mi_info.cc

/* Copyright (c) 2000, 2025, 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 designed to work 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 either included with
   the program or referenced in the documentation.

   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 */

/* Return useful base information for an open table */

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

#include "my_dbug.h"
#include "my_inttypes.h"
#include "storage/myisam/myisamdef.h"
#ifdef _WIN32
#include <sys/stat.h>
#endif

/* Get position to last record */

my_off_t mi_position(MI_INFO *info) { return info->lastpos; }

/* Get information about the table */
/* if flag == 2 one get current info (no sync from database */

int mi_status(MI_INFO *info, MI_ISAMINFO *x, uint flag) {
  MY_STAT state;
  MYISAM_SHARE *share = info->s;
  DBUG_TRACE;

  x->recpos = info->lastpos;
  if (flag == HA_STATUS_POS) return 0; /* Compatible with ISAM */
  if (!(flag & HA_STATUS_NO_LOCK)) {
    mysql_mutex_lock(&share->intern_lock);
    (void)_mi_readinfo(info, F_RDLCK, 0);
    fast_mi_writeinfo(info);
    mysql_mutex_unlock(&share->intern_lock);
  }
  if (flag & HA_STATUS_VARIABLE) {
    x->records = info->state->records;
    x->deleted = info->state->del;
    x->delete_length = info->state->empty;
    x->data_file_length = info->state->data_file_length;
    x->index_file_length = info->state->key_file_length;

    x->keys = share->state.header.keys;
    x->check_time = share->state.check_time;
    x->mean_reclength =
        x->records
            ? (ulong)((x->data_file_length - x->delete_length) / x->records)
            : (ulong)share->min_pack_length;
  }
  if (flag & HA_STATUS_ERRKEY) {
    x->errkey = info->errkey;
    x->dupp_key_pos = info->dupp_key_pos;
  }
  if (flag & HA_STATUS_CONST) {
    x->reclength = share->base.reclength;
    x->max_data_file_length = share->base.max_data_file_length;
    x->max_index_file_length = info->s->base.max_key_file_length;
    x->filenr = info->dfile;
    x->options = share->options;
    x->create_time = share->state.create_time;
    x->reflength = mi_get_pointer_length(share->base.max_data_file_length,
                                         myisam_data_pointer_size);
    x->record_offset =
        ((share->options & (HA_OPTION_PACK_RECORD | HA_OPTION_COMPRESS_RECORD))
             ? 0L
             : share->base.pack_reclength);
    x->sortkey = -1; /* No clustering */
    x->rec_per_key = share->state.rec_per_key_part;
    x->key_map = share->state.key_map;
    x->data_file_name = share->data_file_name;
    x->index_file_name = share->index_file_name;
  }
  if ((flag & HA_STATUS_TIME) && !mysql_file_fstat(info->dfile, &state))
    x->update_time = state.st_mtime;
  else
    x->update_time = 0;
  if (flag & HA_STATUS_AUTO) {
    x->auto_increment = share->state.auto_increment + 1;
    if (!x->auto_increment) /* This shouldn't happen */
      x->auto_increment = ~(ulonglong)0;
  }
  return 0;
}

/*
  Write a message to the error log.

  SYNOPSIS
    mi_report_error()
    file_name                   Name of table file (e.g. index_file_name).
    errcode                     Error number.

  DESCRIPTION
    This function supplies my_error() with a table name. Most error
    messages need one. Since string arguments in error messages are limited
    to 64 characters by convention, we ensure that in case of truncation,
    that the end of the index file path is in the message. This contains
    the most valuable information (the table name and the database name).

  RETURN
    void
*/

void mi_report_error(int errcode, const char *file_name) {
  size_t lgt;
  DBUG_TRACE;
  DBUG_PRINT("enter", ("errcode %d, table '%s'", errcode, file_name));

  if ((lgt = strlen(file_name)) > 64) file_name += lgt - 64;
  my_error(errcode, MYF(ME_ERRORLOG), file_name);
}