granicus.if.org Git - strace/blob - desc.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
  33 SYS_FUNC(close)
  34 {
  35         printfd(tcp, tcp->u_arg[0]);
  36
  37         return RVAL_DECODED;
  38 }
  39
  40 SYS_FUNC(dup)
  41 {
  42         printfd(tcp, tcp->u_arg[0]);
  43
  44         return RVAL_DECODED | RVAL_FD;
  45 }
  46
  47 static int
  48 do_dup2(struct tcb *tcp, int flags_arg)
  49 {
  50         printfd(tcp, tcp->u_arg[0]);
  51         tprints(", ");
  52         printfd(tcp, tcp->u_arg[1]);
  53         if (flags_arg >= 0) {
  54                 tprints(", ");
  55                 printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
  56         }
  57
  58         return RVAL_DECODED | RVAL_FD;
  59 }
  60
  61 SYS_FUNC(dup2)
  62 {
  63         return do_dup2(tcp, -1);
  64 }
  65
  66 SYS_FUNC(dup3)
  67 {
  68         return do_dup2(tcp, 2);
  69 }
  70
  71 #if defined(ALPHA)
  72 SYS_FUNC(getdtablesize)
  73 {
  74         return 0;
  75 }
  76 #endif
  77
  78 static int
  79 decode_select(struct tcb *tcp, long *args,
  80               void (*print_tv_ts) (struct tcb *, const long),
  81               const char * (*sprint_tv_ts) (struct tcb *, const long))
  82 {
  83         int i, j;
  84         int nfds, fdsize;
  85         fd_set *fds = NULL;
  86         const char *sep;
  87         long arg;
  88
  89         /* Kernel truncates arg[0] to int, we do the same. */
  90         nfds = (int) args[0];
  91
  92         /* Kernel rejects negative nfds, so we don't parse it either. */
  93         if (nfds < 0)
  94                 nfds = 0;
  95
  96         /* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
  97         if (nfds > 1024*1024)
  98                 nfds = 1024*1024;
  99
 100         /*
 101          * We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
 102          * Instead of args[0], use nfds for fd count, fdsize for array lengths.
 103          */
 104         fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
 105
 106         if (entering(tcp)) {
 107                 tprintf("%d", (int) args[0]);
 108
 109                 if (verbose(tcp) && fdsize > 0)
 110                         fds = malloc(fdsize);
 111                 for (i = 0; i < 3; i++) {
 112                         arg = args[i+1];
 113                         tprints(", ");
 114                         if (!fds) {
 115                                 printaddr(arg);
 116                                 continue;
 117                         }
 118                         if (umoven_or_printaddr(tcp, arg, fdsize, fds))
 119                                 continue;
 120                         tprints("[");
 121                         for (j = 0, sep = "";; j++) {
 122                                 j = next_set_bit(fds, j, nfds);
 123                                 if (j < 0)
 124                                         break;
 125                                 tprints(sep);
 126                                 printfd(tcp, j);
 127                                 sep = " ";
 128                         }
 129                         tprints("]");
 130                 }
 131                 free(fds);
 132                 tprints(", ");
 133                 print_tv_ts(tcp, args[4]);
 134         } else {
 135                 static char outstr[1024];
 136                 char *outptr;
 137 #define end_outstr (outstr + sizeof(outstr))
 138                 int ready_fds;
 139
 140                 if (syserror(tcp))
 141                         return 0;
 142
 143                 ready_fds = tcp->u_rval;
 144                 if (ready_fds == 0) {
 145                         tcp->auxstr = "Timeout";
 146                         return RVAL_STR;
 147                 }
 148
 149                 fds = malloc(fdsize);
 150
 151                 outptr = outstr;
 152                 sep = "";
 153                 for (i = 0; i < 3 && ready_fds > 0; i++) {
 154                         int first = 1;
 155
 156                         arg = args[i+1];
 157                         if (!arg || !fds || umoven(tcp, arg, fdsize, fds) < 0)
 158                                 continue;
 159                         for (j = 0;; j++) {
 160                                 j = next_set_bit(fds, j, nfds);
 161                                 if (j < 0)
 162                                         break;
 163                                 /* +2 chars needed at the end: ']',NUL */
 164                                 if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
 165                                         if (first) {
 166                                                 outptr += sprintf(outptr, "%s%s [%u",
 167                                                         sep,
 168                                                         i == 0 ? "in" : i == 1 ? "out" : "except",
 169                                                         j
 170                                                 );
 171                                                 first = 0;
 172                                                 sep = ", ";
 173                                         }
 174                                         else {
 175                                                 outptr += sprintf(outptr, " %u", j);
 176                                         }
 177                                 }
 178                                 if (--ready_fds == 0)
 179                                         break;
 180                         }
 181                         if (outptr != outstr)
 182                                 *outptr++ = ']';
 183                 }
 184                 free(fds);
 185                 /* This contains no useful information on SunOS.  */
 186                 if (args[4]) {
 187                         const char *str = sprint_tv_ts(tcp, args[4]);
 188                         if (outptr + sizeof("left ") + strlen(sep) + strlen(str) < end_outstr) {
 189                                 outptr += sprintf(outptr, "%sleft %s", sep, str);
 190                         }
 191                 }
 192                 *outptr = '\0';
 193                 tcp->auxstr = outstr;
 194                 return RVAL_STR;
 195 #undef end_outstr
 196         }
 197         return 0;
 198 }
 199
 200 SYS_FUNC(oldselect)
 201 {
 202         long long_args[5];
 203 #undef oldselect_args
 204 #if SIZEOF_LONG == 4
 205 # define oldselect_args long_args
 206 #else
 207         unsigned int oldselect_args[5];
 208         unsigned int i;
 209 #endif
 210
 211         if (umove(tcp, tcp->u_arg[0], &oldselect_args) < 0) {
 212                 printaddr(tcp->u_arg[0]);
 213                 return 0;
 214         }
 215 #ifndef oldselect_args
 216         for (i = 0; i < 5; i++) {
 217                 long_args[i] = oldselect_args[i];
 218         }
 219 #endif
 220         return decode_select(tcp, long_args, print_timeval, sprint_timeval);
 221 #undef oldselect_args
 222 }
 223
 224 #ifdef ALPHA
 225 SYS_FUNC(osf_select)
 226 {
 227         return decode_select(tcp, tcp->u_arg, print_timeval32, sprint_timeval32);
 228 }
 229 #endif
 230
 231 SYS_FUNC(select)
 232 {
 233         return decode_select(tcp, tcp->u_arg, print_timeval, sprint_timeval);
 234 }
 235
 236 #include "kernel_types.h"
 237
 238 static int
 239 umove_kulong_array_or_printaddr(struct tcb *tcp, const long addr,
 240                                 kernel_ulong_t *ptr, size_t n)
 241 {
 242 #if defined X86_64 || defined X32
 243         if (current_personality == 1) {
 244 #else
 245         if (current_wordsize < sizeof(*ptr)) {
 246 #endif
 247                 uint32_t ptr32[n];
 248                 int r = umove_or_printaddr(tcp, addr, &ptr32);
 249                 if (!r) {
 250                         size_t i;
 251
 252                         for (i = 0; i < n; ++i)
 253                                 ptr[i] = (kernel_ulong_t) ptr32[i];
 254                 }
 255                 return r;
 256         }
 257         return umoven_or_printaddr(tcp, addr, n * sizeof(*ptr), ptr);
 258 }
 259
 260 SYS_FUNC(pselect6)
 261 {
 262         int rc = decode_select(tcp, tcp->u_arg, print_timespec, sprint_timespec);
 263         if (entering(tcp)) {
 264                 kernel_ulong_t data[2];
 265
 266                 tprints(", ");
 267                 if (!umove_kulong_array_or_printaddr(tcp, tcp->u_arg[5],
 268                                                      data, ARRAY_SIZE(data))) {
 269                         tprints("{");
 270                         /* NB: kernel requires data[1] == NSIG / 8 */
 271                         print_sigset_addr_len(tcp, (unsigned long) data[0],
 272                                               (unsigned long) data[1]);
 273                         tprintf(", %Lu}", (unsigned long long) data[1]);
 274                 }
 275         }
 276
 277         return rc;
 278 }