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-rw-r--r--mysql/mysys/my_chsize.c106
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diff --git a/mysql/mysys/my_chsize.c b/mysql/mysys/my_chsize.c
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+/* Copyright (c) 2000, 2015, 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 "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 */