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 #include <fcntl.h>
  33 #include <sys/file.h>
  34 #ifdef HAVE_SYS_EPOLL_H
  35 # include <sys/epoll.h>
  36 #endif
  37
  38 #include "xlat/fcntlcmds.h"
  39 #include "xlat/fdflags.h"
  40 #include "xlat/flockcmds.h"
  41 #include "xlat/lockfcmds.h"
  42 #include "xlat/notifyflags.h"
  43
  44 /*
  45  * Assume that F_SETLK64, F_SETLKW64, and F_GETLK64 are either defined
  46  * or not defined altogether.
  47  */
  48 #if defined(F_SETLK64) && F_SETLK64 + 0 != F_SETLK
  49 # define USE_PRINTFLOCK64 1
  50 #else
  51 # define USE_PRINTFLOCK64 0
  52 #endif
  53
  54 #if USE_PRINTFLOCK64
  55
  56 # ifndef HAVE_STRUCT_FLOCK64
  57 struct flock64 {
  58         short int l_type, l_whence;
  59         int64_t l_start, l_len;
  60         int l_pid;
  61 };
  62 # endif
  63
  64 static void
  65 printflock64(struct tcb *tcp, long addr, int getlk)
  66 {
  67         struct flock64 fl;
  68
  69         if (umove_or_printaddr(tcp, addr, &fl))
  70                 return;
  71         tprints("{type=");
  72         printxval(lockfcmds, fl.l_type, "F_???");
  73         tprints(", whence=");
  74         printxval(whence_codes, fl.l_whence, "SEEK_???");
  75         tprintf(", start=%lld, len=%lld", (long long) fl.l_start, (long long) fl.l_len);
  76         if (getlk)
  77                 tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
  78         else
  79                 tprints("}");
  80 }
  81 #endif /* USE_PRINTFLOCK64 */
  82
  83 static void
  84 printflock(struct tcb *tcp, long addr, int getlk)
  85 {
  86         struct flock fl;
  87
  88 #if SUPPORTED_PERSONALITIES > 1
  89         if (
  90 # if SIZEOF_OFF_T > SIZEOF_LONG
  91             current_personality != DEFAULT_PERSONALITY &&
  92 # endif
  93             current_wordsize != sizeof(fl.l_start)) {
  94                 if (current_wordsize == 4) {
  95                         /* 32-bit x86 app on x86_64 and similar cases */
  96                         struct {
  97                                 short int l_type;
  98                                 short int l_whence;
  99                                 int32_t l_start; /* off_t */
 100                                 int32_t l_len; /* off_t */
 101                                 int32_t l_pid; /* pid_t */
 102                         } fl32;
 103                         if (umove_or_printaddr(tcp, addr, &fl32))
 104                                 return;
 105                         fl.l_type = fl32.l_type;
 106                         fl.l_whence = fl32.l_whence;
 107                         fl.l_start = fl32.l_start;
 108                         fl.l_len = fl32.l_len;
 109                         fl.l_pid = fl32.l_pid;
 110                 } else {
 111                         /* let people know we have a problem here */
 112                         tprintf("<decode error: unsupported wordsize %d>",
 113                                 current_wordsize);
 114                         return;
 115                 }
 116         } else
 117 #endif
 118         if (umove_or_printaddr(tcp, addr, &fl))
 119                 return;
 120         tprints("{type=");
 121         printxval(lockfcmds, fl.l_type, "F_???");
 122         tprints(", whence=");
 123         printxval(whence_codes, fl.l_whence, "SEEK_???");
 124 #if SIZEOF_OFF_T > SIZEOF_LONG
 125         tprintf(", start=%lld, len=%lld", fl.l_start, fl.l_len);
 126 #else
 127         tprintf(", start=%ld, len=%ld", fl.l_start, fl.l_len);
 128 #endif
 129         if (getlk)
 130                 tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
 131         else
 132                 tprints("}");
 133 }
 134
 135 SYS_FUNC(fcntl)
 136 {
 137         if (entering(tcp)) {
 138                 printfd(tcp, tcp->u_arg[0]);
 139                 tprints(", ");
 140                 printxval(fcntlcmds, tcp->u_arg[1], "F_???");
 141                 switch (tcp->u_arg[1]) {
 142                 case F_SETFD:
 143                         tprints(", ");
 144                         printflags(fdflags, tcp->u_arg[2], "FD_???");
 145                         break;
 146                 case F_SETOWN: case F_DUPFD:
 147 #ifdef F_DUPFD_CLOEXEC
 148                 case F_DUPFD_CLOEXEC:
 149 #endif
 150                         tprintf(", %ld", tcp->u_arg[2]);
 151                         break;
 152                 case F_SETFL:
 153                         tprints(", ");
 154                         tprint_open_modes(tcp->u_arg[2]);
 155                         break;
 156                 case F_SETLK: case F_SETLKW:
 157                         tprints(", ");
 158                         printflock(tcp, tcp->u_arg[2], 0);
 159                         break;
 160 #if USE_PRINTFLOCK64
 161                 case F_SETLK64: case F_SETLKW64:
 162                         tprints(", ");
 163                         printflock64(tcp, tcp->u_arg[2], 0);
 164                         break;
 165 #endif /* USE_PRINTFLOCK64 */
 166 #ifdef F_NOTIFY
 167                 case F_NOTIFY:
 168                         tprints(", ");
 169                         printflags(notifyflags, tcp->u_arg[2], "DN_???");
 170                         break;
 171 #endif
 172 #ifdef F_SETLEASE
 173                 case F_SETLEASE:
 174                         tprints(", ");
 175                         printxval(lockfcmds, tcp->u_arg[2], "F_???");
 176                         break;
 177 #endif
 178                 }
 179         } else {
 180                 switch (tcp->u_arg[1]) {
 181                 case F_DUPFD:
 182 #ifdef F_DUPFD_CLOEXEC
 183                 case F_DUPFD_CLOEXEC:
 184 #endif
 185                 case F_SETFD: case F_SETFL:
 186                 case F_SETLK: case F_SETLKW:
 187                 case F_SETOWN: case F_GETOWN:
 188 #ifdef F_NOTIFY
 189                 case F_NOTIFY:
 190 #endif
 191 #ifdef F_SETLEASE
 192                 case F_SETLEASE:
 193 #endif
 194                         break;
 195                 case F_GETFD:
 196                         if (syserror(tcp) || tcp->u_rval == 0)
 197                                 return 0;
 198                         tcp->auxstr = sprintflags("flags ", fdflags, tcp->u_rval);
 199                         return RVAL_HEX|RVAL_STR;
 200                 case F_GETFL:
 201                         if (syserror(tcp))
 202                                 return 0;
 203                         tcp->auxstr = sprint_open_modes(tcp->u_rval);
 204                         return RVAL_HEX|RVAL_STR;
 205                 case F_GETLK:
 206                         tprints(", ");
 207                         printflock(tcp, tcp->u_arg[2], 1);
 208                         break;
 209 #if USE_PRINTFLOCK64
 210                 case F_GETLK64:
 211                         tprints(", ");
 212                         printflock64(tcp, tcp->u_arg[2], 1);
 213                         break;
 214 #endif
 215 #ifdef F_GETLEASE
 216                 case F_GETLEASE:
 217                         if (syserror(tcp))
 218                                 return 0;
 219                         tcp->auxstr = xlookup(lockfcmds, tcp->u_rval);
 220                         return RVAL_HEX|RVAL_STR;
 221 #endif
 222                 default:
 223                         tprintf(", %#lx", tcp->u_arg[2]);
 224                         break;
 225                 }
 226         }
 227         return 0;
 228 }
 229
 230 #ifdef LOCK_SH
 231
 232 SYS_FUNC(flock)
 233 {
 234         printfd(tcp, tcp->u_arg[0]);
 235         tprints(", ");
 236         printflags(flockcmds, tcp->u_arg[1], "LOCK_???");
 237
 238         return RVAL_DECODED;
 239 }
 240 #endif /* LOCK_SH */
 241
 242 SYS_FUNC(close)
 243 {
 244         printfd(tcp, tcp->u_arg[0]);
 245
 246         return RVAL_DECODED;
 247 }
 248
 249 SYS_FUNC(dup)
 250 {
 251         printfd(tcp, tcp->u_arg[0]);
 252
 253         return RVAL_DECODED | RVAL_FD;
 254 }
 255
 256 static int
 257 do_dup2(struct tcb *tcp, int flags_arg)
 258 {
 259         printfd(tcp, tcp->u_arg[0]);
 260         tprints(", ");
 261         printfd(tcp, tcp->u_arg[1]);
 262         if (flags_arg >= 0) {
 263                 tprints(", ");
 264                 printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 265         }
 266
 267         return RVAL_DECODED | RVAL_FD;
 268 }
 269
 270 SYS_FUNC(dup2)
 271 {
 272         return do_dup2(tcp, -1);
 273 }
 274
 275 SYS_FUNC(dup3)
 276 {
 277         return do_dup2(tcp, 2);
 278 }
 279
 280 #if defined(ALPHA)
 281 SYS_FUNC(getdtablesize)
 282 {
 283         return 0;
 284 }
 285 #endif
 286
 287 static int
 288 decode_select(struct tcb *tcp, long *args, enum bitness_t bitness)
 289 {
 290         int i, j;
 291         int nfds, fdsize;
 292         fd_set *fds = NULL;
 293         const char *sep;
 294         long arg;
 295
 296         /* Kernel truncates arg[0] to int, we do the same. */
 297         nfds = (int) args[0];
 298
 299         /* Kernel rejects negative nfds, so we don't parse it either. */
 300         if (nfds < 0)
 301                 nfds = 0;
 302
 303         /* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
 304         if (nfds > 1024*1024)
 305                 nfds = 1024*1024;
 306
 307         /*
 308          * We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
 309          * Instead of args[0], use nfds for fd count, fdsize for array lengths.
 310          */
 311         fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
 312
 313         if (entering(tcp)) {
 314                 tprintf("%d", (int) args[0]);
 315
 316                 if (verbose(tcp) && fdsize > 0)
 317                         fds = malloc(fdsize);
 318                 for (i = 0; i < 3; i++) {
 319                         arg = args[i+1];
 320                         tprints(", ");
 321                         if (!fds) {
 322                                 printaddr(arg);
 323                                 continue;
 324                         }
 325                         if (umoven_or_printaddr(tcp, arg, fdsize, fds))
 326                                 continue;
 327                         tprints("[");
 328                         for (j = 0, sep = "";; j++) {
 329                                 j = next_set_bit(fds, j, nfds);
 330                                 if (j < 0)
 331                                         break;
 332                                 tprints(sep);
 333                                 printfd(tcp, j);
 334                                 sep = " ";
 335                         }
 336                         tprints("]");
 337                 }
 338                 free(fds);
 339                 tprints(", ");
 340                 printtv_bitness(tcp, args[4], bitness, 0);
 341         } else {
 342                 static char outstr[1024];
 343                 char *outptr;
 344 #define end_outstr (outstr + sizeof(outstr))
 345                 int ready_fds;
 346
 347                 if (syserror(tcp))
 348                         return 0;
 349
 350                 ready_fds = tcp->u_rval;
 351                 if (ready_fds == 0) {
 352                         tcp->auxstr = "Timeout";
 353                         return RVAL_STR;
 354                 }
 355
 356                 fds = malloc(fdsize);
 357
 358                 outptr = outstr;
 359                 sep = "";
 360                 for (i = 0; i < 3 && ready_fds > 0; i++) {
 361                         int first = 1;
 362
 363                         arg = args[i+1];
 364                         if (!arg || !fds || umoven(tcp, arg, fdsize, fds) < 0)
 365                                 continue;
 366                         for (j = 0;; j++) {
 367                                 j = next_set_bit(fds, j, nfds);
 368                                 if (j < 0)
 369                                         break;
 370                                 /* +2 chars needed at the end: ']',NUL */
 371                                 if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
 372                                         if (first) {
 373                                                 outptr += sprintf(outptr, "%s%s [%u",
 374                                                         sep,
 375                                                         i == 0 ? "in" : i == 1 ? "out" : "except",
 376                                                         j
 377                                                 );
 378                                                 first = 0;
 379                                                 sep = ", ";
 380                                         }
 381                                         else {
 382                                                 outptr += sprintf(outptr, " %u", j);
 383                                         }
 384                                 }
 385                                 if (--ready_fds == 0)
 386                                         break;
 387                         }
 388                         if (outptr != outstr)
 389                                 *outptr++ = ']';
 390                 }
 391                 free(fds);
 392                 /* This contains no useful information on SunOS.  */
 393                 if (args[4]) {
 394                         if (outptr < end_outstr - (10 + TIMEVAL_TEXT_BUFSIZE)) {
 395                                 outptr += sprintf(outptr, "%sleft ", sep);
 396                                 outptr = sprinttv(outptr, tcp, args[4], bitness, /*special:*/ 0);
 397                         }
 398                 }
 399                 *outptr = '\0';
 400                 tcp->auxstr = outstr;
 401                 return RVAL_STR;
 402 #undef end_outstr
 403         }
 404         return 0;
 405 }
 406
 407 SYS_FUNC(oldselect)
 408 {
 409         long long_args[5];
 410 #undef oldselect_args
 411 #if SIZEOF_LONG == 4
 412 # define oldselect_args long_args
 413 #else
 414         unsigned int oldselect_args[5];
 415         unsigned int i;
 416 #endif
 417
 418         if (umove(tcp, tcp->u_arg[0], &oldselect_args) < 0) {
 419                 printaddr(tcp->u_arg[0]);
 420                 return 0;
 421         }
 422 #ifndef oldselect_args
 423         for (i = 0; i < 5; i++) {
 424                 long_args[i] = oldselect_args[i];
 425         }
 426 #endif
 427         return decode_select(tcp, long_args, BITNESS_CURRENT);
 428 #undef oldselect_args
 429 }
 430
 431 #ifdef ALPHA
 432 SYS_FUNC(osf_select)
 433 {
 434         return decode_select(tcp, tcp->u_arg, BITNESS_32);
 435 }
 436 #endif
 437
 438 #include "xlat/epollctls.h"
 439 #include "xlat/epollevents.h"
 440 #include "xlat/epollflags.h"
 441
 442 SYS_FUNC(epoll_create1)
 443 {
 444         printflags(epollflags, tcp->u_arg[0], "EPOLL_???");
 445
 446         return RVAL_DECODED;
 447 }
 448
 449 #ifdef HAVE_SYS_EPOLL_H
 450 static void
 451 print_epoll_event(struct epoll_event *ev)
 452 {
 453         tprints("{");
 454         printflags(epollevents, ev->events, "EPOLL???");
 455         /* We cannot know what format the program uses, so print u32 and u64
 456            which will cover every value.  */
 457         tprintf(", {u32=%" PRIu32 ", u64=%" PRIu64 "}}",
 458                 ev->data.u32, ev->data.u64);
 459 }
 460 #endif
 461
 462 SYS_FUNC(epoll_ctl)
 463 {
 464         struct epoll_event ev;
 465
 466         printfd(tcp, tcp->u_arg[0]);
 467         tprints(", ");
 468         printxval(epollctls, tcp->u_arg[1], "EPOLL_CTL_???");
 469         tprints(", ");
 470         printfd(tcp, tcp->u_arg[2]);
 471         tprints(", ");
 472 #ifdef HAVE_SYS_EPOLL_H
 473         if (EPOLL_CTL_DEL == tcp->u_arg[1])
 474                 printaddr(tcp->u_arg[3]);
 475         else if (!umove_or_printaddr(tcp, tcp->u_arg[3], &ev))
 476                 print_epoll_event(&ev);
 477 #else
 478         printaddr(tcp->u_arg[3]);
 479 #endif
 480
 481         return RVAL_DECODED;
 482 }
 483
 484 static void
 485 print_epoll_event_array(struct tcb *tcp, const long addr, const long len)
 486 {
 487 #ifdef HAVE_SYS_EPOLL_H
 488         struct epoll_event ev, *start, *cur, *end;
 489
 490         if (!len) {
 491                 tprints("[]");
 492                 return;
 493         }
 494
 495         if (umove_or_printaddr(tcp, addr, &ev))
 496                 return;
 497
 498         tprints("[");
 499         print_epoll_event(&ev);
 500
 501         start = (struct epoll_event *) addr;
 502         end = start + len;
 503         for (cur = start + 1; cur < end; ++cur) {
 504                 tprints(", ");
 505                 if (umove_or_printaddr(tcp, (long) cur, &ev))
 506                         break;
 507                 print_epoll_event(&ev);
 508         }
 509         tprints("]");
 510 #else
 511         printaddr(addr);
 512 #endif
 513 }
 514
 515 static void
 516 epoll_wait_common(struct tcb *tcp)
 517 {
 518         if (entering(tcp)) {
 519                 printfd(tcp, tcp->u_arg[0]);
 520                 tprints(", ");
 521         } else {
 522                 print_epoll_event_array(tcp, tcp->u_arg[1], tcp->u_rval);
 523                 tprintf(", %d, %d", (int) tcp->u_arg[2], (int) tcp->u_arg[3]);
 524         }
 525 }
 526
 527 SYS_FUNC(epoll_wait)
 528 {
 529         epoll_wait_common(tcp);
 530         return 0;
 531 }
 532
 533 SYS_FUNC(epoll_pwait)
 534 {
 535         epoll_wait_common(tcp);
 536         if (exiting(tcp)) {
 537                 tprints(", ");
 538                 /* NB: kernel requires arg[5] == NSIG / 8 */
 539                 print_sigset_addr_len(tcp, tcp->u_arg[4], tcp->u_arg[5]);
 540                 tprintf(", %lu", tcp->u_arg[5]);
 541         }
 542         return 0;
 543 }
 544
 545 SYS_FUNC(select)
 546 {
 547         return decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 548 }
 549
 550 SYS_FUNC(pselect6)
 551 {
 552         int rc = decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 553         if (entering(tcp)) {
 554                 long r;
 555                 struct {
 556                         unsigned long ptr;
 557                         unsigned long len;
 558                 } data;
 559
 560                 tprints(", ");
 561 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
 562                 if (current_wordsize == 4) {
 563                         struct {
 564                                 uint32_t ptr;
 565                                 uint32_t len;
 566                         } data32;
 567                         r = umove_or_printaddr(tcp, tcp->u_arg[5], &data32);
 568                         data.ptr = data32.ptr;
 569                         data.len = data32.len;
 570                 } else
 571 #endif
 572                         r = umove_or_printaddr(tcp, tcp->u_arg[5], &data);
 573                 if (r == 0) {
 574                         tprints("{");
 575                         /* NB: kernel requires data.len == NSIG / 8 */
 576                         print_sigset_addr_len(tcp, data.ptr, data.len);
 577                         tprintf(", %lu}", data.len);
 578                 }
 579         }
 580         return rc;
 581 }
 582
 583 static int
 584 do_eventfd(struct tcb *tcp, int flags_arg)
 585 {
 586         tprintf("%lu", tcp->u_arg[0]);
 587         if (flags_arg >= 0) {
 588                 tprints(", ");
 589                 printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 590         }
 591
 592         return RVAL_DECODED;
 593 }
 594
 595 SYS_FUNC(eventfd)
 596 {
 597         return do_eventfd(tcp, -1);
 598 }
 599
 600 SYS_FUNC(eventfd2)
 601 {
 602         return do_eventfd(tcp, 1);
 603 }