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- /*
- ** $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
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