1 files changed, 29 insertions, 16 deletions

diff --git a/apps/plugins/lua/lmem.c b/apps/plugins/lua/lmem.c
index ae7d8c965f..ee343e3e03 100644
--- a/apps/plugins/lua/lmem.c
+++ b/apps/plugins/lua/lmem.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lmem.c,v 1.70.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lmem.c,v 1.84.1.1 2013/04/12 18:48:47 roberto Exp $
 ** Interface to Memory Manager
 ** See Copyright Notice in lua.h
 */
@@ -14,6 +14,7 @@
 
 #include "ldebug.h"
 #include "ldo.h"
+#include "lgc.h"
 #include "lmem.h"
 #include "lobject.h"
 #include "lstate.h"
@@ -25,12 +26,11 @@
 ** void * frealloc (void *ud, void *ptr, size_t osize, size_t nsize);
 ** (`osize' is the old size, `nsize' is the new size)
 **
-** Lua ensures that (ptr == NULL) iff (osize == 0).
-**
-** * frealloc(ud, NULL, 0, x) creates a new block of size `x'
+** * 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).
+** (in this specific case, frealloc must return NULL);
 ** particularly, frealloc(ud, NULL, 0, 0) does nothing
 ** (which is equivalent to free(NULL) in ANSI C)
 **
@@ -44,12 +44,12 @@
 
 
 void *luaM_growaux_ (lua_State *L, void *block, int *size, size_t size_elems,
-                     int limit, const char *errormsg) {
+                     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, errormsg);
+      luaG_runerror(L, "too many %s (limit is %d)", what, limit);
     newsize = limit;  /* still have at least one free place */
   }
   else {
@@ -63,9 +63,8 @@ void *luaM_growaux_ (lua_State *L, void *block, int *size, size_t size_elems,
 }
 
 
-void *luaM_toobig (lua_State *L) {
+l_noret luaM_toobig (lua_State *L) {
   luaG_runerror(L, "memory allocation error: block too big");
-  return NULL;  /* to avoid warnings */
 }
 
 
@@ -74,13 +73,27 @@ void *luaM_toobig (lua_State *L) {
 ** generic allocation routine.
 */
 void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
+  void *newblock;
   global_State *g = G(L);
-  lua_assert((osize == 0) == (block == NULL));
-  block = (*g->frealloc)(g->ud, block, osize, nsize);
-  if (block == NULL && nsize > 0)
-    luaD_throw(L, LUA_ERRMEM);
-  lua_assert((nsize == 0) == (block == NULL));
-  g->totalbytes = (g->totalbytes - osize) + nsize;
-  return block;
+  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) {
+    api_check(L, nsize > realosize,
+                 "realloc cannot fail when shrinking a block");
+    if (g->gcrunning) {
+      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;
 }