diff options
Diffstat (limited to 'vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/types_generate.go')
| -rw-r--r-- | vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/types_generate.go | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/types_generate.go b/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/types_generate.go new file mode 100644 index 000000000..dd1310942 --- /dev/null +++ b/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/types_generate.go @@ -0,0 +1,271 @@ +//+build ignore + +// types_generate.go is meant to run with go generate. It will use +// go/{importer,types} to track down all the RR struct types. Then for each type +// it will generate conversion tables (TypeToRR and TypeToString) and banal +// methods (len, Header, copy) based on the struct tags. The generated source is +// written to ztypes.go, and is meant to be checked into git. +package main + +import ( + "bytes" + "fmt" + "go/format" + "go/importer" + "go/types" + "log" + "os" + "strings" + "text/template" +) + +var skipLen = map[string]struct{}{ + "NSEC": {}, + "NSEC3": {}, + "OPT": {}, +} + +var packageHdr = ` +// *** DO NOT MODIFY *** +// AUTOGENERATED BY go generate from type_generate.go + +package dns + +import ( + "encoding/base64" + "net" +) + +` + +var TypeToRR = template.Must(template.New("TypeToRR").Parse(` +// TypeToRR is a map of constructors for each RR type. +var TypeToRR = map[uint16]func() RR{ +{{range .}}{{if ne . "RFC3597"}} Type{{.}}: func() RR { return new({{.}}) }, +{{end}}{{end}} } + +`)) + +var typeToString = template.Must(template.New("typeToString").Parse(` +// TypeToString is a map of strings for each RR type. +var TypeToString = map[uint16]string{ +{{range .}}{{if ne . "NSAPPTR"}} Type{{.}}: "{{.}}", +{{end}}{{end}} TypeNSAPPTR: "NSAP-PTR", +} + +`)) + +var headerFunc = template.Must(template.New("headerFunc").Parse(` +// Header() functions +{{range .}} func (rr *{{.}}) Header() *RR_Header { return &rr.Hdr } +{{end}} + +`)) + +// getTypeStruct will take a type and the package scope, and return the +// (innermost) struct if the type is considered a RR type (currently defined as +// those structs beginning with a RR_Header, could be redefined as implementing +// the RR interface). The bool return value indicates if embedded structs were +// resolved. +func getTypeStruct(t types.Type, scope *types.Scope) (*types.Struct, bool) { + st, ok := t.Underlying().(*types.Struct) + if !ok { + return nil, false + } + if st.Field(0).Type() == scope.Lookup("RR_Header").Type() { + return st, false + } + if st.Field(0).Anonymous() { + st, _ := getTypeStruct(st.Field(0).Type(), scope) + return st, true + } + return nil, false +} + +func main() { + // Import and type-check the package + pkg, err := importer.Default().Import("github.com/miekg/dns") + fatalIfErr(err) + scope := pkg.Scope() + + // Collect constants like TypeX + var numberedTypes []string + for _, name := range scope.Names() { + o := scope.Lookup(name) + if o == nil || !o.Exported() { + continue + } + b, ok := o.Type().(*types.Basic) + if !ok || b.Kind() != types.Uint16 { + continue + } + if !strings.HasPrefix(o.Name(), "Type") { + continue + } + name := strings.TrimPrefix(o.Name(), "Type") + if name == "PrivateRR" { + continue + } + numberedTypes = append(numberedTypes, name) + } + + // Collect actual types (*X) + var namedTypes []string + for _, name := range scope.Names() { + o := scope.Lookup(name) + if o == nil || !o.Exported() { + continue + } + if st, _ := getTypeStruct(o.Type(), scope); st == nil { + continue + } + if name == "PrivateRR" { + continue + } + + // Check if corresponding TypeX exists + if scope.Lookup("Type"+o.Name()) == nil && o.Name() != "RFC3597" { + log.Fatalf("Constant Type%s does not exist.", o.Name()) + } + + namedTypes = append(namedTypes, o.Name()) + } + + b := &bytes.Buffer{} + b.WriteString(packageHdr) + + // Generate TypeToRR + fatalIfErr(TypeToRR.Execute(b, namedTypes)) + + // Generate typeToString + fatalIfErr(typeToString.Execute(b, numberedTypes)) + + // Generate headerFunc + fatalIfErr(headerFunc.Execute(b, namedTypes)) + + // Generate len() + fmt.Fprint(b, "// len() functions\n") + for _, name := range namedTypes { + if _, ok := skipLen[name]; ok { + continue + } + o := scope.Lookup(name) + st, isEmbedded := getTypeStruct(o.Type(), scope) + if isEmbedded { + continue + } + fmt.Fprintf(b, "func (rr *%s) len() int {\n", name) + fmt.Fprintf(b, "l := rr.Hdr.len()\n") + for i := 1; i < st.NumFields(); i++ { + o := func(s string) { fmt.Fprintf(b, s, st.Field(i).Name()) } + + if _, ok := st.Field(i).Type().(*types.Slice); ok { + switch st.Tag(i) { + case `dns:"-"`: + // ignored + case `dns:"cdomain-name"`, `dns:"domain-name"`, `dns:"txt"`: + o("for _, x := range rr.%s { l += len(x) + 1 }\n") + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + continue + } + + switch { + case st.Tag(i) == `dns:"-"`: + // ignored + case st.Tag(i) == `dns:"cdomain-name"`, st.Tag(i) == `dns:"domain-name"`: + o("l += len(rr.%s) + 1\n") + case st.Tag(i) == `dns:"octet"`: + o("l += len(rr.%s)\n") + case strings.HasPrefix(st.Tag(i), `dns:"size-base64`): + fallthrough + case st.Tag(i) == `dns:"base64"`: + o("l += base64.StdEncoding.DecodedLen(len(rr.%s))\n") + case strings.HasPrefix(st.Tag(i), `dns:"size-hex`): + fallthrough + case st.Tag(i) == `dns:"hex"`: + o("l += len(rr.%s)/2 + 1\n") + case st.Tag(i) == `dns:"a"`: + o("l += net.IPv4len // %s\n") + case st.Tag(i) == `dns:"aaaa"`: + o("l += net.IPv6len // %s\n") + case st.Tag(i) == `dns:"txt"`: + o("for _, t := range rr.%s { l += len(t) + 1 }\n") + case st.Tag(i) == `dns:"uint48"`: + o("l += 6 // %s\n") + case st.Tag(i) == "": + switch st.Field(i).Type().(*types.Basic).Kind() { + case types.Uint8: + o("l++ // %s\n") + case types.Uint16: + o("l += 2 // %s\n") + case types.Uint32: + o("l += 4 // %s\n") + case types.Uint64: + o("l += 8 // %s\n") + case types.String: + o("l += len(rr.%s) + 1\n") + default: + log.Fatalln(name, st.Field(i).Name()) + } + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + } + fmt.Fprintf(b, "return l }\n") + } + + // Generate copy() + fmt.Fprint(b, "// copy() functions\n") + for _, name := range namedTypes { + o := scope.Lookup(name) + st, isEmbedded := getTypeStruct(o.Type(), scope) + if isEmbedded { + continue + } + fmt.Fprintf(b, "func (rr *%s) copy() RR {\n", name) + fields := []string{"*rr.Hdr.copyHeader()"} + for i := 1; i < st.NumFields(); i++ { + f := st.Field(i).Name() + if sl, ok := st.Field(i).Type().(*types.Slice); ok { + t := sl.Underlying().String() + t = strings.TrimPrefix(t, "[]") + if strings.Contains(t, ".") { + splits := strings.Split(t, ".") + t = splits[len(splits)-1] + } + fmt.Fprintf(b, "%s := make([]%s, len(rr.%s)); copy(%s, rr.%s)\n", + f, t, f, f, f) + fields = append(fields, f) + continue + } + if st.Field(i).Type().String() == "net.IP" { + fields = append(fields, "copyIP(rr."+f+")") + continue + } + fields = append(fields, "rr."+f) + } + fmt.Fprintf(b, "return &%s{%s}\n", name, strings.Join(fields, ",")) + fmt.Fprintf(b, "}\n") + } + + // gofmt + res, err := format.Source(b.Bytes()) + if err != nil { + b.WriteTo(os.Stderr) + log.Fatal(err) + } + + // write result + f, err := os.Create("ztypes.go") + fatalIfErr(err) + defer f.Close() + f.Write(res) +} + +func fatalIfErr(err error) { + if err != nil { + log.Fatal(err) + } +} |