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/user.h>
  36 #include <sys/param.h>
  37
  38 #ifdef HAVE_SYS_REG_H
  39 # include <sys/reg.h>
  40 #elif defined(HAVE_LINUX_PTRACE_H)
  41 # undef PTRACE_SYSCALL
  42 # ifdef HAVE_STRUCT_IA64_FPREG
  43 #  define ia64_fpreg XXX_ia64_fpreg
  44 # endif
  45 # ifdef HAVE_STRUCT_PT_ALL_USER_REGS
  46 #  define pt_all_user_regs XXX_pt_all_user_regs
  47 # endif
  48 # ifdef HAVE_STRUCT_PTRACE_PEEKSIGINFO_ARGS
  49 #  define ptrace_peeksiginfo_args XXX_ptrace_peeksiginfo_args
  50 # endif
  51 # include <linux/ptrace.h>
  52 # undef ptrace_peeksiginfo_args
  53 # undef ia64_fpreg
  54 # undef pt_all_user_regs
  55 #endif
  56
  57 #if defined(SPARC64)
  58 # undef PTRACE_GETREGS
  59 # define PTRACE_GETREGS PTRACE_GETREGS64
  60 # undef PTRACE_SETREGS
  61 # define PTRACE_SETREGS PTRACE_SETREGS64
  62 #endif
  63
  64 #if defined(IA64)
  65 # include <asm/ptrace_offsets.h>
  66 # include <asm/rse.h>
  67 #endif
  68
  69 /* for struct iovec */
  70 #include <sys/uio.h>
  71 /* for NT_PRSTATUS */
  72 #ifdef HAVE_ELF_H
  73 # include <elf.h>
  74 #endif
  75
  76 #if defined(AARCH64)
  77 # include <asm/ptrace.h>
  78 #endif
  79
  80 #if defined(XTENSA)
  81 # include <asm/ptrace.h>
  82 #endif
  83
  84 #ifndef NSIG
  85 # warning: NSIG is not defined, using 32
  86 # define NSIG 32
  87 #endif
  88
  89 #include "syscall.h"
  90
  91 /* Define these shorthand notations to simplify the syscallent files. */
  92 #define TD TRACE_DESC
  93 #define TF TRACE_FILE
  94 #define TI TRACE_IPC
  95 #define TN TRACE_NETWORK
  96 #define TP TRACE_PROCESS
  97 #define TS TRACE_SIGNAL
  98 #define TM TRACE_MEMORY
  99 #define NF SYSCALL_NEVER_FAILS
 100 #define MA MAX_ARGS
 101 #define SI STACKTRACE_INVALIDATE_CACHE
 102 #define SE STACKTRACE_CAPTURE_ON_ENTER
 103
 104 const struct_sysent sysent0[] = {
 105 #include "syscallent.h"
 106 };
 107
 108 #if SUPPORTED_PERSONALITIES > 1
 109 static const struct_sysent sysent1[] = {
 110 # include "syscallent1.h"
 111 };
 112 #endif
 113
 114 #if SUPPORTED_PERSONALITIES > 2
 115 static const struct_sysent sysent2[] = {
 116 # include "syscallent2.h"
 117 };
 118 #endif
 119
 120 /* Now undef them since short defines cause wicked namespace pollution. */
 121 #undef TD
 122 #undef TF
 123 #undef TI
 124 #undef TN
 125 #undef TP
 126 #undef TS
 127 #undef TM
 128 #undef NF
 129 #undef MA
 130 #undef SI
 131 #undef SE
 132
 133 /*
 134  * `ioctlent.h' may be generated from `ioctlent.raw' by the auxiliary
 135  * program `ioctlsort', such that the list is sorted by the `code' field.
 136  * This has the side-effect of resolving the _IO.. macros into
 137  * plain integers, eliminating the need to include here everything
 138  * in "/usr/include".
 139  */
 140
 141 const char *const errnoent0[] = {
 142 #include "errnoent.h"
 143 };
 144 const char *const signalent0[] = {
 145 #include "signalent.h"
 146 };
 147 const struct_ioctlent ioctlent0[] = {
 148 #include "ioctlent.h"
 149 };
 150
 151 #if SUPPORTED_PERSONALITIES > 1
 152 static const char *const errnoent1[] = {
 153 # include "errnoent1.h"
 154 };
 155 static const char *const signalent1[] = {
 156 # include "signalent1.h"
 157 };
 158 static const struct_ioctlent ioctlent1[] = {
 159 # include "ioctlent1.h"
 160 };
 161 #endif
 162
 163 #if SUPPORTED_PERSONALITIES > 2
 164 static const char *const errnoent2[] = {
 165 # include "errnoent2.h"
 166 };
 167 static const char *const signalent2[] = {
 168 # include "signalent2.h"
 169 };
 170 static const struct_ioctlent ioctlent2[] = {
 171 # include "ioctlent2.h"
 172 };
 173 #endif
 174
 175 enum {
 176         nsyscalls0 = ARRAY_SIZE(sysent0)
 177 #if SUPPORTED_PERSONALITIES > 1
 178         , nsyscalls1 = ARRAY_SIZE(sysent1)
 179 # if SUPPORTED_PERSONALITIES > 2
 180         , nsyscalls2 = ARRAY_SIZE(sysent2)
 181 # endif
 182 #endif
 183 };
 184
 185 enum {
 186         nerrnos0 = ARRAY_SIZE(errnoent0)
 187 #if SUPPORTED_PERSONALITIES > 1
 188         , nerrnos1 = ARRAY_SIZE(errnoent1)
 189 # if SUPPORTED_PERSONALITIES > 2
 190         , nerrnos2 = ARRAY_SIZE(errnoent2)
 191 # endif
 192 #endif
 193 };
 194
 195 enum {
 196         nsignals0 = ARRAY_SIZE(signalent0)
 197 #if SUPPORTED_PERSONALITIES > 1
 198         , nsignals1 = ARRAY_SIZE(signalent1)
 199 # if SUPPORTED_PERSONALITIES > 2
 200         , nsignals2 = ARRAY_SIZE(signalent2)
 201 # endif
 202 #endif
 203 };
 204
 205 enum {
 206         nioctlents0 = ARRAY_SIZE(ioctlent0)
 207 #if SUPPORTED_PERSONALITIES > 1
 208         , nioctlents1 = ARRAY_SIZE(ioctlent1)
 209 # if SUPPORTED_PERSONALITIES > 2
 210         , nioctlents2 = ARRAY_SIZE(ioctlent2)
 211 # endif
 212 #endif
 213 };
 214
 215 #if SUPPORTED_PERSONALITIES > 1
 216 const struct_sysent *sysent = sysent0;
 217 const char *const *errnoent = errnoent0;
 218 const char *const *signalent = signalent0;
 219 const struct_ioctlent *ioctlent = ioctlent0;
 220 #endif
 221 unsigned nsyscalls = nsyscalls0;
 222 unsigned nerrnos = nerrnos0;
 223 unsigned nsignals = nsignals0;
 224 unsigned nioctlents = nioctlents0;
 225
 226 unsigned num_quals;
 227 qualbits_t *qual_vec[SUPPORTED_PERSONALITIES];
 228
 229 static const unsigned nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 230         nsyscalls0,
 231 #if SUPPORTED_PERSONALITIES > 1
 232         nsyscalls1,
 233 #endif
 234 #if SUPPORTED_PERSONALITIES > 2
 235         nsyscalls2,
 236 #endif
 237 };
 238 static const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 239         sysent0,
 240 #if SUPPORTED_PERSONALITIES > 1
 241         sysent1,
 242 #endif
 243 #if SUPPORTED_PERSONALITIES > 2
 244         sysent2,
 245 #endif
 246 };
 247
 248 enum {
 249         MAX_NSYSCALLS1 = (nsyscalls0
 250 #if SUPPORTED_PERSONALITIES > 1
 251                         > nsyscalls1 ? nsyscalls0 : nsyscalls1
 252 #endif
 253                         ),
 254         MAX_NSYSCALLS2 = (MAX_NSYSCALLS1
 255 #if SUPPORTED_PERSONALITIES > 2
 256                         > nsyscalls2 ? MAX_NSYSCALLS1 : nsyscalls2
 257 #endif
 258                         ),
 259         MAX_NSYSCALLS = MAX_NSYSCALLS2,
 260         /* We are ready for arches with up to 255 signals,
 261          * even though the largest known signo is on MIPS and it is 128.
 262          * The number of existing syscalls on all arches is
 263          * larger that 255 anyway, so it is just a pedantic matter.
 264          */
 265         MIN_QUALS = MAX_NSYSCALLS > 255 ? MAX_NSYSCALLS : 255
 266 };
 267
 268 #if SUPPORTED_PERSONALITIES > 1
 269 unsigned current_personality;
 270
 271 # ifndef current_wordsize
 272 unsigned current_wordsize;
 273 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 274         PERSONALITY0_WORDSIZE,
 275         PERSONALITY1_WORDSIZE,
 276 # if SUPPORTED_PERSONALITIES > 2
 277         PERSONALITY2_WORDSIZE,
 278 # endif
 279 };
 280 # endif
 281
 282 void
 283 set_personality(int personality)
 284 {
 285         nsyscalls = nsyscall_vec[personality];
 286         sysent = sysent_vec[personality];
 287
 288         switch (personality) {
 289         case 0:
 290                 errnoent = errnoent0;
 291                 nerrnos = nerrnos0;
 292                 ioctlent = ioctlent0;
 293                 nioctlents = nioctlents0;
 294                 signalent = signalent0;
 295                 nsignals = nsignals0;
 296                 break;
 297
 298         case 1:
 299                 errnoent = errnoent1;
 300                 nerrnos = nerrnos1;
 301                 ioctlent = ioctlent1;
 302                 nioctlents = nioctlents1;
 303                 signalent = signalent1;
 304                 nsignals = nsignals1;
 305                 break;
 306
 307 # if SUPPORTED_PERSONALITIES > 2
 308         case 2:
 309                 errnoent = errnoent2;
 310                 nerrnos = nerrnos2;
 311                 ioctlent = ioctlent2;
 312                 nioctlents = nioctlents2;
 313                 signalent = signalent2;
 314                 nsignals = nsignals2;
 315                 break;
 316 # endif
 317         }
 318
 319         current_personality = personality;
 320 # ifndef current_wordsize
 321         current_wordsize = personality_wordsize[personality];
 322 # endif
 323 }
 324
 325 static void
 326 update_personality(struct tcb *tcp, unsigned int personality)
 327 {
 328         if (personality == current_personality)
 329                 return;
 330         set_personality(personality);
 331
 332         if (personality == tcp->currpers)
 333                 return;
 334         tcp->currpers = personality;
 335
 336 # if defined(POWERPC64)
 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 # elif defined(X86_64)
 343         if (!qflag) {
 344                 static const char *const names[] = {"64 bit", "32 bit", "x32"};
 345                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 346                         tcp->pid, names[personality]);
 347         }
 348 # elif defined(X32)
 349         if (!qflag) {
 350                 static const char *const names[] = {"x32", "32 bit"};
 351                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 352                         tcp->pid, names[personality]);
 353         }
 354 # elif defined(AARCH64)
 355         if (!qflag) {
 356                 static const char *const names[] = {"32-bit", "AArch64"};
 357                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 358                         tcp->pid, names[personality]);
 359         }
 360 # elif defined(TILE)
 361         if (!qflag) {
 362                 static const char *const names[] = {"64-bit", "32-bit"};
 363                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 364                         tcp->pid, names[personality]);
 365         }
 366 # endif
 367 }
 368 #endif
 369
 370 static int qual_syscall(), qual_signal(), qual_desc();
 371
 372 static const struct qual_options {
 373         unsigned int bitflag;
 374         const char *option_name;
 375         int (*qualify)(const char *, int, int);
 376         const char *argument_name;
 377 } qual_options[] = {
 378         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
 379         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
 380         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
 381         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
 382         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
 383         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
 384         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
 385         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
 386         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
 387         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
 388         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
 389         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
 390         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
 391         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
 392         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
 393         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
 394         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
 395         { 0,            NULL,           NULL,           NULL            },
 396 };
 397
 398 static void
 399 reallocate_qual(const unsigned int n)
 400 {
 401         unsigned p;
 402         qualbits_t *qp;
 403         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 404                 qp = qual_vec[p] = realloc(qual_vec[p], n * sizeof(qualbits_t));
 405                 if (!qp)
 406                         die_out_of_memory();
 407                 memset(&qp[num_quals], 0, (n - num_quals) * sizeof(qualbits_t));
 408         }
 409         num_quals = n;
 410 }
 411
 412 static void
 413 qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
 414 {
 415         int p;
 416
 417         if (num_quals <= n)
 418                 reallocate_qual(n + 1);
 419
 420         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 421                 if (pers == p || pers < 0) {
 422                         if (not)
 423                                 qual_vec[p][n] &= ~bitflag;
 424                         else
 425                                 qual_vec[p][n] |= bitflag;
 426                 }
 427         }
 428 }
 429
 430 static int
 431 qual_syscall(const char *s, const unsigned int bitflag, const int not)
 432 {
 433         int p;
 434         unsigned int i;
 435         int rc = -1;
 436
 437         if (*s >= '0' && *s <= '9') {
 438                 i = string_to_uint(s);
 439                 if (i >= MAX_NSYSCALLS)
 440                         return -1;
 441                 qualify_one(i, bitflag, not, -1);
 442                 return 0;
 443         }
 444
 445         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 446                 for (i = 0; i < nsyscall_vec[p]; i++) {
 447                         if (sysent_vec[p][i].sys_name
 448                          && strcmp(s, sysent_vec[p][i].sys_name) == 0
 449                         ) {
 450                                 qualify_one(i, bitflag, not, p);
 451                                 rc = 0;
 452                         }
 453                 }
 454         }
 455
 456         return rc;
 457 }
 458
 459 static int
 460 qual_signal(const char *s, const unsigned int bitflag, const int not)
 461 {
 462         unsigned int i;
 463
 464         if (*s >= '0' && *s <= '9') {
 465                 int signo = string_to_uint(s);
 466                 if (signo < 0 || signo > 255)
 467                         return -1;
 468                 qualify_one(signo, bitflag, not, -1);
 469                 return 0;
 470         }
 471         if (strncasecmp(s, "SIG", 3) == 0)
 472                 s += 3;
 473         for (i = 0; i <= NSIG; i++) {
 474                 if (strcasecmp(s, signame(i) + 3) == 0) {
 475                         qualify_one(i, bitflag, not, -1);
 476                         return 0;
 477                 }
 478         }
 479         return -1;
 480 }
 481
 482 static int
 483 qual_desc(const char *s, const unsigned int bitflag, const int not)
 484 {
 485         if (*s >= '0' && *s <= '9') {
 486                 int desc = string_to_uint(s);
 487                 if (desc < 0 || desc > 0x7fff) /* paranoia */
 488                         return -1;
 489                 qualify_one(desc, bitflag, not, -1);
 490                 return 0;
 491         }
 492         return -1;
 493 }
 494
 495 static int
 496 lookup_class(const char *s)
 497 {
 498         if (strcmp(s, "file") == 0)
 499                 return TRACE_FILE;
 500         if (strcmp(s, "ipc") == 0)
 501                 return TRACE_IPC;
 502         if (strcmp(s, "network") == 0)
 503                 return TRACE_NETWORK;
 504         if (strcmp(s, "process") == 0)
 505                 return TRACE_PROCESS;
 506         if (strcmp(s, "signal") == 0)
 507                 return TRACE_SIGNAL;
 508         if (strcmp(s, "desc") == 0)
 509                 return TRACE_DESC;
 510         if (strcmp(s, "memory") == 0)
 511                 return TRACE_MEMORY;
 512         return -1;
 513 }
 514
 515 void
 516 qualify(const char *s)
 517 {
 518         const struct qual_options *opt;
 519         char *copy;
 520         const char *p;
 521         int not;
 522         unsigned int i;
 523
 524         if (num_quals == 0)
 525                 reallocate_qual(MIN_QUALS);
 526
 527         opt = &qual_options[0];
 528         for (i = 0; (p = qual_options[i].option_name); i++) {
 529                 unsigned int len = strlen(p);
 530                 if (strncmp(s, p, len) == 0 && s[len] == '=') {
 531                         opt = &qual_options[i];
 532                         s += len + 1;
 533                         break;
 534                 }
 535         }
 536         not = 0;
 537         if (*s == '!') {
 538                 not = 1;
 539                 s++;
 540         }
 541         if (strcmp(s, "none") == 0) {
 542                 not = 1 - not;
 543                 s = "all";
 544         }
 545         if (strcmp(s, "all") == 0) {
 546                 for (i = 0; i < num_quals; i++) {
 547                         qualify_one(i, opt->bitflag, not, -1);
 548                 }
 549                 return;
 550         }
 551         for (i = 0; i < num_quals; i++) {
 552                 qualify_one(i, opt->bitflag, !not, -1);
 553         }
 554         copy = strdup(s);
 555         if (!copy)
 556                 die_out_of_memory();
 557         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
 558                 int n;
 559                 if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
 560                         unsigned pers;
 561                         for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
 562                                 for (i = 0; i < nsyscall_vec[pers]; i++)
 563                                         if (sysent_vec[pers][i].sys_flags & n)
 564                                                 qualify_one(i, opt->bitflag, not, pers);
 565                         }
 566                         continue;
 567                 }
 568                 if (opt->qualify(p, opt->bitflag, not)) {
 569                         error_msg_and_die("invalid %s '%s'",
 570                                 opt->argument_name, p);
 571                 }
 572         }
 573         free(copy);
 574         return;
 575 }
 576
 577 #ifdef SYS_socket_subcall
 578 static void
 579 decode_socket_subcall(struct tcb *tcp)
 580 {
 581         unsigned long addr;
 582         unsigned int i, n, size;
 583
 584         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_socket_nsubcalls)
 585                 return;
 586
 587         tcp->scno = SYS_socket_subcall + tcp->u_arg[0];
 588         tcp->qual_flg = qual_flags[tcp->scno];
 589         tcp->s_ent = &sysent[tcp->scno];
 590         addr = tcp->u_arg[1];
 591         size = current_wordsize;
 592         n = tcp->s_ent->nargs;
 593         for (i = 0; i < n; ++i) {
 594                 if (size == sizeof(int)) {
 595                         unsigned int arg;
 596                         if (umove(tcp, addr, &arg) < 0)
 597                                 arg = 0;
 598                         tcp->u_arg[i] = arg;
 599                 }
 600                 else {
 601                         unsigned long arg;
 602                         if (umove(tcp, addr, &arg) < 0)
 603                                 arg = 0;
 604                         tcp->u_arg[i] = arg;
 605                 }
 606                 addr += size;
 607         }
 608 }
 609 #endif
 610
 611 #ifdef SYS_ipc_subcall
 612 static void
 613 decode_ipc_subcall(struct tcb *tcp)
 614 {
 615         unsigned int i, n;
 616
 617         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_ipc_nsubcalls)
 618                 return;
 619
 620         tcp->scno = SYS_ipc_subcall + tcp->u_arg[0];
 621         tcp->qual_flg = qual_flags[tcp->scno];
 622         tcp->s_ent = &sysent[tcp->scno];
 623         n = tcp->s_ent->nargs;
 624         for (i = 0; i < n; i++)
 625                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 626 }
 627 #endif
 628
 629 int
 630 printargs(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%#lx", i ? ", " : "", tcp->u_arg[i]);
 637         }
 638         return 0;
 639 }
 640
 641 int
 642 printargs_lu(struct tcb *tcp)
 643 {
 644         if (entering(tcp)) {
 645                 int i;
 646                 int n = tcp->s_ent->nargs;
 647                 for (i = 0; i < n; i++)
 648                         tprintf("%s%lu", i ? ", " : "", tcp->u_arg[i]);
 649         }
 650         return 0;
 651 }
 652
 653 int
 654 printargs_ld(struct tcb *tcp)
 655 {
 656         if (entering(tcp)) {
 657                 int i;
 658                 int n = tcp->s_ent->nargs;
 659                 for (i = 0; i < n; i++)
 660                         tprintf("%s%ld", i ? ", " : "", tcp->u_arg[i]);
 661         }
 662         return 0;
 663 }
 664
 665 #if defined(SPARC) || defined(SPARC64) || defined(IA64) || defined(SH)
 666 long
 667 getrval2(struct tcb *tcp)
 668 {
 669         long val;
 670
 671 # if defined(SPARC) || defined(SPARC64)
 672         val = sparc_regs.u_regs[U_REG_O1];
 673 # elif defined(SH)
 674         if (upeek(tcp->pid, 4*(REG_REG0+1), &val) < 0)
 675                 return -1;
 676 # elif defined(IA64)
 677         if (upeek(tcp->pid, PT_R9, &val) < 0)
 678                 return -1;
 679 # endif
 680
 681         return val;
 682 }
 683 #endif
 684
 685 #if defined(I386)
 686 static struct user_regs_struct i386_regs;
 687 /* Cast suppresses signedness warning (.esp is long, not unsigned long) */
 688 uint32_t *const i386_esp_ptr = (uint32_t*)&i386_regs.esp;
 689 # define ARCH_REGS_FOR_GETREGSET i386_regs
 690 #elif defined(X86_64) || defined(X32)
 691 /*
 692  * On i386, pt_regs and user_regs_struct are the same,
 693  * but on 64 bit x86, user_regs_struct has six more fields:
 694  * fs_base, gs_base, ds, es, fs, gs.
 695  * PTRACE_GETREGS fills them too, so struct pt_regs would overflow.
 696  */
 697 struct i386_user_regs_struct {
 698         uint32_t ebx;
 699         uint32_t ecx;
 700         uint32_t edx;
 701         uint32_t esi;
 702         uint32_t edi;
 703         uint32_t ebp;
 704         uint32_t eax;
 705         uint32_t xds;
 706         uint32_t xes;
 707         uint32_t xfs;
 708         uint32_t xgs;
 709         uint32_t orig_eax;
 710         uint32_t eip;
 711         uint32_t xcs;
 712         uint32_t eflags;
 713         uint32_t esp;
 714         uint32_t xss;
 715 };
 716 static union {
 717         struct user_regs_struct      x86_64_r;
 718         struct i386_user_regs_struct i386_r;
 719 } x86_regs_union;
 720 # define x86_64_regs x86_regs_union.x86_64_r
 721 # define i386_regs   x86_regs_union.i386_r
 722 uint32_t *const i386_esp_ptr = &i386_regs.esp;
 723 static struct iovec x86_io = {
 724         .iov_base = &x86_regs_union
 725 };
 726 #elif defined(IA64)
 727 bool ia64_ia32mode = 0; /* not static */
 728 static long ia64_r8, ia64_r10;
 729 #elif defined(POWERPC)
 730 struct pt_regs ppc_regs;
 731 #elif defined(M68K)
 732 static long m68k_d0;
 733 #elif defined(BFIN)
 734 static long bfin_r0;
 735 #elif defined(ARM)
 736 struct pt_regs arm_regs; /* not static */
 737 # define ARCH_REGS_FOR_GETREGSET arm_regs
 738 #elif defined(AARCH64)
 739 static union {
 740         struct user_pt_regs aarch64_r;
 741         struct arm_pt_regs  arm_r;
 742 } arm_regs_union;
 743 # define aarch64_regs arm_regs_union.aarch64_r
 744 # define arm_regs     arm_regs_union.arm_r
 745 static struct iovec aarch64_io = {
 746         .iov_base = &arm_regs_union
 747 };
 748 #elif defined(ALPHA)
 749 static long alpha_r0;
 750 static long alpha_a3;
 751 #elif defined(AVR32)
 752 static struct pt_regs avr32_regs;
 753 #elif defined(SPARC) || defined(SPARC64)
 754 struct pt_regs sparc_regs; /* not static */
 755 #elif defined(LINUX_MIPSN32)
 756 static long long mips_a3;
 757 static long long mips_r2;
 758 #elif defined(MIPS)
 759 static long mips_a3;
 760 static long mips_r2;
 761 #elif defined(S390) || defined(S390X)
 762 static long s390_gpr2;
 763 #elif defined(HPPA)
 764 static long hppa_r28;
 765 #elif defined(SH)
 766 static long sh_r0;
 767 #elif defined(SH64)
 768 static long sh64_r9;
 769 #elif defined(CRISV10) || defined(CRISV32)
 770 static long cris_r10;
 771 #elif defined(TILE)
 772 struct pt_regs tile_regs;
 773 #elif defined(MICROBLAZE)
 774 static long microblaze_r3;
 775 #elif defined(OR1K)
 776 static struct user_regs_struct or1k_regs;
 777 # define ARCH_REGS_FOR_GETREGSET or1k_regs
 778 #elif defined(METAG)
 779 static struct user_gp_regs metag_regs;
 780 # define ARCH_REGS_FOR_GETREGSET metag_regs
 781 #elif defined(XTENSA)
 782 static long xtensa_a2;
 783 # elif defined(ARC)
 784 static struct user_regs_struct arc_regs;
 785 # define ARCH_REGS_FOR_GETREGSET arc_regs
 786 #endif
 787
 788 void
 789 print_pc(struct tcb *tcp)
 790 {
 791 #define PRINTBADPC tprintf(sizeof(long) == 4 ? "[????????] " : \
 792                            sizeof(long) == 8 ? "[????????????????] " : \
 793                            NULL /* crash */)
 794         if (get_regs_error) {
 795                 PRINTBADPC;
 796                 return;
 797         }
 798 #if defined(I386)
 799         tprintf("[%08lx] ", i386_regs.eip);
 800 #elif defined(S390) || defined(S390X)
 801         long psw;
 802         if (upeek(tcp->pid, PT_PSWADDR, &psw) < 0) {
 803                 PRINTBADPC;
 804                 return;
 805         }
 806 # ifdef S390
 807         tprintf("[%08lx] ", psw);
 808 # elif S390X
 809         tprintf("[%016lx] ", psw);
 810 # endif
 811 #elif defined(X86_64) || defined(X32)
 812         if (x86_io.iov_len == sizeof(i386_regs)) {
 813                 tprintf("[%08x] ", (unsigned) i386_regs.eip);
 814         } else {
 815 # if defined(X86_64)
 816                 tprintf("[%016lx] ", (unsigned long) x86_64_regs.rip);
 817 # elif defined(X32)
 818                 /* Note: this truncates 64-bit rip to 32 bits */
 819                 tprintf("[%08lx] ", (unsigned long) x86_64_regs.rip);
 820 # endif
 821         }
 822 #elif defined(IA64)
 823         long ip;
 824         if (upeek(tcp->pid, PT_B0, &ip) < 0) {
 825                 PRINTBADPC;
 826                 return;
 827         }
 828         tprintf("[%08lx] ", ip);
 829 #elif defined(POWERPC)
 830         long pc = ppc_regs.nip;
 831 # ifdef POWERPC64
 832         tprintf("[%016lx] ", pc);
 833 # else
 834         tprintf("[%08lx] ", pc);
 835 # endif
 836 #elif defined(M68K)
 837         long pc;
 838         if (upeek(tcp->pid, 4*PT_PC, &pc) < 0) {
 839                 tprints("[????????] ");
 840                 return;
 841         }
 842         tprintf("[%08lx] ", pc);
 843 #elif defined(ALPHA)
 844         long pc;
 845         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
 846                 tprints("[????????????????] ");
 847                 return;
 848         }
 849         tprintf("[%08lx] ", pc);
 850 #elif defined(SPARC)
 851         tprintf("[%08lx] ", sparc_regs.pc);
 852 #elif defined(SPARC64)
 853         tprintf("[%08lx] ", sparc_regs.tpc);
 854 #elif defined(HPPA)
 855         long pc;
 856         if (upeek(tcp->pid, PT_IAOQ0, &pc) < 0) {
 857                 tprints("[????????] ");
 858                 return;
 859         }
 860         tprintf("[%08lx] ", pc);
 861 #elif defined(MIPS)
 862         long pc;
 863         if (upeek(tcp->pid, REG_EPC, &pc) < 0) {
 864                 tprints("[????????] ");
 865                 return;
 866         }
 867         tprintf("[%08lx] ", pc);
 868 #elif defined(SH)
 869         long pc;
 870         if (upeek(tcp->pid, 4*REG_PC, &pc) < 0) {
 871                 tprints("[????????] ");
 872                 return;
 873         }
 874         tprintf("[%08lx] ", pc);
 875 #elif defined(SH64)
 876         long pc;
 877         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
 878                 tprints("[????????????????] ");
 879                 return;
 880         }
 881         tprintf("[%08lx] ", pc);
 882 #elif defined(ARM)
 883         tprintf("[%08lx] ", arm_regs.ARM_pc);
 884 #elif defined(AARCH64)
 885         /* tprintf("[%016lx] ", aarch64_regs.regs[???]); */
 886 #elif defined(AVR32)
 887         tprintf("[%08lx] ", avr32_regs.pc);
 888 #elif defined(BFIN)
 889         long pc;
 890         if (upeek(tcp->pid, PT_PC, &pc) < 0) {
 891                 PRINTBADPC;
 892                 return;
 893         }
 894         tprintf("[%08lx] ", pc);
 895 #elif defined(CRISV10)
 896         long pc;
 897         if (upeek(tcp->pid, 4*PT_IRP, &pc) < 0) {
 898                 PRINTBADPC;
 899                 return;
 900         }
 901         tprintf("[%08lx] ", pc);
 902 #elif defined(CRISV32)
 903         long pc;
 904         if (upeek(tcp->pid, 4*PT_ERP, &pc) < 0) {
 905                 PRINTBADPC;
 906                 return;
 907         }
 908         tprintf("[%08lx] ", pc);
 909 #elif defined(TILE)
 910 # ifdef _LP64
 911         tprintf("[%016lx] ", (unsigned long) tile_regs.pc);
 912 # else
 913         tprintf("[%08lx] ", (unsigned long) tile_regs.pc);
 914 # endif
 915 #elif defined(OR1K)
 916         tprintf("[%08lx] ", or1k_regs.pc);
 917 #elif defined(METAG)
 918         tprintf("[%08lx] ", metag_regs.pc);
 919 #elif defined(XTENSA)
 920         long pc;
 921         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
 922                 PRINTBADPC;
 923                 return;
 924         }
 925         tprintf("[%08lx] ", pc);
 926 #elif defined(ARC)
 927         tprintf("[%08lx] ", arc_regs.efa);
 928 #endif /* architecture */
 929 }
 930
 931 /* Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 932  * The shuffling should be reversible: shuffle_scno(shuffle_scno(n)) == n.
 933  */
 934 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
 935 static long
 936 shuffle_scno(unsigned long scno)
 937 {
 938         if (scno <= ARM_LAST_ORDINARY_SYSCALL)
 939                 return scno;
 940
 941         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 942         if (scno == 0x000ffff0)
 943                 return ARM_LAST_ORDINARY_SYSCALL+1;
 944         if (scno == ARM_LAST_ORDINARY_SYSCALL+1)
 945                 return 0x000ffff0;
 946
 947         /* Is it ARM specific syscall?
 948          * Swap with [LAST_ORDINARY+2, LAST_ORDINARY+2 + LAST_SPECIAL] range.
 949          */
 950         if (scno >= 0x000f0000
 951          && scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL
 952         ) {
 953                 return scno - 0x000f0000 + (ARM_LAST_ORDINARY_SYSCALL+2);
 954         }
 955         if (/* scno >= ARM_LAST_ORDINARY_SYSCALL+2 - always true */ 1
 956          && scno <= (ARM_LAST_ORDINARY_SYSCALL+2) + ARM_LAST_SPECIAL_SYSCALL
 957         ) {
 958                 return scno + 0x000f0000 - (ARM_LAST_ORDINARY_SYSCALL+2);
 959         }
 960
 961         return scno;
 962 }
 963 #else
 964 # define shuffle_scno(scno) ((long)(scno))
 965 #endif
 966
 967 static char*
 968 undefined_scno_name(struct tcb *tcp)
 969 {
 970         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
 971
 972         sprintf(buf, "syscall_%lu", shuffle_scno(tcp->scno));
 973         return buf;
 974 }
 975
 976 #ifdef POWERPC
 977 /*
 978  * PTRACE_GETREGS was added to the PowerPC kernel in v2.6.23,
 979  * we provide a slow fallback for old kernels.
 980  */
 981 static int powerpc_getregs_old(pid_t pid)
 982 {
 983         int i;
 984         long r;
 985
 986         if (iflag) {
 987                 r = upeek(pid, sizeof(long) * PT_NIP, (long *)&ppc_regs.nip);
 988                 if (r)
 989                         goto out;
 990         }
 991 #ifdef POWERPC64 /* else we never use it */
 992         r = upeek(pid, sizeof(long) * PT_MSR, (long *)&ppc_regs.msr);
 993         if (r)
 994                 goto out;
 995 #endif
 996         r = upeek(pid, sizeof(long) * PT_CCR, (long *)&ppc_regs.ccr);
 997         if (r)
 998                 goto out;
 999         r = upeek(pid, sizeof(long) * PT_ORIG_R3, (long *)&ppc_regs.orig_gpr3);
1000         if (r)
1001                 goto out;
1002         for (i = 0; i <= 8; i++) {
1003                 r = upeek(pid, sizeof(long) * (PT_R0 + i),
1004                           (long *)&ppc_regs.gpr[i]);
1005                 if (r)
1006                         goto out;
1007         }
1008  out:
1009         return r;
1010 }
1011 #endif
1012
1013 #ifndef get_regs
1014 long get_regs_error;
1015
1016 #if defined(PTRACE_GETREGSET) && defined(NT_PRSTATUS)
1017 static void get_regset(pid_t pid)
1018 {
1019 /* constant iovec */
1020 # if defined(ARM) \
1021   || defined(I386) \
1022   || defined(METAG) \
1023   || defined(OR1K) \
1024   || defined(ARC)
1025         static struct iovec io = {
1026                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1027                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1028         };
1029         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1030
1031 /* variable iovec */
1032 # elif defined(X86_64) || defined(X32)
1033         /* x86_io.iov_base = &x86_regs_union; - already is */
1034         x86_io.iov_len = sizeof(x86_regs_union);
1035         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &x86_io);
1036 # elif defined(AARCH64)
1037         /* aarch64_io.iov_base = &arm_regs_union; - already is */
1038         aarch64_io.iov_len = sizeof(arm_regs_union);
1039         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &aarch64_io);
1040 # else
1041 #  warning both PTRACE_GETREGSET and NT_PRSTATUS are available but not yet used
1042 # endif
1043 }
1044 #endif /* PTRACE_GETREGSET && NT_PRSTATUS */
1045
1046 void
1047 get_regs(pid_t pid)
1048 {
1049 /* PTRACE_GETREGSET only */
1050 # if defined(METAG) || defined(OR1K) || defined(X32) || defined(AARCH64) || defined(ARC)
1051         get_regset(pid);
1052
1053 /* PTRACE_GETREGS only */
1054 # elif defined(AVR32)
1055         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &avr32_regs);
1056 # elif defined(TILE)
1057         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &tile_regs);
1058 # elif defined(SPARC) || defined(SPARC64)
1059         get_regs_error = ptrace(PTRACE_GETREGS, pid, (char *)&sparc_regs, 0);
1060 # elif defined(POWERPC)
1061         static bool old_kernel = 0;
1062         if (old_kernel)
1063                 goto old;
1064         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (long) &ppc_regs);
1065         if (get_regs_error && errno == EIO) {
1066                 old_kernel = 1;
1067  old:
1068                 get_regs_error = powerpc_getregs_old(pid);
1069         }
1070
1071 /* try PTRACE_GETREGSET first, fallback to PTRACE_GETREGS */
1072 # else
1073 #  if defined(PTRACE_GETREGSET) && defined(NT_PRSTATUS)
1074         static int getregset_support;
1075
1076         if (getregset_support >= 0) {
1077                 get_regset(pid);
1078                 if (getregset_support > 0)
1079                         return;
1080                 if (get_regs_error >= 0) {
1081                         getregset_support = 1;
1082                         return;
1083                 }
1084                 if (errno == EPERM || errno == ESRCH)
1085                         return;
1086                 getregset_support = -1;
1087         }
1088 #  endif /* PTRACE_GETREGSET && NT_PRSTATUS */
1089 #  if defined(ARM)
1090         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &arm_regs);
1091 #  elif defined(I386)
1092         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &i386_regs);
1093 #  elif defined(X86_64)
1094         /* Use old method, with unreliable heuristical detection of 32-bitness. */
1095         x86_io.iov_len = sizeof(x86_64_regs);
1096         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &x86_64_regs);
1097         if (!get_regs_error && x86_64_regs.cs == 0x23) {
1098                 x86_io.iov_len = sizeof(i386_regs);
1099                 /*
1100                  * The order is important: i386_regs and x86_64_regs
1101                  * are overlaid in memory!
1102                  */
1103                 i386_regs.ebx = x86_64_regs.rbx;
1104                 i386_regs.ecx = x86_64_regs.rcx;
1105                 i386_regs.edx = x86_64_regs.rdx;
1106                 i386_regs.esi = x86_64_regs.rsi;
1107                 i386_regs.edi = x86_64_regs.rdi;
1108                 i386_regs.ebp = x86_64_regs.rbp;
1109                 i386_regs.eax = x86_64_regs.rax;
1110                 /* i386_regs.xds = x86_64_regs.ds; unused by strace */
1111                 /* i386_regs.xes = x86_64_regs.es; ditto... */
1112                 /* i386_regs.xfs = x86_64_regs.fs; */
1113                 /* i386_regs.xgs = x86_64_regs.gs; */
1114                 i386_regs.orig_eax = x86_64_regs.orig_rax;
1115                 i386_regs.eip = x86_64_regs.rip;
1116                 /* i386_regs.xcs = x86_64_regs.cs; */
1117                 /* i386_regs.eflags = x86_64_regs.eflags; */
1118                 i386_regs.esp = x86_64_regs.rsp;
1119                 /* i386_regs.xss = x86_64_regs.ss; */
1120         }
1121 #  else
1122 #   error unhandled architecture
1123 #  endif /* ARM || I386 || X86_64 */
1124 # endif
1125 }
1126 #endif /* !get_regs */
1127
1128 /* Returns:
1129  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1130  * 1: ok, continue in trace_syscall_entering().
1131  * other: error, trace_syscall_entering() should print error indicator
1132  *    ("????" etc) and bail out.
1133  */
1134 static int
1135 get_scno(struct tcb *tcp)
1136 {
1137         long scno = 0;
1138
1139 #if defined(S390) || defined(S390X)
1140         if (upeek(tcp->pid, PT_GPR2, &s390_gpr2) < 0)
1141                 return -1;
1142
1143         if (s390_gpr2 != -ENOSYS) {
1144                 /*
1145                  * Since kernel version 2.5.44 the scno gets passed in gpr2.
1146                  */
1147                 scno = s390_gpr2;
1148         } else {
1149                 /*
1150                  * Old style of "passing" the scno via the SVC instruction.
1151                  */
1152                 long psw;
1153                 long opcode, offset_reg, tmp;
1154                 void *svc_addr;
1155                 static const int gpr_offset[16] = {
1156                                 PT_GPR0,  PT_GPR1,  PT_ORIGGPR2, PT_GPR3,
1157                                 PT_GPR4,  PT_GPR5,  PT_GPR6,     PT_GPR7,
1158                                 PT_GPR8,  PT_GPR9,  PT_GPR10,    PT_GPR11,
1159                                 PT_GPR12, PT_GPR13, PT_GPR14,    PT_GPR15
1160                 };
1161
1162                 if (upeek(tcp->pid, PT_PSWADDR, &psw) < 0)
1163                         return -1;
1164                 errno = 0;
1165                 opcode = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)(psw - sizeof(long)), 0);
1166                 if (errno) {
1167                         perror_msg("peektext(psw-oneword)");
1168                         return -1;
1169                 }
1170
1171                 /*
1172                  *  We have to check if the SVC got executed directly or via an
1173                  *  EXECUTE instruction. In case of EXECUTE it is necessary to do
1174                  *  instruction decoding to derive the system call number.
1175                  *  Unfortunately the opcode sizes of EXECUTE and SVC are differently,
1176                  *  so that this doesn't work if a SVC opcode is part of an EXECUTE
1177                  *  opcode. Since there is no way to find out the opcode size this
1178                  *  is the best we can do...
1179                  */
1180                 if ((opcode & 0xff00) == 0x0a00) {
1181                         /* SVC opcode */
1182                         scno = opcode & 0xff;
1183                 }
1184                 else {
1185                         /* SVC got executed by EXECUTE instruction */
1186
1187                         /*
1188                          *  Do instruction decoding of EXECUTE. If you really want to
1189                          *  understand this, read the Principles of Operations.
1190                          */
1191                         svc_addr = (void *) (opcode & 0xfff);
1192
1193                         tmp = 0;
1194                         offset_reg = (opcode & 0x000f0000) >> 16;
1195                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1196                                 return -1;
1197                         svc_addr += tmp;
1198
1199                         tmp = 0;
1200                         offset_reg = (opcode & 0x0000f000) >> 12;
1201                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1202                                 return -1;
1203                         svc_addr += tmp;
1204
1205                         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, svc_addr, 0);
1206                         if (errno)
1207                                 return -1;
1208 # if defined(S390X)
1209                         scno >>= 48;
1210 # else
1211                         scno >>= 16;
1212 # endif
1213                         tmp = 0;
1214                         offset_reg = (opcode & 0x00f00000) >> 20;
1215                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1216                                 return -1;
1217
1218                         scno = (scno | tmp) & 0xff;
1219                 }
1220         }
1221 #elif defined(POWERPC)
1222         scno = ppc_regs.gpr[0];
1223 # ifdef POWERPC64
1224         unsigned int currpers;
1225
1226         /*
1227          * Check for 64/32 bit mode.
1228          * Embedded implementations covered by Book E extension of PPC use
1229          * bit 0 (CM) of 32-bit Machine state register (MSR).
1230          * Other implementations use bit 0 (SF) of 64-bit MSR.
1231          */
1232         currpers = (ppc_regs.msr & 0x8000000080000000) ? 0 : 1;
1233         update_personality(tcp, currpers);
1234 # endif
1235 #elif defined(AVR32)
1236         scno = avr32_regs.r8;
1237 #elif defined(BFIN)
1238         if (upeek(tcp->pid, PT_ORIG_P0, &scno))
1239                 return -1;
1240 #elif defined(I386)
1241         scno = i386_regs.orig_eax;
1242 #elif defined(X86_64) || defined(X32)
1243 # ifndef __X32_SYSCALL_BIT
1244 #  define __X32_SYSCALL_BIT     0x40000000
1245 # endif
1246         unsigned int currpers;
1247 # if 1
1248         /* GETREGSET of NT_PRSTATUS tells us regset size,
1249          * which unambiguously detects i386.
1250          *
1251          * Linux kernel distinguishes x86-64 and x32 processes
1252          * solely by looking at __X32_SYSCALL_BIT:
1253          * arch/x86/include/asm/compat.h::is_x32_task():
1254          * if (task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT)
1255          *         return true;
1256          */
1257         if (x86_io.iov_len == sizeof(i386_regs)) {
1258                 scno = i386_regs.orig_eax;
1259                 currpers = 1;
1260         } else {
1261                 scno = x86_64_regs.orig_rax;
1262                 currpers = 0;
1263                 if (scno & __X32_SYSCALL_BIT) {
1264                         scno -= __X32_SYSCALL_BIT;
1265                         currpers = 2;
1266                 }
1267         }
1268 # elif 0
1269         /* cs = 0x33 for long mode (native 64 bit and x32)
1270          * cs = 0x23 for compatibility mode (32 bit)
1271          * ds = 0x2b for x32 mode (x86-64 in 32 bit)
1272          */
1273         scno = x86_64_regs.orig_rax;
1274         switch (x86_64_regs.cs) {
1275                 case 0x23: currpers = 1; break;
1276                 case 0x33:
1277                         if (x86_64_regs.ds == 0x2b) {
1278                                 currpers = 2;
1279                                 scno &= ~__X32_SYSCALL_BIT;
1280                         } else
1281                                 currpers = 0;
1282                         break;
1283                 default:
1284                         fprintf(stderr, "Unknown value CS=0x%08X while "
1285                                  "detecting personality of process "
1286                                  "PID=%d\n", (int)x86_64_regs.cs, tcp->pid);
1287                         currpers = current_personality;
1288                         break;
1289         }
1290 # elif 0
1291         /* This version analyzes the opcode of a syscall instruction.
1292          * (int 0x80 on i386 vs. syscall on x86-64)
1293          * It works, but is too complicated, and strictly speaking, unreliable.
1294          */
1295         unsigned long call, rip = x86_64_regs.rip;
1296         /* sizeof(syscall) == sizeof(int 0x80) == 2 */
1297         rip -= 2;
1298         errno = 0;
1299         call = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)rip, (char *)0);
1300         if (errno)
1301                 fprintf(stderr, "ptrace_peektext failed: %s\n",
1302                                 strerror(errno));
1303         switch (call & 0xffff) {
1304                 /* x86-64: syscall = 0x0f 0x05 */
1305                 case 0x050f: currpers = 0; break;
1306                 /* i386: int 0x80 = 0xcd 0x80 */
1307                 case 0x80cd: currpers = 1; break;
1308                 default:
1309                         currpers = current_personality;
1310                         fprintf(stderr,
1311                                 "Unknown syscall opcode (0x%04X) while "
1312                                 "detecting personality of process "
1313                                 "PID=%d\n", (int)call, tcp->pid);
1314                         break;
1315         }
1316 # endif
1317
1318 # ifdef X32
1319         /* If we are built for a x32 system, then personality 0 is x32
1320          * (not x86_64), and stracing of x86_64 apps is not supported.
1321          * Stracing of i386 apps is still supported.
1322          */
1323         if (currpers == 0) {
1324                 fprintf(stderr, "syscall_%lu(...) in unsupported "
1325                                 "64-bit mode of process PID=%d\n",
1326                         scno, tcp->pid);
1327                 return 0;
1328         }
1329         currpers &= ~2; /* map 2,1 to 0,1 */
1330 # endif
1331         update_personality(tcp, currpers);
1332 #elif defined(IA64)
1333 #       define IA64_PSR_IS      ((long)1 << 34)
1334         long psr;
1335         if (upeek(tcp->pid, PT_CR_IPSR, &psr) >= 0)
1336                 ia64_ia32mode = ((psr & IA64_PSR_IS) != 0);
1337         if (ia64_ia32mode) {
1338                 if (upeek(tcp->pid, PT_R1, &scno) < 0)
1339                         return -1;
1340         } else {
1341                 if (upeek(tcp->pid, PT_R15, &scno) < 0)
1342                         return -1;
1343         }
1344 #elif defined(AARCH64)
1345         switch (aarch64_io.iov_len) {
1346                 case sizeof(aarch64_regs):
1347                         /* We are in 64-bit mode */
1348                         scno = aarch64_regs.regs[8];
1349                         update_personality(tcp, 1);
1350                         break;
1351                 case sizeof(arm_regs):
1352                         /* We are in 32-bit mode */
1353                         /* Note: we don't support OABI, unlike 32-bit ARM build */
1354                         scno = arm_regs.ARM_r7;
1355                         scno = shuffle_scno(scno);
1356                         update_personality(tcp, 0);
1357                         break;
1358         }
1359 #elif defined(ARM)
1360         if (arm_regs.ARM_ip != 0) {
1361                 /* It is not a syscall entry */
1362                 fprintf(stderr, "pid %d stray syscall exit\n", tcp->pid);
1363                 tcp->flags |= TCB_INSYSCALL;
1364                 return 0;
1365         }
1366         /* Note: we support only 32-bit CPUs, not 26-bit */
1367
1368 # if !defined(__ARM_EABI__) || ENABLE_ARM_OABI
1369         if (arm_regs.ARM_cpsr & 0x20)
1370                 /* Thumb mode */
1371                 goto scno_in_r7;
1372         /* ARM mode */
1373         /* Check EABI/OABI by examining SVC insn's low 24 bits */
1374         errno = 0;
1375         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(arm_regs.ARM_pc - 4), NULL);
1376         if (errno)
1377                 return -1;
1378         /* EABI syscall convention? */
1379         if (scno != 0xef000000) {
1380                 /* No, it's OABI */
1381                 if ((scno & 0x0ff00000) != 0x0f900000) {
1382                         fprintf(stderr, "pid %d unknown syscall trap 0x%08lx\n",
1383                                 tcp->pid, scno);
1384                         return -1;
1385                 }
1386                 /* Fixup the syscall number */
1387                 scno &= 0x000fffff;
1388         } else {
1389  scno_in_r7:
1390                 scno = arm_regs.ARM_r7;
1391         }
1392 # else /* __ARM_EABI__ || !ENABLE_ARM_OABI */
1393         scno = arm_regs.ARM_r7;
1394 # endif
1395         scno = shuffle_scno(scno);
1396 #elif defined(M68K)
1397         if (upeek(tcp->pid, 4*PT_ORIG_D0, &scno) < 0)
1398                 return -1;
1399 #elif defined(LINUX_MIPSN32)
1400         unsigned long long regs[38];
1401
1402         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
1403                 return -1;
1404         mips_a3 = regs[REG_A3];
1405         mips_r2 = regs[REG_V0];
1406
1407         scno = mips_r2;
1408         if (!SCNO_IN_RANGE(scno)) {
1409                 if (mips_a3 == 0 || mips_a3 == -1) {
1410                         if (debug_flag)
1411                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1412                         return 0;
1413                 }
1414         }
1415 #elif defined(MIPS)
1416         if (upeek(tcp->pid, REG_A3, &mips_a3) < 0)
1417                 return -1;
1418         if (upeek(tcp->pid, REG_V0, &scno) < 0)
1419                 return -1;
1420
1421         if (!SCNO_IN_RANGE(scno)) {
1422                 if (mips_a3 == 0 || mips_a3 == -1) {
1423                         if (debug_flag)
1424                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1425                         return 0;
1426                 }
1427         }
1428 #elif defined(ALPHA)
1429         if (upeek(tcp->pid, REG_A3, &alpha_a3) < 0)
1430                 return -1;
1431         if (upeek(tcp->pid, REG_R0, &scno) < 0)
1432                 return -1;
1433
1434         /*
1435          * Do some sanity checks to figure out if it's
1436          * really a syscall entry
1437          */
1438         if (!SCNO_IN_RANGE(scno)) {
1439                 if (alpha_a3 == 0 || alpha_a3 == -1) {
1440                         if (debug_flag)
1441                                 fprintf(stderr, "stray syscall exit: r0 = %ld\n", scno);
1442                         return 0;
1443                 }
1444         }
1445 #elif defined(SPARC) || defined(SPARC64)
1446         /* Disassemble the syscall trap. */
1447         /* Retrieve the syscall trap instruction. */
1448         unsigned long trap;
1449         errno = 0;
1450 # if defined(SPARC64)
1451         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.tpc, 0);
1452         trap >>= 32;
1453 # else
1454         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.pc, 0);
1455 # endif
1456         if (errno)
1457                 return -1;
1458
1459         /* Disassemble the trap to see what personality to use. */
1460         switch (trap) {
1461         case 0x91d02010:
1462                 /* Linux/SPARC syscall trap. */
1463                 update_personality(tcp, 0);
1464                 break;
1465         case 0x91d0206d:
1466                 /* Linux/SPARC64 syscall trap. */
1467                 update_personality(tcp, 2);
1468                 break;
1469         case 0x91d02000:
1470                 /* SunOS syscall trap. (pers 1) */
1471                 fprintf(stderr, "syscall: SunOS no support\n");
1472                 return -1;
1473         case 0x91d02008:
1474                 /* Solaris 2.x syscall trap. (per 2) */
1475                 update_personality(tcp, 1);
1476                 break;
1477         case 0x91d02009:
1478                 /* NetBSD/FreeBSD syscall trap. */
1479                 fprintf(stderr, "syscall: NetBSD/FreeBSD not supported\n");
1480                 return -1;
1481         case 0x91d02027:
1482                 /* Solaris 2.x gettimeofday */
1483                 update_personality(tcp, 1);
1484                 break;
1485         default:
1486 # if defined(SPARC64)
1487                 fprintf(stderr, "syscall: unknown syscall trap %08lx %016lx\n", trap, sparc_regs.tpc);
1488 # else
1489                 fprintf(stderr, "syscall: unknown syscall trap %08lx %08lx\n", trap, sparc_regs.pc);
1490 # endif
1491                 return -1;
1492         }
1493
1494         /* Extract the system call number from the registers. */
1495         if (trap == 0x91d02027)
1496                 scno = 156;
1497         else
1498                 scno = sparc_regs.u_regs[U_REG_G1];
1499         if (scno == 0) {
1500                 scno = sparc_regs.u_regs[U_REG_O0];
1501                 memmove(&sparc_regs.u_regs[U_REG_O0], &sparc_regs.u_regs[U_REG_O1], 7*sizeof(sparc_regs.u_regs[0]));
1502         }
1503 #elif defined(HPPA)
1504         if (upeek(tcp->pid, PT_GR20, &scno) < 0)
1505                 return -1;
1506 #elif defined(SH)
1507         /*
1508          * In the new syscall ABI, the system call number is in R3.
1509          */
1510         if (upeek(tcp->pid, 4*(REG_REG0+3), &scno) < 0)
1511                 return -1;
1512
1513         if (scno < 0) {
1514                 /* Odd as it may seem, a glibc bug has been known to cause
1515                    glibc to issue bogus negative syscall numbers.  So for
1516                    our purposes, make strace print what it *should* have been */
1517                 long correct_scno = (scno & 0xff);
1518                 if (debug_flag)
1519                         fprintf(stderr,
1520                                 "Detected glibc bug: bogus system call"
1521                                 " number = %ld, correcting to %ld\n",
1522                                 scno,
1523                                 correct_scno);
1524                 scno = correct_scno;
1525         }
1526 #elif defined(SH64)
1527         if (upeek(tcp->pid, REG_SYSCALL, &scno) < 0)
1528                 return -1;
1529         scno &= 0xFFFF;
1530 #elif defined(CRISV10) || defined(CRISV32)
1531         if (upeek(tcp->pid, 4*PT_R9, &scno) < 0)
1532                 return -1;
1533 #elif defined(TILE)
1534         unsigned int currpers;
1535         scno = tile_regs.regs[10];
1536 # ifdef __tilepro__
1537         currpers = 1;
1538 # else
1539 #  ifndef PT_FLAGS_COMPAT
1540 #   define PT_FLAGS_COMPAT 0x10000  /* from Linux 3.8 on */
1541 #  endif
1542         if (tile_regs.flags & PT_FLAGS_COMPAT)
1543                 currpers = 1;
1544         else
1545                 currpers = 0;
1546 # endif
1547         update_personality(tcp, currpers);
1548 #elif defined(MICROBLAZE)
1549         if (upeek(tcp->pid, 0, &scno) < 0)
1550                 return -1;
1551 #elif defined(OR1K)
1552         scno = or1k_regs.gpr[11];
1553 #elif defined(METAG)
1554         scno = metag_regs.dx[0][1];     /* syscall number in D1Re0 (D1.0) */
1555 #elif defined(XTENSA)
1556         if (upeek(tcp->pid, SYSCALL_NR, &scno) < 0)
1557                 return -1;
1558 # elif defined(ARC)
1559         scno = arc_regs.scratch.r8;
1560 #endif
1561
1562         tcp->scno = scno;
1563         if (SCNO_IS_VALID(tcp->scno)) {
1564                 tcp->s_ent = &sysent[scno];
1565                 tcp->qual_flg = qual_flags[scno];
1566         } else {
1567                 static const struct_sysent unknown = {
1568                         .nargs = MAX_ARGS,
1569                         .sys_flags = 0,
1570                         .sys_func = printargs,
1571                         .sys_name = "unknown", /* not used */
1572                 };
1573                 tcp->s_ent = &unknown;
1574                 tcp->qual_flg = UNDEFINED_SCNO | QUAL_RAW | DEFAULT_QUAL_FLAGS;
1575         }
1576         return 1;
1577 }
1578
1579 /* Called at each syscall entry.
1580  * Returns:
1581  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1582  * 1: ok, continue in trace_syscall_entering().
1583  * other: error, trace_syscall_entering() should print error indicator
1584  *    ("????" etc) and bail out.
1585  */
1586 static int
1587 syscall_fixup_on_sysenter(struct tcb *tcp)
1588 {
1589         /* A common case of "not a syscall entry" is post-execve SIGTRAP */
1590 #if defined(I386)
1591         if (i386_regs.eax != -ENOSYS) {
1592                 if (debug_flag)
1593                         fprintf(stderr, "not a syscall entry (eax = %ld)\n", i386_regs.eax);
1594                 return 0;
1595         }
1596 #elif defined(X86_64) || defined(X32)
1597         {
1598                 long rax;
1599                 if (x86_io.iov_len == sizeof(i386_regs)) {
1600                         /* Sign extend from 32 bits */
1601                         rax = (int32_t)i386_regs.eax;
1602                 } else {
1603                         /* Note: in X32 build, this truncates 64 to 32 bits */
1604                         rax = x86_64_regs.rax;
1605                 }
1606                 if (rax != -ENOSYS) {
1607                         if (debug_flag)
1608                                 fprintf(stderr, "not a syscall entry (rax = %ld)\n", rax);
1609                         return 0;
1610                 }
1611         }
1612 #elif defined(M68K)
1613         /* TODO? Eliminate upeek's in arches below like we did in x86 */
1614         if (upeek(tcp->pid, 4*PT_D0, &m68k_d0) < 0)
1615                 return -1;
1616         if (m68k_d0 != -ENOSYS) {
1617                 if (debug_flag)
1618                         fprintf(stderr, "not a syscall entry (d0 = %ld)\n", m68k_d0);
1619                 return 0;
1620         }
1621 #elif defined(IA64)
1622         if (upeek(tcp->pid, PT_R10, &ia64_r10) < 0)
1623                 return -1;
1624         if (upeek(tcp->pid, PT_R8, &ia64_r8) < 0)
1625                 return -1;
1626         if (ia64_ia32mode && ia64_r8 != -ENOSYS) {
1627                 if (debug_flag)
1628                         fprintf(stderr, "not a syscall entry (r8 = %ld)\n", ia64_r8);
1629                 return 0;
1630         }
1631 #elif defined(CRISV10) || defined(CRISV32)
1632         if (upeek(tcp->pid, 4*PT_R10, &cris_r10) < 0)
1633                 return -1;
1634         if (cris_r10 != -ENOSYS) {
1635                 if (debug_flag)
1636                         fprintf(stderr, "not a syscall entry (r10 = %ld)\n", cris_r10);
1637                 return 0;
1638         }
1639 #elif defined(MICROBLAZE)
1640         if (upeek(tcp->pid, 3 * 4, &microblaze_r3) < 0)
1641                 return -1;
1642         if (microblaze_r3 != -ENOSYS) {
1643                 if (debug_flag)
1644                         fprintf(stderr, "not a syscall entry (r3 = %ld)\n", microblaze_r3);
1645                 return 0;
1646         }
1647 #endif
1648         return 1;
1649 }
1650
1651 static void
1652 internal_fork(struct tcb *tcp)
1653 {
1654 #if defined S390 || defined S390X || defined CRISV10 || defined CRISV32
1655 # define ARG_FLAGS      1
1656 #else
1657 # define ARG_FLAGS      0
1658 #endif
1659 #ifndef CLONE_UNTRACED
1660 # define CLONE_UNTRACED 0x00800000
1661 #endif
1662         if ((ptrace_setoptions
1663             & (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
1664            == (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
1665                 return;
1666
1667         if (!followfork)
1668                 return;
1669
1670         if (entering(tcp)) {
1671                 /*
1672                  * We won't see the new child if clone is called with
1673                  * CLONE_UNTRACED, so we keep the same logic with that option
1674                  * and don't trace it.
1675                  */
1676                 if ((tcp->s_ent->sys_func == sys_clone)
1677                  && (tcp->u_arg[ARG_FLAGS] & CLONE_UNTRACED)
1678                 )
1679                         return;
1680                 setbpt(tcp);
1681         } else {
1682                 if (tcp->flags & TCB_BPTSET)
1683                         clearbpt(tcp);
1684         }
1685 }
1686
1687 #if defined(TCB_WAITEXECVE)
1688 static void
1689 internal_exec(struct tcb *tcp)
1690 {
1691         /* Maybe we have post-execve SIGTRAP suppressed? */
1692         if (ptrace_setoptions & PTRACE_O_TRACEEXEC)
1693                 return; /* yes, no need to do anything */
1694
1695         if (exiting(tcp) && syserror(tcp))
1696                 /* Error in execve, no post-execve SIGTRAP expected */
1697                 tcp->flags &= ~TCB_WAITEXECVE;
1698         else
1699                 tcp->flags |= TCB_WAITEXECVE;
1700 }
1701 #endif
1702
1703 static void
1704 syscall_fixup_for_fork_exec(struct tcb *tcp)
1705 {
1706         /*
1707          * We must always trace a few critical system calls in order to
1708          * correctly support following forks in the presence of tracing
1709          * qualifiers.
1710          */
1711         int (*func)();
1712
1713         func = tcp->s_ent->sys_func;
1714
1715         if (   sys_fork == func
1716             || sys_clone == func
1717            ) {
1718                 internal_fork(tcp);
1719                 return;
1720         }
1721
1722 #if defined(TCB_WAITEXECVE)
1723         if (   sys_execve == func
1724 # if defined(SPARC) || defined(SPARC64)
1725             || sys_execv == func
1726 # endif
1727            ) {
1728                 internal_exec(tcp);
1729                 return;
1730         }
1731 #endif
1732 }
1733
1734 /* Return -1 on error or 1 on success (never 0!) */
1735 static int
1736 get_syscall_args(struct tcb *tcp)
1737 {
1738         int i, nargs;
1739
1740         nargs = tcp->s_ent->nargs;
1741
1742 #if defined(S390) || defined(S390X)
1743         for (i = 0; i < nargs; ++i)
1744                 if (upeek(tcp->pid, i==0 ? PT_ORIGGPR2 : PT_GPR2 + i*sizeof(long), &tcp->u_arg[i]) < 0)
1745                         return -1;
1746 #elif defined(ALPHA)
1747         for (i = 0; i < nargs; ++i)
1748                 if (upeek(tcp->pid, REG_A0+i, &tcp->u_arg[i]) < 0)
1749                         return -1;
1750 #elif defined(IA64)
1751         if (!ia64_ia32mode) {
1752                 unsigned long *out0, cfm, sof, sol;
1753                 long rbs_end;
1754                 /* be backwards compatible with kernel < 2.4.4... */
1755 #               ifndef PT_RBS_END
1756 #                 define PT_RBS_END     PT_AR_BSP
1757 #               endif
1758
1759                 if (upeek(tcp->pid, PT_RBS_END, &rbs_end) < 0)
1760                         return -1;
1761                 if (upeek(tcp->pid, PT_CFM, (long *) &cfm) < 0)
1762                         return -1;
1763
1764                 sof = (cfm >> 0) & 0x7f;
1765                 sol = (cfm >> 7) & 0x7f;
1766                 out0 = ia64_rse_skip_regs((unsigned long *) rbs_end, -sof + sol);
1767
1768                 for (i = 0; i < nargs; ++i) {
1769                         if (umoven(tcp, (unsigned long) ia64_rse_skip_regs(out0, i),
1770                                    sizeof(long), (char *) &tcp->u_arg[i]) < 0)
1771                                 return -1;
1772                 }
1773         } else {
1774                 static const int argreg[MAX_ARGS] = { PT_R11 /* EBX = out0 */,
1775                                                       PT_R9  /* ECX = out1 */,
1776                                                       PT_R10 /* EDX = out2 */,
1777                                                       PT_R14 /* ESI = out3 */,
1778                                                       PT_R15 /* EDI = out4 */,
1779                                                       PT_R13 /* EBP = out5 */};
1780
1781                 for (i = 0; i < nargs; ++i) {
1782                         if (upeek(tcp->pid, argreg[i], &tcp->u_arg[i]) < 0)
1783                                 return -1;
1784                         /* truncate away IVE sign-extension */
1785                         tcp->u_arg[i] &= 0xffffffff;
1786                 }
1787         }
1788 #elif defined(LINUX_MIPSN32) || defined(LINUX_MIPSN64)
1789         /* N32 and N64 both use up to six registers.  */
1790         unsigned long long regs[38];
1791
1792         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
1793                 return -1;
1794
1795         for (i = 0; i < nargs; ++i) {
1796                 tcp->u_arg[i] = regs[REG_A0 + i];
1797 # if defined(LINUX_MIPSN32)
1798                 tcp->ext_arg[i] = regs[REG_A0 + i];
1799 # endif
1800         }
1801 #elif defined(MIPS)
1802         if (nargs > 4) {
1803                 long sp;
1804
1805                 if (upeek(tcp->pid, REG_SP, &sp) < 0)
1806                         return -1;
1807                 for (i = 0; i < 4; ++i)
1808                         if (upeek(tcp->pid, REG_A0 + i, &tcp->u_arg[i]) < 0)
1809                                 return -1;
1810                 umoven(tcp, sp + 16, (nargs - 4) * sizeof(tcp->u_arg[0]),
1811                        (char *)(tcp->u_arg + 4));
1812         } else {
1813                 for (i = 0; i < nargs; ++i)
1814                         if (upeek(tcp->pid, REG_A0 + i, &tcp->u_arg[i]) < 0)
1815                                 return -1;
1816         }
1817 #elif defined(POWERPC)
1818         (void)i;
1819         (void)nargs;
1820         tcp->u_arg[0] = ppc_regs.orig_gpr3;
1821         tcp->u_arg[1] = ppc_regs.gpr[4];
1822         tcp->u_arg[2] = ppc_regs.gpr[5];
1823         tcp->u_arg[3] = ppc_regs.gpr[6];
1824         tcp->u_arg[4] = ppc_regs.gpr[7];
1825         tcp->u_arg[5] = ppc_regs.gpr[8];
1826 #elif defined(SPARC) || defined(SPARC64)
1827         for (i = 0; i < nargs; ++i)
1828                 tcp->u_arg[i] = sparc_regs.u_regs[U_REG_O0 + i];
1829 #elif defined(HPPA)
1830         for (i = 0; i < nargs; ++i)
1831                 if (upeek(tcp->pid, PT_GR26-4*i, &tcp->u_arg[i]) < 0)
1832                         return -1;
1833 #elif defined(ARM) || defined(AARCH64)
1834 # if defined(AARCH64)
1835         if (tcp->currpers == 1)
1836                 for (i = 0; i < nargs; ++i)
1837                         tcp->u_arg[i] = aarch64_regs.regs[i];
1838         else
1839 # endif
1840         for (i = 0; i < nargs; ++i)
1841                 tcp->u_arg[i] = arm_regs.uregs[i];
1842 #elif defined(AVR32)
1843         (void)i;
1844         (void)nargs;
1845         tcp->u_arg[0] = avr32_regs.r12;
1846         tcp->u_arg[1] = avr32_regs.r11;
1847         tcp->u_arg[2] = avr32_regs.r10;
1848         tcp->u_arg[3] = avr32_regs.r9;
1849         tcp->u_arg[4] = avr32_regs.r5;
1850         tcp->u_arg[5] = avr32_regs.r3;
1851 #elif defined(BFIN)
1852         static const int argreg[MAX_ARGS] = { PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5 };
1853
1854         for (i = 0; i < nargs; ++i)
1855                 if (upeek(tcp->pid, argreg[i], &tcp->u_arg[i]) < 0)
1856                         return -1;
1857 #elif defined(SH)
1858         static const int syscall_regs[MAX_ARGS] = {
1859                 4 * (REG_REG0+4), 4 * (REG_REG0+5), 4 * (REG_REG0+6),
1860                 4 * (REG_REG0+7), 4 * (REG_REG0  ), 4 * (REG_REG0+1)
1861         };
1862
1863         for (i = 0; i < nargs; ++i)
1864                 if (upeek(tcp->pid, syscall_regs[i], &tcp->u_arg[i]) < 0)
1865                         return -1;
1866 #elif defined(SH64)
1867         int i;
1868         /* Registers used by SH5 Linux system calls for parameters */
1869         static const int syscall_regs[MAX_ARGS] = { 2, 3, 4, 5, 6, 7 };
1870
1871         for (i = 0; i < nargs; ++i)
1872                 if (upeek(tcp->pid, REG_GENERAL(syscall_regs[i]), &tcp->u_arg[i]) < 0)
1873                         return -1;
1874 #elif defined(I386)
1875         (void)i;
1876         (void)nargs;
1877         tcp->u_arg[0] = i386_regs.ebx;
1878         tcp->u_arg[1] = i386_regs.ecx;
1879         tcp->u_arg[2] = i386_regs.edx;
1880         tcp->u_arg[3] = i386_regs.esi;
1881         tcp->u_arg[4] = i386_regs.edi;
1882         tcp->u_arg[5] = i386_regs.ebp;
1883 #elif defined(X86_64) || defined(X32)
1884         (void)i;
1885         (void)nargs;
1886         if (x86_io.iov_len != sizeof(i386_regs)) {
1887                 /* x86-64 or x32 ABI */
1888                 tcp->u_arg[0] = x86_64_regs.rdi;
1889                 tcp->u_arg[1] = x86_64_regs.rsi;
1890                 tcp->u_arg[2] = x86_64_regs.rdx;
1891                 tcp->u_arg[3] = x86_64_regs.r10;
1892                 tcp->u_arg[4] = x86_64_regs.r8;
1893                 tcp->u_arg[5] = x86_64_regs.r9;
1894 #  ifdef X32
1895                 tcp->ext_arg[0] = x86_64_regs.rdi;
1896                 tcp->ext_arg[1] = x86_64_regs.rsi;
1897                 tcp->ext_arg[2] = x86_64_regs.rdx;
1898                 tcp->ext_arg[3] = x86_64_regs.r10;
1899                 tcp->ext_arg[4] = x86_64_regs.r8;
1900                 tcp->ext_arg[5] = x86_64_regs.r9;
1901 #  endif
1902         } else {
1903                 /* i386 ABI */
1904                 /* Zero-extend from 32 bits */
1905                 /* Use widen_to_long(tcp->u_arg[N]) in syscall handlers
1906                  * if you need to use *sign-extended* parameter.
1907                  */
1908                 tcp->u_arg[0] = (long)(uint32_t)i386_regs.ebx;
1909                 tcp->u_arg[1] = (long)(uint32_t)i386_regs.ecx;
1910                 tcp->u_arg[2] = (long)(uint32_t)i386_regs.edx;
1911                 tcp->u_arg[3] = (long)(uint32_t)i386_regs.esi;
1912                 tcp->u_arg[4] = (long)(uint32_t)i386_regs.edi;
1913                 tcp->u_arg[5] = (long)(uint32_t)i386_regs.ebp;
1914         }
1915 #elif defined(MICROBLAZE)
1916         for (i = 0; i < nargs; ++i)
1917                 if (upeek(tcp->pid, (5 + i) * 4, &tcp->u_arg[i]) < 0)
1918                         return -1;
1919 #elif defined(CRISV10) || defined(CRISV32)
1920         static const int crisregs[MAX_ARGS] = {
1921                 4*PT_ORIG_R10, 4*PT_R11, 4*PT_R12,
1922                 4*PT_R13     , 4*PT_MOF, 4*PT_SRP
1923         };
1924
1925         for (i = 0; i < nargs; ++i)
1926                 if (upeek(tcp->pid, crisregs[i], &tcp->u_arg[i]) < 0)
1927                         return -1;
1928 #elif defined(TILE)
1929         for (i = 0; i < nargs; ++i)
1930                 tcp->u_arg[i] = tile_regs.regs[i];
1931 #elif defined(M68K)
1932         for (i = 0; i < nargs; ++i)
1933                 if (upeek(tcp->pid, (i < 5 ? i : i + 2)*4, &tcp->u_arg[i]) < 0)
1934                         return -1;
1935 #elif defined(OR1K)
1936         (void)nargs;
1937         for (i = 0; i < 6; ++i)
1938                 tcp->u_arg[i] = or1k_regs.gpr[3 + i];
1939 #elif defined(METAG)
1940         for (i = 0; i < nargs; i++)
1941                 /* arguments go backwards from D1Ar1 (D1.3) */
1942                 tcp->u_arg[i] = ((unsigned long *)&metag_regs.dx[3][1])[-i];
1943 #elif defined(XTENSA)
1944         /* arg0: a6, arg1: a3, arg2: a4, arg3: a5, arg4: a8, arg5: a9 */
1945         static const int xtensaregs[MAX_ARGS] = { 6, 3, 4, 5, 8, 9 };
1946         for (i = 0; i < nargs; ++i)
1947                 if (upeek(tcp->pid, REG_A_BASE + xtensaregs[i], &tcp->u_arg[i]) < 0)
1948                         return -1;
1949 # elif defined(ARC)
1950         long *arc_args = &arc_regs.scratch.r0;
1951         for (i = 0; i < nargs; ++i)
1952                 tcp->u_arg[i] = *arc_args--;
1953
1954 #else /* Other architecture (32bits specific) */
1955         for (i = 0; i < nargs; ++i)
1956                 if (upeek(tcp->pid, i*4, &tcp->u_arg[i]) < 0)
1957                         return -1;
1958 #endif
1959         return 1;
1960 }
1961
1962 static int
1963 trace_syscall_entering(struct tcb *tcp)
1964 {
1965         int res, scno_good;
1966
1967 #if defined TCB_WAITEXECVE
1968         if (tcp->flags & TCB_WAITEXECVE) {
1969                 /* This is the post-execve SIGTRAP. */
1970                 tcp->flags &= ~TCB_WAITEXECVE;
1971                 return 0;
1972         }
1973 #endif
1974
1975         scno_good = res = (get_regs_error ? -1 : get_scno(tcp));
1976         if (res == 0)
1977                 return res;
1978         if (res == 1) {
1979                 res = syscall_fixup_on_sysenter(tcp);
1980                 if (res == 0)
1981                         return res;
1982                 if (res == 1)
1983                         res = get_syscall_args(tcp);
1984         }
1985
1986         if (res != 1) {
1987                 printleader(tcp);
1988                 if (scno_good != 1)
1989                         tprints("????" /* anti-trigraph gap */ "(");
1990                 else if (tcp->qual_flg & UNDEFINED_SCNO)
1991                         tprintf("%s(", undefined_scno_name(tcp));
1992                 else
1993                         tprintf("%s(", tcp->s_ent->sys_name);
1994                 /*
1995                  * " <unavailable>" will be added later by the code which
1996                  * detects ptrace errors.
1997                  */
1998                 goto ret;
1999         }
2000
2001         if (   sys_execve == tcp->s_ent->sys_func
2002 # if defined(SPARC) || defined(SPARC64)
2003             || sys_execv == tcp->s_ent->sys_func
2004 # endif
2005            ) {
2006                 hide_log_until_execve = 0;
2007         }
2008
2009 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
2010         while (1) {
2011 # ifdef SYS_socket_subcall
2012                 if (tcp->s_ent->sys_func == sys_socketcall) {
2013                         decode_socket_subcall(tcp);
2014                         break;
2015                 }
2016 # endif
2017 # ifdef SYS_ipc_subcall
2018                 if (tcp->s_ent->sys_func == sys_ipc) {
2019                         decode_ipc_subcall(tcp);
2020                         break;
2021                 }
2022 # endif
2023                 break;
2024         }
2025 #endif
2026
2027         if (need_fork_exec_workarounds)
2028                 syscall_fixup_for_fork_exec(tcp);
2029
2030         if (!(tcp->qual_flg & QUAL_TRACE)
2031          || (tracing_paths && !pathtrace_match(tcp))
2032         ) {
2033                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
2034                 return 0;
2035         }
2036
2037         tcp->flags &= ~TCB_FILTERED;
2038
2039         if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
2040                 res = 0;
2041                 goto ret;
2042         }
2043
2044 #ifdef USE_LIBUNWIND
2045         if (stack_trace_enabled) {
2046                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
2047                         unwind_capture_stacktrace(tcp);
2048         }
2049 #endif
2050
2051         printleader(tcp);
2052         if (tcp->qual_flg & UNDEFINED_SCNO)
2053                 tprintf("%s(", undefined_scno_name(tcp));
2054         else
2055                 tprintf("%s(", tcp->s_ent->sys_name);
2056         if ((tcp->qual_flg & QUAL_RAW) && tcp->s_ent->sys_func != sys_exit)
2057                 res = printargs(tcp);
2058         else
2059                 res = tcp->s_ent->sys_func(tcp);
2060
2061         fflush(tcp->outf);
2062  ret:
2063         tcp->flags |= TCB_INSYSCALL;
2064         /* Measure the entrance time as late as possible to avoid errors. */
2065         if (Tflag || cflag)
2066                 gettimeofday(&tcp->etime, NULL);
2067         return res;
2068 }
2069
2070 /* Returns:
2071  * 1: ok, continue in trace_syscall_exiting().
2072  * -1: error, trace_syscall_exiting() should print error indicator
2073  *    ("????" etc) and bail out.
2074  */
2075 static int
2076 get_syscall_result(struct tcb *tcp)
2077 {
2078 #if defined(S390) || defined(S390X)
2079         if (upeek(tcp->pid, PT_GPR2, &s390_gpr2) < 0)
2080                 return -1;
2081 #elif defined(POWERPC)
2082         /* already done by get_regs */
2083 #elif defined(AVR32)
2084         /* already done by get_regs */
2085 #elif defined(BFIN)
2086         if (upeek(tcp->pid, PT_R0, &bfin_r0) < 0)
2087                 return -1;
2088 #elif defined(I386)
2089         /* already done by get_regs */
2090 #elif defined(X86_64) || defined(X32)
2091         /* already done by get_regs */
2092 #elif defined(IA64)
2093 #       define IA64_PSR_IS      ((long)1 << 34)
2094         long psr;
2095         if (upeek(tcp->pid, PT_CR_IPSR, &psr) >= 0)
2096                 ia64_ia32mode = ((psr & IA64_PSR_IS) != 0);
2097         if (upeek(tcp->pid, PT_R8, &ia64_r8) < 0)
2098                 return -1;
2099         if (upeek(tcp->pid, PT_R10, &ia64_r10) < 0)
2100                 return -1;
2101 #elif defined(ARM)
2102         /* already done by get_regs */
2103 #elif defined(AARCH64)
2104         /* register reading already done by get_regs */
2105
2106         /* Used to do this, but we did it on syscall entry already: */
2107         /* We are in 64-bit mode (personality 1) if register struct is aarch64_regs,
2108          * else it's personality 0.
2109          */
2110         /*update_personality(tcp, aarch64_io.iov_len == sizeof(aarch64_regs));*/
2111 #elif defined(M68K)
2112         if (upeek(tcp->pid, 4*PT_D0, &m68k_d0) < 0)
2113                 return -1;
2114 #elif defined(LINUX_MIPSN32)
2115         unsigned long long regs[38];
2116
2117         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
2118                 return -1;
2119         mips_a3 = regs[REG_A3];
2120         mips_r2 = regs[REG_V0];
2121 #elif defined(MIPS)
2122         if (upeek(tcp->pid, REG_A3, &mips_a3) < 0)
2123                 return -1;
2124         if (upeek(tcp->pid, REG_V0, &mips_r2) < 0)
2125                 return -1;
2126 #elif defined(ALPHA)
2127         if (upeek(tcp->pid, REG_A3, &alpha_a3) < 0)
2128                 return -1;
2129         if (upeek(tcp->pid, REG_R0, &alpha_r0) < 0)
2130                 return -1;
2131 #elif defined(SPARC) || defined(SPARC64)
2132         /* already done by get_regs */
2133 #elif defined(HPPA)
2134         if (upeek(tcp->pid, PT_GR28, &hppa_r28) < 0)
2135                 return -1;
2136 #elif defined(SH)
2137         /* new syscall ABI returns result in R0 */
2138         if (upeek(tcp->pid, 4*REG_REG0, (long *)&sh_r0) < 0)
2139                 return -1;
2140 #elif defined(SH64)
2141         /* ABI defines result returned in r9 */
2142         if (upeek(tcp->pid, REG_GENERAL(9), (long *)&sh64_r9) < 0)
2143                 return -1;
2144 #elif defined(CRISV10) || defined(CRISV32)
2145         if (upeek(tcp->pid, 4*PT_R10, &cris_r10) < 0)
2146                 return -1;
2147 #elif defined(TILE)
2148         /* already done by get_regs */
2149 #elif defined(MICROBLAZE)
2150         if (upeek(tcp->pid, 3 * 4, &microblaze_r3) < 0)
2151                 return -1;
2152 #elif defined(OR1K)
2153         /* already done by get_regs */
2154 #elif defined(METAG)
2155         /* already done by get_regs */
2156 #elif defined(XTENSA)
2157         if (upeek(tcp->pid, REG_A_BASE + 2, &xtensa_a2) < 0)
2158                 return -1;
2159 #elif defined(ARC)
2160         /* already done by get_regs */
2161 #endif
2162         return 1;
2163 }
2164
2165 /* Called at each syscall exit */
2166 static void
2167 syscall_fixup_on_sysexit(struct tcb *tcp)
2168 {
2169 #if defined(S390) || defined(S390X)
2170         if ((tcp->flags & TCB_WAITEXECVE)
2171                  && (s390_gpr2 == -ENOSYS || s390_gpr2 == tcp->scno)) {
2172                 /*
2173                  * Return from execve.
2174                  * Fake a return value of zero.  We leave the TCB_WAITEXECVE
2175                  * flag set for the post-execve SIGTRAP to see and reset.
2176                  */
2177                 s390_gpr2 = 0;
2178         }
2179 #endif
2180 }
2181
2182 /*
2183  * Check the syscall return value register value for whether it is
2184  * a negated errno code indicating an error, or a success return value.
2185  */
2186 static inline int
2187 is_negated_errno(unsigned long int val)
2188 {
2189         unsigned long int max = -(long int) nerrnos;
2190 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
2191         if (current_wordsize < sizeof(val)) {
2192                 val = (unsigned int) val;
2193                 max = (unsigned int) max;
2194         }
2195 #endif
2196         return val > max;
2197 }
2198
2199 #if defined(X32)
2200 static inline int
2201 is_negated_errno_x32(unsigned long long val)
2202 {
2203         unsigned long long max = -(long long) nerrnos;
2204         /*
2205          * current_wordsize is 4 even in personality 0 (native X32)
2206          * but truncation _must not_ be done in it.
2207          * can't check current_wordsize here!
2208          */
2209         if (current_personality != 0) {
2210                 val = (uint32_t) val;
2211                 max = (uint32_t) max;
2212         }
2213         return val > max;
2214 }
2215 #endif
2216
2217 /* Returns:
2218  * 1: ok, continue in trace_syscall_exiting().
2219  * -1: error, trace_syscall_exiting() should print error indicator
2220  *    ("????" etc) and bail out.
2221  */
2222 static void
2223 get_error(struct tcb *tcp)
2224 {
2225         int u_error = 0;
2226         int check_errno = 1;
2227         if (tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS) {
2228                 check_errno = 0;
2229         }
2230 #if defined(S390) || defined(S390X)
2231         if (check_errno && is_negated_errno(s390_gpr2)) {
2232                 tcp->u_rval = -1;
2233                 u_error = -s390_gpr2;
2234         }
2235         else {
2236                 tcp->u_rval = s390_gpr2;
2237         }
2238 #elif defined(I386)
2239         if (check_errno && is_negated_errno(i386_regs.eax)) {
2240                 tcp->u_rval = -1;
2241                 u_error = -i386_regs.eax;
2242         }
2243         else {
2244                 tcp->u_rval = i386_regs.eax;
2245         }
2246 #elif defined(X86_64)
2247         long rax;
2248         if (x86_io.iov_len == sizeof(i386_regs)) {
2249                 /* Sign extend from 32 bits */
2250                 rax = (int32_t)i386_regs.eax;
2251         } else {
2252                 rax = x86_64_regs.rax;
2253         }
2254         if (check_errno && is_negated_errno(rax)) {
2255                 tcp->u_rval = -1;
2256                 u_error = -rax;
2257         }
2258         else {
2259                 tcp->u_rval = rax;
2260         }
2261 #elif defined(X32)
2262         /* In X32, return value is 64-bit (llseek uses one).
2263          * Using merely "long rax" would not work.
2264          */
2265         long long rax;
2266         if (x86_io.iov_len == sizeof(i386_regs)) {
2267                 /* Sign extend from 32 bits */
2268                 rax = (int32_t)i386_regs.eax;
2269         } else {
2270                 rax = x86_64_regs.rax;
2271         }
2272         /* Careful: is_negated_errno() works only on longs */
2273         if (check_errno && is_negated_errno_x32(rax)) {
2274                 tcp->u_rval = -1;
2275                 u_error = -rax;
2276         }
2277         else {
2278                 tcp->u_rval = rax; /* truncating */
2279                 tcp->u_lrval = rax;
2280         }
2281 #elif defined(IA64)
2282         if (ia64_ia32mode) {
2283                 int err;
2284
2285                 err = (int)ia64_r8;
2286                 if (check_errno && is_negated_errno(err)) {
2287                         tcp->u_rval = -1;
2288                         u_error = -err;
2289                 }
2290                 else {
2291                         tcp->u_rval = err;
2292                 }
2293         } else {
2294                 if (check_errno && ia64_r10) {
2295                         tcp->u_rval = -1;
2296                         u_error = ia64_r8;
2297                 } else {
2298                         tcp->u_rval = ia64_r8;
2299                 }
2300         }
2301 #elif defined(MIPS)
2302         if (check_errno && mips_a3) {
2303                 tcp->u_rval = -1;
2304                 u_error = mips_r2;
2305         } else {
2306                 tcp->u_rval = mips_r2;
2307 # if defined(LINUX_MIPSN32)
2308                 tcp->u_lrval = mips_r2;
2309 # endif
2310         }
2311 #elif defined(POWERPC)
2312         if (check_errno && (ppc_regs.ccr & 0x10000000)) {
2313                 tcp->u_rval = -1;
2314                 u_error = ppc_regs.gpr[3];
2315         }
2316         else {
2317                 tcp->u_rval = ppc_regs.gpr[3];
2318         }
2319 #elif defined(M68K)
2320         if (check_errno && is_negated_errno(m68k_d0)) {
2321                 tcp->u_rval = -1;
2322                 u_error = -m68k_d0;
2323         }
2324         else {
2325                 tcp->u_rval = m68k_d0;
2326         }
2327 #elif defined(ARM) || defined(AARCH64)
2328 # if defined(AARCH64)
2329         if (tcp->currpers == 1) {
2330                 if (check_errno && is_negated_errno(aarch64_regs.regs[0])) {
2331                         tcp->u_rval = -1;
2332                         u_error = -aarch64_regs.regs[0];
2333                 }
2334                 else {
2335                         tcp->u_rval = aarch64_regs.regs[0];
2336                 }
2337         }
2338         else
2339 # endif
2340         {
2341                 if (check_errno && is_negated_errno(arm_regs.ARM_r0)) {
2342                         tcp->u_rval = -1;
2343                         u_error = -arm_regs.ARM_r0;
2344                 }
2345                 else {
2346                         tcp->u_rval = arm_regs.ARM_r0;
2347                 }
2348         }
2349 #elif defined(AVR32)
2350         if (check_errno && avr32_regs.r12 && (unsigned) -avr32_regs.r12 < nerrnos) {
2351                 tcp->u_rval = -1;
2352                 u_error = -avr32_regs.r12;
2353         }
2354         else {
2355                 tcp->u_rval = avr32_regs.r12;
2356         }
2357 #elif defined(BFIN)
2358         if (check_errno && is_negated_errno(bfin_r0)) {
2359                 tcp->u_rval = -1;
2360                 u_error = -bfin_r0;
2361         } else {
2362                 tcp->u_rval = bfin_r0;
2363         }
2364 #elif defined(ALPHA)
2365         if (check_errno && alpha_a3) {
2366                 tcp->u_rval = -1;
2367                 u_error = alpha_r0;
2368         }
2369         else {
2370                 tcp->u_rval = alpha_r0;
2371         }
2372 #elif defined(SPARC)
2373         if (check_errno && sparc_regs.psr & PSR_C) {
2374                 tcp->u_rval = -1;
2375                 u_error = sparc_regs.u_regs[U_REG_O0];
2376         }
2377         else {
2378                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2379         }
2380 #elif defined(SPARC64)
2381         if (check_errno && sparc_regs.tstate & 0x1100000000UL) {
2382                 tcp->u_rval = -1;
2383                 u_error = sparc_regs.u_regs[U_REG_O0];
2384         }
2385         else {
2386                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2387         }
2388 #elif defined(HPPA)
2389         if (check_errno && is_negated_errno(hppa_r28)) {
2390                 tcp->u_rval = -1;
2391                 u_error = -hppa_r28;
2392         }
2393         else {
2394                 tcp->u_rval = hppa_r28;
2395         }
2396 #elif defined(SH)
2397         if (check_errno && is_negated_errno(sh_r0)) {
2398                 tcp->u_rval = -1;
2399                 u_error = -sh_r0;
2400         }
2401         else {
2402                 tcp->u_rval = sh_r0;
2403         }
2404 #elif defined(SH64)
2405         if (check_errno && is_negated_errno(sh64_r9)) {
2406                 tcp->u_rval = -1;
2407                 u_error = -sh64_r9;
2408         }
2409         else {
2410                 tcp->u_rval = sh64_r9;
2411         }
2412 #elif defined(METAG)
2413         /* result pointer in D0Re0 (D0.0) */
2414         if (check_errno && is_negated_errno(metag_regs.dx[0][0])) {
2415                 tcp->u_rval = -1;
2416                 u_error = -metag_regs.dx[0][0];
2417         }
2418         else {
2419                 tcp->u_rval = metag_regs.dx[0][0];
2420         }
2421 #elif defined(CRISV10) || defined(CRISV32)
2422         if (check_errno && cris_r10 && (unsigned) -cris_r10 < nerrnos) {
2423                 tcp->u_rval = -1;
2424                 u_error = -cris_r10;
2425         }
2426         else {
2427                 tcp->u_rval = cris_r10;
2428         }
2429 #elif defined(TILE)
2430         /*
2431          * The standard tile calling convention returns the value (or negative
2432          * errno) in r0, and zero (or positive errno) in r1.
2433          * Until at least kernel 3.8, however, the r1 value is not reflected
2434          * in ptregs at this point, so we use r0 here.
2435          */
2436         if (check_errno && is_negated_errno(tile_regs.regs[0])) {
2437                 tcp->u_rval = -1;
2438                 u_error = -tile_regs.regs[0];
2439         } else {
2440                 tcp->u_rval = tile_regs.regs[0];
2441         }
2442 #elif defined(MICROBLAZE)
2443         if (check_errno && is_negated_errno(microblaze_r3)) {
2444                 tcp->u_rval = -1;
2445                 u_error = -microblaze_r3;
2446         }
2447         else {
2448                 tcp->u_rval = microblaze_r3;
2449         }
2450 #elif defined(OR1K)
2451         if (check_errno && is_negated_errno(or1k_regs.gpr[11])) {
2452                 tcp->u_rval = -1;
2453                 u_error = -or1k_regs.gpr[11];
2454         }
2455         else {
2456                 tcp->u_rval = or1k_regs.gpr[11];
2457         }
2458 #elif defined(XTENSA)
2459         if (check_errno && is_negated_errno(xtensa_a2)) {
2460                 tcp->u_rval = -1;
2461                 u_error = -xtensa_a2;
2462         }
2463         else {
2464                 tcp->u_rval = xtensa_a2;
2465         }
2466 #elif defined(ARC)
2467         if (check_errno && is_negated_errno(arc_regs.scratch.r0)) {
2468                 tcp->u_rval = -1;
2469                 u_error = -arc_regs.scratch.r0;
2470         }
2471         else {
2472                 tcp->u_rval = arc_regs.scratch.r0;
2473         }
2474 #endif
2475         tcp->u_error = u_error;
2476 }
2477
2478 static void
2479 dumpio(struct tcb *tcp)
2480 {
2481         int (*func)();
2482
2483         if (syserror(tcp))
2484                 return;
2485         if ((unsigned long) tcp->u_arg[0] >= num_quals)
2486                 return;
2487         func = tcp->s_ent->sys_func;
2488         if (func == printargs)
2489                 return;
2490         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
2491                 if (func == sys_read ||
2492                     func == sys_pread ||
2493                     func == sys_recv ||
2494                     func == sys_recvfrom)
2495                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
2496                 else if (func == sys_readv)
2497                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2498                 return;
2499         }
2500         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
2501                 if (func == sys_write ||
2502                     func == sys_pwrite ||
2503                     func == sys_send ||
2504                     func == sys_sendto)
2505                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
2506                 else if (func == sys_writev)
2507                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2508                 return;
2509         }
2510 }
2511
2512 static int
2513 trace_syscall_exiting(struct tcb *tcp)
2514 {
2515         int sys_res;
2516         struct timeval tv;
2517         int res;
2518         long u_error;
2519
2520         /* Measure the exit time as early as possible to avoid errors. */
2521         if (Tflag || cflag)
2522                 gettimeofday(&tv, NULL);
2523
2524 #ifdef USE_LIBUNWIND
2525         if (stack_trace_enabled) {
2526                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
2527                         unwind_cache_invalidate(tcp);
2528         }
2529 #endif
2530
2531 #if SUPPORTED_PERSONALITIES > 1
2532         update_personality(tcp, tcp->currpers);
2533 #endif
2534         res = (get_regs_error ? -1 : get_syscall_result(tcp));
2535         if (res == 1) {
2536                 syscall_fixup_on_sysexit(tcp); /* never fails */
2537                 get_error(tcp); /* never fails */
2538                 if (need_fork_exec_workarounds)
2539                         syscall_fixup_for_fork_exec(tcp);
2540                 if (filtered(tcp) || hide_log_until_execve)
2541                         goto ret;
2542         }
2543
2544         if (cflag) {
2545                 count_syscall(tcp, &tv);
2546                 if (cflag == CFLAG_ONLY_STATS) {
2547                         goto ret;
2548                 }
2549         }
2550
2551         /* If not in -ff mode, and printing_tcp != tcp,
2552          * then the log currently does not end with output
2553          * of _our syscall entry_, but with something else.
2554          * We need to say which syscall's return is this.
2555          *
2556          * Forced reprinting via TCB_REPRINT is used only by
2557          * "strace -ff -oLOG test/threaded_execve" corner case.
2558          * It's the only case when -ff mode needs reprinting.
2559          */
2560         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
2561                 tcp->flags &= ~TCB_REPRINT;
2562                 printleader(tcp);
2563                 if (tcp->qual_flg & UNDEFINED_SCNO)
2564                         tprintf("<... %s resumed> ", undefined_scno_name(tcp));
2565                 else
2566                         tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
2567         }
2568         printing_tcp = tcp;
2569
2570         if (res != 1) {
2571                 /* There was error in one of prior ptrace ops */
2572                 tprints(") ");
2573                 tabto();
2574                 tprints("= ? <unavailable>\n");
2575                 line_ended();
2576                 tcp->flags &= ~TCB_INSYSCALL;
2577                 return res;
2578         }
2579
2580         sys_res = 0;
2581         if (tcp->qual_flg & QUAL_RAW) {
2582                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
2583         } else {
2584         /* FIXME: not_failing_only (IOW, option -z) is broken:
2585          * failure of syscall is known only after syscall return.
2586          * Thus we end up with something like this on, say, ENOENT:
2587          *     open("doesnt_exist", O_RDONLY <unfinished ...>
2588          *     {next syscall decode}
2589          * whereas the intended result is that open(...) line
2590          * is not shown at all.
2591          */
2592                 if (not_failing_only && tcp->u_error)
2593                         goto ret;       /* ignore failed syscalls */
2594                 sys_res = tcp->s_ent->sys_func(tcp);
2595         }
2596
2597         tprints(") ");
2598         tabto();
2599         u_error = tcp->u_error;
2600         if (tcp->qual_flg & QUAL_RAW) {
2601                 if (u_error)
2602                         tprintf("= -1 (errno %ld)", u_error);
2603                 else
2604                         tprintf("= %#lx", tcp->u_rval);
2605         }
2606         else if (!(sys_res & RVAL_NONE) && u_error) {
2607                 switch (u_error) {
2608                 /* Blocked signals do not interrupt any syscalls.
2609                  * In this case syscalls don't return ERESTARTfoo codes.
2610                  *
2611                  * Deadly signals set to SIG_DFL interrupt syscalls
2612                  * and kill the process regardless of which of the codes below
2613                  * is returned by the interrupted syscall.
2614                  * In some cases, kernel forces a kernel-generated deadly
2615                  * signal to be unblocked and set to SIG_DFL (and thus cause
2616                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
2617                  * or SIGILL. (The alternative is to leave process spinning
2618                  * forever on the faulty instruction - not useful).
2619                  *
2620                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
2621                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
2622                  * but kernel will always restart them.
2623                  */
2624                 case ERESTARTSYS:
2625                         /* Most common type of signal-interrupted syscall exit code.
2626                          * The system call will be restarted with the same arguments
2627                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
2628                          */
2629                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
2630                         break;
2631                 case ERESTARTNOINTR:
2632                         /* Rare. For example, fork() returns this if interrupted.
2633                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
2634                          */
2635                         tprints("= ? ERESTARTNOINTR (To be restarted)");
2636                         break;
2637                 case ERESTARTNOHAND:
2638                         /* pause(), rt_sigsuspend() etc use this code.
2639                          * SA_RESTART is ignored (assumed not set):
2640                          * syscall won't restart (will return EINTR instead)
2641                          * even after signal with SA_RESTART set. However,
2642                          * after SIG_IGN or SIG_DFL signal it will restart
2643                          * (thus the name "restart only if has no handler").
2644                          */
2645                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
2646                         break;
2647                 case ERESTART_RESTARTBLOCK:
2648                         /* Syscalls like nanosleep(), poll() which can't be
2649                          * restarted with their original arguments use this
2650                          * code. Kernel will execute restart_syscall() instead,
2651                          * which changes arguments before restarting syscall.
2652                          * SA_RESTART is ignored (assumed not set) similarly
2653                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
2654                          * since restart data is saved in "restart block"
2655                          * in task struct, and if signal handler uses a syscall
2656                          * which in turn saves another such restart block,
2657                          * old data is lost and restart becomes impossible)
2658                          */
2659                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
2660                         break;
2661                 default:
2662                         if (u_error < 0)
2663                                 tprintf("= -1 E??? (errno %ld)", u_error);
2664                         else if ((unsigned long) u_error < nerrnos)
2665                                 tprintf("= -1 %s (%s)", errnoent[u_error],
2666                                         strerror(u_error));
2667                         else
2668                                 tprintf("= -1 ERRNO_%ld (%s)", u_error,
2669                                         strerror(u_error));
2670                         break;
2671                 }
2672                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2673                         tprintf(" (%s)", tcp->auxstr);
2674         }
2675         else {
2676                 if (sys_res & RVAL_NONE)
2677                         tprints("= ?");
2678                 else {
2679                         switch (sys_res & RVAL_MASK) {
2680                         case RVAL_HEX:
2681                                 tprintf("= %#lx", tcp->u_rval);
2682                                 break;
2683                         case RVAL_OCTAL:
2684                                 tprintf("= %#lo", tcp->u_rval);
2685                                 break;
2686                         case RVAL_UDECIMAL:
2687                                 tprintf("= %lu", tcp->u_rval);
2688                                 break;
2689                         case RVAL_DECIMAL:
2690                                 tprintf("= %ld", tcp->u_rval);
2691                                 break;
2692                         case RVAL_FD:
2693                                 if (show_fd_path) {
2694                                         tprints("= ");
2695                                         printfd(tcp, tcp->u_rval);
2696                                 }
2697                                 else
2698                                         tprintf("= %ld", tcp->u_rval);
2699                                 break;
2700 #if defined(LINUX_MIPSN32) || defined(X32)
2701                         /*
2702                         case RVAL_LHEX:
2703                                 tprintf("= %#llx", tcp->u_lrval);
2704                                 break;
2705                         case RVAL_LOCTAL:
2706                                 tprintf("= %#llo", tcp->u_lrval);
2707                                 break;
2708                         */
2709                         case RVAL_LUDECIMAL:
2710                                 tprintf("= %llu", tcp->u_lrval);
2711                                 break;
2712                         /*
2713                         case RVAL_LDECIMAL:
2714                                 tprintf("= %lld", tcp->u_lrval);
2715                                 break;
2716                         */
2717 #endif
2718                         default:
2719                                 fprintf(stderr,
2720                                         "invalid rval format\n");
2721                                 break;
2722                         }
2723                 }
2724                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2725                         tprintf(" (%s)", tcp->auxstr);
2726         }
2727         if (Tflag) {
2728                 tv_sub(&tv, &tv, &tcp->etime);
2729                 tprintf(" <%ld.%06ld>",
2730                         (long) tv.tv_sec, (long) tv.tv_usec);
2731         }
2732         tprints("\n");
2733         dumpio(tcp);
2734         line_ended();
2735
2736 #ifdef USE_LIBUNWIND
2737         if (stack_trace_enabled)
2738                 unwind_print_stacktrace(tcp);
2739 #endif
2740
2741  ret:
2742         tcp->flags &= ~TCB_INSYSCALL;
2743         return 0;
2744 }
2745
2746 int
2747 trace_syscall(struct tcb *tcp)
2748 {
2749         return exiting(tcp) ?
2750                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
2751 }