integration/luprex/core/cpp/luasnap.hpp

/////////////////////////////////////////////////////////////////////////////
//
// LUASNAP
//
// A lua interpreter that can be checkpointed (snapshotted). This makes it
// possible to roll the entire interpreter back to a previously-snapshotted
// state.
//
// To accomplish this, we use eris serialization.  This is messy and not
// very modular, but it does work.
//
/////////////////////////////////////////////////////////////////////////////

#ifndef LUASNAP_HPP
#define LUASNAP_HPP

#include "StreamBuffer.hpp"
#include "luastack.hpp"

class LuaSnap {
private:
    lua_State *state_;
    StreamBuffer snapshot_;
    
public:
    LuaSnap();
    ~LuaSnap();

    // Get the lua intepreter.
    //
    lua_State *state() const { return state_; }

    // Serialize the state of the lua interpreter.
    //
    void serialize(StreamBuffer *sb);
    
    // Restore the the lua interpreter given a serialized state.
    //
    void deserialize(StreamBuffer *sb);

    // Return true if there's a saved snapshot.
    //
    bool have_snapshot() const;

    // snapshot the state of the lua interpreter.
    //
    // If there is already a snapshot, this panics.
    //
    void snapshot();

    // Rollback the lua intepreter to the snapshotted state.
    //
    // If there is no snapshot, this panics.
    //
    void rollback();
};


#endif // LUASNAP_HPP