当SQL语句太长的时候，sniffer会异常

[chao]

例如，捕捉到一个有1000个参数的Insert的SQL语句的时候出错：

, @p906, @p907, @p908, @p909, @p910, @p911, @p912, @p913, @p914, @p915, @p916, @p917, @p918, @p919, @p920, @p921, @p922, @p923, @p924, @p925, @p926, @p927, @p928, @p929, @p930, @p931, @p932, @p933, @p934, @p935, @p936, @p937, @p938, @p939, @p940, @p941, @p942, @p943, @p944, @p945, @p946, @p947, @p948, @p949, @p950, @p951, @p952, @p953, @p954, @p955, @p956, @p957, @p958, @p959, @p960, @p961, @p962, @p963, @p964, @p965, @p966, @p967, @p968, @p969, @p970, @p971, @p972, @p973, @p974, @p975, @p976, @p977, @p978, @p979, @p980, @p981, @p982, @p983, @p984, @p985, @p986, @p987, @p988, @p989, @p990, @p991, @p992, @p993, @p994, @p995, @p996, @p997, @p998, @p999;
Drop stm id[4];

panic: runtime error: index out of range

goroutine 1411 [running]:
encoding/binary.binary.littleEndian.Uint32(...)
	/usr/local/go/src/encoding/binary/binary.go:63
github.com/40t/go-sniffer/plugSrc/mysql/build.LengthBinary(0xc4206d6c01, 0x32, 0x5ff, 0x9b47d8, 0xc420044c00)
	/root/go/src/github.com/40t/go-sniffer/plugSrc/mysql/build/util.go:41 +0xc2
github.com/40t/go-sniffer/plugSrc/mysql/build.(*stream).resolveServerPacket(0xc4200571c0, 0xc4206d6c00, 0x33, 0x600, 0x1)
	/root/go/src/github.com/40t/go-sniffer/plugSrc/mysql/build/entry.go:230 +0x2fc
github.com/40t/go-sniffer/plugSrc/mysql/build.(*stream).resolve(0xc4200571c0)
	/root/go/src/github.com/40t/go-sniffer/plugSrc/mysql/build/entry.go:194 +0xc0
created by github.com/40t/go-sniffer/plugSrc/mysql/build.(*Mysql).ResolveStream
	/root/go/src/github.com/40t/go-sniffer/plugSrc/mysql/build/entry.go:71 +0x3b8

[cctse]

查询语句，数据并没多少

[40t]

代码 pull 一下，麻烦check一下

[hhkens]

改了下这个文件 暂时解决
cat /root/go-sniffer-master/plugSrc/mysql/build/util.go 
package build

import (
        "bytes"
        "encoding/binary"
        "io"
        "time"
)

func GetNowStr(isClient bool) string {
        var msg string
        msg += time.Now().Format("2006-01-02 15:04:05")
        if isClient {
                msg += "| cli -> ser |"
        }else{
                msg += "| ser -> cli |"
        }
        return msg
}

func ReadStringFromByte(b []byte) (string,int) {

        var l int
        l = bytes.IndexByte(b, 0x00)
        if l == -1 {
                l = len(b)
        }
        return string(b[0:l]), l
}

func LengthBinary(b []byte) (uint32, int) {

        var first = int(b[0])
        if first > 0 && first <= 250 {
                return uint32(first), 1
        }
        if first == 251 {
                return 0,1
        }
        if first == 252 {
                return binary.LittleEndian.Uint32(b[1:2]),1
        }
        if first == 253 {
                return binary.LittleEndian.Uint32(b[1:4]),3
        }
        if first == 254 {
                return binary.LittleEndian.Uint32(b[1:9]),8
        }
        return 0,0
}

func LengthEncodedInt(input []byte) (num uint64, isNull bool, n int) {
    if len(input) == 0 {
        // 输入为空，返回默认值，表示无效
        return 0, false, 0
    }

    switch input[0] {
    case 0xfb:
        n = 1
        isNull = true
        return
    case 0xfc:
        if len(input) < 3 {
            return 0, false, 0 // 数据不足，返回默认值
        }
        num = uint64(input[1]) | uint64(input[2])<<8
        n = 3
        return
    case 0xfd:
        if len(input) < 4 {
            return 0, false, 0 // 数据不足，返回默认值
        }
        num = uint64(input[1]) | uint64(input[2])<<8 | uint64(input[3])<<16
        n = 4
        return
    case 0xfe:
        if len(input) < 9 {
            return 0, false, 0 // 数据不足，返回默认值
        }
        num = uint64(input[1]) | uint64(input[2])<<8 | uint64(input[3])<<16 |
            uint64(input[4])<<24 | uint64(input[5])<<32 | uint64(input[6])<<40 |
            uint64(input[7])<<48 | uint64(input[8])<<56
        n = 9
        return
    }

    num = uint64(input[0])
    n = 1
    return
}


func LengthEncodedString(b []byte) ([]byte, bool, int, error) {

        num, isNull, n := LengthEncodedInt(b)
        if num < 1 {
                return nil, isNull, n, nil
        }

        n += int(num)

        if len(b) >= n {
                return b[n-int(num) : n], false, n, nil
        }
        return nil, false, n, io.EOF

}