text: /* Copyright 2008-2015 Codership Oy <http://www.codership.com>
  
     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 02111-1301 USA */
  
  #include "mariadb.h"
  #include <mysqld.h>
  #include "sql_base.h"
  #include "rpl_filter.h"
  #include <sql_class.h>
  #include "wsrep_mysqld.h"
  #include "wsrep_binlog.h"
  #include "wsrep_xid.h"
  #include <cstdio>
  #include <cstdlib>
  #include "debug_sync.h"
  
  extern ulonglong thd_to_trx_id(THD *thd);
  
  extern "C" int thd_binlog_format(const MYSQL_THD thd);
  // todo: share interface with ha_innodb.c
  
  /*
    Cleanup after local transaction commit/rollback, replay or TOI.
  */
  void wsrep_cleanup_transaction(THD *thd)
  {
    if (!WSREP(thd)) return;
  
    if (wsrep_emulate_bin_log) thd_binlog_trx_reset(thd);
    thd->wsrep_ws_handle.trx_id= WSREP_UNDEFINED_TRX_ID;
    thd->wsrep_trx_meta.gtid= WSREP_GTID_UNDEFINED;
    thd->wsrep_trx_meta.depends_on= WSREP_SEQNO_UNDEFINED;
    thd->wsrep_exec_mode= LOCAL_STATE;
    thd->wsrep_affected_rows= 0;
    thd->wsrep_skip_wsrep_GTID= false;
    return;
  }
  
  /*
    wsrep hton
  */
  handlerton *wsrep_hton;
  
  
  /*
    Registers wsrep hton at commit time if transaction has registered htons
    for supported engine types.
  
    Hton should not be registered for TOTAL_ORDER operations.
  
    Registration is needed for both LOCAL_MODE and REPL_RECV transactions to run
    commit in 2pc so that wsrep position gets properly recorded in storage
    engines.
  
    Note that all hton calls should immediately return for threads that are
    in REPL_RECV mode as their states are controlled by wsrep appliers or
    replaying code. Only threads in LOCAL_MODE should run wsrep callbacks
    from hton methods.
  */
  void wsrep_register_hton(THD* thd, bool all)
  {
    if (WSREP(thd) && thd->wsrep_exec_mode != TOTAL_ORDER &&
        !thd->wsrep_apply_toi)
    {
      if (thd->wsrep_exec_mode == LOCAL_STATE      &&
          (thd_sql_command(thd) == SQLCOM_OPTIMIZE ||
          thd_sql_command(thd) == SQLCOM_ANALYZE   ||
          thd_sql_command(thd) == SQLCOM_REPAIR)   &&
              thd->lex->no_write_to_binlog == 1)
      {
          WSREP_DEBUG("Skipping wsrep_register_hton for LOCAL sql admin command : %s",
                  thd->query());
          return;
      }
  
      THD_TRANS *trans=all ? &thd->transaction.all : &thd->transaction.stmt;
      for (Ha_trx_info *i= trans->ha_list; i; i = i->next())
      {
        if ((i->ht()->db_type == DB_TYPE_INNODB) ||
  	  (i->ht()->db_type == DB_TYPE_TOKUDB))
        {
          trans_register_ha(thd, all, wsrep_hton);
  
          /* follow innodb read/write settting
           * but, as an exception: CTAS with empty result set will not be
           * replicated unless we declare wsrep hton as read/write here
  	 */
          if (i->is_trx_read_write() ||
              ((thd->lex->sql_command == SQLCOM_CREATE_TABLE ||
                thd->lex->sql_command == SQLCOM_CREATE_SEQUENCE) &&
               thd->wsrep_exec_mode == LOCAL_STATE))
          {
            thd->ha_data[wsrep_hton->slot].ha_info[all].set_trx_read_write();
          }
          break;
        }
      }
    }
  }
  
  /*
    Calls wsrep->post_commit() for locally executed transactions that have
    got seqno from provider (must commit) and don't require replaying.
   */
  void wsrep_post_commit(THD* thd, bool all)
  {
    if (!WSREP(thd)) return;
  
    switch (thd->wsrep_exec_mode)
    {
      case LOCAL_COMMIT:
      {
        DBUG_ASSERT(thd->wsrep_trx_meta.gtid.seqno != WSREP_SEQNO_UNDEFINED);
        if (wsrep && wsrep->post_commit(wsrep, &thd->wsrep_ws_handle))
        {
          DBUG_PRINT("wsrep", ("set committed fail"));
          WSREP_WARN("set committed fail: %llu %d",
                     (long long)thd->real_id, thd->get_stmt_da()->status());
        }
        wsrep_cleanup_transaction(thd);
        break;
      }
      case LOCAL_STATE:
      {
        /* non-InnoDB statements may have populated events in stmt cache
          => cleanup
        */
        WSREP_DEBUG("cleanup transaction for LOCAL_STATE");
        /*
          Run post-rollback hook to clean up in the case if
          some keys were populated for the transaction in provider
          but during commit time there was no write set to replicate.
          This may happen when client sets the SAVEPOINT and immediately
          rolls back to savepoint after first operation.
        */
        if (all && thd->wsrep_conflict_state != MUST_REPLAY &&
            wsrep && wsrep->post_rollback(wsrep, &thd->wsrep_ws_handle))
        {
          WSREP_WARN("post_rollback fail: %llu %d",
  		(long long)thd->thread_id, thd->get_stmt_da()->status());
        }
        wsrep_cleanup_transaction(thd);
        break;
      }
      default: break;
    }
  }
  
  /*
    wsrep exploits binlog's caches even if binlogging itself is not
    activated. In such case connection close needs calling
    actual binlog's method.
    Todo: split binlog hton from its caches to use ones by wsrep
    without referring to binlog's stuff.
  */
  static int
  wsrep_close_connection(handlerton*  hton, THD* thd)
  {
    DBUG_ENTER("wsrep_close_connection");
  
    if (thd->wsrep_exec_mode == REPL_RECV)
    {
      DBUG_RETURN(0);
    }
    DBUG_RETURN(wsrep_binlog_close_connection (thd));
  }
  
  /*
    prepare/wsrep_run_wsrep_commit can fail in two ways
    - certification test or an equivalent. As a result,
      the current transaction just rolls back
      Error codes:
             WSREP_TRX_CERT_FAIL, WSREP_TRX_SIZE_EXCEEDED, WSREP_TRX_ERROR
    - a post-certification failure makes this server unable to
      commit its own WS and therefore the server must abort
  */
  static int wsrep_prepare(handlerton *hton, THD *thd, bool all)
  {
    DBUG_ENTER("wsrep_prepare");
  
    if (thd->wsrep_exec_mode == REPL_RECV)
    {
      DBUG_RETURN(0);
    }
  
    DBUG_ASSERT(thd->ha_data[wsrep_hton->slot].ha_info[all].is_trx_read_write());
    DBUG_ASSERT(thd->wsrep_exec_mode == LOCAL_STATE);
    DBUG_ASSERT(thd->wsrep_trx_meta.gtid.seqno == WSREP_SEQNO_UNDEFINED);
  
    if ((all ||
        !thd_test_options(thd, OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN)) &&
        (thd->variables.wsrep_on && !wsrep_trans_cache_is_empty(thd)))
    {
      int res= wsrep_run_wsrep_commit(thd, all);
      if (res != 0)
      {
        if (res == WSREP_TRX_SIZE_EXCEEDED)
          res= EMSGSIZE;
        else
          res= EDEADLK;                           // for a better error message
      }
      DBUG_RETURN (res);
    }
    DBUG_RETURN(0);
  }
  
  static int wsrep_savepoint_set(handlerton *hton, THD *thd,  void *sv)
  {
    DBUG_ENTER("wsrep_savepoint_set");
  
    if (thd->wsrep_exec_mode == REPL_RECV)
    {
      DBUG_RETURN(0);
    }
  
    if (!wsrep_emulate_bin_log) DBUG_RETURN(0);
    int rcode = wsrep_binlog_savepoint_set(thd, sv);
    DBUG_RETURN(rcode);
  }
  
  static int wsrep_savepoint_rollback(handlerton *hton, THD *thd, void *sv)
  {
    DBUG_ENTER("wsrep_savepoint_rollback");
  
    if (thd->wsrep_exec_mode == REPL_RECV)
    {
      DBUG_RETURN(0);
    }
  
    if (!wsrep_emulate_bin_log) DBUG_RETURN(0);
    int rcode = wsrep_binlog_savepoint_rollback(thd, sv);
    DBUG_RETURN(rcode);
  }
  
  static int wsrep_rollback(handlerton *hton, THD *thd, bool all)
  {
    DBUG_ENTER("wsrep_rollback");
  
    if (thd->wsrep_exec_mode == REPL_RECV)
    {
      DBUG_RETURN(0);
    }
  
    mysql_mutex_lock(&thd->LOCK_thd_data);
    switch (thd->wsrep_exec_mode)
    {
    case TOTAL_ORDER:
    case REPL_RECV:
        mysql_mutex_unlock(&thd->LOCK_thd_data);
        WSREP_DEBUG("Avoiding wsrep rollback for failed DDL: %s", thd->query());
        DBUG_RETURN(0);
    default: break;
    }
  
    if ((all || !thd_test_options(thd, OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN)) &&
        (thd->variables.wsrep_on && thd->wsrep_conflict_state != MUST_REPLAY))
    {
      if (wsrep && wsrep->post_rollback(wsrep, &thd->wsrep_ws_handle))
      {
        DBUG_PRINT("wsrep", ("setting rollback fail"));
        WSREP_ERROR("settting rollback fail: thd: %llu, schema: %s, SQL: %s",
                    (long long)thd->real_id, thd->get_db(), thd->query());
      }
      wsrep_cleanup_transaction(thd);
    }
    mysql_mutex_unlock(&thd->LOCK_thd_data);
    DBUG_RETURN(0);
  }
  
  int wsrep_commit(handlerton *hton, THD *thd, bool all)
  {
    DBUG_ENTER("wsrep_commit");
  
    if (thd->wsrep_exec_mode == REPL_RECV)
    {
      DBUG_RETURN(0);
    }
  
    mysql_mutex_lock(&thd->LOCK_thd_data);
    if ((all || !thd_test_options(thd, OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN)) &&
        (thd->variables.wsrep_on && thd->wsrep_conflict_state != MUST_REPLAY))
    {
      if (thd->wsrep_exec_mode == LOCAL_COMMIT)
      {
        DBUG_ASSERT(thd->ha_data[wsrep_hton->slot].ha_info[all].is_trx_read_write());
        /*
          Call to wsrep->post_commit() (moved to wsrep_post_commit()) must
          be done only after commit has done for all involved htons.
        */
        DBUG_PRINT("wsrep", ("commit"));
      }
      else
      {
        /*
          Transaction didn't go through wsrep->pre_commit() so just roll back
          possible changes to clean state.
        */
        if (WSREP_PROVIDER_EXISTS) {
          if (wsrep && wsrep->post_rollback(wsrep, &thd->wsrep_ws_handle))
          {
            DBUG_PRINT("wsrep", ("setting rollback fail"));
            WSREP_ERROR("settting rollback fail: thd: %llu, schema: %s, SQL: %s",
                        (long long)thd->real_id, thd->get_db(),
                        thd->query());
          }
        }
        wsrep_cleanup_transaction(thd);
      }
    }
    mysql_mutex_unlock(&thd->LOCK_thd_data);
    DBUG_RETURN(0);
  }
  
  
  extern Rpl_filter* binlog_filter;
  extern my_bool opt_log_slave_updates;
  
  enum wsrep_trx_status
  wsrep_run_wsrep_commit(THD *thd, bool all)
  {
    int rcode= -1;
    size_t data_len= 0;
    IO_CACHE *cache;
    int replay_round= 0;
    DBUG_ENTER("wsrep_run_wsrep_commit");
  
    if (thd->get_stmt_da()->is_error()) {
      WSREP_DEBUG("commit issue, error: %d %s",
                  thd->get_stmt_da()->sql_errno(), thd->get_stmt_da()->message());
    }
  
    DEBUG_SYNC(thd, "wsrep_before_replication");
  
    if (thd->slave_thread && !opt_log_slave_updates) DBUG_RETURN(WSREP_TRX_OK);
  
    if (thd->wsrep_exec_mode == REPL_RECV) {
  
      mysql_mutex_lock(&thd->LOCK_thd_data);
      if (thd->wsrep_conflict_state == MUST_ABORT) {
        if (wsrep_debug)
          WSREP_INFO("WSREP: must abort for BF");
        DBUG_PRINT("wsrep", ("BF apply commit fail"));
        thd->wsrep_conflict_state = NO_CONFLICT;
        mysql_mutex_unlock(&thd->LOCK_thd_data);
        //
        // TODO: test all calls of the rollback.
        // rollback must happen automagically innobase_rollback(hton, thd, 1);
        //
        DBUG_RETURN(WSREP_TRX_ERROR);
      }
      mysql_mutex_unlock(&thd->LOCK_thd_data);
    }
  
    if (thd->wsrep_exec_mode != LOCAL_STATE) DBUG_RETURN(WSREP_TRX_OK);
  
    if (thd->wsrep_consistency_check == CONSISTENCY_CHECK_RUNNING) {
      WSREP_DEBUG("commit for consistency check: %s", thd->query());
      DBUG_RETURN(WSREP_TRX_OK);
    }
  
    DBUG_PRINT("wsrep", ("replicating commit"));
  
    mysql_mutex_lock(&thd->LOCK_thd_data);
    if (thd->wsrep_conflict_state == MUST_ABORT) {
      DBUG_PRINT("wsrep", ("replicate commit fail"));
      thd->wsrep_conflict_state = ABORTED;
      mysql_mutex_unlock(&thd->LOCK_thd_data);
      if (wsrep_debug) {
        WSREP_INFO("innobase_commit, abort %s",
                   (thd->query()) ? thd->query() : "void");
      }
      DBUG_RETURN(WSREP_TRX_CERT_FAIL);
    }
  
    mysql_mutex_lock(&LOCK_wsrep_replaying);
  
    DBUG_PRINT("info", ("wsrep_replaying: %d  wsrep_conflict_state: %d  killed: %d  shutdown_in_progress: %d",
                        (int) wsrep_replaying, (int) thd->wsrep_conflict_state,
                        (int) thd->killed,
                        (int) shutdown_in_progress));
  
    while (wsrep_replaying > 0                       &&
           thd->wsrep_conflict_state == NO_CONFLICT  &&
           thd->killed == NOT_KILLED            &&
           !shutdown_in_progress)
    {
  
      mysql_mutex_unlock(&LOCK_wsrep_replaying);
      mysql_mutex_unlock(&thd->LOCK_thd_data);
  
      mysql_mutex_lock(&thd->mysys_var->mutex);
      thd_proc_info(thd, "WSREP waiting on replaying");
      thd->mysys_var->current_mutex= &LOCK_wsrep_replaying;
      thd->mysys_var->current_cond=  &COND_wsrep_replaying;
      mysql_mutex_unlock(&thd->mysys_var->mutex);
  
      mysql_mutex_lock(&LOCK_wsrep_replaying);
      // Using timedwait is a hack to avoid deadlock in case if BF victim
      // misses the signal.
      struct timespec wtime = {0, 1000000};
      mysql_cond_timedwait(&COND_wsrep_replaying, &LOCK_wsrep_replaying,
  			 &wtime);
  
      if (replay_round++ % 100000 == 0)
        WSREP_DEBUG("commit waiting for replaying: replayers %d, thd: %lld "
                    "conflict: %d (round: %d)",
  		  wsrep_replaying, (longlong) thd->thread_id,
                    thd->wsrep_conflict_state, replay_round);
  
      mysql_mutex_unlock(&LOCK_wsrep_replaying);
  
      mysql_mutex_lock(&thd->mysys_var->mutex);
      thd->mysys_var->current_mutex= 0;
      thd->mysys_var->current_cond=  0;
      mysql_mutex_unlock(&thd->mysys_var->mutex);
  
      mysql_mutex_lock(&thd->LOCK_thd_data);
      mysql_mutex_lock(&LOCK_wsrep_replaying);
    }
    mysql_mutex_unlock(&LOCK_wsrep_replaying);
  
    if (thd->wsrep_conflict_state == MUST_ABORT) {
      DBUG_PRINT("wsrep", ("replicate commit fail"));
      thd->wsrep_conflict_state = ABORTED;
      mysql_mutex_unlock(&thd->LOCK_thd_data);
      WSREP_DEBUG("innobase_commit abort after replaying wait %s",
                  (thd->query()) ? thd->query() : "void");
      DBUG_RETURN(WSREP_TRX_CERT_FAIL);
    }
  
    thd->wsrep_query_state = QUERY_COMMITTING;
    mysql_mutex_unlock(&thd->LOCK_thd_data);
  
    cache = get_trans_log(thd);
    rcode = 0;
    if (cache) {
      thd->binlog_flush_pending_rows_event(true);
      rcode = wsrep_write_cache(wsrep, thd, cache, &data_len);
      if (WSREP_OK != rcode) {
        WSREP_ERROR("rbr write fail, data_len: %zu, %d", data_len, rcode);
        DBUG_RETURN(WSREP_TRX_SIZE_EXCEEDED);
      }
    }
  
    DBUG_PRINT("info", ("rcode: %d  wsrep_conflict_state: %d",
                        rcode, thd->wsrep_conflict_state));
  
    if (data_len == 0)
    {
      if (thd->get_stmt_da()->is_ok()              &&
          thd->get_stmt_da()->affected_rows() > 0  &&
          !binlog_filter->is_on())
      {
        WSREP_DEBUG("empty rbr buffer, query: %s, "
                   "affected rows: %llu, "
                   "changed tables: %d, "
                   "sql_log_bin: %d, "
                   "wsrep status (%d %d %d)",
                   thd->query(), thd->get_stmt_da()->affected_rows(),
                   stmt_has_updated_trans_table(thd), thd->variables.sql_log_bin,
                   thd->wsrep_exec_mode, thd->wsrep_query_state,
                   thd->wsrep_conflict_state);
      }
      else
      {
        WSREP_DEBUG("empty rbr buffer, query: %s", thd->query());
      }
      thd->wsrep_query_state= QUERY_EXEC;
      DBUG_RETURN(WSREP_TRX_OK);
    }
  
    if (WSREP_UNDEFINED_TRX_ID == thd->wsrep_ws_handle.trx_id)
    {
      WSREP_WARN("SQL statement was ineffective  thd: %lld  buf: %zu\n"
                 "schema: %s \n"
  	       "QUERY: %s\n"
  	       " => Skipping replication",
  	       (longlong) thd->thread_id, data_len,
                 thd->get_db(), thd->query());
      rcode = WSREP_TRX_FAIL;
    }
    else if (!rcode)
    {
      if (WSREP_OK == rcode && wsrep)
        rcode = wsrep->pre_commit(wsrep,
                                  (wsrep_conn_id_t)thd->thread_id,
                                  &thd->wsrep_ws_handle,
                                  WSREP_FLAG_COMMIT |
                                  ((thd->wsrep_PA_safe) ?
                                   0ULL : WSREP_FLAG_PA_UNSAFE),
                                  &thd->wsrep_trx_meta);
  
      DBUG_PRINT("info", ("rcode after pre_commit: %d", rcode));
  
      if (rcode == WSREP_TRX_MISSING) {
        WSREP_WARN("Transaction missing in provider, thd: %lld  schema: %s  SQL: %s",
                   (longlong) thd->thread_id,
                   thd->get_db(), thd->query());
        rcode = WSREP_TRX_FAIL;
      } else if (rcode == WSREP_BF_ABORT) {
        WSREP_DEBUG("thd: %lld  seqno: %lld  BF aborted by provider, will replay",
                    (longlong) thd->thread_id,
                    (longlong) thd->wsrep_trx_meta.gtid.seqno);
        mysql_mutex_lock(&thd->LOCK_thd_data);
        thd->wsrep_conflict_state = MUST_REPLAY;
        DBUG_ASSERT(wsrep_thd_trx_seqno(thd) > 0);
        mysql_mutex_unlock(&thd->LOCK_thd_data);
        mysql_mutex_lock(&LOCK_wsrep_replaying);
        wsrep_replaying++;
        WSREP_DEBUG("replaying increased: %d, thd: %lld",
                    wsrep_replaying, (longlong) thd->thread_id);
        mysql_mutex_unlock(&LOCK_wsrep_replaying);
      }
    } else {
      WSREP_ERROR("I/O error reading from thd's binlog iocache: "
                  "errno=%d, io cache code=%d", my_errno, cache->error);
      DBUG_ASSERT(0); // failure like this can not normally happen
      DBUG_RETURN(WSREP_TRX_ERROR);
    }
  
    mysql_mutex_lock(&thd->LOCK_thd_data);
  
    DEBUG_SYNC(thd, "wsrep_after_replication");
  
    DBUG_PRINT("info", ("rcode: %d  wsrep_conflict_state: %d",
                        rcode, thd->wsrep_conflict_state));
  
    switch(rcode) {
    case 0:
      /*
        About MUST_ABORT: We assume that even if thd conflict state was set
        to MUST_ABORT, underlying transaction was not rolled back or marked
        as deadlock victim in QUERY_COMMITTING state. Conflict state is
        set to NO_CONFLICT and commit proceeds as usual.
      */
      if (thd->wsrep_conflict_state == MUST_ABORT)
          thd->wsrep_conflict_state= NO_CONFLICT;
  
      if (thd->wsrep_conflict_state != NO_CONFLICT)
      {
        WSREP_WARN("thd: %llu  seqno: %lld  conflict state %d after post commit",
                   (longlong) thd->thread_id,
                   (longlong) thd->wsrep_trx_meta.gtid.seqno,
                   thd->wsrep_conflict_state);
      }
      thd->wsrep_exec_mode= LOCAL_COMMIT;
      DBUG_ASSERT(thd->wsrep_trx_meta.gtid.seqno != WSREP_SEQNO_UNDEFINED);
      /* Override XID iff it was generated by mysql */
      if (thd->transaction.xid_state.xid.get_my_xid())
      {
        wsrep_xid_init(&thd->transaction.xid_state.xid,
                       thd->wsrep_trx_meta.gtid.uuid,
                       thd->wsrep_trx_meta.gtid.seqno);
      }
      DBUG_PRINT("wsrep", ("replicating commit success"));
      break;
    case WSREP_BF_ABORT:
      DBUG_ASSERT(thd->wsrep_trx_meta.gtid.seqno != WSREP_SEQNO_UNDEFINED);
      /* fall through */
    case WSREP_TRX_FAIL:
      WSREP_DEBUG("commit failed for reason: %d", rcode);
      DBUG_PRINT("wsrep", ("replicating commit fail"));
  
      thd->wsrep_query_state= QUERY_EXEC;
  
      if (thd->wsrep_conflict_state == MUST_ABORT) {
        thd->wsrep_conflict_state= ABORTED;
      }
      else
      {
        WSREP_DEBUG("conflict state: %d", thd->wsrep_conflict_state);
        if (thd->wsrep_conflict_state == NO_CONFLICT)
        {
          thd->wsrep_conflict_state = CERT_FAILURE;
          WSREP_LOG_CONFLICT(NULL, thd, FALSE);
        }
      }
      mysql_mutex_unlock(&thd->LOCK_thd_data);
  
      DBUG_RETURN(WSREP_TRX_CERT_FAIL);
  
    case WSREP_SIZE_EXCEEDED:
      WSREP_ERROR("transaction size exceeded");
      mysql_mutex_unlock(&thd->LOCK_thd_data);
      DBUG_RETURN(WSREP_TRX_SIZE_EXCEEDED);
    case WSREP_CONN_FAIL:
      WSREP_ERROR("connection failure");
      mysql_mutex_unlock(&thd->LOCK_thd_data);
      DBUG_RETURN(WSREP_TRX_ERROR);
    default:
      WSREP_ERROR("unknown connection failure");
      mysql_mutex_unlock(&thd->LOCK_thd_data);
      DBUG_RETURN(WSREP_TRX_ERROR);
    }
  
    thd->wsrep_query_state= QUERY_EXEC;
    mysql_mutex_unlock(&thd->LOCK_thd_data);
  
    DBUG_RETURN(WSREP_TRX_OK);
  }
  
  
  static int wsrep_hton_init(void *p)
  {
    wsrep_hton= (handlerton *)p;
    //wsrep_hton->state=opt_bin_log ? SHOW_OPTION_YES : SHOW_OPTION_NO;
    wsrep_hton->state= SHOW_OPTION_YES;
    wsrep_hton->db_type=(legacy_db_type)0;
    wsrep_hton->savepoint_offset= sizeof(my_off_t);
    wsrep_hton->close_connection= wsrep_close_connection;
    wsrep_hton->savepoint_set= wsrep_savepoint_set;
    wsrep_hton->savepoint_rollback= wsrep_savepoint_rollback;
    wsrep_hton->commit= wsrep_commit;
    wsrep_hton->rollback= wsrep_rollback;
    wsrep_hton->prepare= wsrep_prepare;
    wsrep_hton->flags= HTON_NOT_USER_SELECTABLE | HTON_HIDDEN; // todo: fix flags
    return 0;
  }
  
  
  struct st_mysql_storage_engine wsrep_storage_engine=
  { MYSQL_HANDLERTON_INTERFACE_VERSION };
  
  
  maria_declare_plugin(wsrep)
  {
    MYSQL_STORAGE_ENGINE_PLUGIN,
    &wsrep_storage_engine,
    "wsrep",
    "Codership Oy",
    "A pseudo storage engine to represent transactions in multi-master "
    "synchornous replication",
    PLUGIN_LICENSE_GPL,
    wsrep_hton_init, /* Plugin Init */
    NULL, /* Plugin Deinit */
    0x0100 /* 1.0 */,
    NULL,                       /* status variables                */
    NULL,                       /* system variables                */
    "1.0",         /* string version */
    MariaDB_PLUGIN_MATURITY_STABLE /* maturity */
  }
  maria_declare_plugin_end;
  