granicus.if.org Git - strace/blob - 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                         printstrn(tcp, tcp->u_arg[1], tcp->u_rval);
  45                 tprintf(", %" PRI_klu, 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         printstrn(tcp, tcp->u_arg[1], tcp->u_arg[2]);
  55         tprintf(", %" PRI_klu, tcp->u_arg[2]);
  56
  57         return RVAL_DECODED;
  58 }
  59
  60 struct print_iovec_config {
  61         enum iov_decode decode_iov;
  62         kernel_ulong_t data_size;
  63 };
  64
  65 static bool
  66 print_iovec(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
  67 {
  68         const kernel_ulong_t *iov;
  69         kernel_ulong_t iov_buf[2], len;
  70         struct print_iovec_config *c = data;
  71
  72         if (elem_size < sizeof(iov_buf)) {
  73                 iov_buf[0] = ((unsigned int *) elem_buf)[0];
  74                 iov_buf[1] = ((unsigned int *) elem_buf)[1];
  75                 iov = iov_buf;
  76         } else {
  77                 iov = elem_buf;
  78         }
  79
  80         tprints("{iov_base=");
  81
  82         len = iov[1];
  83
  84         switch (c->decode_iov) {
  85                 case IOV_DECODE_STR:
  86                         if (len > c->data_size)
  87                                 len = c->data_size;
  88                         if (c->data_size != (kernel_ulong_t) -1)
  89                                 c->data_size -= len;
  90                         printstrn(tcp, iov[0], len);
  91                         break;
  92                 case IOV_DECODE_NETLINK:
  93                         if (len > c->data_size)
  94                                 len = c->data_size;
  95                         if (c->data_size != (kernel_ulong_t) -1)
  96                                 c->data_size -= len;
  97                         decode_netlink(tcp, iov[0], iov[1]);
  98                         break;
  99                 default:
 100                         printaddr(iov[0]);
 101                         break;
 102         }
 103
 104         tprintf(", iov_len=%" PRI_klu "}", iov[1]);
 105
 106         return true;
 107 }
 108
 109 /*
 110  * data_size limits the cumulative size of printed data.
 111  * Example: recvmsg returing a short read.
 112  */
 113 void
 114 tprint_iov_upto(struct tcb *const tcp, const kernel_ulong_t len,
 115                 const kernel_ulong_t addr, const enum iov_decode decode_iov,
 116                 const kernel_ulong_t data_size)
 117 {
 118         kernel_ulong_t iov[2];
 119         struct print_iovec_config config =
 120                 { .decode_iov = decode_iov, .data_size = data_size };
 121
 122         print_array(tcp, addr, len, iov, current_wordsize * 2,
 123                     umoven_or_printaddr_ignore_syserror, print_iovec, &config);
 124 }
 125
 126 SYS_FUNC(readv)
 127 {
 128         if (entering(tcp)) {
 129                 printfd(tcp, tcp->u_arg[0]);
 130                 tprints(", ");
 131         } else {
 132                 tprint_iov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1],
 133                                 syserror(tcp) ? IOV_DECODE_ADDR :
 134                                 IOV_DECODE_STR, tcp->u_rval);
 135                 tprintf(", %" PRI_klu, tcp->u_arg[2]);
 136         }
 137         return 0;
 138 }
 139
 140 SYS_FUNC(writev)
 141 {
 142         printfd(tcp, tcp->u_arg[0]);
 143         tprints(", ");
 144         tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], IOV_DECODE_STR);
 145         tprintf(", %" PRI_klu, tcp->u_arg[2]);
 146
 147         return RVAL_DECODED;
 148 }
 149
 150 SYS_FUNC(pread)
 151 {
 152         if (entering(tcp)) {
 153                 printfd(tcp, tcp->u_arg[0]);
 154                 tprints(", ");
 155         } else {
 156                 if (syserror(tcp))
 157                         printaddr(tcp->u_arg[1]);
 158                 else
 159                         printstrn(tcp, tcp->u_arg[1], tcp->u_rval);
 160                 tprintf(", %" PRI_klu ", ", tcp->u_arg[2]);
 161                 printllval(tcp, "%lld", 3);
 162         }
 163         return 0;
 164 }
 165
 166 SYS_FUNC(pwrite)
 167 {
 168         printfd(tcp, tcp->u_arg[0]);
 169         tprints(", ");
 170         printstrn(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 171         tprintf(", %" PRI_klu ", ", tcp->u_arg[2]);
 172         printllval(tcp, "%lld", 3);
 173
 174         return RVAL_DECODED;
 175 }
 176
 177 static void
 178 print_lld_from_low_high_val(struct tcb *tcp, int arg)
 179 {
 180 #if SIZEOF_KERNEL_LONG_T > 4
 181 # ifndef current_klongsize
 182         if (current_klongsize < SIZEOF_KERNEL_LONG_T) {
 183                 tprintf("%" PRI_kld, (tcp->u_arg[arg + 1] << 32)
 184                                | tcp->u_arg[arg]);
 185         } else
 186 # endif /* !current_klongsize */
 187         {
 188                 tprintf("%" PRI_kld, tcp->u_arg[arg]);
 189         }
 190 #else /* SIZEOF_KERNEL_LONG_T == 4 */
 191         tprintf("%lld",
 192                   ((long long) tcp->u_arg[arg + 1] << 32)
 193                 | ((long long) tcp->u_arg[arg]));
 194 #endif
 195 }
 196
 197 #include "xlat/rwf_flags.h"
 198
 199 static int
 200 do_preadv(struct tcb *tcp, const int flags_arg)
 201 {
 202         if (entering(tcp)) {
 203                 printfd(tcp, tcp->u_arg[0]);
 204                 tprints(", ");
 205         } else {
 206                 kernel_ulong_t len =
 207                         truncate_kulong_to_current_wordsize(tcp->u_arg[2]);
 208
 209                 tprint_iov_upto(tcp, len, tcp->u_arg[1],
 210                                 syserror(tcp) ? IOV_DECODE_ADDR :
 211                                 IOV_DECODE_STR, tcp->u_rval);
 212                 tprintf(", %" PRI_klu ", ", len);
 213                 print_lld_from_low_high_val(tcp, 3);
 214                 if (flags_arg >= 0) {
 215                         tprints(", ");
 216                         printflags(rwf_flags, tcp->u_arg[flags_arg], "RWF_???");
 217                 }
 218         }
 219         return 0;
 220 }
 221
 222 SYS_FUNC(preadv)
 223 {
 224         return do_preadv(tcp, -1);
 225 }
 226
 227 SYS_FUNC(preadv2)
 228 {
 229         return do_preadv(tcp, 5);
 230 }
 231
 232 static int
 233 do_pwritev(struct tcb *tcp, const int flags_arg)
 234 {
 235         kernel_ulong_t len =
 236                 truncate_kulong_to_current_wordsize(tcp->u_arg[2]);
 237
 238         printfd(tcp, tcp->u_arg[0]);
 239         tprints(", ");
 240         tprint_iov(tcp, len, tcp->u_arg[1], IOV_DECODE_STR);
 241         tprintf(", %" PRI_klu ", ", len);
 242         print_lld_from_low_high_val(tcp, 3);
 243         if (flags_arg >= 0) {
 244                 tprints(", ");
 245                 printflags(rwf_flags, tcp->u_arg[flags_arg], "RWF_???");
 246         }
 247
 248         return RVAL_DECODED;
 249 }
 250
 251 SYS_FUNC(pwritev)
 252 {
 253         return do_pwritev(tcp, -1);
 254 }
 255
 256 SYS_FUNC(pwritev2)
 257 {
 258         return do_pwritev(tcp, 5);
 259 }
 260
 261 #include "xlat/splice_flags.h"
 262
 263 SYS_FUNC(tee)
 264 {
 265         /* int fd_in */
 266         printfd(tcp, tcp->u_arg[0]);
 267         tprints(", ");
 268         /* int fd_out */
 269         printfd(tcp, tcp->u_arg[1]);
 270         tprints(", ");
 271         /* size_t len */
 272         tprintf("%" PRI_klu ", ", tcp->u_arg[2]);
 273         /* unsigned int flags */
 274         printflags(splice_flags, tcp->u_arg[3], "SPLICE_F_???");
 275
 276         return RVAL_DECODED;
 277 }
 278
 279 SYS_FUNC(splice)
 280 {
 281         /* int fd_in */
 282         printfd(tcp, tcp->u_arg[0]);
 283         tprints(", ");
 284         /* loff_t *off_in */
 285         printnum_int64(tcp, tcp->u_arg[1], "%" PRId64);
 286         tprints(", ");
 287         /* int fd_out */
 288         printfd(tcp, tcp->u_arg[2]);
 289         tprints(", ");
 290         /* loff_t *off_out */
 291         printnum_int64(tcp, tcp->u_arg[3], "%" PRId64);
 292         tprints(", ");
 293         /* size_t len */
 294         tprintf("%" PRI_klu ", ", tcp->u_arg[4]);
 295         /* unsigned int flags */
 296         printflags(splice_flags, tcp->u_arg[5], "SPLICE_F_???");
 297
 298         return RVAL_DECODED;
 299 }
 300
 301 SYS_FUNC(vmsplice)
 302 {
 303         /* int fd */
 304         printfd(tcp, tcp->u_arg[0]);
 305         tprints(", ");
 306         /* const struct iovec *iov, unsigned long nr_segs */
 307         tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], IOV_DECODE_STR);
 308         tprintf(", %" PRI_klu ", ", tcp->u_arg[2]);
 309         /* unsigned int flags */
 310         printflags(splice_flags, tcp->u_arg[3], "SPLICE_F_???");
 311
 312         return RVAL_DECODED;
 313 }