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-rw-r--r--vendor/github.com/BurntSushi/toml/decode.go511
1 files changed, 511 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..d3d3b83
--- /dev/null
+++ b/vendor/github.com/BurntSushi/toml/decode.go
@@ -0,0 +1,511 @@
+package toml
+
+import (
+ "encoding"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "math"
+ "os"
+ "reflect"
+ "strings"
+ "time"
+)
+
+// 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.
+//
+// This type can be used for any value, which will cause decoding to be delayed.
+// You can use the PrimitiveDecode() function to "manually" decode these values.
+//
+// NOTE: The underlying representation of a `Primitive` value is subject to
+// change. Do not rely on it.
+//
+// NOTE: 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 runtime.
+type Primitive struct {
+ undecoded interface{}
+ context Key
+}
+
+// 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))
+}
+
+// Decoder decodes TOML data.
+//
+// TOML tables correspond to Go structs or maps (dealer's choice – they can be
+// used interchangeably).
+//
+// TOML table arrays correspond to either a slice of structs or a slice of maps.
+//
+// TOML datetimes correspond to Go time.Time values. Local datetimes are parsed
+// in the local timezone.
+//
+// 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 TextUnmarshaler
+// interface, in which case any primitive TOML value (floats, strings, integers,
+// booleans, datetimes) will be converted to a []byte 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 can 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 does not handle cyclic types. Decode will not terminate if a
+// cyclic type is passed.
+type Decoder struct {
+ r io.Reader
+}
+
+// NewDecoder creates a new Decoder.
+func NewDecoder(r io.Reader) *Decoder {
+ return &Decoder{r: r}
+}
+
+// Decode TOML data in to the pointer `v`.
+func (dec *Decoder) Decode(v interface{}) (MetaData, error) {
+ rv := reflect.ValueOf(v)
+ if rv.Kind() != reflect.Ptr {
+ return MetaData{}, e("Decode of non-pointer %s", reflect.TypeOf(v))
+ }
+ if rv.IsNil() {
+ return MetaData{}, e("Decode of nil %s", reflect.TypeOf(v))
+ }
+
+ // TODO: have parser should read from io.Reader? Or at the very least, make
+ // it read from []byte rather than string
+ data, err := ioutil.ReadAll(dec.r)
+ if err != nil {
+ return MetaData{}, err
+ }
+
+ p, err := parse(string(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))
+}
+
+// Decode the TOML data in to the pointer v.
+//
+// See the documentation on Decoder for a description of the decoding process.
+func Decode(data string, v interface{}) (MetaData, error) {
+ return NewDecoder(strings.NewReader(data)).Decode(v)
+}
+
+// DecodeFile is just like Decode, except it will automatically read the
+// contents of the file at path and decode it for you.
+func DecodeFile(path string, v interface{}) (MetaData, error) {
+ fp, err := os.Open(path)
+ if err != nil {
+ return MetaData{}, err
+ }
+ defer fp.Close()
+ return NewDecoder(fp).Decode(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.
+ // TODO: #76 would make this superfluous after implemented.
+ 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. Look for a value satisfying the TextUnmarshaler interface.
+ if v, ok := rv.Interface().(encoding.TextUnmarshaler); ok {
+ return md.unifyText(data, v)
+ }
+ // TODO:
+ // 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.Type())
+ }
+ 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 e("type mismatch for %s: expected table but found %T",
+ rv.Type().String(), 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 err
+ }
+ md.context = md.context[0 : len(md.context)-1]
+ } else if f.name != "" {
+ // Bad user! No soup for you!
+ return e("cannot write unexported field %s.%s",
+ rv.Type().String(), f.name)
+ }
+ }
+ }
+ return nil
+}
+
+func (md *MetaData) unifyMap(mapping interface{}, rv reflect.Value) error {
+ if k := rv.Type().Key().Kind(); k != reflect.String {
+ return fmt.Errorf(
+ "toml: cannot decode to a map with non-string key type (%s in %q)",
+ k, rv.Type())
+ }
+
+ 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)
+ }
+ if l := datav.Len(); l != rv.Len() {
+ return e("expected array length %d; got TOML array of length %d", rv.Len(), l)
+ }
+ 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 {
+ l := data.Len()
+ for i := 0; i < l; i++ {
+ err := md.unify(data.Index(i).Interface(), indirect(rv.Index(i)))
+ if 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 encoding.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.CanSet() {
+ pv := v.Addr()
+ if _, ok := pv.Interface().(encoding.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().(encoding.TextUnmarshaler); ok {
+ return true
+ }
+ return false
+}
+
+func e(format string, args ...interface{}) error {
+ return fmt.Errorf("toml: "+format, args...)
+}
+
+func badtype(expected string, data interface{}) error {
+ return e("cannot load TOML value of type %T into a Go %s", data, expected)
+}