Update deps

vendor/github.com/google/pprof/profile/profile.go

@@ -0,0 +1,805 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// 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
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// 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.
+
+// Package profile provides a representation of profile.proto and
+// methods to encode/decode profiles in this format.
+package profile
+
+import (
+	"bytes"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math"
+	"path/filepath"
+	"regexp"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+)
+
+// Profile is an in-memory representation of profile.proto.
+type Profile struct {
+	SampleType        []*ValueType
+	DefaultSampleType string
+	Sample            []*Sample
+	Mapping           []*Mapping
+	Location          []*Location
+	Function          []*Function
+	Comments          []string
+
+	DropFrames string
+	KeepFrames string
+
+	TimeNanos     int64
+	DurationNanos int64
+	PeriodType    *ValueType
+	Period        int64
+
+	// The following fields are modified during encoding and copying,
+	// so are protected by a Mutex.
+	encodeMu sync.Mutex
+
+	commentX           []int64
+	dropFramesX        int64
+	keepFramesX        int64
+	stringTable        []string
+	defaultSampleTypeX int64
+}
+
+// ValueType corresponds to Profile.ValueType
+type ValueType struct {
+	Type string // cpu, wall, inuse_space, etc
+	Unit string // seconds, nanoseconds, bytes, etc
+
+	typeX int64
+	unitX int64
+}
+
+// Sample corresponds to Profile.Sample
+type Sample struct {
+	Location []*Location
+	Value    []int64
+	Label    map[string][]string
+	NumLabel map[string][]int64
+	NumUnit  map[string][]string
+
+	locationIDX []uint64
+	labelX      []label
+}
+
+// label corresponds to Profile.Label
+type label struct {
+	keyX int64
+	// Exactly one of the two following values must be set
+	strX int64
+	numX int64 // Integer value for this label
+	// can be set if numX has value
+	unitX int64
+}
+
+// Mapping corresponds to Profile.Mapping
+type Mapping struct {
+	ID              uint64
+	Start           uint64
+	Limit           uint64
+	Offset          uint64
+	File            string
+	BuildID         string
+	HasFunctions    bool
+	HasFilenames    bool
+	HasLineNumbers  bool
+	HasInlineFrames bool
+
+	fileX    int64
+	buildIDX int64
+}
+
+// Location corresponds to Profile.Location
+type Location struct {
+	ID       uint64
+	Mapping  *Mapping
+	Address  uint64
+	Line     []Line
+	IsFolded bool
+
+	mappingIDX uint64
+}
+
+// Line corresponds to Profile.Line
+type Line struct {
+	Function *Function
+	Line     int64
+
+	functionIDX uint64
+}
+
+// Function corresponds to Profile.Function
+type Function struct {
+	ID         uint64
+	Name       string
+	SystemName string
+	Filename   string
+	StartLine  int64
+
+	nameX       int64
+	systemNameX int64
+	filenameX   int64
+}
+
+// Parse parses a profile and checks for its validity. The input
+// may be a gzip-compressed encoded protobuf or one of many legacy
+// profile formats which may be unsupported in the future.
+func Parse(r io.Reader) (*Profile, error) {
+	data, err := ioutil.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+	return ParseData(data)
+}
+
+// ParseData parses a profile from a buffer and checks for its
+// validity.
+func ParseData(data []byte) (*Profile, error) {
+	var p *Profile
+	var err error
+	if len(data) >= 2 && data[0] == 0x1f && data[1] == 0x8b {
+		gz, err := gzip.NewReader(bytes.NewBuffer(data))
+		if err == nil {
+			data, err = ioutil.ReadAll(gz)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("decompressing profile: %v", err)
+		}
+	}
+	if p, err = ParseUncompressed(data); err != nil && err != errNoData && err != errConcatProfile {
+		p, err = parseLegacy(data)
+	}
+
+	if err != nil {
+		return nil, fmt.Errorf("parsing profile: %v", err)
+	}
+
+	if err := p.CheckValid(); err != nil {
+		return nil, fmt.Errorf("malformed profile: %v", err)
+	}
+	return p, nil
+}
+
+var errUnrecognized = fmt.Errorf("unrecognized profile format")
+var errMalformed = fmt.Errorf("malformed profile format")
+var errNoData = fmt.Errorf("empty input file")
+var errConcatProfile = fmt.Errorf("concatenated profiles detected")
+
+func parseLegacy(data []byte) (*Profile, error) {
+	parsers := []func([]byte) (*Profile, error){
+		parseCPU,
+		parseHeap,
+		parseGoCount, // goroutine, threadcreate
+		parseThread,
+		parseContention,
+		parseJavaProfile,
+	}
+
+	for _, parser := range parsers {
+		p, err := parser(data)
+		if err == nil {
+			p.addLegacyFrameInfo()
+			return p, nil
+		}
+		if err != errUnrecognized {
+			return nil, err
+		}
+	}
+	return nil, errUnrecognized
+}
+
+// ParseUncompressed parses an uncompressed protobuf into a profile.
+func ParseUncompressed(data []byte) (*Profile, error) {
+	if len(data) == 0 {
+		return nil, errNoData
+	}
+	p := &Profile{}
+	if err := unmarshal(data, p); err != nil {
+		return nil, err
+	}
+
+	if err := p.postDecode(); err != nil {
+		return nil, err
+	}
+
+	return p, nil
+}
+
+var libRx = regexp.MustCompile(`([.]so$|[.]so[._][0-9]+)`)
+
+// massageMappings applies heuristic-based changes to the profile
+// mappings to account for quirks of some environments.
+func (p *Profile) massageMappings() {
+	// Merge adjacent regions with matching names, checking that the offsets match
+	if len(p.Mapping) > 1 {
+		mappings := []*Mapping{p.Mapping[0]}
+		for _, m := range p.Mapping[1:] {
+			lm := mappings[len(mappings)-1]
+			if adjacent(lm, m) {
+				lm.Limit = m.Limit
+				if m.File != "" {
+					lm.File = m.File
+				}
+				if m.BuildID != "" {
+					lm.BuildID = m.BuildID
+				}
+				p.updateLocationMapping(m, lm)
+				continue
+			}
+			mappings = append(mappings, m)
+		}
+		p.Mapping = mappings
+	}
+
+	// Use heuristics to identify main binary and move it to the top of the list of mappings
+	for i, m := range p.Mapping {
+		file := strings.TrimSpace(strings.Replace(m.File, "(deleted)", "", -1))
+		if len(file) == 0 {
+			continue
+		}
+		if len(libRx.FindStringSubmatch(file)) > 0 {
+			continue
+		}
+		if file[0] == '[' {
+			continue
+		}
+		// Swap what we guess is main to position 0.
+		p.Mapping[0], p.Mapping[i] = p.Mapping[i], p.Mapping[0]
+		break
+	}
+
+	// Keep the mapping IDs neatly sorted
+	for i, m := range p.Mapping {
+		m.ID = uint64(i + 1)
+	}
+}
+
+// adjacent returns whether two mapping entries represent the same
+// mapping that has been split into two. Check that their addresses are adjacent,
+// and if the offsets match, if they are available.
+func adjacent(m1, m2 *Mapping) bool {
+	if m1.File != "" && m2.File != "" {
+		if m1.File != m2.File {
+			return false
+		}
+	}
+	if m1.BuildID != "" && m2.BuildID != "" {
+		if m1.BuildID != m2.BuildID {
+			return false
+		}
+	}
+	if m1.Limit != m2.Start {
+		return false
+	}
+	if m1.Offset != 0 && m2.Offset != 0 {
+		offset := m1.Offset + (m1.Limit - m1.Start)
+		if offset != m2.Offset {
+			return false
+		}
+	}
+	return true
+}
+
+func (p *Profile) updateLocationMapping(from, to *Mapping) {
+	for _, l := range p.Location {
+		if l.Mapping == from {
+			l.Mapping = to
+		}
+	}
+}
+
+func serialize(p *Profile) []byte {
+	p.encodeMu.Lock()
+	p.preEncode()
+	b := marshal(p)
+	p.encodeMu.Unlock()
+	return b
+}
+
+// Write writes the profile as a gzip-compressed marshaled protobuf.
+func (p *Profile) Write(w io.Writer) error {
+	zw := gzip.NewWriter(w)
+	defer zw.Close()
+	_, err := zw.Write(serialize(p))
+	return err
+}
+
+// WriteUncompressed writes the profile as a marshaled protobuf.
+func (p *Profile) WriteUncompressed(w io.Writer) error {
+	_, err := w.Write(serialize(p))
+	return err
+}
+
+// CheckValid tests whether the profile is valid. Checks include, but are
+// not limited to:
+//   - len(Profile.Sample[n].value) == len(Profile.value_unit)
+//   - Sample.id has a corresponding Profile.Location
+func (p *Profile) CheckValid() error {
+	// Check that sample values are consistent
+	sampleLen := len(p.SampleType)
+	if sampleLen == 0 && len(p.Sample) != 0 {
+		return fmt.Errorf("missing sample type information")
+	}
+	for _, s := range p.Sample {
+		if s == nil {
+			return fmt.Errorf("profile has nil sample")
+		}
+		if len(s.Value) != sampleLen {
+			return fmt.Errorf("mismatch: sample has %d values vs. %d types", len(s.Value), len(p.SampleType))
+		}
+		for _, l := range s.Location {
+			if l == nil {
+				return fmt.Errorf("sample has nil location")
+			}
+		}
+	}
+
+	// Check that all mappings/locations/functions are in the tables
+	// Check that there are no duplicate ids
+	mappings := make(map[uint64]*Mapping, len(p.Mapping))
+	for _, m := range p.Mapping {
+		if m == nil {
+			return fmt.Errorf("profile has nil mapping")
+		}
+		if m.ID == 0 {
+			return fmt.Errorf("found mapping with reserved ID=0")
+		}
+		if mappings[m.ID] != nil {
+			return fmt.Errorf("multiple mappings with same id: %d", m.ID)
+		}
+		mappings[m.ID] = m
+	}
+	functions := make(map[uint64]*Function, len(p.Function))
+	for _, f := range p.Function {
+		if f == nil {
+			return fmt.Errorf("profile has nil function")
+		}
+		if f.ID == 0 {
+			return fmt.Errorf("found function with reserved ID=0")
+		}
+		if functions[f.ID] != nil {
+			return fmt.Errorf("multiple functions with same id: %d", f.ID)
+		}
+		functions[f.ID] = f
+	}
+	locations := make(map[uint64]*Location, len(p.Location))
+	for _, l := range p.Location {
+		if l == nil {
+			return fmt.Errorf("profile has nil location")
+		}
+		if l.ID == 0 {
+			return fmt.Errorf("found location with reserved id=0")
+		}
+		if locations[l.ID] != nil {
+			return fmt.Errorf("multiple locations with same id: %d", l.ID)
+		}
+		locations[l.ID] = l
+		if m := l.Mapping; m != nil {
+			if m.ID == 0 || mappings[m.ID] != m {
+				return fmt.Errorf("inconsistent mapping %p: %d", m, m.ID)
+			}
+		}
+		for _, ln := range l.Line {
+			f := ln.Function
+			if f == nil {
+				return fmt.Errorf("location id: %d has a line with nil function", l.ID)
+			}
+			if f.ID == 0 || functions[f.ID] != f {
+				return fmt.Errorf("inconsistent function %p: %d", f, f.ID)
+			}
+		}
+	}
+	return nil
+}
+
+// Aggregate merges the locations in the profile into equivalence
+// classes preserving the request attributes. It also updates the
+// samples to point to the merged locations.
+func (p *Profile) Aggregate(inlineFrame, function, filename, linenumber, address bool) error {
+	for _, m := range p.Mapping {
+		m.HasInlineFrames = m.HasInlineFrames && inlineFrame
+		m.HasFunctions = m.HasFunctions && function
+		m.HasFilenames = m.HasFilenames && filename
+		m.HasLineNumbers = m.HasLineNumbers && linenumber
+	}
+
+	// Aggregate functions
+	if !function || !filename {
+		for _, f := range p.Function {
+			if !function {
+				f.Name = ""
+				f.SystemName = ""
+			}
+			if !filename {
+				f.Filename = ""
+			}
+		}
+	}
+
+	// Aggregate locations
+	if !inlineFrame || !address || !linenumber {
+		for _, l := range p.Location {
+			if !inlineFrame && len(l.Line) > 1 {
+				l.Line = l.Line[len(l.Line)-1:]
+			}
+			if !linenumber {
+				for i := range l.Line {
+					l.Line[i].Line = 0
+				}
+			}
+			if !address {
+				l.Address = 0
+			}
+		}
+	}
+
+	return p.CheckValid()
+}
+
+// NumLabelUnits returns a map of numeric label keys to the units
+// associated with those keys and a map of those keys to any units
+// that were encountered but not used.
+// Unit for a given key is the first encountered unit for that key. If multiple
+// units are encountered for values paired with a particular key, then the first
+// unit encountered is used and all other units are returned in sorted order
+// in map of ignored units.
+// If no units are encountered for a particular key, the unit is then inferred
+// based on the key.
+func (p *Profile) NumLabelUnits() (map[string]string, map[string][]string) {
+	numLabelUnits := map[string]string{}
+	ignoredUnits := map[string]map[string]bool{}
+	encounteredKeys := map[string]bool{}
+
+	// Determine units based on numeric tags for each sample.
+	for _, s := range p.Sample {
+		for k := range s.NumLabel {
+			encounteredKeys[k] = true
+			for _, unit := range s.NumUnit[k] {
+				if unit == "" {
+					continue
+				}
+				if wantUnit, ok := numLabelUnits[k]; !ok {
+					numLabelUnits[k] = unit
+				} else if wantUnit != unit {
+					if v, ok := ignoredUnits[k]; ok {
+						v[unit] = true
+					} else {
+						ignoredUnits[k] = map[string]bool{unit: true}
+					}
+				}
+			}
+		}
+	}
+	// Infer units for keys without any units associated with
+	// numeric tag values.
+	for key := range encounteredKeys {
+		unit := numLabelUnits[key]
+		if unit == "" {
+			switch key {
+			case "alignment", "request":
+				numLabelUnits[key] = "bytes"
+			default:
+				numLabelUnits[key] = key
+			}
+		}
+	}
+
+	// Copy ignored units into more readable format
+	unitsIgnored := make(map[string][]string, len(ignoredUnits))
+	for key, values := range ignoredUnits {
+		units := make([]string, len(values))
+		i := 0
+		for unit := range values {
+			units[i] = unit
+			i++
+		}
+		sort.Strings(units)
+		unitsIgnored[key] = units
+	}
+
+	return numLabelUnits, unitsIgnored
+}
+
+// String dumps a text representation of a profile. Intended mainly
+// for debugging purposes.
+func (p *Profile) String() string {
+	ss := make([]string, 0, len(p.Comments)+len(p.Sample)+len(p.Mapping)+len(p.Location))
+	for _, c := range p.Comments {
+		ss = append(ss, "Comment: "+c)
+	}
+	if pt := p.PeriodType; pt != nil {
+		ss = append(ss, fmt.Sprintf("PeriodType: %s %s", pt.Type, pt.Unit))
+	}
+	ss = append(ss, fmt.Sprintf("Period: %d", p.Period))
+	if p.TimeNanos != 0 {
+		ss = append(ss, fmt.Sprintf("Time: %v", time.Unix(0, p.TimeNanos)))
+	}
+	if p.DurationNanos != 0 {
+		ss = append(ss, fmt.Sprintf("Duration: %.4v", time.Duration(p.DurationNanos)))
+	}
+
+	ss = append(ss, "Samples:")
+	var sh1 string
+	for _, s := range p.SampleType {
+		dflt := ""
+		if s.Type == p.DefaultSampleType {
+			dflt = "[dflt]"
+		}
+		sh1 = sh1 + fmt.Sprintf("%s/%s%s ", s.Type, s.Unit, dflt)
+	}
+	ss = append(ss, strings.TrimSpace(sh1))
+	for _, s := range p.Sample {
+		ss = append(ss, s.string())
+	}
+
+	ss = append(ss, "Locations")
+	for _, l := range p.Location {
+		ss = append(ss, l.string())
+	}
+
+	ss = append(ss, "Mappings")
+	for _, m := range p.Mapping {
+		ss = append(ss, m.string())
+	}
+
+	return strings.Join(ss, "\n") + "\n"
+}
+
+// string dumps a text representation of a mapping. Intended mainly
+// for debugging purposes.
+func (m *Mapping) string() string {
+	bits := ""
+	if m.HasFunctions {
+		bits = bits + "[FN]"
+	}
+	if m.HasFilenames {
+		bits = bits + "[FL]"
+	}
+	if m.HasLineNumbers {
+		bits = bits + "[LN]"
+	}
+	if m.HasInlineFrames {
+		bits = bits + "[IN]"
+	}
+	return fmt.Sprintf("%d: %#x/%#x/%#x %s %s %s",
+		m.ID,
+		m.Start, m.Limit, m.Offset,
+		m.File,
+		m.BuildID,
+		bits)
+}
+
+// string dumps a text representation of a location. Intended mainly
+// for debugging purposes.
+func (l *Location) string() string {
+	ss := []string{}
+	locStr := fmt.Sprintf("%6d: %#x ", l.ID, l.Address)
+	if m := l.Mapping; m != nil {
+		locStr = locStr + fmt.Sprintf("M=%d ", m.ID)
+	}
+	if l.IsFolded {
+		locStr = locStr + "[F] "
+	}
+	if len(l.Line) == 0 {
+		ss = append(ss, locStr)
+	}
+	for li := range l.Line {
+		lnStr := "??"
+		if fn := l.Line[li].Function; fn != nil {
+			lnStr = fmt.Sprintf("%s %s:%d s=%d",
+				fn.Name,
+				fn.Filename,
+				l.Line[li].Line,
+				fn.StartLine)
+			if fn.Name != fn.SystemName {
+				lnStr = lnStr + "(" + fn.SystemName + ")"
+			}
+		}
+		ss = append(ss, locStr+lnStr)
+		// Do not print location details past the first line
+		locStr = "             "
+	}
+	return strings.Join(ss, "\n")
+}
+
+// string dumps a text representation of a sample. Intended mainly
+// for debugging purposes.
+func (s *Sample) string() string {
+	ss := []string{}
+	var sv string
+	for _, v := range s.Value {
+		sv = fmt.Sprintf("%s %10d", sv, v)
+	}
+	sv = sv + ": "
+	for _, l := range s.Location {
+		sv = sv + fmt.Sprintf("%d ", l.ID)
+	}
+	ss = append(ss, sv)
+	const labelHeader = "                "
+	if len(s.Label) > 0 {
+		ss = append(ss, labelHeader+labelsToString(s.Label))
+	}
+	if len(s.NumLabel) > 0 {
+		ss = append(ss, labelHeader+numLabelsToString(s.NumLabel, s.NumUnit))
+	}
+	return strings.Join(ss, "\n")
+}
+
+// labelsToString returns a string representation of a
+// map representing labels.
+func labelsToString(labels map[string][]string) string {
+	ls := []string{}
+	for k, v := range labels {
+		ls = append(ls, fmt.Sprintf("%s:%v", k, v))
+	}
+	sort.Strings(ls)
+	return strings.Join(ls, " ")
+}
+
+// numLabelsToString returns a string representation of a map
+// representing numeric labels.
+func numLabelsToString(numLabels map[string][]int64, numUnits map[string][]string) string {
+	ls := []string{}
+	for k, v := range numLabels {
+		units := numUnits[k]
+		var labelString string
+		if len(units) == len(v) {
+			values := make([]string, len(v))
+			for i, vv := range v {
+				values[i] = fmt.Sprintf("%d %s", vv, units[i])
+			}
+			labelString = fmt.Sprintf("%s:%v", k, values)
+		} else {
+			labelString = fmt.Sprintf("%s:%v", k, v)
+		}
+		ls = append(ls, labelString)
+	}
+	sort.Strings(ls)
+	return strings.Join(ls, " ")
+}
+
+// SetLabel sets the specified key to the specified value for all samples in the
+// profile.
+func (p *Profile) SetLabel(key string, value []string) {
+	for _, sample := range p.Sample {
+		if sample.Label == nil {
+			sample.Label = map[string][]string{key: value}
+		} else {
+			sample.Label[key] = value
+		}
+	}
+}
+
+// RemoveLabel removes all labels associated with the specified key for all
+// samples in the profile.
+func (p *Profile) RemoveLabel(key string) {
+	for _, sample := range p.Sample {
+		delete(sample.Label, key)
+	}
+}
+
+// HasLabel returns true if a sample has a label with indicated key and value.
+func (s *Sample) HasLabel(key, value string) bool {
+	for _, v := range s.Label[key] {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+// DiffBaseSample returns true if a sample belongs to the diff base and false
+// otherwise.
+func (s *Sample) DiffBaseSample() bool {
+	return s.HasLabel("pprof::base", "true")
+}
+
+// Scale multiplies all sample values in a profile by a constant and keeps
+// only samples that have at least one non-zero value.
+func (p *Profile) Scale(ratio float64) {
+	if ratio == 1 {
+		return
+	}
+	ratios := make([]float64, len(p.SampleType))
+	for i := range p.SampleType {
+		ratios[i] = ratio
+	}
+	p.ScaleN(ratios)
+}
+
+// ScaleN multiplies each sample values in a sample by a different amount
+// and keeps only samples that have at least one non-zero value.
+func (p *Profile) ScaleN(ratios []float64) error {
+	if len(p.SampleType) != len(ratios) {
+		return fmt.Errorf("mismatched scale ratios, got %d, want %d", len(ratios), len(p.SampleType))
+	}
+	allOnes := true
+	for _, r := range ratios {
+		if r != 1 {
+			allOnes = false
+			break
+		}
+	}
+	if allOnes {
+		return nil
+	}
+	fillIdx := 0
+	for _, s := range p.Sample {
+		keepSample := false
+		for i, v := range s.Value {
+			if ratios[i] != 1 {
+				val := int64(math.Round(float64(v) * ratios[i]))
+				s.Value[i] = val
+				keepSample = keepSample || val != 0
+			}
+		}
+		if keepSample {
+			p.Sample[fillIdx] = s
+			fillIdx++
+		}
+	}
+	p.Sample = p.Sample[:fillIdx]
+	return nil
+}
+
+// HasFunctions determines if all locations in this profile have
+// symbolized function information.
+func (p *Profile) HasFunctions() bool {
+	for _, l := range p.Location {
+		if l.Mapping != nil && !l.Mapping.HasFunctions {
+			return false
+		}
+	}
+	return true
+}
+
+// HasFileLines determines if all locations in this profile have
+// symbolized file and line number information.
+func (p *Profile) HasFileLines() bool {
+	for _, l := range p.Location {
+		if l.Mapping != nil && (!l.Mapping.HasFilenames || !l.Mapping.HasLineNumbers) {
+			return false
+		}
+	}
+	return true
+}
+
+// Unsymbolizable returns true if a mapping points to a binary for which
+// locations can't be symbolized in principle, at least now. Examples are
+// "[vdso]", [vsyscall]" and some others, see the code.
+func (m *Mapping) Unsymbolizable() bool {
+	name := filepath.Base(m.File)
+	return strings.HasPrefix(name, "[") || strings.HasPrefix(name, "linux-vdso") || strings.HasPrefix(m.File, "/dev/dri/")
+}
+
+// Copy makes a fully independent copy of a profile.
+func (p *Profile) Copy() *Profile {
+	pp := &Profile{}
+	if err := unmarshal(serialize(p), pp); err != nil {
+		panic(err)
+	}
+	if err := pp.postDecode(); err != nil {
+		panic(err)
+	}
+
+	return pp
+}