Go调试工具—— Delve
参考https://github.com/go-delve/delve
安装
首先你必须有等于或高于1.8版本的Go,我的版本是:
userdeMBP:go-learning user$ go version go version go1.11.4 darwin/amd64
我是用的是Mac,所以使用的是OSX安装方法:
然后使用go get 进行安装:
go get -u github.com/go-delve/delve/cmd/dlv
使用这种方法,你将无法使用delve的本机后端,但无论如何您都不需要它:macOS上的本机后端已经知道该操作系统最近出现的问题,并且目前没有进行维护。详情可见https://github.com/go-delve/delve/issues/1112
安装完后查看版本:
userdeMBP:go-learning user$ dlv version Delve Debugger Version: 1.2.0 Build: $Id: 068e...57e34f0f08ce01466 $
使用:
1)首先先使用dlv或dlv --help来查看delve支持的命令:
userdeMBP:go-learning user$ dlv Delve是Go程序的源代码级调试器. Delve通过控制进程的执行、评估变量以及提供线程/ goroutine状态、CPU寄存器状态等信息,使你能够与程序进行交互。 这个工具的目标是为调试Go程序提供一个简单而强大的接口. 使用“--”将标志传递给正在调试的程序,例如: `dlv exec ./hello -- server --config conf/config.toml` Usage: dlv [command] Available Commands: attach 连接到正在运行的流程并开始调试. connect 连接到无头调试服务器. core 检查核心转储. debug 编译并开始调试当前目录下的主包或指定的包. exec 执行预编译的二进制文件,并开始调试会话. help 帮助信息 run 弃用的命令。使用“debug”替代它. test 编译测试二进制文件并开始调试程序. trace 编译并开始跟踪程序. version 打印版本. Flags: --accept-multiclient 允许无头服务器接受多个客户机连接。注意,服务器API不是可重入的,客户端必须协调. --api-version int 无头时选择API版本. (default 1) --backend string 后端选择: default 在macOS上使用lldb,其他地方都是本地的. native 本地后端. lldb 使用lldb-server或debugserver. rr 使用mozilla rr (https://github.com/mozilla/rr). (default "default") 默认使用的是default --build-flags string 生成标志,以传递给编译器. --headless 仅在headless模式下运行调试服务器. --init string 初始化文件,由终端客户端执行. -l, --listen string 调试服务器监听地址. (default "localhost:0") --log 启用调试服务器日志记录. --log-output string 应该产生调试输出的组件的逗号分隔列表,可能的值为: debugger 记录调试器命令 gdbwire 日志连接到gdbserial后端 lldbout 将输出从debugserver/lldb复制到标准输出 debuglineerr 读取.debug_line时日志可恢复错误 rpc 记录所有RPC消息 fncall 日志函数调用协议 minidump 日志minidump加载 使用--log启用日志时,默认为“debugger”. --wd string 用于运行程序的工作目录. (default ".") 使用"dlv [command] --help"获取有关命令的详细信息.
支持的命令太多了,在这里我们主要介绍它的调试命令——debug
2.dlv debug
首先使用dlv debug --help 查看其的帮助信息:
userdeMBP:go-learning user$ dlv debug --help 编译禁用优化的程序,启动并附加到该程序。 默认情况下,没有参数,Delve将编译当前目录中的“main”包,并开始调试它。或者,您可以指定一个包名,Delve将编译该包,并开始一个新的调试会话。 Usage: dlv debug [package] [flags] Flags: --output string 二进制文件的输出路径. (default "debug") Global Flags:和上面的一样,这里省略
举例说明:
首先要进行调试的代码为:
package main import ( "fmt" "time" ) func counting(c chan<- int){ for i := 0; i < 10; i++{ time.Sleep(2 * time.Second) c <- i } close(c) } func main() { msg := "Starting main" fmt.Println(msg) bus := make(chan int) msg = "starting a gofunc" go counting(bus) for count := range bus{ fmt.Println("count : ", count) } }
然后开启调试:
userdeMBP:go-learning user$ dlv debug test.go Type 'help' for list of commands. (dlv)
然后我们可以输入help来查看能够使用的debug命令有哪些:
The following commands are available: args ------------------------ 打印函数参数. break (alias: b) ------------ 设置断点. breakpoints (alias: bp) ----- 输出活动断点的信息. call ------------------------ 恢复进程,注入一个函数调用(还在实验阶段!!) clear ----------------------- 删除断点. clearall -------------------- 删除多个断点. condition (alias: cond) ----- 设置断点条件. config ---------------------- 修改配置参数. continue (alias: c) --------- 运行到断点或程序终止. deferred -------------------- 在延迟调用的上下文中执行命令. disassemble (alias: disass) - 反汇编程序. down ------------------------ 将当前帧向下移动. edit (alias: ed) ------------ 在$DELVE_EDITOR或$EDITOR中打开你所在的位置 exit (alias: quit | q) ------ 退出调试器. frame ----------------------- 设置当前帧,或在不同的帧上执行命令. funcs ----------------------- 打印函数列表. goroutine ------------------- 显示或更改当前goroutine goroutines ------------------ 列举程序goroutines. help (alias: h) ------------- 打印帮助信息. list (alias: ls | l) -------- 显示源代码. locals ---------------------- 打印局部变量. next (alias: n) ------------- 转到下一个源行. on -------------------------- 在命中断点时执行命令. print (alias: p) ------------ 计算一个表达式. regs ------------------------ 打印CPU寄存器的内容. restart (alias: r) ---------- 重启进程. set ------------------------- 更改变量的值. source ---------------------- 执行包含delve命令列表的文件 sources --------------------- 打印源文件列表. stack (alias: bt) ----------- 打印堆栈跟踪信息. step (alias: s) ------------- 单步执行程序. step-instruction (alias: si) 单步执行一条cpu指令. stepout --------------------- 跳出当前函数. thread (alias: tr) ---------- 切换到指定的线程. threads --------------------- 打印每个跟踪线程的信息. trace (alias: t) ------------ 设置跟踪点. types ----------------------- 打印类型列表 up -------------------------- 向上移动当前帧. vars ------------------------ 打印包变量. whatis ---------------------- 打印表达式的类型. 在命令前键入help来获得命令的完整文档,如help goroutine
2)首先开始进行调试,这里先什么都不做直接输入continue,即c,运行到断点或程序终止
(dlv) c Starting main count : 0 count : 1 count : 2 count : 3 count : 4 count : 5 count : 6 count : 7 count : 8 count : 9 Process 1324 has exited with status 0
可见这个代码跑了起来
3)restart(缩写r)重启进程
(dlv) b main.main Process 1324 has exited with status 0
上面进行添加断点的操作,但是并没有返回想要的信息
这是因为我们之前已经将程序运行结束了,这时候不能直接添加断点信息
所以要先调用restart来将进程重启
4)break(即b)添加断点
现在我们可以为其添加断点了
(dlv) b main.main //在main函数处添加断点 Breakpoint 1 set at 0x10b123b for main.main() ./test.go:16 (dlv) b main.counting //在counting函数处添加断点 Breakpoint 2 set at 0x10b118f for main.counting() ./test.go:8
我们也可以使用"文件:行号"的格式来添加断点,如:
b /Users/user/go-learning/test.go:8 //等价于在函数counting处添加断点
然后继续程序运行,可见会先停在main函数处:
(dlv) c > main.main() ./test.go:16 (hits goroutine(1):1 total:1) (PC: 0x10b123b) 11: c <- i 12: } 13: close(c) 14: } 15: => 16: func main() { 17: msg := "Starting main" 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" 21: go counting(bus)
5)breakpoints(缩写bp)输出活动断点信息
(dlv) bp Breakpoint runtime-fatal-throw at 0x102b3e0 for runtime.fatalthrow() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:654 (0) Breakpoint unrecovered-panic at 0x102b450 for runtime.fatalpanic() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:681 (0) print runtime.curg._panic.arg Breakpoint 1 at 0x10b123b for main.main() ./test.go:16 (1) Breakpoint 2 at 0x10b118f for main.counting() ./test.go:8 (0)
可见上面的两个设置的断点
6)list 显示从停止行起前后5行的源代码
(dlv) list > main.main() ./test.go:16 (hits goroutine(1):1 total:1) (PC: 0x10b123b) 11: c <- i 12: } 13: close(c) 14: } 15: => 16: func main() { 17: msg := "Starting main" 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" 21: go counting(bus)
7)next (缩写n)转到下一个源行
可见现在的指针从16行转到了17行
如果想继续向下,可以直接回车,Delve会默认重复上一条命令
(dlv) n > main.main() ./test.go:17 (PC: 0x10b1252) 12: } 13: close(c) 14: } 15: 16: func main() { => 17: msg := "Starting main" 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" 21: go counting(bus) 22: for count := range bus{
8)print(缩写p)计算一个表达式
在这里用来打印一个变量的值,举例看下面
9)locals 打印局部变量
10)step(缩写s)单步执行程序
(dlv) p msg "H�\a\x00�\x00\x00\x00��\x05\x01\x00\x00\x00\x00\x00\x03\x00\x00�\x00\x00\x00��\a\x00�\x00\x00\x00�Q\x00\x01\x00\x00\x00\x00X�\x06\x00�\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00�\x0f\v\x01\x00\x00\x00\x00...+16825344 more" (dlv) locals msg = "H�\a\x00�\x00\x00\x00��\x05\x01\x00\x00\x00\x00\x00\x03\x00\x00�\x00\x00\x00��\a\x00�\x00\x00\x00�Q\x00\x01\x00\x00\x00\x00X�\x06\x00�\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00�\x0f\v\x01\x00\x00\x00\x00...+16825344 more" (dlv) p count Command failed: could not find symbol value for count (dlv) s > main.main() ./test.go:18 (PC: 0x10b1267) 13: close(c) 14: } 15: 16: func main() { 17: msg := "Starting main" => 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" 21: go counting(bus) 22: for count := range bus{ 23: fmt.Println("count : ", count) (dlv) p msg "Starting main" (dlv) locals msg = "Starting main"
在执行s前,使用p打印了msg局部变量的值,locals打印了局部变量的值,因为还没有运行到给msg复制的代码,所以返回的结果不是期望的值
然后当我们运行s后,可见指针也从17变成了18,然后这时候再运行p和locals,可见返回了期望的值
print还可以用来判断一个表达式:
(dlv) p msg == "Starting main" true
11)whatis打印表达式类型
(dlv) whatis msg string
能够得到msg变量为string类型
然后我们接着运行到下一个断点,这时候开启了一个groutine
(dlv) c Starting main > main.counting() ./test.go:8 (hits goroutine(18):1 total:1) (PC: 0x10b118f) 3: import ( 4: "fmt" 5: "time" 6: ) 7: => 8: func counting(c chan<- int){ 9: for i := 0; i < 10; i++{ 10: time.Sleep(2 * time.Second) 11: c <- i 12: } 13: close(c)
12)goroutine 显示或更改当前goroutine
(dlv) help goroutine goroutine goroutine <id> goroutine <id> <command> 调用时不带参数,它将显示关于当前goroutine的信息。 使用单个参数调用时,它将切换到指定的goroutine。 使用更多参数调用时,它将在指定的goroutine上执行命令。
可见现在正在运行的goroutine
(dlv) goroutine Thread 77795 at ./test.go:8 Goroutine 18: Runtime: ./test.go:8 main.counting (0x10b118f) User: ./test.go:8 main.counting (0x10b118f) Go: ./test.go:21 main.main (0x10b138a) Start: ./test.go:8 main.counting (0x10b1180)
指定查看的是goroutine 1 :
(dlv) goroutine 1 Switched from 18 to 1 (thread 77795) (dlv) goroutine Thread 77795 at ./test.go:8 Goroutine 1: Runtime: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:303 runtime.gopark (0x102d0f4) User: ./test.go:22 main.main (0x10b13ae) Go: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/asm_amd64.s:201 runtime.rt0_go (0x10557fb) Start: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:110 runtime.main (0x102cb60)
这时候如果运行locals,得到的是goroutine 1所在处的局部变量:
(dlv) locals gp = (*runtime.g)(0xc000000300) mp = (*runtime.m)(0x11904c0) status = (unreadable read out of bounds)
要回去原来的goroutine就调用:
(dlv) goroutine 18 Switched from 1 to 18 (thread 77795)
13)goroutines 列举程序goroutines
(dlv) help goroutines 列举程序goroutines. goroutines [-u (default: user location)|-r (runtime location)|-g (go statement location)|-s (start location)] [ -t (stack trace)] Print out info for every goroutine. The flag controls what information is shown along with each goroutine: -u 显示用户代码中最顶层堆栈帧的位置 -r 显示最顶层stackframe的位置(包括私有运行时函数中的帧) -g 显示创建goroutine的go指令的位置 -s 显示起始函数的位置 -t 显示goroutine的堆栈跟踪 如果没有指定具体的标志,则默认使用-u.
(dlv) goroutines Goroutine 1 - User: ./test.go:22 main.main (0x10b13ae) Goroutine 2 - User: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:303 runtime.gopark (0x102d0f4) Goroutine 3 - User: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:303 runtime.gopark (0x102d0f4) Goroutine 17 - User: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:303 runtime.gopark (0x102d0f4) * Goroutine 18 - User: ./test.go:8 main.counting (0x10b118f) (thread 77795) [5 goroutines] (dlv) goroutines -s Goroutine 1 - Start: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:110 runtime.main (0x102cb60) Goroutine 2 - Start: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:243 runtime.forcegchelper (0x102ced0) Goroutine 3 - Start: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/mgcsweep.go:46 runtime.bgsweep (0x1020170) Goroutine 17 - Start: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/mfinal.go:161 runtime.runfinq (0x1017ae0) * Goroutine 18 - Start: ./test.go:8 main.counting (0x10b1180) (thread 77795) [5 goroutines]
14)args 打印函数参数
得到counting函数的参数值:
(dlv) args c = chan<- int 0/0
因为之前只设置了两个断点,因此再次调用c则又将运行程序完毕:
(dlv) c count : 0 count : 1
...
15)stepout 跳出当前函数
(dlv) restart Process restarted with PID 1352 (dlv) b main.main //之前的断点一直存在,即使程序结束,因此此时的counting函数中也有断点 Command failed: Breakpoint exists at /Users/user/go-learning/test.go:16 at 10b123b (dlv) c > main.main() ./test.go:16 (hits goroutine(1):1 total:1) (PC: 0x10b123b) 11: c <- i 12: } 13: close(c) 14: } 15: => 16: func main() { 17: msg := "Starting main" 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" 21: go counting(bus) (dlv) stepout Starting main > main.counting() ./test.go:8 (hits goroutine(5):1 total:1) (PC: 0x10b118f) breakpoint hit during stepout, continuing... count : 0 count : 1 count : 2 ...
因为stepout跳过的是main()函数,可见直接也跳过了counting的断点,然后执行程序到结束
16)clear删除断点\clearall删除多个断点
因为如果不手动清除断点,即使程序结束并restart程序,断点信息也仍然在
(dlv) breakpoints //查看当前的断点信息 Breakpoint runtime-fatal-throw at 0x102b3e0 for runtime.fatalthrow() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:654 (0) Breakpoint unrecovered-panic at 0x102b450 for runtime.fatalpanic() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:681 (0) print runtime.curg._panic.arg Breakpoint 1 at 0x10b123b for main.main() ./test.go:16 (1) Breakpoint 2 at 0x10b118f for main.counting() ./test.go:8 (0) (dlv) clear 1 //先删除第一个断点,即main函数上的断点 Breakpoint 1 cleared at 0x10b123b for main.main() ./test.go:16 (dlv) breakpoints //查看可见果然成功删除 Breakpoint runtime-fatal-throw at 0x102b3e0 for runtime.fatalthrow() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:654 (0) Breakpoint unrecovered-panic at 0x102b450 for runtime.fatalpanic() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:681 (0) print runtime.curg._panic.arg Breakpoint 2 at 0x10b118f for main.counting() ./test.go:8 (0) (dlv) clearall //然后将所有断点都删除 Breakpoint 2 cleared at 0x10b118f for main.counting() ./test.go:8 (dlv) breakpoints //查看可见断点信息为空 Breakpoint runtime-fatal-throw at 0x102b3e0 for runtime.fatalthrow() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:654 (0) Breakpoint unrecovered-panic at 0x102b450 for runtime.fatalpanic() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:681 (0) print runtime.curg._panic.arg (dlv)
17)on 在命中断点时执行命令
(dlv) help on Executes a command when a breakpoint is hit. on <breakpoint name or id> <command>. Supported commands: print, stack and goroutine)
(dlv) b /Users/user/go-learning/test.go:21 //添加断点 Breakpoint 2 set at 0x10b1368 for main.main() ./test.go:21 (dlv) on 2 print msg == "starting a gofunc" //设置当到达该断点后运行的命令,即判断msg的值是否为"starting a gofunc" (dlv) breakpoints //查看此时的断点信息 Breakpoint runtime-fatal-throw at 0x102b3e0 for runtime.fatalthrow() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:654 (0) Breakpoint unrecovered-panic at 0x102b450 for runtime.fatalpanic() /usr/local/Cellar/go/1.11.4/libexec/src/runtime/panic.go:681 (0) print runtime.curg._panic.arg Breakpoint 2 at 0x10b1368 for main.main() ./test.go:21 (0) print msg == "starting a gofunc" (dlv) c Starting main > main.main() ./test.go:21 (hits goroutine(1):1 total:1) (PC: 0x10b1368) msg == "starting a gofunc": true //可见打印出来了,并返回值为true 16: func main() { 17: msg := "Starting main" 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" => 21: go counting(bus) 22: for count := range bus{ 23: fmt.Println("count : ", count) 24: } 25: }
18)set 更改变量的值
(dlv) help set Changes the value of a variable. [goroutine <n>] [frame <m>] set <variable> = <value>
⚠️Only numerical variables and pointers can be changed.
因此更改string类型变量将报错:
(dlv) set msg = "change msg" Command failed: can not set variables of type string (not implemented)
19)up向上移动当前帧/dowm向下移动当前帧
(dlv) up > main.main() ./test.go:21 (hits goroutine(1):1 total:1) (PC: 0x10b1368) Frame 1: /usr/local/Cellar/go/1.11.4/libexec/src/runtime/proc.go:201 (PC: 102cd25) 196: // A program compiled with -buildmode=c-archive or c-shared 197: // has a main, but it is not executed. 198: return 199: } 200: fn = main_main // make an indirect call, as the linker doesn't know the address of the main package when laying down the runtime => 201: fn() 202: if raceenabled { 203: racefini() 204: } 205: 206: // Make racy client program work: if panicking on (dlv) down > main.main() ./test.go:21 (hits goroutine(1):1 total:1) (PC: 0x10b1368) Frame 0: ./test.go:21 (PC: 10b1368) 16: func main() { 17: msg := "Starting main" 18: fmt.Println(msg) 19: bus := make(chan int) 20: msg = "starting a gofunc" => 21: go counting(bus) 22: for count := range bus{ 23: fmt.Println("count : ", count) 24: } 25: }
20)exit (alias: quit | q)退出调试器
(dlv) exit
userdeMBP:go-learning user$
3.dlv attach
如果项目正在运行中,想要对正在运行的项目进行调试
1)首先使用"ps aux | grep 编译文件名"来查看运行程序的进程号pid
2)然后就能够使用"dlv attach pid"来连接该运行程序,然后就能使用之前debug中的命令来进行调试了
其他的命令之后如果用到了再添加