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-rw-r--r--src/encoding/xml/read.go775
1 files changed, 775 insertions, 0 deletions
diff --git a/src/encoding/xml/read.go b/src/encoding/xml/read.go
new file mode 100644
index 0000000..43be08e
--- /dev/null
+++ b/src/encoding/xml/read.go
@@ -0,0 +1,775 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xml
+
+import (
+ "bytes"
+ "encoding"
+ "errors"
+ "fmt"
+ "reflect"
+ "runtime"
+ "strconv"
+ "strings"
+)
+
+// BUG(rsc): Mapping between XML elements and data structures is inherently flawed:
+// an XML element is an order-dependent collection of anonymous
+// values, while a data structure is an order-independent collection
+// of named values.
+// See package json for a textual representation more suitable
+// to data structures.
+
+// Unmarshal parses the XML-encoded data and stores the result in
+// the value pointed to by v, which must be an arbitrary struct,
+// slice, or string. Well-formed data that does not fit into v is
+// discarded.
+//
+// Because Unmarshal uses the reflect package, it can only assign
+// to exported (upper case) fields. Unmarshal uses a case-sensitive
+// comparison to match XML element names to tag values and struct
+// field names.
+//
+// Unmarshal maps an XML element to a struct using the following rules.
+// In the rules, the tag of a field refers to the value associated with the
+// key 'xml' in the struct field's tag (see the example above).
+//
+// - If the struct has a field of type []byte or string with tag
+// ",innerxml", Unmarshal accumulates the raw XML nested inside the
+// element in that field. The rest of the rules still apply.
+//
+// - If the struct has a field named XMLName of type Name,
+// Unmarshal records the element name in that field.
+//
+// - If the XMLName field has an associated tag of the form
+// "name" or "namespace-URL name", the XML element must have
+// the given name (and, optionally, name space) or else Unmarshal
+// returns an error.
+//
+// - If the XML element has an attribute whose name matches a
+// struct field name with an associated tag containing ",attr" or
+// the explicit name in a struct field tag of the form "name,attr",
+// Unmarshal records the attribute value in that field.
+//
+// - If the XML element has an attribute not handled by the previous
+// rule and the struct has a field with an associated tag containing
+// ",any,attr", Unmarshal records the attribute value in the first
+// such field.
+//
+// - If the XML element contains character data, that data is
+// accumulated in the first struct field that has tag ",chardata".
+// The struct field may have type []byte or string.
+// If there is no such field, the character data is discarded.
+//
+// - If the XML element contains comments, they are accumulated in
+// the first struct field that has tag ",comment". The struct
+// field may have type []byte or string. If there is no such
+// field, the comments are discarded.
+//
+// - If the XML element contains a sub-element whose name matches
+// the prefix of a tag formatted as "a" or "a>b>c", unmarshal
+// will descend into the XML structure looking for elements with the
+// given names, and will map the innermost elements to that struct
+// field. A tag starting with ">" is equivalent to one starting
+// with the field name followed by ">".
+//
+// - If the XML element contains a sub-element whose name matches
+// a struct field's XMLName tag and the struct field has no
+// explicit name tag as per the previous rule, unmarshal maps
+// the sub-element to that struct field.
+//
+// - If the XML element contains a sub-element whose name matches a
+// field without any mode flags (",attr", ",chardata", etc), Unmarshal
+// maps the sub-element to that struct field.
+//
+// - If the XML element contains a sub-element that hasn't matched any
+// of the above rules and the struct has a field with tag ",any",
+// unmarshal maps the sub-element to that struct field.
+//
+// - An anonymous struct field is handled as if the fields of its
+// value were part of the outer struct.
+//
+// - A struct field with tag "-" is never unmarshaled into.
+//
+// If Unmarshal encounters a field type that implements the Unmarshaler
+// interface, Unmarshal calls its UnmarshalXML method to produce the value from
+// the XML element. Otherwise, if the value implements
+// encoding.TextUnmarshaler, Unmarshal calls that value's UnmarshalText method.
+//
+// Unmarshal maps an XML element to a string or []byte by saving the
+// concatenation of that element's character data in the string or
+// []byte. The saved []byte is never nil.
+//
+// Unmarshal maps an attribute value to a string or []byte by saving
+// the value in the string or slice.
+//
+// Unmarshal maps an attribute value to an Attr by saving the attribute,
+// including its name, in the Attr.
+//
+// Unmarshal maps an XML element or attribute value to a slice by
+// extending the length of the slice and mapping the element or attribute
+// to the newly created value.
+//
+// Unmarshal maps an XML element or attribute value to a bool by
+// setting it to the boolean value represented by the string. Whitespace
+// is trimmed and ignored.
+//
+// Unmarshal maps an XML element or attribute value to an integer or
+// floating-point field by setting the field to the result of
+// interpreting the string value in decimal. There is no check for
+// overflow. Whitespace is trimmed and ignored.
+//
+// Unmarshal maps an XML element to a Name by recording the element
+// name.
+//
+// Unmarshal maps an XML element to a pointer by setting the pointer
+// to a freshly allocated value and then mapping the element to that value.
+//
+// A missing element or empty attribute value will be unmarshaled as a zero value.
+// If the field is a slice, a zero value will be appended to the field. Otherwise, the
+// field will be set to its zero value.
+func Unmarshal(data []byte, v any) error {
+ return NewDecoder(bytes.NewReader(data)).Decode(v)
+}
+
+// Decode works like Unmarshal, except it reads the decoder
+// stream to find the start element.
+func (d *Decoder) Decode(v any) error {
+ return d.DecodeElement(v, nil)
+}
+
+// DecodeElement works like Unmarshal except that it takes
+// a pointer to the start XML element to decode into v.
+// It is useful when a client reads some raw XML tokens itself
+// but also wants to defer to Unmarshal for some elements.
+func (d *Decoder) DecodeElement(v any, start *StartElement) error {
+ val := reflect.ValueOf(v)
+ if val.Kind() != reflect.Pointer {
+ return errors.New("non-pointer passed to Unmarshal")
+ }
+
+ if val.IsNil() {
+ return errors.New("nil pointer passed to Unmarshal")
+ }
+ return d.unmarshal(val.Elem(), start, 0)
+}
+
+// An UnmarshalError represents an error in the unmarshaling process.
+type UnmarshalError string
+
+func (e UnmarshalError) Error() string { return string(e) }
+
+// Unmarshaler is the interface implemented by objects that can unmarshal
+// an XML element description of themselves.
+//
+// UnmarshalXML decodes a single XML element
+// beginning with the given start element.
+// If it returns an error, the outer call to Unmarshal stops and
+// returns that error.
+// UnmarshalXML must consume exactly one XML element.
+// One common implementation strategy is to unmarshal into
+// a separate value with a layout matching the expected XML
+// using d.DecodeElement, and then to copy the data from
+// that value into the receiver.
+// Another common strategy is to use d.Token to process the
+// XML object one token at a time.
+// UnmarshalXML may not use d.RawToken.
+type Unmarshaler interface {
+ UnmarshalXML(d *Decoder, start StartElement) error
+}
+
+// UnmarshalerAttr is the interface implemented by objects that can unmarshal
+// an XML attribute description of themselves.
+//
+// UnmarshalXMLAttr decodes a single XML attribute.
+// If it returns an error, the outer call to Unmarshal stops and
+// returns that error.
+// UnmarshalXMLAttr is used only for struct fields with the
+// "attr" option in the field tag.
+type UnmarshalerAttr interface {
+ UnmarshalXMLAttr(attr Attr) error
+}
+
+// receiverType returns the receiver type to use in an expression like "%s.MethodName".
+func receiverType(val any) string {
+ t := reflect.TypeOf(val)
+ if t.Name() != "" {
+ return t.String()
+ }
+ return "(" + t.String() + ")"
+}
+
+// unmarshalInterface unmarshals a single XML element into val.
+// start is the opening tag of the element.
+func (d *Decoder) unmarshalInterface(val Unmarshaler, start *StartElement) error {
+ // Record that decoder must stop at end tag corresponding to start.
+ d.pushEOF()
+
+ d.unmarshalDepth++
+ err := val.UnmarshalXML(d, *start)
+ d.unmarshalDepth--
+ if err != nil {
+ d.popEOF()
+ return err
+ }
+
+ if !d.popEOF() {
+ return fmt.Errorf("xml: %s.UnmarshalXML did not consume entire <%s> element", receiverType(val), start.Name.Local)
+ }
+
+ return nil
+}
+
+// unmarshalTextInterface unmarshals a single XML element into val.
+// The chardata contained in the element (but not its children)
+// is passed to the text unmarshaler.
+func (d *Decoder) unmarshalTextInterface(val encoding.TextUnmarshaler) error {
+ var buf []byte
+ depth := 1
+ for depth > 0 {
+ t, err := d.Token()
+ if err != nil {
+ return err
+ }
+ switch t := t.(type) {
+ case CharData:
+ if depth == 1 {
+ buf = append(buf, t...)
+ }
+ case StartElement:
+ depth++
+ case EndElement:
+ depth--
+ }
+ }
+ return val.UnmarshalText(buf)
+}
+
+// unmarshalAttr unmarshals a single XML attribute into val.
+func (d *Decoder) unmarshalAttr(val reflect.Value, attr Attr) error {
+ if val.Kind() == reflect.Pointer {
+ if val.IsNil() {
+ val.Set(reflect.New(val.Type().Elem()))
+ }
+ val = val.Elem()
+ }
+ if val.CanInterface() && val.Type().Implements(unmarshalerAttrType) {
+ // This is an unmarshaler with a non-pointer receiver,
+ // so it's likely to be incorrect, but we do what we're told.
+ return val.Interface().(UnmarshalerAttr).UnmarshalXMLAttr(attr)
+ }
+ if val.CanAddr() {
+ pv := val.Addr()
+ if pv.CanInterface() && pv.Type().Implements(unmarshalerAttrType) {
+ return pv.Interface().(UnmarshalerAttr).UnmarshalXMLAttr(attr)
+ }
+ }
+
+ // Not an UnmarshalerAttr; try encoding.TextUnmarshaler.
+ if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
+ // This is an unmarshaler with a non-pointer receiver,
+ // so it's likely to be incorrect, but we do what we're told.
+ return val.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(attr.Value))
+ }
+ if val.CanAddr() {
+ pv := val.Addr()
+ if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+ return pv.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(attr.Value))
+ }
+ }
+
+ if val.Type().Kind() == reflect.Slice && val.Type().Elem().Kind() != reflect.Uint8 {
+ // Slice of element values.
+ // Grow slice.
+ n := val.Len()
+ val.Set(reflect.Append(val, reflect.Zero(val.Type().Elem())))
+
+ // Recur to read element into slice.
+ if err := d.unmarshalAttr(val.Index(n), attr); err != nil {
+ val.SetLen(n)
+ return err
+ }
+ return nil
+ }
+
+ if val.Type() == attrType {
+ val.Set(reflect.ValueOf(attr))
+ return nil
+ }
+
+ return copyValue(val, []byte(attr.Value))
+}
+
+var (
+ attrType = reflect.TypeOf(Attr{})
+ unmarshalerType = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+ unmarshalerAttrType = reflect.TypeOf((*UnmarshalerAttr)(nil)).Elem()
+ textUnmarshalerType = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+)
+
+const (
+ maxUnmarshalDepth = 10000
+ maxUnmarshalDepthWasm = 5000 // go.dev/issue/56498
+)
+
+var errUnmarshalDepth = errors.New("exceeded max depth")
+
+// Unmarshal a single XML element into val.
+func (d *Decoder) unmarshal(val reflect.Value, start *StartElement, depth int) error {
+ if depth >= maxUnmarshalDepth || runtime.GOARCH == "wasm" && depth >= maxUnmarshalDepthWasm {
+ return errUnmarshalDepth
+ }
+ // Find start element if we need it.
+ if start == nil {
+ for {
+ tok, err := d.Token()
+ if err != nil {
+ return err
+ }
+ if t, ok := tok.(StartElement); ok {
+ start = &t
+ break
+ }
+ }
+ }
+
+ // Load value from interface, but only if the result will be
+ // usefully addressable.
+ if val.Kind() == reflect.Interface && !val.IsNil() {
+ e := val.Elem()
+ if e.Kind() == reflect.Pointer && !e.IsNil() {
+ val = e
+ }
+ }
+
+ if val.Kind() == reflect.Pointer {
+ if val.IsNil() {
+ val.Set(reflect.New(val.Type().Elem()))
+ }
+ val = val.Elem()
+ }
+
+ if val.CanInterface() && val.Type().Implements(unmarshalerType) {
+ // This is an unmarshaler with a non-pointer receiver,
+ // so it's likely to be incorrect, but we do what we're told.
+ return d.unmarshalInterface(val.Interface().(Unmarshaler), start)
+ }
+
+ if val.CanAddr() {
+ pv := val.Addr()
+ if pv.CanInterface() && pv.Type().Implements(unmarshalerType) {
+ return d.unmarshalInterface(pv.Interface().(Unmarshaler), start)
+ }
+ }
+
+ if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
+ return d.unmarshalTextInterface(val.Interface().(encoding.TextUnmarshaler))
+ }
+
+ if val.CanAddr() {
+ pv := val.Addr()
+ if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+ return d.unmarshalTextInterface(pv.Interface().(encoding.TextUnmarshaler))
+ }
+ }
+
+ var (
+ data []byte
+ saveData reflect.Value
+ comment []byte
+ saveComment reflect.Value
+ saveXML reflect.Value
+ saveXMLIndex int
+ saveXMLData []byte
+ saveAny reflect.Value
+ sv reflect.Value
+ tinfo *typeInfo
+ err error
+ )
+
+ switch v := val; v.Kind() {
+ default:
+ return errors.New("unknown type " + v.Type().String())
+
+ case reflect.Interface:
+ // TODO: For now, simply ignore the field. In the near
+ // future we may choose to unmarshal the start
+ // element on it, if not nil.
+ return d.Skip()
+
+ case reflect.Slice:
+ typ := v.Type()
+ if typ.Elem().Kind() == reflect.Uint8 {
+ // []byte
+ saveData = v
+ break
+ }
+
+ // Slice of element values.
+ // Grow slice.
+ n := v.Len()
+ v.Set(reflect.Append(val, reflect.Zero(v.Type().Elem())))
+
+ // Recur to read element into slice.
+ if err := d.unmarshal(v.Index(n), start, depth+1); err != nil {
+ v.SetLen(n)
+ return err
+ }
+ return nil
+
+ case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr, reflect.String:
+ saveData = v
+
+ case reflect.Struct:
+ typ := v.Type()
+ if typ == nameType {
+ v.Set(reflect.ValueOf(start.Name))
+ break
+ }
+
+ sv = v
+ tinfo, err = getTypeInfo(typ)
+ if err != nil {
+ return err
+ }
+
+ // Validate and assign element name.
+ if tinfo.xmlname != nil {
+ finfo := tinfo.xmlname
+ if finfo.name != "" && finfo.name != start.Name.Local {
+ return UnmarshalError("expected element type <" + finfo.name + "> but have <" + start.Name.Local + ">")
+ }
+ if finfo.xmlns != "" && finfo.xmlns != start.Name.Space {
+ e := "expected element <" + finfo.name + "> in name space " + finfo.xmlns + " but have "
+ if start.Name.Space == "" {
+ e += "no name space"
+ } else {
+ e += start.Name.Space
+ }
+ return UnmarshalError(e)
+ }
+ fv := finfo.value(sv, initNilPointers)
+ if _, ok := fv.Interface().(Name); ok {
+ fv.Set(reflect.ValueOf(start.Name))
+ }
+ }
+
+ // Assign attributes.
+ for _, a := range start.Attr {
+ handled := false
+ any := -1
+ for i := range tinfo.fields {
+ finfo := &tinfo.fields[i]
+ switch finfo.flags & fMode {
+ case fAttr:
+ strv := finfo.value(sv, initNilPointers)
+ if a.Name.Local == finfo.name && (finfo.xmlns == "" || finfo.xmlns == a.Name.Space) {
+ if err := d.unmarshalAttr(strv, a); err != nil {
+ return err
+ }
+ handled = true
+ }
+
+ case fAny | fAttr:
+ if any == -1 {
+ any = i
+ }
+ }
+ }
+ if !handled && any >= 0 {
+ finfo := &tinfo.fields[any]
+ strv := finfo.value(sv, initNilPointers)
+ if err := d.unmarshalAttr(strv, a); err != nil {
+ return err
+ }
+ }
+ }
+
+ // Determine whether we need to save character data or comments.
+ for i := range tinfo.fields {
+ finfo := &tinfo.fields[i]
+ switch finfo.flags & fMode {
+ case fCDATA, fCharData:
+ if !saveData.IsValid() {
+ saveData = finfo.value(sv, initNilPointers)
+ }
+
+ case fComment:
+ if !saveComment.IsValid() {
+ saveComment = finfo.value(sv, initNilPointers)
+ }
+
+ case fAny, fAny | fElement:
+ if !saveAny.IsValid() {
+ saveAny = finfo.value(sv, initNilPointers)
+ }
+
+ case fInnerXML:
+ if !saveXML.IsValid() {
+ saveXML = finfo.value(sv, initNilPointers)
+ if d.saved == nil {
+ saveXMLIndex = 0
+ d.saved = new(bytes.Buffer)
+ } else {
+ saveXMLIndex = d.savedOffset()
+ }
+ }
+ }
+ }
+ }
+
+ // Find end element.
+ // Process sub-elements along the way.
+Loop:
+ for {
+ var savedOffset int
+ if saveXML.IsValid() {
+ savedOffset = d.savedOffset()
+ }
+ tok, err := d.Token()
+ if err != nil {
+ return err
+ }
+ switch t := tok.(type) {
+ case StartElement:
+ consumed := false
+ if sv.IsValid() {
+ // unmarshalPath can call unmarshal, so we need to pass the depth through so that
+ // we can continue to enforce the maximum recursion limit.
+ consumed, err = d.unmarshalPath(tinfo, sv, nil, &t, depth)
+ if err != nil {
+ return err
+ }
+ if !consumed && saveAny.IsValid() {
+ consumed = true
+ if err := d.unmarshal(saveAny, &t, depth+1); err != nil {
+ return err
+ }
+ }
+ }
+ if !consumed {
+ if err := d.Skip(); err != nil {
+ return err
+ }
+ }
+
+ case EndElement:
+ if saveXML.IsValid() {
+ saveXMLData = d.saved.Bytes()[saveXMLIndex:savedOffset]
+ if saveXMLIndex == 0 {
+ d.saved = nil
+ }
+ }
+ break Loop
+
+ case CharData:
+ if saveData.IsValid() {
+ data = append(data, t...)
+ }
+
+ case Comment:
+ if saveComment.IsValid() {
+ comment = append(comment, t...)
+ }
+ }
+ }
+
+ if saveData.IsValid() && saveData.CanInterface() && saveData.Type().Implements(textUnmarshalerType) {
+ if err := saveData.Interface().(encoding.TextUnmarshaler).UnmarshalText(data); err != nil {
+ return err
+ }
+ saveData = reflect.Value{}
+ }
+
+ if saveData.IsValid() && saveData.CanAddr() {
+ pv := saveData.Addr()
+ if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+ if err := pv.Interface().(encoding.TextUnmarshaler).UnmarshalText(data); err != nil {
+ return err
+ }
+ saveData = reflect.Value{}
+ }
+ }
+
+ if err := copyValue(saveData, data); err != nil {
+ return err
+ }
+
+ switch t := saveComment; t.Kind() {
+ case reflect.String:
+ t.SetString(string(comment))
+ case reflect.Slice:
+ t.Set(reflect.ValueOf(comment))
+ }
+
+ switch t := saveXML; t.Kind() {
+ case reflect.String:
+ t.SetString(string(saveXMLData))
+ case reflect.Slice:
+ if t.Type().Elem().Kind() == reflect.Uint8 {
+ t.Set(reflect.ValueOf(saveXMLData))
+ }
+ }
+
+ return nil
+}
+
+func copyValue(dst reflect.Value, src []byte) (err error) {
+ dst0 := dst
+
+ if dst.Kind() == reflect.Pointer {
+ if dst.IsNil() {
+ dst.Set(reflect.New(dst.Type().Elem()))
+ }
+ dst = dst.Elem()
+ }
+
+ // Save accumulated data.
+ switch dst.Kind() {
+ case reflect.Invalid:
+ // Probably a comment.
+ default:
+ return errors.New("cannot unmarshal into " + dst0.Type().String())
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ if len(src) == 0 {
+ dst.SetInt(0)
+ return nil
+ }
+ itmp, err := strconv.ParseInt(strings.TrimSpace(string(src)), 10, dst.Type().Bits())
+ if err != nil {
+ return err
+ }
+ dst.SetInt(itmp)
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ if len(src) == 0 {
+ dst.SetUint(0)
+ return nil
+ }
+ utmp, err := strconv.ParseUint(strings.TrimSpace(string(src)), 10, dst.Type().Bits())
+ if err != nil {
+ return err
+ }
+ dst.SetUint(utmp)
+ case reflect.Float32, reflect.Float64:
+ if len(src) == 0 {
+ dst.SetFloat(0)
+ return nil
+ }
+ ftmp, err := strconv.ParseFloat(strings.TrimSpace(string(src)), dst.Type().Bits())
+ if err != nil {
+ return err
+ }
+ dst.SetFloat(ftmp)
+ case reflect.Bool:
+ if len(src) == 0 {
+ dst.SetBool(false)
+ return nil
+ }
+ value, err := strconv.ParseBool(strings.TrimSpace(string(src)))
+ if err != nil {
+ return err
+ }
+ dst.SetBool(value)
+ case reflect.String:
+ dst.SetString(string(src))
+ case reflect.Slice:
+ if len(src) == 0 {
+ // non-nil to flag presence
+ src = []byte{}
+ }
+ dst.SetBytes(src)
+ }
+ return nil
+}
+
+// unmarshalPath walks down an XML structure looking for wanted
+// paths, and calls unmarshal on them.
+// The consumed result tells whether XML elements have been consumed
+// from the Decoder until start's matching end element, or if it's
+// still untouched because start is uninteresting for sv's fields.
+func (d *Decoder) unmarshalPath(tinfo *typeInfo, sv reflect.Value, parents []string, start *StartElement, depth int) (consumed bool, err error) {
+ recurse := false
+Loop:
+ for i := range tinfo.fields {
+ finfo := &tinfo.fields[i]
+ if finfo.flags&fElement == 0 || len(finfo.parents) < len(parents) || finfo.xmlns != "" && finfo.xmlns != start.Name.Space {
+ continue
+ }
+ for j := range parents {
+ if parents[j] != finfo.parents[j] {
+ continue Loop
+ }
+ }
+ if len(finfo.parents) == len(parents) && finfo.name == start.Name.Local {
+ // It's a perfect match, unmarshal the field.
+ return true, d.unmarshal(finfo.value(sv, initNilPointers), start, depth+1)
+ }
+ if len(finfo.parents) > len(parents) && finfo.parents[len(parents)] == start.Name.Local {
+ // It's a prefix for the field. Break and recurse
+ // since it's not ok for one field path to be itself
+ // the prefix for another field path.
+ recurse = true
+
+ // We can reuse the same slice as long as we
+ // don't try to append to it.
+ parents = finfo.parents[:len(parents)+1]
+ break
+ }
+ }
+ if !recurse {
+ // We have no business with this element.
+ return false, nil
+ }
+ // The element is not a perfect match for any field, but one
+ // or more fields have the path to this element as a parent
+ // prefix. Recurse and attempt to match these.
+ for {
+ var tok Token
+ tok, err = d.Token()
+ if err != nil {
+ return true, err
+ }
+ switch t := tok.(type) {
+ case StartElement:
+ // the recursion depth of unmarshalPath is limited to the path length specified
+ // by the struct field tag, so we don't increment the depth here.
+ consumed2, err := d.unmarshalPath(tinfo, sv, parents, &t, depth)
+ if err != nil {
+ return true, err
+ }
+ if !consumed2 {
+ if err := d.Skip(); err != nil {
+ return true, err
+ }
+ }
+ case EndElement:
+ return true, nil
+ }
+ }
+}
+
+// Skip reads tokens until it has consumed the end element
+// matching the most recent start element already consumed,
+// skipping nested structures.
+// It returns nil if it finds an end element matching the start
+// element; otherwise it returns an error describing the problem.
+func (d *Decoder) Skip() error {
+ var depth int64
+ for {
+ tok, err := d.Token()
+ if err != nil {
+ return err
+ }
+ switch tok.(type) {
+ case StartElement:
+ depth++
+ case EndElement:
+ if depth == 0 {
+ return nil
+ }
+ depth--
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-13 01:19:27 +0000