node_exporter/vendor/github.com/kolo/xmlrpc/decoder.go

450 lines
8.9 KiB
Go

package xmlrpc
import (
"bytes"
"encoding/xml"
"errors"
"fmt"
"io"
"reflect"
"strconv"
"strings"
"time"
)
const iso8601 = "20060102T15:04:05"
var (
// CharsetReader is a function to generate reader which converts a non UTF-8
// charset into UTF-8.
CharsetReader func(string, io.Reader) (io.Reader, error)
invalidXmlError = errors.New("invalid xml")
)
type TypeMismatchError string
func (e TypeMismatchError) Error() string { return string(e) }
type decoder struct {
*xml.Decoder
}
func unmarshal(data []byte, v interface{}) (err error) {
dec := &decoder{xml.NewDecoder(bytes.NewBuffer(data))}
if CharsetReader != nil {
dec.CharsetReader = CharsetReader
}
var tok xml.Token
for {
if tok, err = dec.Token(); err != nil {
return err
}
if t, ok := tok.(xml.StartElement); ok {
if t.Name.Local == "value" {
val := reflect.ValueOf(v)
if val.Kind() != reflect.Ptr {
return errors.New("non-pointer value passed to unmarshal")
}
if err = dec.decodeValue(val.Elem()); err != nil {
return err
}
break
}
}
}
// read until end of document
err = dec.Skip()
if err != nil && err != io.EOF {
return err
}
return nil
}
func (dec *decoder) decodeValue(val reflect.Value) error {
var tok xml.Token
var err error
if val.Kind() == reflect.Ptr {
if val.IsNil() {
val.Set(reflect.New(val.Type().Elem()))
}
val = val.Elem()
}
var typeName string
for {
if tok, err = dec.Token(); err != nil {
return err
}
if t, ok := tok.(xml.EndElement); ok {
if t.Name.Local == "value" {
return nil
} else {
return invalidXmlError
}
}
if t, ok := tok.(xml.StartElement); ok {
typeName = t.Name.Local
break
}
// Treat value data without type identifier as string
if t, ok := tok.(xml.CharData); ok {
if value := strings.TrimSpace(string(t)); value != "" {
if err = checkType(val, reflect.String); err != nil {
return err
}
val.SetString(value)
return nil
}
}
}
switch typeName {
case "struct":
ismap := false
pmap := val
valType := val.Type()
if err = checkType(val, reflect.Struct); err != nil {
if checkType(val, reflect.Map) == nil {
if valType.Key().Kind() != reflect.String {
return fmt.Errorf("only maps with string key type can be unmarshalled")
}
ismap = true
} else if checkType(val, reflect.Interface) == nil && val.IsNil() {
var dummy map[string]interface{}
pmap = reflect.New(reflect.TypeOf(dummy)).Elem()
valType = pmap.Type()
ismap = true
} else {
return err
}
}
var fields map[string]reflect.Value
if !ismap {
fields = make(map[string]reflect.Value)
for i := 0; i < valType.NumField(); i++ {
field := valType.Field(i)
fieldVal := val.FieldByName(field.Name)
if fieldVal.CanSet() {
if fn := field.Tag.Get("xmlrpc"); fn != "" {
fields[fn] = fieldVal
} else {
fields[field.Name] = fieldVal
}
}
}
} else {
// Create initial empty map
pmap.Set(reflect.MakeMap(valType))
}
// Process struct members.
StructLoop:
for {
if tok, err = dec.Token(); err != nil {
return err
}
switch t := tok.(type) {
case xml.StartElement:
if t.Name.Local != "member" {
return invalidXmlError
}
tagName, fieldName, err := dec.readTag()
if err != nil {
return err
}
if tagName != "name" {
return invalidXmlError
}
var fv reflect.Value
ok := true
if !ismap {
fv, ok = fields[string(fieldName)]
} else {
fv = reflect.New(valType.Elem())
}
if ok {
for {
if tok, err = dec.Token(); err != nil {
return err
}
if t, ok := tok.(xml.StartElement); ok && t.Name.Local == "value" {
if err = dec.decodeValue(fv); err != nil {
return err
}
// </value>
if err = dec.Skip(); err != nil {
return err
}
break
}
}
}
// </member>
if err = dec.Skip(); err != nil {
return err
}
if ismap {
pmap.SetMapIndex(reflect.ValueOf(string(fieldName)), reflect.Indirect(fv))
val.Set(pmap)
}
case xml.EndElement:
break StructLoop
}
}
case "array":
pslice := val
if checkType(val, reflect.Interface) == nil && val.IsNil() {
var dummy []interface{}
pslice = reflect.New(reflect.TypeOf(dummy)).Elem()
} else if err = checkType(val, reflect.Slice); err != nil {
return err
}
ArrayLoop:
for {
if tok, err = dec.Token(); err != nil {
return err
}
switch t := tok.(type) {
case xml.StartElement:
if t.Name.Local != "data" {
return invalidXmlError
}
slice := reflect.MakeSlice(pslice.Type(), 0, 0)
DataLoop:
for {
if tok, err = dec.Token(); err != nil {
return err
}
switch tt := tok.(type) {
case xml.StartElement:
if tt.Name.Local != "value" {
return invalidXmlError
}
v := reflect.New(pslice.Type().Elem())
if err = dec.decodeValue(v); err != nil {
return err
}
slice = reflect.Append(slice, v.Elem())
// </value>
if err = dec.Skip(); err != nil {
return err
}
case xml.EndElement:
pslice.Set(slice)
val.Set(pslice)
break DataLoop
}
}
case xml.EndElement:
break ArrayLoop
}
}
default:
if tok, err = dec.Token(); err != nil {
return err
}
var data []byte
switch t := tok.(type) {
case xml.EndElement:
return nil
case xml.CharData:
data = []byte(t.Copy())
default:
return invalidXmlError
}
switch typeName {
case "int", "i4", "i8":
if checkType(val, reflect.Interface) == nil && val.IsNil() {
i, err := strconv.ParseInt(string(data), 10, 64)
if err != nil {
return err
}
pi := reflect.New(reflect.TypeOf(i)).Elem()
pi.SetInt(i)
val.Set(pi)
} else if err = checkType(val, reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64); err != nil {
return err
} else {
i, err := strconv.ParseInt(string(data), 10, val.Type().Bits())
if err != nil {
return err
}
val.SetInt(i)
}
case "string", "base64":
str := string(data)
if checkType(val, reflect.Interface) == nil && val.IsNil() {
pstr := reflect.New(reflect.TypeOf(str)).Elem()
pstr.SetString(str)
val.Set(pstr)
} else if err = checkType(val, reflect.String); err != nil {
return err
} else {
val.SetString(str)
}
case "dateTime.iso8601":
t, err := time.Parse(iso8601, string(data))
if err != nil {
return err
}
if checkType(val, reflect.Interface) == nil && val.IsNil() {
ptime := reflect.New(reflect.TypeOf(t)).Elem()
ptime.Set(reflect.ValueOf(t))
val.Set(ptime)
} else if _, ok := val.Interface().(time.Time); !ok {
return TypeMismatchError(fmt.Sprintf("error: type mismatch error - can't decode %v to time", val.Kind()))
} else {
val.Set(reflect.ValueOf(t))
}
case "boolean":
v, err := strconv.ParseBool(string(data))
if err != nil {
return err
}
if checkType(val, reflect.Interface) == nil && val.IsNil() {
pv := reflect.New(reflect.TypeOf(v)).Elem()
pv.SetBool(v)
val.Set(pv)
} else if err = checkType(val, reflect.Bool); err != nil {
return err
} else {
val.SetBool(v)
}
case "double":
if checkType(val, reflect.Interface) == nil && val.IsNil() {
i, err := strconv.ParseFloat(string(data), 64)
if err != nil {
return err
}
pdouble := reflect.New(reflect.TypeOf(i)).Elem()
pdouble.SetFloat(i)
val.Set(pdouble)
} else if err = checkType(val, reflect.Float32, reflect.Float64); err != nil {
return err
} else {
i, err := strconv.ParseFloat(string(data), val.Type().Bits())
if err != nil {
return err
}
val.SetFloat(i)
}
default:
return errors.New("unsupported type")
}
// </type>
if err = dec.Skip(); err != nil {
return err
}
}
return nil
}
func (dec *decoder) readTag() (string, []byte, error) {
var tok xml.Token
var err error
var name string
for {
if tok, err = dec.Token(); err != nil {
return "", nil, err
}
if t, ok := tok.(xml.StartElement); ok {
name = t.Name.Local
break
}
}
value, err := dec.readCharData()
if err != nil {
return "", nil, err
}
return name, value, dec.Skip()
}
func (dec *decoder) readCharData() ([]byte, error) {
var tok xml.Token
var err error
if tok, err = dec.Token(); err != nil {
return nil, err
}
if t, ok := tok.(xml.CharData); ok {
return []byte(t.Copy()), nil
} else {
return nil, invalidXmlError
}
}
func checkType(val reflect.Value, kinds ...reflect.Kind) error {
if len(kinds) == 0 {
return nil
}
if val.Kind() == reflect.Ptr {
val = val.Elem()
}
match := false
for _, kind := range kinds {
if val.Kind() == kind {
match = true
break
}
}
if !match {
return TypeMismatchError(fmt.Sprintf("error: type mismatch - can't unmarshal %v to %v",
val.Kind(), kinds[0]))
}
return nil
}