summaryrefslogtreecommitdiff
path: root/src/encoding/xml/marshal.go
diff options
context:
space:
mode:
Diffstat (limited to 'src/encoding/xml/marshal.go')
-rw-r--r--src/encoding/xml/marshal.go938
1 files changed, 938 insertions, 0 deletions
diff --git a/src/encoding/xml/marshal.go b/src/encoding/xml/marshal.go
new file mode 100644
index 000000000..8c6342013
--- /dev/null
+++ b/src/encoding/xml/marshal.go
@@ -0,0 +1,938 @@
+// Copyright 2011 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 (
+ "bufio"
+ "bytes"
+ "encoding"
+ "fmt"
+ "io"
+ "reflect"
+ "strconv"
+ "strings"
+)
+
+const (
+ // A generic XML header suitable for use with the output of Marshal.
+ // This is not automatically added to any output of this package,
+ // it is provided as a convenience.
+ Header = `<?xml version="1.0" encoding="UTF-8"?>` + "\n"
+)
+
+// Marshal returns the XML encoding of v.
+//
+// Marshal handles an array or slice by marshalling each of the elements.
+// Marshal handles a pointer by marshalling the value it points at or, if the
+// pointer is nil, by writing nothing. Marshal handles an interface value by
+// marshalling the value it contains or, if the interface value is nil, by
+// writing nothing. Marshal handles all other data by writing one or more XML
+// elements containing the data.
+//
+// The name for the XML elements is taken from, in order of preference:
+// - the tag on the XMLName field, if the data is a struct
+// - the value of the XMLName field of type xml.Name
+// - the tag of the struct field used to obtain the data
+// - the name of the struct field used to obtain the data
+// - the name of the marshalled type
+//
+// The XML element for a struct contains marshalled elements for each of the
+// exported fields of the struct, with these exceptions:
+// - the XMLName field, described above, is omitted.
+// - a field with tag "-" is omitted.
+// - a field with tag "name,attr" becomes an attribute with
+// the given name in the XML element.
+// - a field with tag ",attr" becomes an attribute with the
+// field name in the XML element.
+// - a field with tag ",chardata" is written as character data,
+// not as an XML element.
+// - a field with tag ",innerxml" is written verbatim, not subject
+// to the usual marshalling procedure.
+// - a field with tag ",comment" is written as an XML comment, not
+// subject to the usual marshalling procedure. It must not contain
+// the "--" string within it.
+// - a field with a tag including the "omitempty" option is omitted
+// if the field value is empty. The empty values are false, 0, any
+// nil pointer or interface value, and any array, slice, map, or
+// string of length zero.
+// - an anonymous struct field is handled as if the fields of its
+// value were part of the outer struct.
+//
+// If a field uses a tag "a>b>c", then the element c will be nested inside
+// parent elements a and b. Fields that appear next to each other that name
+// the same parent will be enclosed in one XML element.
+//
+// See MarshalIndent for an example.
+//
+// Marshal will return an error if asked to marshal a channel, function, or map.
+func Marshal(v interface{}) ([]byte, error) {
+ var b bytes.Buffer
+ if err := NewEncoder(&b).Encode(v); err != nil {
+ return nil, err
+ }
+ return b.Bytes(), nil
+}
+
+// Marshaler is the interface implemented by objects that can marshal
+// themselves into valid XML elements.
+//
+// MarshalXML encodes the receiver as zero or more XML elements.
+// By convention, arrays or slices are typically encoded as a sequence
+// of elements, one per entry.
+// Using start as the element tag is not required, but doing so
+// will enable Unmarshal to match the XML elements to the correct
+// struct field.
+// One common implementation strategy is to construct a separate
+// value with a layout corresponding to the desired XML and then
+// to encode it using e.EncodeElement.
+// Another common strategy is to use repeated calls to e.EncodeToken
+// to generate the XML output one token at a time.
+// The sequence of encoded tokens must make up zero or more valid
+// XML elements.
+type Marshaler interface {
+ MarshalXML(e *Encoder, start StartElement) error
+}
+
+// MarshalerAttr is the interface implemented by objects that can marshal
+// themselves into valid XML attributes.
+//
+// MarshalXMLAttr returns an XML attribute with the encoded value of the receiver.
+// Using name as the attribute name is not required, but doing so
+// will enable Unmarshal to match the attribute to the correct
+// struct field.
+// If MarshalXMLAttr returns the zero attribute Attr{}, no attribute
+// will be generated in the output.
+// MarshalXMLAttr is used only for struct fields with the
+// "attr" option in the field tag.
+type MarshalerAttr interface {
+ MarshalXMLAttr(name Name) (Attr, error)
+}
+
+// MarshalIndent works like Marshal, but each XML element begins on a new
+// indented line that starts with prefix and is followed by one or more
+// copies of indent according to the nesting depth.
+func MarshalIndent(v interface{}, prefix, indent string) ([]byte, error) {
+ var b bytes.Buffer
+ enc := NewEncoder(&b)
+ enc.Indent(prefix, indent)
+ if err := enc.Encode(v); err != nil {
+ return nil, err
+ }
+ return b.Bytes(), nil
+}
+
+// An Encoder writes XML data to an output stream.
+type Encoder struct {
+ p printer
+}
+
+// NewEncoder returns a new encoder that writes to w.
+func NewEncoder(w io.Writer) *Encoder {
+ e := &Encoder{printer{Writer: bufio.NewWriter(w)}}
+ e.p.encoder = e
+ return e
+}
+
+// Indent sets the encoder to generate XML in which each element
+// begins on a new indented line that starts with prefix and is followed by
+// one or more copies of indent according to the nesting depth.
+func (enc *Encoder) Indent(prefix, indent string) {
+ enc.p.prefix = prefix
+ enc.p.indent = indent
+}
+
+// Encode writes the XML encoding of v to the stream.
+//
+// See the documentation for Marshal for details about the conversion
+// of Go values to XML.
+//
+// Encode calls Flush before returning.
+func (enc *Encoder) Encode(v interface{}) error {
+ err := enc.p.marshalValue(reflect.ValueOf(v), nil, nil)
+ if err != nil {
+ return err
+ }
+ return enc.p.Flush()
+}
+
+// EncodeElement writes the XML encoding of v to the stream,
+// using start as the outermost tag in the encoding.
+//
+// See the documentation for Marshal for details about the conversion
+// of Go values to XML.
+//
+// EncodeElement calls Flush before returning.
+func (enc *Encoder) EncodeElement(v interface{}, start StartElement) error {
+ err := enc.p.marshalValue(reflect.ValueOf(v), nil, &start)
+ if err != nil {
+ return err
+ }
+ return enc.p.Flush()
+}
+
+var (
+ endComment = []byte("-->")
+ endProcInst = []byte("?>")
+ endDirective = []byte(">")
+)
+
+// EncodeToken writes the given XML token to the stream.
+// It returns an error if StartElement and EndElement tokens are not properly matched.
+//
+// EncodeToken does not call Flush, because usually it is part of a larger operation
+// such as Encode or EncodeElement (or a custom Marshaler's MarshalXML invoked
+// during those), and those will call Flush when finished.
+// Callers that create an Encoder and then invoke EncodeToken directly, without
+// using Encode or EncodeElement, need to call Flush when finished to ensure
+// that the XML is written to the underlying writer.
+//
+// EncodeToken allows writing a ProcInst with Target set to "xml" only as the first token
+// in the stream.
+func (enc *Encoder) EncodeToken(t Token) error {
+ p := &enc.p
+ switch t := t.(type) {
+ case StartElement:
+ if err := p.writeStart(&t); err != nil {
+ return err
+ }
+ case EndElement:
+ if err := p.writeEnd(t.Name); err != nil {
+ return err
+ }
+ case CharData:
+ EscapeText(p, t)
+ case Comment:
+ if bytes.Contains(t, endComment) {
+ return fmt.Errorf("xml: EncodeToken of Comment containing --> marker")
+ }
+ p.WriteString("<!--")
+ p.Write(t)
+ p.WriteString("-->")
+ return p.cachedWriteError()
+ case ProcInst:
+ // First token to be encoded which is also a ProcInst with target of xml
+ // is the xml declaration. The only ProcInst where target of xml is allowed.
+ if t.Target == "xml" && p.Buffered() != 0 {
+ return fmt.Errorf("xml: EncodeToken of ProcInst xml target only valid for xml declaration, first token encoded")
+ }
+ if !isNameString(t.Target) {
+ return fmt.Errorf("xml: EncodeToken of ProcInst with invalid Target")
+ }
+ if bytes.Contains(t.Inst, endProcInst) {
+ return fmt.Errorf("xml: EncodeToken of ProcInst containing ?> marker")
+ }
+ p.WriteString("<?")
+ p.WriteString(t.Target)
+ if len(t.Inst) > 0 {
+ p.WriteByte(' ')
+ p.Write(t.Inst)
+ }
+ p.WriteString("?>")
+ case Directive:
+ if bytes.Contains(t, endDirective) {
+ return fmt.Errorf("xml: EncodeToken of Directive containing > marker")
+ }
+ p.WriteString("<!")
+ p.Write(t)
+ p.WriteString(">")
+ }
+ return p.cachedWriteError()
+}
+
+// Flush flushes any buffered XML to the underlying writer.
+// See the EncodeToken documentation for details about when it is necessary.
+func (enc *Encoder) Flush() error {
+ return enc.p.Flush()
+}
+
+type printer struct {
+ *bufio.Writer
+ encoder *Encoder
+ seq int
+ indent string
+ prefix string
+ depth int
+ indentedIn bool
+ putNewline bool
+ attrNS map[string]string // map prefix -> name space
+ attrPrefix map[string]string // map name space -> prefix
+ prefixes []string
+ tags []Name
+}
+
+// createAttrPrefix finds the name space prefix attribute to use for the given name space,
+// defining a new prefix if necessary. It returns the prefix.
+func (p *printer) createAttrPrefix(url string) string {
+ if prefix := p.attrPrefix[url]; prefix != "" {
+ return prefix
+ }
+
+ // The "http://www.w3.org/XML/1998/namespace" name space is predefined as "xml"
+ // and must be referred to that way.
+ // (The "http://www.w3.org/2000/xmlns/" name space is also predefined as "xmlns",
+ // but users should not be trying to use that one directly - that's our job.)
+ if url == xmlURL {
+ return "xml"
+ }
+
+ // Need to define a new name space.
+ if p.attrPrefix == nil {
+ p.attrPrefix = make(map[string]string)
+ p.attrNS = make(map[string]string)
+ }
+
+ // Pick a name. We try to use the final element of the path
+ // but fall back to _.
+ prefix := strings.TrimRight(url, "/")
+ if i := strings.LastIndex(prefix, "/"); i >= 0 {
+ prefix = prefix[i+1:]
+ }
+ if prefix == "" || !isName([]byte(prefix)) || strings.Contains(prefix, ":") {
+ prefix = "_"
+ }
+ if strings.HasPrefix(prefix, "xml") {
+ // xmlanything is reserved.
+ prefix = "_" + prefix
+ }
+ if p.attrNS[prefix] != "" {
+ // Name is taken. Find a better one.
+ for p.seq++; ; p.seq++ {
+ if id := prefix + "_" + strconv.Itoa(p.seq); p.attrNS[id] == "" {
+ prefix = id
+ break
+ }
+ }
+ }
+
+ p.attrPrefix[url] = prefix
+ p.attrNS[prefix] = url
+
+ p.WriteString(`xmlns:`)
+ p.WriteString(prefix)
+ p.WriteString(`="`)
+ EscapeText(p, []byte(url))
+ p.WriteString(`" `)
+
+ p.prefixes = append(p.prefixes, prefix)
+
+ return prefix
+}
+
+// deleteAttrPrefix removes an attribute name space prefix.
+func (p *printer) deleteAttrPrefix(prefix string) {
+ delete(p.attrPrefix, p.attrNS[prefix])
+ delete(p.attrNS, prefix)
+}
+
+func (p *printer) markPrefix() {
+ p.prefixes = append(p.prefixes, "")
+}
+
+func (p *printer) popPrefix() {
+ for len(p.prefixes) > 0 {
+ prefix := p.prefixes[len(p.prefixes)-1]
+ p.prefixes = p.prefixes[:len(p.prefixes)-1]
+ if prefix == "" {
+ break
+ }
+ p.deleteAttrPrefix(prefix)
+ }
+}
+
+var (
+ marshalerType = reflect.TypeOf((*Marshaler)(nil)).Elem()
+ marshalerAttrType = reflect.TypeOf((*MarshalerAttr)(nil)).Elem()
+ textMarshalerType = reflect.TypeOf((*encoding.TextMarshaler)(nil)).Elem()
+)
+
+// marshalValue writes one or more XML elements representing val.
+// If val was obtained from a struct field, finfo must have its details.
+func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo, startTemplate *StartElement) error {
+ if startTemplate != nil && startTemplate.Name.Local == "" {
+ return fmt.Errorf("xml: EncodeElement of StartElement with missing name")
+ }
+
+ if !val.IsValid() {
+ return nil
+ }
+ if finfo != nil && finfo.flags&fOmitEmpty != 0 && isEmptyValue(val) {
+ return nil
+ }
+
+ // Drill into interfaces and pointers.
+ // This can turn into an infinite loop given a cyclic chain,
+ // but it matches the Go 1 behavior.
+ for val.Kind() == reflect.Interface || val.Kind() == reflect.Ptr {
+ if val.IsNil() {
+ return nil
+ }
+ val = val.Elem()
+ }
+
+ kind := val.Kind()
+ typ := val.Type()
+
+ // Check for marshaler.
+ if val.CanInterface() && typ.Implements(marshalerType) {
+ return p.marshalInterface(val.Interface().(Marshaler), defaultStart(typ, finfo, startTemplate))
+ }
+ if val.CanAddr() {
+ pv := val.Addr()
+ if pv.CanInterface() && pv.Type().Implements(marshalerType) {
+ return p.marshalInterface(pv.Interface().(Marshaler), defaultStart(pv.Type(), finfo, startTemplate))
+ }
+ }
+
+ // Check for text marshaler.
+ if val.CanInterface() && typ.Implements(textMarshalerType) {
+ return p.marshalTextInterface(val.Interface().(encoding.TextMarshaler), defaultStart(typ, finfo, startTemplate))
+ }
+ if val.CanAddr() {
+ pv := val.Addr()
+ if pv.CanInterface() && pv.Type().Implements(textMarshalerType) {
+ return p.marshalTextInterface(pv.Interface().(encoding.TextMarshaler), defaultStart(pv.Type(), finfo, startTemplate))
+ }
+ }
+
+ // Slices and arrays iterate over the elements. They do not have an enclosing tag.
+ if (kind == reflect.Slice || kind == reflect.Array) && typ.Elem().Kind() != reflect.Uint8 {
+ for i, n := 0, val.Len(); i < n; i++ {
+ if err := p.marshalValue(val.Index(i), finfo, startTemplate); err != nil {
+ return err
+ }
+ }
+ return nil
+ }
+
+ tinfo, err := getTypeInfo(typ)
+ if err != nil {
+ return err
+ }
+
+ // Create start element.
+ // Precedence for the XML element name is:
+ // 0. startTemplate
+ // 1. XMLName field in underlying struct;
+ // 2. field name/tag in the struct field; and
+ // 3. type name
+ var start StartElement
+
+ if startTemplate != nil {
+ start.Name = startTemplate.Name
+ start.Attr = append(start.Attr, startTemplate.Attr...)
+ } else if tinfo.xmlname != nil {
+ xmlname := tinfo.xmlname
+ if xmlname.name != "" {
+ start.Name.Space, start.Name.Local = xmlname.xmlns, xmlname.name
+ } else if v, ok := xmlname.value(val).Interface().(Name); ok && v.Local != "" {
+ start.Name = v
+ }
+ }
+ if start.Name.Local == "" && finfo != nil {
+ start.Name.Space, start.Name.Local = finfo.xmlns, finfo.name
+ }
+ if start.Name.Local == "" {
+ name := typ.Name()
+ if name == "" {
+ return &UnsupportedTypeError{typ}
+ }
+ start.Name.Local = name
+ }
+
+ // Attributes
+ for i := range tinfo.fields {
+ finfo := &tinfo.fields[i]
+ if finfo.flags&fAttr == 0 {
+ continue
+ }
+ fv := finfo.value(val)
+ name := Name{Space: finfo.xmlns, Local: finfo.name}
+
+ if finfo.flags&fOmitEmpty != 0 && isEmptyValue(fv) {
+ continue
+ }
+
+ if fv.Kind() == reflect.Interface && fv.IsNil() {
+ continue
+ }
+
+ if fv.CanInterface() && fv.Type().Implements(marshalerAttrType) {
+ attr, err := fv.Interface().(MarshalerAttr).MarshalXMLAttr(name)
+ if err != nil {
+ return err
+ }
+ if attr.Name.Local != "" {
+ start.Attr = append(start.Attr, attr)
+ }
+ continue
+ }
+
+ if fv.CanAddr() {
+ pv := fv.Addr()
+ if pv.CanInterface() && pv.Type().Implements(marshalerAttrType) {
+ attr, err := pv.Interface().(MarshalerAttr).MarshalXMLAttr(name)
+ if err != nil {
+ return err
+ }
+ if attr.Name.Local != "" {
+ start.Attr = append(start.Attr, attr)
+ }
+ continue
+ }
+ }
+
+ if fv.CanInterface() && fv.Type().Implements(textMarshalerType) {
+ text, err := fv.Interface().(encoding.TextMarshaler).MarshalText()
+ if err != nil {
+ return err
+ }
+ start.Attr = append(start.Attr, Attr{name, string(text)})
+ continue
+ }
+
+ if fv.CanAddr() {
+ pv := fv.Addr()
+ if pv.CanInterface() && pv.Type().Implements(textMarshalerType) {
+ text, err := pv.Interface().(encoding.TextMarshaler).MarshalText()
+ if err != nil {
+ return err
+ }
+ start.Attr = append(start.Attr, Attr{name, string(text)})
+ continue
+ }
+ }
+
+ // Dereference or skip nil pointer, interface values.
+ switch fv.Kind() {
+ case reflect.Ptr, reflect.Interface:
+ if fv.IsNil() {
+ continue
+ }
+ fv = fv.Elem()
+ }
+
+ s, b, err := p.marshalSimple(fv.Type(), fv)
+ if err != nil {
+ return err
+ }
+ if b != nil {
+ s = string(b)
+ }
+ start.Attr = append(start.Attr, Attr{name, s})
+ }
+
+ if err := p.writeStart(&start); err != nil {
+ return err
+ }
+
+ if val.Kind() == reflect.Struct {
+ err = p.marshalStruct(tinfo, val)
+ } else {
+ s, b, err1 := p.marshalSimple(typ, val)
+ if err1 != nil {
+ err = err1
+ } else if b != nil {
+ EscapeText(p, b)
+ } else {
+ p.EscapeString(s)
+ }
+ }
+ if err != nil {
+ return err
+ }
+
+ if err := p.writeEnd(start.Name); err != nil {
+ return err
+ }
+
+ return p.cachedWriteError()
+}
+
+// defaultStart returns the default start element to use,
+// given the reflect type, field info, and start template.
+func defaultStart(typ reflect.Type, finfo *fieldInfo, startTemplate *StartElement) StartElement {
+ var start StartElement
+ // Precedence for the XML element name is as above,
+ // except that we do not look inside structs for the first field.
+ if startTemplate != nil {
+ start.Name = startTemplate.Name
+ start.Attr = append(start.Attr, startTemplate.Attr...)
+ } else if finfo != nil && finfo.name != "" {
+ start.Name.Local = finfo.name
+ start.Name.Space = finfo.xmlns
+ } else if typ.Name() != "" {
+ start.Name.Local = typ.Name()
+ } else {
+ // Must be a pointer to a named type,
+ // since it has the Marshaler methods.
+ start.Name.Local = typ.Elem().Name()
+ }
+ return start
+}
+
+// marshalInterface marshals a Marshaler interface value.
+func (p *printer) marshalInterface(val Marshaler, start StartElement) error {
+ // Push a marker onto the tag stack so that MarshalXML
+ // cannot close the XML tags that it did not open.
+ p.tags = append(p.tags, Name{})
+ n := len(p.tags)
+
+ err := val.MarshalXML(p.encoder, start)
+ if err != nil {
+ return err
+ }
+
+ // Make sure MarshalXML closed all its tags. p.tags[n-1] is the mark.
+ if len(p.tags) > n {
+ return fmt.Errorf("xml: %s.MarshalXML wrote invalid XML: <%s> not closed", receiverType(val), p.tags[len(p.tags)-1].Local)
+ }
+ p.tags = p.tags[:n-1]
+ return nil
+}
+
+// marshalTextInterface marshals a TextMarshaler interface value.
+func (p *printer) marshalTextInterface(val encoding.TextMarshaler, start StartElement) error {
+ if err := p.writeStart(&start); err != nil {
+ return err
+ }
+ text, err := val.MarshalText()
+ if err != nil {
+ return err
+ }
+ EscapeText(p, text)
+ return p.writeEnd(start.Name)
+}
+
+// writeStart writes the given start element.
+func (p *printer) writeStart(start *StartElement) error {
+ if start.Name.Local == "" {
+ return fmt.Errorf("xml: start tag with no name")
+ }
+
+ p.tags = append(p.tags, start.Name)
+ p.markPrefix()
+
+ p.writeIndent(1)
+ p.WriteByte('<')
+ p.WriteString(start.Name.Local)
+
+ if start.Name.Space != "" {
+ p.WriteString(` xmlns="`)
+ p.EscapeString(start.Name.Space)
+ p.WriteByte('"')
+ }
+
+ // Attributes
+ for _, attr := range start.Attr {
+ name := attr.Name
+ if name.Local == "" {
+ continue
+ }
+ p.WriteByte(' ')
+ if name.Space != "" {
+ p.WriteString(p.createAttrPrefix(name.Space))
+ p.WriteByte(':')
+ }
+ p.WriteString(name.Local)
+ p.WriteString(`="`)
+ p.EscapeString(attr.Value)
+ p.WriteByte('"')
+ }
+ p.WriteByte('>')
+ return nil
+}
+
+func (p *printer) writeEnd(name Name) error {
+ if name.Local == "" {
+ return fmt.Errorf("xml: end tag with no name")
+ }
+ if len(p.tags) == 0 || p.tags[len(p.tags)-1].Local == "" {
+ return fmt.Errorf("xml: end tag </%s> without start tag", name.Local)
+ }
+ if top := p.tags[len(p.tags)-1]; top != name {
+ if top.Local != name.Local {
+ return fmt.Errorf("xml: end tag </%s> does not match start tag <%s>", name.Local, top.Local)
+ }
+ return fmt.Errorf("xml: end tag </%s> in namespace %s does not match start tag <%s> in namespace %s", name.Local, name.Space, top.Local, top.Space)
+ }
+ p.tags = p.tags[:len(p.tags)-1]
+
+ p.writeIndent(-1)
+ p.WriteByte('<')
+ p.WriteByte('/')
+ p.WriteString(name.Local)
+ p.WriteByte('>')
+ p.popPrefix()
+ return nil
+}
+
+func (p *printer) marshalSimple(typ reflect.Type, val reflect.Value) (string, []byte, error) {
+ switch val.Kind() {
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return strconv.FormatInt(val.Int(), 10), nil, nil
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return strconv.FormatUint(val.Uint(), 10), nil, nil
+ case reflect.Float32, reflect.Float64:
+ return strconv.FormatFloat(val.Float(), 'g', -1, val.Type().Bits()), nil, nil
+ case reflect.String:
+ return val.String(), nil, nil
+ case reflect.Bool:
+ return strconv.FormatBool(val.Bool()), nil, nil
+ case reflect.Array:
+ if typ.Elem().Kind() != reflect.Uint8 {
+ break
+ }
+ // [...]byte
+ var bytes []byte
+ if val.CanAddr() {
+ bytes = val.Slice(0, val.Len()).Bytes()
+ } else {
+ bytes = make([]byte, val.Len())
+ reflect.Copy(reflect.ValueOf(bytes), val)
+ }
+ return "", bytes, nil
+ case reflect.Slice:
+ if typ.Elem().Kind() != reflect.Uint8 {
+ break
+ }
+ // []byte
+ return "", val.Bytes(), nil
+ }
+ return "", nil, &UnsupportedTypeError{typ}
+}
+
+var ddBytes = []byte("--")
+
+func (p *printer) marshalStruct(tinfo *typeInfo, val reflect.Value) error {
+ s := parentStack{p: p}
+ for i := range tinfo.fields {
+ finfo := &tinfo.fields[i]
+ if finfo.flags&fAttr != 0 {
+ continue
+ }
+ vf := finfo.value(val)
+
+ // Dereference or skip nil pointer, interface values.
+ switch vf.Kind() {
+ case reflect.Ptr, reflect.Interface:
+ if !vf.IsNil() {
+ vf = vf.Elem()
+ }
+ }
+
+ switch finfo.flags & fMode {
+ case fCharData:
+ if vf.CanInterface() && vf.Type().Implements(textMarshalerType) {
+ data, err := vf.Interface().(encoding.TextMarshaler).MarshalText()
+ if err != nil {
+ return err
+ }
+ Escape(p, data)
+ continue
+ }
+ if vf.CanAddr() {
+ pv := vf.Addr()
+ if pv.CanInterface() && pv.Type().Implements(textMarshalerType) {
+ data, err := pv.Interface().(encoding.TextMarshaler).MarshalText()
+ if err != nil {
+ return err
+ }
+ Escape(p, data)
+ continue
+ }
+ }
+ var scratch [64]byte
+ switch vf.Kind() {
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ Escape(p, strconv.AppendInt(scratch[:0], vf.Int(), 10))
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ Escape(p, strconv.AppendUint(scratch[:0], vf.Uint(), 10))
+ case reflect.Float32, reflect.Float64:
+ Escape(p, strconv.AppendFloat(scratch[:0], vf.Float(), 'g', -1, vf.Type().Bits()))
+ case reflect.Bool:
+ Escape(p, strconv.AppendBool(scratch[:0], vf.Bool()))
+ case reflect.String:
+ if err := EscapeText(p, []byte(vf.String())); err != nil {
+ return err
+ }
+ case reflect.Slice:
+ if elem, ok := vf.Interface().([]byte); ok {
+ if err := EscapeText(p, elem); err != nil {
+ return err
+ }
+ }
+ }
+ continue
+
+ case fComment:
+ k := vf.Kind()
+ if !(k == reflect.String || k == reflect.Slice && vf.Type().Elem().Kind() == reflect.Uint8) {
+ return fmt.Errorf("xml: bad type for comment field of %s", val.Type())
+ }
+ if vf.Len() == 0 {
+ continue
+ }
+ p.writeIndent(0)
+ p.WriteString("<!--")
+ dashDash := false
+ dashLast := false
+ switch k {
+ case reflect.String:
+ s := vf.String()
+ dashDash = strings.Index(s, "--") >= 0
+ dashLast = s[len(s)-1] == '-'
+ if !dashDash {
+ p.WriteString(s)
+ }
+ case reflect.Slice:
+ b := vf.Bytes()
+ dashDash = bytes.Index(b, ddBytes) >= 0
+ dashLast = b[len(b)-1] == '-'
+ if !dashDash {
+ p.Write(b)
+ }
+ default:
+ panic("can't happen")
+ }
+ if dashDash {
+ return fmt.Errorf(`xml: comments must not contain "--"`)
+ }
+ if dashLast {
+ // "--->" is invalid grammar. Make it "- -->"
+ p.WriteByte(' ')
+ }
+ p.WriteString("-->")
+ continue
+
+ case fInnerXml:
+ iface := vf.Interface()
+ switch raw := iface.(type) {
+ case []byte:
+ p.Write(raw)
+ continue
+ case string:
+ p.WriteString(raw)
+ continue
+ }
+
+ case fElement, fElement | fAny:
+ if err := s.trim(finfo.parents); err != nil {
+ return err
+ }
+ if len(finfo.parents) > len(s.stack) {
+ if vf.Kind() != reflect.Ptr && vf.Kind() != reflect.Interface || !vf.IsNil() {
+ if err := s.push(finfo.parents[len(s.stack):]); err != nil {
+ return err
+ }
+ }
+ }
+ }
+ if err := p.marshalValue(vf, finfo, nil); err != nil {
+ return err
+ }
+ }
+ s.trim(nil)
+ return p.cachedWriteError()
+}
+
+// return the bufio Writer's cached write error
+func (p *printer) cachedWriteError() error {
+ _, err := p.Write(nil)
+ return err
+}
+
+func (p *printer) writeIndent(depthDelta int) {
+ if len(p.prefix) == 0 && len(p.indent) == 0 {
+ return
+ }
+ if depthDelta < 0 {
+ p.depth--
+ if p.indentedIn {
+ p.indentedIn = false
+ return
+ }
+ p.indentedIn = false
+ }
+ if p.putNewline {
+ p.WriteByte('\n')
+ } else {
+ p.putNewline = true
+ }
+ if len(p.prefix) > 0 {
+ p.WriteString(p.prefix)
+ }
+ if len(p.indent) > 0 {
+ for i := 0; i < p.depth; i++ {
+ p.WriteString(p.indent)
+ }
+ }
+ if depthDelta > 0 {
+ p.depth++
+ p.indentedIn = true
+ }
+}
+
+type parentStack struct {
+ p *printer
+ stack []string
+}
+
+// trim updates the XML context to match the longest common prefix of the stack
+// and the given parents. A closing tag will be written for every parent
+// popped. Passing a zero slice or nil will close all the elements.
+func (s *parentStack) trim(parents []string) error {
+ split := 0
+ for ; split < len(parents) && split < len(s.stack); split++ {
+ if parents[split] != s.stack[split] {
+ break
+ }
+ }
+ for i := len(s.stack) - 1; i >= split; i-- {
+ if err := s.p.writeEnd(Name{Local: s.stack[i]}); err != nil {
+ return err
+ }
+ }
+ s.stack = parents[:split]
+ return nil
+}
+
+// push adds parent elements to the stack and writes open tags.
+func (s *parentStack) push(parents []string) error {
+ for i := 0; i < len(parents); i++ {
+ if err := s.p.writeStart(&StartElement{Name: Name{Local: parents[i]}}); err != nil {
+ return err
+ }
+ }
+ s.stack = append(s.stack, parents...)
+ return nil
+}
+
+// A MarshalXMLError is returned when Marshal encounters a type
+// that cannot be converted into XML.
+type UnsupportedTypeError struct {
+ Type reflect.Type
+}
+
+func (e *UnsupportedTypeError) Error() string {
+ return "xml: unsupported type: " + e.Type.String()
+}
+
+func isEmptyValue(v reflect.Value) bool {
+ switch v.Kind() {
+ case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+ return v.Len() == 0
+ case reflect.Bool:
+ return !v.Bool()
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return v.Int() == 0
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return v.Uint() == 0
+ case reflect.Float32, reflect.Float64:
+ return v.Float() == 0
+ case reflect.Interface, reflect.Ptr:
+ return v.IsNil()
+ }
+ return false
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-03 06:59:48 +0000