summaryrefslogtreecommitdiff
path: root/lua/lmem.c
diff options
context:
space:
mode:
Diffstat (limited to 'lua/lmem.c')
-rw-r--r--lua/lmem.c91
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;
+}
+