Chris Green <[EMAIL PROTECTED]> writes:
> I'm just now learning NASL to do things more complicated than an
> automated wget. Is there a special ordering that the display()
> requires?
No. But you found a bug, congratulations! The bug is in the loop, not
in display(). It comes from an old behaviour that was disabled by
default with #ifdef STOP_AT_FIRST_ERROR
It is still here because it might be an interesting behaviour after
all...
By the way, inspecting the rest of the code, I found a couple of other
similar errors, e.g. with if / else
if (test) expr1; else expr2;
will execute neither expr1 or expr2 if the test returns an error
Note that this case does not happen often, that's why it was
undetected until now.
Here is a patch...
I let Renaud decide if we commit it now (we probably need some testing
to check that it did not break some test that would rely on the bug)
--- nasl/exec.c 1 Mar 2003 12:16:53 -0000 1.42
+++ nasl/exec.c 31 Mar 2003 22:07:07 -0000
@@ -793,8 +793,11 @@
switch(st->type)
{
case NODE_IF_ELSE:
- if ((ret = nasl_exec(lexic, st->link[0])) == NULL)
+ ret = nasl_exec(lexic, st->link[0]);
+#ifdef STOP_AT_FIRST_ERROR
+ if (ret == NULL)
return NULL;
+#endif
if (cvt_bool(lexic, ret))
ret2 = nasl_exec(lexic, st->link[1]);
else
@@ -819,8 +822,11 @@
case NODE_FOR:
/* [0] = start expr, [1] = cond, [2] = end_expr, [3] = block */
- if ((ret2 = nasl_exec(lexic, st->link[0])) == NULL)
+ ret2 = nasl_exec(lexic, st->link[0]);
+#ifdef STOP_AT_FIRST_ERROR
+ if (ret2 == NULL)
return NULL;
+#endif
deref_cell(ret2);
for (;;)
{
@@ -833,14 +839,17 @@
/* condition */
if ((ret = nasl_exec(lexic, st->link[1])) == NULL)
- return NULL;
+ return NULL; /* We can return here, as NULL is false */
flag = cvt_bool(lexic, ret);
deref_cell(ret);
if (! flag)
break;
/* block */
- if ((ret = nasl_exec(lexic, st->link[3])) == NULL)
+ ret = nasl_exec(lexic, st->link[3]);
+#ifdef STOP_AT_FIRST_ERROR
+ if (ret == NULL)
return NULL;
+#endif
deref_cell(ret);
/* break */
@@ -851,8 +860,11 @@
}
/* end expression */
- if ((ret = nasl_exec(lexic, st->link[2])) == NULL)
+ ret = nasl_exec(lexic, st->link[2]);
+#ifdef STOP_AT_FIRST_ERROR
+ if (ret == NULL)
return NULL;
+#endif
deref_cell(ret);
}
return FAKE_CELL;
@@ -869,7 +881,7 @@
}
/* Condition */
if ((ret = nasl_exec(lexic, st->link[0])) == NULL)
- return NULL;
+ return NULL; /* NULL is false */
flag = cvt_bool(lexic, ret);
deref_cell(ret);
if (! flag)
@@ -937,7 +949,7 @@
v = get_variable_by_name(lexic, st->x.str_val);
if (v == NULL)
- return NULL;
+ return NULL; /* We cannot go on if we have no variable to iterate */
a = nasl_exec(lexic, st->link[0]);
ai = nasl_array_iterator(a);
while ((val = nasl_iterate_array(&ai)) != NULL)
