242 lines
8.6 KiB
C
242 lines
8.6 KiB
C
|
/***
|
||
|
|
*_sftbuf.c - temporary buffering initialization and flushing
|
||
|
|
*
|
||
|
|
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* temporary buffering initialization and flushing. if stdout/err is
|
||
|
|
* unbuffered, buffer it temporarily so that string is sent to kernel as
|
||
|
|
* a batch of chars, not char-at-a-time. if appropriate, make buffering
|
||
|
|
* permanent.
|
||
|
|
*
|
||
|
|
* [NOTE 1: These routines assume that the temporary buffering is only
|
||
|
|
* used for output. In particular, note that _stbuf() sets _IOWRT.]
|
||
|
|
*
|
||
|
|
* [NOTE 2: It is valid for this module to assign a value directly to
|
||
|
|
* _flag instead of simply twiddling bits since we are initializing the
|
||
|
|
* buffer data base.]
|
||
|
|
*
|
||
|
|
*Revision History:
|
||
|
|
* 09-01-83 RN initial version
|
||
|
|
* 06-26-85 TC added code to _stbuf to allow variable buffer lengths
|
||
|
|
* ??-??-?? TC fixed case in _flbuf where flag is off, but a temporary
|
||
|
|
* buffer still needs to be fflushed.
|
||
|
|
* 05-27-87 JCR protect mode does not know about stdprn.
|
||
|
|
* 06-26-87 JCR Conditionalized out code in _ftbuf that caused
|
||
|
|
* redirected stdout to be flushed on every call.
|
||
|
|
* 07-01-87 JCR Put in code to support re-entrant calling from
|
||
|
|
* interrupt level (MSC only).
|
||
|
|
* 08-06-87 JCR Fixed a _ftbuf() problem pertaining to stderr/stdprn
|
||
|
|
* when _bufout is being used by stdout.
|
||
|
|
* 08-07-87 JCR (1) When assigning _bufout to an _iob, we now set the
|
||
|
|
* _IOWRT flag. This fixes a bug involving freopen()
|
||
|
|
* issued against one of the std handles.
|
||
|
|
* (2) Removed some annoying commented out code.
|
||
|
|
* 08-13-87 JCR _ftbuf() does NOT clear _IOWRT now. Fixes a bug where
|
||
|
|
* _getstream() would reassign stdout because none of the
|
||
|
|
* flags were set.
|
||
|
|
* 09-28-87 JCR Corrected _iob2 indexing (now uses _iob_index() macro).
|
||
|
|
* 11-05-87 JCR Re-written for multi-thread support and simplicity
|
||
|
|
* 01-11-88 JCR Merged mthread version into normal version
|
||
|
|
* 01-13-88 SKS Changed bogus "_fileno_lk" to "fileno"
|
||
|
|
* 06-06-88 JCR Optimized _iob2 references
|
||
|
|
* 06-10-88 JCR Use near pointer to reference _iob[] entries
|
||
|
|
* 06-27-88 JCR Added stdprn temporary buffering support (DOS only),
|
||
|
|
* and made buffer allocation dynamic; also added _IOFLRTN
|
||
|
|
* (flush stream on per routine basis).
|
||
|
|
* 08-25-88 GJF Modified to also work for the 386 (small model only).
|
||
|
|
* 06-20-89 PHG Changed return value to void
|
||
|
|
* 08-28-89 JCR Removed _NEAR_ for 386
|
||
|
|
* 02-15-90 GJF _iob[], _iob2[] merge. Also, fixed copyright and
|
||
|
|
* indents.
|
||
|
|
* 03-16-90 GJF Made calling type _CALLTYPE1, added #include
|
||
|
|
* <cruntime.h> and removed #include <register.h>. Also,
|
||
|
|
* removed some leftover 16-bit DOS support.
|
||
|
|
* 03-27-90 GJF Added #include <io.h>.
|
||
|
|
* 05-29-90 SBM Use _flush, not [_]fflush[_lk]
|
||
|
|
* 07-23-90 SBM Replaced <assertm.h> by <assert.h>
|
||
|
|
* 10-03-90 GJF New-style function declarator.
|
||
|
|
* 01-22-91 GJF ANSI naming.
|
||
|
|
* 03-27-92 DJM POSIX support.
|
||
|
|
* 08-26-92 GJF Include unistd.h for POSIX build.
|
||
|
|
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
|
||
|
|
* 05-11-93 GJF Replaced BUFSIZ with _INTERNAL_BUFSIZ.
|
||
|
|
* 04-05-94 GJF #ifdef-ed out _cflush reference for msvcrt*.dll, it
|
||
|
|
* is unnecessary. Also, replaced MTHREAD with _MT.
|
||
|
|
* 01-10-95 CFW Debug CRT allocs.
|
||
|
|
* 02-06-94 CFW assert -> _ASSERTE.
|
||
|
|
* 02-17-95 GJF Merged in Mac version.
|
||
|
|
* 02-07-97 GJF Changed _stbuf() to use _charbuf when malloc fails.
|
||
|
|
* Also, detab-ed.
|
||
|
|
* 05-17-99 PML Remove all Macintosh support.
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
#include <cruntime.h>
|
||
|
|
#ifdef _POSIX_
|
||
|
|
#include <unistd.h>
|
||
|
|
#endif
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <file2.h>
|
||
|
|
#include <io.h>
|
||
|
|
#include <internal.h>
|
||
|
|
#include <malloc.h>
|
||
|
|
#ifdef _MT
|
||
|
|
#include <mtdll.h>
|
||
|
|
#endif
|
||
|
|
#include <dbgint.h>
|
||
|
|
|
||
|
|
/* Buffer pointers for stdout and stderr */
|
||
|
|
void *_stdbuf[2] = { NULL, NULL};
|
||
|
|
|
||
|
|
/***
|
||
|
|
*int _stbuf(stream) - set temp buffer on stdout, stdprn, stderr
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* if stdout/stderr is still unbuffered, buffer it.
|
||
|
|
* this function works intimately with _ftbuf, and accompanies it in
|
||
|
|
* bracketing normally unbuffered output. these functions intended for
|
||
|
|
* library use only.
|
||
|
|
*
|
||
|
|
* Multi-thread: It is assumed that the caller has already aquired the
|
||
|
|
* stream lock.
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* FILE *stream - stream to temp buffer
|
||
|
|
*
|
||
|
|
*Exit:
|
||
|
|
* returns 1 if buffer initialized, 0 if not
|
||
|
|
* sets fields in stdout or stderr to indicate buffering
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
int __cdecl _stbuf (
|
||
|
|
FILE *str
|
||
|
|
)
|
||
|
|
{
|
||
|
|
REG1 FILE *stream;
|
||
|
|
int index;
|
||
|
|
|
||
|
|
_ASSERTE(str != NULL);
|
||
|
|
|
||
|
|
/* Init near stream pointer */
|
||
|
|
stream = str;
|
||
|
|
|
||
|
|
/* do nothing if not a tty device */
|
||
|
|
#ifdef _POSIX_
|
||
|
|
if (!isatty(fileno(stream)))
|
||
|
|
#else
|
||
|
|
if (!_isatty(_fileno(stream)))
|
||
|
|
#endif
|
||
|
|
return(0);
|
||
|
|
|
||
|
|
/* Make sure stream is stdout/stderr and init _stdbuf index */
|
||
|
|
if (stream == stdout)
|
||
|
|
index = 0;
|
||
|
|
else if (stream == stderr)
|
||
|
|
index = 1;
|
||
|
|
else
|
||
|
|
return(0);
|
||
|
|
|
||
|
|
#ifndef CRTDLL
|
||
|
|
/* force library pre-termination procedure */
|
||
|
|
_cflush++;
|
||
|
|
#endif /* CRTDLL */
|
||
|
|
|
||
|
|
/* Make sure the stream is not already buffered. */
|
||
|
|
if (anybuf(stream))
|
||
|
|
return(0);
|
||
|
|
|
||
|
|
/* Allocate a buffer for this stream if we haven't done so yet. */
|
||
|
|
if ( (_stdbuf[index] == NULL) &&
|
||
|
|
((_stdbuf[index]=_malloc_crt(_INTERNAL_BUFSIZ)) == NULL) ) {
|
||
|
|
/* Cannot allocate buffer. Use _charbuf this time */
|
||
|
|
stream->_ptr = stream->_base = (void *)&(stream->_charbuf);
|
||
|
|
stream->_cnt = stream->_bufsiz = 2;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
/* Set up the buffer */
|
||
|
|
stream->_ptr = stream->_base = _stdbuf[index];
|
||
|
|
stream->_cnt = stream->_bufsiz = _INTERNAL_BUFSIZ;
|
||
|
|
}
|
||
|
|
|
||
|
|
stream->_flag |= (_IOWRT | _IOYOURBUF | _IOFLRTN);
|
||
|
|
|
||
|
|
return(1);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/***
|
||
|
|
*void _ftbuf(flag, stream) - take temp buffering off a stream
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* If stdout/stderr is being buffered and it is a device, _flush and
|
||
|
|
* dismantle the buffer. if it's not a device, leave the buffering on.
|
||
|
|
* This function works intimately with _stbuf, and accompanies it in
|
||
|
|
* bracketing normally unbuffered output. these functions intended for
|
||
|
|
* library use only
|
||
|
|
*
|
||
|
|
* Multi-thread: It is assumed that the caller has already aquired the
|
||
|
|
* stream lock.
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* int flag - a flag to tell whether to dismantle temp buffering on a
|
||
|
|
* stream
|
||
|
|
* FILE *stream - the stream
|
||
|
|
*
|
||
|
|
*Exit:
|
||
|
|
* no return value
|
||
|
|
* sets fields in stdout/stderr
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
void __cdecl _ftbuf (
|
||
|
|
int flag,
|
||
|
|
FILE *str
|
||
|
|
)
|
||
|
|
{
|
||
|
|
REG1 FILE *stream;
|
||
|
|
|
||
|
|
_ASSERTE(flag == 0 || flag == 1);
|
||
|
|
|
||
|
|
/* Init near stream pointers */
|
||
|
|
stream = str;
|
||
|
|
|
||
|
|
if (flag) {
|
||
|
|
|
||
|
|
if (stream->_flag & _IOFLRTN) {
|
||
|
|
|
||
|
|
/* Flush the stream and tear down temp buffering. */
|
||
|
|
_flush(stream);
|
||
|
|
stream->_flag &= ~(_IOYOURBUF | _IOFLRTN);
|
||
|
|
stream->_bufsiz = 0;
|
||
|
|
stream->_base = stream->_ptr = NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Note: If we expand the functionality of the _IOFLRTN bit to
|
||
|
|
include other streams, we may want to clear that bit here under
|
||
|
|
an 'else' clause (i.e., clear bit in the case that we leave the
|
||
|
|
buffer permanently assigned. Given our current use of the bit,
|
||
|
|
the extra code is not needed. */
|
||
|
|
|
||
|
|
} /* end flag = 1 */
|
||
|
|
|
||
|
|
#ifndef _MT
|
||
|
|
/* NOTE: Currently, writing to the same string at interrupt level does not
|
||
|
|
work in multi-thread programs. */
|
||
|
|
|
||
|
|
/* The following code is needed if an interrupt occurs between calls
|
||
|
|
to _stbuf/_ftbuf and the interrupt handler also calls _stbuf/_ftbuf. */
|
||
|
|
|
||
|
|
else
|
||
|
|
if (stream->_flag & _IOFLRTN)
|
||
|
|
_flush(stream);
|
||
|
|
|
||
|
|
#endif /* _MT */
|
||
|
|
|
||
|
|
}
|