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710 lines
17 KiB
Go
710 lines
17 KiB
Go
// Go MySQL Driver - A MySQL-Driver for Go's database/sql package
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//
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// Copyright 2012 The Go-MySQL-Driver Authors. All rights reserved.
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//
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// This Source Code Form is subject to the terms of the Mozilla Public
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// License, v. 2.0. If a copy of the MPL was not distributed with this file,
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// You can obtain one at http://mozilla.org/MPL/2.0/.
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package mysql
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import (
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"crypto/tls"
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"database/sql/driver"
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"encoding/binary"
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"fmt"
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"io"
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"strings"
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"sync"
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"sync/atomic"
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"time"
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)
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// Registry for custom tls.Configs
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var (
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tlsConfigLock sync.RWMutex
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tlsConfigRegistry map[string]*tls.Config
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)
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// RegisterTLSConfig registers a custom tls.Config to be used with sql.Open.
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// Use the key as a value in the DSN where tls=value.
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//
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// Note: The provided tls.Config is exclusively owned by the driver after
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// registering it.
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//
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// rootCertPool := x509.NewCertPool()
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// pem, err := ioutil.ReadFile("/path/ca-cert.pem")
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// if err != nil {
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// log.Fatal(err)
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// }
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// if ok := rootCertPool.AppendCertsFromPEM(pem); !ok {
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// log.Fatal("Failed to append PEM.")
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// }
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// clientCert := make([]tls.Certificate, 0, 1)
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// certs, err := tls.LoadX509KeyPair("/path/client-cert.pem", "/path/client-key.pem")
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// if err != nil {
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// log.Fatal(err)
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// }
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// clientCert = append(clientCert, certs)
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// mysql.RegisterTLSConfig("custom", &tls.Config{
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// RootCAs: rootCertPool,
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// Certificates: clientCert,
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// })
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// db, err := sql.Open("mysql", "user@tcp(localhost:3306)/test?tls=custom")
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//
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func RegisterTLSConfig(key string, config *tls.Config) error {
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if _, isBool := readBool(key); isBool || strings.ToLower(key) == "skip-verify" {
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return fmt.Errorf("key '%s' is reserved", key)
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}
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tlsConfigLock.Lock()
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if tlsConfigRegistry == nil {
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tlsConfigRegistry = make(map[string]*tls.Config)
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}
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tlsConfigRegistry[key] = config
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tlsConfigLock.Unlock()
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return nil
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}
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// DeregisterTLSConfig removes the tls.Config associated with key.
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func DeregisterTLSConfig(key string) {
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tlsConfigLock.Lock()
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if tlsConfigRegistry != nil {
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delete(tlsConfigRegistry, key)
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}
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tlsConfigLock.Unlock()
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}
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func getTLSConfigClone(key string) (config *tls.Config) {
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tlsConfigLock.RLock()
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if v, ok := tlsConfigRegistry[key]; ok {
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config = cloneTLSConfig(v)
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}
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tlsConfigLock.RUnlock()
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return
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}
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// Returns the bool value of the input.
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// The 2nd return value indicates if the input was a valid bool value
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func readBool(input string) (value bool, valid bool) {
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switch input {
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case "1", "true", "TRUE", "True":
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return true, true
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case "0", "false", "FALSE", "False":
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return false, true
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}
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// Not a valid bool value
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return
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}
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/******************************************************************************
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* Time related utils *
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******************************************************************************/
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// NullTime represents a time.Time that may be NULL.
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// NullTime implements the Scanner interface so
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// it can be used as a scan destination:
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//
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// var nt NullTime
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// err := db.QueryRow("SELECT time FROM foo WHERE id=?", id).Scan(&nt)
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// ...
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// if nt.Valid {
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// // use nt.Time
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// } else {
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// // NULL value
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// }
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//
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// This NullTime implementation is not driver-specific
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type NullTime struct {
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Time time.Time
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Valid bool // Valid is true if Time is not NULL
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}
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// Scan implements the Scanner interface.
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// The value type must be time.Time or string / []byte (formatted time-string),
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// otherwise Scan fails.
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func (nt *NullTime) Scan(value interface{}) (err error) {
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if value == nil {
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nt.Time, nt.Valid = time.Time{}, false
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return
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}
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switch v := value.(type) {
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case time.Time:
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nt.Time, nt.Valid = v, true
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return
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case []byte:
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nt.Time, err = parseDateTime(string(v), time.UTC)
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nt.Valid = (err == nil)
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return
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case string:
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nt.Time, err = parseDateTime(v, time.UTC)
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nt.Valid = (err == nil)
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return
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}
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nt.Valid = false
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return fmt.Errorf("Can't convert %T to time.Time", value)
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}
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// Value implements the driver Valuer interface.
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func (nt NullTime) Value() (driver.Value, error) {
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if !nt.Valid {
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return nil, nil
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}
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return nt.Time, nil
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}
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func parseDateTime(str string, loc *time.Location) (t time.Time, err error) {
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base := "0000-00-00 00:00:00.0000000"
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switch len(str) {
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case 10, 19, 21, 22, 23, 24, 25, 26: // up to "YYYY-MM-DD HH:MM:SS.MMMMMM"
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if str == base[:len(str)] {
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return
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}
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t, err = time.Parse(timeFormat[:len(str)], str)
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default:
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err = fmt.Errorf("invalid time string: %s", str)
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return
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}
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// Adjust location
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if err == nil && loc != time.UTC {
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y, mo, d := t.Date()
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h, mi, s := t.Clock()
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t, err = time.Date(y, mo, d, h, mi, s, t.Nanosecond(), loc), nil
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}
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return
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}
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func parseBinaryDateTime(num uint64, data []byte, loc *time.Location) (driver.Value, error) {
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switch num {
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case 0:
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return time.Time{}, nil
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case 4:
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return time.Date(
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int(binary.LittleEndian.Uint16(data[:2])), // year
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time.Month(data[2]), // month
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int(data[3]), // day
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0, 0, 0, 0,
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loc,
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), nil
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case 7:
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return time.Date(
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int(binary.LittleEndian.Uint16(data[:2])), // year
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time.Month(data[2]), // month
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int(data[3]), // day
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int(data[4]), // hour
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int(data[5]), // minutes
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int(data[6]), // seconds
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0,
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loc,
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), nil
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case 11:
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return time.Date(
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int(binary.LittleEndian.Uint16(data[:2])), // year
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time.Month(data[2]), // month
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int(data[3]), // day
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int(data[4]), // hour
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int(data[5]), // minutes
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int(data[6]), // seconds
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int(binary.LittleEndian.Uint32(data[7:11]))*1000, // nanoseconds
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loc,
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), nil
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}
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return nil, fmt.Errorf("invalid DATETIME packet length %d", num)
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}
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// zeroDateTime is used in formatBinaryDateTime to avoid an allocation
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// if the DATE or DATETIME has the zero value.
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// It must never be changed.
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// The current behavior depends on database/sql copying the result.
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var zeroDateTime = []byte("0000-00-00 00:00:00.000000")
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const digits01 = "0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789"
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const digits10 = "0000000000111111111122222222223333333333444444444455555555556666666666777777777788888888889999999999"
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func formatBinaryDateTime(src []byte, length uint8, justTime bool) (driver.Value, error) {
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// length expects the deterministic length of the zero value,
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// negative time and 100+ hours are automatically added if needed
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if len(src) == 0 {
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if justTime {
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return zeroDateTime[11 : 11+length], nil
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}
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return zeroDateTime[:length], nil
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}
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var dst []byte // return value
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var pt, p1, p2, p3 byte // current digit pair
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var zOffs byte // offset of value in zeroDateTime
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if justTime {
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switch length {
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case
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8, // time (can be up to 10 when negative and 100+ hours)
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10, 11, 12, 13, 14, 15: // time with fractional seconds
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default:
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return nil, fmt.Errorf("illegal TIME length %d", length)
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}
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switch len(src) {
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case 8, 12:
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default:
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return nil, fmt.Errorf("invalid TIME packet length %d", len(src))
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}
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// +2 to enable negative time and 100+ hours
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dst = make([]byte, 0, length+2)
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if src[0] == 1 {
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dst = append(dst, '-')
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}
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if src[1] != 0 {
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hour := uint16(src[1])*24 + uint16(src[5])
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pt = byte(hour / 100)
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p1 = byte(hour - 100*uint16(pt))
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dst = append(dst, digits01[pt])
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} else {
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p1 = src[5]
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}
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zOffs = 11
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src = src[6:]
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} else {
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switch length {
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case 10, 19, 21, 22, 23, 24, 25, 26:
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default:
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t := "DATE"
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if length > 10 {
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t += "TIME"
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}
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return nil, fmt.Errorf("illegal %s length %d", t, length)
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}
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switch len(src) {
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case 4, 7, 11:
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default:
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t := "DATE"
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if length > 10 {
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t += "TIME"
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}
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return nil, fmt.Errorf("illegal %s packet length %d", t, len(src))
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}
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dst = make([]byte, 0, length)
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// start with the date
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year := binary.LittleEndian.Uint16(src[:2])
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pt = byte(year / 100)
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p1 = byte(year - 100*uint16(pt))
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p2, p3 = src[2], src[3]
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dst = append(dst,
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digits10[pt], digits01[pt],
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digits10[p1], digits01[p1], '-',
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digits10[p2], digits01[p2], '-',
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digits10[p3], digits01[p3],
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)
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if length == 10 {
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return dst, nil
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}
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if len(src) == 4 {
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return append(dst, zeroDateTime[10:length]...), nil
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}
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dst = append(dst, ' ')
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p1 = src[4] // hour
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src = src[5:]
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}
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// p1 is 2-digit hour, src is after hour
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p2, p3 = src[0], src[1]
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dst = append(dst,
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digits10[p1], digits01[p1], ':',
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digits10[p2], digits01[p2], ':',
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digits10[p3], digits01[p3],
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)
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if length <= byte(len(dst)) {
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return dst, nil
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}
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src = src[2:]
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if len(src) == 0 {
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return append(dst, zeroDateTime[19:zOffs+length]...), nil
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}
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microsecs := binary.LittleEndian.Uint32(src[:4])
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p1 = byte(microsecs / 10000)
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microsecs -= 10000 * uint32(p1)
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p2 = byte(microsecs / 100)
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microsecs -= 100 * uint32(p2)
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p3 = byte(microsecs)
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switch decimals := zOffs + length - 20; decimals {
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default:
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return append(dst, '.',
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digits10[p1], digits01[p1],
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digits10[p2], digits01[p2],
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digits10[p3], digits01[p3],
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), nil
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case 1:
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return append(dst, '.',
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digits10[p1],
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), nil
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case 2:
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return append(dst, '.',
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digits10[p1], digits01[p1],
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), nil
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case 3:
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return append(dst, '.',
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digits10[p1], digits01[p1],
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digits10[p2],
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), nil
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case 4:
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return append(dst, '.',
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digits10[p1], digits01[p1],
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digits10[p2], digits01[p2],
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), nil
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case 5:
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return append(dst, '.',
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digits10[p1], digits01[p1],
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digits10[p2], digits01[p2],
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digits10[p3],
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), nil
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}
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}
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/******************************************************************************
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* Convert from and to bytes *
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******************************************************************************/
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func uint64ToBytes(n uint64) []byte {
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return []byte{
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byte(n),
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byte(n >> 8),
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byte(n >> 16),
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byte(n >> 24),
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byte(n >> 32),
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byte(n >> 40),
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byte(n >> 48),
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byte(n >> 56),
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}
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}
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func uint64ToString(n uint64) []byte {
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var a [20]byte
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i := 20
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// U+0030 = 0
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// ...
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// U+0039 = 9
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var q uint64
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for n >= 10 {
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i--
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q = n / 10
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a[i] = uint8(n-q*10) + 0x30
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n = q
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}
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i--
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a[i] = uint8(n) + 0x30
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return a[i:]
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}
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// treats string value as unsigned integer representation
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func stringToInt(b []byte) int {
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val := 0
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for i := range b {
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val *= 10
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val += int(b[i] - 0x30)
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}
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return val
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}
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// returns the string read as a bytes slice, wheter the value is NULL,
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// the number of bytes read and an error, in case the string is longer than
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// the input slice
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func readLengthEncodedString(b []byte) ([]byte, bool, int, error) {
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// Get length
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num, isNull, n := readLengthEncodedInteger(b)
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if num < 1 {
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return b[n:n], isNull, n, nil
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}
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n += int(num)
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// Check data length
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if len(b) >= n {
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return b[n-int(num) : n : n], false, n, nil
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}
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return nil, false, n, io.EOF
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}
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// returns the number of bytes skipped and an error, in case the string is
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// longer than the input slice
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func skipLengthEncodedString(b []byte) (int, error) {
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// Get length
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num, _, n := readLengthEncodedInteger(b)
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if num < 1 {
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return n, nil
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}
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n += int(num)
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// Check data length
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if len(b) >= n {
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return n, nil
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}
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return n, io.EOF
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}
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// returns the number read, whether the value is NULL and the number of bytes read
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func readLengthEncodedInteger(b []byte) (uint64, bool, int) {
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// See issue #349
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if len(b) == 0 {
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return 0, true, 1
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}
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switch b[0] {
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// 251: NULL
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case 0xfb:
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return 0, true, 1
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// 252: value of following 2
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case 0xfc:
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return uint64(b[1]) | uint64(b[2])<<8, false, 3
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// 253: value of following 3
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case 0xfd:
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return uint64(b[1]) | uint64(b[2])<<8 | uint64(b[3])<<16, false, 4
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// 254: value of following 8
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case 0xfe:
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return uint64(b[1]) | uint64(b[2])<<8 | uint64(b[3])<<16 |
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uint64(b[4])<<24 | uint64(b[5])<<32 | uint64(b[6])<<40 |
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uint64(b[7])<<48 | uint64(b[8])<<56,
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false, 9
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}
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// 0-250: value of first byte
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return uint64(b[0]), false, 1
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}
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// encodes a uint64 value and appends it to the given bytes slice
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func appendLengthEncodedInteger(b []byte, n uint64) []byte {
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switch {
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case n <= 250:
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return append(b, byte(n))
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case n <= 0xffff:
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return append(b, 0xfc, byte(n), byte(n>>8))
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case n <= 0xffffff:
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return append(b, 0xfd, byte(n), byte(n>>8), byte(n>>16))
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}
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return append(b, 0xfe, byte(n), byte(n>>8), byte(n>>16), byte(n>>24),
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byte(n>>32), byte(n>>40), byte(n>>48), byte(n>>56))
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}
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// reserveBuffer checks cap(buf) and expand buffer to len(buf) + appendSize.
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// If cap(buf) is not enough, reallocate new buffer.
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func reserveBuffer(buf []byte, appendSize int) []byte {
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newSize := len(buf) + appendSize
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if cap(buf) < newSize {
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// Grow buffer exponentially
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newBuf := make([]byte, len(buf)*2+appendSize)
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copy(newBuf, buf)
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buf = newBuf
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}
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return buf[:newSize]
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}
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// escapeBytesBackslash escapes []byte with backslashes (\)
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|
// This escapes the contents of a string (provided as []byte) by adding backslashes before special
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// characters, and turning others into specific escape sequences, such as
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// turning newlines into \n and null bytes into \0.
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// https://github.com/mysql/mysql-server/blob/mysql-5.7.5/mysys/charset.c#L823-L932
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func escapeBytesBackslash(buf, v []byte) []byte {
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pos := len(buf)
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buf = reserveBuffer(buf, len(v)*2)
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for _, c := range v {
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switch c {
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case '\x00':
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buf[pos] = '\\'
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buf[pos+1] = '0'
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pos += 2
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case '\n':
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buf[pos] = '\\'
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buf[pos+1] = 'n'
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pos += 2
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case '\r':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = 'r'
|
|
pos += 2
|
|
case '\x1a':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = 'Z'
|
|
pos += 2
|
|
case '\'':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '\''
|
|
pos += 2
|
|
case '"':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '"'
|
|
pos += 2
|
|
case '\\':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '\\'
|
|
pos += 2
|
|
default:
|
|
buf[pos] = c
|
|
pos++
|
|
}
|
|
}
|
|
|
|
return buf[:pos]
|
|
}
|
|
|
|
// escapeStringBackslash is similar to escapeBytesBackslash but for string.
|
|
func escapeStringBackslash(buf []byte, v string) []byte {
|
|
pos := len(buf)
|
|
buf = reserveBuffer(buf, len(v)*2)
|
|
|
|
for i := 0; i < len(v); i++ {
|
|
c := v[i]
|
|
switch c {
|
|
case '\x00':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '0'
|
|
pos += 2
|
|
case '\n':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = 'n'
|
|
pos += 2
|
|
case '\r':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = 'r'
|
|
pos += 2
|
|
case '\x1a':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = 'Z'
|
|
pos += 2
|
|
case '\'':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '\''
|
|
pos += 2
|
|
case '"':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '"'
|
|
pos += 2
|
|
case '\\':
|
|
buf[pos] = '\\'
|
|
buf[pos+1] = '\\'
|
|
pos += 2
|
|
default:
|
|
buf[pos] = c
|
|
pos++
|
|
}
|
|
}
|
|
|
|
return buf[:pos]
|
|
}
|
|
|
|
// escapeBytesQuotes escapes apostrophes in []byte by doubling them up.
|
|
// This escapes the contents of a string by doubling up any apostrophes that
|
|
// it contains. This is used when the NO_BACKSLASH_ESCAPES SQL_MODE is in
|
|
// effect on the server.
|
|
// https://github.com/mysql/mysql-server/blob/mysql-5.7.5/mysys/charset.c#L963-L1038
|
|
func escapeBytesQuotes(buf, v []byte) []byte {
|
|
pos := len(buf)
|
|
buf = reserveBuffer(buf, len(v)*2)
|
|
|
|
for _, c := range v {
|
|
if c == '\'' {
|
|
buf[pos] = '\''
|
|
buf[pos+1] = '\''
|
|
pos += 2
|
|
} else {
|
|
buf[pos] = c
|
|
pos++
|
|
}
|
|
}
|
|
|
|
return buf[:pos]
|
|
}
|
|
|
|
// escapeStringQuotes is similar to escapeBytesQuotes but for string.
|
|
func escapeStringQuotes(buf []byte, v string) []byte {
|
|
pos := len(buf)
|
|
buf = reserveBuffer(buf, len(v)*2)
|
|
|
|
for i := 0; i < len(v); i++ {
|
|
c := v[i]
|
|
if c == '\'' {
|
|
buf[pos] = '\''
|
|
buf[pos+1] = '\''
|
|
pos += 2
|
|
} else {
|
|
buf[pos] = c
|
|
pos++
|
|
}
|
|
}
|
|
|
|
return buf[:pos]
|
|
}
|
|
|
|
/******************************************************************************
|
|
* Sync utils *
|
|
******************************************************************************/
|
|
|
|
// noCopy may be embedded into structs which must not be copied
|
|
// after the first use.
|
|
//
|
|
// See https://github.com/golang/go/issues/8005#issuecomment-190753527
|
|
// for details.
|
|
type noCopy struct{}
|
|
|
|
// Lock is a no-op used by -copylocks checker from `go vet`.
|
|
func (*noCopy) Lock() {}
|
|
|
|
// atomicBool is a wrapper around uint32 for usage as a boolean value with
|
|
// atomic access.
|
|
type atomicBool struct {
|
|
_noCopy noCopy
|
|
value uint32
|
|
}
|
|
|
|
// IsSet returns wether the current boolean value is true
|
|
func (ab *atomicBool) IsSet() bool {
|
|
return atomic.LoadUint32(&ab.value) > 0
|
|
}
|
|
|
|
// Set sets the value of the bool regardless of the previous value
|
|
func (ab *atomicBool) Set(value bool) {
|
|
if value {
|
|
atomic.StoreUint32(&ab.value, 1)
|
|
} else {
|
|
atomic.StoreUint32(&ab.value, 0)
|
|
}
|
|
}
|
|
|
|
// TrySet sets the value of the bool and returns wether the value changed
|
|
func (ab *atomicBool) TrySet(value bool) bool {
|
|
if value {
|
|
return atomic.SwapUint32(&ab.value, 1) == 0
|
|
}
|
|
return atomic.SwapUint32(&ab.value, 0) > 0
|
|
}
|
|
|
|
// atomicError is a wrapper for atomically accessed error values
|
|
type atomicError struct {
|
|
_noCopy noCopy
|
|
value atomic.Value
|
|
}
|
|
|
|
// Set sets the error value regardless of the previous value.
|
|
// The value must not be nil
|
|
func (ae *atomicError) Set(value error) {
|
|
ae.value.Store(value)
|
|
}
|
|
|
|
// Value returns the current error value
|
|
func (ae *atomicError) Value() error {
|
|
if v := ae.value.Load(); v != nil {
|
|
// this will panic if the value doesn't implement the error interface
|
|
return v.(error)
|
|
}
|
|
return nil
|
|
}
|