/*
** $Id: lmem.h,v 1.43 2014/12/19 17:26:14 roberto Exp $
** Interface to Memory Manager
** See Copyright Notice in lua.h
*/

#ifndef lmem_h
#define lmem_h

#include <stddef.h>

#include "llimits.h"
#include "lua.h"

/*
** This macro reallocs a vector 'b' from 'on' to 'n' elements, where
** each element has size 'e'. In case of arithmetic overflow of the
** product 'n'*'e', it raises an error (calling 'luaM_toobig'). Because
** 'e' is always constant, it avoids the runtime division MAX_SIZET/(e).
**
** (The macro is somewhat complex to avoid warnings:  The 'sizeof'
** comparison avoids a runtime comparison when overflow cannot occur.
** The compiler should be able to optimize the real test by itself, but
** when it does it, it may give a warning about "comparison is always
** false due to limited range of data type"; the +1 tricks the compiler,
** avoiding this warning but also this optimization.)
*/
#define luaM_reallocv(L, b, on, n, e)                                                              \
	(((sizeof(n) >= sizeof(size_t) && cast(size_t, (n)) + 1 > MAX_SIZET / (e)) ? luaM_toobig(L) :   \
	                                                                             cast_void(0)),     \
	 luaM_realloc_(L, (b), (on) * (e), (n) * (e)))

/*
** Arrays of chars do not need any test
*/
#define luaM_reallocvchar(L, b, on, n)                                                             \
	cast(char*, luaM_realloc_(L, (b), (on) * sizeof(char), (n) * sizeof(char)))

#define luaM_freemem(L, b, s) luaM_realloc_(L, (b), (s), 0)
#define luaM_free(L, b) luaM_realloc_(L, (b), sizeof(*(b)), 0)
#define luaM_freearray(L, b, n) luaM_realloc_(L, (b), (n) * sizeof(*(b)), 0)

#define luaM_malloc(L, s) luaM_realloc_(L, NULL, 0, (s))
#define luaM_new(L, t) cast(t*, luaM_malloc(L, sizeof(t)))
#define luaM_newvector(L, n, t) cast(t*, luaM_reallocv(L, NULL, 0, n, sizeof(t)))

#define luaM_newobject(L, tag, s) luaM_realloc_(L, NULL, tag, (s))

#define luaM_growvector(L, v, nelems, size, t, limit, e)                                           \
	if ((nelems) + 1 > (size))                                                                      \
	((v) = cast(t*, luaM_growaux_(L, v, &(size), sizeof(t), limit, e)))

#define luaM_reallocvector(L, v, oldn, n, t)                                                       \
	((v) = cast(t*, luaM_reallocv(L, v, oldn, n, sizeof(t))))

LUAI_FUNC l_noret luaM_toobig(lua_State* L);

/* not to be called directly */
LUAI_FUNC void* luaM_realloc_(lua_State* L, void* block, size_t oldsize, size_t size);
LUAI_FUNC void*
luaM_growaux_(lua_State* L, void* block, int* size, size_t size_elem, int limit, const char* what);

#endif
