newlib-cygwin/newlib/libc/stdio/setvbuf.c

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/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/*
FUNCTION
<<setvbuf>>---specify file or stream buffering
INDEX
setvbuf
ANSI_SYNOPSIS
#include <stdio.h>
int setvbuf(FILE *<[fp]>, char *<[buf]>,
int <[mode]>, size_t <[size]>);
TRAD_SYNOPSIS
#include <stdio.h>
int setvbuf(<[fp]>, <[buf]>, <[mode]>, <[size]>)
FILE *<[fp]>;
char *<[buf]>;
int <[mode]>;
size_t <[size]>;
DESCRIPTION
Use <<setvbuf>> to specify what kind of buffering you want for the
file or stream identified by <[fp]>, by using one of the following
values (from <<stdio.h>>) as the <[mode]> argument:
o+
o _IONBF
Do not use a buffer: send output directly to the host system for the
file or stream identified by <[fp]>.
o _IOFBF
Use full output buffering: output will be passed on to the host system
only when the buffer is full, or when an input operation intervenes.
o _IOLBF
Use line buffering: pass on output to the host system at every
newline, as well as when the buffer is full, or when an input
operation intervenes.
o-
Use the <[size]> argument to specify how large a buffer you wish. You
can supply the buffer itself, if you wish, by passing a pointer to a
suitable area of memory as <[buf]>. Otherwise, you may pass <<NULL>>
as the <[buf]> argument, and <<setvbuf>> will allocate the buffer.
WARNINGS
You may only use <<setvbuf>> before performing any file operation other
than opening the file.
If you supply a non-null <[buf]>, you must ensure that the associated
storage continues to be available until you close the stream
identified by <[fp]>.
RETURNS
A <<0>> result indicates success, <<EOF>> failure (invalid <[mode]> or
<[size]> can cause failure).
PORTABILITY
Both ANSI C and the System V Interface Definition (Issue 2) require
<<setvbuf>>. However, they differ on the meaning of a <<NULL>> buffer
pointer: the SVID issue 2 specification says that a <<NULL>> buffer
pointer requests unbuffered output. For maximum portability, avoid
<<NULL>> buffer pointers.
Both specifications describe the result on failure only as a
nonzero value.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#include <_ansi.h>
#include <stdio.h>
#include <stdlib.h>
#include "local.h"
/*
* Set one of the three kinds of buffering, optionally including a buffer.
*/
int
2004-04-23 Artem B. Bityuckiy <abitytsky@softminecorp.com> * libc/stdio/asprintf.c libc/stdio/clearerr.c, libc/stdio/fclose.c libc/stdio/fcloseall.c libc/stdio/fdopen.c, libc/stdio/feof.c libc/stdio/ferror.c libc/stdio/fflush.c, libc/stdio/fgetc.c libc/stdio/fgetpos.c libc/stdio/fgets.c, libc/stdio/fileno.c libc/stdio/findfp.c libc/stdio/fiprintf.c, libc/stdio/flags.c libc/stdio/fopen.c libc/stdio/fprintf.c, libc/stdio/fputc.c libc/stdio/fputs.c libc/stdio/fread.c, libc/stdio/freopen.c libc/stdio/fscanf.c libc/stdio/fseek.c, libc/stdio/fseeko.c libc/stdio/fsetpos.c libc/stdio/ftell.c, libc/stdio/ftello.c libc/stdio/fvwrite.c libc/stdio/fwalk.c, libc/stdio/fwrite.c libc/stdio/getc.c libc/stdio/getc_u.c, libc/stdio/getchar.c libc/stdio/getchar_u.c, libc/stdio/getdelim.c libc/stdio/getline.c libc/stdio/gets.c, libc/stdio/getw.c libc/stdio/iprintf.c libc/stdio/local.h, libc/stdio/makebuf.c libc/stdio/mktemp.c libc/stdio/perror.c, libc/stdio/printf.c libc/stdio/putc.c libc/stdio/putc_u.c, libc/stdio/putchar.c libc/stdio/putchar_u.c libc/stdio/puts.c, libc/stdio/putw.c libc/stdio/refill.c libc/stdio/remove.c, libc/stdio/rename.c libc/stdio/rewind.c libc/stdio/rget.c, libc/stdio/scanf.c libc/stdio/setbuf.c libc/stdio/setbuffer.c, libc/stdio/setlinebuf.c libc/stdio/setvbuf.c, libc/stdio/siprintf.c libc/stdio/snprintf.c, libc/stdio/sprintf.c libc/stdio/sscanf.c libc/stdio/stdio.c, libc/stdio/tmpfile.c libc/stdio/tmpnam.c libc/stdio/ungetc.c, libc/stdio/vasprintf.c libc/stdio/vfieeefp.h, libc/stdio/vfprintf.c libc/stdio/vfscanf.c, libc/stdio/vprintf.c libc/stdio/vscanf.c, libc/stdio/vsnprintf.c libc/stdio/vsprintf.c, libc/stdio/vsscanf.c libc/stdio/wbuf.c, libc/stdio/wsetup.c: Perform minor formatting changes. Move copyright notices to top of file, ensure that <_ansi.h> is included, be consistent with open parentheses, use _DEFUN macro, include "local.h" where needed, and remove various compiler warnings.
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_DEFUN(setvbuf, (fp, buf, mode, size),
register FILE * fp _AND
char *buf _AND
register int mode _AND
register size_t size)
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{
int ret = 0;
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CHECK_INIT (_REENT, fp);
_newlib_flockfile_start (fp);
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/*
* Verify arguments. The `int' limit on `size' is due to this
* particular implementation.
*/
if ((mode != _IOFBF && mode != _IOLBF && mode != _IONBF) || (int)(_POINTER_INT) size < 0)
{
_newlib_flockfile_exit (fp);
return (EOF);
}
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/*
* Write current buffer, if any; drop read count, if any.
* Make sure putc() will not think fp is line buffered.
* Free old buffer if it was from malloc(). Clear line and
* non buffer flags, and clear malloc flag.
*/
_fflush_r (_REENT, fp);
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fp->_r = 0;
fp->_lbfsize = 0;
if (fp->_flags & __SMBF)
2004-04-23 Artem B. Bityuckiy <abitytsky@softminecorp.com> * libc/stdio/asprintf.c libc/stdio/clearerr.c, libc/stdio/fclose.c libc/stdio/fcloseall.c libc/stdio/fdopen.c, libc/stdio/feof.c libc/stdio/ferror.c libc/stdio/fflush.c, libc/stdio/fgetc.c libc/stdio/fgetpos.c libc/stdio/fgets.c, libc/stdio/fileno.c libc/stdio/findfp.c libc/stdio/fiprintf.c, libc/stdio/flags.c libc/stdio/fopen.c libc/stdio/fprintf.c, libc/stdio/fputc.c libc/stdio/fputs.c libc/stdio/fread.c, libc/stdio/freopen.c libc/stdio/fscanf.c libc/stdio/fseek.c, libc/stdio/fseeko.c libc/stdio/fsetpos.c libc/stdio/ftell.c, libc/stdio/ftello.c libc/stdio/fvwrite.c libc/stdio/fwalk.c, libc/stdio/fwrite.c libc/stdio/getc.c libc/stdio/getc_u.c, libc/stdio/getchar.c libc/stdio/getchar_u.c, libc/stdio/getdelim.c libc/stdio/getline.c libc/stdio/gets.c, libc/stdio/getw.c libc/stdio/iprintf.c libc/stdio/local.h, libc/stdio/makebuf.c libc/stdio/mktemp.c libc/stdio/perror.c, libc/stdio/printf.c libc/stdio/putc.c libc/stdio/putc_u.c, libc/stdio/putchar.c libc/stdio/putchar_u.c libc/stdio/puts.c, libc/stdio/putw.c libc/stdio/refill.c libc/stdio/remove.c, libc/stdio/rename.c libc/stdio/rewind.c libc/stdio/rget.c, libc/stdio/scanf.c libc/stdio/setbuf.c libc/stdio/setbuffer.c, libc/stdio/setlinebuf.c libc/stdio/setvbuf.c, libc/stdio/siprintf.c libc/stdio/snprintf.c, libc/stdio/sprintf.c libc/stdio/sscanf.c libc/stdio/stdio.c, libc/stdio/tmpfile.c libc/stdio/tmpnam.c libc/stdio/ungetc.c, libc/stdio/vasprintf.c libc/stdio/vfieeefp.h, libc/stdio/vfprintf.c libc/stdio/vfscanf.c, libc/stdio/vprintf.c libc/stdio/vscanf.c, libc/stdio/vsnprintf.c libc/stdio/vsprintf.c, libc/stdio/vsscanf.c libc/stdio/wbuf.c, libc/stdio/wsetup.c: Perform minor formatting changes. Move copyright notices to top of file, ensure that <_ansi.h> is included, be consistent with open parentheses, use _DEFUN macro, include "local.h" where needed, and remove various compiler warnings.
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_free_r (_REENT, (_PTR) fp->_bf._base);
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fp->_flags &= ~(__SLBF | __SNBF | __SMBF);
if (mode == _IONBF)
goto nbf;
/*
* Allocate buffer if needed. */
if (buf == NULL)
{
/* we need this here because malloc() may return a pointer
even if size == 0 */
if (!size) size = BUFSIZ;
if ((buf = malloc (size)) == NULL)
{
ret = EOF;
/* Try another size... */
buf = malloc (BUFSIZ);
size = BUFSIZ;
}
if (buf == NULL)
{
/* Can't allocate it, let's try another approach */
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nbf:
fp->_flags |= __SNBF;
fp->_w = 0;
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
_newlib_flockfile_exit (fp);
return (ret);
}
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fp->_flags |= __SMBF;
}
/*
* Now put back whichever flag is needed, and fix _lbfsize
* if line buffered. Ensure output flush on exit if the
* stream will be buffered at all.
* If buf is NULL then make _lbfsize 0 to force the buffer
* to be flushed and hence malloced on first use
*/
switch (mode)
{
case _IOLBF:
fp->_flags |= __SLBF;
fp->_lbfsize = buf ? -size : 0;
/* FALLTHROUGH */
case _IOFBF:
/* no flag */
2003-08-22 Jeff Johnston <jjohnstn@redhat.com> * libc/include/sys/reent.h: Add _GLOBAL_REENT macro. * libc/stdio: Globally remove/replace all references to fp->_data. Replace with _REENT or _GLOBAL_REENT where appropriate. * libc/stdio/asprintf.c: Ditto. * libc/stdio/fclose.c: Ditto. * libc/stdio/fvwrite.c: Ditto. * libc/stdio/makebuf.c: Ditto. * libc/stdio/refill.c: Ditto. * libc/stdio/local.h: Ditto. * libc/stdio/setvbuf.c: Ditto. * libc/stdio/sscanf.c: Ditto. * libc/stdio/stdio.c: Ditto. * libc/stdio/ungetc.c: Ditto. * libc/stdio/vfscanf.c: Ditto. * libc/stdio/vsscanf.c: Ditto. * libc/stdio/fopen.c: Ditto. Also use _fseek_r in _fopen_r. * libc/stdio/vasprintf.c: Ditto. Also call _vfprintf_r directly. * libc/stdio/vsnprintf.c: Ditto. * libc/stdio/vsprintf.c: Ditto. * libc/stdio/fcloseall.c(fcloseall): Use _GLOBAL_REENT macro instead of _REENT to walk file list. * libc/stdio/fflush.c: Ditto. * libc/stdio/fgetpos.c: Add reentrant version and have regular version call reentrant version with _REENT argument. * libc/stdio/fsetpos.c: Ditto. * libc/stdio/fseek.c: Ditto. * libc/stdio/fseeko.c: Ditto. * libc/stdio/ftell.c: Ditto. * libc/stdio/ftello.c: Ditto. * libc/stdio/freopen.c: Ditto. * libc/stdio/findfp.c: Use _GLOBAL_REENT pointer when adding new files to chain. Also use _GLOBAL_REENT pointer for cleaning up. * libc/stdio/fiprintf.c: Reformatted to minimize duplicate code. * libc/stdio/siprintf.c: Ditto. * libc/stdio/iprintf.c: Ditto. * libc/stdio/fprintf.c: Ditto. * libc/stdio/printf.c: Ditto. * libc/stdio/snprintf.c: Call _vfprintf_r directly. * libc/stdio/sprintf.c: Ditto. * libc/stdio/vprintf.c: Ditto. Also add _REENT_ONLY check. * libc/stdio/rewind.c: Call _fseek_r directly. * libc/stdio/tmpfile.c: Call _fopen_r and _remove_r directly. * libc/stdio/vfprintf.c (_VFPRINTF_R): Change _r routines to use data pointer. (get_arg): Add extra struct _reent pointer argument. * libc/stdio64/fgetpos64.c: Add _r versions, remove any reference to fp->_data. * libc/stdio64/fopen64.c: Ditto. * libc/stdio64/freopen64.c: Ditto. * libc/stdio64/fsetpos64.c: Ditto. * libc/stdio64/ftello64.c: Ditto. * libc/stdio64/local64.h: Ditto. * libc/stdio64/stdio64.c: Ditto. * libc/stdio64/fseeko64.c: Ditto plus use _fstat_r instead of _fstat64_r for the meantime.
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_REENT->__cleanup = _cleanup_r;
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fp->_bf._base = fp->_p = (unsigned char *) buf;
fp->_bf._size = size;
break;
}
/*
* Patch up write count if necessary.
*/
if (fp->_flags & __SWR)
fp->_w = fp->_flags & (__SLBF | __SNBF) ? 0 : size;
_newlib_flockfile_end (fp);
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return 0;
}