* ext/openssl/ossl_config.c: refine all with backward compatibility.
* ext/openssl/ossl_config.h: export GetConfigPtr() and DupConfigPtr().
* ext/openssl/ossl_x509.c: added new constants under X509 module.
DEFAULT_CERT_AREA, DEFAULT_CERT_DIR, DEFAULT_CERT_FILE,
DEFAULT_CERT_DIR_ENV, DEFAULT_CERT_FILE_ENV and DEFAULT_PRIVATE_DIR.
* ext/openssl/ossl_x509ext.c (ossl_x509extfactory_free): don't free
the members of the struct. it's left to GC.
* ext/openssl/ossl_x509ext.c (ossl_x509_set_config): add for config=.
* ext/openssl/ossl_x509ext.c (Xossl_x509extfactory_initialize):
add attr readers: issuer_certificate, subject_certificate,
subject_request, crl and config.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@4531 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
