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951 lines (858 loc) · 26.5 KB
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Copy pathstruct.go
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951 lines (858 loc) · 26.5 KB
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package ini
import (
"bytes"
"errors"
"fmt"
"reflect"
"slices"
"strconv"
"strings"
"time"
"unicode"
)
// NameMapper represents a ini tag name mapper.
type NameMapper func(string) string
// Built-in name getters.
var (
// SnakeCase converts to format SNAKE_CASE.
SnakeCase NameMapper = func(raw string) string {
newstr := make([]rune, 0, len(raw))
for i, chr := range raw {
if isUpper := 'A' <= chr && chr <= 'Z'; isUpper {
if i > 0 {
newstr = append(newstr, '_')
}
}
newstr = append(newstr, unicode.ToUpper(chr))
}
return string(newstr)
}
// TitleUnderscore converts to format title_underscore.
TitleUnderscore NameMapper = func(raw string) string {
newstr := make([]rune, 0, len(raw))
for i, chr := range raw {
if isUpper := 'A' <= chr && chr <= 'Z'; isUpper {
if i > 0 {
newstr = append(newstr, '_')
}
chr -= 'A' - 'a'
}
newstr = append(newstr, chr)
}
return string(newstr)
}
)
func (s *Section) parseFieldName(raw, actual string) string {
if len(actual) > 0 {
return actual
}
if s.f.options.NameMapper != nil {
return s.f.options.NameMapper(raw)
}
return raw
}
func parseDelim(actual string) string {
if len(actual) > 0 {
return actual
}
return ","
}
// Marshaler is implemented by types that format themselves as a key value.
// ReflectFrom and Marshal call MarshalINI for fields, pointer fields and
// slice elements of such a type, whatever its kind.
type Marshaler interface {
MarshalINI() ([]byte, error)
}
// Unmarshaler is implemented by types that parse themselves from a key value.
// MapTo, StrictMapTo, Unmarshal, List, In and Range call UnmarshalINI with the
// value as Key.String returns it, or with one element of a list. An error
// leaves the field unchanged, and StrictMapTo and StrictList return it.
//
// A struct type that implements Marshaler or Unmarshaler maps to a key, not
// to a section.
type Unmarshaler interface {
UnmarshalINI([]byte) error
}
var (
timeType = reflect.TypeFor[time.Time]()
marshalerType = reflect.TypeFor[Marshaler]()
unmarshalerType = reflect.TypeFor[Unmarshaler]()
)
// isMarshaler and isUnmarshaler report whether t, or a pointer to t,
// implements Marshaler or Unmarshaler.
func isMarshaler(t reflect.Type) bool {
return reflect.PointerTo(t).Implements(marshalerType)
}
func isUnmarshaler(t reflect.Type) bool {
return reflect.PointerTo(t).Implements(unmarshalerType)
}
// isCustomType reports whether t formats or parses itself, so that it maps
// to a key value whatever its kind.
func isCustomType(t reflect.Type) bool {
return isMarshaler(t) || isUnmarshaler(t)
}
// isStructType reports whether t is a struct type that maps to a section,
// which is any struct type but time.Time and custom types.
func isStructType(t reflect.Type) bool {
return t.Kind() == reflect.Struct && t != timeType && !isCustomType(t)
}
// isValueType reports whether a key value can be parsed as or formatted from
// a value of type t.
func isValueType(t reflect.Type) bool {
if t == timeType || isCustomType(t) {
return true
}
switch t.Kind() {
case reflect.String, reflect.Bool,
reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
reflect.Float32, reflect.Float64:
return true
}
return false
}
// isSliceElemType reports whether slices of t are supported.
func isSliceElemType(t reflect.Type) bool {
if t == timeType || isCustomType(t) {
return true
}
switch t.Kind() {
case reflect.String, reflect.Bool, reflect.Int, reflect.Int64, reflect.Uint, reflect.Uint64, reflect.Float64:
return true
}
return false
}
// parseValue parses str as a value of type t, for which isValueType is true.
func parseValue(t reflect.Type, str string) (reflect.Value, error) {
v := reflect.New(t).Elem()
if isUnmarshaler(t) {
err := v.Addr().Interface().(Unmarshaler).UnmarshalINI([]byte(str))
return v, err
}
if t == timeType {
ti, err := time.Parse(time.RFC3339, str)
if err != nil {
return v, err
}
v.Set(reflect.ValueOf(ti))
return v, nil
}
switch t.Kind() {
case reflect.String:
v.SetString(str)
case reflect.Bool:
b, err := parseBool(str)
if err != nil {
return v, err
}
v.SetBool(b)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
i, err := strconv.ParseInt(str, 0, 64)
// A duration can also be given as a number of nanoseconds.
if t.Name() == "Duration" {
if d, derr := time.ParseDuration(str); derr == nil {
i, err = int64(d), nil
}
}
if err != nil {
return v, err
}
if v.OverflowInt(i) {
return v, fmt.Errorf("value %q overflows %s", str, t)
}
v.SetInt(i)
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
u, err := strconv.ParseUint(str, 0, 64)
if err != nil {
return v, err
}
if v.OverflowUint(u) {
return v, fmt.Errorf("value %q overflows %s", str, t)
}
v.SetUint(u)
case reflect.Float32, reflect.Float64:
f, err := strconv.ParseFloat(str, 64)
if err != nil {
return v, err
}
if v.OverflowFloat(f) {
return v, fmt.Errorf("value %q overflows %s", str, t)
}
v.SetFloat(f)
default:
return v, fmt.Errorf("unsupported type %q", t)
}
return v, nil
}
// formatValue does the opposite thing as parseValue.
func formatValue(v reflect.Value) (string, error) {
t := v.Type()
if isMarshaler(t) {
var m Marshaler
switch {
case t.Implements(marshalerType):
m = v.Interface().(Marshaler)
case v.CanAddr():
m = v.Addr().Interface().(Marshaler)
default:
// MarshalINI has a pointer receiver, so call it on a copy.
p := reflect.New(t)
p.Elem().Set(v)
m = p.Interface().(Marshaler)
}
b, err := m.MarshalINI()
return string(b), err
}
if t == timeType {
return v.Interface().(time.Time).Format(time.RFC3339Nano), nil
}
switch v.Kind() {
case reflect.String:
return v.String(), nil
case reflect.Bool:
return fmt.Sprint(v.Bool()), nil
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return fmt.Sprint(v.Int()), nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
return fmt.Sprint(v.Uint()), nil
case reflect.Float32, reflect.Float64:
return fmt.Sprint(v.Float()), nil
}
return "", fmt.Errorf("unsupported type %q", t)
}
// defaultComment sets *c to comment if it is empty, under the file's lock.
func (f *File) defaultComment(c *string, comment string) {
f.maybeLock()
defer f.maybeUnlock()
if *c == "" {
*c = comment
}
}
// tooDeep reports whether path, the struct types being mapped or reflected
// from the outermost one, already holds t twice. Section names are not
// nested, so a recursive struct type would use the same sections forever: it
// is followed one level deep only.
func tooDeep(path []reflect.Type, t reflect.Type) bool {
n := 0
for _, p := range path {
if p == t {
n++
}
}
return n >= 2
}
// decodeSlice sets proper values to slice based on its type.
func decodeSlice(key *Key, field reflect.Value, delim string, allowShadow, isStrict bool) error {
elemType := field.Type().Elem()
if !isSliceElemType(elemType) {
return fmt.Errorf("unsupported type '[]%s'", elemType)
}
var strs []string
if allowShadow {
// As in v1, each value is split at delim with no escapes, and each
// element trimmed and expanded. An empty value, kept with
// PreserveEmptyShadowValues, is an empty element, unless it is the only
// one: an empty slice is written as one empty value.
vals := key.Values()
if len(vals) == 1 && vals[0] == "" {
vals = nil
}
for _, v := range vals {
for _, s := range strings.Split(v, delim) {
strs = append(strs, key.expandValue(strings.TrimSpace(s)))
}
}
} else {
strs = key.Strings(delim)
}
numVals := len(strs)
if numVals == 0 {
return nil
}
slice := reflect.MakeSlice(field.Type(), numVals, numVals)
for i, str := range strs {
val, err := parseValue(elemType, str)
if err != nil {
if isStrict {
return err
}
// An invalid element is left as the zero value.
continue
}
slice.Index(i).Set(val)
}
field.Set(slice)
return nil
}
func wrapStrictError(err error, isStrict bool) error {
if isStrict {
return err
}
return nil
}
// decodeValue sets proper value to field based on its type,
// but it does not return error for failing parsing,
// because we want to use default value that is already assigned to struct.
func decodeValue(t reflect.Type, key *Key, field reflect.Value, delim string, allowShadow, isStrict bool) error {
if t.Kind() == reflect.Slice && !isCustomType(t) {
return decodeSlice(key, field, delim, allowShadow, isStrict)
}
vt := t
isPtr := t.Kind() == reflect.Pointer
if isPtr {
vt = t.Elem()
}
if !isValueType(vt) {
return fmt.Errorf("unsupported type %q", t)
}
str := key.String()
// An empty string keeps the default value of a string field, unless
// the type parses itself.
if vt.Kind() == reflect.String && len(str) == 0 && !isPtr && !isUnmarshaler(vt) {
return nil
}
val, err := parseValue(vt, str)
if err != nil {
return wrapStrictError(err, isStrict)
}
if isPtr {
ptr := reflect.New(vt)
ptr.Elem().Set(val)
val = ptr
}
field.Set(val)
return nil
}
func parseTagOptions(tag string) (rawName string, omitEmpty bool, allowShadow bool, allowNonUnique bool, extends bool) {
opts := strings.SplitN(tag, ",", 5)
rawName = opts[0]
for _, opt := range opts[1:] {
omitEmpty = omitEmpty || (opt == "omitempty")
allowShadow = allowShadow || (opt == "allowshadow")
allowNonUnique = allowNonUnique || (opt == "nonunique")
extends = extends || (opt == "extends")
}
return rawName, omitEmpty, allowShadow, allowNonUnique, extends
}
// decodeStruct maps the given value to the matching field of the given section.
// The sectionIndex is the index (if non unique sections are enabled) to which the value should be added.
// The path holds the struct types being mapped, see tooDeep.
func (s *Section) decodeStruct(val reflect.Value, isStrict bool, sectionIndex int, sectionName string, path []reflect.Type) error {
if val.Kind() == reflect.Pointer {
val = val.Elem()
}
typ := val.Type()
path = append(path, typ)
for i := 0; i < typ.NumField(); i++ {
field := val.Field(i)
tpField := typ.Field(i)
tag := tpField.Tag.Get("ini")
if tag == "-" {
continue
}
rawName, _, allowShadow, allowNonUnique, extends := parseTagOptions(tag)
fieldName := s.parseFieldName(tpField.Name, rawName)
if len(fieldName) == 0 || !field.CanSet() {
continue
}
isStruct := isStructType(tpField.Type)
isStructPtr := tpField.Type.Kind() == reflect.Pointer && isStructType(tpField.Type.Elem())
isAnonymousPtr := isStructPtr && tpField.Anonymous
structType := tpField.Type
if isStructPtr {
structType = tpField.Type.Elem()
}
if isAnonymousPtr && field.IsNil() && !tooDeep(path, structType) {
field.Set(reflect.New(structType))
}
if extends && (isAnonymousPtr || (isStruct && tpField.Anonymous)) {
if tooDeep(path, structType) {
continue
}
fieldSection := s
if rawName != "" {
sectionName = s.name + s.f.options.ChildSectionDelimiter + rawName
if secs, err := s.f.SectionsByName(sectionName); err == nil && sectionIndex < len(secs) {
fieldSection = secs[sectionIndex]
}
}
if err := fieldSection.decodeStruct(field, isStrict, sectionIndex, sectionName, path); err != nil {
return fmt.Errorf("map to field %q: %v", fieldName, err)
}
continue
} else if isStruct || isStructPtr {
if secs, err := s.f.SectionsByName(fieldName); err == nil {
if tooDeep(path, structType) {
continue
}
if len(secs) <= sectionIndex {
return fmt.Errorf("there are not enough sections (%d <= %d) for the field %q", len(secs), sectionIndex, fieldName)
}
// Only set the f
8BD0
ield to non-nil struct value if we have a section for it.
// Otherwise, we end up with a non-nil struct ptr even though there is no data.
if isStructPtr && field.IsNil() {
field.Set(reflect.New(structType))
}
if err = secs[sectionIndex].decodeStruct(field, isStrict, sectionIndex, fieldName, path); err != nil {
return fmt.Errorf("map to field %q: %v", fieldName, err)
}
continue
}
}
// Map non-unique sections
if allowNonUnique && tpField.Type.Kind() == reflect.Slice {
newField, err := s.decodeSections(fieldName, field, isStrict, path)
if err != nil {
return fmt.Errorf("map to slice %q: %v", fieldName, err)
}
field.Set(newField)
continue
}
if key, err := s.GetKey(fieldName); err == nil {
delim := parseDelim(tpField.Tag.Get("delim"))
if err = decodeValue(tpField.Type, key, field, delim, allowShadow, isStrict); err != nil {
return fmt.Errorf("set field %q: %v", fieldName, err)
}
}
}
return nil
}
// decodeSections maps all sections with the same name and returns the new value.
// The type of the Value must be a slice of structs or of pointers to structs.
func (s *Section) decodeSections(secName string, val reflect.Value, isStrict bool, path []reflect.Type) (reflect.Value, error) {
elemType := val.Type().Elem()
isPtr := elemType.Kind() == reflect.Pointer
structType := elemType
if isPtr {
structType = elemType.Elem()
}
if !isStructType(structType) {
return reflect.Value{}, fmt.Errorf("unsupported type %q for non-unique sections", val.Type())
}
secs, err := s.f.SectionsByName(secName)
if err != nil || tooDeep(path, structType) {
// The slice is left as it is when there are no sections.
return val, nil
}
for i, sec := range secs {
elem := reflect.New(structType)
if err = sec.decodeStruct(elem, isStrict, i, sec.name, path); err != nil {
return reflect.Value{}, fmt.Errorf("map to field from section %q: %v", secName, err)
}
if !isPtr {
elem = elem.Elem()
}
val = reflect.Append(val, elem)
}
return val, nil
}
// mapTo maps a section to object v.
func (s *Section) mapTo(v any, isStrict bool) error {
val := reflect.ValueOf(v)
if val.Kind() != reflect.Pointer || val.IsNil() {
return errors.New("not a pointer to a struct")
}
typ := val.Type().Elem()
for typ.Kind() == reflect.Pointer {
typ = typ.Elem()
}
if typ.Kind() != reflect.Struct && typ.Kind() != reflect.Slice {
return errors.New("not a pointer to a struct")
}
// Allocate the nil pointers v points through.
val = val.Elem()
for val.Kind() == reflect.Pointer {
if val.IsNil() {
val.Set(reflect.New(val.Type().Elem()))
}
val = val.Elem()
}
if typ.Kind() == reflect.Slice {
newField, err := s.decodeSections(s.name, val, isStrict, nil)
if err != nil {
return err
}
val.Set(newField)
return nil
}
return s.decodeStruct(val, isStrict, 0, s.name, nil)
}
// MapTo maps section to given struct.
func (s *Section) MapTo(v any) error {
return s.mapTo(v, false)
}
// StrictMapTo maps section to given struct in strict mode,
// which returns all possible error including value parsing error.
func (s *Section) StrictMapTo(v any) error {
return s.mapTo(v, true)
}
// MapTo maps file to given struct.
func (f *File) MapTo(v any) error {
return f.Section("").MapTo(v)
}
// StrictMapTo maps file to given struct in strict mode,
// which returns all possible error including value parsing error.
func (f *File) StrictMapTo(v any) error {
return f.Section("").StrictMapTo(v)
}
// MapTo loads a data source with opts and maps it to the given struct.
// NameMapping sets how field names map to section and key names.
func MapTo(v, source any, opts ...LoadOption) error {
cfg, err := Load(source, opts...)
if err != nil {
return err
}
return cfg.MapTo(v)
}
// StrictMapTo loads a data source with opts and maps it to the given struct
// in strict mode, which returns all possible error including value parsing
// error.
func StrictMapTo(v, source any, opts ...LoadOption) error {
cfg, err := Load(source, opts...)
if err != nil {
return err
}
return cfg.StrictMapTo(v)
}
// encodeSlice does the opposite thing as decodeSlice.
func encodeSlice(key *Key, field reflect.Value, delim string, allowShadow bool) error {
if field.Len() == 0 {
return nil
}
elemType := field.Type().Elem()
if !isSliceElemType(elemType) {
return fmt.Errorf("unsupported type '[]%s'", elemType)
}
vals := make([]string, field.Len())
for i := range vals {
var err error
if vals[i], err = formatValue(field.Index(i)); err != nil {
return err
}
}
if allowShadow {
// Each element is a value of its own, and the reader splits values
// at delim without escapes, as v1 did.
for _, v := range vals {
if strings.Contains(v, delim) {
return fmt.Errorf("element %q contains the delimiter %q, which an allowshadow slice can't hold", v, delim)
}
}
if len(vals) > 1 && !key.s.f.options.AllowShadows {
return errors.New("shadow key is not allowed")
}
// Shadows deduplicated as the file's options say, on a key that
// isn't boolean or auto-increment.
tmp := newKey(key.s, key.name, vals[0])
for _, val := range vals[1:] {
if err := tmp.addShadow(val); err != nil {
return err
}
}
key.s.f.maybeLock()
key.value, key.shadows = tmp.value, tmp.shadows
key.s.f.maybeUnlock()
return nil
}
for i := range vals {
vals[i] = escapeSliceElem(vals[i], delim)
}
key.SetValue(strings.Join(vals, delim))
return nil
}
// escapeSliceElem escapes s so that Key.Strings reads it back as one element
// even when it contains delim. Key.Strings keeps a backslash unless it comes
// before another backslash, delim or the end, so only those are doubled and
// paths like C:\dir are written as they are.
func escapeSliceElem(s, delim string) string {
if !strings.Contains(s, `\`) && !strings.Contains(s, delim) {
return s
}
var b strings.Builder
for i := 0; i < len(s); i++ {
rest := s[i:]
switch {
case strings.HasPrefix(rest, delim):
b.WriteString(`\` + delim)
i += len(delim) - 1
case s[i] == '\\' && (i+1 == len(s) || s[i+1] == '\\' || strings.HasPrefix(s[i+1:], delim)):
b.WriteString(`\\`)
default:
b.WriteByte(s[i])
}
}
return b.String()
}
// encodeValue does the opposite thing as decodeValue.
func encodeValue(t reflect.Type, key *Key, field reflect.Value, delim string, allowShadow bool) error {
switch {
case t.Kind() == reflect.Slice && !isCustomType(t):
return encodeSlice(key, field, delim, allowShadow)
case t.Kind() == reflect.Pointer:
if !field.IsNil() {
return encodeValue(t.Elem(), key, field.Elem(), delim, allowShadow)
}
case isValueType(t):
v, err := formatValue(field)
if err != nil {
return err
}
key.SetValue(v)
default:
return fmt.Errorf("unsupported type %q", t)
}
return nil
}
// CR: copied from encoding/json/encode.go with modifications of time.Time support.
// TODO: add more test coverage.
func isEmptyValue(v reflect.Value) bool {
if v.Type() == timeType {
return v.Interface().(time.Time).IsZero()
}
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.Pointer:
return v.IsNil()
}
return false
}
// StructReflector is the interface implemented by struct types that can extract themselves into INI objects.
type StructReflector interface {
ReflectINIStruct(*File) error
}
// encodeStruct reflects the section from val. The path holds the struct types
// being reflected from, see tooDeep.
func (s *Section) encodeStruct(val reflect.Value, path []reflect.Type) error {
if val.Kind() == reflect.Pointer {
val = val.Elem()
}
typ := val.Type()
path = append(path, typ)
for i := 0; i < typ.NumField(); i++ {
if !val.Field(i).CanInterface() {
continue
}
field := val.Field(i)
tpField := typ.Field(i)
tag := tpField.Tag.Get("ini")
if tag == "-" {
continue
}
rawName, omitEmpty, allowShadow, allowNonUnique, extends := parseTagOptions(tag)
if omitEmpty && isEmptyValue(field) {
continue
}
if r, ok := field.Interface().(StructReflector); ok {
if err := r.ReflectINIStruct(s.f); err != nil {
return err
}
continue
}
fieldName := s.parseFieldName(tpField.Name, rawName)
if len(fieldName) == 0 || !field.CanSet() {
continue
}
// A nil pointer has nothing to write.
if field.Kind() == reflect.Pointer && field.IsNil() {
continue
}
isStruct := isStructType(tpField.Type)
isStructPtr := tpField.Type.Kind() == reflect.Pointer && isStructType(tpField.Type.Elem())
structType := tpField.Type
if isStructPtr {
structType = tpField.Type.Elem()
}
if extends && tpField.Anonymous && (isStruct || isStructPtr) {
if tooDeep(path, structType) {
continue
}
if err := s.encodeStruct(field, path); err != nil {
return fmt.Errorf("reflect from field %q: %v", fieldName, err)
}
continue
}
if isStruct || isStructPtr {
if tooDeep(path, structType) {
continue
}
// Note: The only error here is section doesn't exist.
sec, err := s.f.GetSection(fieldName)
if err != nil {
// Note: fieldName can never be empty here, ignore error.
sec, _ = s.f.NewSection(fieldName)
}
// Add comment from comment tag
s.f.defaultComment(&sec.comment, tpField.Tag.Get("comment"))
if err = sec.encodeStruct(field, path); err != nil {
return fmt.Errorf("reflect from field %q: %v", fieldName, err)
}
continue
}
if allowNonUnique && tpField.Type.Kind() == reflect.Slice {
if field.Len() == 0 {
continue
}
structType = tpField.Type.Elem()
if structType.Kind() == reflect.Pointer {
structType = structType.Elem()
}
if !isStructType(structType) {
return fmt.Errorf("field %q is not a slice of pointer or struct", fieldName)
}
if tooDeep(path, structType) {
continue
}
for i := 0; i < field.Len(); i++ {
elem := field.Index(i)
if elem.Kind() == reflect.Pointer && elem.IsNil() {
continue
}
sec, err := s.f.NewSection(fieldName)
if err != nil {
return err
}
// Add comment from comment tag
s.f.defaultComment(&sec.comment, tpField.Tag.Get("comment"))
if err := sec.encodeStruct(elem, path); err != nil {
return fmt.Errorf("reflect from field %q: %v", fieldName, err)
}
}
continue
}
// Note: Same reason as section.
key, err := s.GetKey(fieldName)
if err != nil {
key, _ = s.NewKey(fieldName, "")
}
// Add comment from comment tag
s.f.defaultComment(&key.comment, tpField.Tag.Get("comment"))
delim := parseDelim(tpField.Tag.Get("delim"))
if err = encodeValue(tpField.Type, key, field, delim, allowShadow); err != nil {
return fmt.Errorf("reflect field %q: %v", fieldName, err)
}
}
return nil
}
// ReflectFrom reflects section from given struct. It overwrites existing ones.
func (s *Section) ReflectFrom(v any) error {
typ := reflect.TypeOf(v)
val := reflect.ValueOf(v)
if typ == nil || (typ.Kind() == reflect.Pointer && val.IsNil()) {
return errors.New("not a pointer to a struct")
}
// A pointer to a pointer to a struct is accepted too, as in
// ReflectFrom(&cfg) with cfg a *Config.
for typ.Kind() == reflect.Pointer && typ.Elem().Kind() == reflect.Pointer {
if val = val.Elem(); val.IsNil() {
return errors.New("not a pointer to a struct")
}
typ = typ.Elem()
}
if !s.f.isDefaultSection(s.name) && s.f.options.AllowNonUniqueSections &&
(typ.Kind() == reflect.Slice || typ.Kind() == reflect.Pointer) {
if typ.Kind() == reflect.Pointer && !isStructType(typ.Elem()) {
return errors.New("not a pointer to a struct")
}
if typ.Kind() == reflect.Slice && (typ.Elem().Kind() != reflect.Pointer || !isStructType(typ.Elem().Elem())) {
return errors.New("not a slice of pointers to structs")
}
// Clear sections to make sure none exists before adding the new ones
s.f.DeleteSection(s.name)
if typ.Kind() == reflect.Pointer {
sec, err := s.f.NewSection(s.name)
if err != nil {
return err
}
return sec.encodeStruct(val.Elem(), nil)
}
for i := 0; i < val.Len(); i++ {
elem := val.Index(i)
if elem.IsNil() {
continue
}
sec, err := s.f.NewSection(s.name)
if err != nil {
return err
}
err = sec.encodeStruct(elem, nil)
if err != nil {
return fmt.Errorf("reflect from %dth field: %v", i, err)
}
}
return nil
}
if typ.Kind() != reflect.Pointer || typ.Elem().Kind() != reflect.Struct {
return errors.New("not a pointer to a struct")
}
return s.encodeStruct(val.Elem(), nil)
}
// ReflectFrom reflects file from given struct.
func (f *File) ReflectFrom(v any) error {
return f.Section("").ReflectFrom(v)
}
// Unmarshal parses INI data with opts and maps it to the struct v points to,
// as File.MapTo does. It reads what Marshal writes: when v has allowshadow
// fields it loads with AllowShadows, AllowDuplicateShadowValues and
// PreserveEmptyShadowValues, and when it has nonunique fields with
// AllowNonUniqueSections, as those tags need. These come after opts, so
// passing one of them as false doesn't drop the values the tags read.
func Unmarshal(data []byte, v any, opts ...LoadOption) error {
if v != nil {
shadows, nonUnique := tagOptions(reflect.TypeOf(v), map[reflect.Type]bool{})
opts = slices.Clone(opts)
if shadows {
opts = append(opts, AllowShadows(true), AllowDuplicateShadowValues(true), PreserveEmptyShadowValues(true))
}
if nonUnique {
opts = append(opts, AllowNonUniqueSections(true))
}
}
return MapTo(v, data, opts...)
}
// tagOptions reports whether t, or a struct type it holds, has allowshadow
// or nonunique fields.
func tagOptions(t reflect.Type, seen map[reflect.Type]bool) (shadows, nonUnique bool) {
for t.Kind() == reflect.Pointer || t.Kind() == reflect.Slice {
t = t.Elem()
}
if !isStructType(t) || seen[t] {
return false, false
}
seen[t] = true
for i := 0; i < t.NumField(); i++ {
_, _, allowShadow, allowNonUnique, _ := parseTagOptions(t.Field(i).Tag.Get("ini"))
s, n := tagOptions(t.Field(i).Type, seen)
shadows = shadows || allowShadow || s
nonUnique = nonUnique || allowNonUnique || n
}
return shadows, nonUnique
}
// Marshal returns the INI encoding of v, a struct or a pointer to one, as
// File.ReflectFrom and File.Write produce it.
func Marshal(v any, opts ...WriteOption) ([]byte, error) {
if val := reflect.ValueOf(v); val.Kind() == reflect.Struct {
ptr := reflect.New(val.Type())
ptr.Elem().Set(val)
v = ptr.Interface()
}
// Shadows and non-unique sections let allowshadow and nonunique fields
// write all their values.
f := Empty(AllowShadows(true), AllowDuplicateShadowValues(true), AllowNonUniqueSections(true))
if err := f.ReflectFrom(v); err != nil {
return nil, err
}
var buf bytes.Buffer
if _, err := f.Write(&buf, opts...); err != nil {
return nil, err
}
return buf.Bytes(), nil
}