strace/dirent64.c
Dmitry V. Levin de484eced5 Introduce print_quoted_cstring
In many places where kernel expects a NUL-terminated string of length
up to a known fixed limit, e.g. when a NUL-terminated string is
a fixed-size field of a structure, strace does not print the last byte
assuming it is NUL, which is not always the case.

Change output format for such strings to distinguish NUL-terminated
strings from non-NUL-terminated ones: append ellipsis to the output
when the string is not NUL-terminated.

* defs.h (print_quoted_cstring): New prototype.
* util.c (print_quoted_cstring): New function.
(printpathn): Use it instead of print_quoted_string with
QUOTE_0_TERMINATED argument.
* print_fields.h (PRINT_FIELD_CSTRING): Likewise.
* btrfs.c (btrfs_ioctl): Likewise.
* dirent.c (SYS_FUNC(getdents)): Likewise.
* dirent64.c (SYS_FUNC(getdents64)): Likewise.
* print_ifindex.c (print_ifindex): Likewise.
* sysmips.c (SYS_FUNC(sysmips)): Likewise.
* ubi.c (ubi_ioctl): Likewise.
* tests/tests.h (print_quoted_cstring): New prototype.
* tests/print_quoted_string.c (print_quoted_cstring): New function.
* tests/ioctl_block.c (main): Update expected output.
* tests/ioctl_dm.c (main): Likewise.
* tests/ioctl_loop.c (print_loop_info, print_loop_info64): Likewise.
* tests/netlink_crypto.c (test_crypto_msg_newalg): Likewise.
2017-07-24 12:10:54 +00:00

127 lines
3.7 KiB
C

/*
* Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
* Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
* Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
* Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
* Copyright (c) 2005-2015 Dmitry V. Levin <ldv@altlinux.org>
* Copyright (c) 2015-2017 The strace developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "defs.h"
#include <dirent.h>
#include "xlat/dirent_types.h"
#define D_NAME_LEN_MAX 256
SYS_FUNC(getdents64)
{
/* the minimum size of a valid dirent64 structure */
const unsigned int d_name_offset = offsetof(struct dirent64, d_name);
unsigned int i, len, dents = 0;
char *buf;
if (entering(tcp)) {
printfd(tcp, tcp->u_arg[0]);
return 0;
}
const unsigned int count = tcp->u_arg[2];
if (syserror(tcp) || !verbose(tcp)) {
tprints(", ");
printaddr(tcp->u_arg[1]);
tprintf(", %u", count);
return 0;
}
/* Beware of insanely large or too small values in tcp->u_rval */
if (tcp->u_rval > 1024*1024)
len = 1024*1024;
else if (tcp->u_rval < (int) d_name_offset)
len = 0;
else
len = tcp->u_rval;
if (len) {
buf = malloc(len);
if (!buf || umoven(tcp, tcp->u_arg[1], len, buf) < 0) {
tprints(", ");
printaddr(tcp->u_arg[1]);
tprintf(", %u", count);
free(buf);
return 0;
}
} else {
buf = NULL;
}
tprints(",");
if (!abbrev(tcp))
tprints(" [");
for (i = 0; len && i <= len - d_name_offset; ) {
struct dirent64 *d = (struct dirent64 *) &buf[i];
if (!abbrev(tcp)) {
int d_name_len;
if (d->d_reclen >= d_name_offset
&& i + d->d_reclen <= len) {
d_name_len = d->d_reclen - d_name_offset;
} else {
d_name_len = len - i - d_name_offset;
}
if (d_name_len > D_NAME_LEN_MAX)
d_name_len = D_NAME_LEN_MAX;
tprintf("%s{d_ino=%" PRIu64 ", d_off=%" PRId64
", d_reclen=%u, d_type=",
i ? ", " : "",
d->d_ino,
d->d_off,
d->d_reclen);
printxval(dirent_types, d->d_type, "DT_???");
tprints(", d_name=");
print_quoted_cstring(d->d_name, d_name_len);
tprints("}");
}
if (d->d_reclen < d_name_offset) {
tprints_comment("d_reclen < offsetof(struct dirent64, d_name)");
break;
}
i += d->d_reclen;
dents++;
}
if (!abbrev(tcp))
tprints("]");
else
tprintf_comment("%u entries", dents);
tprintf(", %u", count);
free(buf);
return 0;
}