forked from mirror/go-json
54 lines
1.1 KiB
Go
54 lines
1.1 KiB
Go
package json
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import (
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"errors"
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"strconv"
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"unsafe"
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)
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type floatDecoder struct {
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op func(uintptr, float64)
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}
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func newFloatDecoder(op func(uintptr, float64)) *floatDecoder {
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return &floatDecoder{op: op}
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}
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func (d *floatDecoder) decodeByte(buf []byte, cursor int) ([]byte, int, error) {
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buflen := len(buf)
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for ; cursor < buflen; cursor++ {
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switch buf[cursor] {
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case ' ', '\n', '\t', '\r':
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continue
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case '-', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
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start := cursor
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cursor++
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for ; cursor < buflen; cursor++ {
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tk := int(buf[cursor])
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if (int('0') <= tk && tk <= int('9')) || tk == '.' || tk == 'e' || tk == 'E' {
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continue
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}
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break
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}
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num := buf[start:cursor]
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return num, cursor, nil
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}
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}
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return nil, 0, errors.New("unexpected error number")
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}
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func (d *floatDecoder) decode(buf []byte, cursor int, p uintptr) (int, error) {
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bytes, c, err := d.decodeByte(buf, cursor)
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if err != nil {
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return 0, err
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}
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cursor = c
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s := *(*string)(unsafe.Pointer(&bytes))
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f64, err := strconv.ParseFloat(s, 64)
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if err != nil {
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return 0, err
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}
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d.op(p, f64)
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return cursor, nil
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}
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