pdebug

Documentation

Index

• func NewStack(skipFrames int) (stack parl.Stack)
• func ParseCreatedLine(createdLine []byte) (funcName string, IsMainThread bool)
• func ParseFileLine(fileLine []byte) (file string, line int)
• func ParseFirstLine(debugStack []byte) (ID parl.ThreadID, status parl.ThreadStatus, err error)
• func ParseFuncLine(funcLine []byte) (funcName string, args string)
• type Frame
  • func (f *Frame) Args() (args string)
  • func (f *Frame) Loc() (location *pruntime.CodeLocation)
  • func (f *Frame) String() (s string)
• type Stack
  • func (s *Stack) Creator() (creator *pruntime.CodeLocation)
  • func (s *Stack) Frames() (frames []parl.Frame)
  • func (s *Stack) GoFunction() (goFunction *pruntime.CodeLocation)
  • func (s *Stack) ID() (threadID parl.ThreadID)
  • func (s *Stack) IsMain() (isMainThread bool)
  • func (s *Stack) MostRecentFrame() (frame parl.Frame)
  • func (s *Stack) SetCreator(creator *pruntime.CodeLocation, isMainThread bool)
  • func (s *Stack) SetFrames(frames []parl.Frame)
  • func (s *Stack) SetID(threadID parl.ThreadID, status parl.ThreadStatus)
  • func (s *Stack) Shorts(prepend string) (shorts string)
  • func (s *Stack) Status() (status parl.ThreadStatus)
  • func (s *Stack) String() (str string)

Functions

func NewStack

func NewStack(skipFrames int) (stack parl.Stack)

NewStack populates a Stack object with the current thread and its stack using debug.Stack

func ParseCreatedLine

func ParseCreatedLine(createdLine []byte) (funcName string, IsMainThread bool)

ParseCreatedLine parses the second-to-last line of the stack trace. samples:

• “created by main.main”
• “created by main.(*MyType).goroutine1”
• “main.main()”

func ParseFileLine

func ParseFileLine(fileLine []byte) (file string, line int)

ParseFileLine parses a line of a tab character then absolue file path, followed by a colon and line number, then a space character and a byte offset.

"\t/gp-debug-stack/debug-stack.go:29 +0x44"
"\t/opt/sw/parl/g0/waiterr.go:49"

func ParseFirstLine

func ParseFirstLine(debugStack []byte) (ID parl.ThreadID, status parl.ThreadStatus, err error)

getID obtains gorutine ID, as of go1.18 a numeric string "1"…

func ParseFuncLine

func ParseFuncLine(funcLine []byte) (funcName string, args string)

ParseFuncLine parses a line of a package name, optionally fully qualified, and a possible receiver type name and a function name, followed by a parenthesised argument list. samples:

main.main()
main.(*MyType).goroutine1(0x0?, 0x140000120d0, 0x2)
codeberg.org/haraldrudell/goprogramming/std/runtime-debug/gp-debug-stack/mypackage.Fn(...)

Types

type Frame

type Frame struct {
	pruntime.CodeLocation
	// contains filtered or unexported fields
}

Frame represents an executing code location, ie. a code line in source code

• parl.Frame is similar to runtime.Frame returned by runtime.CallersFrames but has only basic types, ie. can be stored or transferred
• pdebug.Frame implements parl.Frame
• Frame is a value container only created by pdebug.NewStack. Frame extends pruntime.CodeLocation with argument values

func (*Frame) Args

func (f *Frame) Args() (args string)

function argument values like "(1, 0x14000113040)"

• values of basic types like int are displayed
• most types appear as a pointer value “0x…”

func (*Frame) Loc

func (f *Frame) Loc() (location *pruntime.CodeLocation)

the code location for this frame, never nil

func (*Frame) String

func (f *Frame) String() (s string)

prints the Frame suitable to be part of a stack trace

• fully qualified package name with function or type and method and argument values
• absolute path to source file and line number

output:

github.com/haraldrudell/parl/pdebug.TestFrame(0x1400014a340)␤
␠␠frame_test.go:15

type Stack

type Stack struct {
	// contains filtered or unexported fields
}

• Go stack traces are created by runtime.Stack and is a byte slice
• [debug.Stack] repeatedly calls runtime.Stack with an increased buffer size that is eventually returned
• [debug.PrintStack] writes the byte stream to os.Stderr
• interning large strings is a temporary memory leak. Converting the entire byte-slice stack-trace to string retains the memory for as long as there is a reference to any one character. This leads to megabytes of memory leaks

func (*Stack) Creator

func (s *Stack) Creator() (creator *pruntime.CodeLocation)

func (*Stack) Frames

func (s *Stack) Frames() (frames []parl.Frame)

func (*Stack) GoFunction

func (s *Stack) GoFunction() (goFunction *pruntime.CodeLocation)

func (*Stack) ID

func (s *Stack) ID() (threadID parl.ThreadID)

func (*Stack) IsMain

func (s *Stack) IsMain() (isMainThread bool)

func (*Stack) MostRecentFrame

func (s *Stack) MostRecentFrame() (frame parl.Frame)

func (*Stack) SetCreator

func (s *Stack) SetCreator(creator *pruntime.CodeLocation, isMainThread bool)

SetCreator is used if Stack is for a goroutine

• describing whether it is the main thread
• if a gouroutine, where the launching go statement was located

func (*Stack) SetFrames

func (s *Stack) SetFrames(frames []parl.Frame)

func (*Stack) SetID

func (s *Stack) SetID(threadID parl.ThreadID, status parl.ThreadStatus)

SetID updates goroutine ID and thread status from the stack trace status line

func (*Stack) Shorts

func (s *Stack) Shorts(prepend string) (shorts string)

func (*Stack) Status

func (s *Stack) Status() (status parl.ThreadStatus)

func (*Stack) String

func (s *Stack) String() (str string)