61 lines
1.5 KiB
C++
61 lines
1.5 KiB
C++
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////////////////////////////////////////////////////////////
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//
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// LUASNAP
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//
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// A lua interpreter that can be checkpointed (snapshotted).
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// This makes it possible to roll the entire interpreter back
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// to a previously-snapshotted state.
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//
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// To accomplish this, we take advantage of the 'allocf' parameter
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// to lua_newstate. This lets us hook the lua allocator, which
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// in turn lets us find every block of memory currently in use by
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// lua. To snapshot, we 'memcpy' every block of memory
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// that lua is using into a buffer. To rollback, we just 'memcpy'
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// the data back.
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//
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// The current implementation is a proof-of-concept. It's quite
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// wasteful of memory, roughly doubling the amount of RAM that
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// LUA uses. But it does demonstrate that this method of snapshot
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// and rollback is feasible.
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//
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////////////////////////////////////////////////////////////
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#ifndef LUASNAP_HPP
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#define LUASNAP_HPP
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#include "luastack.hpp"
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class LuaSnapData;
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class LuaSnap {
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private:
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lua_State *state_;
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LuaSnapData *data_;
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public:
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LuaSnap();
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~LuaSnap();
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// Get the lua intepreter.
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//
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lua_State *state() const { return state_; }
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// Return true if there's a saved snapshot.
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//
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bool have_snapshot() const;
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// snapshot the state of the lua interpreter.
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//
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// If there is already a snapshot, this panics.
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//
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void snapshot();
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// Rollback the lua intepreter to the snapshotted state.
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//
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// If there is no snapshot, this panics.
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//
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void rollback();
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};
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#endif // LUASNAP_HPP
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