/usr/share/gocode/src/github.com/DHowett/go-plist/typeinfo.go is in golang-github-dhowett-go-plist-dev 0.0~git20160708.0.fec78c8-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 | package plist
import (
"reflect"
"strings"
"sync"
)
// typeInfo holds details for the plist representation of a type.
type typeInfo struct {
fields []fieldInfo
}
// fieldInfo holds details for the plist representation of a single field.
type fieldInfo struct {
idx []int
name string
omitEmpty bool
}
var tinfoMap = make(map[reflect.Type]*typeInfo)
var tinfoLock sync.RWMutex
// getTypeInfo returns the typeInfo structure with details necessary
// for marshalling and unmarshalling typ.
func getTypeInfo(typ reflect.Type) (*typeInfo, error) {
tinfoLock.RLock()
tinfo, ok := tinfoMap[typ]
tinfoLock.RUnlock()
if ok {
return tinfo, nil
}
tinfo = &typeInfo{}
if typ.Kind() == reflect.Struct {
n := typ.NumField()
for i := 0; i < n; i++ {
f := typ.Field(i)
if f.PkgPath != "" || f.Tag.Get("plist") == "-" {
continue // Private field
}
// For embedded structs, embed its fields.
if f.Anonymous {
t := f.Type
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
if t.Kind() == reflect.Struct {
inner, err := getTypeInfo(t)
if err != nil {
return nil, err
}
for _, finfo := range inner.fields {
finfo.idx = append([]int{i}, finfo.idx...)
if err := addFieldInfo(typ, tinfo, &finfo); err != nil {
return nil, err
}
}
continue
}
}
finfo, err := structFieldInfo(typ, &f)
if err != nil {
return nil, err
}
// Add the field if it doesn't conflict with other fields.
if err := addFieldInfo(typ, tinfo, finfo); err != nil {
return nil, err
}
}
}
tinfoLock.Lock()
tinfoMap[typ] = tinfo
tinfoLock.Unlock()
return tinfo, nil
}
// structFieldInfo builds and returns a fieldInfo for f.
func structFieldInfo(typ reflect.Type, f *reflect.StructField) (*fieldInfo, error) {
finfo := &fieldInfo{idx: f.Index}
// Split the tag from the xml namespace if necessary.
tag := f.Tag.Get("plist")
// Parse flags.
tokens := strings.Split(tag, ",")
tag = tokens[0]
if len(tokens) > 1 {
tag = tokens[0]
for _, flag := range tokens[1:] {
switch flag {
case "omitempty":
finfo.omitEmpty = true
}
}
}
if tag == "" {
// If the name part of the tag is completely empty,
// use the field name
finfo.name = f.Name
return finfo, nil
}
finfo.name = tag
return finfo, nil
}
// addFieldInfo adds finfo to tinfo.fields if there are no
// conflicts, or if conflicts arise from previous fields that were
// obtained from deeper embedded structures than finfo. In the latter
// case, the conflicting entries are dropped.
// A conflict occurs when the path (parent + name) to a field is
// itself a prefix of another path, or when two paths match exactly.
// It is okay for field paths to share a common, shorter prefix.
func addFieldInfo(typ reflect.Type, tinfo *typeInfo, newf *fieldInfo) error {
var conflicts []int
// First, figure all conflicts. Most working code will have none.
for i := range tinfo.fields {
oldf := &tinfo.fields[i]
if newf.name == oldf.name {
conflicts = append(conflicts, i)
}
}
// Without conflicts, add the new field and return.
if conflicts == nil {
tinfo.fields = append(tinfo.fields, *newf)
return nil
}
// If any conflict is shallower, ignore the new field.
// This matches the Go field resolution on embedding.
for _, i := range conflicts {
if len(tinfo.fields[i].idx) < len(newf.idx) {
return nil
}
}
// Otherwise, the new field is shallower, and thus takes precedence,
// so drop the conflicting fields from tinfo and append the new one.
for c := len(conflicts) - 1; c >= 0; c-- {
i := conflicts[c]
copy(tinfo.fields[i:], tinfo.fields[i+1:])
tinfo.fields = tinfo.fields[:len(tinfo.fields)-1]
}
tinfo.fields = append(tinfo.fields, *newf)
return nil
}
// value returns v's field value corresponding to finfo.
// It's equivalent to v.FieldByIndex(finfo.idx), but initializes
// and dereferences pointers as necessary.
func (finfo *fieldInfo) value(v reflect.Value) reflect.Value {
for i, x := range finfo.idx {
if i > 0 {
t := v.Type()
if t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Struct {
if v.IsNil() {
v.Set(reflect.New(v.Type().Elem()))
}
v = v.Elem()
}
}
v = v.Field(x)
}
return v
}
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