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- /* Copyright (c) 2000, 2021, 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 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 */
-
- #include "mysys_priv.h"
- #include "my_sys.h"
- #include "mysys_err.h"
- #include "m_string.h"
- #include "my_thread_local.h"
-
- /*
- Change size of file.
-
- SYNOPSIS
- my_chsize()
- fd File descriptor
- new_length New file size
- filler If we don't have truncate, fill up all bytes after
- new_length with this character
- MyFlags Flags
-
- DESCRIPTION
- my_chsize() truncates file if shorter else fill with the filler character.
- The function also changes the file pointer. Usually it points to the end
- of the file after execution.
-
- RETURN VALUE
- 0 Ok
- 1 Error
- */
- int my_chsize(File fd, my_off_t newlength, int filler, myf MyFlags)
- {
- my_off_t oldsize;
- uchar buff[IO_SIZE];
- DBUG_ENTER("my_chsize");
- DBUG_PRINT("my",("fd: %d length: %lu MyFlags: %d",fd,(ulong) newlength,
- MyFlags));
-
- if ((oldsize= my_seek(fd, 0L, MY_SEEK_END, MYF(MY_WME+MY_FAE))) == newlength)
- DBUG_RETURN(0);
-
- DBUG_PRINT("info",("old_size: %ld", (ulong) oldsize));
-
- if (oldsize > newlength)
- {
- #ifdef _WIN32
- if (my_win_chsize(fd, newlength))
- {
- set_my_errno(errno);
- goto err;
- }
- DBUG_RETURN(0);
- #elif defined(HAVE_FTRUNCATE)
- if (ftruncate(fd, (off_t) newlength))
- {
- set_my_errno(errno);
- goto err;
- }
- DBUG_RETURN(0);
- #else
- /*
- Fill space between requested length and true length with 'filler'
- We should never come here on any modern machine
- */
- if (my_seek(fd, newlength, MY_SEEK_SET, MYF(MY_WME+MY_FAE))
- == MY_FILEPOS_ERROR)
- {
- goto err;
- }
- swap_variables(my_off_t, newlength, oldsize);
- #endif
- }
-
- /* Full file with 'filler' until it's as big as requested */
- memset(buff, filler, IO_SIZE);
- while (newlength-oldsize > IO_SIZE)
- {
- if (my_write(fd, buff, IO_SIZE, MYF(MY_NABP)))
- goto err;
- oldsize+= IO_SIZE;
- }
- if (my_write(fd,buff,(size_t) (newlength-oldsize), MYF(MY_NABP)))
- goto err;
- DBUG_RETURN(0);
-
- err:
- DBUG_PRINT("error", ("errno: %d", errno));
- if (MyFlags & MY_WME)
- {
- char errbuf[MYSYS_STRERROR_SIZE];
- my_error(EE_CANT_CHSIZE, MYF(0),
- my_errno(), my_strerror(errbuf, sizeof(errbuf), my_errno()));
- }
- DBUG_RETURN(1);
- } /* my_chsize */
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