storage/myisam/mi_extra.cc

/* Copyright (c) 2000, 2019, 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, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   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, version 2.0, 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 */

#include "my_config.h"

#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>

#include "my_dbug.h"
#include "my_inttypes.h"
#include "my_macros.h"
#include "storage/myisam/myisamdef.h"
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif

static void mi_extra_keyflag(MI_INFO *info, enum ha_extra_function function);

/*
  Set options and buffers to optimize table handling

  SYNOPSIS
    mi_extra()
    info	open table
    function	operation
    extra_arg	Pointer to extra argument (normally pointer to ulong)
                Not used.
  RETURN VALUES
    0  ok
    #  error
*/

int mi_extra(MI_INFO *info, enum ha_extra_function function, void *extra_arg) {
  int error = 0;
  MYISAM_SHARE *share = info->s;
  DBUG_TRACE;
  DBUG_PRINT("enter", ("function: %d", (int)function));

  switch (function) {
    case HA_EXTRA_RESET_STATE: /* Reset state (don't free buffers) */
      info->lastinx = 0;       /* Use first index as def */
      info->last_search_keypage = info->lastpos = HA_OFFSET_ERROR;
      info->page_changed = true;
      /* Next/prev gives first/last */
      if (info->opt_flag & READ_CACHE_USED) {
        reinit_io_cache(&info->rec_cache, READ_CACHE, 0,
                        (bool)(info->lock_type != F_UNLCK),
                        (bool)(info->update & HA_STATE_ROW_CHANGED));
      }
      info->update = ((info->update & HA_STATE_CHANGED) | HA_STATE_NEXT_FOUND |
                      HA_STATE_PREV_FOUND);
      break;
    case HA_EXTRA_PREPARE_FOR_UPDATE:
      if (info->s->data_file_type != DYNAMIC_RECORD) break;
      /* Remove read/write cache if dynamic rows */
      // Fall through.
    case HA_EXTRA_NO_READCHECK:
      info->opt_flag &= ~READ_CHECK_USED; /* No readcheck */
      break;
    case HA_EXTRA_READCHECK:
      info->opt_flag |= READ_CHECK_USED;
      break;
    case HA_EXTRA_KEYREAD: /* Read only keys to record */
    case HA_EXTRA_REMEMBER_POS:
      info->opt_flag |= REMEMBER_OLD_POS;
      memmove((uchar *)info->lastkey + share->base.max_key_length * 2,
              (uchar *)info->lastkey, info->lastkey_length);
      info->save_update = info->update;
      info->save_lastinx = info->lastinx;
      info->save_lastpos = info->lastpos;
      info->save_lastkey_length = info->lastkey_length;
      if (function == HA_EXTRA_REMEMBER_POS) break;
      /* fall through */
    case HA_EXTRA_KEYREAD_CHANGE_POS:
      info->opt_flag |= KEY_READ_USED;
      info->read_record = _mi_read_key_record;
      break;
    case HA_EXTRA_NO_KEYREAD:
    case HA_EXTRA_RESTORE_POS:
      if (info->opt_flag & REMEMBER_OLD_POS) {
        memmove((uchar *)info->lastkey,
                (uchar *)info->lastkey + share->base.max_key_length * 2,
                info->save_lastkey_length);
        info->update = info->save_update | HA_STATE_WRITTEN;
        info->lastinx = info->save_lastinx;
        info->lastpos = info->save_lastpos;
        info->lastkey_length = info->save_lastkey_length;
      }
      info->read_record = share->read_record;
      info->opt_flag &= ~(KEY_READ_USED | REMEMBER_OLD_POS);
      break;
    case HA_EXTRA_NO_USER_CHANGE: /* Database is somehow locked agains changes
                                   */
      info->lock_type = F_EXTRA_LCK; /* Simulate as locked */
      break;
    case HA_EXTRA_WAIT_LOCK:
      info->lock_wait = 0;
      break;
    case HA_EXTRA_NO_WAIT_LOCK:
      info->lock_wait = MY_DONT_WAIT;
      break;
    case HA_EXTRA_NO_KEYS:
      if (info->lock_type == F_UNLCK) {
        error = 1; /* Not possibly if not lock */
        break;
      }
      if (mi_is_any_key_active(share->state.key_map)) {
        MI_KEYDEF *key = share->keyinfo;
        uint i;
        for (i = 0; i < share->base.keys; i++, key++) {
          if (!(key->flag & HA_NOSAME) && info->s->base.auto_key != i + 1) {
            mi_clear_key_active(share->state.key_map, i);
            info->update |= HA_STATE_CHANGED;
          }
        }

        if (!share->changed) {
          share->state.changed |= STATE_CHANGED | STATE_NOT_ANALYZED;
          share->changed = true; /* Update on close */
          if (!share->global_changed) {
            share->global_changed = true;
            share->state.open_count++;
          }
        }
        share->state.state = *info->state;
        error = mi_state_info_write(share->kfile, &share->state, 1 | 2);
      }
      break;
    case HA_EXTRA_FORCE_REOPEN:
      mysql_mutex_lock(&THR_LOCK_myisam);
      share->last_version = 0L; /* Impossible version */
      mysql_mutex_unlock(&THR_LOCK_myisam);
      break;
    case HA_EXTRA_PREPARE_FOR_DROP:
      mysql_mutex_lock(&THR_LOCK_myisam);
      share->last_version = 0L; /* Impossible version */
      mysql_mutex_unlock(&THR_LOCK_myisam);
      break;
    case HA_EXTRA_FLUSH:
      if (!share->temporary)
        flush_key_blocks(share->key_cache, keycache_thread_var(), share->kfile,
                         FLUSH_KEEP);
#ifndef _WIN32
      _mi_decrement_open_count(info);
#endif
      if (share->not_flushed) {
        share->not_flushed = false;
        if (mysql_file_sync(share->kfile, MYF(0))) error = my_errno();
        if (mysql_file_sync(info->dfile, MYF(0))) error = my_errno();
        if (error) {
          share->changed = true;
          mi_print_error(info->s, HA_ERR_CRASHED);
          mi_mark_crashed(info); /* Fatal error found */
        }
      }
      if (share->base.blobs) mi_alloc_rec_buff(info, -1, &info->rec_buff);
      break;
    case HA_EXTRA_NORMAL: /* Theese isn't in use */
      info->quick_mode = false;
      break;
    case HA_EXTRA_QUICK:
      info->quick_mode = true;
      break;
    case HA_EXTRA_NO_ROWS:
      if (!share->state.header.uniques) info->opt_flag |= OPT_NO_ROWS;
      break;
    case HA_EXTRA_PRELOAD_BUFFER_SIZE:
      info->preload_buff_size = *((ulong *)extra_arg);
      break;
    case HA_EXTRA_CHANGE_KEY_TO_UNIQUE:
    case HA_EXTRA_CHANGE_KEY_TO_DUP:
      mi_extra_keyflag(info, function);
      break;
    case HA_EXTRA_MARK_AS_LOG_TABLE:
      mysql_mutex_lock(&share->intern_lock);
      share->is_log_table = true;
      mysql_mutex_unlock(&share->intern_lock);
      break;
    default:
      break;
  }
  {
    char tmp[1];
    tmp[0] = function;
    myisam_log_command(MI_LOG_EXTRA, info, (uchar *)tmp, 1, error);
  }
  return error;
} /* mi_extra */

void mi_set_index_cond_func(MI_INFO *info, index_cond_func_t func,
                            void *func_arg) {
  info->index_cond_func = func;
  info->index_cond_func_arg = func_arg;
}

/*
    Start/Stop Inserting Duplicates Into a Table, WL#1648.
 */
static void mi_extra_keyflag(MI_INFO *info, enum ha_extra_function function) {
  uint idx;

  for (idx = 0; idx < info->s->base.keys; idx++) {
    switch (function) {
      case HA_EXTRA_CHANGE_KEY_TO_UNIQUE:
        info->s->keyinfo[idx].flag |= HA_NOSAME;
        break;
      case HA_EXTRA_CHANGE_KEY_TO_DUP:
        info->s->keyinfo[idx].flag &= ~(HA_NOSAME);
        break;
      default:
        break;
    }
  }
}

int mi_reset(MI_INFO *info) {
  int error = 0;
  MYISAM_SHARE *share = info->s;
  DBUG_TRACE;
  /*
    Free buffers and reset the following flags:
    EXTRA_CACHE, EXTRA_WRITE_CACHE, EXTRA_KEYREAD, EXTRA_QUICK

    If the row buffer cache is large (for dynamic tables), reduce it
    to save memory.
  */
  if (info->opt_flag & (READ_CACHE_USED | WRITE_CACHE_USED)) {
    info->opt_flag &= ~(READ_CACHE_USED | WRITE_CACHE_USED);
    error = end_io_cache(&info->rec_cache);
  }
  if (share->base.blobs) mi_alloc_rec_buff(info, -1, &info->rec_buff);
#if defined(HAVE_MADVISE)
  if (info->opt_flag & MEMMAP_USED)
    madvise((char *)share->file_map, share->state.state.data_file_length,
            MADV_RANDOM);
#endif
  info->opt_flag &= ~(KEY_READ_USED | REMEMBER_OLD_POS);
  info->quick_mode = false;
  info->lastinx = 0; /* Use first index as def */
  info->last_search_keypage = info->lastpos = HA_OFFSET_ERROR;
  info->page_changed = true;
  info->update = ((info->update & HA_STATE_CHANGED) | HA_STATE_NEXT_FOUND |
                  HA_STATE_PREV_FOUND);
  return error;
}