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 "native_defs.h"
  36 #include <sys/param.h>
  37 #include <signal.h>
  38
  39 /* for struct iovec */
  40 #include <sys/uio.h>
  41
  42 #include "regs.h"
  43 #include "ptrace.h"
  44
  45 #if defined(SPARC64)
  46 # undef PTRACE_GETREGS
  47 # define PTRACE_GETREGS PTRACE_GETREGS64
  48 # undef PTRACE_SETREGS
  49 # define PTRACE_SETREGS PTRACE_SETREGS64
  50 #endif
  51
  52 #if defined SPARC64
  53 # include <asm/psrcompat.h>
  54 #elif defined SPARC
  55 # include <asm/psr.h>
  56 #endif
  57
  58 #ifdef IA64
  59 # include <asm/rse.h>
  60 #endif
  61
  62 #ifndef NT_PRSTATUS
  63 # define NT_PRSTATUS 1
  64 #endif
  65
  66 #ifndef NSIG
  67 # warning: NSIG is not defined, using 32
  68 # define NSIG 32
  69 #endif
  70
  71 #include "syscall.h"
  72
  73 /* Define these shorthand notations to simplify the syscallent files. */
  74 #define TD TRACE_DESC
  75 #define TF TRACE_FILE
  76 #define TI TRACE_IPC
  77 #define TN TRACE_NETWORK
  78 #define TP TRACE_PROCESS
  79 #define TS TRACE_SIGNAL
  80 #define TM TRACE_MEMORY
  81 #define NF SYSCALL_NEVER_FAILS
  82 #define MA MAX_ARGS
  83 #define SI STACKTRACE_INVALIDATE_CACHE
  84 #define SE STACKTRACE_CAPTURE_ON_ENTER
  85
  86 #define SEN(syscall_name) SEN_ ## syscall_name, SYS_FUNC_NAME(sys_ ## syscall_name)
  87
  88 const struct_sysent sysent0[] = {
  89 #include "syscallent.h"
  90 };
  91
  92 #if SUPPORTED_PERSONALITIES > 1
  93 # include PERSONALITY1_INCLUDE_FUNCS
  94 static const struct_sysent sysent1[] = {
  95 # include "syscallent1.h"
  96 };
  97 #endif
  98
  99 #if SUPPORTED_PERSONALITIES > 2
 100 # include PERSONALITY2_INCLUDE_FUNCS
 101 static const struct_sysent sysent2[] = {
 102 # include "syscallent2.h"
 103 };
 104 #endif
 105
 106 /* Now undef them since short defines cause wicked namespace pollution. */
 107 #undef SEN
 108 #undef TD
 109 #undef TF
 110 #undef TI
 111 #undef TN
 112 #undef TP
 113 #undef TS
 114 #undef TM
 115 #undef NF
 116 #undef MA
 117 #undef SI
 118 #undef SE
 119
 120 /*
 121  * `ioctlent[012].h' files are automatically generated by the auxiliary
 122  * program `ioctlsort', such that the list is sorted by the `code' field.
 123  * This has the side-effect of resolving the _IO.. macros into
 124  * plain integers, eliminating the need to include here everything
 125  * in "/usr/include".
 126  */
 127
 128 const char *const errnoent0[] = {
 129 #include "errnoent.h"
 130 };
 131 const char *const signalent0[] = {
 132 #include "signalent.h"
 133 };
 134 const struct_ioctlent ioctlent0[] = {
 135 #include "ioctlent0.h"
 136 };
 137
 138 #if SUPPORTED_PERSONALITIES > 1
 139 static const char *const errnoent1[] = {
 140 # include "errnoent1.h"
 141 };
 142 static const char *const signalent1[] = {
 143 # include "signalent1.h"
 144 };
 145 static const struct_ioctlent ioctlent1[] = {
 146 # include "ioctlent1.h"
 147 };
 148 # include PERSONALITY0_INCLUDE_PRINTERS_DECLS
 149 static const struct_printers printers0 = {
 150 # include PERSONALITY0_INCLUDE_PRINTERS_DEFS
 151 };
 152 # include PERSONALITY1_INCLUDE_PRINTERS_DECLS
 153 static const struct_printers printers1 = {
 154 # include PERSONALITY1_INCLUDE_PRINTERS_DEFS
 155 };
 156 #endif
 157
 158 #if SUPPORTED_PERSONALITIES > 2
 159 static const char *const errnoent2[] = {
 160 # include "errnoent2.h"
 161 };
 162 static const char *const signalent2[] = {
 163 # include "signalent2.h"
 164 };
 165 static const struct_ioctlent ioctlent2[] = {
 166 # include "ioctlent2.h"
 167 };
 168 # include PERSONALITY2_INCLUDE_PRINTERS_DECLS
 169 static const struct_printers printers2 = {
 170 # include PERSONALITY2_INCLUDE_PRINTERS_DEFS
 171 };
 172 #endif
 173
 174 enum {
 175         nsyscalls0 = ARRAY_SIZE(sysent0)
 176 #if SUPPORTED_PERSONALITIES > 1
 177         , nsyscalls1 = ARRAY_SIZE(sysent1)
 178 # if SUPPORTED_PERSONALITIES > 2
 179         , nsyscalls2 = ARRAY_SIZE(sysent2)
 180 # endif
 181 #endif
 182 };
 183
 184 enum {
 185         nerrnos0 = ARRAY_SIZE(errnoent0)
 186 #if SUPPORTED_PERSONALITIES > 1
 187         , nerrnos1 = ARRAY_SIZE(errnoent1)
 188 # if SUPPORTED_PERSONALITIES > 2
 189         , nerrnos2 = ARRAY_SIZE(errnoent2)
 190 # endif
 191 #endif
 192 };
 193
 194 enum {
 195         nsignals0 = ARRAY_SIZE(signalent0)
 196 #if SUPPORTED_PERSONALITIES > 1
 197         , nsignals1 = ARRAY_SIZE(signalent1)
 198 # if SUPPORTED_PERSONALITIES > 2
 199         , nsignals2 = ARRAY_SIZE(signalent2)
 200 # endif
 201 #endif
 202 };
 203
 204 enum {
 205         nioctlents0 = ARRAY_SIZE(ioctlent0)
 206 #if SUPPORTED_PERSONALITIES > 1
 207         , nioctlents1 = ARRAY_SIZE(ioctlent1)
 208 # if SUPPORTED_PERSONALITIES > 2
 209         , nioctlents2 = ARRAY_SIZE(ioctlent2)
 210 # endif
 211 #endif
 212 };
 213
 214 #if SUPPORTED_PERSONALITIES > 1
 215 const struct_sysent *sysent = sysent0;
 216 const char *const *errnoent = errnoent0;
 217 const char *const *signalent = signalent0;
 218 const struct_ioctlent *ioctlent = ioctlent0;
 219 const struct_printers *printers = &printers0;
 220 #endif
 221
 222 unsigned nsyscalls = nsyscalls0;
 223 unsigned nerrnos = nerrnos0;
 224 unsigned nsignals = nsignals0;
 225 unsigned nioctlents = nioctlents0;
 226
 227 unsigned num_quals;
 228 qualbits_t *qual_vec[SUPPORTED_PERSONALITIES];
 229
 230 static const unsigned nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 231         nsyscalls0,
 232 #if SUPPORTED_PERSONALITIES > 1
 233         nsyscalls1,
 234 #endif
 235 #if SUPPORTED_PERSONALITIES > 2
 236         nsyscalls2,
 237 #endif
 238 };
 239 static const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 240         sysent0,
 241 #if SUPPORTED_PERSONALITIES > 1
 242         sysent1,
 243 #endif
 244 #if SUPPORTED_PERSONALITIES > 2
 245         sysent2,
 246 #endif
 247 };
 248
 249 enum {
 250         MAX_NSYSCALLS1 = (nsyscalls0
 251 #if SUPPORTED_PERSONALITIES > 1
 252                         > nsyscalls1 ? nsyscalls0 : nsyscalls1
 253 #endif
 254                         ),
 255         MAX_NSYSCALLS2 = (MAX_NSYSCALLS1
 256 #if SUPPORTED_PERSONALITIES > 2
 257                         > nsyscalls2 ? MAX_NSYSCALLS1 : nsyscalls2
 258 #endif
 259                         ),
 260         MAX_NSYSCALLS = MAX_NSYSCALLS2,
 261         /* We are ready for arches with up to 255 signals,
 262          * even though the largest known signo is on MIPS and it is 128.
 263          * The number of existing syscalls on all arches is
 264          * larger that 255 anyway, so it is just a pedantic matter.
 265          */
 266         MIN_QUALS = MAX_NSYSCALLS > 255 ? MAX_NSYSCALLS : 255
 267 };
 268
 269 #if SUPPORTED_PERSONALITIES > 1
 270 unsigned current_personality;
 271
 272 # ifndef current_wordsize
 273 unsigned current_wordsize;
 274 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 275         PERSONALITY0_WORDSIZE,
 276         PERSONALITY1_WORDSIZE,
 277 # if SUPPORTED_PERSONALITIES > 2
 278         PERSONALITY2_WORDSIZE,
 279 # endif
 280 };
 281 # endif
 282
 283 void
 284 set_personality(int personality)
 285 {
 286         nsyscalls = nsyscall_vec[personality];
 287         sysent = sysent_vec[personality];
 288
 289         switch (personality) {
 290         case 0:
 291                 errnoent = errnoent0;
 292                 nerrnos = nerrnos0;
 293                 ioctlent = ioctlent0;
 294                 nioctlents = nioctlents0;
 295                 signalent = signalent0;
 296                 nsignals = nsignals0;
 297                 printers = &printers0;
 298                 break;
 299
 300         case 1:
 301                 errnoent = errnoent1;
 302                 nerrnos = nerrnos1;
 303                 ioctlent = ioctlent1;
 304                 nioctlents = nioctlents1;
 305                 signalent = signalent1;
 306                 nsignals = nsignals1;
 307                 printers = &printers1;
 308                 break;
 309
 310 # if SUPPORTED_PERSONALITIES > 2
 311         case 2:
 312                 errnoent = errnoent2;
 313                 nerrnos = nerrnos2;
 314                 ioctlent = ioctlent2;
 315                 nioctlents = nioctlents2;
 316                 signalent = signalent2;
 317                 nsignals = nsignals2;
 318                 printers = &printers2;
 319                 break;
 320 # endif
 321         }
 322
 323         current_personality = personality;
 324 # ifndef current_wordsize
 325         current_wordsize = personality_wordsize[personality];
 326 # endif
 327 }
 328
 329 static void
 330 update_personality(struct tcb *tcp, unsigned int personality)
 331 {
 332         if (personality == current_personality)
 333                 return;
 334         set_personality(personality);
 335
 336         if (personality == tcp->currpers)
 337                 return;
 338         tcp->currpers = personality;
 339
 340 # undef PERSONALITY_NAMES
 341 # if defined POWERPC64
 342 #  define PERSONALITY_NAMES {"64 bit", "32 bit"}
 343 # elif defined X86_64
 344 #  define PERSONALITY_NAMES {"64 bit", "32 bit", "x32"}
 345 # elif defined X32
 346 #  define PERSONALITY_NAMES {"x32", "32 bit"}
 347 # elif defined AARCH64
 348 #  define PERSONALITY_NAMES {"64 bit", "32 bit"}
 349 # elif defined TILE
 350 #  define PERSONALITY_NAMES {"64-bit", "32-bit"}
 351 # endif
 352 # ifdef PERSONALITY_NAMES
 353         if (!qflag) {
 354                 static const char *const names[] = PERSONALITY_NAMES;
 355                 error_msg("[ Process PID=%d runs in %s mode. ]",
 356                           tcp->pid, names[personality]);
 357         }
 358 # endif
 359 }
 360 #endif
 361
 362 static int qual_desc(const char *, unsigned int, int);
 363 static int qual_signal(const char *, unsigned int, int);
 364 static int qual_syscall(const char *, unsigned int, int);
 365
 366 static const struct qual_options {
 367         unsigned int bitflag;
 368         const char *option_name;
 369         int (*qualify)(const char *, unsigned int, int);
 370         const char *argument_name;
 371 } qual_options[] = {
 372         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
 373         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
 374         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
 375         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
 376         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
 377         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
 378         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
 379         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
 380         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
 381         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
 382         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
 383         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
 384         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
 385         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
 386         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
 387         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
 388         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
 389         { 0,            NULL,           NULL,           NULL            },
 390 };
 391
 392 static void
 393 reallocate_vec(void **vec, unsigned int old_nmemb,
 394                size_t size, unsigned int new_nmemb)
 395 {
 396         unsigned int p;
 397
 398         for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
 399                 vec[p] = xreallocarray(vec[p], new_nmemb, size);
 400                 memset(vec[p] + size * old_nmemb, 0,
 401                        (new_nmemb - old_nmemb) * size);
 402         }
 403 }
 404
 405 static void
 406 reallocate_qual(const unsigned int n)
 407 {
 408         reallocate_vec((void **) qual_vec, num_quals, sizeof(qualbits_t), n);
 409         num_quals = n;
 410 }
 411
 412 static void
 413 qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
 414 {
 415         int p;
 416
 417         if (num_quals <= n)
 418                 reallocate_qual(n + 1);
 419
 420         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 421                 if (pers == p || pers < 0) {
 422                         if (not)
 423                                 qual_vec[p][n] &= ~bitflag;
 424                         else
 425                                 qual_vec[p][n] |= bitflag;
 426                 }
 427         }
 428 }
 429
 430 static bool
 431 qualify_scno(const char *const s, const unsigned int bitflag,
 432              const int not)
 433 {
 434         unsigned int i;
 435
 436         if (*s < '0' || *s > '9' || (i = string_to_uint(s)) >= MAX_NSYSCALLS)
 437                 return false;
 438
 439         qualify_one(i, bitflag, not, -1);
 440         return true;
 441 }
 442
 443 static int
 444 lookup_class(const char *s)
 445 {
 446         if (strcmp(s, "file") == 0)
 447                 return TRACE_FILE;
 448         if (strcmp(s, "ipc") == 0)
 449                 return TRACE_IPC;
 450         if (strcmp(s, "network") == 0)
 451                 return TRACE_NETWORK;
 452         if (strcmp(s, "process") == 0)
 453                 return TRACE_PROCESS;
 454         if (strcmp(s, "signal") == 0)
 455                 return TRACE_SIGNAL;
 456         if (strcmp(s, "desc") == 0)
 457                 return TRACE_DESC;
 458         if (strcmp(s, "memory") == 0)
 459                 return TRACE_MEMORY;
 460         return -1;
 461 }
 462
 463 static bool
 464 qualify_syscall_class(const char *const s, const unsigned int bitflag,
 465                       const int not)
 466 {
 467         unsigned int p;
 468         const int n = lookup_class(s);
 469
 470         if (n < 0)
 471                 return false;
 472
 473         for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
 474                 unsigned int i;
 475
 476                 for (i = 0; i < nsyscall_vec[p]; ++i) {
 477                         if (sysent_vec[p][i].sys_name
 478                             && (sysent_vec[p][i].sys_flags & n) == n) {
 479                                 qualify_one(i, bitflag, not, p);
 480                         }
 481                 }
 482         }
 483
 484         return true;
 485 }
 486
 487 static bool
 488 qualify_syscall_name(const char *const s, const unsigned int bitflag,
 489                      const int not)
 490 {
 491         bool found = false;
 492         unsigned int p;
 493
 494         for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
 495                 unsigned int i;
 496
 497                 for (i = 0; i < nsyscall_vec[p]; ++i) {
 498                         if (sysent_vec[p][i].sys_name
 499                             && strcmp(s, sysent_vec[p][i].sys_name) == 0) {
 500                                 qualify_one(i, bitflag, not, p);
 501                                 found = true;
 502                         }
 503                 }
 504         }
 505
 506         return found;
 507 }
 508
 509 static int
 510 qual_syscall(const char *s, const unsigned int bitflag, const int not)
 511 {
 512         if (qualify_scno(s, bitflag, not)
 513             || qualify_syscall_class(s, bitflag, not)
 514             || qualify_syscall_name(s, bitflag, not)) {
 515                 return 0;
 516         }
 517
 518         return -1;
 519 }
 520
 521 static int
 522 qual_signal(const char *s, const unsigned int bitflag, const int not)
 523 {
 524         unsigned int i;
 525
 526         if (*s >= '0' && *s <= '9') {
 527                 int signo = string_to_uint(s);
 528                 if (signo < 0 || signo > 255)
 529                         return -1;
 530                 qualify_one(signo, bitflag, not, -1);
 531                 return 0;
 532         }
 533         if (strncasecmp(s, "SIG", 3) == 0)
 534                 s += 3;
 535         for (i = 0; i <= NSIG; i++) {
 536                 if (strcasecmp(s, signame(i) + 3) == 0) {
 537                         qualify_one(i, bitflag, not, -1);
 538                         return 0;
 539                 }
 540         }
 541         return -1;
 542 }
 543
 544 static int
 545 qual_desc(const char *s, const unsigned int bitflag, const int not)
 546 {
 547         if (*s >= '0' && *s <= '9') {
 548                 int desc = string_to_uint(s);
 549                 if (desc < 0 || desc > 0x7fff) /* paranoia */
 550                         return -1;
 551                 qualify_one(desc, bitflag, not, -1);
 552                 return 0;
 553         }
 554         return -1;
 555 }
 556
 557 void
 558 qualify(const char *s)
 559 {
 560         const struct qual_options *opt;
 561         char *copy;
 562         const char *p;
 563         int not;
 564         unsigned int i;
 565
 566         if (num_quals == 0)
 567                 reallocate_qual(MIN_QUALS);
 568
 569         opt = &qual_options[0];
 570         for (i = 0; (p = qual_options[i].option_name); i++) {
 571                 unsigned int len = strlen(p);
 572                 if (strncmp(s, p, len) == 0 && s[len] == '=') {
 573                         opt = &qual_options[i];
 574                         s += len + 1;
 575                         break;
 576                 }
 577         }
 578         not = 0;
 579         if (*s == '!') {
 580                 not = 1;
 581                 s++;
 582         }
 583         if (strcmp(s, "none") == 0) {
 584                 not = 1 - not;
 585                 s = "all";
 586         }
 587         if (strcmp(s, "all") == 0) {
 588                 for (i = 0; i < num_quals; i++) {
 589                         qualify_one(i, opt->bitflag, not, -1);
 590                 }
 591                 return;
 592         }
 593         for (i = 0; i < num_quals; i++) {
 594                 qualify_one(i, opt->bitflag, !not, -1);
 595         }
 596         copy = xstrdup(s);
 597         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
 598                 if (opt->qualify(p, opt->bitflag, not)) {
 599                         error_msg_and_die("invalid %s '%s'",
 600                                 opt->argument_name, p);
 601                 }
 602         }
 603         free(copy);
 604         return;
 605 }
 606
 607 #ifdef SYS_socket_subcall
 608 static void
 609 decode_socket_subcall(struct tcb *tcp)
 610 {
 611         const int call = tcp->u_arg[0];
 612
 613         if (call < 1 || call >= SYS_socket_nsubcalls)
 614                 return;
 615
 616         const unsigned long scno = SYS_socket_subcall + call;
 617         const unsigned int nargs = sysent[scno].nargs;
 618         uint64_t buf[nargs];
 619
 620         if (umoven(tcp, tcp->u_arg[1], nargs * current_wordsize, buf) < 0)
 621                 return;
 622
 623         tcp->scno = scno;
 624         tcp->qual_flg = qual_flags[scno];
 625         tcp->s_ent = &sysent[scno];
 626
 627         unsigned int i;
 628         for (i = 0; i < nargs; ++i)
 629                 tcp->u_arg[i] = (sizeof(uint32_t) == current_wordsize)
 630                                 ? ((uint32_t *) (void *) buf)[i] : buf[i];
 631 }
 632 #endif
 633
 634 #ifdef SYS_ipc_subcall
 635 static void
 636 decode_ipc_subcall(struct tcb *tcp)
 637 {
 638         unsigned int call = tcp->u_arg[0];
 639         const unsigned int version = call >> 16;
 640
 641         if (version) {
 642 # if defined S390 || defined S390X
 643                 return;
 644 # else
 645 #  ifdef SPARC64
 646                 if (current_wordsize == 8)
 647                         return;
 648 #  endif
 649                 set_tcb_priv_ulong(tcp, version);
 650                 call &= 0xffff;
 651 # endif
 652         }
 653
 654         switch (call) {
 655                 case  1: case  2: case  3: case  4:
 656                 case 11: case 12: case 13: case 14:
 657                 case 21: case 22: case 23: case 24:
 658                         break;
 659                 default:
 660                         return;
 661         }
 662
 663         tcp->scno = SYS_ipc_subcall + call;
 664         tcp->qual_flg = qual_flags[tcp->scno];
 665         tcp->s_ent = &sysent[tcp->scno];
 666
 667         const unsigned int n = tcp->s_ent->nargs;
 668         unsigned int i;
 669         for (i = 0; i < n; i++)
 670                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 671 }
 672 #endif
 673
 674 #ifdef LINUX_MIPSO32
 675 static void
 676 decode_mips_subcall(struct tcb *tcp)
 677 {
 678         if (!SCNO_IS_VALID(tcp->u_arg[0]))
 679                 return;
 680         tcp->scno = tcp->u_arg[0];
 681         tcp->qual_flg = qual_flags[tcp->scno];
 682         tcp->s_ent = &sysent[tcp->scno];
 683         memmove(&tcp->u_arg[0], &tcp->u_arg[1],
 684                 sizeof(tcp->u_arg) - sizeof(tcp->u_arg[0]));
 685         /*
 686          * Fetching the last arg of 7-arg syscalls (fadvise64_64
 687          * and sync_file_range) requires additional code,
 688          * see linux/mips/get_syscall_args.c
 689          */
 690         if (tcp->s_ent->nargs == MAX_ARGS) {
 691                 if (umoven(tcp,
 692                            mips_REG_SP + MAX_ARGS * sizeof(tcp->u_arg[0]),
 693                            sizeof(tcp->u_arg[0]),
 694                            &tcp->u_arg[MAX_ARGS - 1]) < 0)
 695                 tcp->u_arg[MAX_ARGS - 1] = 0;
 696         }
 697 }
 698 #endif /* LINUX_MIPSO32 */
 699
 700 static void
 701 dumpio(struct tcb *tcp)
 702 {
 703         int sen;
 704
 705         if (syserror(tcp))
 706                 return;
 707         if ((unsigned long) tcp->u_arg[0] >= num_quals)
 708                 return;
 709         sen = tcp->s_ent->sen;
 710         if (SEN_printargs == sen)
 711                 return;
 712         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
 713                 switch (sen) {
 714                 case SEN_read:
 715                 case SEN_pread:
 716                 case SEN_recv:
 717                 case SEN_recvfrom:
 718                 case SEN_mq_timedreceive:
 719                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
 720                         return;
 721                 case SEN_readv:
 722                 case SEN_preadv:
 723                 case SEN_preadv2:
 724                         dumpiov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1],
 725                                      tcp->u_rval);
 726                         return;
 727                 case SEN_recvmsg:
 728                         dumpiov_in_msghdr(tcp, tcp->u_arg[1], tcp->u_rval);
 729                         return;
 730                 case SEN_recvmmsg:
 731                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 732                         return;
 733                 }
 734         }
 735         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
 736                 switch (sen) {
 737                 case SEN_write:
 738                 case SEN_pwrite:
 739                 case SEN_send:
 740                 case SEN_sendto:
 741                 case SEN_mq_timedsend:
 742                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 743                         break;
 744                 case SEN_writev:
 745                 case SEN_pwritev:
 746                 case SEN_pwritev2:
 747                 case SEN_vmsplice:
 748                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
 749                         break;
 750                 case SEN_sendmsg:
 751                         dumpiov_in_msghdr(tcp, tcp->u_arg[1],
 752                                           (unsigned long) -1L);
 753                         break;
 754                 case SEN_sendmmsg:
 755                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 756                         break;
 757                 }
 758         }
 759 }
 760
 761 /*
 762  * Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 763  * The shuffling should be an involution: shuffle_scno(shuffle_scno(n)) == n.
 764  */
 765 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
 766 static long
 767 shuffle_scno(unsigned long scno)
 768 {
 769         if (scno < ARM_FIRST_SHUFFLED_SYSCALL)
 770                 return scno;
 771
 772         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 773         if (scno == ARM_FIRST_SHUFFLED_SYSCALL)
 774                 return 0x000ffff0;
 775         if (scno == 0x000ffff0)
 776                 return ARM_FIRST_SHUFFLED_SYSCALL;
 777
 778 #define ARM_SECOND_SHUFFLED_SYSCALL (ARM_FIRST_SHUFFLED_SYSCALL + 1)
 779         /*
 780          * Is it ARM specific syscall?
 781          * Swap [0x000f0000, 0x000f0000 + LAST_SPECIAL] range
 782          * with [SECOND_SHUFFLED, SECOND_SHUFFLED + LAST_SPECIAL] range.
 783          */
 784         if (scno >= 0x000f0000 &&
 785             scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL) {
 786                 return scno - 0x000f0000 + ARM_SECOND_SHUFFLED_SYSCALL;
 787         }
 788         if (scno <= ARM_SECOND_SHUFFLED_SYSCALL + ARM_LAST_SPECIAL_SYSCALL) {
 789                 return scno + 0x000f0000 - ARM_SECOND_SHUFFLED_SYSCALL;
 790         }
 791
 792         return scno;
 793 }
 794 #else
 795 # define shuffle_scno(scno) ((long)(scno))
 796 #endif
 797
 798 const char *
 799 syscall_name(long scno)
 800 {
 801         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
 802
 803         if (SCNO_IS_VALID(scno))
 804                 return sysent[scno].sys_name;
 805         else {
 806                 sprintf(buf, "syscall_%lu", scno);
 807                 return buf;
 808         }
 809 }
 810
 811 const char *
 812 err_name(unsigned long err)
 813 {
 814         if ((err < nerrnos) && errnoent[err])
 815                 return errnoent[err];
 816
 817         return NULL;
 818 }
 819
 820 static long get_regs_error;
 821
 822 void
 823 clear_regs(void)
 824 {
 825         get_regs_error = -1;
 826 }
 827
 828 static int get_syscall_args(struct tcb *);
 829 static int get_syscall_result(struct tcb *);
 830 static int arch_get_scno(struct tcb *tcp);
 831 static void get_error(struct tcb *, const bool);
 832
 833 static int
 834 trace_syscall_entering(struct tcb *tcp)
 835 {
 836         int res, scno_good;
 837
 838         scno_good = res = get_scno(tcp);
 839         if (res == 0)
 840                 return res;
 841         if (res == 1)
 842                 res = get_syscall_args(tcp);
 843
 844         if (res != 1) {
 845                 printleader(tcp);
 846                 tprintf("%s(", scno_good == 1 ? tcp->s_ent->sys_name : "????");
 847                 /*
 848                  * " <unavailable>" will be added later by the code which
 849                  * detects ptrace errors.
 850                  */
 851                 goto ret;
 852         }
 853
 854 #ifdef LINUX_MIPSO32
 855         if (SEN_syscall == tcp->s_ent->sen)
 856                 decode_mips_subcall(tcp);
 857 #endif
 858
 859         if (   SEN_execve == tcp->s_ent->sen
 860 # if defined(SPARC) || defined(SPARC64)
 861             || SEN_execv == tcp->s_ent->sen
 862 # endif
 863            ) {
 864                 hide_log_until_execve = 0;
 865         }
 866
 867 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
 868         switch (tcp->s_ent->sen) {
 869 # ifdef SYS_socket_subcall
 870                 case SEN_socketcall:
 871                         decode_socket_subcall(tcp);
 872                         break;
 873 # endif
 874 # ifdef SYS_ipc_subcall
 875                 case SEN_ipc:
 876                         decode_ipc_subcall(tcp);
 877                         break;
 878 # endif
 879         }
 880 #endif
 881
 882         if (!(tcp->qual_flg & QUAL_TRACE)
 883          || (tracing_paths && !pathtrace_match(tcp))
 884         ) {
 885                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
 886                 tcp->sys_func_rval = 0;
 887                 return 0;
 888         }
 889
 890         tcp->flags &= ~TCB_FILTERED;
 891
 892         if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
 893                 res = 0;
 894                 goto ret;
 895         }
 896
 897 #ifdef USE_LIBUNWIND
 898         if (stack_trace_enabled) {
 899                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
 900                         unwind_capture_stacktrace(tcp);
 901         }
 902 #endif
 903
 904         printleader(tcp);
 905         tprintf("%s(", tcp->s_ent->sys_name);
 906         if ((tcp->qual_flg & QUAL_RAW) && SEN_exit != tcp->s_ent->sen)
 907                 res = printargs(tcp);
 908         else
 909                 res = tcp->s_ent->sys_func(tcp);
 910
 911         fflush(tcp->outf);
 912  ret:
 913         tcp->flags |= TCB_INSYSCALL;
 914         tcp->sys_func_rval = res;
 915         /* Measure the entrance time as late as possible to avoid errors. */
 916         if (Tflag || cflag)
 917                 gettimeofday(&tcp->etime, NULL);
 918         return res;
 919 }
 920
 921 static int
 922 trace_syscall_exiting(struct tcb *tcp)
 923 {
 924         int sys_res;
 925         struct timeval tv;
 926         int res;
 927         unsigned long u_error;
 928         const char *u_error_str;
 929
 930         /* Measure the exit time as early as possible to avoid errors. */
 931         if (Tflag || cflag)
 932                 gettimeofday(&tv, NULL);
 933
 934 #ifdef USE_LIBUNWIND
 935         if (stack_trace_enabled) {
 936                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
 937                         unwind_cache_invalidate(tcp);
 938         }
 939 #endif
 940
 941 #if SUPPORTED_PERSONALITIES > 1
 942         update_personality(tcp, tcp->currpers);
 943 #endif
 944         res = (get_regs_error ? -1 : get_syscall_result(tcp));
 945         if (filtered(tcp) || hide_log_until_execve)
 946                 goto ret;
 947
 948         if (cflag) {
 949                 count_syscall(tcp, &tv);
 950                 if (cflag == CFLAG_ONLY_STATS) {
 951                         goto ret;
 952                 }
 953         }
 954
 955         /* If not in -ff mode, and printing_tcp != tcp,
 956          * then the log currently does not end with output
 957          * of _our syscall entry_, but with something else.
 958          * We need to say which syscall's return is this.
 959          *
 960          * Forced reprinting via TCB_REPRINT is used only by
 961          * "strace -ff -oLOG test/threaded_execve" corner case.
 962          * It's the only case when -ff mode needs reprinting.
 963          */
 964         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
 965                 tcp->flags &= ~TCB_REPRINT;
 966                 printleader(tcp);
 967                 tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
 968         }
 969         printing_tcp = tcp;
 970
 971         tcp->s_prev_ent = NULL;
 972         if (res != 1) {
 973                 /* There was error in one of prior ptrace ops */
 974                 tprints(") ");
 975                 tabto();
 976                 tprints("= ? <unavailable>\n");
 977                 line_ended();
 978                 tcp->flags &= ~TCB_INSYSCALL;
 979                 tcp->sys_func_rval = 0;
 980                 free_tcb_priv_data(tcp);
 981                 return res;
 982         }
 983         tcp->s_prev_ent = tcp->s_ent;
 984
 985         sys_res = 0;
 986         if (tcp->qual_flg & QUAL_RAW) {
 987                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
 988         } else {
 989         /* FIXME: not_failing_only (IOW, option -z) is broken:
 990          * failure of syscall is known only after syscall return.
 991          * Thus we end up with something like this on, say, ENOENT:
 992          *     open("doesnt_exist", O_RDONLY <unfinished ...>
 993          *     {next syscall decode}
 994          * whereas the intended result is that open(...) line
 995          * is not shown at all.
 996          */
 997                 if (not_failing_only && tcp->u_error)
 998                         goto ret;       /* ignore failed syscalls */
 999                 if (tcp->sys_func_rval & RVAL_DECODED)
1000                         sys_res = tcp->sys_func_rval;
1001                 else
1002                         sys_res = tcp->s_ent->sys_func(tcp);
1003         }
1004
1005         tprints(") ");
1006         tabto();
1007         u_error = tcp->u_error;
1008         if (tcp->qual_flg & QUAL_RAW) {
1009                 if (u_error)
1010                         tprintf("= -1 (errno %lu)", u_error);
1011                 else
1012                         tprintf("= %#lx", tcp->u_rval);
1013         }
1014         else if (!(sys_res & RVAL_NONE) && u_error) {
1015                 switch (u_error) {
1016                 /* Blocked signals do not interrupt any syscalls.
1017                  * In this case syscalls don't return ERESTARTfoo codes.
1018                  *
1019                  * Deadly signals set to SIG_DFL interrupt syscalls
1020                  * and kill the process regardless of which of the codes below
1021                  * is returned by the interrupted syscall.
1022                  * In some cases, kernel forces a kernel-generated deadly
1023                  * signal to be unblocked and set to SIG_DFL (and thus cause
1024                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
1025                  * or SIGILL. (The alternative is to leave process spinning
1026                  * forever on the faulty instruction - not useful).
1027                  *
1028                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
1029                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
1030                  * but kernel will always restart them.
1031                  */
1032                 case ERESTARTSYS:
1033                         /* Most common type of signal-interrupted syscall exit code.
1034                          * The system call will be restarted with the same arguments
1035                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
1036                          */
1037                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
1038                         break;
1039                 case ERESTARTNOINTR:
1040                         /* Rare. For example, fork() returns this if interrupted.
1041                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
1042                          */
1043                         tprints("= ? ERESTARTNOINTR (To be restarted)");
1044                         break;
1045                 case ERESTARTNOHAND:
1046                         /* pause(), rt_sigsuspend() etc use this code.
1047                          * SA_RESTART is ignored (assumed not set):
1048                          * syscall won't restart (will return EINTR instead)
1049                          * even after signal with SA_RESTART set. However,
1050                          * after SIG_IGN or SIG_DFL signal it will restart
1051                          * (thus the name "restart only if has no handler").
1052                          */
1053                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
1054                         break;
1055                 case ERESTART_RESTARTBLOCK:
1056                         /* Syscalls like nanosleep(), poll() which can't be
1057                          * restarted with their original arguments use this
1058                          * code. Kernel will execute restart_syscall() instead,
1059                          * which changes arguments before restarting syscall.
1060                          * SA_RESTART is ignored (assumed not set) similarly
1061                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
1062                          * since restart data is saved in "restart block"
1063                          * in task struct, and if signal handler uses a syscall
1064                          * which in turn saves another such restart block,
1065                          * old data is lost and restart becomes impossible)
1066                          */
1067                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
1068                         break;
1069                 default:
1070                         u_error_str = err_name(u_error);
1071                         if (u_error_str)
1072                                 tprintf("= -1 %s (%s)",
1073                                         u_error_str, strerror(u_error));
1074                         else
1075                                 tprintf("= -1 %lu (%s)",
1076                                         u_error, strerror(u_error));
1077                         break;
1078                 }
1079                 if ((sys_res & RVAL_STR) && tcp->auxstr)
1080                         tprintf(" (%s)", tcp->auxstr);
1081         }
1082         else {
1083                 if (sys_res & RVAL_NONE)
1084                         tprints("= ?");
1085                 else {
1086                         switch (sys_res & RVAL_MASK) {
1087                         case RVAL_HEX:
1088 #if SUPPORTED_PERSONALITIES > 1
1089                                 if (current_wordsize < sizeof(long))
1090                                         tprintf("= %#x",
1091                                                 (unsigned int) tcp->u_rval);
1092                                 else
1093 #endif
1094                                         tprintf("= %#lx", tcp->u_rval);
1095                                 break;
1096                         case RVAL_OCTAL:
1097                                 tprints("= ");
1098                                 print_numeric_long_umask(tcp->u_rval);
1099                                 break;
1100                         case RVAL_UDECIMAL:
1101 #if SUPPORTED_PERSONALITIES > 1
1102                                 if (current_wordsize < sizeof(long))
1103                                         tprintf("= %u",
1104                                                 (unsigned int) tcp->u_rval);
1105                                 else
1106 #endif
1107                                         tprintf("= %lu", tcp->u_rval);
1108                                 break;
1109                         case RVAL_DECIMAL:
1110                                 tprintf("= %ld", tcp->u_rval);
1111                                 break;
1112                         case RVAL_FD:
1113                                 if (show_fd_path) {
1114                                         tprints("= ");
1115                                         printfd(tcp, tcp->u_rval);
1116                                 }
1117                                 else
1118                                         tprintf("= %ld", tcp->u_rval);
1119                                 break;
1120 #if HAVE_STRUCT_TCB_EXT_ARG
1121                         /*
1122                         case RVAL_LHEX:
1123                                 tprintf("= %#llx", tcp->u_lrval);
1124                                 break;
1125                         case RVAL_LOCTAL:
1126                                 tprintf("= %#llo", tcp->u_lrval);
1127                                 break;
1128                         */
1129                         case RVAL_LUDECIMAL:
1130                                 tprintf("= %llu", tcp->u_lrval);
1131                                 break;
1132                         /*
1133                         case RVAL_LDECIMAL:
1134                                 tprintf("= %lld", tcp->u_lrval);
1135                                 break;
1136                         */
1137 #endif /* HAVE_STRUCT_TCB_EXT_ARG */
1138                         default:
1139                                 error_msg("invalid rval format");
1140                                 break;
1141                         }
1142                 }
1143                 if ((sys_res & RVAL_STR) && tcp->auxstr)
1144                         tprintf(" (%s)", tcp->auxstr);
1145         }
1146         if (Tflag) {
1147                 tv_sub(&tv, &tv, &tcp->etime);
1148                 tprintf(" <%ld.%06ld>",
1149                         (long) tv.tv_sec, (long) tv.tv_usec);
1150         }
1151         tprints("\n");
1152         dumpio(tcp);
1153         line_ended();
1154
1155 #ifdef USE_LIBUNWIND
1156         if (stack_trace_enabled)
1157                 unwind_print_stacktrace(tcp);
1158 #endif
1159
1160  ret:
1161         tcp->flags &= ~TCB_INSYSCALL;
1162         tcp->sys_func_rval = 0;
1163         free_tcb_priv_data(tcp);
1164         return 0;
1165 }
1166
1167 int
1168 trace_syscall(struct tcb *tcp)
1169 {
1170         return exiting(tcp) ?
1171                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
1172 }
1173
1174 bool
1175 is_erestart(struct tcb *tcp)
1176 {
1177         switch (tcp->u_error) {
1178                 case ERESTARTSYS:
1179                 case ERESTARTNOINTR:
1180                 case ERESTARTNOHAND:
1181                 case ERESTART_RESTARTBLOCK:
1182                         return true;
1183                 default:
1184                         return false;
1185         }
1186 }
1187
1188 static unsigned long saved_u_error;
1189
1190 void
1191 temporarily_clear_syserror(struct tcb *tcp)
1192 {
1193         saved_u_error = tcp->u_error;
1194         tcp->u_error = 0;
1195 }
1196
1197 void
1198 restore_cleared_syserror(struct tcb *tcp)
1199 {
1200         tcp->u_error = saved_u_error;
1201 }
1202
1203 #include "kernel_types.h"
1204
1205 /*
1206  * Check the syscall return value register value for whether it is
1207  * a negated errno code indicating an error, or a success return value.
1208  */
1209 static inline bool
1210 is_negated_errno(kernel_ulong_t val)
1211 {
1212         /* Linux kernel defines MAX_ERRNO to 4095. */
1213         kernel_ulong_t max = -(kernel_long_t) 4095;
1214
1215 #if defined X86_64 || defined X32
1216         /*
1217          * current_wordsize is 4 for x32 personality
1218          * but truncation _must not_ be done in it, so
1219          * check current_personality instead.
1220          */
1221         if (current_personality == 1) {
1222                 val = (uint32_t) val;
1223                 max = (uint32_t) max;
1224         }
1225 #elif SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
1226         if (current_wordsize < sizeof(val)) {
1227                 val = (uint32_t) val;
1228                 max = (uint32_t) max;
1229         }
1230 #endif
1231
1232         return val >= max;
1233 }
1234
1235 #include "arch_regs.c"
1236
1237 #ifdef HAVE_GETRVAL2
1238 # include "arch_getrval2.c"
1239 #endif
1240
1241 void
1242 print_pc(struct tcb *tcp)
1243 {
1244 #if defined ARCH_PC_REG
1245 # define ARCH_GET_PC 0
1246 #elif defined ARCH_PC_PEEK_ADDR
1247         long pc;
1248 # define ARCH_PC_REG pc
1249 # define ARCH_GET_PC upeek(tcp->pid, ARCH_PC_PEEK_ADDR, &pc)
1250 #else
1251 # error Neither ARCH_PC_REG nor ARCH_PC_PEEK_ADDR is defined
1252 #endif
1253         if (get_regs_error || ARCH_GET_PC)
1254                 tprints(current_wordsize == 4 ? "[????????] "
1255                                               : "[????????????????] ");
1256         else
1257                 tprintf(current_wordsize == 4 ? "[%08lx] " : "[%016lx] ",
1258                         (unsigned long) ARCH_PC_REG);
1259 }
1260
1261 #include "getregs_old.h"
1262
1263 #undef ptrace_getregset_or_getregs
1264 #ifdef ARCH_REGS_FOR_GETREGSET
1265
1266 # define ptrace_getregset_or_getregs ptrace_getregset
1267 static long
1268 ptrace_getregset(pid_t pid)
1269 {
1270 # ifdef ARCH_IOVEC_FOR_GETREGSET
1271         /* variable iovec */
1272         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1273         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1274                       &ARCH_IOVEC_FOR_GETREGSET);
1275 # else
1276         /* constant iovec */
1277         static struct iovec io = {
1278                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1279                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1280         };
1281         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1282
1283 # endif
1284 }
1285
1286 #elif defined ARCH_REGS_FOR_GETREGS
1287
1288 # define ptrace_getregset_or_getregs ptrace_getregs
1289 static long
1290 ptrace_getregs(pid_t pid)
1291 {
1292 # if defined SPARC || defined SPARC64
1293         /* SPARC systems have the meaning of data and addr reversed */
1294         return ptrace(PTRACE_GETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1295 # else
1296         return ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1297 # endif
1298 }
1299
1300 #endif /* ARCH_REGS_FOR_GETREGSET || ARCH_REGS_FOR_GETREGS */
1301
1302 void
1303 get_regs(pid_t pid)
1304 {
1305 #undef USE_GET_SYSCALL_RESULT_REGS
1306 #ifdef ptrace_getregset_or_getregs
1307
1308 # ifdef HAVE_GETREGS_OLD
1309         /*
1310          * Try PTRACE_GETREGSET/PTRACE_GETREGS first,
1311          * fallback to getregs_old.
1312          */
1313         static int use_getregs_old;
1314         if (use_getregs_old < 0) {
1315                 get_regs_error = ptrace_getregset_or_getregs(pid);
1316                 return;
1317         } else if (use_getregs_old == 0) {
1318                 get_regs_error = ptrace_getregset_or_getregs(pid);
1319                 if (get_regs_error >= 0) {
1320                         use_getregs_old = -1;
1321                         return;
1322                 }
1323                 if (errno == EPERM || errno == ESRCH)
1324                         return;
1325                 use_getregs_old = 1;
1326         }
1327         get_regs_error = getregs_old(pid);
1328 # else /* !HAVE_GETREGS_OLD */
1329         /* Assume that PTRACE_GETREGSET/PTRACE_GETREGS works. */
1330         get_regs_error = ptrace_getregset_or_getregs(pid);
1331 # endif /* !HAVE_GETREGS_OLD */
1332
1333 #else /* !ptrace_getregset_or_getregs */
1334
1335 # define USE_GET_SYSCALL_RESULT_REGS 1
1336 # warning get_regs is not implemented for this architecture yet
1337         get_regs_error = 0;
1338
1339 #endif /* !ptrace_getregset_or_getregs */
1340 }
1341
1342 struct sysent_buf {
1343         struct tcb *tcp;
1344         struct_sysent ent;
1345         char buf[sizeof("syscall_%lu") + sizeof(long) * 3];
1346 };
1347
1348 static void
1349 free_sysent_buf(void *ptr)
1350 {
1351         struct sysent_buf *s = ptr;
1352         s->tcp->s_prev_ent = s->tcp->s_ent = NULL;
1353         free(ptr);
1354 }
1355
1356 /*
1357  * Returns:
1358  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1359  * 1: ok, continue in trace_syscall_entering().
1360  * other: error, trace_syscall_entering() should print error indicator
1361  *    ("????" etc) and bail out.
1362  */
1363 int
1364 get_scno(struct tcb *tcp)
1365 {
1366         if (get_regs_error)
1367                 return -1;
1368
1369         int rc = arch_get_scno(tcp);
1370         if (rc != 1)
1371                 return rc;
1372
1373         if (SCNO_IS_VALID(tcp->scno)) {
1374                 tcp->s_ent = &sysent[tcp->scno];
1375                 tcp->qual_flg = qual_flags[tcp->scno];
1376         } else {
1377                 struct sysent_buf *s = xcalloc(1, sizeof(*s));
1378
1379                 s->tcp = tcp;
1380                 s->ent.nargs = MAX_ARGS;
1381                 s->ent.sen = SEN_printargs;
1382                 s->ent.sys_func = printargs;
1383                 s->ent.sys_name = s->buf;
1384                 sprintf(s->buf, "syscall_%lu", shuffle_scno(tcp->scno));
1385
1386                 tcp->s_ent = &s->ent;
1387                 tcp->qual_flg = QUAL_RAW | DEFAULT_QUAL_FLAGS;
1388
1389                 set_tcb_priv_data(tcp, s, free_sysent_buf);
1390
1391                 if (debug_flag)
1392                         error_msg("pid %d invalid syscall %ld", tcp->pid, tcp->scno);
1393         }
1394         return 1;
1395 }
1396
1397 #ifdef USE_GET_SYSCALL_RESULT_REGS
1398 static int get_syscall_result_regs(struct tcb *);
1399 #endif
1400
1401 /* Returns:
1402  * 1: ok, continue in trace_syscall_exiting().
1403  * -1: error, trace_syscall_exiting() should print error indicator
1404  *    ("????" etc) and bail out.
1405  */
1406 static int
1407 get_syscall_result(struct tcb *tcp)
1408 {
1409 #ifdef USE_GET_SYSCALL_RESULT_REGS
1410         if (get_syscall_result_regs(tcp))
1411                 return -1;
1412 #endif
1413         tcp->u_error = 0;
1414         get_error(tcp, !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS));
1415
1416         return 1;
1417 }
1418
1419 #include "get_scno.c"
1420 #include "get_syscall_args.c"
1421 #ifdef USE_GET_SYSCALL_RESULT_REGS
1422 # include "get_syscall_result.c"
1423 #endif
1424 #include "get_error.c"
1425 #ifdef HAVE_GETREGS_OLD
1426 # include "getregs_old.c"
1427 #endif