sys/ddb/db_command.c

   1 /*-
   2  * Mach Operating System
   3  * Copyright (c) 1991,1990 Carnegie Mellon University
   4  * All Rights Reserved.
   5  *
   6  * Permission to use, copy, modify and distribute this software and its
   7  * documentation is hereby granted, provided that both the copyright
   8  * notice and this permission notice appear in all copies of the
   9  * software, derivative works or modified versions, and any portions
  10  * thereof, and that both notices appear in supporting documentation.
  11  *
  12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
  13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  15  *
  16  * Carnegie Mellon requests users of this software to return to
  17  *
  18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  19  *  School of Computer Science
  20  *  Carnegie Mellon University
  21  *  Pittsburgh PA 15213-3890
  22  *
  23  * any improvements or extensions that they make and grant Carnegie the
  24  * rights to redistribute these changes.
  25  */
  26 /*
  27  *      Author: David B. Golub, Carnegie Mellon University
  28  *      Date:   7/90
  29  */
  30 /*
  31  * Command dispatcher.
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/linker_set.h>
  39 #include <sys/lock.h>
  40 #include <sys/kdb.h>
  41 #include <sys/mutex.h>
  42 #include <sys/proc.h>
  43 #include <sys/reboot.h>
  44 #include <sys/signalvar.h>
  45 #include <sys/systm.h>
  46 #include <sys/cons.h>
  47 #include <sys/conf.h>
  48 #include <sys/watchdog.h>
  49 #include <sys/kernel.h>
  50
  51 #include <ddb/ddb.h>
  52 #include <ddb/db_command.h>
  53 #include <ddb/db_lex.h>
  54 #include <ddb/db_output.h>
  55
  56 #include <machine/cpu.h>
  57 #include <machine/setjmp.h>
  58
  59 /*
  60  * Exported global variables
  61  */
  62 int             db_cmd_loop_done;
  63 db_addr_t       db_dot;
  64 db_addr_t       db_last_addr;
  65 db_addr_t       db_prev;
  66 db_addr_t       db_next;
  67
  68 static db_cmdfcn_t      db_dump;
  69 static db_cmdfcn_t      db_fncall;
  70 static db_cmdfcn_t      db_gdb;
  71 static db_cmdfcn_t      db_halt;
  72 static db_cmdfcn_t      db_kill;
  73 static db_cmdfcn_t      db_reset;
  74 static db_cmdfcn_t      db_stack_trace;
  75 static db_cmdfcn_t      db_stack_trace_active;
  76 static db_cmdfcn_t      db_stack_trace_all;
  77 static db_cmdfcn_t      db_watchdog;
  78
  79 /*
  80  * 'show' commands
  81  */
  82
  83 static struct command db_show_active_cmds[] = {
  84         { "trace",      db_stack_trace_active,  0,      NULL },
  85 };
  86 struct command_table db_show_active_table =
  87     LIST_HEAD_INITIALIZER(db_show_active_table);
  88
  89 static struct command db_show_all_cmds[] = {
  90         { "trace",      db_stack_trace_all,     0,      NULL },
  91 };
  92 struct command_table db_show_all_table =
  93     LIST_HEAD_INITIALIZER(db_show_all_table);
  94
  95 static struct command db_show_cmds[] = {
  96         { "active",     0,                      0,      &db_show_active_table },
  97         { "all",        0,                      0,      &db_show_all_table },
  98         { "registers",  db_show_regs,           0,      NULL },
  99         { "breaks",     db_listbreak_cmd,       0,      NULL },
 100         { "threads",    db_show_threads,        0,      NULL },
 101 };
 102 struct command_table db_show_table = LIST_HEAD_INITIALIZER(db_show_table);
 103
 104 static struct command db_cmds[] = {
 105         { "print",      db_print_cmd,           0,      NULL },
 106         { "p",          db_print_cmd,           0,      NULL },
 107         { "examine",    db_examine_cmd,         CS_SET_DOT, NULL },
 108         { "x",          db_examine_cmd,         CS_SET_DOT, NULL },
 109         { "search",     db_search_cmd,          CS_OWN|CS_SET_DOT, NULL },
 110         { "set",        db_set_cmd,             CS_OWN, NULL },
 111         { "write",      db_write_cmd,           CS_MORE|CS_SET_DOT, NULL },
 112         { "w",          db_write_cmd,           CS_MORE|CS_SET_DOT, NULL },
 113         { "delete",     db_delete_cmd,          0,      NULL },
 114         { "d",          db_delete_cmd,          0,      NULL },
 115         { "dump",       db_dump,                0,      NULL },
 116         { "break",      db_breakpoint_cmd,      0,      NULL },
 117         { "b",          db_breakpoint_cmd,      0,      NULL },
 118         { "dwatch",     db_deletewatch_cmd,     0,      NULL },
 119         { "watch",      db_watchpoint_cmd,      CS_MORE,NULL },
 120         { "dhwatch",    db_deletehwatch_cmd,    0,      NULL },
 121         { "hwatch",     db_hwatchpoint_cmd,     0,      NULL },
 122         { "step",       db_single_step_cmd,     0,      NULL },
 123         { "s",          db_single_step_cmd,     0,      NULL },
 124         { "continue",   db_continue_cmd,        0,      NULL },
 125         { "c",          db_continue_cmd,        0,      NULL },
 126         { "until",      db_trace_until_call_cmd,0,      NULL },
 127         { "next",       db_trace_until_matching_cmd,0,  NULL },
 128         { "match",      db_trace_until_matching_cmd,0,  NULL },
 129         { "trace",      db_stack_trace,         CS_OWN, NULL },
 130         { "t",          db_stack_trace,         CS_OWN, NULL },
 131         /* XXX alias for active trace */
 132         { "acttrace",   db_stack_trace_active,  0,      NULL },
 133         /* XXX alias for all trace */
 134         { "alltrace",   db_stack_trace_all,     0,      NULL },
 135         { "where",      db_stack_trace,         CS_OWN, NULL },
 136         { "bt",         db_stack_trace,         CS_OWN, NULL },
 137         { "call",       db_fncall,              CS_OWN, NULL },
 138         { "show",       0,                      0,      &db_show_table },
 139         { "ps",         db_ps,                  0,      NULL },
 140         { "gdb",        db_gdb,                 0,      NULL },
 141         { "halt",       db_halt,                0,      NULL },
 142         { "reboot",     db_reset,               0,      NULL },
 143         { "reset",      db_reset,               0,      NULL },
 144         { "kill",       db_kill,                CS_OWN, NULL },
 145         { "watchdog",   db_watchdog,            CS_OWN, NULL },
 146         { "thread",     db_set_thread,          CS_OWN, NULL },
 147         { "run",        db_run_cmd,             CS_OWN, NULL },
 148         { "script",     db_script_cmd,          CS_OWN, NULL },
 149         { "scripts",    db_scripts_cmd,         0,      NULL },
 150         { "unscript",   db_unscript_cmd,        CS_OWN, NULL },
 151         { "capture",    db_capture_cmd,         CS_OWN, NULL },
 152         { "textdump",   db_textdump_cmd,        CS_OWN, NULL },
 153         { "findstack",  db_findstack_cmd,       0,      NULL },
 154 };
 155 struct command_table db_cmd_table = LIST_HEAD_INITIALIZER(db_cmd_table);
 156
 157 static struct command   *db_last_command = NULL;
 158
 159 /*
 160  * if 'ed' style: 'dot' is set at start of last item printed,
 161  * and '+' points to next line.
 162  * Otherwise: 'dot' points to next item, '..' points to last.
 163  */
 164 static bool     db_ed_style = true;
 165
 166 /*
 167  * Utility routine - discard tokens through end-of-line.
 168  */
 169 void
 170 db_skip_to_eol(void)
 171 {
 172         int     t;
 173         do {
 174             t = db_read_token();
 175         } while (t != tEOL);
 176 }
 177
 178 /*
 179  * Results of command search.
 180  */
 181 #define CMD_UNIQUE      0
 182 #define CMD_FOUND       1
 183 #define CMD_NONE        2
 184 #define CMD_AMBIGUOUS   3
 185 #define CMD_HELP        4
 186
 187 static void     db_cmd_match(char *name, struct command *cmd,
 188                     struct command **cmdp, int *resultp);
 189 static void     db_cmd_list(struct command_table *table);
 190 static int      db_cmd_search(char *name, struct command_table *table,
 191                     struct command **cmdp);
 192 static void     db_command(struct command **last_cmdp,
 193                     struct command_table *cmd_table, int dopager);
 194
 195 /*
 196  * Initialize the command lists from the static tables.
 197  */
 198 void
 199 db_command_init(void)
 200 {
 201 #define N(a)    (sizeof(a) / sizeof(a[0]))
 202         int i;
 203
 204         for (i = 0; i < N(db_cmds); i++)
 205                 db_command_register(&db_cmd_table, &db_cmds[i]);
 206         for (i = 0; i < N(db_show_cmds); i++)
 207                 db_command_register(&db_show_table, &db_show_cmds[i]);
 208         for (i = 0; i < N(db_show_active_cmds); i++)
 209                 db_command_register(&db_show_active_table,
 210                     &db_show_active_cmds[i]);
 211         for (i = 0; i < N(db_show_all_cmds); i++)
 212                 db_command_register(&db_show_all_table, &db_show_all_cmds[i]);
 213 #undef N
 214 }
 215
 216 /*
 217  * Register a command.
 218  */
 219 void
 220 db_command_register(struct command_table *list, struct command *cmd)
 221 {
 222         struct command *c, *last;
 223
 224         last = NULL;
 225         LIST_FOREACH(c, list, next) {
 226                 int n = strcmp(cmd->name, c->name);
 227
 228                 /* Check that the command is not already present. */
 229                 if (n == 0) {
 230                         printf("%s: Warning, the command \"%s\" already exists;"
 231                              " ignoring request\n", __func__, cmd->name);
 232                         return;
 233                 }
 234                 if (n < 0) {
 235                         /* NB: keep list sorted lexicographically */
 236                         LIST_INSERT_BEFORE(c, cmd, next);
 237                         return;
 238                 }
 239                 last = c;
 240         }
 241         if (last == NULL)
 242                 LIST_INSERT_HEAD(list, cmd, next);
 243         else
 244                 LIST_INSERT_AFTER(last, cmd, next);
 245 }
 246
 247 /*
 248  * Remove a command previously registered with db_command_register.
 249  */
 250 void
 251 db_command_unregister(struct command_table *list, struct command *cmd)
 252 {
 253         struct command *c;
 254
 255         LIST_FOREACH(c, list, next) {
 256                 if (cmd == c) {
 257                         LIST_REMOVE(cmd, next);
 258                         return;
 259                 }
 260         }
 261         /* NB: intentionally quiet */
 262 }
 263
 264 /*
 265  * Helper function to match a single command.
 266  */
 267 static void
 268 db_cmd_match(char *name, struct command *cmd, struct command **cmdp,
 269     int *resultp)
 270 {
 271         char *lp, *rp;
 272         int c;
 273
 274         lp = name;
 275         rp = cmd->name;
 276         while ((c = *lp) == *rp) {
 277                 if (c == 0) {
 278                         /* complete match */
 279                         *cmdp = cmd;
 280                         *resultp = CMD_UNIQUE;
 281                         return;
 282                 }
 283                 lp++;
 284                 rp++;
 285         }
 286         if (c == 0) {
 287                 /* end of name, not end of command -
 288                    partial match */
 289                 if (*resultp == CMD_FOUND) {
 290                         *resultp = CMD_AMBIGUOUS;
 291                         /* but keep looking for a full match -
 292                            this lets us match single letters */
 293                 } else {
 294                         *cmdp = cmd;
 295                         *resultp = CMD_FOUND;
 296                 }
 297         }
 298 }
 299
 300 /*
 301  * Search for command prefix.
 302  */
 303 static int
 304 db_cmd_search(char *name, struct command_table *table, struct command **cmdp)
 305 {
 306         struct command  *cmd;
 307         int             result = CMD_NONE;
 308
 309         LIST_FOREACH(cmd, table, next) {
 310                 db_cmd_match(name,cmd,cmdp,&result);
 311                 if (result == CMD_UNIQUE)
 312                         break;
 313         }
 314
 315         if (result == CMD_NONE) {
 316                 /* check for 'help' */
 317                 if (name[0] == 'h' && name[1] == 'e'
 318                     && name[2] == 'l' && name[3] == 'p')
 319                         result = CMD_HELP;
 320         }
 321         return (result);
 322 }
 323
 324 static void
 325 db_cmd_list(struct command_table *table)
 326 {
 327         struct command  *cmd;
 328         int have_subcommands;
 329
 330         have_subcommands = 0;
 331         LIST_FOREACH(cmd, table, next) {
 332                 if (cmd->more != NULL)
 333                         have_subcommands++;
 334                 db_printf("%-16s", cmd->name);
 335                 db_end_line(16);
 336         }
 337
 338         if (have_subcommands > 0) {
 339                 db_printf("\nThe following have subcommands; append \"help\" "
 340                     "to list (e.g. \"show help\"):\n");
 341                 LIST_FOREACH(cmd, table, next) {
 342                         if (cmd->more == NULL)
 343                                 continue;
 344                         db_printf("%-16s", cmd->name);
 345                         db_end_line(16);
 346                 }
 347         }
 348 }
 349
 350 static void
 351 db_command(struct command **last_cmdp, struct command_table *cmd_table,
 352     int dopager)
 353 {
 354         struct command  *cmd = NULL;
 355         int             t;
 356         char            modif[TOK_STRING_SIZE];
 357         db_expr_t       addr, count;
 358         bool            have_addr = false;
 359         int             result;
 360
 361         t = db_read_token();
 362         if (t == tEOL) {
 363             /* empty line repeats last command, at 'next' */
 364             cmd = *last_cmdp;
 365             addr = (db_expr_t)db_next;
 366             have_addr = false;
 367             count = 1;
 368             modif[0] = '\0';
 369         }
 370         else if (t == tEXCL) {
 371             db_fncall((db_expr_t)0, (bool)false, (db_expr_t)0, (char *)0);
 372             return;
 373         }
 374         else if (t != tIDENT) {
 375             db_printf("Unrecognized input; use \"help\" "
 376                 "to list available commands\n");
 377             db_flush_lex();
 378             return;
 379         }
 380         else {
 381             /*
 382              * Search for command
 383              */
 384             while (cmd_table) {
 385                 result = db_cmd_search(db_tok_string,
 386                                        cmd_table,
 387                                        &cmd);
 388                 switch (result) {
 389                     case CMD_NONE:
 390                         db_printf("No such command; use \"help\" "
 391                             "to list available commands\n");
 392                         db_flush_lex();
 393                         return;
 394                     case CMD_AMBIGUOUS:
 395                         db_printf("Ambiguous\n");
 396                         db_flush_lex();
 397                         return;
 398                     case CMD_HELP:
 399                         if (cmd_table == &db_cmd_table) {
 400                             db_printf("This is ddb(4), the kernel debugger; "
 401                                 "see http://man.freebsd.org/ddb/4 for help.\n");
 402                             db_printf("Use \"bt\" for backtrace, \"dump\" for "
 403                                 "kernel core dump, \"reset\" to reboot.\n");
 404                             db_printf("Available commands:\n");
 405                         }
 406                         db_cmd_list(cmd_table);
 407                         db_flush_lex();
 408                         return;
 409                     default:
 410                         break;
 411                 }
 412                 if ((cmd_table = cmd->more) != NULL) {
 413                     t = db_read_token();
 414                     if (t != tIDENT) {
 415                         db_printf("Subcommand required; "
 416                             "available subcommands:\n");
 417                         db_cmd_list(cmd_table);
 418                         db_flush_lex();
 419                         return;
 420                     }
 421                 }
 422             }
 423
 424             if ((cmd->flag & CS_OWN) == 0) {
 425                 /*
 426                  * Standard syntax:
 427                  * command [/modifier] [addr] [,count]
 428                  */
 429                 t = db_read_token();
 430                 if (t == tSLASH) {
 431                     t = db_read_token();
 432                     if (t != tIDENT) {
 433                         db_printf("Bad modifier\n");
 434                         db_flush_lex();
 435                         return;
 436                     }
 437                     db_strcpy(modif, db_tok_string);
 438                 }
 439                 else {
 440                     db_unread_token(t);
 441                     modif[0] = '\0';
 442                 }
 443
 444                 if (db_expression(&addr)) {
 445                     db_dot = (db_addr_t) addr;
 446                     db_last_addr = db_dot;
 447                     have_addr = true;
 448                 }
 449                 else {
 450                     addr = (db_expr_t) db_dot;
 451                     have_addr = false;
 452                 }
 453                 t = db_read_token();
 454                 if (t == tCOMMA) {
 455                     if (!db_expression(&count)) {
 456                         db_printf("Count missing\n");
 457                         db_flush_lex();
 458                         return;
 459                     }
 460                 }
 461                 else {
 462                     db_unread_token(t);
 463                     count = -1;
 464                 }
 465                 if ((cmd->flag & CS_MORE) == 0) {
 466                     db_skip_to_eol();
 467                 }
 468             }
 469         }
 470         *last_cmdp = cmd;
 471         if (cmd != NULL) {
 472             /*
 473              * Execute the command.
 474              */
 475             if (dopager)
 476                 db_enable_pager();
 477             else
 478                 db_disable_pager();
 479             (*cmd->fcn)(addr, have_addr, count, modif);
 480             if (dopager)
 481                 db_disable_pager();
 482
 483             if (cmd->flag & CS_SET_DOT) {
 484                 /*
 485                  * If command changes dot, set dot to
 486                  * previous address displayed (if 'ed' style).
 487                  */
 488                 if (db_ed_style) {
 489                     db_dot = db_prev;
 490                 }
 491                 else {
 492                     db_dot = db_next;
 493                 }
 494             }
 495             else {
 496                 /*
 497                  * If command does not change dot,
 498                  * set 'next' location to be the same.
 499                  */
 500                 db_next = db_dot;
 501             }
 502         }
 503 }
 504
 505 /*
 506  * At least one non-optional command must be implemented using
 507  * DB_COMMAND() so that db_cmd_set gets created.  Here is one.
 508  */
 509 DB_COMMAND(panic, db_panic)
 510 {
 511         db_disable_pager();
 512         panic("from debugger");
 513 }
 514
 515 void
 516 db_command_loop(void)
 517 {
 518         /*
 519          * Initialize 'prev' and 'next' to dot.
 520          */
 521         db_prev = db_dot;
 522         db_next = db_dot;
 523
 524         db_cmd_loop_done = 0;
 525         while (!db_cmd_loop_done) {
 526             if (db_print_position() != 0)
 527                 db_printf("\n");
 528
 529             db_printf("db> ");
 530             (void) db_read_line();
 531
 532             db_command(&db_last_command, &db_cmd_table, /* dopager */ 1);
 533         }
 534 }
 535
 536 /*
 537  * Execute a command on behalf of a script.  The caller is responsible for
 538  * making sure that the command string is < DB_MAXLINE or it will be
 539  * truncated.
 540  *
 541  * XXXRW: Runs by injecting faked input into DDB input stream; it would be
 542  * nicer to use an alternative approach that didn't mess with the previous
 543  * command buffer.
 544  */
 545 void
 546 db_command_script(const char *command)
 547 {
 548         db_prev = db_next = db_dot;
 549         db_inject_line(command);
 550         db_command(&db_last_command, &db_cmd_table, /* dopager */ 0);
 551 }
 552
 553 void
 554 db_error(const char *s)
 555 {
 556         if (s)
 557             db_printf("%s", s);
 558         db_flush_lex();
 559         kdb_reenter();
 560 }
 561
 562 static void
 563 db_dump(db_expr_t dummy, bool dummy2, db_expr_t dummy3, char *dummy4)
 564 {
 565         int error;
 566
 567         if (textdump_pending) {
 568                 db_printf("textdump_pending set.\n"
 569                     "run \"textdump unset\" first or \"textdump dump\" for a textdump.\n");
 570                 return;
 571         }
 572         error = doadump(false);
 573         if (error) {
 574                 db_printf("Cannot dump: ");
 575                 switch (error) {
 576                 case EBUSY:
 577                         db_printf("debugger got invoked while dumping.\n");
 578                         break;
 579                 case ENXIO:
 580                         db_printf("no dump device specified.\n");
 581                         break;
 582                 default:
 583                         db_printf("unknown error (error=%d).\n", error);
 584                         break;
 585                 }
 586         }
 587 }
 588
 589 /*
 590  * Call random function:
 591  * !expr(arg,arg,arg)
 592  */
 593
 594 /* The generic implementation supports a maximum of 10 arguments. */
 595 typedef db_expr_t __db_f(db_expr_t, db_expr_t, db_expr_t, db_expr_t,
 596     db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t);
 597
 598 static __inline int
 599 db_fncall_generic(db_expr_t addr, db_expr_t *rv, int nargs, db_expr_t args[])
 600 {
 601         __db_f *f = (__db_f *)addr;
 602
 603         if (nargs > 10) {
 604                 db_printf("Too many arguments (max 10)\n");
 605                 return (0);
 606         }
 607         *rv = (*f)(args[0], args[1], args[2], args[3], args[4], args[5],
 608             args[6], args[7], args[8], args[9]);
 609         return (1);
 610 }
 611
 612 static void
 613 db_fncall(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 614 {
 615         db_expr_t       fn_addr;
 616         db_expr_t       args[DB_MAXARGS];
 617         int             nargs = 0;
 618         db_expr_t       retval;
 619         int             t;
 620
 621         if (!db_expression(&fn_addr)) {
 622             db_printf("Bad function\n");
 623             db_flush_lex();
 624             return;
 625         }
 626
 627         t = db_read_token();
 628         if (t == tLPAREN) {
 629             if (db_expression(&args[0])) {
 630                 nargs++;
 631                 while ((t = db_read_token()) == tCOMMA) {
 632                     if (nargs == DB_MAXARGS) {
 633                         db_printf("Too many arguments (max %d)\n", DB_MAXARGS);
 634                         db_flush_lex();
 635                         return;
 636                     }
 637                     if (!db_expression(&args[nargs])) {
 638                         db_printf("Argument missing\n");
 639                         db_flush_lex();
 640                         return;
 641                     }
 642                     nargs++;
 643                 }
 644                 db_unread_token(t);
 645             }
 646             if (db_read_token() != tRPAREN) {
 647                 db_printf("Mismatched parens\n");
 648                 db_flush_lex();
 649                 return;
 650             }
 651         }
 652         db_skip_to_eol();
 653         db_disable_pager();
 654
 655         if (DB_CALL(fn_addr, &retval, nargs, args))
 656                 db_printf("= %#lr\n", (long)retval);
 657 }
 658
 659 static void
 660 db_halt(db_expr_t dummy, bool dummy2, db_expr_t dummy3, char *dummy4)
 661 {
 662
 663         cpu_halt();
 664 }
 665
 666 static void
 667 db_kill(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 668 {
 669         db_expr_t old_radix, pid, sig;
 670         struct proc *p;
 671
 672 #define DB_ERROR(f)     do { db_printf f; db_flush_lex(); goto out; } while (0)
 673
 674         /*
 675          * PIDs and signal numbers are typically represented in base
 676          * 10, so make that the default here.  It can, of course, be
 677          * overridden by specifying a prefix.
 678          */
 679         old_radix = db_radix;
 680         db_radix = 10;
 681         /* Retrieve arguments. */
 682         if (!db_expression(&sig))
 683                 DB_ERROR(("Missing signal number\n"));
 684         if (!db_expression(&pid))
 685                 DB_ERROR(("Missing process ID\n"));
 686         db_skip_to_eol();
 687         if (!_SIG_VALID(sig))
 688                 DB_ERROR(("Signal number out of range\n"));
 689
 690         /*
 691          * Find the process in question.  allproc_lock is not needed
 692          * since we're in DDB.
 693          */
 694         /* sx_slock(&allproc_lock); */
 695         FOREACH_PROC_IN_SYSTEM(p)
 696             if (p->p_pid == pid)
 697                     break;
 698         /* sx_sunlock(&allproc_lock); */
 699         if (p == NULL)
 700                 DB_ERROR(("Can't find process with pid %ld\n", (long) pid));
 701
 702         /* If it's already locked, bail; otherwise, do the deed. */
 703         if (PROC_TRYLOCK(p) == 0)
 704                 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid));
 705         else {
 706                 pksignal(p, sig, NULL);
 707                 PROC_UNLOCK(p);
 708         }
 709
 710 out:
 711         db_radix = old_radix;
 712 #undef DB_ERROR
 713 }
 714
 715 /*
 716  * Reboot.  In case there is an additional argument, take it as delay in
 717  * seconds.  Default to 15s if we cannot parse it and make sure we will
 718  * never wait longer than 1 week.  Some code is similar to
 719  * kern_shutdown.c:shutdown_panic().
 720  */
 721 #ifndef DB_RESET_MAXDELAY
 722 #define DB_RESET_MAXDELAY       (3600 * 24 * 7)
 723 #endif
 724
 725 static void
 726 db_reset(db_expr_t addr, bool have_addr, db_expr_t count __unused,
 727     char *modif __unused)
 728 {
 729         int delay, loop;
 730
 731         if (have_addr) {
 732                 delay = (int)db_hex2dec(addr);
 733
 734                 /* If we parse to fail, use 15s. */
 735                 if (delay == -1)
 736                         delay = 15;
 737
 738                 /* Cap at one week. */
 739                 if ((uintmax_t)delay > (uintmax_t)DB_RESET_MAXDELAY)
 740                         delay = DB_RESET_MAXDELAY;
 741
 742                 db_printf("Automatic reboot in %d seconds - "
 743                     "press a key on the console to abort\n", delay);
 744                 for (loop = delay * 10; loop > 0; --loop) {
 745                         DELAY(1000 * 100); /* 1/10th second */
 746                         /* Did user type a key? */
 747                         if (cncheckc() != -1)
 748                                 return;
 749                 }
 750         }
 751
 752         cpu_reset();
 753 }
 754
 755 static void
 756 db_watchdog(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 757 {
 758         db_expr_t old_radix, tout;
 759         int err, i;
 760
 761         old_radix = db_radix;
 762         db_radix = 10;
 763         err = db_expression(&tout);
 764         db_skip_to_eol();
 765         db_radix = old_radix;
 766
 767         /* If no argument is provided the watchdog will just be disabled. */
 768         if (err == 0) {
 769                 db_printf("No argument provided, disabling watchdog\n");
 770                 tout = 0;
 771         } else if ((tout & WD_INTERVAL) == WD_TO_NEVER) {
 772                 db_error("Out of range watchdog interval\n");
 773                 return;
 774         }
 775         EVENTHANDLER_INVOKE(watchdog_list, tout, &i);
 776 }
 777
 778 static void
 779 db_gdb(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 780 {
 781
 782         if (kdb_dbbe_select("gdb") != 0) {
 783                 db_printf("The remote GDB backend could not be selected.\n");
 784                 return;
 785         }
 786         /*
 787          * Mark that we are done in the debugger.  kdb_trap()
 788          * should re-enter with the new backend.
 789          */
 790         db_cmd_loop_done = 1;
 791         db_printf("(ctrl-c will return control to ddb)\n");
 792 }
 793
 794 static void
 795 db_stack_trace(db_expr_t tid, bool hastid, db_expr_t count, char *modif)
 796 {
 797         struct thread *td;
 798         db_expr_t radix;
 799         pid_t pid;
 800         int t;
 801
 802         /*
 803          * We parse our own arguments. We don't like the default radix.
 804          */
 805         radix = db_radix;
 806         db_radix = 10;
 807         hastid = db_expression(&tid);
 808         t = db_read_token();
 809         if (t == tCOMMA) {
 810                 if (!db_expression(&count)) {
 811                         db_printf("Count missing\n");
 812                         db_flush_lex();
 813                         return;
 814                 }
 815         } else {
 816                 db_unread_token(t);
 817                 count = -1;
 818         }
 819         db_skip_to_eol();
 820         db_radix = radix;
 821
 822         if (hastid) {
 823                 td = kdb_thr_lookup((lwpid_t)tid);
 824                 if (td == NULL)
 825                         td = kdb_thr_from_pid((pid_t)tid);
 826                 if (td == NULL) {
 827                         db_printf("Thread %d not found\n", (int)tid);
 828                         return;
 829                 }
 830         } else
 831                 td = kdb_thread;
 832         if (td->td_proc != NULL)
 833                 pid = td->td_proc->p_pid;
 834         else
 835                 pid = -1;
 836         db_printf("Tracing pid %d tid %ld td %p\n", pid, (long)td->td_tid, td);
 837         db_trace_thread(td, count);
 838 }
 839
 840 static void
 841 _db_stack_trace_all(bool active_only)
 842 {
 843         struct proc *p;
 844         struct thread *td;
 845         jmp_buf jb;
 846         void *prev_jb;
 847
 848         FOREACH_PROC_IN_SYSTEM(p) {
 849                 prev_jb = kdb_jmpbuf(jb);
 850                 if (setjmp(jb) == 0) {
 851                         FOREACH_THREAD_IN_PROC(p, td) {
 852                                 if (td->td_state == TDS_RUNNING)
 853                                         db_printf("\nTracing command %s pid %d"
 854                                             " tid %ld td %p (CPU %d)\n",
 855                                             p->p_comm, p->p_pid,
 856                                             (long)td->td_tid, td,
 857                                             td->td_oncpu);
 858                                 else if (active_only)
 859                                         continue;
 860                                 else
 861                                         db_printf("\nTracing command %s pid %d"
 862                                             " tid %ld td %p\n", p->p_comm,
 863                                             p->p_pid, (long)td->td_tid, td);
 864                                 db_trace_thread(td, -1);
 865                                 if (db_pager_quit) {
 866                                         kdb_jmpbuf(prev_jb);
 867                                         return;
 868                                 }
 869                         }
 870                 }
 871                 kdb_jmpbuf(prev_jb);
 872         }
 873 }
 874
 875 static void
 876 db_stack_trace_active(db_expr_t dummy, bool dummy2, db_expr_t dummy3,
 877     char *dummy4)
 878 {
 879
 880         _db_stack_trace_all(true);
 881 }
 882
 883 static void
 884 db_stack_trace_all(db_expr_t dummy, bool dummy2, db_expr_t dummy3,
 885     char *dummy4)
 886 {
 887
 888         _db_stack_trace_all(false);
 889 }
 890
 891 /*
 892  * Take the parsed expression value from the command line that was parsed
 893  * as a hexadecimal value and convert it as if the expression was parsed
 894  * as a decimal value.  Returns -1 if the expression was not a valid
 895  * decimal value.
 896  */
 897 db_expr_t
 898 db_hex2dec(db_expr_t expr)
 899 {
 900         uintptr_t x, y;
 901         db_expr_t val;
 902
 903         y = 1;
 904         val = 0;
 905         x = expr;
 906         while (x != 0) {
 907                 if (x % 16 > 9)
 908                         return (-1);
 909                 val += (x % 16) * (y);
 910                 x >>= 4;
 911                 y *= 10;
 912         }
 913         return (val);
 914 }