rusefi
/
lua
mirror of https://github.com/rusefi/lua.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

bug: compiler could optimize away overflow check (+ changing indices 

from 'int' to 'lua_Integer')
This commit is contained in:
Roberto Ierusalimschy 2014-04-01 15:50:34 -03:00
parent 607be77ec8
commit 315c5bf7b7
1 changed files with 12 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
ltablib.c
View File

@ -1,10 +1,11 @@
/*
** $Id: ltablib.c,v 1.65 2013/03/07 18:17:24 roberto Exp roberto $
** $Id: ltablib.c,v 1.66 2014/03/21 13:52:33 roberto Exp roberto $
** Library for Table Manipulation
** See Copyright Notice in lua.h
*/
#include <limits.h>
#include <stddef.h>
#define ltablib_c
@ -134,17 +135,19 @@ static int pack (lua_State *L) {
static int unpack (lua_State *L) {
int i, e, n;
lua_Integer i, e;
lua_Unsigned n;
luaL_checktype(L, 1, LUA_TTABLE);
i = luaL_optint(L, 2, 1);
e = luaL_opt(L, luaL_checkint, 3, luaL_len(L, 1));
i = luaL_optinteger(L, 2, 1);
e = luaL_opt(L, luaL_checkinteger, 3, luaL_len(L, 1));
if (i > e) return 0; /* empty range */
n = e - i + 1; /* number of elements */
if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arithmetic overflow */
n = (lua_Unsigned)e - i; /* number of elements minus 1 (avoid overflows) */
if (n >= (lua_Unsigned)INT_MAX || !lua_checkstack(L, ++n))
return luaL_error(L, "too many results to unpack");
lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */
while (i++ < e) /* push arg[i + 1...e] */
lua_rawgeti(L, 1, i);
do { /* must have at least one element */
lua_rawgeti(L, 1, i); /* push arg[i..e] */
} while (i++ < e);
return n;
}