windows-nt/Source/XPSP1/NT/base/crts/crtw32/stdio/_flsbuf.c

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/***
*_flsbuf.c - flush buffer and output character.
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines _flsbuf() - flush a file buffer and output a character.
* defines _flswbuf() - flush a file buffer and output a wide character.
* If no buffer, make one.
*
*Revision History:
* 09-01-83 RN initial version
* 06-26-85 TC added code to handle variable length buffers
* 06-08-87 JCR When buffer is allocated or when first write to buffer
* occurs, if stream is in append mode, then position file
* pointer to end.
* 07-20-87 SKS Change first parameter "ch" from (char) to (int)
* 09-28-87 JCR Corrected _iob2 indexing (now uses _iob_index() macro).
* 11-05-87 JCR Re-wrote for simplicity and for new stderr/stdout
* handling
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 01-11-88 JCR Merged mthread version into normal code
* 01-13-88 SKS Changed bogus "_fileno_lk" to "fileno"
* 06-06-88 JCR Optimized _iob2 references
* 06-13-88 JCR Use near pointer to reference _iob[] entries
* 06-28-88 JCR Support for dynamic buffer allocation for stdout/stderr
* 07-28-88 GJF Set stream->_cnt to 0 if _IOREAD is set.
* 08-25-88 GJF Added checked that OS2 is defined whenever M_I386 is.
* 06-20-89 PHG Removed FP_OFF macro call.
* 08-28-89 JCR Removed _NEAR_ for 386
* 02-15-90 GJF _iob[], _iob2[] merge. Also, fixed copyright and
* indents.
* 03-16-90 GJF Replaced cdecl _LOAD_DS with _CALLTYPE1, added #include
* <cruntime.h> and removed #include <register.h>. Also,
* removed some leftover 16-bit support.
* 03-27-90 GJF Added #include <io.h>.
* 07-23-90 SBM Replaced <assertm.h> by <assert.h>
* 08-07-90 SBM Restored descriptive text in assertion
* 08-14-90 SBM Compiles cleanly with -W3
* 10-03-90 GJF New-style function declarator.
* 01-22-91 GJF ANSI naming.
* 03-25-91 DJM POSIX support
* 08-26-92 GJF Include unistd.h for POSIX build.
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* 04-26-93 CFW Wide char enable.
* 05-06-93 CFW Optimize wide char conversion.
* 11-05-93 GJF Merged with NT SDK version (picked up _NTSUBSET_
* stuff).
* 10-17-94 BWT Move wchar.h to non-POSIX build (ino_t definitions conflict)
* 02-06-94 CFW assert -> _ASSERTE.
* 02-16-95 GJF Appended Mac version of source file (somewhat cleaned
* up), with appropriate #ifdef-s.
* 06-12-95 GJF Replaced _osfile[] with _osfile() (macro referencing
* field in ioinfo struct).
* 07-25-95 GJF Replaced _osfile()with _osfile_safe().
* 12-07-95 SKS Fix misspelling of _NTSUBSET_ (final _ was missing)
* 02-27-98 RKP Added 64 bit support.
* 01-04-99 GJF Changes for 64-bit size_t.
* 05-17-99 PML Remove all Macintosh support.
*
*******************************************************************************/
#include <cruntime.h>
#include <stdio.h>
#include <file2.h>
#include <io.h>
#include <dbgint.h>
#include <malloc.h>
#ifdef _POSIX_
#include <unistd.h>
#include <errno.h>
#else
#include <msdos.h>
#include <wchar.h>
#endif
#include <internal.h>
#ifdef _MT
#include <mtdll.h>
#endif
#include <tchar.h>
#ifndef _UNICODE
/***
*int _flsbuf(ch, stream) - flush buffer and output character.
*
*Purpose:
* flush a buffer if this stream has one. if not, try to get one. put the
* next output char (ch) into the buffer (or output it immediately if this
* stream can't have a buffer). called only from putc. intended for use
* only within library.
*
* [NOTE: Multi-thread - It is assumed that the caller has aquired
* the stream lock.]
*
*Entry:
* FILE *stream - stream to flish and write on
* int ch - character to output.
*
*Exit:
* returns -1 if FILE is actually a string, or if can't write ch to
* unbuffered file, or if we flush a buffer but the number of chars
* written doesn't agree with buffer size. Otherwise returns ch.
* all fields in FILE struct can be affected except _file.
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _flsbuf (
int ch,
FILE *str
)
#else /* _UNICODE */
/***
*int _flswbuf(ch, stream) - flush buffer and output wide character.
*
*Purpose:
* flush a buffer if this stream has one. if not, try to get one. put the
* next output wide char (ch) into the buffer (or output it immediately if this
* stream can't have a buffer). called only from putwc. intended for use
* only within library.
*
* [NOTE: Multi-thread - It is assumed that the caller has aquired
* the stream lock.]
*
*Entry:
* FILE *stream - stream to flish and write on
* int ch - wide character to output.
*
*Exit:
* returns -1 if FILE is actually a string, or if can't write ch to
* unbuffered file, or if we flush a buffer but the number of wide chars
* written doesn't agree with buffer size. Otherwise returns ch.
* all fields in FILE struct can be affected except _file.
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _flswbuf (
int ch,
FILE *str
)
#endif /* _UNICODE */
{
#ifdef _NTSUBSET_
str->_flag |= _IOERR;
return(_TEOF);
#else /* ndef _NTSUBSET_ */
REG1 FILE *stream;
REG2 int charcount;
REG3 int written;
int fh;
_ASSERTE(str != NULL);
/* Init file handle and pointers */
stream = str;
#ifdef _POSIX_
fh = fileno(stream);
#else
fh = _fileno(stream);
#endif
if (!(stream->_flag & (_IOWRT|_IORW)) || (stream->_flag & _IOSTRG)) {
#ifdef _POSIX_
errno = EBADF;
#endif
stream->_flag |= _IOERR;
return(_TEOF);
}
/* Check that _IOREAD is not set or, if it is, then so is _IOEOF. Note
that _IOREAD and IOEOF both being set implies switching from read to
write at end-of-file, which is allowed by ANSI. Note that resetting
the _cnt and _ptr fields amounts to doing an fflush() on the stream
in this case. Note also that the _cnt field has to be reset to 0 for
the error path as well (i.e., _IOREAD set but _IOEOF not set) as
well as the non-error path. */
if (stream->_flag & _IOREAD) {
stream->_cnt = 0;
if (stream->_flag & _IOEOF) {
stream->_ptr = stream->_base;
stream->_flag &= ~_IOREAD;
}
else {
stream->_flag |= _IOERR;
return(_TEOF);
}
}
stream->_flag |= _IOWRT;
stream->_flag &= ~_IOEOF;
written = charcount = stream->_cnt = 0;
/* Get a buffer for this stream, if necessary. */
if (!anybuf(stream)) {
/* Do NOT get a buffer if (1) stream is stdout/stderr, and
(2) stream is NOT a tty.
[If stdout/stderr is a tty, we do NOT set up single char
buffering. This is so that later temporary buffering will
not be thwarted by the _IONBF bit being set (see
_stbuf/_ftbuf usage).]
*/
if (!( ((stream==stdout) || (stream==stderr))
#ifdef _POSIX_
&& (isatty(fh)) ))
#else
&& (_isatty(fh)) ))
#endif
_getbuf(stream);
} /* end !anybuf() */
/* If big buffer is assigned to stream... */
if (bigbuf(stream)) {
_ASSERTE(("inconsistent IOB fields", stream->_ptr - stream->_base >= 0));
charcount = (int)(stream->_ptr - stream->_base);
stream->_ptr = stream->_base + sizeof(TCHAR);
stream->_cnt = stream->_bufsiz - (int)sizeof(TCHAR);
if (charcount > 0)
#ifdef _POSIX_
written = write(fh, stream->_base, charcount);
#else
written = _write(fh, stream->_base, charcount);
#endif
else
#ifdef _POSIX_
if (stream->_flag & _IOAPPEND)
lseek(fh,0l,SEEK_END);
#else
if (_osfile_safe(fh) & FAPPEND)
_lseek(fh,0L,SEEK_END);
#endif
#ifndef _UNICODE
*stream->_base = (char)ch;
#else /* _UNICODE */
*(wchar_t *)(stream->_base) = (wchar_t)(ch & 0xffff);
#endif /* _UNICODE */
}
/* Perform single character output (either _IONBF or no buffering) */
else {
charcount = sizeof(TCHAR);
#ifndef _UNICODE
#ifdef _POSIX_
written = write(fh, &ch, charcount);
#else
written = _write(fh, &ch, charcount);
#endif
#else /* _UNICODE */
{
char mbc[4];
*(wchar_t *)mbc = (wchar_t)(ch & 0xffff);
#ifdef _POSIX_
written = write(fh, mbc, charcount);
#else
written = _write(fh, mbc, charcount);
#endif
}
#endif /* _UNICODE */
}
/* See if the _write() was successful. */
if (written != charcount) {
stream->_flag |= _IOERR;
return(_TEOF);
}
#ifndef _UNICODE
return(ch & 0xff);
#else /* _UNICODE */
return(ch & 0xffff);
#endif /* _UNICODE */
#endif /* _NTSUBSET_ */
}