]> granicus.if.org Git - strace/blob - io.c
Fix decoding and dumping of readv syscall in case of short read
[strace] / io.c
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  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30
31 #include "defs.h"
32 #include <fcntl.h>
33 #include <sys/uio.h>
34
35 SYS_FUNC(read)
36 {
37         if (entering(tcp)) {
38                 printfd(tcp, tcp->u_arg[0]);
39                 tprints(", ");
40         } else {
41                 if (syserror(tcp))
42                         printaddr(tcp->u_arg[1]);
43                 else
44                         printstr(tcp, tcp->u_arg[1], tcp->u_rval);
45                 tprintf(", %lu", tcp->u_arg[2]);
46         }
47         return 0;
48 }
49
50 SYS_FUNC(write)
51 {
52         printfd(tcp, tcp->u_arg[0]);
53         tprints(", ");
54         printstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
55         tprintf(", %lu", tcp->u_arg[2]);
56
57         return RVAL_DECODED;
58 }
59
60 /*
61  * data_size limits the cumulative size of printed data.
62  * Example: recvmsg returing a short read.
63  */
64 void
65 tprint_iov_upto(struct tcb *tcp, unsigned long len, unsigned long addr, int decode_iov, unsigned long data_size)
66 {
67         unsigned long iov[2];
68         unsigned long size, cur, end, abbrev_end;
69         const unsigned long sizeof_iov = current_wordsize * 2;
70
71         if (!len) {
72                 tprints("[]");
73                 return;
74         }
75         size = len * sizeof_iov;
76         end = addr + size;
77         if (!verbose(tcp) || (exiting(tcp) && syserror(tcp)) ||
78             !addr || size / sizeof_iov != len || end < addr) {
79                 printaddr(addr);
80                 return;
81         }
82         if (abbrev(tcp)) {
83                 abbrev_end = addr + max_strlen * sizeof_iov;
84                 if (abbrev_end < addr)
85                         abbrev_end = end;
86         } else {
87                 abbrev_end = end;
88         }
89         tprints("[");
90         for (cur = addr; cur < end; cur += sizeof_iov) {
91                 if (cur > addr)
92                         tprints(", ");
93                 if (cur >= abbrev_end) {
94                         tprints("...");
95                         break;
96                 }
97                 if (umove_ulong_array_or_printaddr(tcp, cur, iov,
98                                                    ARRAY_SIZE(iov)))
99                         break;
100                 tprints("{");
101                 if (decode_iov) {
102                         unsigned long len = iov[1];
103                         if (len > data_size)
104                                 len = data_size;
105                         data_size -= len;
106                         printstr(tcp, iov[0], len);
107                 } else
108                         printaddr(iov[0]);
109                 tprintf(", %lu}", iov[1]);
110         }
111         tprints("]");
112 }
113
114 void
115 tprint_iov(struct tcb *tcp, unsigned long len, unsigned long addr, int decode_iov)
116 {
117         tprint_iov_upto(tcp, len, addr, decode_iov, (unsigned long) -1L);
118 }
119
120 SYS_FUNC(readv)
121 {
122         if (entering(tcp)) {
123                 printfd(tcp, tcp->u_arg[0]);
124                 tprints(", ");
125         } else {
126                 tprint_iov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1], 1,
127                                 tcp->u_rval);
128                 tprintf(", %lu", tcp->u_arg[2]);
129         }
130         return 0;
131 }
132
133 SYS_FUNC(writev)
134 {
135         printfd(tcp, tcp->u_arg[0]);
136         tprints(", ");
137         tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
138         tprintf(", %lu", tcp->u_arg[2]);
139
140         return RVAL_DECODED;
141 }
142
143 /* The SH4 ABI does allow long longs in odd-numbered registers, but
144    does not allow them to be split between registers and memory - and
145    there are only four argument registers for normal functions.  As a
146    result pread takes an extra padding argument before the offset.  This
147    was changed late in the 2.4 series (around 2.4.20).  */
148 #if defined(SH)
149 #define PREAD_OFFSET_ARG 4
150 #else
151 #define PREAD_OFFSET_ARG 3
152 #endif
153
154 SYS_FUNC(pread)
155 {
156         if (entering(tcp)) {
157                 printfd(tcp, tcp->u_arg[0]);
158                 tprints(", ");
159         } else {
160                 if (syserror(tcp))
161                         printaddr(tcp->u_arg[1]);
162                 else
163                         printstr(tcp, tcp->u_arg[1], tcp->u_rval);
164                 tprintf(", %lu, ", tcp->u_arg[2]);
165                 printllval(tcp, "%llu", PREAD_OFFSET_ARG);
166         }
167         return 0;
168 }
169
170 SYS_FUNC(pwrite)
171 {
172         printfd(tcp, tcp->u_arg[0]);
173         tprints(", ");
174         printstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
175         tprintf(", %lu, ", tcp->u_arg[2]);
176         printllval(tcp, "%llu", PREAD_OFFSET_ARG);
177
178         return RVAL_DECODED;
179 }
180
181 static void
182 print_llu_from_low_high_val(struct tcb *tcp, int arg)
183 {
184 #if SIZEOF_LONG == SIZEOF_LONG_LONG
185 # if SUPPORTED_PERSONALITIES > 1
186 #  ifdef X86_64
187         if (current_personality != 1)
188 #  else
189         if (current_wordsize == sizeof(long))
190 #  endif
191 # endif
192                 tprintf("%lu", (unsigned long) tcp->u_arg[arg]);
193 # if SUPPORTED_PERSONALITIES > 1
194         else
195                 tprintf("%lu",
196                         ((unsigned long) tcp->u_arg[arg + 1] << current_wordsize * 8)
197                         | (unsigned long) tcp->u_arg[arg]);
198 # endif
199 #else
200 # ifdef X32
201         if (current_personality == 0)
202                 tprintf("%llu", (unsigned long long) tcp->ext_arg[arg]);
203         else
204 # endif
205         tprintf("%llu",
206                 ((unsigned long long) (unsigned long) tcp->u_arg[arg + 1] << sizeof(long) * 8)
207                 | (unsigned long long) (unsigned long) tcp->u_arg[arg]);
208 #endif
209 }
210
211 SYS_FUNC(preadv)
212 {
213         if (entering(tcp)) {
214                 printfd(tcp, tcp->u_arg[0]);
215                 tprints(", ");
216         } else {
217                 tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
218                 tprintf(", %lu, ", tcp->u_arg[2]);
219                 print_llu_from_low_high_val(tcp, 3);
220         }
221         return 0;
222 }
223
224 SYS_FUNC(pwritev)
225 {
226         printfd(tcp, tcp->u_arg[0]);
227         tprints(", ");
228         tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
229         tprintf(", %lu, ", tcp->u_arg[2]);
230         print_llu_from_low_high_val(tcp, 3);
231
232         return RVAL_DECODED;
233 }
234
235 #include "xlat/splice_flags.h"
236
237 SYS_FUNC(tee)
238 {
239         /* int fd_in */
240         printfd(tcp, tcp->u_arg[0]);
241         tprints(", ");
242         /* int fd_out */
243         printfd(tcp, tcp->u_arg[1]);
244         tprints(", ");
245         /* size_t len */
246         tprintf("%lu, ", tcp->u_arg[2]);
247         /* unsigned int flags */
248         printflags(splice_flags, tcp->u_arg[3], "SPLICE_F_???");
249
250         return RVAL_DECODED;
251 }
252
253 SYS_FUNC(splice)
254 {
255         /* int fd_in */
256         printfd(tcp, tcp->u_arg[0]);
257         tprints(", ");
258         /* loff_t *off_in */
259         printnum_int64(tcp, tcp->u_arg[1], "%" PRIu64);
260         tprints(", ");
261         /* int fd_out */
262         printfd(tcp, tcp->u_arg[2]);
263         tprints(", ");
264         /* loff_t *off_out */
265         printnum_int64(tcp, tcp->u_arg[3], "%" PRIu64);
266         tprints(", ");
267         /* size_t len */
268         tprintf("%lu, ", tcp->u_arg[4]);
269         /* unsigned int flags */
270         printflags(splice_flags, tcp->u_arg[5], "SPLICE_F_???");
271
272         return RVAL_DECODED;
273 }
274
275 SYS_FUNC(vmsplice)
276 {
277         /* int fd */
278         printfd(tcp, tcp->u_arg[0]);
279         tprints(", ");
280         /* const struct iovec *iov, unsigned long nr_segs */
281         tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
282         tprintf(", %lu, ", tcp->u_arg[2]);
283         /* unsigned int flags */
284         printflags(splice_flags, tcp->u_arg[3], "SPLICE_F_???");
285
286         return RVAL_DECODED;
287 }