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/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA */
#include "mysys_priv.h"
#include "mysys_err.h"
#include "m_string.h"
/* Change size of file. Truncate file if shorter, */
/* else expand with zero. */
int my_chsize(File fd, my_off_t newlength, myf MyFlags)
{
DBUG_ENTER("my_chsize");
DBUG_PRINT("my",("fd: %d length: %lu MyFlags: %d",fd,(ulong) newlength,
MyFlags));
#ifdef HAVE_CHSIZE
if (chsize(fd,(off_t) newlength))
{
DBUG_PRINT("error",("errno: %d",errno));
my_errno=errno;
if (MyFlags & MY_WME)
my_error(EE_CANT_CHSIZE,MYF(ME_BELL+ME_WAITTANG),errno);
DBUG_RETURN(1);
}
DBUG_RETURN(0);
#else
/* if file is shorter, expand with null, else fill unused part with null */
{
my_off_t oldsize;
char buff[IO_SIZE];
bzero(buff,IO_SIZE);
oldsize = my_seek(fd, 0L, MY_SEEK_END, MYF(MY_WME+MY_FAE));
#ifdef HAVE_FTRUNCATE
if (oldsize > newlength)
{
if (ftruncate(fd, (off_t) newlength))
{
my_errno=errno;
DBUG_PRINT("error",("errno: %d",errno));
if (MyFlags & MY_WME)
my_error(EE_CANT_CHSIZE, MYF(ME_BELL+ME_WAITTANG), errno);
DBUG_RETURN(1);
}
DBUG_RETURN(0);
}
#else
if (oldsize > newlength)
{ /* Fill diff with null */
VOID(my_seek(fd, newlength, MY_SEEK_SET, MYF(MY_WME+MY_FAE)));
swap(long, newlength, oldsize);
}
#endif
while (newlength-oldsize > IO_SIZE)
{
if (my_write(fd,(byte*) buff,IO_SIZE,MYF(MY_NABP)))
goto err;
oldsize+= IO_SIZE;
}
if (my_write(fd,(byte*) buff,(uint) (newlength-oldsize),MYF(MY_NABP)))
goto err;
DBUG_RETURN(0);
err:
if (MyFlags & MY_WME)
my_error(EE_CANT_CHSIZE,MYF(ME_BELL+ME_WAITTANG),my_errno);
DBUG_PRINT("error",("errno: %d",my_errno));
DBUG_RETURN(1);
}
#endif
} /* my_chsize */
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