看看我写的DSL（1）-数据包创建
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fineqtbull
2009-11-14
正在用Scala开发一个开源协议测试软件，准备尝试一下DSL的开发，在这里晒晒阶段开发成果。学Scala开发不久，不保证这是DSL的最好设计，仅供大家参考和讨论。
//创建数据包（ICMP Echo Request）
val pingRequest = ^^^("EtherProtocol") {
^^("EtherProtocol") {
^("dstAddress") = AS("11:22:33:44:55:66", MAC_ADDRESS)
^("srcAddress") = AS("22:22:33:44:55:66", MAC_ADDRESS)
^("etherType") = 0x0800
^("payload") {
^("ipv4") {
^("header") {
^("identification") = 1
^("timeToLive") = 255
^("protocol") = 1
^("sourceAddress") = AS("192.168.1.1", IPV4_ADDRESS)
^("destinationAddress") = AS("192.168.1.2", IPV4_ADDRESS)
^("options") {
^(0) {
^("security") {
^("security" ) = 0x789A
}
}
^(1) {
^("lssr") {
^("pointer" ) = 100
}
}
}
}
^("payload") {
^("icmpv4") {
^("echoRequest") {
^("identifier") = 100
^("sequenceNumber") = 1000
^("data") = OS("01020304")
}
}
}
}
}
}
}
//打印
ValueDumper.dump(pingRequest)
执行结果： 0:66 EtherProtocol.EtherProtocol 0:6 dstAddress 11:22:33:44:55:66 6:6 srcAddress 22:22:33:44:55:66 12:2 etherType 2048 IPv4 14:48 payload 14:48 ipv4 Ipv4Protocol.Ipv4Protocol 14:48 Ipv4Protocol.Ipv4Protocol 14:36 header 14:1 0000---- 4 version 0xF0 14:1 ----0000 0 headerLength 0x0F 15:1 typeOfService '00000000'B 16:2 totalLength 0 18:2 identification 1 20:1 0--------------- 0 reserved 0x8000 20:1 -0-------------- false doNotFrag 0x4000 20:1 --0------------- false moreFrags 0x2000 20:2 ---0000000000000 0 fragmentOffset 0x1FFF 22:1 timeToLive 255 23:1 protocol 1 ICMP: Internet Control Message Protocol 24:2 hcs '0000'O 26:4 sourceAddress 192.168.1.1 30:4 destinationAddress 192.168.1.2 34:16 options 34:12 [0] 34:12 security 34:1 optionType 130 35:1 optionLength 0 36:2 security 30874 EFTO 38:2 compartments 0 40:2 handling 0 42:3 tcc 0 45:1 nop 1 46:4 [1] 46:4 lssr 46:1 optionType 131 47:1 optionLength 0 48:1 pointer 100 49:0 routeData 49:1 nop 1 50:12 payload 50:12 icmpv4 Icmpv4Protocol.Icmpv4Protocol 50:12 Icmpv4Protocol.Icmpv4Protocol 50:12 echoRequest 50:1 icmpType 8 51:1 icmpCode 0 52:2 checksum '0000'O 54:2 identifier 100 56:2 sequenceNumber 1000 58:4 data '01020304'O 62:4 fcs '00000000'O |
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night_stalker
2009-11-14
这些 ^ 太奇怪了 …… 还比不上老老实实赋值简洁平白 ……
val pingRequest = new EtherProtocol() {
dstAddress = MAC("11:22:33:44:55:66")
srcAddress = MAC("22:22:33:44:55:66")
etherType = 0x0800
payload = new Ipv4() {
...
}
}
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fineqtbull
2009-11-14
night_stalker 写道 这些 ^ 太奇怪了 …… 还比不上老老实实赋值简洁平白 ……
val pingRequest = new EtherProtocol() {
dstAddress = MAC("11:22:33:44:55:66")
srcAddress = MAC("22:22:33:44:55:66")
etherType = 0x0800
payload = new Ipv4() {
...
}
} ,这种方案我也考虑过，而且在性能上也会好一点，还可以靠编译器来检查字段名称正确与否，不过要另外生成Scala类，所以暂时还不会实现。直接用^("字段名")格式是由于协议格式已经以别的文本形式定义了，所以不用生成Scala类直接用字段名就可以了，觉得会方便一点。下面是Ethernet协议的定义：
module EtherProtocol {
import from BasicTypeAndValues {
type Oct6, UInt16, Oct4, MacAddress
}
import from Ipv4Protocol {
type Ipv4Protocol
}
import from ArpProtocol {
type ArpProtocol
}
import from GlobalEnumSets {
enumset EtherTypes
}
import from Ipv6Protocol {
type Ipv6Protocol
}
type record EtherProtocol {
MacAddress dstAddress,
MacAddress srcAddress,
UInt16 etherType,
EtherPayload payload,
Oct4 fcs optional
} with {
variant Protocol(true); PushEmptyField([DECODE], "etherType")
variant(etherType) SetField([DECODE])
enumref(etherType) EtherTypes
}
type union EtherPayload {
Ipv4Protocol ipv4,
ArpProtocol arp,
Ipv6Protocol ipv6,
octetstring data
} with {
variant CaseRef("-etherType", #UInt16); CaseDefault(data)
variant(ipv4) CaseCond(UInt16 (0x0800))
variant(arp) CaseCond(UInt16 (0x0806))
variant(ipv6) CaseCond(UInt16 (0x86DD))
}
} with {
encode "FPB"
variant ByteOrder(BIG_ENDIAN)
}
PS:本来想用#的，不过#是关键字所以选了^。另外^^^、^^、^分别表示模块、类型、字段。 |
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matt.u
2009-11-17
^^^太不直观了。
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fineqtbull
2009-11-17
matt.u 写道 ^^^太不直观了。
主要是考虑到模块、类型、字段的层次关系，字段用得最多，如果用“field”等字符输入会挺麻烦，所以用了一个符号^。而根据层次关系，由此得来了^^和^^^。上来可能有点怪.... |
