1 /*
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) 2014-2015 Dmitry V. Levin <ldv@altlinux.org>
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #include "defs.h"
37
38 #include "xlat/whence_codes.h"
39
40 /* Linux kernel has exactly one version of lseek:
41 * fs/read_write.c::SYSCALL_DEFINE3(lseek, unsigned, fd, off_t, offset, unsigned, origin)
42 * In kernel, off_t is always the same as (kernel's) long
43 * (see include/uapi/asm-generic/posix_types.h),
44 * which means that on x32 we need to use tcp->ext_arg[N] to get offset argument.
45 * Use test/x32_lseek.c to test lseek decoding.
46 */
47 #if defined(LINUX_MIPSN32) || defined(X32)
SYS_FUNC(lseek)48 SYS_FUNC(lseek)
49 {
50 long long offset;
51 int whence;
52
53 printfd(tcp, tcp->u_arg[0]);
54 # ifdef X32
55 /* tcp->ext_arg is not initialized for i386 personality */
56 if (current_personality == 1)
57 offset = tcp->u_arg[1];
58 else
59 # endif
60 offset = tcp->ext_arg[1];
61 whence = tcp->u_arg[2];
62 if (whence == SEEK_SET)
63 tprintf(", %llu, ", offset);
64 else
65 tprintf(", %lld, ", offset);
66 printxval(whence_codes, whence, "SEEK_???");
67
68 return RVAL_DECODED | RVAL_LUDECIMAL;
69 }
70 #else
SYS_FUNC(lseek)71 SYS_FUNC(lseek)
72 {
73 long offset;
74 int whence;
75
76 printfd(tcp, tcp->u_arg[0]);
77 offset = tcp->u_arg[1];
78 whence = tcp->u_arg[2];
79 if (whence == SEEK_SET)
80 tprintf(", %lu, ", offset);
81 else
82 tprintf(", %ld, ", offset);
83 printxval(whence_codes, whence, "SEEK_???");
84
85 return RVAL_DECODED | RVAL_UDECIMAL;
86 }
87 #endif
88
89 /* llseek syscall takes explicitly two ulong arguments hi, lo,
90 * rather than one 64-bit argument for which LONG_LONG works
91 * appropriate for the native byte order.
92 *
93 * See kernel's fs/read_write.c::SYSCALL_DEFINE5(llseek, ...)
94 *
95 * hi,lo are "unsigned longs" and combined exactly this way in kernel:
96 * ((loff_t) hi << 32) | lo
97 * Note that for architectures with kernel's long wider than userspace long
98 * (such as x32), combining code will use *kernel's*, i.e. *wide* longs
99 * for hi and lo. We would need to use tcp->ext_arg[N] on x32...
100 * ...however, x32 (and x86_64) does not _have_ llseek syscall as such.
101 */
SYS_FUNC(llseek)102 SYS_FUNC(llseek)
103 {
104 if (entering(tcp)) {
105 printfd(tcp, tcp->u_arg[0]);
106 if (tcp->u_arg[4] == SEEK_SET)
107 tprintf(", %llu, ",
108 ((long long) tcp->u_arg[1]) << 32 |
109 (unsigned long long) (unsigned) tcp->u_arg[2]);
110 else
111 tprintf(", %lld, ",
112 ((long long) tcp->u_arg[1]) << 32 |
113 (unsigned long long) (unsigned) tcp->u_arg[2]);
114 } else {
115 printnum_int64(tcp, tcp->u_arg[3], "%" PRIu64);
116 tprints(", ");
117 printxval(whence_codes, tcp->u_arg[4], "SEEK_???");
118 }
119 return 0;
120 }
121