Allow user use dsn without dbname

Allow user use dsn without dbname

.gitignore

@@ -0,0 +1,2 @@
+
+.DS_Store

driver.go

@@ -12,7 +12,6 @@ import (
 	"bufio"
 	"database/sql"
 	"database/sql/driver"
-	"errors"
 	"net"
 )
 
@@ -28,11 +27,6 @@ func (d *mysqlDriver) Open(dsn string) (driver.Conn, error) {
 	mc := new(mysqlConn)
 	mc.cfg = parseDSN(dsn)
 
-	if mc.cfg.dbname == "" {
-		e = errors.New("Incomplete or invalid DSN")
-		return nil, e
-	}
-
 	// Connect to Server
 	mc.netConn, e = net.Dial(mc.cfg.net, mc.cfg.addr)
 	if e != nil {

packets.go

@@ -208,16 +208,19 @@ func (mc *mysqlConn) writeAuthPacket() (e error) {
 	if mc.server.flags&CLIENT_LONG_FLAG > 0 {
 		clientFlags |= uint32(CLIENT_LONG_FLAG)
 	}
+
+	// User Password
+	scrambleBuff := scramblePassword(mc.server.scrambleBuff, []byte(mc.cfg.passwd))
+
+	pktLen := 4 + 4 + 1 + 23 + len(mc.cfg.user) + 1 + 1 + len(scrambleBuff) 
+
 	// To specify a db name
 	if len(mc.cfg.dbname) > 0 {
 		clientFlags |= uint32(CLIENT_CONNECT_WITH_DB)
+		pktLen += len(mc.cfg.dbname) + 1 
 	}
 
-	// User Password
-	scrambleBuff := scramblePassword(mc.server.scrambleBuff, []byte(mc.cfg.passwd))
-
 	// Calculate packet length and make buffer with that size
-	pktLen := 4 + 4 + 1 + 23 + len(mc.cfg.user) + 1 + 1 + len(scrambleBuff) + len(mc.cfg.dbname) + 1
 	data := make([]byte, 0, pktLen+4)
 
 	// Add the packet header
@@ -338,7 +341,7 @@ func (mc *mysqlConn) readResultOK() (e error) {
 		return mc.handleOkPacket(data)
 	// EOF, someone is using old_passwords
 	case 254:
-		e = errors.New("It seems like you are using old_passwords, which is unsupported. See https://github.com/Go-SQL-Driver/MySQL/wiki/old_passwords")
+		e = errors.New("It seems like you are using old_passwords, which is unsupported. See http://code.google.com/p/go-mysql-driver/wiki/old_passwords")
 		return
 	// ERROR
 	case 255: