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
|
#include "serialise.hh"
#include "util.hh"
#include <cstring>
namespace nix {
void FdSink::operator () (const unsigned char * data, unsigned int len)
{
writeFull(fd, data, len);
}
void FdSource::operator () (unsigned char * data, unsigned int len)
{
readFull(fd, data, len);
}
void writePadding(unsigned int len, Sink & sink)
{
if (len % 8) {
unsigned char zero[8];
memset(zero, 0, sizeof(zero));
sink(zero, 8 - (len % 8));
}
}
void writeInt(unsigned int n, Sink & sink)
{
unsigned char buf[8];
memset(buf, 0, sizeof(buf));
buf[0] = n & 0xff;
buf[1] = (n >> 8) & 0xff;
buf[2] = (n >> 16) & 0xff;
buf[3] = (n >> 24) & 0xff;
sink(buf, sizeof(buf));
}
void writeLongLong(unsigned long long n, Sink & sink)
{
unsigned char buf[8];
buf[0] = n & 0xff;
buf[1] = (n >> 8) & 0xff;
buf[2] = (n >> 16) & 0xff;
buf[3] = (n >> 24) & 0xff;
buf[4] = (n >> 32) & 0xff;
buf[5] = (n >> 40) & 0xff;
buf[6] = (n >> 48) & 0xff;
buf[7] = (n >> 56) & 0xff;
sink(buf, sizeof(buf));
}
void writeString(const string & s, Sink & sink)
{
unsigned int len = s.length();
writeInt(len, sink);
sink((const unsigned char *) s.c_str(), len);
writePadding(len, sink);
}
void writeStringSet(const StringSet & ss, Sink & sink)
{
writeInt(ss.size(), sink);
for (StringSet::iterator i = ss.begin(); i != ss.end(); ++i)
writeString(*i, sink);
}
void readPadding(unsigned int len, Source & source)
{
if (len % 8) {
unsigned char zero[8];
unsigned int n = 8 - (len % 8);
source(zero, n);
for (unsigned int i = 0; i < n; i++)
if (zero[i]) throw Error("non-zero padding");
}
}
unsigned int readInt(Source & source)
{
unsigned char buf[8];
source(buf, sizeof(buf));
if (buf[4] || buf[5] || buf[6] || buf[7])
throw Error("implementation cannot deal with > 32-bit integers");
return
buf[0] |
(buf[1] << 8) |
(buf[2] << 16) |
(buf[3] << 24);
}
unsigned long long readLongLong(Source & source)
{
unsigned char buf[8];
source(buf, sizeof(buf));
return
((unsigned long long) buf[0]) |
((unsigned long long) buf[1] << 8) |
((unsigned long long) buf[2] << 16) |
((unsigned long long) buf[3] << 24) |
((unsigned long long) buf[4] << 32) |
((unsigned long long) buf[5] << 40) |
((unsigned long long) buf[6] << 48) |
((unsigned long long) buf[7] << 56);
}
string readString(Source & source)
{
unsigned int len = readInt(source);
unsigned char * buf = new unsigned char[len];
AutoDeleteArray<unsigned char> d(buf);
source(buf, len);
readPadding(len, source);
return string((char *) buf, len);
}
StringSet readStringSet(Source & source)
{
unsigned int count = readInt(source);
StringSet ss;
while (count--)
ss.insert(readString(source));
return ss;
}
}
|
