diff options
Diffstat (limited to 'vendor/github.com/lib/pq/conn.go')
| -rw-r--r-- | vendor/github.com/lib/pq/conn.go | 2060 |
1 files changed, 2060 insertions, 0 deletions
diff --git a/vendor/github.com/lib/pq/conn.go b/vendor/github.com/lib/pq/conn.go new file mode 100644 index 0000000..e050d53 --- /dev/null +++ b/vendor/github.com/lib/pq/conn.go @@ -0,0 +1,2060 @@ +package pq + +import ( + "bufio" + "context" + "crypto/md5" + "crypto/sha256" + "database/sql" + "database/sql/driver" + "encoding/binary" + "errors" + "fmt" + "io" + "net" + "os" + "os/user" + "path" + "path/filepath" + "strconv" + "strings" + "sync" + "time" + "unicode" + + "github.com/lib/pq/oid" + "github.com/lib/pq/scram" +) + +// 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") + + errUnexpectedReady = errors.New("unexpected ReadyForQuery") + errNoRowsAffected = errors.New("no RowsAffected available after the empty statement") + errNoLastInsertID = errors.New("no LastInsertId available after the empty statement") +) + +// Compile time validation that our types implement the expected interfaces +var ( + _ driver.Driver = Driver{} +) + +// Driver is the Postgres database driver. +type Driver struct{} + +// Open opens a new connection to the database. name is a connection string. +// Most users should only use it through database/sql package from the standard +// library. +func (d Driver) Open(name string) (driver.Conn, error) { + return Open(name) +} + +func init() { + sql.Register("postgres", &Driver{}) +} + +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") +} + +// Dialer is the dialer interface. It can be used to obtain more control over +// how pq creates network connections. +type Dialer interface { + Dial(network, address string) (net.Conn, error) + DialTimeout(network, address string, timeout time.Duration) (net.Conn, error) +} + +// DialerContext is the context-aware dialer interface. +type DialerContext interface { + DialContext(ctx context.Context, network, address string) (net.Conn, error) +} + +type defaultDialer struct { + d net.Dialer +} + +func (d defaultDialer) Dial(network, address string) (net.Conn, error) { + return d.d.Dial(network, address) +} +func (d defaultDialer) DialTimeout(network, address string, timeout time.Duration) (net.Conn, error) { + ctx, cancel := context.WithTimeout(context.Background(), timeout) + defer cancel() + return d.DialContext(ctx, network, address) +} +func (d defaultDialer) DialContext(ctx context.Context, network, address string) (net.Conn, error) { + return d.d.DialContext(ctx, network, address) +} + +type conn struct { + c net.Conn + buf *bufio.Reader + namei int + scratch [512]byte + txnStatus transactionStatus + txnFinish func() + + // Save connection arguments to use during CancelRequest. + dialer Dialer + opts values + + // Cancellation key data for use with CancelRequest messages. + processID int + secretKey int + + parameterStatus parameterStatus + + saveMessageType byte + saveMessageBuffer []byte + + // If an error is set, this connection is bad and all public-facing + // functions should return the appropriate error by calling get() + // (ErrBadConn) or getForNext(). + err syncErr + + // 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 + + // If true this connection is in the middle of a COPY + inCopy bool + + // If not nil, notices will be synchronously sent here + noticeHandler func(*Error) + + // If not nil, notifications will be synchronously sent here + notificationHandler func(*Notification) + + // GSSAPI context + gss GSS +} + +type syncErr struct { + err error + sync.Mutex +} + +// Return ErrBadConn if connection is bad. +func (e *syncErr) get() error { + e.Lock() + defer e.Unlock() + if e.err != nil { + return driver.ErrBadConn + } + return nil +} + +// Return the error set on the connection. Currently only used by rows.Next. +func (e *syncErr) getForNext() error { + e.Lock() + defer e.Unlock() + return e.err +} + +// Set error, only if it isn't set yet. +func (e *syncErr) set(err error) { + if err == nil { + panic("attempt to set nil err") + } + e.Lock() + defer e.Unlock() + if e.err == nil { + e.err = err + } +} + +// Handle driver-side settings in parsed connection string. +func (cn *conn) handleDriverSettings(o values) (err error) { + boolSetting := func(key string, val *bool) error { + if value, ok := o[key]; ok { + 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", &cn.disablePreparedBinaryResult) + if err != nil { + return err + } + return boolSetting("binary_parameters", &cn.binaryParameters) +} + +func (cn *conn) handlePgpass(o values) { + // if a password was supplied, do not process .pgpass + if _, ok := o["password"]; ok { + return + } + filename := os.Getenv("PGPASSFILE") + if filename == "" { + // XXX this code doesn't work on Windows where the default filename is + // XXX %APPDATA%\postgresql\pgpass.conf + // Prefer $HOME over user.Current due to glibc bug: golang.org/issue/13470 + userHome := os.Getenv("HOME") + if userHome == "" { + user, err := user.Current() + if err != nil { + return + } + userHome = user.HomeDir + } + filename = filepath.Join(userHome, ".pgpass") + } + fileinfo, err := os.Stat(filename) + if err != nil { + return + } + mode := fileinfo.Mode() + if mode&(0x77) != 0 { + // XXX should warn about incorrect .pgpass permissions as psql does + return + } + file, err := os.Open(filename) + if err != nil { + return + } + defer file.Close() + scanner := bufio.NewScanner(io.Reader(file)) + hostname := o["host"] + ntw, _ := network(o) + port := o["port"] + db := o["dbname"] + username := o["user"] + // From: https://github.com/tg/pgpass/blob/master/reader.go + getFields := func(s string) []string { + fs := make([]string, 0, 5) + f := make([]rune, 0, len(s)) + + var esc bool + for _, c := range s { + switch { + case esc: + f = append(f, c) + esc = false + case c == '\\': + esc = true + case c == ':': + fs = append(fs, string(f)) + f = f[:0] + default: + f = append(f, c) + } + } + return append(fs, string(f)) + } + for scanner.Scan() { + line := scanner.Text() + if len(line) == 0 || line[0] == '#' { + continue + } + split := getFields(line) + if len(split) != 5 { + continue + } + if (split[0] == "*" || split[0] == hostname || (split[0] == "localhost" && (hostname == "" || ntw == "unix"))) && (split[1] == "*" || split[1] == port) && (split[2] == "*" || split[2] == db) && (split[3] == "*" || split[3] == username) { + o["password"] = split[4] + return + } + } +} + +func (cn *conn) writeBuf(b byte) *writeBuf { + cn.scratch[0] = b + return &writeBuf{ + buf: cn.scratch[:5], + pos: 1, + } +} + +// Open opens a new connection to the database. dsn is a connection string. +// Most users should only use it through database/sql package from the standard +// library. +func Open(dsn string) (_ driver.Conn, err error) { + return DialOpen(defaultDialer{}, dsn) +} + +// DialOpen opens a new connection to the database using a dialer. +func DialOpen(d Dialer, dsn string) (_ driver.Conn, err error) { + c, err := NewConnector(dsn) + if err != nil { + return nil, err + } + c.dialer = d + return c.open(context.Background()) +} + +func (c *Connector) open(ctx context.Context) (cn *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) + + // Create a new values map (copy). This makes it so maps in different + // connections do not reference the same underlying data structure, so it + // is safe for multiple connections to concurrently write to their opts. + o := make(values) + for k, v := range c.opts { + o[k] = v + } + + cn = &conn{ + opts: o, + dialer: c.dialer, + } + err = cn.handleDriverSettings(o) + if err != nil { + return nil, err + } + cn.handlePgpass(o) + + cn.c, err = dial(ctx, c.dialer, o) + if err != nil { + return nil, err + } + + err = cn.ssl(o) + if err != nil { + if cn.c != nil { + cn.c.Close() + } + return nil, err + } + + // cn.startup panics on error. Make sure we don't leak cn.c. + panicking := true + defer func() { + if panicking { + cn.c.Close() + } + }() + + cn.buf = bufio.NewReader(cn.c) + cn.startup(o) + + // reset the deadline, in case one was set (see dial) + if timeout, ok := o["connect_timeout"]; ok && timeout != "0" { + err = cn.c.SetDeadline(time.Time{}) + } + panicking = false + return cn, err +} + +func dial(ctx context.Context, d Dialer, o values) (net.Conn, error) { + network, address := network(o) + + // Zero or not specified means wait indefinitely. + if timeout, ok := o["connect_timeout"]; ok && 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) + var conn net.Conn + if dctx, ok := d.(DialerContext); ok { + ctx, cancel := context.WithTimeout(ctx, duration) + defer cancel() + conn, err = dctx.DialContext(ctx, network, address) + } else { + conn, err = d.DialTimeout(network, address, duration) + } + if err != nil { + return nil, err + } + err = conn.SetDeadline(deadline) + return conn, err + } + if dctx, ok := d.(DialerContext); ok { + return dctx.DialContext(ctx, network, address) + } + return d.Dial(network, address) +} + +func network(o values) (string, string) { + host := o["host"] + + if strings.HasPrefix(host, "/") { + sockPath := path.Join(host, ".s.PGSQL."+o["port"]) + return "unix", sockPath + } + + return "tcp", net.JoinHostPort(host, o["port"]) +} + +type values map[string]string + +// 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[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[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.err.set(driver.ErrBadConn) + errorf("unexpected transaction status %v", cn.txnStatus) + } +} + +func (cn *conn) Begin() (_ driver.Tx, err error) { + return cn.begin("") +} + +func (cn *conn) begin(mode string) (_ driver.Tx, err error) { + if err := cn.err.get(); err != nil { + return nil, err + } + defer cn.errRecover(&err) + + cn.checkIsInTransaction(false) + _, commandTag, err := cn.simpleExec("BEGIN" + mode) + if err != nil { + return nil, err + } + if commandTag != "BEGIN" { + cn.err.set(driver.ErrBadConn) + return nil, fmt.Errorf("unexpected command tag %s", commandTag) + } + if cn.txnStatus != txnStatusIdleInTransaction { + cn.err.set(driver.ErrBadConn) + return nil, fmt.Errorf("unexpected transaction status %v", cn.txnStatus) + } + return cn, nil +} + +func (cn *conn) closeTxn() { + if finish := cn.txnFinish; finish != nil { + finish() + } +} + +func (cn *conn) Commit() (err error) { + defer cn.closeTxn() + if err := cn.err.get(); err != nil { + return err + } + 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.err.set(driver.ErrBadConn) + } + return err + } + if commandTag != "COMMIT" { + cn.err.set(driver.ErrBadConn) + return fmt.Errorf("unexpected command tag %s", commandTag) + } + cn.checkIsInTransaction(false) + return nil +} + +func (cn *conn) Rollback() (err error) { + defer cn.closeTxn() + if err := cn.err.get(); err != nil { + return err + } + defer cn.errRecover(&err) + return cn.rollback() +} + +func (cn *conn) rollback() (err error) { + cn.checkIsInTransaction(true) + _, commandTag, err := cn.simpleExec("ROLLBACK") + if err != nil { + if cn.isInTransaction() { + cn.err.set(driver.ErrBadConn) + } + 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) + if res == nil && err == nil { + err = errUnexpectedReady + } + // done + return + case 'E': + err = parseError(r) + case 'I': + res = emptyRows + case 'T', 'D': + // ignore any results + default: + cn.err.set(driver.ErrBadConn) + errorf("unknown response for simple query: %q", t) + } + } +} + +func (cn *conn) simpleQuery(q string) (res *rows, err error) { + defer cn.errRecover(&err) + + 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.err.set(driver.ErrBadConn) + errorf("unexpected message %q in simple query execution", t) + } + if res == nil { + res = &rows{ + cn: cn, + } + } + // Set the result and tag to the last command complete if there wasn't a + // query already run. Although queries usually return from here and cede + // control to Next, a query with zero results does not. + if t == 'C' { + res.result, res.tag = cn.parseComplete(r.string()) + if res.colNames != nil { + return + } + } + res.done = true + case 'Z': + cn.processReadyForQuery(r) + // done + return + case 'E': + res = nil + err = parseError(r) + case 'D': + if res == nil { + cn.err.set(driver.ErrBadConn) + 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.rowsHeader = 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.err.set(driver.ErrBadConn) + errorf("unknown response for simple query: %q", t) + } + } +} + +type noRows struct{} + +var emptyRows noRows + +var _ driver.Result = noRows{} + +func (noRows) LastInsertId() (int64, error) { + return 0, errNoLastInsertID +} + +func (noRows) RowsAffected() (int64, error) { + return 0, errNoRowsAffected +} + +// 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 []fieldDesc, 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, t := range colTyps { + switch t.OID { + // 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: + fallthrough + case oid.T_uuid: + 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 err := cn.err.get(); err != nil { + return nil, err + } + defer cn.errRecover(&err) + + if len(q) >= 4 && strings.EqualFold(q[:4], "COPY") { + s, err := cn.prepareCopyIn(q) + if err == nil { + cn.inCopy = true + } + return s, err + } + return cn.prepareTo(q, cn.gname()), nil +} + +func (cn *conn) Close() (err error) { + // Skip cn.bad return here because we always want to close a connection. + defer cn.errRecover(&err) + + // Ensure that cn.c.Close is always run. Since error handling is done with + // panics and cn.errRecover, the Close must be in a defer. + defer func() { + cerr := cn.c.Close() + if err == nil { + err = cerr + } + }() + + // Don't go through send(); ListenerConn relies on us not scribbling on the + // scratch buffer of this connection. + return cn.sendSimpleMessage('X') +} + +// Implement the "Queryer" interface +func (cn *conn) Query(query string, args []driver.Value) (driver.Rows, error) { + return cn.query(query, args) +} + +func (cn *conn) query(query string, args []driver.Value) (_ *rows, err error) { + if err := cn.err.get(); err != nil { + return nil, err + } + if cn.inCopy { + return nil, errCopyInProgress + } + 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.rowsHeader = cn.readPortalDescribeResponse() + cn.postExecuteWorkaround() + return rows, nil + } + st := cn.prepareTo(query, "") + st.exec(args) + return &rows{ + cn: cn, + rowsHeader: st.rowsHeader, + }, 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 err := cn.err.get(); err != nil { + return nil, err + } + 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 + } + // 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 +} + +type safeRetryError struct { + Err error +} + +func (se *safeRetryError) Error() string { + return se.Err.Error() +} + +func (cn *conn) send(m *writeBuf) { + n, err := cn.c.Write(m.wrap()) + if err != nil { + if n == 0 { + err = &safeRetryError{Err: err} + } + panic(err) + } +} + +func (cn *conn) sendStartupPacket(m *writeBuf) error { + _, err := cn.c.Write((m.wrap())[1:]) + return 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.err.set(driver.ErrBadConn) + 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': + if n := cn.noticeHandler; n != nil { + n(parseError(r)) + } + case 'A': + if n := cn.notificationHandler; n != nil { + n(recvNotification(r)) + } + 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': + if n := cn.notificationHandler; n != nil { + n(recvNotification(r)) + } + case 'N': + if n := cn.noticeHandler; n != nil { + n(parseError(r)) + } + 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) error { + upgrade, err := ssl(o) + if err != nil { + return err + } + + if upgrade == nil { + // Nothing to do + return nil + } + + w := cn.writeBuf(0) + w.int32(80877103) + if err = cn.sendStartupPacket(w); err != nil { + return err + } + + b := cn.scratch[:1] + _, err = io.ReadFull(cn.c, b) + if err != nil { + return err + } + + if b[0] != 'S' { + return ErrSSLNotSupported + } + + cn.c, err = upgrade(cn.c) + return err +} + +// 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", "sslinline": + 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 + case "krbsrvname": + return true + case "krbspn": + 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("") + if err := cn.sendStartupPacket(w); err != nil { + panic(err) + } + + for { + t, r := cn.recv() + switch t { + case 'K': + cn.processBackendKeyData(r) + 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["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["password"]+o["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) + } + case 7: // GSSAPI, startup + if newGss == nil { + errorf("kerberos error: no GSSAPI provider registered (import github.com/lib/pq/auth/kerberos if you need Kerberos support)") + } + cli, err := newGss() + if err != nil { + errorf("kerberos error: %s", err.Error()) + } + + var token []byte + + if spn, ok := o["krbspn"]; ok { + // Use the supplied SPN if provided.. + token, err = cli.GetInitTokenFromSpn(spn) + } else { + // Allow the kerberos service name to be overridden + service := "postgres" + if val, ok := o["krbsrvname"]; ok { + service = val + } + + token, err = cli.GetInitToken(o["host"], service) + } + + if err != nil { + errorf("failed to get Kerberos ticket: %q", err) + } + + w := cn.writeBuf('p') + w.bytes(token) + cn.send(w) + + // Store for GSSAPI continue message + cn.gss = cli + + case 8: // GSSAPI continue + + if cn.gss == nil { + errorf("GSSAPI protocol error") + } + + b := []byte(*r) + + done, tokOut, err := cn.gss.Continue(b) + if err == nil && !done { + w := cn.writeBuf('p') + w.bytes(tokOut) + cn.send(w) + } + + // Errors fall through and read the more detailed message + // from the server.. + + case 10: + sc := scram.NewClient(sha256.New, o["user"], o["password"]) + sc.Step(nil) + if sc.Err() != nil { + errorf("SCRAM-SHA-256 error: %s", sc.Err().Error()) + } + scOut := sc.Out() + + w := cn.writeBuf('p') + w.string("SCRAM-SHA-256") + w.int32(len(scOut)) + w.bytes(scOut) + cn.send(w) + + t, r := cn.recv() + if t != 'R' { + errorf("unexpected password response: %q", t) + } + + if r.int32() != 11 { + errorf("unexpected authentication response: %q", t) + } + + nextStep := r.next(len(*r)) + sc.Step(nextStep) + if sc.Err() != nil { + errorf("SCRAM-SHA-256 error: %s", sc.Err().Error()) + } + + scOut = sc.Out() + w = cn.writeBuf('p') + w.bytes(scOut) + cn.send(w) + + t, r = cn.recv() + if t != 'R' { + errorf("unexpected password response: %q", t) + } + + if r.int32() != 12 { + errorf("unexpected authentication response: %q", t) + } + + nextStep = r.next(len(*r)) + sc.Step(nextStep) + if sc.Err() != nil { + errorf("SCRAM-SHA-256 error: %s", sc.Err().Error()) + } + + 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{0, 1, 0, 1} + +// No result-column format codes (i.e. all text). +var colFmtDataAllText = []byte{0, 0} + +type stmt struct { + cn *conn + name string + rowsHeader + colFmtData []byte + paramTyps []oid.Oid + closed bool +} + +func (st *stmt) Close() (err error) { + if st.closed { + return nil + } + if err := st.cn.err.get(); err != nil { + return err + } + 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.err.set(driver.ErrBadConn) + errorf("unexpected close response: %q", t) + } + st.closed = true + + t, r := st.cn.recv1() + if t != 'Z' { + st.cn.err.set(driver.ErrBadConn) + 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) { + return st.query(v) +} + +func (st *stmt) query(v []driver.Value) (r *rows, err error) { + if err := st.cn.err.get(); err != nil { + return nil, err + } + defer st.cn.errRecover(&err) + + st.exec(v) + return &rows{ + cn: st.cn, + rowsHeader: st.rowsHeader, + }, nil +} + +func (st *stmt) Exec(v []driver.Value) (res driver.Result, err error) { + if err := st.cn.err.get(); err != nil { + return nil, err + } + 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.err.set(driver.ErrBadConn) + 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.err.set(driver.ErrBadConn) + errorf("could not parse commandTag: %s", err) + } + return driver.RowsAffected(n), commandTag +} + +type rowsHeader struct { + colNames []string + colTyps []fieldDesc + colFmts []format +} + +type rows struct { + cn *conn + finish func() + rowsHeader + done bool + rb readBuf + result driver.Result + tag string + + next *rowsHeader +} + +func (rs *rows) Close() error { + if finish := rs.finish; finish != nil { + defer finish() + } + // no need to look at cn.bad as Next() will + for { + err := rs.Next(nil) + switch err { + case nil: + case io.EOF: + // rs.Next can return io.EOF on both 'Z' (ready for query) and 'T' (row + // description, used with HasNextResultSet). We need to fetch messages until + // we hit a 'Z', which is done by waiting for done to be set. + if rs.done { + return nil + } + default: + return err + } + } +} + +func (rs *rows) Columns() []string { + return rs.colNames +} + +func (rs *rows) Result() driver.Result { + if rs.result == nil { + return emptyRows + } + return rs.result +} + +func (rs *rows) Tag() string { + return rs.tag +} + +func (rs *rows) Next(dest []driver.Value) (err error) { + if rs.done { + return io.EOF + } + + conn := rs.cn + if err := conn.err.getForNext(); err != nil { + return err + } + defer conn.errRecover(&err) + + for { + t := conn.recv1Buf(&rs.rb) + switch t { + case 'E': + err = parseError(&rs.rb) + case 'C', 'I': + if t == 'C' { + rs.result, rs.tag = conn.parseComplete(rs.rb.string()) + } + 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.err.set(driver.ErrBadConn) + 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].OID, rs.colFmts[i]) + } + return + case 'T': + next := parsePortalRowDescribe(&rs.rb) + rs.next = &next + return io.EOF + default: + errorf("unexpected message after execute: %q", t) + } + } +} + +func (rs *rows) HasNextResultSet() bool { + hasNext := rs.next != nil && !rs.done + return hasNext +} + +func (rs *rows) NextResultSet() error { + if rs.next == nil { + return io.EOF + } + rs.rowsHeader = *rs.next + rs.next = nil + return nil +} + +// 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" +// quoted := pq.QuoteIdentifier(tblname) +// err := db.Exec(fmt.Sprintf("INSERT INTO %s VALUES ($1)", quoted), 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) + `"` +} + +// QuoteLiteral quotes a 'literal' (e.g. a parameter, often used to pass literal +// to DDL and other statements that do not accept parameters) to be used as part +// of an SQL statement. For example: +// +// exp_date := pq.QuoteLiteral("2023-01-05 15:00:00Z") +// err := db.Exec(fmt.Sprintf("CREATE ROLE my_user VALID UNTIL %s", exp_date)) +// +// Any single quotes in name will be escaped. Any backslashes (i.e. "\") will be +// replaced by two backslashes (i.e. "\\") and the C-style escape identifier +// that PostgreSQL provides ('E') will be prepended to the string. +func QuoteLiteral(literal string) string { + // This follows the PostgreSQL internal algorithm for handling quoted literals + // from libpq, which can be found in the "PQEscapeStringInternal" function, + // which is found in the libpq/fe-exec.c source file: + // https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/interfaces/libpq/fe-exec.c + // + // substitute any single-quotes (') with two single-quotes ('') + literal = strings.Replace(literal, `'`, `''`, -1) + // determine if the string has any backslashes (\) in it. + // if it does, replace any backslashes (\) with two backslashes (\\) + // then, we need to wrap the entire string with a PostgreSQL + // C-style escape. Per how "PQEscapeStringInternal" handles this case, we + // also add a space before the "E" + if strings.Contains(literal, `\`) { + literal = strings.Replace(literal, `\`, `\\`, -1) + literal = ` E'` + literal + `'` + } else { + // otherwise, we can just wrap the literal with a pair of single quotes + literal = `'` + literal + `'` + } + return literal +} + +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 (cn *conn) processParameterStatus(r *readBuf) { + var err error + + param := r.string() + switch param { + case "server_version": + var major1 int + var major2 int + _, err = fmt.Sscanf(r.string(), "%d.%d", &major1, &major2) + if err == nil { + cn.parameterStatus.serverVersion = major1*10000 + major2*100 + } + + case "TimeZone": + cn.parameterStatus.currentLocation, err = time.LoadLocation(r.string()) + if err != nil { + cn.parameterStatus.currentLocation = nil + } + + default: + // ignore + } +} + +func (cn *conn) processReadyForQuery(r *readBuf) { + cn.txnStatus = transactionStatus(r.byte()) +} + +func (cn *conn) readReadyForQuery() { + t, r := cn.recv1() + switch t { + case 'Z': + cn.processReadyForQuery(r) + return + default: + cn.err.set(driver.ErrBadConn) + errorf("unexpected message %q; expected ReadyForQuery", t) + } +} + +func (cn *conn) processBackendKeyData(r *readBuf) { + cn.processID = r.int32() + cn.secretKey = r.int32() +} + +func (cn *conn) readParseResponse() { + t, r := cn.recv1() + switch t { + case '1': + return + case 'E': + err := parseError(r) + cn.readReadyForQuery() + panic(err) + default: + cn.err.set(driver.ErrBadConn) + errorf("unexpected Parse response %q", t) + } +} + +func (cn *conn) readStatementDescribeResponse() (paramTyps []oid.Oid, colNames []string, colTyps []fieldDesc) { + 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.err.set(driver.ErrBadConn) + errorf("unexpected Describe statement response %q", t) + } + } +} + +func (cn *conn) readPortalDescribeResponse() rowsHeader { + t, r := cn.recv1() + switch t { + case 'T': + return parsePortalRowDescribe(r) + case 'n': + return rowsHeader{} + case 'E': + err := parseError(r) + cn.readReadyForQuery() + panic(err) + default: + cn.err.set(driver.ErrBadConn) + 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.err.set(driver.ErrBadConn) + 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.err.set(driver.ErrBadConn) + 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.err.set(driver.ErrBadConn) + errorf("unexpected CommandComplete after error %s", err) + } + res, commandTag = cn.parseComplete(r.string()) + case 'Z': + cn.processReadyForQuery(r) + if res == nil && err == nil { + err = errUnexpectedReady + } + return res, commandTag, err + case 'E': + err = parseError(r) + case 'T', 'D', 'I': + if err != nil { + cn.err.set(driver.ErrBadConn) + errorf("unexpected %q after error %s", t, err) + } + if t == 'I' { + res = emptyRows + } + // ignore any results + default: + cn.err.set(driver.ErrBadConn) + errorf("unknown %s response: %q", protocolState, t) + } + } +} + +func parseStatementRowDescribe(r *readBuf) (colNames []string, colTyps []fieldDesc) { + n := r.int16() + colNames = make([]string, n) + colTyps = make([]fieldDesc, n) + for i := range colNames { + colNames[i] = r.string() + r.next(6) + colTyps[i].OID = r.oid() + colTyps[i].Len = r.int16() + colTyps[i].Mod = r.int32() + // format code not known when describing a statement; always 0 + r.next(2) + } + return +} + +func parsePortalRowDescribe(r *readBuf) rowsHeader { + n := r.int16() + colNames := make([]string, n) + colFmts := make([]format, n) + colTyps := make([]fieldDesc, n) + for i := range colNames { + colNames[i] = r.string() + r.next(6) + colTyps[i].OID = r.oid() + colTyps[i].Len = r.int16() + colTyps[i].Mod = r.int32() + colFmts[i] = format(r.int16()) + } + return rowsHeader{ + colNames: colNames, + colFmts: colFmts, + colTyps: colTyps, + } +} + +// 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 "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 +} |