toolbox: Make have(), _try_include(), include() read-only

Functions from toolbox.sh may be redeclared, causing all sorts of
problems from simple bugs to security issues.
This commit makes sure the functions are declared read-only when
toolbox is loaded so the user can't shoot themself in the foot.

diff --git a/toolbox.sh b/toolbox.sh
index 6261219c688638a03b197eb398a427ae10351dca..f690b01d09c18e410922540ef96ab078cbf1d296 100644 (file)
--- a/toolbox.sh
+++ b/toolbox.sh
@@ -33,6 +33,10 @@ __toolbox_init() {
 
        declare -Axg __TOOLBOX_INCLUDED
 
+       readonly -f have
+       readonly -f _try_include
+       readonly -f include
+
        return 0
 }