使用 dlv 调试go 程序

Posted 2020-12-31 baizx

目录

• 使用 dlv 调试smartraiden
  • 一 正常启动 smartraiden
  • 二 dlv 调试
    • 三 dlv attach

使用 dlv 调试smartraiden

by 白振轩

• 使用 dlv 调试smartraiden
  • 一 正常启动 smartraiden
  • 二 dlv 调试
    • 三 dlv attach
      • goroutines -s 查看所有 goroutine 的栈
      • 解决问题

对于程序运行过程中碰到的莫名其妙的问题,比如不明原因的阻塞,命令行 dlv 调试可能比 ide 调试效果更好

一 正常启动 smartraiden

./smartraiden --datadir=.smartraiden --api-address=0.0.0.0:5001 --listen-address=127.0.0.1:40001  --address="0x292650fee408320D888e06ed89D938294Ea42f99" --keystore-path ~/privnet3/keystore --registry-contract-address 0xf450955d87F23DF5DFc7297ed6DdDF4fb896Eff2  --password-file 123      --verbosity 5    --debug  --conditionquit "{"QuitEvent":"EventSendRevealSecretBeforex"}" --debugcrash  --eth-rpc-endpoint ws://127.0.0.1:8546

二 dlv 调试

1. 出了问题,但是没有崩溃,直接 attach 即可
2. 出了问题,但是崩溃了,可以提前设置断点

三 dlv attach

attach 成功以后,程序会停止运行

goroutines -s 查看所有 goroutine 的栈

解决问题

1. 如果觉得某个 goroutine 有问题
   goroutine 108 就可以切换到这个 goroutine, 进行调试
2. bt 查看堆栈

(dlv) goroutine 108
Switched from 0 to 108 (thread 4644478)
(dlv) bt
0  0x000000000402f66a in runtime.gopark
  at /usr/local/go/src/runtime/proc.go:292
1  0x000000000403f150 in runtime.selectgo
  at /usr/local/go/src/runtime/select.go:392
2  0x0000000004608329 in github.com/SmartMeshFoundation/SmartRaiden/blockchain.(*Events).startListenEvent.func1
  at /Volumes/dev/smdev2/src/github.com/SmartMeshFoundation/SmartRaiden/blockchain/events.go:275
3  0x000000000405c3d1 in runtime.goexit
  at /usr/local/go/src/runtime/asm_amd64.s:2361

1. 在栈之间移动up/down

up
up

会显示当前可以控制的栈
Frame 2: /Volumes/dev/smdev2/src/github.com/SmartMeshFoundation/SmartRaiden/blockchain/events.go:275 (PC: 4608329) 270: go func(name string) { 271: ch := be.LogChannelMap[name] 272: sub := be.Subscribes[name] 273: defer rpanic.PanicRecover(fmt.Sprintf("startListenEvent %s", name)) 274: for { => 275: select { 276: case l, ok := <-ch: 277: if !ok { 278: //channel closed 279: return 280: } (dlv)

1. 查看局部变量
   locals 可以显示目前所有的局部变量,也可以通过p 来打印具体的局部变量和全局变量.

(dlv) p ch
chan github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log {
    qcount: 0,
    dataqsiz: 10,
    buf: *[10]struct github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log [
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc420335500),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc4203355a8),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc420335650),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc4203356f8),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc4203357a0),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc420335848),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc4203358f0),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc420335998),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc420335a40),
        (*github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log)(0xc420335ae8),
    ],
    elemsize: 168,
    closed: 0,
    elemtype: *runtime._type {
        size: 168,
        ptrdata: 56,
        hash: 3390961113,
        tflag: tflagUncommon|tflagExtraStar|tflagNamed,
        align: 8,
        fieldalign: 8,
        kind: 25,
        alg: *(*runtime.typeAlg)(0x5218c40),
        gcdata: *72,
        str: 56993,
        ptrToThis: 1205856,},
    sendx: 0,
    recvx: 0,
    recvq: waitq<github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log> {
        first: *(*sudog<github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log>)(0xc4304ae4e0),
        last: *(*sudog<github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log>)(0xc4304ae4e0),},
    sendq: waitq<github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log> {
        first: *sudog<github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log> nil,
        last: *sudog<github.com/SmartMeshFoundation/SmartRaiden/vendor/github.com/ethereum/go-ethereum/core/types.Log> nil,},
    lock: runtime.mutex {key: 0},}
(dlv)

可以看到 ch 这个 chann 目前没有任何数据,所以阻塞.

1. 也可以查看全局变量.也就是包级别的变量.

(dlv) p "github.com/SmartMeshFoundation/SmartRaiden/params".MobileMode
false
(dlv) p "github.com/SmartMeshFoundation/SmartRaiden/params".ChainID
*math/big.Int {
    neg: false,
    abs: math/big.nat len: 1, cap: 5, [8888],}
(dlv)