/* Copyright (c) 2005, 2013, 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 St, Fifth Floor, Boston, MA 02110-1301  USA */

#ifndef LOG_H
#define LOG_H

#include "unireg.h"                    // REQUIRED: for other includes

/**
  the struct aggregates two paramenters that identify an event
  uniquely in scope of communication of a particular master and slave couple.
  I.e there can not be 2 events from the same staying connected master which
  have the same coordinates.
  @note
  Such identifier is not yet unique generally as the event originating master
  is resetable. Also the crashed master can be replaced with some other.
*/
typedef struct event_coordinates
{
  char * file_name; // binlog file name (directories stripped)
  my_off_t  pos;       // event's position in the binlog file
} LOG_POS_COORD;




/* log info errors */
#define LOG_INFO_EOF -1
#define LOG_INFO_IO  -2
#define LOG_INFO_INVALID -3
#define LOG_INFO_SEEK -4
#define LOG_INFO_MEM -6
#define LOG_INFO_FATAL -7
#define LOG_INFO_IN_USE -8
#define LOG_INFO_EMFILE -9


/* bitmap to SQL_LOG::close() */
#define LOG_CLOSE_INDEX		1
#define LOG_CLOSE_TO_BE_OPENED	2
#define LOG_CLOSE_STOP_EVENT	4

/* 
  Maximum unique log filename extension.
  Note: setting to 0x7FFFFFFF due to atol windows 
        overflow/truncate.
 */
#define MAX_LOG_UNIQUE_FN_EXT 0x7FFFFFFF

/* 
   Number of warnings that will be printed to error log
   before extension number is exhausted.
*/
#define LOG_WARN_UNIQUE_FN_EXT_LEFT 1000

#ifdef HAVE_PSI_INTERFACE
extern PSI_mutex_key key_LOG_INFO_lock;
#endif

/*
  Note that we destroy the lock mutex in the desctructor here.
  This means that object instances cannot be destroyed/go out of scope,
  until we have reset thd->current_linfo to NULL;
 */
typedef struct st_log_info
{
  char log_file_name[FN_REFLEN];
  my_off_t index_file_offset, index_file_start_offset;
  my_off_t pos;
  bool fatal; // if the purge happens to give us a negative offset
  int entry_index; //used in purge_logs(), calculatd in find_log_pos().
  mysql_mutex_t lock;
  st_log_info()
    : index_file_offset(0), index_file_start_offset(0),
      pos(0), fatal(0), entry_index(0)
    {
      log_file_name[0] = '\0';
      mysql_mutex_init(key_LOG_INFO_lock, &lock, MY_MUTEX_INIT_FAST);
    }
  ~st_log_info() { mysql_mutex_destroy(&lock);}
} LOG_INFO;

/*
  Currently we have only 3 kinds of logging functions: old-fashioned
  logs, stdout and csv logging routines.
*/
#define MAX_LOG_HANDLERS_NUM 3

/* log event handler flags */
#define LOG_NONE       1
#define LOG_FILE       2
#define LOG_TABLE      4

enum enum_log_type { LOG_UNKNOWN, LOG_NORMAL, LOG_BIN };
enum enum_log_state { LOG_OPENED, LOG_CLOSED, LOG_TO_BE_OPENED };

/*
  TODO use mmap instead of IO_CACHE for binlog
  (mmap+fsync is two times faster than write+fsync)
*/

class MYSQL_LOG
{
public:
  MYSQL_LOG();
  void init_pthread_objects();
  void cleanup();
  bool open(
#ifdef HAVE_PSI_INTERFACE
            PSI_file_key log_file_key,
#endif
            const char *log_name,
            enum_log_type log_type,
            const char *new_name,
            enum cache_type io_cache_type_arg,
            bool unique);
  bool init_and_set_log_file_name(const char *log_name,
                                  const char *new_name,
                                  enum_log_type log_type_arg,
                                  enum cache_type io_cache_type_arg,
                                  bool unique);
  void init(enum_log_type log_type_arg,
            enum cache_type io_cache_type_arg);
  void close(uint exiting);
  inline bool is_open() { return log_state != LOG_CLOSED; }
  const char *generate_name(const char *log_name, const char *suffix,
                            bool strip_ext, char *buff);
  int generate_new_name(char *new_name, const char *log_name, bool unique);
 protected:
  /* LOCK_log is inited by init_pthread_objects() */
  mysql_mutex_t LOCK_log;
  char *name;
  char log_file_name[FN_REFLEN];
  char time_buff[20], db[NAME_LEN + 1];
  bool write_error, inited;
  IO_CACHE log_file;
  enum_log_type log_type;
  volatile enum_log_state log_state;
  enum cache_type io_cache_type;
  friend class Log_event;
  ulong cur_log_ext;
#ifdef HAVE_PSI_INTERFACE
  /** Instrumentation key to use for file io in @c log_file */
  PSI_file_key m_log_file_key;
  /** The instrumentation key to use for @ LOCK_log. */
  PSI_mutex_key m_key_LOCK_log;
#endif
  int purge_up_to(ulong to_ext, const char *log_name);
};


enum enum_general_log_table_field
{
  GLT_FIELD_EVENT_TIME = 0,
  GLT_FIELD_USER_HOST,
  GLT_FIELD_THREAD_ID,
  GLT_FIELD_SERVER_ID,
  GLT_FIELD_COMMAND_TYPE,
  GLT_FIELD_ARGUMENT,
  GLT_FIELD_COUNT
};


class MYSQL_QUERY_LOG: public MYSQL_LOG
{
public:
  MYSQL_QUERY_LOG() : last_time(0) {}
  void reopen_file();
  bool write(time_t event_time, const char *user_host,
             uint user_host_len, my_thread_id thread_id,
             const char *command_type, uint command_type_len,
             const char *sql_text, uint sql_text_len);
  bool write(THD *thd, ulonglong current_time, time_t query_start_arg,
             const char *user_host, uint user_host_len,
             ulonglong query_utime, ulonglong lock_utime, bool is_command,
             const char *sql_text, uint sql_text_len);
  bool open_query_log(const char *log_name)
  {
    char buf[FN_REFLEN];
    return open(
#ifdef HAVE_PSI_INTERFACE
                key_file_query_log,
#endif
                generate_name(log_name, ".log", 0, buf),
                LOG_NORMAL, 0, WRITE_CACHE, false);
  }
  int rotate(ulong max_size, bool *need_purge);
  int new_file();

private:
  time_t last_time;
};

class Log_event_handler
{
public:
  Log_event_handler() {}
  virtual bool init()= 0;
  virtual void cleanup()= 0;

  virtual bool log_error(enum loglevel level, const char *format,
                         va_list args)= 0;
  virtual bool log_general(THD *thd, time_t event_time, const char *user_host,
                           uint user_host_len, my_thread_id thread_id,
                           const char *command_type, uint command_type_len,
                           const char *sql_text, uint sql_text_len,
                           const CHARSET_INFO *client_cs)= 0;
  virtual ~Log_event_handler() {}
};


int check_if_log_table(size_t db_len, const char *db, size_t table_name_len,
                       const char *table_name, bool check_if_opened);

class Log_to_csv_event_handler: public Log_event_handler
{
public:
  Log_to_csv_event_handler();
  ~Log_to_csv_event_handler();
  virtual bool init();
  virtual void cleanup();

  virtual bool log_error(enum loglevel level, const char *format,
                         va_list args);
  virtual bool log_general(THD *thd, time_t event_time, const char *user_host,
                           uint user_host_len, my_thread_id thread_id,
                           const char *command_type, uint command_type_len,
                           const char *sql_text, uint sql_text_len,
                           const CHARSET_INFO *client_cs);

  int activate_log(THD *thd, uint log_type);
};


/* type of the log table */
#define QUERY_LOG_SLOW 1
#define QUERY_LOG_GENERAL 2

class Log_to_file_event_handler: public Log_event_handler
{
  MYSQL_QUERY_LOG mysql_log;
  bool is_initialized;
public:
  Log_to_file_event_handler(): is_initialized(FALSE)
  {}
  virtual bool init();
  virtual void cleanup();

  virtual bool log_error(enum loglevel level, const char *format,
                         va_list args);
  virtual bool log_general(THD *thd, time_t event_time, const char *user_host,
                           uint user_host_len, my_thread_id thread_id,
                           const char *command_type, uint command_type_len,
                           const char *sql_text, uint sql_text_len,
                           const CHARSET_INFO *client_cs);
  void flush();
  void init_pthread_objects();
  MYSQL_QUERY_LOG *get_mysql_log() { return &mysql_log; }
};


/* Class which manages slow, general and error log event handlers */
class LOGGER
{
  mysql_rwlock_t LOCK_logger;
  /* flag to check whether logger mutex is initialized */
  uint inited;

  /* available log handlers */
  Log_to_file_event_handler *file_log_handler;

  /* NULL-terminated arrays of log handlers */
  Log_event_handler *error_log_handler_list[MAX_LOG_HANDLERS_NUM + 1];
  Log_event_handler *general_log_handler_list[MAX_LOG_HANDLERS_NUM + 1];

public:

  bool is_log_tables_initialized;

  LOGGER() : inited(0),
             file_log_handler(NULL), is_log_tables_initialized(FALSE)
  {}
  void lock_shared() { mysql_rwlock_rdlock(&LOCK_logger); }
  void lock_exclusive() { mysql_rwlock_wrlock(&LOCK_logger); }
  void unlock() { mysql_rwlock_unlock(&LOCK_logger); }
  bool is_log_table_enabled(uint log_table_type);
  bool log_command(THD *thd, enum enum_server_command command);

  /*
    We want to initialize all log mutexes as soon as possible,
    but we cannot do it in constructor, as safe_mutex relies on
    initialization, performed by MY_INIT(). This why this is done in
    this function.
  */
  void init_base();
  void init_log_tables();
  bool flush_logs(THD *thd);
  bool flush_general_log();
  /* Perform basic logger cleanup. this will leave e.g. error log open. */
  void cleanup_base();
  /* Free memory. Nothing could be logged after this function is called */
  void cleanup_end();
  bool error_log_print(enum loglevel level, const char *format,
                      va_list args);
  bool general_log_print(THD *thd,enum enum_server_command command,
                         const char *format, va_list args);
  bool general_log_write(THD *thd, enum enum_server_command command,
                         const char *query, uint query_length);

  /* we use this function to setup all enabled log event handlers */
  int set_handlers(uint error_log_printer,
                   uint general_log_printer);
  void init_error_log(uint error_log_printer);
  void init_general_log(uint general_log_printer);
  void deactivate_log_handler(THD* thd, uint log_type);
  bool activate_log_handler(THD* thd, uint log_type);

  MYSQL_QUERY_LOG *get_log_file_handler() const
  { 
    if (file_log_handler)
      return file_log_handler->get_mysql_log();
    return NULL;
  }
};

enum enum_binlog_row_image {
  /** PKE in the before image and changed columns in the after image */
  BINLOG_ROW_IMAGE_MINIMAL= 0,
  /** Whenever possible, before and after image contain all columns except blobs. */
  BINLOG_ROW_IMAGE_NOBLOB= 1,
  /** All columns in both before and after image. */
  BINLOG_ROW_IMAGE_FULL= 2
};

enum enum_binlog_format {
  BINLOG_FORMAT_MIXED= 0, ///< statement if safe, otherwise row - autodetected
  BINLOG_FORMAT_STMT=  1, ///< statement-based
  BINLOG_FORMAT_ROW=   2, ///< row-based
  BINLOG_FORMAT_UNSPEC=3  ///< thd_binlog_format() returns it when binlog is closed
};

int query_error_code(THD *thd, bool not_killed);
uint purge_log_get_error_code(int res);

int vprint_msg_to_log(enum loglevel level, const char *format, va_list args);
void sql_print_error(const char *format, ...) ATTRIBUTE_FORMAT(printf, 1, 2);
void sql_print_warning(const char *format, ...) ATTRIBUTE_FORMAT(printf, 1, 2);
void sql_print_information(const char *format, ...)
  ATTRIBUTE_FORMAT(printf, 1, 2);
typedef void (*sql_print_message_func)(const char *format, ...)
  ATTRIBUTE_FORMAT_FPTR(printf, 1, 2);
extern sql_print_message_func sql_print_message_handlers[];

int error_log_print(enum loglevel level, const char *format,
                    va_list args);

bool general_log_print(THD *thd, enum enum_server_command command,
                       const char *format,...);

bool general_log_write(THD *thd, enum enum_server_command command,
                       const char *query, uint query_length);

void sql_perror(const char *message);

char *make_log_name(char *buff, const char *name, const char* log_ext);

extern LOGGER logger;

#endif /* LOG_H */