- boost_zip = env.URLDownload(boost_arch_name, boost_url)
- boost_dir = env.UnpackAll(boost_bootstrap, boost_zip)
- boost_b2 = env.BoostBootstrap(boost_b2_name, boost_dir)
+ if not os.path.exists(boost_arch_name) and not os.path.exists(boost_base_name):
+ boost_arch_name = env.URLDownload(boost_arch_name, boost_url)
+
+ if not os.path.exists(boost_base_name):
+ boost_arch_name = env.UnpackAll(boost_bootstrap, boost_arch_name)
+
+ boost_b2 = env.BoostBootstrap(boost_b2_name, boost_arch_name)