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packets.go
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packets.go
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// 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 (
"bytes"
"crypto/tls"
"database/sql/driver"
"encoding/binary"
"fmt"
"io"
"math"
"time"
)
// Packets documentation:
// http://dev.mysql.com/doc/internals/en/client-server-protocol.html
// Read packet to buffer 'data'
func (mc *mysqlConn) readPacket() ([]byte, error) {
var payload []byte
for {
// Read packet header
data, err := mc.buf.readNext(4)
if err != nil {
errLog.Print(err)
mc.Close()
return nil, driver.ErrBadConn
}
// Packet Length [24 bit]
pktLen := int(uint32(data[0]) | uint32(data[1])<<8 | uint32(data[2])<<16)
if pktLen < 1 {
errLog.Print(ErrMalformPkt)
mc.Close()
return nil, driver.ErrBadConn
}
// Check Packet Sync [8 bit]
if data[3] != mc.sequence {
if data[3] > mc.sequence {
return nil, ErrPktSyncMul
} else {
return nil, ErrPktSync
}
}
mc.sequence++
// Read packet body [pktLen bytes]
data, err = mc.buf.readNext(pktLen)
if err != nil {
errLog.Print(err)
mc.Close()
return nil, driver.ErrBadConn
}
isLastPacket := (pktLen < maxPacketSize)
// Zero allocations for non-splitting packets
if isLastPacket && payload == nil {
return data, nil
}
payload = append(payload, data...)
if isLastPacket {
return payload, nil
}
}
}
// Write packet buffer 'data'
func (mc *mysqlConn) writePacket(data []byte) error {
pktLen := len(data) - 4
if pktLen > mc.maxPacketAllowed {
return ErrPktTooLarge
}
for {
var size int
if pktLen >= maxPacketSize {
data[0] = 0xff
data[1] = 0xff
data[2] = 0xff
size = maxPacketSize
} else {
data[0] = byte(pktLen)
data[1] = byte(pktLen >> 8)
data[2] = byte(pktLen >> 16)
size = pktLen
}
data[3] = mc.sequence
// Write packet
n, err := mc.netConn.Write(data[:4+size])
if err == nil && n == 4+size {
mc.sequence++
if size != maxPacketSize {
return nil
}
pktLen -= size
data = data[size:]
continue
}
// Handle error
if err == nil { // n != len(data)
errLog.Print(ErrMalformPkt)
} else {
errLog.Print(err)
}
return driver.ErrBadConn
}
}
/******************************************************************************
* Initialisation Process *
******************************************************************************/
// Handshake Initialization Packet
// http://dev.mysql.com/doc/internals/en/connection-phase-packets.html#packet-Protocol::Handshake
func (mc *mysqlConn) readInitPacket() ([]byte, error) {
data, err := mc.readPacket()
if err != nil {
return nil, err
}
if data[0] == iERR {
return nil, mc.handleErrorPacket(data)
}
// protocol version [1 byte]
if data[0] < minProtocolVersion {
return nil, fmt.Errorf(
"Unsupported MySQL Protocol Version %d. Protocol Version %d or higher is required",
data[0],
minProtocolVersion,
)
}
// server version [null terminated string]
// connection id [4 bytes]
pos := 1 + bytes.IndexByte(data[1:], 0x00) + 1 + 4
// first part of the password cipher [8 bytes]
cipher := data[pos : pos+8]
// (filler) always 0x00 [1 byte]
pos += 8 + 1
// capability flags (lower 2 bytes) [2 bytes]
mc.flags = clientFlag(binary.LittleEndian.Uint16(data[pos : pos+2]))
if mc.flags&clientProtocol41 == 0 {
return nil, ErrOldProtocol
}
if mc.flags&clientSSL == 0 && mc.cfg.tls != nil {
return nil, ErrNoTLS
}
pos += 2
if len(data) > pos {
// character set [1 byte]
// status flags [2 bytes]
// capability flags (upper 2 bytes) [2 bytes]
// length of auth-plugin-data [1 byte]
// reserved (all [00]) [10 bytes]
pos += 1 + 2 + 2 + 1 + 10
// second part of the password cipher [mininum 13 bytes],
// where len=MAX(13, length of auth-plugin-data - 8)
//
// The web documentation is ambiguous about the length. However,
// according to mysql-5.7/sql/auth/sql_authentication.cc line 538,
// the 13th byte is "\0 byte, terminating the second part of
// a scramble". So the second part of the password cipher is
// a NULL terminated string that's at least 13 bytes with the
// last byte being NULL.
//
// The official Python library uses the fixed length 12
// which seems to work but technically could have a hidden bug.
cipher = append(cipher, data[pos:pos+12]...)
// TODO: Verify string termination
// EOF if version (>= 5.5.7 and < 5.5.10) or (>= 5.6.0 and < 5.6.2)
// \NUL otherwise
//
//if data[len(data)-1] == 0 {
// return
//}
//return ErrMalformPkt
// make a memory safe copy of the cipher slice
var b [20]byte
copy(b[:], cipher)
return b[:], nil
}
// make a memory safe copy of the cipher slice
var b [8]byte
copy(b[:], cipher)
return b[:], nil
}
// Client Authentication Packet
// http://dev.mysql.com/doc/internals/en/connection-phase-packets.html#packet-Protocol::HandshakeResponse
func (mc *mysqlConn) writeAuthPacket(cipher []byte) error {
// Adjust client flags based on server support
clientFlags := clientProtocol41 |
clientSecureConn |
clientLongPassword |
clientTransactions |
clientLocalFiles |
clientPluginAuth |
mc.flags&clientLongFlag
if mc.cfg.clientFoundRows {
clientFlags |= clientFoundRows
}
// To enable TLS / SSL
if mc.cfg.tls != nil {
clientFlags |= clientSSL
}
// User Password
scrambleBuff := scramblePassword(cipher, []byte(mc.cfg.passwd))
pktLen := 4 + 4 + 1 + 23 + len(mc.cfg.user) + 1 + 1 + len(scrambleBuff) + 21 + 1
// To specify a db name
if n := len(mc.cfg.dbname); n > 0 {
clientFlags |= clientConnectWithDB
pktLen += n + 1
}
// Calculate packet length and get buffer with that size
data := mc.buf.takeSmallBuffer(pktLen + 4)
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// ClientFlags [32 bit]
data[4] = byte(clientFlags)
data[5] = byte(clientFlags >> 8)
data[6] = byte(clientFlags >> 16)
data[7] = byte(clientFlags >> 24)
// MaxPacketSize [32 bit] (none)
data[8] = 0x00
data[9] = 0x00
data[10] = 0x00
data[11] = 0x00
// Charset [1 byte]
data[12] = mc.cfg.collation
// SSL Connection Request Packet
// http://dev.mysql.com/doc/internals/en/connection-phase-packets.html#packet-Protocol::SSLRequest
if mc.cfg.tls != nil {
// Send TLS / SSL request packet
if err := mc.writePacket(data[:(4+4+1+23)+4]); err != nil {
return err
}
// Switch to TLS
tlsConn := tls.Client(mc.netConn, mc.cfg.tls)
if err := tlsConn.Handshake(); err != nil {
return err
}
mc.netConn = tlsConn
mc.buf.rd = tlsConn
}
// Filler [23 bytes] (all 0x00)
pos := 13 + 23
// User [null terminated string]
if len(mc.cfg.user) > 0 {
pos += copy(data[pos:], mc.cfg.user)
}
data[pos] = 0x00
pos++
// ScrambleBuffer [length encoded integer]
data[pos] = byte(len(scrambleBuff))
pos += 1 + copy(data[pos+1:], scrambleBuff)
// Databasename [null terminated string]
if len(mc.cfg.dbname) > 0 {
pos += copy(data[pos:], mc.cfg.dbname)
data[pos] = 0x00
pos++
}
// Assume native client during response
pos += copy(data[pos:], "mysql_native_password")
data[pos] = 0x00
// Send Auth packet
return mc.writePacket(data)
}
// Client old authentication packet
// http://dev.mysql.com/doc/internals/en/connection-phase-packets.html#packet-Protocol::AuthSwitchResponse
func (mc *mysqlConn) writeOldAuthPacket(cipher []byte) error {
// User password
scrambleBuff := scrambleOldPassword(cipher, []byte(mc.cfg.passwd))
// Calculate the packet length and add a tailing 0
pktLen := len(scrambleBuff) + 1
data := mc.buf.takeSmallBuffer(4 + pktLen)
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// Add the scrambled password [null terminated string]
copy(data[4:], scrambleBuff)
data[4+pktLen-1] = 0x00
return mc.writePacket(data)
}
// Client clear text authentication packet
// http://dev.mysql.com/doc/internals/en/connection-phase-packets.html#packet-Protocol::AuthSwitchResponse
func (mc *mysqlConn) writeClearAuthPacket() error {
// Calculate the packet length and add a tailing 0
pktLen := len(mc.cfg.passwd) + 1
data := mc.buf.takeSmallBuffer(4 + pktLen)
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// Add the clear password [null terminated string]
copy(data[4:], mc.cfg.passwd)
data[4+pktLen-1] = 0x00
return mc.writePacket(data)
}
/******************************************************************************
* Command Packets *
******************************************************************************/
func (mc *mysqlConn) writeCommandPacket(command byte) error {
// Reset Packet Sequence
mc.sequence = 0
data := mc.buf.takeSmallBuffer(4 + 1)
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// Add command byte
data[4] = command
// Send CMD packet
return mc.writePacket(data)
}
func (mc *mysqlConn) writeCommandPacketStr(command byte, arg string) error {
// Reset Packet Sequence
mc.sequence = 0
pktLen := 1 + len(arg)
data := mc.buf.takeBuffer(pktLen + 4)
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// Add command byte
data[4] = command
// Add arg
copy(data[5:], arg)
// Send CMD packet
return mc.writePacket(data)
}
func (mc *mysqlConn) writeCommandPacketUint32(command byte, arg uint32) error {
// Reset Packet Sequence
mc.sequence = 0
data := mc.buf.takeSmallBuffer(4 + 1 + 4)
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// Add command byte
data[4] = command
// Add arg [32 bit]
data[5] = byte(arg)
data[6] = byte(arg >> 8)
data[7] = byte(arg >> 16)
data[8] = byte(arg >> 24)
// Send CMD packet
return mc.writePacket(data)
}
/******************************************************************************
* Result Packets *
******************************************************************************/
// Returns error if Packet is not an 'Result OK'-Packet
func (mc *mysqlConn) readResultOK() error {
data, err := mc.readPacket()
if err == nil {
// packet indicator
switch data[0] {
case iOK:
return mc.handleOkPacket(data)
case iEOF:
if len(data) > 1 {
plugin := string(data[1:bytes.IndexByte(data, 0x00)])
if plugin == "mysql_old_password" {
// using old_passwords
return ErrOldPassword
} else if plugin == "mysql_clear_password" {
// using clear text password
return ErrCleartextPassword
} else {
return ErrUnknownPlugin
}
} else {
return ErrOldPassword
}
default: // Error otherwise
return mc.handleErrorPacket(data)
}
}
return err
}
// Result Set Header Packet
// http://dev.mysql.com/doc/internals/en/com-query-response.html#packet-ProtocolText::Resultset
func (mc *mysqlConn) readResultSetHeaderPacket() (int, error) {
data, err := mc.readPacket()
if err == nil {
switch data[0] {
case iOK:
return 0, mc.handleOkPacket(data)
case iERR:
return 0, mc.handleErrorPacket(data)
case iLocalInFile:
return 0, mc.handleInFileRequest(string(data[1:]))
}
// column count
num, _, n := readLengthEncodedInteger(data)
if n-len(data) == 0 {
return int(num), nil
}
return 0, ErrMalformPkt
}
return 0, err
}
// Error Packet
// http://dev.mysql.com/doc/internals/en/generic-response-packets.html#packet-ERR_Packet
func (mc *mysqlConn) handleErrorPacket(data []byte) error {
if data[0] != iERR {
return ErrMalformPkt
}
// 0xff [1 byte]
// Error Number [16 bit uint]
errno := binary.LittleEndian.Uint16(data[1:3])
pos := 3
// SQL State [optional: # + 5bytes string]
if data[3] == 0x23 {
//sqlstate := string(data[4 : 4+5])
pos = 9
}
// Error Message [string]
return &MySQLError{
Number: errno,
Message: string(data[pos:]),
}
}
// Ok Packet
// http://dev.mysql.com/doc/internals/en/generic-response-packets.html#packet-OK_Packet
func (mc *mysqlConn) handleOkPacket(data []byte) error {
var n, m int
// 0x00 [1 byte]
// Affected rows [Length Coded Binary]
mc.affectedRows, _, n = readLengthEncodedInteger(data[1:])
// Insert id [Length Coded Binary]
mc.insertId, _, m = readLengthEncodedInteger(data[1+n:])
// server_status [2 bytes]
mc.status = statusFlag(data[1+n+m]) | statusFlag(data[1+n+m+1])<<8
// warning count [2 bytes]
if !mc.strict {
return nil
} else {
pos := 1 + n + m + 2
if binary.LittleEndian.Uint16(data[pos:pos+2]) > 0 {
return mc.getWarnings()
}
return nil
}
}
// Read Packets as Field Packets until EOF-Packet or an Error appears
// http://dev.mysql.com/doc/internals/en/com-query-response.html#packet-Protocol::ColumnDefinition41
func (mc *mysqlConn) readColumns(count int) ([]mysqlField, error) {
columns := make([]mysqlField, count)
for i := 0; ; i++ {
data, err := mc.readPacket()
if err != nil {
return nil, err
}
// EOF Packet
if data[0] == iEOF && (len(data) == 5 || len(data) == 1) {
if i == count {
return columns, nil
}
return nil, fmt.Errorf("ColumnsCount mismatch n:%d len:%d", count, len(columns))
}
// Catalog
pos, err := skipLengthEncodedString(data)
if err != nil {
return nil, err
}
// Database [len coded string]
n, err := skipLengthEncodedString(data[pos:])
if err != nil {
return nil, err
}
pos += n
// Table [len coded string]
if mc.cfg.columnsWithAlias {
tableName, _, n, err := readLengthEncodedString(data[pos:])
if err != nil {
return nil, err
}
pos += n
columns[i].tableName = string(tableName)
} else {
n, err = skipLengthEncodedString(data[pos:])
if err != nil {
return nil, err
}
pos += n
}
// Original table [len coded string]
n, err = skipLengthEncodedString(data[pos:])
if err != nil {
return nil, err
}
pos += n
// Name [len coded string]
name, _, n, err := readLengthEncodedString(data[pos:])
if err != nil {
return nil, err
}
columns[i].name = string(name)
pos += n
// Original name [len coded string]
n, err = skipLengthEncodedString(data[pos:])
if err != nil {
return nil, err
}
// Filler [uint8]
// Charset [charset, collation uint8]
// Length [uint32]
pos += n + 1 + 2 + 4
// Field type [uint8]
columns[i].fieldType = data[pos]
pos++
// Flags [uint16]
columns[i].flags = fieldFlag(binary.LittleEndian.Uint16(data[pos : pos+2]))
pos += 2
// Decimals [uint8]
columns[i].decimals = data[pos]
//pos++
// Default value [len coded binary]
//if pos < len(data) {
// defaultVal, _, err = bytesToLengthCodedBinary(data[pos:])
//}
}
}
// Read Packets as Field Packets until EOF-Packet or an Error appears
// http://dev.mysql.com/doc/internals/en/com-query-response.html#packet-ProtocolText::ResultsetRow
func (rows *textRows) readRow(dest []driver.Value) error {
mc := rows.mc
data, err := mc.readPacket()
if err != nil {
return err
}
// EOF Packet
if data[0] == iEOF && len(data) == 5 {
rows.mc = nil
return io.EOF
}
if data[0] == iERR {
rows.mc = nil
return mc.handleErrorPacket(data)
}
// RowSet Packet
var n int
var isNull bool
pos := 0
for i := range dest {
// Read bytes and convert to string
dest[i], isNull, n, err = readLengthEncodedString(data[pos:])
pos += n
if err == nil {
if !isNull {
if !mc.parseTime {
continue
} else {
switch rows.columns[i].fieldType {
case fieldTypeTimestamp, fieldTypeDateTime,
fieldTypeDate, fieldTypeNewDate:
dest[i], err = parseDateTime(
string(dest[i].([]byte)),
mc.cfg.loc,
)
if err == nil {
continue
}
default:
continue
}
}
} else {
dest[i] = nil
continue
}
}
return err // err != nil
}
return nil
}
// Reads Packets until EOF-Packet or an Error appears. Returns count of Packets read
func (mc *mysqlConn) readUntilEOF() error {
for {
data, err := mc.readPacket()
// No Err and no EOF Packet
if err == nil && data[0] != iEOF {
continue
}
return err // Err or EOF
}
}
/******************************************************************************
* Prepared Statements *
******************************************************************************/
// Prepare Result Packets
// http://dev.mysql.com/doc/internals/en/com-stmt-prepare-response.html
func (stmt *mysqlStmt) readPrepareResultPacket() (uint16, error) {
data, err := stmt.mc.readPacket()
if err == nil {
// packet indicator [1 byte]
if data[0] != iOK {
return 0, stmt.mc.handleErrorPacket(data)
}
// statement id [4 bytes]
stmt.id = binary.LittleEndian.Uint32(data[1:5])
// Column count [16 bit uint]
columnCount := binary.LittleEndian.Uint16(data[5:7])
// Param count [16 bit uint]
stmt.paramCount = int(binary.LittleEndian.Uint16(data[7:9]))
// Reserved [8 bit]
// Warning count [16 bit uint]
if !stmt.mc.strict {
return columnCount, nil
} else {
// Check for warnings count > 0, only available in MySQL > 4.1
if len(data) >= 12 && binary.LittleEndian.Uint16(data[10:12]) > 0 {
return columnCount, stmt.mc.getWarnings()
}
return columnCount, nil
}
}
return 0, err
}
// http://dev.mysql.com/doc/internals/en/com-stmt-send-long-data.html
func (stmt *mysqlStmt) writeCommandLongData(paramID int, arg []byte) error {
maxLen := stmt.mc.maxPacketAllowed - 1
pktLen := maxLen
// After the header (bytes 0-3) follows before the data:
// 1 byte command
// 4 bytes stmtID
// 2 bytes paramID
const dataOffset = 1 + 4 + 2
// Can not use the write buffer since
// a) the buffer is too small
// b) it is in use
data := make([]byte, 4+1+4+2+len(arg))
copy(data[4+dataOffset:], arg)
for argLen := len(arg); argLen > 0; argLen -= pktLen - dataOffset {
if dataOffset+argLen < maxLen {
pktLen = dataOffset + argLen
}
stmt.mc.sequence = 0
// Add command byte [1 byte]
data[4] = comStmtSendLongData
// Add stmtID [32 bit]
data[5] = byte(stmt.id)
data[6] = byte(stmt.id >> 8)
data[7] = byte(stmt.id >> 16)
data[8] = byte(stmt.id >> 24)
// Add paramID [16 bit]
data[9] = byte(paramID)
data[10] = byte(paramID >> 8)
// Send CMD packet
err := stmt.mc.writePacket(data[:4+pktLen])
if err == nil {
data = data[pktLen-dataOffset:]
continue
}
return err
}
// Reset Packet Sequence
stmt.mc.sequence = 0
return nil
}
// Execute Prepared Statement
// http://dev.mysql.com/doc/internals/en/com-stmt-execute.html
func (stmt *mysqlStmt) writeExecutePacket(args []driver.Value) error {
if len(args) != stmt.paramCount {
return fmt.Errorf(
"Arguments count mismatch (Got: %d Has: %d)",
len(args),
stmt.paramCount,
)
}
const minPktLen = 4 + 1 + 4 + 1 + 4
mc := stmt.mc
// Reset packet-sequence
mc.sequence = 0
var data []byte
if len(args) == 0 {
data = mc.buf.takeBuffer(minPktLen)
} else {
data = mc.buf.takeCompleteBuffer()
}
if data == nil {
// can not take the buffer. Something must be wrong with the connection
errLog.Print(ErrBusyBuffer)
return driver.ErrBadConn
}
// command [1 byte]
data[4] = comStmtExecute
// statement_id [4 bytes]
data[5] = byte(stmt.id)
data[6] = byte(stmt.id >> 8)
data[7] = byte(stmt.id >> 16)
data[8] = byte(stmt.id >> 24)
// flags (0: CURSOR_TYPE_NO_CURSOR) [1 byte]
data[9] = 0x00
// iteration_count (uint32(1)) [4 bytes]
data[10] = 0x01
data[11] = 0x00
data[12] = 0x00
data[13] = 0x00
if len(args) > 0 {
pos := minPktLen
var nullMask []byte
if maskLen, typesLen := (len(args)+7)/8, 1+2*len(args); pos+maskLen+typesLen >= len(data) {
// buffer has to be extended but we don't know by how much so
// we depend on append after all data with known sizes fit.
// We stop at that because we deal with a lot of columns here
// which makes the required allocation size hard to guess.
tmp := make([]byte, pos+maskLen+typesLen)
copy(tmp[:pos], data[:pos])
data = tmp
nullMask = data[pos : pos+maskLen]
pos += maskLen
} else {
nullMask = data[pos : pos+maskLen]
for i := 0; i < maskLen; i++ {
nullMask[i] = 0
}
pos += maskLen
}
// newParameterBoundFlag 1 [1 byte]
data[pos] = 0x01
pos++
// type of each parameter [len(args)*2 bytes]
paramTypes := data[pos:]
pos += len(args) * 2
// value of each parameter [n bytes]
paramValues := data[pos:pos]
valuesCap := cap(paramValues)
for i, arg := range args {
// build NULL-bitmap
if arg == nil {
nullMask[i/8] |= 1 << (uint(i) & 7)
paramTypes[i+i] = fieldTypeNULL
paramTypes[i+i+1] = 0x00
continue
}
// cache types and values
switch v := arg.(type) {
case int64:
paramTypes[i+i] = fieldTypeLongLong
paramTypes[i+i+1] = 0x00
if cap(paramValues)-len(paramValues)-8 >= 0 {
paramValues = paramValues[:len(paramValues)+8]
binary.LittleEndian.PutUint64(
paramValues[len(paramValues)-8:],
uint64(v),
)
} else {
paramValues = append(paramValues,
uint64ToBytes(uint64(v))...,
)
}
case float64:
paramTypes[i+i] = fieldTypeDouble
paramTypes[i+i+1] = 0x00
if cap(paramValues)-len(paramValues)-8 >= 0 {
paramValues = paramValues[:len(paramValues)+8]
binary.LittleEndian.PutUint64(
paramValues[len(paramValues)-8:],
math.Float64bits(v),
)
} else {
paramValues = append(paramValues,
uint64ToBytes(math.Float64bits(v))...,
)
}
case bool:
paramTypes[i+i] = fieldTypeTiny
paramTypes[i+i+1] = 0x00
if v {
paramValues = append(paramValues, 0x01)
} else {
paramValues = append(paramValues, 0x00)
}
case []byte:
// Common case (non-nil value) first
if v != nil {
paramTypes[i+i] = fieldTypeString
paramTypes[i+i+1] = 0x00
if len(v) < mc.maxPacketAllowed-pos-len(paramValues)-(len(args)-(i+1))*64 {
paramValues = appendLengthEncodedInteger(paramValues,
uint64(len(v)),
)
paramValues = append(paramValues, v...)
} else {
if err := stmt.writeCommandLongData(i, v); err != nil {
return err
}
}
continue
}
// Handle []byte(nil) as a NULL value
nullMask[i/8] |= 1 << (uint(i) & 7)
paramTypes[i+i] = fieldTypeNULL
paramTypes[i+i+1] = 0x00
case string:
paramTypes[i+i] = fieldTypeString
paramTypes[i+i+1] = 0x00
if len(v) < mc.maxPacketAllowed-pos-len(paramValues)-(len(args)-(i+1))*64 {
paramValues = appendLengthEncodedInteger(paramValues,
uint64(len(v)),
)
paramValues = append(paramValues, v...)
} else {
if err := stmt.writeCommandLongData(i, []byte(v)); err != nil {
return err
}
}
case time.Time:
paramTypes[i+i] = fieldTypeString
paramTypes[i+i+1] = 0x00
var val []byte
if v.IsZero() {
val = []byte("0000-00-00")
} else {
val = []byte(v.In(mc.cfg.loc).Format(timeFormat))
}
paramValues = appendLengthEncodedInteger(paramValues,
uint64(len(val)),
)
paramValues = append(paramValues, val...)
default:
return fmt.Errorf("Can't convert type: %T", arg)
}
}
// Check if param values exceeded the available buffer
// In that case we must build the data packet with the new values buffer
if valuesCap != cap(paramValues) {
data = append(data[:pos], paramValues...)
mc.buf.buf = data
}