diff options
Diffstat (limited to 'libgo/go/encoding/json/decode.go')
| -rw-r--r-- | libgo/go/encoding/json/decode.go | 90 |
1 files changed, 82 insertions, 8 deletions
diff --git a/libgo/go/encoding/json/decode.go b/libgo/go/encoding/json/decode.go index 530e8521dc5..539d952ad68 100644 --- a/libgo/go/encoding/json/decode.go +++ b/libgo/go/encoding/json/decode.go @@ -37,6 +37,7 @@ import ( // To unmarshal JSON into a struct, Unmarshal matches incoming object // keys to the keys used by Marshal (either the struct field name or its tag), // preferring an exact match but also accepting a case-insensitive match. +// Unmarshal will only set exported fields of the struct. // // To unmarshal JSON into an interface value, // Unmarshal stores one of these in the interface value: @@ -48,16 +49,26 @@ import ( // map[string]interface{}, for JSON objects // nil for JSON null // -// To unmarshal a JSON array into a slice, Unmarshal resets the slice to nil -// and then appends each element to the slice. +// To unmarshal a JSON array into a slice, Unmarshal resets the slice length +// to zero and then appends each element to the slice. +// As a special case, to unmarshal an empty JSON array into a slice, +// Unmarshal replaces the slice with a new empty slice. // -// To unmarshal a JSON object into a map, Unmarshal replaces the map -// with an empty map and then adds key-value pairs from the object to -// the map. +// To unmarshal a JSON array into a Go array, Unmarshal decodes +// JSON array elements into corresponding Go array elements. +// If the Go array is smaller than the JSON array, +// the additional JSON array elements are discarded. +// If the JSON array is smaller than the Go array, +// the additional Go array elements are set to zero values. +// +// To unmarshal a JSON object into a string-keyed map, Unmarshal first +// establishes a map to use, If the map is nil, Unmarshal allocates a new map. +// Otherwise Unmarshal reuses the existing map, keeping existing entries. +// Unmarshal then stores key-value pairs from the JSON object into the map. // // If a JSON value is not appropriate for a given target type, // or if a JSON number overflows the target type, Unmarshal -// skips that field and completes the unmarshalling as best it can. +// skips that field and completes the unmarshaling as best it can. // If no more serious errors are encountered, Unmarshal returns // an UnmarshalTypeError describing the earliest such error. // @@ -174,6 +185,66 @@ func (n Number) Int64() (int64, error) { return strconv.ParseInt(string(n), 10, 64) } +// isValidNumber reports whether s is a valid JSON number literal. +func isValidNumber(s string) bool { + // This function implements the JSON numbers grammar. + // See https://tools.ietf.org/html/rfc7159#section-6 + // and http://json.org/number.gif + + if s == "" { + return false + } + + // Optional - + if s[0] == '-' { + s = s[1:] + if s == "" { + return false + } + } + + // Digits + switch { + default: + return false + + case s[0] == '0': + s = s[1:] + + case '1' <= s[0] && s[0] <= '9': + s = s[1:] + for len(s) > 0 && '0' <= s[0] && s[0] <= '9' { + s = s[1:] + } + } + + // . followed by 1 or more digits. + if len(s) >= 2 && s[0] == '.' && '0' <= s[1] && s[1] <= '9' { + s = s[2:] + for len(s) > 0 && '0' <= s[0] && s[0] <= '9' { + s = s[1:] + } + } + + // e or E followed by an optional - or + and + // 1 or more digits. + if len(s) >= 2 && (s[0] == 'e' || s[0] == 'E') { + s = s[1:] + if s[0] == '+' || s[0] == '-' { + s = s[1:] + if s == "" { + return false + } + } + for len(s) > 0 && '0' <= s[0] && s[0] <= '9' { + s = s[1:] + } + } + + // Make sure we are at the end. + return s == "" +} + // decodeState represents the state while decoding a JSON value. type decodeState struct { data []byte @@ -241,7 +312,7 @@ func (d *decodeState) scanWhile(op int) int { newOp = d.scan.eof() d.off = len(d.data) + 1 // mark processed EOF with len+1 } else { - c := int(d.data[d.off]) + c := d.data[d.off] d.off++ newOp = d.scan.step(&d.scan, c) } @@ -757,7 +828,7 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool d.saveError(err) break } - v.Set(reflect.ValueOf(b[0:n])) + v.SetBytes(b[:n]) case reflect.String: v.SetString(string(s)) case reflect.Interface: @@ -781,6 +852,9 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool default: if v.Kind() == reflect.String && v.Type() == numberType { v.SetString(s) + if !isValidNumber(s) { + d.error(fmt.Errorf("json: invalid number literal, trying to unmarshal %q into Number", item)) + } break } if fromQuoted { |