1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  * Copyright 2012, Josef 'Jeff' Sipek <jeffpc@31bits.net>. All rights reserved.
  25  */
  26 
  27 #include <sys/types.h>
  28 #include <sys/mman.h>
  29 #include <sys/priocntl.h>
  30 #include <sys/rtpriocntl.h>
  31 #include <sys/resource.h>
  32 #include <sys/termios.h>
  33 #include <sys/param.h>
  34 #include <sys/regset.h>
  35 #include <sys/frame.h>
  36 #include <sys/stack.h>
  37 #include <sys/reg.h>
  38 
  39 #include <libproc.h>
  40 #include <libscf.h>
  41 #include <alloca.h>
  42 #include <unistd.h>
  43 #include <string.h>
  44 #include <stdlib.h>
  45 #include <fcntl.h>
  46 #include <dlfcn.h>
  47 #include <libctf.h>
  48 #include <errno.h>
  49 #include <kvm.h>
  50 
  51 #include <mdb/mdb_lex.h>
  52 #include <mdb/mdb_debug.h>
  53 #include <mdb/mdb_signal.h>
  54 #include <mdb/mdb_string.h>
  55 #include <mdb/mdb_modapi.h>
  56 #include <mdb/mdb_target.h>
  57 #include <mdb/mdb_gelf.h>
  58 #include <mdb/mdb_conf.h>
  59 #include <mdb/mdb_err.h>
  60 #include <mdb/mdb_io_impl.h>
  61 #include <mdb/mdb_frame.h>
  62 #include <mdb/mdb_set.h>
  63 #include <kmdb/kmdb_kctl.h>
  64 #include <mdb/mdb.h>
  65 
  66 #ifndef STACK_BIAS
  67 #define STACK_BIAS      0
  68 #endif
  69 
  70 #if defined(__sparc)
  71 #define STACK_REGISTER  SP
  72 #else
  73 #define STACK_REGISTER  REG_FP
  74 #endif
  75 
  76 #ifdef _LP64
  77 #define MDB_DEF_IPATH   \
  78         "%r/usr/platform/%p/lib/adb/%i:" \
  79         "%r/usr/platform/%m/lib/adb/%i:" \
  80         "%r/usr/lib/adb/%i"
  81 #define MDB_DEF_LPATH   \
  82         "%r/usr/platform/%p/lib/mdb/%t/%i:" \
  83         "%r/usr/platform/%m/lib/mdb/%t/%i:" \
  84         "%r/usr/lib/mdb/%t/%i"
  85 #else
  86 #define MDB_DEF_IPATH   \
  87         "%r/usr/platform/%p/lib/adb:" \
  88         "%r/usr/platform/%m/lib/adb:" \
  89         "%r/usr/lib/adb"
  90 #define MDB_DEF_LPATH   \
  91         "%r/usr/platform/%p/lib/mdb/%t:" \
  92         "%r/usr/platform/%m/lib/mdb/%t:" \
  93         "%r/usr/lib/mdb/%t"
  94 #endif
  95 
  96 #define MDB_DEF_PROMPT "> "
  97 
  98 /*
  99  * Similar to the panic_* variables in the kernel, we keep some relevant
 100  * information stored in a set of global _mdb_abort_* variables; in the
 101  * event that the debugger dumps core, these will aid core dump analysis.
 102  */
 103 const char *volatile _mdb_abort_str;    /* reason for failure */
 104 siginfo_t _mdb_abort_info;              /* signal info for fatal signal */
 105 ucontext_t _mdb_abort_ctx;              /* context fatal signal interrupted */
 106 int _mdb_abort_rcount;                  /* number of times resume requested */
 107 int _mdb_self_fd = -1;                  /* fd for self as for valid_frame */
 108 
 109 static void
 110 terminate(int status)
 111 {
 112         (void) mdb_signal_blockall();
 113         mdb_destroy();
 114         exit(status);
 115 }
 116 
 117 static void
 118 print_frame(uintptr_t pc, int fnum)
 119 {
 120         Dl_info dli;
 121 
 122         if (dladdr((void *)pc, &dli)) {
 123                 mdb_iob_printf(mdb.m_err, "    [%d] %s`%s+0x%lx()\n", fnum,
 124                     strbasename(dli.dli_fname), dli.dli_sname,
 125                     pc - (uintptr_t)dli.dli_saddr);
 126         } else
 127                 mdb_iob_printf(mdb.m_err, "    [%d] %p()\n", fnum, pc);
 128 }
 129 
 130 static int
 131 valid_frame(struct frame *fr)
 132 {
 133         static struct frame fake;
 134         uintptr_t addr = (uintptr_t)fr;
 135 
 136         if (pread(_mdb_self_fd, &fake, sizeof (fake), addr) != sizeof (fake)) {
 137                 mdb_iob_printf(mdb.m_err, "    invalid frame (%p)\n", fr);
 138                 return (0);
 139         }
 140 
 141         if (addr & (STACK_ALIGN - 1)) {
 142                 mdb_iob_printf(mdb.m_err, "    mis-aligned frame (%p)\n", fr);
 143                 return (0);
 144         }
 145 
 146         return (1);
 147 }
 148 
 149 /*ARGSUSED*/
 150 static void
 151 flt_handler(int sig, siginfo_t *sip, ucontext_t *ucp, void *data)
 152 {
 153         static const struct rlimit rl = {
 154                 (rlim_t)RLIM_INFINITY, (rlim_t)RLIM_INFINITY
 155         };
 156 
 157         const mdb_idcmd_t *idcp = NULL;
 158 
 159         if (mdb.m_frame != NULL && mdb.m_frame->f_cp != NULL)
 160                 idcp = mdb.m_frame->f_cp->c_dcmd;
 161 
 162         if (sip != NULL)
 163                 bcopy(sip, &_mdb_abort_info, sizeof (_mdb_abort_info));
 164         if (ucp != NULL)
 165                 bcopy(ucp, &_mdb_abort_ctx, sizeof (_mdb_abort_ctx));
 166 
 167         _mdb_abort_info.si_signo = sig;
 168         (void) mdb_signal_sethandler(sig, SIG_DFL, NULL);
 169 
 170         /*
 171          * If there is no current dcmd, or the current dcmd comes from a
 172          * builtin module, we don't allow resume and always core dump.
 173          */
 174         if (idcp == NULL || idcp->idc_modp == NULL ||
 175             idcp->idc_modp == &mdb.m_rmod || idcp->idc_modp->mod_hdl == NULL)
 176                 goto dump;
 177 
 178         if (mdb.m_term != NULL) {
 179                 struct frame *fr = (struct frame *)
 180                     (ucp->uc_mcontext.gregs[STACK_REGISTER] + STACK_BIAS);
 181 
 182                 char signame[SIG2STR_MAX];
 183                 int i = 1;
 184                 char c;
 185 
 186                 if (sig2str(sig, signame) == -1) {
 187                         mdb_iob_printf(mdb.m_err,
 188                             "\n*** %s: received signal %d at:\n",
 189                             mdb.m_pname, sig);
 190                 } else {
 191                         mdb_iob_printf(mdb.m_err,
 192                             "\n*** %s: received signal %s at:\n",
 193                             mdb.m_pname, signame);
 194                 }
 195 
 196                 if (ucp->uc_mcontext.gregs[REG_PC] != 0)
 197                         print_frame(ucp->uc_mcontext.gregs[REG_PC], i++);
 198 
 199                 while (fr != NULL && valid_frame(fr) && fr->fr_savpc != 0) {
 200                         print_frame(fr->fr_savpc, i++);
 201                         fr = (struct frame *)
 202                             ((uintptr_t)fr->fr_savfp + STACK_BIAS);
 203                 }
 204 
 205 query:
 206                 mdb_iob_printf(mdb.m_err, "\n%s: (c)ore dump, (q)uit, "
 207                     "(r)ecover, or (s)top for debugger [cqrs]? ", mdb.m_pname);
 208 
 209                 mdb_iob_flush(mdb.m_err);
 210 
 211                 for (;;) {
 212                         if (IOP_READ(mdb.m_term, &c, sizeof (c)) != sizeof (c))
 213                                 goto dump;
 214 
 215                         switch (c) {
 216                         case 'c':
 217                         case 'C':
 218                                 (void) setrlimit(RLIMIT_CORE, &rl);
 219                                 mdb_iob_printf(mdb.m_err, "\n%s: attempting "
 220                                     "to dump core ...\n", mdb.m_pname);
 221                                 goto dump;
 222 
 223                         case 'q':
 224                         case 'Q':
 225                                 mdb_iob_discard(mdb.m_out);
 226                                 mdb_iob_nl(mdb.m_err);
 227                                 (void) mdb_signal_unblockall();
 228                                 terminate(1);
 229                                 /*NOTREACHED*/
 230 
 231                         case 'r':
 232                         case 'R':
 233                                 mdb_iob_printf(mdb.m_err, "\n%s: unloading "
 234                                     "module '%s' ...\n", mdb.m_pname,
 235                                     idcp->idc_modp->mod_name);
 236 
 237                                 (void) mdb_module_unload(
 238                                     idcp->idc_modp->mod_name, 0);
 239 
 240                                 (void) mdb_signal_sethandler(sig,
 241                                     flt_handler, NULL);
 242 
 243                                 _mdb_abort_rcount++;
 244                                 mdb.m_intr = 0;
 245                                 mdb.m_pend = 0;
 246 
 247                                 (void) mdb_signal_unblockall();
 248                                 longjmp(mdb.m_frame->f_pcb, MDB_ERR_ABORT);
 249                                 /*NOTREACHED*/
 250 
 251                         case 's':
 252                         case 'S':
 253                                 mdb_iob_printf(mdb.m_err, "\n%s: "
 254                                     "attempting to stop pid %d ...\n",
 255                                     mdb.m_pname, (int)getpid());
 256 
 257                                 /*
 258                                  * Stop ourself; if this fails or we are
 259                                  * subsequently continued, ask again.
 260                                  */
 261                                 (void) mdb_signal_raise(SIGSTOP);
 262                                 (void) mdb_signal_unblockall();
 263                                 goto query;
 264                         }
 265                 }
 266         }
 267 
 268 dump:
 269         if (SI_FROMUSER(sip)) {
 270                 (void) mdb_signal_block(sig);
 271                 (void) mdb_signal_raise(sig);
 272         }
 273 
 274         (void) sigfillset(&ucp->uc_sigmask);
 275         (void) sigdelset(&ucp->uc_sigmask, sig);
 276 
 277         if (_mdb_abort_str == NULL)
 278                 _mdb_abort_str = "fatal signal received";
 279 
 280         ucp->uc_flags |= UC_SIGMASK;
 281         (void) setcontext(ucp);
 282 }
 283 
 284 /*ARGSUSED*/
 285 static void
 286 int_handler(int sig, siginfo_t *sip, ucontext_t *ucp, void *data)
 287 {
 288         if (mdb.m_intr == 0)
 289                 longjmp(mdb.m_frame->f_pcb, MDB_ERR_SIGINT);
 290         else
 291                 mdb.m_pend++;
 292 }
 293 
 294 static void
 295 control_kmdb(int start)
 296 {
 297         int fd;
 298 
 299         if ((fd = open("/dev/kmdb", O_RDONLY)) < 0)
 300                 die("failed to open /dev/kmdb");
 301 
 302         if (start) {
 303                 char *state = mdb_get_config();
 304 
 305                 if (ioctl(fd, KMDB_IOC_START, state) < 0)
 306                         die("failed to start kmdb");
 307 
 308                 strfree(state);
 309         } else {
 310                 if (ioctl(fd, KMDB_IOC_STOP) < 0)
 311                         die("failed to stop kmdb");
 312         }
 313 
 314         (void) close(fd);
 315 }
 316 
 317 static void
 318 usage(int status)
 319 {
 320         mdb_iob_printf(mdb.m_err, "Usage: %s [-fkmuwyAFKMSUW] [+/-o option] "
 321             "[-p pid] [-s dist] [-I path] [-L path]\n\t[-P prompt] "
 322             "[-R root] [-V dis-version] [object [core] | core | suffix]\n\n",
 323             mdb.m_pname);
 324 
 325         mdb_iob_puts(mdb.m_err,
 326             "\t-f force raw file debugging mode\n"
 327             "\t-k force kernel debugging mode\n"
 328             "\t-m disable demand-loading of module symbols\n"
 329             "\t-o set specified debugger option (+o to unset)\n"
 330             "\t-p attach to specified process-id\n"
 331             "\t-s set symbol matching distance\n"
 332             "\t-u force user program debugging mode\n"
 333             "\t-w enable write mode\n"
 334             "\t-y send terminal initialization sequences for tty mode\n"
 335             "\t-A disable automatic loading of mdb modules\n"
 336             "\t-F enable forcible takeover mode\n"
 337             "\t-K stop operating system and enter live kernel debugger\n"
 338             "\t-M preload all module symbols\n"
 339             "\t-I set initial path for macro files\n"
 340             "\t-L set initial path for module libs\n"
 341             "\t-P set command-line prompt\n"
 342             "\t-R set root directory for pathname expansion\n"
 343             "\t-S suppress processing of ~/.mdbrc file\n"
 344             "\t-U unload live kernel debugger\n"
 345             "\t-W enable I/O-mapped memory access (kernel only)\n"
 346             "\t-V set disassembler version\n");
 347 
 348         terminate(status);
 349 }
 350 
 351 static char *
 352 mdb_scf_console_term(void)
 353 {
 354         scf_simple_prop_t *prop;
 355         char *term = NULL;
 356 
 357         if ((prop = scf_simple_prop_get(NULL,
 358             "svc:/system/console-login:default", "ttymon",
 359             "terminal_type")) == NULL)
 360                 return (NULL);
 361 
 362         if (scf_simple_prop_type(prop) == SCF_TYPE_ASTRING &&
 363             (term = scf_simple_prop_next_astring(prop)) != NULL)
 364                 term = strdup(term);
 365 
 366         scf_simple_prop_free(prop);
 367         return (term);
 368 }
 369 
 370 /*
 371  * Unpleasant hack: we might be debugging a hypervisor domain dump.
 372  * Earlier versions use a non-ELF file.  Later versions are ELF, but are
 373  * /always/ ELF64, so our standard ehdr check isn't good enough.  Since
 374  * we don't want to know too much about the file format, we'll ask
 375  * mdb_kb.
 376  */
 377 #ifdef __x86
 378 static int
 379 identify_xvm_file(const char *file, int *longmode)
 380 {
 381         int (*identify)(const char *, int *);
 382 
 383         if (mdb_module_load("mdb_kb", MDB_MOD_GLOBAL | MDB_MOD_SILENT) != 0)
 384                 return (0);
 385 
 386         identify = (int (*)())dlsym(RTLD_NEXT, "xkb_identify");
 387 
 388         if (identify == NULL)
 389                 return (0);
 390 
 391         return (identify(file, longmode));
 392 }
 393 #else
 394 /*ARGSUSED*/
 395 static int
 396 identify_xvm_file(const char *file, int *longmode)
 397 {
 398         return (0);
 399 }
 400 #endif /* __x86 */
 401 
 402 int
 403 main(int argc, char *argv[], char *envp[])
 404 {
 405         extern int mdb_kvm_is_compressed_dump(mdb_io_t *);
 406         mdb_tgt_ctor_f *tgt_ctor = NULL;
 407         const char **tgt_argv = alloca(argc * sizeof (char *));
 408         int tgt_argc = 0;
 409         mdb_tgt_t *tgt;
 410 
 411         char object[MAXPATHLEN], execname[MAXPATHLEN];
 412         mdb_io_t *in_io, *out_io, *err_io, *null_io;
 413         struct termios tios;
 414         int status, c;
 415         char *p;
 416 
 417         const char *Iflag = NULL, *Lflag = NULL, *Vflag = NULL, *pidarg = NULL;
 418         int fflag = 0, Kflag = 0, Rflag = 0, Sflag = 0, Oflag = 0, Uflag = 0;
 419 
 420         int ttylike;
 421         int longmode = 0;
 422 
 423         stack_t sigstack;
 424 
 425         if (realpath(getexecname(), execname) == NULL) {
 426                 (void) strncpy(execname, argv[0], MAXPATHLEN);
 427                 execname[MAXPATHLEN - 1] = '\0';
 428         }
 429 
 430         mdb_create(execname, argv[0]);
 431         bzero(tgt_argv, argc * sizeof (char *));
 432         argv[0] = (char *)mdb.m_pname;
 433         _mdb_self_fd = open("/proc/self/as", O_RDONLY);
 434 
 435         mdb.m_env = envp;
 436 
 437         out_io = mdb_fdio_create(STDOUT_FILENO);
 438         mdb.m_out = mdb_iob_create(out_io, MDB_IOB_WRONLY);
 439 
 440         err_io = mdb_fdio_create(STDERR_FILENO);
 441         mdb.m_err = mdb_iob_create(err_io, MDB_IOB_WRONLY);
 442         mdb_iob_clrflags(mdb.m_err, MDB_IOB_AUTOWRAP);
 443 
 444         null_io = mdb_nullio_create();
 445         mdb.m_null = mdb_iob_create(null_io, MDB_IOB_WRONLY);
 446 
 447         in_io = mdb_fdio_create(STDIN_FILENO);
 448         if ((mdb.m_termtype = getenv("TERM")) != NULL) {
 449                 mdb.m_termtype = strdup(mdb.m_termtype);
 450                 mdb.m_flags |= MDB_FL_TERMGUESS;
 451         }
 452         mdb.m_term = NULL;
 453 
 454         mdb_dmode(mdb_dstr2mode(getenv("MDB_DEBUG")));
 455         mdb.m_pgid = getpgrp();
 456 
 457         if (getenv("_MDB_EXEC") != NULL)
 458                 mdb.m_flags |= MDB_FL_EXEC;
 459 
 460         /*
 461          * Setup an alternate signal stack.  When tearing down pipelines in
 462          * terminate(), we may have to destroy the stack of the context in
 463          * which we are currently executing the signal handler.
 464          */
 465         sigstack.ss_sp = mmap(NULL, SIGSTKSZ, PROT_READ | PROT_WRITE,
 466             MAP_PRIVATE | MAP_ANON, -1, 0);
 467         if (sigstack.ss_sp == MAP_FAILED)
 468                 die("could not allocate signal stack");
 469         sigstack.ss_size = SIGSTKSZ;
 470         sigstack.ss_flags = 0;
 471         if (sigaltstack(&sigstack, NULL) != 0)
 472                 die("could not set signal stack");
 473 
 474         (void) mdb_signal_sethandler(SIGPIPE, SIG_IGN, NULL);
 475         (void) mdb_signal_sethandler(SIGQUIT, SIG_IGN, NULL);
 476 
 477         (void) mdb_signal_sethandler(SIGILL, flt_handler, NULL);
 478         (void) mdb_signal_sethandler(SIGTRAP, flt_handler, NULL);
 479         (void) mdb_signal_sethandler(SIGIOT, flt_handler, NULL);
 480         (void) mdb_signal_sethandler(SIGEMT, flt_handler, NULL);
 481         (void) mdb_signal_sethandler(SIGFPE, flt_handler, NULL);
 482         (void) mdb_signal_sethandler(SIGBUS, flt_handler, NULL);
 483         (void) mdb_signal_sethandler(SIGSEGV, flt_handler, NULL);
 484 
 485         (void) mdb_signal_sethandler(SIGHUP, (mdb_signal_f *)terminate, NULL);
 486         (void) mdb_signal_sethandler(SIGTERM, (mdb_signal_f *)terminate, NULL);
 487 
 488         for (mdb.m_rdvers = RD_VERSION; mdb.m_rdvers > 0; mdb.m_rdvers--) {
 489                 if (rd_init(mdb.m_rdvers) == RD_OK)
 490                         break;
 491         }
 492 
 493         for (mdb.m_ctfvers = CTF_VERSION; mdb.m_ctfvers > 0; mdb.m_ctfvers--) {
 494                 if (ctf_version(mdb.m_ctfvers) != -1)
 495                         break;
 496         }
 497 
 498         if ((p = getenv("HISTSIZE")) != NULL && strisnum(p)) {
 499                 mdb.m_histlen = strtoi(p);
 500                 if (mdb.m_histlen < 1)
 501                         mdb.m_histlen = 1;
 502         }
 503 
 504         while (optind < argc) {
 505                 while ((c = getopt(argc, argv,
 506                     "fkmo:p:s:uwyACD:FI:KL:MOP:R:SUV:W")) != (int)EOF) {
 507                         switch (c) {
 508                         case 'f':
 509                                 fflag++;
 510                                 tgt_ctor = mdb_rawfile_tgt_create;
 511                                 break;
 512                         case 'k':
 513                                 tgt_ctor = mdb_kvm_tgt_create;
 514                                 break;
 515                         case 'm':
 516                                 mdb.m_tgtflags |= MDB_TGT_F_NOLOAD;
 517                                 mdb.m_tgtflags &= ~MDB_TGT_F_PRELOAD;
 518                                 break;
 519                         case 'o':
 520                                 if (!mdb_set_options(optarg, TRUE))
 521                                         terminate(2);
 522                                 break;
 523                         case 'p':
 524                                 tgt_ctor = mdb_proc_tgt_create;
 525                                 pidarg = optarg;
 526                                 break;
 527                         case 's':
 528                                 if (!strisnum(optarg)) {
 529                                         warn("expected integer following -s\n");
 530                                         terminate(2);
 531                                 }
 532                                 mdb.m_symdist = (size_t)(uint_t)strtoi(optarg);
 533                                 break;
 534                         case 'u':
 535                                 tgt_ctor = mdb_proc_tgt_create;
 536                                 break;
 537                         case 'w':
 538                                 mdb.m_tgtflags |= MDB_TGT_F_RDWR;
 539                                 break;
 540                         case 'y':
 541                                 mdb.m_flags |= MDB_FL_USECUP;
 542                                 break;
 543                         case 'A':
 544                                 (void) mdb_set_options("nomods", TRUE);
 545                                 break;
 546                         case 'C':
 547                                 (void) mdb_set_options("noctf", TRUE);
 548                                 break;
 549                         case 'D':
 550                                 mdb_dmode(mdb_dstr2mode(optarg));
 551                                 break;
 552                         case 'F':
 553                                 mdb.m_tgtflags |= MDB_TGT_F_FORCE;
 554                                 break;
 555                         case 'I':
 556                                 Iflag = optarg;
 557                                 break;
 558                         case 'L':
 559                                 Lflag = optarg;
 560                                 break;
 561                         case 'K':
 562                                 Kflag++;
 563                                 break;
 564                         case 'M':
 565                                 mdb.m_tgtflags |= MDB_TGT_F_PRELOAD;
 566                                 mdb.m_tgtflags &= ~MDB_TGT_F_NOLOAD;
 567                                 break;
 568                         case 'O':
 569                                 Oflag++;
 570                                 break;
 571                         case 'P':
 572                                 if (!mdb_set_prompt(optarg))
 573                                         terminate(2);
 574                                 break;
 575                         case 'R':
 576                                 (void) strncpy(mdb.m_root, optarg, MAXPATHLEN);
 577                                 mdb.m_root[MAXPATHLEN - 1] = '\0';
 578                                 Rflag++;
 579                                 break;
 580                         case 'S':
 581                                 Sflag++;
 582                                 break;
 583                         case 'U':
 584                                 Uflag++;
 585                                 break;
 586                         case 'V':
 587                                 Vflag = optarg;
 588                                 break;
 589                         case 'W':
 590                                 mdb.m_tgtflags |= MDB_TGT_F_ALLOWIO;
 591                                 break;
 592                         case '?':
 593                                 if (optopt == '?')
 594                                         usage(0);
 595                                 /* FALLTHROUGH */
 596                         default:
 597                                 usage(2);
 598                         }
 599                 }
 600 
 601                 if (optind < argc) {
 602                         const char *arg = argv[optind++];
 603 
 604                         if (arg[0] == '+' && strlen(arg) == 2) {
 605                                 if (arg[1] != 'o') {
 606                                         warn("illegal option -- %s\n", arg);
 607                                         terminate(2);
 608                                 }
 609                                 if (optind >= argc) {
 610                                         warn("option requires an argument -- "
 611                                             "%s\n", arg);
 612                                         terminate(2);
 613                                 }
 614                                 if (!mdb_set_options(argv[optind++], FALSE))
 615                                         terminate(2);
 616                         } else
 617                                 tgt_argv[tgt_argc++] = arg;
 618                 }
 619         }
 620 
 621         if (rd_ctl(RD_CTL_SET_HELPPATH, (void *)mdb.m_root) != RD_OK) {
 622                 warn("cannot set librtld_db helper path to %s\n", mdb.m_root);
 623                 terminate(2);
 624         }
 625 
 626         if (mdb.m_debug & MDB_DBG_HELP)
 627                 terminate(0); /* Quit here if we've printed out the tokens */
 628 
 629 
 630         if (Iflag != NULL && strchr(Iflag, ';') != NULL) {
 631                 warn("macro path cannot contain semicolons\n");
 632                 terminate(2);
 633         }
 634 
 635         if (Lflag != NULL && strchr(Lflag, ';') != NULL) {
 636                 warn("module path cannot contain semicolons\n");
 637                 terminate(2);
 638         }
 639 
 640         if (Kflag || Uflag) {
 641                 char *nm;
 642 
 643                 if (tgt_ctor != NULL || Iflag != NULL) {
 644                         warn("neither -f, -k, -p, -u, nor -I "
 645                             "may be used with -K\n");
 646                         usage(2);
 647                 }
 648 
 649                 if (Lflag != NULL)
 650                         mdb_set_lpath(Lflag);
 651 
 652                 if ((nm = ttyname(STDIN_FILENO)) == NULL ||
 653                     strcmp(nm, "/dev/console") != 0) {
 654                         /*
 655                          * Due to the consequences of typing mdb -K instead of
 656                          * mdb -k on a tty other than /dev/console, we require
 657                          * -F when starting kmdb from a tty other than
 658                          * /dev/console.
 659                          */
 660                         if (!(mdb.m_tgtflags & MDB_TGT_F_FORCE)) {
 661                                 die("-F must also be supplied to start kmdb "
 662                                     "from non-console tty\n");
 663                         }
 664 
 665                         if (mdb.m_termtype == NULL || (mdb.m_flags &
 666                             MDB_FL_TERMGUESS)) {
 667                                 if (mdb.m_termtype != NULL)
 668                                         strfree(mdb.m_termtype);
 669 
 670                                 if ((mdb.m_termtype = mdb_scf_console_term()) !=
 671                                     NULL)
 672                                         mdb.m_flags |= MDB_FL_TERMGUESS;
 673                         }
 674                 } else {
 675                         /*
 676                          * When on console, $TERM (if set) takes precedence over
 677                          * the SMF setting.
 678                          */
 679                         if (mdb.m_termtype == NULL && (mdb.m_termtype =
 680                             mdb_scf_console_term()) != NULL)
 681                                 mdb.m_flags |= MDB_FL_TERMGUESS;
 682                 }
 683 
 684                 control_kmdb(Kflag);
 685                 terminate(0);
 686                 /*NOTREACHED*/
 687         }
 688 
 689         /*
 690          * If standard input appears to have tty attributes, attempt to
 691          * initialize a terminal i/o backend on top of stdin and stdout.
 692          */
 693         ttylike = (IOP_CTL(in_io, TCGETS, &tios) == 0);
 694         if (ttylike) {
 695                 if ((mdb.m_term = mdb_termio_create(mdb.m_termtype,
 696                     in_io, out_io)) == NULL) {
 697                         if (!(mdb.m_flags & MDB_FL_EXEC)) {
 698                                 warn("term init failed: command-line editing "
 699                                     "and prompt will not be available\n");
 700                         }
 701                 } else {
 702                         in_io = mdb.m_term;
 703                 }
 704         }
 705 
 706         mdb.m_in = mdb_iob_create(in_io, MDB_IOB_RDONLY);
 707         if (mdb.m_term != NULL) {
 708                 mdb_iob_setpager(mdb.m_out, mdb.m_term);
 709                 if (mdb.m_flags & MDB_FL_PAGER)
 710                         mdb_iob_setflags(mdb.m_out, MDB_IOB_PGENABLE);
 711                 else
 712                         mdb_iob_clrflags(mdb.m_out, MDB_IOB_PGENABLE);
 713         } else if (ttylike)
 714                 mdb_iob_setflags(mdb.m_in, MDB_IOB_TTYLIKE);
 715         else
 716                 mdb_iob_setbuf(mdb.m_in, mdb_alloc(1, UM_SLEEP), 1);
 717 
 718         mdb_pservice_init();
 719         mdb_lex_reset();
 720 
 721         if ((mdb.m_shell = getenv("SHELL")) == NULL)
 722                 mdb.m_shell = "/bin/sh";
 723 
 724         /*
 725          * If the debugger state is to be inherited from a previous instance,
 726          * restore it now prior to path evaluation so that %R is updated.
 727          */
 728         if ((p = getenv(MDB_CONFIG_ENV_VAR)) != NULL) {
 729                 mdb_set_config(p);
 730                 (void) unsetenv(MDB_CONFIG_ENV_VAR);
 731         }
 732 
 733         /*
 734          * Path evaluation part 1: Create the initial module path to allow
 735          * the target constructor to load a support module.  Then expand
 736          * any command-line arguments that modify the paths.
 737          */
 738         if (Iflag != NULL)
 739                 mdb_set_ipath(Iflag);
 740         else
 741                 mdb_set_ipath(MDB_DEF_IPATH);
 742 
 743         if (Lflag != NULL)
 744                 mdb_set_lpath(Lflag);
 745         else
 746                 mdb_set_lpath(MDB_DEF_LPATH);
 747 
 748         if (mdb_get_prompt() == NULL && !(mdb.m_flags & MDB_FL_ADB))
 749                 (void) mdb_set_prompt(MDB_DEF_PROMPT);
 750 
 751         if (tgt_ctor == mdb_kvm_tgt_create) {
 752                 if (pidarg != NULL) {
 753                         warn("-p and -k options are mutually exclusive\n");
 754                         terminate(2);
 755                 }
 756 
 757                 if (tgt_argc == 0)
 758                         tgt_argv[tgt_argc++] = "/dev/ksyms";
 759                 if (tgt_argc == 1 && strisnum(tgt_argv[0]) == 0) {
 760                         if (mdb.m_tgtflags & MDB_TGT_F_ALLOWIO)
 761                                 tgt_argv[tgt_argc++] = "/dev/allkmem";
 762                         else
 763                                 tgt_argv[tgt_argc++] = "/dev/kmem";
 764                 }
 765         }
 766 
 767         if (pidarg != NULL) {
 768                 if (tgt_argc != 0) {
 769                         warn("-p may not be used with other arguments\n");
 770                         terminate(2);
 771                 }
 772                 if (proc_arg_psinfo(pidarg, PR_ARG_PIDS, NULL, &status) == -1) {
 773                         die("cannot attach to %s: %s\n",
 774                             pidarg, Pgrab_error(status));
 775                 }
 776                 if (strchr(pidarg, '/') != NULL)
 777                         (void) mdb_iob_snprintf(object, MAXPATHLEN,
 778                             "%s/object/a.out", pidarg);
 779                 else
 780                         (void) mdb_iob_snprintf(object, MAXPATHLEN,
 781                             "/proc/%s/object/a.out", pidarg);
 782                 tgt_argv[tgt_argc++] = object;
 783                 tgt_argv[tgt_argc++] = pidarg;
 784         }
 785 
 786         /*
 787          * Find the first argument that is not a special "-" token.  If one is
 788          * found, we will examine this file and make some inferences below.
 789          */
 790         for (c = 0; c < tgt_argc && strcmp(tgt_argv[c], "-") == 0; c++)
 791                 continue;
 792 
 793         if (c < tgt_argc) {
 794                 Elf32_Ehdr ehdr;
 795                 mdb_io_t *io;
 796 
 797                 /*
 798                  * If special "-" tokens preceded an argument, shift the entire
 799                  * argument list to the left to remove the leading "-" args.
 800                  */
 801                 if (c > 0) {
 802                         bcopy(&tgt_argv[c], tgt_argv,
 803                             sizeof (const char *) * (tgt_argc - c));
 804                         tgt_argc -= c;
 805                 }
 806 
 807                 if (fflag)
 808                         goto tcreate; /* skip re-exec and just create target */
 809 
 810                 /*
 811                  * If we just have an object file name, and that file doesn't
 812                  * exist, and it's a string of digits, infer it to be a
 813                  * sequence number referring to a pair of crash dump files.
 814                  */
 815                 if (tgt_argc == 1 && access(tgt_argv[0], F_OK) == -1 &&
 816                     strisnum(tgt_argv[0])) {
 817 
 818                         size_t len = strlen(tgt_argv[0]) + 8;
 819                         const char *object = tgt_argv[0];
 820 
 821                         tgt_argv[0] = mdb_alloc(len, UM_SLEEP);
 822                         tgt_argv[1] = mdb_alloc(len, UM_SLEEP);
 823 
 824                         (void) strcpy((char *)tgt_argv[0], "unix.");
 825                         (void) strcat((char *)tgt_argv[0], object);
 826                         (void) strcpy((char *)tgt_argv[1], "vmcore.");
 827                         (void) strcat((char *)tgt_argv[1], object);
 828 
 829                         if (access(tgt_argv[0], F_OK) == -1 &&
 830                             access(tgt_argv[1], F_OK) == -1) {
 831                                 (void) strcpy((char *)tgt_argv[1], "vmdump.");
 832                                 (void) strcat((char *)tgt_argv[1], object);
 833                                 if (access(tgt_argv[1], F_OK) == 0) {
 834                                         mdb_iob_printf(mdb.m_err,
 835                                             "cannot open compressed dump; "
 836                                             "decompress using savecore -f %s\n",
 837                                             tgt_argv[1]);
 838                                         terminate(0);
 839                                 }
 840                         }
 841 
 842                         tgt_argc = 2;
 843                 }
 844 
 845                 /*
 846                  * We need to open the object file in order to determine its
 847                  * ELF class and potentially re-exec ourself.
 848                  */
 849                 if ((io = mdb_fdio_create_path(NULL, tgt_argv[0],
 850                     O_RDONLY, 0)) == NULL)
 851                         die("failed to open %s", tgt_argv[0]);
 852 
 853                 /*
 854                  * Check for a single vmdump.N compressed dump file,
 855                  * and give a helpful message.
 856                  */
 857                 if (tgt_argc == 1) {
 858                         if (mdb_kvm_is_compressed_dump(io)) {
 859                                 mdb_iob_printf(mdb.m_err,
 860                                     "cannot open compressed dump; "
 861                                     "decompress using savecore -f %s\n",
 862                                     tgt_argv[0]);
 863                                 terminate(0);
 864                         }
 865                 }
 866 
 867                 /*
 868                  * If the target is unknown or is not the rawfile target, do
 869                  * a gelf_check to determine if the file is an ELF file.  If
 870                  * it is not and the target is unknown, use the rawfile tgt.
 871                  * Otherwise an ELF-based target is needed, so we must abort.
 872                  */
 873                 if (mdb_gelf_check(io, &ehdr, ET_NONE) == -1) {
 874                         if (tgt_ctor != NULL) {
 875                                 (void) mdb_gelf_check(io, &ehdr, ET_EXEC);
 876                                 mdb_io_destroy(io);
 877                                 terminate(1);
 878                         } else
 879                                 tgt_ctor = mdb_rawfile_tgt_create;
 880                 }
 881 
 882                 mdb_io_destroy(io);
 883 
 884                 if (identify_xvm_file(tgt_argv[0], &longmode) == 1) {
 885 #ifdef _LP64
 886                         if (!longmode)
 887                                 goto reexec;
 888 #else
 889                         if (longmode)
 890                                 goto reexec;
 891 #endif
 892                         tgt_ctor = mdb_kvm_tgt_create;
 893                         goto tcreate;
 894                 }
 895 
 896                 /*
 897                  * The object file turned out to be a user core file (ET_CORE),
 898                  * and no other arguments were specified, swap 0 and 1.  The
 899                  * proc target will infer the executable for us.
 900                  */
 901                 if (ehdr.e_type == ET_CORE) {
 902                         tgt_argv[tgt_argc++] = tgt_argv[0];
 903                         tgt_argv[0] = NULL;
 904                         tgt_ctor = mdb_proc_tgt_create;
 905                 }
 906 
 907                 /*
 908                  * If tgt_argv[1] is filled in, open it up and determine if it
 909                  * is a vmcore file.  If it is, gelf_check will fail and we
 910                  * set tgt_ctor to 'kvm'; otherwise we use the default.
 911                  */
 912                 if (tgt_argc > 1 && strcmp(tgt_argv[1], "-") != 0 &&
 913                     tgt_argv[0] != NULL && pidarg == NULL) {
 914                         Elf32_Ehdr chdr;
 915 
 916                         if (access(tgt_argv[1], F_OK) == -1)
 917                                 die("failed to access %s", tgt_argv[1]);
 918 
 919                         /* *.N case: drop vmdump.N from the list */
 920                         if (tgt_argc == 3) {
 921                                 if ((io = mdb_fdio_create_path(NULL,
 922                                     tgt_argv[2], O_RDONLY, 0)) == NULL)
 923                                         die("failed to open %s", tgt_argv[2]);
 924                                 if (mdb_kvm_is_compressed_dump(io))
 925                                         tgt_argv[--tgt_argc] = NULL;
 926                                 mdb_io_destroy(io);
 927                         }
 928 
 929                         if ((io = mdb_fdio_create_path(NULL, tgt_argv[1],
 930                             O_RDONLY, 0)) == NULL)
 931                                 die("failed to open %s", tgt_argv[1]);
 932 
 933                         if (mdb_gelf_check(io, &chdr, ET_NONE) == -1)
 934                                 tgt_ctor = mdb_kvm_tgt_create;
 935 
 936                         mdb_io_destroy(io);
 937                 }
 938 
 939                 /*
 940                  * At this point, we've read the ELF header for either an
 941                  * object file or core into ehdr.  If the class does not match
 942                  * ours, attempt to exec the mdb of the appropriate class.
 943                  */
 944 #ifdef _LP64
 945                 if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
 946                         goto reexec;
 947 #else
 948                 if (ehdr.e_ident[EI_CLASS] == ELFCLASS64)
 949                         goto reexec;
 950 #endif
 951         }
 952 
 953 tcreate:
 954         if (tgt_ctor == NULL)
 955                 tgt_ctor = mdb_proc_tgt_create;
 956 
 957         tgt = mdb_tgt_create(tgt_ctor, mdb.m_tgtflags, tgt_argc, tgt_argv);
 958 
 959         if (tgt == NULL) {
 960                 if (errno == EINVAL)
 961                         usage(2); /* target can return EINVAL to get usage */
 962                 if (errno == EMDB_TGT)
 963                         terminate(1); /* target already printed error msg */
 964                 die("failed to initialize target");
 965         }
 966 
 967         mdb_tgt_activate(tgt);
 968 
 969         mdb_create_loadable_disasms();
 970 
 971         if (Vflag != NULL && mdb_dis_select(Vflag) == -1)
 972                 warn("invalid disassembler mode -- %s\n", Vflag);
 973 
 974 
 975         if (Rflag && mdb.m_term != NULL)
 976                 warn("Using proto area %s\n", mdb.m_root);
 977 
 978         /*
 979          * If the target was successfully constructed and -O was specified,
 980          * we now attempt to enter piggy-mode for debugging jurassic problems.
 981          */
 982         if (Oflag) {
 983                 pcinfo_t pci;
 984 
 985                 (void) strcpy(pci.pc_clname, "RT");
 986 
 987                 if (priocntl(P_LWPID, P_MYID, PC_GETCID, (caddr_t)&pci) != -1) {
 988                         pcparms_t pcp;
 989                         rtparms_t *rtp = (rtparms_t *)pcp.pc_clparms;
 990 
 991                         rtp->rt_pri = 35;
 992                         rtp->rt_tqsecs = 0;
 993                         rtp->rt_tqnsecs = RT_TQDEF;
 994 
 995                         pcp.pc_cid = pci.pc_cid;
 996 
 997                         if (priocntl(P_LWPID, P_MYID, PC_SETPARMS,
 998                             (caddr_t)&pcp) == -1) {
 999                                 warn("failed to set RT parameters");
1000                                 Oflag = 0;
1001                         }
1002                 } else {
1003                         warn("failed to get RT class id");
1004                         Oflag = 0;
1005                 }
1006 
1007                 if (mlockall(MCL_CURRENT | MCL_FUTURE) == -1) {
1008                         warn("failed to lock address space");
1009                         Oflag = 0;
1010                 }
1011 
1012                 if (Oflag)
1013                         mdb_printf("%s: oink, oink!\n", mdb.m_pname);
1014         }
1015 
1016         /*
1017          * Path evaluation part 2: Re-evaluate the path now that the target
1018          * is ready (and thus we have access to the real platform string).
1019          * Do this before reading ~/.mdbrc to allow path modifications prior
1020          * to performing module auto-loading.
1021          */
1022         mdb_set_ipath(mdb.m_ipathstr);
1023         mdb_set_lpath(mdb.m_lpathstr);
1024 
1025         if (!Sflag && (p = getenv("HOME")) != NULL) {
1026                 char rcpath[MAXPATHLEN];
1027                 mdb_io_t *rc_io;
1028                 int fd;
1029 
1030                 (void) mdb_iob_snprintf(rcpath, MAXPATHLEN, "%s/.mdbrc", p);
1031                 fd = open64(rcpath, O_RDONLY);
1032 
1033                 if (fd >= 0 && (rc_io = mdb_fdio_create_named(fd, rcpath))) {
1034                         mdb_iob_t *iob = mdb_iob_create(rc_io, MDB_IOB_RDONLY);
1035                         mdb_iob_t *old = mdb.m_in;
1036 
1037                         mdb.m_in = iob;
1038                         (void) mdb_run();
1039                         mdb.m_in = old;
1040                 }
1041         }
1042 
1043         if (!(mdb.m_flags & MDB_FL_NOMODS))
1044                 mdb_module_load_all(0);
1045 
1046         (void) mdb_signal_sethandler(SIGINT, int_handler, NULL);
1047         while ((status = mdb_run()) == MDB_ERR_ABORT ||
1048             status == MDB_ERR_OUTPUT) {
1049                 /*
1050                  * If a write failed on stdout, give up.  A more informative
1051                  * error message will already have been printed by mdb_run().
1052                  */
1053                 if (status == MDB_ERR_OUTPUT &&
1054                     mdb_iob_getflags(mdb.m_out) & MDB_IOB_ERR) {
1055                         mdb_warn("write to stdout failed, exiting\n");
1056                         break;
1057                 }
1058                 continue;
1059         }
1060 
1061         terminate((status == MDB_ERR_QUIT || status == 0) ? 0 : 1);
1062         /*NOTREACHED*/
1063         return (0);
1064 
1065 reexec:
1066         if ((p = strrchr(execname, '/')) == NULL)
1067                 die("cannot determine absolute pathname\n");
1068 #ifdef _LP64
1069 #ifdef __sparc
1070         (void) strcpy(p, "/../sparcv7/");
1071 #else
1072         (void) strcpy(p, "/../i86/");
1073 #endif
1074 #else
1075 #ifdef __sparc
1076         (void) strcpy(p, "/../sparcv9/");
1077 #else
1078         (void) strcpy(p, "/../amd64/");
1079 #endif
1080 #endif
1081         (void) strcat(p, mdb.m_pname);
1082 
1083         if (mdb.m_term != NULL)
1084                 (void) IOP_CTL(in_io, TCSETSW, &tios);
1085 
1086         (void) putenv("_MDB_EXEC=1");
1087         (void) execv(execname, argv);
1088 
1089         /*
1090          * If execv fails, suppress ENOEXEC.  Experience shows the most common
1091          * reason is that the machine is booted under a 32-bit kernel, in which
1092          * case it is clearer to only print the message below.
1093          */
1094         if (errno != ENOEXEC)
1095                 warn("failed to exec %s", execname);
1096 #ifdef _LP64
1097         die("64-bit %s cannot debug 32-bit program %s\n",
1098             mdb.m_pname, tgt_argv[0] ?
1099             tgt_argv[0] : tgt_argv[1]);
1100 #else
1101         die("32-bit %s cannot debug 64-bit program %s\n",
1102             mdb.m_pname, tgt_argv[0] ?
1103             tgt_argv[0] : tgt_argv[1]);
1104 #endif
1105 
1106         goto tcreate;
1107 }