gluon/package/gluon-core/src/site.c

#include "libgluonutil.h"
#include "lua-jsonc.h"

#include <limits.h>
#include <lualib.h>
#include <lauxlib.h>


#define UDATA "gluon.site"


static struct json_object * gluon_site_udata(lua_State *L, int narg) {
        return *(struct json_object **)luaL_checkudata(L, narg, UDATA);
}

static void gluon_site_push_none(lua_State *L) {
        lua_pushlightuserdata(L, gluon_site_push_none);
        lua_rawget(L, LUA_REGISTRYINDEX);
}

static void gluon_site_do_wrap(lua_State *L, struct json_object *obj) {
        struct json_object **objp = lua_newuserdata(L, sizeof(struct json_object *));
        *objp = json_object_get(obj);
        luaL_getmetatable(L, UDATA);
        lua_setmetatable(L, -2);
}

static void gluon_site_wrap(lua_State *L, struct json_object *obj) {
        if (obj)
                gluon_site_do_wrap(L, obj);
        else
                gluon_site_push_none(L);
}


static int gluon_site_index(lua_State *L) {
        struct json_object *obj = gluon_site_udata(L, 1);
        const char *key;
        lua_Number lua_index;
        size_t index;
        struct json_object *v = NULL;

        switch (json_object_get_type(obj)) {
	case json_type_object:
                key = lua_tostring(L, 2);
                if (key)
                        json_object_object_get_ex(obj, key, &v);
                break;

	case json_type_array:
                index = lua_index = lua_tonumber(L, 2);
                if (lua_index == (lua_Number)index && index >= 1)
                        v = json_object_array_get_idx(obj, index-1);
                break;

	case json_type_string:
        case json_type_null:
                break;

	case json_type_boolean:
	case json_type_int:
	case json_type_double:
                luaL_error(L, "attempt to index a number or boolean value");
                __builtin_unreachable();
        }

        gluon_site_wrap(L, v);
        return 1;
}

static int gluon_site_call(lua_State *L) {
        struct json_object *obj = gluon_site_udata(L, 1);

        if (obj) {
                lua_jsonc_push_json(L, obj);
        } else {
                if (lua_isnone(L, 2))
                        lua_pushnil(L);
                else
                        lua_pushvalue(L, 2);
        }

        return 1;
}

static int gluon_site_gc(lua_State *L) {
        json_object_put(gluon_site_udata(L, 1));
        return 0;
}

static const luaL_reg R[] = {
        { "__index", gluon_site_index },
        { "__call", gluon_site_call },
        { "__gc", gluon_site_gc },
        {}
};

int luaopen_gluon_site(lua_State *L) {
        luaL_newmetatable(L, UDATA);
        luaL_register(L, NULL, R);
        lua_pop(L, 1);

        /* Create "none" object */
        lua_pushlightuserdata(L, gluon_site_push_none);
        gluon_site_do_wrap(L, NULL);
        lua_rawset(L, LUA_REGISTRYINDEX);

        struct json_object *site = gluonutil_load_site_config();
        gluon_site_wrap(L, site);
        json_object_put(site);

	return 1;
}