libgo/runtime/go-typedesc-equal.c

   1 /* go-typedesc-equal.c -- return whether two type descriptors are equal.
   2
   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.  */
   6
   7 #include "runtime.h"
   8 #include "go-string.h"
   9 #include "go-type.h"
  10
  11 /* Compare type descriptors for equality.  This is necessary because
  12    types may have different descriptors in different shared libraries.
  13    Also, unnamed types may have multiple type descriptors even in a
  14    single shared library.  */
  15
  16 _Bool
  17 __go_type_descriptors_equal (const struct __go_type_descriptor *td1,
  18                              const struct __go_type_descriptor *td2)
  19 {
  20   if (td1 == td2)
  21     return 1;
  22   /* In a type switch we can get a NULL descriptor.  */
  23   if (td1 == NULL || td2 == NULL)
  24     return 0;
  25   if (td1->__code != td2->__code || td1->__hash != td2->__hash)
  26     return 0;
  27   if (td1->__uncommon != NULL && td1->__uncommon->__name != NULL)
  28     {
  29       if (td2->__uncommon == NULL || td2->__uncommon->__name == NULL)
  30         return 0;
  31       return (__go_ptr_strings_equal (td1->__uncommon->__name,
  32                                       td2->__uncommon->__name)
  33               && __go_ptr_strings_equal (td1->__uncommon->__pkg_path,
  34                                          td2->__uncommon->__pkg_path));
  35     }
  36   if (td2->__uncommon != NULL && td2->__uncommon->__name != NULL)
  37     return 0;
  38   return __go_ptr_strings_equal (td1->__reflection, td2->__reflection);
  39 }