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-rw-r--r--vendor/gopkg.in/yaml.v3/decode.go931
1 files changed, 931 insertions, 0 deletions
diff --git a/vendor/gopkg.in/yaml.v3/decode.go b/vendor/gopkg.in/yaml.v3/decode.go
new file mode 100644
index 00000000..be63169b
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v3/decode.go
@@ -0,0 +1,931 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+ "encoding"
+ "encoding/base64"
+ "fmt"
+ "io"
+ "math"
+ "reflect"
+ "strconv"
+ "time"
+)
+
+// ----------------------------------------------------------------------------
+// Parser, produces a node tree out of a libyaml event stream.
+
+type parser struct {
+ parser yaml_parser_t
+ event yaml_event_t
+ doc *Node
+ anchors map[string]*Node
+ doneInit bool
+}
+
+func newParser(b []byte) *parser {
+ p := parser{}
+ if !yaml_parser_initialize(&p.parser) {
+ panic("failed to initialize YAML emitter")
+ }
+ if len(b) == 0 {
+ b = []byte{'\n'}
+ }
+ yaml_parser_set_input_string(&p.parser, b)
+ return &p
+}
+
+func newParserFromReader(r io.Reader) *parser {
+ p := parser{}
+ if !yaml_parser_initialize(&p.parser) {
+ panic("failed to initialize YAML emitter")
+ }
+ yaml_parser_set_input_reader(&p.parser, r)
+ return &p
+}
+
+func (p *parser) init() {
+ if p.doneInit {
+ return
+ }
+ p.anchors = make(map[string]*Node)
+ p.expect(yaml_STREAM_START_EVENT)
+ p.doneInit = true
+}
+
+func (p *parser) destroy() {
+ if p.event.typ != yaml_NO_EVENT {
+ yaml_event_delete(&p.event)
+ }
+ yaml_parser_delete(&p.parser)
+}
+
+// expect consumes an event from the event stream and
+// checks that it's of the expected type.
+func (p *parser) expect(e yaml_event_type_t) {
+ if p.event.typ == yaml_NO_EVENT {
+ if !yaml_parser_parse(&p.parser, &p.event) {
+ p.fail()
+ }
+ }
+ if p.event.typ == yaml_STREAM_END_EVENT {
+ failf("attempted to go past the end of stream; corrupted value?")
+ }
+ if p.event.typ != e {
+ p.parser.problem = fmt.Sprintf("expected %s event but got %s", e, p.event.typ)
+ p.fail()
+ }
+ yaml_event_delete(&p.event)
+ p.event.typ = yaml_NO_EVENT
+}
+
+// peek peeks at the next event in the event stream,
+// puts the results into p.event and returns the event type.
+func (p *parser) peek() yaml_event_type_t {
+ if p.event.typ != yaml_NO_EVENT {
+ return p.event.typ
+ }
+ if !yaml_parser_parse(&p.parser, &p.event) {
+ p.fail()
+ }
+ return p.event.typ
+}
+
+func (p *parser) fail() {
+ var where string
+ var line int
+ if p.parser.problem_mark.line != 0 {
+ line = p.parser.problem_mark.line
+ // Scanner errors don't iterate line before returning error
+ if p.parser.error == yaml_SCANNER_ERROR {
+ line++
+ }
+ } else if p.parser.context_mark.line != 0 {
+ line = p.parser.context_mark.line
+ }
+ if line != 0 {
+ where = "line " + strconv.Itoa(line) + ": "
+ }
+ var msg string
+ if len(p.parser.problem) > 0 {
+ msg = p.parser.problem
+ } else {
+ msg = "unknown problem parsing YAML content"
+ }
+ failf("%s%s", where, msg)
+}
+
+func (p *parser) anchor(n *Node, anchor []byte) {
+ if anchor != nil {
+ n.Anchor = string(anchor)
+ p.anchors[n.Anchor] = n
+ }
+}
+
+func (p *parser) parse() *Node {
+ p.init()
+ switch p.peek() {
+ case yaml_SCALAR_EVENT:
+ return p.scalar()
+ case yaml_ALIAS_EVENT:
+ return p.alias()
+ case yaml_MAPPING_START_EVENT:
+ return p.mapping()
+ case yaml_SEQUENCE_START_EVENT:
+ return p.sequence()
+ case yaml_DOCUMENT_START_EVENT:
+ return p.document()
+ case yaml_STREAM_END_EVENT:
+ // Happens when attempting to decode an empty buffer.
+ return nil
+ case yaml_TAIL_COMMENT_EVENT:
+ panic("internal error: unexpected tail comment event (please report)")
+ default:
+ panic("internal error: attempted to parse unknown event (please report): " + p.event.typ.String())
+ }
+}
+
+func (p *parser) node(kind Kind, defaultTag, tag, value string) *Node {
+ var style Style
+ if tag != "" && tag != "!" {
+ tag = shortTag(tag)
+ style = TaggedStyle
+ } else if defaultTag != "" {
+ tag = defaultTag
+ } else if kind == ScalarNode {
+ tag, _ = resolve("", value)
+ }
+ return &Node{
+ Kind: kind,
+ Tag: tag,
+ Value: value,
+ Style: style,
+ Line: p.event.start_mark.line + 1,
+ Column: p.event.start_mark.column + 1,
+ HeadComment: string(p.event.head_comment),
+ LineComment: string(p.event.line_comment),
+ FootComment: string(p.event.foot_comment),
+ }
+}
+
+func (p *parser) parseChild(parent *Node) *Node {
+ child := p.parse()
+ parent.Content = append(parent.Content, child)
+ return child
+}
+
+func (p *parser) document() *Node {
+ n := p.node(DocumentNode, "", "", "")
+ p.doc = n
+ p.expect(yaml_DOCUMENT_START_EVENT)
+ p.parseChild(n)
+ if p.peek() == yaml_DOCUMENT_END_EVENT {
+ n.FootComment = string(p.event.foot_comment)
+ }
+ p.expect(yaml_DOCUMENT_END_EVENT)
+ return n
+}
+
+func (p *parser) alias() *Node {
+ n := p.node(AliasNode, "", "", string(p.event.anchor))
+ n.Alias = p.anchors[n.Value]
+ if n.Alias == nil {
+ failf("unknown anchor '%s' referenced", n.Value)
+ }
+ p.expect(yaml_ALIAS_EVENT)
+ return n
+}
+
+func (p *parser) scalar() *Node {
+ var parsedStyle = p.event.scalar_style()
+ var nodeStyle Style
+ switch {
+ case parsedStyle&yaml_DOUBLE_QUOTED_SCALAR_STYLE != 0:
+ nodeStyle = DoubleQuotedStyle
+ case parsedStyle&yaml_SINGLE_QUOTED_SCALAR_STYLE != 0:
+ nodeStyle = SingleQuotedStyle
+ case parsedStyle&yaml_LITERAL_SCALAR_STYLE != 0:
+ nodeStyle = LiteralStyle
+ case parsedStyle&yaml_FOLDED_SCALAR_STYLE != 0:
+ nodeStyle = FoldedStyle
+ }
+ var nodeValue = string(p.event.value)
+ var nodeTag = string(p.event.tag)
+ var defaultTag string
+ if nodeStyle == 0 {
+ if nodeValue == "<<" {
+ defaultTag = mergeTag
+ }
+ } else {
+ defaultTag = strTag
+ }
+ n := p.node(ScalarNode, defaultTag, nodeTag, nodeValue)
+ n.Style |= nodeStyle
+ p.anchor(n, p.event.anchor)
+ p.expect(yaml_SCALAR_EVENT)
+ return n
+}
+
+func (p *parser) sequence() *Node {
+ n := p.node(SequenceNode, seqTag, string(p.event.tag), "")
+ if p.event.sequence_style()&yaml_FLOW_SEQUENCE_STYLE != 0 {
+ n.Style |= FlowStyle
+ }
+ p.anchor(n, p.event.anchor)
+ p.expect(yaml_SEQUENCE_START_EVENT)
+ for p.peek() != yaml_SEQUENCE_END_EVENT {
+ p.parseChild(n)
+ }
+ n.LineComment = string(p.event.line_comment)
+ n.FootComment = string(p.event.foot_comment)
+ p.expect(yaml_SEQUENCE_END_EVENT)
+ return n
+}
+
+func (p *parser) mapping() *Node {
+ n := p.node(MappingNode, mapTag, string(p.event.tag), "")
+ block := true
+ if p.event.mapping_style()&yaml_FLOW_MAPPING_STYLE != 0 {
+ block = false
+ n.Style |= FlowStyle
+ }
+ p.anchor(n, p.event.anchor)
+ p.expect(yaml_MAPPING_START_EVENT)
+ for p.peek() != yaml_MAPPING_END_EVENT {
+ k := p.parseChild(n)
+ if block && k.FootComment != "" {
+ // Must be a foot comment for the prior value when being dedented.
+ if len(n.Content) > 2 {
+ n.Content[len(n.Content)-3].FootComment = k.FootComment
+ k.FootComment = ""
+ }
+ }
+ v := p.parseChild(n)
+ if k.FootComment == "" && v.FootComment != "" {
+ k.FootComment = v.FootComment
+ v.FootComment = ""
+ }
+ if p.peek() == yaml_TAIL_COMMENT_EVENT {
+ if k.FootComment == "" {
+ k.FootComment = string(p.event.foot_comment)
+ }
+ p.expect(yaml_TAIL_COMMENT_EVENT)
+ }
+ }
+ n.LineComment = string(p.event.line_comment)
+ n.FootComment = string(p.event.foot_comment)
+ if n.Style&FlowStyle == 0 && n.FootComment != "" && len(n.Content) > 1 {
+ n.Content[len(n.Content)-2].FootComment = n.FootComment
+ n.FootComment = ""
+ }
+ p.expect(yaml_MAPPING_END_EVENT)
+ return n
+}
+
+// ----------------------------------------------------------------------------
+// Decoder, unmarshals a node into a provided value.
+
+type decoder struct {
+ doc *Node
+ aliases map[*Node]bool
+ terrors []string
+
+ stringMapType reflect.Type
+ generalMapType reflect.Type
+
+ knownFields bool
+ uniqueKeys bool
+ decodeCount int
+ aliasCount int
+ aliasDepth int
+}
+
+var (
+ nodeType = reflect.TypeOf(Node{})
+ durationType = reflect.TypeOf(time.Duration(0))
+ stringMapType = reflect.TypeOf(map[string]interface{}{})
+ generalMapType = reflect.TypeOf(map[interface{}]interface{}{})
+ ifaceType = generalMapType.Elem()
+ timeType = reflect.TypeOf(time.Time{})
+ ptrTimeType = reflect.TypeOf(&time.Time{})
+)
+
+func newDecoder() *decoder {
+ d := &decoder{
+ stringMapType: stringMapType,
+ generalMapType: generalMapType,
+ uniqueKeys: true,
+ }
+ d.aliases = make(map[*Node]bool)
+ return d
+}
+
+func (d *decoder) terror(n *Node, tag string, out reflect.Value) {
+ if n.Tag != "" {
+ tag = n.Tag
+ }
+ value := n.Value
+ if tag != seqTag && tag != mapTag {
+ if len(value) > 10 {
+ value = " `" + value[:7] + "...`"
+ } else {
+ value = " `" + value + "`"
+ }
+ }
+ d.terrors = append(d.terrors, fmt.Sprintf("line %d: cannot unmarshal %s%s into %s", n.Line, shortTag(tag), value, out.Type()))
+}
+
+func (d *decoder) callUnmarshaler(n *Node, u Unmarshaler) (good bool) {
+ err := u.UnmarshalYAML(n)
+ if e, ok := err.(*TypeError); ok {
+ d.terrors = append(d.terrors, e.Errors...)
+ return false
+ }
+ if err != nil {
+ fail(err)
+ }
+ return true
+}
+
+func (d *decoder) callObsoleteUnmarshaler(n *Node, u obsoleteUnmarshaler) (good bool) {
+ terrlen := len(d.terrors)
+ err := u.UnmarshalYAML(func(v interface{}) (err error) {
+ defer handleErr(&err)
+ d.unmarshal(n, reflect.ValueOf(v))
+ if len(d.terrors) > terrlen {
+ issues := d.terrors[terrlen:]
+ d.terrors = d.terrors[:terrlen]
+ return &TypeError{issues}
+ }
+ return nil
+ })
+ if e, ok := err.(*TypeError); ok {
+ d.terrors = append(d.terrors, e.Errors...)
+ return false
+ }
+ if err != nil {
+ fail(err)
+ }
+ return true
+}
+
+// d.prepare initializes and dereferences pointers and calls UnmarshalYAML
+// if a value is found to implement it.
+// It returns the initialized and dereferenced out value, whether
+// unmarshalling was already done by UnmarshalYAML, and if so whether
+// its types unmarshalled appropriately.
+//
+// If n holds a null value, prepare returns before doing anything.
+func (d *decoder) prepare(n *Node, out reflect.Value) (newout reflect.Value, unmarshaled, good bool) {
+ if n.ShortTag() == nullTag {
+ return out, false, false
+ }
+ again := true
+ for again {
+ again = false
+ if out.Kind() == reflect.Ptr {
+ if out.IsNil() {
+ out.Set(reflect.New(out.Type().Elem()))
+ }
+ out = out.Elem()
+ again = true
+ }
+ if out.CanAddr() {
+ outi := out.Addr().Interface()
+ if u, ok := outi.(Unmarshaler); ok {
+ good = d.callUnmarshaler(n, u)
+ return out, true, good
+ }
+ if u, ok := outi.(obsoleteUnmarshaler); ok {
+ good = d.callObsoleteUnmarshaler(n, u)
+ return out, true, good
+ }
+ }
+ }
+ return out, false, false
+}
+
+func (d *decoder) fieldByIndex(n *Node, v reflect.Value, index []int) (field reflect.Value) {
+ if n.ShortTag() == nullTag {
+ return reflect.Value{}
+ }
+ for _, num := range index {
+ for {
+ if v.Kind() == reflect.Ptr {
+ if v.IsNil() {
+ v.Set(reflect.New(v.Type().Elem()))
+ }
+ v = v.Elem()
+ continue
+ }
+ break
+ }
+ v = v.Field(num)
+ }
+ return v
+}
+
+const (
+ // 400,000 decode operations is ~500kb of dense object declarations, or
+ // ~5kb of dense object declarations with 10000% alias expansion
+ alias_ratio_range_low = 400000
+
+ // 4,000,000 decode operations is ~5MB of dense object declarations, or
+ // ~4.5MB of dense object declarations with 10% alias expansion
+ alias_ratio_range_high = 4000000
+
+ // alias_ratio_range is the range over which we scale allowed alias ratios
+ alias_ratio_range = float64(alias_ratio_range_high - alias_ratio_range_low)
+)
+
+func allowedAliasRatio(decodeCount int) float64 {
+ switch {
+ case decodeCount <= alias_ratio_range_low:
+ // allow 99% to come from alias expansion for small-to-medium documents
+ return 0.99
+ case decodeCount >= alias_ratio_range_high:
+ // allow 10% to come from alias expansion for very large documents
+ return 0.10
+ default:
+ // scale smoothly from 99% down to 10% over the range.
+ // this maps to 396,000 - 400,000 allowed alias-driven decodes over the range.
+ // 400,000 decode operations is ~100MB of allocations in worst-case scenarios (single-item maps).
+ return 0.99 - 0.89*(float64(decodeCount-alias_ratio_range_low)/alias_ratio_range)
+ }
+}
+
+func (d *decoder) unmarshal(n *Node, out reflect.Value) (good bool) {
+ d.decodeCount++
+ if d.aliasDepth > 0 {
+ d.aliasCount++
+ }
+ if d.aliasCount > 100 && d.decodeCount > 1000 && float64(d.aliasCount)/float64(d.decodeCount) > allowedAliasRatio(d.decodeCount) {
+ failf("document contains excessive aliasing")
+ }
+ if out.Type() == nodeType {
+ out.Set(reflect.ValueOf(n).Elem())
+ return true
+ }
+ switch n.Kind {
+ case DocumentNode:
+ return d.document(n, out)
+ case AliasNode:
+ return d.alias(n, out)
+ }
+ out, unmarshaled, good := d.prepare(n, out)
+ if unmarshaled {
+ return good
+ }
+ switch n.Kind {
+ case ScalarNode:
+ good = d.scalar(n, out)
+ case MappingNode:
+ good = d.mapping(n, out)
+ case SequenceNode:
+ good = d.sequence(n, out)
+ default:
+ panic("internal error: unknown node kind: " + strconv.Itoa(int(n.Kind)))
+ }
+ return good
+}
+
+func (d *decoder) document(n *Node, out reflect.Value) (good bool) {
+ if len(n.Content) == 1 {
+ d.doc = n
+ d.unmarshal(n.Content[0], out)
+ return true
+ }
+ return false
+}
+
+func (d *decoder) alias(n *Node, out reflect.Value) (good bool) {
+ if d.aliases[n] {
+ // TODO this could actually be allowed in some circumstances.
+ failf("anchor '%s' value contains itself", n.Value)
+ }
+ d.aliases[n] = true
+ d.aliasDepth++
+ good = d.unmarshal(n.Alias, out)
+ d.aliasDepth--
+ delete(d.aliases, n)
+ return good
+}
+
+var zeroValue reflect.Value
+
+func resetMap(out reflect.Value) {
+ for _, k := range out.MapKeys() {
+ out.SetMapIndex(k, zeroValue)
+ }
+}
+
+func (d *decoder) scalar(n *Node, out reflect.Value) bool {
+ var tag string
+ var resolved interface{}
+ if n.indicatedString() {
+ tag = strTag
+ resolved = n.Value
+ } else {
+ tag, resolved = resolve(n.Tag, n.Value)
+ if tag == binaryTag {
+ data, err := base64.StdEncoding.DecodeString(resolved.(string))
+ if err != nil {
+ failf("!!binary value contains invalid base64 data")
+ }
+ resolved = string(data)
+ }
+ }
+ if resolved == nil {
+ if out.CanAddr() {
+ switch out.Kind() {
+ case reflect.Interface, reflect.Ptr, reflect.Map, reflect.Slice:
+ out.Set(reflect.Zero(out.Type()))
+ return true
+ }
+ }
+ return false
+ }
+ if resolvedv := reflect.ValueOf(resolved); out.Type() == resolvedv.Type() {
+ // We've resolved to exactly the type we want, so use that.
+ out.Set(resolvedv)
+ return true
+ }
+ // Perhaps we can use the value as a TextUnmarshaler to
+ // set its value.
+ if out.CanAddr() {
+ u, ok := out.Addr().Interface().(encoding.TextUnmarshaler)
+ if ok {
+ var text []byte
+ if tag == binaryTag {
+ text = []byte(resolved.(string))
+ } else {
+ // We let any value be unmarshaled into TextUnmarshaler.
+ // That might be more lax than we'd like, but the
+ // TextUnmarshaler itself should bowl out any dubious values.
+ text = []byte(n.Value)
+ }
+ err := u.UnmarshalText(text)
+ if err != nil {
+ fail(err)
+ }
+ return true
+ }
+ }
+ switch out.Kind() {
+ case reflect.String:
+ if tag == binaryTag {
+ out.SetString(resolved.(string))
+ return true
+ }
+ out.SetString(n.Value)
+ return true
+ case reflect.Interface:
+ out.Set(reflect.ValueOf(resolved))
+ return true
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ // This used to work in v2, but it's very unfriendly.
+ isDuration := out.Type() == durationType
+
+ switch resolved := resolved.(type) {
+ case int:
+ if !isDuration && !out.OverflowInt(int64(resolved)) {
+ out.SetInt(int64(resolved))
+ return true
+ }
+ case int64:
+ if !isDuration && !out.OverflowInt(resolved) {
+ out.SetInt(resolved)
+ return true
+ }
+ case uint64:
+ if !isDuration && resolved <= math.MaxInt64 && !out.OverflowInt(int64(resolved)) {
+ out.SetInt(int64(resolved))
+ return true
+ }
+ case float64:
+ if !isDuration && resolved <= math.MaxInt64 && !out.OverflowInt(int64(resolved)) {
+ out.SetInt(int64(resolved))
+ return true
+ }
+ case string:
+ if out.Type() == durationType {
+ d, err := time.ParseDuration(resolved)
+ if err == nil {
+ out.SetInt(int64(d))
+ return true
+ }
+ }
+ }
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ switch resolved := resolved.(type) {
+ case int:
+ if resolved >= 0 && !out.OverflowUint(uint64(resolved)) {
+ out.SetUint(uint64(resolved))
+ return true
+ }
+ case int64:
+ if resolved >= 0 && !out.OverflowUint(uint64(resolved)) {
+ out.SetUint(uint64(resolved))
+ return true
+ }
+ case uint64:
+ if !out.OverflowUint(uint64(resolved)) {
+ out.SetUint(uint64(resolved))
+ return true
+ }
+ case float64:
+ if resolved <= math.MaxUint64 && !out.OverflowUint(uint64(resolved)) {
+ out.SetUint(uint64(resolved))
+ return true
+ }
+ }
+ case reflect.Bool:
+ switch resolved := resolved.(type) {
+ case bool:
+ out.SetBool(resolved)
+ return true
+ case string:
+ // This offers some compatibility with the 1.1 spec (https://yaml.org/type/bool.html).
+ // It only works if explicitly attempting to unmarshal into a typed bool value.
+ switch resolved {
+ case "y", "Y", "yes", "Yes", "YES", "on", "On", "ON":
+ out.SetBool(true)
+ return true
+ case "n", "N", "no", "No", "NO", "off", "Off", "OFF":
+ out.SetBool(false)
+ return true
+ }
+ }
+ case reflect.Float32, reflect.Float64:
+ switch resolved := resolved.(type) {
+ case int:
+ out.SetFloat(float64(resolved))
+ return true
+ case int64:
+ out.SetFloat(float64(resolved))
+ return true
+ case uint64:
+ out.SetFloat(float64(resolved))
+ return true
+ case float64:
+ out.SetFloat(resolved)
+ return true
+ }
+ case reflect.Struct:
+ if resolvedv := reflect.ValueOf(resolved); out.Type() == resolvedv.Type() {
+ out.Set(resolvedv)
+ return true
+ }
+ case reflect.Ptr:
+ panic("yaml internal error: please report the issue")
+ }
+ d.terror(n, tag, out)
+ return false
+}
+
+func settableValueOf(i interface{}) reflect.Value {
+ v := reflect.ValueOf(i)
+ sv := reflect.New(v.Type()).Elem()
+ sv.Set(v)
+ return sv
+}
+
+func (d *decoder) sequence(n *Node, out reflect.Value) (good bool) {
+ l := len(n.Content)
+
+ var iface reflect.Value
+ switch out.Kind() {
+ case reflect.Slice:
+ out.Set(reflect.MakeSlice(out.Type(), l, l))
+ case reflect.Array:
+ if l != out.Len() {
+ failf("invalid array: want %d elements but got %d", out.Len(), l)
+ }
+ case reflect.Interface:
+ // No type hints. Will have to use a generic sequence.
+ iface = out
+ out = settableValueOf(make([]interface{}, l))
+ default:
+ d.terror(n, seqTag, out)
+ return false
+ }
+ et := out.Type().Elem()
+
+ j := 0
+ for i := 0; i < l; i++ {
+ e := reflect.New(et).Elem()
+ if ok := d.unmarshal(n.Content[i], e); ok {
+ out.Index(j).Set(e)
+ j++
+ }
+ }
+ if out.Kind() != reflect.Array {
+ out.Set(out.Slice(0, j))
+ }
+ if iface.IsValid() {
+ iface.Set(out)
+ }
+ return true
+}
+
+func (d *decoder) mapping(n *Node, out reflect.Value) (good bool) {
+ l := len(n.Content)
+ if d.uniqueKeys {
+ nerrs := len(d.terrors)
+ for i := 0; i < l; i += 2 {
+ ni := n.Content[i]
+ for j := i + 2; j < l; j += 2 {
+ nj := n.Content[j]
+ if ni.Kind == nj.Kind && ni.Value == nj.Value {
+ d.terrors = append(d.terrors, fmt.Sprintf("line %d: mapping key %#v already defined at line %d", nj.Line, nj.Value, ni.Line))
+ }
+ }
+ }
+ if len(d.terrors) > nerrs {
+ return false
+ }
+ }
+ switch out.Kind() {
+ case reflect.Struct:
+ return d.mappingStruct(n, out)
+ case reflect.Map:
+ // okay
+ case reflect.Interface:
+ iface := out
+ if isStringMap(n) {
+ out = reflect.MakeMap(d.stringMapType)
+ } else {
+ out = reflect.MakeMap(d.generalMapType)
+ }
+ iface.Set(out)
+ default:
+ d.terror(n, mapTag, out)
+ return false
+ }
+
+ outt := out.Type()
+ kt := outt.Key()
+ et := outt.Elem()
+
+ stringMapType := d.stringMapType
+ generalMapType := d.generalMapType
+ if outt.Elem() == ifaceType {
+ if outt.Key().Kind() == reflect.String {
+ d.stringMapType = outt
+ } else if outt.Key() == ifaceType {
+ d.generalMapType = outt
+ }
+ }
+
+ if out.IsNil() {
+ out.Set(reflect.MakeMap(outt))
+ }
+ for i := 0; i < l; i += 2 {
+ if isMerge(n.Content[i]) {
+ d.merge(n.Content[i+1], out)
+ continue
+ }
+ k := reflect.New(kt).Elem()
+ if d.unmarshal(n.Content[i], k) {
+ kkind := k.Kind()
+ if kkind == reflect.Interface {
+ kkind = k.Elem().Kind()
+ }
+ if kkind == reflect.Map || kkind == reflect.Slice {
+ failf("invalid map key: %#v", k.Interface())
+ }
+ e := reflect.New(et).Elem()
+ if d.unmarshal(n.Content[i+1], e) {
+ out.SetMapIndex(k, e)
+ }
+ }
+ }
+ d.stringMapType = stringMapType
+ d.generalMapType = generalMapType
+ return true
+}
+
+func isStringMap(n *Node) bool {
+ if n.Kind != MappingNode {
+ return false
+ }
+ l := len(n.Content)
+ for i := 0; i < l; i += 2 {
+ if n.Content[i].ShortTag() != strTag {
+ return false
+ }
+ }
+ return true
+}
+
+func (d *decoder) mappingStruct(n *Node, out reflect.Value) (good bool) {
+ sinfo, err := getStructInfo(out.Type())
+ if err != nil {
+ panic(err)
+ }
+
+ var inlineMap reflect.Value
+ var elemType reflect.Type
+ if sinfo.InlineMap != -1 {
+ inlineMap = out.Field(sinfo.InlineMap)
+ inlineMap.Set(reflect.New(inlineMap.Type()).Elem())
+ elemType = inlineMap.Type().Elem()
+ }
+
+ for _, index := range sinfo.InlineUnmarshalers {
+ field := d.fieldByIndex(n, out, index)
+ d.prepare(n, field)
+ }
+
+ var doneFields []bool
+ if d.uniqueKeys {
+ doneFields = make([]bool, len(sinfo.FieldsList))
+ }
+ name := settableValueOf("")
+ l := len(n.Content)
+ for i := 0; i < l; i += 2 {
+ ni := n.Content[i]
+ if isMerge(ni) {
+ d.merge(n.Content[i+1], out)
+ continue
+ }
+ if !d.unmarshal(ni, name) {
+ continue
+ }
+ if info, ok := sinfo.FieldsMap[name.String()]; ok {
+ if d.uniqueKeys {
+ if doneFields[info.Id] {
+ d.terrors = append(d.terrors, fmt.Sprintf("line %d: field %s already set in type %s", ni.Line, name.String(), out.Type()))
+ continue
+ }
+ doneFields[info.Id] = true
+ }
+ var field reflect.Value
+ if info.Inline == nil {
+ field = out.Field(info.Num)
+ } else {
+ field = d.fieldByIndex(n, out, info.Inline)
+ }
+ d.unmarshal(n.Content[i+1], field)
+ } else if sinfo.InlineMap != -1 {
+ if inlineMap.IsNil() {
+ inlineMap.Set(reflect.MakeMap(inlineMap.Type()))
+ }
+ value := reflect.New(elemType).Elem()
+ d.unmarshal(n.Content[i+1], value)
+ inlineMap.SetMapIndex(name, value)
+ } else if d.knownFields {
+ d.terrors = append(d.terrors, fmt.Sprintf("line %d: field %s not found in type %s", ni.Line, name.String(), out.Type()))
+ }
+ }
+ return true
+}
+
+func failWantMap() {
+ failf("map merge requires map or sequence of maps as the value")
+}
+
+func (d *decoder) merge(n *Node, out reflect.Value) {
+ switch n.Kind {
+ case MappingNode:
+ d.unmarshal(n, out)
+ case AliasNode:
+ if n.Alias != nil && n.Alias.Kind != MappingNode {
+ failWantMap()
+ }
+ d.unmarshal(n, out)
+ case SequenceNode:
+ // Step backwards as earlier nodes take precedence.
+ for i := len(n.Content) - 1; i >= 0; i-- {
+ ni := n.Content[i]
+ if ni.Kind == AliasNode {
+ if ni.Alias != nil && ni.Alias.Kind != MappingNode {
+ failWantMap()
+ }
+ } else if ni.Kind != MappingNode {
+ failWantMap()
+ }
+ d.unmarshal(ni, out)
+ }
+ default:
+ failWantMap()
+ }
+}
+
+func isMerge(n *Node) bool {
+ return n.Kind == ScalarNode && n.Value == "<<" && (n.Tag == "" || n.Tag == "!" || shortTag(n.Tag) == mergeTag)
+}