122 lines
3.6 KiB
C
122 lines
3.6 KiB
C
/***
|
|
*eof.c - test a handle for end of file
|
|
*
|
|
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
|
|
*
|
|
*Purpose:
|
|
* defines _eof() - determine if a file is at eof
|
|
*
|
|
*Revision History:
|
|
* 09-07-83 RN initial version
|
|
* 10-28-87 JCR Multi-thread support
|
|
* 12-11-87 JCR Added "_LOAD_DS" to declaration
|
|
* 05-25-88 PHG DLL replaces normal version
|
|
* 07-11-88 JCR Added REG allocation to declarations
|
|
* 03-12-90 GJF Replaced _LOAD_DS with _CALLTYPE1, added #include
|
|
* <cruntime.h>, removed #include <register.h> and fixed
|
|
* the copyright. Also, cleaned up the formatting a bit.
|
|
* 09-28-90 GJF New-style function declarator.
|
|
* 12-04-90 GJF Improved range check of file handle.
|
|
* 01-16-91 GJF ANSI naming.
|
|
* 02-13-92 GJF Replaced _nfile by _nhandle for Win32.
|
|
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
|
|
* 01-04-95 GJF _WIN32_ -> _WIN32
|
|
* 02-15-95 GJF Appended Mac version of source file (somewhat cleaned
|
|
* up), with appropriate #ifdef-s.
|
|
* 06-27-95 GJF Added check that the file handle is open.
|
|
* 07-08-96 GJF Replaced defined(_WIN32) with !defined(_MAC), and
|
|
* defined(_M_M68K) || defined(_M_MPPC) with
|
|
* defined(_MAC). Removed obsolete REG* macros. Also,
|
|
* detab-ed and cleaned up the format a bit.
|
|
* 12-17-97 GJF Exception-safe locking.
|
|
* 09-23-98 GJF Use _lseeki64_lk so _eof works on BIG files
|
|
* 05-17-99 PML Remove all Macintosh support.
|
|
*
|
|
*******************************************************************************/
|
|
|
|
#include <cruntime.h>
|
|
#include <io.h>
|
|
#include <errno.h>
|
|
#include <stddef.h>
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <internal.h>
|
|
#include <msdos.h>
|
|
#include <mtdll.h>
|
|
|
|
/***
|
|
*int _eof(filedes) - test a file for eof
|
|
*
|
|
*Purpose:
|
|
* see if the file length is the same as the present position. if so, return
|
|
* 1. if not, return 0. if an error occurs, return -1
|
|
*
|
|
*Entry:
|
|
* int filedes - handle of file to test
|
|
*
|
|
*Exit:
|
|
* returns 1 if at eof
|
|
* returns 0 if not at eof
|
|
* returns -1 and sets errno if fails
|
|
*
|
|
*Exceptions:
|
|
*
|
|
*******************************************************************************/
|
|
|
|
int __cdecl _eof (
|
|
int filedes
|
|
)
|
|
{
|
|
__int64 here;
|
|
__int64 end;
|
|
int retval;
|
|
|
|
if ( ((unsigned)filedes >= (unsigned)_nhandle) ||
|
|
!(_osfile(filedes) & FOPEN) )
|
|
{
|
|
errno = EBADF;
|
|
_doserrno = 0;
|
|
return(-1);
|
|
}
|
|
|
|
#ifdef _MT
|
|
|
|
/* Lock the file */
|
|
_lock_fh(filedes);
|
|
__try {
|
|
if ( _osfile(filedes) & FOPEN ) {
|
|
|
|
#endif /* _MT */
|
|
|
|
/* See if the current position equals the end of the file. */
|
|
|
|
if ( ((here = _lseeki64_lk(filedes, 0i64, SEEK_CUR)) == -1i64) ||
|
|
((end = _lseeki64_lk(filedes, 0i64, SEEK_END)) == -1i64) )
|
|
retval = -1;
|
|
else if ( here == end )
|
|
retval = 1;
|
|
else {
|
|
_lseeki64_lk(filedes, here, SEEK_SET);
|
|
retval = 0;
|
|
}
|
|
|
|
#ifdef _MT
|
|
|
|
}
|
|
else {
|
|
errno = EBADF;
|
|
_doserrno = 0;
|
|
retval = -1;
|
|
}
|
|
}
|
|
__finally {
|
|
/* Unlock the file */
|
|
_unlock_fh(filedes);
|
|
}
|
|
|
|
#endif /* _MT */
|
|
|
|
/* Done */
|
|
return(retval);
|
|
}
|