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 # ifndef PTRACE_PEEKUSR
  41 #  define PTRACE_PEEKUSR PTRACE_PEEKUSER
  42 # endif
  43 #elif defined(HAVE_LINUX_PTRACE_H)
  44 # undef PTRACE_SYSCALL
  45 # ifdef HAVE_STRUCT_IA64_FPREG
  46 #  define ia64_fpreg XXX_ia64_fpreg
  47 # endif
  48 # ifdef HAVE_STRUCT_PT_ALL_USER_REGS
  49 #  define pt_all_user_regs XXX_pt_all_user_regs
  50 # endif
  51 # include <linux/ptrace.h>
  52 # undef ia64_fpreg
  53 # undef pt_all_user_regs
  54 #endif
  55
  56 #if defined(SPARC64)
  57 # undef PTRACE_GETREGS
  58 # define PTRACE_GETREGS PTRACE_GETREGS64
  59 # undef PTRACE_SETREGS
  60 # define PTRACE_SETREGS PTRACE_SETREGS64
  61 #endif
  62
  63 #if defined(IA64)
  64 # include <asm/ptrace_offsets.h>
  65 # include <asm/rse.h>
  66 #endif
  67
  68 #if defined(X86_64) || defined(X32)
  69 # include <linux/ptrace.h>
  70 # include <sys/uio.h>
  71 # include <elf.h>
  72 #endif
  73
  74 #if defined(AARCH64)
  75 # include <asm/ptrace.h>
  76 # include <sys/uio.h>
  77 # include <elf.h>
  78 #endif
  79
  80 #if defined(OR1K)
  81 # include <sys/uio.h>
  82 # include <elf.h>
  83 #endif
  84
  85 #ifndef ERESTARTSYS
  86 # define ERESTARTSYS    512
  87 #endif
  88 #ifndef ERESTARTNOINTR
  89 # define ERESTARTNOINTR 513
  90 #endif
  91 #ifndef ERESTARTNOHAND
  92 # define ERESTARTNOHAND 514     /* restart if no handler */
  93 #endif
  94 #ifndef ERESTART_RESTARTBLOCK
  95 # define ERESTART_RESTARTBLOCK 516      /* restart by calling sys_restart_syscall */
  96 #endif
  97
  98 #ifndef NSIG
  99 # warning: NSIG is not defined, using 32
 100 # define NSIG 32
 101 #endif
 102 #ifdef ARM
 103 /* Ugh. Is this really correct? ARM has no RT signals?! */
 104 # undef NSIG
 105 # define NSIG 32
 106 #endif
 107
 108 #include "syscall.h"
 109
 110 /* Define these shorthand notations to simplify the syscallent files. */
 111 #define TD TRACE_DESC
 112 #define TF TRACE_FILE
 113 #define TI TRACE_IPC
 114 #define TN TRACE_NETWORK
 115 #define TP TRACE_PROCESS
 116 #define TS TRACE_SIGNAL
 117 #define TM TRACE_MEMORY
 118 #define NF SYSCALL_NEVER_FAILS
 119 #define MA MAX_ARGS
 120
 121 const struct_sysent sysent0[] = {
 122 #include "syscallent.h"
 123 };
 124
 125 #if SUPPORTED_PERSONALITIES > 1
 126 static const struct_sysent sysent1[] = {
 127 # include "syscallent1.h"
 128 };
 129 #endif
 130
 131 #if SUPPORTED_PERSONALITIES > 2
 132 static const struct_sysent sysent2[] = {
 133 # include "syscallent2.h"
 134 };
 135 #endif
 136
 137 /* Now undef them since short defines cause wicked namespace pollution. */
 138 #undef TD
 139 #undef TF
 140 #undef TI
 141 #undef TN
 142 #undef TP
 143 #undef TS
 144 #undef TM
 145 #undef NF
 146 #undef MA
 147
 148 /*
 149  * `ioctlent.h' may be generated from `ioctlent.raw' by the auxiliary
 150  * program `ioctlsort', such that the list is sorted by the `code' field.
 151  * This has the side-effect of resolving the _IO.. macros into
 152  * plain integers, eliminating the need to include here everything
 153  * in "/usr/include".
 154  */
 155
 156 const char *const errnoent0[] = {
 157 #include "errnoent.h"
 158 };
 159 const char *const signalent0[] = {
 160 #include "signalent.h"
 161 };
 162 const struct_ioctlent ioctlent0[] = {
 163 #include "ioctlent.h"
 164 };
 165 enum { nsyscalls0 = ARRAY_SIZE(sysent0) };
 166 enum { nerrnos0 = ARRAY_SIZE(errnoent0) };
 167 enum { nsignals0 = ARRAY_SIZE(signalent0) };
 168 enum { nioctlents0 = ARRAY_SIZE(ioctlent0) };
 169
 170 #if SUPPORTED_PERSONALITIES > 1
 171 static const char *const errnoent1[] = {
 172 # include "errnoent1.h"
 173 };
 174 static const char *const signalent1[] = {
 175 # include "signalent1.h"
 176 };
 177 static const struct_ioctlent ioctlent1[] = {
 178 # include "ioctlent1.h"
 179 };
 180 enum { nsyscalls1 = ARRAY_SIZE(sysent1) };
 181 enum { nerrnos1 = ARRAY_SIZE(errnoent1) };
 182 enum { nsignals1 = ARRAY_SIZE(signalent1) };
 183 enum { nioctlents1 = ARRAY_SIZE(ioctlent1) };
 184 #endif
 185
 186 #if SUPPORTED_PERSONALITIES > 2
 187 static const char *const errnoent2[] = {
 188 # include "errnoent2.h"
 189 };
 190 static const char *const signalent2[] = {
 191 # include "signalent2.h"
 192 };
 193 static const struct_ioctlent ioctlent2[] = {
 194 # include "ioctlent2.h"
 195 };
 196 enum { nsyscalls2 = ARRAY_SIZE(sysent2) };
 197 enum { nerrnos2 = ARRAY_SIZE(errnoent2) };
 198 enum { nsignals2 = ARRAY_SIZE(signalent2) };
 199 enum { nioctlents2 = ARRAY_SIZE(ioctlent2) };
 200 #endif
 201
 202 #if SUPPORTED_PERSONALITIES > 1
 203 const struct_sysent *sysent = sysent0;
 204 const char *const *errnoent = errnoent0;
 205 const char *const *signalent = signalent0;
 206 const struct_ioctlent *ioctlent = ioctlent0;
 207 #endif
 208 unsigned nsyscalls = nsyscalls0;
 209 unsigned nerrnos = nerrnos0;
 210 unsigned nsignals = nsignals0;
 211 unsigned nioctlents = nioctlents0;
 212
 213 unsigned num_quals;
 214 qualbits_t *qual_vec[SUPPORTED_PERSONALITIES];
 215
 216 static const unsigned nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 217         nsyscalls0,
 218 #if SUPPORTED_PERSONALITIES > 1
 219         nsyscalls1,
 220 #endif
 221 #if SUPPORTED_PERSONALITIES > 2
 222         nsyscalls2,
 223 #endif
 224 };
 225 static const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 226         sysent0,
 227 #if SUPPORTED_PERSONALITIES > 1
 228         sysent1,
 229 #endif
 230 #if SUPPORTED_PERSONALITIES > 2
 231         sysent2,
 232 #endif
 233 };
 234
 235 enum {
 236         MAX_NSYSCALLS1 = (nsyscalls0
 237 #if SUPPORTED_PERSONALITIES > 1
 238                         > nsyscalls1 ? nsyscalls0 : nsyscalls1
 239 #endif
 240                         ),
 241         MAX_NSYSCALLS2 = (MAX_NSYSCALLS1
 242 #if SUPPORTED_PERSONALITIES > 2
 243                         > nsyscalls2 ? MAX_NSYSCALLS1 : nsyscalls2
 244 #endif
 245                         ),
 246         MAX_NSYSCALLS = MAX_NSYSCALLS2,
 247         /* We are ready for arches with up to 255 signals,
 248          * even though the largest known signo is on MIPS and it is 128.
 249          * The number of existing syscalls on all arches is
 250          * larger that 255 anyway, so it is just a pedantic matter.
 251          */
 252         MIN_QUALS = MAX_NSYSCALLS > 255 ? MAX_NSYSCALLS : 255
 253 };
 254
 255 #if SUPPORTED_PERSONALITIES > 1
 256 unsigned current_personality;
 257
 258 # ifndef current_wordsize
 259 unsigned current_wordsize;
 260 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 261         PERSONALITY0_WORDSIZE,
 262         PERSONALITY1_WORDSIZE,
 263 # if SUPPORTED_PERSONALITIES > 2
 264         PERSONALITY2_WORDSIZE,
 265 # endif
 266 };
 267 # endif
 268
 269 void
 270 set_personality(int personality)
 271 {
 272         nsyscalls = nsyscall_vec[personality];
 273         sysent = sysent_vec[personality];
 274
 275         switch (personality) {
 276         case 0:
 277                 errnoent = errnoent0;
 278                 nerrnos = nerrnos0;
 279                 ioctlent = ioctlent0;
 280                 nioctlents = nioctlents0;
 281                 signalent = signalent0;
 282                 nsignals = nsignals0;
 283                 break;
 284
 285         case 1:
 286                 errnoent = errnoent1;
 287                 nerrnos = nerrnos1;
 288                 ioctlent = ioctlent1;
 289                 nioctlents = nioctlents1;
 290                 signalent = signalent1;
 291                 nsignals = nsignals1;
 292                 break;
 293
 294 # if SUPPORTED_PERSONALITIES > 2
 295         case 2:
 296                 errnoent = errnoent2;
 297                 nerrnos = nerrnos2;
 298                 ioctlent = ioctlent2;
 299                 nioctlents = nioctlents2;
 300                 signalent = signalent2;
 301                 nsignals = nsignals2;
 302                 break;
 303 # endif
 304         }
 305
 306         current_personality = personality;
 307 # ifndef current_wordsize
 308         current_wordsize = personality_wordsize[personality];
 309 # endif
 310 }
 311
 312 static void
 313 update_personality(struct tcb *tcp, int personality)
 314 {
 315         if (personality == current_personality)
 316                 return;
 317         set_personality(personality);
 318
 319         if (personality == tcp->currpers)
 320                 return;
 321         tcp->currpers = personality;
 322
 323 # if defined(POWERPC64)
 324         if (!qflag) {
 325                 static const char *const names[] = {"64 bit", "32 bit"};
 326                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 327                         tcp->pid, names[personality]);
 328         }
 329 # elif defined(X86_64)
 330         if (!qflag) {
 331                 static const char *const names[] = {"64 bit", "32 bit", "x32"};
 332                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 333                         tcp->pid, names[personality]);
 334         }
 335 # elif defined(X32)
 336         if (!qflag) {
 337                 static const char *const names[] = {"x32", "32 bit"};
 338                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 339                         tcp->pid, names[personality]);
 340         }
 341 # elif defined(AARCH64)
 342         if (!qflag) {
 343                 static const char *const names[] = {"32-bit", "AArch64"};
 344                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 345                         tcp->pid, names[personality]);
 346         }
 347 # elif defined(TILE)
 348         if (!qflag) {
 349                 static const char *const names[] = {"64-bit", "32-bit"};
 350                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 351                         tcp->pid, names[personality]);
 352         }
 353 # endif
 354 }
 355 #endif
 356
 357 static int qual_syscall(), qual_signal(), qual_desc();
 358
 359 static const struct qual_options {
 360         int bitflag;
 361         const char *option_name;
 362         int (*qualify)(const char *, int, int);
 363         const char *argument_name;
 364 } qual_options[] = {
 365         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
 366         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
 367         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
 368         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
 369         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
 370         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
 371         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
 372         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
 373         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
 374         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
 375         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
 376         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
 377         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
 378         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
 379         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
 380         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
 381         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
 382         { 0,            NULL,           NULL,           NULL            },
 383 };
 384
 385 static void
 386 reallocate_qual(int n)
 387 {
 388         unsigned p;
 389         qualbits_t *qp;
 390         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 391                 qp = qual_vec[p] = realloc(qual_vec[p], n * sizeof(qualbits_t));
 392                 if (!qp)
 393                         die_out_of_memory();
 394                 memset(&qp[num_quals], 0, (n - num_quals) * sizeof(qualbits_t));
 395         }
 396         num_quals = n;
 397 }
 398
 399 static void
 400 qualify_one(int n, int bitflag, int not, int pers)
 401 {
 402         unsigned p;
 403
 404         if (num_quals <= n)
 405                 reallocate_qual(n + 1);
 406
 407         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 408                 if (pers == p || pers < 0) {
 409                         if (not)
 410                                 qual_vec[p][n] &= ~bitflag;
 411                         else
 412                                 qual_vec[p][n] |= bitflag;
 413                 }
 414         }
 415 }
 416
 417 static int
 418 qual_syscall(const char *s, int bitflag, int not)
 419 {
 420         unsigned p;
 421         unsigned i;
 422         int rc = -1;
 423
 424         if (*s >= '0' && *s <= '9') {
 425                 i = string_to_uint(s);
 426                 if (i > MAX_NSYSCALLS)
 427                         return -1;
 428                 qualify_one(i, bitflag, not, -1);
 429                 return 0;
 430         }
 431
 432         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 433                 for (i = 0; i < nsyscall_vec[p]; i++) {
 434                         if (sysent_vec[p][i].sys_name
 435                          && strcmp(s, sysent_vec[p][i].sys_name) == 0
 436                         ) {
 437                                 qualify_one(i, bitflag, not, 0);
 438                                 rc = 0;
 439                         }
 440                 }
 441         }
 442
 443         return rc;
 444 }
 445
 446 static int
 447 qual_signal(const char *s, int bitflag, int not)
 448 {
 449         int i;
 450
 451         if (*s >= '0' && *s <= '9') {
 452                 int signo = string_to_uint(s);
 453                 if (signo < 0 || signo > 255)
 454                         return -1;
 455                 qualify_one(signo, bitflag, not, -1);
 456                 return 0;
 457         }
 458         if (strncasecmp(s, "SIG", 3) == 0)
 459                 s += 3;
 460         for (i = 0; i <= NSIG; i++) {
 461                 if (strcasecmp(s, signame(i) + 3) == 0) {
 462                         qualify_one(i, bitflag, not, -1);
 463                         return 0;
 464                 }
 465         }
 466         return -1;
 467 }
 468
 469 static int
 470 qual_desc(const char *s, int bitflag, int not)
 471 {
 472         if (*s >= '0' && *s <= '9') {
 473                 int desc = string_to_uint(s);
 474                 if (desc < 0 || desc > 0x7fff) /* paranoia */
 475                         return -1;
 476                 qualify_one(desc, bitflag, not, -1);
 477                 return 0;
 478         }
 479         return -1;
 480 }
 481
 482 static int
 483 lookup_class(const char *s)
 484 {
 485         if (strcmp(s, "file") == 0)
 486                 return TRACE_FILE;
 487         if (strcmp(s, "ipc") == 0)
 488                 return TRACE_IPC;
 489         if (strcmp(s, "network") == 0)
 490                 return TRACE_NETWORK;
 491         if (strcmp(s, "process") == 0)
 492                 return TRACE_PROCESS;
 493         if (strcmp(s, "signal") == 0)
 494                 return TRACE_SIGNAL;
 495         if (strcmp(s, "desc") == 0)
 496                 return TRACE_DESC;
 497         if (strcmp(s, "memory") == 0)
 498                 return TRACE_MEMORY;
 499         return -1;
 500 }
 501
 502 void
 503 qualify(const char *s)
 504 {
 505         const struct qual_options *opt;
 506         int not;
 507         char *copy;
 508         const char *p;
 509         int i, n;
 510
 511         if (num_quals == 0)
 512                 reallocate_qual(MIN_QUALS);
 513
 514         opt = &qual_options[0];
 515         for (i = 0; (p = qual_options[i].option_name); i++) {
 516                 n = strlen(p);
 517                 if (strncmp(s, p, n) == 0 && s[n] == '=') {
 518                         opt = &qual_options[i];
 519                         s += n + 1;
 520                         break;
 521                 }
 522         }
 523         not = 0;
 524         if (*s == '!') {
 525                 not = 1;
 526                 s++;
 527         }
 528         if (strcmp(s, "none") == 0) {
 529                 not = 1 - not;
 530                 s = "all";
 531         }
 532         if (strcmp(s, "all") == 0) {
 533                 for (i = 0; i < num_quals; i++) {
 534                         qualify_one(i, opt->bitflag, not, -1);
 535                 }
 536                 return;
 537         }
 538         for (i = 0; i < num_quals; i++) {
 539                 qualify_one(i, opt->bitflag, !not, -1);
 540         }
 541         copy = strdup(s);
 542         if (!copy)
 543                 die_out_of_memory();
 544         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
 545                 if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
 546                         unsigned pers;
 547                         for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
 548                                 for (i = 0; i < nsyscall_vec[pers]; i++)
 549                                         if (sysent_vec[pers][i].sys_flags & n)
 550                                                 qualify_one(i, opt->bitflag, not, 0);
 551                         }
 552                         continue;
 553                 }
 554                 if (opt->qualify(p, opt->bitflag, not)) {
 555                         error_msg_and_die("invalid %s '%s'",
 556                                 opt->argument_name, p);
 557                 }
 558         }
 559         free(copy);
 560         return;
 561 }
 562
 563 #ifdef SYS_socket_subcall
 564 static void
 565 decode_socket_subcall(struct tcb *tcp)
 566 {
 567         unsigned long addr;
 568         unsigned int i, n, size;
 569
 570         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_socket_nsubcalls)
 571                 return;
 572
 573         tcp->scno = SYS_socket_subcall + tcp->u_arg[0];
 574         tcp->qual_flg = qual_flags[tcp->scno];
 575         tcp->s_ent = &sysent[tcp->scno];
 576         addr = tcp->u_arg[1];
 577         size = current_wordsize;
 578         n = tcp->s_ent->nargs;
 579         for (i = 0; i < n; ++i) {
 580                 if (size == sizeof(int)) {
 581                         unsigned int arg;
 582                         if (umove(tcp, addr, &arg) < 0)
 583                                 arg = 0;
 584                         tcp->u_arg[i] = arg;
 585                 }
 586                 else {
 587                         unsigned long arg;
 588                         if (umove(tcp, addr, &arg) < 0)
 589                                 arg = 0;
 590                         tcp->u_arg[i] = arg;
 591                 }
 592                 addr += size;
 593         }
 594 }
 595 #endif
 596
 597 #ifdef SYS_ipc_subcall
 598 static void
 599 decode_ipc_subcall(struct tcb *tcp)
 600 {
 601         unsigned int i, n;
 602
 603         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_ipc_nsubcalls)
 604                 return;
 605
 606         tcp->scno = SYS_ipc_subcall + tcp->u_arg[0];
 607         tcp->qual_flg = qual_flags[tcp->scno];
 608         tcp->s_ent = &sysent[tcp->scno];
 609         n = tcp->s_ent->nargs;
 610         for (i = 0; i < n; i++)
 611                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 612 }
 613 #endif
 614
 615 int
 616 printargs(struct tcb *tcp)
 617 {
 618         if (entering(tcp)) {
 619                 int i;
 620                 int n = tcp->s_ent->nargs;
 621                 for (i = 0; i < n; i++)
 622                         tprintf("%s%#lx", i ? ", " : "", tcp->u_arg[i]);
 623         }
 624         return 0;
 625 }
 626
 627 int
 628 printargs_lu(struct tcb *tcp)
 629 {
 630         if (entering(tcp)) {
 631                 int i;
 632                 int n = tcp->s_ent->nargs;
 633                 for (i = 0; i < n; i++)
 634                         tprintf("%s%lu", i ? ", " : "", tcp->u_arg[i]);
 635         }
 636         return 0;
 637 }
 638
 639 int
 640 printargs_ld(struct tcb *tcp)
 641 {
 642         if (entering(tcp)) {
 643                 int i;
 644                 int n = tcp->s_ent->nargs;
 645                 for (i = 0; i < n; i++)
 646                         tprintf("%s%ld", i ? ", " : "", tcp->u_arg[i]);
 647         }
 648         return 0;
 649 }
 650
 651 #if defined(SPARC) || defined(SPARC64) || defined(IA64) || defined(SH)
 652 long
 653 getrval2(struct tcb *tcp)
 654 {
 655         long val;
 656
 657 # if defined(SPARC) || defined(SPARC64)
 658         val = sparc_regs.u_regs[U_REG_O1];
 659 # elif defined(SH)
 660         if (upeek(tcp, 4*(REG_REG0+1), &val) < 0)
 661                 return -1;
 662 # elif defined(IA64)
 663         if (upeek(tcp, PT_R9, &val) < 0)
 664                 return -1;
 665 # endif
 666
 667         return val;
 668 }
 669 #endif
 670
 671 int
 672 is_restart_error(struct tcb *tcp)
 673 {
 674         switch (tcp->u_error) {
 675                 case ERESTARTSYS:
 676                 case ERESTARTNOINTR:
 677                 case ERESTARTNOHAND:
 678                 case ERESTART_RESTARTBLOCK:
 679                         return 1;
 680                 default:
 681                         break;
 682         }
 683         return 0;
 684 }
 685
 686 #if defined(I386)
 687 struct user_regs_struct i386_regs;
 688 #elif defined(X86_64) || defined(X32)
 689 /*
 690  * On i386, pt_regs and user_regs_struct are the same,
 691  * but on 64 bit x86, user_regs_struct has six more fields:
 692  * fs_base, gs_base, ds, es, fs, gs.
 693  * PTRACE_GETREGS fills them too, so struct pt_regs would overflow.
 694  */
 695 struct i386_user_regs_struct {
 696         uint32_t ebx;
 697         uint32_t ecx;
 698         uint32_t edx;
 699         uint32_t esi;
 700         uint32_t edi;
 701         uint32_t ebp;
 702         uint32_t eax;
 703         uint32_t xds;
 704         uint32_t xes;
 705         uint32_t xfs;
 706         uint32_t xgs;
 707         uint32_t orig_eax;
 708         uint32_t eip;
 709         uint32_t xcs;
 710         uint32_t eflags;
 711         uint32_t esp;
 712         uint32_t xss;
 713 };
 714 static union {
 715         struct user_regs_struct      x86_64_r;
 716         struct i386_user_regs_struct i386_r;
 717 } x86_regs_union;
 718 # define x86_64_regs x86_regs_union.x86_64_r
 719 # define i386_regs   x86_regs_union.i386_r
 720 static struct iovec x86_io = {
 721         .iov_base = &x86_regs_union
 722 };
 723 #elif defined(IA64)
 724 long ia32 = 0; /* not static */
 725 static long ia64_r8, ia64_r10;
 726 #elif defined(POWERPC)
 727 static long ppc_result;
 728 #elif defined(M68K)
 729 static long m68k_d0;
 730 #elif defined(BFIN)
 731 static long bfin_r0;
 732 #elif defined(ARM)
 733 struct pt_regs arm_regs; /* not static */
 734 #elif defined(AARCH64)
 735 static union {
 736         struct user_pt_regs aarch64_r;
 737         struct arm_pt_regs  arm_r;
 738 } arm_regs_union;
 739 # define aarch64_regs arm_regs_union.aarch64_r
 740 # define arm_regs     arm_regs_union.arm_r
 741 static struct iovec aarch64_io = {
 742         .iov_base = &arm_regs_union
 743 };
 744 #elif defined(ALPHA)
 745 static long alpha_r0;
 746 static long alpha_a3;
 747 #elif defined(AVR32)
 748 static struct pt_regs avr32_regs;
 749 #elif defined(SPARC) || defined(SPARC64)
 750 struct pt_regs sparc_regs; /* not static */
 751 #elif defined(LINUX_MIPSN32)
 752 static long long mips_a3;
 753 static long long mips_r2;
 754 #elif defined(MIPS)
 755 static long mips_a3;
 756 static long mips_r2;
 757 #elif defined(S390) || defined(S390X)
 758 static long gpr2;
 759 static long syscall_mode;
 760 #elif defined(HPPA)
 761 static long hppa_r28;
 762 #elif defined(SH)
 763 static long sh_r0;
 764 #elif defined(SH64)
 765 static long sh64_r9;
 766 #elif defined(CRISV10) || defined(CRISV32)
 767 static long cris_r10;
 768 #elif defined(TILE)
 769 struct pt_regs tile_regs;
 770 #elif defined(MICROBLAZE)
 771 static long microblaze_r3;
 772 #elif defined(OR1K)
 773 static struct user_regs_struct or1k_regs;
 774 static struct iovec or1k_io = {
 775         .iov_base = &or1k_regs
 776 };
 777 #endif
 778
 779 void
 780 printcall(struct tcb *tcp)
 781 {
 782 #define PRINTBADPC tprintf(sizeof(long) == 4 ? "[????????] " : \
 783                            sizeof(long) == 8 ? "[????????????????] " : \
 784                            NULL /* crash */)
 785         if (get_regs_error) {
 786                 PRINTBADPC;
 787                 return;
 788         }
 789 #if defined(I386)
 790         tprintf("[%08lx] ", i386_regs.eip);
 791 #elif defined(S390) || defined(S390X)
 792         long psw;
 793         if (upeek(tcp, PT_PSWADDR, &psw) < 0) {
 794                 PRINTBADPC;
 795                 return;
 796         }
 797 # ifdef S390
 798         tprintf("[%08lx] ", psw);
 799 # elif S390X
 800         tprintf("[%016lx] ", psw);
 801 # endif
 802 #elif defined(X86_64) || defined(X32)
 803         if (x86_io.iov_len == sizeof(i386_regs)) {
 804                 tprintf("[%08x] ", (unsigned) i386_regs.eip);
 805         } else {
 806 # if defined(X86_64)
 807                 tprintf("[%016lx] ", (unsigned long) x86_64_regs.rip);
 808 # elif defined(X32)
 809                 /* Note: this truncates 64-bit rip to 32 bits */
 810                 tprintf("[%08lx] ", (unsigned long) x86_64_regs.rip);
 811 # endif
 812         }
 813 #elif defined(IA64)
 814         long ip;
 815         if (upeek(tcp, PT_B0, &ip) < 0) {
 816                 PRINTBADPC;
 817                 return;
 818         }
 819         tprintf("[%08lx] ", ip);
 820 #elif defined(POWERPC)
 821         long pc;
 822         if (upeek(tcp, sizeof(unsigned long)*PT_NIP, &pc) < 0) {
 823                 PRINTBADPC;
 824                 return;
 825         }
 826 # ifdef POWERPC64
 827         tprintf("[%016lx] ", pc);
 828 # else
 829         tprintf("[%08lx] ", pc);
 830 # endif
 831 #elif defined(M68K)
 832         long pc;
 833         if (upeek(tcp, 4*PT_PC, &pc) < 0) {
 834                 tprints("[????????] ");
 835                 return;
 836         }
 837         tprintf("[%08lx] ", pc);
 838 #elif defined(ALPHA)
 839         long pc;
 840         if (upeek(tcp, REG_PC, &pc) < 0) {
 841                 tprints("[????????????????] ");
 842                 return;
 843         }
 844         tprintf("[%08lx] ", pc);
 845 #elif defined(SPARC)
 846         tprintf("[%08lx] ", sparc_regs.pc);
 847 #elif defined(SPARC64)
 848         tprintf("[%08lx] ", sparc_regs.tpc);
 849 #elif defined(HPPA)
 850         long pc;
 851         if (upeek(tcp, PT_IAOQ0, &pc) < 0) {
 852                 tprints("[????????] ");
 853                 return;
 854         }
 855         tprintf("[%08lx] ", pc);
 856 #elif defined(MIPS)
 857         long pc;
 858         if (upeek(tcp, REG_EPC, &pc) < 0) {
 859                 tprints("[????????] ");
 860                 return;
 861         }
 862         tprintf("[%08lx] ", pc);
 863 #elif defined(SH)
 864         long pc;
 865         if (upeek(tcp, 4*REG_PC, &pc) < 0) {
 866                 tprints("[????????] ");
 867                 return;
 868         }
 869         tprintf("[%08lx] ", pc);
 870 #elif defined(SH64)
 871         long pc;
 872         if (upeek(tcp, REG_PC, &pc) < 0) {
 873                 tprints("[????????????????] ");
 874                 return;
 875         }
 876         tprintf("[%08lx] ", pc);
 877 #elif defined(ARM)
 878         tprintf("[%08lx] ", arm_regs.ARM_pc);
 879 #elif defined(AARCH64)
 880         /* tprintf("[%016lx] ", aarch64_regs.regs[???]); */
 881 #elif defined(AVR32)
 882         tprintf("[%08lx] ", avr32_regs.pc);
 883 #elif defined(BFIN)
 884         long pc;
 885         if (upeek(tcp, PT_PC, &pc) < 0) {
 886                 PRINTBADPC;
 887                 return;
 888         }
 889         tprintf("[%08lx] ", pc);
 890 #elif defined(CRISV10)
 891         long pc;
 892         if (upeek(tcp, 4*PT_IRP, &pc) < 0) {
 893                 PRINTBADPC;
 894                 return;
 895         }
 896         tprintf("[%08lx] ", pc);
 897 #elif defined(CRISV32)
 898         long pc;
 899         if (upeek(tcp, 4*PT_ERP, &pc) < 0) {
 900                 PRINTBADPC;
 901                 return;
 902         }
 903         tprintf("[%08lx] ", pc);
 904 #elif defined(TILE)
 905 # ifdef _LP64
 906         tprintf("[%016lx] ", (unsigned long) tile_regs.pc);
 907 # else
 908         tprintf("[%08lx] ", (unsigned long) tile_regs.pc);
 909 # endif
 910 #elif defined(OR1K)
 911         tprintf("[%08lx] ", or1k_regs.pc);
 912 #endif /* architecture */
 913 }
 914
 915 /* Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 916  * The shuffling should be reversible: shuffle_scno(shuffle_scno(n)) == n.
 917  */
 918 #if defined(ARM) /* So far only ARM needs this */
 919 static long
 920 shuffle_scno(unsigned long scno)
 921 {
 922         if (scno <= ARM_LAST_ORDINARY_SYSCALL)
 923                 return scno;
 924
 925         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 926         if (scno == 0x000ffff0)
 927                 return ARM_LAST_ORDINARY_SYSCALL+1;
 928         if (scno == ARM_LAST_ORDINARY_SYSCALL+1)
 929                 return 0x000ffff0;
 930
 931         /* Is it ARM specific syscall?
 932          * Swap with [LAST_ORDINARY+2, LAST_ORDINARY+2 + LAST_SPECIAL] range.
 933          */
 934         if (scno >= 0x000f0000
 935          && scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL
 936         ) {
 937                 return scno - 0x000f0000 + (ARM_LAST_ORDINARY_SYSCALL+2);
 938         }
 939         if (/* scno >= ARM_LAST_ORDINARY_SYSCALL+2 - always true */ 1
 940          && scno <= (ARM_LAST_ORDINARY_SYSCALL+2) + ARM_LAST_SPECIAL_SYSCALL
 941         ) {
 942                 return scno + 0x000f0000 - (ARM_LAST_ORDINARY_SYSCALL+2);
 943         }
 944
 945         return scno;
 946 }
 947 #else
 948 # define shuffle_scno(scno) ((long)(scno))
 949 #endif
 950
 951 static char*
 952 undefined_scno_name(struct tcb *tcp)
 953 {
 954         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
 955
 956         sprintf(buf, "syscall_%lu", shuffle_scno(tcp->scno));
 957         return buf;
 958 }
 959
 960 #ifndef get_regs
 961 long get_regs_error;
 962 void
 963 get_regs(pid_t pid)
 964 {
 965 # if defined(AVR32)
 966         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &avr32_regs);
 967 # elif defined(I386)
 968         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (long) &i386_regs);
 969 # elif defined(X86_64) || defined(X32)
 970         /*
 971          * PTRACE_GETREGSET was introduced in 2.6.33.
 972          * Let's be paranoid and require a bit later kernel.
 973          */
 974         if (os_release >= KERNEL_VERSION(2,6,35)) {
 975                 /*x86_io.iov_base = &x86_regs_union; - already is */
 976                 x86_io.iov_len = sizeof(x86_regs_union);
 977                 get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, (long) &x86_io);
 978         } else {
 979                 /* Use old method, with heuristical detection of 32-bitness */
 980                 x86_io.iov_len = sizeof(x86_64_regs);
 981                 get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (long) &x86_64_regs);
 982                 if (!get_regs_error && x86_64_regs.cs == 0x23) {
 983                         x86_io.iov_len = sizeof(i386_regs);
 984                         /*
 985                          * The order is important: i386_regs and x86_64_regs
 986                          * are overlaid in memory!
 987                          */
 988                         i386_regs.ebx = x86_64_regs.rbx;
 989                         i386_regs.ecx = x86_64_regs.rcx;
 990                         i386_regs.edx = x86_64_regs.rdx;
 991                         i386_regs.esi = x86_64_regs.rsi;
 992                         i386_regs.edi = x86_64_regs.rdi;
 993                         i386_regs.ebp = x86_64_regs.rbp;
 994                         i386_regs.eax = x86_64_regs.rax;
 995                         /*i386_regs.xds = x86_64_regs.ds; unused by strace */
 996                         /*i386_regs.xes = x86_64_regs.es; ditto... */
 997                         /*i386_regs.xfs = x86_64_regs.fs;*/
 998                         /*i386_regs.xgs = x86_64_regs.gs;*/
 999                         i386_regs.orig_eax = x86_64_regs.orig_rax;
1000                         i386_regs.eip = x86_64_regs.rip;
1001                         /*i386_regs.xcs = x86_64_regs.cs;*/
1002                         /*i386_regs.eflags = x86_64_regs.eflags;*/
1003                         i386_regs.esp = x86_64_regs.rsp;
1004                         /*i386_regs.xss = x86_64_regs.ss;*/
1005                 }
1006         }
1007 # elif defined(ARM)
1008         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (void *)&arm_regs);
1009 # elif defined(AARCH64)
1010         /*aarch64_io.iov_base = &arm_regs_union; - already is */
1011         aarch64_io.iov_len = sizeof(arm_regs_union);
1012         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, (void *)&aarch64_io);
1013 #  if 0
1014         /* Paranoia checks */
1015         if (get_regs_error)
1016                 return;
1017         switch (aarch64_io.iov_len) {
1018                 case sizeof(aarch64_regs):
1019                         /* We are in 64-bit mode */
1020                         break;
1021                 case sizeof(arm_regs):
1022                         /* We are in 32-bit mode */
1023                         break;
1024                 default:
1025                         get_regs_error = -1;
1026                         break;
1027         }
1028 #  endif
1029 # elif defined(SPARC) || defined(SPARC64)
1030         get_regs_error = ptrace(PTRACE_GETREGS, pid, (char *)&sparc_regs, 0);
1031 # elif defined(TILE)
1032         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (long) &tile_regs);
1033 # elif defined(OR1K)
1034         or1k_io.iov_len = sizeof(or1k_regs);
1035         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &or1k_io);
1036 # endif
1037 }
1038 #endif
1039
1040 /* Returns:
1041  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1042  * 1: ok, continue in trace_syscall_entering().
1043  * other: error, trace_syscall_entering() should print error indicator
1044  *    ("????" etc) and bail out.
1045  */
1046 static int
1047 get_scno(struct tcb *tcp)
1048 {
1049         long scno = 0;
1050
1051 #if defined(S390) || defined(S390X)
1052         if (upeek(tcp, PT_GPR2, &syscall_mode) < 0)
1053                 return -1;
1054
1055         if (syscall_mode != -ENOSYS) {
1056                 /*
1057                  * Since kernel version 2.5.44 the scno gets passed in gpr2.
1058                  */
1059                 scno = syscall_mode;
1060         } else {
1061                 /*
1062                  * Old style of "passing" the scno via the SVC instruction.
1063                  */
1064                 long psw;
1065                 long opcode, offset_reg, tmp;
1066                 void *svc_addr;
1067                 static const int gpr_offset[16] = {
1068                                 PT_GPR0,  PT_GPR1,  PT_ORIGGPR2, PT_GPR3,
1069                                 PT_GPR4,  PT_GPR5,  PT_GPR6,     PT_GPR7,
1070                                 PT_GPR8,  PT_GPR9,  PT_GPR10,    PT_GPR11,
1071                                 PT_GPR12, PT_GPR13, PT_GPR14,    PT_GPR15
1072                 };
1073
1074                 if (upeek(tcp, PT_PSWADDR, &psw) < 0)
1075                         return -1;
1076                 errno = 0;
1077                 opcode = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)(psw - sizeof(long)), 0);
1078                 if (errno) {
1079                         perror_msg("%s", "peektext(psw-oneword)");
1080                         return -1;
1081                 }
1082
1083                 /*
1084                  *  We have to check if the SVC got executed directly or via an
1085                  *  EXECUTE instruction. In case of EXECUTE it is necessary to do
1086                  *  instruction decoding to derive the system call number.
1087                  *  Unfortunately the opcode sizes of EXECUTE and SVC are differently,
1088                  *  so that this doesn't work if a SVC opcode is part of an EXECUTE
1089                  *  opcode. Since there is no way to find out the opcode size this
1090                  *  is the best we can do...
1091                  */
1092                 if ((opcode & 0xff00) == 0x0a00) {
1093                         /* SVC opcode */
1094                         scno = opcode & 0xff;
1095                 }
1096                 else {
1097                         /* SVC got executed by EXECUTE instruction */
1098
1099                         /*
1100                          *  Do instruction decoding of EXECUTE. If you really want to
1101                          *  understand this, read the Principles of Operations.
1102                          */
1103                         svc_addr = (void *) (opcode & 0xfff);
1104
1105                         tmp = 0;
1106                         offset_reg = (opcode & 0x000f0000) >> 16;
1107                         if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
1108                                 return -1;
1109                         svc_addr += tmp;
1110
1111                         tmp = 0;
1112                         offset_reg = (opcode & 0x0000f000) >> 12;
1113                         if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
1114                                 return -1;
1115                         svc_addr += tmp;
1116
1117                         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, svc_addr, 0);
1118                         if (errno)
1119                                 return -1;
1120 # if defined(S390X)
1121                         scno >>= 48;
1122 # else
1123                         scno >>= 16;
1124 # endif
1125                         tmp = 0;
1126                         offset_reg = (opcode & 0x00f00000) >> 20;
1127                         if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
1128                                 return -1;
1129
1130                         scno = (scno | tmp) & 0xff;
1131                 }
1132         }
1133 #elif defined(POWERPC)
1134         if (upeek(tcp, sizeof(unsigned long)*PT_R0, &scno) < 0)
1135                 return -1;
1136 # ifdef POWERPC64
1137         /* TODO: speed up strace by not doing this at every syscall.
1138          * We only need to do it after execve.
1139          */
1140         int currpers;
1141         long val;
1142
1143         /* Check for 64/32 bit mode. */
1144         if (upeek(tcp, sizeof(unsigned long)*PT_MSR, &val) < 0)
1145                 return -1;
1146         /* SF is bit 0 of MSR */
1147         if (val < 0)
1148                 currpers = 0;
1149         else
1150                 currpers = 1;
1151         update_personality(tcp, currpers);
1152 # endif
1153 #elif defined(AVR32)
1154         scno = avr32_regs.r8;
1155 #elif defined(BFIN)
1156         if (upeek(tcp, PT_ORIG_P0, &scno))
1157                 return -1;
1158 #elif defined(I386)
1159         scno = i386_regs.orig_eax;
1160 #elif defined(X86_64) || defined(X32)
1161 # ifndef __X32_SYSCALL_BIT
1162 #  define __X32_SYSCALL_BIT     0x40000000
1163 # endif
1164         int currpers;
1165 # if 1
1166         /* GETREGSET of NT_PRSTATUS tells us regset size,
1167          * which unambiguously detects i386.
1168          *
1169          * Linux kernel distinguishes x86-64 and x32 processes
1170          * solely by looking at __X32_SYSCALL_BIT:
1171          * arch/x86/include/asm/compat.h::is_x32_task():
1172          * if (task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT)
1173          *         return true;
1174          */
1175         if (x86_io.iov_len == sizeof(i386_regs)) {
1176                 scno = i386_regs.orig_eax;
1177                 currpers = 1;
1178         } else {
1179                 scno = x86_64_regs.orig_rax;
1180                 currpers = 0;
1181                 if (scno & __X32_SYSCALL_BIT) {
1182                         scno -= __X32_SYSCALL_BIT;
1183                         currpers = 2;
1184                 }
1185         }
1186 # elif 0
1187         /* cs = 0x33 for long mode (native 64 bit and x32)
1188          * cs = 0x23 for compatibility mode (32 bit)
1189          * ds = 0x2b for x32 mode (x86-64 in 32 bit)
1190          */
1191         scno = x86_64_regs.orig_rax;
1192         switch (x86_64_regs.cs) {
1193                 case 0x23: currpers = 1; break;
1194                 case 0x33:
1195                         if (x86_64_regs.ds == 0x2b) {
1196                                 currpers = 2;
1197                                 scno &= ~__X32_SYSCALL_BIT;
1198                         } else
1199                                 currpers = 0;
1200                         break;
1201                 default:
1202                         fprintf(stderr, "Unknown value CS=0x%08X while "
1203                                  "detecting personality of process "
1204                                  "PID=%d\n", (int)x86_64_regs.cs, tcp->pid);
1205                         currpers = current_personality;
1206                         break;
1207         }
1208 # elif 0
1209         /* This version analyzes the opcode of a syscall instruction.
1210          * (int 0x80 on i386 vs. syscall on x86-64)
1211          * It works, but is too complicated, and strictly speaking, unreliable.
1212          */
1213         unsigned long call, rip = x86_64_regs.rip;
1214         /* sizeof(syscall) == sizeof(int 0x80) == 2 */
1215         rip -= 2;
1216         errno = 0;
1217         call = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)rip, (char *)0);
1218         if (errno)
1219                 fprintf(stderr, "ptrace_peektext failed: %s\n",
1220                                 strerror(errno));
1221         switch (call & 0xffff) {
1222                 /* x86-64: syscall = 0x0f 0x05 */
1223                 case 0x050f: currpers = 0; break;
1224                 /* i386: int 0x80 = 0xcd 0x80 */
1225                 case 0x80cd: currpers = 1; break;
1226                 default:
1227                         currpers = current_personality;
1228                         fprintf(stderr,
1229                                 "Unknown syscall opcode (0x%04X) while "
1230                                 "detecting personality of process "
1231                                 "PID=%d\n", (int)call, tcp->pid);
1232                         break;
1233         }
1234 # endif
1235
1236 # ifdef X32
1237         /* If we are built for a x32 system, then personality 0 is x32
1238          * (not x86_64), and stracing of x86_64 apps is not supported.
1239          * Stracing of i386 apps is still supported.
1240          */
1241         if (currpers == 0) {
1242                 fprintf(stderr, "syscall_%lu(...) in unsupported "
1243                                 "64-bit mode of process PID=%d\n",
1244                         scno, tcp->pid);
1245                 return 0;
1246         }
1247         currpers &= ~2; /* map 2,1 to 0,1 */
1248 # endif
1249         update_personality(tcp, currpers);
1250 #elif defined(IA64)
1251 #       define IA64_PSR_IS      ((long)1 << 34)
1252         long psr;
1253         if (upeek(tcp, PT_CR_IPSR, &psr) >= 0)
1254                 ia32 = (psr & IA64_PSR_IS) != 0;
1255         if (ia32) {
1256                 if (upeek(tcp, PT_R1, &scno) < 0)
1257                         return -1;
1258         } else {
1259                 if (upeek(tcp, PT_R15, &scno) < 0)
1260                         return -1;
1261         }
1262 #elif defined(AARCH64)
1263         switch (aarch64_io.iov_len) {
1264                 case sizeof(aarch64_regs):
1265                         /* We are in 64-bit mode */
1266                         scno = aarch64_regs.regs[8];
1267                         update_personality(tcp, 1);
1268                         break;
1269                 case sizeof(arm_regs):
1270                         /* We are in 32-bit mode */
1271                         scno = arm_regs.ARM_r7;
1272                         update_personality(tcp, 0);
1273                         break;
1274         }
1275 #elif defined(ARM)
1276         if (arm_regs.ARM_ip != 0) {
1277                 /* It is not a syscall entry */
1278                 fprintf(stderr, "pid %d stray syscall exit\n", tcp->pid);
1279                 tcp->flags |= TCB_INSYSCALL;
1280                 return 0;
1281         }
1282         /* Note: we support only 32-bit CPUs, not 26-bit */
1283
1284         if (arm_regs.ARM_cpsr & 0x20) {
1285                 /* Thumb mode */
1286                 scno = arm_regs.ARM_r7;
1287         } else {
1288                 /* ARM mode */
1289                 errno = 0;
1290                 scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(arm_regs.ARM_pc - 4), NULL);
1291                 if (errno)
1292                         return -1;
1293
1294                 /* EABI syscall convention? */
1295                 if (scno == 0xef000000) {
1296                         scno = arm_regs.ARM_r7; /* yes */
1297                 } else {
1298                         if ((scno & 0x0ff00000) != 0x0f900000) {
1299                                 fprintf(stderr, "pid %d unknown syscall trap 0x%08lx\n",
1300                                         tcp->pid, scno);
1301                                 return -1;
1302                         }
1303                         /* Fixup the syscall number */
1304                         scno &= 0x000fffff;
1305                 }
1306         }
1307
1308         scno = shuffle_scno(scno);
1309 #elif defined(M68K)
1310         if (upeek(tcp, 4*PT_ORIG_D0, &scno) < 0)
1311                 return -1;
1312 #elif defined(LINUX_MIPSN32)
1313         unsigned long long regs[38];
1314
1315         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
1316                 return -1;
1317         mips_a3 = regs[REG_A3];
1318         mips_r2 = regs[REG_V0];
1319
1320         scno = mips_r2;
1321         if (!SCNO_IN_RANGE(scno)) {
1322                 if (mips_a3 == 0 || mips_a3 == -1) {
1323                         if (debug_flag)
1324                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1325                         return 0;
1326                 }
1327         }
1328 #elif defined(MIPS)
1329         if (upeek(tcp, REG_A3, &mips_a3) < 0)
1330                 return -1;
1331         if (upeek(tcp, REG_V0, &scno) < 0)
1332                 return -1;
1333
1334         if (!SCNO_IN_RANGE(scno)) {
1335                 if (mips_a3 == 0 || mips_a3 == -1) {
1336                         if (debug_flag)
1337                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1338                         return 0;
1339                 }
1340         }
1341 #elif defined(ALPHA)
1342         if (upeek(tcp, REG_A3, &alpha_a3) < 0)
1343                 return -1;
1344         if (upeek(tcp, REG_R0, &scno) < 0)
1345                 return -1;
1346
1347         /*
1348          * Do some sanity checks to figure out if it's
1349          * really a syscall entry
1350          */
1351         if (!SCNO_IN_RANGE(scno)) {
1352                 if (alpha_a3 == 0 || alpha_a3 == -1) {
1353                         if (debug_flag)
1354                                 fprintf(stderr, "stray syscall exit: r0 = %ld\n", scno);
1355                         return 0;
1356                 }
1357         }
1358 #elif defined(SPARC) || defined(SPARC64)
1359         /* Disassemble the syscall trap. */
1360         /* Retrieve the syscall trap instruction. */
1361         unsigned long trap;
1362         errno = 0;
1363 # if defined(SPARC64)
1364         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.tpc, 0);
1365         trap >>= 32;
1366 # else
1367         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.pc, 0);
1368 # endif
1369         if (errno)
1370                 return -1;
1371
1372         /* Disassemble the trap to see what personality to use. */
1373         switch (trap) {
1374         case 0x91d02010:
1375                 /* Linux/SPARC syscall trap. */
1376                 update_personality(tcp, 0);
1377                 break;
1378         case 0x91d0206d:
1379                 /* Linux/SPARC64 syscall trap. */
1380                 update_personality(tcp, 2);
1381                 break;
1382         case 0x91d02000:
1383                 /* SunOS syscall trap. (pers 1) */
1384                 fprintf(stderr, "syscall: SunOS no support\n");
1385                 return -1;
1386         case 0x91d02008:
1387                 /* Solaris 2.x syscall trap. (per 2) */
1388                 update_personality(tcp, 1);
1389                 break;
1390         case 0x91d02009:
1391                 /* NetBSD/FreeBSD syscall trap. */
1392                 fprintf(stderr, "syscall: NetBSD/FreeBSD not supported\n");
1393                 return -1;
1394         case 0x91d02027:
1395                 /* Solaris 2.x gettimeofday */
1396                 update_personality(tcp, 1);
1397                 break;
1398         default:
1399 # if defined(SPARC64)
1400                 fprintf(stderr, "syscall: unknown syscall trap %08lx %016lx\n", trap, sparc_regs.tpc);
1401 # else
1402                 fprintf(stderr, "syscall: unknown syscall trap %08lx %08lx\n", trap, sparc_regs.pc);
1403 # endif
1404                 return -1;
1405         }
1406
1407         /* Extract the system call number from the registers. */
1408         if (trap == 0x91d02027)
1409                 scno = 156;
1410         else
1411                 scno = sparc_regs.u_regs[U_REG_G1];
1412         if (scno == 0) {
1413                 scno = sparc_regs.u_regs[U_REG_O0];
1414                 memmove(&sparc_regs.u_regs[U_REG_O0], &sparc_regs.u_regs[U_REG_O1], 7*sizeof(sparc_regs.u_regs[0]));
1415         }
1416 #elif defined(HPPA)
1417         if (upeek(tcp, PT_GR20, &scno) < 0)
1418                 return -1;
1419 #elif defined(SH)
1420         /*
1421          * In the new syscall ABI, the system call number is in R3.
1422          */
1423         if (upeek(tcp, 4*(REG_REG0+3), &scno) < 0)
1424                 return -1;
1425
1426         if (scno < 0) {
1427                 /* Odd as it may seem, a glibc bug has been known to cause
1428                    glibc to issue bogus negative syscall numbers.  So for
1429                    our purposes, make strace print what it *should* have been */
1430                 long correct_scno = (scno & 0xff);
1431                 if (debug_flag)
1432                         fprintf(stderr,
1433                                 "Detected glibc bug: bogus system call"
1434                                 " number = %ld, correcting to %ld\n",
1435                                 scno,
1436                                 correct_scno);
1437                 scno = correct_scno;
1438         }
1439 #elif defined(SH64)
1440         if (upeek(tcp, REG_SYSCALL, &scno) < 0)
1441                 return -1;
1442         scno &= 0xFFFF;
1443 #elif defined(CRISV10) || defined(CRISV32)
1444         if (upeek(tcp, 4*PT_R9, &scno) < 0)
1445                 return -1;
1446 #elif defined(TILE)
1447         int currpers;
1448         scno = tile_regs.regs[10];
1449 # ifdef __tilepro__
1450         currpers = 1;
1451 # else
1452 #  ifndef PT_FLAGS_COMPAT
1453 #   define PT_FLAGS_COMPAT 0x10000  /* from Linux 3.8 on */
1454 #  endif
1455         if (tile_regs.flags & PT_FLAGS_COMPAT)
1456                 currpers = 1;
1457         else
1458                 currpers = 0;
1459 # endif
1460         update_personality(tcp, currpers);
1461 #elif defined(MICROBLAZE)
1462         if (upeek(tcp, 0, &scno) < 0)
1463                 return -1;
1464 #elif defined(OR1K)
1465         scno = or1k_regs.gpr[11];
1466 #endif
1467
1468         tcp->scno = scno;
1469         if (SCNO_IS_VALID(tcp->scno)) {
1470                 tcp->s_ent = &sysent[scno];
1471                 tcp->qual_flg = qual_flags[scno];
1472         } else {
1473                 static const struct_sysent unknown = {
1474                         .nargs = MAX_ARGS,
1475                         .sys_flags = 0,
1476                         .sys_func = printargs,
1477                         .sys_name = "unknown", /* not used */
1478                 };
1479                 tcp->s_ent = &unknown;
1480                 tcp->qual_flg = UNDEFINED_SCNO | QUAL_RAW | DEFAULT_QUAL_FLAGS;
1481         }
1482         return 1;
1483 }
1484
1485 /* Called at each syscall entry.
1486  * Returns:
1487  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1488  * 1: ok, continue in trace_syscall_entering().
1489  * other: error, trace_syscall_entering() should print error indicator
1490  *    ("????" etc) and bail out.
1491  */
1492 static int
1493 syscall_fixup_on_sysenter(struct tcb *tcp)
1494 {
1495         /* A common case of "not a syscall entry" is post-execve SIGTRAP */
1496 #if defined(I386)
1497         if (i386_regs.eax != -ENOSYS) {
1498                 if (debug_flag)
1499                         fprintf(stderr, "not a syscall entry (eax = %ld)\n", i386_regs.eax);
1500                 return 0;
1501         }
1502 #elif defined(X86_64) || defined(X32)
1503         {
1504                 long rax;
1505                 if (x86_io.iov_len == sizeof(i386_regs)) {
1506                         /* Sign extend from 32 bits */
1507                         rax = (int32_t)i386_regs.eax;
1508                 } else {
1509                         /* Note: in X32 build, this truncates 64 to 32 bits */
1510                         rax = x86_64_regs.rax;
1511                 }
1512                 if (rax != -ENOSYS) {
1513                         if (debug_flag)
1514                                 fprintf(stderr, "not a syscall entry (rax = %ld)\n", rax);
1515                         return 0;
1516                 }
1517         }
1518 #elif defined(S390) || defined(S390X)
1519         /* TODO: we already fetched PT_GPR2 in get_scno
1520          * and stored it in syscall_mode, reuse it here
1521          * instead of re-fetching?
1522          */
1523         if (upeek(tcp, PT_GPR2, &gpr2) < 0)
1524                 return -1;
1525         if (syscall_mode != -ENOSYS)
1526                 syscall_mode = tcp->scno;
1527         if (gpr2 != syscall_mode) {
1528                 if (debug_flag)
1529                         fprintf(stderr, "not a syscall entry (gpr2 = %ld)\n", gpr2);
1530                 return 0;
1531         }
1532 #elif defined(M68K)
1533         /* TODO? Eliminate upeek's in arches below like we did in x86 */
1534         if (upeek(tcp, 4*PT_D0, &m68k_d0) < 0)
1535                 return -1;
1536         if (m68k_d0 != -ENOSYS) {
1537                 if (debug_flag)
1538                         fprintf(stderr, "not a syscall entry (d0 = %ld)\n", m68k_d0);
1539                 return 0;
1540         }
1541 #elif defined(IA64)
1542         if (upeek(tcp, PT_R10, &ia64_r10) < 0)
1543                 return -1;
1544         if (upeek(tcp, PT_R8, &ia64_r8) < 0)
1545                 return -1;
1546         if (ia32 && ia64_r8 != -ENOSYS) {
1547                 if (debug_flag)
1548                         fprintf(stderr, "not a syscall entry (r8 = %ld)\n", ia64_r8);
1549                 return 0;
1550         }
1551 #elif defined(CRISV10) || defined(CRISV32)
1552         if (upeek(tcp, 4*PT_R10, &cris_r10) < 0)
1553                 return -1;
1554         if (cris_r10 != -ENOSYS) {
1555                 if (debug_flag)
1556                         fprintf(stderr, "not a syscall entry (r10 = %ld)\n", cris_r10);
1557                 return 0;
1558         }
1559 #elif defined(MICROBLAZE)
1560         if (upeek(tcp, 3 * 4, &microblaze_r3) < 0)
1561                 return -1;
1562         if (microblaze_r3 != -ENOSYS) {
1563                 if (debug_flag)
1564                         fprintf(stderr, "not a syscall entry (r3 = %ld)\n", microblaze_r3);
1565                 return 0;
1566         }
1567 #endif
1568         return 1;
1569 }
1570
1571 static void
1572 internal_fork(struct tcb *tcp)
1573 {
1574 #if defined S390 || defined S390X || defined CRISV10 || defined CRISV32
1575 # define ARG_FLAGS      1
1576 #else
1577 # define ARG_FLAGS      0
1578 #endif
1579 #ifndef CLONE_UNTRACED
1580 # define CLONE_UNTRACED 0x00800000
1581 #endif
1582         if ((ptrace_setoptions
1583             & (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
1584            == (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
1585                 return;
1586
1587         if (!followfork)
1588                 return;
1589
1590         if (entering(tcp)) {
1591                 /*
1592                  * We won't see the new child if clone is called with
1593                  * CLONE_UNTRACED, so we keep the same logic with that option
1594                  * and don't trace it.
1595                  */
1596                 if ((tcp->s_ent->sys_func == sys_clone)
1597                  && (tcp->u_arg[ARG_FLAGS] & CLONE_UNTRACED)
1598                 )
1599                         return;
1600                 setbpt(tcp);
1601         } else {
1602                 if (tcp->flags & TCB_BPTSET)
1603                         clearbpt(tcp);
1604         }
1605 }
1606
1607 #if defined(TCB_WAITEXECVE)
1608 static void
1609 internal_exec(struct tcb *tcp)
1610 {
1611         /* Maybe we have post-execve SIGTRAP suppressed? */
1612         if (ptrace_setoptions & PTRACE_O_TRACEEXEC)
1613                 return; /* yes, no need to do anything */
1614
1615         if (exiting(tcp) && syserror(tcp))
1616                 /* Error in execve, no post-execve SIGTRAP expected */
1617                 tcp->flags &= ~TCB_WAITEXECVE;
1618         else
1619                 tcp->flags |= TCB_WAITEXECVE;
1620 }
1621 #endif
1622
1623 static void
1624 syscall_fixup_for_fork_exec(struct tcb *tcp)
1625 {
1626         /*
1627          * We must always trace a few critical system calls in order to
1628          * correctly support following forks in the presence of tracing
1629          * qualifiers.
1630          */
1631         int (*func)();
1632
1633         func = tcp->s_ent->sys_func;
1634
1635         if (   sys_fork == func
1636             || sys_vfork == func
1637             || sys_clone == func
1638            ) {
1639                 internal_fork(tcp);
1640                 return;
1641         }
1642
1643 #if defined(TCB_WAITEXECVE)
1644         if (   sys_execve == func
1645 # if defined(SPARC) || defined(SPARC64)
1646             || sys_execv == func
1647 # endif
1648            ) {
1649                 internal_exec(tcp);
1650                 return;
1651         }
1652 #endif
1653 }
1654
1655 /* Return -1 on error or 1 on success (never 0!) */
1656 static int
1657 get_syscall_args(struct tcb *tcp)
1658 {
1659         int i, nargs;
1660
1661         nargs = tcp->s_ent->nargs;
1662
1663 #if defined(S390) || defined(S390X)
1664         for (i = 0; i < nargs; ++i)
1665                 if (upeek(tcp, i==0 ? PT_ORIGGPR2 : PT_GPR2 + i*sizeof(long), &tcp->u_arg[i]) < 0)
1666                         return -1;
1667 #elif defined(ALPHA)
1668         for (i = 0; i < nargs; ++i)
1669                 if (upeek(tcp, REG_A0+i, &tcp->u_arg[i]) < 0)
1670                         return -1;
1671 #elif defined(IA64)
1672         if (!ia32) {
1673                 unsigned long *out0, cfm, sof, sol;
1674                 long rbs_end;
1675                 /* be backwards compatible with kernel < 2.4.4... */
1676 #               ifndef PT_RBS_END
1677 #                 define PT_RBS_END     PT_AR_BSP
1678 #               endif
1679
1680                 if (upeek(tcp, PT_RBS_END, &rbs_end) < 0)
1681                         return -1;
1682                 if (upeek(tcp, PT_CFM, (long *) &cfm) < 0)
1683                         return -1;
1684
1685                 sof = (cfm >> 0) & 0x7f;
1686                 sol = (cfm >> 7) & 0x7f;
1687                 out0 = ia64_rse_skip_regs((unsigned long *) rbs_end, -sof + sol);
1688
1689                 for (i = 0; i < nargs; ++i) {
1690                         if (umoven(tcp, (unsigned long) ia64_rse_skip_regs(out0, i),
1691                                    sizeof(long), (char *) &tcp->u_arg[i]) < 0)
1692                                 return -1;
1693                 }
1694         } else {
1695                 static const int argreg[MAX_ARGS] = { PT_R11 /* EBX = out0 */,
1696                                                       PT_R9  /* ECX = out1 */,
1697                                                       PT_R10 /* EDX = out2 */,
1698                                                       PT_R14 /* ESI = out3 */,
1699                                                       PT_R15 /* EDI = out4 */,
1700                                                       PT_R13 /* EBP = out5 */};
1701
1702                 for (i = 0; i < nargs; ++i) {
1703                         if (upeek(tcp, argreg[i], &tcp->u_arg[i]) < 0)
1704                                 return -1;
1705                         /* truncate away IVE sign-extension */
1706                         tcp->u_arg[i] &= 0xffffffff;
1707                 }
1708         }
1709 #elif defined(LINUX_MIPSN32) || defined(LINUX_MIPSN64)
1710         /* N32 and N64 both use up to six registers.  */
1711         unsigned long long regs[38];
1712
1713         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
1714                 return -1;
1715
1716         for (i = 0; i < nargs; ++i) {
1717                 tcp->u_arg[i] = regs[REG_A0 + i];
1718 # if defined(LINUX_MIPSN32)
1719                 tcp->ext_arg[i] = regs[REG_A0 + i];
1720 # endif
1721         }
1722 #elif defined(MIPS)
1723         if (nargs > 4) {
1724                 long sp;
1725
1726                 if (upeek(tcp, REG_SP, &sp) < 0)
1727                         return -1;
1728                 for (i = 0; i < 4; ++i)
1729                         if (upeek(tcp, REG_A0 + i, &tcp->u_arg[i]) < 0)
1730                                 return -1;
1731                 umoven(tcp, sp + 16, (nargs - 4) * sizeof(tcp->u_arg[0]),
1732                        (char *)(tcp->u_arg + 4));
1733         } else {
1734                 for (i = 0; i < nargs; ++i)
1735                         if (upeek(tcp, REG_A0 + i, &tcp->u_arg[i]) < 0)
1736                                 return -1;
1737         }
1738 #elif defined(POWERPC)
1739 # ifndef PT_ORIG_R3
1740 #  define PT_ORIG_R3 34
1741 # endif
1742         for (i = 0; i < nargs; ++i) {
1743                 if (upeek(tcp, (i==0) ?
1744                         (sizeof(unsigned long) * PT_ORIG_R3) :
1745                         ((i+PT_R3) * sizeof(unsigned long)),
1746                                 &tcp->u_arg[i]) < 0)
1747                         return -1;
1748         }
1749 #elif defined(SPARC) || defined(SPARC64)
1750         for (i = 0; i < nargs; ++i)
1751                 tcp->u_arg[i] = sparc_regs.u_regs[U_REG_O0 + i];
1752 #elif defined(HPPA)
1753         for (i = 0; i < nargs; ++i)
1754                 if (upeek(tcp, PT_GR26-4*i, &tcp->u_arg[i]) < 0)
1755                         return -1;
1756 #elif defined(ARM) || defined(AARCH64)
1757 # if defined(AARCH64)
1758         if (tcp->currpers == 1)
1759                 for (i = 0; i < nargs; ++i)
1760                         tcp->u_arg[i] = aarch64_regs.regs[i];
1761         else
1762 # endif
1763         for (i = 0; i < nargs; ++i)
1764                 tcp->u_arg[i] = arm_regs.uregs[i];
1765 #elif defined(AVR32)
1766         (void)i;
1767         (void)nargs;
1768         tcp->u_arg[0] = avr32_regs.r12;
1769         tcp->u_arg[1] = avr32_regs.r11;
1770         tcp->u_arg[2] = avr32_regs.r10;
1771         tcp->u_arg[3] = avr32_regs.r9;
1772         tcp->u_arg[4] = avr32_regs.r5;
1773         tcp->u_arg[5] = avr32_regs.r3;
1774 #elif defined(BFIN)
1775         static const int argreg[MAX_ARGS] = { PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5 };
1776
1777         for (i = 0; i < nargs; ++i)
1778                 if (upeek(tcp, argreg[i], &tcp->u_arg[i]) < 0)
1779                         return -1;
1780 #elif defined(SH)
1781         static const int syscall_regs[MAX_ARGS] = {
1782                 4 * (REG_REG0+4), 4 * (REG_REG0+5), 4 * (REG_REG0+6),
1783                 4 * (REG_REG0+7), 4 * (REG_REG0  ), 4 * (REG_REG0+1)
1784         };
1785
1786         for (i = 0; i < nargs; ++i)
1787                 if (upeek(tcp, syscall_regs[i], &tcp->u_arg[i]) < 0)
1788                         return -1;
1789 #elif defined(SH64)
1790         int i;
1791         /* Registers used by SH5 Linux system calls for parameters */
1792         static const int syscall_regs[MAX_ARGS] = { 2, 3, 4, 5, 6, 7 };
1793
1794         for (i = 0; i < nargs; ++i)
1795                 if (upeek(tcp, REG_GENERAL(syscall_regs[i]), &tcp->u_arg[i]) < 0)
1796                         return -1;
1797 #elif defined(I386)
1798         (void)i;
1799         (void)nargs;
1800         tcp->u_arg[0] = i386_regs.ebx;
1801         tcp->u_arg[1] = i386_regs.ecx;
1802         tcp->u_arg[2] = i386_regs.edx;
1803         tcp->u_arg[3] = i386_regs.esi;
1804         tcp->u_arg[4] = i386_regs.edi;
1805         tcp->u_arg[5] = i386_regs.ebp;
1806 #elif defined(X86_64) || defined(X32)
1807         (void)i;
1808         (void)nargs;
1809         if (x86_io.iov_len != sizeof(i386_regs)) {
1810                 /* x86-64 or x32 ABI */
1811                 tcp->u_arg[0] = x86_64_regs.rdi;
1812                 tcp->u_arg[1] = x86_64_regs.rsi;
1813                 tcp->u_arg[2] = x86_64_regs.rdx;
1814                 tcp->u_arg[3] = x86_64_regs.r10;
1815                 tcp->u_arg[4] = x86_64_regs.r8;
1816                 tcp->u_arg[5] = x86_64_regs.r9;
1817 #  ifdef X32
1818                 tcp->ext_arg[0] = x86_64_regs.rdi;
1819                 tcp->ext_arg[1] = x86_64_regs.rsi;
1820                 tcp->ext_arg[2] = x86_64_regs.rdx;
1821                 tcp->ext_arg[3] = x86_64_regs.r10;
1822                 tcp->ext_arg[4] = x86_64_regs.r8;
1823                 tcp->ext_arg[5] = x86_64_regs.r9;
1824 #  endif
1825         } else {
1826                 /* i386 ABI */
1827                 /* Zero-extend from 32 bits */
1828                 /* Use widen_to_long(tcp->u_arg[N]) in syscall handlers
1829                  * if you need to use *sign-extended* parameter.
1830                  */
1831                 tcp->u_arg[0] = (long)(uint32_t)i386_regs.ebx;
1832                 tcp->u_arg[1] = (long)(uint32_t)i386_regs.ecx;
1833                 tcp->u_arg[2] = (long)(uint32_t)i386_regs.edx;
1834                 tcp->u_arg[3] = (long)(uint32_t)i386_regs.esi;
1835                 tcp->u_arg[4] = (long)(uint32_t)i386_regs.edi;
1836                 tcp->u_arg[5] = (long)(uint32_t)i386_regs.ebp;
1837         }
1838 #elif defined(MICROBLAZE)
1839         for (i = 0; i < nargs; ++i)
1840                 if (upeek(tcp, (5 + i) * 4, &tcp->u_arg[i]) < 0)
1841                         return -1;
1842 #elif defined(CRISV10) || defined(CRISV32)
1843         static const int crisregs[MAX_ARGS] = {
1844                 4*PT_ORIG_R10, 4*PT_R11, 4*PT_R12,
1845                 4*PT_R13     , 4*PT_MOF, 4*PT_SRP
1846         };
1847
1848         for (i = 0; i < nargs; ++i)
1849                 if (upeek(tcp, crisregs[i], &tcp->u_arg[i]) < 0)
1850                         return -1;
1851 #elif defined(TILE)
1852         for (i = 0; i < nargs; ++i)
1853                 tcp->u_arg[i] = tile_regs.regs[i];
1854 #elif defined(M68K)
1855         for (i = 0; i < nargs; ++i)
1856                 if (upeek(tcp, (i < 5 ? i : i + 2)*4, &tcp->u_arg[i]) < 0)
1857                         return -1;
1858 #elif defined(OR1K)
1859         (void)nargs;
1860         for (i = 0; i < 6; ++i)
1861                 tcp->u_arg[i] = or1k_regs.gpr[3 + i];
1862 #else /* Other architecture (32bits specific) */
1863         for (i = 0; i < nargs; ++i)
1864                 if (upeek(tcp, i*4, &tcp->u_arg[i]) < 0)
1865                         return -1;
1866 #endif
1867         return 1;
1868 }
1869
1870 static int
1871 trace_syscall_entering(struct tcb *tcp)
1872 {
1873         int res, scno_good;
1874
1875 #if defined TCB_WAITEXECVE
1876         if (tcp->flags & TCB_WAITEXECVE) {
1877                 /* This is the post-execve SIGTRAP. */
1878                 tcp->flags &= ~TCB_WAITEXECVE;
1879                 return 0;
1880         }
1881 #endif
1882
1883         scno_good = res = (get_regs_error ? -1 : get_scno(tcp));
1884         if (res == 0)
1885                 return res;
1886         if (res == 1) {
1887                 res = syscall_fixup_on_sysenter(tcp);
1888                 if (res == 0)
1889                         return res;
1890                 if (res == 1)
1891                         res = get_syscall_args(tcp);
1892         }
1893
1894         if (res != 1) {
1895                 printleader(tcp);
1896                 if (scno_good != 1)
1897                         tprints("????" /* anti-trigraph gap */ "(");
1898                 else if (tcp->qual_flg & UNDEFINED_SCNO)
1899                         tprintf("%s(", undefined_scno_name(tcp));
1900                 else
1901                         tprintf("%s(", tcp->s_ent->sys_name);
1902                 /*
1903                  * " <unavailable>" will be added later by the code which
1904                  * detects ptrace errors.
1905                  */
1906                 goto ret;
1907         }
1908
1909 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
1910         while (1) {
1911 # ifdef SYS_socket_subcall
1912                 if (tcp->s_ent->sys_func == sys_socketcall) {
1913                         decode_socket_subcall(tcp);
1914                         break;
1915                 }
1916 # endif
1917 # ifdef SYS_ipc_subcall
1918                 if (tcp->s_ent->sys_func == sys_ipc) {
1919                         decode_ipc_subcall(tcp);
1920                         break;
1921                 }
1922 # endif
1923                 break;
1924         }
1925 #endif
1926
1927         if (need_fork_exec_workarounds)
1928                 syscall_fixup_for_fork_exec(tcp);
1929
1930         if (!(tcp->qual_flg & QUAL_TRACE)
1931          || (tracing_paths && !pathtrace_match(tcp))
1932         ) {
1933                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
1934                 return 0;
1935         }
1936
1937         tcp->flags &= ~TCB_FILTERED;
1938
1939         if (cflag == CFLAG_ONLY_STATS) {
1940                 res = 0;
1941                 goto ret;
1942         }
1943
1944         printleader(tcp);
1945         if (tcp->qual_flg & UNDEFINED_SCNO)
1946                 tprintf("%s(", undefined_scno_name(tcp));
1947         else
1948                 tprintf("%s(", tcp->s_ent->sys_name);
1949         if ((tcp->qual_flg & QUAL_RAW) && tcp->s_ent->sys_func != sys_exit)
1950                 res = printargs(tcp);
1951         else
1952                 res = tcp->s_ent->sys_func(tcp);
1953
1954         fflush(tcp->outf);
1955  ret:
1956         tcp->flags |= TCB_INSYSCALL;
1957         /* Measure the entrance time as late as possible to avoid errors. */
1958         if (Tflag || cflag)
1959                 gettimeofday(&tcp->etime, NULL);
1960         return res;
1961 }
1962
1963 /* Returns:
1964  * 1: ok, continue in trace_syscall_exiting().
1965  * -1: error, trace_syscall_exiting() should print error indicator
1966  *    ("????" etc) and bail out.
1967  */
1968 static int
1969 get_syscall_result(struct tcb *tcp)
1970 {
1971 #if defined(S390) || defined(S390X)
1972         if (upeek(tcp, PT_GPR2, &gpr2) < 0)
1973                 return -1;
1974 #elif defined(POWERPC)
1975 # define SO_MASK 0x10000000
1976         {
1977                 long flags;
1978                 if (upeek(tcp, sizeof(unsigned long)*PT_CCR, &flags) < 0)
1979                         return -1;
1980                 if (upeek(tcp, sizeof(unsigned long)*PT_R3, &ppc_result) < 0)
1981                         return -1;
1982                 if (flags & SO_MASK)
1983                         ppc_result = -ppc_result;
1984         }
1985 #elif defined(AVR32)
1986         /* already done by get_regs */
1987 #elif defined(BFIN)
1988         if (upeek(tcp, PT_R0, &bfin_r0) < 0)
1989                 return -1;
1990 #elif defined(I386)
1991         /* already done by get_regs */
1992 #elif defined(X86_64) || defined(X32)
1993         /* already done by get_regs */
1994 #elif defined(IA64)
1995 #       define IA64_PSR_IS      ((long)1 << 34)
1996         long psr;
1997         if (upeek(tcp, PT_CR_IPSR, &psr) >= 0)
1998                 ia32 = (psr & IA64_PSR_IS) != 0;
1999         if (upeek(tcp, PT_R8, &ia64_r8) < 0)
2000                 return -1;
2001         if (upeek(tcp, PT_R10, &ia64_r10) < 0)
2002                 return -1;
2003 #elif defined(ARM)
2004         /* already done by get_regs */
2005 #elif defined(AARCH64)
2006         /* register reading already done by get_regs */
2007
2008         /* Used to do this, but we did it on syscall entry already: */
2009         /* We are in 64-bit mode (personality 1) if register struct is aarch64_regs,
2010          * else it's personality 0.
2011          */
2012         /*update_personality(tcp, aarch64_io.iov_len == sizeof(aarch64_regs));*/
2013 #elif defined(M68K)
2014         if (upeek(tcp, 4*PT_D0, &m68k_d0) < 0)
2015                 return -1;
2016 #elif defined(LINUX_MIPSN32)
2017         unsigned long long regs[38];
2018
2019         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
2020                 return -1;
2021         mips_a3 = regs[REG_A3];
2022         mips_r2 = regs[REG_V0];
2023 #elif defined(MIPS)
2024         if (upeek(tcp, REG_A3, &mips_a3) < 0)
2025                 return -1;
2026         if (upeek(tcp, REG_V0, &mips_r2) < 0)
2027                 return -1;
2028 #elif defined(ALPHA)
2029         if (upeek(tcp, REG_A3, &alpha_a3) < 0)
2030                 return -1;
2031         if (upeek(tcp, REG_R0, &alpha_r0) < 0)
2032                 return -1;
2033 #elif defined(SPARC) || defined(SPARC64)
2034         /* already done by get_regs */
2035 #elif defined(HPPA)
2036         if (upeek(tcp, PT_GR28, &hppa_r28) < 0)
2037                 return -1;
2038 #elif defined(SH)
2039         /* new syscall ABI returns result in R0 */
2040         if (upeek(tcp, 4*REG_REG0, (long *)&sh_r0) < 0)
2041                 return -1;
2042 #elif defined(SH64)
2043         /* ABI defines result returned in r9 */
2044         if (upeek(tcp, REG_GENERAL(9), (long *)&sh64_r9) < 0)
2045                 return -1;
2046 #elif defined(CRISV10) || defined(CRISV32)
2047         if (upeek(tcp, 4*PT_R10, &cris_r10) < 0)
2048                 return -1;
2049 #elif defined(TILE)
2050         /* already done by get_regs */
2051 #elif defined(MICROBLAZE)
2052         if (upeek(tcp, 3 * 4, &microblaze_r3) < 0)
2053                 return -1;
2054 #elif defined(OR1K)
2055         /* already done by get_regs */
2056 #endif
2057         return 1;
2058 }
2059
2060 /* Called at each syscall exit */
2061 static void
2062 syscall_fixup_on_sysexit(struct tcb *tcp)
2063 {
2064 #if defined(S390) || defined(S390X)
2065         if (syscall_mode != -ENOSYS)
2066                 syscall_mode = tcp->scno;
2067         if ((tcp->flags & TCB_WAITEXECVE)
2068                  && (gpr2 == -ENOSYS || gpr2 == tcp->scno)) {
2069                 /*
2070                  * Return from execve.
2071                  * Fake a return value of zero.  We leave the TCB_WAITEXECVE
2072                  * flag set for the post-execve SIGTRAP to see and reset.
2073                  */
2074                 gpr2 = 0;
2075         }
2076 #endif
2077 }
2078
2079 /*
2080  * Check the syscall return value register value for whether it is
2081  * a negated errno code indicating an error, or a success return value.
2082  */
2083 static inline int
2084 is_negated_errno(unsigned long int val)
2085 {
2086         unsigned long int max = -(long int) nerrnos;
2087 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
2088         if (current_wordsize < sizeof(val)) {
2089                 val = (unsigned int) val;
2090                 max = (unsigned int) max;
2091         }
2092 #endif
2093         return val > max;
2094 }
2095
2096 #if defined(X32)
2097 static inline int
2098 is_negated_errno_x32(unsigned long long val)
2099 {
2100         unsigned long long max = -(long long) nerrnos;
2101         /*
2102          * current_wordsize is 4 even in personality 0 (native X32)
2103          * but truncation _must not_ be done in it.
2104          * can't check current_wordsize here!
2105          */
2106         if (current_personality != 0) {
2107                 val = (uint32_t) val;
2108                 max = (uint32_t) max;
2109         }
2110         return val > max;
2111 }
2112 #endif
2113
2114 /* Returns:
2115  * 1: ok, continue in trace_syscall_exiting().
2116  * -1: error, trace_syscall_exiting() should print error indicator
2117  *    ("????" etc) and bail out.
2118  */
2119 static void
2120 get_error(struct tcb *tcp)
2121 {
2122         int u_error = 0;
2123         int check_errno = 1;
2124         if (tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS) {
2125                 check_errno = 0;
2126         }
2127 #if defined(S390) || defined(S390X)
2128         if (check_errno && is_negated_errno(gpr2)) {
2129                 tcp->u_rval = -1;
2130                 u_error = -gpr2;
2131         }
2132         else {
2133                 tcp->u_rval = gpr2;
2134         }
2135 #elif defined(I386)
2136         if (check_errno && is_negated_errno(i386_regs.eax)) {
2137                 tcp->u_rval = -1;
2138                 u_error = -i386_regs.eax;
2139         }
2140         else {
2141                 tcp->u_rval = i386_regs.eax;
2142         }
2143 #elif defined(X86_64)
2144         long rax;
2145         if (x86_io.iov_len == sizeof(i386_regs)) {
2146                 /* Sign extend from 32 bits */
2147                 rax = (int32_t)i386_regs.eax;
2148         } else {
2149                 rax = x86_64_regs.rax;
2150         }
2151         if (check_errno && is_negated_errno(rax)) {
2152                 tcp->u_rval = -1;
2153                 u_error = -rax;
2154         }
2155         else {
2156                 tcp->u_rval = rax;
2157         }
2158 #elif defined(X32)
2159         /* In X32, return value is 64-bit (llseek uses one).
2160          * Using merely "long rax" would not work.
2161          */
2162         long long rax;
2163         if (x86_io.iov_len == sizeof(i386_regs)) {
2164                 /* Sign extend from 32 bits */
2165                 rax = (int32_t)i386_regs.eax;
2166         } else {
2167                 rax = x86_64_regs.rax;
2168         }
2169         /* Careful: is_negated_errno() works only on longs */
2170         if (check_errno && is_negated_errno_x32(rax)) {
2171                 tcp->u_rval = -1;
2172                 u_error = -rax;
2173         }
2174         else {
2175                 tcp->u_rval = rax; /* truncating */
2176                 tcp->u_lrval = rax;
2177         }
2178 #elif defined(IA64)
2179         if (ia32) {
2180                 int err;
2181
2182                 err = (int)ia64_r8;
2183                 if (check_errno && is_negated_errno(err)) {
2184                         tcp->u_rval = -1;
2185                         u_error = -err;
2186                 }
2187                 else {
2188                         tcp->u_rval = err;
2189                 }
2190         } else {
2191                 if (check_errno && ia64_r10) {
2192                         tcp->u_rval = -1;
2193                         u_error = ia64_r8;
2194                 } else {
2195                         tcp->u_rval = ia64_r8;
2196                 }
2197         }
2198 #elif defined(MIPS)
2199         if (check_errno && mips_a3) {
2200                 tcp->u_rval = -1;
2201                 u_error = mips_r2;
2202         } else {
2203                 tcp->u_rval = mips_r2;
2204 # if defined(LINUX_MIPSN32)
2205                 tcp->u_lrval = mips_r2;
2206 # endif
2207         }
2208 #elif defined(POWERPC)
2209         if (check_errno && is_negated_errno(ppc_result)) {
2210                 tcp->u_rval = -1;
2211                 u_error = -ppc_result;
2212         }
2213         else {
2214                 tcp->u_rval = ppc_result;
2215         }
2216 #elif defined(M68K)
2217         if (check_errno && is_negated_errno(m68k_d0)) {
2218                 tcp->u_rval = -1;
2219                 u_error = -m68k_d0;
2220         }
2221         else {
2222                 tcp->u_rval = m68k_d0;
2223         }
2224 #elif defined(ARM) || defined(AARCH64)
2225 # if defined(AARCH64)
2226         if (tcp->currpers == 1) {
2227                 if (check_errno && is_negated_errno(aarch64_regs.regs[0])) {
2228                         tcp->u_rval = -1;
2229                         u_error = -aarch64_regs.regs[0];
2230                 }
2231                 else {
2232                         tcp->u_rval = aarch64_regs.regs[0];
2233                 }
2234         }
2235         else
2236 # endif
2237         {
2238                 if (check_errno && is_negated_errno(arm_regs.ARM_r0)) {
2239                         tcp->u_rval = -1;
2240                         u_error = -arm_regs.ARM_r0;
2241                 }
2242                 else {
2243                         tcp->u_rval = arm_regs.ARM_r0;
2244                 }
2245         }
2246 #elif defined(AVR32)
2247         if (check_errno && avr32_regs.r12 && (unsigned) -avr32_regs.r12 < nerrnos) {
2248                 tcp->u_rval = -1;
2249                 u_error = -avr32_regs.r12;
2250         }
2251         else {
2252                 tcp->u_rval = avr32_regs.r12;
2253         }
2254 #elif defined(BFIN)
2255         if (check_errno && is_negated_errno(bfin_r0)) {
2256                 tcp->u_rval = -1;
2257                 u_error = -bfin_r0;
2258         } else {
2259                 tcp->u_rval = bfin_r0;
2260         }
2261 #elif defined(ALPHA)
2262         if (check_errno && alpha_a3) {
2263                 tcp->u_rval = -1;
2264                 u_error = alpha_r0;
2265         }
2266         else {
2267                 tcp->u_rval = alpha_r0;
2268         }
2269 #elif defined(SPARC)
2270         if (check_errno && sparc_regs.psr & PSR_C) {
2271                 tcp->u_rval = -1;
2272                 u_error = sparc_regs.u_regs[U_REG_O0];
2273         }
2274         else {
2275                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2276         }
2277 #elif defined(SPARC64)
2278         if (check_errno && sparc_regs.tstate & 0x1100000000UL) {
2279                 tcp->u_rval = -1;
2280                 u_error = sparc_regs.u_regs[U_REG_O0];
2281         }
2282         else {
2283                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2284         }
2285 #elif defined(HPPA)
2286         if (check_errno && is_negated_errno(hppa_r28)) {
2287                 tcp->u_rval = -1;
2288                 u_error = -hppa_r28;
2289         }
2290         else {
2291                 tcp->u_rval = hppa_r28;
2292         }
2293 #elif defined(SH)
2294         if (check_errno && is_negated_errno(sh_r0)) {
2295                 tcp->u_rval = -1;
2296                 u_error = -sh_r0;
2297         }
2298         else {
2299                 tcp->u_rval = sh_r0;
2300         }
2301 #elif defined(SH64)
2302         if (check_errno && is_negated_errno(sh64_r9)) {
2303                 tcp->u_rval = -1;
2304                 u_error = -sh64_r9;
2305         }
2306         else {
2307                 tcp->u_rval = sh64_r9;
2308         }
2309 #elif defined(CRISV10) || defined(CRISV32)
2310         if (check_errno && cris_r10 && (unsigned) -cris_r10 < nerrnos) {
2311                 tcp->u_rval = -1;
2312                 u_error = -cris_r10;
2313         }
2314         else {
2315                 tcp->u_rval = cris_r10;
2316         }
2317 #elif defined(TILE)
2318         /*
2319          * The standard tile calling convention returns the value (or negative
2320          * errno) in r0, and zero (or positive errno) in r1.
2321          * Until at least kernel 3.8, however, the r1 value is not reflected
2322          * in ptregs at this point, so we use r0 here.
2323          */
2324         if (check_errno && is_negated_errno(tile_regs.regs[0])) {
2325                 tcp->u_rval = -1;
2326                 u_error = -tile_regs.regs[0];
2327         } else {
2328                 tcp->u_rval = tile_regs.regs[0];
2329         }
2330 #elif defined(MICROBLAZE)
2331         if (check_errno && is_negated_errno(microblaze_r3)) {
2332                 tcp->u_rval = -1;
2333                 u_error = -microblaze_r3;
2334         }
2335         else {
2336                 tcp->u_rval = microblaze_r3;
2337         }
2338 #elif defined(OR1K)
2339         if (check_errno && is_negated_errno(or1k_regs.gpr[11])) {
2340                 tcp->u_rval = -1;
2341                 u_error = -or1k_regs.gpr[11];
2342         }
2343         else {
2344                 tcp->u_rval = or1k_regs.gpr[11];
2345         }
2346 #endif
2347         tcp->u_error = u_error;
2348 }
2349
2350 static void
2351 dumpio(struct tcb *tcp)
2352 {
2353         int (*func)();
2354
2355         if (syserror(tcp))
2356                 return;
2357         if ((unsigned long) tcp->u_arg[0] >= num_quals)
2358                 return;
2359         func = tcp->s_ent->sys_func;
2360         if (func == printargs)
2361                 return;
2362         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
2363                 if (func == sys_read ||
2364                     func == sys_pread ||
2365                     func == sys_recv ||
2366                     func == sys_recvfrom)
2367                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
2368                 else if (func == sys_readv)
2369                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2370                 return;
2371         }
2372         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
2373                 if (func == sys_write ||
2374                     func == sys_pwrite ||
2375                     func == sys_send ||
2376                     func == sys_sendto)
2377                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
2378                 else if (func == sys_writev)
2379                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2380                 return;
2381         }
2382 }
2383
2384 static int
2385 trace_syscall_exiting(struct tcb *tcp)
2386 {
2387         int sys_res;
2388         struct timeval tv;
2389         int res;
2390         long u_error;
2391
2392         /* Measure the exit time as early as possible to avoid errors. */
2393         if (Tflag || cflag)
2394                 gettimeofday(&tv, NULL);
2395
2396 #if SUPPORTED_PERSONALITIES > 1
2397         update_personality(tcp, tcp->currpers);
2398 #endif
2399         res = (get_regs_error ? -1 : get_syscall_result(tcp));
2400         if (res == 1) {
2401                 syscall_fixup_on_sysexit(tcp); /* never fails */
2402                 get_error(tcp); /* never fails */
2403                 if (need_fork_exec_workarounds)
2404                         syscall_fixup_for_fork_exec(tcp);
2405                 if (filtered(tcp))
2406                         goto ret;
2407         }
2408
2409         if (cflag) {
2410                 struct timeval t = tv;
2411                 count_syscall(tcp, &t);
2412                 if (cflag == CFLAG_ONLY_STATS) {
2413                         goto ret;
2414                 }
2415         }
2416
2417         /* If not in -ff mode, and printing_tcp != tcp,
2418          * then the log currently does not end with output
2419          * of _our syscall entry_, but with something else.
2420          * We need to say which syscall's return is this.
2421          *
2422          * Forced reprinting via TCB_REPRINT is used only by
2423          * "strace -ff -oLOG test/threaded_execve" corner case.
2424          * It's the only case when -ff mode needs reprinting.
2425          */
2426         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
2427                 tcp->flags &= ~TCB_REPRINT;
2428                 printleader(tcp);
2429                 if (tcp->qual_flg & UNDEFINED_SCNO)
2430                         tprintf("<... %s resumed> ", undefined_scno_name(tcp));
2431                 else
2432                         tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
2433         }
2434         printing_tcp = tcp;
2435
2436         if (res != 1) {
2437                 /* There was error in one of prior ptrace ops */
2438                 tprints(") ");
2439                 tabto();
2440                 tprints("= ? <unavailable>\n");
2441                 line_ended();
2442                 tcp->flags &= ~TCB_INSYSCALL;
2443                 return res;
2444         }
2445
2446         sys_res = 0;
2447         if (tcp->qual_flg & QUAL_RAW) {
2448                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
2449         } else {
2450         /* FIXME: not_failing_only (IOW, option -z) is broken:
2451          * failure of syscall is known only after syscall return.
2452          * Thus we end up with something like this on, say, ENOENT:
2453          *     open("doesnt_exist", O_RDONLY <unfinished ...>
2454          *     {next syscall decode}
2455          * whereas the intended result is that open(...) line
2456          * is not shown at all.
2457          */
2458                 if (not_failing_only && tcp->u_error)
2459                         goto ret;       /* ignore failed syscalls */
2460                 sys_res = tcp->s_ent->sys_func(tcp);
2461         }
2462
2463         tprints(") ");
2464         tabto();
2465         u_error = tcp->u_error;
2466         if (tcp->qual_flg & QUAL_RAW) {
2467                 if (u_error)
2468                         tprintf("= -1 (errno %ld)", u_error);
2469                 else
2470                         tprintf("= %#lx", tcp->u_rval);
2471         }
2472         else if (!(sys_res & RVAL_NONE) && u_error) {
2473                 switch (u_error) {
2474                 /* Blocked signals do not interrupt any syscalls.
2475                  * In this case syscalls don't return ERESTARTfoo codes.
2476                  *
2477                  * Deadly signals set to SIG_DFL interrupt syscalls
2478                  * and kill the process regardless of which of the codes below
2479                  * is returned by the interrupted syscall.
2480                  * In some cases, kernel forces a kernel-generated deadly
2481                  * signal to be unblocked and set to SIG_DFL (and thus cause
2482                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
2483                  * or SIGILL. (The alternative is to leave process spinning
2484                  * forever on the faulty instruction - not useful).
2485                  *
2486                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
2487                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
2488                  * but kernel will always restart them.
2489                  */
2490                 case ERESTARTSYS:
2491                         /* Most common type of signal-interrupted syscall exit code.
2492                          * The system call will be restarted with the same arguments
2493                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
2494                          */
2495                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
2496                         break;
2497                 case ERESTARTNOINTR:
2498                         /* Rare. For example, fork() returns this if interrupted.
2499                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
2500                          */
2501                         tprints("= ? ERESTARTNOINTR (To be restarted)");
2502                         break;
2503                 case ERESTARTNOHAND:
2504                         /* pause(), rt_sigsuspend() etc use this code.
2505                          * SA_RESTART is ignored (assumed not set):
2506                          * syscall won't restart (will return EINTR instead)
2507                          * even after signal with SA_RESTART set. However,
2508                          * after SIG_IGN or SIG_DFL signal it will restart
2509                          * (thus the name "restart only if has no handler").
2510                          */
2511                         tprints("= ? ERESTARTNOHAND (Interrupted by signal)");
2512                         break;
2513                 case ERESTART_RESTARTBLOCK:
2514                         /* Syscalls like nanosleep(), poll() which can't be
2515                          * restarted with their original arguments use this
2516                          * code. Kernel will execute restart_syscall() instead,
2517                          * which changes arguments before restarting syscall.
2518                          * SA_RESTART is ignored (assumed not set) similarly
2519                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
2520                          * since restart data is saved in "restart block"
2521                          * in task struct, and if signal handler uses a syscall
2522                          * which in turn saves another such restart block,
2523                          * old data is lost and restart becomes impossible)
2524                          */
2525                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
2526                         break;
2527                 default:
2528                         if (u_error < 0)
2529                                 tprintf("= -1 E??? (errno %ld)", u_error);
2530                         else if (u_error < nerrnos)
2531                                 tprintf("= -1 %s (%s)", errnoent[u_error],
2532                                         strerror(u_error));
2533                         else
2534                                 tprintf("= -1 ERRNO_%ld (%s)", u_error,
2535                                         strerror(u_error));
2536                         break;
2537                 }
2538                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2539                         tprintf(" (%s)", tcp->auxstr);
2540         }
2541         else {
2542                 if (sys_res & RVAL_NONE)
2543                         tprints("= ?");
2544                 else {
2545                         switch (sys_res & RVAL_MASK) {
2546                         case RVAL_HEX:
2547                                 tprintf("= %#lx", tcp->u_rval);
2548                                 break;
2549                         case RVAL_OCTAL:
2550                                 tprintf("= %#lo", tcp->u_rval);
2551                                 break;
2552                         case RVAL_UDECIMAL:
2553                                 tprintf("= %lu", tcp->u_rval);
2554                                 break;
2555                         case RVAL_DECIMAL:
2556                                 tprintf("= %ld", tcp->u_rval);
2557                                 break;
2558 #if defined(LINUX_MIPSN32) || defined(X32)
2559                         /*
2560                         case RVAL_LHEX:
2561                                 tprintf("= %#llx", tcp->u_lrval);
2562                                 break;
2563                         case RVAL_LOCTAL:
2564                                 tprintf("= %#llo", tcp->u_lrval);
2565                                 break;
2566                         */
2567                         case RVAL_LUDECIMAL:
2568                                 tprintf("= %llu", tcp->u_lrval);
2569                                 break;
2570                         /*
2571                         case RVAL_LDECIMAL:
2572                                 tprintf("= %lld", tcp->u_lrval);
2573                                 break;
2574                         */
2575 #endif
2576                         default:
2577                                 fprintf(stderr,
2578                                         "invalid rval format\n");
2579                                 break;
2580                         }
2581                 }
2582                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2583                         tprintf(" (%s)", tcp->auxstr);
2584         }
2585         if (Tflag) {
2586                 tv_sub(&tv, &tv, &tcp->etime);
2587                 tprintf(" <%ld.%06ld>",
2588                         (long) tv.tv_sec, (long) tv.tv_usec);
2589         }
2590         tprints("\n");
2591         dumpio(tcp);
2592         line_ended();
2593
2594  ret:
2595         tcp->flags &= ~TCB_INSYSCALL;
2596         return 0;
2597 }
2598
2599 int
2600 trace_syscall(struct tcb *tcp)
2601 {
2602         return exiting(tcp) ?
2603                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
2604 }