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-rw-r--r--Godeps/_workspace/src/github.com/lib/pq/conn.go1777
1 files changed, 0 insertions, 1777 deletions
diff --git a/Godeps/_workspace/src/github.com/lib/pq/conn.go b/Godeps/_workspace/src/github.com/lib/pq/conn.go
deleted file mode 100644
index 4af880fb5..000000000
--- a/Godeps/_workspace/src/github.com/lib/pq/conn.go
+++ /dev/null
@@ -1,1777 +0,0 @@
-package pq
-
-import (
- "bufio"
- "crypto/md5"
- "crypto/tls"
- "crypto/x509"
- "database/sql"
- "database/sql/driver"
- "encoding/binary"
- "errors"
- "fmt"
- "io"
- "io/ioutil"
- "net"
- "os"
- "os/user"
- "path"
- "path/filepath"
- "strconv"
- "strings"
- "time"
- "unicode"
-
- "github.com/lib/pq/oid"
-)
-
-// Common error types
-var (
- ErrNotSupported = errors.New("pq: Unsupported command")
- ErrInFailedTransaction = errors.New("pq: Could not complete operation in a failed transaction")
- ErrSSLNotSupported = errors.New("pq: SSL is not enabled on the server")
- ErrSSLKeyHasWorldPermissions = errors.New("pq: Private key file has group or world access. Permissions should be u=rw (0600) or less.")
- ErrCouldNotDetectUsername = errors.New("pq: Could not detect default username. Please provide one explicitly.")
-)
-
-type drv struct{}
-
-func (d *drv) Open(name string) (driver.Conn, error) {
- return Open(name)
-}
-
-func init() {
- sql.Register("postgres", &drv{})
-}
-
-type parameterStatus struct {
- // server version in the same format as server_version_num, or 0 if
- // unavailable
- serverVersion int
-
- // the current location based on the TimeZone value of the session, if
- // available
- currentLocation *time.Location
-}
-
-type transactionStatus byte
-
-const (
- txnStatusIdle transactionStatus = 'I'
- txnStatusIdleInTransaction transactionStatus = 'T'
- txnStatusInFailedTransaction transactionStatus = 'E'
-)
-
-func (s transactionStatus) String() string {
- switch s {
- case txnStatusIdle:
- return "idle"
- case txnStatusIdleInTransaction:
- return "idle in transaction"
- case txnStatusInFailedTransaction:
- return "in a failed transaction"
- default:
- errorf("unknown transactionStatus %d", s)
- }
-
- panic("not reached")
-}
-
-type Dialer interface {
- Dial(network, address string) (net.Conn, error)
- DialTimeout(network, address string, timeout time.Duration) (net.Conn, error)
-}
-
-type defaultDialer struct{}
-
-func (d defaultDialer) Dial(ntw, addr string) (net.Conn, error) {
- return net.Dial(ntw, addr)
-}
-func (d defaultDialer) DialTimeout(ntw, addr string, timeout time.Duration) (net.Conn, error) {
- return net.DialTimeout(ntw, addr, timeout)
-}
-
-type conn struct {
- c net.Conn
- buf *bufio.Reader
- namei int
- scratch [512]byte
- txnStatus transactionStatus
-
- parameterStatus parameterStatus
-
- saveMessageType byte
- saveMessageBuffer []byte
-
- // If true, this connection is bad and all public-facing functions should
- // return ErrBadConn.
- bad bool
-
- // If set, this connection should never use the binary format when
- // receiving query results from prepared statements. Only provided for
- // debugging.
- disablePreparedBinaryResult bool
-
- // Whether to always send []byte parameters over as binary. Enables single
- // round-trip mode for non-prepared Query calls.
- binaryParameters bool
-}
-
-// Handle driver-side settings in parsed connection string.
-func (c *conn) handleDriverSettings(o values) (err error) {
- boolSetting := func(key string, val *bool) error {
- if value := o.Get(key); value != "" {
- if value == "yes" {
- *val = true
- } else if value == "no" {
- *val = false
- } else {
- return fmt.Errorf("unrecognized value %q for %s", value, key)
- }
- }
- return nil
- }
-
- err = boolSetting("disable_prepared_binary_result", &c.disablePreparedBinaryResult)
- if err != nil {
- return err
- }
- err = boolSetting("binary_parameters", &c.binaryParameters)
- if err != nil {
- return err
- }
- return nil
-}
-
-func (c *conn) writeBuf(b byte) *writeBuf {
- c.scratch[0] = b
- return &writeBuf{
- buf: c.scratch[:5],
- pos: 1,
- }
-}
-
-func Open(name string) (_ driver.Conn, err error) {
- return DialOpen(defaultDialer{}, name)
-}
-
-func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
- // Handle any panics during connection initialization. Note that we
- // specifically do *not* want to use errRecover(), as that would turn any
- // connection errors into ErrBadConns, hiding the real error message from
- // the user.
- defer errRecoverNoErrBadConn(&err)
-
- o := make(values)
-
- // A number of defaults are applied here, in this order:
- //
- // * Very low precedence defaults applied in every situation
- // * Environment variables
- // * Explicitly passed connection information
- o.Set("host", "localhost")
- o.Set("port", "5432")
- // N.B.: Extra float digits should be set to 3, but that breaks
- // Postgres 8.4 and older, where the max is 2.
- o.Set("extra_float_digits", "2")
- for k, v := range parseEnviron(os.Environ()) {
- o.Set(k, v)
- }
-
- if strings.HasPrefix(name, "postgres://") || strings.HasPrefix(name, "postgresql://") {
- name, err = ParseURL(name)
- if err != nil {
- return nil, err
- }
- }
-
- if err := parseOpts(name, o); err != nil {
- return nil, err
- }
-
- // Use the "fallback" application name if necessary
- if fallback := o.Get("fallback_application_name"); fallback != "" {
- if !o.Isset("application_name") {
- o.Set("application_name", fallback)
- }
- }
-
- // We can't work with any client_encoding other than UTF-8 currently.
- // However, we have historically allowed the user to set it to UTF-8
- // explicitly, and there's no reason to break such programs, so allow that.
- // Note that the "options" setting could also set client_encoding, but
- // parsing its value is not worth it. Instead, we always explicitly send
- // client_encoding as a separate run-time parameter, which should override
- // anything set in options.
- if enc := o.Get("client_encoding"); enc != "" && !isUTF8(enc) {
- return nil, errors.New("client_encoding must be absent or 'UTF8'")
- }
- o.Set("client_encoding", "UTF8")
- // DateStyle needs a similar treatment.
- if datestyle := o.Get("datestyle"); datestyle != "" {
- if datestyle != "ISO, MDY" {
- panic(fmt.Sprintf("setting datestyle must be absent or %v; got %v",
- "ISO, MDY", datestyle))
- }
- } else {
- o.Set("datestyle", "ISO, MDY")
- }
-
- // If a user is not provided by any other means, the last
- // resort is to use the current operating system provided user
- // name.
- if o.Get("user") == "" {
- u, err := userCurrent()
- if err != nil {
- return nil, err
- } else {
- o.Set("user", u)
- }
- }
-
- cn := &conn{}
- err = cn.handleDriverSettings(o)
- if err != nil {
- return nil, err
- }
-
- cn.c, err = dial(d, o)
- if err != nil {
- return nil, err
- }
- cn.ssl(o)
- cn.buf = bufio.NewReader(cn.c)
- cn.startup(o)
-
- // reset the deadline, in case one was set (see dial)
- if timeout := o.Get("connect_timeout"); timeout != "" && timeout != "0" {
- err = cn.c.SetDeadline(time.Time{})
- }
- return cn, err
-}
-
-func dial(d Dialer, o values) (net.Conn, error) {
- ntw, addr := network(o)
- // SSL is not necessary or supported over UNIX domain sockets
- if ntw == "unix" {
- o["sslmode"] = "disable"
- }
-
- // Zero or not specified means wait indefinitely.
- if timeout := o.Get("connect_timeout"); timeout != "" && timeout != "0" {
- seconds, err := strconv.ParseInt(timeout, 10, 0)
- if err != nil {
- return nil, fmt.Errorf("invalid value for parameter connect_timeout: %s", err)
- }
- duration := time.Duration(seconds) * time.Second
- // connect_timeout should apply to the entire connection establishment
- // procedure, so we both use a timeout for the TCP connection
- // establishment and set a deadline for doing the initial handshake.
- // The deadline is then reset after startup() is done.
- deadline := time.Now().Add(duration)
- conn, err := d.DialTimeout(ntw, addr, duration)
- if err != nil {
- return nil, err
- }
- err = conn.SetDeadline(deadline)
- return conn, err
- }
- return d.Dial(ntw, addr)
-}
-
-func network(o values) (string, string) {
- host := o.Get("host")
-
- if strings.HasPrefix(host, "/") {
- sockPath := path.Join(host, ".s.PGSQL."+o.Get("port"))
- return "unix", sockPath
- }
-
- return "tcp", host + ":" + o.Get("port")
-}
-
-type values map[string]string
-
-func (vs values) Set(k, v string) {
- vs[k] = v
-}
-
-func (vs values) Get(k string) (v string) {
- return vs[k]
-}
-
-func (vs values) Isset(k string) bool {
- _, ok := vs[k]
- return ok
-}
-
-// scanner implements a tokenizer for libpq-style option strings.
-type scanner struct {
- s []rune
- i int
-}
-
-// newScanner returns a new scanner initialized with the option string s.
-func newScanner(s string) *scanner {
- return &scanner{[]rune(s), 0}
-}
-
-// Next returns the next rune.
-// It returns 0, false if the end of the text has been reached.
-func (s *scanner) Next() (rune, bool) {
- if s.i >= len(s.s) {
- return 0, false
- }
- r := s.s[s.i]
- s.i++
- return r, true
-}
-
-// SkipSpaces returns the next non-whitespace rune.
-// It returns 0, false if the end of the text has been reached.
-func (s *scanner) SkipSpaces() (rune, bool) {
- r, ok := s.Next()
- for unicode.IsSpace(r) && ok {
- r, ok = s.Next()
- }
- return r, ok
-}
-
-// parseOpts parses the options from name and adds them to the values.
-//
-// The parsing code is based on conninfo_parse from libpq's fe-connect.c
-func parseOpts(name string, o values) error {
- s := newScanner(name)
-
- for {
- var (
- keyRunes, valRunes []rune
- r rune
- ok bool
- )
-
- if r, ok = s.SkipSpaces(); !ok {
- break
- }
-
- // Scan the key
- for !unicode.IsSpace(r) && r != '=' {
- keyRunes = append(keyRunes, r)
- if r, ok = s.Next(); !ok {
- break
- }
- }
-
- // Skip any whitespace if we're not at the = yet
- if r != '=' {
- r, ok = s.SkipSpaces()
- }
-
- // The current character should be =
- if r != '=' || !ok {
- return fmt.Errorf(`missing "=" after %q in connection info string"`, string(keyRunes))
- }
-
- // Skip any whitespace after the =
- if r, ok = s.SkipSpaces(); !ok {
- // If we reach the end here, the last value is just an empty string as per libpq.
- o.Set(string(keyRunes), "")
- break
- }
-
- if r != '\'' {
- for !unicode.IsSpace(r) {
- if r == '\\' {
- if r, ok = s.Next(); !ok {
- return fmt.Errorf(`missing character after backslash`)
- }
- }
- valRunes = append(valRunes, r)
-
- if r, ok = s.Next(); !ok {
- break
- }
- }
- } else {
- quote:
- for {
- if r, ok = s.Next(); !ok {
- return fmt.Errorf(`unterminated quoted string literal in connection string`)
- }
- switch r {
- case '\'':
- break quote
- case '\\':
- r, _ = s.Next()
- fallthrough
- default:
- valRunes = append(valRunes, r)
- }
- }
- }
-
- o.Set(string(keyRunes), string(valRunes))
- }
-
- return nil
-}
-
-func (cn *conn) isInTransaction() bool {
- return cn.txnStatus == txnStatusIdleInTransaction ||
- cn.txnStatus == txnStatusInFailedTransaction
-}
-
-func (cn *conn) checkIsInTransaction(intxn bool) {
- if cn.isInTransaction() != intxn {
- cn.bad = true
- errorf("unexpected transaction status %v", cn.txnStatus)
- }
-}
-
-func (cn *conn) Begin() (_ driver.Tx, err error) {
- if cn.bad {
- return nil, driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- cn.checkIsInTransaction(false)
- _, commandTag, err := cn.simpleExec("BEGIN")
- if err != nil {
- return nil, err
- }
- if commandTag != "BEGIN" {
- cn.bad = true
- return nil, fmt.Errorf("unexpected command tag %s", commandTag)
- }
- if cn.txnStatus != txnStatusIdleInTransaction {
- cn.bad = true
- return nil, fmt.Errorf("unexpected transaction status %v", cn.txnStatus)
- }
- return cn, nil
-}
-
-func (cn *conn) Commit() (err error) {
- if cn.bad {
- return driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- cn.checkIsInTransaction(true)
- // We don't want the client to think that everything is okay if it tries
- // to commit a failed transaction. However, no matter what we return,
- // database/sql will release this connection back into the free connection
- // pool so we have to abort the current transaction here. Note that you
- // would get the same behaviour if you issued a COMMIT in a failed
- // transaction, so it's also the least surprising thing to do here.
- if cn.txnStatus == txnStatusInFailedTransaction {
- if err := cn.Rollback(); err != nil {
- return err
- }
- return ErrInFailedTransaction
- }
-
- _, commandTag, err := cn.simpleExec("COMMIT")
- if err != nil {
- if cn.isInTransaction() {
- cn.bad = true
- }
- return err
- }
- if commandTag != "COMMIT" {
- cn.bad = true
- return fmt.Errorf("unexpected command tag %s", commandTag)
- }
- cn.checkIsInTransaction(false)
- return nil
-}
-
-func (cn *conn) Rollback() (err error) {
- if cn.bad {
- return driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- cn.checkIsInTransaction(true)
- _, commandTag, err := cn.simpleExec("ROLLBACK")
- if err != nil {
- if cn.isInTransaction() {
- cn.bad = true
- }
- return err
- }
- if commandTag != "ROLLBACK" {
- return fmt.Errorf("unexpected command tag %s", commandTag)
- }
- cn.checkIsInTransaction(false)
- return nil
-}
-
-func (cn *conn) gname() string {
- cn.namei++
- return strconv.FormatInt(int64(cn.namei), 10)
-}
-
-func (cn *conn) simpleExec(q string) (res driver.Result, commandTag string, err error) {
- b := cn.writeBuf('Q')
- b.string(q)
- cn.send(b)
-
- for {
- t, r := cn.recv1()
- switch t {
- case 'C':
- res, commandTag = cn.parseComplete(r.string())
- case 'Z':
- cn.processReadyForQuery(r)
- // done
- return
- case 'E':
- err = parseError(r)
- case 'T', 'D', 'I':
- // ignore any results
- default:
- cn.bad = true
- errorf("unknown response for simple query: %q", t)
- }
- }
-}
-
-func (cn *conn) simpleQuery(q string) (res *rows, err error) {
- defer cn.errRecover(&err)
-
- st := &stmt{cn: cn, name: ""}
-
- b := cn.writeBuf('Q')
- b.string(q)
- cn.send(b)
-
- for {
- t, r := cn.recv1()
- switch t {
- case 'C', 'I':
- // We allow queries which don't return any results through Query as
- // well as Exec. We still have to give database/sql a rows object
- // the user can close, though, to avoid connections from being
- // leaked. A "rows" with done=true works fine for that purpose.
- if err != nil {
- cn.bad = true
- errorf("unexpected message %q in simple query execution", t)
- }
- if res == nil {
- res = &rows{
- cn: cn,
- colNames: st.colNames,
- colTyps: st.colTyps,
- colFmts: st.colFmts,
- }
- }
- res.done = true
- case 'Z':
- cn.processReadyForQuery(r)
- // done
- return
- case 'E':
- res = nil
- err = parseError(r)
- case 'D':
- if res == nil {
- cn.bad = true
- errorf("unexpected DataRow in simple query execution")
- }
- // the query didn't fail; kick off to Next
- cn.saveMessage(t, r)
- return
- case 'T':
- // res might be non-nil here if we received a previous
- // CommandComplete, but that's fine; just overwrite it
- res = &rows{cn: cn}
- res.colNames, res.colFmts, res.colTyps = parsePortalRowDescribe(r)
-
- // To work around a bug in QueryRow in Go 1.2 and earlier, wait
- // until the first DataRow has been received.
- default:
- cn.bad = true
- errorf("unknown response for simple query: %q", t)
- }
- }
-}
-
-// Decides which column formats to use for a prepared statement. The input is
-// an array of type oids, one element per result column.
-func decideColumnFormats(colTyps []oid.Oid, forceText bool) (colFmts []format, colFmtData []byte) {
- if len(colTyps) == 0 {
- return nil, colFmtDataAllText
- }
-
- colFmts = make([]format, len(colTyps))
- if forceText {
- return colFmts, colFmtDataAllText
- }
-
- allBinary := true
- allText := true
- for i, o := range colTyps {
- switch o {
- // This is the list of types to use binary mode for when receiving them
- // through a prepared statement. If a type appears in this list, it
- // must also be implemented in binaryDecode in encode.go.
- case oid.T_bytea:
- fallthrough
- case oid.T_int8:
- fallthrough
- case oid.T_int4:
- fallthrough
- case oid.T_int2:
- colFmts[i] = formatBinary
- allText = false
-
- default:
- allBinary = false
- }
- }
-
- if allBinary {
- return colFmts, colFmtDataAllBinary
- } else if allText {
- return colFmts, colFmtDataAllText
- } else {
- colFmtData = make([]byte, 2+len(colFmts)*2)
- binary.BigEndian.PutUint16(colFmtData, uint16(len(colFmts)))
- for i, v := range colFmts {
- binary.BigEndian.PutUint16(colFmtData[2+i*2:], uint16(v))
- }
- return colFmts, colFmtData
- }
-}
-
-func (cn *conn) prepareTo(q, stmtName string) *stmt {
- st := &stmt{cn: cn, name: stmtName}
-
- b := cn.writeBuf('P')
- b.string(st.name)
- b.string(q)
- b.int16(0)
-
- b.next('D')
- b.byte('S')
- b.string(st.name)
-
- b.next('S')
- cn.send(b)
-
- cn.readParseResponse()
- st.paramTyps, st.colNames, st.colTyps = cn.readStatementDescribeResponse()
- st.colFmts, st.colFmtData = decideColumnFormats(st.colTyps, cn.disablePreparedBinaryResult)
- cn.readReadyForQuery()
- return st
-}
-
-func (cn *conn) Prepare(q string) (_ driver.Stmt, err error) {
- if cn.bad {
- return nil, driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- if len(q) >= 4 && strings.EqualFold(q[:4], "COPY") {
- return cn.prepareCopyIn(q)
- }
- return cn.prepareTo(q, cn.gname()), nil
-}
-
-func (cn *conn) Close() (err error) {
- if cn.bad {
- return driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- // Don't go through send(); ListenerConn relies on us not scribbling on the
- // scratch buffer of this connection.
- err = cn.sendSimpleMessage('X')
- if err != nil {
- return err
- }
-
- return cn.c.Close()
-}
-
-// Implement the "Queryer" interface
-func (cn *conn) Query(query string, args []driver.Value) (_ driver.Rows, err error) {
- if cn.bad {
- return nil, driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- // Check to see if we can use the "simpleQuery" interface, which is
- // *much* faster than going through prepare/exec
- if len(args) == 0 {
- return cn.simpleQuery(query)
- }
-
- if cn.binaryParameters {
- cn.sendBinaryModeQuery(query, args)
-
- cn.readParseResponse()
- cn.readBindResponse()
- rows := &rows{cn: cn}
- rows.colNames, rows.colFmts, rows.colTyps = cn.readPortalDescribeResponse()
- cn.postExecuteWorkaround()
- return rows, nil
- } else {
- st := cn.prepareTo(query, "")
- st.exec(args)
- return &rows{
- cn: cn,
- colNames: st.colNames,
- colTyps: st.colTyps,
- colFmts: st.colFmts,
- }, nil
- }
-}
-
-// Implement the optional "Execer" interface for one-shot queries
-func (cn *conn) Exec(query string, args []driver.Value) (res driver.Result, err error) {
- if cn.bad {
- return nil, driver.ErrBadConn
- }
- defer cn.errRecover(&err)
-
- // Check to see if we can use the "simpleExec" interface, which is
- // *much* faster than going through prepare/exec
- if len(args) == 0 {
- // ignore commandTag, our caller doesn't care
- r, _, err := cn.simpleExec(query)
- return r, err
- }
-
- if cn.binaryParameters {
- cn.sendBinaryModeQuery(query, args)
-
- cn.readParseResponse()
- cn.readBindResponse()
- cn.readPortalDescribeResponse()
- cn.postExecuteWorkaround()
- res, _, err = cn.readExecuteResponse("Execute")
- return res, err
- } else {
- // Use the unnamed statement to defer planning until bind
- // time, or else value-based selectivity estimates cannot be
- // used.
- st := cn.prepareTo(query, "")
- r, err := st.Exec(args)
- if err != nil {
- panic(err)
- }
- return r, err
- }
-}
-
-func (cn *conn) send(m *writeBuf) {
- _, err := cn.c.Write(m.wrap())
- if err != nil {
- panic(err)
- }
-}
-
-func (cn *conn) sendStartupPacket(m *writeBuf) {
- // sanity check
- if m.buf[0] != 0 {
- panic("oops")
- }
-
- _, err := cn.c.Write((m.wrap())[1:])
- if err != nil {
- panic(err)
- }
-}
-
-// Send a message of type typ to the server on the other end of cn. The
-// message should have no payload. This method does not use the scratch
-// buffer.
-func (cn *conn) sendSimpleMessage(typ byte) (err error) {
- _, err = cn.c.Write([]byte{typ, '\x00', '\x00', '\x00', '\x04'})
- return err
-}
-
-// saveMessage memorizes a message and its buffer in the conn struct.
-// recvMessage will then return these values on the next call to it. This
-// method is useful in cases where you have to see what the next message is
-// going to be (e.g. to see whether it's an error or not) but you can't handle
-// the message yourself.
-func (cn *conn) saveMessage(typ byte, buf *readBuf) {
- if cn.saveMessageType != 0 {
- cn.bad = true
- errorf("unexpected saveMessageType %d", cn.saveMessageType)
- }
- cn.saveMessageType = typ
- cn.saveMessageBuffer = *buf
-}
-
-// recvMessage receives any message from the backend, or returns an error if
-// a problem occurred while reading the message.
-func (cn *conn) recvMessage(r *readBuf) (byte, error) {
- // workaround for a QueryRow bug, see exec
- if cn.saveMessageType != 0 {
- t := cn.saveMessageType
- *r = cn.saveMessageBuffer
- cn.saveMessageType = 0
- cn.saveMessageBuffer = nil
- return t, nil
- }
-
- x := cn.scratch[:5]
- _, err := io.ReadFull(cn.buf, x)
- if err != nil {
- return 0, err
- }
-
- // read the type and length of the message that follows
- t := x[0]
- n := int(binary.BigEndian.Uint32(x[1:])) - 4
- var y []byte
- if n <= len(cn.scratch) {
- y = cn.scratch[:n]
- } else {
- y = make([]byte, n)
- }
- _, err = io.ReadFull(cn.buf, y)
- if err != nil {
- return 0, err
- }
- *r = y
- return t, nil
-}
-
-// recv receives a message from the backend, but if an error happened while
-// reading the message or the received message was an ErrorResponse, it panics.
-// NoticeResponses are ignored. This function should generally be used only
-// during the startup sequence.
-func (cn *conn) recv() (t byte, r *readBuf) {
- for {
- var err error
- r = &readBuf{}
- t, err = cn.recvMessage(r)
- if err != nil {
- panic(err)
- }
-
- switch t {
- case 'E':
- panic(parseError(r))
- case 'N':
- // ignore
- default:
- return
- }
- }
-}
-
-// recv1Buf is exactly equivalent to recv1, except it uses a buffer supplied by
-// the caller to avoid an allocation.
-func (cn *conn) recv1Buf(r *readBuf) byte {
- for {
- t, err := cn.recvMessage(r)
- if err != nil {
- panic(err)
- }
-
- switch t {
- case 'A', 'N':
- // ignore
- case 'S':
- cn.processParameterStatus(r)
- default:
- return t
- }
- }
-}
-
-// recv1 receives a message from the backend, panicking if an error occurs
-// while attempting to read it. All asynchronous messages are ignored, with
-// the exception of ErrorResponse.
-func (cn *conn) recv1() (t byte, r *readBuf) {
- r = &readBuf{}
- t = cn.recv1Buf(r)
- return t, r
-}
-
-func (cn *conn) ssl(o values) {
- verifyCaOnly := false
- tlsConf := tls.Config{}
- switch mode := o.Get("sslmode"); mode {
- case "require", "":
- tlsConf.InsecureSkipVerify = true
- case "verify-ca":
- // We must skip TLS's own verification since it requires full
- // verification since Go 1.3.
- tlsConf.InsecureSkipVerify = true
- verifyCaOnly = true
- case "verify-full":
- tlsConf.ServerName = o.Get("host")
- case "disable":
- return
- default:
- errorf(`unsupported sslmode %q; only "require" (default), "verify-full", and "disable" supported`, mode)
- }
-
- cn.setupSSLClientCertificates(&tlsConf, o)
- cn.setupSSLCA(&tlsConf, o)
-
- w := cn.writeBuf(0)
- w.int32(80877103)
- cn.sendStartupPacket(w)
-
- b := cn.scratch[:1]
- _, err := io.ReadFull(cn.c, b)
- if err != nil {
- panic(err)
- }
-
- if b[0] != 'S' {
- panic(ErrSSLNotSupported)
- }
-
- client := tls.Client(cn.c, &tlsConf)
- if verifyCaOnly {
- cn.verifyCA(client, &tlsConf)
- }
- cn.c = client
-}
-
-// verifyCA carries out a TLS handshake to the server and verifies the
-// presented certificate against the effective CA, i.e. the one specified in
-// sslrootcert or the system CA if sslrootcert was not specified.
-func (cn *conn) verifyCA(client *tls.Conn, tlsConf *tls.Config) {
- err := client.Handshake()
- if err != nil {
- panic(err)
- }
- certs := client.ConnectionState().PeerCertificates
- opts := x509.VerifyOptions{
- DNSName: client.ConnectionState().ServerName,
- Intermediates: x509.NewCertPool(),
- Roots: tlsConf.RootCAs,
- }
- for i, cert := range certs {
- if i == 0 {
- continue
- }
- opts.Intermediates.AddCert(cert)
- }
- _, err = certs[0].Verify(opts)
- if err != nil {
- panic(err)
- }
-}
-
-// This function sets up SSL client certificates based on either the "sslkey"
-// and "sslcert" settings (possibly set via the environment variables PGSSLKEY
-// and PGSSLCERT, respectively), or if they aren't set, from the .postgresql
-// directory in the user's home directory. If the file paths are set
-// explicitly, the files must exist. The key file must also not be
-// world-readable, or this function will panic with
-// ErrSSLKeyHasWorldPermissions.
-func (cn *conn) setupSSLClientCertificates(tlsConf *tls.Config, o values) {
- var missingOk bool
-
- sslkey := o.Get("sslkey")
- sslcert := o.Get("sslcert")
- if sslkey != "" && sslcert != "" {
- // If the user has set an sslkey and sslcert, they *must* exist.
- missingOk = false
- } else {
- // Automatically load certificates from ~/.postgresql.
- user, err := user.Current()
- if err != nil {
- // user.Current() might fail when cross-compiling. We have to
- // ignore the error and continue without client certificates, since
- // we wouldn't know where to load them from.
- return
- }
-
- sslkey = filepath.Join(user.HomeDir, ".postgresql", "postgresql.key")
- sslcert = filepath.Join(user.HomeDir, ".postgresql", "postgresql.crt")
- missingOk = true
- }
-
- // Check that both files exist, and report the error or stop, depending on
- // which behaviour we want. Note that we don't do any more extensive
- // checks than this (such as checking that the paths aren't directories);
- // LoadX509KeyPair() will take care of the rest.
- keyfinfo, err := os.Stat(sslkey)
- if err != nil && missingOk {
- return
- } else if err != nil {
- panic(err)
- }
- _, err = os.Stat(sslcert)
- if err != nil && missingOk {
- return
- } else if err != nil {
- panic(err)
- }
-
- // If we got this far, the key file must also have the correct permissions
- kmode := keyfinfo.Mode()
- if kmode != kmode&0600 {
- panic(ErrSSLKeyHasWorldPermissions)
- }
-
- cert, err := tls.LoadX509KeyPair(sslcert, sslkey)
- if err != nil {
- panic(err)
- }
- tlsConf.Certificates = []tls.Certificate{cert}
-}
-
-// Sets up RootCAs in the TLS configuration if sslrootcert is set.
-func (cn *conn) setupSSLCA(tlsConf *tls.Config, o values) {
- if sslrootcert := o.Get("sslrootcert"); sslrootcert != "" {
- tlsConf.RootCAs = x509.NewCertPool()
-
- cert, err := ioutil.ReadFile(sslrootcert)
- if err != nil {
- panic(err)
- }
-
- ok := tlsConf.RootCAs.AppendCertsFromPEM(cert)
- if !ok {
- errorf("couldn't parse pem in sslrootcert")
- }
- }
-}
-
-// isDriverSetting returns true iff a setting is purely for configuring the
-// driver's options and should not be sent to the server in the connection
-// startup packet.
-func isDriverSetting(key string) bool {
- switch key {
- case "host", "port":
- return true
- case "password":
- return true
- case "sslmode", "sslcert", "sslkey", "sslrootcert":
- return true
- case "fallback_application_name":
- return true
- case "connect_timeout":
- return true
- case "disable_prepared_binary_result":
- return true
- case "binary_parameters":
- return true
-
- default:
- return false
- }
-}
-
-func (cn *conn) startup(o values) {
- w := cn.writeBuf(0)
- w.int32(196608)
- // Send the backend the name of the database we want to connect to, and the
- // user we want to connect as. Additionally, we send over any run-time
- // parameters potentially included in the connection string. If the server
- // doesn't recognize any of them, it will reply with an error.
- for k, v := range o {
- if isDriverSetting(k) {
- // skip options which can't be run-time parameters
- continue
- }
- // The protocol requires us to supply the database name as "database"
- // instead of "dbname".
- if k == "dbname" {
- k = "database"
- }
- w.string(k)
- w.string(v)
- }
- w.string("")
- cn.sendStartupPacket(w)
-
- for {
- t, r := cn.recv()
- switch t {
- case 'K':
- case 'S':
- cn.processParameterStatus(r)
- case 'R':
- cn.auth(r, o)
- case 'Z':
- cn.processReadyForQuery(r)
- return
- default:
- errorf("unknown response for startup: %q", t)
- }
- }
-}
-
-func (cn *conn) auth(r *readBuf, o values) {
- switch code := r.int32(); code {
- case 0:
- // OK
- case 3:
- w := cn.writeBuf('p')
- w.string(o.Get("password"))
- cn.send(w)
-
- t, r := cn.recv()
- if t != 'R' {
- errorf("unexpected password response: %q", t)
- }
-
- if r.int32() != 0 {
- errorf("unexpected authentication response: %q", t)
- }
- case 5:
- s := string(r.next(4))
- w := cn.writeBuf('p')
- w.string("md5" + md5s(md5s(o.Get("password")+o.Get("user"))+s))
- cn.send(w)
-
- t, r := cn.recv()
- if t != 'R' {
- errorf("unexpected password response: %q", t)
- }
-
- if r.int32() != 0 {
- errorf("unexpected authentication response: %q", t)
- }
- default:
- errorf("unknown authentication response: %d", code)
- }
-}
-
-type format int
-
-const formatText format = 0
-const formatBinary format = 1
-
-// One result-column format code with the value 1 (i.e. all binary).
-var colFmtDataAllBinary []byte = []byte{0, 1, 0, 1}
-
-// No result-column format codes (i.e. all text).
-var colFmtDataAllText []byte = []byte{0, 0}
-
-type stmt struct {
- cn *conn
- name string
- colNames []string
- colFmts []format
- colFmtData []byte
- colTyps []oid.Oid
- paramTyps []oid.Oid
- closed bool
-}
-
-func (st *stmt) Close() (err error) {
- if st.closed {
- return nil
- }
- if st.cn.bad {
- return driver.ErrBadConn
- }
- defer st.cn.errRecover(&err)
-
- w := st.cn.writeBuf('C')
- w.byte('S')
- w.string(st.name)
- st.cn.send(w)
-
- st.cn.send(st.cn.writeBuf('S'))
-
- t, _ := st.cn.recv1()
- if t != '3' {
- st.cn.bad = true
- errorf("unexpected close response: %q", t)
- }
- st.closed = true
-
- t, r := st.cn.recv1()
- if t != 'Z' {
- st.cn.bad = true
- errorf("expected ready for query, but got: %q", t)
- }
- st.cn.processReadyForQuery(r)
-
- return nil
-}
-
-func (st *stmt) Query(v []driver.Value) (r driver.Rows, err error) {
- if st.cn.bad {
- return nil, driver.ErrBadConn
- }
- defer st.cn.errRecover(&err)
-
- st.exec(v)
- return &rows{
- cn: st.cn,
- colNames: st.colNames,
- colTyps: st.colTyps,
- colFmts: st.colFmts,
- }, nil
-}
-
-func (st *stmt) Exec(v []driver.Value) (res driver.Result, err error) {
- if st.cn.bad {
- return nil, driver.ErrBadConn
- }
- defer st.cn.errRecover(&err)
-
- st.exec(v)
- res, _, err = st.cn.readExecuteResponse("simple query")
- return res, err
-}
-
-func (st *stmt) exec(v []driver.Value) {
- if len(v) >= 65536 {
- errorf("got %d parameters but PostgreSQL only supports 65535 parameters", len(v))
- }
- if len(v) != len(st.paramTyps) {
- errorf("got %d parameters but the statement requires %d", len(v), len(st.paramTyps))
- }
-
- cn := st.cn
- w := cn.writeBuf('B')
- w.byte(0) // unnamed portal
- w.string(st.name)
-
- if cn.binaryParameters {
- cn.sendBinaryParameters(w, v)
- } else {
- w.int16(0)
- w.int16(len(v))
- for i, x := range v {
- if x == nil {
- w.int32(-1)
- } else {
- b := encode(&cn.parameterStatus, x, st.paramTyps[i])
- w.int32(len(b))
- w.bytes(b)
- }
- }
- }
- w.bytes(st.colFmtData)
-
- w.next('E')
- w.byte(0)
- w.int32(0)
-
- w.next('S')
- cn.send(w)
-
- cn.readBindResponse()
- cn.postExecuteWorkaround()
-
-}
-
-func (st *stmt) NumInput() int {
- return len(st.paramTyps)
-}
-
-// parseComplete parses the "command tag" from a CommandComplete message, and
-// returns the number of rows affected (if applicable) and a string
-// identifying only the command that was executed, e.g. "ALTER TABLE". If the
-// command tag could not be parsed, parseComplete panics.
-func (cn *conn) parseComplete(commandTag string) (driver.Result, string) {
- commandsWithAffectedRows := []string{
- "SELECT ",
- // INSERT is handled below
- "UPDATE ",
- "DELETE ",
- "FETCH ",
- "MOVE ",
- "COPY ",
- }
-
- var affectedRows *string
- for _, tag := range commandsWithAffectedRows {
- if strings.HasPrefix(commandTag, tag) {
- t := commandTag[len(tag):]
- affectedRows = &t
- commandTag = tag[:len(tag)-1]
- break
- }
- }
- // INSERT also includes the oid of the inserted row in its command tag.
- // Oids in user tables are deprecated, and the oid is only returned when
- // exactly one row is inserted, so it's unlikely to be of value to any
- // real-world application and we can ignore it.
- if affectedRows == nil && strings.HasPrefix(commandTag, "INSERT ") {
- parts := strings.Split(commandTag, " ")
- if len(parts) != 3 {
- cn.bad = true
- errorf("unexpected INSERT command tag %s", commandTag)
- }
- affectedRows = &parts[len(parts)-1]
- commandTag = "INSERT"
- }
- // There should be no affected rows attached to the tag, just return it
- if affectedRows == nil {
- return driver.RowsAffected(0), commandTag
- }
- n, err := strconv.ParseInt(*affectedRows, 10, 64)
- if err != nil {
- cn.bad = true
- errorf("could not parse commandTag: %s", err)
- }
- return driver.RowsAffected(n), commandTag
-}
-
-type rows struct {
- cn *conn
- colNames []string
- colTyps []oid.Oid
- colFmts []format
- done bool
- rb readBuf
-}
-
-func (rs *rows) Close() error {
- // no need to look at cn.bad as Next() will
- for {
- err := rs.Next(nil)
- switch err {
- case nil:
- case io.EOF:
- return nil
- default:
- return err
- }
- }
-}
-
-func (rs *rows) Columns() []string {
- return rs.colNames
-}
-
-func (rs *rows) Next(dest []driver.Value) (err error) {
- if rs.done {
- return io.EOF
- }
-
- conn := rs.cn
- if conn.bad {
- return driver.ErrBadConn
- }
- defer conn.errRecover(&err)
-
- for {
- t := conn.recv1Buf(&rs.rb)
- switch t {
- case 'E':
- err = parseError(&rs.rb)
- case 'C', 'I':
- continue
- case 'Z':
- conn.processReadyForQuery(&rs.rb)
- rs.done = true
- if err != nil {
- return err
- }
- return io.EOF
- case 'D':
- n := rs.rb.int16()
- if err != nil {
- conn.bad = true
- errorf("unexpected DataRow after error %s", err)
- }
- if n < len(dest) {
- dest = dest[:n]
- }
- for i := range dest {
- l := rs.rb.int32()
- if l == -1 {
- dest[i] = nil
- continue
- }
- dest[i] = decode(&conn.parameterStatus, rs.rb.next(l), rs.colTyps[i], rs.colFmts[i])
- }
- return
- default:
- errorf("unexpected message after execute: %q", t)
- }
- }
-}
-
-// QuoteIdentifier quotes an "identifier" (e.g. a table or a column name) to be
-// used as part of an SQL statement. For example:
-//
-// tblname := "my_table"
-// data := "my_data"
-// err = db.Exec(fmt.Sprintf("INSERT INTO %s VALUES ($1)", pq.QuoteIdentifier(tblname)), data)
-//
-// Any double quotes in name will be escaped. The quoted identifier will be
-// case sensitive when used in a query. If the input string contains a zero
-// byte, the result will be truncated immediately before it.
-func QuoteIdentifier(name string) string {
- end := strings.IndexRune(name, 0)
- if end > -1 {
- name = name[:end]
- }
- return `"` + strings.Replace(name, `"`, `""`, -1) + `"`
-}
-
-func md5s(s string) string {
- h := md5.New()
- h.Write([]byte(s))
- return fmt.Sprintf("%x", h.Sum(nil))
-}
-
-func (cn *conn) sendBinaryParameters(b *writeBuf, args []driver.Value) {
- // Do one pass over the parameters to see if we're going to send any of
- // them over in binary. If we are, create a paramFormats array at the
- // same time.
- var paramFormats []int
- for i, x := range args {
- _, ok := x.([]byte)
- if ok {
- if paramFormats == nil {
- paramFormats = make([]int, len(args))
- }
- paramFormats[i] = 1
- }
- }
- if paramFormats == nil {
- b.int16(0)
- } else {
- b.int16(len(paramFormats))
- for _, x := range paramFormats {
- b.int16(x)
- }
- }
-
- b.int16(len(args))
- for _, x := range args {
- if x == nil {
- b.int32(-1)
- } else {
- datum := binaryEncode(&cn.parameterStatus, x)
- b.int32(len(datum))
- b.bytes(datum)
- }
- }
-}
-
-func (cn *conn) sendBinaryModeQuery(query string, args []driver.Value) {
- if len(args) >= 65536 {
- errorf("got %d parameters but PostgreSQL only supports 65535 parameters", len(args))
- }
-
- b := cn.writeBuf('P')
- b.byte(0) // unnamed statement
- b.string(query)
- b.int16(0)
-
- b.next('B')
- b.int16(0) // unnamed portal and statement
- cn.sendBinaryParameters(b, args)
- b.bytes(colFmtDataAllText)
-
- b.next('D')
- b.byte('P')
- b.byte(0) // unnamed portal
-
- b.next('E')
- b.byte(0)
- b.int32(0)
-
- b.next('S')
- cn.send(b)
-}
-
-func (c *conn) processParameterStatus(r *readBuf) {
- var err error
-
- param := r.string()
- switch param {
- case "server_version":
- var major1 int
- var major2 int
- var minor int
- _, err = fmt.Sscanf(r.string(), "%d.%d.%d", &major1, &major2, &minor)
- if err == nil {
- c.parameterStatus.serverVersion = major1*10000 + major2*100 + minor
- }
-
- case "TimeZone":
- c.parameterStatus.currentLocation, err = time.LoadLocation(r.string())
- if err != nil {
- c.parameterStatus.currentLocation = nil
- }
-
- default:
- // ignore
- }
-}
-
-func (c *conn) processReadyForQuery(r *readBuf) {
- c.txnStatus = transactionStatus(r.byte())
-}
-
-func (cn *conn) readReadyForQuery() {
- t, r := cn.recv1()
- switch t {
- case 'Z':
- cn.processReadyForQuery(r)
- return
- default:
- cn.bad = true
- errorf("unexpected message %q; expected ReadyForQuery", t)
- }
-}
-
-func (cn *conn) readParseResponse() {
- t, r := cn.recv1()
- switch t {
- case '1':
- return
- case 'E':
- err := parseError(r)
- cn.readReadyForQuery()
- panic(err)
- default:
- cn.bad = true
- errorf("unexpected Parse response %q", t)
- }
-}
-
-func (cn *conn) readStatementDescribeResponse() (paramTyps []oid.Oid, colNames []string, colTyps []oid.Oid) {
- for {
- t, r := cn.recv1()
- switch t {
- case 't':
- nparams := r.int16()
- paramTyps = make([]oid.Oid, nparams)
- for i := range paramTyps {
- paramTyps[i] = r.oid()
- }
- case 'n':
- return paramTyps, nil, nil
- case 'T':
- colNames, colTyps = parseStatementRowDescribe(r)
- return paramTyps, colNames, colTyps
- case 'E':
- err := parseError(r)
- cn.readReadyForQuery()
- panic(err)
- default:
- cn.bad = true
- errorf("unexpected Describe statement response %q", t)
- }
- }
-}
-
-func (cn *conn) readPortalDescribeResponse() (colNames []string, colFmts []format, colTyps []oid.Oid) {
- t, r := cn.recv1()
- switch t {
- case 'T':
- return parsePortalRowDescribe(r)
- case 'n':
- return nil, nil, nil
- case 'E':
- err := parseError(r)
- cn.readReadyForQuery()
- panic(err)
- default:
- cn.bad = true
- errorf("unexpected Describe response %q", t)
- }
- panic("not reached")
-}
-
-func (cn *conn) readBindResponse() {
- t, r := cn.recv1()
- switch t {
- case '2':
- return
- case 'E':
- err := parseError(r)
- cn.readReadyForQuery()
- panic(err)
- default:
- cn.bad = true
- errorf("unexpected Bind response %q", t)
- }
-}
-
-func (cn *conn) postExecuteWorkaround() {
- // Work around a bug in sql.DB.QueryRow: in Go 1.2 and earlier it ignores
- // any errors from rows.Next, which masks errors that happened during the
- // execution of the query. To avoid the problem in common cases, we wait
- // here for one more message from the database. If it's not an error the
- // query will likely succeed (or perhaps has already, if it's a
- // CommandComplete), so we push the message into the conn struct; recv1
- // will return it as the next message for rows.Next or rows.Close.
- // However, if it's an error, we wait until ReadyForQuery and then return
- // the error to our caller.
- for {
- t, r := cn.recv1()
- switch t {
- case 'E':
- err := parseError(r)
- cn.readReadyForQuery()
- panic(err)
- case 'C', 'D', 'I':
- // the query didn't fail, but we can't process this message
- cn.saveMessage(t, r)
- return
- default:
- cn.bad = true
- errorf("unexpected message during extended query execution: %q", t)
- }
- }
-}
-
-// Only for Exec(), since we ignore the returned data
-func (cn *conn) readExecuteResponse(protocolState string) (res driver.Result, commandTag string, err error) {
- for {
- t, r := cn.recv1()
- switch t {
- case 'C':
- if err != nil {
- cn.bad = true
- errorf("unexpected CommandComplete after error %s", err)
- }
- res, commandTag = cn.parseComplete(r.string())
- case 'Z':
- cn.processReadyForQuery(r)
- return res, commandTag, err
- case 'E':
- err = parseError(r)
- case 'T', 'D', 'I':
- if err != nil {
- cn.bad = true
- errorf("unexpected %q after error %s", t, err)
- }
- // ignore any results
- default:
- cn.bad = true
- errorf("unknown %s response: %q", protocolState, t)
- }
- }
-}
-
-func parseStatementRowDescribe(r *readBuf) (colNames []string, colTyps []oid.Oid) {
- n := r.int16()
- colNames = make([]string, n)
- colTyps = make([]oid.Oid, n)
- for i := range colNames {
- colNames[i] = r.string()
- r.next(6)
- colTyps[i] = r.oid()
- r.next(6)
- // format code not known when describing a statement; always 0
- r.next(2)
- }
- return
-}
-
-func parsePortalRowDescribe(r *readBuf) (colNames []string, colFmts []format, colTyps []oid.Oid) {
- n := r.int16()
- colNames = make([]string, n)
- colFmts = make([]format, n)
- colTyps = make([]oid.Oid, n)
- for i := range colNames {
- colNames[i] = r.string()
- r.next(6)
- colTyps[i] = r.oid()
- r.next(6)
- colFmts[i] = format(r.int16())
- }
- return
-}
-
-// parseEnviron tries to mimic some of libpq's environment handling
-//
-// To ease testing, it does not directly reference os.Environ, but is
-// designed to accept its output.
-//
-// Environment-set connection information is intended to have a higher
-// precedence than a library default but lower than any explicitly
-// passed information (such as in the URL or connection string).
-func parseEnviron(env []string) (out map[string]string) {
- out = make(map[string]string)
-
- for _, v := range env {
- parts := strings.SplitN(v, "=", 2)
-
- accrue := func(keyname string) {
- out[keyname] = parts[1]
- }
- unsupported := func() {
- panic(fmt.Sprintf("setting %v not supported", parts[0]))
- }
-
- // The order of these is the same as is seen in the
- // PostgreSQL 9.1 manual. Unsupported but well-defined
- // keys cause a panic; these should be unset prior to
- // execution. Options which pq expects to be set to a
- // certain value are allowed, but must be set to that
- // value if present (they can, of course, be absent).
- switch parts[0] {
- case "PGHOST":
- accrue("host")
- case "PGHOSTADDR":
- unsupported()
- case "PGPORT":
- accrue("port")
- case "PGDATABASE":
- accrue("dbname")
- case "PGUSER":
- accrue("user")
- case "PGPASSWORD":
- accrue("password")
- case "PGPASSFILE", "PGSERVICE", "PGSERVICEFILE", "PGREALM":
- unsupported()
- case "PGOPTIONS":
- accrue("options")
- case "PGAPPNAME":
- accrue("application_name")
- case "PGSSLMODE":
- accrue("sslmode")
- case "PGSSLCERT":
- accrue("sslcert")
- case "PGSSLKEY":
- accrue("sslkey")
- case "PGSSLROOTCERT":
- accrue("sslrootcert")
- case "PGREQUIRESSL", "PGSSLCRL":
- unsupported()
- case "PGREQUIREPEER":
- unsupported()
- case "PGKRBSRVNAME", "PGGSSLIB":
- unsupported()
- case "PGCONNECT_TIMEOUT":
- accrue("connect_timeout")
- case "PGCLIENTENCODING":
- accrue("client_encoding")
- case "PGDATESTYLE":
- accrue("datestyle")
- case "PGTZ":
- accrue("timezone")
- case "PGGEQO":
- accrue("geqo")
- case "PGSYSCONFDIR", "PGLOCALEDIR":
- unsupported()
- }
- }
-
- return out
-}
-
-// isUTF8 returns whether name is a fuzzy variation of the string "UTF-8".
-func isUTF8(name string) bool {
- // Recognize all sorts of silly things as "UTF-8", like Postgres does
- s := strings.Map(alnumLowerASCII, name)
- return s == "utf8" || s == "unicode"
-}
-
-func alnumLowerASCII(ch rune) rune {
- if 'A' <= ch && ch <= 'Z' {
- return ch + ('a' - 'A')
- }
- if 'a' <= ch && ch <= 'z' || '0' <= ch && ch <= '9' {
- return ch
- }
- return -1 // discard
-}