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 "luafunction.hpp"\n ')
  24
  25
  26 hpp.write[[
  27
  28 #include "common_bind.hpp"
  29
  30 #include <QObject>
  31 #include <QDebug>
  32
  33 #define LUA_FUNCTION_REGISTRY "LuaFunction"
  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 ]]
  44 cpp.write[[
  45 LuaFunction::LuaFunction(lua_State *state):L(state) {
  46     int functionTable = lua_gettop(L); // not yet but soon
  47     qDebug() << "Function" << this << "is born";
  48     lua_getfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
  49     if (lua_isnil(L, -1)) {
  50       lua_pop(L, 1);
  51       lua_newtable(L);
  52       lua_pushvalue(L, -1);
  53       lua_setfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
  54     }
  55     lua_insert(L, -2);
  56
  57     lua_pushvalue(L, -1);
  58     lua_gettable(L, functionTable);
  59
  60     if (!lqtL_testudata(L, -1, "QObject*")) {
  61       qDebug() << "not QObject* is" << luaL_typename(L, -1);
  62       lua_pop(L, 1);
  63       // top of stack is the function I want
  64       qDebug() << "to be bound is" << luaL_typename(L, -1);
  65       lua_pushlightuserdata(L, this);
  66       lua_pushvalue(L, -2);
  67       lua_settable(L, functionTable);
  68       // registry this is associated to this function
  69       lqtL_passudata(L, this, "QObject*");
  70       lua_insert(L, -2);
  71       lua_pushvalue(L, -2);
  72       lua_settable(L, functionTable);
  73     } else {
  74       // leave the qobject on top;
  75       qDebug() << "Function" << this << "scheduled for deletion";
  76       this->deleteLater();
  77     }
  78     lua_replace(L, functionTable);
  79     lua_settop(L, functionTable);
  80   }
  81 ]]
  82 hpp.write[[
  83   virtual ~LuaFunction();
  84
  85   private:
  86     lua_State *L;
  87     static int __gc (lua_State *L);
  88   protected:
  89   public:
  90   public slots:
  91 ]]
  92 cpp.write[[
  93 LuaFunction::~LuaFunction() {
  94   qDebug() << "Function" << this << "is dead";
  95 }
  96 ]]
  97 --[[
  98 int LuaFunction::__gc (lua_State *L) {
  99   QPointer<QObject> *qp = (QPointer<QObject> *)lua_touserdata(L, 1);
 100   if (*qp) {
 101     (*qp)->deleteLater();
 102   }
 103     qDebug() << "LuaFunction" << *qp << "scheduled for deletion";
 104     return 0;
 105   }
 106 ]]
 107
 108 signatures = {
 109   [0] = {
 110     [''] = '',
 111   }
 112 }
 113
 114 for nargs = 1,ARG_MAX do
 115   signatures[nargs] = {}
 116   for oldsig, oldbody in pairs(signatures[nargs-1]) do
 117     for argtype, argpush in pairs(TYPES) do
 118       signatures[nargs][oldsig..((nargs==1) and '' or ', ')..argtype..' arg'..tostring(nargs)] = oldbody..argpush.."(L, arg"..tostring(nargs)..');'
 119     end
 120   end
 121 end
 122
 123 for i=0,ARG_MAX do
 124   for s, b in pairs(signatures[i]) do
 125     hpp.write('  void function ('..s..');\n')
 126     cpp.write'void LuaFunction::function ('
 127     cpp.write(s)
 128     cpp.write[[) {
 129   int functionTable = lua_gettop(L) + 1;
 130   lua_getfield(L, LUA_REGISTRYINDEX, LUA_FUNCTION_REGISTRY);
 131   if (!lua_istable(L, -1)) {
 132     return;
 133   }
 134   lua_pushlightuserdata(L, this);
 135   lua_gettable(L, functionTable);
 136   ]]
 137     cpp.write(b)
 138     cpp.write'\n  '
 139     cpp.write'lua_call(L,'
 140     cpp.write(tostring(i))
 141     cpp.write', 0);\n'
 142     cpp.write[[
 143 };]]
 144     cpp.write'\n'
 145   end
 146 end
 147
 148 hpp.write[[
 149 };
 150
 151
 152 ]]
 153
 154 hpp.write("#endif // "..HEADER_DEFINE.."\n")
 155
 156
 157 io.write(cpp.string)
 158