granicus.if.org Git - strace/blob - syscall.c

   1 /*
   2  * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
   3  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
   4  * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
   5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
   6  * Copyright (c) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
   7  *                     Linux for s390 port by D.J. Barrow
   8  *                    <barrow_dj@mail.yahoo.com,djbarrow@de.ibm.com>
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. The name of the author may not be used to endorse or promote products
  20  *    derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include "defs.h"
  35 #include <sys/param.h>
  36
  37 /* for struct iovec */
  38 #include <sys/uio.h>
  39
  40 #include "regs.h"
  41 #include "ptrace.h"
  42
  43 #if defined(SPARC64)
  44 # undef PTRACE_GETREGS
  45 # define PTRACE_GETREGS PTRACE_GETREGS64
  46 # undef PTRACE_SETREGS
  47 # define PTRACE_SETREGS PTRACE_SETREGS64
  48 #endif
  49
  50 #if defined SPARC64
  51 # include <asm/psrcompat.h>
  52 #elif defined SPARC
  53 # include <asm/psr.h>
  54 #endif
  55
  56 #ifdef IA64
  57 # include <asm/rse.h>
  58 #endif
  59
  60 #ifndef NT_PRSTATUS
  61 # define NT_PRSTATUS 1
  62 #endif
  63
  64 #ifndef NSIG
  65 # warning: NSIG is not defined, using 32
  66 # define NSIG 32
  67 #endif
  68
  69 #include "syscall.h"
  70
  71 /* Define these shorthand notations to simplify the syscallent files. */
  72 #define TD TRACE_DESC
  73 #define TF TRACE_FILE
  74 #define TI TRACE_IPC
  75 #define TN TRACE_NETWORK
  76 #define TP TRACE_PROCESS
  77 #define TS TRACE_SIGNAL
  78 #define TM TRACE_MEMORY
  79 #define NF SYSCALL_NEVER_FAILS
  80 #define MA MAX_ARGS
  81 #define SI STACKTRACE_INVALIDATE_CACHE
  82 #define SE STACKTRACE_CAPTURE_ON_ENTER
  83
  84 const struct_sysent sysent0[] = {
  85 #include "syscallent.h"
  86 };
  87
  88 #if SUPPORTED_PERSONALITIES > 1
  89 static const struct_sysent sysent1[] = {
  90 # include "syscallent1.h"
  91 };
  92 #endif
  93
  94 #if SUPPORTED_PERSONALITIES > 2
  95 static const struct_sysent sysent2[] = {
  96 # include "syscallent2.h"
  97 };
  98 #endif
  99
 100 /* Now undef them since short defines cause wicked namespace pollution. */
 101 #undef TD
 102 #undef TF
 103 #undef TI
 104 #undef TN
 105 #undef TP
 106 #undef TS
 107 #undef TM
 108 #undef NF
 109 #undef MA
 110 #undef SI
 111 #undef SE
 112
 113 /*
 114  * `ioctlent[012].h' files are automatically generated by the auxiliary
 115  * program `ioctlsort', such that the list is sorted by the `code' field.
 116  * This has the side-effect of resolving the _IO.. macros into
 117  * plain integers, eliminating the need to include here everything
 118  * in "/usr/include".
 119  */
 120
 121 const char *const errnoent0[] = {
 122 #include "errnoent.h"
 123 };
 124 const char *const signalent0[] = {
 125 #include "signalent.h"
 126 };
 127 const struct_ioctlent ioctlent0[] = {
 128 #include "ioctlent0.h"
 129 };
 130
 131 #if SUPPORTED_PERSONALITIES > 1
 132 static const char *const errnoent1[] = {
 133 # include "errnoent1.h"
 134 };
 135 static const char *const signalent1[] = {
 136 # include "signalent1.h"
 137 };
 138 static const struct_ioctlent ioctlent1[] = {
 139 # include "ioctlent1.h"
 140 };
 141 #endif
 142
 143 #if SUPPORTED_PERSONALITIES > 2
 144 static const char *const errnoent2[] = {
 145 # include "errnoent2.h"
 146 };
 147 static const char *const signalent2[] = {
 148 # include "signalent2.h"
 149 };
 150 static const struct_ioctlent ioctlent2[] = {
 151 # include "ioctlent2.h"
 152 };
 153 #endif
 154
 155 enum {
 156         nsyscalls0 = ARRAY_SIZE(sysent0)
 157 #if SUPPORTED_PERSONALITIES > 1
 158         , nsyscalls1 = ARRAY_SIZE(sysent1)
 159 # if SUPPORTED_PERSONALITIES > 2
 160         , nsyscalls2 = ARRAY_SIZE(sysent2)
 161 # endif
 162 #endif
 163 };
 164
 165 enum {
 166         nerrnos0 = ARRAY_SIZE(errnoent0)
 167 #if SUPPORTED_PERSONALITIES > 1
 168         , nerrnos1 = ARRAY_SIZE(errnoent1)
 169 # if SUPPORTED_PERSONALITIES > 2
 170         , nerrnos2 = ARRAY_SIZE(errnoent2)
 171 # endif
 172 #endif
 173 };
 174
 175 enum {
 176         nsignals0 = ARRAY_SIZE(signalent0)
 177 #if SUPPORTED_PERSONALITIES > 1
 178         , nsignals1 = ARRAY_SIZE(signalent1)
 179 # if SUPPORTED_PERSONALITIES > 2
 180         , nsignals2 = ARRAY_SIZE(signalent2)
 181 # endif
 182 #endif
 183 };
 184
 185 enum {
 186         nioctlents0 = ARRAY_SIZE(ioctlent0)
 187 #if SUPPORTED_PERSONALITIES > 1
 188         , nioctlents1 = ARRAY_SIZE(ioctlent1)
 189 # if SUPPORTED_PERSONALITIES > 2
 190         , nioctlents2 = ARRAY_SIZE(ioctlent2)
 191 # endif
 192 #endif
 193 };
 194
 195 #if SUPPORTED_PERSONALITIES > 1
 196 const struct_sysent *sysent = sysent0;
 197 const char *const *errnoent = errnoent0;
 198 const char *const *signalent = signalent0;
 199 const struct_ioctlent *ioctlent = ioctlent0;
 200 #endif
 201 unsigned nsyscalls = nsyscalls0;
 202 unsigned nerrnos = nerrnos0;
 203 unsigned nsignals = nsignals0;
 204 unsigned nioctlents = nioctlents0;
 205
 206 unsigned num_quals;
 207 qualbits_t *qual_vec[SUPPORTED_PERSONALITIES];
 208
 209 static const unsigned nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 210         nsyscalls0,
 211 #if SUPPORTED_PERSONALITIES > 1
 212         nsyscalls1,
 213 #endif
 214 #if SUPPORTED_PERSONALITIES > 2
 215         nsyscalls2,
 216 #endif
 217 };
 218 static const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 219         sysent0,
 220 #if SUPPORTED_PERSONALITIES > 1
 221         sysent1,
 222 #endif
 223 #if SUPPORTED_PERSONALITIES > 2
 224         sysent2,
 225 #endif
 226 };
 227
 228 enum {
 229         MAX_NSYSCALLS1 = (nsyscalls0
 230 #if SUPPORTED_PERSONALITIES > 1
 231                         > nsyscalls1 ? nsyscalls0 : nsyscalls1
 232 #endif
 233                         ),
 234         MAX_NSYSCALLS2 = (MAX_NSYSCALLS1
 235 #if SUPPORTED_PERSONALITIES > 2
 236                         > nsyscalls2 ? MAX_NSYSCALLS1 : nsyscalls2
 237 #endif
 238                         ),
 239         MAX_NSYSCALLS = MAX_NSYSCALLS2,
 240         /* We are ready for arches with up to 255 signals,
 241          * even though the largest known signo is on MIPS and it is 128.
 242          * The number of existing syscalls on all arches is
 243          * larger that 255 anyway, so it is just a pedantic matter.
 244          */
 245         MIN_QUALS = MAX_NSYSCALLS > 255 ? MAX_NSYSCALLS : 255
 246 };
 247
 248 #if SUPPORTED_PERSONALITIES > 1
 249 unsigned current_personality;
 250
 251 # ifndef current_wordsize
 252 unsigned current_wordsize;
 253 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 254         PERSONALITY0_WORDSIZE,
 255         PERSONALITY1_WORDSIZE,
 256 # if SUPPORTED_PERSONALITIES > 2
 257         PERSONALITY2_WORDSIZE,
 258 # endif
 259 };
 260 # endif
 261
 262 void
 263 set_personality(int personality)
 264 {
 265         nsyscalls = nsyscall_vec[personality];
 266         sysent = sysent_vec[personality];
 267
 268         switch (personality) {
 269         case 0:
 270                 errnoent = errnoent0;
 271                 nerrnos = nerrnos0;
 272                 ioctlent = ioctlent0;
 273                 nioctlents = nioctlents0;
 274                 signalent = signalent0;
 275                 nsignals = nsignals0;
 276                 break;
 277
 278         case 1:
 279                 errnoent = errnoent1;
 280                 nerrnos = nerrnos1;
 281                 ioctlent = ioctlent1;
 282                 nioctlents = nioctlents1;
 283                 signalent = signalent1;
 284                 nsignals = nsignals1;
 285                 break;
 286
 287 # if SUPPORTED_PERSONALITIES > 2
 288         case 2:
 289                 errnoent = errnoent2;
 290                 nerrnos = nerrnos2;
 291                 ioctlent = ioctlent2;
 292                 nioctlents = nioctlents2;
 293                 signalent = signalent2;
 294                 nsignals = nsignals2;
 295                 break;
 296 # endif
 297         }
 298
 299         current_personality = personality;
 300 # ifndef current_wordsize
 301         current_wordsize = personality_wordsize[personality];
 302 # endif
 303 }
 304
 305 static void
 306 update_personality(struct tcb *tcp, unsigned int personality)
 307 {
 308         if (personality == current_personality)
 309                 return;
 310         set_personality(personality);
 311
 312         if (personality == tcp->currpers)
 313                 return;
 314         tcp->currpers = personality;
 315
 316 # if defined(POWERPC64)
 317         if (!qflag) {
 318                 static const char *const names[] = {"64 bit", "32 bit"};
 319                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 320                         tcp->pid, names[personality]);
 321         }
 322 # elif defined(X86_64)
 323         if (!qflag) {
 324                 static const char *const names[] = {"64 bit", "32 bit", "x32"};
 325                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 326                         tcp->pid, names[personality]);
 327         }
 328 # elif defined(X32)
 329         if (!qflag) {
 330                 static const char *const names[] = {"x32", "32 bit"};
 331                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 332                         tcp->pid, names[personality]);
 333         }
 334 # elif defined(AARCH64)
 335         if (!qflag) {
 336                 static const char *const names[] = {"32-bit", "AArch64"};
 337                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 338                         tcp->pid, names[personality]);
 339         }
 340 # elif defined(TILE)
 341         if (!qflag) {
 342                 static const char *const names[] = {"64-bit", "32-bit"};
 343                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
 344                         tcp->pid, names[personality]);
 345         }
 346 # endif
 347 }
 348 #endif
 349
 350 static int qual_syscall(), qual_signal(), qual_desc();
 351
 352 static const struct qual_options {
 353         unsigned int bitflag;
 354         const char *option_name;
 355         int (*qualify)(const char *, int, int);
 356         const char *argument_name;
 357 } qual_options[] = {
 358         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
 359         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
 360         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
 361         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
 362         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
 363         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
 364         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
 365         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
 366         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
 367         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
 368         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
 369         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
 370         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
 371         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
 372         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
 373         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
 374         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
 375         { 0,            NULL,           NULL,           NULL            },
 376 };
 377
 378 static void
 379 reallocate_qual(const unsigned int n)
 380 {
 381         unsigned p;
 382         qualbits_t *qp;
 383         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 384                 qp = qual_vec[p] = realloc(qual_vec[p], n * sizeof(qualbits_t));
 385                 if (!qp)
 386                         die_out_of_memory();
 387                 memset(&qp[num_quals], 0, (n - num_quals) * sizeof(qualbits_t));
 388         }
 389         num_quals = n;
 390 }
 391
 392 static void
 393 qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
 394 {
 395         int p;
 396
 397         if (num_quals <= n)
 398                 reallocate_qual(n + 1);
 399
 400         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 401                 if (pers == p || pers < 0) {
 402                         if (not)
 403                                 qual_vec[p][n] &= ~bitflag;
 404                         else
 405                                 qual_vec[p][n] |= bitflag;
 406                 }
 407         }
 408 }
 409
 410 static int
 411 qual_syscall(const char *s, const unsigned int bitflag, const int not)
 412 {
 413         int p;
 414         unsigned int i;
 415         int rc = -1;
 416
 417         if (*s >= '0' && *s <= '9') {
 418                 i = string_to_uint(s);
 419                 if (i >= MAX_NSYSCALLS)
 420                         return -1;
 421                 qualify_one(i, bitflag, not, -1);
 422                 return 0;
 423         }
 424
 425         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 426                 for (i = 0; i < nsyscall_vec[p]; i++) {
 427                         if (sysent_vec[p][i].sys_name
 428                          && strcmp(s, sysent_vec[p][i].sys_name) == 0
 429                         ) {
 430                                 qualify_one(i, bitflag, not, p);
 431                                 rc = 0;
 432                         }
 433                 }
 434         }
 435
 436         return rc;
 437 }
 438
 439 static int
 440 qual_signal(const char *s, const unsigned int bitflag, const int not)
 441 {
 442         unsigned int i;
 443
 444         if (*s >= '0' && *s <= '9') {
 445                 int signo = string_to_uint(s);
 446                 if (signo < 0 || signo > 255)
 447                         return -1;
 448                 qualify_one(signo, bitflag, not, -1);
 449                 return 0;
 450         }
 451         if (strncasecmp(s, "SIG", 3) == 0)
 452                 s += 3;
 453         for (i = 0; i <= NSIG; i++) {
 454                 if (strcasecmp(s, signame(i) + 3) == 0) {
 455                         qualify_one(i, bitflag, not, -1);
 456                         return 0;
 457                 }
 458         }
 459         return -1;
 460 }
 461
 462 static int
 463 qual_desc(const char *s, const unsigned int bitflag, const int not)
 464 {
 465         if (*s >= '0' && *s <= '9') {
 466                 int desc = string_to_uint(s);
 467                 if (desc < 0 || desc > 0x7fff) /* paranoia */
 468                         return -1;
 469                 qualify_one(desc, bitflag, not, -1);
 470                 return 0;
 471         }
 472         return -1;
 473 }
 474
 475 static int
 476 lookup_class(const char *s)
 477 {
 478         if (strcmp(s, "file") == 0)
 479                 return TRACE_FILE;
 480         if (strcmp(s, "ipc") == 0)
 481                 return TRACE_IPC;
 482         if (strcmp(s, "network") == 0)
 483                 return TRACE_NETWORK;
 484         if (strcmp(s, "process") == 0)
 485                 return TRACE_PROCESS;
 486         if (strcmp(s, "signal") == 0)
 487                 return TRACE_SIGNAL;
 488         if (strcmp(s, "desc") == 0)
 489                 return TRACE_DESC;
 490         if (strcmp(s, "memory") == 0)
 491                 return TRACE_MEMORY;
 492         return -1;
 493 }
 494
 495 void
 496 qualify(const char *s)
 497 {
 498         const struct qual_options *opt;
 499         char *copy;
 500         const char *p;
 501         int not;
 502         unsigned int i;
 503
 504         if (num_quals == 0)
 505                 reallocate_qual(MIN_QUALS);
 506
 507         opt = &qual_options[0];
 508         for (i = 0; (p = qual_options[i].option_name); i++) {
 509                 unsigned int len = strlen(p);
 510                 if (strncmp(s, p, len) == 0 && s[len] == '=') {
 511                         opt = &qual_options[i];
 512                         s += len + 1;
 513                         break;
 514                 }
 515         }
 516         not = 0;
 517         if (*s == '!') {
 518                 not = 1;
 519                 s++;
 520         }
 521         if (strcmp(s, "none") == 0) {
 522                 not = 1 - not;
 523                 s = "all";
 524         }
 525         if (strcmp(s, "all") == 0) {
 526                 for (i = 0; i < num_quals; i++) {
 527                         qualify_one(i, opt->bitflag, not, -1);
 528                 }
 529                 return;
 530         }
 531         for (i = 0; i < num_quals; i++) {
 532                 qualify_one(i, opt->bitflag, !not, -1);
 533         }
 534         copy = strdup(s);
 535         if (!copy)
 536                 die_out_of_memory();
 537         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
 538                 int n;
 539                 if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
 540                         unsigned pers;
 541                         for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
 542                                 for (i = 0; i < nsyscall_vec[pers]; i++)
 543                                         if (sysent_vec[pers][i].sys_flags & n)
 544                                                 qualify_one(i, opt->bitflag, not, pers);
 545                         }
 546                         continue;
 547                 }
 548                 if (opt->qualify(p, opt->bitflag, not)) {
 549                         error_msg_and_die("invalid %s '%s'",
 550                                 opt->argument_name, p);
 551                 }
 552         }
 553         free(copy);
 554         return;
 555 }
 556
 557 #ifdef SYS_socket_subcall
 558 static void
 559 decode_socket_subcall(struct tcb *tcp)
 560 {
 561         unsigned long addr;
 562         unsigned int n;
 563
 564         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_socket_nsubcalls)
 565                 return;
 566
 567         tcp->scno = SYS_socket_subcall + tcp->u_arg[0];
 568         tcp->qual_flg = qual_flags[tcp->scno];
 569         tcp->s_ent = &sysent[tcp->scno];
 570         addr = tcp->u_arg[1];
 571         n = tcp->s_ent->nargs;
 572         if (sizeof(tcp->u_arg[0]) == current_wordsize) {
 573                 memset(tcp->u_arg, 0, n * sizeof(tcp->u_arg[0]));
 574                 (void) umoven(tcp, addr, n * sizeof(tcp->u_arg[0]), tcp->u_arg);
 575         } else {
 576                 unsigned int args[n];
 577                 unsigned int i;
 578
 579                 memset(args, 0, sizeof(args));
 580                 (void) umove(tcp, addr, &args);
 581                 for (i = 0; i < n; ++i)
 582                         tcp->u_arg[i] = args[i];
 583         }
 584 }
 585 #endif
 586
 587 #ifdef SYS_ipc_subcall
 588 static void
 589 decode_ipc_subcall(struct tcb *tcp)
 590 {
 591         unsigned int i, n;
 592
 593         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_ipc_nsubcalls)
 594                 return;
 595
 596         tcp->scno = SYS_ipc_subcall + tcp->u_arg[0];
 597         tcp->qual_flg = qual_flags[tcp->scno];
 598         tcp->s_ent = &sysent[tcp->scno];
 599         n = tcp->s_ent->nargs;
 600         for (i = 0; i < n; i++)
 601                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 602 }
 603 #endif
 604
 605 #ifdef LINUX_MIPSO32
 606 static void
 607 decode_mips_subcall(struct tcb *tcp)
 608 {
 609         if (!SCNO_IS_VALID(tcp->u_arg[0]))
 610                 return;
 611         tcp->scno = tcp->u_arg[0];
 612         tcp->qual_flg = qual_flags[tcp->scno];
 613         tcp->s_ent = &sysent[tcp->scno];
 614         memmove(&tcp->u_arg[0], &tcp->u_arg[1],
 615                 sizeof(tcp->u_arg) - sizeof(tcp->u_arg[0]));
 616         /*
 617          * Fetching the last arg of 7-arg syscalls (fadvise64_64
 618          * and sync_file_range) would require additional code,
 619          * see linux/mips/get_syscall_args.c
 620          */
 621 }
 622
 623 SYS_FUNC(syscall)
 624 {
 625         return printargs(tcp);
 626 }
 627 #endif
 628
 629 int
 630 printargs(struct tcb *tcp)
 631 {
 632         if (entering(tcp)) {
 633                 int i;
 634                 int n = tcp->s_ent->nargs;
 635                 for (i = 0; i < n; i++)
 636                         tprintf("%s%#lx", i ? ", " : "", tcp->u_arg[i]);
 637         }
 638         return 0;
 639 }
 640
 641 int
 642 printargs_lu(struct tcb *tcp)
 643 {
 644         if (entering(tcp)) {
 645                 int i;
 646                 int n = tcp->s_ent->nargs;
 647                 for (i = 0; i < n; i++)
 648                         tprintf("%s%lu", i ? ", " : "", tcp->u_arg[i]);
 649         }
 650         return 0;
 651 }
 652
 653 int
 654 printargs_ld(struct tcb *tcp)
 655 {
 656         if (entering(tcp)) {
 657                 int i;
 658                 int n = tcp->s_ent->nargs;
 659                 for (i = 0; i < n; i++)
 660                         tprintf("%s%ld", i ? ", " : "", tcp->u_arg[i]);
 661         }
 662         return 0;
 663 }
 664
 665 static void
 666 dumpio(struct tcb *tcp)
 667 {
 668         int (*func)();
 669
 670         if (syserror(tcp))
 671                 return;
 672         if ((unsigned long) tcp->u_arg[0] >= num_quals)
 673                 return;
 674         func = tcp->s_ent->sys_func;
 675         if (func == printargs)
 676                 return;
 677         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
 678                 if (func == sys_read ||
 679                     func == sys_pread ||
 680                     func == sys_recv ||
 681                     func == sys_recvfrom) {
 682                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
 683                         return;
 684                 } else if (func == sys_readv) {
 685                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
 686                         return;
 687 #if HAVE_SENDMSG
 688                 } else if (func == sys_recvmsg) {
 689                         dumpiov_in_msghdr(tcp, tcp->u_arg[1]);
 690                         return;
 691                 } else if (func == sys_recvmmsg) {
 692                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 693                         return;
 694 #endif
 695                 }
 696         }
 697         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
 698                 if (func == sys_write ||
 699                     func == sys_pwrite ||
 700                     func == sys_send ||
 701                     func == sys_sendto)
 702                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 703                 else if (func == sys_writev)
 704                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
 705 #if HAVE_SENDMSG
 706                 else if (func == sys_sendmsg)
 707                         dumpiov_in_msghdr(tcp, tcp->u_arg[1]);
 708                 else if (func == sys_sendmmsg)
 709                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 710 #endif
 711         }
 712 }
 713
 714 /*
 715  * Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 716  * The shuffling should be an involution: shuffle_scno(shuffle_scno(n)) == n.
 717  */
 718 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
 719 static long
 720 shuffle_scno(unsigned long scno)
 721 {
 722         if (scno < ARM_FIRST_SHUFFLED_SYSCALL)
 723                 return scno;
 724
 725         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 726         if (scno == ARM_FIRST_SHUFFLED_SYSCALL)
 727                 return 0x000ffff0;
 728         if (scno == 0x000ffff0)
 729                 return ARM_FIRST_SHUFFLED_SYSCALL;
 730
 731 #define ARM_SECOND_SHUFFLED_SYSCALL (ARM_FIRST_SHUFFLED_SYSCALL + 1)
 732         /*
 733          * Is it ARM specific syscall?
 734          * Swap [0x000f0000, 0x000f0000 + LAST_SPECIAL] range
 735          * with [SECOND_SHUFFLED, SECOND_SHUFFLED + LAST_SPECIAL] range.
 736          */
 737         if (scno >= 0x000f0000 &&
 738             scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL) {
 739                 return scno - 0x000f0000 + ARM_SECOND_SHUFFLED_SYSCALL;
 740         }
 741         if (scno <= ARM_SECOND_SHUFFLED_SYSCALL + ARM_LAST_SPECIAL_SYSCALL) {
 742                 return scno + 0x000f0000 - ARM_SECOND_SHUFFLED_SYSCALL;
 743         }
 744
 745         return scno;
 746 }
 747 #else
 748 # define shuffle_scno(scno) ((long)(scno))
 749 #endif
 750
 751 static char*
 752 undefined_scno_name(struct tcb *tcp)
 753 {
 754         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
 755
 756         sprintf(buf, "syscall_%lu", shuffle_scno(tcp->scno));
 757         return buf;
 758 }
 759
 760 static long get_regs_error;
 761
 762 void
 763 clear_regs(void)
 764 {
 765         get_regs_error = -1;
 766 }
 767
 768 static int get_syscall_args(struct tcb *);
 769 static int get_syscall_result(struct tcb *);
 770
 771 static int
 772 trace_syscall_entering(struct tcb *tcp)
 773 {
 774         int res, scno_good;
 775
 776         scno_good = res = get_scno(tcp);
 777         if (res == 0)
 778                 return res;
 779         if (res == 1)
 780                 res = get_syscall_args(tcp);
 781
 782         if (res != 1) {
 783                 printleader(tcp);
 784                 if (scno_good != 1)
 785                         tprints("????" /* anti-trigraph gap */ "(");
 786                 else if (tcp->qual_flg & UNDEFINED_SCNO)
 787                         tprintf("%s(", undefined_scno_name(tcp));
 788                 else
 789                         tprintf("%s(", tcp->s_ent->sys_name);
 790                 /*
 791                  * " <unavailable>" will be added later by the code which
 792                  * detects ptrace errors.
 793                  */
 794                 goto ret;
 795         }
 796
 797 #ifdef LINUX_MIPSO32
 798         if (sys_syscall == tcp->s_ent->sys_func)
 799                 decode_mips_subcall(tcp);
 800 #endif
 801
 802         if (   sys_execve == tcp->s_ent->sys_func
 803 # if defined(SPARC) || defined(SPARC64)
 804             || sys_execv == tcp->s_ent->sys_func
 805 # endif
 806            ) {
 807                 hide_log_until_execve = 0;
 808         }
 809
 810 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
 811         while (1) {
 812 # ifdef SYS_socket_subcall
 813                 if (tcp->s_ent->sys_func == sys_socketcall) {
 814                         decode_socket_subcall(tcp);
 815                         break;
 816                 }
 817 # endif
 818 # ifdef SYS_ipc_subcall
 819                 if (tcp->s_ent->sys_func == sys_ipc) {
 820                         decode_ipc_subcall(tcp);
 821                         break;
 822                 }
 823 # endif
 824                 break;
 825         }
 826 #endif
 827
 828         if (!(tcp->qual_flg & QUAL_TRACE)
 829          || (tracing_paths && !pathtrace_match(tcp))
 830         ) {
 831                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
 832                 return 0;
 833         }
 834
 835         tcp->flags &= ~TCB_FILTERED;
 836
 837         if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
 838                 res = 0;
 839                 goto ret;
 840         }
 841
 842 #ifdef USE_LIBUNWIND
 843         if (stack_trace_enabled) {
 844                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
 845                         unwind_capture_stacktrace(tcp);
 846         }
 847 #endif
 848
 849         printleader(tcp);
 850         if (tcp->qual_flg & UNDEFINED_SCNO)
 851                 tprintf("%s(", undefined_scno_name(tcp));
 852         else
 853                 tprintf("%s(", tcp->s_ent->sys_name);
 854         if ((tcp->qual_flg & QUAL_RAW) && tcp->s_ent->sys_func != sys_exit)
 855                 res = printargs(tcp);
 856         else
 857                 res = tcp->s_ent->sys_func(tcp);
 858
 859         fflush(tcp->outf);
 860  ret:
 861         tcp->flags |= TCB_INSYSCALL;
 862         /* Measure the entrance time as late as possible to avoid errors. */
 863         if (Tflag || cflag)
 864                 gettimeofday(&tcp->etime, NULL);
 865         return res;
 866 }
 867
 868 static int
 869 trace_syscall_exiting(struct tcb *tcp)
 870 {
 871         int sys_res;
 872         struct timeval tv;
 873         int res;
 874         long u_error;
 875
 876         /* Measure the exit time as early as possible to avoid errors. */
 877         if (Tflag || cflag)
 878                 gettimeofday(&tv, NULL);
 879
 880 #ifdef USE_LIBUNWIND
 881         if (stack_trace_enabled) {
 882                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
 883                         unwind_cache_invalidate(tcp);
 884         }
 885 #endif
 886
 887 #if SUPPORTED_PERSONALITIES > 1
 888         update_personality(tcp, tcp->currpers);
 889 #endif
 890         res = (get_regs_error ? -1 : get_syscall_result(tcp));
 891         if (res == 1) {
 892                 if (filtered(tcp) || hide_log_until_execve)
 893                         goto ret;
 894         }
 895
 896         if (cflag) {
 897                 count_syscall(tcp, &tv);
 898                 if (cflag == CFLAG_ONLY_STATS) {
 899                         goto ret;
 900                 }
 901         }
 902
 903         /* If not in -ff mode, and printing_tcp != tcp,
 904          * then the log currently does not end with output
 905          * of _our syscall entry_, but with something else.
 906          * We need to say which syscall's return is this.
 907          *
 908          * Forced reprinting via TCB_REPRINT is used only by
 909          * "strace -ff -oLOG test/threaded_execve" corner case.
 910          * It's the only case when -ff mode needs reprinting.
 911          */
 912         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
 913                 tcp->flags &= ~TCB_REPRINT;
 914                 printleader(tcp);
 915                 if (tcp->qual_flg & UNDEFINED_SCNO)
 916                         tprintf("<... %s resumed> ", undefined_scno_name(tcp));
 917                 else
 918                         tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
 919         }
 920         printing_tcp = tcp;
 921
 922         tcp->s_prev_ent = NULL;
 923         if (res != 1) {
 924                 /* There was error in one of prior ptrace ops */
 925                 tprints(") ");
 926                 tabto();
 927                 tprints("= ? <unavailable>\n");
 928                 line_ended();
 929                 tcp->flags &= ~TCB_INSYSCALL;
 930                 return res;
 931         }
 932         tcp->s_prev_ent = tcp->s_ent;
 933
 934         sys_res = 0;
 935         if (tcp->qual_flg & QUAL_RAW) {
 936                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
 937         } else {
 938         /* FIXME: not_failing_only (IOW, option -z) is broken:
 939          * failure of syscall is known only after syscall return.
 940          * Thus we end up with something like this on, say, ENOENT:
 941          *     open("doesnt_exist", O_RDONLY <unfinished ...>
 942          *     {next syscall decode}
 943          * whereas the intended result is that open(...) line
 944          * is not shown at all.
 945          */
 946                 if (not_failing_only && tcp->u_error)
 947                         goto ret;       /* ignore failed syscalls */
 948                 sys_res = tcp->s_ent->sys_func(tcp);
 949         }
 950
 951         tprints(") ");
 952         tabto();
 953         u_error = tcp->u_error;
 954         if (tcp->qual_flg & QUAL_RAW) {
 955                 if (u_error)
 956                         tprintf("= -1 (errno %ld)", u_error);
 957                 else
 958                         tprintf("= %#lx", tcp->u_rval);
 959         }
 960         else if (!(sys_res & RVAL_NONE) && u_error) {
 961                 switch (u_error) {
 962                 /* Blocked signals do not interrupt any syscalls.
 963                  * In this case syscalls don't return ERESTARTfoo codes.
 964                  *
 965                  * Deadly signals set to SIG_DFL interrupt syscalls
 966                  * and kill the process regardless of which of the codes below
 967                  * is returned by the interrupted syscall.
 968                  * In some cases, kernel forces a kernel-generated deadly
 969                  * signal to be unblocked and set to SIG_DFL (and thus cause
 970                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
 971                  * or SIGILL. (The alternative is to leave process spinning
 972                  * forever on the faulty instruction - not useful).
 973                  *
 974                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
 975                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
 976                  * but kernel will always restart them.
 977                  */
 978                 case ERESTARTSYS:
 979                         /* Most common type of signal-interrupted syscall exit code.
 980                          * The system call will be restarted with the same arguments
 981                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
 982                          */
 983                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
 984                         break;
 985                 case ERESTARTNOINTR:
 986                         /* Rare. For example, fork() returns this if interrupted.
 987                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
 988                          */
 989                         tprints("= ? ERESTARTNOINTR (To be restarted)");
 990                         break;
 991                 case ERESTARTNOHAND:
 992                         /* pause(), rt_sigsuspend() etc use this code.
 993                          * SA_RESTART is ignored (assumed not set):
 994                          * syscall won't restart (will return EINTR instead)
 995                          * even after signal with SA_RESTART set. However,
 996                          * after SIG_IGN or SIG_DFL signal it will restart
 997                          * (thus the name "restart only if has no handler").
 998                          */
 999                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
1000                         break;
1001                 case ERESTART_RESTARTBLOCK:
1002                         /* Syscalls like nanosleep(), poll() which can't be
1003                          * restarted with their original arguments use this
1004                          * code. Kernel will execute restart_syscall() instead,
1005                          * which changes arguments before restarting syscall.
1006                          * SA_RESTART is ignored (assumed not set) similarly
1007                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
1008                          * since restart data is saved in "restart block"
1009                          * in task struct, and if signal handler uses a syscall
1010                          * which in turn saves another such restart block,
1011                          * old data is lost and restart becomes impossible)
1012                          */
1013                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
1014                         break;
1015                 default:
1016                         if ((unsigned long) u_error < nerrnos
1017                             && errnoent[u_error])
1018                                 tprintf("= -1 %s (%s)", errnoent[u_error],
1019                                         strerror(u_error));
1020                         else
1021                                 tprintf("= -1 ERRNO_%lu (%s)", u_error,
1022                                         strerror(u_error));
1023                         break;
1024                 }
1025                 if ((sys_res & RVAL_STR) && tcp->auxstr)
1026                         tprintf(" (%s)", tcp->auxstr);
1027         }
1028         else {
1029                 if (sys_res & RVAL_NONE)
1030                         tprints("= ?");
1031                 else {
1032                         switch (sys_res & RVAL_MASK) {
1033                         case RVAL_HEX:
1034 #if SUPPORTED_PERSONALITIES > 1
1035                                 if (current_wordsize < sizeof(long))
1036                                         tprintf("= %#x",
1037                                                 (unsigned int) tcp->u_rval);
1038                                 else
1039 #endif
1040                                         tprintf("= %#lx", tcp->u_rval);
1041                                 break;
1042                         case RVAL_OCTAL:
1043                                 tprintf("= %#lo", tcp->u_rval);
1044                                 break;
1045                         case RVAL_UDECIMAL:
1046                                 tprintf("= %lu", tcp->u_rval);
1047                                 break;
1048                         case RVAL_DECIMAL:
1049                                 tprintf("= %ld", tcp->u_rval);
1050                                 break;
1051                         case RVAL_FD:
1052                                 if (show_fd_path) {
1053                                         tprints("= ");
1054                                         printfd(tcp, tcp->u_rval);
1055                                 }
1056                                 else
1057                                         tprintf("= %ld", tcp->u_rval);
1058                                 break;
1059 #if defined(LINUX_MIPSN32) || defined(X32)
1060                         /*
1061                         case RVAL_LHEX:
1062                                 tprintf("= %#llx", tcp->u_lrval);
1063                                 break;
1064                         case RVAL_LOCTAL:
1065                                 tprintf("= %#llo", tcp->u_lrval);
1066                                 break;
1067                         */
1068                         case RVAL_LUDECIMAL:
1069                                 tprintf("= %llu", tcp->u_lrval);
1070                                 break;
1071                         /*
1072                         case RVAL_LDECIMAL:
1073                                 tprintf("= %lld", tcp->u_lrval);
1074                                 break;
1075                         */
1076 #endif
1077                         default:
1078                                 fprintf(stderr,
1079                                         "invalid rval format\n");
1080                                 break;
1081                         }
1082                 }
1083                 if ((sys_res & RVAL_STR) && tcp->auxstr)
1084                         tprintf(" (%s)", tcp->auxstr);
1085         }
1086         if (Tflag) {
1087                 tv_sub(&tv, &tv, &tcp->etime);
1088                 tprintf(" <%ld.%06ld>",
1089                         (long) tv.tv_sec, (long) tv.tv_usec);
1090         }
1091         tprints("\n");
1092         dumpio(tcp);
1093         line_ended();
1094
1095 #ifdef USE_LIBUNWIND
1096         if (stack_trace_enabled)
1097                 unwind_print_stacktrace(tcp);
1098 #endif
1099
1100  ret:
1101         tcp->flags &= ~TCB_INSYSCALL;
1102         return 0;
1103 }
1104
1105 int
1106 trace_syscall(struct tcb *tcp)
1107 {
1108         return exiting(tcp) ?
1109                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
1110 }
1111
1112 /*
1113  * Cannot rely on __kernel_[u]long_t being defined,
1114  * it is quite a recent feature of <asm/posix_types.h>.
1115  */
1116 #ifdef __kernel_long_t
1117 typedef __kernel_long_t kernel_long_t;
1118 typedef __kernel_ulong_t kernel_ulong_t;
1119 #else
1120 # ifdef X32
1121 typedef long long kernel_long_t;
1122 typedef unsigned long long kernel_ulong_t;
1123 # else
1124 typedef long kernel_long_t;
1125 typedef unsigned long kernel_ulong_t;
1126 # endif
1127 #endif
1128
1129 /*
1130  * Check the syscall return value register value for whether it is
1131  * a negated errno code indicating an error, or a success return value.
1132  */
1133 static inline bool
1134 is_negated_errno(kernel_ulong_t val)
1135 {
1136         /* Linux kernel defines MAX_ERRNO to 4095. */
1137         kernel_ulong_t max = -(kernel_long_t) 4095;
1138
1139 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
1140         if (current_wordsize < sizeof(val)) {
1141                 val = (uint32_t) val;
1142                 max = (uint32_t) max;
1143         }
1144 #elif defined X32
1145         /*
1146          * current_wordsize is 4 even in personality 0 (native X32)
1147          * but truncation _must not_ be done in it.
1148          * can't check current_wordsize here!
1149          */
1150         if (current_personality != 0) {
1151                 val = (uint32_t) val;
1152                 max = (uint32_t) max;
1153         }
1154 #endif
1155
1156         return val >= max;
1157 }
1158
1159 #include "arch_regs.c"
1160
1161 #ifdef HAVE_GETRVAL2
1162 # include "arch_getrval2.c"
1163 #endif
1164
1165 void
1166 print_pc(struct tcb *tcp)
1167 {
1168         const char *fmt;
1169         const char *bad;
1170
1171 #ifdef current_wordsize
1172 # define pc_wordsize current_wordsize
1173 #else
1174 # define pc_wordsize personality_wordsize[tcp->currpers]
1175 #endif
1176
1177         if (pc_wordsize == 4) {
1178                 fmt = "[%08lx] ";
1179                 bad = "[????????] ";
1180         } else {
1181                 fmt = "[%016lx] ";
1182                 bad = "[????????????????] ";
1183         }
1184
1185 #undef pc_wordsize
1186 #define PRINTBADPC tprints(bad)
1187
1188         if (get_regs_error) {
1189                 PRINTBADPC;
1190                 return;
1191         }
1192
1193 #include "print_pc.c"
1194 }
1195
1196 #if defined X86_64 || defined POWERPC
1197 # include "getregs_old.c"
1198 #endif
1199
1200 #if defined ARCH_REGS_FOR_GETREGSET
1201 static long
1202 get_regset(pid_t pid)
1203 {
1204 # ifdef ARCH_IOVEC_FOR_GETREGSET
1205         /* variable iovec */
1206         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1207         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1208                       &ARCH_IOVEC_FOR_GETREGSET);
1209 # else
1210         /* constant iovec */
1211         static struct iovec io = {
1212                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1213                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1214         };
1215         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1216
1217 # endif
1218 }
1219 #endif /* ARCH_REGS_FOR_GETREGSET */
1220
1221 void
1222 get_regs(pid_t pid)
1223 {
1224 #ifdef ARCH_REGS_FOR_GETREGSET
1225 # ifdef X86_64
1226         /* Try PTRACE_GETREGSET first, fallback to PTRACE_GETREGS. */
1227         static int getregset_support;
1228
1229         if (getregset_support >= 0) {
1230                 get_regs_error = get_regset(pid);
1231                 if (getregset_support > 0)
1232                         return;
1233                 if (get_regs_error >= 0) {
1234                         getregset_support = 1;
1235                         return;
1236                 }
1237                 if (errno == EPERM || errno == ESRCH)
1238                         return;
1239                 getregset_support = -1;
1240         }
1241         getregs_old(pid);
1242 # else /* !X86_64 */
1243         /* Assume that PTRACE_GETREGSET works. */
1244         get_regs_error = get_regset(pid);
1245 # endif
1246 #elif defined ARCH_REGS_FOR_GETREGS
1247 # if defined SPARC || defined SPARC64
1248         /* SPARC systems have the meaning of data and addr reversed */
1249         get_regs_error = ptrace(PTRACE_GETREGS, pid, (char *)&ARCH_REGS_FOR_GETREGS, 0);
1250 # elif defined POWERPC
1251         static bool old_kernel = 0;
1252         if (old_kernel)
1253                 goto old;
1254         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1255         if (get_regs_error && errno == EIO) {
1256                 old_kernel = 1;
1257  old:
1258                 get_regs_error = getregs_old(pid);
1259         }
1260 # else
1261         /* Assume that PTRACE_GETREGS works. */
1262         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1263 # endif
1264
1265 #else /* !ARCH_REGS_FOR_GETREGSET && !ARCH_REGS_FOR_GETREGS */
1266 #  warning get_regs is not implemented for this architecture yet
1267         get_regs_error = 0;
1268 #endif
1269 }
1270
1271 /* Returns:
1272  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1273  * 1: ok, continue in trace_syscall_entering().
1274  * other: error, trace_syscall_entering() should print error indicator
1275  *    ("????" etc) and bail out.
1276  */
1277 int
1278 get_scno(struct tcb *tcp)
1279 {
1280         if (get_regs_error)
1281                 return -1;
1282
1283         long scno = 0;
1284
1285 #include "get_scno.c"
1286
1287         tcp->scno = scno;
1288         if (SCNO_IS_VALID(tcp->scno)) {
1289                 tcp->s_ent = &sysent[scno];
1290                 tcp->qual_flg = qual_flags[scno];
1291         } else {
1292                 static const struct_sysent unknown = {
1293                         .nargs = MAX_ARGS,
1294                         .sys_flags = 0,
1295                         .sys_func = printargs,
1296                         .sys_name = "system call",
1297                 };
1298                 tcp->s_ent = &unknown;
1299                 tcp->qual_flg = UNDEFINED_SCNO | QUAL_RAW | DEFAULT_QUAL_FLAGS;
1300                 if (debug_flag)
1301                         fprintf(stderr, "pid %d invalid syscall %ld\n",
1302                                 tcp->pid, scno);
1303         }
1304         return 1;
1305 }
1306
1307 /* Return -1 on error or 1 on success (never 0!) */
1308 static int
1309 get_syscall_args(struct tcb *tcp)
1310 {
1311 #include "get_syscall_args.c"
1312         return 1;
1313 }
1314
1315 static void
1316 get_error(struct tcb *tcp)
1317 {
1318         const bool check_errno = !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS);
1319         tcp->u_error = 0;
1320
1321 #include "get_error.c"
1322 }
1323
1324 /* Returns:
1325  * 1: ok, continue in trace_syscall_exiting().
1326  * -1: error, trace_syscall_exiting() should print error indicator
1327  *    ("????" etc) and bail out.
1328  */
1329 static int
1330 get_syscall_result(struct tcb *tcp)
1331 {
1332 #if defined ARCH_REGS_FOR_GETREGSET || defined ARCH_REGS_FOR_GETREGS
1333         /* already done by get_regs */
1334 #else
1335 # include "get_syscall_result.c"
1336 #endif
1337         get_error(tcp);
1338         return 1;
1339 }