update go-sql-driver/mysql vendor files

vendor/github.com/go-sql-driver/mysql/statement.go

@@ -10,6 +10,9 @@ package mysql
 
 import (
 	"database/sql/driver"
+	"fmt"
+	"reflect"
+	"strconv"
 )
 
 type mysqlStmt struct {
@@ -21,7 +24,10 @@ type mysqlStmt struct {
 
 func (stmt *mysqlStmt) Close() error {
 	if stmt.mc == nil || stmt.mc.netConn == nil {
-		errLog.Print(errInvalidConn)
+		// driver.Stmt.Close can be called more than once, thus this function
+		// has to be idempotent.
+		// See also Issue #450 and golang/go#16019.
+		//errLog.Print(ErrInvalidConn)
 		return driver.ErrBadConn
 	}
 
@@ -34,9 +40,13 @@ func (stmt *mysqlStmt) NumInput() int {
 	return stmt.paramCount
 }
 
+func (stmt *mysqlStmt) ColumnConverter(idx int) driver.ValueConverter {
+	return converter{}
+}
+
 func (stmt *mysqlStmt) Exec(args []driver.Value) (driver.Result, error) {
 	if stmt.mc.netConn == nil {
-		errLog.Print(errInvalidConn)
+		errLog.Print(ErrInvalidConn)
 		return nil, driver.ErrBadConn
 	}
 	// Send command
@@ -76,7 +86,7 @@ func (stmt *mysqlStmt) Exec(args []driver.Value) (driver.Result, error) {
 
 func (stmt *mysqlStmt) Query(args []driver.Value) (driver.Rows, error) {
 	if stmt.mc.netConn == nil {
-		errLog.Print(errInvalidConn)
+		errLog.Print(ErrInvalidConn)
 		return nil, driver.ErrBadConn
 	}
 	// Send command
@@ -94,9 +104,9 @@ func (stmt *mysqlStmt) Query(args []driver.Value) (driver.Rows, error) {
 	}
 
 	rows := new(binaryRows)
-	rows.mc = mc
 
 	if resLen > 0 {
+		rows.mc = mc
 		// Columns
 		// If not cached, read them and cache them
 		if stmt.columns == nil {
@@ -110,3 +120,34 @@ func (stmt *mysqlStmt) Query(args []driver.Value) (driver.Rows, error) {
 
 	return rows, err
 }
+
+type converter struct{}
+
+func (c converter) ConvertValue(v interface{}) (driver.Value, error) {
+	if driver.IsValue(v) {
+		return v, nil
+	}
+
+	rv := reflect.ValueOf(v)
+	switch rv.Kind() {
+	case reflect.Ptr:
+		// indirect pointers
+		if rv.IsNil() {
+			return nil, nil
+		}
+		return c.ConvertValue(rv.Elem().Interface())
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return rv.Int(), nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32:
+		return int64(rv.Uint()), nil
+	case reflect.Uint64:
+		u64 := rv.Uint()
+		if u64 >= 1<<63 {
+			return strconv.FormatUint(u64, 10), nil
+		}
+		return int64(u64), nil
+	case reflect.Float32, reflect.Float64:
+		return rv.Float(), nil
+	}
+	return nil, fmt.Errorf("unsupported type %T, a %s", v, rv.Kind())
+}