database/sql: convert SQL null values to []byte as nil.
Also allow string values to scan into []byte.
Fixes #2788.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5577054
diff --git a/src/pkg/database/sql/sql.go b/src/pkg/database/sql/sql.go
index 7e226b1..34a7652 100644
--- a/src/pkg/database/sql/sql.go
+++ b/src/pkg/database/sql/sql.go
@@ -904,6 +904,12 @@
if !ok {
continue
}
+ if *b == nil {
+ // If the []byte is now nil (for a NULL value),
+ // don't fall through to below which would
+ // turn it into a non-nil 0-length byte slice
+ continue
+ }
if _, ok = dp.(*RawBytes); ok {
continue
}
@@ -945,17 +951,10 @@
if r.err != nil {
return r.err
}
- defer r.rows.Close()
- if !r.rows.Next() {
- return ErrNoRows
- }
- err := r.rows.Scan(dest...)
- if err != nil {
- return err
- }
// TODO(bradfitz): for now we need to defensively clone all
- // []byte that the driver returned, since we're about to close
+ // []byte that the driver returned (not permitting
+ // *RawBytes in Rows.Scan), since we're about to close
// the Rows in our defer, when we return from this function.
// the contract with the driver.Next(...) interface is that it
// can return slices into read-only temporary memory that's
@@ -970,14 +969,17 @@
if _, ok := dp.(*RawBytes); ok {
return errors.New("sql: RawBytes isn't allowed on Row.Scan")
}
- b, ok := dp.(*[]byte)
- if !ok {
- continue
- }
- clone := make([]byte, len(*b))
- copy(clone, *b)
- *b = clone
}
+
+ defer r.rows.Close()
+ if !r.rows.Next() {
+ return ErrNoRows
+ }
+ err := r.rows.Scan(dest...)
+ if err != nil {
+ return err
+ }
+
return nil
}
