diff --git a/glib/gvariant.c b/glib/gvariant.c index 5948ccda6..9e63dabc2 100644 --- a/glib/gvariant.c +++ b/glib/gvariant.c @@ -1765,7 +1765,7 @@ g_variant_print (GVariant *value, FALSE); }; -/* Hash, Equal {{{1 */ +/* Hash, Equal, Compare {{{1 */ /** * g_variant_hash: * @value: a basic #GVariant value as a #gconstpointer @@ -1917,6 +1917,109 @@ g_variant_equal (gconstpointer one, return equal; } +/** + * g_variant_compare: + * @one: a basic-typed #GVariant instance + * @two: a #GVariant instance of the same type + * @returns: negative value if a < b; + * zero if a = b; + * positive value if a > b. + * + * Compares @one and @two. + * + * The types of @one and @two are #gconstpointer only to allow use of + * this function with #GTree, #GPtrArray, etc. They must each be a + * #GVariant. + * + * Comparison is only defined for basic types (ie: booleans, numbers, + * strings). For booleans, %FALSE is less than %TRUE. Numbers are + * ordered in the usual way. Strings are in ASCII lexographical order. + * + * It is a programmer error to attempt to compare container values or + * two values that have types that are not exactly equal. For example, + * you can not compare a 32-bit signed integer with a 32-bit unsigned + * integer. Also note that this function is not particularly + * well-behaved when it comes to comparison of doubles; in particular, + * the handling of incomparable values (ie: NaN) is undefined. + * + * If you only require an equality comparison, g_variant_equal() is more + * general. + **/ +gint +g_variant_compare (gconstpointer one, + gconstpointer two) +{ + GVariant *a = (GVariant *) one; + GVariant *b = (GVariant *) two; + + g_return_val_if_fail (g_variant_classify (a) == g_variant_classify (b), 0); + + switch (g_variant_classify (a)) + { + case G_VARIANT_CLASS_BYTE: + return ((gint) g_variant_get_byte (a)) - + ((gint) g_variant_get_byte (b)); + + case G_VARIANT_CLASS_INT16: + return ((gint) g_variant_get_int16 (a)) - + ((gint) g_variant_get_int16 (b)); + + case G_VARIANT_CLASS_UINT16: + return ((gint) g_variant_get_uint16 (a)) - + ((gint) g_variant_get_uint16 (b)); + + case G_VARIANT_CLASS_INT32: + { + gint32 a_val = g_variant_get_int32 (a); + gint32 b_val = g_variant_get_int32 (b); + + return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1; + } + + case G_VARIANT_CLASS_UINT32: + { + guint32 a_val = g_variant_get_uint32 (a); + guint32 b_val = g_variant_get_uint32 (b); + + return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1; + } + + case G_VARIANT_CLASS_INT64: + { + gint64 a_val = g_variant_get_int64 (a); + gint64 b_val = g_variant_get_int64 (b); + + return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1; + } + + case G_VARIANT_CLASS_UINT64: + { + guint64 a_val = g_variant_get_int32 (a); + guint64 b_val = g_variant_get_int32 (b); + + return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1; + } + + case G_VARIANT_CLASS_DOUBLE: + { + gdouble a_val = g_variant_get_double (a); + gdouble b_val = g_variant_get_double (b); + + return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1; + } + + case G_VARIANT_CLASS_STRING: + case G_VARIANT_CLASS_OBJECT_PATH: + case G_VARIANT_CLASS_SIGNATURE: + return strcmp (g_variant_get_string (a, NULL), + g_variant_get_string (b, NULL)); + + default: + g_return_val_if_fail (!g_variant_is_container (a), 0); + g_assert_not_reached (); + } +} + /* GVariantIter {{{1 */ /** * GVariantIter: