fermentord/vendor/github.com/getsentry/sentry-go/stacktrace.go

381 lines
11 KiB
Go

package sentry
import (
"go/build"
"reflect"
"runtime"
"strings"
)
const unknown string = "unknown"
// The module download is split into two parts: downloading the go.mod and downloading the actual code.
// If you have dependencies only needed for tests, then they will show up in your go.mod,
// and go get will download their go.mods, but it will not download their code.
// The test-only dependencies get downloaded only when you need it, such as the first time you run go test.
//
// https://github.com/golang/go/issues/26913#issuecomment-411976222
// Stacktrace holds information about the frames of the stack.
type Stacktrace struct {
Frames []Frame `json:"frames,omitempty"`
FramesOmitted []uint `json:"frames_omitted,omitempty"`
}
// NewStacktrace creates a stacktrace using runtime.Callers.
func NewStacktrace() *Stacktrace {
pcs := make([]uintptr, 100)
n := runtime.Callers(1, pcs)
if n == 0 {
return nil
}
runtimeFrames := extractFrames(pcs[:n])
frames := createFrames(runtimeFrames)
stacktrace := Stacktrace{
Frames: frames,
}
return &stacktrace
}
// TODO: Make it configurable so that anyone can provide their own implementation?
// Use of reflection allows us to not have a hard dependency on any given
// package, so we don't have to import it.
// ExtractStacktrace creates a new Stacktrace based on the given error.
func ExtractStacktrace(err error) *Stacktrace {
method := extractReflectedStacktraceMethod(err)
var pcs []uintptr
if method.IsValid() {
pcs = extractPcs(method)
} else {
pcs = extractXErrorsPC(err)
}
if len(pcs) == 0 {
return nil
}
runtimeFrames := extractFrames(pcs)
frames := createFrames(runtimeFrames)
stacktrace := Stacktrace{
Frames: frames,
}
return &stacktrace
}
func extractReflectedStacktraceMethod(err error) reflect.Value {
errValue := reflect.ValueOf(err)
// https://github.com/go-errors/errors
methodStackFrames := errValue.MethodByName("StackFrames")
if methodStackFrames.IsValid() {
return methodStackFrames
}
// https://github.com/pkg/errors
methodStackTrace := errValue.MethodByName("StackTrace")
if methodStackTrace.IsValid() {
return methodStackTrace
}
// https://github.com/pingcap/errors
methodGetStackTracer := errValue.MethodByName("GetStackTracer")
if methodGetStackTracer.IsValid() {
stacktracer := methodGetStackTracer.Call(nil)[0]
stacktracerStackTrace := reflect.ValueOf(stacktracer).MethodByName("StackTrace")
if stacktracerStackTrace.IsValid() {
return stacktracerStackTrace
}
}
return reflect.Value{}
}
func extractPcs(method reflect.Value) []uintptr {
var pcs []uintptr
stacktrace := method.Call(nil)[0]
if stacktrace.Kind() != reflect.Slice {
return nil
}
for i := 0; i < stacktrace.Len(); i++ {
pc := stacktrace.Index(i)
switch pc.Kind() {
case reflect.Uintptr:
pcs = append(pcs, uintptr(pc.Uint()))
case reflect.Struct:
for _, fieldName := range []string{"ProgramCounter", "PC"} {
field := pc.FieldByName(fieldName)
if !field.IsValid() {
continue
}
if field.Kind() == reflect.Uintptr {
pcs = append(pcs, uintptr(field.Uint()))
break
}
}
}
}
return pcs
}
// extractXErrorsPC extracts program counters from error values compatible with
// the error types from golang.org/x/xerrors.
//
// It returns nil if err is not compatible with errors from that package or if
// no program counters are stored in err.
func extractXErrorsPC(err error) []uintptr {
// This implementation uses the reflect package to avoid a hard dependency
// on third-party packages.
// We don't know if err matches the expected type. For simplicity, instead
// of trying to account for all possible ways things can go wrong, some
// assumptions are made and if they are violated the code will panic. We
// recover from any panic and ignore it, returning nil.
//nolint: errcheck
defer func() { recover() }()
field := reflect.ValueOf(err).Elem().FieldByName("frame") // type Frame struct{ frames [3]uintptr }
field = field.FieldByName("frames")
field = field.Slice(1, field.Len()) // drop first pc pointing to xerrors.New
pc := make([]uintptr, field.Len())
for i := 0; i < field.Len(); i++ {
pc[i] = uintptr(field.Index(i).Uint())
}
return pc
}
// Frame represents a function call and it's metadata. Frames are associated
// with a Stacktrace.
type Frame struct {
Function string `json:"function,omitempty"`
Symbol string `json:"symbol,omitempty"`
// Module is, despite the name, the Sentry protocol equivalent of a Go
// package's import path.
Module string `json:"module,omitempty"`
Filename string `json:"filename,omitempty"`
AbsPath string `json:"abs_path,omitempty"`
Lineno int `json:"lineno,omitempty"`
Colno int `json:"colno,omitempty"`
PreContext []string `json:"pre_context,omitempty"`
ContextLine string `json:"context_line,omitempty"`
PostContext []string `json:"post_context,omitempty"`
InApp bool `json:"in_app"`
Vars map[string]interface{} `json:"vars,omitempty"`
// Package and the below are not used for Go stack trace frames. In
// other platforms it refers to a container where the Module can be
// found. For example, a Java JAR, a .NET Assembly, or a native
// dynamic library. They exists for completeness, allowing the
// construction and reporting of custom event payloads.
Package string `json:"package,omitempty"`
InstructionAddr string `json:"instruction_addr,omitempty"`
AddrMode string `json:"addr_mode,omitempty"`
SymbolAddr string `json:"symbol_addr,omitempty"`
ImageAddr string `json:"image_addr,omitempty"`
Platform string `json:"platform,omitempty"`
StackStart bool `json:"stack_start,omitempty"`
}
// NewFrame assembles a stacktrace frame out of runtime.Frame.
func NewFrame(f runtime.Frame) Frame {
function := f.Function
var pkg string
if function != "" {
pkg, function = splitQualifiedFunctionName(function)
}
return newFrame(pkg, function, f.File, f.Line)
}
// Like filepath.IsAbs() but doesn't care what platform you run this on.
// I.e. it also recognizies `/path/to/file` when run on Windows.
func isAbsPath(path string) bool {
if len(path) == 0 {
return false
}
// If the volume name starts with a double slash, this is an absolute path.
if len(path) >= 1 && (path[0] == '/' || path[0] == '\\') {
return true
}
// Windows absolute path, see https://learn.microsoft.com/en-us/dotnet/standard/io/file-path-formats
if len(path) >= 3 && path[1] == ':' && (path[2] == '/' || path[2] == '\\') {
return true
}
return false
}
func newFrame(module string, function string, file string, line int) Frame {
frame := Frame{
Lineno: line,
Module: module,
Function: function,
}
switch {
case len(file) == 0:
frame.Filename = unknown
// Leave abspath as the empty string to be omitted when serializing event as JSON.
case isAbsPath(file):
frame.AbsPath = file
// TODO: in the general case, it is not trivial to come up with a
// "project relative" path with the data we have in run time.
// We shall not use filepath.Base because it creates ambiguous paths and
// affects the "Suspect Commits" feature.
// For now, leave relpath empty to be omitted when serializing the event
// as JSON. Improve this later.
default:
// f.File is a relative path. This may happen when the binary is built
// with the -trimpath flag.
frame.Filename = file
// Omit abspath when serializing the event as JSON.
}
setInAppFrame(&frame)
return frame
}
// splitQualifiedFunctionName splits a package path-qualified function name into
// package name and function name. Such qualified names are found in
// runtime.Frame.Function values.
func splitQualifiedFunctionName(name string) (pkg string, fun string) {
pkg = packageName(name)
if len(pkg) > 0 {
fun = name[len(pkg)+1:]
}
return
}
func extractFrames(pcs []uintptr) []runtime.Frame {
var frames = make([]runtime.Frame, 0, len(pcs))
callersFrames := runtime.CallersFrames(pcs)
for {
callerFrame, more := callersFrames.Next()
frames = append(frames, callerFrame)
if !more {
break
}
}
// TODO don't append and reverse, put in the right place from the start.
// reverse
for i, j := 0, len(frames)-1; i < j; i, j = i+1, j-1 {
frames[i], frames[j] = frames[j], frames[i]
}
return frames
}
// createFrames creates Frame objects while filtering out frames that are not
// meant to be reported to Sentry, those are frames internal to the SDK or Go.
func createFrames(frames []runtime.Frame) []Frame {
if len(frames) == 0 {
return nil
}
result := make([]Frame, 0, len(frames))
for _, frame := range frames {
function := frame.Function
var pkg string
if function != "" {
pkg, function = splitQualifiedFunctionName(function)
}
if !shouldSkipFrame(pkg) {
result = append(result, newFrame(pkg, function, frame.File, frame.Line))
}
}
return result
}
// TODO ID: why do we want to do this?
// I'm not aware of other SDKs skipping all Sentry frames, regardless of their position in the stactrace.
// For example, in the .NET SDK, only the first frames are skipped until the call to the SDK.
// As is, this will also hide any intermediate frames in the stack and make debugging issues harder.
func shouldSkipFrame(module string) bool {
// Skip Go internal frames.
if module == "runtime" || module == "testing" {
return true
}
// Skip Sentry internal frames, except for frames in _test packages (for testing).
if strings.HasPrefix(module, "github.com/getsentry/sentry-go") &&
!strings.HasSuffix(module, "_test") {
return true
}
return false
}
// On Windows, GOROOT has backslashes, but we want forward slashes.
var goRoot = strings.ReplaceAll(build.Default.GOROOT, "\\", "/")
func setInAppFrame(frame *Frame) {
if strings.HasPrefix(frame.AbsPath, goRoot) ||
strings.Contains(frame.Module, "vendor") ||
strings.Contains(frame.Module, "third_party") {
frame.InApp = false
} else {
frame.InApp = true
}
}
func callerFunctionName() string {
pcs := make([]uintptr, 1)
runtime.Callers(3, pcs)
callersFrames := runtime.CallersFrames(pcs)
callerFrame, _ := callersFrames.Next()
return baseName(callerFrame.Function)
}
// packageName returns the package part of the symbol name, or the empty string
// if there is none.
// It replicates https://golang.org/pkg/debug/gosym/#Sym.PackageName, avoiding a
// dependency on debug/gosym.
func packageName(name string) string {
if isCompilerGeneratedSymbol(name) {
return ""
}
pathend := strings.LastIndex(name, "/")
if pathend < 0 {
pathend = 0
}
if i := strings.Index(name[pathend:], "."); i != -1 {
return name[:pathend+i]
}
return ""
}
// baseName returns the symbol name without the package or receiver name.
// It replicates https://golang.org/pkg/debug/gosym/#Sym.BaseName, avoiding a
// dependency on debug/gosym.
func baseName(name string) string {
if i := strings.LastIndex(name, "."); i != -1 {
return name[i+1:]
}
return name
}