Optimization makes scanner five times faster

This commit is contained in:
Tnze
2021-06-02 13:35:07 +08:00
parent dd1b8fd9c9
commit d678e9b45a
4 changed files with 141 additions and 136 deletions

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@ -1,4 +1,5 @@
# Go-MC
![Version](https://img.shields.io/badge/Minecraft-1.16.5-blue.svg)
![Protocol](https://img.shields.io/badge/Protocol-754-blue.svg)
[![Go Reference](https://pkg.go.dev/badge/github.com/Tnze/go-mc.svg)](https://pkg.go.dev/github.com/Tnze/go-mc)
@ -12,18 +13,20 @@ There's some library in Go support you to create your Minecraft client or server
- [x] Chat Message (Support Json or old `§`)
- [x] NBT (Based on reflection)
- [ ] SNBT -> NBT
- [x] Yggdrasil
- [x] Realms Server
- [x] RCON protocol (Server & Client)
- [x] Saves decoding & encoding
- [x] Minecraft network protocol
- [x] Robot player framework
- [x] Robot framework
> 由于仍在开发中部分API在未来版本中可能会变动
> `1.13.2` version is at [gomcbot](https://github.com/Tnze/gomcbot).
## Getting start
After you install golang:
To get the latest version: `go get github.com/Tnze/go-mc@master`
To get old versions (e.g. 1.14.3): `go get github.com/Tnze/go-mc@v1.14.3`
@ -33,11 +36,14 @@ First, you might have a try of the simple examples. It's a good start.
### Run Examples
- Run `go run github.com/Tnze/go-mc/cmd/mcping localhost` to ping and list the localhost mc server.
- Run `go run github.com/Tnze/go-mc/cmd/daze` to join the local server at *localhost:25565* as Steve on the offline mode.
- Run `go run github.com/Tnze/go-mc/cmd/daze` to join the local server at *localhost:25565* as Steve on the offline
mode.
### Basic Usage
One of the most useful functions of this lib is that it implements the network communication protocol of minecraft. It allows you to construct, send, receive, and parse network packets. All of them are encapsulated in `go-mc/net` and `go-mc/net/packet`.
One of the most useful functions of this lib is that it implements the network communication protocol of minecraft. It
allows you to construct, send, receive, and parse network packets. All of them are encapsulated in `go-mc/net`
and `go-mc/net/packet`.
这个库最核心的便是实现了Minecraft底层的网络通信协议可以用与构造、发送、接收和解读MC数据包。这是靠 `go-mc/net``go-mc/net/packet`这两个包实现的。
@ -46,7 +52,8 @@ import "github.com/Tnze/go-mc/net"
import pk "github.com/Tnze/go-mc/net/packet"
```
It's very easy to create a packet. For example, after any client connected the server, it sends a [Handshake Packet](https://wiki.vg/Protocol#Handshake). You can create this package with the following code:
It's very easy to create a packet. For example, after any client connected the server, it sends
a [Handshake Packet](https://wiki.vg/Protocol#Handshake). You can create this package with the following code:
构造一个数据包很简单,例如客户端连接时会发送一个[握手包](https://wiki.vg/Protocol#Handshake),你就可以用下面这段代码来生成这个包:
@ -60,7 +67,8 @@ p := pk.Marshal(
)
```
Then you can send it to server using `conn.WritePacket(p)`. The `conn` is a `net.Conn` which is returned by `net.Dial()`. And don't forget to handle the error.^_^
Then you can send it to server using `conn.WritePacket(p)`. The `conn` is a `net.Conn` which is returned by `net.Dial()`
. And don't forget to handle the error.^_^
然后就可以调用`conn.WritePacket(p)`来发送这个p了其中`conn`是连接对象。发数据包的时候记得不要忘记处理错误噢!
@ -91,7 +99,8 @@ Sometimes you are handling packet like this:
| World Count | VarInt | Size of the following array. |
| World Names | Array of Identifier | Identifiers for all worlds on the server. |
That is, the first field is an integer type and the second field is an array (a `[]string` in this case). The integer represents the length of array.
That is, the first field is an integer type and the second field is an array (a `[]string` in this case). The integer
represents the length of array.
Traditionally, you can use the following method to read such a field:
@ -113,7 +122,8 @@ for i := 0; i < int(WorldCount); i++ {
But this is tediously long an not compatible with `p.Scan()` method.
In the latest version, two new types is added: `pk.Ary` and `pk.Opt`. Dedicated to handling "Array of ...." and "Optional ...." fields.
In the latest version, two new types is added: `pk.Ary` and `pk.Opt`. Dedicated to handling "Array of ...." and "
Optional ...." fields.
```go
var WorldCount pk.VarInt
@ -123,15 +133,17 @@ if err := p.Scan(&WorldCount, pk.Ary{&WorldCount, &WorldNames}); err != nil {
}
```
---
As the `go-mc/net` package implements the minecraft network protocol, there is no update between the versions at this level. So net package actually supports any version. It's just that the ID and content of the package are different between different versions.
As the `go-mc/net` package implements the minecraft network protocol, there is no update between the versions at this
level. So net package actually supports any version. It's just that the ID and content of the package are different
between different versions.
由于`go-mc/net`实现的是MC底层的网络协议而这个协议在MC更新时其实并不会有改动MC更新时其实只是包的ID和内容的定义发生了变化所以net包本身是跨版本的。
Originally it's all right to write a bot with only `go-mc/net` package, but considering that the process of handshake, login and encryption is not difficult but complicated, I have implemented it in `go-mc/bot` package, which is **not cross-versions**. You may use it directly or as a reference for your own implementation.
Originally it's all right to write a bot with only `go-mc/net` package, but considering that the process of handshake,
login and encryption is not difficult but complicated, I have implemented it in `go-mc/bot` package, which is **not
cross-versions**. You may use it directly or as a reference for your own implementation.
理论上讲,只用`go-mc/net`包实现一个bot是完全可行的但是为了节省大家从头去理解MC握手、登录、加密等协议的过程`go-mc/bot`中我已经把这些都实现了,只不过它不是跨版本的。你可以直接使用,或者作为自己实现的参考。

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@ -242,7 +242,7 @@ func (d *decodeState) readIndex() int {
// scanNext processes the byte at d.data[d.off].
func (d *decodeState) scanNext() {
if d.off < len(d.data) {
d.opcode = d.scan.step(d.data[d.off])
d.opcode = d.scan.step(&d.scan, d.data[d.off])
d.off++
} else {
//d.opcode = d.scan.eof()
@ -255,7 +255,7 @@ func (d *decodeState) scanNext() {
func (d *decodeState) scanWhile(op int) {
s, data, i := &d.scan, d.data, d.off
for i < len(data) {
newOp := s.step(data[i])
newOp := s.step(s, data[i])
i++
if newOp != op {
d.opcode = newOp

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@ -2,7 +2,6 @@ package nbt
import (
"errors"
"sync"
)
const (
@ -34,7 +33,7 @@ const (
const maxNestingDepth = 10000
type scanner struct {
step func(c byte) int
step func(s *scanner, c byte) int
parseState []int
err error
endTop bool
@ -43,30 +42,10 @@ type scanner struct {
// reset prepares the scanner for use.
// It must be called before calling s.step.
func (s *scanner) reset() {
s.step = s.stateBeginValue
s.step = stateBeginValue
s.parseState = s.parseState[0:0]
}
var scannerPool = sync.Pool{
New: func() interface{} {
return &scanner{}
},
}
func newScanner() *scanner {
scan := scannerPool.Get().(*scanner)
// scan.reset by design doesn't set bytes to zero
//scan.bytes = 0
scan.reset()
return scan
}
func freeScanner(scan *scanner) {
// Avoid hanging on to too much memory in extreme cases.
if len(scan.parseState) > 1024 {
scan.parseState = nil
}
scannerPool.Put(scan)
s.err = nil
s.endTop = false
}
// pushParseState pushes a new parse state p onto the parse stack.
@ -85,10 +64,10 @@ func (s *scanner) popParseState() {
n := len(s.parseState) - 1
s.parseState = s.parseState[:n]
if n == 0 {
s.step = s.stateEndTop
s.step = stateEndTop
s.endTop = true
} else {
s.step = s.stateEndValue
s.step = stateEndValue
}
}
@ -101,7 +80,7 @@ func (s *scanner) eof() int {
if s.endTop {
return scanEnd
}
s.step(' ')
s.step(s, ' ')
if s.endTop {
return scanEnd
}
@ -114,7 +93,7 @@ func (s *scanner) eof() int {
// stateEndTop is the state after finishing the top-level value,
// such as after reading `{}` or `[1,2,3]`.
// Only space characters should be seen now.
func (s *scanner) stateEndTop(c byte) int {
func stateEndTop(s *scanner, c byte) int {
if !isSpace(c) {
// Complain about non-space byte on next call.
s.error(c, "after top-level value")
@ -122,195 +101,195 @@ func (s *scanner) stateEndTop(c byte) int {
return scanEnd
}
func (s *scanner) stateBeginValue(c byte) int {
func stateBeginValue(s *scanner, c byte) int {
if isSpace(c) {
s.step = s.stateBeginValue
s.step = stateBeginValue
return scanSkipSpace
}
switch c {
case '{': // beginning of TAG_Compound
s.step = s.stateCompoundOrEmpty
s.step = stateCompoundOrEmpty
return s.pushParseState(c, parseCompoundName, scanBeginCompound)
case '[': // beginning of TAG_List
s.step = s.stateListOrArray
s.step = stateListOrArray
return s.pushParseState(c, parseListValue, scanBeginList)
case '"', '\'': // beginning of TAG_String
return s.stateBeginString(c)
return stateBeginString(s, c)
case '-': // beginning of negative number
s.step = s.stateNeg
s.step = stateNeg
return scanBeginLiteral
default:
if isNumber(c) {
s.stateNum0(c)
stateNum0(s, c)
return scanBeginLiteral
}
if isAllowedInUnquotedString(c) {
return s.stateBeginString(c)
return stateBeginString(s, c)
}
}
return s.error(c, "looking for beginning of value")
}
func (s *scanner) stateCompoundOrEmpty(c byte) int {
func stateCompoundOrEmpty(s *scanner, c byte) int {
if isSpace(c) {
return scanSkipSpace
}
if c == '}' {
n := len(s.parseState)
s.parseState[n-1] = parseCompoundValue
return s.stateEndValue(c)
return stateEndValue(s, c)
}
return s.stateBeginString(c)
return stateBeginString(s, c)
}
func (s *scanner) stateBeginString(c byte) int {
func stateBeginString(s *scanner, c byte) int {
if isSpace(c) {
return scanSkipSpace
}
switch c {
case '\'':
s.step = s.stateInSingleQuotedString
s.step = stateInSingleQuotedString
return scanBeginLiteral
case '"':
s.step = s.stateInDoubleQuotedString
s.step = stateInDoubleQuotedString
return scanBeginLiteral
default:
if isAllowedInUnquotedString(c) {
s.step = s.stateInUnquotedString
s.step = stateInUnquotedString
return scanBeginLiteral
}
}
return s.error(c, "looking for beginning of string")
}
func (s *scanner) stateInSingleQuotedString(c byte) int {
func stateInSingleQuotedString(s *scanner, c byte) int {
if c == '\\' {
s.step = s.stateInSingleQuotedStringEsc
s.step = stateInSingleQuotedStringEsc
return scanContinue
}
if c == '\'' {
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
}
return scanContinue
}
func (s *scanner) stateInSingleQuotedStringEsc(c byte) int {
func stateInSingleQuotedStringEsc(s *scanner, c byte) int {
switch c {
case 'b', 'f', 'n', 'r', 't', '\\', '/', '\'':
s.step = s.stateInSingleQuotedString
s.step = stateInSingleQuotedString
return scanContinue
}
return s.error(c, "in string escape code")
}
func (s *scanner) stateInDoubleQuotedString(c byte) int {
func stateInDoubleQuotedString(s *scanner, c byte) int {
if c == '\\' {
s.step = s.stateInDqStringEsc
s.step = stateInDqStringEsc
return scanContinue
}
if c == '"' {
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
}
return scanContinue
}
func (s *scanner) stateInDqStringEsc(c byte) int {
func stateInDqStringEsc(s *scanner, c byte) int {
switch c {
case 'b', 'f', 'n', 'r', 't', '\\', '/', '"':
s.step = s.stateInDoubleQuotedString
s.step = stateInDoubleQuotedString
return scanContinue
}
return s.error(c, "in string escape code")
}
func (s *scanner) stateInUnquotedString(c byte) int {
func stateInUnquotedString(s *scanner, c byte) int {
if isAllowedInUnquotedString(c) {
return scanContinue
}
return s.stateEndValue(c)
return stateEndValue(s, c)
}
func (s *scanner) stateListOrArray(c byte) int {
func stateListOrArray(s *scanner, c byte) int {
if isSpace(c) {
return scanSkipSpace
}
switch c {
case 'B', 'I', 'L':
s.step = s.stateListOrArrayT
s.step = stateListOrArrayT
return scanBeginLiteral
case ']':
return s.stateEndValue(c)
return stateEndValue(s, c)
default:
return s.stateBeginValue(c)
return stateBeginValue(s, c)
}
}
func (s *scanner) stateListOrArrayT(c byte) int {
func stateListOrArrayT(s *scanner, c byte) int {
if c == ';' {
s.step = s.stateArrayT
s.step = stateArrayT
return scanListType
}
return s.stateInUnquotedString(c)
return stateInUnquotedString(s, c)
}
func (s *scanner) stateArrayT(c byte) int {
func stateArrayT(s *scanner, c byte) int {
if c == ']' { // empty array
return scanEndValue
}
return s.stateBeginValue(c)
return stateBeginValue(s, c)
}
func (s *scanner) stateNeg(c byte) int {
func stateNeg(s *scanner, c byte) int {
if isNumber(c) {
s.step = s.stateNum0
s.step = stateNum0
return scanBeginLiteral
}
if isAllowedInUnquotedString(c) {
s.step = s.stateInUnquotedString
s.step = stateInUnquotedString
return scanBeginLiteral
}
return s.error(c, "not a number after '-'")
}
func (s *scanner) stateNum0(c byte) int {
func stateNum0(s *scanner, c byte) int {
if isNumber(c) {
s.step = s.stateNum1
s.step = stateNum1
return scanContinue
}
if isAllowedInUnquotedString(c) {
s.step = s.stateInUnquotedString
s.step = stateInUnquotedString
return scanContinue
}
return s.stateEndNumValue(c)
return stateEndNumValue(s, c)
}
func (s *scanner) stateNum1(c byte) int {
func stateNum1(s *scanner, c byte) int {
if isNumber(c) {
s.step = s.stateNum1
s.step = stateNum1
return scanContinue
}
if c == '.' {
s.step = s.stateNumDot
s.step = stateNumDot
return scanContinue
}
if isAllowedInUnquotedString(c) {
s.step = s.stateInUnquotedString
s.step = stateInUnquotedString
return scanContinue
}
return s.stateEndNumValue(c)
return stateEndNumValue(s, c)
}
// stateDot is the state after reading the integer and decimal point in a number,
// such as after reading `1.`.
func (s *scanner) stateNumDot(c byte) int {
func stateNumDot(s *scanner, c byte) int {
if isNumber(c) {
s.step = s.stateNumDot0
s.step = stateNumDot0
return scanContinue
}
if isAllowedInUnquotedString(c) {
s.step = s.stateInUnquotedString
s.step = stateInUnquotedString
return scanContinue
}
return s.error(c, "after decimal point in numeric literal")
@ -318,54 +297,54 @@ func (s *scanner) stateNumDot(c byte) int {
// stateNumDot0 is the state after reading the integer, decimal point, and subsequent
// digits of a number, such as after reading `3.14`.
func (s *scanner) stateNumDot0(c byte) int {
func stateNumDot0(s *scanner, c byte) int {
if isNumber(c) {
s.step = s.stateNumDot0
s.step = stateNumDot0
return scanContinue
}
if isAllowedInUnquotedString(c) {
s.step = s.stateInUnquotedString
s.step = stateInUnquotedString
return scanContinue
}
return s.stateEndNumDotValue(c)
return stateEndNumDotValue(s, c)
}
func (s *scanner) stateEndNumValue(c byte) int {
func stateEndNumValue(s *scanner, c byte) int {
switch c {
case 'b', 'B': // TAG_Byte
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
case 's', 'S': // TAG_Short
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
case 'l', 'L': // TAG_Long
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
case 'f', 'F', 'd', 'D':
return s.stateEndNumDotValue(c)
return stateEndNumDotValue(s, c)
}
return s.stateEndValue(c)
return stateEndValue(s, c)
}
func (s *scanner) stateEndNumDotValue(c byte) int {
func stateEndNumDotValue(s *scanner, c byte) int {
switch c {
case 'f', 'F': // TAG_Float
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
case 'd', 'D': // TAG_Double
s.step = s.stateEndValue
s.step = stateEndValue
return scanContinue
}
return s.stateEndValue(c)
return stateEndValue(s, c)
}
func (s *scanner) stateEndValue(c byte) int {
func stateEndValue(s *scanner, c byte) int {
n := len(s.parseState)
if n == 0 {
// Completed top-level before the current byte.
s.step = s.stateEndTop
s.step = stateEndTop
s.endTop = true
return s.stateEndTop(c)
return stateEndTop(s, c)
}
if isSpace(c) {
return scanSkipSpace
@ -376,7 +355,7 @@ func (s *scanner) stateEndValue(c byte) int {
case parseCompoundName:
if c == ':' {
s.parseState[n-1] = parseCompoundValue
s.step = s.stateBeginValue
s.step = stateBeginValue
return scanCompoundTagName
}
return s.error(c, "after compound tag name")
@ -384,7 +363,7 @@ func (s *scanner) stateEndValue(c byte) int {
switch c {
case ',':
s.parseState[n-1] = parseCompoundName
s.step = s.stateBeginString
s.step = stateBeginString
return scanCompoundValue
case '}':
s.popParseState()
@ -394,7 +373,7 @@ func (s *scanner) stateEndValue(c byte) int {
case parseListValue:
switch c {
case ',':
s.step = s.stateBeginValue
s.step = stateBeginValue
return scanListValue
case ']':
s.popParseState()
@ -406,14 +385,14 @@ func (s *scanner) stateEndValue(c byte) int {
}
func (s *scanner) error(c byte, context string) int {
s.step = s.stateError
s.step = stateError
s.err = errors.New(context)
return scanError
}
// stateError is the state after reaching a syntax error,
// such as after reading `[1}` or `5.1.2`.
func (s *scanner) stateError(c byte) int {
func stateError(s *scanner, c byte) int {
return scanError
}

View File

@ -9,8 +9,8 @@ func TestSNBT_checkScanCode(t *testing.T) {
//t.SkipNow()
var s scanner
s.reset()
for _, c := range []byte(`[{},{a:1b},{}]`) {
t.Logf("[%c] - %d", c, s.step(c))
for _, c := range []byte(`[I;123,345]`) {
t.Logf("[%c] - %d", c, s.step(&s, c))
}
t.Logf("[%c] - %d", ' ', s.eof())
}
@ -26,7 +26,7 @@ func TestSNBT_number(t *testing.T) {
scan := func(str string) bool {
s.reset()
for _, c := range []byte(str) {
res := s.step(c)
res := s.step(&s, c)
if res == scanError {
return false
}
@ -53,7 +53,7 @@ func TestSNBT_compound(t *testing.T) {
for _, str := range goods {
s.reset()
for i, c := range []byte(str) {
res := s.step(c)
res := s.step(&s, c)
if res == scanError {
t.Errorf("scan valid data %q error: %v at [%d]", str[:i], s.err, i)
break
@ -73,7 +73,7 @@ func TestSNBT_list(t *testing.T) {
scan := func(str string) bool {
s.reset()
for _, c := range []byte(str) {
res := s.step(c)
res := s.step(&s, c)
if res == scanError {
return false
}
@ -86,3 +86,17 @@ func TestSNBT_list(t *testing.T) {
}
}
}
func BenchmarkSNBT_bigTest(b *testing.B) {
var s scanner
for i := 0; i < b.N; i++ {
s.reset()
for _, c := range []byte(bigTest) {
res := s.step(&s, c)
if res == scanError {
b.Errorf("scan valid data %q error: %v at [%d]", bigTest[:i], s.err, i)
break
}
}
}
}