Function get_40_protocol_string

phx_percona/percona/sql/sql_acl.cc:10447–10480

Get a string formatted according to the 4.0 version of the MySQL protocol. @param buffer[in, out] Pointer to the user-supplied buffer to be scanned. @param max_bytes_available[in, out] Limit the bytes to scan. @param string_length[out] The number of characters scanned not including the null character. @remark If there are not enough bytes left after the cu

          string.
*/
static
char *get_40_protocol_string(char **buffer,
                             size_t *max_bytes_available,
                             size_t *string_length)
{
  char *str;
  size_t len;

  /* No bytes to scan left, treat string as empty. */
  if ((*max_bytes_available) == 0)
  {
    *string_length= 0;
    return empty_c_string;
  }

  str= (char *) memchr(*buffer, '\0', *max_bytes_available);

  /*
    If the string was not null terminated by the client,
    the remainder of the packet is the string. Otherwise,
    advance the buffer past the end of the null terminated
    string.
  */
  if (str == NULL)
    len= *string_length= *max_bytes_available;
  else
    len= (*string_length= (size_t)(str - *buffer)) + 1;

  str= *buffer;
  *buffer+= len;
  *max_bytes_available-= len;

  return str;
}

/**
  Get a length encoded string from a user-supplied buffer.