interpreter.cpp

lua cpp 能和c++很好结合的一种脚本语言 体积小速度快

#include "Interpreter.hpp"

namespace lua
{

OPT_INLINE
Interpreter::Interpreter(LuaLib whichLibs): m_vm(lua_open()) 
{
    if (m_vm == NULL)
        throw std::runtime_error("Could not initialize LUA interpreter");
        
    #if HAVE_LUA51
    if (whichLibs == LIB_ALL)
        luaL_openlibs(m_vm);
    else
    #endif
    {
        if (whichLibs & LIB_BASE)   luaopen_base(m_vm);
        #if HAVE_LUA51
        if (whichLibs & LIB_PACKAGE)luaopen_package(m_vm);
        #endif
        if (whichLibs & LIB_IO)     luaopen_io(m_vm);
        if (whichLibs & LIB_STRING) luaopen_string(m_vm);
        if (whichLibs & LIB_MATH)   luaopen_math(m_vm);
        if (whichLibs & LIB_TABLE)  luaopen_table(m_vm);
        if (whichLibs & LIB_DEBUG)  luaopen_debug(m_vm);
    }
}
    

OPT_INLINE
/// Execute a file in protected mode
void Interpreter::doFile(const std::string& filename) 
{
    checkOk( luaL_loadfile(m_vm, filename.c_str()), 
             "Error interpreting file" );
             
    const int nargs = 0, errFnIdx = 0;
    checkOk( lua_pcall(m_vm, nargs, LUA_MULTRET, errFnIdx), 
             "Error running script" );
}


OPT_INLINE
/// Execute a string in protected mode
void Interpreter::doString(const std::string& cmd) 
{
    //lua_dostring(m_vm, cmd.c_str()); // deprecated
    checkOk( luaL_loadbuffer(m_vm, cmd.c_str(), cmd.size(), cmd.c_str()), 
             "Error interpreting string" );
    
    const int nargs = 0, errFnIdx = 0;
    checkOk( lua_pcall(m_vm, nargs, LUA_MULTRET, errFnIdx), 
             "Error running string" );
}
    
    
OPT_INLINE
/** Adapted from lua auxlib. If the status indicates an error, the error message
    is saved (get with errMsg()), and if a lua function refered by global _ALERT
    variable is defined, just call it; otherwise throw a std::runtime exception 
    containing the error message. 
    */
void Interpreter::checkOk(int status, const char* msg)
{
    if (status != ERR_NONE)
    {
        m_errMsg = lua_tostring(m_vm, -1);
        lua_getglobal(m_vm, "_ALERT");
        if (lua_isfunction(m_vm, -1)) 
        {
            lua_insert(m_vm, -2);
            lua_call(m_vm, 1, 0);
        }
        else // no _ALERT function; throw exception
        {  
            lua_pop(m_vm, 2);  // remove error message and _ALERT 
            throw std::runtime_error(msg);
        }
    }
}

} // namespace