Files
polaris/vendor/github.com/pkg/errors/stack.go
Bobby Brennan 54a4f92695 Pack static assets into packr box for portability
copy config.yaml to docker image

enable external usage of dashboard package

gofmt

fix comment

use packr for assets

add gobuffalo/packr dependency

add dependencies

fix pointer issues

add output-file option
2019-04-18 18:25:16 +00:00

148 lines
3.3 KiB
Go

package errors
import (
"fmt"
"io"
"path"
"runtime"
"strings"
)
// Frame represents a program counter inside a stack frame.
type Frame uintptr
// pc returns the program counter for this frame;
// multiple frames may have the same PC value.
func (f Frame) pc() uintptr { return uintptr(f) - 1 }
// file returns the full path to the file that contains the
// function for this Frame's pc.
func (f Frame) file() string {
fn := runtime.FuncForPC(f.pc())
if fn == nil {
return "unknown"
}
file, _ := fn.FileLine(f.pc())
return file
}
// line returns the line number of source code of the
// function for this Frame's pc.
func (f Frame) line() int {
fn := runtime.FuncForPC(f.pc())
if fn == nil {
return 0
}
_, line := fn.FileLine(f.pc())
return line
}
// Format formats the frame according to the fmt.Formatter interface.
//
// %s source file
// %d source line
// %n function name
// %v equivalent to %s:%d
//
// Format accepts flags that alter the printing of some verbs, as follows:
//
// %+s function name and path of source file relative to the compile time
// GOPATH separated by \n\t (<funcname>\n\t<path>)
// %+v equivalent to %+s:%d
func (f Frame) Format(s fmt.State, verb rune) {
switch verb {
case 's':
switch {
case s.Flag('+'):
pc := f.pc()
fn := runtime.FuncForPC(pc)
if fn == nil {
io.WriteString(s, "unknown")
} else {
file, _ := fn.FileLine(pc)
fmt.Fprintf(s, "%s\n\t%s", fn.Name(), file)
}
default:
io.WriteString(s, path.Base(f.file()))
}
case 'd':
fmt.Fprintf(s, "%d", f.line())
case 'n':
name := runtime.FuncForPC(f.pc()).Name()
io.WriteString(s, funcname(name))
case 'v':
f.Format(s, 's')
io.WriteString(s, ":")
f.Format(s, 'd')
}
}
// StackTrace is stack of Frames from innermost (newest) to outermost (oldest).
type StackTrace []Frame
// Format formats the stack of Frames according to the fmt.Formatter interface.
//
// %s lists source files for each Frame in the stack
// %v lists the source file and line number for each Frame in the stack
//
// Format accepts flags that alter the printing of some verbs, as follows:
//
// %+v Prints filename, function, and line number for each Frame in the stack.
func (st StackTrace) Format(s fmt.State, verb rune) {
switch verb {
case 'v':
switch {
case s.Flag('+'):
for _, f := range st {
fmt.Fprintf(s, "\n%+v", f)
}
case s.Flag('#'):
fmt.Fprintf(s, "%#v", []Frame(st))
default:
fmt.Fprintf(s, "%v", []Frame(st))
}
case 's':
fmt.Fprintf(s, "%s", []Frame(st))
}
}
// stack represents a stack of program counters.
type stack []uintptr
func (s *stack) Format(st fmt.State, verb rune) {
switch verb {
case 'v':
switch {
case st.Flag('+'):
for _, pc := range *s {
f := Frame(pc)
fmt.Fprintf(st, "\n%+v", f)
}
}
}
}
func (s *stack) StackTrace() StackTrace {
f := make([]Frame, len(*s))
for i := 0; i < len(f); i++ {
f[i] = Frame((*s)[i])
}
return f
}
func callers() *stack {
const depth = 32
var pcs [depth]uintptr
n := runtime.Callers(3, pcs[:])
var st stack = pcs[0:n]
return &st
}
// funcname removes the path prefix component of a function's name reported by func.Name().
func funcname(name string) string {
i := strings.LastIndex(name, "/")
name = name[i+1:]
i = strings.Index(name, ".")
return name[i+1:]
}