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path: root/vendor/github.com/BurntSushi/toml/decode.go
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-rw-r--r--vendor/github.com/BurntSushi/toml/decode.go512
1 files changed, 512 insertions, 0 deletions
diff --git a/vendor/github.com/BurntSushi/toml/decode.go b/vendor/github.com/BurntSushi/toml/decode.go
new file mode 100644
index 0000000..98c8aa6
--- /dev/null
+++ b/vendor/github.com/BurntSushi/toml/decode.go
@@ -0,0 +1,512 @@
+package toml
+
+import (
+ "fmt"
+ "io"
+ "io/ioutil"
+ "math"
+ "reflect"
+ "strings"
+ "time"
+)
+
+var e = fmt.Errorf
+
+// Unmarshaler is the interface implemented by objects that can unmarshal a
+// TOML description of themselves.
+type Unmarshaler interface {
+ UnmarshalTOML(interface{}) error
+}
+
+// Unmarshal decodes the contents of `p` in TOML format into a pointer `v`.
+func Unmarshal(p []byte, v interface{}) error {
+ _, err := Decode(string(p), v)
+ return err
+}
+
+// Primitive is a TOML value that hasn't been decoded into a Go value.
+// When using the various `Decode*` functions, the type `Primitive` may
+// be given to any value, and its decoding will be delayed.
+//
+// A `Primitive` value can be decoded using the `PrimitiveDecode` function.
+//
+// The underlying representation of a `Primitive` value is subject to change.
+// Do not rely on it.
+//
+// N.B. Primitive values are still parsed, so using them will only avoid
+// the overhead of reflection. They can be useful when you don't know the
+// exact type of TOML data until run time.
+type Primitive struct {
+ undecoded interface{}
+ context Key
+}
+
+// DEPRECATED!
+//
+// Use MetaData.PrimitiveDecode instead.
+func PrimitiveDecode(primValue Primitive, v interface{}) error {
+ md := MetaData{decoded: make(map[string]bool)}
+ return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// PrimitiveDecode is just like the other `Decode*` functions, except it
+// decodes a TOML value that has already been parsed. Valid primitive values
+// can *only* be obtained from values filled by the decoder functions,
+// including this method. (i.e., `v` may contain more `Primitive`
+// values.)
+//
+// Meta data for primitive values is included in the meta data returned by
+// the `Decode*` functions with one exception: keys returned by the Undecoded
+// method will only reflect keys that were decoded. Namely, any keys hidden
+// behind a Primitive will be considered undecoded. Executing this method will
+// update the undecoded keys in the meta data. (See the example.)
+func (md *MetaData) PrimitiveDecode(primValue Primitive, v interface{}) error {
+ md.context = primValue.context
+ defer func() { md.context = nil }()
+ return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// Decode will decode the contents of `data` in TOML format into a pointer
+// `v`.
+//
+// TOML hashes correspond to Go structs or maps. (Dealer's choice. They can be
+// used interchangeably.)
+//
+// TOML arrays of tables correspond to either a slice of structs or a slice
+// of maps.
+//
+// TOML datetimes correspond to Go `time.Time` values.
+//
+// All other TOML types (float, string, int, bool and array) correspond
+// to the obvious Go types.
+//
+// An exception to the above rules is if a type implements the
+// encoding.TextUnmarshaler interface. In this case, any primitive TOML value
+// (floats, strings, integers, booleans and datetimes) will be converted to
+// a byte string and given to the value's UnmarshalText method. See the
+// Unmarshaler example for a demonstration with time duration strings.
+//
+// Key mapping
+//
+// TOML keys can map to either keys in a Go map or field names in a Go
+// struct. The special `toml` struct tag may be used to map TOML keys to
+// struct fields that don't match the key name exactly. (See the example.)
+// A case insensitive match to struct names will be tried if an exact match
+// can't be found.
+//
+// The mapping between TOML values and Go values is loose. That is, there
+// may exist TOML values that cannot be placed into your representation, and
+// there may be parts of your representation that do not correspond to
+// TOML values. This loose mapping can be made stricter by using the IsDefined
+// and/or Undecoded methods on the MetaData returned.
+//
+// This decoder will not handle cyclic types. If a cyclic type is passed,
+// `Decode` will not terminate.
+func Decode(data string, v interface{}) (MetaData, error) {
+ rv := reflect.ValueOf(v)
+ if rv.Kind() != reflect.Ptr {
+ return MetaData{}, e("Decode of non-pointer type %s", reflect.TypeOf(v))
+ }
+ if rv.IsNil() {
+ return MetaData{}, e("Decode of nil %s", reflect.TypeOf(v))
+ }
+ p, err := parse(data)
+ if err != nil {
+ return MetaData{}, err
+ }
+ md := MetaData{
+ p.mapping, p.types, p.ordered,
+ make(map[string]bool, len(p.ordered)), nil,
+ }
+ return md, md.unify(p.mapping, indirect(rv))
+}
+
+// DecodeFile is just like Decode, except it will automatically read the
+// contents of the file at `fpath` and decode it for you.
+func DecodeFile(fpath string, v interface{}) (MetaData, error) {
+ bs, err := ioutil.ReadFile(fpath)
+ if err != nil {
+ return MetaData{}, err
+ }
+ return Decode(string(bs), v)
+}
+
+// DecodeReader is just like Decode, except it will consume all bytes
+// from the reader and decode it for you.
+func DecodeReader(r io.Reader, v interface{}) (MetaData, error) {
+ bs, err := ioutil.ReadAll(r)
+ if err != nil {
+ return MetaData{}, err
+ }
+ return Decode(string(bs), v)
+}
+
+// unify performs a sort of type unification based on the structure of `rv`,
+// which is the client representation.
+//
+// Any type mismatch produces an error. Finding a type that we don't know
+// how to handle produces an unsupported type error.
+func (md *MetaData) unify(data interface{}, rv reflect.Value) error {
+
+ // Special case. Look for a `Primitive` value.
+ if rv.Type() == reflect.TypeOf((*Primitive)(nil)).Elem() {
+ // Save the undecoded data and the key context into the primitive
+ // value.
+ context := make(Key, len(md.context))
+ copy(context, md.context)
+ rv.Set(reflect.ValueOf(Primitive{
+ undecoded: data,
+ context: context,
+ }))
+ return nil
+ }
+
+ // Special case. Unmarshaler Interface support.
+ if rv.CanAddr() {
+ if v, ok := rv.Addr().Interface().(Unmarshaler); ok {
+ return v.UnmarshalTOML(data)
+ }
+ }
+
+ // Special case. Handle time.Time values specifically.
+ // TODO: Remove this code when we decide to drop support for Go 1.1.
+ // This isn't necessary in Go 1.2 because time.Time satisfies the encoding
+ // interfaces.
+ if rv.Type().AssignableTo(rvalue(time.Time{}).Type()) {
+ return md.unifyDatetime(data, rv)
+ }
+
+ // Special case. Look for a value satisfying the TextUnmarshaler interface.
+ if v, ok := rv.Interface().(TextUnmarshaler); ok {
+ return md.unifyText(data, v)
+ }
+ // BUG(burntsushi)
+ // The behavior here is incorrect whenever a Go type satisfies the
+ // encoding.TextUnmarshaler interface but also corresponds to a TOML
+ // hash or array. In particular, the unmarshaler should only be applied
+ // to primitive TOML values. But at this point, it will be applied to
+ // all kinds of values and produce an incorrect error whenever those values
+ // are hashes or arrays (including arrays of tables).
+
+ k := rv.Kind()
+
+ // laziness
+ if k >= reflect.Int && k <= reflect.Uint64 {
+ return md.unifyInt(data, rv)
+ }
+ switch k {
+ case reflect.Ptr:
+ elem := reflect.New(rv.Type().Elem())
+ err := md.unify(data, reflect.Indirect(elem))
+ if err != nil {
+ return err
+ }
+ rv.Set(elem)
+ return nil
+ case reflect.Struct:
+ return md.unifyStruct(data, rv)
+ case reflect.Map:
+ return md.unifyMap(data, rv)
+ case reflect.Array:
+ return md.unifyArray(data, rv)
+ case reflect.Slice:
+ return md.unifySlice(data, rv)
+ case reflect.String:
+ return md.unifyString(data, rv)
+ case reflect.Bool:
+ return md.unifyBool(data, rv)
+ case reflect.Interface:
+ // we only support empty interfaces.
+ if rv.NumMethod() > 0 {
+ return e("Unsupported type '%s'.", rv.Kind())
+ }
+ return md.unifyAnything(data, rv)
+ case reflect.Float32:
+ fallthrough
+ case reflect.Float64:
+ return md.unifyFloat64(data, rv)
+ }
+ return e("Unsupported type '%s'.", rv.Kind())
+}
+
+func (md *MetaData) unifyStruct(mapping interface{}, rv reflect.Value) error {
+ tmap, ok := mapping.(map[string]interface{})
+ if !ok {
+ if mapping == nil {
+ return nil
+ }
+ return mismatch(rv, "map", mapping)
+ }
+
+ for key, datum := range tmap {
+ var f *field
+ fields := cachedTypeFields(rv.Type())
+ for i := range fields {
+ ff := &fields[i]
+ if ff.name == key {
+ f = ff
+ break
+ }
+ if f == nil && strings.EqualFold(ff.name, key) {
+ f = ff
+ }
+ }
+ if f != nil {
+ subv := rv
+ for _, i := range f.index {
+ subv = indirect(subv.Field(i))
+ }
+ if isUnifiable(subv) {
+ md.decoded[md.context.add(key).String()] = true
+ md.context = append(md.context, key)
+ if err := md.unify(datum, subv); err != nil {
+ return e("Type mismatch for '%s.%s': %s",
+ rv.Type().String(), f.name, err)
+ }
+ md.context = md.context[0 : len(md.context)-1]
+ } else if f.name != "" {
+ // Bad user! No soup for you!
+ return e("Field '%s.%s' is unexported, and therefore cannot "+
+ "be loaded with reflection.", rv.Type().String(), f.name)
+ }
+ }
+ }
+ return nil
+}
+
+func (md *MetaData) unifyMap(mapping interface{}, rv reflect.Value) error {
+ tmap, ok := mapping.(map[string]interface{})
+ if !ok {
+ if tmap == nil {
+ return nil
+ }
+ return badtype("map", mapping)
+ }
+ if rv.IsNil() {
+ rv.Set(reflect.MakeMap(rv.Type()))
+ }
+ for k, v := range tmap {
+ md.decoded[md.context.add(k).String()] = true
+ md.context = append(md.context, k)
+
+ rvkey := indirect(reflect.New(rv.Type().Key()))
+ rvval := reflect.Indirect(reflect.New(rv.Type().Elem()))
+ if err := md.unify(v, rvval); err != nil {
+ return err
+ }
+ md.context = md.context[0 : len(md.context)-1]
+
+ rvkey.SetString(k)
+ rv.SetMapIndex(rvkey, rvval)
+ }
+ return nil
+}
+
+func (md *MetaData) unifyArray(data interface{}, rv reflect.Value) error {
+ datav := reflect.ValueOf(data)
+ if datav.Kind() != reflect.Slice {
+ if !datav.IsValid() {
+ return nil
+ }
+ return badtype("slice", data)
+ }
+ sliceLen := datav.Len()
+ if sliceLen != rv.Len() {
+ return e("expected array length %d; got TOML array of length %d",
+ rv.Len(), sliceLen)
+ }
+ return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySlice(data interface{}, rv reflect.Value) error {
+ datav := reflect.ValueOf(data)
+ if datav.Kind() != reflect.Slice {
+ if !datav.IsValid() {
+ return nil
+ }
+ return badtype("slice", data)
+ }
+ n := datav.Len()
+ if rv.IsNil() || rv.Cap() < n {
+ rv.Set(reflect.MakeSlice(rv.Type(), n, n))
+ }
+ rv.SetLen(n)
+ return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySliceArray(data, rv reflect.Value) error {
+ sliceLen := data.Len()
+ for i := 0; i < sliceLen; i++ {
+ v := data.Index(i).Interface()
+ sliceval := indirect(rv.Index(i))
+ if err := md.unify(v, sliceval); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+func (md *MetaData) unifyDatetime(data interface{}, rv reflect.Value) error {
+ if _, ok := data.(time.Time); ok {
+ rv.Set(reflect.ValueOf(data))
+ return nil
+ }
+ return badtype("time.Time", data)
+}
+
+func (md *MetaData) unifyString(data interface{}, rv reflect.Value) error {
+ if s, ok := data.(string); ok {
+ rv.SetString(s)
+ return nil
+ }
+ return badtype("string", data)
+}
+
+func (md *MetaData) unifyFloat64(data interface{}, rv reflect.Value) error {
+ if num, ok := data.(float64); ok {
+ switch rv.Kind() {
+ case reflect.Float32:
+ fallthrough
+ case reflect.Float64:
+ rv.SetFloat(num)
+ default:
+ panic("bug")
+ }
+ return nil
+ }
+ return badtype("float", data)
+}
+
+func (md *MetaData) unifyInt(data interface{}, rv reflect.Value) error {
+ if num, ok := data.(int64); ok {
+ if rv.Kind() >= reflect.Int && rv.Kind() <= reflect.Int64 {
+ switch rv.Kind() {
+ case reflect.Int, reflect.Int64:
+ // No bounds checking necessary.
+ case reflect.Int8:
+ if num < math.MinInt8 || num > math.MaxInt8 {
+ return e("Value '%d' is out of range for int8.", num)
+ }
+ case reflect.Int16:
+ if num < math.MinInt16 || num > math.MaxInt16 {
+ return e("Value '%d' is out of range for int16.", num)
+ }
+ case reflect.Int32:
+ if num < math.MinInt32 || num > math.MaxInt32 {
+ return e("Value '%d' is out of range for int32.", num)
+ }
+ }
+ rv.SetInt(num)
+ } else if rv.Kind() >= reflect.Uint && rv.Kind() <= reflect.Uint64 {
+ unum := uint64(num)
+ switch rv.Kind() {
+ case reflect.Uint, reflect.Uint64:
+ // No bounds checking necessary.
+ case reflect.Uint8:
+ if num < 0 || unum > math.MaxUint8 {
+ return e("Value '%d' is out of range for uint8.", num)
+ }
+ case reflect.Uint16:
+ if num < 0 || unum > math.MaxUint16 {
+ return e("Value '%d' is out of range for uint16.", num)
+ }
+ case reflect.Uint32:
+ if num < 0 || unum > math.MaxUint32 {
+ return e("Value '%d' is out of range for uint32.", num)
+ }
+ }
+ rv.SetUint(unum)
+ } else {
+ panic("unreachable")
+ }
+ return nil
+ }
+ return badtype("integer", data)
+}
+
+func (md *MetaData) unifyBool(data interface{}, rv reflect.Value) error {
+ if b, ok := data.(bool); ok {
+ rv.SetBool(b)
+ return nil
+ }
+ return badtype("boolean", data)
+}
+
+func (md *MetaData) unifyAnything(data interface{}, rv reflect.Value) error {
+ rv.Set(reflect.ValueOf(data))
+ return nil
+}
+
+func (md *MetaData) unifyText(data interface{}, v TextUnmarshaler) error {
+ var s string
+ switch sdata := data.(type) {
+ case TextMarshaler:
+ text, err := sdata.MarshalText()
+ if err != nil {
+ return err
+ }
+ s = string(text)
+ case fmt.Stringer:
+ s = sdata.String()
+ case string:
+ s = sdata
+ case bool:
+ s = fmt.Sprintf("%v", sdata)
+ case int64:
+ s = fmt.Sprintf("%d", sdata)
+ case float64:
+ s = fmt.Sprintf("%f", sdata)
+ default:
+ return badtype("primitive (string-like)", data)
+ }
+ if err := v.UnmarshalText([]byte(s)); err != nil {
+ return err
+ }
+ return nil
+}
+
+// rvalue returns a reflect.Value of `v`. All pointers are resolved.
+func rvalue(v interface{}) reflect.Value {
+ return indirect(reflect.ValueOf(v))
+}
+
+// indirect returns the value pointed to by a pointer.
+// Pointers are followed until the value is not a pointer.
+// New values are allocated for each nil pointer.
+//
+// An exception to this rule is if the value satisfies an interface of
+// interest to us (like encoding.TextUnmarshaler).
+func indirect(v reflect.Value) reflect.Value {
+ if v.Kind() != reflect.Ptr {
+ if v.CanAddr() {
+ pv := v.Addr()
+ if _, ok := pv.Interface().(TextUnmarshaler); ok {
+ return pv
+ }
+ }
+ return v
+ }
+ if v.IsNil() {
+ v.Set(reflect.New(v.Type().Elem()))
+ }
+ return indirect(reflect.Indirect(v))
+}
+
+func isUnifiable(rv reflect.Value) bool {
+ if rv.CanSet() {
+ return true
+ }
+ if _, ok := rv.Interface().(TextUnmarshaler); ok {
+ return true
+ }
+ return false
+}
+
+func badtype(expected string, data interface{}) error {
+ return e("Expected %s but found '%T'.", expected, data)
+}
+
+func mismatch(user reflect.Value, expected string, data interface{}) error {
+ return e("Type mismatch for %s. Expected %s but found '%T'.",
+ user.Type().String(), expected, data)
+}