source: code/trunk/src/tolua/tolua_map.c @ 3003

/* tolua: functions to map features
** Support code for Lua bindings.
** Written by Waldemar Celes
** TeCGraf/PUC-Rio
** Apr 2003
** $Id: $
*/

/* This code is free software; you can redistribute it and/or modify it.
** The software provided hereunder is on an "as is" basis, and
** the author has no obligation to provide maintenance, support, updates,
** enhancements, or modifications.
*/

#include "tolua++.h"
#include "tolua_event.h"
#include "lauxlib.h"

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>


/* Create metatable
        * Create and register new metatable
*/
static int tolua_newmetatable (lua_State* L, char* name)
{
        int r = luaL_newmetatable(L,name);

        #ifdef LUA_VERSION_NUM /* only lua 5.1 */
        if (r) {
                lua_pushvalue(L, -1);
                lua_pushstring(L, name);
                lua_settable(L, LUA_REGISTRYINDEX); /* reg[mt] = type_name */
        };
        #endif

        if (r)
                tolua_classevents(L); /* set meta events */
        lua_pop(L,1);
        return r;
}

/* Map super classes
        * It sets 'name' as being also a 'base', mapping all super classes of 'base' in 'name'
*/
static void mapsuper (lua_State* L, const char* name, const char* base)
{
        /* push registry.super */
 lua_pushstring(L,"tolua_super");
 lua_rawget(L,LUA_REGISTRYINDEX);    /* stack: super */
        luaL_getmetatable(L,name);          /* stack: super mt */
 lua_rawget(L,-2);                   /* stack: super table */
        if (lua_isnil(L,-1))
        {
         /* create table */
                lua_pop(L,1);
         lua_newtable(L);                    /* stack: super table */
         luaL_getmetatable(L,name);          /* stack: super table mt */
                lua_pushvalue(L,-2);                /* stack: super table mt table */
                lua_rawset(L,-4);                   /* stack: super table */
        }

        /* set base as super class */
        lua_pushstring(L,base);
        lua_pushboolean(L,1);
        lua_rawset(L,-3);                    /* stack: super table */

        /* set all super class of base as super class of name */
        luaL_getmetatable(L,base);          /* stack: super table base_mt */
        lua_rawget(L,-3);                   /* stack: super table base_table */
        if (lua_istable(L,-1))
        {
                /* traverse base table */
                lua_pushnil(L);  /* first key */
                while (lua_next(L,-2) != 0)
                {
                        /* stack: ... base_table key value */
                        lua_pushvalue(L,-2);    /* stack: ... base_table key value key */
                        lua_insert(L,-2);       /* stack: ... base_table key key value */
                        lua_rawset(L,-5);       /* stack: ... base_table key */
                }
        }
        lua_pop(L,3);                       /* stack: <empty> */
}

/* creates a 'tolua_ubox' table for base clases, and
// expects the metatable and base metatable on the stack */
static void set_ubox(lua_State* L) {

        /* mt basemt */
        if (!lua_isnil(L, -1)) {
                lua_pushstring(L, "tolua_ubox");
                lua_rawget(L,-2);
        } else {
                lua_pushnil(L);
        };
        /* mt basemt base_ubox */
        if (!lua_isnil(L,-1)) {
                lua_pushstring(L, "tolua_ubox");
                lua_insert(L, -2);
                /* mt basemt key ubox */
                lua_rawset(L,-4);
                /* (mt with ubox) basemt */
        } else {
                /* mt basemt nil */
                lua_pop(L, 1);
                lua_pushstring(L,"tolua_ubox"); lua_newtable(L);
                /* make weak value metatable for ubox table to allow userdata to be
                garbage-collected */
                lua_newtable(L); lua_pushliteral(L, "__mode"); lua_pushliteral(L, "v"); lua_rawset(L, -3);               /* stack: string ubox mt */
                lua_setmetatable(L, -2);  /* stack:mt basemt string ubox */
                lua_rawset(L,-4);
        };

};

/* Map inheritance
        * It sets 'name' as derived from 'base' by setting 'base' as metatable of 'name'
*/
static void mapinheritance (lua_State* L, const char* name, const char* base)
{
        /* set metatable inheritance */
        luaL_getmetatable(L,name);

        if (base && *base)
                luaL_getmetatable(L,base);
        else {

                if (lua_getmetatable(L, -1)) { /* already has a mt, we don't overwrite it */
                        lua_pop(L, 2);
                        return;
                };
                luaL_getmetatable(L,"tolua_commonclass");
        };

        set_ubox(L);

        lua_setmetatable(L,-2);
        lua_pop(L,1);
}

/* Object type
*/
static int tolua_bnd_type (lua_State* L)
{
        tolua_typename(L,lua_gettop(L));
        return 1;
}

/* Take ownership
*/
static int tolua_bnd_takeownership (lua_State* L)
{
        int success = 0;
        if (lua_isuserdata(L,1))
        {
                if (lua_getmetatable(L,1))        /* if metatable? */
                {
                        lua_pop(L,1);             /* clear metatable off stack */
                        /* force garbage collection to avoid C to reuse a to-be-collected address */
                        #ifdef LUA_VERSION_NUM
                        lua_gc(L, LUA_GCCOLLECT, 0);
                        #else
                        lua_setgcthreshold(L,0);
                        #endif

                        success = tolua_register_gc(L,1);
                }
        }
        lua_pushboolean(L,success!=0);
        return 1;
}

/* Release ownership
*/
static int tolua_bnd_releaseownership (lua_State* L)
{
        int done = 0;
        if (lua_isuserdata(L,1))
        {
                void* u = *((void**)lua_touserdata(L,1));
                /* force garbage collection to avoid releasing a to-be-collected address */
                #ifdef LUA_VERSION_NUM
                lua_gc(L, LUA_GCCOLLECT, 0);
                #else
                lua_setgcthreshold(L,0);
                #endif
                lua_pushstring(L,"tolua_gc");
                lua_rawget(L,LUA_REGISTRYINDEX);
                lua_pushlightuserdata(L,u);
                lua_rawget(L,-2);
                lua_getmetatable(L,1);
                if (lua_rawequal(L,-1,-2))  /* check that we are releasing the correct type */
                {
                        lua_pushlightuserdata(L,u);
                        lua_pushnil(L);
                        lua_rawset(L,-5);
                        done = 1;
                }
        }
        lua_pushboolean(L,done!=0);
        return 1;
}

/* Type casting
*/
static int tolua_bnd_cast (lua_State* L)
{

/* // old code
        void* v = tolua_tousertype(L,1,NULL);
        const char* s = tolua_tostring(L,2,NULL);
        if (v && s)
         tolua_pushusertype(L,v,s);
        else
         lua_pushnil(L);
        return 1;
*/

        void* v;
        const char* s;
        if (lua_islightuserdata(L, 1)) {
                v = tolua_touserdata(L, 1, NULL);
        } else {
                v = tolua_tousertype(L, 1, 0);
        };

        s = tolua_tostring(L,2,NULL);
        if (v && s)
         tolua_pushusertype(L,v,s);
        else
         lua_pushnil(L);
        return 1;
}

/* Inheritance
*/
static int tolua_bnd_inherit (lua_State* L) {

        /* stack: lua object, c object */
        lua_pushstring(L, ".c_instance");
        lua_pushvalue(L, -2);
        lua_rawset(L, -4);
        /* l_obj[".c_instance"] = c_obj */

        return 0;
};

#ifdef LUA_VERSION_NUM /* lua 5.1 */
static int tolua_bnd_setpeer(lua_State* L) {

        /* stack: userdata, table */
        if (!lua_isuserdata(L, -2)) {
                lua_pushstring(L, "Invalid argument #1 to setpeer: userdata expected.");
                lua_error(L);
        };
        
        if (lua_isnil(L, -1)) {

                lua_pop(L, 1);
                lua_pushvalue(L, TOLUA_NOPEER);
        };
        lua_setfenv(L, -2);

        return 0;
};

static int tolua_bnd_getpeer(lua_State* L) {

        /* stack: userdata */
        lua_getfenv(L, -1);
        if (lua_rawequal(L, -1, TOLUA_NOPEER)) {
                lua_pop(L, 1);
                lua_pushnil(L);
        };
        return 1;
};
#endif

/* static int class_gc_event (lua_State* L); */

TOLUA_API void tolua_open (lua_State* L)
{
 int top = lua_gettop(L);
 lua_pushstring(L,"tolua_opened");
 lua_rawget(L,LUA_REGISTRYINDEX);
 if (!lua_isboolean(L,-1))
 {
  lua_pushstring(L,"tolua_opened"); lua_pushboolean(L,1); lua_rawset(L,LUA_REGISTRYINDEX);

  #ifndef LUA_VERSION_NUM /* only prior to lua 5.1 */
  /* create peer object table */
  lua_pushstring(L, "tolua_peers"); lua_newtable(L);
  /* make weak key metatable for peers indexed by userdata object */
  lua_newtable(L); lua_pushliteral(L, "__mode"); lua_pushliteral(L, "k"); lua_rawset(L, -3);                /* stack: string peers mt */
  lua_setmetatable(L, -2);   /* stack: string peers */
  lua_rawset(L,LUA_REGISTRYINDEX);
  #endif

  /* create object ptr -> udata mapping table */
  lua_pushstring(L,"tolua_ubox"); lua_newtable(L);
  /* make weak value metatable for ubox table to allow userdata to be
     garbage-collected */
  lua_newtable(L); lua_pushliteral(L, "__mode"); lua_pushliteral(L, "v"); lua_rawset(L, -3);               /* stack: string ubox mt */
  lua_setmetatable(L, -2);  /* stack: string ubox */
  lua_rawset(L,LUA_REGISTRYINDEX);

  lua_pushstring(L,"tolua_super"); lua_newtable(L); lua_rawset(L,LUA_REGISTRYINDEX);
  lua_pushstring(L,"tolua_gc"); lua_newtable(L);lua_rawset(L,LUA_REGISTRYINDEX);

  /* create gc_event closure */
  lua_pushstring(L, "tolua_gc_event");
  lua_pushstring(L, "tolua_gc");
  lua_rawget(L, LUA_REGISTRYINDEX);
  lua_pushstring(L, "tolua_super");
  lua_rawget(L, LUA_REGISTRYINDEX);
  lua_pushcclosure(L, class_gc_event, 2);
  lua_rawset(L, LUA_REGISTRYINDEX);

  tolua_newmetatable(L,"tolua_commonclass");

  tolua_module(L,NULL,0);
  tolua_beginmodule(L,NULL);
  tolua_module(L,"tolua",0);
  tolua_beginmodule(L,"tolua");
  tolua_function(L,"type",tolua_bnd_type);
  tolua_function(L,"takeownership",tolua_bnd_takeownership);
  tolua_function(L,"releaseownership",tolua_bnd_releaseownership);
  tolua_function(L,"cast",tolua_bnd_cast);
  tolua_function(L,"inherit", tolua_bnd_inherit);
  #ifdef LUA_VERSION_NUM /* lua 5.1 */
  tolua_function(L, "setpeer", tolua_bnd_setpeer);
  tolua_function(L, "getpeer", tolua_bnd_getpeer);
  #endif

  tolua_endmodule(L);
  tolua_endmodule(L);
 }
 lua_settop(L,top);
}

/* Copy a C object
*/
TOLUA_API void* tolua_copy (lua_State* L, void* value, unsigned int size)
{
        void* clone = (void*)malloc(size);
        if (clone)
         memcpy(clone,value,size);
        else
                tolua_error(L,"insuficient memory",NULL);
        return clone;
}

/* Default collect function
*/
TOLUA_API int tolua_default_collect (lua_State* tolua_S)
{
 void* self = tolua_tousertype(tolua_S,1,0);
 free(self);
 return 0;
}

/* Do clone
*/
TOLUA_API int tolua_register_gc (lua_State* L, int lo)
{
 int success = 1;
 void *value = *(void **)lua_touserdata(L,lo);
 lua_pushstring(L,"tolua_gc");
 lua_rawget(L,LUA_REGISTRYINDEX);
        lua_pushlightuserdata(L,value);
        lua_rawget(L,-2);
        if (!lua_isnil(L,-1)) /* make sure that object is not already owned */
                success = 0;
        else
        {
                lua_pushlightuserdata(L,value);
                lua_getmetatable(L,lo);
                lua_rawset(L,-4);
        }
        lua_pop(L,2);
        return success;
}

/* Register a usertype
        * It creates the correspoding metatable in the registry, for both 'type' and 'const type'.
        * It maps 'const type' as being also a 'type'
*/
TOLUA_API void tolua_usertype (lua_State* L, char* type)
{
 char ctype[128] = "const ";
 strncat(ctype,type,120);

        /* create both metatables */
 if (tolua_newmetatable(L,ctype) && tolua_newmetatable(L,type))
         mapsuper(L,type,ctype);             /* 'type' is also a 'const type' */
}


/* Begin module
        * It pushes the module (or class) table on the stack
*/
TOLUA_API void tolua_beginmodule (lua_State* L, char* name)
{
        if (name)
        {
         lua_pushstring(L,name);
                lua_rawget(L,-2);
        }
        else
         lua_pushvalue(L,LUA_GLOBALSINDEX);
}

/* End module
        * It pops the module (or class) from the stack
*/
TOLUA_API void tolua_endmodule (lua_State* L)
{
        lua_pop(L,1);
}

/* Map module
        * It creates a new module
*/
#if 1
TOLUA_API void tolua_module (lua_State* L, char* name, int hasvar)
{
        if (name)
        {
                /* tolua module */
                lua_pushstring(L,name);
                lua_rawget(L,-2);
                if (!lua_istable(L,-1))  /* check if module already exists */
                {
                        lua_pop(L,1);
                 lua_newtable(L);
                 lua_pushstring(L,name);
                        lua_pushvalue(L,-2);
                 lua_rawset(L,-4);       /* assing module into module */
                }
        }
        else
        {
                /* global table */
                lua_pushvalue(L,LUA_GLOBALSINDEX);
        }
        if (hasvar)
        {
                if (!tolua_ismodulemetatable(L))  /* check if it already has a module metatable */
                {
                        /* create metatable to get/set C/C++ variable */
                        lua_newtable(L);
                        tolua_moduleevents(L);
                        if (lua_getmetatable(L,-2))
                                lua_setmetatable(L,-2);  /* set old metatable as metatable of metatable */
                        lua_setmetatable(L,-2);
                }
        }
        lua_pop(L,1);               /* pop module */
}
#else
TOLUA_API void tolua_module (lua_State* L, char* name, int hasvar)
{
        if (name)
        {
                /* tolua module */
                lua_pushstring(L,name);
                lua_newtable(L);
        }
        else
        {
                /* global table */
                lua_pushvalue(L,LUA_GLOBALSINDEX);
        }
        if (hasvar)
        {
                /* create metatable to get/set C/C++ variable */
                lua_newtable(L);
                tolua_moduleevents(L);
                if (lua_getmetatable(L,-2))
                        lua_setmetatable(L,-2);  /* set old metatable as metatable of metatable */
                lua_setmetatable(L,-2);
        }
        if (name)
                lua_rawset(L,-3);       /* assing module into module */
        else
                lua_pop(L,1);           /* pop global table */
}
#endif

static void push_collector(lua_State* L, const char* type, lua_CFunction col) {

        /* push collector function, but only if it's not NULL, or if there's no
           collector already */
        if (!col) return;
        luaL_getmetatable(L,type);
        lua_pushstring(L,".collector");
        /*
        if (!col) {
                lua_pushvalue(L, -1);
                lua_rawget(L, -3);
                if (!lua_isnil(L, -1)) {
                        lua_pop(L, 3);
                        return;
                };
                lua_pop(L, 1);
        };
        //      */
        lua_pushcfunction(L,col);

        lua_rawset(L,-3);
        lua_pop(L, 1);
};

/* Map C class
        * It maps a C class, setting the appropriate inheritance and super classes.
*/
TOLUA_API void tolua_cclass (lua_State* L, char* lname, char* name, char* base, lua_CFunction col)
{
        char cname[128] = "const ";
        char cbase[128] = "const ";
        strncat(cname,name,120);
        strncat(cbase,base,120);

        mapinheritance(L,name,base);
        mapinheritance(L,cname,name);

        mapsuper(L,cname,cbase);
        mapsuper(L,name,base);

        lua_pushstring(L,lname);
        
        push_collector(L, name, col);
        /*
        luaL_getmetatable(L,name);
        lua_pushstring(L,".collector");
        lua_pushcfunction(L,col);

        lua_rawset(L,-3);
        */
        
        luaL_getmetatable(L,name);
        lua_rawset(L,-3);              /* assign class metatable to module */

        /* now we also need to store the collector table for the const
           instances of the class */
        push_collector(L, cname, col);
        /*
        luaL_getmetatable(L,cname);
        lua_pushstring(L,".collector");
        lua_pushcfunction(L,col);
        lua_rawset(L,-3);
        lua_pop(L,1);
        */
        

}

/* Add base
        * It adds additional base classes to a class (for multiple inheritance)
        * (not for now)
TOLUA_API void tolua_addbase(lua_State* L, char* name, char* base) {

        char cname[128] = "const ";
        char cbase[128] = "const ";
        strncat(cname,name,120);
        strncat(cbase,base,120);

        mapsuper(L,cname,cbase);
        mapsuper(L,name,base);
};
*/

/* Map function
        * It assigns a function into the current module (or class)
*/
TOLUA_API void tolua_function (lua_State* L, char* name, lua_CFunction func)
{
 lua_pushstring(L,name);
 lua_pushcfunction(L,func);
        lua_rawset(L,-3);
}

/* sets the __call event for the class (expects the class' main table on top) */
/*      never really worked :(
TOLUA_API void tolua_set_call_event(lua_State* L, lua_CFunction func, char* type) {

        lua_getmetatable(L, -1);
        //luaL_getmetatable(L, type);
        lua_pushstring(L,"__call");
        lua_pushcfunction(L,func);
        lua_rawset(L,-3);
        lua_pop(L, 1);
};
*/

/* Map constant number
        * It assigns a constant number into the current module (or class)
*/
TOLUA_API void tolua_constant (lua_State* L, char* name, double value)
{
        lua_pushstring(L,name);
        tolua_pushnumber(L,value);
        lua_rawset(L,-3);
}


/* Map variable
        * It assigns a variable into the current module (or class)
*/
TOLUA_API void tolua_variable (lua_State* L, char* name, lua_CFunction get, lua_CFunction set)
{
        /* get func */
        lua_pushstring(L,".get");
        lua_rawget(L,-2);
        if (!lua_istable(L,-1))
        {
                /* create .get table, leaving it at the top */
                lua_pop(L,1);
                lua_newtable(L);
         lua_pushstring(L,".get");
                lua_pushvalue(L,-2);
                lua_rawset(L,-4);
        }
        lua_pushstring(L,name);
        lua_pushcfunction(L,get);
 lua_rawset(L,-3);                  /* store variable */
        lua_pop(L,1);                      /* pop .get table */

        /* set func */
        if (set)
        {
                lua_pushstring(L,".set");
                lua_rawget(L,-2);
                if (!lua_istable(L,-1))
                {
                        /* create .set table, leaving it at the top */
                        lua_pop(L,1);
                        lua_newtable(L);
                        lua_pushstring(L,".set");
                        lua_pushvalue(L,-2);
                        lua_rawset(L,-4);
                }
                lua_pushstring(L,name);
                lua_pushcfunction(L,set);
                lua_rawset(L,-3);                  /* store variable */
                lua_pop(L,1);                      /* pop .set table */
        }
}

/* Access const array
        * It reports an error when trying to write into a const array
*/
static int const_array (lua_State* L)
{
 luaL_error(L,"value of const array cannot be changed");
 return 0;
}

/* Map an array
        * It assigns an array into the current module (or class)
*/
TOLUA_API void tolua_array (lua_State* L, char* name, lua_CFunction get, lua_CFunction set)
{
        lua_pushstring(L,".get");
        lua_rawget(L,-2);
        if (!lua_istable(L,-1))
        {
                /* create .get table, leaving it at the top */
                lua_pop(L,1);
                lua_newtable(L);
         lua_pushstring(L,".get");
                lua_pushvalue(L,-2);
                lua_rawset(L,-4);
        }
        lua_pushstring(L,name);

 lua_newtable(L);           /* create array metatable */
 lua_pushvalue(L,-1);
        lua_setmetatable(L,-2);    /* set the own table as metatable (for modules) */
 lua_pushstring(L,"__index");
 lua_pushcfunction(L,get);
        lua_rawset(L,-3);
 lua_pushstring(L,"__newindex");
 lua_pushcfunction(L,set?set:const_array);
        lua_rawset(L,-3);

 lua_rawset(L,-3);                  /* store variable */
        lua_pop(L,1);                      /* pop .get table */
}


TOLUA_API void tolua_dobuffer(lua_State* L, char* B, unsigned int size, const char* name) {

 #ifdef LUA_VERSION_NUM /* lua 5.1 */
 luaL_loadbuffer(L, B, size, name) || lua_pcall(L, 0, 0, 0);
 #else
 lua_dobuffer(L, B, size, name);
 #endif
};