OpenSSL's SHA1 struct name is SHA_CTX (which is also used for SHA-0),
but function name is SHA1_Transform.
http://openssl.org/docs/man0.9.8/crypto/SHA1.html
also note that LibreSSL 2.3 remove the SHA-0 support but still support SHA-1.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52755 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* ext/digest/digest_conf.rb (digest_conf): check for CommonDigest.
* ext/digest/*/*cc.h: for Apple CommonCrypto/CommonDigest.h.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49565 b2dd03c8-39d4-4d8f-98ff-823fe69b080e