generate_function.lua

   1 #!/usr/bin/lua
   2
   3 HEADER_DEFINE = tostring(os.getenv'HEADER_DEFINE' or '__LQT_FUNCTION')
   4 ARG_MAX = tonumber(os.getenv'ARG_MAX' or 2)
   5 TYPES = { bool='lua_pushboolean', int='lua_pushinteger', double='lua_pushnumber', ['const char *']='lua_pushstring' }
   6
   7 cpp = {
   8   string = '',
   9   write = function (s)
  10     cpp.string = cpp.string .. tostring(s)
  11   end,
  12 }
  13
  14 hpp = {
  15   string = '',
  16   write = function (s)
  17     hpp.string = hpp.string .. tostring(s)
  18   end,
  19 }
  20
  21 hpp.write("#ifndef "..HEADER_DEFINE.."\n")
  22 hpp.write("#define "..HEADER_DEFINE.."\n")
  23 cpp.write('#include "lqt_function.hpp"\n ')
  24
  25
  26 hpp.write[[
  27
  28 #include "lqt_common.hpp"
  29
  30 #include <QObject>
  31 //#include <QDebug>
  32
  33 #define LUA_FUNCTION_REGISTRY "Registry Function"
  34 //#ifndef SEE_STACK
  35 //# define SEE_STACK(L, j) for (int j=1;j<=lua_gettop(L);j++) { qDebug() << j << '=' << luaL_typename(L, j) << '@' << lua_topointer (L, j); }
  36 //#endif
  37
  38 class LuaFunction: public QObject {
  39   Q_OBJECT
  40
  41   public:
  42   LuaFunction(lua_State *state);
  43   virtual ~LuaFunction();
  44
  45   private:
  46     lua_State *L;
  47     static int __gc (lua_State *L);
  48   protected:
  49   public:
  50   public slots:
  51 ]]
  52 cpp.write[[
  53 LuaFunction::LuaFunction(lua_State *state):L(state) {
  54         int functionTable = lua_gettop(L); // not yet but soon
  55         //qDebug() << "Function" << this << "is born";
  56         lua_getfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
  57         if (lua_isnil(L, -1)) {
  58                 lua_pop(L, 1);
  59                 lua_newtable(L);
  60                 lua_pushvalue(L, -1);
  61                 lua_setfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
  62         }
  63         lua_insert(L, -2);
  64
  65         lua_pushvalue(L, -1);
  66         lua_gettable(L, functionTable);
  67
  68         if (!lqtL_testudata(L, -1, "QObject*")) {
  69                 //qDebug() << "not QObject* is" << luaL_typename(L, -1);
  70                 lua_pop(L, 1);
  71                 // top of stack is the function I want
  72                 //qDebug() << "to be bound is" << luaL_typename(L, -1);
  73                 lua_pushlightuserdata(L, this);
  74                 lua_pushvalue(L, -2);
  75                 lua_settable(L, functionTable);
  76                 // registry this is associated to this function
  77                 lqtL_passudata(L, this, "QObject*");
  78                 lua_insert(L, -2);
  79                 lua_pushvalue(L, -2);
  80                 lua_settable(L, functionTable);
  81         } else {
  82                 // leave the qobject on top;
  83                 //qDebug() << "Function" << this << "scheduled for deletion";
  84                 this->deleteLater();
  85         }
  86         lua_replace(L, functionTable);
  87         lua_settop(L, functionTable);
  88 }
  89 LuaFunction::~LuaFunction() {
  90         //qDebug() << "Function" << this << "is dead";
  91         lua_getfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
  92         lua_pushlightuserdata(L, this);
  93         lua_gettable(L, -2);
  94         lua_pushnil(L);
  95         lua_settable(L, -3);
  96         lua_pushlightuserdata(L, this);
  97         lua_pushnil(L);
  98         lua_settable(L, -3);
  99         lua_pop(L, 1);
 100 }
 101 ]]
 102 --[[
 103 int LuaFunction::__gc (lua_State *L) {
 104   QPointer<QObject> *qp = (QPointer<QObject> *)lua_touserdata(L, 1);
 105   if (*qp) {
 106     (*qp)->deleteLater();
 107   }
 108     qDebug() << "LuaFunction" << *qp << "scheduled for deletion";
 109     return 0;
 110   }
 111 ]]
 112
 113 signatures = {
 114   [0] = {
 115     [''] = '',
 116   }
 117 }
 118
 119 for nargs = 1,ARG_MAX do
 120   signatures[nargs] = {}
 121   for oldsig, oldbody in pairs(signatures[nargs-1]) do
 122     for argtype, argpush in pairs(TYPES) do
 123       signatures[nargs][oldsig..((nargs==1) and '' or ', ')..argtype..' arg'..tostring(nargs)] = oldbody..argpush.."(L, arg"..tostring(nargs)..');'
 124     end
 125   end
 126 end
 127
 128 for i=0,ARG_MAX do
 129   for s, b in pairs(signatures[i]) do
 130     hpp.write('  void function ('..s..');\n')
 131     cpp.write'void LuaFunction::function ('
 132     cpp.write(s)
 133     cpp.write[[) {
 134   int functionTable = lua_gettop(L) + 1;
 135   lua_getfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
 136   if (!lua_istable(L, -1)) {
 137     return;
 138   }
 139   lua_pushlightuserdata(L, this);
 140   lua_gettable(L, functionTable);
 141   ]]
 142     cpp.write(b)
 143     cpp.write'\n  '
 144     cpp.write'lua_call(L,'
 145     cpp.write(tostring(i))
 146     cpp.write', 0);\n'
 147     cpp.write[[
 148 };]]
 149     cpp.write'\n'
 150   end
 151 end
 152
 153 hpp.write[[
 154 };
 155
 156
 157 ]]
 158 hpp.write("#endif // "..HEADER_DEFINE.."\n")
 159
 160
 161 io.write(hpp.string)
 162