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 int
 149 sys_fcntl(struct tcb *tcp)
 150 {
 151         if (entering(tcp)) {
 152                 printfd(tcp, tcp->u_arg[0]);
 153                 tprints(", ");
 154                 printxval(fcntlcmds, tcp->u_arg[1], "F_???");
 155                 switch (tcp->u_arg[1]) {
 156                 case F_SETFD:
 157                         tprints(", ");
 158                         printflags(fdflags, tcp->u_arg[2], "FD_???");
 159                         break;
 160                 case F_SETOWN: case F_DUPFD:
 161 #ifdef F_DUPFD_CLOEXEC
 162                 case F_DUPFD_CLOEXEC:
 163 #endif
 164                         tprintf(", %ld", tcp->u_arg[2]);
 165                         break;
 166                 case F_SETFL:
 167                         tprints(", ");
 168                         tprint_open_modes(tcp->u_arg[2]);
 169                         break;
 170                 case F_SETLK: case F_SETLKW:
 171                         tprints(", ");
 172                         printflock(tcp, tcp->u_arg[2], 0);
 173                         break;
 174 #if USE_PRINTFLOCK64
 175                 case F_SETLK64: case F_SETLKW64:
 176                         tprints(", ");
 177                         printflock64(tcp, tcp->u_arg[2], 0);
 178                         break;
 179 #endif /* USE_PRINTFLOCK64 */
 180 #ifdef F_NOTIFY
 181                 case F_NOTIFY:
 182                         tprints(", ");
 183                         printflags(notifyflags, tcp->u_arg[2], "DN_???");
 184                         break;
 185 #endif
 186 #ifdef F_SETLEASE
 187                 case F_SETLEASE:
 188                         tprints(", ");
 189                         printxval(lockfcmds, tcp->u_arg[2], "F_???");
 190                         break;
 191 #endif
 192                 }
 193         }
 194         else {
 195                 switch (tcp->u_arg[1]) {
 196                 case F_DUPFD:
 197 #ifdef F_DUPFD_CLOEXEC
 198                 case F_DUPFD_CLOEXEC:
 199 #endif
 200                 case F_SETFD: case F_SETFL:
 201                 case F_SETLK: case F_SETLKW:
 202                 case F_SETOWN: case F_GETOWN:
 203 #ifdef F_NOTIFY
 204                 case F_NOTIFY:
 205 #endif
 206 #ifdef F_SETLEASE
 207                 case F_SETLEASE:
 208 #endif
 209                         break;
 210                 case F_GETFD:
 211                         if (syserror(tcp) || tcp->u_rval == 0)
 212                                 return 0;
 213                         tcp->auxstr = sprintflags("flags ", fdflags, tcp->u_rval);
 214                         return RVAL_HEX|RVAL_STR;
 215                 case F_GETFL:
 216                         if (syserror(tcp))
 217                                 return 0;
 218                         tcp->auxstr = sprint_open_modes(tcp->u_rval);
 219                         return RVAL_HEX|RVAL_STR;
 220                 case F_GETLK:
 221                         tprints(", ");
 222                         printflock(tcp, tcp->u_arg[2], 1);
 223                         break;
 224 #if USE_PRINTFLOCK64
 225                 case F_GETLK64:
 226                         tprints(", ");
 227                         printflock64(tcp, tcp->u_arg[2], 1);
 228                         break;
 229 #endif
 230 #ifdef F_GETLEASE
 231                 case F_GETLEASE:
 232                         if (syserror(tcp))
 233                                 return 0;
 234                         tcp->auxstr = xlookup(lockfcmds, tcp->u_rval);
 235                         return RVAL_HEX|RVAL_STR;
 236 #endif
 237                 default:
 238                         tprintf(", %#lx", tcp->u_arg[2]);
 239                         break;
 240                 }
 241         }
 242         return 0;
 243 }
 244
 245 #ifdef LOCK_SH
 246
 247 int
 248 sys_flock(struct tcb *tcp)
 249 {
 250         if (entering(tcp)) {
 251                 printfd(tcp, tcp->u_arg[0]);
 252                 tprints(", ");
 253                 printflags(flockcmds, tcp->u_arg[1], "LOCK_???");
 254         }
 255         return 0;
 256 }
 257 #endif /* LOCK_SH */
 258
 259 int
 260 sys_close(struct tcb *tcp)
 261 {
 262         if (entering(tcp)) {
 263                 printfd(tcp, tcp->u_arg[0]);
 264         }
 265         return 0;
 266 }
 267
 268 int
 269 sys_dup(struct tcb *tcp)
 270 {
 271         if (entering(tcp)) {
 272                 printfd(tcp, tcp->u_arg[0]);
 273         }
 274         return RVAL_FD;
 275 }
 276
 277 static int
 278 do_dup2(struct tcb *tcp, int flags_arg)
 279 {
 280         if (entering(tcp)) {
 281                 printfd(tcp, tcp->u_arg[0]);
 282                 tprints(", ");
 283                 printfd(tcp, tcp->u_arg[1]);
 284                 if (flags_arg >= 0) {
 285                         tprints(", ");
 286                         printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 287                 }
 288         }
 289         return RVAL_FD;
 290 }
 291
 292 int
 293 sys_dup2(struct tcb *tcp)
 294 {
 295         return do_dup2(tcp, -1);
 296 }
 297
 298 int
 299 sys_dup3(struct tcb *tcp)
 300 {
 301         return do_dup2(tcp, 2);
 302 }
 303
 304 #if defined(ALPHA)
 305 int
 306 sys_getdtablesize(struct tcb *tcp)
 307 {
 308         return 0;
 309 }
 310 #endif
 311
 312 static int
 313 decode_select(struct tcb *tcp, long *args, enum bitness_t bitness)
 314 {
 315         int i, j;
 316         int nfds, fdsize;
 317         fd_set *fds = NULL;
 318         const char *sep;
 319         long arg;
 320
 321         /* Kernel truncates arg[0] to int, we do the same. */
 322         nfds = (int) args[0];
 323
 324         /* Kernel rejects negative nfds, so we don't parse it either. */
 325         if (nfds < 0)
 326                 nfds = 0;
 327
 328         /* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
 329         if (nfds > 1024*1024)
 330                 nfds = 1024*1024;
 331
 332         /*
 333          * We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
 334          * Instead of args[0], use nfds for fd count, fdsize for array lengths.
 335          */
 336         fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
 337
 338         if (entering(tcp)) {
 339                 tprintf("%d", (int) args[0]);
 340
 341                 if (fdsize > 0) {
 342                         fds = malloc(fdsize);
 343                         if (!fds)
 344                                 die_out_of_memory();
 345                 }
 346                 for (i = 0; i < 3; i++) {
 347                         arg = args[i+1];
 348                         if (arg == 0) {
 349                                 tprints(", NULL");
 350                                 continue;
 351                         }
 352                         if (!verbose(tcp) || !fds) {
 353                                 tprintf(", %#lx", arg);
 354                                 continue;
 355                         }
 356                         if (umoven(tcp, arg, fdsize, (char *) fds) < 0) {
 357                                 tprints(", [?]");
 358                                 continue;
 359                         }
 360                         tprints(", [");
 361                         for (j = 0, sep = "";; j++) {
 362                                 j = next_set_bit(fds, j, nfds);
 363                                 if (j < 0)
 364                                         break;
 365                                 tprints(sep);
 366                                 printfd(tcp, j);
 367                                 sep = " ";
 368                         }
 369                         tprints("]");
 370                 }
 371                 free(fds);
 372                 tprints(", ");
 373                 printtv_bitness(tcp, args[4], bitness, 0);
 374         }
 375         else {
 376                 static char outstr[1024];
 377                 char *outptr;
 378 #define end_outstr (outstr + sizeof(outstr))
 379                 int ready_fds;
 380
 381                 if (syserror(tcp))
 382                         return 0;
 383
 384                 ready_fds = tcp->u_rval;
 385                 if (ready_fds == 0) {
 386                         tcp->auxstr = "Timeout";
 387                         return RVAL_STR;
 388                 }
 389
 390                 fds = malloc(fdsize);
 391                 if (!fds)
 392                         die_out_of_memory();
 393
 394                 outptr = outstr;
 395                 sep = "";
 396                 for (i = 0; i < 3 && ready_fds > 0; i++) {
 397                         int first = 1;
 398
 399                         arg = args[i+1];
 400                         if (!arg || umoven(tcp, arg, fdsize, (char *) fds) < 0)
 401                                 continue;
 402                         for (j = 0;; j++) {
 403                                 j = next_set_bit(fds, j, nfds);
 404                                 if (j < 0)
 405                                         break;
 406                                 /* +2 chars needed at the end: ']',NUL */
 407                                 if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
 408                                         if (first) {
 409                                                 outptr += sprintf(outptr, "%s%s [%u",
 410                                                         sep,
 411                                                         i == 0 ? "in" : i == 1 ? "out" : "except",
 412                                                         j
 413                                                 );
 414                                                 first = 0;
 415                                                 sep = ", ";
 416                                         }
 417                                         else {
 418                                                 outptr += sprintf(outptr, " %u", j);
 419                                         }
 420                                 }
 421                                 if (--ready_fds == 0)
 422                                         break;
 423                         }
 424                         if (outptr != outstr)
 425                                 *outptr++ = ']';
 426                 }
 427                 free(fds);
 428                 /* This contains no useful information on SunOS.  */
 429                 if (args[4]) {
 430                         if (outptr < end_outstr - (10 + TIMEVAL_TEXT_BUFSIZE)) {
 431                                 outptr += sprintf(outptr, "%sleft ", sep);
 432                                 outptr = sprinttv(outptr, tcp, args[4], bitness, /*special:*/ 0);
 433                         }
 434                 }
 435                 *outptr = '\0';
 436                 tcp->auxstr = outstr;
 437                 return RVAL_STR;
 438 #undef end_outstr
 439         }
 440         return 0;
 441 }
 442
 443 int
 444 sys_oldselect(struct tcb *tcp)
 445 {
 446         long args[5];
 447
 448         if (umoven(tcp, tcp->u_arg[0], sizeof args, (char *) args) < 0) {
 449                 tprints("[...]");
 450                 return 0;
 451         }
 452         return decode_select(tcp, args, BITNESS_CURRENT);
 453 }
 454
 455 #ifdef ALPHA
 456 int
 457 sys_osf_select(struct tcb *tcp)
 458 {
 459         long *args = tcp->u_arg;
 460         return decode_select(tcp, args, BITNESS_32);
 461 }
 462 #endif
 463
 464 #include "xlat/epollctls.h"
 465 #include "xlat/epollevents.h"
 466 #include "xlat/epollflags.h"
 467
 468 /* Not aliased to printargs_ld: we want it to have a distinct address */
 469 int
 470 sys_epoll_create(struct tcb *tcp)
 471 {
 472         return printargs_ld(tcp);
 473 }
 474
 475 int
 476 sys_epoll_create1(struct tcb *tcp)
 477 {
 478         if (entering(tcp))
 479                 printflags(epollflags, tcp->u_arg[0], "EPOLL_???");
 480         return 0;
 481 }
 482
 483 #ifdef HAVE_SYS_EPOLL_H
 484 static void
 485 print_epoll_event(struct epoll_event *ev)
 486 {
 487         tprints("{");
 488         printflags(epollevents, ev->events, "EPOLL???");
 489         /* We cannot know what format the program uses, so print u32 and u64
 490            which will cover every value.  */
 491         tprintf(", {u32=%" PRIu32 ", u64=%" PRIu64 "}}",
 492                 ev->data.u32, ev->data.u64);
 493 }
 494 #endif
 495
 496 int
 497 sys_epoll_ctl(struct tcb *tcp)
 498 {
 499         if (entering(tcp)) {
 500                 printfd(tcp, tcp->u_arg[0]);
 501                 tprints(", ");
 502                 printxval(epollctls, tcp->u_arg[1], "EPOLL_CTL_???");
 503                 tprints(", ");
 504                 printfd(tcp, tcp->u_arg[2]);
 505                 tprints(", ");
 506                 if (tcp->u_arg[3] == 0)
 507                         tprints("NULL");
 508                 else {
 509 #ifdef HAVE_SYS_EPOLL_H
 510                         struct epoll_event ev;
 511                         if (
 512 #ifdef EPOLL_CTL_DEL
 513                             (tcp->u_arg[1] != EPOLL_CTL_DEL) &&
 514 #endif
 515                             umove(tcp, tcp->u_arg[3], &ev) == 0)
 516                                 print_epoll_event(&ev);
 517                         else
 518 #endif
 519                                 tprintf("%lx", tcp->u_arg[3]);
 520                 }
 521         }
 522         return 0;
 523 }
 524
 525 static void
 526 epoll_wait_common(struct tcb *tcp)
 527 {
 528         if (entering(tcp)) {
 529                 printfd(tcp, tcp->u_arg[0]);
 530                 tprints(", ");
 531         } else {
 532                 if (syserror(tcp))
 533                         tprintf("%lx", tcp->u_arg[1]);
 534                 else if (tcp->u_rval == 0)
 535                         tprints("{}");
 536                 else {
 537 #ifdef HAVE_SYS_EPOLL_H
 538                         struct epoll_event ev, *start, *cur, *end;
 539                         int failed = 0;
 540
 541                         tprints("{");
 542                         start = (struct epoll_event *) tcp->u_arg[1];
 543                         end = start + tcp->u_rval;
 544                         for (cur = start; cur < end; ++cur) {
 545                                 if (cur > start)
 546                                         tprints(", ");
 547                                 if (umove(tcp, (long) cur, &ev) == 0)
 548                                         print_epoll_event(&ev);
 549                                 else {
 550                                         tprints("?");
 551                                         failed = 1;
 552                                         break;
 553                                 }
 554                         }
 555                         tprints("}");
 556                         if (failed)
 557                                 tprintf(" %#lx", (long) start);
 558 #else
 559                         tprints("{...}");
 560 #endif
 561                 }
 562                 tprintf(", %d, %d", (int) tcp->u_arg[2], (int) tcp->u_arg[3]);
 563         }
 564 }
 565
 566 int
 567 sys_epoll_wait(struct tcb *tcp)
 568 {
 569         epoll_wait_common(tcp);
 570         return 0;
 571 }
 572
 573 int
 574 sys_epoll_pwait(struct tcb *tcp)
 575 {
 576         epoll_wait_common(tcp);
 577         if (exiting(tcp)) {
 578                 tprints(", ");
 579                 /* NB: kernel requires arg[5] == NSIG / 8 */
 580                 print_sigset_addr_len(tcp, tcp->u_arg[4], tcp->u_arg[5]);
 581                 tprintf(", %lu", tcp->u_arg[5]);
 582         }
 583         return 0;
 584 }
 585
 586 int
 587 sys_select(struct tcb *tcp)
 588 {
 589         return decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 590 }
 591
 592 int
 593 sys_pselect6(struct tcb *tcp)
 594 {
 595         int rc = decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 596         if (entering(tcp)) {
 597                 long r;
 598                 struct {
 599                         unsigned long ptr;
 600                         unsigned long len;
 601                 } data;
 602 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
 603                 if (current_wordsize == 4) {
 604                         struct {
 605                                 uint32_t ptr;
 606                                 uint32_t len;
 607                         } data32;
 608                         r = umove(tcp, tcp->u_arg[5], &data32);
 609                         data.ptr = data32.ptr;
 610                         data.len = data32.len;
 611                 } else
 612 #endif
 613                         r = umove(tcp, tcp->u_arg[5], &data);
 614                 if (r < 0)
 615                         tprintf(", %#lx", tcp->u_arg[5]);
 616                 else {
 617                         tprints(", {");
 618                         /* NB: kernel requires data.len == NSIG / 8 */
 619                         print_sigset_addr_len(tcp, data.ptr, data.len);
 620                         tprintf(", %lu}", data.len);
 621                 }
 622         }
 623         return rc;
 624 }
 625
 626 static int
 627 do_eventfd(struct tcb *tcp, int flags_arg)
 628 {
 629         if (entering(tcp)) {
 630                 tprintf("%lu", tcp->u_arg[0]);
 631                 if (flags_arg >= 0) {
 632                         tprints(", ");
 633                         printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 634                 }
 635         }
 636         return 0;
 637 }
 638
 639 int
 640 sys_eventfd(struct tcb *tcp)
 641 {
 642         return do_eventfd(tcp, -1);
 643 }
 644
 645 int
 646 sys_eventfd2(struct tcb *tcp)
 647 {
 648         return do_eventfd(tcp, 1);
 649 }
 650
 651 int
 652 sys_perf_event_open(struct tcb *tcp)
 653 {
 654         if (entering(tcp)) {
 655                 tprintf("%#lx, %d, %d, %d, ",
 656                         tcp->u_arg[0],
 657                         (int) tcp->u_arg[1],
 658                         (int) tcp->u_arg[2],
 659                         (int) tcp->u_arg[3]);
 660                 printflags(perf_event_open_flags, tcp->u_arg[4],
 661                            "PERF_FLAG_???");
 662         }
 663         return 0;
 664 }