Updates go-stack to v1.7.0.

Closes #10435

vendor/github.com/go-stack/stack/.travis.yml

-language: go
-sudo: false
-go:
-  - 1.2
-  - 1.3
-  - 1.4
-  - 1.5
-  - 1.6
-  - tip
-
-before_install:
-  - go get github.com/mattn/goveralls
-  - go get golang.org/x/tools/cmd/cover
-
-script:
-  - goveralls -service=travis-ci

vendor/github.com/go-stack/stack/LICENSE.md

-Copyright 2014 Chris Hines
+The MIT License (MIT)
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
+Copyright (c) 2014 Chris Hines
 
-   http://www.apache.org/licenses/LICENSE-2.0
+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:
 
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
+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.

vendor/github.com/go-stack/stack/stack.go

+// +build go1.7
+
 // Package stack implements utilities to capture, manipulate, and format call
 // stacks. It provides a simpler API than package runtime.
 //
@@ -21,29 +23,31 @@ import (
 
 // Call records a single function invocation from a goroutine stack.
 type Call struct {
-	fn *runtime.Func
-	pc uintptr
+	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 {
-	var pcs [2]uintptr
+	// 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()
 
-	var c Call
-
-	if n < 2 {
-		return c
-	}
-
-	c.pc = pcs[1]
-	if runtime.FuncForPC(pcs[0]) != sigpanic {
-		c.pc--
+	return Call{
+		frame: frame,
 	}
-	c.fn = runtime.FuncForPC(c.pc)
-	return c
 }
 
 // String implements fmt.Stinger. It is equivalent to fmt.Sprintf("%v", c).
@@ -54,9 +58,10 @@ func (c Call) String() string {
 // MarshalText implements encoding.TextMarshaler. It formats the Call the same
 // as fmt.Sprintf("%v", c).
 func (c Call) MarshalText() ([]byte, error) {
-	if c.fn == nil {
+	if c.frame == (runtime.Frame{}) {
 		return nil, ErrNoFunc
 	}
+
 	buf := bytes.Buffer{}
 	fmt.Fprint(&buf, c)
 	return buf.Bytes(), nil
@@ -71,6 +76,7 @@ var ErrNoFunc = errors.New("no call stack information")
 //    %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.
@@ -78,22 +84,23 @@ var ErrNoFunc = errors.New("no call stack information")
 //    %+s   path of source file relative to the compile time GOPATH
 //    %#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.fn == nil {
+	if c.frame == (runtime.Frame{}) {
 		fmt.Fprintf(s, "%%!%c(NOFUNC)", verb)
 		return
 	}
 
 	switch verb {
 	case 's', 'v':
-		file, line := c.fn.FileLine(c.pc)
+		file := c.frame.File
 		switch {
 		case s.Flag('#'):
 			// done
 		case s.Flag('+'):
-			file = file[pkgIndex(file, c.fn.Name()):]
+			file = file[pkgIndex(file, c.frame.Function):]
 		default:
 			const sep = "/"
 			if i := strings.LastIndex(file, sep); i != -1 {
@@ -103,16 +110,31 @@ func (c Call) Format(s fmt.State, verb rune) {
 		io.WriteString(s, file)
 		if verb == 'v' {
 			buf := [7]byte{':'}
-			s.Write(strconv.AppendInt(buf[:1], int64(line), 10))
+			s.Write(strconv.AppendInt(buf[:1], int64(c.frame.Line), 10))
 		}
 
 	case 'd':
-		_, line := c.fn.FileLine(c.pc)
 		buf := [6]byte{}
-		s.Write(strconv.AppendInt(buf[:0], int64(line), 10))
+		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.fn.Name()
+		name := c.frame.Function
 		if !s.Flag('+') {
 			const pathSep = "/"
 			if i := strings.LastIndex(name, pathSep); i != -1 {
@@ -127,35 +149,17 @@ func (c Call) Format(s fmt.State, verb rune) {
 	}
 }
 
+// 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.pc
-}
-
-// name returns the import path qualified name of the function containing the
-// call.
-func (c Call) name() string {
-	if c.fn == nil {
-		return "???"
-	}
-	return c.fn.Name()
-}
-
-func (c Call) file() string {
-	if c.fn == nil {
-		return "???"
-	}
-	file, _ := c.fn.FileLine(c.pc)
-	return file
-}
-
-func (c Call) line() int {
-	if c.fn == nil {
-		return 0
-	}
-	_, line := c.fn.FileLine(c.pc)
-	return line
+	return c.frame.PC
 }
 
 // CallStack records a sequence of function invocations from a goroutine
@@ -179,9 +183,6 @@ func (cs CallStack) MarshalText() ([]byte, error) {
 	buf := bytes.Buffer{}
 	buf.Write(openBracketBytes)
 	for i, pc := range cs {
-		if pc.fn == nil {
-			return nil, ErrNoFunc
-		}
 		if i > 0 {
 			buf.Write(spaceBytes)
 		}
@@ -205,49 +206,22 @@ func (cs CallStack) Format(s fmt.State, verb rune) {
 	s.Write(closeBracketBytes)
 }
 
-// findSigpanic intentionally executes faulting code to generate a stack trace
-// containing an entry for runtime.sigpanic.
-func findSigpanic() *runtime.Func {
-	var fn *runtime.Func
-	var p *int
-	func() int {
-		defer func() {
-			if p := recover(); p != nil {
-				var pcs [512]uintptr
-				n := runtime.Callers(2, pcs[:])
-				for _, pc := range pcs[:n] {
-					f := runtime.FuncForPC(pc)
-					if f.Name() == "runtime.sigpanic" {
-						fn = f
-						break
-					}
-				}
-			}
-		}()
-		// intentional nil pointer dereference to trigger sigpanic
-		return *p
-	}()
-	return fn
-}
-
-var sigpanic = findSigpanic()
-
 // 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(2, pcs[:])
-	cs := make([]Call, n)
+	n := runtime.Callers(1, pcs[:])
 
-	for i, pc := range pcs[:n] {
-		pcFix := pc
-		if i > 0 && cs[i-1].fn != sigpanic {
-			pcFix--
-		}
-		cs[i] = Call{
-			fn: runtime.FuncForPC(pcFix),
-			pc: pcFix,
-		}
+	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
@@ -256,7 +230,7 @@ func Trace() CallStack {
 // 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].pc != c.pc {
+	for len(cs) > 0 && cs[0] != c {
 		cs = cs[1:]
 	}
 	return cs
@@ -265,7 +239,7 @@ func (cs CallStack) TrimBelow(c Call) CallStack {
 // 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].pc != c.pc {
+	for len(cs) > 0 && cs[len(cs)-1] != c {
 		cs = cs[:len(cs)-1]
 	}
 	return cs
@@ -314,12 +288,13 @@ func pkgIndex(file, funcName string) int {
 var runtimePath string
 
 func init() {
-	var pcs [1]uintptr
+	var pcs [3]uintptr
 	runtime.Callers(0, pcs[:])
-	fn := runtime.FuncForPC(pcs[0])
-	file, _ := fn.FileLine(pcs[0])
+	frames := runtime.CallersFrames(pcs[:])
+	frame, _ := frames.Next()
+	file := frame.File
 
-	idx := pkgIndex(file, fn.Name())
+	idx := pkgIndex(frame.File, frame.Function)
 
 	runtimePath = file[:idx]
 	if runtime.GOOS == "windows" {
@@ -328,7 +303,7 @@ func init() {
 }
 
 func inGoroot(c Call) bool {
-	file := c.file()
+	file := c.frame.File
 	if len(file) == 0 || file[0] == '?' {
 		return true
 	}

vendor/vendor.json

@@ -415,6 +415,14 @@
 			"revisionTime": "2017-03-27T11:30:21Z"
 		},
 		{
+			"checksumSHA1": "luu+ud4XYZhlCoNnSAwCJlbh0Bg=",
+			"path": "github.com/go-stack/stack",
+			"revision": "259ab82a6cad3992b4e21ff5cac294ccb06474bc",
+			"revisionTime": "2017-11-12T03:14:02Z",
+			"version": "v1.7.0",
+			"versionExact": "v1.7.0"
+		},
+		{
 			"checksumSHA1": "HHB+Jna1wv0cXLxtCyOnQqFwvn4=",
 			"path": "github.com/go-xorm/builder",
 			"revision": "c6e604e9c7b7461715091e14ad0c242ec44c26e4",
@@ -486,7 +494,6 @@
 		},
 		{
 			"checksumSHA1": "y/A5iuvwjytQE2CqVuphQRXR2nI=",
-			"origin": "github.com/grafana/grafana/vendor/github.com/mattn/go-isatty",
 			"path": "github.com/mattn/go-isatty",
 			"revision": "a5cdd64afdee435007ee3e9f6ed4684af949d568",
 			"revisionTime": "2017-09-25T05:49:04Z"