my_open.c

/* Copyright (c) 2000, 2011, 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 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 St, Fifth Floor, Boston, MA 02110-1301  USA */

#include "mysys_priv.h"
#include "mysys_err.h"
#include <my_dir.h>
#include <errno.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);
#elif !defined(NO_OPEN_3)
  fd = open(FileName, Flags, my_umask); /* Normal unix */
#else
  fd = open((char *) FileName, Flags);
#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));
    my_errno=errno;
    if (MyFlags & (MY_FAE | MY_WME))
    {
      char errbuf[MYSYS_STRERROR_SIZE];
      my_error(EE_BADCLOSE, MYF(ME_BELL+ME_WAITTANG), 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);
#if !defined(HAVE_PREAD) && !defined(_WIN32)
    mysql_mutex_destroy(&my_file_info[fd].mutex);
#endif
    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)
{
  DBUG_ENTER("my_register_filename");
  if ((int) fd >= MY_FILE_MIN)
  {
    if ((uint) fd >= my_file_limit)
    {
#if !defined(HAVE_PREAD) 
      my_errno= EMFILE;
#else
      thread_safe_increment(my_file_opened,&THR_LOCK_open);
      DBUG_RETURN(fd);                          /* safeguard */
#endif
    }
    else
    {
      mysql_mutex_lock(&THR_LOCK_open);
      if ((my_file_info[fd].name = (char*) my_strdup(FileName,MyFlags)))
      {
        my_file_opened++;
        my_file_total_opened++;
        my_file_info[fd].type = type_of_file;
#if !defined(HAVE_PREAD) && !defined(_WIN32)
        mysql_mutex_init(key_my_file_info_mutex, &my_file_info[fd].mutex,
                         MY_MUTEX_INIT_FAST);
#endif
        mysql_mutex_unlock(&THR_LOCK_open);
        DBUG_PRINT("exit",("fd: %d",fd));
        DBUG_RETURN(fd);
      }
      mysql_mutex_unlock(&THR_LOCK_open);
      my_errno= ENOMEM;
    }
    (void) my_close(fd, MyFlags);
  }
  else
    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(ME_BELL+ME_WAITTANG), 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)
      {
        fprintf(stderr, EE(EE_FILE_NOT_CLOSED), my_file_info[i].name, i);
        fputc('\n', stderr);
      }
    }
  }
}

#endif