status-go/vendor/go.uber.org/fx/internal/fxreflect/stack.go

159 lines
4.3 KiB
Go

// Copyright (c) 2019 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package fxreflect
import (
"fmt"
"io"
"runtime"
"strings"
)
// Frame holds information about a single frame in the call stack.
type Frame struct {
// Unique, package path-qualified name for the function of this call
// frame.
Function string
// File and line number of our location in the frame.
//
// Note that the line number does not refer to where the function was
// defined but where in the function the next call was made.
File string
Line int
}
func (f Frame) String() string {
// This takes the following forms.
// (path/to/file.go)
// (path/to/file.go:42)
// path/to/package.MyFunction
// path/to/package.MyFunction (path/to/file.go)
// path/to/package.MyFunction (path/to/file.go:42)
var sb strings.Builder
sb.WriteString(f.Function)
if len(f.File) > 0 {
if sb.Len() > 0 {
sb.WriteRune(' ')
}
fmt.Fprintf(&sb, "(%v", f.File)
if f.Line > 0 {
fmt.Fprintf(&sb, ":%d", f.Line)
}
sb.WriteRune(')')
}
if sb.Len() == 0 {
return "unknown"
}
return sb.String()
}
const _defaultCallersDepth = 8
// Stack is a stack of call frames.
//
// Formatted with %v, the output is in a single-line, in the form,
//
// foo/bar.Baz() (path/to/foo.go:42); bar/baz.Qux() (bar/baz/qux.go:12); ...
//
// Formatted with %+v, the output is in the form,
//
// foo/bar.Baz()
// path/to/foo.go:42
// bar/baz.Qux()
// bar/baz/qux.go:12
type Stack []Frame
// String returns a single-line, semi-colon representation of a Stack.
// For a list of strings where each represents one frame, use Strings.
// For a cleaner multi-line representation, use %+v.
func (fs Stack) String() string {
return strings.Join(fs.Strings(), "; ")
}
// Strings returns a list of strings, each representing a frame in the stack.
// Each line will be in the form,
//
// foo/bar.Baz() (path/to/foo.go:42)
func (fs Stack) Strings() []string {
items := make([]string, len(fs))
for i, f := range fs {
items[i] = f.String()
}
return items
}
// Format implements fmt.Formatter to handle "%+v".
func (fs Stack) Format(w fmt.State, c rune) {
if !w.Flag('+') {
// Without %+v, fall back to String().
io.WriteString(w, fs.String())
return
}
for _, f := range fs {
fmt.Fprintln(w, f.Function)
fmt.Fprintf(w, "\t%v:%v\n", f.File, f.Line)
}
}
// CallerName returns the name of the first caller in this stack that isn't
// owned by the Fx library.
func (fs Stack) CallerName() string {
for _, f := range fs {
if shouldIgnoreFrame(f) {
continue
}
return f.Function
}
return "n/a"
}
// CallerStack returns the call stack for the calling function, up to depth frames
// deep, skipping the provided number of frames, not including Callers itself.
//
// If zero, depth defaults to 8.
func CallerStack(skip, depth int) Stack {
if depth <= 0 {
depth = _defaultCallersDepth
}
pcs := make([]uintptr, depth)
// +2 to skip this frame and runtime.Callers.
n := runtime.Callers(skip+2, pcs)
pcs = pcs[:n] // truncate to number of frames actually read
result := make([]Frame, 0, n)
frames := runtime.CallersFrames(pcs)
for f, more := frames.Next(); more; f, more = frames.Next() {
result = append(result, Frame{
Function: sanitize(f.Function),
File: f.File,
Line: f.Line,
})
}
return result
}