2020-09-30 17:12:29 +02:00

157 lines
3.9 KiB
C

/***
*dup.c - OS/2 duplicate file handles
*
* Copyright (c) 1989-1992, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines _dup() - duplicate file handles
*
*Revision History:
* 06-09-89 PHG Module created, based on asm version
* 03-12-90 GJF Made calling type _CALLTYPE2 (for now), added #include
* <cruntime.h> and fixed the copyright. Also, cleaned up
* the formatting a bit.
* 04-03-90 GJF Now _CALLTYPE1.
* 07-24-90 SBM Removed '32' from API names
* 08-14-90 SBM Compiles cleanly with -W3
* 09-28-90 GJF New-style function declarator.
* 12-04-90 GJF Appended Win32 version onto the source with #ifdef-s.
* It is enough different that there is little point in
* trying to more closely merge the two versions.
* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
* 12-06-90 SRW Changed to use _osfile and _osfhnd instead of _osfinfo
* 01-16-91 GJF ANSI naming.
* 02-07-91 SRW Changed to call _get_osfhandle [_WIN32_]
* 02-18-91 SRW Changed to call _free_osfhnd [_WIN32_]
* 02-25-91 SRW Renamed _get_free_osfhnd to be _alloc_osfhnd [_WIN32_]
* 02-13-92 GJF Replaced _nfile by _nhandle for Win32.
* 09-03-92 GJF Added explicit check for unopened handles [_WIN32_].
*
*******************************************************************************/
#include <cruntime.h>
#include <oscalls.h>
#include <errno.h>
#include <os2dll.h>
#include <io.h>
#include <msdos.h>
#include <internal.h>
#include <stdlib.h>
/***
*int _dup(fh) - duplicate a file handle
*
*Purpose:
* Assigns another file handle to the file associated with the
* handle fh. The next available file handle is assigned.
*
* Multi-thread: Be sure not to hold two file handle locks
* at the same time!
*
*Entry:
* int fh - file handle to duplicate
*
*Exit:
* returns new file handle if successful
* returns -1 (and sets errno) if fails
*
*Exceptions:
*
*******************************************************************************/
int _CALLTYPE1 _dup (
int fh
)
{
ULONG dosretval; /* OS/2 return value */
int newfh; /* variable for new file handle */
char fileinfo; /* _osfile info for file */
/* validate file handle */
#ifdef _WIN32_
if ( ((unsigned)fh >= (unsigned)_nhandle) ||
!(_osfile[fh] & FOPEN) ) {
#else
if ((unsigned)fh >= (unsigned)_nfile) {
#endif
errno = EBADF;
_doserrno = 0; /* no OS/2 error */
return -1;
}
_lock_fh(fh); /* lock file handle */
fileinfo = _osfile[fh]; /* get file info for file */
/* create duplicate handle */
#ifdef _CRUISER_
newfh = -1; /* ask for new handle */
dosretval = DOSDUPHANDLE(fh, &newfh);
/* validate range of new handle */
if (dosretval == 0 && (unsigned)newfh >= (unsigned)_nfile) {
/* file handle is not in range -- close it and return error */
_doserrno = DOSCLOSE(newfh);
errno = EMFILE;
_unlock_fh(fh);
return -1;
}
#else /* ndef _CRUISER_ */
#ifdef _WIN32_
{
long new_osfhandle;
if ( (newfh = _alloc_osfhnd()) == -1 ) {
errno = EMFILE; /* too many files error */
_doserrno = 0L; /* not an OS error */
_unlock_fh(fh);
return -1; /* return error to caller */
}
/*
* duplicate the file handle
*/
if ( !(DuplicateHandle(GetCurrentProcess(),
(HANDLE)_get_osfhandle(fh),
GetCurrentProcess(),
(PHANDLE)&new_osfhandle,
0L,
TRUE,
DUPLICATE_SAME_ACCESS)) )
{
dosretval = GetLastError();
}
else {
_set_osfhnd(newfh, new_osfhandle);
dosretval = 0;
}
}
_unlock_fh(newfh);
#else /* ndef _WIN32_ */
#error ERROR - ONLY CRUISER OR WIN32 TARGET SUPPORTED!
#endif /* _WIN32_ */
#endif /* _CRUISER_ */
_unlock_fh(fh); /* unlock file handle */
if (dosretval) {
/* OS/2 error -- map and return */
_dosmaperr(dosretval);
return -1;
}
/* copy _osfile info */
_osfile[newfh] = fileinfo;
return newfh;
}