categoricals: Improve comments.

[pspp] / src / ui / gui / value-variant.c

diff --git a/src/ui/gui/value-variant.c b/src/ui/gui/value-variant.c
index e8c342b7bb33ecc19089888342786fbde1b90b41..ce523ae14ea54073ccf66edb37c00769f304e440 100644 (file)
--- a/src/ui/gui/value-variant.c
+++ b/src/ui/gui/value-variant.c
@@ -28,7 +28,10 @@ enum
     IDX_DATA
   };
 
-
+/* Returns a GVariant containing the data contained
+   in IN and WIDTH.  The returned GVariant has a floating
+   reference.
+ */
 GVariant *
 value_variant_new (const union value *in, int width)
 {
@@ -52,20 +55,24 @@ value_variant_new (const union value *in, int width)
       vv[IDX_DATA] = g_variant_new_from_data (G_VARIANT_TYPE_BYTESTRING, q,
                                              width + 1, FALSE, NULL, NULL);
     }
-  
+
   return g_variant_new_tuple (vv, 2);
 }
 
+/* Destroy the contents of VAL.  Also unref V */
 void
 value_destroy_from_variant (union value *val, GVariant *v)
 {
   GVariant *vwidth = g_variant_get_child_value (v, IDX_WIDTH);
-  gint32 width = g_variant_get_int32 (vwidth);
+  gint32 width = g_variant_get_int32 (vwidth); /* v is unreffed here */
   g_variant_unref (vwidth);
   value_destroy (val, width);
 }
 
 
+/* Fills VAL with the value data held in V.
+   When VAL is no longer required it must be destroyed using
+   value_destroy_from_variant. */
 void
 value_variant_get (union value *val, GVariant *v)
 {
@@ -80,12 +87,11 @@ value_variant_get (union value *val, GVariant *v)
   else
     {
       const gchar *data = g_variant_get_bytestring (vdata);
+      size_t len = strlen (data);
       if (width <= MAX_SHORT_STRING)
-       memcpy (val->short_string, data, MAX_SHORT_STRING);
+       memcpy (val->short_string, data, MIN (MAX_SHORT_STRING, len));
       else
-       {
-         val->long_string = xmemdup (data, width);
-       }
+       val->long_string = xmemdup (data, MIN (width, len));
     }
 
   g_variant_unref (vdata);