granicus.if.org Git - strace/blob - syscall.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  * Copyright (c) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
   7  *                     Linux for s390 port by D.J. Barrow
   8  *                    <barrow_dj@mail.yahoo.com,djbarrow@de.ibm.com>
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. The name of the author may not be used to endorse or promote products
  20  *    derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include "defs.h"
  35 #include <sys/param.h>
  36
  37 /* for struct iovec */
  38 #include <sys/uio.h>
  39
  40 #include "regs.h"
  41 #include "ptrace.h"
  42
  43 #if defined(SPARC64)
  44 # undef PTRACE_GETREGS
  45 # define PTRACE_GETREGS PTRACE_GETREGS64
  46 # undef PTRACE_SETREGS
  47 # define PTRACE_SETREGS PTRACE_SETREGS64
  48 #endif
  49
  50 #if defined SPARC64
  51 # include <asm/psrcompat.h>
  52 #elif defined SPARC
  53 # include <asm/psr.h>
  54 #endif
  55
  56 #ifndef NT_PRSTATUS
  57 # define NT_PRSTATUS 1
  58 #endif
  59
  60 #ifndef NSIG
  61 # warning: NSIG is not defined, using 32
  62 # define NSIG 32
  63 #endif
  64
  65 #include "syscall.h"
  66
  67 /* Define these shorthand notations to simplify the syscallent files. */
  68 #define TD TRACE_DESC
  69 #define TF TRACE_FILE
  70 #define TI TRACE_IPC
  71 #define TN TRACE_NETWORK
  72 #define TP TRACE_PROCESS
  73 #define TS TRACE_SIGNAL
  74 #define TM TRACE_MEMORY
  75 #define NF SYSCALL_NEVER_FAILS
  76 #define MA MAX_ARGS
  77 #define SI STACKTRACE_INVALIDATE_CACHE
  78 #define SE STACKTRACE_CAPTURE_ON_ENTER
  79
  80 const struct_sysent sysent0[] = {
  81 #include "syscallent.h"
  82 };
  83
  84 #if SUPPORTED_PERSONALITIES > 1
  85 static const struct_sysent sysent1[] = {
  86 # include "syscallent1.h"
  87 };
  88 #endif
  89
  90 #if SUPPORTED_PERSONALITIES > 2
  91 static const struct_sysent sysent2[] = {
  92 # include "syscallent2.h"
  93 };
  94 #endif
  95
  96 /* Now undef them since short defines cause wicked namespace pollution. */
  97 #undef TD
  98 #undef TF
  99 #undef TI
 100 #undef TN
 101 #undef TP
 102 #undef TS
 103 #undef TM
 104 #undef NF
 105 #undef MA
 106 #undef SI
 107 #undef SE
 108
 109 /*
 110  * `ioctlent[012].h' files are automatically generated by the auxiliary
 111  * program `ioctlsort', such that the list is sorted by the `code' field.
 112  * This has the side-effect of resolving the _IO.. macros into
 113  * plain integers, eliminating the need to include here everything
 114  * in "/usr/include".
 115  */
 116
 117 const char *const errnoent0[] = {
 118 #include "errnoent.h"
 119 };
 120 const char *const signalent0[] = {
 121 #include "signalent.h"
 122 };
 123 const struct_ioctlent ioctlent0[] = {
 124 #include "ioctlent0.h"
 125 };
 126
 127 #if SUPPORTED_PERSONALITIES > 1
 128 static const char *const errnoent1[] = {
 129 # include "errnoent1.h"
 130 };
 131 static const char *const signalent1[] = {
 132 # include "signalent1.h"
 133 };
 134 static const struct_ioctlent ioctlent1[] = {
 135 # include "ioctlent1.h"
 136 };
 137 #endif
 138
 139 #if SUPPORTED_PERSONALITIES > 2
 140 static const char *const errnoent2[] = {
 141 # include "errnoent2.h"
 142 };
 143 static const char *const signalent2[] = {
 144 # include "signalent2.h"
 145 };
 146 static const struct_ioctlent ioctlent2[] = {
 147 # include "ioctlent2.h"
 148 };
 149 #endif
 150
 151 enum {
 152         nsyscalls0 = ARRAY_SIZE(sysent0)
 153 #if SUPPORTED_PERSONALITIES > 1
 154         , nsyscalls1 = ARRAY_SIZE(sysent1)
 155 # if SUPPORTED_PERSONALITIES > 2
 156         , nsyscalls2 = ARRAY_SIZE(sysent2)
 157 # endif
 158 #endif
 159 };
 160
 161 enum {
 162         nerrnos0 = ARRAY_SIZE(errnoent0)
 163 #if SUPPORTED_PERSONALITIES > 1
 164         , nerrnos1 = ARRAY_SIZE(errnoent1)
 165 # if SUPPORTED_PERSONALITIES > 2
 166         , nerrnos2 = ARRAY_SIZE(errnoent2)
 167 # endif
 168 #endif
 169 };
 170
 171 enum {
 172         nsignals0 = ARRAY_SIZE(signalent0)
 173 #if SUPPORTED_PERSONALITIES > 1
 174         , nsignals1 = ARRAY_SIZE(signalent1)
 175 # if SUPPORTED_PERSONALITIES > 2
 176         , nsignals2 = ARRAY_SIZE(signalent2)
 177 # endif
 178 #endif
 179 };
 180
 181 enum {
 182         nioctlents0 = ARRAY_SIZE(ioctlent0)
 183 #if SUPPORTED_PERSONALITIES > 1
 184         , nioctlents1 = ARRAY_SIZE(ioctlent1)
 185 # if SUPPORTED_PERSONALITIES > 2
 186         , nioctlents2 = ARRAY_SIZE(ioctlent2)
 187 # endif
 188 #endif
 189 };
 190
 191 #if SUPPORTED_PERSONALITIES > 1
 192 const struct_sysent *sysent = sysent0;
 193 const char *const *errnoent = errnoent0;
 194 const char *const *signalent = signalent0;
 195 const struct_ioctlent *ioctlent = ioctlent0;
 196 #endif
 197 unsigned nsyscalls = nsyscalls0;
 198 unsigned nerrnos = nerrnos0;
 199 unsigned nsignals = nsignals0;
 200 unsigned nioctlents = nioctlents0;
 201
 202 unsigned num_quals;
 203 qualbits_t *qual_vec[SUPPORTED_PERSONALITIES];
 204
 205 static const unsigned nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 206         nsyscalls0,
 207 #if SUPPORTED_PERSONALITIES > 1
 208         nsyscalls1,
 209 #endif
 210 #if SUPPORTED_PERSONALITIES > 2
 211         nsyscalls2,
 212 #endif
 213 };
 214 static const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 215         sysent0,
 216 #if SUPPORTED_PERSONALITIES > 1
 217         sysent1,
 218 #endif
 219 #if SUPPORTED_PERSONALITIES > 2
 220         sysent2,
 221 #endif
 222 };
 223
 224 enum {
 225         MAX_NSYSCALLS1 = (nsyscalls0
 226 #if SUPPORTED_PERSONALITIES > 1
 227                         > nsyscalls1 ? nsyscalls0 : nsyscalls1
 228 #endif
 229                         ),
 230         MAX_NSYSCALLS2 = (MAX_NSYSCALLS1
 231 #if SUPPORTED_PERSONALITIES > 2
 232                         > nsyscalls2 ? MAX_NSYSCALLS1 : nsyscalls2
 233 #endif
 234                         ),
 235         MAX_NSYSCALLS = MAX_NSYSCALLS2,
 236         /* We are ready for arches with up to 255 signals,
 237          * even though the largest known signo is on MIPS and it is 128.
 238          * The number of existing syscalls on all arches is
 239          * larger that 255 anyway, so it is just a pedantic matter.
 240          */
 241         MIN_QUALS = MAX_NSYSCALLS > 255 ? MAX_NSYSCALLS : 255
 242 };
 243
 244 #if SUPPORTED_PERSONALITIES > 1
 245 unsigned current_personality;
 246
 247 # ifndef current_wordsize
 248 unsigned current_wordsize;
 249 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 250         PERSONALITY0_WORDSIZE,
 251         PERSONALITY1_WORDSIZE,
 252 # if SUPPORTED_PERSONALITIES > 2
 253         PERSONALITY2_WORDSIZE,
 254 # endif
 255 };
 256 # endif
 257
 258 void
 259 set_personality(int personality)
 260 {
 261         nsyscalls = nsyscall_vec[personality];
 262         sysent = sysent_vec[personality];
 263
 264         switch (personality) {
 265         case 0:
 266                 errnoent = errnoent0;
 267                 nerrnos = nerrnos0;
 268                 ioctlent = ioctlent0;
 269                 nioctlents = nioctlents0;
 270                 signalent = signalent0;
 271                 nsignals = nsignals0;
 272                 break;
 273
 274         case 1:
 275                 errnoent = errnoent1;
 276                 nerrnos = nerrnos1;
 277                 ioctlent = ioctlent1;
 278                 nioctlents = nioctlents1;
 279                 signalent = signalent1;
 280                 nsignals = nsignals1;
 281                 break;
 282
 283 # if SUPPORTED_PERSONALITIES > 2
 284         case 2:
 285                 errnoent = errnoent2;
 286                 nerrnos = nerrnos2;
 287                 ioctlent = ioctlent2;
 288                 nioctlents = nioctlents2;
 289                 signalent = signalent2;
 290                 nsignals = nsignals2;
 291                 break;
 292 # endif
 293         }
 294
 295         current_personality = personality;
 296 # ifndef current_wordsize
 297         current_wordsize = personality_wordsize[personality];
 298 # endif
 299 }
 300
 301 static void
 302 update_personality(struct tcb *tcp, unsigned int personality)
 303 {
 304         if (personality == current_personality)
 305                 return;
 306         set_personality(personality);
 307
 308         if (personality == tcp->currpers)
 309                 return;
 310         tcp->currpers = personality;
 311
 312 # if defined(POWERPC64)
 313         if (!qflag) {
 314                 static const char *const names[] = {"64 bit", "32 bit"};
 315                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 316                         tcp->pid, names[personality]);
 317         }
 318 # elif defined(X86_64)
 319         if (!qflag) {
 320                 static const char *const names[] = {"64 bit", "32 bit", "x32"};
 321                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 322                         tcp->pid, names[personality]);
 323         }
 324 # elif defined(X32)
 325         if (!qflag) {
 326                 static const char *const names[] = {"x32", "32 bit"};
 327                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 328                         tcp->pid, names[personality]);
 329         }
 330 # elif defined(AARCH64)
 331         if (!qflag) {
 332                 static const char *const names[] = {"32-bit", "AArch64"};
 333                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 334                         tcp->pid, names[personality]);
 335         }
 336 # elif defined(TILE)
 337         if (!qflag) {
 338                 static const char *const names[] = {"64-bit", "32-bit"};
 339                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 340                         tcp->pid, names[personality]);
 341         }
 342 # endif
 343 }
 344 #endif
 345
 346 static int qual_syscall(), qual_signal(), qual_desc();
 347
 348 static const struct qual_options {
 349         unsigned int bitflag;
 350         const char *option_name;
 351         int (*qualify)(const char *, int, int);
 352         const char *argument_name;
 353 } qual_options[] = {
 354         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
 355         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
 356         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
 357         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
 358         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
 359         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
 360         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
 361         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
 362         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
 363         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
 364         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
 365         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
 366         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
 367         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
 368         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
 369         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
 370         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
 371         { 0,            NULL,           NULL,           NULL            },
 372 };
 373
 374 static void
 375 reallocate_qual(const unsigned int n)
 376 {
 377         unsigned p;
 378         qualbits_t *qp;
 379         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 380                 qp = qual_vec[p] = realloc(qual_vec[p], n * sizeof(qualbits_t));
 381                 if (!qp)
 382                         die_out_of_memory();
 383                 memset(&qp[num_quals], 0, (n - num_quals) * sizeof(qualbits_t));
 384         }
 385         num_quals = n;
 386 }
 387
 388 static void
 389 qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
 390 {
 391         int p;
 392
 393         if (num_quals <= n)
 394                 reallocate_qual(n + 1);
 395
 396         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 397                 if (pers == p || pers < 0) {
 398                         if (not)
 399                                 qual_vec[p][n] &= ~bitflag;
 400                         else
 401                                 qual_vec[p][n] |= bitflag;
 402                 }
 403         }
 404 }
 405
 406 static int
 407 qual_syscall(const char *s, const unsigned int bitflag, const int not)
 408 {
 409         int p;
 410         unsigned int i;
 411         int rc = -1;
 412
 413         if (*s >= '0' && *s <= '9') {
 414                 i = string_to_uint(s);
 415                 if (i >= MAX_NSYSCALLS)
 416                         return -1;
 417                 qualify_one(i, bitflag, not, -1);
 418                 return 0;
 419         }
 420
 421         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 422                 for (i = 0; i < nsyscall_vec[p]; i++) {
 423                         if (sysent_vec[p][i].sys_name
 424                          && strcmp(s, sysent_vec[p][i].sys_name) == 0
 425                         ) {
 426                                 qualify_one(i, bitflag, not, p);
 427                                 rc = 0;
 428                         }
 429                 }
 430         }
 431
 432         return rc;
 433 }
 434
 435 static int
 436 qual_signal(const char *s, const unsigned int bitflag, const int not)
 437 {
 438         unsigned int i;
 439
 440         if (*s >= '0' && *s <= '9') {
 441                 int signo = string_to_uint(s);
 442                 if (signo < 0 || signo > 255)
 443                         return -1;
 444                 qualify_one(signo, bitflag, not, -1);
 445                 return 0;
 446         }
 447         if (strncasecmp(s, "SIG", 3) == 0)
 448                 s += 3;
 449         for (i = 0; i <= NSIG; i++) {
 450                 if (strcasecmp(s, signame(i) + 3) == 0) {
 451                         qualify_one(i, bitflag, not, -1);
 452                         return 0;
 453                 }
 454         }
 455         return -1;
 456 }
 457
 458 static int
 459 qual_desc(const char *s, const unsigned int bitflag, const int not)
 460 {
 461         if (*s >= '0' && *s <= '9') {
 462                 int desc = string_to_uint(s);
 463                 if (desc < 0 || desc > 0x7fff) /* paranoia */
 464                         return -1;
 465                 qualify_one(desc, bitflag, not, -1);
 466                 return 0;
 467         }
 468         return -1;
 469 }
 470
 471 static int
 472 lookup_class(const char *s)
 473 {
 474         if (strcmp(s, "file") == 0)
 475                 return TRACE_FILE;
 476         if (strcmp(s, "ipc") == 0)
 477                 return TRACE_IPC;
 478         if (strcmp(s, "network") == 0)
 479                 return TRACE_NETWORK;
 480         if (strcmp(s, "process") == 0)
 481                 return TRACE_PROCESS;
 482         if (strcmp(s, "signal") == 0)
 483                 return TRACE_SIGNAL;
 484         if (strcmp(s, "desc") == 0)
 485                 return TRACE_DESC;
 486         if (strcmp(s, "memory") == 0)
 487                 return TRACE_MEMORY;
 488         return -1;
 489 }
 490
 491 void
 492 qualify(const char *s)
 493 {
 494         const struct qual_options *opt;
 495         char *copy;
 496         const char *p;
 497         int not;
 498         unsigned int i;
 499
 500         if (num_quals == 0)
 501                 reallocate_qual(MIN_QUALS);
 502
 503         opt = &qual_options[0];
 504         for (i = 0; (p = qual_options[i].option_name); i++) {
 505                 unsigned int len = strlen(p);
 506                 if (strncmp(s, p, len) == 0 && s[len] == '=') {
 507                         opt = &qual_options[i];
 508                         s += len + 1;
 509                         break;
 510                 }
 511         }
 512         not = 0;
 513         if (*s == '!') {
 514                 not = 1;
 515                 s++;
 516         }
 517         if (strcmp(s, "none") == 0) {
 518                 not = 1 - not;
 519                 s = "all";
 520         }
 521         if (strcmp(s, "all") == 0) {
 522                 for (i = 0; i < num_quals; i++) {
 523                         qualify_one(i, opt->bitflag, not, -1);
 524                 }
 525                 return;
 526         }
 527         for (i = 0; i < num_quals; i++) {
 528                 qualify_one(i, opt->bitflag, !not, -1);
 529         }
 530         copy = strdup(s);
 531         if (!copy)
 532                 die_out_of_memory();
 533         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
 534                 int n;
 535                 if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
 536                         unsigned pers;
 537                         for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
 538                                 for (i = 0; i < nsyscall_vec[pers]; i++)
 539                                         if (sysent_vec[pers][i].sys_flags & n)
 540                                                 qualify_one(i, opt->bitflag, not, pers);
 541                         }
 542                         continue;
 543                 }
 544                 if (opt->qualify(p, opt->bitflag, not)) {
 545                         error_msg_and_die("invalid %s '%s'",
 546                                 opt->argument_name, p);
 547                 }
 548         }
 549         free(copy);
 550         return;
 551 }
 552
 553 #ifdef SYS_socket_subcall
 554 static void
 555 decode_socket_subcall(struct tcb *tcp)
 556 {
 557         unsigned long addr;
 558         unsigned int i, n, size;
 559
 560         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_socket_nsubcalls)
 561                 return;
 562
 563         tcp->scno = SYS_socket_subcall + tcp->u_arg[0];
 564         tcp->qual_flg = qual_flags[tcp->scno];
 565         tcp->s_ent = &sysent[tcp->scno];
 566         addr = tcp->u_arg[1];
 567         size = current_wordsize;
 568         n = tcp->s_ent->nargs;
 569         for (i = 0; i < n; ++i) {
 570                 if (size == sizeof(int)) {
 571                         unsigned int arg;
 572                         if (umove(tcp, addr, &arg) < 0)
 573                                 arg = 0;
 574                         tcp->u_arg[i] = arg;
 575                 }
 576                 else {
 577                         unsigned long arg;
 578                         if (umove(tcp, addr, &arg) < 0)
 579                                 arg = 0;
 580                         tcp->u_arg[i] = arg;
 581                 }
 582                 addr += size;
 583         }
 584 }
 585 #endif
 586
 587 #ifdef SYS_ipc_subcall
 588 static void
 589 decode_ipc_subcall(struct tcb *tcp)
 590 {
 591         unsigned int i, n;
 592
 593         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_ipc_nsubcalls)
 594                 return;
 595
 596         tcp->scno = SYS_ipc_subcall + tcp->u_arg[0];
 597         tcp->qual_flg = qual_flags[tcp->scno];
 598         tcp->s_ent = &sysent[tcp->scno];
 599         n = tcp->s_ent->nargs;
 600         for (i = 0; i < n; i++)
 601                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 602 }
 603 #endif
 604
 605 int
 606 printargs(struct tcb *tcp)
 607 {
 608         if (entering(tcp)) {
 609                 int i;
 610                 int n = tcp->s_ent->nargs;
 611                 for (i = 0; i < n; i++)
 612                         tprintf("%s%#lx", i ? ", " : "", tcp->u_arg[i]);
 613         }
 614         return 0;
 615 }
 616
 617 int
 618 printargs_lu(struct tcb *tcp)
 619 {
 620         if (entering(tcp)) {
 621                 int i;
 622                 int n = tcp->s_ent->nargs;
 623                 for (i = 0; i < n; i++)
 624                         tprintf("%s%lu", i ? ", " : "", tcp->u_arg[i]);
 625         }
 626         return 0;
 627 }
 628
 629 int
 630 printargs_ld(struct tcb *tcp)
 631 {
 632         if (entering(tcp)) {
 633                 int i;
 634                 int n = tcp->s_ent->nargs;
 635                 for (i = 0; i < n; i++)
 636                         tprintf("%s%ld", i ? ", " : "", tcp->u_arg[i]);
 637         }
 638         return 0;
 639 }
 640
 641 #if defined(SPARC) || defined(SPARC64) || defined(IA64) || defined(SH)
 642 long
 643 getrval2(struct tcb *tcp)
 644 {
 645         long val;
 646
 647 # if defined(SPARC) || defined(SPARC64)
 648         val = sparc_regs.u_regs[U_REG_O1];
 649 # elif defined(SH)
 650         if (upeek(tcp->pid, 4*(REG_REG0+1), &val) < 0)
 651                 return -1;
 652 # elif defined(IA64)
 653         if (upeek(tcp->pid, PT_R9, &val) < 0)
 654                 return -1;
 655 # endif
 656
 657         return val;
 658 }
 659 #endif
 660
 661 #if defined(I386)
 662 static struct user_regs_struct i386_regs;
 663 long *const i386_esp_ptr = &i386_regs.esp;
 664 # define ARCH_REGS_FOR_GETREGS i386_regs
 665 #elif defined(X86_64) || defined(X32)
 666 /*
 667  * On i386, pt_regs and user_regs_struct are the same,
 668  * but on 64 bit x86, user_regs_struct has six more fields:
 669  * fs_base, gs_base, ds, es, fs, gs.
 670  * PTRACE_GETREGS fills them too, so struct pt_regs would overflow.
 671  */
 672 struct i386_user_regs_struct {
 673         uint32_t ebx;
 674         uint32_t ecx;
 675         uint32_t edx;
 676         uint32_t esi;
 677         uint32_t edi;
 678         uint32_t ebp;
 679         uint32_t eax;
 680         uint32_t xds;
 681         uint32_t xes;
 682         uint32_t xfs;
 683         uint32_t xgs;
 684         uint32_t orig_eax;
 685         uint32_t eip;
 686         uint32_t xcs;
 687         uint32_t eflags;
 688         uint32_t esp;
 689         uint32_t xss;
 690 };
 691 static union {
 692         struct user_regs_struct      x86_64_r;
 693         struct i386_user_regs_struct i386_r;
 694 } x86_regs_union;
 695 # define x86_64_regs x86_regs_union.x86_64_r
 696 # define i386_regs   x86_regs_union.i386_r
 697 uint32_t *const i386_esp_ptr = &i386_regs.esp;
 698 uint64_t *const x86_64_rsp_ptr = (uint64_t *) &x86_64_regs.rsp;
 699 static struct iovec x86_io = {
 700         .iov_base = &x86_regs_union
 701 };
 702 # define ARCH_REGS_FOR_GETREGSET x86_regs_union
 703 # define ARCH_IOVEC_FOR_GETREGSET x86_io
 704 #elif defined(IA64)
 705 static bool ia64_ia32mode;
 706 static long ia64_r8, ia64_r10;
 707 #elif defined(POWERPC)
 708 struct pt_regs ppc_regs; /* not static */
 709 # define ARCH_REGS_FOR_GETREGS ppc_regs
 710 #elif defined(M68K)
 711 static long m68k_d0;
 712 #elif defined(BFIN)
 713 static long bfin_r0;
 714 #elif defined(ARM)
 715 static struct pt_regs arm_regs;
 716 long *const arm_sp_ptr = &arm_regs.ARM_sp;
 717 # define ARCH_REGS_FOR_GETREGS arm_regs
 718 #elif defined(AARCH64)
 719 struct arm_pt_regs {
 720         int uregs[18];
 721 };
 722 # define ARM_cpsr       uregs[16]
 723 # define ARM_pc         uregs[15]
 724 # define ARM_lr         uregs[14]
 725 # define ARM_sp         uregs[13]
 726 # define ARM_ip         uregs[12]
 727 # define ARM_fp         uregs[11]
 728 # define ARM_r10        uregs[10]
 729 # define ARM_r9         uregs[9]
 730 # define ARM_r8         uregs[8]
 731 # define ARM_r7         uregs[7]
 732 # define ARM_r6         uregs[6]
 733 # define ARM_r5         uregs[5]
 734 # define ARM_r4         uregs[4]
 735 # define ARM_r3         uregs[3]
 736 # define ARM_r2         uregs[2]
 737 # define ARM_r1         uregs[1]
 738 # define ARM_r0         uregs[0]
 739 # define ARM_ORIG_r0    uregs[17]
 740 static union {
 741         struct user_pt_regs aarch64_r;
 742         struct arm_pt_regs  arm_r;
 743 } arm_regs_union;
 744 # define aarch64_regs arm_regs_union.aarch64_r
 745 # define arm_regs     arm_regs_union.arm_r
 746 uint64_t *const aarch64_sp_ptr = (uint64_t *) &aarch64_regs.sp;
 747 uint32_t *const arm_sp_ptr = (uint32_t *) &arm_regs.ARM_sp;
 748 static struct iovec aarch64_io = {
 749         .iov_base = &arm_regs_union
 750 };
 751 # define ARCH_REGS_FOR_GETREGSET arm_regs_union
 752 # define ARCH_IOVEC_FOR_GETREGSET aarch64_io
 753 #elif defined(ALPHA)
 754 static long alpha_r0;
 755 static long alpha_a3;
 756 #elif defined(AVR32)
 757 static struct pt_regs avr32_regs;
 758 # define ARCH_REGS_FOR_GETREGS avr32_regs
 759 #elif defined(SPARC) || defined(SPARC64)
 760 struct pt_regs sparc_regs; /* not static */
 761 # define ARCH_REGS_FOR_GETREGS sparc_regs
 762 #elif defined(MIPS)
 763 struct mips_regs mips_regs; /* not static */
 764 /* PTRACE_GETREGS on MIPS is available since linux v2.6.15. */
 765 # define ARCH_REGS_FOR_GETREGS mips_regs
 766 #elif defined(S390) || defined(S390X)
 767 static long s390_gpr2;
 768 #elif defined(HPPA)
 769 static long hppa_r28;
 770 #elif defined(SH)
 771 static long sh_r0;
 772 #elif defined(SH64)
 773 static long sh64_r9;
 774 #elif defined(CRISV10) || defined(CRISV32)
 775 static long cris_r10;
 776 #elif defined(TILE)
 777 struct pt_regs tile_regs; /* not static */
 778 # define ARCH_REGS_FOR_GETREGS tile_regs
 779 #elif defined(MICROBLAZE)
 780 static long microblaze_r3;
 781 #elif defined(OR1K)
 782 static struct user_regs_struct or1k_regs;
 783 # define ARCH_REGS_FOR_GETREGSET or1k_regs
 784 #elif defined(METAG)
 785 static struct user_gp_regs metag_regs;
 786 # define ARCH_REGS_FOR_GETREGSET metag_regs
 787 #elif defined(XTENSA)
 788 static long xtensa_a2;
 789 # elif defined(ARC)
 790 static struct user_regs_struct arc_regs;
 791 # define ARCH_REGS_FOR_GETREGSET arc_regs
 792 #endif
 793
 794 static long get_regs_error;
 795
 796 void
 797 print_pc(struct tcb *tcp)
 798 {
 799         const char *fmt;
 800         const char *bad;
 801
 802 #ifdef current_wordsize
 803 # define pc_wordsize current_wordsize
 804 #else
 805 # define pc_wordsize personality_wordsize[tcp->currpers]
 806 #endif
 807
 808         if (pc_wordsize == 4) {
 809                 fmt = "[%08lx] ";
 810                 bad = "[????????] ";
 811         } else {
 812                 fmt = "[%016lx] ";
 813                 bad = "[????????????????] ";
 814         }
 815
 816 #undef pc_wordsize
 817 #define PRINTBADPC tprints(bad)
 818
 819         if (get_regs_error) {
 820                 PRINTBADPC;
 821                 return;
 822         }
 823
 824 #if defined(I386)
 825         tprintf(fmt, i386_regs.eip);
 826 #elif defined(X86_64) || defined(X32)
 827         if (x86_io.iov_len == sizeof(i386_regs))
 828                 tprintf(fmt, (unsigned long) i386_regs.eip);
 829         else
 830                 tprintf(fmt, (unsigned long) x86_64_regs.rip);
 831 #elif defined(S390) || defined(S390X)
 832         long psw;
 833         if (upeek(tcp->pid, PT_PSWADDR, &psw) < 0) {
 834                 PRINTBADPC;
 835                 return;
 836         }
 837         tprintf(fmt, psw);
 838 #elif defined(IA64)
 839         long ip;
 840         if (upeek(tcp->pid, PT_B0, &ip) < 0) {
 841                 PRINTBADPC;
 842                 return;
 843         }
 844         tprintf(fmt, ip);
 845 #elif defined(POWERPC)
 846         tprintf(fmt, ppc_regs.nip);
 847 #elif defined(M68K)
 848         long pc;
 849         if (upeek(tcp->pid, 4*PT_PC, &pc) < 0) {
 850                 PRINTBADPC;
 851                 return;
 852         }
 853         tprintf(fmt, pc);
 854 #elif defined(ALPHA)
 855         long pc;
 856         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
 857                 PRINTBADPC;
 858                 return;
 859         }
 860         tprintf(fmt, pc);
 861 #elif defined(SPARC)
 862         tprintf(fmt, sparc_regs.pc);
 863 #elif defined(SPARC64)
 864         tprintf(fmt, sparc_regs.tpc);
 865 #elif defined(HPPA)
 866         long pc;
 867         if (upeek(tcp->pid, PT_IAOQ0, &pc) < 0) {
 868                 PRINTBADPC;
 869                 return;
 870         }
 871         tprintf(fmt, pc);
 872 #elif defined MIPS
 873         tprintf(fmt, (unsigned long) mips_REG_EPC);
 874 #elif defined(SH)
 875         long pc;
 876         if (upeek(tcp->pid, 4*REG_PC, &pc) < 0) {
 877                 PRINTBADPC;
 878                 return;
 879         }
 880         tprintf(fmt, pc);
 881 #elif defined(SH64)
 882         long pc;
 883         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
 884                 PRINTBADPC;
 885                 return;
 886         }
 887         tprintf(fmt, pc);
 888 #elif defined(AARCH64)
 889         if (aarch64_io.iov_len == sizeof(arm_regs))
 890                 tprintf(fmt, (unsigned long) arm_regs.ARM_pc);
 891         else
 892                 tprintf(fmt, (unsigned long) aarch64_regs.pc);
 893 #elif defined(ARM)
 894         tprintf(fmt, arm_regs.ARM_pc);
 895 #elif defined(AVR32)
 896         tprintf(fmt, avr32_regs.pc);
 897 #elif defined(BFIN)
 898         long pc;
 899         if (upeek(tcp->pid, PT_PC, &pc) < 0) {
 900                 PRINTBADPC;
 901                 return;
 902         }
 903         tprintf(fmt, pc);
 904 #elif defined(CRISV10)
 905         long pc;
 906         if (upeek(tcp->pid, 4*PT_IRP, &pc) < 0) {
 907                 PRINTBADPC;
 908                 return;
 909         }
 910         tprintf(fmt, pc);
 911 #elif defined(CRISV32)
 912         long pc;
 913         if (upeek(tcp->pid, 4*PT_ERP, &pc) < 0) {
 914                 PRINTBADPC;
 915                 return;
 916         }
 917         tprintf(fmt, pc);
 918 #elif defined(TILE)
 919         tprintf(fmt, (unsigned long) tile_regs.pc);
 920 #elif defined(OR1K)
 921         tprintf(fmt, or1k_regs.pc);
 922 #elif defined(METAG)
 923         tprintf(fmt, metag_regs.pc);
 924 #elif defined(XTENSA)
 925         long pc;
 926         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
 927                 PRINTBADPC;
 928                 return;
 929         }
 930         tprintf(fmt, pc);
 931 #elif defined(ARC)
 932         tprintf(fmt, arc_regs.efa);
 933 #else
 934 # warning print_pc is not implemented for this architecture
 935         PRINTBADPC;
 936 #endif /* architecture */
 937 }
 938
 939 /*
 940  * Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 941  * The shuffling should be an involution: shuffle_scno(shuffle_scno(n)) == n.
 942  */
 943 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
 944 static long
 945 shuffle_scno(unsigned long scno)
 946 {
 947         if (scno < ARM_FIRST_SHUFFLED_SYSCALL)
 948                 return scno;
 949
 950         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 951         if (scno == ARM_FIRST_SHUFFLED_SYSCALL)
 952                 return 0x000ffff0;
 953         if (scno == 0x000ffff0)
 954                 return ARM_FIRST_SHUFFLED_SYSCALL;
 955
 956 #define ARM_SECOND_SHUFFLED_SYSCALL (ARM_FIRST_SHUFFLED_SYSCALL + 1)
 957         /*
 958          * Is it ARM specific syscall?
 959          * Swap [0x000f0000, 0x000f0000 + LAST_SPECIAL] range
 960          * with [SECOND_SHUFFLED, SECOND_SHUFFLED + LAST_SPECIAL] range.
 961          */
 962         if (scno >= 0x000f0000 &&
 963             scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL) {
 964                 return scno - 0x000f0000 + ARM_SECOND_SHUFFLED_SYSCALL;
 965         }
 966         if (scno <= ARM_SECOND_SHUFFLED_SYSCALL + ARM_LAST_SPECIAL_SYSCALL) {
 967                 return scno + 0x000f0000 - ARM_SECOND_SHUFFLED_SYSCALL;
 968         }
 969
 970         return scno;
 971 }
 972 #else
 973 # define shuffle_scno(scno) ((long)(scno))
 974 #endif
 975
 976 static char*
 977 undefined_scno_name(struct tcb *tcp)
 978 {
 979         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
 980
 981         sprintf(buf, "syscall_%lu", shuffle_scno(tcp->scno));
 982         return buf;
 983 }
 984
 985 #ifdef POWERPC
 986 /*
 987  * PTRACE_GETREGS was added to the PowerPC kernel in v2.6.23,
 988  * we provide a slow fallback for old kernels.
 989  */
 990 static int powerpc_getregs_old(pid_t pid)
 991 {
 992         int i;
 993         long r;
 994
 995         if (iflag) {
 996                 r = upeek(pid, sizeof(long) * PT_NIP, (long *)&ppc_regs.nip);
 997                 if (r)
 998                         goto out;
 999         }
1000 #ifdef POWERPC64 /* else we never use it */
1001         r = upeek(pid, sizeof(long) * PT_MSR, (long *)&ppc_regs.msr);
1002         if (r)
1003                 goto out;
1004 #endif
1005         r = upeek(pid, sizeof(long) * PT_CCR, (long *)&ppc_regs.ccr);
1006         if (r)
1007                 goto out;
1008         r = upeek(pid, sizeof(long) * PT_ORIG_R3, (long *)&ppc_regs.orig_gpr3);
1009         if (r)
1010                 goto out;
1011         for (i = 0; i <= 8; i++) {
1012                 r = upeek(pid, sizeof(long) * (PT_R0 + i),
1013                           (long *)&ppc_regs.gpr[i]);
1014                 if (r)
1015                         goto out;
1016         }
1017  out:
1018         return r;
1019 }
1020 #endif
1021
1022 void
1023 clear_regs(void)
1024 {
1025         get_regs_error = -1;
1026 }
1027
1028 #if defined ARCH_REGS_FOR_GETREGSET
1029 static long
1030 get_regset(pid_t pid)
1031 {
1032 # ifdef ARCH_IOVEC_FOR_GETREGSET
1033         /* variable iovec */
1034         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1035         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1036                       &ARCH_IOVEC_FOR_GETREGSET);
1037 # else
1038         /* constant iovec */
1039         static struct iovec io = {
1040                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1041                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1042         };
1043         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1044
1045 # endif
1046 }
1047 #endif /* ARCH_REGS_FOR_GETREGSET */
1048
1049 void
1050 get_regs(pid_t pid)
1051 {
1052 #ifdef ARCH_REGS_FOR_GETREGSET
1053 # ifdef X86_64
1054         /* Try PTRACE_GETREGSET first, fallback to PTRACE_GETREGS. */
1055         static int getregset_support;
1056
1057         if (getregset_support >= 0) {
1058                 get_regs_error = get_regset(pid);
1059                 if (getregset_support > 0)
1060                         return;
1061                 if (get_regs_error >= 0) {
1062                         getregset_support = 1;
1063                         return;
1064                 }
1065                 if (errno == EPERM || errno == ESRCH)
1066                         return;
1067                 getregset_support = -1;
1068         }
1069         /* Use old method, with unreliable heuristical detection of 32-bitness. */
1070         x86_io.iov_len = sizeof(x86_64_regs);
1071         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &x86_64_regs);
1072         if (!get_regs_error && x86_64_regs.cs == 0x23) {
1073                 x86_io.iov_len = sizeof(i386_regs);
1074                 /*
1075                  * The order is important: i386_regs and x86_64_regs
1076                  * are overlaid in memory!
1077                  */
1078                 i386_regs.ebx = x86_64_regs.rbx;
1079                 i386_regs.ecx = x86_64_regs.rcx;
1080                 i386_regs.edx = x86_64_regs.rdx;
1081                 i386_regs.esi = x86_64_regs.rsi;
1082                 i386_regs.edi = x86_64_regs.rdi;
1083                 i386_regs.ebp = x86_64_regs.rbp;
1084                 i386_regs.eax = x86_64_regs.rax;
1085                 /* i386_regs.xds = x86_64_regs.ds; unused by strace */
1086                 /* i386_regs.xes = x86_64_regs.es; ditto... */
1087                 /* i386_regs.xfs = x86_64_regs.fs; */
1088                 /* i386_regs.xgs = x86_64_regs.gs; */
1089                 i386_regs.orig_eax = x86_64_regs.orig_rax;
1090                 i386_regs.eip = x86_64_regs.rip;
1091                 /* i386_regs.xcs = x86_64_regs.cs; */
1092                 /* i386_regs.eflags = x86_64_regs.eflags; */
1093                 i386_regs.esp = x86_64_regs.rsp;
1094                 /* i386_regs.xss = x86_64_regs.ss; */
1095         }
1096 # else /* !X86_64 */
1097         /* Assume that PTRACE_GETREGSET works. */
1098         get_regs_error = get_regset(pid);
1099 # endif
1100 #elif defined ARCH_REGS_FOR_GETREGS
1101 # if defined SPARC || defined SPARC64
1102         /* SPARC systems have the meaning of data and addr reversed */
1103         get_regs_error = ptrace(PTRACE_GETREGS, pid, (char *)&ARCH_REGS_FOR_GETREGS, 0);
1104 # elif defined POWERPC
1105         static bool old_kernel = 0;
1106         if (old_kernel)
1107                 goto old;
1108         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1109         if (get_regs_error && errno == EIO) {
1110                 old_kernel = 1;
1111  old:
1112                 get_regs_error = powerpc_getregs_old(pid);
1113         }
1114 # else
1115         /* Assume that PTRACE_GETREGS works. */
1116         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1117 # endif
1118
1119 #else /* !ARCH_REGS_FOR_GETREGSET && !ARCH_REGS_FOR_GETREGS */
1120 #  warning get_regs is not implemented for this architecture yet
1121         get_regs_error = 0;
1122 #endif
1123 }
1124
1125 /* Returns:
1126  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1127  * 1: ok, continue in trace_syscall_entering().
1128  * other: error, trace_syscall_entering() should print error indicator
1129  *    ("????" etc) and bail out.
1130  */
1131 static int
1132 get_scno(struct tcb *tcp)
1133 {
1134         long scno = 0;
1135
1136 #if defined(S390) || defined(S390X)
1137         if (upeek(tcp->pid, PT_GPR2, &s390_gpr2) < 0)
1138                 return -1;
1139
1140         if (s390_gpr2 != -ENOSYS) {
1141                 /*
1142                  * Since kernel version 2.5.44 the scno gets passed in gpr2.
1143                  */
1144                 scno = s390_gpr2;
1145         } else {
1146                 /*
1147                  * Old style of "passing" the scno via the SVC instruction.
1148                  */
1149                 long psw;
1150                 long opcode, offset_reg, tmp;
1151                 void *svc_addr;
1152                 static const int gpr_offset[16] = {
1153                                 PT_GPR0,  PT_GPR1,  PT_ORIGGPR2, PT_GPR3,
1154                                 PT_GPR4,  PT_GPR5,  PT_GPR6,     PT_GPR7,
1155                                 PT_GPR8,  PT_GPR9,  PT_GPR10,    PT_GPR11,
1156                                 PT_GPR12, PT_GPR13, PT_GPR14,    PT_GPR15
1157                 };
1158
1159                 if (upeek(tcp->pid, PT_PSWADDR, &psw) < 0)
1160                         return -1;
1161                 errno = 0;
1162                 opcode = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)(psw - sizeof(long)), 0);
1163                 if (errno) {
1164                         perror_msg("peektext(psw-oneword)");
1165                         return -1;
1166                 }
1167
1168                 /*
1169                  *  We have to check if the SVC got executed directly or via an
1170                  *  EXECUTE instruction. In case of EXECUTE it is necessary to do
1171                  *  instruction decoding to derive the system call number.
1172                  *  Unfortunately the opcode sizes of EXECUTE and SVC are differently,
1173                  *  so that this doesn't work if a SVC opcode is part of an EXECUTE
1174                  *  opcode. Since there is no way to find out the opcode size this
1175                  *  is the best we can do...
1176                  */
1177                 if ((opcode & 0xff00) == 0x0a00) {
1178                         /* SVC opcode */
1179                         scno = opcode & 0xff;
1180                 }
1181                 else {
1182                         /* SVC got executed by EXECUTE instruction */
1183
1184                         /*
1185                          *  Do instruction decoding of EXECUTE. If you really want to
1186                          *  understand this, read the Principles of Operations.
1187                          */
1188                         svc_addr = (void *) (opcode & 0xfff);
1189
1190                         tmp = 0;
1191                         offset_reg = (opcode & 0x000f0000) >> 16;
1192                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1193                                 return -1;
1194                         svc_addr += tmp;
1195
1196                         tmp = 0;
1197                         offset_reg = (opcode & 0x0000f000) >> 12;
1198                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1199                                 return -1;
1200                         svc_addr += tmp;
1201
1202                         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, svc_addr, 0);
1203                         if (errno)
1204                                 return -1;
1205 # if defined(S390X)
1206                         scno >>= 48;
1207 # else
1208                         scno >>= 16;
1209 # endif
1210                         tmp = 0;
1211                         offset_reg = (opcode & 0x00f00000) >> 20;
1212                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1213                                 return -1;
1214
1215                         scno = (scno | tmp) & 0xff;
1216                 }
1217         }
1218 #elif defined(POWERPC)
1219         scno = ppc_regs.gpr[0];
1220 # ifdef POWERPC64
1221         unsigned int currpers;
1222
1223         /*
1224          * Check for 64/32 bit mode.
1225          * Embedded implementations covered by Book E extension of PPC use
1226          * bit 0 (CM) of 32-bit Machine state register (MSR).
1227          * Other implementations use bit 0 (SF) of 64-bit MSR.
1228          */
1229         currpers = (ppc_regs.msr & 0x8000000080000000) ? 0 : 1;
1230         update_personality(tcp, currpers);
1231 # endif
1232 #elif defined(AVR32)
1233         scno = avr32_regs.r8;
1234 #elif defined(BFIN)
1235         if (upeek(tcp->pid, PT_ORIG_P0, &scno))
1236                 return -1;
1237 #elif defined(I386)
1238         scno = i386_regs.orig_eax;
1239 #elif defined(X86_64) || defined(X32)
1240 # ifndef __X32_SYSCALL_BIT
1241 #  define __X32_SYSCALL_BIT     0x40000000
1242 # endif
1243         unsigned int currpers;
1244 # if 1
1245         /* GETREGSET of NT_PRSTATUS tells us regset size,
1246          * which unambiguously detects i386.
1247          *
1248          * Linux kernel distinguishes x86-64 and x32 processes
1249          * solely by looking at __X32_SYSCALL_BIT:
1250          * arch/x86/include/asm/compat.h::is_x32_task():
1251          * if (task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT)
1252          *         return true;
1253          */
1254         if (x86_io.iov_len == sizeof(i386_regs)) {
1255                 scno = i386_regs.orig_eax;
1256                 currpers = 1;
1257         } else {
1258                 scno = x86_64_regs.orig_rax;
1259                 currpers = 0;
1260                 if (scno & __X32_SYSCALL_BIT) {
1261                         /*
1262                          * Syscall number -1 requires special treatment:
1263                          * it might be a side effect of SECCOMP_RET_ERRNO
1264                          * filtering that sets orig_rax to -1
1265                          * in some versions of linux kernel.
1266                          * If that is the case, then
1267                          * __X32_SYSCALL_BIT logic does not apply.
1268                          */
1269                         if ((long long) x86_64_regs.orig_rax != -1) {
1270                                 scno -= __X32_SYSCALL_BIT;
1271                                 currpers = 2;
1272                         } else {
1273 #  ifdef X32
1274                                 currpers = 2;
1275 #  endif
1276                         }
1277                 }
1278         }
1279 # elif 0
1280         /* cs = 0x33 for long mode (native 64 bit and x32)
1281          * cs = 0x23 for compatibility mode (32 bit)
1282          * ds = 0x2b for x32 mode (x86-64 in 32 bit)
1283          */
1284         scno = x86_64_regs.orig_rax;
1285         switch (x86_64_regs.cs) {
1286                 case 0x23: currpers = 1; break;
1287                 case 0x33:
1288                         if (x86_64_regs.ds == 0x2b) {
1289                                 currpers = 2;
1290                                 scno &= ~__X32_SYSCALL_BIT;
1291                         } else
1292                                 currpers = 0;
1293                         break;
1294                 default:
1295                         fprintf(stderr, "Unknown value CS=0x%08X while "
1296                                  "detecting personality of process "
1297                                  "PID=%d\n", (int)x86_64_regs.cs, tcp->pid);
1298                         currpers = current_personality;
1299                         break;
1300         }
1301 # elif 0
1302         /* This version analyzes the opcode of a syscall instruction.
1303          * (int 0x80 on i386 vs. syscall on x86-64)
1304          * It works, but is too complicated, and strictly speaking, unreliable.
1305          */
1306         unsigned long call, rip = x86_64_regs.rip;
1307         /* sizeof(syscall) == sizeof(int 0x80) == 2 */
1308         rip -= 2;
1309         errno = 0;
1310         call = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)rip, (char *)0);
1311         if (errno)
1312                 fprintf(stderr, "ptrace_peektext failed: %s\n",
1313                                 strerror(errno));
1314         switch (call & 0xffff) {
1315                 /* x86-64: syscall = 0x0f 0x05 */
1316                 case 0x050f: currpers = 0; break;
1317                 /* i386: int 0x80 = 0xcd 0x80 */
1318                 case 0x80cd: currpers = 1; break;
1319                 default:
1320                         currpers = current_personality;
1321                         fprintf(stderr,
1322                                 "Unknown syscall opcode (0x%04X) while "
1323                                 "detecting personality of process "
1324                                 "PID=%d\n", (int)call, tcp->pid);
1325                         break;
1326         }
1327 # endif
1328
1329 # ifdef X32
1330         /* If we are built for a x32 system, then personality 0 is x32
1331          * (not x86_64), and stracing of x86_64 apps is not supported.
1332          * Stracing of i386 apps is still supported.
1333          */
1334         if (currpers == 0) {
1335                 fprintf(stderr, "syscall_%lu(...) in unsupported "
1336                                 "64-bit mode of process PID=%d\n",
1337                         scno, tcp->pid);
1338                 return 0;
1339         }
1340         currpers &= ~2; /* map 2,1 to 0,1 */
1341 # endif
1342         update_personality(tcp, currpers);
1343 #elif defined(IA64)
1344 #       define IA64_PSR_IS      ((long)1 << 34)
1345         long psr;
1346         if (upeek(tcp->pid, PT_CR_IPSR, &psr) >= 0)
1347                 ia64_ia32mode = ((psr & IA64_PSR_IS) != 0);
1348         if (ia64_ia32mode) {
1349                 if (upeek(tcp->pid, PT_R1, &scno) < 0)
1350                         return -1;
1351         } else {
1352                 if (upeek(tcp->pid, PT_R15, &scno) < 0)
1353                         return -1;
1354         }
1355 #elif defined(AARCH64)
1356         switch (aarch64_io.iov_len) {
1357                 case sizeof(aarch64_regs):
1358                         /* We are in 64-bit mode */
1359                         scno = aarch64_regs.regs[8];
1360                         update_personality(tcp, 1);
1361                         break;
1362                 case sizeof(arm_regs):
1363                         /* We are in 32-bit mode */
1364                         /* Note: we don't support OABI, unlike 32-bit ARM build */
1365                         scno = arm_regs.ARM_r7;
1366                         scno = shuffle_scno(scno);
1367                         update_personality(tcp, 0);
1368                         break;
1369         }
1370 #elif defined(ARM)
1371         if (arm_regs.ARM_ip != 0) {
1372                 /* It is not a syscall entry */
1373                 fprintf(stderr, "pid %d stray syscall exit\n", tcp->pid);
1374                 tcp->flags |= TCB_INSYSCALL;
1375                 return 0;
1376         }
1377         /* Note: we support only 32-bit CPUs, not 26-bit */
1378
1379 # if !defined(__ARM_EABI__) || ENABLE_ARM_OABI
1380         if (arm_regs.ARM_cpsr & 0x20)
1381                 /* Thumb mode */
1382                 goto scno_in_r7;
1383         /* ARM mode */
1384         /* Check EABI/OABI by examining SVC insn's low 24 bits */
1385         errno = 0;
1386         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(arm_regs.ARM_pc - 4), NULL);
1387         if (errno)
1388                 return -1;
1389         /* EABI syscall convention? */
1390         if ((unsigned long) scno != 0xef000000) {
1391                 /* No, it's OABI */
1392                 if ((scno & 0x0ff00000) != 0x0f900000) {
1393                         fprintf(stderr, "pid %d unknown syscall trap 0x%08lx\n",
1394                                 tcp->pid, scno);
1395                         return -1;
1396                 }
1397                 /* Fixup the syscall number */
1398                 scno &= 0x000fffff;
1399         } else {
1400  scno_in_r7:
1401                 scno = arm_regs.ARM_r7;
1402         }
1403 # else /* __ARM_EABI__ || !ENABLE_ARM_OABI */
1404         scno = arm_regs.ARM_r7;
1405 # endif
1406         scno = shuffle_scno(scno);
1407 #elif defined(M68K)
1408         if (upeek(tcp->pid, 4*PT_ORIG_D0, &scno) < 0)
1409                 return -1;
1410 #elif defined(MIPS)
1411         scno = mips_REG_V0;
1412
1413         if (!SCNO_IN_RANGE(scno)) {
1414                 if (mips_REG_A3 == 0 || mips_REG_A3 == (uint64_t) -1) {
1415                         if (debug_flag)
1416                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1417                         return 0;
1418                 }
1419         }
1420 #elif defined(ALPHA)
1421         if (upeek(tcp->pid, REG_A3, &alpha_a3) < 0)
1422                 return -1;
1423         if (upeek(tcp->pid, REG_R0, &scno) < 0)
1424                 return -1;
1425
1426         /*
1427          * Do some sanity checks to figure out if it's
1428          * really a syscall entry
1429          */
1430         if (!SCNO_IN_RANGE(scno)) {
1431                 if (alpha_a3 == 0 || alpha_a3 == -1) {
1432                         if (debug_flag)
1433                                 fprintf(stderr, "stray syscall exit: r0 = %ld\n", scno);
1434                         return 0;
1435                 }
1436         }
1437 #elif defined(SPARC) || defined(SPARC64)
1438         /* Disassemble the syscall trap. */
1439         /* Retrieve the syscall trap instruction. */
1440         unsigned long trap;
1441         errno = 0;
1442 # if defined(SPARC64)
1443         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.tpc, 0);
1444         trap >>= 32;
1445 # else
1446         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.pc, 0);
1447 # endif
1448         if (errno)
1449                 return -1;
1450
1451         /* Disassemble the trap to see what personality to use. */
1452         switch (trap) {
1453         case 0x91d02010:
1454                 /* Linux/SPARC syscall trap. */
1455                 update_personality(tcp, 0);
1456                 break;
1457         case 0x91d0206d:
1458                 /* Linux/SPARC64 syscall trap. */
1459                 update_personality(tcp, 2);
1460                 break;
1461         case 0x91d02000:
1462                 /* SunOS syscall trap. (pers 1) */
1463                 fprintf(stderr, "syscall: SunOS no support\n");
1464                 return -1;
1465         case 0x91d02008:
1466                 /* Solaris 2.x syscall trap. (per 2) */
1467                 update_personality(tcp, 1);
1468                 break;
1469         case 0x91d02009:
1470                 /* NetBSD/FreeBSD syscall trap. */
1471                 fprintf(stderr, "syscall: NetBSD/FreeBSD not supported\n");
1472                 return -1;
1473         case 0x91d02027:
1474                 /* Solaris 2.x gettimeofday */
1475                 update_personality(tcp, 1);
1476                 break;
1477         default:
1478 # if defined(SPARC64)
1479                 fprintf(stderr, "syscall: unknown syscall trap %08lx %016lx\n", trap, sparc_regs.tpc);
1480 # else
1481                 fprintf(stderr, "syscall: unknown syscall trap %08lx %08lx\n", trap, sparc_regs.pc);
1482 # endif
1483                 return -1;
1484         }
1485
1486         /* Extract the system call number from the registers. */
1487         if (trap == 0x91d02027)
1488                 scno = 156;
1489         else
1490                 scno = sparc_regs.u_regs[U_REG_G1];
1491         if (scno == 0) {
1492                 scno = sparc_regs.u_regs[U_REG_O0];
1493                 memmove(&sparc_regs.u_regs[U_REG_O0], &sparc_regs.u_regs[U_REG_O1], 7*sizeof(sparc_regs.u_regs[0]));
1494         }
1495 #elif defined(HPPA)
1496         if (upeek(tcp->pid, PT_GR20, &scno) < 0)
1497                 return -1;
1498 #elif defined(SH)
1499         /*
1500          * In the new syscall ABI, the system call number is in R3.
1501          */
1502         if (upeek(tcp->pid, 4*(REG_REG0+3), &scno) < 0)
1503                 return -1;
1504
1505         if (scno < 0) {
1506                 /* Odd as it may seem, a glibc bug has been known to cause
1507                    glibc to issue bogus negative syscall numbers.  So for
1508                    our purposes, make strace print what it *should* have been */
1509                 long correct_scno = (scno & 0xff);
1510                 if (debug_flag)
1511                         fprintf(stderr,
1512                                 "Detected glibc bug: bogus system call"
1513                                 " number = %ld, correcting to %ld\n",
1514                                 scno,
1515                                 correct_scno);
1516                 scno = correct_scno;
1517         }
1518 #elif defined(SH64)
1519         if (upeek(tcp->pid, REG_SYSCALL, &scno) < 0)
1520                 return -1;
1521         scno &= 0xFFFF;
1522 #elif defined(CRISV10) || defined(CRISV32)
1523         if (upeek(tcp->pid, 4*PT_R9, &scno) < 0)
1524                 return -1;
1525 #elif defined(TILE)
1526         unsigned int currpers;
1527         scno = tile_regs.regs[10];
1528 # ifdef __tilepro__
1529         currpers = 1;
1530 # else
1531 #  ifndef PT_FLAGS_COMPAT
1532 #   define PT_FLAGS_COMPAT 0x10000  /* from Linux 3.8 on */
1533 #  endif
1534         if (tile_regs.flags & PT_FLAGS_COMPAT)
1535                 currpers = 1;
1536         else
1537                 currpers = 0;
1538 # endif
1539         update_personality(tcp, currpers);
1540 #elif defined(MICROBLAZE)
1541         if (upeek(tcp->pid, 0, &scno) < 0)
1542                 return -1;
1543 #elif defined(OR1K)
1544         scno = or1k_regs.gpr[11];
1545 #elif defined(METAG)
1546         scno = metag_regs.dx[0][1];     /* syscall number in D1Re0 (D1.0) */
1547 #elif defined(XTENSA)
1548         if (upeek(tcp->pid, SYSCALL_NR, &scno) < 0)
1549                 return -1;
1550 # elif defined(ARC)
1551         scno = arc_regs.scratch.r8;
1552 #endif
1553
1554         tcp->scno = scno;
1555         if (SCNO_IS_VALID(tcp->scno)) {
1556                 tcp->s_ent = &sysent[scno];
1557                 tcp->qual_flg = qual_flags[scno];
1558         } else {
1559                 static const struct_sysent unknown = {
1560                         .nargs = MAX_ARGS,
1561                         .sys_flags = 0,
1562                         .sys_func = printargs,
1563                         .sys_name = "unknown", /* not used */
1564                 };
1565                 tcp->s_ent = &unknown;
1566                 tcp->qual_flg = UNDEFINED_SCNO | QUAL_RAW | DEFAULT_QUAL_FLAGS;
1567         }
1568         return 1;
1569 }
1570
1571 /*
1572  * Cannot rely on __kernel_[u]long_t being defined,
1573  * it is quite a recent feature of <asm/posix_types.h>.
1574  */
1575 #ifdef __kernel_long_t
1576 typedef __kernel_long_t kernel_long_t;
1577 typedef __kernel_ulong_t kernel_ulong_t;
1578 #else
1579 # ifdef X32
1580 typedef long long kernel_long_t;
1581 typedef unsigned long long kernel_ulong_t;
1582 # else
1583 typedef long kernel_long_t;
1584 typedef unsigned long kernel_ulong_t;
1585 # endif
1586 #endif
1587
1588 /*
1589  * Check the syscall return value register value for whether it is
1590  * a negated errno code indicating an error, or a success return value.
1591  */
1592 static inline bool
1593 is_negated_errno(kernel_ulong_t val)
1594 {
1595         /* Linux kernel defines MAX_ERRNO to 4095. */
1596         kernel_ulong_t max = -(kernel_long_t) 4095;
1597
1598 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
1599         if (current_wordsize < sizeof(val)) {
1600                 val = (uint32_t) val;
1601                 max = (uint32_t) max;
1602         }
1603 #elif defined X32
1604         /*
1605          * current_wordsize is 4 even in personality 0 (native X32)
1606          * but truncation _must not_ be done in it.
1607          * can't check current_wordsize here!
1608          */
1609         if (current_personality != 0) {
1610                 val = (uint32_t) val;
1611                 max = (uint32_t) max;
1612         }
1613 #endif
1614
1615         return val >= max;
1616 }
1617
1618 /* Return -1 on error or 1 on success (never 0!) */
1619 static int
1620 get_syscall_args(struct tcb *tcp)
1621 {
1622         int i, nargs;
1623
1624         nargs = tcp->s_ent->nargs;
1625
1626 #if defined(S390) || defined(S390X)
1627         for (i = 0; i < nargs; ++i)
1628                 if (upeek(tcp->pid, i==0 ? PT_ORIGGPR2 : PT_GPR2 + i*sizeof(long), &tcp->u_arg[i]) < 0)
1629                         return -1;
1630 #elif defined(ALPHA)
1631         for (i = 0; i < nargs; ++i)
1632                 if (upeek(tcp->pid, REG_A0+i, &tcp->u_arg[i]) < 0)
1633                         return -1;
1634 #elif defined(IA64)
1635         if (!ia64_ia32mode) {
1636                 unsigned long *out0, cfm, sof, sol;
1637                 long rbs_end;
1638                 /* be backwards compatible with kernel < 2.4.4... */
1639 #               ifndef PT_RBS_END
1640 #                 define PT_RBS_END     PT_AR_BSP
1641 #               endif
1642
1643                 if (upeek(tcp->pid, PT_RBS_END, &rbs_end) < 0)
1644                         return -1;
1645                 if (upeek(tcp->pid, PT_CFM, (long *) &cfm) < 0)
1646                         return -1;
1647
1648                 sof = (cfm >> 0) & 0x7f;
1649                 sol = (cfm >> 7) & 0x7f;
1650                 out0 = ia64_rse_skip_regs((unsigned long *) rbs_end, -sof + sol);
1651
1652                 for (i = 0; i < nargs; ++i) {
1653                         if (umoven(tcp, (unsigned long) ia64_rse_skip_regs(out0, i),
1654                                    sizeof(long), (char *) &tcp->u_arg[i]) < 0)
1655                                 return -1;
1656                 }
1657         } else {
1658                 static const int argreg[MAX_ARGS] = { PT_R11 /* EBX = out0 */,
1659                                                       PT_R9  /* ECX = out1 */,
1660                                                       PT_R10 /* EDX = out2 */,
1661                                                       PT_R14 /* ESI = out3 */,
1662                                                       PT_R15 /* EDI = out4 */,
1663                                                       PT_R13 /* EBP = out5 */};
1664
1665                 for (i = 0; i < nargs; ++i) {
1666                         if (upeek(tcp->pid, argreg[i], &tcp->u_arg[i]) < 0)
1667                                 return -1;
1668                         /* truncate away IVE sign-extension */
1669                         tcp->u_arg[i] &= 0xffffffff;
1670                 }
1671         }
1672 #elif defined LINUX_MIPSN64
1673         (void)i;
1674         (void)nargs;
1675         tcp->u_arg[0] = mips_REG_A0;
1676         tcp->u_arg[1] = mips_REG_A1;
1677         tcp->u_arg[2] = mips_REG_A2;
1678         tcp->u_arg[3] = mips_REG_A3;
1679         tcp->u_arg[4] = mips_REG_A4;
1680         tcp->u_arg[5] = mips_REG_A5;
1681 #elif defined LINUX_MIPSN32
1682         (void)i;
1683         (void)nargs;
1684         tcp->u_arg[0] = tcp->ext_arg[0] = mips_REG_A0;
1685         tcp->u_arg[1] = tcp->ext_arg[1] = mips_REG_A1;
1686         tcp->u_arg[2] = tcp->ext_arg[2] = mips_REG_A2;
1687         tcp->u_arg[3] = tcp->ext_arg[3] = mips_REG_A3;
1688         tcp->u_arg[4] = tcp->ext_arg[4] = mips_REG_A4;
1689         tcp->u_arg[5] = tcp->ext_arg[5] = mips_REG_A5;
1690 #elif defined LINUX_MIPSO32
1691         (void)i;
1692         (void)nargs;
1693         tcp->u_arg[0] = mips_REG_A0;
1694         tcp->u_arg[1] = mips_REG_A1;
1695         tcp->u_arg[2] = mips_REG_A2;
1696         tcp->u_arg[3] = mips_REG_A3;
1697         if (nargs > 4) {
1698                 umoven(tcp, mips_REG_SP + 4 * 4,
1699                        (nargs - 4) * sizeof(tcp->u_arg[0]),
1700                        (char *)(tcp->u_arg + 4));
1701         }
1702 #elif defined(POWERPC)
1703         (void)i;
1704         (void)nargs;
1705         tcp->u_arg[0] = ppc_regs.orig_gpr3;
1706         tcp->u_arg[1] = ppc_regs.gpr[4];
1707         tcp->u_arg[2] = ppc_regs.gpr[5];
1708         tcp->u_arg[3] = ppc_regs.gpr[6];
1709         tcp->u_arg[4] = ppc_regs.gpr[7];
1710         tcp->u_arg[5] = ppc_regs.gpr[8];
1711 #elif defined(SPARC) || defined(SPARC64)
1712         for (i = 0; i < nargs; ++i)
1713                 tcp->u_arg[i] = sparc_regs.u_regs[U_REG_O0 + i];
1714 #elif defined(HPPA)
1715         for (i = 0; i < nargs; ++i)
1716                 if (upeek(tcp->pid, PT_GR26-4*i, &tcp->u_arg[i]) < 0)
1717                         return -1;
1718 #elif defined(ARM) || defined(AARCH64)
1719 # if defined(AARCH64)
1720         if (tcp->currpers == 1)
1721                 for (i = 0; i < nargs; ++i)
1722                         tcp->u_arg[i] = aarch64_regs.regs[i];
1723         else
1724 # endif
1725         for (i = 0; i < nargs; ++i)
1726                 tcp->u_arg[i] = arm_regs.uregs[i];
1727 #elif defined(AVR32)
1728         (void)i;
1729         (void)nargs;
1730         tcp->u_arg[0] = avr32_regs.r12;
1731         tcp->u_arg[1] = avr32_regs.r11;
1732         tcp->u_arg[2] = avr32_regs.r10;
1733         tcp->u_arg[3] = avr32_regs.r9;
1734         tcp->u_arg[4] = avr32_regs.r5;
1735         tcp->u_arg[5] = avr32_regs.r3;
1736 #elif defined(BFIN)
1737         static const int argreg[MAX_ARGS] = { PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5 };
1738
1739         for (i = 0; i < nargs; ++i)
1740                 if (upeek(tcp->pid, argreg[i], &tcp->u_arg[i]) < 0)
1741                         return -1;
1742 #elif defined(SH)
1743         static const int syscall_regs[MAX_ARGS] = {
1744                 4 * (REG_REG0+4), 4 * (REG_REG0+5), 4 * (REG_REG0+6),
1745                 4 * (REG_REG0+7), 4 * (REG_REG0  ), 4 * (REG_REG0+1)
1746         };
1747
1748         for (i = 0; i < nargs; ++i)
1749                 if (upeek(tcp->pid, syscall_regs[i], &tcp->u_arg[i]) < 0)
1750                         return -1;
1751 #elif defined(SH64)
1752         int i;
1753         /* Registers used by SH5 Linux system calls for parameters */
1754         static const int syscall_regs[MAX_ARGS] = { 2, 3, 4, 5, 6, 7 };
1755
1756         for (i = 0; i < nargs; ++i)
1757                 if (upeek(tcp->pid, REG_GENERAL(syscall_regs[i]), &tcp->u_arg[i]) < 0)
1758                         return -1;
1759 #elif defined(I386)
1760         (void)i;
1761         (void)nargs;
1762         tcp->u_arg[0] = i386_regs.ebx;
1763         tcp->u_arg[1] = i386_regs.ecx;
1764         tcp->u_arg[2] = i386_regs.edx;
1765         tcp->u_arg[3] = i386_regs.esi;
1766         tcp->u_arg[4] = i386_regs.edi;
1767         tcp->u_arg[5] = i386_regs.ebp;
1768 #elif defined(X86_64) || defined(X32)
1769         (void)i;
1770         (void)nargs;
1771         if (x86_io.iov_len != sizeof(i386_regs)) {
1772                 /* x86-64 or x32 ABI */
1773                 tcp->u_arg[0] = x86_64_regs.rdi;
1774                 tcp->u_arg[1] = x86_64_regs.rsi;
1775                 tcp->u_arg[2] = x86_64_regs.rdx;
1776                 tcp->u_arg[3] = x86_64_regs.r10;
1777                 tcp->u_arg[4] = x86_64_regs.r8;
1778                 tcp->u_arg[5] = x86_64_regs.r9;
1779 #  ifdef X32
1780                 tcp->ext_arg[0] = x86_64_regs.rdi;
1781                 tcp->ext_arg[1] = x86_64_regs.rsi;
1782                 tcp->ext_arg[2] = x86_64_regs.rdx;
1783                 tcp->ext_arg[3] = x86_64_regs.r10;
1784                 tcp->ext_arg[4] = x86_64_regs.r8;
1785                 tcp->ext_arg[5] = x86_64_regs.r9;
1786 #  endif
1787         } else {
1788                 /* i386 ABI */
1789                 /* Zero-extend from 32 bits */
1790                 /* Use widen_to_long(tcp->u_arg[N]) in syscall handlers
1791                  * if you need to use *sign-extended* parameter.
1792                  */
1793                 tcp->u_arg[0] = (long)(uint32_t)i386_regs.ebx;
1794                 tcp->u_arg[1] = (long)(uint32_t)i386_regs.ecx;
1795                 tcp->u_arg[2] = (long)(uint32_t)i386_regs.edx;
1796                 tcp->u_arg[3] = (long)(uint32_t)i386_regs.esi;
1797                 tcp->u_arg[4] = (long)(uint32_t)i386_regs.edi;
1798                 tcp->u_arg[5] = (long)(uint32_t)i386_regs.ebp;
1799         }
1800 #elif defined(MICROBLAZE)
1801         for (i = 0; i < nargs; ++i)
1802                 if (upeek(tcp->pid, (5 + i) * 4, &tcp->u_arg[i]) < 0)
1803                         return -1;
1804 #elif defined(CRISV10) || defined(CRISV32)
1805         static const int crisregs[MAX_ARGS] = {
1806                 4*PT_ORIG_R10, 4*PT_R11, 4*PT_R12,
1807                 4*PT_R13     , 4*PT_MOF, 4*PT_SRP
1808         };
1809
1810         for (i = 0; i < nargs; ++i)
1811                 if (upeek(tcp->pid, crisregs[i], &tcp->u_arg[i]) < 0)
1812                         return -1;
1813 #elif defined(TILE)
1814         for (i = 0; i < nargs; ++i)
1815                 tcp->u_arg[i] = tile_regs.regs[i];
1816 #elif defined(M68K)
1817         for (i = 0; i < nargs; ++i)
1818                 if (upeek(tcp->pid, (i < 5 ? i : i + 2)*4, &tcp->u_arg[i]) < 0)
1819                         return -1;
1820 #elif defined(OR1K)
1821         (void)nargs;
1822         for (i = 0; i < 6; ++i)
1823                 tcp->u_arg[i] = or1k_regs.gpr[3 + i];
1824 #elif defined(METAG)
1825         for (i = 0; i < nargs; i++)
1826                 /* arguments go backwards from D1Ar1 (D1.3) */
1827                 tcp->u_arg[i] = ((unsigned long *)&metag_regs.dx[3][1])[-i];
1828 #elif defined(XTENSA)
1829         /* arg0: a6, arg1: a3, arg2: a4, arg3: a5, arg4: a8, arg5: a9 */
1830         static const int xtensaregs[MAX_ARGS] = { 6, 3, 4, 5, 8, 9 };
1831         for (i = 0; i < nargs; ++i)
1832                 if (upeek(tcp->pid, REG_A_BASE + xtensaregs[i], &tcp->u_arg[i]) < 0)
1833                         return -1;
1834 # elif defined(ARC)
1835         long *arc_args = &arc_regs.scratch.r0;
1836         for (i = 0; i < nargs; ++i)
1837                 tcp->u_arg[i] = *arc_args--;
1838
1839 #else /* Other architecture (32bits specific) */
1840         for (i = 0; i < nargs; ++i)
1841                 if (upeek(tcp->pid, i*4, &tcp->u_arg[i]) < 0)
1842                         return -1;
1843 #endif
1844         return 1;
1845 }
1846
1847 static int
1848 trace_syscall_entering(struct tcb *tcp)
1849 {
1850         int res, scno_good;
1851
1852         scno_good = res = (get_regs_error ? -1 : get_scno(tcp));
1853         if (res == 0)
1854                 return res;
1855         if (res == 1)
1856                 res = get_syscall_args(tcp);
1857
1858         if (res != 1) {
1859                 printleader(tcp);
1860                 if (scno_good != 1)
1861                         tprints("????" /* anti-trigraph gap */ "(");
1862                 else if (tcp->qual_flg & UNDEFINED_SCNO)
1863                         tprintf("%s(", undefined_scno_name(tcp));
1864                 else
1865                         tprintf("%s(", tcp->s_ent->sys_name);
1866                 /*
1867                  * " <unavailable>" will be added later by the code which
1868                  * detects ptrace errors.
1869                  */
1870                 goto ret;
1871         }
1872
1873         if (   sys_execve == tcp->s_ent->sys_func
1874 # if defined(SPARC) || defined(SPARC64)
1875             || sys_execv == tcp->s_ent->sys_func
1876 # endif
1877            ) {
1878                 hide_log_until_execve = 0;
1879         }
1880
1881 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
1882         while (1) {
1883 # ifdef SYS_socket_subcall
1884                 if (tcp->s_ent->sys_func == sys_socketcall) {
1885                         decode_socket_subcall(tcp);
1886                         break;
1887                 }
1888 # endif
1889 # ifdef SYS_ipc_subcall
1890                 if (tcp->s_ent->sys_func == sys_ipc) {
1891                         decode_ipc_subcall(tcp);
1892                         break;
1893                 }
1894 # endif
1895                 break;
1896         }
1897 #endif
1898
1899         if (!(tcp->qual_flg & QUAL_TRACE)
1900          || (tracing_paths && !pathtrace_match(tcp))
1901         ) {
1902                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
1903                 return 0;
1904         }
1905
1906         tcp->flags &= ~TCB_FILTERED;
1907
1908         if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
1909                 res = 0;
1910                 goto ret;
1911         }
1912
1913 #ifdef USE_LIBUNWIND
1914         if (stack_trace_enabled) {
1915                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
1916                         unwind_capture_stacktrace(tcp);
1917         }
1918 #endif
1919
1920         printleader(tcp);
1921         if (tcp->qual_flg & UNDEFINED_SCNO)
1922                 tprintf("%s(", undefined_scno_name(tcp));
1923         else
1924                 tprintf("%s(", tcp->s_ent->sys_name);
1925         if ((tcp->qual_flg & QUAL_RAW) && tcp->s_ent->sys_func != sys_exit)
1926                 res = printargs(tcp);
1927         else
1928                 res = tcp->s_ent->sys_func(tcp);
1929
1930         fflush(tcp->outf);
1931  ret:
1932         tcp->flags |= TCB_INSYSCALL;
1933         /* Measure the entrance time as late as possible to avoid errors. */
1934         if (Tflag || cflag)
1935                 gettimeofday(&tcp->etime, NULL);
1936         return res;
1937 }
1938
1939 /* Returns:
1940  * 1: ok, continue in trace_syscall_exiting().
1941  * -1: error, trace_syscall_exiting() should print error indicator
1942  *    ("????" etc) and bail out.
1943  */
1944 static int
1945 get_syscall_result(struct tcb *tcp)
1946 {
1947 #if defined ARCH_REGS_FOR_GETREGSET || defined ARCH_REGS_FOR_GETREGS
1948         /* already done by get_regs */
1949 #elif defined(S390) || defined(S390X)
1950         if (upeek(tcp->pid, PT_GPR2, &s390_gpr2) < 0)
1951                 return -1;
1952 #elif defined(BFIN)
1953         if (upeek(tcp->pid, PT_R0, &bfin_r0) < 0)
1954                 return -1;
1955 #elif defined(IA64)
1956 #       define IA64_PSR_IS      ((long)1 << 34)
1957         long psr;
1958         if (upeek(tcp->pid, PT_CR_IPSR, &psr) >= 0)
1959                 ia64_ia32mode = ((psr & IA64_PSR_IS) != 0);
1960         if (upeek(tcp->pid, PT_R8, &ia64_r8) < 0)
1961                 return -1;
1962         if (upeek(tcp->pid, PT_R10, &ia64_r10) < 0)
1963                 return -1;
1964 #elif defined(M68K)
1965         if (upeek(tcp->pid, 4*PT_D0, &m68k_d0) < 0)
1966                 return -1;
1967 #elif defined(ALPHA)
1968         if (upeek(tcp->pid, REG_A3, &alpha_a3) < 0)
1969                 return -1;
1970         if (upeek(tcp->pid, REG_R0, &alpha_r0) < 0)
1971                 return -1;
1972 #elif defined(HPPA)
1973         if (upeek(tcp->pid, PT_GR28, &hppa_r28) < 0)
1974                 return -1;
1975 #elif defined(SH)
1976         /* new syscall ABI returns result in R0 */
1977         if (upeek(tcp->pid, 4*REG_REG0, (long *)&sh_r0) < 0)
1978                 return -1;
1979 #elif defined(SH64)
1980         /* ABI defines result returned in r9 */
1981         if (upeek(tcp->pid, REG_GENERAL(9), (long *)&sh64_r9) < 0)
1982                 return -1;
1983 #elif defined(CRISV10) || defined(CRISV32)
1984         if (upeek(tcp->pid, 4*PT_R10, &cris_r10) < 0)
1985                 return -1;
1986 #elif defined(MICROBLAZE)
1987         if (upeek(tcp->pid, 3 * 4, &microblaze_r3) < 0)
1988                 return -1;
1989 #elif defined(XTENSA)
1990         if (upeek(tcp->pid, REG_A_BASE + 2, &xtensa_a2) < 0)
1991                 return -1;
1992 #else
1993 # error get_syscall_result is not implemented for this architecture
1994 #endif
1995         return 1;
1996 }
1997
1998 /* Returns:
1999  * 1: ok, continue in trace_syscall_exiting().
2000  * -1: error, trace_syscall_exiting() should print error indicator
2001  *    ("????" etc) and bail out.
2002  */
2003 static void
2004 get_error(struct tcb *tcp)
2005 {
2006         int u_error = 0;
2007         int check_errno = 1;
2008         if (tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS) {
2009                 check_errno = 0;
2010         }
2011 #if defined(S390) || defined(S390X)
2012         if (check_errno && is_negated_errno(s390_gpr2)) {
2013                 tcp->u_rval = -1;
2014                 u_error = -s390_gpr2;
2015         }
2016         else {
2017                 tcp->u_rval = s390_gpr2;
2018         }
2019 #elif defined(I386)
2020         if (check_errno && is_negated_errno(i386_regs.eax)) {
2021                 tcp->u_rval = -1;
2022                 u_error = -i386_regs.eax;
2023         }
2024         else {
2025                 tcp->u_rval = i386_regs.eax;
2026         }
2027 #elif defined(X86_64) || defined(X32)
2028         /*
2029          * In X32, return value is 64-bit (llseek uses one).
2030          * Using merely "long rax" would not work.
2031          */
2032         kernel_long_t rax;
2033
2034         if (x86_io.iov_len == sizeof(i386_regs)) {
2035                 /* Sign extend from 32 bits */
2036                 rax = (int32_t) i386_regs.eax;
2037         } else {
2038                 rax = x86_64_regs.rax;
2039         }
2040         if (check_errno && is_negated_errno(rax)) {
2041                 tcp->u_rval = -1;
2042                 u_error = -rax;
2043         }
2044         else {
2045                 tcp->u_rval = rax;
2046 # ifdef X32
2047                 /* tcp->u_rval contains a truncated value */
2048                 tcp->u_lrval = rax;
2049 # endif
2050         }
2051 #elif defined(IA64)
2052         if (ia64_ia32mode) {
2053                 int err;
2054
2055                 err = (int)ia64_r8;
2056                 if (check_errno && is_negated_errno(err)) {
2057                         tcp->u_rval = -1;
2058                         u_error = -err;
2059                 }
2060                 else {
2061                         tcp->u_rval = err;
2062                 }
2063         } else {
2064                 if (check_errno && ia64_r10) {
2065                         tcp->u_rval = -1;
2066                         u_error = ia64_r8;
2067                 } else {
2068                         tcp->u_rval = ia64_r8;
2069                 }
2070         }
2071 #elif defined(MIPS)
2072         if (check_errno && mips_REG_A3) {
2073                 tcp->u_rval = -1;
2074                 u_error = mips_REG_V0;
2075         } else {
2076 # if defined LINUX_MIPSN32
2077                 tcp->u_lrval = mips_REG_V0;
2078 # endif
2079                 tcp->u_rval = mips_REG_V0;
2080         }
2081 #elif defined(POWERPC)
2082         if (check_errno && (ppc_regs.ccr & 0x10000000)) {
2083                 tcp->u_rval = -1;
2084                 u_error = ppc_regs.gpr[3];
2085         }
2086         else {
2087                 tcp->u_rval = ppc_regs.gpr[3];
2088         }
2089 #elif defined(M68K)
2090         if (check_errno && is_negated_errno(m68k_d0)) {
2091                 tcp->u_rval = -1;
2092                 u_error = -m68k_d0;
2093         }
2094         else {
2095                 tcp->u_rval = m68k_d0;
2096         }
2097 #elif defined(ARM) || defined(AARCH64)
2098 # if defined(AARCH64)
2099         if (tcp->currpers == 1) {
2100                 if (check_errno && is_negated_errno(aarch64_regs.regs[0])) {
2101                         tcp->u_rval = -1;
2102                         u_error = -aarch64_regs.regs[0];
2103                 }
2104                 else {
2105                         tcp->u_rval = aarch64_regs.regs[0];
2106                 }
2107         }
2108         else
2109 # endif
2110         {
2111                 if (check_errno && is_negated_errno(arm_regs.ARM_r0)) {
2112                         tcp->u_rval = -1;
2113                         u_error = -arm_regs.ARM_r0;
2114                 }
2115                 else {
2116                         tcp->u_rval = arm_regs.ARM_r0;
2117                 }
2118         }
2119 #elif defined(AVR32)
2120         if (check_errno && avr32_regs.r12 && (unsigned) -avr32_regs.r12 < nerrnos) {
2121                 tcp->u_rval = -1;
2122                 u_error = -avr32_regs.r12;
2123         }
2124         else {
2125                 tcp->u_rval = avr32_regs.r12;
2126         }
2127 #elif defined(BFIN)
2128         if (check_errno && is_negated_errno(bfin_r0)) {
2129                 tcp->u_rval = -1;
2130                 u_error = -bfin_r0;
2131         } else {
2132                 tcp->u_rval = bfin_r0;
2133         }
2134 #elif defined(ALPHA)
2135         if (check_errno && alpha_a3) {
2136                 tcp->u_rval = -1;
2137                 u_error = alpha_r0;
2138         }
2139         else {
2140                 tcp->u_rval = alpha_r0;
2141         }
2142 #elif defined(SPARC)
2143         if (check_errno && sparc_regs.psr & PSR_C) {
2144                 tcp->u_rval = -1;
2145                 u_error = sparc_regs.u_regs[U_REG_O0];
2146         }
2147         else {
2148                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2149         }
2150 #elif defined(SPARC64)
2151         if (check_errno && sparc_regs.tstate & 0x1100000000UL) {
2152                 tcp->u_rval = -1;
2153                 u_error = sparc_regs.u_regs[U_REG_O0];
2154         }
2155         else {
2156                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2157         }
2158 #elif defined(HPPA)
2159         if (check_errno && is_negated_errno(hppa_r28)) {
2160                 tcp->u_rval = -1;
2161                 u_error = -hppa_r28;
2162         }
2163         else {
2164                 tcp->u_rval = hppa_r28;
2165         }
2166 #elif defined(SH)
2167         if (check_errno && is_negated_errno(sh_r0)) {
2168                 tcp->u_rval = -1;
2169                 u_error = -sh_r0;
2170         }
2171         else {
2172                 tcp->u_rval = sh_r0;
2173         }
2174 #elif defined(SH64)
2175         if (check_errno && is_negated_errno(sh64_r9)) {
2176                 tcp->u_rval = -1;
2177                 u_error = -sh64_r9;
2178         }
2179         else {
2180                 tcp->u_rval = sh64_r9;
2181         }
2182 #elif defined(METAG)
2183         /* result pointer in D0Re0 (D0.0) */
2184         if (check_errno && is_negated_errno(metag_regs.dx[0][0])) {
2185                 tcp->u_rval = -1;
2186                 u_error = -metag_regs.dx[0][0];
2187         }
2188         else {
2189                 tcp->u_rval = metag_regs.dx[0][0];
2190         }
2191 #elif defined(CRISV10) || defined(CRISV32)
2192         if (check_errno && cris_r10 && (unsigned) -cris_r10 < nerrnos) {
2193                 tcp->u_rval = -1;
2194                 u_error = -cris_r10;
2195         }
2196         else {
2197                 tcp->u_rval = cris_r10;
2198         }
2199 #elif defined(TILE)
2200         /*
2201          * The standard tile calling convention returns the value (or negative
2202          * errno) in r0, and zero (or positive errno) in r1.
2203          * Until at least kernel 3.8, however, the r1 value is not reflected
2204          * in ptregs at this point, so we use r0 here.
2205          */
2206         if (check_errno && is_negated_errno(tile_regs.regs[0])) {
2207                 tcp->u_rval = -1;
2208                 u_error = -tile_regs.regs[0];
2209         } else {
2210                 tcp->u_rval = tile_regs.regs[0];
2211         }
2212 #elif defined(MICROBLAZE)
2213         if (check_errno && is_negated_errno(microblaze_r3)) {
2214                 tcp->u_rval = -1;
2215                 u_error = -microblaze_r3;
2216         }
2217         else {
2218                 tcp->u_rval = microblaze_r3;
2219         }
2220 #elif defined(OR1K)
2221         if (check_errno && is_negated_errno(or1k_regs.gpr[11])) {
2222                 tcp->u_rval = -1;
2223                 u_error = -or1k_regs.gpr[11];
2224         }
2225         else {
2226                 tcp->u_rval = or1k_regs.gpr[11];
2227         }
2228 #elif defined(XTENSA)
2229         if (check_errno && is_negated_errno(xtensa_a2)) {
2230                 tcp->u_rval = -1;
2231                 u_error = -xtensa_a2;
2232         }
2233         else {
2234                 tcp->u_rval = xtensa_a2;
2235         }
2236 #elif defined(ARC)
2237         if (check_errno && is_negated_errno(arc_regs.scratch.r0)) {
2238                 tcp->u_rval = -1;
2239                 u_error = -arc_regs.scratch.r0;
2240         }
2241         else {
2242                 tcp->u_rval = arc_regs.scratch.r0;
2243         }
2244 #endif
2245         tcp->u_error = u_error;
2246 }
2247
2248 static void
2249 dumpio(struct tcb *tcp)
2250 {
2251         int (*func)();
2252
2253         if (syserror(tcp))
2254                 return;
2255         if ((unsigned long) tcp->u_arg[0] >= num_quals)
2256                 return;
2257         func = tcp->s_ent->sys_func;
2258         if (func == printargs)
2259                 return;
2260         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
2261                 if (func == sys_read ||
2262                     func == sys_pread ||
2263                     func == sys_recv ||
2264                     func == sys_recvfrom) {
2265                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
2266                         return;
2267                 } else if (func == sys_readv) {
2268                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2269                         return;
2270 #if HAVE_SENDMSG
2271                 } else if (func == sys_recvmsg) {
2272                         dumpiov_in_msghdr(tcp, tcp->u_arg[1]);
2273                         return;
2274                 } else if (func == sys_recvmmsg) {
2275                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
2276                         return;
2277 #endif
2278                 }
2279         }
2280         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
2281                 if (func == sys_write ||
2282                     func == sys_pwrite ||
2283                     func == sys_send ||
2284                     func == sys_sendto)
2285                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
2286                 else if (func == sys_writev)
2287                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2288 #if HAVE_SENDMSG
2289                 else if (func == sys_sendmsg)
2290                         dumpiov_in_msghdr(tcp, tcp->u_arg[1]);
2291                 else if (func == sys_sendmmsg)
2292                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
2293 #endif
2294         }
2295 }
2296
2297 static int
2298 trace_syscall_exiting(struct tcb *tcp)
2299 {
2300         int sys_res;
2301         struct timeval tv;
2302         int res;
2303         long u_error;
2304
2305         /* Measure the exit time as early as possible to avoid errors. */
2306         if (Tflag || cflag)
2307                 gettimeofday(&tv, NULL);
2308
2309 #ifdef USE_LIBUNWIND
2310         if (stack_trace_enabled) {
2311                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
2312                         unwind_cache_invalidate(tcp);
2313         }
2314 #endif
2315
2316 #if SUPPORTED_PERSONALITIES > 1
2317         update_personality(tcp, tcp->currpers);
2318 #endif
2319         res = (get_regs_error ? -1 : get_syscall_result(tcp));
2320         if (res == 1) {
2321                 get_error(tcp); /* never fails */
2322                 if (filtered(tcp) || hide_log_until_execve)
2323                         goto ret;
2324         }
2325
2326         if (cflag) {
2327                 count_syscall(tcp, &tv);
2328                 if (cflag == CFLAG_ONLY_STATS) {
2329                         goto ret;
2330                 }
2331         }
2332
2333         /* If not in -ff mode, and printing_tcp != tcp,
2334          * then the log currently does not end with output
2335          * of _our syscall entry_, but with something else.
2336          * We need to say which syscall's return is this.
2337          *
2338          * Forced reprinting via TCB_REPRINT is used only by
2339          * "strace -ff -oLOG test/threaded_execve" corner case.
2340          * It's the only case when -ff mode needs reprinting.
2341          */
2342         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
2343                 tcp->flags &= ~TCB_REPRINT;
2344                 printleader(tcp);
2345                 if (tcp->qual_flg & UNDEFINED_SCNO)
2346                         tprintf("<... %s resumed> ", undefined_scno_name(tcp));
2347                 else
2348                         tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
2349         }
2350         printing_tcp = tcp;
2351
2352         if (res != 1) {
2353                 /* There was error in one of prior ptrace ops */
2354                 tprints(") ");
2355                 tabto();
2356                 tprints("= ? <unavailable>\n");
2357                 line_ended();
2358                 tcp->flags &= ~TCB_INSYSCALL;
2359                 return res;
2360         }
2361
2362         sys_res = 0;
2363         if (tcp->qual_flg & QUAL_RAW) {
2364                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
2365         } else {
2366         /* FIXME: not_failing_only (IOW, option -z) is broken:
2367          * failure of syscall is known only after syscall return.
2368          * Thus we end up with something like this on, say, ENOENT:
2369          *     open("doesnt_exist", O_RDONLY <unfinished ...>
2370          *     {next syscall decode}
2371          * whereas the intended result is that open(...) line
2372          * is not shown at all.
2373          */
2374                 if (not_failing_only && tcp->u_error)
2375                         goto ret;       /* ignore failed syscalls */
2376                 sys_res = tcp->s_ent->sys_func(tcp);
2377         }
2378
2379         tprints(") ");
2380         tabto();
2381         u_error = tcp->u_error;
2382         if (tcp->qual_flg & QUAL_RAW) {
2383                 if (u_error)
2384                         tprintf("= -1 (errno %ld)", u_error);
2385                 else
2386                         tprintf("= %#lx", tcp->u_rval);
2387         }
2388         else if (!(sys_res & RVAL_NONE) && u_error) {
2389                 switch (u_error) {
2390                 /* Blocked signals do not interrupt any syscalls.
2391                  * In this case syscalls don't return ERESTARTfoo codes.
2392                  *
2393                  * Deadly signals set to SIG_DFL interrupt syscalls
2394                  * and kill the process regardless of which of the codes below
2395                  * is returned by the interrupted syscall.
2396                  * In some cases, kernel forces a kernel-generated deadly
2397                  * signal to be unblocked and set to SIG_DFL (and thus cause
2398                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
2399                  * or SIGILL. (The alternative is to leave process spinning
2400                  * forever on the faulty instruction - not useful).
2401                  *
2402                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
2403                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
2404                  * but kernel will always restart them.
2405                  */
2406                 case ERESTARTSYS:
2407                         /* Most common type of signal-interrupted syscall exit code.
2408                          * The system call will be restarted with the same arguments
2409                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
2410                          */
2411                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
2412                         break;
2413                 case ERESTARTNOINTR:
2414                         /* Rare. For example, fork() returns this if interrupted.
2415                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
2416                          */
2417                         tprints("= ? ERESTARTNOINTR (To be restarted)");
2418                         break;
2419                 case ERESTARTNOHAND:
2420                         /* pause(), rt_sigsuspend() etc use this code.
2421                          * SA_RESTART is ignored (assumed not set):
2422                          * syscall won't restart (will return EINTR instead)
2423                          * even after signal with SA_RESTART set. However,
2424                          * after SIG_IGN or SIG_DFL signal it will restart
2425                          * (thus the name "restart only if has no handler").
2426                          */
2427                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
2428                         break;
2429                 case ERESTART_RESTARTBLOCK:
2430                         /* Syscalls like nanosleep(), poll() which can't be
2431                          * restarted with their original arguments use this
2432                          * code. Kernel will execute restart_syscall() instead,
2433                          * which changes arguments before restarting syscall.
2434                          * SA_RESTART is ignored (assumed not set) similarly
2435                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
2436                          * since restart data is saved in "restart block"
2437                          * in task struct, and if signal handler uses a syscall
2438                          * which in turn saves another such restart block,
2439                          * old data is lost and restart becomes impossible)
2440                          */
2441                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
2442                         break;
2443                 default:
2444                         if ((unsigned long) u_error < nerrnos
2445                             && errnoent[u_error])
2446                                 tprintf("= -1 %s (%s)", errnoent[u_error],
2447                                         strerror(u_error));
2448                         else
2449                                 tprintf("= -1 ERRNO_%lu (%s)", u_error,
2450                                         strerror(u_error));
2451                         break;
2452                 }
2453                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2454                         tprintf(" (%s)", tcp->auxstr);
2455         }
2456         else {
2457                 if (sys_res & RVAL_NONE)
2458                         tprints("= ?");
2459                 else {
2460                         switch (sys_res & RVAL_MASK) {
2461                         case RVAL_HEX:
2462 #if SUPPORTED_PERSONALITIES > 1
2463                                 if (current_wordsize < sizeof(long))
2464                                         tprintf("= %#x",
2465                                                 (unsigned int) tcp->u_rval);
2466                                 else
2467 #endif
2468                                         tprintf("= %#lx", tcp->u_rval);
2469                                 break;
2470                         case RVAL_OCTAL:
2471                                 tprintf("= %#lo", tcp->u_rval);
2472                                 break;
2473                         case RVAL_UDECIMAL:
2474                                 tprintf("= %lu", tcp->u_rval);
2475                                 break;
2476                         case RVAL_DECIMAL:
2477                                 tprintf("= %ld", tcp->u_rval);
2478                                 break;
2479                         case RVAL_FD:
2480                                 if (show_fd_path) {
2481                                         tprints("= ");
2482                                         printfd(tcp, tcp->u_rval);
2483                                 }
2484                                 else
2485                                         tprintf("= %ld", tcp->u_rval);
2486                                 break;
2487 #if defined(LINUX_MIPSN32) || defined(X32)
2488                         /*
2489                         case RVAL_LHEX:
2490                                 tprintf("= %#llx", tcp->u_lrval);
2491                                 break;
2492                         case RVAL_LOCTAL:
2493                                 tprintf("= %#llo", tcp->u_lrval);
2494                                 break;
2495                         */
2496                         case RVAL_LUDECIMAL:
2497                                 tprintf("= %llu", tcp->u_lrval);
2498                                 break;
2499                         /*
2500                         case RVAL_LDECIMAL:
2501                                 tprintf("= %lld", tcp->u_lrval);
2502                                 break;
2503                         */
2504 #endif
2505                         default:
2506                                 fprintf(stderr,
2507                                         "invalid rval format\n");
2508                                 break;
2509                         }
2510                 }
2511                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2512                         tprintf(" (%s)", tcp->auxstr);
2513         }
2514         if (Tflag) {
2515                 tv_sub(&tv, &tv, &tcp->etime);
2516                 tprintf(" <%ld.%06ld>",
2517                         (long) tv.tv_sec, (long) tv.tv_usec);
2518         }
2519         tprints("\n");
2520         dumpio(tcp);
2521         line_ended();
2522
2523 #ifdef USE_LIBUNWIND
2524         if (stack_trace_enabled)
2525                 unwind_print_stacktrace(tcp);
2526 #endif
2527
2528  ret:
2529         tcp->flags &= ~TCB_INSYSCALL;
2530         return 0;
2531 }
2532
2533 int
2534 trace_syscall(struct tcb *tcp)
2535 {
2536         return exiting(tcp) ?
2537                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
2538 }