1 files changed, 133 insertions, 0 deletions
diff --git a/libgo/go/database/sql/convert.go b/libgo/go/database/sql/convert.go
new file mode 100644
index 00000000000..9835e38de7e
--- /dev/null
+++ b/libgo/go/database/sql/convert.go
@@ -0,0 +1,133 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Type conversions for Scan.
+
+package sql
+
+import (
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+)
+
+// subsetTypeArgs takes a slice of arguments from callers of the sql
+// package and converts them into a slice of the driver package's
+// "subset types".
+func subsetTypeArgs(args []interface{}) ([]interface{}, error) {
+	out := make([]interface{}, len(args))
+	for n, arg := range args {
+		var err error
+		out[n], err = driver.DefaultParameterConverter.ConvertValue(arg)
+		if err != nil {
+			return nil, fmt.Errorf("sql: converting argument #%d's type: %v", n+1, err)
+		}
+	}
+	return out, nil
+}
+
+// convertAssign copies to dest the value in src, converting it if possible.
+// An error is returned if the copy would result in loss of information.
+// dest should be a pointer type.
+func convertAssign(dest, src interface{}) error {
+	// Common cases, without reflect.  Fall through.
+	switch s := src.(type) {
+	case string:
+		switch d := dest.(type) {
+		case *string:
+			*d = s
+			return nil
+		}
+	case []byte:
+		switch d := dest.(type) {
+		case *string:
+			*d = string(s)
+			return nil
+		case *[]byte:
+			*d = s
+			return nil
+		}
+	}
+
+	var sv reflect.Value
+
+	switch d := dest.(type) {
+	case *string:
+		sv = reflect.ValueOf(src)
+		switch sv.Kind() {
+		case reflect.Bool,
+			reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+			reflect.Float32, reflect.Float64:
+			*d = fmt.Sprintf("%v", src)
+			return nil
+		}
+	case *bool:
+		bv, err := driver.Bool.ConvertValue(src)
+		if err == nil {
+			*d = bv.(bool)
+		}
+		return err
+	}
+
+	if scanner, ok := dest.(ScannerInto); ok {
+		return scanner.ScanInto(src)
+	}
+
+	dpv := reflect.ValueOf(dest)
+	if dpv.Kind() != reflect.Ptr {
+		return errors.New("destination not a pointer")
+	}
+
+	if !sv.IsValid() {
+		sv = reflect.ValueOf(src)
+	}
+
+	dv := reflect.Indirect(dpv)
+	if dv.Kind() == sv.Kind() {
+		dv.Set(sv)
+		return nil
+	}
+
+	switch dv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		s := asString(src)
+		i64, err := strconv.ParseInt(s, 10, dv.Type().Bits())
+		if err != nil {
+			return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err)
+		}
+		dv.SetInt(i64)
+		return nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		s := asString(src)
+		u64, err := strconv.ParseUint(s, 10, dv.Type().Bits())
+		if err != nil {
+			return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err)
+		}
+		dv.SetUint(u64)
+		return nil
+	case reflect.Float32, reflect.Float64:
+		s := asString(src)
+		f64, err := strconv.ParseFloat(s, dv.Type().Bits())
+		if err != nil {
+			return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err)
+		}
+		dv.SetFloat(f64)
+		return nil
+	}
+
+	return fmt.Errorf("unsupported driver -> Scan pair: %T -> %T", src, dest)
+}
+
+func asString(src interface{}) string {
+	switch v := src.(type) {
+	case string:
+		return v
+	case []byte:
+		return string(v)
+	}
+	return fmt.Sprintf("%v", src)
+}