#This script is designed to run with Understand - CodeCheck
use base qw(Understand::Codecheck);
use strict;


use Codecheck::Libraries::InfoSiftr qw(resolveTypedefs);

use constant ERR1 => 'Violation: union used for "%1".';
use constant ERR2 => 'Violation: union "%1" is invalid.';

sub register_tr_text {
	my $check = shift;
	$check->add_tr_text(ERR1);
	$check->add_tr_text(ERR2);
}

sub name { '18.4 Unions shall not be used' }

sub description { '18.4 (Required) Unions shall not be used.' }

sub detailed_description { <<'END_DESC'
Rule 18.3 prohibits the reuse of memory areas for unrelated purposes. However, even when memory is being reused for related purposes, there is still a risk that the data may be misinterpreted.  Therefore, this rule prohibits the use of unions for any purpose.
END_DESC
}

sub test_language {
	my $language = shift;
	return $language eq 'C++';
}

sub test_entity { 0 }

sub test_global { 1 }

sub define_options { }

sub check {
	my $check = shift;
   my %typelist;
  
	foreach my $file ($check->get_files) {
   my $type;
	
	foreach my $ref ($file->filerefs('define, declare', 'union', 0)) {
		$check->violation($ref->ent, $ref->file, $ref->line, $ref->column, ERR2, $ref->ent->longname);
	}
	
	foreach my $ref ($file->filerefs('define, declare', 'object, typedef', 0)) {
		if($typelist{$ref->ent->type}){
      $type = $typelist{$ref->ent->type};
     }
    else{
      $type = resolveTypedefs($ref->ent->type, $check->db);
      $typelist{$ref->ent->type} = $type;
    }
		next unless $type =~ m! \b union \b !x;
		
		$check->violation($ref->ent, $ref->file, $ref->line, $ref->column, ERR1, $ref->ent->longname);
	}
	}
	return;
}