-
Notifications
You must be signed in to change notification settings - Fork 1
/
packer.go
283 lines (276 loc) · 6.61 KB
/
packer.go
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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
package protocol
import (
"encoding/binary"
"time"
"unsafe"
)
type buffer struct {
buf map[uint16][]byte
len uint16
max uint16
ts uint64
}
type stream struct {
buf map[uint16]*buffer
len uint16
cursor *uint16
}
type Packer struct {
blockBuf map[[10]byte]*buffer
streamBuf map[string]*stream
readFrame func() *Frame
}
func NewPacker(readFrame func() *Frame) *Packer {
particle := &Packer{
blockBuf: make(map[[10]byte]*buffer),
streamBuf: make(map[string]*stream),
readFrame: readFrame,
}
return particle
}
func (p *Packer) Assemble() (label string, data [][]byte) {
// 0x04 is it a stream frame
// 0x02 is it separated as pieces
// 0x01 0 means it is the last piece, 1 means the other pieces
for {
frame := p.readFrame()
if frame.Payload[0]&0x04 > 0 {
s, ok := p.streamBuf[frame.Label]
if !ok {
s = &stream{buf: make(map[uint16]*buffer)}
p.streamBuf[frame.Label] = s
}
i := binary.BigEndian.Uint16(frame.Payload[1:])
if frame.Payload[0]&0x02 > 0 {
j := binary.BigEndian.Uint16(frame.Payload[3:])
t := binary.BigEndian.Uint64(frame.Payload[5:])
b, ok := s.buf[i]
if !ok {
b = &buffer{
buf: make(map[uint16][]byte),
ts: t,
}
s.buf[i] = b
} else if t > b.ts {
b.buf = make(map[uint16][]byte)
b.len = 0
b.max = 0
b.ts = t
}
b.buf[j] = frame.Payload[13:]
b.len++
if frame.Payload[0]&0x01 == 0 {
b.max = j + 1
}
if b.len == b.max {
if s.cursor == nil {
delete(s.buf, i)
payload := make([]byte, 0, 1024)
for k := uint16(0); k < b.max; k++ {
payload = append(payload, b.buf[k]...)
}
label = frame.Label
data = append(data, payload)
i++
s.cursor = &i
frame.Recycle()
return
}
s.len++
goto NEXT
}
} else if s.cursor == nil {
label = frame.Label
data = append(data, frame.Payload[11:])
i++
s.cursor = &i
frame.Recycle()
return
} else {
s.buf[i] = &buffer{
buf: map[uint16][]byte{0: frame.Payload[11:]},
len: 1,
max: 1,
ts: binary.BigEndian.Uint64(frame.Payload[3:]),
}
s.len++
goto NEXT
}
goto CONTINUE
NEXT:
if b, ok := s.buf[*s.cursor]; ok && b.len == b.max {
delete(s.buf, *s.cursor)
payload := make([]byte, 0, 1024)
for k := uint16(0); k < b.max; k++ {
payload = append(payload, b.buf[k]...)
}
data = append(data, payload)
s.len--
*s.cursor++
goto NEXT
} else if data != nil {
label = frame.Label
frame.Recycle()
return
} else if s.len > 20 {
var min *uint16
for i, b := range s.buf {
if b.len == b.max {
if min == nil {
tmp := i
min = &tmp
} else if b.ts < s.buf[*min].ts {
*min = i
}
}
}
s.cursor = min
goto NEXT
}
} else if frame.Payload[0]&0x02 > 0 {
var key [10]byte
copy(key[:], frame.Payload[1:])
b, ok := p.blockBuf[key]
if !ok {
b = &buffer{
buf: make(map[uint16][]byte),
ts: binary.BigEndian.Uint64(key[:8]),
}
p.blockBuf[key] = b
}
i := binary.BigEndian.Uint16(frame.Payload[11:])
b.buf[i] = frame.Payload[13:]
b.len++
if frame.Payload[0]&0x01 == 0 {
b.max = i + 1
}
if b.len == b.max {
delete(p.blockBuf, key)
payload := make([]byte, 0, 1024)
for k := uint16(0); k < b.max; k++ {
payload = append(payload, b.buf[k]...)
}
label = frame.Label
data = append(data, payload)
frame.Recycle()
return
}
// TODO check ts and remove
} else {
label = frame.Label
data = append(data, frame.Payload[1:])
frame.Recycle()
return
}
CONTINUE:
frame.Recycle()
}
}
func (p *Packer) Pack(label string, data any) <-chan *Frame {
switch data := data.(type) {
case []byte:
if dlen := len(data); dlen > 0 {
if dlen < 4095 {
frame := NewFrame()
frame.Act = ActMulticast
frame.Label = label
frame.Payload = make([]byte, 1+dlen)
copy(frame.Payload[1:], data)
frames := make(chan *Frame, 1)
frames <- frame
close(frames)
return frames
} else {
var i uint16
var s uint64
now := uint64(time.Now().UnixNano())
rand := uint16(uintptr(unsafe.Pointer(&data)))
frames := make(chan *Frame, dlen/4082+1)
for ; dlen > 4082; dlen = dlen - 4082 {
e := s + 4082
frame := NewFrame()
frame.Act = ActMulticast
frame.Label = label
frame.Payload = make([]byte, 4095)
frame.Payload[0] = 0x03
binary.BigEndian.PutUint64(frame.Payload[1:], now)
binary.BigEndian.PutUint16(frame.Payload[9:], rand)
binary.BigEndian.PutUint16(frame.Payload[11:], i)
copy(frame.Payload[13:], data[s:e])
frames <- frame
s = e
i++
}
frame := NewFrame()
frame.Act = ActMulticast
frame.Label = label
frame.Payload = make([]byte, 13+dlen)
frame.Payload[0] = 0x02
binary.BigEndian.PutUint64(frame.Payload[1:], now)
binary.BigEndian.PutUint16(frame.Payload[9:], rand)
binary.BigEndian.PutUint16(frame.Payload[11:], i)
copy(frame.Payload[13:], data[s:])
frames <- frame
close(frames)
return frames
}
}
case chan []byte:
frames := make(chan *Frame)
go func() {
var i uint16
for b := range data {
dlen := len(b)
if dlen == 0 {
continue
}
now := uint64(time.Now().UnixNano())
if dlen <= 4084 {
frame := NewFrame()
frame.Act = ActMulticast
frame.Label = label
frame.Payload = make([]byte, 11+dlen)
frame.Payload[0] = 0x04
binary.BigEndian.PutUint16(frame.Payload[1:], i)
binary.BigEndian.PutUint64(frame.Payload[3:], now)
copy(frame.Payload[11:], b)
frames <- frame
} else {
var j uint16
var s uint64
for ; dlen > 4082; dlen = dlen - 4082 {
e := s + 4082
frame := NewFrame()
frame.Act = ActMulticast
frame.Label = label
frame.Payload = make([]byte, 4095)
frame.Payload[0] = 0x07
binary.BigEndian.PutUint16(frame.Payload[1:], i)
binary.BigEndian.PutUint16(frame.Payload[3:], j)
binary.BigEndian.PutUint64(frame.Payload[5:], now)
copy(frame.Payload[13:], b[s:e])
frames <- frame
s = e
j++
}
frame := NewFrame()
frame.Act = ActMulticast
frame.Label = label
frame.Payload = make([]byte, 13+dlen)
frame.Payload[0] = 0x06
binary.BigEndian.PutUint16(frame.Payload[1:], i)
binary.BigEndian.PutUint16(frame.Payload[3:], j)
binary.BigEndian.PutUint64(frame.Payload[5:], now)
copy(frame.Payload[13:], b[s:])
frames <- frame
}
i++
}
close(frames)
}()
return frames
}
frames := make(chan *Frame)
close(frames)
return frames
}