aboutsummaryrefslogtreecommitdiff
path: root/src/lib/lua/lmem.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/lib/lua/lmem.c')
-rw-r--r--src/lib/lua/lmem.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/src/lib/lua/lmem.c b/src/lib/lua/lmem.c
new file mode 100644
index 0000000..0a0476c
--- /dev/null
+++ b/src/lib/lua/lmem.c
@@ -0,0 +1,100 @@
+/*
+** $Id: lmem.c,v 1.91 2015/03/06 19:45:54 roberto Exp $
+** Interface to Memory Manager
+** See Copyright Notice in lua.h
+*/
+
+#define lmem_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+
+/*
+** About the realloc function:
+** void * frealloc (void *ud, void *ptr, size_t osize, size_t nsize);
+** ('osize' is the old size, 'nsize' is the new size)
+**
+** * frealloc(ud, NULL, x, s) creates a new block of size 's' (no
+** matter 'x').
+**
+** * frealloc(ud, p, x, 0) frees the block 'p'
+** (in this specific case, frealloc must return NULL);
+** particularly, frealloc(ud, NULL, 0, 0) does nothing
+** (which is equivalent to free(NULL) in ISO C)
+**
+** frealloc returns NULL if it cannot create or reallocate the area
+** (any reallocation to an equal or smaller size cannot fail!)
+*/
+
+
+
+#define MINSIZEARRAY 4
+
+
+void *luaM_growaux_ (lua_State *L, void *block, int *size, size_t size_elems,
+ int limit, const char *what) {
+ void *newblock;
+ int newsize;
+ if (*size >= limit/2) { /* cannot double it? */
+ if (*size >= limit) /* cannot grow even a little? */
+ luaG_runerror(L, "too many %s (limit is %d)", what, limit);
+ newsize = limit; /* still have at least one free place */
+ }
+ else {
+ newsize = (*size)*2;
+ if (newsize < MINSIZEARRAY)
+ newsize = MINSIZEARRAY; /* minimum size */
+ }
+ newblock = luaM_reallocv(L, block, *size, newsize, size_elems);
+ *size = newsize; /* update only when everything else is OK */
+ return newblock;
+}
+
+
+l_noret luaM_toobig (lua_State *L) {
+ luaG_runerror(L, "memory allocation error: block too big");
+}
+
+
+
+/*
+** generic allocation routine.
+*/
+void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
+ void *newblock;
+ global_State *g = G(L);
+ size_t realosize = (block) ? osize : 0;
+ lua_assert((realosize == 0) == (block == NULL));
+#if defined(HARDMEMTESTS)
+ if (nsize > realosize && g->gcrunning)
+ luaC_fullgc(L, 1); /* force a GC whenever possible */
+#endif
+ newblock = (*g->frealloc)(g->ud, block, osize, nsize);
+ if (newblock == NULL && nsize > 0) {
+ lua_assert(nsize > realosize); /* cannot fail when shrinking a block */
+ if (g->version) { /* is state fully built? */
+ luaC_fullgc(L, 1); /* try to free some memory... */
+ newblock = (*g->frealloc)(g->ud, block, osize, nsize); /* try again */
+ }
+ if (newblock == NULL)
+ luaD_throw(L, LUA_ERRMEM);
+ }
+ lua_assert((nsize == 0) == (newblock == NULL));
+ g->GCdebt = (g->GCdebt + nsize) - realosize;
+ return newblock;
+}
+