use of int and overflow review

[chiark-tcl.git] / hbytes / chop.c

diff --git a/hbytes/chop.c b/hbytes/chop.c
index 3e48569ff63bfa343b8984d09a385ba6c7a91338..e649b5aa12a4dce45eb4ade79de62d2347d21c06 100644 (file)
--- a/hbytes/chop.c
+++ b/hbytes/chop.c
@@ -22,13 +22,15 @@
 #include "chiark_tcl_hbytes.h"
 
 static int strs1(Tcl_Interp *ip, int strc, Tcl_Obj *const *strv, int *l_r) {
 #include "chiark_tcl_hbytes.h"
 
 static int strs1(Tcl_Interp *ip, int strc, Tcl_Obj *const *strv, int *l_r) {

-  int rc, l, i;
+  int rc, l, i, pl;

 
   l= 0;
   for (i=1; i<strc; i++) {
     rc= Tcl_ConvertToType(ip,strv[i],&cht_hbytes_type);
     if (rc) return rc;
 
   l= 0;
   for (i=1; i<strc; i++) {
     rc= Tcl_ConvertToType(ip,strv[i],&cht_hbytes_type);
     if (rc) return rc;

-    l += cht_hb_len(OBJ_HBYTES(strv[i]));
+    pl= cht_hb_len(OBJ_HBYTES(strv[i]));
+    assert(l < INT_MAX/2 && pl < INT_MAX/2);
+    l += pl;

   }
   *l_r= l;
   return TCL_OK;
   }
   *l_r= l;
   return TCL_OK;