NT4/private/crt32/lowio/setmode.c
2020-09-30 17:12:29 +02:00

156 lines
3.2 KiB
C

/***
*setmode.c - set file translation mode
*
* Copyright (c) 1985-1992, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defined _setmode() - set file translation mode of a file
*
*Revision History:
* 08-16-84 RN initial version
* 10-29-87 JCR Multi-thread support
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 05-25-88 PHG Merged DLL and normal versions
* 03-13-90 GJF Made calling type _CALLTYPE1, added #include
* <cruntime.h>, removed #include <register.h> and
* fixed the copyright. Also, cleaned up the formatting
* a bit.
* 04-04-90 GJF Added #include <io.h>.
* 10-01-90 GJF New-style function declarators.
* 12-04-90 GJF Appended Win32 version onto the source with #ifdef-s.
* Two versions should be merged together, the differences
* are trivial.
* 12-06-90 SRW Changed to use _osfile and _osfhnd instead of _osfinfo
* 01-17-91 GJF ANSI naming.
* 02-13-92 GJF Replaced _nfile by _nhandle for Win32.
*
*******************************************************************************/
#include <cruntime.h>
#include <stdio.h>
#include <io.h>
#include <fcntl.h>
#include <errno.h>
#include <msdos.h>
#include <os2dll.h>
#include <stddef.h>
#include <internal.h>
/***
*int _setmode(fh, mode) - set file translation mode
*
*Purpose:
* changes file mode to text/binary, depending on mode arg. this affects
* whether read's and write's on the file translate between CRLF and LF
* or is untranslated
*
*Entry:
* int fh - file handle to change mode on
* int mode - file translation mode (one of O_TEXT and O_BINARY)
*
*Exit:
* returns old file translation mode
* returns -1 and sets errno if fails
*
*Exceptions:
*
*******************************************************************************/
#ifdef MTHREAD /* multi-thread code calls _lk_setmode() */
int _CALLTYPE1 _setmode (
int fh,
int mode
)
{
int retval;
#ifdef _WIN32_
if ( (unsigned)fh >= (unsigned)_nhandle ) {
#else
if (fh < 0 || fh >= _nfile) {
#endif
errno = EBADF;
return(-1);
}
/* lock the file */
_lock_fh(fh);
/* set the text/binary mode */
retval = _setmode_lk(fh, mode);
/* unlock the file */
_unlock_fh(fh);
/* Return to user (_setmode_lk sets errno, if needed) */
return(retval);
}
/***
*_setmode_lk() - Perform core setmode operation
*
*Purpose:
* Core setmode code. Assumes:
* (1) Caller has validated fh to make sure it's in range.
* (2) Caller has locked the file handle.
*
* [See _setmode() description above.]
*
*Entry: [Same as _setmode()]
*
*Exit: [Same as _setmode()]
*
*Exceptions:
*
*******************************************************************************/
int _CALLTYPE1 _setmode_lk (
REG1 int fh,
int mode
)
{
int oldmode;
#else /* non multi-thread code */
int _CALLTYPE1 _setmode (
REG1 int fh,
int mode
)
{
int oldmode;
#ifdef _WIN32_
if ( (unsigned)fh >= (unsigned)_nhandle ) {
#else
if (fh < 0 || fh >= _nfile) {
#endif
errno = EBADF;
return(-1);
}
#endif /* now join common code */
if (!(_osfile[fh] & FOPEN)) {
errno = EBADF;
return(-1);
}
else {
oldmode = _osfile[fh] & FTEXT;
if (mode == _O_BINARY)
_osfile[fh] &= ~FTEXT;
else if (mode == _O_TEXT)
_osfile[fh] |= FTEXT;
else {
errno = EINVAL;
return(-1);
}
}
return(oldmode ? _O_TEXT : _O_BINARY);
}