stack

Documentation

Overview

Package stack implements utilities to capture, manipulate, and format call stacks.

Index

• type Call
  • func (pc Call) Format(s fmt.State, c rune)
• type Trace
  • func Callers() Trace
  • func (pcs Trace) Format(s fmt.State, c rune)
  • func (pcs Trace) TrimAbove(pc Call) Trace
  • func (pcs Trace) TrimAboveName(name string) Trace
  • func (pcs Trace) TrimBelow(pc Call) Trace
  • func (pcs Trace) TrimBelowName(name string) Trace
  • func (pcs Trace) TrimRuntime() Trace
• Bugs

Types

type Call

type Call uintptr

Call records a single function invocation from a goroutine stack. It is a wrapper for the program counter values returned by runtime.Caller and runtime.Callers and consumed by runtime.FuncForPC.

func (Call) Format

func (pc Call) Format(s fmt.State, c rune)

Format implements fmt.Formatter with support for the following verbs.

%s    source file
%d    line number
%n    function name
%v    equivalent to %s:%d

It accepts the '+' and '#' flags for most of the verbs as follows.

%+s   path of source file relative to the compile time GOPATH
%#s   full path of source file
%+n   import path qualified function name
%+v   equivalent to %+s:%d
%#v   equivalent to %#s:%d

type Trace

type Trace []Call

Trace records a sequence of function invocations from a goroutine stack.

func Callers

func Callers() Trace

Callers returns a Trace for the current goroutine with element 0 identifying the calling function.

func (Trace) Format

func (pcs Trace) Format(s fmt.State, c rune)

Format implements fmt.Formatter by printing the Trace as square brackes ([, ]) surrounding a space separated list of Calls each formatted with the supplied verb and options.

func (Trace) TrimAbove

func (pcs Trace) TrimAbove(pc Call) Trace

TrimAbove returns a slice of the Trace with all entries above pc removed.

func (Trace) TrimAboveName

func (pcs Trace) TrimAboveName(name string) Trace

TrimAboveName returns a slice of the Trace with all entries above the highest with function name name removed.

func (Trace) TrimBelow

func (pcs Trace) TrimBelow(pc Call) Trace

TrimBelow returns a slice of the Trace with all entries below pc removed.

func (Trace) TrimBelowName

func (pcs Trace) TrimBelowName(name string) Trace

TrimBelowName returns a slice of the Trace with all entries below the lowest with function name name removed.

func (Trace) TrimRuntime

func (pcs Trace) TrimRuntime() Trace

TrimRuntime returns a slice of the Trace with the topmost entries from the go runtime removed. It considers any calls originating from files under GOROOT as part of the runtime.

Notes

Bugs

• Subtracting one from pc is a work around for https://code.google.com/p/go/issues/detail?id=7690. The idea for this work around comes from rsc's initial patch at https://codereview.appspot.com/84100043/#ps20001, but as noted in the issue discussion, it is not a complete fix since it doesn't handle some cases involving signals. Just the same, it handles all of the other cases I have tested.