forgejo-federation/vendor/github.com/pingcap/tidb/mysql/hex.go
Thomas Boerger b6a95a8cb3 Integrate public as bindata optionally (#293)
* Dropped unused codekit config

* Integrated dynamic and static bindata for public

* Ignore public bindata

* Add a general generate make task

* Integrated flexible public assets into web command

* Updated vendoring, added all missiong govendor deps

* Made the linter happy with the bindata and dynamic code

* Moved public bindata definition to modules directory

* Ignoring the new bindata path now

* Updated to the new public modules import path

* Updated public bindata command and drop the new prefix
2016-11-30 00:26:36 +08:00

85 lines
2.1 KiB
Go

// Copyright 2015 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
package mysql
import (
"encoding/hex"
"fmt"
"strconv"
"strings"
"github.com/juju/errors"
)
// Hex is for mysql hexadecimal literal type.
type Hex struct {
// Value holds numeric value for hexadecimal literal.
Value int64
}
// String implements fmt.Stringer interface.
func (h Hex) String() string {
s := fmt.Sprintf("%X", h.Value)
if len(s)%2 != 0 {
return "0x0" + s
}
return "0x" + s
}
// ToNumber changes hexadecimal type to float64 for numeric operation.
// MySQL treats hexadecimal literal as double type.
func (h Hex) ToNumber() float64 {
return float64(h.Value)
}
// ToString returns the string representation for hexadecimal literal.
func (h Hex) ToString() string {
s := fmt.Sprintf("%x", h.Value)
if len(s)%2 != 0 {
s = "0" + s
}
// should never error.
b, _ := hex.DecodeString(s)
return string(b)
}
// ParseHex parses hexadecimal literal string.
// The string format can be X'val', x'val' or 0xval.
// val must in (0...9, a...z, A...Z).
func ParseHex(s string) (Hex, error) {
if len(s) == 0 {
return Hex{}, errors.Errorf("invalid empty string for parsing hexadecimal literal")
}
if s[0] == 'x' || s[0] == 'X' {
// format is x'val' or X'val'
s = strings.Trim(s[1:], "'")
if len(s)%2 != 0 {
return Hex{}, errors.Errorf("invalid hexadecimal format, must even numbers, but %d", len(s))
}
s = "0x" + s
} else if !strings.HasPrefix(s, "0x") {
// here means format is not x'val', X'val' or 0xval.
return Hex{}, errors.Errorf("invalid hexadecimal format %s", s)
}
n, err := strconv.ParseInt(s, 0, 64)
if err != nil {
return Hex{}, errors.Trace(err)
}
return Hex{Value: n}, nil
}