Fixed 4984: (Lua math.randomseed() gets stuck with large numbers)

Signed-off-by: ccw808 <ccw808@googlemail.com>

Author: ccw808

src/lapi.c

@@ -334,6 +334,21 @@ LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) {
 }
 
 
+LUA_API lua_Integer lua_tointegerW (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  if (tonumber(o, &n)) {
+    lua_Integer res;
+    lua_Number num = nvalue(o);
+    num = fmod( num, 0x7fffffff );   // Wrap the number between -2,147,483,647 and 2,147,483,647
+    lua_number2integer(res, num);
+    return res;
+  }
+  else
+    return 0;
+}
+
+
 LUA_API int lua_toboolean (lua_State *L, int idx) {
   const TValue *o = index2adr(L, idx);
   return !l_isfalse(o);

src/lmathlib.c

@@ -206,8 +206,12 @@ static int math_random (lua_State *L) {
 
 
 static int math_randomseed (lua_State *L) {
-  srand(luaL_checkint(L, 1));
-  return 0;
+    // lua_tointegerW wraps out of range numbers (luaL_checkint clips values below -1^32 and above 1^32)
+    srand(lua_tointegerW(L, 1));
+    // Do some rands here, as the first few results bear a close relationship to the seed number
+    rand();
+    rand();
+    return 0;
 }
 
 

src/lua.h

@@ -153,6 +153,7 @@ LUA_API int            (lua_lessthan) (lua_State *L, int idx1, int idx2);
 
 LUA_API lua_Number      (lua_tonumber) (lua_State *L, int idx);
 LUA_API lua_Integer     (lua_tointeger) (lua_State *L, int idx);
+LUA_API lua_Integer     (lua_tointegerW) (lua_State *L, int idx);
 LUA_API int             (lua_toboolean) (lua_State *L, int idx);
 LUA_API const char     *(lua_tolstring) (lua_State *L, int idx, size_t *len);
 LUA_API size_t          (lua_objlen) (lua_State *L, int idx);