Warn on access/modify of $SAFE, and remove effects of modifying $SAFE

This removes the security features added by $SAFE = 1, and warns for access
or modification of $SAFE from Ruby-level, as well as warning when calling
all public C functions related to $SAFE.

This modifies some internal functions that took a safe level argument
to no longer take the argument.

rb_require_safe now warns, rb_require_string has been added as a
version that takes a VALUE and does not warn.

One public C function that still takes a safe level argument and that
this doesn't warn for is rb_eval_cmd.  We may want to consider
adding an alternative method that does not take a safe level argument,
and warn for rb_eval_cmd.

1 files changed, 0 insertions, 3 deletions

diff --git a/io.c b/io.c
index f4dc499633..47d37d121a 100644
--- a/io.c
+++ b/io.c
@@ -12839,9 +12839,6 @@ opt_i_get(ID id, VALUE *var)
 static VALUE
 argf_inplace_mode_set(VALUE argf, VALUE val)
 {
-    if (rb_safe_level() >= 1 && OBJ_TAINTED(val))
-	rb_insecure_operation();
-
     if (!RTEST(val)) {
 	ARGF.inplace = Qfalse;
     }