From ec7f81f4bc11c6f8203ec1d3055c9a09a244ff43 Mon Sep 17 00:00:00 2001
From: Péter Szilágyi <peterke@gmail.com>
Date: Mon, 20 Feb 2017 17:39:36 +0200
Subject: log, vendor: vendor in log15 inline into our codebase

---
 vendor/github.com/go-stack/stack/stack.go | 349 ++++++++++++++++++++++++++++++
 1 file changed, 349 insertions(+)
 create mode 100644 vendor/github.com/go-stack/stack/stack.go

(limited to 'vendor/github.com/go-stack/stack/stack.go')

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 000000000..a614eeebf
--- /dev/null
+++ b/vendor/github.com/go-stack/stack/stack.go
@@ -0,0 +1,349 @@
+// 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 {
+	fn *runtime.Func
+	pc uintptr
+}
+
+// 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
+	n := runtime.Callers(skip+1, pcs[:])
+
+	var c Call
+
+	if n < 2 {
+		return c
+	}
+
+	c.pc = pcs[1]
+	if runtime.FuncForPC(pcs[0]) != sigpanic {
+		c.pc--
+	}
+	c.fn = runtime.FuncForPC(c.pc)
+	return c
+}
+
+// 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.fn == nil {
+		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
+//    %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
+//    %#s   full path of source file
+//    %+n   import path qualified function name
+//    %+v   equivalent to %+s:%d
+//    %#v   equivalent to %#s:%d
+func (c Call) Format(s fmt.State, verb rune) {
+	if c.fn == nil {
+		fmt.Fprintf(s, "%%!%c(NOFUNC)", verb)
+		return
+	}
+
+	switch verb {
+	case 's', 'v':
+		file, line := c.fn.FileLine(c.pc)
+		switch {
+		case s.Flag('#'):
+			// done
+		case s.Flag('+'):
+			file = file[pkgIndex(file, c.fn.Name()):]
+		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(line), 10))
+		}
+
+	case 'd':
+		_, line := c.fn.FileLine(c.pc)
+		buf := [6]byte{}
+		s.Write(strconv.AppendInt(buf[:0], int64(line), 10))
+
+	case 'n':
+		name := c.fn.Name()
+		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)
+	}
+}
+
+// PC returns the program counter for this call frame; multiple frames may
+// have the same PC value.
+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
+}
+
+// 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 pc.fn == nil {
+			return nil, ErrNoFunc
+		}
+		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)
+}
+
+// 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)
+
+	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,
+		}
+	}
+
+	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].pc != c.pc {
+		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].pc != c.pc {
+		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)
+}
+
+var runtimePath string
+
+func init() {
+	var pcs [1]uintptr
+	runtime.Callers(0, pcs[:])
+	fn := runtime.FuncForPC(pcs[0])
+	file, _ := fn.FileLine(pcs[0])
+
+	idx := pkgIndex(file, fn.Name())
+
+	runtimePath = file[:idx]
+	if runtime.GOOS == "windows" {
+		runtimePath = strings.ToLower(runtimePath)
+	}
+}
+
+func inGoroot(c Call) bool {
+	file := c.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
+}
-- 
cgit