my_open.cc

/* Copyright (c) 2000, 2018, 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.

   Without limiting anything contained in the foregoing, this file,
   which is part of C Driver for MySQL (Connector/C), is also subject to the
   Universal FOSS Exception, version 1.0, a copy of which can be found at
   http://oss.oracle.com/licenses/universal-foss-exception.

   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 */

/**
  @file mysys/my_open.cc
*/

#include "my_config.h"

#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <sys/types.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "my_dbug.h"
#include "my_inttypes.h"
#include "my_io.h"
#include "my_sys.h"
#include "my_thread_local.h"
#include "mysql/psi/mysql_mutex.h"
#include "mysql/service_mysql_alloc.h"
#include "mysys/mysys_priv.h"
#include "mysys_err.h"

/*
  Open a file

  SYNOPSIS
    my_open()
      FileName	Fully qualified file name
      Flags	Read | write
      MyFlags	Special flags

  RETURN VALUE
    File descriptor
*/

File my_open(const char *FileName, int Flags, myf MyFlags)
/* Path-name of file */
/* Read | write .. */
/* Special flags */
{
  File fd;
  DBUG_ENTER("my_open");
  DBUG_PRINT("my",
             ("Name: '%s'  Flags: %d  MyFlags: %d", FileName, Flags, MyFlags));
#if defined(_WIN32)
  fd = my_win_open(FileName, Flags);
#else
  fd = open(FileName, Flags, my_umask); /* Normal unix */
#endif

  fd = my_register_filename(fd, FileName, FILE_BY_OPEN, EE_FILENOTFOUND,
                            MyFlags);
  DBUG_RETURN(fd);
} /* my_open */

/*
  Close a file

  SYNOPSIS
    my_close()
      fd	File sescriptor
      myf	Special Flags

*/

int my_close(File fd, myf MyFlags) {
  int err;
  DBUG_ENTER("my_close");
  DBUG_PRINT("my", ("fd: %d  MyFlags: %d", fd, MyFlags));

  mysql_mutex_lock(&THR_LOCK_open);
#ifndef _WIN32
  do {
    err = close(fd);
  } while (err == -1 && errno == EINTR);
#else
  err = my_win_close(fd);
#endif
  if (err) {
    DBUG_PRINT("error", ("Got error %d on close", err));
    set_my_errno(errno);
    if (MyFlags & (MY_FAE | MY_WME)) {
      char errbuf[MYSYS_STRERROR_SIZE];
      my_error(EE_BADCLOSE, MYF(0), my_filename(fd), my_errno(),
               my_strerror(errbuf, sizeof(errbuf), my_errno()));
    }
  }
  if ((uint)fd < my_file_limit && my_file_info[fd].type != UNOPEN) {
    my_free(my_file_info[fd].name);
    my_file_info[fd].type = UNOPEN;
  }
  my_file_opened--;
  mysql_mutex_unlock(&THR_LOCK_open);
  DBUG_RETURN(err);
} /* my_close */

/*
  Register file in my_file_info[]

  SYNOPSIS
    my_register_filename()
    fd			   File number opened, -1 if error on open
    FileName		   File name
    type_file_type	   How file was created
    error_message_number   Error message number if caller got error (fd == -1)
    MyFlags		   Flags for my_close()

  RETURN
    -1   error
     #   Filenumber

*/

File my_register_filename(File fd, const char *FileName,
                          enum file_type type_of_file,
                          uint error_message_number, myf MyFlags) {
  char *dup_filename = NULL;
  DBUG_ENTER("my_register_filename");
  if ((int)fd >= MY_FILE_MIN) {
    if ((uint)fd >= my_file_limit) {
#if defined(_WIN32)
      set_my_errno(EMFILE);
#else
      mysql_mutex_lock(&THR_LOCK_open);
      my_file_opened++;
      mysql_mutex_unlock(&THR_LOCK_open);
      DBUG_RETURN(fd); /* safeguard */
#endif
    } else {
      dup_filename = my_strdup(key_memory_my_file_info, FileName, MyFlags);
      if (dup_filename != NULL) {
        mysql_mutex_lock(&THR_LOCK_open);
        my_file_info[fd].name = dup_filename;
        my_file_opened++;
        my_file_total_opened++;
        my_file_info[fd].type = type_of_file;
        mysql_mutex_unlock(&THR_LOCK_open);
        DBUG_PRINT("exit", ("fd: %d", fd));
        DBUG_RETURN(fd);
      }
      set_my_errno(ENOMEM);
    }
    (void)my_close(fd, MyFlags);
  } else
    set_my_errno(errno);

  DBUG_PRINT("error", ("Got error %d on open", my_errno()));
  if (MyFlags & (MY_FFNF | MY_FAE | MY_WME)) {
    char errbuf[MYSYS_STRERROR_SIZE];
    if (my_errno() == EMFILE) error_message_number = EE_OUT_OF_FILERESOURCES;
    DBUG_PRINT("error", ("print err: %d", error_message_number));
    my_error(error_message_number, MYF(0), FileName, my_errno(),
             my_strerror(errbuf, sizeof(errbuf), my_errno()));
  }
  DBUG_RETURN(-1);
}

#ifdef EXTRA_DEBUG

void my_print_open_files(void) {
  if (my_file_opened | my_stream_opened) {
    uint i;
    for (i = 0; i < my_file_limit; i++) {
      if (my_file_info[i].type != UNOPEN) {
        my_message_local(INFORMATION_LEVEL, EE_FILE_NOT_CLOSED,
                         my_file_info[i].name, i);
      }
    }
  }
}

#endif