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_syscall(), qual_signal(), qual_desc();
 363
 364 static const struct qual_options {
 365         unsigned int bitflag;
 366         const char *option_name;
 367         int (*qualify)(const char *, int, int);
 368         const char *argument_name;
 369 } qual_options[] = {
 370         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
 371         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
 372         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
 373         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
 374         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
 375         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
 376         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
 377         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
 378         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
 379         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
 380         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
 381         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
 382         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
 383         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
 384         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
 385         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
 386         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
 387         { 0,            NULL,           NULL,           NULL            },
 388 };
 389
 390 static void
 391 reallocate_qual(const unsigned int n)
 392 {
 393         unsigned p;
 394         qualbits_t *qp;
 395         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 396                 qp = qual_vec[p] = xreallocarray(qual_vec[p], n,
 397                                                  sizeof(qualbits_t));
 398                 memset(&qp[num_quals], 0, (n - num_quals) * sizeof(qualbits_t));
 399         }
 400         num_quals = n;
 401 }
 402
 403 static void
 404 qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
 405 {
 406         int p;
 407
 408         if (num_quals <= n)
 409                 reallocate_qual(n + 1);
 410
 411         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 412                 if (pers == p || pers < 0) {
 413                         if (not)
 414                                 qual_vec[p][n] &= ~bitflag;
 415                         else
 416                                 qual_vec[p][n] |= bitflag;
 417                 }
 418         }
 419 }
 420
 421 static int
 422 qual_syscall(const char *s, const unsigned int bitflag, const int not)
 423 {
 424         int p;
 425         unsigned int i;
 426         int rc = -1;
 427
 428         if (*s >= '0' && *s <= '9') {
 429                 i = string_to_uint(s);
 430                 if (i >= MAX_NSYSCALLS)
 431                         return -1;
 432                 qualify_one(i, bitflag, not, -1);
 433                 return 0;
 434         }
 435
 436         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
 437                 for (i = 0; i < nsyscall_vec[p]; i++) {
 438                         if (sysent_vec[p][i].sys_name
 439                          && strcmp(s, sysent_vec[p][i].sys_name) == 0
 440                         ) {
 441                                 qualify_one(i, bitflag, not, p);
 442                                 rc = 0;
 443                         }
 444                 }
 445         }
 446
 447         return rc;
 448 }
 449
 450 static int
 451 qual_signal(const char *s, const unsigned int bitflag, const int not)
 452 {
 453         unsigned int i;
 454
 455         if (*s >= '0' && *s <= '9') {
 456                 int signo = string_to_uint(s);
 457                 if (signo < 0 || signo > 255)
 458                         return -1;
 459                 qualify_one(signo, bitflag, not, -1);
 460                 return 0;
 461         }
 462         if (strncasecmp(s, "SIG", 3) == 0)
 463                 s += 3;
 464         for (i = 0; i <= NSIG; i++) {
 465                 if (strcasecmp(s, signame(i) + 3) == 0) {
 466                         qualify_one(i, bitflag, not, -1);
 467                         return 0;
 468                 }
 469         }
 470         return -1;
 471 }
 472
 473 static int
 474 qual_desc(const char *s, const unsigned int bitflag, const int not)
 475 {
 476         if (*s >= '0' && *s <= '9') {
 477                 int desc = string_to_uint(s);
 478                 if (desc < 0 || desc > 0x7fff) /* paranoia */
 479                         return -1;
 480                 qualify_one(desc, bitflag, not, -1);
 481                 return 0;
 482         }
 483         return -1;
 484 }
 485
 486 static int
 487 lookup_class(const char *s)
 488 {
 489         if (strcmp(s, "file") == 0)
 490                 return TRACE_FILE;
 491         if (strcmp(s, "ipc") == 0)
 492                 return TRACE_IPC;
 493         if (strcmp(s, "network") == 0)
 494                 return TRACE_NETWORK;
 495         if (strcmp(s, "process") == 0)
 496                 return TRACE_PROCESS;
 497         if (strcmp(s, "signal") == 0)
 498                 return TRACE_SIGNAL;
 499         if (strcmp(s, "desc") == 0)
 500                 return TRACE_DESC;
 501         if (strcmp(s, "memory") == 0)
 502                 return TRACE_MEMORY;
 503         return -1;
 504 }
 505
 506 void
 507 qualify(const char *s)
 508 {
 509         const struct qual_options *opt;
 510         char *copy;
 511         const char *p;
 512         int not;
 513         unsigned int i;
 514
 515         if (num_quals == 0)
 516                 reallocate_qual(MIN_QUALS);
 517
 518         opt = &qual_options[0];
 519         for (i = 0; (p = qual_options[i].option_name); i++) {
 520                 unsigned int len = strlen(p);
 521                 if (strncmp(s, p, len) == 0 && s[len] == '=') {
 522                         opt = &qual_options[i];
 523                         s += len + 1;
 524                         break;
 525                 }
 526         }
 527         not = 0;
 528         if (*s == '!') {
 529                 not = 1;
 530                 s++;
 531         }
 532         if (strcmp(s, "none") == 0) {
 533                 not = 1 - not;
 534                 s = "all";
 535         }
 536         if (strcmp(s, "all") == 0) {
 537                 for (i = 0; i < num_quals; i++) {
 538                         qualify_one(i, opt->bitflag, not, -1);
 539                 }
 540                 return;
 541         }
 542         for (i = 0; i < num_quals; i++) {
 543                 qualify_one(i, opt->bitflag, !not, -1);
 544         }
 545         copy = xstrdup(s);
 546         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
 547                 int n;
 548                 if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
 549                         unsigned pers;
 550                         for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
 551                                 for (i = 0; i < nsyscall_vec[pers]; i++)
 552                                         if (sysent_vec[pers][i].sys_flags & n)
 553                                                 qualify_one(i, opt->bitflag, not, pers);
 554                         }
 555                         continue;
 556                 }
 557                 if (opt->qualify(p, opt->bitflag, not)) {
 558                         error_msg_and_die("invalid %s '%s'",
 559                                 opt->argument_name, p);
 560                 }
 561         }
 562         free(copy);
 563         return;
 564 }
 565
 566 #ifdef SYS_socket_subcall
 567 static void
 568 decode_socket_subcall(struct tcb *tcp)
 569 {
 570         unsigned long addr;
 571         unsigned int n;
 572
 573         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_socket_nsubcalls)
 574                 return;
 575
 576         tcp->scno = SYS_socket_subcall + tcp->u_arg[0];
 577         tcp->qual_flg = qual_flags[tcp->scno];
 578         tcp->s_ent = &sysent[tcp->scno];
 579         addr = tcp->u_arg[1];
 580         n = tcp->s_ent->nargs;
 581         if (sizeof(tcp->u_arg[0]) == current_wordsize) {
 582                 memset(tcp->u_arg, 0, n * sizeof(tcp->u_arg[0]));
 583                 (void) umoven(tcp, addr, n * sizeof(tcp->u_arg[0]), tcp->u_arg);
 584         } else {
 585                 unsigned int args[n];
 586                 unsigned int i;
 587
 588                 memset(args, 0, sizeof(args));
 589                 (void) umove(tcp, addr, &args);
 590                 for (i = 0; i < n; ++i)
 591                         tcp->u_arg[i] = args[i];
 592         }
 593 }
 594 #endif
 595
 596 #ifdef SYS_ipc_subcall
 597 static void
 598 decode_ipc_subcall(struct tcb *tcp)
 599 {
 600         unsigned int i, n;
 601
 602         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_ipc_nsubcalls)
 603                 return;
 604
 605         tcp->scno = SYS_ipc_subcall + tcp->u_arg[0];
 606         tcp->qual_flg = qual_flags[tcp->scno];
 607         tcp->s_ent = &sysent[tcp->scno];
 608         n = tcp->s_ent->nargs;
 609         for (i = 0; i < n; i++)
 610                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 611 }
 612 #endif
 613
 614 #ifdef LINUX_MIPSO32
 615 static void
 616 decode_mips_subcall(struct tcb *tcp)
 617 {
 618         if (!SCNO_IS_VALID(tcp->u_arg[0]))
 619                 return;
 620         tcp->scno = tcp->u_arg[0];
 621         tcp->qual_flg = qual_flags[tcp->scno];
 622         tcp->s_ent = &sysent[tcp->scno];
 623         memmove(&tcp->u_arg[0], &tcp->u_arg[1],
 624                 sizeof(tcp->u_arg) - sizeof(tcp->u_arg[0]));
 625         /*
 626          * Fetching the last arg of 7-arg syscalls (fadvise64_64
 627          * and sync_file_range) would require additional code,
 628          * see linux/mips/get_syscall_args.c
 629          */
 630 }
 631 #endif
 632
 633 static void
 634 dumpio(struct tcb *tcp)
 635 {
 636         int sen;
 637
 638         if (syserror(tcp))
 639                 return;
 640         if ((unsigned long) tcp->u_arg[0] >= num_quals)
 641                 return;
 642         sen = tcp->s_ent->sen;
 643         if (SEN_printargs == sen)
 644                 return;
 645         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
 646                 switch (sen) {
 647                 case SEN_read:
 648                 case SEN_pread:
 649                 case SEN_recv:
 650                 case SEN_recvfrom:
 651                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
 652                         return;
 653                 case SEN_readv:
 654                 case SEN_preadv:
 655                 case SEN_preadv2:
 656                         dumpiov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1],
 657                                      tcp->u_rval);
 658                         return;
 659                 case SEN_recvmsg:
 660                         dumpiov_in_msghdr(tcp, tcp->u_arg[1], tcp->u_rval);
 661                         return;
 662                 case SEN_recvmmsg:
 663                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 664                         return;
 665                 }
 666         }
 667         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
 668                 switch (sen) {
 669                 case SEN_write:
 670                 case SEN_pwrite:
 671                 case SEN_send:
 672                 case SEN_sendto:
 673                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 674                         break;
 675                 case SEN_writev:
 676                 case SEN_pwritev:
 677                 case SEN_pwritev2:
 678                 case SEN_vmsplice:
 679                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
 680                         break;
 681                 case SEN_sendmsg:
 682                         dumpiov_in_msghdr(tcp, tcp->u_arg[1],
 683                                           (unsigned long) -1L);
 684                         break;
 685                 case SEN_sendmmsg:
 686                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 687                         break;
 688                 }
 689         }
 690 }
 691
 692 /*
 693  * Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 694  * The shuffling should be an involution: shuffle_scno(shuffle_scno(n)) == n.
 695  */
 696 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
 697 static long
 698 shuffle_scno(unsigned long scno)
 699 {
 700         if (scno < ARM_FIRST_SHUFFLED_SYSCALL)
 701                 return scno;
 702
 703         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 704         if (scno == ARM_FIRST_SHUFFLED_SYSCALL)
 705                 return 0x000ffff0;
 706         if (scno == 0x000ffff0)
 707                 return ARM_FIRST_SHUFFLED_SYSCALL;
 708
 709 #define ARM_SECOND_SHUFFLED_SYSCALL (ARM_FIRST_SHUFFLED_SYSCALL + 1)
 710         /*
 711          * Is it ARM specific syscall?
 712          * Swap [0x000f0000, 0x000f0000 + LAST_SPECIAL] range
 713          * with [SECOND_SHUFFLED, SECOND_SHUFFLED + LAST_SPECIAL] range.
 714          */
 715         if (scno >= 0x000f0000 &&
 716             scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL) {
 717                 return scno - 0x000f0000 + ARM_SECOND_SHUFFLED_SYSCALL;
 718         }
 719         if (scno <= ARM_SECOND_SHUFFLED_SYSCALL + ARM_LAST_SPECIAL_SYSCALL) {
 720                 return scno + 0x000f0000 - ARM_SECOND_SHUFFLED_SYSCALL;
 721         }
 722
 723         return scno;
 724 }
 725 #else
 726 # define shuffle_scno(scno) ((long)(scno))
 727 #endif
 728
 729 const char *
 730 syscall_name(long scno)
 731 {
 732         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
 733
 734         if (SCNO_IS_VALID(scno))
 735                 return sysent[scno].sys_name;
 736         else {
 737                 sprintf(buf, "syscall_%lu", shuffle_scno(scno));
 738                 return buf;
 739         }
 740 }
 741
 742 static long get_regs_error;
 743
 744 void
 745 clear_regs(void)
 746 {
 747         get_regs_error = -1;
 748 }
 749
 750 static int get_syscall_args(struct tcb *);
 751 static int get_syscall_result(struct tcb *);
 752 static int arch_get_scno(struct tcb *tcp);
 753 static void get_error(struct tcb *, const bool);
 754 #if defined X86_64 || defined POWERPC
 755 static int getregs_old(pid_t);
 756 #endif
 757
 758 static int
 759 trace_syscall_entering(struct tcb *tcp)
 760 {
 761         int res, scno_good;
 762
 763         scno_good = res = get_scno(tcp);
 764         if (res == 0)
 765                 return res;
 766         if (res == 1)
 767                 res = get_syscall_args(tcp);
 768
 769         if (res != 1) {
 770                 printleader(tcp);
 771                 if (scno_good != 1)
 772                         tprints("????" /* anti-trigraph gap */ "(");
 773                 else
 774                         tprintf("%s(", syscall_name(tcp->scno));
 775                 /*
 776                  * " <unavailable>" will be added later by the code which
 777                  * detects ptrace errors.
 778                  */
 779                 goto ret;
 780         }
 781
 782 #ifdef LINUX_MIPSO32
 783         if (SEN_syscall == tcp->s_ent->sen)
 784                 decode_mips_subcall(tcp);
 785 #endif
 786
 787         if (   SEN_execve == tcp->s_ent->sen
 788 # if defined(SPARC) || defined(SPARC64)
 789             || SEN_execv == tcp->s_ent->sen
 790 # endif
 791            ) {
 792                 hide_log_until_execve = 0;
 793         }
 794
 795 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
 796         switch (tcp->s_ent->sen) {
 797 # ifdef SYS_socket_subcall
 798                 case SEN_socketcall:
 799                         decode_socket_subcall(tcp);
 800                         break;
 801 # endif
 802 # ifdef SYS_ipc_subcall
 803                 case SEN_ipc:
 804                         decode_ipc_subcall(tcp);
 805                         break;
 806 # endif
 807         }
 808 #endif
 809
 810         if (!(tcp->qual_flg & QUAL_TRACE)
 811          || (tracing_paths && !pathtrace_match(tcp))
 812         ) {
 813                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
 814                 tcp->sys_func_rval = 0;
 815                 return 0;
 816         }
 817
 818         tcp->flags &= ~TCB_FILTERED;
 819
 820         if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
 821                 res = 0;
 822                 goto ret;
 823         }
 824
 825 #ifdef USE_LIBUNWIND
 826         if (stack_trace_enabled) {
 827                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
 828                         unwind_capture_stacktrace(tcp);
 829         }
 830 #endif
 831
 832         printleader(tcp);
 833         tprintf("%s(", syscall_name(tcp->scno));
 834         if ((tcp->qual_flg & QUAL_RAW) && SEN_exit != tcp->s_ent->sen)
 835                 res = printargs(tcp);
 836         else
 837                 res = tcp->s_ent->sys_func(tcp);
 838
 839         fflush(tcp->outf);
 840  ret:
 841         tcp->flags |= TCB_INSYSCALL;
 842         tcp->sys_func_rval = res;
 843         /* Measure the entrance time as late as possible to avoid errors. */
 844         if (Tflag || cflag)
 845                 gettimeofday(&tcp->etime, NULL);
 846         return res;
 847 }
 848
 849 static int
 850 trace_syscall_exiting(struct tcb *tcp)
 851 {
 852         int sys_res;
 853         struct timeval tv;
 854         int res;
 855         long u_error;
 856
 857         /* Measure the exit time as early as possible to avoid errors. */
 858         if (Tflag || cflag)
 859                 gettimeofday(&tv, NULL);
 860
 861 #ifdef USE_LIBUNWIND
 862         if (stack_trace_enabled) {
 863                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
 864                         unwind_cache_invalidate(tcp);
 865         }
 866 #endif
 867
 868 #if SUPPORTED_PERSONALITIES > 1
 869         update_personality(tcp, tcp->currpers);
 870 #endif
 871         res = (get_regs_error ? -1 : get_syscall_result(tcp));
 872         if (filtered(tcp) || hide_log_until_execve)
 873                 goto ret;
 874
 875         if (cflag) {
 876                 count_syscall(tcp, &tv);
 877                 if (cflag == CFLAG_ONLY_STATS) {
 878                         goto ret;
 879                 }
 880         }
 881
 882         /* If not in -ff mode, and printing_tcp != tcp,
 883          * then the log currently does not end with output
 884          * of _our syscall entry_, but with something else.
 885          * We need to say which syscall's return is this.
 886          *
 887          * Forced reprinting via TCB_REPRINT is used only by
 888          * "strace -ff -oLOG test/threaded_execve" corner case.
 889          * It's the only case when -ff mode needs reprinting.
 890          */
 891         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
 892                 tcp->flags &= ~TCB_REPRINT;
 893                 printleader(tcp);
 894                 tprintf("<... %s resumed> ", syscall_name(tcp->scno));
 895         }
 896         printing_tcp = tcp;
 897
 898         tcp->s_prev_ent = NULL;
 899         if (res != 1) {
 900                 /* There was error in one of prior ptrace ops */
 901                 tprints(") ");
 902                 tabto();
 903                 tprints("= ? <unavailable>\n");
 904                 line_ended();
 905                 tcp->flags &= ~TCB_INSYSCALL;
 906                 tcp->sys_func_rval = 0;
 907                 return res;
 908         }
 909         tcp->s_prev_ent = tcp->s_ent;
 910
 911         sys_res = 0;
 912         if (tcp->qual_flg & QUAL_RAW) {
 913                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
 914         } else {
 915         /* FIXME: not_failing_only (IOW, option -z) is broken:
 916          * failure of syscall is known only after syscall return.
 917          * Thus we end up with something like this on, say, ENOENT:
 918          *     open("doesnt_exist", O_RDONLY <unfinished ...>
 919          *     {next syscall decode}
 920          * whereas the intended result is that open(...) line
 921          * is not shown at all.
 922          */
 923                 if (not_failing_only && tcp->u_error)
 924                         goto ret;       /* ignore failed syscalls */
 925                 if (tcp->sys_func_rval & RVAL_DECODED)
 926                         sys_res = tcp->sys_func_rval;
 927                 else
 928                         sys_res = tcp->s_ent->sys_func(tcp);
 929         }
 930
 931         tprints(") ");
 932         tabto();
 933         u_error = tcp->u_error;
 934         if (tcp->qual_flg & QUAL_RAW) {
 935                 if (u_error)
 936                         tprintf("= -1 (errno %ld)", u_error);
 937                 else
 938                         tprintf("= %#lx", tcp->u_rval);
 939         }
 940         else if (!(sys_res & RVAL_NONE) && u_error) {
 941                 switch (u_error) {
 942                 /* Blocked signals do not interrupt any syscalls.
 943                  * In this case syscalls don't return ERESTARTfoo codes.
 944                  *
 945                  * Deadly signals set to SIG_DFL interrupt syscalls
 946                  * and kill the process regardless of which of the codes below
 947                  * is returned by the interrupted syscall.
 948                  * In some cases, kernel forces a kernel-generated deadly
 949                  * signal to be unblocked and set to SIG_DFL (and thus cause
 950                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
 951                  * or SIGILL. (The alternative is to leave process spinning
 952                  * forever on the faulty instruction - not useful).
 953                  *
 954                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
 955                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
 956                  * but kernel will always restart them.
 957                  */
 958                 case ERESTARTSYS:
 959                         /* Most common type of signal-interrupted syscall exit code.
 960                          * The system call will be restarted with the same arguments
 961                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
 962                          */
 963                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
 964                         break;
 965                 case ERESTARTNOINTR:
 966                         /* Rare. For example, fork() returns this if interrupted.
 967                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
 968                          */
 969                         tprints("= ? ERESTARTNOINTR (To be restarted)");
 970                         break;
 971                 case ERESTARTNOHAND:
 972                         /* pause(), rt_sigsuspend() etc use this code.
 973                          * SA_RESTART is ignored (assumed not set):
 974                          * syscall won't restart (will return EINTR instead)
 975                          * even after signal with SA_RESTART set. However,
 976                          * after SIG_IGN or SIG_DFL signal it will restart
 977                          * (thus the name "restart only if has no handler").
 978                          */
 979                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
 980                         break;
 981                 case ERESTART_RESTARTBLOCK:
 982                         /* Syscalls like nanosleep(), poll() which can't be
 983                          * restarted with their original arguments use this
 984                          * code. Kernel will execute restart_syscall() instead,
 985                          * which changes arguments before restarting syscall.
 986                          * SA_RESTART is ignored (assumed not set) similarly
 987                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
 988                          * since restart data is saved in "restart block"
 989                          * in task struct, and if signal handler uses a syscall
 990                          * which in turn saves another such restart block,
 991                          * old data is lost and restart becomes impossible)
 992                          */
 993                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
 994                         break;
 995                 default:
 996                         if ((unsigned long) u_error < nerrnos
 997                             && errnoent[u_error])
 998                                 tprintf("= -1 %s (%s)", errnoent[u_error],
 999                                         strerror(u_error));
1000                         else
1001                                 tprintf("= -1 ERRNO_%lu (%s)", u_error,
1002                                         strerror(u_error));
1003                         break;
1004                 }
1005                 if ((sys_res & RVAL_STR) && tcp->auxstr)
1006                         tprintf(" (%s)", tcp->auxstr);
1007         }
1008         else {
1009                 if (sys_res & RVAL_NONE)
1010                         tprints("= ?");
1011                 else {
1012                         switch (sys_res & RVAL_MASK) {
1013                         case RVAL_HEX:
1014 #if SUPPORTED_PERSONALITIES > 1
1015                                 if (current_wordsize < sizeof(long))
1016                                         tprintf("= %#x",
1017                                                 (unsigned int) tcp->u_rval);
1018                                 else
1019 #endif
1020                                         tprintf("= %#lx", tcp->u_rval);
1021                                 break;
1022                         case RVAL_OCTAL:
1023                                 tprintf("= %#lo", tcp->u_rval);
1024                                 break;
1025                         case RVAL_UDECIMAL:
1026 #if SUPPORTED_PERSONALITIES > 1
1027                                 if (current_wordsize < sizeof(long))
1028                                         tprintf("= %u",
1029                                                 (unsigned int) tcp->u_rval);
1030                                 else
1031 #endif
1032                                         tprintf("= %lu", tcp->u_rval);
1033                                 break;
1034                         case RVAL_DECIMAL:
1035                                 tprintf("= %ld", tcp->u_rval);
1036                                 break;
1037                         case RVAL_FD:
1038                                 if (show_fd_path) {
1039                                         tprints("= ");
1040                                         printfd(tcp, tcp->u_rval);
1041                                 }
1042                                 else
1043                                         tprintf("= %ld", tcp->u_rval);
1044                                 break;
1045 #if HAVE_STRUCT_TCB_EXT_ARG
1046                         /*
1047                         case RVAL_LHEX:
1048                                 tprintf("= %#llx", tcp->u_lrval);
1049                                 break;
1050                         case RVAL_LOCTAL:
1051                                 tprintf("= %#llo", tcp->u_lrval);
1052                                 break;
1053                         */
1054                         case RVAL_LUDECIMAL:
1055                                 tprintf("= %llu", tcp->u_lrval);
1056                                 break;
1057                         /*
1058                         case RVAL_LDECIMAL:
1059                                 tprintf("= %lld", tcp->u_lrval);
1060                                 break;
1061                         */
1062 #endif /* HAVE_STRUCT_TCB_EXT_ARG */
1063                         default:
1064                                 error_msg("invalid rval format");
1065                                 break;
1066                         }
1067                 }
1068                 if ((sys_res & RVAL_STR) && tcp->auxstr)
1069                         tprintf(" (%s)", tcp->auxstr);
1070         }
1071         if (Tflag) {
1072                 tv_sub(&tv, &tv, &tcp->etime);
1073                 tprintf(" <%ld.%06ld>",
1074                         (long) tv.tv_sec, (long) tv.tv_usec);
1075         }
1076         tprints("\n");
1077         dumpio(tcp);
1078         line_ended();
1079
1080 #ifdef USE_LIBUNWIND
1081         if (stack_trace_enabled)
1082                 unwind_print_stacktrace(tcp);
1083 #endif
1084
1085  ret:
1086         tcp->flags &= ~TCB_INSYSCALL;
1087         tcp->sys_func_rval = 0;
1088         return 0;
1089 }
1090
1091 int
1092 trace_syscall(struct tcb *tcp)
1093 {
1094         return exiting(tcp) ?
1095                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
1096 }
1097
1098 bool
1099 is_erestart(struct tcb *tcp)
1100 {
1101         switch (tcp->u_error) {
1102                 case ERESTARTSYS:
1103                 case ERESTARTNOINTR:
1104                 case ERESTARTNOHAND:
1105                 case ERESTART_RESTARTBLOCK:
1106                         return true;
1107                 default:
1108                         return false;
1109         }
1110 }
1111
1112 static int saved_u_error;
1113
1114 void
1115 temporarily_clear_syserror(struct tcb *tcp)
1116 {
1117         saved_u_error = tcp->u_error;
1118         tcp->u_error = 0;
1119 }
1120
1121 void
1122 restore_cleared_syserror(struct tcb *tcp)
1123 {
1124         tcp->u_error = saved_u_error;
1125 }
1126
1127 #include "kernel_types.h"
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 #if defined ARCH_PC_REG
1169 # define ARCH_GET_PC 0
1170 #elif defined ARCH_PC_PEEK_ADDR
1171         long pc;
1172 # define ARCH_PC_REG pc
1173 # define ARCH_GET_PC upeek(tcp->pid, ARCH_PC_PEEK_ADDR, &pc)
1174 #else
1175 # error Neither ARCH_PC_REG nor ARCH_PC_PEEK_ADDR is defined
1176 #endif
1177         if (get_regs_error || ARCH_GET_PC)
1178                 tprints(current_wordsize == 4 ? "[????????] "
1179                                               : "[????????????????] ");
1180         else
1181                 tprintf(current_wordsize == 4 ? "[%08lx] " : "[%016lx] ",
1182                         (unsigned long) ARCH_PC_REG);
1183 }
1184
1185 #if defined ARCH_REGS_FOR_GETREGSET
1186 static long
1187 get_regset(pid_t pid)
1188 {
1189 # ifdef ARCH_IOVEC_FOR_GETREGSET
1190         /* variable iovec */
1191         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1192         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1193                       &ARCH_IOVEC_FOR_GETREGSET);
1194 # else
1195         /* constant iovec */
1196         static struct iovec io = {
1197                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1198                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1199         };
1200         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1201
1202 # endif
1203 }
1204 #endif /* ARCH_REGS_FOR_GETREGSET */
1205
1206 void
1207 get_regs(pid_t pid)
1208 {
1209 #undef USE_GET_SYSCALL_RESULT_REGS
1210 #ifdef ARCH_REGS_FOR_GETREGSET
1211 # ifdef X86_64
1212         /* Try PTRACE_GETREGSET first, fallback to PTRACE_GETREGS. */
1213         static int getregset_support;
1214
1215         if (getregset_support >= 0) {
1216                 get_regs_error = get_regset(pid);
1217                 if (getregset_support > 0)
1218                         return;
1219                 if (get_regs_error >= 0) {
1220                         getregset_support = 1;
1221                         return;
1222                 }
1223                 if (errno == EPERM || errno == ESRCH)
1224                         return;
1225                 getregset_support = -1;
1226         }
1227         get_regs_error = getregs_old(pid);
1228 # else /* !X86_64 */
1229         /* Assume that PTRACE_GETREGSET works. */
1230         get_regs_error = get_regset(pid);
1231 # endif
1232 #elif defined ARCH_REGS_FOR_GETREGS
1233 # if defined SPARC || defined SPARC64
1234         /* SPARC systems have the meaning of data and addr reversed */
1235         get_regs_error = ptrace(PTRACE_GETREGS, pid, (char *)&ARCH_REGS_FOR_GETREGS, 0);
1236 # elif defined POWERPC
1237         static bool old_kernel = 0;
1238         if (old_kernel)
1239                 goto old;
1240         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1241         if (get_regs_error && errno == EIO) {
1242                 old_kernel = 1;
1243  old:
1244                 get_regs_error = getregs_old(pid);
1245         }
1246 # else
1247         /* Assume that PTRACE_GETREGS works. */
1248         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1249 # endif
1250
1251 #else /* !ARCH_REGS_FOR_GETREGSET && !ARCH_REGS_FOR_GETREGS */
1252 # define USE_GET_SYSCALL_RESULT_REGS 1
1253 # warning get_regs is not implemented for this architecture yet
1254         get_regs_error = 0;
1255 #endif
1256 }
1257
1258 /*
1259  * Returns:
1260  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1261  * 1: ok, continue in trace_syscall_entering().
1262  * other: error, trace_syscall_entering() should print error indicator
1263  *    ("????" etc) and bail out.
1264  */
1265 int
1266 get_scno(struct tcb *tcp)
1267 {
1268         if (get_regs_error)
1269                 return -1;
1270
1271         int rc = arch_get_scno(tcp);
1272         if (rc != 1)
1273                 return rc;
1274
1275         if (SCNO_IS_VALID(tcp->scno)) {
1276                 tcp->s_ent = &sysent[tcp->scno];
1277                 tcp->qual_flg = qual_flags[tcp->scno];
1278         } else {
1279                 static const struct_sysent unknown = {
1280                         .nargs = MAX_ARGS,
1281                         .sys_flags = 0,
1282                         .sys_func = printargs,
1283                         .sys_name = "system call",
1284                 };
1285                 tcp->s_ent = &unknown;
1286                 tcp->qual_flg = QUAL_RAW | DEFAULT_QUAL_FLAGS;
1287                 if (debug_flag)
1288                         error_msg("pid %d invalid syscall %ld", tcp->pid, tcp->scno);
1289         }
1290         return 1;
1291 }
1292
1293 #ifdef USE_GET_SYSCALL_RESULT_REGS
1294 static int get_syscall_result_regs(struct tcb *);
1295 #endif
1296
1297 /* Returns:
1298  * 1: ok, continue in trace_syscall_exiting().
1299  * -1: error, trace_syscall_exiting() should print error indicator
1300  *    ("????" etc) and bail out.
1301  */
1302 static int
1303 get_syscall_result(struct tcb *tcp)
1304 {
1305 #ifdef USE_GET_SYSCALL_RESULT_REGS
1306         if (get_syscall_result_regs(tcp))
1307                 return -1;
1308 #endif
1309         tcp->u_error = 0;
1310         get_error(tcp, !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS));
1311
1312         return 1;
1313 }
1314
1315 #include "get_scno.c"
1316 #include "get_syscall_args.c"
1317 #ifdef USE_GET_SYSCALL_RESULT_REGS
1318 # include "get_syscall_result.c"
1319 #endif
1320 #include "get_error.c"
1321 #if defined X86_64 || defined POWERPC
1322 # include "getregs_old.c"
1323 #endif