~drizzle-trunk/drizzle/development

/* Copyright (C) 2000 MySQL AB

   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/* Open a temporary file and cache it with io_cache. Delete it on close */

#include "mysys_priv.h"

#include <m_string.h>

#include "my_static.h"

#include "mysys_err.h"

	/*

	  Remove an open tempfile so that it doesn't survive

	  if we crash;	If the operating system doesn't support

	  this, just remember the file name for later removal

	*/

static my_bool cache_remove_open_tmp(IO_CACHE *cache __attribute__((unused)),

				     const char *name)

{

#if O_TEMPORARY == 0

#if !defined(CANT_DELETE_OPEN_FILES)

  /* The following should always succeed */

  (void) my_delete(name,MYF(MY_WME | ME_NOINPUT));

#else

  int length;

  if (!(cache->file_name=

	(char*) my_malloc((length=strlen(name)+1),MYF(MY_WME))))

  {

    my_close(cache->file,MYF(0));

    cache->file = -1;

    errno=my_errno=ENOMEM;

    return 1;

  }

  memcpy(cache->file_name,name,length);

#endif

#endif /* O_TEMPORARY == 0 */

  return 0;

}

	/*

	** Open tempfile cached by IO_CACHE

	** Should be used when no seeks are done (only reinit_io_buff)

	** Return 0 if cache is inited ok

	** The actual file is created when the IO_CACHE buffer gets filled

	** If dir is not given, use TMPDIR.

	*/

my_bool open_cached_file(IO_CACHE *cache, const char* dir, const char *prefix,

                         size_t cache_size, myf cache_myflags)

{

  DBUG_ENTER("open_cached_file");

  cache->dir=	 dir ? my_strdup(dir,MYF(cache_myflags & MY_WME)) : (char*) 0;

  cache->prefix= (prefix ? my_strdup(prefix,MYF(cache_myflags & MY_WME)) :

		 (char*) 0);

  cache->file_name=0;

  cache->buffer=0;				/* Mark that not open */

  if (!init_io_cache(cache,-1,cache_size,WRITE_CACHE,0L,0,

		     MYF(cache_myflags | MY_NABP)))

  {

    DBUG_RETURN(0);

  }

  my_free(cache->dir,	MYF(MY_ALLOW_ZERO_PTR));

  my_free(cache->prefix,MYF(MY_ALLOW_ZERO_PTR));

  DBUG_RETURN(1);

}

	/* Create the temporary file */

my_bool real_open_cached_file(IO_CACHE *cache)

{

  char name_buff[FN_REFLEN];

  int error=1;

  DBUG_ENTER("real_open_cached_file");

  if ((cache->file=create_temp_file(name_buff, cache->dir, cache->prefix,

				    (O_RDWR | O_BINARY | O_TRUNC |

				     O_TEMPORARY | O_SHORT_LIVED),

				    MYF(MY_WME))) >= 0)

  {

    error=0;

    cache_remove_open_tmp(cache, name_buff);

  }

  DBUG_RETURN(error);

}

void close_cached_file(IO_CACHE *cache)

{

  DBUG_ENTER("close_cached_file");

  if (my_b_inited(cache))

  {

    File file=cache->file;

    cache->file= -1;				/* Don't flush data */

    (void) end_io_cache(cache);

    if (file >= 0)

    {

      (void) my_close(file,MYF(0));

#ifdef CANT_DELETE_OPEN_FILES

      if (cache->file_name)

      {

	(void) my_delete(cache->file_name,MYF(MY_WME | ME_NOINPUT));

	my_free(cache->file_name,MYF(0));

      }

#endif

    }

    my_free(cache->dir,MYF(MY_ALLOW_ZERO_PTR));

    my_free(cache->prefix,MYF(MY_ALLOW_ZERO_PTR));

  }

  DBUG_VOID_RETURN;

}