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authorKali Kaneko (leap communications) <kali@leap.se>2019-01-12 18:39:45 +0100
committerRuben Pollan <meskio@sindominio.net>2019-01-17 12:30:32 +0100
commitb1247d2d0d51108c910a73891ff3116e5f032ab1 (patch)
treee9948964f0bfb1ad2df3bc7bad02aa1f41ccfbd8 /vendor/github.com/go-stack/stack/stack.go
parentefcb8312e31b5c2261b1a1e95ace55b322cfcc27 (diff)
[pkg] all your deps are vendored to us
Diffstat (limited to 'vendor/github.com/go-stack/stack/stack.go')
-rw-r--r--vendor/github.com/go-stack/stack/stack.go400
1 files changed, 400 insertions, 0 deletions
diff --git a/vendor/github.com/go-stack/stack/stack.go b/vendor/github.com/go-stack/stack/stack.go
new file mode 100644
index 0000000..ac3b93b
--- /dev/null
+++ b/vendor/github.com/go-stack/stack/stack.go
@@ -0,0 +1,400 @@
+// +build go1.7
+
+// Package stack implements utilities to capture, manipulate, and format call
+// stacks. It provides a simpler API than package runtime.
+//
+// The implementation takes care of the minutia and special cases of
+// interpreting the program counter (pc) values returned by runtime.Callers.
+//
+// Package stack's types implement fmt.Formatter, which provides a simple and
+// flexible way to declaratively configure formatting when used with logging
+// or error tracking packages.
+package stack
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "runtime"
+ "strconv"
+ "strings"
+)
+
+// Call records a single function invocation from a goroutine stack.
+type Call struct {
+ frame runtime.Frame
+}
+
+// Caller returns a Call from the stack of the current goroutine. The argument
+// skip is the number of stack frames to ascend, with 0 identifying the
+// calling function.
+func Caller(skip int) Call {
+ // As of Go 1.9 we need room for up to three PC entries.
+ //
+ // 0. An entry for the stack frame prior to the target to check for
+ // special handling needed if that prior entry is runtime.sigpanic.
+ // 1. A possible second entry to hold metadata about skipped inlined
+ // functions. If inline functions were not skipped the target frame
+ // PC will be here.
+ // 2. A third entry for the target frame PC when the second entry
+ // is used for skipped inline functions.
+ var pcs [3]uintptr
+ n := runtime.Callers(skip+1, pcs[:])
+ frames := runtime.CallersFrames(pcs[:n])
+ frame, _ := frames.Next()
+ frame, _ = frames.Next()
+
+ return Call{
+ frame: frame,
+ }
+}
+
+// String implements fmt.Stinger. It is equivalent to fmt.Sprintf("%v", c).
+func (c Call) String() string {
+ return fmt.Sprint(c)
+}
+
+// MarshalText implements encoding.TextMarshaler. It formats the Call the same
+// as fmt.Sprintf("%v", c).
+func (c Call) MarshalText() ([]byte, error) {
+ if c.frame == (runtime.Frame{}) {
+ return nil, ErrNoFunc
+ }
+
+ buf := bytes.Buffer{}
+ fmt.Fprint(&buf, c)
+ return buf.Bytes(), nil
+}
+
+// ErrNoFunc means that the Call has a nil *runtime.Func. The most likely
+// cause is a Call with the zero value.
+var ErrNoFunc = errors.New("no call stack information")
+
+// Format implements fmt.Formatter with support for the following verbs.
+//
+// %s source file
+// %d line number
+// %n function name
+// %k last segment of the package path
+// %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,
+// or the module path joined to the path of source file relative
+// to module root
+// %#s full path of source file
+// %+n import path qualified function name
+// %+k full package path
+// %+v equivalent to %+s:%d
+// %#v equivalent to %#s:%d
+func (c Call) Format(s fmt.State, verb rune) {
+ if c.frame == (runtime.Frame{}) {
+ fmt.Fprintf(s, "%%!%c(NOFUNC)", verb)
+ return
+ }
+
+ switch verb {
+ case 's', 'v':
+ file := c.frame.File
+ switch {
+ case s.Flag('#'):
+ // done
+ case s.Flag('+'):
+ file = pkgFilePath(&c.frame)
+ default:
+ const sep = "/"
+ if i := strings.LastIndex(file, sep); i != -1 {
+ file = file[i+len(sep):]
+ }
+ }
+ io.WriteString(s, file)
+ if verb == 'v' {
+ buf := [7]byte{':'}
+ s.Write(strconv.AppendInt(buf[:1], int64(c.frame.Line), 10))
+ }
+
+ case 'd':
+ buf := [6]byte{}
+ s.Write(strconv.AppendInt(buf[:0], int64(c.frame.Line), 10))
+
+ case 'k':
+ name := c.frame.Function
+ const pathSep = "/"
+ start, end := 0, len(name)
+ if i := strings.LastIndex(name, pathSep); i != -1 {
+ start = i + len(pathSep)
+ }
+ const pkgSep = "."
+ if i := strings.Index(name[start:], pkgSep); i != -1 {
+ end = start + i
+ }
+ if s.Flag('+') {
+ start = 0
+ }
+ io.WriteString(s, name[start:end])
+
+ case 'n':
+ name := c.frame.Function
+ if !s.Flag('+') {
+ const pathSep = "/"
+ if i := strings.LastIndex(name, pathSep); i != -1 {
+ name = name[i+len(pathSep):]
+ }
+ const pkgSep = "."
+ if i := strings.Index(name, pkgSep); i != -1 {
+ name = name[i+len(pkgSep):]
+ }
+ }
+ io.WriteString(s, name)
+ }
+}
+
+// Frame returns the call frame infomation for the Call.
+func (c Call) Frame() runtime.Frame {
+ return c.frame
+}
+
+// PC returns the program counter for this call frame; multiple frames may
+// have the same PC value.
+//
+// Deprecated: Use Call.Frame instead.
+func (c Call) PC() uintptr {
+ return c.frame.PC
+}
+
+// CallStack records a sequence of function invocations from a goroutine
+// stack.
+type CallStack []Call
+
+// String implements fmt.Stinger. It is equivalent to fmt.Sprintf("%v", cs).
+func (cs CallStack) String() string {
+ return fmt.Sprint(cs)
+}
+
+var (
+ openBracketBytes = []byte("[")
+ closeBracketBytes = []byte("]")
+ spaceBytes = []byte(" ")
+)
+
+// MarshalText implements encoding.TextMarshaler. It formats the CallStack the
+// same as fmt.Sprintf("%v", cs).
+func (cs CallStack) MarshalText() ([]byte, error) {
+ buf := bytes.Buffer{}
+ buf.Write(openBracketBytes)
+ for i, pc := range cs {
+ if i > 0 {
+ buf.Write(spaceBytes)
+ }
+ fmt.Fprint(&buf, pc)
+ }
+ buf.Write(closeBracketBytes)
+ return buf.Bytes(), nil
+}
+
+// Format implements fmt.Formatter by printing the CallStack as square brackets
+// ([, ]) surrounding a space separated list of Calls each formatted with the
+// supplied verb and options.
+func (cs CallStack) Format(s fmt.State, verb rune) {
+ s.Write(openBracketBytes)
+ for i, pc := range cs {
+ if i > 0 {
+ s.Write(spaceBytes)
+ }
+ pc.Format(s, verb)
+ }
+ s.Write(closeBracketBytes)
+}
+
+// Trace returns a CallStack for the current goroutine with element 0
+// identifying the calling function.
+func Trace() CallStack {
+ var pcs [512]uintptr
+ n := runtime.Callers(1, pcs[:])
+
+ frames := runtime.CallersFrames(pcs[:n])
+ cs := make(CallStack, 0, n)
+
+ // Skip extra frame retrieved just to make sure the runtime.sigpanic
+ // special case is handled.
+ frame, more := frames.Next()
+
+ for more {
+ frame, more = frames.Next()
+ cs = append(cs, Call{frame: frame})
+ }
+
+ return cs
+}
+
+// TrimBelow returns a slice of the CallStack with all entries below c
+// removed.
+func (cs CallStack) TrimBelow(c Call) CallStack {
+ for len(cs) > 0 && cs[0] != c {
+ cs = cs[1:]
+ }
+ return cs
+}
+
+// TrimAbove returns a slice of the CallStack with all entries above c
+// removed.
+func (cs CallStack) TrimAbove(c Call) CallStack {
+ for len(cs) > 0 && cs[len(cs)-1] != c {
+ cs = cs[:len(cs)-1]
+ }
+ return cs
+}
+
+// pkgIndex returns the index that results in file[index:] being the path of
+// file relative to the compile time GOPATH, and file[:index] being the
+// $GOPATH/src/ portion of file. funcName must be the name of a function in
+// file as returned by runtime.Func.Name.
+func pkgIndex(file, funcName string) int {
+ // As of Go 1.6.2 there is no direct way to know the compile time GOPATH
+ // at runtime, but we can infer the number of path segments in the GOPATH.
+ // We note that runtime.Func.Name() returns the function name qualified by
+ // the import path, which does not include the GOPATH. Thus we can trim
+ // segments from the beginning of the file path until the number of path
+ // separators remaining is one more than the number of path separators in
+ // the function name. For example, given:
+ //
+ // GOPATH /home/user
+ // file /home/user/src/pkg/sub/file.go
+ // fn.Name() pkg/sub.Type.Method
+ //
+ // We want to produce:
+ //
+ // file[:idx] == /home/user/src/
+ // file[idx:] == pkg/sub/file.go
+ //
+ // From this we can easily see that fn.Name() has one less path separator
+ // than our desired result for file[idx:]. We count separators from the
+ // end of the file path until it finds two more than in the function name
+ // and then move one character forward to preserve the initial path
+ // segment without a leading separator.
+ const sep = "/"
+ i := len(file)
+ for n := strings.Count(funcName, sep) + 2; n > 0; n-- {
+ i = strings.LastIndex(file[:i], sep)
+ if i == -1 {
+ i = -len(sep)
+ break
+ }
+ }
+ // get back to 0 or trim the leading separator
+ return i + len(sep)
+}
+
+// pkgFilePath returns the frame's filepath relative to the compile-time GOPATH,
+// or its module path joined to its path relative to the module root.
+//
+// As of Go 1.11 there is no direct way to know the compile time GOPATH or
+// module paths at runtime, but we can piece together the desired information
+// from available information. We note that runtime.Frame.Function contains the
+// function name qualified by the package path, which includes the module path
+// but not the GOPATH. We can extract the package path from that and append the
+// last segments of the file path to arrive at the desired package qualified
+// file path. For example, given:
+//
+// GOPATH /home/user
+// import path pkg/sub
+// frame.File /home/user/src/pkg/sub/file.go
+// frame.Function pkg/sub.Type.Method
+// Desired return pkg/sub/file.go
+//
+// It appears that we simply need to trim ".Type.Method" from frame.Function and
+// append "/" + path.Base(file).
+//
+// But there are other wrinkles. Although it is idiomatic to do so, the internal
+// name of a package is not required to match the last segment of its import
+// path. In addition, the introduction of modules in Go 1.11 allows working
+// without a GOPATH. So we also must make these work right:
+//
+// GOPATH /home/user
+// import path pkg/go-sub
+// package name sub
+// frame.File /home/user/src/pkg/go-sub/file.go
+// frame.Function pkg/sub.Type.Method
+// Desired return pkg/go-sub/file.go
+//
+// Module path pkg/v2
+// import path pkg/v2/go-sub
+// package name sub
+// frame.File /home/user/cloned-pkg/go-sub/file.go
+// frame.Function pkg/v2/sub.Type.Method
+// Desired return pkg/v2/go-sub/file.go
+//
+// We can handle all of these situations by using the package path extracted
+// from frame.Function up to, but not including, the last segment as the prefix
+// and the last two segments of frame.File as the suffix of the returned path.
+// This preserves the existing behavior when working in a GOPATH without modules
+// and a semantically equivalent behavior when used in module aware project.
+func pkgFilePath(frame *runtime.Frame) string {
+ pre := pkgPrefix(frame.Function)
+ post := pathSuffix(frame.File)
+ if pre == "" {
+ return post
+ }
+ return pre + "/" + post
+}
+
+// pkgPrefix returns the import path of the function's package with the final
+// segment removed.
+func pkgPrefix(funcName string) string {
+ const pathSep = "/"
+ end := strings.LastIndex(funcName, pathSep)
+ if end == -1 {
+ return ""
+ }
+ return funcName[:end]
+}
+
+// pathSuffix returns the last two segments of path.
+func pathSuffix(path string) string {
+ const pathSep = "/"
+ lastSep := strings.LastIndex(path, pathSep)
+ if lastSep == -1 {
+ return path
+ }
+ return path[strings.LastIndex(path[:lastSep], pathSep)+1:]
+}
+
+var runtimePath string
+
+func init() {
+ var pcs [3]uintptr
+ runtime.Callers(0, pcs[:])
+ frames := runtime.CallersFrames(pcs[:])
+ frame, _ := frames.Next()
+ file := frame.File
+
+ idx := pkgIndex(frame.File, frame.Function)
+
+ runtimePath = file[:idx]
+ if runtime.GOOS == "windows" {
+ runtimePath = strings.ToLower(runtimePath)
+ }
+}
+
+func inGoroot(c Call) bool {
+ file := c.frame.File
+ if len(file) == 0 || file[0] == '?' {
+ return true
+ }
+ if runtime.GOOS == "windows" {
+ file = strings.ToLower(file)
+ }
+ return strings.HasPrefix(file, runtimePath) || strings.HasSuffix(file, "/_testmain.go")
+}
+
+// TrimRuntime returns a slice of the CallStack with the topmost entries from
+// the go runtime removed. It considers any calls originating from unknown
+// files, files under GOROOT, or _testmain.go as part of the runtime.
+func (cs CallStack) TrimRuntime() CallStack {
+ for len(cs) > 0 && inGoroot(cs[len(cs)-1]) {
+ cs = cs[:len(cs)-1]
+ }
+ return cs
+}