824 lines
20 KiB
Go
Vendored
824 lines
20 KiB
Go
Vendored
package mssql
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import (
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"context"
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"encoding/binary"
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"errors"
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"fmt"
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"io"
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"net"
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"strconv"
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"strings"
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)
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//go:generate stringer -type token
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type token byte
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// token ids
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const (
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tokenReturnStatus token = 121 // 0x79
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tokenColMetadata token = 129 // 0x81
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tokenOrder token = 169 // 0xA9
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tokenError token = 170 // 0xAA
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tokenInfo token = 171 // 0xAB
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tokenReturnValue token = 0xAC
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tokenLoginAck token = 173 // 0xad
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tokenFeatureExtAck token = 174 // 0xae
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tokenRow token = 209 // 0xd1
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tokenNbcRow token = 210 // 0xd2
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tokenEnvChange token = 227 // 0xE3
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tokenSSPI token = 237 // 0xED
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tokenDone token = 253 // 0xFD
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tokenDoneProc token = 254
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tokenDoneInProc token = 255
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)
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// done flags
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// https://msdn.microsoft.com/en-us/library/dd340421.aspx
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const (
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doneFinal = 0
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doneMore = 1
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doneError = 2
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doneInxact = 4
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doneCount = 0x10
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doneAttn = 0x20
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doneSrvError = 0x100
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)
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// ENVCHANGE types
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// http://msdn.microsoft.com/en-us/library/dd303449.aspx
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const (
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envTypDatabase = 1
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envTypLanguage = 2
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envTypCharset = 3
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envTypPacketSize = 4
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envSortId = 5
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envSortFlags = 6
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envSqlCollation = 7
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envTypBeginTran = 8
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envTypCommitTran = 9
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envTypRollbackTran = 10
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envEnlistDTC = 11
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envDefectTran = 12
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envDatabaseMirrorPartner = 13
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envPromoteTran = 15
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envTranMgrAddr = 16
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envTranEnded = 17
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envResetConnAck = 18
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envStartedInstanceName = 19
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envRouting = 20
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)
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// COLMETADATA flags
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// https://msdn.microsoft.com/en-us/library/dd357363.aspx
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const (
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colFlagNullable = 1
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// TODO implement more flags
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)
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// interface for all tokens
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type tokenStruct interface{}
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type orderStruct struct {
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ColIds []uint16
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}
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type doneStruct struct {
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Status uint16
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CurCmd uint16
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RowCount uint64
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errors []Error
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}
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func (d doneStruct) isError() bool {
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return d.Status&doneError != 0 || len(d.errors) > 0
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}
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func (d doneStruct) getError() Error {
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if len(d.errors) > 0 {
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return d.errors[len(d.errors)-1]
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} else {
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return Error{Message: "Request failed but didn't provide reason"}
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}
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}
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type doneInProcStruct doneStruct
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var doneFlags2str = map[uint16]string{
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doneFinal: "final",
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doneMore: "more",
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doneError: "error",
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doneInxact: "inxact",
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doneCount: "count",
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doneAttn: "attn",
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doneSrvError: "srverror",
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}
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func doneFlags2Str(flags uint16) string {
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strs := make([]string, 0, len(doneFlags2str))
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for flag, tag := range doneFlags2str {
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if flags&flag != 0 {
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strs = append(strs, tag)
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}
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}
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return strings.Join(strs, "|")
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}
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// ENVCHANGE stream
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// http://msdn.microsoft.com/en-us/library/dd303449.aspx
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func processEnvChg(sess *tdsSession) {
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size := sess.buf.uint16()
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r := &io.LimitedReader{R: sess.buf, N: int64(size)}
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for {
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var err error
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var envtype uint8
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err = binary.Read(r, binary.LittleEndian, &envtype)
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if err == io.EOF {
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return
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}
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if err != nil {
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badStreamPanic(err)
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}
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switch envtype {
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case envTypDatabase:
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sess.database, err = readBVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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_, err = readBVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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case envTypLanguage:
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// currently ignored
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// new value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// old value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envTypCharset:
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// currently ignored
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// new value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// old value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envTypPacketSize:
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packetsize, err := readBVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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_, err = readBVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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packetsizei, err := strconv.Atoi(packetsize)
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if err != nil {
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badStreamPanicf("Invalid Packet size value returned from server (%s): %s", packetsize, err.Error())
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}
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sess.buf.ResizeBuffer(packetsizei)
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case envSortId:
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// currently ignored
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// new value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envSortFlags:
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// currently ignored
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// new value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envSqlCollation:
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// currently ignored
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var collationSize uint8
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err = binary.Read(r, binary.LittleEndian, &collationSize)
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if err != nil {
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badStreamPanic(err)
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}
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// SQL Collation data should contain 5 bytes in length
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if collationSize != 5 {
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badStreamPanicf("Invalid SQL Collation size value returned from server: %d", collationSize)
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}
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// 4 bytes, contains: LCID ColFlags Version
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var info uint32
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err = binary.Read(r, binary.LittleEndian, &info)
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if err != nil {
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badStreamPanic(err)
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}
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// 1 byte, contains: sortID
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var sortID uint8
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err = binary.Read(r, binary.LittleEndian, &sortID)
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if err != nil {
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badStreamPanic(err)
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}
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envTypBeginTran:
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tranid, err := readBVarByte(r)
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if len(tranid) != 8 {
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badStreamPanicf("invalid size of transaction identifier: %d", len(tranid))
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}
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sess.tranid = binary.LittleEndian.Uint64(tranid)
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if err != nil {
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badStreamPanic(err)
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}
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if sess.logFlags&logTransaction != 0 {
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sess.log.Printf("BEGIN TRANSACTION %x\n", sess.tranid)
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}
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_, err = readBVarByte(r)
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if err != nil {
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badStreamPanic(err)
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}
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case envTypCommitTran, envTypRollbackTran:
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_, err = readBVarByte(r)
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if err != nil {
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badStreamPanic(err)
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}
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_, err = readBVarByte(r)
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if err != nil {
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badStreamPanic(err)
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}
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if sess.logFlags&logTransaction != 0 {
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if envtype == envTypCommitTran {
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sess.log.Printf("COMMIT TRANSACTION %x\n", sess.tranid)
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} else {
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sess.log.Printf("ROLLBACK TRANSACTION %x\n", sess.tranid)
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}
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}
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sess.tranid = 0
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case envEnlistDTC:
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// currently ignored
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// new value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// old value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envDefectTran:
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// currently ignored
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// new value
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envDatabaseMirrorPartner:
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sess.partner, err = readBVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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_, err = readBVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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case envPromoteTran:
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// currently ignored
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// dtc token
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// spec says it should be L_VARBYTE, so this code might be wrong
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envTranMgrAddr:
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// currently ignored
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// XACT_MANAGER_ADDRESS = B_VARBYTE
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envTranEnded:
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// currently ignored
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// old value, B_VARBYTE
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envResetConnAck:
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// currently ignored
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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// should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
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case envStartedInstanceName:
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// currently ignored
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// old value, should be 0
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
|
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// instance name
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if _, err = readBVarChar(r); err != nil {
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badStreamPanic(err)
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}
|
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case envRouting:
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// RoutingData message is:
|
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// ValueLength USHORT
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// Protocol (TCP = 0) BYTE
|
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// ProtocolProperty (new port) USHORT
|
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// AlternateServer US_VARCHAR
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_, err := readUshort(r)
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if err != nil {
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badStreamPanic(err)
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}
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protocol, err := readByte(r)
|
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if err != nil || protocol != 0 {
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badStreamPanic(err)
|
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}
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newPort, err := readUshort(r)
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if err != nil {
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badStreamPanic(err)
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}
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newServer, err := readUsVarChar(r)
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if err != nil {
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badStreamPanic(err)
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}
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// consume the OLDVALUE = %x00 %x00
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_, err = readUshort(r)
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if err != nil {
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badStreamPanic(err)
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}
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sess.routedServer = newServer
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sess.routedPort = newPort
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default:
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// ignore rest of records because we don't know how to skip those
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sess.log.Printf("WARN: Unknown ENVCHANGE record detected with type id = %d\n", envtype)
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break
|
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}
|
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|
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}
|
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}
|
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|
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// http://msdn.microsoft.com/en-us/library/dd358180.aspx
|
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func parseReturnStatus(r *tdsBuffer) ReturnStatus {
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return ReturnStatus(r.int32())
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}
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func parseOrder(r *tdsBuffer) (res orderStruct) {
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len := int(r.uint16())
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res.ColIds = make([]uint16, len/2)
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for i := 0; i < len/2; i++ {
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res.ColIds[i] = r.uint16()
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}
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return res
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}
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|
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// https://msdn.microsoft.com/en-us/library/dd340421.aspx
|
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func parseDone(r *tdsBuffer) (res doneStruct) {
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res.Status = r.uint16()
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res.CurCmd = r.uint16()
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res.RowCount = r.uint64()
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return res
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}
|
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|
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// https://msdn.microsoft.com/en-us/library/dd340553.aspx
|
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func parseDoneInProc(r *tdsBuffer) (res doneInProcStruct) {
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res.Status = r.uint16()
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res.CurCmd = r.uint16()
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res.RowCount = r.uint64()
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return res
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}
|
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|
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type sspiMsg []byte
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|
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func parseSSPIMsg(r *tdsBuffer) sspiMsg {
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size := r.uint16()
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buf := make([]byte, size)
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r.ReadFull(buf)
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return sspiMsg(buf)
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}
|
|
|
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type loginAckStruct struct {
|
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Interface uint8
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TDSVersion uint32
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ProgName string
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ProgVer uint32
|
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}
|
|
|
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func parseLoginAck(r *tdsBuffer) loginAckStruct {
|
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size := r.uint16()
|
|
buf := make([]byte, size)
|
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r.ReadFull(buf)
|
|
var res loginAckStruct
|
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res.Interface = buf[0]
|
|
res.TDSVersion = binary.BigEndian.Uint32(buf[1:])
|
|
prognamelen := buf[1+4]
|
|
var err error
|
|
if res.ProgName, err = ucs22str(buf[1+4+1 : 1+4+1+prognamelen*2]); err != nil {
|
|
badStreamPanic(err)
|
|
}
|
|
res.ProgVer = binary.BigEndian.Uint32(buf[size-4:])
|
|
return res
|
|
}
|
|
|
|
// https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-tds/2eb82f8e-11f0-46dc-b42d-27302fa4701a
|
|
func parseFeatureExtAck(r *tdsBuffer) {
|
|
// at most 1 featureAck per feature in featureExt
|
|
// go-mssqldb will add at most 1 feature, the spec defines 7 different features
|
|
for i := 0; i < 8; i++ {
|
|
featureID := r.byte() // FeatureID
|
|
if featureID == 0xff {
|
|
return
|
|
}
|
|
size := r.uint32() // FeatureAckDataLen
|
|
d := make([]byte, size)
|
|
r.ReadFull(d)
|
|
}
|
|
panic("parsed more than 7 featureAck's, protocol implementation error?")
|
|
}
|
|
|
|
// http://msdn.microsoft.com/en-us/library/dd357363.aspx
|
|
func parseColMetadata72(r *tdsBuffer) (columns []columnStruct) {
|
|
count := r.uint16()
|
|
if count == 0xffff {
|
|
// no metadata is sent
|
|
return nil
|
|
}
|
|
columns = make([]columnStruct, count)
|
|
for i := range columns {
|
|
column := &columns[i]
|
|
column.UserType = r.uint32()
|
|
column.Flags = r.uint16()
|
|
|
|
// parsing TYPE_INFO structure
|
|
column.ti = readTypeInfo(r)
|
|
column.ColName = r.BVarChar()
|
|
}
|
|
return columns
|
|
}
|
|
|
|
// http://msdn.microsoft.com/en-us/library/dd357254.aspx
|
|
func parseRow(r *tdsBuffer, columns []columnStruct, row []interface{}) {
|
|
for i, column := range columns {
|
|
row[i] = column.ti.Reader(&column.ti, r)
|
|
}
|
|
}
|
|
|
|
// http://msdn.microsoft.com/en-us/library/dd304783.aspx
|
|
func parseNbcRow(r *tdsBuffer, columns []columnStruct, row []interface{}) {
|
|
bitlen := (len(columns) + 7) / 8
|
|
pres := make([]byte, bitlen)
|
|
r.ReadFull(pres)
|
|
for i, col := range columns {
|
|
if pres[i/8]&(1<<(uint(i)%8)) != 0 {
|
|
row[i] = nil
|
|
continue
|
|
}
|
|
row[i] = col.ti.Reader(&col.ti, r)
|
|
}
|
|
}
|
|
|
|
// http://msdn.microsoft.com/en-us/library/dd304156.aspx
|
|
func parseError72(r *tdsBuffer) (res Error) {
|
|
length := r.uint16()
|
|
_ = length // ignore length
|
|
res.Number = r.int32()
|
|
res.State = r.byte()
|
|
res.Class = r.byte()
|
|
res.Message = r.UsVarChar()
|
|
res.ServerName = r.BVarChar()
|
|
res.ProcName = r.BVarChar()
|
|
res.LineNo = r.int32()
|
|
return
|
|
}
|
|
|
|
// http://msdn.microsoft.com/en-us/library/dd304156.aspx
|
|
func parseInfo(r *tdsBuffer) (res Error) {
|
|
length := r.uint16()
|
|
_ = length // ignore length
|
|
res.Number = r.int32()
|
|
res.State = r.byte()
|
|
res.Class = r.byte()
|
|
res.Message = r.UsVarChar()
|
|
res.ServerName = r.BVarChar()
|
|
res.ProcName = r.BVarChar()
|
|
res.LineNo = r.int32()
|
|
return
|
|
}
|
|
|
|
// https://msdn.microsoft.com/en-us/library/dd303881.aspx
|
|
func parseReturnValue(r *tdsBuffer) (nv namedValue) {
|
|
/*
|
|
ParamOrdinal
|
|
ParamName
|
|
Status
|
|
UserType
|
|
Flags
|
|
TypeInfo
|
|
CryptoMetadata
|
|
Value
|
|
*/
|
|
r.uint16()
|
|
nv.Name = r.BVarChar()
|
|
r.byte()
|
|
r.uint32() // UserType (uint16 prior to 7.2)
|
|
r.uint16()
|
|
ti := readTypeInfo(r)
|
|
nv.Value = ti.Reader(&ti, r)
|
|
return
|
|
}
|
|
|
|
func processSingleResponse(sess *tdsSession, ch chan tokenStruct, outs map[string]interface{}) {
|
|
defer func() {
|
|
if err := recover(); err != nil {
|
|
if sess.logFlags&logErrors != 0 {
|
|
sess.log.Printf("ERROR: Intercepted panic %v", err)
|
|
}
|
|
ch <- err
|
|
}
|
|
close(ch)
|
|
}()
|
|
|
|
packet_type, err := sess.buf.BeginRead()
|
|
if err != nil {
|
|
if sess.logFlags&logErrors != 0 {
|
|
sess.log.Printf("ERROR: BeginRead failed %v", err)
|
|
}
|
|
ch <- err
|
|
return
|
|
}
|
|
if packet_type != packReply {
|
|
badStreamPanic(fmt.Errorf("unexpected packet type in reply: got %v, expected %v", packet_type, packReply))
|
|
}
|
|
var columns []columnStruct
|
|
errs := make([]Error, 0, 5)
|
|
for {
|
|
token := token(sess.buf.byte())
|
|
if sess.logFlags&logDebug != 0 {
|
|
sess.log.Printf("got token %v", token)
|
|
}
|
|
switch token {
|
|
case tokenSSPI:
|
|
ch <- parseSSPIMsg(sess.buf)
|
|
return
|
|
case tokenReturnStatus:
|
|
returnStatus := parseReturnStatus(sess.buf)
|
|
ch <- returnStatus
|
|
case tokenLoginAck:
|
|
loginAck := parseLoginAck(sess.buf)
|
|
ch <- loginAck
|
|
case tokenFeatureExtAck:
|
|
parseFeatureExtAck(sess.buf)
|
|
case tokenOrder:
|
|
order := parseOrder(sess.buf)
|
|
ch <- order
|
|
case tokenDoneInProc:
|
|
done := parseDoneInProc(sess.buf)
|
|
if sess.logFlags&logRows != 0 && done.Status&doneCount != 0 {
|
|
sess.log.Printf("(%d row(s) affected)\n", done.RowCount)
|
|
}
|
|
ch <- done
|
|
case tokenDone, tokenDoneProc:
|
|
done := parseDone(sess.buf)
|
|
done.errors = errs
|
|
if sess.logFlags&logDebug != 0 {
|
|
sess.log.Printf("got DONE or DONEPROC status=%d", done.Status)
|
|
}
|
|
if done.Status&doneSrvError != 0 {
|
|
ch <- errors.New("SQL Server had internal error")
|
|
return
|
|
}
|
|
if sess.logFlags&logRows != 0 && done.Status&doneCount != 0 {
|
|
sess.log.Printf("(%d row(s) affected)\n", done.RowCount)
|
|
}
|
|
ch <- done
|
|
if done.Status&doneMore == 0 {
|
|
return
|
|
}
|
|
case tokenColMetadata:
|
|
columns = parseColMetadata72(sess.buf)
|
|
ch <- columns
|
|
case tokenRow:
|
|
row := make([]interface{}, len(columns))
|
|
parseRow(sess.buf, columns, row)
|
|
ch <- row
|
|
case tokenNbcRow:
|
|
row := make([]interface{}, len(columns))
|
|
parseNbcRow(sess.buf, columns, row)
|
|
ch <- row
|
|
case tokenEnvChange:
|
|
processEnvChg(sess)
|
|
case tokenError:
|
|
err := parseError72(sess.buf)
|
|
if sess.logFlags&logDebug != 0 {
|
|
sess.log.Printf("got ERROR %d %s", err.Number, err.Message)
|
|
}
|
|
errs = append(errs, err)
|
|
if sess.logFlags&logErrors != 0 {
|
|
sess.log.Println(err.Message)
|
|
}
|
|
case tokenInfo:
|
|
info := parseInfo(sess.buf)
|
|
if sess.logFlags&logDebug != 0 {
|
|
sess.log.Printf("got INFO %d %s", info.Number, info.Message)
|
|
}
|
|
if sess.logFlags&logMessages != 0 {
|
|
sess.log.Println(info.Message)
|
|
}
|
|
case tokenReturnValue:
|
|
nv := parseReturnValue(sess.buf)
|
|
if len(nv.Name) > 0 {
|
|
name := nv.Name[1:] // Remove the leading "@".
|
|
if ov, has := outs[name]; has {
|
|
err = scanIntoOut(name, nv.Value, ov)
|
|
if err != nil {
|
|
fmt.Println("scan error", err)
|
|
ch <- err
|
|
}
|
|
}
|
|
}
|
|
default:
|
|
badStreamPanic(fmt.Errorf("unknown token type returned: %v", token))
|
|
}
|
|
}
|
|
}
|
|
|
|
type parseRespIter byte
|
|
|
|
const (
|
|
parseRespIterContinue parseRespIter = iota // Continue parsing current token.
|
|
parseRespIterNext // Fetch the next token.
|
|
parseRespIterDone // Done with parsing the response.
|
|
)
|
|
|
|
type parseRespState byte
|
|
|
|
const (
|
|
parseRespStateNormal parseRespState = iota // Normal response state.
|
|
parseRespStateCancel // Query is canceled, wait for server to confirm.
|
|
parseRespStateClosing // Waiting for tokens to come through.
|
|
)
|
|
|
|
type parseResp struct {
|
|
sess *tdsSession
|
|
ctxDone <-chan struct{}
|
|
state parseRespState
|
|
cancelError error
|
|
}
|
|
|
|
func (ts *parseResp) sendAttention(ch chan tokenStruct) parseRespIter {
|
|
if err := sendAttention(ts.sess.buf); err != nil {
|
|
ts.dlogf("failed to send attention signal %v", err)
|
|
ch <- err
|
|
return parseRespIterDone
|
|
}
|
|
ts.state = parseRespStateCancel
|
|
return parseRespIterContinue
|
|
}
|
|
|
|
func (ts *parseResp) dlog(msg string) {
|
|
if ts.sess.logFlags&logDebug != 0 {
|
|
ts.sess.log.Println(msg)
|
|
}
|
|
}
|
|
func (ts *parseResp) dlogf(f string, v ...interface{}) {
|
|
if ts.sess.logFlags&logDebug != 0 {
|
|
ts.sess.log.Printf(f, v...)
|
|
}
|
|
}
|
|
|
|
func (ts *parseResp) iter(ctx context.Context, ch chan tokenStruct, tokChan chan tokenStruct) parseRespIter {
|
|
switch ts.state {
|
|
default:
|
|
panic("unknown state")
|
|
case parseRespStateNormal:
|
|
select {
|
|
case tok, ok := <-tokChan:
|
|
if !ok {
|
|
ts.dlog("response finished")
|
|
return parseRespIterDone
|
|
}
|
|
if err, ok := tok.(net.Error); ok && err.Timeout() {
|
|
ts.cancelError = err
|
|
ts.dlog("got timeout error, sending attention signal to server")
|
|
return ts.sendAttention(ch)
|
|
}
|
|
// Pass the token along.
|
|
ch <- tok
|
|
return parseRespIterContinue
|
|
|
|
case <-ts.ctxDone:
|
|
ts.ctxDone = nil
|
|
ts.dlog("got cancel message, sending attention signal to server")
|
|
return ts.sendAttention(ch)
|
|
}
|
|
case parseRespStateCancel: // Read all responses until a DONE or error is received.Auth
|
|
select {
|
|
case tok, ok := <-tokChan:
|
|
if !ok {
|
|
ts.dlog("response finished but waiting for attention ack")
|
|
return parseRespIterNext
|
|
}
|
|
switch tok := tok.(type) {
|
|
default:
|
|
// Ignore all other tokens while waiting.
|
|
// The TDS spec says other tokens may arrive after an attention
|
|
// signal is sent. Ignore these tokens and continue looking for
|
|
// a DONE with attention confirm mark.
|
|
case doneStruct:
|
|
if tok.Status&doneAttn != 0 {
|
|
ts.dlog("got cancellation confirmation from server")
|
|
if ts.cancelError != nil {
|
|
ch <- ts.cancelError
|
|
ts.cancelError = nil
|
|
} else {
|
|
ch <- ctx.Err()
|
|
}
|
|
return parseRespIterDone
|
|
}
|
|
|
|
// If an error happens during cancel, pass it along and just stop.
|
|
// We are uncertain to receive more tokens.
|
|
case error:
|
|
ch <- tok
|
|
ts.state = parseRespStateClosing
|
|
}
|
|
return parseRespIterContinue
|
|
case <-ts.ctxDone:
|
|
ts.ctxDone = nil
|
|
ts.state = parseRespStateClosing
|
|
return parseRespIterContinue
|
|
}
|
|
case parseRespStateClosing: // Wait for current token chan to close.
|
|
if _, ok := <-tokChan; !ok {
|
|
ts.dlog("response finished")
|
|
return parseRespIterDone
|
|
}
|
|
return parseRespIterContinue
|
|
}
|
|
}
|
|
|
|
func processResponse(ctx context.Context, sess *tdsSession, ch chan tokenStruct, outs map[string]interface{}) {
|
|
ts := &parseResp{
|
|
sess: sess,
|
|
ctxDone: ctx.Done(),
|
|
}
|
|
defer func() {
|
|
// Ensure any remaining error is piped through
|
|
// or the query may look like it executed when it actually failed.
|
|
if ts.cancelError != nil {
|
|
ch <- ts.cancelError
|
|
ts.cancelError = nil
|
|
}
|
|
close(ch)
|
|
}()
|
|
|
|
// Loop over multiple responses.
|
|
for {
|
|
ts.dlog("initiating response reading")
|
|
|
|
tokChan := make(chan tokenStruct)
|
|
go processSingleResponse(sess, tokChan, outs)
|
|
|
|
// Loop over multiple tokens in response.
|
|
tokensLoop:
|
|
for {
|
|
switch ts.iter(ctx, ch, tokChan) {
|
|
case parseRespIterContinue:
|
|
// Nothing, continue to next token.
|
|
case parseRespIterNext:
|
|
break tokensLoop
|
|
case parseRespIterDone:
|
|
return
|
|
}
|
|
}
|
|
}
|
|
}
|