vala/valaunlockstatement.vala

   1 /* valaunlockstatement.vala
   2  *
   3  * Copyright (C) 2009-2010  Jürg Billeter
   4  * Copyright (C) 2009  Jiří Zárevúcky
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  19  *
  20  * Author:
  21  *      Jiří Zárevúcky <zarevucky.jiri@gmail.com>
  22  */
  23
  24 /**
  25  * Represents an unlock statement e.g. {{{ unlock (a); }}}.
  26  */
  27 public class Vala.UnlockStatement : CodeNode, Statement {
  28         /**
  29          * Expression representing the resource to be unlocked.
  30          */
  31         public Expression resource { get; set; }
  32
  33         public UnlockStatement (Expression resource, SourceReference? source_reference = null) {
  34                 this.source_reference = source_reference;
  35                 this.resource = resource;
  36         }
  37
  38         public override void accept (CodeVisitor visitor) {
  39                 resource.accept (visitor);
  40                 visitor.visit_unlock_statement (this);
  41         }
  42
  43         public override bool check (CodeContext context) {
  44                 if (checked) {
  45                         return !error;
  46                 }
  47
  48                 checked = true;
  49
  50                 resource.check (context);
  51
  52                 /* resource must be a member access and denote a Lockable */
  53                 if (!(resource is MemberAccess && resource.symbol_reference is Lockable)) {
  54                         error = true;
  55                         resource.error = true;
  56                         Report.error (resource.source_reference, "Expression is either not a member access or does not denote a lockable member");
  57                         return false;
  58                 }
  59
  60                 /* parent symbol must be the current class */
  61                 if (resource.symbol_reference.parent_symbol != context.analyzer.current_class) {
  62                         error = true;
  63                         resource.error = true;
  64                         Report.error (resource.source_reference, "Only members of the current class are lockable");
  65                 }
  66
  67                 ((Lockable) resource.symbol_reference).lock_used = true;
  68
  69                 return !error;
  70         }
  71
  72         public override void emit (CodeGenerator codegen) {
  73                 resource.emit (codegen);
  74                 codegen.visit_unlock_statement (this);
  75         }
  76 }