mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-23 17:53:37 +08:00
101 lines
3.1 KiB
C
101 lines
3.1 KiB
C
/* Copyright (C) 1993-2016 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>.
|
|
|
|
As a special exception, if you link the code in this file with
|
|
files compiled with a GNU compiler to produce an executable,
|
|
that does not cause the resulting executable to be covered by
|
|
the GNU Lesser General Public License. This exception does not
|
|
however invalidate any other reasons why the executable file
|
|
might be covered by the GNU Lesser General Public License.
|
|
This exception applies to code released by its copyright holders
|
|
in files containing the exception. */
|
|
|
|
#include "libioP.h"
|
|
|
|
#define _IOFBF 0 /* Fully buffered. */
|
|
#define _IOLBF 1 /* Line buffered. */
|
|
#define _IONBF 2 /* No buffering. */
|
|
|
|
int
|
|
_IO_setvbuf (_IO_FILE *fp, char *buf, int mode, _IO_size_t size)
|
|
{
|
|
int result;
|
|
CHECK_FILE (fp, EOF);
|
|
_IO_acquire_lock (fp);
|
|
switch (mode)
|
|
{
|
|
case _IOFBF:
|
|
fp->_IO_file_flags &= ~(_IO_LINE_BUF|_IO_UNBUFFERED);
|
|
if (buf == NULL)
|
|
{
|
|
if (fp->_IO_buf_base == NULL)
|
|
{
|
|
/* There is no flag to distinguish between "fully buffered
|
|
mode has been explicitly set" as opposed to "line
|
|
buffering has not been explicitly set". In both
|
|
cases, _IO_LINE_BUF is off. If this is a tty, and
|
|
_IO_filedoalloc later gets called, it cannot know if
|
|
it should set the _IO_LINE_BUF flag (because that is
|
|
the default), or not (because we have explicitly asked
|
|
for fully buffered mode). So we make sure a buffer
|
|
gets allocated now, and explicitly turn off line
|
|
buffering.
|
|
|
|
A possibly cleaner alternative would be to add an
|
|
extra flag, but then flags are a finite resource. */
|
|
if (_IO_DOALLOCATE (fp) < 0)
|
|
{
|
|
result = EOF;
|
|
goto unlock_return;
|
|
}
|
|
fp->_IO_file_flags &= ~_IO_LINE_BUF;
|
|
}
|
|
result = 0;
|
|
goto unlock_return;
|
|
}
|
|
break;
|
|
case _IOLBF:
|
|
fp->_IO_file_flags &= ~_IO_UNBUFFERED;
|
|
fp->_IO_file_flags |= _IO_LINE_BUF;
|
|
if (buf == NULL)
|
|
{
|
|
result = 0;
|
|
goto unlock_return;
|
|
}
|
|
break;
|
|
case _IONBF:
|
|
fp->_IO_file_flags &= ~_IO_LINE_BUF;
|
|
fp->_IO_file_flags |= _IO_UNBUFFERED;
|
|
buf = NULL;
|
|
size = 0;
|
|
break;
|
|
default:
|
|
result = EOF;
|
|
goto unlock_return;
|
|
}
|
|
result = _IO_SETBUF (fp, buf, size) == NULL ? EOF : 0;
|
|
|
|
unlock_return:
|
|
_IO_release_lock (fp);
|
|
return result;
|
|
}
|
|
libc_hidden_def (_IO_setvbuf)
|
|
|
|
#ifdef weak_alias
|
|
weak_alias (_IO_setvbuf, setvbuf)
|
|
#endif
|