libcore/Function2.h

   1 //
   2 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010,
   3 //   2011 Free Software Foundation, Inc
   4 //
   5 // This program is free software; you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation; either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // This program is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with this program; if not, write to the Free Software
  17 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18
  19 #ifndef GNASH_FUNCTION2_H
  20 #define GNASH_FUNCTION2_H
  21
  22 #include <vector>
  23 #include <cassert>
  24 #include <string>
  25
  26 #include "Function.h"
  27 #include "smart_ptr.h"
  28
  29 // Forward declarations
  30 namespace gnash {
  31     class action_buffer;
  32     class as_object;
  33 }
  34
  35 namespace gnash {
  36
  37 /// Function2 adds extra sauce to ordinary Functions.
  38 //
  39 /// The Function2 was introduced in version 6 of the player. Differences from
  40 /// ordinary functions are:
  41 /// 1. Up to 256 local registers.
  42 /// 2. Ability to suppress super, this, arguments
  43 /// 3. Ability to store super, this, arguments, _global, _root, and _parent
  44 ///    in registers.
  45 class Function2 : public Function
  46 {
  47
  48 public:
  49
  50         enum DefineFunction2Flags
  51         {
  52                 /// Bind one register to "this"
  53                 PRELOAD_THIS = 0x01,
  54
  55                 /// No "this" variable accessible by name
  56                 SUPPRESS_THIS = 0x02,
  57
  58                 /// Bind one register to "arguments"
  59                 PRELOAD_ARGUMENTS = 0x04,
  60
  61                 /// No "argument" variable accessible by name
  62                 SUPPRESS_ARGUMENTS = 0x08,
  63
  64                 /// Bind one register to "super"
  65                 PRELOAD_SUPER = 0x10,
  66
  67                 /// No "super" variable accessible by name
  68                 SUPPRESS_SUPER = 0x20,
  69
  70                 /// Bind one register to "_root"
  71                 PRELOAD_ROOT = 0x40,
  72
  73                 /// Bind one register to "_parent"
  74                 PRELOAD_PARENT = 0x80,
  75
  76                 /// Bind one register to "_global"
  77                 PRELOAD_GLOBAL = 256
  78         };
  79
  80     // Create a function defined in a DefineFunction2 opcode.
  81         Function2(const action_buffer& ab, as_environment& env, size_t start,
  82                 const ScopeStack& with_stack);
  83
  84         virtual ~Function2() {}
  85
  86     /// Return the number of registers to allocate for this function.
  87     virtual boost::uint8_t registers() const {
  88         return _registerCount;
  89     }
  90
  91         void setRegisterCount(boost::uint8_t ct) {
  92         _registerCount = ct;
  93     }
  94
  95         void setFlags(boost::uint16_t flags) {
  96         _function2Flags = flags;
  97     }
  98
  99         /// Dispatch.
 100         virtual as_value call(const fn_call& fn);
 101
 102 private:
 103
 104     /// The number of registers required.
 105         boost::uint8_t _registerCount;
 106
 107         /// Used to control implicit arg register assignments
 108         boost::uint16_t _function2Flags;
 109
 110 };
 111
 112
 113 } // end of gnash namespace
 114
 115 #endif
 116