1 /* $NetBSD: lmem.h,v 1.3 2015/02/02 14:03:05 lneto Exp $ */ 2 3 /* 4 ** Id: lmem.h,v 1.43 2014/12/19 17:26:14 roberto Exp 5 ** Interface to Memory Manager 6 ** See Copyright Notice in lua.h 7 */ 8 9 #ifndef lmem_h 10 #define lmem_h 11 12 13 #ifndef _KERNEL 14 #include <stddef.h> 15 #endif 16 17 #include "llimits.h" 18 #include "lua.h" 19 20 21 /* 22 ** This macro reallocs a vector 'b' from 'on' to 'n' elements, where 23 ** each element has size 'e'. In case of arithmetic overflow of the 24 ** product 'n'*'e', it raises an error (calling 'luaM_toobig'). Because 25 ** 'e' is always constant, it avoids the runtime division MAX_SIZET/(e). 26 ** 27 ** (The macro is somewhat complex to avoid warnings: The 'sizeof' 28 ** comparison avoids a runtime comparison when overflow cannot occur. 29 ** The compiler should be able to optimize the real test by itself, but 30 ** when it does it, it may give a warning about "comparison is always 31 ** false due to limited range of data type"; the +1 tricks the compiler, 32 ** avoiding this warning but also this optimization.) 33 */ 34 #define luaM_reallocv(L,b,on,n,e) \ 35 (((sizeof(n) >= sizeof(size_t) && cast(size_t, (n)) + 1 > MAX_SIZET/(e)) \ 36 ? luaM_toobig(L) : cast_void(0)) , \ 37 luaM_realloc_(L, (b), (on)*(e), (n)*(e))) 38 39 /* 40 ** Arrays of chars do not need any test 41 */ 42 #define luaM_reallocvchar(L,b,on,n) \ 43 cast(char *, luaM_realloc_(L, (b), (on)*sizeof(char), (n)*sizeof(char))) 44 45 #define luaM_freemem(L, b, s) luaM_realloc_(L, (b), (s), 0) 46 #define luaM_free(L, b) luaM_realloc_(L, (b), sizeof(*(b)), 0) 47 #define luaM_freearray(L, b, n) luaM_realloc_(L, (b), (n)*sizeof(*(b)), 0) 48 49 #define luaM_malloc(L,s) luaM_realloc_(L, NULL, 0, (s)) 50 #define luaM_new(L,t) cast(t *, luaM_malloc(L, sizeof(t))) 51 #define luaM_newvector(L,n,t) \ 52 cast(t *, luaM_reallocv(L, NULL, 0, n, sizeof(t))) 53 54 #define luaM_newobject(L,tag,s) luaM_realloc_(L, NULL, tag, (s)) 55 56 #define luaM_growvector(L,v,nelems,size,t,limit,e) \ 57 if ((nelems)+1 > (size)) \ 58 ((v)=cast(t *, luaM_growaux_(L,v,&(size),sizeof(t),limit,e))) 59 60 #define luaM_reallocvector(L, v,oldn,n,t) \ 61 ((v)=cast(t *, luaM_reallocv(L, v, oldn, n, sizeof(t)))) 62 63 LUAI_FUNC l_noret luaM_toobig (lua_State *L); 64 65 /* not to be called directly */ 66 LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize, 67 size_t size); 68 LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int *size, 69 size_t size_elem, int limit, 70 const char *what); 71 72 #endif 73 74