *p0 = p, *e = p+n;
ulong k;
FPdbleword d;
Point2 P;
for(;;){
switch(*fmt++){
case '\0':
return p - p0;
case 'd':
if(p+8 > e)
goto err;
d.hi = get4(p), p += 4;
d.lo = get4(p), p += 4;
*va_arg(a, double*) = d.x;
break;
case 'P':
if(p+3*8 > e)
goto err;
unpack(p, n, "ddd", &P.x, &P.y, &P.w), p += 3*8;
*va_arg(a, Point2*) = P;
break;
case 'k':
if(p+4 > e)
goto err;
k = get4(p), p += 4;
*va_arg(a, ulong*) = k;
break;
}
}
err:
return -1;
}
int
pack(uchar *p, int n, char *fmt, ...)
{
va_list a;
va_start(a, fmt);
n = vpack(p, n, fmt, a);
va_end(a);
return n;
}
int
unpack(uchar *p, int n, char *fmt, ...)
{
va_list a;
va_start(a, fmt);
n = vunpack(p, n, fmt, a);
va_end(a);
return n;
}
|
