diff options
Diffstat (limited to 'lua/lmem.c')
-rw-r--r-- | lua/lmem.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/lua/lmem.c b/lua/lmem.c new file mode 100644 index 000000000..84b9a9208 --- /dev/null +++ b/lua/lmem.c @@ -0,0 +1,91 @@ +/* +** $Id: lmem.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $ +** Interface to Memory Manager +** See Copyright Notice in lua.h +*/ + + +#include <stdlib.h> + +#define lmem_c + +#include "lua.h" + +#include "ldebug.h" +#include "ldo.h" +#include "lmem.h" +#include "lobject.h" +#include "lstate.h" + + + +/* +** definition for realloc function. It must assure that l_realloc(NULL, +** 0, x) allocates a new block (ANSI C assures that). (`os' is the old +** block size; some allocators may use that.) +*/ +#ifndef l_realloc +#define l_realloc(b,os,s) realloc(b,s) +#endif + +/* +** definition for free function. (`os' is the old block size; some +** allocators may use that.) +*/ +#ifndef l_free +#define l_free(b,os) free(b) +#endif + + +#define MINSIZEARRAY 4 + + +void *luaM_growaux (lua_State *L, void *block, int *size, int size_elems, + int limit, const char *errormsg) { + void *newblock; + int newsize = (*size)*2; + if (newsize < MINSIZEARRAY) + newsize = MINSIZEARRAY; /* minimum size */ + else if (*size >= limit/2) { /* cannot double it? */ + if (*size < limit - MINSIZEARRAY) /* try something smaller... */ + newsize = limit; /* still have at least MINSIZEARRAY free places */ + else luaG_runerror(L, errormsg); + } + newblock = luaM_realloc(L, block, + cast(lu_mem, *size)*cast(lu_mem, size_elems), + cast(lu_mem, newsize)*cast(lu_mem, size_elems)); + *size = newsize; /* update only when everything else is OK */ + return newblock; +} + + +/* +** generic allocation routine. +*/ +void *luaM_realloc (lua_State *L, void *block, lu_mem oldsize, lu_mem size) { + lua_assert((oldsize == 0) == (block == NULL)); + if (size == 0) { + if (block != NULL) { + l_free(block, oldsize); + block = NULL; + } + else return NULL; /* avoid `nblocks' computations when oldsize==size==0 */ + } + else if (size >= MAX_SIZET) + luaG_runerror(L, "memory allocation error: block too big"); + else { + block = l_realloc(block, oldsize, size); + if (block == NULL) { + if (L) + luaD_throw(L, LUA_ERRMEM); + else return NULL; /* error before creating state! */ + } + } + if (L) { + lua_assert(G(L) != NULL && G(L)->nblocks > 0); + G(L)->nblocks -= oldsize; + G(L)->nblocks += size; + } + return block; +} + |