text: /* <!-- copyright */
  /*
   * aria2 - The high speed download utility
   *
   * Copyright (C) 2013 Nils Maier
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   *
   * In addition, as a special exception, the copyright holders give
   * permission to link the code of portions of this program with the
   * OpenSSL library under certain conditions as described in each
   * individual source file, and distribute linked combinations
   * including the two.
   * You must obey the GNU General Public License in all respects
   * for all of the code used other than OpenSSL.  If you modify
   * file(s) with this exception, you may extend this exception to your
   * version of the file(s), but you are not obligated to do so.  If you
   * do not wish to do so, delete this exception statement from your
   * version.  If you delete this exception statement from all source
   * files in the program, then also delete it here.
   */
  /* copyright --> */
  
  #include "MessageDigestImpl.h"
  
  #include <CommonCrypto/CommonDigest.h>
  
  #include "Adler32MessageDigestImpl.h"
  
  namespace aria2 {
  namespace {
  
  template <size_t dlen, typename ctx_t, int (*init_fn)(ctx_t*),
            int (*update_fn)(ctx_t*, const void*, CC_LONG),
            int (*final_fn)(unsigned char*, ctx_t*)>
  class MessageDigestBase : public MessageDigestImpl {
  public:
    MessageDigestBase() { reset(); }
    virtual ~MessageDigestBase() = default;
  
    static size_t length() { return dlen; }
    virtual size_t getDigestLength() const CXX11_OVERRIDE { return dlen; }
    virtual void reset() CXX11_OVERRIDE { init_fn(&ctx_); }
    virtual void update(const void* data, size_t length) CXX11_OVERRIDE
    {
      auto bytes = reinterpret_cast<const char*>(data);
      while (length) {
        CC_LONG l =
            std::min(length, (size_t)std::numeric_limits<uint32_t>::max());
        update_fn(&ctx_, bytes, l);
        length -= l;
        bytes += l;
      }
    }
    virtual void digest(unsigned char* md) CXX11_OVERRIDE { final_fn(md, &ctx_); }
  
  private:
    ctx_t ctx_;
  };
  
  typedef MessageDigestBase<CC_MD5_DIGEST_LENGTH, CC_MD5_CTX, CC_MD5_Init,
                            CC_MD5_Update, CC_MD5_Final>
      MessageDigestMD5;
  typedef MessageDigestBase<CC_SHA1_DIGEST_LENGTH, CC_SHA1_CTX, CC_SHA1_Init,
                            CC_SHA1_Update, CC_SHA1_Final>
      MessageDigestSHA1;
  typedef MessageDigestBase<CC_SHA224_DIGEST_LENGTH, CC_SHA256_CTX,
                            CC_SHA224_Init, CC_SHA224_Update, CC_SHA224_Final>
      MessageDigestSHA224;
  typedef MessageDigestBase<CC_SHA256_DIGEST_LENGTH, CC_SHA256_CTX,
                            CC_SHA256_Init, CC_SHA256_Update, CC_SHA256_Final>
      MessageDigestSHA256;
  typedef MessageDigestBase<CC_SHA384_DIGEST_LENGTH, CC_SHA512_CTX,
                            CC_SHA384_Init, CC_SHA384_Update, CC_SHA384_Final>
      MessageDigestSHA384;
  typedef MessageDigestBase<CC_SHA512_DIGEST_LENGTH, CC_SHA512_CTX,
                            CC_SHA512_Init, CC_SHA512_Update, CC_SHA512_Final>
      MessageDigestSHA512;
  
  } // namespace
  
  std::unique_ptr<MessageDigestImpl> MessageDigestImpl::sha1()
  {
    return make_unique<MessageDigestSHA1>();
  }
  
  MessageDigestImpl::hashes_t MessageDigestImpl::hashes = {
      {"sha-1", make_hi<MessageDigestSHA1>()},
      {"sha-224", make_hi<MessageDigestSHA224>()},
      {"sha-256", make_hi<MessageDigestSHA256>()},
      {"sha-384", make_hi<MessageDigestSHA384>()},
      {"sha-512", make_hi<MessageDigestSHA512>()},
      {"md5", make_hi<MessageDigestMD5>()},
      ADLER32_MESSAGE_DIGEST};
  
  } // namespace aria2
  