Source: encode.go in package github.com/google/pprof/profile

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

import (
	"errors"
	"sort"
)

func (p *Profile) decoder() []decoder {
	return profileDecoder
}

preEncode populates the unexported fields to be used by encode (with suffix X) from the corresponding exported fields. The exported fields are cleared up to facilitate testing.

func (p *Profile) preEncode() {
	strings := make(map[string]int)
	addString(strings, "")

	for _, st := range p.SampleType {
		st.typeX = addString(strings, st.Type)
		st.unitX = addString(strings, st.Unit)
	}

	for _, s := range p.Sample {
		s.labelX = nil
		var keys []string
		for k := range s.Label {
			keys = append(keys, k)
		}
		sort.Strings(keys)
		for _, k := range keys {
			vs := s.Label[k]
			for _, v := range vs {
				s.labelX = append(s.labelX,
					label{
						keyX: addString(strings, k),
						strX: addString(strings, v),
					},
				)
			}
		}
		var numKeys []string
		for k := range s.NumLabel {
			numKeys = append(numKeys, k)
		}
		sort.Strings(numKeys)
		for _, k := range numKeys {
			keyX := addString(strings, k)
			vs := s.NumLabel[k]
			units := s.NumUnit[k]
			for i, v := range vs {
				var unitX int64
				if len(units) != 0 {
					unitX = addString(strings, units[i])
				}
				s.labelX = append(s.labelX,
					label{
						keyX:  keyX,
						numX:  v,
						unitX: unitX,
					},
				)
			}
		}
		s.locationIDX = make([]uint64, len(s.Location))
		for i, loc := range s.Location {
			s.locationIDX[i] = loc.ID
		}
	}

	for _, m := range p.Mapping {
		m.fileX = addString(strings, m.File)
		m.buildIDX = addString(strings, m.BuildID)
	}

	for _, l := range p.Location {
		for i, ln := range l.Line {
			if ln.Function != nil {
				l.Line[i].functionIDX = ln.Function.ID
			} else {
				l.Line[i].functionIDX = 0
			}
		}
		if l.Mapping != nil {
			l.mappingIDX = l.Mapping.ID
		} else {
			l.mappingIDX = 0
		}
	}
	for _, f := range p.Function {
		f.nameX = addString(strings, f.Name)
		f.systemNameX = addString(strings, f.SystemName)
		f.filenameX = addString(strings, f.Filename)
	}

	p.dropFramesX = addString(strings, p.DropFrames)
	p.keepFramesX = addString(strings, p.KeepFrames)

	if pt := p.PeriodType; pt != nil {
		pt.typeX = addString(strings, pt.Type)
		pt.unitX = addString(strings, pt.Unit)
	}

	p.commentX = nil
	for _, c := range p.Comments {
		p.commentX = append(p.commentX, addString(strings, c))
	}

	p.defaultSampleTypeX = addString(strings, p.DefaultSampleType)

	p.stringTable = make([]string, len(strings))
	for s, i := range strings {
		p.stringTable[i] = s
	}
}

func (p *Profile) encode(b *buffer) {
	for _, x := range p.SampleType {
		encodeMessage(b, 1, x)
	}
	for _, x := range p.Sample {
		encodeMessage(b, 2, x)
	}
	for _, x := range p.Mapping {
		encodeMessage(b, 3, x)
	}
	for _, x := range p.Location {
		encodeMessage(b, 4, x)
	}
	for _, x := range p.Function {
		encodeMessage(b, 5, x)
	}
	encodeStrings(b, 6, p.stringTable)
	encodeInt64Opt(b, 7, p.dropFramesX)
	encodeInt64Opt(b, 8, p.keepFramesX)
	encodeInt64Opt(b, 9, p.TimeNanos)
	encodeInt64Opt(b, 10, p.DurationNanos)
	if pt := p.PeriodType; pt != nil && (pt.typeX != 0 || pt.unitX != 0) {
		encodeMessage(b, 11, p.PeriodType)
	}
	encodeInt64Opt(b, 12, p.Period)
	encodeInt64s(b, 13, p.commentX)
	encodeInt64(b, 14, p.defaultSampleTypeX)
}

var profileDecoder = []decoder{

repeated ValueType sample_type = 1

	func(b *buffer, m message) error {
		x := new(ValueType)
		pp := m.(*Profile)
		pp.SampleType = append(pp.SampleType, x)
		return decodeMessage(b, x)

repeated Sample sample = 2

	func(b *buffer, m message) error {
		x := new(Sample)
		pp := m.(*Profile)
		pp.Sample = append(pp.Sample, x)
		return decodeMessage(b, x)

repeated Mapping mapping = 3

	func(b *buffer, m message) error {
		x := new(Mapping)
		pp := m.(*Profile)
		pp.Mapping = append(pp.Mapping, x)
		return decodeMessage(b, x)

repeated Location location = 4

	func(b *buffer, m message) error {
		x := new(Location)
		x.Line = make([]Line, 0, 8) // Pre-allocate Line buffer
		pp := m.(*Profile)
		pp.Location = append(pp.Location, x)
		err := decodeMessage(b, x)
		var tmp []Line
		x.Line = append(tmp, x.Line...) // Shrink to allocated size
		return err

repeated Function function = 5

	func(b *buffer, m message) error {
		x := new(Function)
		pp := m.(*Profile)
		pp.Function = append(pp.Function, x)
		return decodeMessage(b, x)

repeated string string_table = 6

	func(b *buffer, m message) error {
		err := decodeStrings(b, &m.(*Profile).stringTable)
		if err != nil {
			return err
		}
		if m.(*Profile).stringTable[0] != "" {
			return errors.New("string_table[0] must be ''")
		}
		return nil

int64 drop_frames = 7

int64 keep_frames = 8

int64 time_nanos = 9

	func(b *buffer, m message) error {
		if m.(*Profile).TimeNanos != 0 {
			return errConcatProfile
		}
		return decodeInt64(b, &m.(*Profile).TimeNanos)

int64 duration_nanos = 10

ValueType period_type = 11

	func(b *buffer, m message) error {
		x := new(ValueType)
		pp := m.(*Profile)
		pp.PeriodType = x
		return decodeMessage(b, x)

int64 period = 12

repeated int64 comment = 13

int64 defaultSampleType = 14

	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Profile).defaultSampleTypeX) },
}

postDecode takes the unexported fields populated by decode (with suffix X) and populates the corresponding exported fields. The unexported fields are cleared up to facilitate testing.

func (p *Profile) postDecode() error {
	var err error
	mappings := make(map[uint64]*Mapping, len(p.Mapping))
	mappingIds := make([]*Mapping, len(p.Mapping)+1)
	for _, m := range p.Mapping {
		m.File, err = getString(p.stringTable, &m.fileX, err)
		m.BuildID, err = getString(p.stringTable, &m.buildIDX, err)
		if m.ID < uint64(len(mappingIds)) {
			mappingIds[m.ID] = m
		} else {
			mappings[m.ID] = m
		}
	}

	functions := make(map[uint64]*Function, len(p.Function))
	functionIds := make([]*Function, len(p.Function)+1)
	for _, f := range p.Function {
		f.Name, err = getString(p.stringTable, &f.nameX, err)
		f.SystemName, err = getString(p.stringTable, &f.systemNameX, err)
		f.Filename, err = getString(p.stringTable, &f.filenameX, err)
		if f.ID < uint64(len(functionIds)) {
			functionIds[f.ID] = f
		} else {
			functions[f.ID] = f
		}
	}

	locations := make(map[uint64]*Location, len(p.Location))
	locationIds := make([]*Location, len(p.Location)+1)
	for _, l := range p.Location {
		if id := l.mappingIDX; id < uint64(len(mappingIds)) {
			l.Mapping = mappingIds[id]
		} else {
			l.Mapping = mappings[id]
		}
		l.mappingIDX = 0
		for i, ln := range l.Line {
			if id := ln.functionIDX; id != 0 {
				l.Line[i].functionIDX = 0
				if id < uint64(len(functionIds)) {
					l.Line[i].Function = functionIds[id]
				} else {
					l.Line[i].Function = functions[id]
				}
			}
		}
		if l.ID < uint64(len(locationIds)) {
			locationIds[l.ID] = l
		} else {
			locations[l.ID] = l
		}
	}

	for _, st := range p.SampleType {
		st.Type, err = getString(p.stringTable, &st.typeX, err)
		st.Unit, err = getString(p.stringTable, &st.unitX, err)
	}

	for _, s := range p.Sample {
		labels := make(map[string][]string, len(s.labelX))
		numLabels := make(map[string][]int64, len(s.labelX))
		numUnits := make(map[string][]string, len(s.labelX))
		for _, l := range s.labelX {
			var key, value string
			key, err = getString(p.stringTable, &l.keyX, err)
			if l.strX != 0 {
				value, err = getString(p.stringTable, &l.strX, err)
				labels[key] = append(labels[key], value)
			} else if l.numX != 0 {
				numValues := numLabels[key]
				units := numUnits[key]
				if l.unitX != 0 {
					var unit string
					unit, err = getString(p.stringTable, &l.unitX, err)
					units = padStringArray(units, len(numValues))
					numUnits[key] = append(units, unit)
				}
				numLabels[key] = append(numLabels[key], l.numX)
			}
		}
		if len(labels) > 0 {
			s.Label = labels
		}
		if len(numLabels) > 0 {
			s.NumLabel = numLabels
			for key, units := range numUnits {
				if len(units) > 0 {
					numUnits[key] = padStringArray(units, len(numLabels[key]))
				}
			}
			s.NumUnit = numUnits
		}
		s.Location = make([]*Location, len(s.locationIDX))
		for i, lid := range s.locationIDX {
			if lid < uint64(len(locationIds)) {
				s.Location[i] = locationIds[lid]
			} else {
				s.Location[i] = locations[lid]
			}
		}
		s.locationIDX = nil
	}

	p.DropFrames, err = getString(p.stringTable, &p.dropFramesX, err)
	p.KeepFrames, err = getString(p.stringTable, &p.keepFramesX, err)

	if pt := p.PeriodType; pt == nil {
		p.PeriodType = &ValueType{}
	}

	if pt := p.PeriodType; pt != nil {
		pt.Type, err = getString(p.stringTable, &pt.typeX, err)
		pt.Unit, err = getString(p.stringTable, &pt.unitX, err)
	}

	for _, i := range p.commentX {
		var c string
		c, err = getString(p.stringTable, &i, err)
		p.Comments = append(p.Comments, c)
	}

	p.commentX = nil
	p.DefaultSampleType, err = getString(p.stringTable, &p.defaultSampleTypeX, err)
	p.stringTable = nil
	return err
}

padStringArray pads arr with enough empty strings to make arr length l when arr's length is less than l.

func padStringArray(arr []string, l int) []string {
	if l <= len(arr) {
		return arr
	}
	return append(arr, make([]string, l-len(arr))...)
}

func (p *ValueType) decoder() []decoder {
	return valueTypeDecoder
}

func (p *ValueType) encode(b *buffer) {
	encodeInt64Opt(b, 1, p.typeX)
	encodeInt64Opt(b, 2, p.unitX)
}

var valueTypeDecoder = []decoder{

optional int64 type = 1

optional int64 unit = 2

	func(b *buffer, m message) error { return decodeInt64(b, &m.(*ValueType).unitX) },
}

func (p *Sample) decoder() []decoder {
	return sampleDecoder
}

func (p *Sample) encode(b *buffer) {
	encodeUint64s(b, 1, p.locationIDX)
	encodeInt64s(b, 2, p.Value)
	for _, x := range p.labelX {
		encodeMessage(b, 3, x)
	}
}

var sampleDecoder = []decoder{

repeated uint64 location = 1

repeated int64 value = 2

repeated Label label = 3

	func(b *buffer, m message) error {
		s := m.(*Sample)
		n := len(s.labelX)
		s.labelX = append(s.labelX, label{})
		return decodeMessage(b, &s.labelX[n])
	},
}

func (p label) decoder() []decoder {
	return labelDecoder
}

func (p label) encode(b *buffer) {
	encodeInt64Opt(b, 1, p.keyX)
	encodeInt64Opt(b, 2, p.strX)
	encodeInt64Opt(b, 3, p.numX)
	encodeInt64Opt(b, 4, p.unitX)
}

var labelDecoder = []decoder{

optional int64 key = 1

optional int64 str = 2

optional int64 num = 3

optional int64 num = 4

	func(b *buffer, m message) error { return decodeInt64(b, &m.(*label).unitX) },
}

func (p *Mapping) decoder() []decoder {
	return mappingDecoder
}

func (p *Mapping) encode(b *buffer) {
	encodeUint64Opt(b, 1, p.ID)
	encodeUint64Opt(b, 2, p.Start)
	encodeUint64Opt(b, 3, p.Limit)
	encodeUint64Opt(b, 4, p.Offset)
	encodeInt64Opt(b, 5, p.fileX)
	encodeInt64Opt(b, 6, p.buildIDX)
	encodeBoolOpt(b, 7, p.HasFunctions)
	encodeBoolOpt(b, 8, p.HasFilenames)
	encodeBoolOpt(b, 9, p.HasLineNumbers)
	encodeBoolOpt(b, 10, p.HasInlineFrames)
}

var mappingDecoder = []decoder{
	nil, // 0
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Mapping).ID) },            // optional uint64 id = 1
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Mapping).Start) },         // optional uint64 memory_offset = 2
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Mapping).Limit) },         // optional uint64 memory_limit = 3
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Mapping).Offset) },        // optional uint64 file_offset = 4
	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Mapping).fileX) },          // optional int64 filename = 5
	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Mapping).buildIDX) },       // optional int64 build_id = 6
	func(b *buffer, m message) error { return decodeBool(b, &m.(*Mapping).HasFunctions) },    // optional bool has_functions = 7
	func(b *buffer, m message) error { return decodeBool(b, &m.(*Mapping).HasFilenames) },    // optional bool has_filenames = 8
	func(b *buffer, m message) error { return decodeBool(b, &m.(*Mapping).HasLineNumbers) },  // optional bool has_line_numbers = 9
	func(b *buffer, m message) error { return decodeBool(b, &m.(*Mapping).HasInlineFrames) }, // optional bool has_inline_frames = 10
}

func (p *Location) decoder() []decoder {
	return locationDecoder
}

func (p *Location) encode(b *buffer) {
	encodeUint64Opt(b, 1, p.ID)
	encodeUint64Opt(b, 2, p.mappingIDX)
	encodeUint64Opt(b, 3, p.Address)
	for i := range p.Line {
		encodeMessage(b, 4, &p.Line[i])
	}
	encodeBoolOpt(b, 5, p.IsFolded)
}

var locationDecoder = []decoder{
	nil, // 0
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Location).ID) },         // optional uint64 id = 1;
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Location).mappingIDX) }, // optional uint64 mapping_id = 2;
	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Location).Address) },    // optional uint64 address = 3;
	func(b *buffer, m message) error { // repeated Line line = 4
		pp := m.(*Location)
		n := len(pp.Line)
		pp.Line = append(pp.Line, Line{})
		return decodeMessage(b, &pp.Line[n])
	},
	func(b *buffer, m message) error { return decodeBool(b, &m.(*Location).IsFolded) }, // optional bool is_folded = 5;
}

func (p *Line) decoder() []decoder {
	return lineDecoder
}

func (p *Line) encode(b *buffer) {
	encodeUint64Opt(b, 1, p.functionIDX)
	encodeInt64Opt(b, 2, p.Line)
}

var lineDecoder = []decoder{

optional uint64 function_id = 1

optional int64 line = 2

	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Line).Line) },
}

func (p *Function) decoder() []decoder {
	return functionDecoder
}

func (p *Function) encode(b *buffer) {
	encodeUint64Opt(b, 1, p.ID)
	encodeInt64Opt(b, 2, p.nameX)
	encodeInt64Opt(b, 3, p.systemNameX)
	encodeInt64Opt(b, 4, p.filenameX)
	encodeInt64Opt(b, 5, p.StartLine)
}

var functionDecoder = []decoder{

optional uint64 id = 1

optional int64 function_name = 2

optional int64 function_system_name = 3

repeated int64 filename = 4

optional int64 start_line = 5

	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Function).StartLine) },
}

func addString(strings map[string]int, s string) int64 {
	i, ok := strings[s]
	if !ok {
		i = len(strings)
		strings[s] = i
	}
	return int64(i)
}

func getString(strings []string, strng *int64, err error) (string, error) {
	if err != nil {
		return "", err
	}
	s := int(*strng)
	if s < 0 || s >= len(strings) {
		return "", errMalformed
	}
	*strng = 0
	return strings[s], nil