/*
   Copyright (c) 2000, 2021, Oracle and/or its affiliates.

   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 */

/* Update an old row in a MyISAM table */

#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/fulltext.h"
#include "storage/myisam/myisamdef.h"
#include "storage/myisam/rt_index.h"

int mi_update(MI_INFO *info, const uchar *oldrec, uchar *newrec) {
  int flag, key_changed, save_errno;
  my_off_t pos;
  uint i;
  uchar old_key[MI_MAX_KEY_BUFF], *new_key;
  bool auto_key_changed = false;
  ulonglong changed;
  MYISAM_SHARE *share = info->s;
  ha_checksum old_checksum = 0;
  DBUG_TRACE;

  DBUG_EXECUTE_IF("myisam_pretend_crashed_table_on_usage",
                  mi_print_error(info->s, HA_ERR_CRASHED);
                  set_my_errno(HA_ERR_CRASHED); return HA_ERR_CRASHED;);
  if (!(info->update & HA_STATE_AKTIV)) {
    set_my_errno(HA_ERR_KEY_NOT_FOUND);
    return HA_ERR_KEY_NOT_FOUND;
  }
  if (share->options & HA_OPTION_READ_ONLY_DATA) {
    set_my_errno(EACCES);
    return EACCES;
  }
  if (info->state->key_file_length >= share->base.margin_key_file_length) {
    set_my_errno(HA_ERR_INDEX_FILE_FULL);
    return HA_ERR_INDEX_FILE_FULL;
  }
  pos = info->lastpos;
  if (_mi_readinfo(info, F_WRLCK, 1)) return my_errno();

  if (share->calc_checksum)
    old_checksum = info->checksum = (*share->calc_checksum)(info, oldrec);
  if ((*share->compare_record)(info, oldrec)) {
    save_errno = my_errno();
    goto err_end; /* Record has changed */
  }

  /* Calculate and check all unique constraints */
  key_changed = 0;
  for (i = 0; i < share->state.header.uniques; i++) {
    MI_UNIQUEDEF *def = share->uniqueinfo + i;
    if (mi_unique_comp(def, newrec, oldrec, true) &&
        mi_check_unique(info, def, newrec, mi_unique_hash(def, newrec),
                        info->lastpos)) {
      save_errno = my_errno();
      goto err_end;
    }
  }
  if (_mi_mark_file_changed(info)) {
    save_errno = my_errno();
    goto err_end;
  }

  /* Check which keys changed from the original row */

  new_key = info->lastkey2;
  changed = 0;
  for (i = 0; i < share->base.keys; i++) {
    if (mi_is_key_active(share->state.key_map, i)) {
      if (share->keyinfo[i].flag & HA_FULLTEXT) {
        if (_mi_ft_cmp(info, i, oldrec, newrec)) {
          if ((int)i == info->lastinx) {
            /*
              We are changeing the index we are reading on.  Mark that
              the index data has changed and we need to do a full search
              when doing read-next
            */
            key_changed |= HA_STATE_WRITTEN;
          }
          changed |= ((ulonglong)1 << i);
          if (_mi_ft_update(info, i, old_key, oldrec, newrec, pos)) goto err;
        }
      } else {
        uint new_length = _mi_make_key(info, i, new_key, newrec, pos);
        uint old_length = _mi_make_key(info, i, old_key, oldrec, pos);

        if (new_length != old_length ||
            memcmp((uchar *)old_key, (uchar *)new_key, new_length)) {
          if ((int)i == info->lastinx)
            key_changed |= HA_STATE_WRITTEN; /* Mark that keyfile changed */
          changed |= ((ulonglong)1 << i);
          share->keyinfo[i].version++;
          if (share->keyinfo[i].ck_delete(info, i, old_key, old_length))
            goto err;
          if (share->keyinfo[i].ck_insert(info, i, new_key, new_length))
            goto err;
          if (share->base.auto_key == i + 1) auto_key_changed = true;
        }
      }
    }
  }
  /*
    If we are running with external locking, we must update the index file
    that something has changed.
  */
  if (changed || !my_disable_locking) key_changed |= HA_STATE_CHANGED;

  if (share->calc_checksum) {
    info->checksum = (*share->calc_checksum)(info, newrec);
    /* Store new checksum in index file header */
    key_changed |= HA_STATE_CHANGED;
  }
  {
    /*
      Don't update index file if data file is not extended and no status
      information changed
    */
    MI_STATUS_INFO state;
    ha_rows org_split;
    my_off_t org_delete_link;

    memcpy((char *)&state, (char *)info->state, sizeof(state));
    org_split = share->state.split;
    org_delete_link = share->state.dellink;
    if ((*share->update_record)(info, pos, newrec)) goto err;
    if (!key_changed &&
        (memcmp((char *)&state, (char *)info->state, sizeof(state)) ||
         org_split != share->state.split ||
         org_delete_link != share->state.dellink))
      key_changed |= HA_STATE_CHANGED; /* Must update index file */
  }
  if (auto_key_changed)
    info->s->state.auto_increment = std::max(
        info->s->state.auto_increment, retrieve_auto_increment(info, newrec));
  if (share->calc_checksum)
    info->state->checksum += (info->checksum - old_checksum);

  info->update =
      (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED | HA_STATE_AKTIV | key_changed);
  myisam_log_record(MI_LOG_UPDATE, info, newrec, info->lastpos, 0);
  /*
    Every myisam function that updates myisam table must end with
    call to _mi_writeinfo(). If operation (second param of
    _mi_writeinfo()) is not 0 it sets share->changed to 1, that is
    flags that data has changed. If operation is 0, this function
    equals to no-op in this case.

    mi_update() must always pass !0 value as operation, since even if
    there is no index change there could be data change.
  */
  (void)_mi_writeinfo(info, WRITEINFO_UPDATE_KEYFILE);
  return 0;

err:
  DBUG_PRINT("error", ("key: %d  errno: %d", i, my_errno()));
  save_errno = my_errno();
  if (changed) key_changed |= HA_STATE_CHANGED;
  if (my_errno() == HA_ERR_FOUND_DUPP_KEY ||
      my_errno() == HA_ERR_RECORD_FILE_FULL ||
      my_errno() == HA_ERR_NULL_IN_SPATIAL || my_errno() == HA_ERR_OUT_OF_MEM) {
    info->errkey = (int)i;
    flag = 0;
    do {
      if (((ulonglong)1 << i) & changed) {
        if (share->keyinfo[i].flag & HA_FULLTEXT) {
          if ((flag++ && _mi_ft_del(info, i, new_key, newrec, pos)) ||
              _mi_ft_add(info, i, old_key, oldrec, pos))
            break;
        } else {
          uint new_length = _mi_make_key(info, i, new_key, newrec, pos);
          uint old_length = _mi_make_key(info, i, old_key, oldrec, pos);
          if ((flag++ &&
               share->keyinfo[i].ck_delete(info, i, new_key, new_length)) ||
              share->keyinfo[i].ck_insert(info, i, old_key, old_length))
            break;
        }
      }
    } while (i-- != 0);
  } else {
    mi_print_error(info->s, HA_ERR_CRASHED);
    mi_mark_crashed(info);
  }
  info->update =
      (HA_STATE_CHANGED | HA_STATE_AKTIV | HA_STATE_ROW_CHANGED | key_changed);

err_end:
  myisam_log_record(MI_LOG_UPDATE, info, newrec, info->lastpos, my_errno());
  (void)_mi_writeinfo(info, WRITEINFO_UPDATE_KEYFILE);
  if (save_errno == HA_ERR_KEY_NOT_FOUND) {
    mi_print_error(info->s, HA_ERR_CRASHED);
    save_errno = HA_ERR_CRASHED;
  }
  set_my_errno(save_errno);
  return save_errno;
} /* mi_update */
