nsscash: support longer lines in passwd/group files

[nsscash/nsscash.git] / group.go

diff --git a/group.go b/group.go
index 7cc084187d15f613d140f251eef5cfdfea0d4751..214f91438d78740a331c487cbfe5ecab1355718c 100644 (file)
--- a/group.go
+++ b/group.go
@@ -39,11 +39,13 @@ type Group struct {
        Gid     uint64
        Members []string
 }
+
+// Go does not support slices in map keys; therefore, use this separate struct
 type GroupKey struct {
        Name    string
        Passwd  string
        Gid     uint64
-       Members string
+       Members string // "," separated
 }
 
 func toKey(g Group) GroupKey {
@@ -56,13 +58,19 @@ func toKey(g Group) GroupKey {
 }
 
 // ParseGroups parses a file in the format of /etc/group and returns all
-// entries as Group structs.
+// entries as slice of Group structs.
 func ParseGroups(r io.Reader) ([]Group, error) {
        var res []Group
 
-       s := bufio.NewScanner(r)
-       for s.Scan() {
-               t := s.Text()
+       s := bufio.NewReader(r)
+       for {
+               t, err := s.ReadString('\n')
+               if err != nil {
+                       if err == io.EOF {
+                               break
+                       }
+                       return nil, err
+               }
 
                x := strings.Split(t, ":")
                if len(x) != 4 {
@@ -74,6 +82,9 @@ func ParseGroups(r io.Reader) ([]Group, error) {
                        return nil, errors.Wrapf(err, "invalid gid in line %q", t)
                }
 
+               // ReadString() contains the delimiter
+               x[3] = strings.TrimSuffix(x[3], "\n")
+
                var members []string
                // No members must result in empty slice, not slice with the
                // empty string
@@ -87,10 +98,6 @@ func ParseGroups(r io.Reader) ([]Group, error) {
                        Members: members,
                })
        }
-       err := s.Err()
-       if err != nil {
-               return nil, err
-       }
 
        return res, nil
 }
@@ -112,10 +119,7 @@ func SerializeGroup(g Group) []byte {
        offPasswd := uint16(data.Len())
        data.Write([]byte(g.Passwd))
        data.WriteByte(0)
-       // Padding to align the following uint16
-       if data.Len()%2 != 0 {
-               data.WriteByte(0)
-       }
+       alignBufferTo(&data, 2) // align the following uint16
        offMemOff := uint16(data.Len())
        // Offsets for group members
        offMem := offMemOff + 2*uint16(len(mems_off))
@@ -152,12 +156,7 @@ func SerializeGroup(g Group) []byte {
        res.Write(data.Bytes())
        // We must pad each entry so that all uint64 at the beginning of the
        // struct are 8 byte aligned
-       l := res.Len()
-       if l%8 != 0 {
-               for i := 0; i < 8-l%8; i++ {
-                       res.WriteByte(0)
-               }
-       }
+       alignBufferTo(&res, 8)
 
        return res.Bytes()
 }