windows-nt/Source/XPSP1/NT/base/crts/crtw32/lowio/fstat.c
2020-09-26 16:20:57 +08:00

332 lines
12 KiB
C

/***
*fstat.c - return file status info
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines fstat() - return file status info
*
*Revision History:
* 03-??-84 RLB Module created
* 05-??-84 DCW Added register variables
* 05-19-86 SKS Ported to OS/2
* 05-21-87 SKS Cleaned up declarations and include files
* 11-01-87 JCR Multi-thread support
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 05-25-88 PHG Merged DLL and normal version
* 10-03-88 GJF Adapted for new DOSCALLS.H, DOSTYPES.H.
* 10-04-88 JCR 386: Removed 'far' keyword
* 10-10-88 GJF Made API names match DOSCALLS.H
* 11-07-88 GJF Cleanup, now specific to 386
* 04-13-89 JCR New syscall interface
* 05-23-89 PHG Added mask to ignore network bit when testing handle
* type
* 05-25-89 JCR 386 OS/2 calls use '_syscall' calling convention
* 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.
* 04-04-90 GJF Removed #include <dos.h>.
* 07-24-90 SBM Removed '32' from API names
* 08-13-90 SBM Compiles cleanly with -W3
* 09-28-90 GJF New-style function declarator.
* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
* 12-06-90 SRW Added _CRUISER_ and _WIN32 conditionals.
* 01-21-91 GJF ANSI naming.
* 04-26-91 SRW Implemented fstat for _WIN32_ and removed level 3
* warnings.
* 02-13-92 GJF Replaced _nfile by _nhandle for Win32.
* 05-27-92 SKS File Creation and File Last Access timestamps may be 0
* on some file systems (e.g. FAT) in which case the
* File Last Write time should be used instead.
* 06-04-92 SKS Changed comment that used to say "This is a BUG!"
* to explain that this value cannot be computed on
* OS/2 or NT. Only MS-DOS provides this functionality.
* The drive number is not valid for UNC names.
* 06-25-92 GJF Use GetFileInformationByHandle API, also cleaned up
* formatting of Win32 verson [_WIN32_].
* 08-18-92 SKS Add a call to FileTimeToLocalFileTime
* as a temporary fix until _dtoxtime takes UTC
* 08-20-92 GJF Merged two changes above.
* 12-16-92 GJF Win32 GetFileInformationByHandle API doesn't like
* device or pipe handles. Use _S_IFIFO for pipes.
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* 04-06-93 GJF Made computation of file times consistent with _stat().
* 07-21-93 GJF Converted from using __gmtotime_t to __loctotime_t.
* This undoes part of the change made on 04-06-92
* 12-28-94 GJF Added _fstati64.
* 02-15-95 GJF Appended Mac version of source file (somewhat cleaned
* up), with appropriate #ifdef-s.
* 06-11-95 GJF Replaced _osfhnd[] with _osfhnd() (macro referencing
* field in ioinfo struct).
* 06-27-95 GJF Added check that the file handle is open.
* 09-25-95 GJF __loctotime_t now takes a DST flag, pass -1 in this
* slot to indicate DST is undetermined.
* 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.
* 12-19-97 GJF Exception-safe locking.
* 05-17-99 PML Remove all Macintosh support.
* 10-27-99 GB Remove #inlcude <dostypes.h>
*
*******************************************************************************/
#include <cruntime.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <msdos.h>
#include <io.h>
#include <internal.h>
#include <stddef.h>
#include <oscalls.h>
#include <stdio.h>
#include <mtdll.h>
#include <time.h>
#define IO_DEVNBR 0x3f
/***
*int _fstat(fildes, buf) - fills supplied buffer with status info
*
*Purpose:
* Fills the supplied buffer with status information on the
* file represented by the specified file designator.
* WARNING: the dev/rdev fields are zero for files. This is
* incompatible with DOS 3 version of this routine.
*
* Note: We cannot directly use the file time stamps returned in the
* BY_HANDLE_FILE_INFORMATION structure. The values are supposedly in
* system time and system time is ambiguously defined (it is UTC for
* Windows NT, local time for Win32S and probably local time for
* Win32C). Therefore, these values must be converted to local time
* before than can be used.
*
*Entry:
* int fildes - file descriptor
* struct stat *buf - buffer to store result in
*
*Exit:
* fills in buffer pointed to by buf
* returns 0 if successful
* returns -1 and sets errno if unsuccessful
*
*Exceptions:
*
*******************************************************************************/
#ifdef _USE_INT64
int __cdecl _fstati64 (
int fildes,
struct _stati64 *buf
)
#else /* ndef _USE_INT64 */
int __cdecl _fstat (
int fildes,
struct _stat *buf
)
#endif /* _USE_INT64 */
{
int isdev; /* 0 for a file, 1 for a device */
int retval = 0; /* assume good return */
BY_HANDLE_FILE_INFORMATION bhfi;
FILETIME LocalFTime;
SYSTEMTIME SystemTime;
if ( ((unsigned)fildes >= (unsigned)_nhandle) ||
!(_osfile(fildes) & FOPEN) )
{
errno = EBADF;
return(-1);
}
#ifdef _MT
/* Lock the file */
_lock_fh(fildes);
__try {
if ( !(_osfile(fildes) & FOPEN) ) {
errno = EBADF;
retval = -1;
goto done;
}
#endif /* _MT */
/* Find out what kind of handle underlies filedes
*/
isdev = GetFileType((HANDLE)_osfhnd(fildes)) & ~FILE_TYPE_REMOTE;
if ( isdev != FILE_TYPE_DISK ) {
/* not a disk file. probably a device or pipe
*/
if ( (isdev == FILE_TYPE_CHAR) || (isdev == FILE_TYPE_PIPE) ) {
/* treat pipes and devices similarly. no further info is
* available from any API, so set the fields as reasonably
* as possible and return.
*/
if ( isdev == FILE_TYPE_CHAR )
buf->st_mode = _S_IFCHR;
else
buf->st_mode = _S_IFIFO;
buf->st_rdev = buf->st_dev = (_dev_t)fildes;
buf->st_nlink = 1;
buf->st_uid = buf->st_gid = buf->st_ino = 0;
buf->st_atime = buf->st_mtime = buf->st_ctime = 0;
if ( isdev == FILE_TYPE_CHAR ) {
#ifdef _USE_INT64
buf->st_size = 0i64;
#else /* ndef _USE_INT64 */
buf->st_size = 0;
#endif /* _USE_INT64 */
}
else {
unsigned long ulAvail;
int rc;
rc = PeekNamedPipe((HANDLE)_osfhnd(fildes),
NULL,
0,
NULL,
&ulAvail,
NULL);
if (rc) {
buf->st_size = (_off_t)ulAvail;
}
else {
buf->st_size = (_off_t)0;
}
}
goto done;
}
else if ( isdev == FILE_TYPE_UNKNOWN ) {
errno = EBADF;
retval = -1;
goto done; /* join common return code */
}
else {
/* according to the documentation, this cannot happen, but
* play it safe anyway.
*/
_dosmaperr(GetLastError());
retval = -1;
goto done;
}
}
/* set the common fields
*/
buf->st_ino = buf->st_uid = buf->st_gid = buf->st_mode = 0;
buf->st_nlink = 1;
/* use the file handle to get all the info about the file
*/
if ( !GetFileInformationByHandle((HANDLE)_osfhnd(fildes), &bhfi) ) {
_dosmaperr(GetLastError());
retval = -1;
goto done;
}
if ( bhfi.dwFileAttributes & FILE_ATTRIBUTE_READONLY )
buf->st_mode |= (_S_IREAD + (_S_IREAD >> 3) + (_S_IREAD >> 6));
else
buf->st_mode |= ((_S_IREAD|_S_IWRITE) + ((_S_IREAD|_S_IWRITE) >> 3)
+ ((_S_IREAD|_S_IWRITE) >> 6));
/* set file date fields
*/
if ( !FileTimeToLocalFileTime( &(bhfi.ftLastWriteTime), &LocalFTime )
|| !FileTimeToSystemTime( &LocalFTime, &SystemTime ) )
{
retval = -1;
goto done;
}
buf->st_mtime = __loctotime_t(SystemTime.wYear,
SystemTime.wMonth,
SystemTime.wDay,
SystemTime.wHour,
SystemTime.wMinute,
SystemTime.wSecond,
-1);
if ( bhfi.ftLastAccessTime.dwLowDateTime ||
bhfi.ftLastAccessTime.dwHighDateTime )
{
if ( !FileTimeToLocalFileTime( &(bhfi.ftLastAccessTime),
&LocalFTime ) ||
!FileTimeToSystemTime( &LocalFTime, &SystemTime ) )
{
retval = -1;
goto done;
}
buf->st_atime = __loctotime_t(SystemTime.wYear,
SystemTime.wMonth,
SystemTime.wDay,
SystemTime.wHour,
SystemTime.wMinute,
SystemTime.wSecond,
-1);
}
else
buf->st_atime = buf->st_mtime;
if ( bhfi.ftCreationTime.dwLowDateTime ||
bhfi.ftCreationTime.dwHighDateTime )
{
if ( !FileTimeToLocalFileTime( &(bhfi.ftCreationTime),
&LocalFTime ) ||
!FileTimeToSystemTime( &LocalFTime, &SystemTime ) )
{
retval = -1;
goto done;
}
buf->st_ctime = __loctotime_t(SystemTime.wYear,
SystemTime.wMonth,
SystemTime.wDay,
SystemTime.wHour,
SystemTime.wMinute,
SystemTime.wSecond,
-1);
}
else
buf->st_ctime = buf->st_mtime;
#ifdef _USE_INT64
buf->st_size = ((__int64)(bhfi.nFileSizeHigh)) * (0x100000000i64) +
(__int64)(bhfi.nFileSizeLow);
#else /* ndef _USE_INT64 */
buf->st_size = bhfi.nFileSizeLow;
#endif /* _USE_INT64 */
buf->st_mode |= _S_IFREG;
/* On DOS, this field contains the drive number, but
* the drive number is not available on this platform.
* Also, for UNC network names, there is no drive number.
*/
buf->st_rdev = buf->st_dev = 0;
/* Common return code */
done:
#ifdef _MT
; }
__finally {
_unlock_fh(fildes);
}
#endif /* _MT */
return(retval);
}