order 3lp dirs
This commit is contained in:
829
3rd/LuaBridge/detail/Userdata.h
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829
3rd/LuaBridge/detail/Userdata.h
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@@ -0,0 +1,829 @@
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//------------------------------------------------------------------------------
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/*
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https://github.com/vinniefalco/LuaBridge
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Copyright 2019, Dmitry Tarakanov
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Copyright 2012, Vinnie Falco <vinnie.falco@gmail.com>
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||||
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License: The MIT License (http://www.opensource.org/licenses/mit-license.php)
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||||
|
||||
Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
of this software and associated documentation files (the "Software"), to deal
|
||||
in the Software without restriction, including without limitation the rights
|
||||
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
copies of the Software, and to permit persons to whom the Software is
|
||||
furnished to do so, subject to the following conditions:
|
||||
|
||||
The above copyright notice and this permission notice shall be included in all
|
||||
copies or substantial portions of the Software.
|
||||
|
||||
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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||||
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||||
SOFTWARE.
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*/
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//==============================================================================
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#pragma once
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#include <LuaBridge/detail/ClassInfo.h>
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#include <cassert>
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#include <stdexcept>
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||||
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namespace luabridge {
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//==============================================================================
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/**
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Return the identity pointer for our lightuserdata tokens.
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||||
Because of Lua's dynamic typing and our improvised system of imposing C++
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class structure, there is the possibility that executing scripts may
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knowingly or unknowingly cause invalid data to get passed to the C functions
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||||
created by LuaBridge. In particular, our security model addresses the
|
||||
following:
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1. Scripts cannot create a userdata (ignoring the debug lib).
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2. Scripts cannot create a lightuserdata (ignoring the debug lib).
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3. Scripts cannot set the metatable on a userdata.
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*/
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/**
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Interface to a class pointer retrievable from a userdata.
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*/
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class Userdata
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{
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protected:
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void* m_p; // subclasses must set this
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||||
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Userdata() : m_p (0)
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||||
{
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}
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||||
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||||
//--------------------------------------------------------------------------
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/**
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Get an untyped pointer to the contained class.
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*/
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void* getPointer ()
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||||
{
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return m_p;
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}
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private:
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||||
//--------------------------------------------------------------------------
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/**
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||||
Validate and retrieve a Userdata on the stack.
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||||
|
||||
The Userdata must exactly match the corresponding class table or
|
||||
const table, or else a Lua error is raised. This is used for the
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||||
__gc metamethod.
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*/
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static Userdata* getExactClass (lua_State* L, int index, void const* /*classKey*/)
|
||||
{
|
||||
return static_cast <Userdata*> (lua_touserdata (L, lua_absindex (L, index)));
|
||||
}
|
||||
|
||||
//--------------------------------------------------------------------------
|
||||
/**
|
||||
Validate and retrieve a Userdata on the stack.
|
||||
|
||||
The Userdata must be derived from or the same as the given base class,
|
||||
identified by the key. If canBeConst is false, generates an error if
|
||||
the resulting Userdata represents to a const object. We do the type check
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first so that the error message is informative.
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*/
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static Userdata* getClass (lua_State* L,
|
||||
int index,
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void const* registryConstKey,
|
||||
void const* registryClassKey,
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||||
bool canBeConst)
|
||||
{
|
||||
index = lua_absindex (L, index);
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||||
|
||||
lua_getmetatable (L, index); // Stack: object metatable (ot) | nil
|
||||
if (!lua_istable (L, -1))
|
||||
{
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, registryClassKey); // Stack: registry metatable (rt) | nil
|
||||
return throwBadArg (L, index);
|
||||
}
|
||||
|
||||
lua_rawgetp (L, -1, getConstKey ()); // Stack: ot | nil, const table (co) | nil
|
||||
assert (lua_istable (L, -1) || lua_isnil (L, -1));
|
||||
|
||||
// If const table is NOT present, object is const. Use non-const registry table
|
||||
// if object cannot be const, so constness validation is done automatically.
|
||||
// E.g. nonConstFn (constObj)
|
||||
// -> canBeConst = false, isConst = true
|
||||
// -> 'Class' registry table, 'const Class' object table
|
||||
// -> 'expected Class, got const Class'
|
||||
bool isConst = lua_isnil (L, -1); // Stack: ot | nil, nil, rt
|
||||
if (isConst && canBeConst)
|
||||
{
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, registryConstKey); // Stack: ot, nil, rt
|
||||
}
|
||||
else
|
||||
{
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, registryClassKey); // Stack: ot, co, rt
|
||||
}
|
||||
|
||||
lua_insert (L, -3); // Stack: rt, ot, co | nil
|
||||
lua_pop (L, 1); // Stack: rt, ot
|
||||
|
||||
for (;;)
|
||||
{
|
||||
if (lua_rawequal (L, -1, -2)) // Stack: rt, ot
|
||||
{
|
||||
lua_pop (L, 2); // Stack: -
|
||||
return static_cast <Userdata*> (lua_touserdata (L, index));
|
||||
}
|
||||
|
||||
// Replace current metatable with it's base class.
|
||||
lua_rawgetp (L, -1, getParentKey ()); // Stack: rt, ot, parent ot (pot) | nil
|
||||
|
||||
if (lua_isnil (L, -1)) // Stack: rt, ot, nil
|
||||
{
|
||||
// Drop the object metatable because it may be some parent metatable
|
||||
lua_pop (L, 2); // Stack: rt
|
||||
return throwBadArg (L, index);
|
||||
}
|
||||
|
||||
lua_remove (L, -2); // Stack: rt, pot
|
||||
}
|
||||
|
||||
// no return
|
||||
}
|
||||
|
||||
static bool isInstance (lua_State* L, int index, void const* registryClassKey)
|
||||
{
|
||||
index = lua_absindex (L, index);
|
||||
|
||||
int result = lua_getmetatable (L, index); // Stack: object metatable (ot) | nothing
|
||||
if (result == 0)
|
||||
{
|
||||
return false; // Nothing was pushed on the stack
|
||||
}
|
||||
if (!lua_istable (L, -1))
|
||||
{
|
||||
lua_pop (L, 1); // Stack: -
|
||||
return false;
|
||||
}
|
||||
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, registryClassKey); // Stack: ot, rt
|
||||
lua_insert (L, -2); // Stack: rt, ot
|
||||
|
||||
for (;;)
|
||||
{
|
||||
if (lua_rawequal (L, -1, -2)) // Stack: rt, ot
|
||||
{
|
||||
lua_pop (L, 2); // Stack: -
|
||||
return true;
|
||||
}
|
||||
|
||||
// Replace current metatable with it's base class.
|
||||
lua_rawgetp (L, -1, getParentKey ()); // Stack: rt, ot, parent ot (pot) | nil
|
||||
|
||||
if (lua_isnil (L, -1)) // Stack: rt, ot, nil
|
||||
{
|
||||
lua_pop (L, 3); // Stack: -
|
||||
return false;
|
||||
}
|
||||
|
||||
lua_remove (L, -2); // Stack: rt, pot
|
||||
}
|
||||
}
|
||||
|
||||
static Userdata* throwBadArg (lua_State* L, int index)
|
||||
{
|
||||
assert (lua_istable (L, -1) || lua_isnil (L, -1)); // Stack: rt | nil
|
||||
|
||||
const char* expected = 0;
|
||||
if (lua_isnil (L, -1)) // Stack: nil
|
||||
{
|
||||
expected = "unregistered class";
|
||||
}
|
||||
else
|
||||
{
|
||||
lua_rawgetp (L, -1, getTypeKey ()); // Stack: rt, registry type
|
||||
expected = lua_tostring (L, -1);
|
||||
}
|
||||
|
||||
const char* got = 0;
|
||||
if (lua_isuserdata (L, index))
|
||||
{
|
||||
lua_getmetatable (L, index); // Stack: ..., ot | nil
|
||||
if (lua_istable (L, -1)) // Stack: ..., ot
|
||||
{
|
||||
lua_rawgetp (L, -1, getTypeKey ()); // Stack: ..., ot, object type | nil
|
||||
if (lua_isstring (L, -1))
|
||||
{
|
||||
got = lua_tostring (L, -1);
|
||||
}
|
||||
}
|
||||
}
|
||||
if (!got)
|
||||
{
|
||||
got = lua_typename (L, lua_type (L, index));
|
||||
}
|
||||
|
||||
luaL_argerror (L, index, lua_pushfstring (L, "%s expected, got %s", expected, got));
|
||||
return 0;
|
||||
}
|
||||
|
||||
public:
|
||||
virtual ~Userdata () { }
|
||||
|
||||
//--------------------------------------------------------------------------
|
||||
/**
|
||||
Returns the Userdata* if the class on the Lua stack matches.
|
||||
|
||||
If the class does not match, a Lua error is raised.
|
||||
*/
|
||||
template <class T>
|
||||
static Userdata* getExact (lua_State* L, int index)
|
||||
{
|
||||
return getExactClass (L, index, ClassInfo <T>::getClassKey ());
|
||||
}
|
||||
|
||||
//--------------------------------------------------------------------------
|
||||
/**
|
||||
Get a pointer to the class from the Lua stack.
|
||||
|
||||
If the object is not the class or a subclass, or it violates the
|
||||
const-ness, a Lua error is raised.
|
||||
*/
|
||||
template <class T>
|
||||
static T* get (lua_State* L, int index, bool canBeConst)
|
||||
{
|
||||
if (lua_isnil (L, index))
|
||||
return 0;
|
||||
|
||||
return static_cast <T*> (getClass (
|
||||
L, index, ClassInfo <T>::getConstKey (),
|
||||
ClassInfo <T>::getClassKey (),
|
||||
canBeConst)->getPointer ());
|
||||
}
|
||||
|
||||
template <class T>
|
||||
static bool isInstance (lua_State* L, int index)
|
||||
{
|
||||
return isInstance (L, index, ClassInfo <T>::getClassKey ());
|
||||
}
|
||||
};
|
||||
|
||||
//----------------------------------------------------------------------------
|
||||
/**
|
||||
Wraps a class object stored in a Lua userdata.
|
||||
|
||||
The lifetime of the object is managed by Lua. The object is constructed
|
||||
inside the userdata using placement new.
|
||||
*/
|
||||
template <class T>
|
||||
class UserdataValue : public Userdata
|
||||
{
|
||||
private:
|
||||
UserdataValue <T> (UserdataValue <T> const&);
|
||||
UserdataValue <T> operator= (UserdataValue <T> const&);
|
||||
|
||||
char m_storage [sizeof (T)];
|
||||
|
||||
private:
|
||||
/**
|
||||
Used for placement construction.
|
||||
*/
|
||||
UserdataValue ()
|
||||
{
|
||||
m_p = 0;
|
||||
}
|
||||
|
||||
~UserdataValue ()
|
||||
{
|
||||
if (getPointer () != 0)
|
||||
{
|
||||
getObject ()->~T ();
|
||||
}
|
||||
}
|
||||
|
||||
public:
|
||||
/**
|
||||
Push a T via placement new.
|
||||
|
||||
The caller is responsible for calling placement new using the
|
||||
returned uninitialized storage.
|
||||
*/
|
||||
static UserdataValue <T>* place (lua_State* const L)
|
||||
{
|
||||
UserdataValue <T>* const ud = new (
|
||||
lua_newuserdata (L, sizeof (UserdataValue <T>))) UserdataValue <T> ();
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, ClassInfo <T>::getClassKey ());
|
||||
if (!lua_istable (L, -1))
|
||||
{
|
||||
throw std::logic_error ("The class is not registered in LuaBridge");
|
||||
}
|
||||
lua_setmetatable (L, -2);
|
||||
return ud;
|
||||
}
|
||||
|
||||
/**
|
||||
Push T via copy construction from U.
|
||||
*/
|
||||
template <class U>
|
||||
static inline void push (lua_State* const L, U const& u)
|
||||
{
|
||||
UserdataValue <T>* ud = place (L);
|
||||
new (ud->getObject ()) U (u);
|
||||
ud->commit ();
|
||||
}
|
||||
|
||||
/**
|
||||
Confirm object construction.
|
||||
*/
|
||||
void commit ()
|
||||
{
|
||||
m_p = getObject ();
|
||||
}
|
||||
|
||||
T* getObject ()
|
||||
{
|
||||
// If this fails to compile it means you forgot to provide
|
||||
// a Container specialization for your container!
|
||||
//
|
||||
return reinterpret_cast <T*> (&m_storage [0]);
|
||||
}
|
||||
};
|
||||
|
||||
//----------------------------------------------------------------------------
|
||||
/**
|
||||
Wraps a pointer to a class object inside a Lua userdata.
|
||||
|
||||
The lifetime of the object is managed by C++.
|
||||
*/
|
||||
class UserdataPtr : public Userdata
|
||||
{
|
||||
private:
|
||||
UserdataPtr (UserdataPtr const&);
|
||||
UserdataPtr operator= (UserdataPtr const&);
|
||||
|
||||
private:
|
||||
/** Push a pointer to object using metatable key.
|
||||
*/
|
||||
static void push (lua_State* L, const void* p, void const* const key)
|
||||
{
|
||||
new (lua_newuserdata (L, sizeof (UserdataPtr))) UserdataPtr (const_cast <void*> (p));
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, key);
|
||||
if (!lua_istable (L, -1))
|
||||
{
|
||||
throw std::logic_error ("The class is not registered in LuaBridge");
|
||||
}
|
||||
lua_setmetatable (L, -2);
|
||||
}
|
||||
|
||||
explicit UserdataPtr (void* const p)
|
||||
{
|
||||
m_p = p;
|
||||
|
||||
// Can't construct with a null pointer!
|
||||
//
|
||||
assert (m_p != 0);
|
||||
}
|
||||
|
||||
public:
|
||||
/** Push non-const pointer to object.
|
||||
*/
|
||||
template <class T>
|
||||
static void push (lua_State* const L, T* const p)
|
||||
{
|
||||
if (p)
|
||||
push (L, p, ClassInfo <T>::getClassKey ());
|
||||
else
|
||||
lua_pushnil (L);
|
||||
}
|
||||
|
||||
/** Push const pointer to object.
|
||||
*/
|
||||
template <class T>
|
||||
static void push (lua_State* const L, T const* const p)
|
||||
{
|
||||
if (p)
|
||||
push (L, p, ClassInfo <T>::getConstKey ());
|
||||
else
|
||||
lua_pushnil (L);
|
||||
}
|
||||
};
|
||||
|
||||
//============================================================================
|
||||
/**
|
||||
Wraps a container that references a class object.
|
||||
|
||||
The template argument C is the container type, ContainerTraits must be
|
||||
specialized on C or else a compile error will result.
|
||||
*/
|
||||
template <class C>
|
||||
class UserdataShared : public Userdata
|
||||
{
|
||||
private:
|
||||
UserdataShared (UserdataShared <C> const&);
|
||||
UserdataShared <C>& operator= (UserdataShared <C> const&);
|
||||
|
||||
typedef typename TypeTraits::removeConst <
|
||||
typename ContainerTraits <C>::Type>::Type T;
|
||||
|
||||
C m_c;
|
||||
|
||||
private:
|
||||
~UserdataShared ()
|
||||
{
|
||||
}
|
||||
|
||||
public:
|
||||
/**
|
||||
Construct from a container to the class or a derived class.
|
||||
*/
|
||||
template <class U>
|
||||
explicit UserdataShared (U const& u) : m_c (u)
|
||||
{
|
||||
m_p = const_cast <void*> (reinterpret_cast <void const*> (
|
||||
(ContainerTraits <C>::get (m_c))));
|
||||
}
|
||||
|
||||
/**
|
||||
Construct from a pointer to the class or a derived class.
|
||||
*/
|
||||
template <class U>
|
||||
explicit UserdataShared (U* u) : m_c (u)
|
||||
{
|
||||
m_p = const_cast <void*> (reinterpret_cast <void const*> (
|
||||
(ContainerTraits <C>::get (m_c))));
|
||||
}
|
||||
};
|
||||
|
||||
//----------------------------------------------------------------------------
|
||||
//
|
||||
// SFINAE helpers.
|
||||
//
|
||||
|
||||
// non-const objects
|
||||
template <class C, bool makeObjectConst>
|
||||
struct UserdataSharedHelper
|
||||
{
|
||||
typedef typename TypeTraits::removeConst <
|
||||
typename ContainerTraits <C>::Type>::Type T;
|
||||
|
||||
static void push (lua_State* L, C const& c)
|
||||
{
|
||||
if (ContainerTraits <C>::get (c) != 0)
|
||||
{
|
||||
new (lua_newuserdata (L, sizeof (UserdataShared <C>))) UserdataShared <C> (c);
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, ClassInfo <T>::getClassKey ());
|
||||
// If this goes off it means the class T is unregistered!
|
||||
assert (lua_istable (L, -1));
|
||||
lua_setmetatable (L, -2);
|
||||
}
|
||||
else
|
||||
{
|
||||
lua_pushnil (L);
|
||||
}
|
||||
}
|
||||
|
||||
static void push (lua_State* L, T* const t)
|
||||
{
|
||||
if (t)
|
||||
{
|
||||
new (lua_newuserdata (L, sizeof (UserdataShared <C>))) UserdataShared <C> (t);
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, ClassInfo <T>::getClassKey ());
|
||||
// If this goes off it means the class T is unregistered!
|
||||
assert (lua_istable (L, -1));
|
||||
lua_setmetatable (L, -2);
|
||||
}
|
||||
else
|
||||
{
|
||||
lua_pushnil (L);
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
// const objects
|
||||
template <class C>
|
||||
struct UserdataSharedHelper <C, true>
|
||||
{
|
||||
typedef typename TypeTraits::removeConst <
|
||||
typename ContainerTraits <C>::Type>::Type T;
|
||||
|
||||
static void push (lua_State* L, C const& c)
|
||||
{
|
||||
if (ContainerTraits <C>::get (c) != 0)
|
||||
{
|
||||
new (lua_newuserdata (L, sizeof (UserdataShared <C>))) UserdataShared <C> (c);
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, ClassInfo <T>::getConstKey ());
|
||||
// If this goes off it means the class T is unregistered!
|
||||
assert (lua_istable (L, -1));
|
||||
lua_setmetatable (L, -2);
|
||||
}
|
||||
else
|
||||
{
|
||||
lua_pushnil (L);
|
||||
}
|
||||
}
|
||||
|
||||
static void push (lua_State* L, T* const t)
|
||||
{
|
||||
if (t)
|
||||
{
|
||||
new (lua_newuserdata (L, sizeof (UserdataShared <C>))) UserdataShared <C> (t);
|
||||
lua_rawgetp (L, LUA_REGISTRYINDEX, ClassInfo <T>::getConstKey ());
|
||||
// If this goes off it means the class T is unregistered!
|
||||
assert (lua_istable (L, -1));
|
||||
lua_setmetatable (L, -2);
|
||||
}
|
||||
else
|
||||
{
|
||||
lua_pushnil (L);
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
/**
|
||||
Pass by container.
|
||||
|
||||
The container controls the object lifetime. Typically this will be a
|
||||
lifetime shared by C++ and Lua using a reference count. Because of type
|
||||
erasure, containers like std::shared_ptr will not work. Containers must
|
||||
either be of the intrusive variety, or in the style of the RefCountedPtr
|
||||
type provided by LuaBridge (that uses a global hash table).
|
||||
*/
|
||||
template <class C, bool byContainer>
|
||||
struct StackHelper
|
||||
{
|
||||
static void push (lua_State* L, C const& c)
|
||||
{
|
||||
UserdataSharedHelper <C,
|
||||
TypeTraits::isConst <typename ContainerTraits <C>::Type>::value>::push (L, c);
|
||||
}
|
||||
|
||||
typedef typename TypeTraits::removeConst <
|
||||
typename ContainerTraits <C>::Type>::Type T;
|
||||
|
||||
static C get (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::get <T> (L, index, true);
|
||||
}
|
||||
};
|
||||
|
||||
/**
|
||||
Pass by value.
|
||||
|
||||
Lifetime is managed by Lua. A C++ function which accesses a pointer or
|
||||
reference to an object outside the activation record in which it was
|
||||
retrieved may result in undefined behavior if Lua garbage collected it.
|
||||
*/
|
||||
template <class T>
|
||||
struct StackHelper <T, false>
|
||||
{
|
||||
static inline void push (lua_State* L, T const& t)
|
||||
{
|
||||
UserdataValue <T>::push (L, t);
|
||||
}
|
||||
|
||||
static inline T const& get (lua_State* L, int index)
|
||||
{
|
||||
return *Userdata::get <T> (L, index, true);
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
/**
|
||||
Lua stack conversions for pointers and references to class objects.
|
||||
|
||||
Lifetime is managed by C++. Lua code which remembers a reference to the
|
||||
value may result in undefined behavior if C++ destroys the object. The
|
||||
handling of the const and volatile qualifiers happens in UserdataPtr.
|
||||
*/
|
||||
|
||||
template <class C, bool byContainer>
|
||||
struct RefStackHelper
|
||||
{
|
||||
typedef C return_type;
|
||||
|
||||
static inline void push (lua_State* L, C const& t)
|
||||
{
|
||||
UserdataSharedHelper <C,
|
||||
TypeTraits::isConst <typename ContainerTraits <C>::Type>::value>::push (L, t);
|
||||
}
|
||||
|
||||
typedef typename TypeTraits::removeConst <
|
||||
typename ContainerTraits <C>::Type>::Type T;
|
||||
|
||||
static return_type get (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::get <T> (L, index, true);
|
||||
}
|
||||
};
|
||||
|
||||
template <class T>
|
||||
struct RefStackHelper <T, false>
|
||||
{
|
||||
typedef T& return_type;
|
||||
|
||||
static void push (lua_State* L, T const& t)
|
||||
{
|
||||
UserdataPtr::push (L, &t);
|
||||
}
|
||||
|
||||
static return_type get (lua_State* L, int index)
|
||||
{
|
||||
T* t = Userdata::get <T> (L, index, true);
|
||||
|
||||
if (!t)
|
||||
luaL_error (L, "nil passed to reference");
|
||||
return *t;
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* Voider class template. Used to force a comiler to instantiate
|
||||
* an otherwise probably unused template parameter type T.
|
||||
* See the C++20 std::void_t <> for details.
|
||||
*/
|
||||
template <class T>
|
||||
struct Void
|
||||
{
|
||||
typedef void Type;
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* Trait class that selects whether to return a user registered
|
||||
* class object by value or by reference.
|
||||
*/
|
||||
|
||||
template <class T, class Enabler = void>
|
||||
struct UserdataGetter
|
||||
{
|
||||
typedef T* ReturnType;
|
||||
|
||||
static ReturnType get (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::get <T> (L, index, false);
|
||||
}
|
||||
};
|
||||
|
||||
template <class T>
|
||||
struct UserdataGetter <T, typename Void <T (*) ()>::Type>
|
||||
{
|
||||
typedef T ReturnType;
|
||||
|
||||
static ReturnType get (lua_State* L, int index)
|
||||
{
|
||||
return StackHelper <T, TypeTraits::isContainer <T>::value>::get (L, index);
|
||||
}
|
||||
};
|
||||
|
||||
//==============================================================================
|
||||
|
||||
/**
|
||||
Lua stack conversions for class objects passed by value.
|
||||
*/
|
||||
template <class T>
|
||||
struct Stack
|
||||
{
|
||||
typedef void IsUserdata;
|
||||
|
||||
typedef UserdataGetter <T> Getter;
|
||||
typedef typename Getter::ReturnType ReturnType;
|
||||
|
||||
static void push (lua_State* L, T const& value)
|
||||
{
|
||||
StackHelper <T, TypeTraits::isContainer <T>::value>::push (L, value);
|
||||
}
|
||||
|
||||
static ReturnType get (lua_State* L, int index)
|
||||
{
|
||||
return Getter::get (L, index);
|
||||
}
|
||||
|
||||
static bool isInstance (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::isInstance <T> (L, index);
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* Trait class indicating whether the parameter type must be
|
||||
* a user registered class. The trait checks the existence of
|
||||
* member type Stack <T>::IsUserdata specialization for detection.
|
||||
*/
|
||||
template <class T, class Enable = void>
|
||||
struct IsUserdata
|
||||
{
|
||||
static const bool value = false;
|
||||
};
|
||||
|
||||
template <class T>
|
||||
struct IsUserdata <T, typename Void <typename Stack <T>::IsUserdata>::Type>
|
||||
{
|
||||
static const bool value = true;
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* Trait class that selects a specific push/get implemenation.
|
||||
*/
|
||||
template <class T, bool isUserdata>
|
||||
struct StackOpSelector;
|
||||
|
||||
// pointer
|
||||
template <class T>
|
||||
struct StackOpSelector <T*, true>
|
||||
{
|
||||
typedef T* ReturnType;
|
||||
|
||||
static void push (lua_State* L, T* value)
|
||||
{
|
||||
UserdataPtr::push (L, value);
|
||||
}
|
||||
|
||||
static T* get (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::get <T> (L, index, false);
|
||||
}
|
||||
|
||||
static bool isInstance (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::isInstance <T> (L, index);
|
||||
}
|
||||
};
|
||||
|
||||
// pointer to const
|
||||
template <class T>
|
||||
struct StackOpSelector <const T*, true>
|
||||
{
|
||||
typedef const T* ReturnType;
|
||||
|
||||
static void push (lua_State* L, const T* value)
|
||||
{
|
||||
UserdataPtr::push (L, value);
|
||||
}
|
||||
|
||||
static const T* get (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::get <T> (L, index, true);
|
||||
}
|
||||
|
||||
static bool isInstance (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::isInstance <T> (L, index);
|
||||
}
|
||||
};
|
||||
|
||||
// reference
|
||||
template <class T>
|
||||
struct StackOpSelector <T&, true>
|
||||
{
|
||||
typedef RefStackHelper <T, TypeTraits::isContainer <T>::value> Helper;
|
||||
typedef typename Helper::return_type ReturnType;
|
||||
|
||||
static void push (lua_State* L, T& value)
|
||||
{
|
||||
UserdataPtr::push (L, &value);
|
||||
}
|
||||
|
||||
static ReturnType get (lua_State* L, int index)
|
||||
{
|
||||
return Helper::get (L, index);
|
||||
}
|
||||
|
||||
static bool isInstance (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::isInstance <T> (L, index);
|
||||
}
|
||||
};
|
||||
|
||||
// reference to const
|
||||
template <class T>
|
||||
struct StackOpSelector <const T&, true>
|
||||
{
|
||||
typedef RefStackHelper <T, TypeTraits::isContainer <T>::value> Helper;
|
||||
typedef typename Helper::return_type ReturnType;
|
||||
|
||||
static void push (lua_State* L, const T& value)
|
||||
{
|
||||
Helper::push (L, value);
|
||||
}
|
||||
|
||||
static ReturnType get (lua_State* L, int index)
|
||||
{
|
||||
return Helper::get (L, index);
|
||||
}
|
||||
|
||||
static bool isInstance (lua_State* L, int index)
|
||||
{
|
||||
return Userdata::isInstance <T> (L, index);
|
||||
}
|
||||
};
|
||||
|
||||
} // namespace luabridge
|
||||
Reference in New Issue
Block a user