libcore/Function2.h

   1 //
   2 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
   3 //   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 "Function.h"
  23
  24 // Forward declarations
  25 namespace gnash {
  26     class action_buffer;
  27     class as_object;
  28 }
  29
  30 namespace gnash {
  31
  32 /// Function2 adds extra sauce to ordinary Functions.
  33 //
  34 /// The Function2 was introduced in version 6 of the player. Differences from
  35 /// ordinary functions are:
  36 /// 1. Up to 256 local registers.
  37 /// 2. Ability to suppress super, this, arguments
  38 /// 3. Ability to store super, this, arguments, _global, _root, and _parent
  39 ///    in registers.
  40 class Function2 : public Function
  41 {
  42
  43 public:
  44
  45         enum DefineFunction2Flags
  46         {
  47                 /// Bind one register to "this"
  48                 PRELOAD_THIS = 0x01,
  49
  50                 /// No "this" variable accessible by name
  51                 SUPPRESS_THIS = 0x02,
  52
  53                 /// Bind one register to "arguments"
  54                 PRELOAD_ARGUMENTS = 0x04,
  55
  56                 /// No "argument" variable accessible by name
  57                 SUPPRESS_ARGUMENTS = 0x08,
  58
  59                 /// Bind one register to "super"
  60                 PRELOAD_SUPER = 0x10,
  61
  62                 /// No "super" variable accessible by name
  63                 SUPPRESS_SUPER = 0x20,
  64
  65                 /// Bind one register to "_root"
  66                 PRELOAD_ROOT = 0x40,
  67
  68                 /// Bind one register to "_parent"
  69                 PRELOAD_PARENT = 0x80,
  70
  71                 /// Bind one register to "_global"
  72                 PRELOAD_GLOBAL = 256
  73         };
  74
  75     // Create a function defined in a DefineFunction2 opcode.
  76         Function2(const action_buffer& ab, as_environment& env, size_t start,
  77                 const ScopeStack& with_stack);
  78
  79         virtual ~Function2() {}
  80
  81     /// Return the number of registers to allocate for this function.
  82     virtual boost::uint8_t registers() const {
  83         return _registerCount;
  84     }
  85
  86         void setRegisterCount(boost::uint8_t ct) {
  87         _registerCount = ct;
  88     }
  89
  90         void setFlags(boost::uint16_t flags) {
  91         _function2Flags = flags;
  92     }
  93
  94         /// Dispatch.
  95         virtual as_value call(const fn_call& fn);
  96
  97 private:
  98
  99     /// The number of registers required.
 100         boost::uint8_t _registerCount;
 101
 102         /// Used to control implicit arg register assignments
 103         boost::uint16_t _function2Flags;
 104
 105 };
 106
 107
 108 } // end of gnash namespace
 109
 110 #endif
 111