| /* |
| ** $Id: lmem.h $ |
| ** 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" |
| |
| |
| #define luaM_error(L) luaD_throw(L, LUA_ERRMEM) |
| |
| |
| /* |
| ** This macro tests whether it is safe to multiply 'n' by the size of |
| ** type 't' without overflows. 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_testsize(n,e) \ |
| (sizeof(n) >= sizeof(size_t) && cast_sizet((n)) + 1 > MAX_SIZET/(e)) |
| |
| #define luaM_checksize(L,n,e) \ |
| (luaM_testsize(n,e) ? luaM_toobig(L) : cast_void(0)) |
| |
| |
| /* |
| ** Computes the minimum between 'n' and 'MAX_SIZET/sizeof(t)', so that |
| ** the result is not larger than 'n' and cannot overflow a 'size_t' |
| ** when multiplied by the size of type 't'. (Assumes that 'n' is an |
| ** 'int' or 'unsigned int' and that 'int' is not larger than 'size_t'.) |
| */ |
| #define luaM_limitN(n,t) \ |
| ((cast_sizet(n) <= MAX_SIZET/sizeof(t)) ? (n) : \ |
| cast_uint((MAX_SIZET/sizeof(t)))) |
| |
| |
| /* |
| ** Arrays of chars do not need any test |
| */ |
| #define luaM_reallocvchar(L,b,on,n) \ |
| cast_charp(luaM_saferealloc_(L, (b), (on)*sizeof(char), (n)*sizeof(char))) |
| |
| #define luaM_freemem(L, b, s) luaM_free_(L, (b), (s)) |
| #define luaM_free(L, b) luaM_free_(L, (b), sizeof(*(b))) |
| #define luaM_freearray(L, b, n) luaM_free_(L, (b), (n)*sizeof(*(b))) |
| |
| #define luaM_new(L,t) cast(t*, luaM_malloc_(L, sizeof(t), 0)) |
| #define luaM_newvector(L,n,t) cast(t*, luaM_malloc_(L, (n)*sizeof(t), 0)) |
| #define luaM_newvectorchecked(L,n,t) \ |
| (luaM_checksize(L,n,sizeof(t)), luaM_newvector(L,n,t)) |
| |
| #define luaM_newobject(L,tag,s) luaM_malloc_(L, (s), tag) |
| |
| #define luaM_newblock(L, size) luaM_newvector(L, size, char) |
| |
| #define luaM_growvector(L,v,nelems,size,t,limit,e) \ |
| ((v)=cast(t *, luaM_growaux_(L,v,nelems,&(size),sizeof(t), \ |
| luaM_limitN(limit,t),e))) |
| |
| #define luaM_reallocvector(L, v,oldn,n,t) \ |
| (cast(t *, luaM_realloc_(L, v, cast_sizet(oldn) * sizeof(t), \ |
| cast_sizet(n) * sizeof(t)))) |
| |
| #define luaM_shrinkvector(L,v,size,fs,t) \ |
| ((v)=cast(t *, luaM_shrinkvector_(L, v, &(size), fs, 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_saferealloc_ (lua_State *L, void *block, size_t oldsize, |
| size_t size); |
| LUAI_FUNC void luaM_free_ (lua_State *L, void *block, size_t osize); |
| LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int nelems, |
| int *size, unsigned size_elem, int limit, |
| const char *what); |
| LUAI_FUNC void *luaM_shrinkvector_ (lua_State *L, void *block, int *nelem, |
| int final_n, unsigned size_elem); |
| LUAI_FUNC void *luaM_malloc_ (lua_State *L, size_t size, int tag); |
| |
| #endif |
| |