syncthing/vendor/github.com/calmh/xdr/cmd/genxdr/main.go
Jakob Borg 65aaa607ab Use Go 1.5 vendoring instead of Godeps
Change made by:

- running "gvt fetch" on each of the packages mentioned in
  Godeps/Godeps.json
- `rm -rf Godeps`
- tweaking the build scripts to not mention Godeps
- tweaking the build scripts to test `./lib/...`, `./cmd/...` explicitly
  (to avoid testing vendor)
- tweaking the build scripts to not juggle GOPATH for Godeps and instead
  set GO15VENDOREXPERIMENT.

This also results in some updated packages at the same time I bet.

Building with Go 1.3 and 1.4 still *works* but won't use our vendored
dependencies - the user needs to have the actual packages in their
GOPATH then, which they'll get with a normal "go get". Building with Go
1.6+ will get our vendored dependencies by default even when not using
our build script, which is nice.

By doing this we gain some freedom in that we can pick and choose
manually what to include in vendor, as it's not based on just dependency
analysis of our own code. This is also a risk as we might pick up
dependencies we are unaware of, as the build may work locally with those
packages present in GOPATH. On the other hand the build server will
detect this as it has no packages in it's GOPATH beyond what is included
in the repo.

Recommended tool to manage dependencies is github.com/FiloSottile/gvt.
2016-03-05 21:21:24 +01:00

587 lines
13 KiB
Go

// Copyright (C) 2014 Jakob Borg. All rights reserved. Use of this source code
// is governed by an MIT-style license that can be found in the LICENSE file.
package main
import (
"bytes"
"flag"
"fmt"
"go/ast"
"go/format"
"go/parser"
"go/token"
"io"
"log"
"os"
"regexp"
"strconv"
"strings"
"text/template"
)
type fieldInfo struct {
Name string
IsBasic bool // handled by one the native Read/WriteUint64 etc functions
IsSlice bool // field is a slice of FieldType
FieldType string // original type of field, i.e. "int"
Encoder string // the encoder name, i.e. "Uint64" for Read/WriteUint64
Convert string // what to convert to when encoding, i.e. "uint64"
Max int // max size for slices and strings
Submax int // max size for strings inside slices
}
type structInfo struct {
Name string
Fields []fieldInfo
}
func (i structInfo) SizeExpr() string {
var xdrSizes = map[string]int{
"int8": 4,
"uint8": 4,
"int16": 4,
"uint16": 4,
"int32": 4,
"uint32": 4,
"int64": 8,
"uint64": 8,
"int": 8,
"bool": 4,
}
var terms []string
nl := ""
for _, f := range i.Fields {
if size := xdrSizes[f.FieldType]; size > 0 {
if f.IsSlice {
terms = append(terms, nl+"4+len(o."+f.Name+")*"+strconv.Itoa(size))
} else {
terms = append(terms, strconv.Itoa(size))
}
} else {
switch f.FieldType {
case "string", "[]byte":
if f.IsSlice {
terms = append(terms, nl+"4+xdr.SizeOfSlice(o."+f.Name+")")
} else {
terms = append(terms, nl+"4+len(o."+f.Name+")+xdr.Padding(len(o."+f.Name+"))")
}
default:
if f.IsSlice {
terms = append(terms, nl+"4+xdr.SizeOfSlice(o."+f.Name+")")
} else {
terms = append(terms, nl+"o."+f.Name+".XDRSize()")
}
}
}
nl = "\n"
}
return strings.Join(terms, "+")
}
var headerData = `// ************************************************************
// This file is automatically generated by genxdr. Do not edit.
// ************************************************************
package {{.Package}}
import (
"github.com/calmh/xdr"
)
`
var encoderData = `
func (o {{.Name}}) XDRSize() int {
return {{.SizeExpr}}
}//+n
func (o {{.Name}}) MarshalXDR() ([]byte, error) {
buf:= make([]byte, o.XDRSize())
m := &xdr.Marshaller{Data: buf}
return buf, o.MarshalXDRInto(m)
}//+n
func (o {{.Name}}) MustMarshalXDR() []byte {
bs, err := o.MarshalXDR()
if err != nil {
panic(err)
}
return bs
}//+n
func (o {{.Name}}) MarshalXDRInto(m *xdr.Marshaller) error {
{{range $fi := .Fields}}
{{if $fi.IsSlice}}
{{template "marshalSlice" $fi}}
{{else}}
{{template "marshalValue" $fi}}
{{end}}
{{end}}
return m.Error
}//+n
{{define "marshalValue"}}
{{if ne .Convert ""}}
m.Marshal{{.Encoder}}({{.Convert}}(o.{{.Name}}))
{{else if .IsBasic}}
{{if ge .Max 1}}
if l := len(o.{{.Name}}); l > {{.Max}} {
return xdr.ElementSizeExceeded("{{.Name}}", l, {{.Max}})
}
{{end}}
m.Marshal{{.Encoder}}(o.{{.Name}})
{{else}}
if err := o.{{.Name}}.MarshalXDRInto(m); err != nil {
return err
}
{{end}}
{{end}}
{{define "marshalSlice"}}
{{if ge .Max 1}}
if l := len(o.{{.Name}}); l > {{.Max}} {
return xdr.ElementSizeExceeded("{{.Name}}", l, {{.Max}})
}
{{end}}
m.MarshalUint32(uint32(len(o.{{.Name}})))
for i := range o.{{.Name}} {
{{if ne .Convert ""}}
m.Marshal{{.Encoder}}({{.Convert}}(o.{{.Name}}[i]))
{{else if .IsBasic}}
m.Marshal{{.Encoder}}(o.{{.Name}}[i])
{{else}}
if err := o.{{.Name}}[i].MarshalXDRInto(m); err != nil {
return err
}
{{end}}
}
{{end}}
func (o *{{.Name}}) UnmarshalXDR(bs []byte) error {
u := &xdr.Unmarshaller{Data: bs}
return o.UnmarshalXDRFrom(u)
}
func (o *{{.Name}}) UnmarshalXDRFrom(u *xdr.Unmarshaller) error {
{{range $fi := .Fields}}
{{if $fi.IsSlice}}
{{template "unmarshalSlice" $fi}}
{{else}}
{{template "unmarshalValue" $fi}}
{{end}}
{{end}}
return u.Error
}//+n
{{define "unmarshalValue"}}
{{if ne .Convert ""}}
o.{{.Name}} = {{.FieldType}}(u.Unmarshal{{.Encoder}}())
{{else if .IsBasic}}
{{if ge .Max 1}}
o.{{.Name}} = u.Unmarshal{{.Encoder}}Max({{.Max}})
{{else}}
o.{{.Name}} = u.Unmarshal{{.Encoder}}()
{{end}}
{{else}}
(&o.{{.Name}}).UnmarshalXDRFrom(u)
{{end}}
{{end}}
{{define "unmarshalSlice"}}
_{{.Name}}Size := int(u.UnmarshalUint32())
if _{{.Name}}Size < 0 {
return xdr.ElementSizeExceeded("{{.Name}}", _{{.Name}}Size, {{.Max}})
} else if _{{.Name}}Size == 0 {
o.{{.Name}} = nil
} else {
{{if ge .Max 1}}
if _{{.Name}}Size > {{.Max}} {
return xdr.ElementSizeExceeded("{{.Name}}", _{{.Name}}Size, {{.Max}})
}
{{end}}
if _{{.Name}}Size <= len(o.{{.Name}}) {
{{if eq .FieldType "string"}}
for i := _{{.Name}}Size; i < len(o.{{.Name}}); i++ { o.{{.Name}}[i] = "" }
{{end}}
{{if eq .FieldType "[]byte"}}
for i := _{{.Name}}Size; i < len(o.{{.Name}}); i++ { o.{{.Name}}[i] = nil }
{{end}}
o.{{.Name}} = o.{{.Name}}[:_{{.Name}}Size]
} else {
o.{{.Name}} = make([]{{.FieldType}}, _{{.Name}}Size)
}
for i := range o.{{.Name}} {
{{if ne .Convert ""}}
o.{{.Name}}[i] = {{.FieldType}}(u.Unmarshal{{.Encoder}}())
{{else if .IsBasic}}
{{if ge .Submax 1}}
o.{{.Name}}[i] = u.Unmarshal{{.Encoder}}Max({{.Submax}})
{{else}}
o.{{.Name}}[i] = u.Unmarshal{{.Encoder}}()
{{end}}
{{else}}
(&o.{{.Name}}[i]).UnmarshalXDRFrom(u)
{{end}}
}
}
{{end}}
`
var (
encodeTpl = template.Must(template.New("encoder").Parse(encoderData))
headerTpl = template.Must(template.New("header").Parse(headerData))
)
var emptyTypeTpl = template.Must(template.New("encoder").Parse(`
func (o {{.Name}}) XDRSize() int {
return 0
}
func (o {{.Name}}) MarshalXDR() ([]byte, error) {
return nil, nil
}//+n
func (o {{.Name}}) MustMarshalXDR() []byte {
return nil
}//+n
func (o {{.Name}}) MarshalXDRInto(m *xdr.Marshaller) error {
return nil
}//+n
func (o *{{.Name}}) UnmarshalXDR(bs []byte) error {
return nil
}//+n
func (o *{{.Name}}) UnmarshalXDRFrom(u *xdr.Unmarshaller) error {
return nil
}//+n
`))
var maxRe = regexp.MustCompile(`(?:\Wmax:)(\d+)(?:\s*,\s*(\d+))?`)
type typeSet struct {
Type string
Encoder string
}
var xdrEncoders = map[string]typeSet{
"int8": typeSet{"uint8", "Uint8"},
"uint8": typeSet{"", "Uint8"},
"int16": typeSet{"uint16", "Uint16"},
"uint16": typeSet{"", "Uint16"},
"int32": typeSet{"uint32", "Uint32"},
"uint32": typeSet{"", "Uint32"},
"int64": typeSet{"uint64", "Uint64"},
"uint64": typeSet{"", "Uint64"},
"int": typeSet{"uint64", "Uint64"},
"string": typeSet{"", "String"},
"[]byte": typeSet{"", "Bytes"},
"bool": typeSet{"", "Bool"},
}
func handleStruct(t *ast.StructType) []fieldInfo {
var fs []fieldInfo
for _, sf := range t.Fields.List {
if len(sf.Names) == 0 {
// We don't handle anonymous fields
continue
}
fn := sf.Names[0].Name
var max1, max2 int
if sf.Comment != nil {
c := sf.Comment.List[0].Text
m := maxRe.FindStringSubmatch(c)
if len(m) >= 2 {
max1, _ = strconv.Atoi(m[1])
}
if len(m) >= 3 {
max2, _ = strconv.Atoi(m[2])
}
if strings.Contains(c, "noencode") {
continue
}
}
var f fieldInfo
switch ft := sf.Type.(type) {
case *ast.Ident:
tn := ft.Name
if enc, ok := xdrEncoders[tn]; ok {
f = fieldInfo{
Name: fn,
IsBasic: true,
FieldType: tn,
Encoder: enc.Encoder,
Convert: enc.Type,
Max: max1,
Submax: max2,
}
} else {
f = fieldInfo{
Name: fn,
IsBasic: false,
FieldType: tn,
Max: max1,
Submax: max2,
}
}
case *ast.ArrayType:
if ft.Len != nil {
// We don't handle arrays
continue
}
tn := ft.Elt.(*ast.Ident).Name
if enc, ok := xdrEncoders["[]"+tn]; ok {
f = fieldInfo{
Name: fn,
IsBasic: true,
FieldType: "[]" + tn,
Encoder: enc.Encoder,
Convert: enc.Type,
Max: max1,
Submax: max2,
}
} else if enc, ok := xdrEncoders[tn]; ok {
f = fieldInfo{
Name: fn,
IsBasic: true,
IsSlice: true,
FieldType: tn,
Encoder: enc.Encoder,
Convert: enc.Type,
Max: max1,
Submax: max2,
}
} else {
f = fieldInfo{
Name: fn,
IsSlice: true,
FieldType: tn,
Max: max1,
Submax: max2,
}
}
case *ast.SelectorExpr:
f = fieldInfo{
Name: fn,
FieldType: ft.Sel.Name,
Max: max1,
Submax: max2,
}
}
fs = append(fs, f)
}
return fs
}
func generateCode(output io.Writer, s structInfo) {
var buf bytes.Buffer
var err error
if len(s.Fields) == 0 {
// This is an empty type. We can create a quite simple codec for it.
err = emptyTypeTpl.Execute(&buf, s)
} else {
// Generate with the default template.
err = encodeTpl.Execute(&buf, s)
}
if err != nil {
panic(err)
}
bs := regexp.MustCompile(`(\s*\n)+`).ReplaceAll(buf.Bytes(), []byte("\n"))
bs = bytes.Replace(bs, []byte("//+n"), []byte("\n"), -1)
output.Write(bs)
}
func uncamelize(s string) string {
return regexp.MustCompile("[a-z][A-Z]").ReplaceAllStringFunc(s, func(camel string) string {
return camel[:1] + " " + camel[1:]
})
}
func generateDiagram(output io.Writer, s structInfo) {
sn := s.Name
fs := s.Fields
fmt.Fprintln(output, sn+" Structure:")
if len(fs) == 0 {
fmt.Fprintln(output, "(contains no fields)")
fmt.Fprintln(output)
fmt.Fprintln(output)
return
}
fmt.Fprintln(output)
fmt.Fprintln(output, " 0 1 2 3")
fmt.Fprintln(output, " 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1")
line := "+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+"
fmt.Fprintln(output, line)
for _, f := range fs {
tn := f.FieldType
name := uncamelize(f.Name)
suffix := ""
if f.IsSlice {
fmt.Fprintf(output, "| %s |\n", center("Number of "+name, 61))
fmt.Fprintln(output, line)
suffix = " (n items)"
fmt.Fprintf(output, "/ %s /\n", center("", 61))
}
switch tn {
case "bool":
fmt.Fprintf(output, "| %s |V|\n", center(name+" (V=0 or 1)", 59))
case "int16", "uint16":
fmt.Fprintf(output, "| %s | %s |\n", center("16 zero bits", 29), center(name, 29))
case "int8", "uint8":
fmt.Fprintf(output, "| %s | %s |\n", center("24 zero bits", 45), center(name, 13))
case "int32", "uint32":
fmt.Fprintf(output, "| %s |\n", center(name+suffix, 61))
case "int64", "uint64":
fmt.Fprintf(output, "| %-61s |\n", "")
fmt.Fprintf(output, "+ %s +\n", center(name+" (64 bits)", 61))
fmt.Fprintf(output, "| %-61s |\n", "")
case "string", "[]byte":
fmt.Fprintf(output, "/ %61s /\n", "")
fmt.Fprintf(output, "\\ %s \\\n", center(name+" (length + padded data)", 61))
fmt.Fprintf(output, "/ %61s /\n", "")
default:
if f.IsSlice {
tn = "Zero or more " + tn + " Structures"
fmt.Fprintf(output, "\\ %s \\\n", center(tn, 61))
} else {
tn = tn + " Structure"
fmt.Fprintf(output, "/ %s /\n", center("", 61))
fmt.Fprintf(output, "\\ %s \\\n", center(tn, 61))
fmt.Fprintf(output, "/ %s /\n", center("", 61))
}
}
if f.IsSlice {
fmt.Fprintf(output, "/ %s /\n", center("", 61))
}
fmt.Fprintln(output, line)
}
fmt.Fprintln(output)
fmt.Fprintln(output)
}
func generateXdr(output io.Writer, s structInfo) {
sn := s.Name
fs := s.Fields
fmt.Fprintf(output, "struct %s {\n", sn)
for _, f := range fs {
tn := f.FieldType
fn := f.Name
suf := ""
l := ""
if f.Max > 0 {
l = strconv.Itoa(f.Max)
}
if f.IsSlice {
suf = "<" + l + ">"
}
switch tn {
case "int8", "int16", "int32":
fmt.Fprintf(output, "\tint %s%s;\n", fn, suf)
case "uint8", "uint16", "uint32":
fmt.Fprintf(output, "\tunsigned int %s%s;\n", fn, suf)
case "int64":
fmt.Fprintf(output, "\thyper %s%s;\n", fn, suf)
case "uint64":
fmt.Fprintf(output, "\tunsigned hyper %s%s;\n", fn, suf)
case "string":
fmt.Fprintf(output, "\tstring %s<%s>;\n", fn, l)
case "[]byte":
fmt.Fprintf(output, "\topaque %s<%s>;\n", fn, l)
default:
fmt.Fprintf(output, "\t%s %s%s;\n", tn, fn, suf)
}
}
fmt.Fprintln(output, "}")
fmt.Fprintln(output)
}
func center(s string, w int) string {
w -= len(s)
l := w / 2
r := l
if l+r < w {
r++
}
return strings.Repeat(" ", l) + s + strings.Repeat(" ", r)
}
func inspector(structs *[]structInfo) func(ast.Node) bool {
return func(n ast.Node) bool {
switch n := n.(type) {
case *ast.TypeSpec:
switch t := n.Type.(type) {
case *ast.StructType:
name := n.Name.Name
fs := handleStruct(t)
*structs = append(*structs, structInfo{name, fs})
}
return false
default:
return true
}
}
}
func main() {
outputFile := flag.String("o", "", "Output file, blank for stdout")
flag.Parse()
fname := flag.Arg(0)
fset := token.NewFileSet()
f, err := parser.ParseFile(fset, fname, nil, parser.ParseComments)
if err != nil {
log.Fatal(err)
}
var structs []structInfo
i := inspector(&structs)
ast.Inspect(f, i)
buf := new(bytes.Buffer)
headerTpl.Execute(buf, map[string]string{"Package": f.Name.Name})
for _, s := range structs {
fmt.Fprintf(buf, "\n/*\n\n")
generateDiagram(buf, s)
generateXdr(buf, s)
fmt.Fprintf(buf, "*/\n")
generateCode(buf, s)
}
bs, err := format.Source(buf.Bytes())
if err != nil {
log.Print(buf.String())
log.Fatal(err)
}
var output io.Writer = os.Stdout
if *outputFile != "" {
fd, err := os.Create(*outputFile)
if err != nil {
log.Fatal(err)
}
output = fd
}
output.Write(bs)
}