/cp
[official-gcc.git] / libgo / runtime / go-interface-compare.c
blob6374bd2fb428d72cec873939c234f4d7ac0ab8dd
1 /* go-interface-compare.c -- compare two interface values.
3 Copyright 2009 The Go Authors. All rights reserved.
4 Use of this source code is governed by a BSD-style
5 license that can be found in the LICENSE file. */
7 #include <stddef.h>
9 #include "runtime.h"
10 #include "go-type.h"
11 #include "interface.h"
13 /* Compare two interface values. Return 0 for equal, not zero for not
14 equal (return value is like strcmp). */
16 int
17 __go_interface_compare (struct __go_interface left,
18 struct __go_interface right)
20 const struct __go_type_descriptor *left_descriptor;
22 if (left.__methods == NULL && right.__methods == NULL)
23 return 0;
24 if (left.__methods == NULL || right.__methods == NULL)
25 return 1;
26 left_descriptor = left.__methods[0];
27 if (!__go_type_descriptors_equal (left_descriptor, right.__methods[0]))
28 return 1;
29 if (__go_is_pointer_type (left_descriptor))
30 return left.__object == right.__object ? 0 : 1;
31 if (!left_descriptor->__equalfn (left.__object, right.__object,
32 left_descriptor->__size))
33 return 1;
34 return 0;