curl_darwinssl.c

    if(i % sizeof(u_int32_t) == 0)
      random_number = arc4random();
    entropy[i] = random_number & 0xFF;
    random_number >>= 8;
  }
  i = random_number = 0;
  (void)data;
}

void Curl_darwinssl_md5sum(unsigned char *tmp, /* input */
                           size_t tmplen,
                           unsigned char *md5sum, /* output */
                           size_t md5len)
{
  (void)md5len;
  (void)CC_MD5(tmp, (CC_LONG)tmplen, md5sum);
}

static ssize_t darwinssl_send(struct connectdata *conn,
                              int sockindex,
                              const void *mem,
                              size_t len,
                              CURLcode *curlcode)
{
  /*struct SessionHandle *data = conn->data;*/
  struct ssl_connect_data *connssl = &conn->ssl[sockindex];
  size_t processed = 0UL;
  OSStatus err;

  /* The SSLWrite() function works a little differently than expected. The
     fourth argument (processed) is currently documented in Apple's
     documentation as: "On return, the length, in bytes, of the data actually
     written."

     Now, one could interpret that as "written to the socket," but actually,
     it returns the amount of data that was written to a buffer internal to
     the SSLContextRef instead. So it's possible for SSLWrite() to return
     errSSLWouldBlock and a number of bytes "written" because those bytes were
     encrypted and written to a buffer, not to the socket.

     So if this happens, then we need to keep calling SSLWrite() over and
     over again with no new data until it quits returning errSSLWouldBlock. */

  /* Do we have buffered data to write from the last time we were called? */
  if(connssl->ssl_write_buffered_length) {
    /* Write the buffered data: */
    err = SSLWrite(connssl->ssl_ctx, NULL, 0UL, &processed);
    switch (err) {
      case noErr:
        /* processed is always going to be 0 because we didn't write to
           the buffer, so return how much was written to the socket */
        processed = connssl->ssl_write_buffered_length;
        connssl->ssl_write_buffered_length = 0UL;
        break;
      case errSSLWouldBlock: /* argh, try again */
        *curlcode = CURLE_AGAIN;
        return -1L;
      default:
        failf(conn->data, "SSLWrite() returned error %d", err);
        *curlcode = CURLE_SEND_ERROR;
        return -1L;
    }
  }
  else {
    /* We've got new data to write: */
    err = SSLWrite(connssl->ssl_ctx, mem, len, &processed);
    if(err != noErr) {
      switch (err) {
        case errSSLWouldBlock:
          /* Data was buffered but not sent, we have to tell the caller
             to try sending again, and remember how much was buffered */
          connssl->ssl_write_buffered_length = len;
          *curlcode = CURLE_AGAIN;
          return -1L;
        default:
          failf(conn->data, "SSLWrite() returned error %d", err);
          *curlcode = CURLE_SEND_ERROR;
          return -1L;
      }
    }
  }
  return (ssize_t)processed;
}

static ssize_t darwinssl_recv(struct connectdata *conn,
                              int num,
                              char *buf,
                              size_t buffersize,
                              CURLcode *curlcode)
{
  /*struct SessionHandle *data = conn->data;*/
  struct ssl_connect_data *connssl = &conn->ssl[num];
  size_t processed = 0UL;
  OSStatus err = SSLRead(connssl->ssl_ctx, buf, buffersize, &processed);

  if(err != noErr) {
    switch (err) {
      case errSSLWouldBlock:  /* return how much we read (if anything) */
        if(processed)
          return (ssize_t)processed;
        *curlcode = CURLE_AGAIN;
        return -1L;
        break;

      /* errSSLClosedGraceful - server gracefully shut down the SSL session
         errSSLClosedNoNotify - server hung up on us instead of sending a
           closure alert notice, read() is returning 0
         Either way, inform the caller that the server disconnected. */
      case errSSLClosedGraceful:
      case errSSLClosedNoNotify:
        *curlcode = CURLE_OK;
        return -1L;
        break;

      default:
        failf(conn->data, "SSLRead() return error %d", err);
        *curlcode = CURLE_RECV_ERROR;
        return -1L;
        break;
    }
  }
  return (ssize_t)processed;
}

#endif /* USE_DARWINSSL */