log_client.h

/* Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.

   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; version 2 of the License.

   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 */

#ifndef LOG_H_
#define LOG_H_

#include <stdio.h>
#include <iostream>
#include <sstream>

struct ldap_log_type
{
  typedef enum
  {
    LDAP_LOG_DBG, LDAP_LOG_INFO, LDAP_LOG_WARNING, LDAP_LOG_ERROR
  } ldap_type;
};


enum ldap_log_level
{
  LDAP_LOG_LEVEL_NONE= 1, LDAP_LOG_LEVEL_ERROR, LDAP_LOG_LEVEL_ERROR_WARNING, LDAP_LOG_LEVEL_ERROR_WARNING_INFO, LDAP_LOG_LEVEL_ALL
};


class Ldap_log_writer_error
{
public:
  Ldap_log_writer_error();
  ~Ldap_log_writer_error();
  void write(std::string data);
};


class Ldap_logger
{
public:
  Ldap_logger();
  ~Ldap_logger();
  template<ldap_log_type::ldap_type type>
  void log(std::string msg);
  void set_log_level(ldap_log_level level);

private:
  Ldap_log_writer_error *m_log_writer;
  ldap_log_level m_log_level;
};


template<ldap_log_type::ldap_type type>
void Ldap_logger::log(std::string msg)
{
  std::stringstream log_stream;
  switch (type)
  {
  case ldap_log_type::LDAP_LOG_DBG:
    if (LDAP_LOG_LEVEL_ALL > m_log_level)
    {
      return;
    }
    log_stream << "[DBG] ";
    break;
  case ldap_log_type::LDAP_LOG_INFO:
    if (LDAP_LOG_LEVEL_ERROR_WARNING_INFO > m_log_level)
    {
      return;
    }
    log_stream << "[Note] ";
    break;
  case ldap_log_type::LDAP_LOG_WARNING:
    if (LDAP_LOG_LEVEL_ERROR_WARNING > m_log_level)
    {
      return;
    }
    log_stream << "[Warning] ";
    break;
  case ldap_log_type::LDAP_LOG_ERROR:
    if (LDAP_LOG_LEVEL_NONE >= m_log_level)
    {
      return;
    }
    log_stream << "[Error] ";
    break;
  };

  /** We can write debug messages also in error log file if logging level is set to debug.
      For MySQL client this will come from environment variable */
  if (m_log_writer)
  {
    log_stream << ": " << msg;
    m_log_writer->write(log_stream.str());
  }
}


extern Ldap_logger *g_logger_client;

#define log_dbg g_logger_client->log< ldap_log_type::LDAP_LOG_DBG >
#define log_info g_logger_client->log< ldap_log_type::LDAP_LOG_INFO >
#define log_warning g_logger->log< ldap_log_type::LDAP_LOG_WARNING >
#define log_error g_logger_client->log< ldap_log_type::LDAP_LOG_ERROR >

#endif