2 * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
3 * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
4 * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
5 * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
6 * Copyright (c) 2002-2005 Roland McGrath <roland@redhat.com>
7 * Copyright (c) 2009 Andreas Schwab <schwab@redhat.com>
8 * Copyright (c) 2012 H.J. Lu <hongjiu.lu@intel.com>
9 * Copyright (c) 2013 Denys Vlasenko <vda.linux@googlemail.com>
10 * Copyright (c) 2014-2016 Dmitry V. Levin <ldv@altlinux.org>
11 * Copyright (c) 2014-2018 The strace developers.
12 * All rights reserved.
14 * SPDX-License-Identifier: LGPL-2.1-or-later
19 #include "xlat/whence_codes.h"
21 /* Linux kernel has exactly one version of lseek:
22 * fs/read_write.c::SYSCALL_DEFINE3(lseek, unsigned, fd, off_t, offset, unsigned, origin)
23 * In kernel, off_t is always the same as (kernel's) long
24 * (see include/uapi/asm-generic/posix_types.h).
25 * Use test/x32_lseek.c to test lseek decoding.
29 printfd(tcp, tcp->u_arg[0]);
33 #ifndef current_klongsize
34 if (current_klongsize < sizeof(kernel_long_t)) {
35 offset = (int) tcp->u_arg[1];
37 #endif /* !current_klongsize */
39 offset = tcp->u_arg[1];
42 tprintf(", %" PRI_kld ", ", offset);
44 printxval(whence_codes, tcp->u_arg[2], "SEEK_???");
49 /* llseek syscall takes explicitly two ulong arguments hi, lo,
50 * rather than one 64-bit argument for which ULONG_LONG works
51 * appropriate for the native byte order.
53 * See kernel's fs/read_write.c::SYSCALL_DEFINE5(llseek, ...)
55 * hi,lo are "unsigned longs" and combined exactly this way in kernel:
56 * ((loff_t) hi << 32) | lo
57 * Note that for architectures with kernel's long wider than userspace long
58 * (such as x32), combining code will use *kernel's*, i.e. *wide* longs
64 printfd(tcp, tcp->u_arg[0]);
66 ((long long) tcp->u_arg[1] << 32)
67 | ((long long) tcp->u_arg[2]));
69 printnum_int64(tcp, tcp->u_arg[3], "%" PRIu64);
71 printxval(whence_codes, tcp->u_arg[4], "SEEK_???");