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bee/vendor/github.com/go-sql-driver/mysql/utils.go
2016-12-05 23:07:45 +08:00

976 lines
23 KiB
Go

// Go MySQL Driver - A MySQL-Driver for Go's database/sql package
//
// Copyright 2012 The Go-MySQL-Driver Authors. All rights reserved.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at http://mozilla.org/MPL/2.0/.
package mysql
import (
"crypto/sha1"
"crypto/tls"
"database/sql/driver"
"encoding/binary"
"errors"
"fmt"
"io"
"net"
"net/url"
"strings"
"time"
)
var (
tlsConfigRegister map[string]*tls.Config // Register for custom tls.Configs
errInvalidDSNUnescaped = errors.New("Invalid DSN: Did you forget to escape a param value?")
errInvalidDSNAddr = errors.New("Invalid DSN: Network Address not terminated (missing closing brace)")
errInvalidDSNNoSlash = errors.New("Invalid DSN: Missing the slash separating the database name")
errInvalidDSNUnsafeCollation = errors.New("Invalid DSN: interpolateParams can be used with ascii, latin1, utf8 and utf8mb4 charset")
)
func init() {
tlsConfigRegister = make(map[string]*tls.Config)
}
// RegisterTLSConfig registers a custom tls.Config to be used with sql.Open.
// Use the key as a value in the DSN where tls=value.
//
// rootCertPool := x509.NewCertPool()
// pem, err := ioutil.ReadFile("/path/ca-cert.pem")
// if err != nil {
// log.Fatal(err)
// }
// if ok := rootCertPool.AppendCertsFromPEM(pem); !ok {
// log.Fatal("Failed to append PEM.")
// }
// clientCert := make([]tls.Certificate, 0, 1)
// certs, err := tls.LoadX509KeyPair("/path/client-cert.pem", "/path/client-key.pem")
// if err != nil {
// log.Fatal(err)
// }
// clientCert = append(clientCert, certs)
// mysql.RegisterTLSConfig("custom", &tls.Config{
// RootCAs: rootCertPool,
// Certificates: clientCert,
// })
// db, err := sql.Open("mysql", "user@tcp(localhost:3306)/test?tls=custom")
//
func RegisterTLSConfig(key string, config *tls.Config) error {
if _, isBool := readBool(key); isBool || strings.ToLower(key) == "skip-verify" {
return fmt.Errorf("Key '%s' is reserved", key)
}
tlsConfigRegister[key] = config
return nil
}
// DeregisterTLSConfig removes the tls.Config associated with key.
func DeregisterTLSConfig(key string) {
delete(tlsConfigRegister, key)
}
// parseDSN parses the DSN string to a config
func parseDSN(dsn string) (cfg *config, err error) {
// New config with some default values
cfg = &config{
loc: time.UTC,
collation: defaultCollation,
}
// [user[:password]@][net[(addr)]]/dbname[?param1=value1&paramN=valueN]
// Find the last '/' (since the password or the net addr might contain a '/')
foundSlash := false
for i := len(dsn) - 1; i >= 0; i-- {
if dsn[i] == '/' {
foundSlash = true
var j, k int
// left part is empty if i <= 0
if i > 0 {
// [username[:password]@][protocol[(address)]]
// Find the last '@' in dsn[:i]
for j = i; j >= 0; j-- {
if dsn[j] == '@' {
// username[:password]
// Find the first ':' in dsn[:j]
for k = 0; k < j; k++ {
if dsn[k] == ':' {
cfg.passwd = dsn[k+1 : j]
break
}
}
cfg.user = dsn[:k]
break
}
}
// [protocol[(address)]]
// Find the first '(' in dsn[j+1:i]
for k = j + 1; k < i; k++ {
if dsn[k] == '(' {
// dsn[i-1] must be == ')' if an address is specified
if dsn[i-1] != ')' {
if strings.ContainsRune(dsn[k+1:i], ')') {
return nil, errInvalidDSNUnescaped
}
return nil, errInvalidDSNAddr
}
cfg.addr = dsn[k+1 : i-1]
break
}
}
cfg.net = dsn[j+1 : k]
}
// dbname[?param1=value1&...&paramN=valueN]
// Find the first '?' in dsn[i+1:]
for j = i + 1; j < len(dsn); j++ {
if dsn[j] == '?' {
if err = parseDSNParams(cfg, dsn[j+1:]); err != nil {
return
}
break
}
}
cfg.dbname = dsn[i+1 : j]
break
}
}
if !foundSlash && len(dsn) > 0 {
return nil, errInvalidDSNNoSlash
}
if cfg.interpolateParams && unsafeCollations[cfg.collation] {
return nil, errInvalidDSNUnsafeCollation
}
// Set default network if empty
if cfg.net == "" {
cfg.net = "tcp"
}
// Set default address if empty
if cfg.addr == "" {
switch cfg.net {
case "tcp":
cfg.addr = "127.0.0.1:3306"
case "unix":
cfg.addr = "/tmp/mysql.sock"
default:
return nil, errors.New("Default addr for network '" + cfg.net + "' unknown")
}
}
return
}
// parseDSNParams parses the DSN "query string"
// Values must be url.QueryEscape'ed
func parseDSNParams(cfg *config, params string) (err error) {
for _, v := range strings.Split(params, "&") {
param := strings.SplitN(v, "=", 2)
if len(param) != 2 {
continue
}
// cfg params
switch value := param[1]; param[0] {
// Enable client side placeholder substitution
case "interpolateParams":
var isBool bool
cfg.interpolateParams, isBool = readBool(value)
if !isBool {
return fmt.Errorf("Invalid Bool value: %s", value)
}
// Disable INFILE whitelist / enable all files
case "allowAllFiles":
var isBool bool
cfg.allowAllFiles, isBool = readBool(value)
if !isBool {
return fmt.Errorf("Invalid Bool value: %s", value)
}
// Use cleartext authentication mode (MySQL 5.5.10+)
case "allowCleartextPasswords":
var isBool bool
cfg.allowCleartextPasswords, isBool = readBool(value)
if !isBool {
return fmt.Errorf("Invalid Bool value: %s", value)
}
// Use old authentication mode (pre MySQL 4.1)
case "allowOldPasswords":
var isBool bool
cfg.allowOldPasswords, isBool = readBool(value)
if !isBool {
return fmt.Errorf("Invalid Bool value: %s", value)
}
// Switch "rowsAffected" mode
case "clientFoundRows":
var isBool bool
cfg.clientFoundRows, isBool = readBool(value)
if !isBool {
return fmt.Errorf("Invalid Bool value: %s", value)
}
// Collation
case "collation":
collation, ok := collations[value]
if !ok {
// Note possibility for false negatives:
// could be triggered although the collation is valid if the
// collations map does not contain entries the server supports.
err = errors.New("unknown collation")
return
}
cfg.collation = collation
break
case "columnsWithAlias":
var isBool bool
cfg.columnsWithAlias, isBool = readBool(value)
if !isBool {
return fmt.Errorf("Invalid Bool value: %s", value)
}
// Time Location
case "loc":
if value, err = url.QueryUnescape(value); err != nil {
return
}
cfg.loc, err = time.LoadLocation(value)
if err != nil {
return
}
// Dial Timeout
case "timeout":
cfg.timeout, err = time.ParseDuration(value)
if err != nil {
return
}
// TLS-Encryption
case "tls":
boolValue, isBool := readBool(value)
if isBool {
if boolValue {
cfg.tls = &tls.Config{}
}
} else if value, err := url.QueryUnescape(value); err != nil {
return fmt.Errorf("Invalid value for tls config name: %v", err)
} else {
if strings.ToLower(value) == "skip-verify" {
cfg.tls = &tls.Config{InsecureSkipVerify: true}
} else if tlsConfig, ok := tlsConfigRegister[value]; ok {
if len(tlsConfig.ServerName) == 0 && !tlsConfig.InsecureSkipVerify {
host, _, err := net.SplitHostPort(cfg.addr)
if err == nil {
tlsConfig.ServerName = host
}
}
cfg.tls = tlsConfig
} else {
return fmt.Errorf("Invalid value / unknown config name: %s", value)
}
}
default:
// lazy init
if cfg.params == nil {
cfg.params = make(map[string]string)
}
if cfg.params[param[0]], err = url.QueryUnescape(value); err != nil {
return
}
}
}
return
}
// Returns the bool value of the input.
// The 2nd return value indicates if the input was a valid bool value
func readBool(input string) (value bool, valid bool) {
switch input {
case "1", "true", "TRUE", "True":
return true, true
case "0", "false", "FALSE", "False":
return false, true
}
// Not a valid bool value
return
}
/******************************************************************************
* Authentication *
******************************************************************************/
// Encrypt password using 4.1+ method
func scramblePassword(scramble, password []byte) []byte {
if len(password) == 0 {
return nil
}
// stage1Hash = SHA1(password)
crypt := sha1.New()
crypt.Write(password)
stage1 := crypt.Sum(nil)
// scrambleHash = SHA1(scramble + SHA1(stage1Hash))
// inner Hash
crypt.Reset()
crypt.Write(stage1)
hash := crypt.Sum(nil)
// outer Hash
crypt.Reset()
crypt.Write(scramble)
crypt.Write(hash)
scramble = crypt.Sum(nil)
// token = scrambleHash XOR stage1Hash
for i := range scramble {
scramble[i] ^= stage1[i]
}
return scramble
}
// Encrypt password using pre 4.1 (old password) method
// https://github.com/atcurtis/mariadb/blob/master/mysys/my_rnd.c
type myRnd struct {
seed1, seed2 uint32
}
const myRndMaxVal = 0x3FFFFFFF
// Pseudo random number generator
func newMyRnd(seed1, seed2 uint32) *myRnd {
return &myRnd{
seed1: seed1 % myRndMaxVal,
seed2: seed2 % myRndMaxVal,
}
}
// Tested to be equivalent to MariaDB's floating point variant
// http://play.golang.org/p/QHvhd4qved
// http://play.golang.org/p/RG0q4ElWDx
func (r *myRnd) NextByte() byte {
r.seed1 = (r.seed1*3 + r.seed2) % myRndMaxVal
r.seed2 = (r.seed1 + r.seed2 + 33) % myRndMaxVal
return byte(uint64(r.seed1) * 31 / myRndMaxVal)
}
// Generate binary hash from byte string using insecure pre 4.1 method
func pwHash(password []byte) (result [2]uint32) {
var add uint32 = 7
var tmp uint32
result[0] = 1345345333
result[1] = 0x12345671
for _, c := range password {
// skip spaces and tabs in password
if c == ' ' || c == '\t' {
continue
}
tmp = uint32(c)
result[0] ^= (((result[0] & 63) + add) * tmp) + (result[0] << 8)
result[1] += (result[1] << 8) ^ result[0]
add += tmp
}
// Remove sign bit (1<<31)-1)
result[0] &= 0x7FFFFFFF
result[1] &= 0x7FFFFFFF
return
}
// Encrypt password using insecure pre 4.1 method
func scrambleOldPassword(scramble, password []byte) []byte {
if len(password) == 0 {
return nil
}
scramble = scramble[:8]
hashPw := pwHash(password)
hashSc := pwHash(scramble)
r := newMyRnd(hashPw[0]^hashSc[0], hashPw[1]^hashSc[1])
var out [8]byte
for i := range out {
out[i] = r.NextByte() + 64
}
mask := r.NextByte()
for i := range out {
out[i] ^= mask
}
return out[:]
}
/******************************************************************************
* Time related utils *
******************************************************************************/
// NullTime represents a time.Time that may be NULL.
// NullTime implements the Scanner interface so
// it can be used as a scan destination:
//
// var nt NullTime
// err := db.QueryRow("SELECT time FROM foo WHERE id=?", id).Scan(&nt)
// ...
// if nt.Valid {
// // use nt.Time
// } else {
// // NULL value
// }
//
// This NullTime implementation is not driver-specific
type NullTime struct {
Time time.Time
Valid bool // Valid is true if Time is not NULL
}
// Scan implements the Scanner interface.
// The value type must be time.Time or string / []byte (formatted time-string),
// otherwise Scan fails.
func (nt *NullTime) Scan(value interface{}) (err error) {
if value == nil {
nt.Time, nt.Valid = time.Time{}, false
return
}
switch v := value.(type) {
case time.Time:
nt.Time, nt.Valid = v, true
return
case []byte:
nt.Time, err = parseDateTime(string(v), time.UTC)
nt.Valid = (err == nil)
return
case string:
nt.Time, err = parseDateTime(v, time.UTC)
nt.Valid = (err == nil)
return
}
nt.Valid = false
return fmt.Errorf("Can't convert %T to time.Time", value)
}
// Value implements the driver Valuer interface.
func (nt NullTime) Value() (driver.Value, error) {
if !nt.Valid {
return nil, nil
}
return nt.Time, nil
}
func parseDateTime(str string, loc *time.Location) (t time.Time, err error) {
base := "0000-00-00 00:00:00.0000000"
switch len(str) {
case 10, 19, 21, 22, 23, 24, 25, 26: // up to "YYYY-MM-DD HH:MM:SS.MMMMMM"
if str == base[:len(str)] {
return
}
t, err = time.Parse(timeFormat[:len(str)], str)
default:
err = fmt.Errorf("Invalid Time-String: %s", str)
return
}
// Adjust location
if err == nil && loc != time.UTC {
y, mo, d := t.Date()
h, mi, s := t.Clock()
t, err = time.Date(y, mo, d, h, mi, s, t.Nanosecond(), loc), nil
}
return
}
func parseBinaryDateTime(num uint64, data []byte, loc *time.Location) (driver.Value, error) {
switch num {
case 0:
return time.Time{}, nil
case 4:
return time.Date(
int(binary.LittleEndian.Uint16(data[:2])), // year
time.Month(data[2]), // month
int(data[3]), // day
0, 0, 0, 0,
loc,
), nil
case 7:
return time.Date(
int(binary.LittleEndian.Uint16(data[:2])), // year
time.Month(data[2]), // month
int(data[3]), // day
int(data[4]), // hour
int(data[5]), // minutes
int(data[6]), // seconds
0,
loc,
), nil
case 11:
return time.Date(
int(binary.LittleEndian.Uint16(data[:2])), // year
time.Month(data[2]), // month
int(data[3]), // day
int(data[4]), // hour
int(data[5]), // minutes
int(data[6]), // seconds
int(binary.LittleEndian.Uint32(data[7:11]))*1000, // nanoseconds
loc,
), nil
}
return nil, fmt.Errorf("Invalid DATETIME-packet length %d", num)
}
// zeroDateTime is used in formatBinaryDateTime to avoid an allocation
// if the DATE or DATETIME has the zero value.
// It must never be changed.
// The current behavior depends on database/sql copying the result.
var zeroDateTime = []byte("0000-00-00 00:00:00.000000")
const digits01 = "0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789"
const digits10 = "0000000000111111111122222222223333333333444444444455555555556666666666777777777788888888889999999999"
func formatBinaryDateTime(src []byte, length uint8, justTime bool) (driver.Value, error) {
// length expects the deterministic length of the zero value,
// negative time and 100+ hours are automatically added if needed
if len(src) == 0 {
if justTime {
return zeroDateTime[11 : 11+length], nil
}
return zeroDateTime[:length], nil
}
var dst []byte // return value
var pt, p1, p2, p3 byte // current digit pair
var zOffs byte // offset of value in zeroDateTime
if justTime {
switch length {
case
8, // time (can be up to 10 when negative and 100+ hours)
10, 11, 12, 13, 14, 15: // time with fractional seconds
default:
return nil, fmt.Errorf("illegal TIME length %d", length)
}
switch len(src) {
case 8, 12:
default:
return nil, fmt.Errorf("Invalid TIME-packet length %d", len(src))
}
// +2 to enable negative time and 100+ hours
dst = make([]byte, 0, length+2)
if src[0] == 1 {
dst = append(dst, '-')
}
if src[1] != 0 {
hour := uint16(src[1])*24 + uint16(src[5])
pt = byte(hour / 100)
p1 = byte(hour - 100*uint16(pt))
dst = append(dst, digits01[pt])
} else {
p1 = src[5]
}
zOffs = 11
src = src[6:]
} else {
switch length {
case 10, 19, 21, 22, 23, 24, 25, 26:
default:
t := "DATE"
if length > 10 {
t += "TIME"
}
return nil, fmt.Errorf("illegal %s length %d", t, length)
}
switch len(src) {
case 4, 7, 11:
default:
t := "DATE"
if length > 10 {
t += "TIME"
}
return nil, fmt.Errorf("illegal %s-packet length %d", t, len(src))
}
dst = make([]byte, 0, length)
// start with the date
year := binary.LittleEndian.Uint16(src[:2])
pt = byte(year / 100)
p1 = byte(year - 100*uint16(pt))
p2, p3 = src[2], src[3]
dst = append(dst,
digits10[pt], digits01[pt],
digits10[p1], digits01[p1], '-',
digits10[p2], digits01[p2], '-',
digits10[p3], digits01[p3],
)
if length == 10 {
return dst, nil
}
if len(src) == 4 {
return append(dst, zeroDateTime[10:length]...), nil
}
dst = append(dst, ' ')
p1 = src[4] // hour
src = src[5:]
}
// p1 is 2-digit hour, src is after hour
p2, p3 = src[0], src[1]
dst = append(dst,
digits10[p1], digits01[p1], ':',
digits10[p2], digits01[p2], ':',
digits10[p3], digits01[p3],
)
if length <= byte(len(dst)) {
return dst, nil
}
src = src[2:]
if len(src) == 0 {
return append(dst, zeroDateTime[19:zOffs+length]...), nil
}
microsecs := binary.LittleEndian.Uint32(src[:4])
p1 = byte(microsecs / 10000)
microsecs -= 10000 * uint32(p1)
p2 = byte(microsecs / 100)
microsecs -= 100 * uint32(p2)
p3 = byte(microsecs)
switch decimals := zOffs + length - 20; decimals {
default:
return append(dst, '.',
digits10[p1], digits01[p1],
digits10[p2], digits01[p2],
digits10[p3], digits01[p3],
), nil
case 1:
return append(dst, '.',
digits10[p1],
), nil
case 2:
return append(dst, '.',
digits10[p1], digits01[p1],
), nil
case 3:
return append(dst, '.',
digits10[p1], digits01[p1],
digits10[p2],
), nil
case 4:
return append(dst, '.',
digits10[p1], digits01[p1],
digits10[p2], digits01[p2],
), nil
case 5:
return append(dst, '.',
digits10[p1], digits01[p1],
digits10[p2], digits01[p2],
digits10[p3],
), nil
}
}
/******************************************************************************
* Convert from and to bytes *
******************************************************************************/
func uint64ToBytes(n uint64) []byte {
return []byte{
byte(n),
byte(n >> 8),
byte(n >> 16),
byte(n >> 24),
byte(n >> 32),
byte(n >> 40),
byte(n >> 48),
byte(n >> 56),
}
}
func uint64ToString(n uint64) []byte {
var a [20]byte
i := 20
// U+0030 = 0
// ...
// U+0039 = 9
var q uint64
for n >= 10 {
i--
q = n / 10
a[i] = uint8(n-q*10) + 0x30
n = q
}
i--
a[i] = uint8(n) + 0x30
return a[i:]
}
// treats string value as unsigned integer representation
func stringToInt(b []byte) int {
val := 0
for i := range b {
val *= 10
val += int(b[i] - 0x30)
}
return val
}
// returns the string read as a bytes slice, wheter the value is NULL,
// the number of bytes read and an error, in case the string is longer than
// the input slice
func readLengthEncodedString(b []byte) ([]byte, bool, int, error) {
// Get length
num, isNull, n := readLengthEncodedInteger(b)
if num < 1 {
return b[n:n], isNull, n, nil
}
n += int(num)
// Check data length
if len(b) >= n {
return b[n-int(num) : n], false, n, nil
}
return nil, false, n, io.EOF
}
// returns the number of bytes skipped and an error, in case the string is
// longer than the input slice
func skipLengthEncodedString(b []byte) (int, error) {
// Get length
num, _, n := readLengthEncodedInteger(b)
if num < 1 {
return n, nil
}
n += int(num)
// Check data length
if len(b) >= n {
return n, nil
}
return n, io.EOF
}
// returns the number read, whether the value is NULL and the number of bytes read
func readLengthEncodedInteger(b []byte) (uint64, bool, int) {
// See issue #349
if len(b) == 0 {
return 0, true, 1
}
switch b[0] {
// 251: NULL
case 0xfb:
return 0, true, 1
// 252: value of following 2
case 0xfc:
return uint64(b[1]) | uint64(b[2])<<8, false, 3
// 253: value of following 3
case 0xfd:
return uint64(b[1]) | uint64(b[2])<<8 | uint64(b[3])<<16, false, 4
// 254: value of following 8
case 0xfe:
return uint64(b[1]) | uint64(b[2])<<8 | uint64(b[3])<<16 |
uint64(b[4])<<24 | uint64(b[5])<<32 | uint64(b[6])<<40 |
uint64(b[7])<<48 | uint64(b[8])<<56,
false, 9
}
// 0-250: value of first byte
return uint64(b[0]), false, 1
}
// encodes a uint64 value and appends it to the given bytes slice
func appendLengthEncodedInteger(b []byte, n uint64) []byte {
switch {
case n <= 250:
return append(b, byte(n))
case n <= 0xffff:
return append(b, 0xfc, byte(n), byte(n>>8))
case n <= 0xffffff:
return append(b, 0xfd, byte(n), byte(n>>8), byte(n>>16))
}
return append(b, 0xfe, byte(n), byte(n>>8), byte(n>>16), byte(n>>24),
byte(n>>32), byte(n>>40), byte(n>>48), byte(n>>56))
}
// reserveBuffer checks cap(buf) and expand buffer to len(buf) + appendSize.
// If cap(buf) is not enough, reallocate new buffer.
func reserveBuffer(buf []byte, appendSize int) []byte {
newSize := len(buf) + appendSize
if cap(buf) < newSize {
// Grow buffer exponentially
newBuf := make([]byte, len(buf)*2+appendSize)
copy(newBuf, buf)
buf = newBuf
}
return buf[:newSize]
}
// escapeBytesBackslash escapes []byte with backslashes (\)
// This escapes the contents of a string (provided as []byte) by adding backslashes before special
// characters, and turning others into specific escape sequences, such as
// turning newlines into \n and null bytes into \0.
// https://github.com/mysql/mysql-server/blob/mysql-5.7.5/mysys/charset.c#L823-L932
func escapeBytesBackslash(buf, v []byte) []byte {
pos := len(buf)
buf = reserveBuffer(buf, len(v)*2)
for _, c := range v {
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 += 1
}
}
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 += 1
}
}
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]
}