harbor/vendor/github.com/go-sql-driver/mysql/connection.go
2016-08-12 14:50:00 +08:00

267 lines
5.4 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/tls"
"database/sql/driver"
"errors"
"net"
"strings"
"time"
)
type mysqlConn struct {
buf buffer
netConn net.Conn
affectedRows uint64
insertId uint64
cfg *config
maxPacketAllowed int
maxWriteSize int
flags clientFlag
sequence uint8
parseTime bool
strict bool
}
type config struct {
user string
passwd string
net string
addr string
dbname string
params map[string]string
loc *time.Location
tls *tls.Config
timeout time.Duration
collation uint8
allowAllFiles bool
allowOldPasswords bool
clientFoundRows bool
}
// Handles parameters set in DSN after the connection is established
func (mc *mysqlConn) handleParams() (err error) {
for param, val := range mc.cfg.params {
switch param {
// Charset
case "charset":
charsets := strings.Split(val, ",")
for i := range charsets {
// ignore errors here - a charset may not exist
err = mc.exec("SET NAMES " + charsets[i])
if err == nil {
break
}
}
if err != nil {
return
}
// time.Time parsing
case "parseTime":
var isBool bool
mc.parseTime, isBool = readBool(val)
if !isBool {
return errors.New("Invalid Bool value: " + val)
}
// Strict mode
case "strict":
var isBool bool
mc.strict, isBool = readBool(val)
if !isBool {
return errors.New("Invalid Bool value: " + val)
}
// Compression
case "compress":
err = errors.New("Compression not implemented yet")
return
// System Vars
default:
err = mc.exec("SET " + param + "=" + val + "")
if err != nil {
return
}
}
}
return
}
func (mc *mysqlConn) Begin() (driver.Tx, error) {
if mc.netConn == nil {
errLog.Print(ErrInvalidConn)
return nil, driver.ErrBadConn
}
err := mc.exec("START TRANSACTION")
if err == nil {
return &mysqlTx{mc}, err
}
return nil, err
}
func (mc *mysqlConn) Close() (err error) {
// Makes Close idempotent
if mc.netConn != nil {
err = mc.writeCommandPacket(comQuit)
if err == nil {
err = mc.netConn.Close()
} else {
mc.netConn.Close()
}
mc.netConn = nil
}
mc.cfg = nil
mc.buf.rd = nil
return
}
func (mc *mysqlConn) Prepare(query string) (driver.Stmt, error) {
if mc.netConn == nil {
errLog.Print(ErrInvalidConn)
return nil, driver.ErrBadConn
}
// Send command
err := mc.writeCommandPacketStr(comStmtPrepare, query)
if err != nil {
return nil, err
}
stmt := &mysqlStmt{
mc: mc,
}
// Read Result
columnCount, err := stmt.readPrepareResultPacket()
if err == nil {
if stmt.paramCount > 0 {
if err = mc.readUntilEOF(); err != nil {
return nil, err
}
}
if columnCount > 0 {
err = mc.readUntilEOF()
}
}
return stmt, err
}
func (mc *mysqlConn) Exec(query string, args []driver.Value) (driver.Result, error) {
if mc.netConn == nil {
errLog.Print(ErrInvalidConn)
return nil, driver.ErrBadConn
}
if len(args) == 0 { // no args, fastpath
mc.affectedRows = 0
mc.insertId = 0
err := mc.exec(query)
if err == nil {
return &mysqlResult{
affectedRows: int64(mc.affectedRows),
insertId: int64(mc.insertId),
}, err
}
return nil, err
}
// with args, must use prepared stmt
return nil, driver.ErrSkip
}
// Internal function to execute commands
func (mc *mysqlConn) exec(query string) error {
// Send command
err := mc.writeCommandPacketStr(comQuery, query)
if err != nil {
return err
}
// Read Result
resLen, err := mc.readResultSetHeaderPacket()
if err == nil && resLen > 0 {
if err = mc.readUntilEOF(); err != nil {
return err
}
err = mc.readUntilEOF()
}
return err
}
func (mc *mysqlConn) Query(query string, args []driver.Value) (driver.Rows, error) {
if mc.netConn == nil {
errLog.Print(ErrInvalidConn)
return nil, driver.ErrBadConn
}
if len(args) == 0 { // no args, fastpath
// Send command
err := mc.writeCommandPacketStr(comQuery, query)
if err == nil {
// Read Result
var resLen int
resLen, err = mc.readResultSetHeaderPacket()
if err == nil {
rows := new(textRows)
rows.mc = mc
if resLen > 0 {
// Columns
rows.columns, err = mc.readColumns(resLen)
}
return rows, err
}
}
return nil, err
}
// with args, must use prepared stmt
return nil, driver.ErrSkip
}
// Gets the value of the given MySQL System Variable
// The returned byte slice is only valid until the next read
func (mc *mysqlConn) getSystemVar(name string) ([]byte, error) {
// Send command
if err := mc.writeCommandPacketStr(comQuery, "SELECT @@"+name); err != nil {
return nil, err
}
// Read Result
resLen, err := mc.readResultSetHeaderPacket()
if err == nil {
rows := new(textRows)
rows.mc = mc
if resLen > 0 {
// Columns
if err := mc.readUntilEOF(); err != nil {
return nil, err
}
}
dest := make([]driver.Value, resLen)
if err = rows.readRow(dest); err == nil {
return dest[0].([]byte), mc.readUntilEOF()
}
}
return nil, err
}