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 #ifdef HAVE_LINUX_PERF_EVENT_H
  38 # include  <linux/perf_event.h>
  39 #endif
  40
  41 #include "xlat/fcntlcmds.h"
  42 #include "xlat/fdflags.h"
  43 #include "xlat/flockcmds.h"
  44 #include "xlat/lockfcmds.h"
  45 #include "xlat/notifyflags.h"
  46 #include "xlat/perf_event_open_flags.h"
  47
  48 /*
  49  * Assume that F_SETLK64, F_SETLKW64, and F_GETLK64 are either defined
  50  * or not defined altogether.
  51  */
  52 #if defined(F_SETLK64) && F_SETLK64 + 0 != F_SETLK
  53 # define USE_PRINTFLOCK64 1
  54 #else
  55 # define USE_PRINTFLOCK64 0
  56 #endif
  57
  58 #if USE_PRINTFLOCK64
  59
  60 # ifndef HAVE_STRUCT_FLOCK64
  61 struct flock64 {
  62         short int l_type, l_whence;
  63         int64_t l_start, l_len;
  64         int l_pid;
  65 };
  66 # endif
  67
  68 static void
  69 printflock64(struct tcb *tcp, long addr, int getlk)
  70 {
  71         struct flock64 fl;
  72
  73         if (umove(tcp, addr, &fl) < 0) {
  74                 tprints("{...}");
  75                 return;
  76         }
  77         tprints("{type=");
  78         printxval(lockfcmds, fl.l_type, "F_???");
  79         tprints(", whence=");
  80         printxval(whence_codes, fl.l_whence, "SEEK_???");
  81         tprintf(", start=%lld, len=%lld", (long long) fl.l_start, (long long) fl.l_len);
  82         if (getlk)
  83                 tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
  84         else
  85                 tprints("}");
  86 }
  87 #endif /* USE_PRINTFLOCK64 */
  88
  89 static void
  90 printflock(struct tcb *tcp, long addr, int getlk)
  91 {
  92         struct flock fl;
  93         int r;
  94
  95 #if SUPPORTED_PERSONALITIES > 1
  96         if (
  97 # if SIZEOF_OFF_T > SIZEOF_LONG
  98             current_personality > 0 &&
  99 #endif
 100             current_wordsize != sizeof(fl.l_start)) {
 101                 if (current_wordsize == 4) {
 102                         /* 32-bit x86 app on x86_64 and similar cases */
 103                         struct {
 104                                 short int l_type;
 105                                 short int l_whence;
 106                                 int32_t l_start; /* off_t */
 107                                 int32_t l_len; /* off_t */
 108                                 int32_t l_pid; /* pid_t */
 109                         } fl32;
 110                         r = umove(tcp, addr, &fl32);
 111                         if (r >= 0) {
 112                                 fl.l_type = fl32.l_type;
 113                                 fl.l_whence = fl32.l_whence;
 114                                 fl.l_start = fl32.l_start;
 115                                 fl.l_len = fl32.l_len;
 116                                 fl.l_pid = fl32.l_pid;
 117                         }
 118                 } else {
 119                         /* let people know we have a problem here */
 120                         tprintf("<decode error: unsupported wordsize %d>",
 121                                 current_wordsize);
 122                         return;
 123                 }
 124         } else
 125 #endif
 126         {
 127                 r = umove(tcp, addr, &fl);
 128         }
 129         if (r < 0) {
 130                 tprints("{...}");
 131                 return;
 132         }
 133         tprints("{type=");
 134         printxval(lockfcmds, fl.l_type, "F_???");
 135         tprints(", whence=");
 136         printxval(whence_codes, fl.l_whence, "SEEK_???");
 137 #if SIZEOF_OFF_T > SIZEOF_LONG
 138         tprintf(", start=%lld, len=%lld", fl.l_start, fl.l_len);
 139 #else
 140         tprintf(", start=%ld, len=%ld", fl.l_start, fl.l_len);
 141 #endif
 142         if (getlk)
 143                 tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
 144         else
 145                 tprints("}");
 146 }
 147
 148 SYS_FUNC(fcntl)
 149 {
 150         if (entering(tcp)) {
 151                 printfd(tcp, tcp->u_arg[0]);
 152                 tprints(", ");
 153                 printxval(fcntlcmds, tcp->u_arg[1], "F_???");
 154                 switch (tcp->u_arg[1]) {
 155                 case F_SETFD:
 156                         tprints(", ");
 157                         printflags(fdflags, tcp->u_arg[2], "FD_???");
 158                         break;
 159                 case F_SETOWN: case F_DUPFD:
 160 #ifdef F_DUPFD_CLOEXEC
 161                 case F_DUPFD_CLOEXEC:
 162 #endif
 163                         tprintf(", %ld", tcp->u_arg[2]);
 164                         break;
 165                 case F_SETFL:
 166                         tprints(", ");
 167                         tprint_open_modes(tcp->u_arg[2]);
 168                         break;
 169                 case F_SETLK: case F_SETLKW:
 170                         tprints(", ");
 171                         printflock(tcp, tcp->u_arg[2], 0);
 172                         break;
 173 #if USE_PRINTFLOCK64
 174                 case F_SETLK64: case F_SETLKW64:
 175                         tprints(", ");
 176                         printflock64(tcp, tcp->u_arg[2], 0);
 177                         break;
 178 #endif /* USE_PRINTFLOCK64 */
 179 #ifdef F_NOTIFY
 180                 case F_NOTIFY:
 181                         tprints(", ");
 182                         printflags(notifyflags, tcp->u_arg[2], "DN_???");
 183                         break;
 184 #endif
 185 #ifdef F_SETLEASE
 186                 case F_SETLEASE:
 187                         tprints(", ");
 188                         printxval(lockfcmds, tcp->u_arg[2], "F_???");
 189                         break;
 190 #endif
 191                 }
 192         }
 193         else {
 194                 switch (tcp->u_arg[1]) {
 195                 case F_DUPFD:
 196 #ifdef F_DUPFD_CLOEXEC
 197                 case F_DUPFD_CLOEXEC:
 198 #endif
 199                 case F_SETFD: case F_SETFL:
 200                 case F_SETLK: case F_SETLKW:
 201                 case F_SETOWN: case F_GETOWN:
 202 #ifdef F_NOTIFY
 203                 case F_NOTIFY:
 204 #endif
 205 #ifdef F_SETLEASE
 206                 case F_SETLEASE:
 207 #endif
 208                         break;
 209                 case F_GETFD:
 210                         if (syserror(tcp) || tcp->u_rval == 0)
 211                                 return 0;
 212                         tcp->auxstr = sprintflags("flags ", fdflags, tcp->u_rval);
 213                         return RVAL_HEX|RVAL_STR;
 214                 case F_GETFL:
 215                         if (syserror(tcp))
 216                                 return 0;
 217                         tcp->auxstr = sprint_open_modes(tcp->u_rval);
 218                         return RVAL_HEX|RVAL_STR;
 219                 case F_GETLK:
 220                         tprints(", ");
 221                         printflock(tcp, tcp->u_arg[2], 1);
 222                         break;
 223 #if USE_PRINTFLOCK64
 224                 case F_GETLK64:
 225                         tprints(", ");
 226                         printflock64(tcp, tcp->u_arg[2], 1);
 227                         break;
 228 #endif
 229 #ifdef F_GETLEASE
 230                 case F_GETLEASE:
 231                         if (syserror(tcp))
 232                                 return 0;
 233                         tcp->auxstr = xlookup(lockfcmds, tcp->u_rval);
 234                         return RVAL_HEX|RVAL_STR;
 235 #endif
 236                 default:
 237                         tprintf(", %#lx", tcp->u_arg[2]);
 238                         break;
 239                 }
 240         }
 241         return 0;
 242 }
 243
 244 #ifdef LOCK_SH
 245
 246 SYS_FUNC(flock)
 247 {
 248         if (entering(tcp)) {
 249                 printfd(tcp, tcp->u_arg[0]);
 250                 tprints(", ");
 251                 printflags(flockcmds, tcp->u_arg[1], "LOCK_???");
 252         }
 253         return 0;
 254 }
 255 #endif /* LOCK_SH */
 256
 257 SYS_FUNC(close)
 258 {
 259         if (entering(tcp)) {
 260                 printfd(tcp, tcp->u_arg[0]);
 261         }
 262         return 0;
 263 }
 264
 265 SYS_FUNC(dup)
 266 {
 267         if (entering(tcp)) {
 268                 printfd(tcp, tcp->u_arg[0]);
 269         }
 270         return RVAL_FD;
 271 }
 272
 273 static int
 274 do_dup2(struct tcb *tcp, int flags_arg)
 275 {
 276         if (entering(tcp)) {
 277                 printfd(tcp, tcp->u_arg[0]);
 278                 tprints(", ");
 279                 printfd(tcp, tcp->u_arg[1]);
 280                 if (flags_arg >= 0) {
 281                         tprints(", ");
 282                         printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 283                 }
 284         }
 285         return RVAL_FD;
 286 }
 287
 288 SYS_FUNC(dup2)
 289 {
 290         return do_dup2(tcp, -1);
 291 }
 292
 293 SYS_FUNC(dup3)
 294 {
 295         return do_dup2(tcp, 2);
 296 }
 297
 298 #if defined(ALPHA)
 299 SYS_FUNC(getdtablesize)
 300 {
 301         return 0;
 302 }
 303 #endif
 304
 305 static int
 306 decode_select(struct tcb *tcp, long *args, enum bitness_t bitness)
 307 {
 308         int i, j;
 309         int nfds, fdsize;
 310         fd_set *fds = NULL;
 311         const char *sep;
 312         long arg;
 313
 314         /* Kernel truncates arg[0] to int, we do the same. */
 315         nfds = (int) args[0];
 316
 317         /* Kernel rejects negative nfds, so we don't parse it either. */
 318         if (nfds < 0)
 319                 nfds = 0;
 320
 321         /* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
 322         if (nfds > 1024*1024)
 323                 nfds = 1024*1024;
 324
 325         /*
 326          * We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
 327          * Instead of args[0], use nfds for fd count, fdsize for array lengths.
 328          */
 329         fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
 330
 331         if (entering(tcp)) {
 332                 tprintf("%d", (int) args[0]);
 333
 334                 if (verbose(tcp) && fdsize > 0)
 335                         fds = xmalloc(fdsize);
 336                 for (i = 0; i < 3; i++) {
 337                         arg = args[i+1];
 338                         if (arg == 0) {
 339                                 tprints(", NULL");
 340                                 continue;
 341                         }
 342                         if (!fds) {
 343                                 tprintf(", %#lx", arg);
 344                                 continue;
 345                         }
 346                         if (umoven(tcp, arg, fdsize, fds) < 0) {
 347                                 tprints(", [?]");
 348                                 continue;
 349                         }
 350                         tprints(", [");
 351                         for (j = 0, sep = "";; j++) {
 352                                 j = next_set_bit(fds, j, nfds);
 353                                 if (j < 0)
 354                                         break;
 355                                 tprints(sep);
 356                                 printfd(tcp, j);
 357                                 sep = " ";
 358                         }
 359                         tprints("]");
 360                 }
 361                 free(fds);
 362                 tprints(", ");
 363                 printtv_bitness(tcp, args[4], bitness, 0);
 364         }
 365         else {
 366                 static char outstr[1024];
 367                 char *outptr;
 368 #define end_outstr (outstr + sizeof(outstr))
 369                 int ready_fds;
 370
 371                 if (syserror(tcp))
 372                         return 0;
 373
 374                 ready_fds = tcp->u_rval;
 375                 if (ready_fds == 0) {
 376                         tcp->auxstr = "Timeout";
 377                         return RVAL_STR;
 378                 }
 379
 380                 fds = xmalloc(fdsize);
 381
 382                 outptr = outstr;
 383                 sep = "";
 384                 for (i = 0; i < 3 && ready_fds > 0; i++) {
 385                         int first = 1;
 386
 387                         arg = args[i+1];
 388                         if (!arg || umoven(tcp, arg, fdsize, fds) < 0)
 389                                 continue;
 390                         for (j = 0;; j++) {
 391                                 j = next_set_bit(fds, j, nfds);
 392                                 if (j < 0)
 393                                         break;
 394                                 /* +2 chars needed at the end: ']',NUL */
 395                                 if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
 396                                         if (first) {
 397                                                 outptr += sprintf(outptr, "%s%s [%u",
 398                                                         sep,
 399                                                         i == 0 ? "in" : i == 1 ? "out" : "except",
 400                                                         j
 401                                                 );
 402                                                 first = 0;
 403                                                 sep = ", ";
 404                                         }
 405                                         else {
 406                                                 outptr += sprintf(outptr, " %u", j);
 407                                         }
 408                                 }
 409                                 if (--ready_fds == 0)
 410                                         break;
 411                         }
 412                         if (outptr != outstr)
 413                                 *outptr++ = ']';
 414                 }
 415                 free(fds);
 416                 /* This contains no useful information on SunOS.  */
 417                 if (args[4]) {
 418                         if (outptr < end_outstr - (10 + TIMEVAL_TEXT_BUFSIZE)) {
 419                                 outptr += sprintf(outptr, "%sleft ", sep);
 420                                 outptr = sprinttv(outptr, tcp, args[4], bitness, /*special:*/ 0);
 421                         }
 422                 }
 423                 *outptr = '\0';
 424                 tcp->auxstr = outstr;
 425                 return RVAL_STR;
 426 #undef end_outstr
 427         }
 428         return 0;
 429 }
 430
 431 SYS_FUNC(oldselect)
 432 {
 433         long args[5];
 434
 435         if (umoven(tcp, tcp->u_arg[0], sizeof args, args) < 0) {
 436                 tprints("[...]");
 437                 return 0;
 438         }
 439         return decode_select(tcp, args, BITNESS_CURRENT);
 440 }
 441
 442 #ifdef ALPHA
 443 SYS_FUNC(osf_select)
 444 {
 445         long *args = tcp->u_arg;
 446         return decode_select(tcp, args, BITNESS_32);
 447 }
 448 #endif
 449
 450 #include "xlat/epollctls.h"
 451 #include "xlat/epollevents.h"
 452 #include "xlat/epollflags.h"
 453
 454 /* Not aliased to printargs_ld: we want it to have a distinct address */
 455 SYS_FUNC(epoll_create)
 456 {
 457         return printargs_ld(tcp);
 458 }
 459
 460 SYS_FUNC(epoll_create1)
 461 {
 462         if (entering(tcp))
 463                 printflags(epollflags, tcp->u_arg[0], "EPOLL_???");
 464         return 0;
 465 }
 466
 467 #ifdef HAVE_SYS_EPOLL_H
 468 static void
 469 print_epoll_event(struct epoll_event *ev)
 470 {
 471         tprints("{");
 472         printflags(epollevents, ev->events, "EPOLL???");
 473         /* We cannot know what format the program uses, so print u32 and u64
 474            which will cover every value.  */
 475         tprintf(", {u32=%" PRIu32 ", u64=%" PRIu64 "}}",
 476                 ev->data.u32, ev->data.u64);
 477 }
 478 #endif
 479
 480 SYS_FUNC(epoll_ctl)
 481 {
 482         if (entering(tcp)) {
 483                 printfd(tcp, tcp->u_arg[0]);
 484                 tprints(", ");
 485                 printxval(epollctls, tcp->u_arg[1], "EPOLL_CTL_???");
 486                 tprints(", ");
 487                 printfd(tcp, tcp->u_arg[2]);
 488                 tprints(", ");
 489                 if (tcp->u_arg[3] == 0)
 490                         tprints("NULL");
 491                 else {
 492 #ifdef HAVE_SYS_EPOLL_H
 493                         struct epoll_event ev;
 494                         if (
 495 #ifdef EPOLL_CTL_DEL
 496                             (tcp->u_arg[1] != EPOLL_CTL_DEL) &&
 497 #endif
 498                             umove(tcp, tcp->u_arg[3], &ev) == 0)
 499                                 print_epoll_event(&ev);
 500                         else
 501 #endif
 502                                 tprintf("%lx", tcp->u_arg[3]);
 503                 }
 504         }
 505         return 0;
 506 }
 507
 508 static void
 509 epoll_wait_common(struct tcb *tcp)
 510 {
 511         if (entering(tcp)) {
 512                 printfd(tcp, tcp->u_arg[0]);
 513                 tprints(", ");
 514         } else {
 515                 if (syserror(tcp))
 516                         tprintf("%lx", tcp->u_arg[1]);
 517                 else if (tcp->u_rval == 0)
 518                         tprints("{}");
 519                 else {
 520 #ifdef HAVE_SYS_EPOLL_H
 521                         struct epoll_event ev, *start, *cur, *end;
 522                         int failed = 0;
 523
 524                         tprints("{");
 525                         start = (struct epoll_event *) tcp->u_arg[1];
 526                         end = start + tcp->u_rval;
 527                         for (cur = start; cur < end; ++cur) {
 528                                 if (cur > start)
 529                                         tprints(", ");
 530                                 if (umove(tcp, (long) cur, &ev) == 0)
 531                                         print_epoll_event(&ev);
 532                                 else {
 533                                         tprints("?");
 534                                         failed = 1;
 535                                         break;
 536                                 }
 537                         }
 538                         tprints("}");
 539                         if (failed)
 540                                 tprintf(" %#lx", (long) start);
 541 #else
 542                         tprints("{...}");
 543 #endif
 544                 }
 545                 tprintf(", %d, %d", (int) tcp->u_arg[2], (int) tcp->u_arg[3]);
 546         }
 547 }
 548
 549 SYS_FUNC(epoll_wait)
 550 {
 551         epoll_wait_common(tcp);
 552         return 0;
 553 }
 554
 555 SYS_FUNC(epoll_pwait)
 556 {
 557         epoll_wait_common(tcp);
 558         if (exiting(tcp)) {
 559                 tprints(", ");
 560                 /* NB: kernel requires arg[5] == NSIG / 8 */
 561                 print_sigset_addr_len(tcp, tcp->u_arg[4], tcp->u_arg[5]);
 562                 tprintf(", %lu", tcp->u_arg[5]);
 563         }
 564         return 0;
 565 }
 566
 567 SYS_FUNC(select)
 568 {
 569         return decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 570 }
 571
 572 SYS_FUNC(pselect6)
 573 {
 574         int rc = decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 575         if (entering(tcp)) {
 576                 long r;
 577                 struct {
 578                         unsigned long ptr;
 579                         unsigned long len;
 580                 } data;
 581 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
 582                 if (current_wordsize == 4) {
 583                         struct {
 584                                 uint32_t ptr;
 585                                 uint32_t len;
 586                         } data32;
 587                         r = umove(tcp, tcp->u_arg[5], &data32);
 588                         data.ptr = data32.ptr;
 589                         data.len = data32.len;
 590                 } else
 591 #endif
 592                         r = umove(tcp, tcp->u_arg[5], &data);
 593                 if (r < 0)
 594                         tprintf(", %#lx", tcp->u_arg[5]);
 595                 else {
 596                         tprints(", {");
 597                         /* NB: kernel requires data.len == NSIG / 8 */
 598                         print_sigset_addr_len(tcp, data.ptr, data.len);
 599                         tprintf(", %lu}", data.len);
 600                 }
 601         }
 602         return rc;
 603 }
 604
 605 static int
 606 do_eventfd(struct tcb *tcp, int flags_arg)
 607 {
 608         if (entering(tcp)) {
 609                 tprintf("%lu", tcp->u_arg[0]);
 610                 if (flags_arg >= 0) {
 611                         tprints(", ");
 612                         printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 613                 }
 614         }
 615         return 0;
 616 }
 617
 618 SYS_FUNC(eventfd)
 619 {
 620         return do_eventfd(tcp, -1);
 621 }
 622
 623 SYS_FUNC(eventfd2)
 624 {
 625         return do_eventfd(tcp, 1);
 626 }
 627
 628 SYS_FUNC(perf_event_open)
 629 {
 630         if (entering(tcp)) {
 631                 tprintf("%#lx, %d, %d, %d, ",
 632                         tcp->u_arg[0],
 633                         (int) tcp->u_arg[1],
 634                         (int) tcp->u_arg[2],
 635                         (int) tcp->u_arg[3]);
 636                 printflags(perf_event_open_flags, tcp->u_arg[4],
 637                            "PERF_FLAG_???");
 638         }
 639         return 0;
 640 }