sys/ddb/db_command.c

   1 /*-
   2  * SPDX-License-Identifier: MIT-CMU
   3  *
   4  * Mach Operating System
   5  * Copyright (c) 1991,1990 Carnegie Mellon University
   6  * All Rights Reserved.
   7  *
   8  * Permission to use, copy, modify and distribute this software and its
   9  * documentation is hereby granted, provided that both the copyright
  10  * notice and this permission notice appear in all copies of the
  11  * software, derivative works or modified versions, and any portions
  12  * thereof, and that both notices appear in supporting documentation.
  13  *
  14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
  15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  16  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  17  *
  18  * Carnegie Mellon requests users of this software to return to
  19  *
  20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  21  *  School of Computer Science
  22  *  Carnegie Mellon University
  23  *  Pittsburgh PA 15213-3890
  24  *
  25  * any improvements or extensions that they make and grant Carnegie the
  26  * rights to redistribute these changes.
  27  */
  28 /*
  29  *      Author: David B. Golub, Carnegie Mellon University
  30  *      Date:   7/90
  31  */
  32 /*
  33  * Command dispatcher.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 __FBSDID("$FreeBSD$");
  38
  39 #include <sys/param.h>
  40 #include <sys/conf.h>
  41 #include <sys/cons.h>
  42 #include <sys/eventhandler.h>
  43 #include <sys/kdb.h>
  44 #include <sys/kernel.h>
  45 #include <sys/linker_set.h>
  46 #include <sys/lock.h>
  47 #include <sys/mutex.h>
  48 #include <sys/proc.h>
  49 #include <sys/reboot.h>
  50 #include <sys/signalvar.h>
  51 #include <sys/systm.h>
  52 #include <sys/watchdog.h>
  53
  54 #include <ddb/ddb.h>
  55 #include <ddb/db_command.h>
  56 #include <ddb/db_lex.h>
  57 #include <ddb/db_output.h>
  58
  59 #include <machine/cpu.h>
  60 #include <machine/setjmp.h>
  61
  62 /*
  63  * Exported global variables
  64  */
  65 int             db_cmd_loop_done;
  66 db_addr_t       db_dot;
  67 db_addr_t       db_last_addr;
  68 db_addr_t       db_prev;
  69 db_addr_t       db_next;
  70
  71 static db_cmdfcn_t      db_dump;
  72 static db_cmdfcn_t      db_fncall;
  73 static db_cmdfcn_t      db_gdb;
  74 static db_cmdfcn_t      db_halt;
  75 static db_cmdfcn_t      db_kill;
  76 static db_cmdfcn_t      db_reset;
  77 static db_cmdfcn_t      db_stack_trace;
  78 static db_cmdfcn_t      db_stack_trace_active;
  79 static db_cmdfcn_t      db_stack_trace_all;
  80 static db_cmdfcn_t      db_watchdog;
  81
  82 #define DB_CMD(_name, _func, _flags)    \
  83 {                                       \
  84         .name = (_name),                \
  85         .fcn =  (_func),                \
  86         .flag = (_flags),               \
  87         .more = NULL,                   \
  88 }
  89 #define DB_TABLE(_name, _more)          \
  90 {                                       \
  91         .name = (_name),                \
  92         .fcn =  NULL,                   \
  93         .more = (_more),                \
  94 }
  95
  96 static struct db_command db_show_active_cmds[] = {
  97         DB_CMD("trace",         db_stack_trace_active,  0),
  98 };
  99 struct db_command_table db_show_active_table =
 100     LIST_HEAD_INITIALIZER(db_show_active_table);
 101
 102 static struct db_command db_show_all_cmds[] = {
 103         DB_CMD("trace",         db_stack_trace_all,     0),
 104 };
 105 struct db_command_table db_show_all_table =
 106     LIST_HEAD_INITIALIZER(db_show_all_table);
 107
 108 static struct db_command db_show_cmds[] = {
 109         DB_TABLE("active",      &db_show_active_table),
 110         DB_TABLE("all",         &db_show_all_table),
 111         DB_CMD("registers",     db_show_regs,           0),
 112         DB_CMD("breaks",        db_listbreak_cmd,       0),
 113         DB_CMD("threads",       db_show_threads,        0),
 114 };
 115 struct db_command_table db_show_table = LIST_HEAD_INITIALIZER(db_show_table);
 116
 117 static struct db_command db_cmds[] = {
 118         DB_TABLE("show",        &db_show_table),
 119         DB_CMD("print",         db_print_cmd,           0),
 120         DB_CMD("p",             db_print_cmd,           0),
 121         DB_CMD("examine",       db_examine_cmd,         CS_SET_DOT),
 122         DB_CMD("x",             db_examine_cmd,         CS_SET_DOT),
 123         DB_CMD("search",        db_search_cmd,          CS_OWN|CS_SET_DOT),
 124         DB_CMD("set",           db_set_cmd,             CS_OWN),
 125         DB_CMD("write",         db_write_cmd,           CS_MORE|CS_SET_DOT),
 126         DB_CMD("w",             db_write_cmd,           CS_MORE|CS_SET_DOT),
 127         DB_CMD("delete",        db_delete_cmd,          0),
 128         DB_CMD("d",             db_delete_cmd,          0),
 129         DB_CMD("dump",          db_dump,                0),
 130         DB_CMD("break",         db_breakpoint_cmd,      0),
 131         DB_CMD("b",             db_breakpoint_cmd,      0),
 132         DB_CMD("dwatch",        db_deletewatch_cmd,     0),
 133         DB_CMD("watch",         db_watchpoint_cmd,      CS_MORE),
 134         DB_CMD("dhwatch",       db_deletehwatch_cmd,    0),
 135         DB_CMD("hwatch",        db_hwatchpoint_cmd,     0),
 136         DB_CMD("step",          db_single_step_cmd,     0),
 137         DB_CMD("s",             db_single_step_cmd,     0),
 138         DB_CMD("continue",      db_continue_cmd,        0),
 139         DB_CMD("c",             db_continue_cmd,        0),
 140         DB_CMD("until",         db_trace_until_call_cmd, 0),
 141         DB_CMD("next",          db_trace_until_matching_cmd, 0),
 142         DB_CMD("match",         db_trace_until_matching_cmd, 0),
 143         DB_CMD("trace",         db_stack_trace,         CS_OWN),
 144         DB_CMD("t",             db_stack_trace,         CS_OWN),
 145         /* XXX alias for active trace */
 146         DB_CMD("acttrace",      db_stack_trace_active,  0),
 147         /* XXX alias for all trace */
 148         DB_CMD("alltrace",      db_stack_trace_all,     0),
 149         DB_CMD("where",         db_stack_trace,         CS_OWN),
 150         DB_CMD("bt",            db_stack_trace,         CS_OWN),
 151         DB_CMD("call",          db_fncall,              CS_OWN),
 152         DB_CMD("ps",            db_ps,                  0),
 153         DB_CMD("gdb",           db_gdb,                 0),
 154         DB_CMD("halt",          db_halt,                0),
 155         DB_CMD("reboot",        db_reset,               0),
 156         DB_CMD("reset",         db_reset,               0),
 157         DB_CMD("kill",          db_kill,                CS_OWN),
 158         DB_CMD("watchdog",      db_watchdog,            CS_OWN),
 159         DB_CMD("thread",        db_set_thread,          0),
 160         DB_CMD("run",           db_run_cmd,             CS_OWN),
 161         DB_CMD("script",        db_script_cmd,          CS_OWN),
 162         DB_CMD("scripts",       db_scripts_cmd,         0),
 163         DB_CMD("unscript",      db_unscript_cmd,        CS_OWN),
 164         DB_CMD("capture",       db_capture_cmd,         CS_OWN),
 165         DB_CMD("textdump",      db_textdump_cmd,        CS_OWN),
 166         DB_CMD("findstack",     db_findstack_cmd,       0),
 167 };
 168 struct db_command_table db_cmd_table = LIST_HEAD_INITIALIZER(db_cmd_table);
 169
 170 #undef DB_CMD
 171 #undef DB_TABLE
 172
 173 static struct db_command *db_last_command = NULL;
 174
 175 /*
 176  * if 'ed' style: 'dot' is set at start of last item printed,
 177  * and '+' points to next line.
 178  * Otherwise: 'dot' points to next item, '..' points to last.
 179  */
 180 static bool     db_ed_style = true;
 181
 182 /*
 183  * Utility routine - discard tokens through end-of-line.
 184  */
 185 void
 186 db_skip_to_eol(void)
 187 {
 188         int t;
 189
 190         do {
 191                 t = db_read_token();
 192         } while (t != tEOL);
 193 }
 194
 195 /*
 196  * Results of command search.
 197  */
 198 #define CMD_UNIQUE      0
 199 #define CMD_FOUND       1
 200 #define CMD_NONE        2
 201 #define CMD_AMBIGUOUS   3
 202 #define CMD_HELP        4
 203
 204 static void     db_cmd_match(char *name, struct db_command *cmd,
 205                     struct db_command **cmdp, int *resultp);
 206 static void     db_cmd_list(struct db_command_table *table);
 207 static int      db_cmd_search(char *name, struct db_command_table *table,
 208                     struct db_command **cmdp);
 209 static void     db_command(struct db_command **last_cmdp,
 210                     struct db_command_table *cmd_table, bool dopager);
 211
 212 /*
 213  * Initialize the command lists from the static tables.
 214  */
 215 void
 216 db_command_init(void)
 217 {
 218         int i;
 219
 220         for (i = 0; i < nitems(db_cmds); i++)
 221                 db_command_register(&db_cmd_table, &db_cmds[i]);
 222         for (i = 0; i < nitems(db_show_cmds); i++)
 223                 db_command_register(&db_show_table, &db_show_cmds[i]);
 224         for (i = 0; i < nitems(db_show_active_cmds); i++)
 225                 db_command_register(&db_show_active_table,
 226                     &db_show_active_cmds[i]);
 227         for (i = 0; i < nitems(db_show_all_cmds); i++)
 228                 db_command_register(&db_show_all_table, &db_show_all_cmds[i]);
 229 }
 230
 231 /*
 232  * Register a command.
 233  */
 234 void
 235 db_command_register(struct db_command_table *list, struct db_command *cmd)
 236 {
 237         struct db_command *c, *last;
 238
 239         last = NULL;
 240         LIST_FOREACH(c, list, next) {
 241                 int n = strcmp(cmd->name, c->name);
 242
 243                 /* Check that the command is not already present. */
 244                 if (n == 0) {
 245                         printf("%s: Warning, the command \"%s\" already exists;"
 246                              " ignoring request\n", __func__, cmd->name);
 247                         return;
 248                 }
 249                 if (n < 0) {
 250                         /* NB: keep list sorted lexicographically */
 251                         LIST_INSERT_BEFORE(c, cmd, next);
 252                         return;
 253                 }
 254                 last = c;
 255         }
 256         if (last == NULL)
 257                 LIST_INSERT_HEAD(list, cmd, next);
 258         else
 259                 LIST_INSERT_AFTER(last, cmd, next);
 260 }
 261
 262 /*
 263  * Remove a command previously registered with db_command_register.
 264  */
 265 void
 266 db_command_unregister(struct db_command_table *list, struct db_command *cmd)
 267 {
 268         struct db_command *c;
 269
 270         LIST_FOREACH(c, list, next) {
 271                 if (cmd == c) {
 272                         LIST_REMOVE(cmd, next);
 273                         return;
 274                 }
 275         }
 276         /* NB: intentionally quiet */
 277 }
 278
 279 /*
 280  * Helper function to match a single command.
 281  */
 282 static void
 283 db_cmd_match(char *name, struct db_command *cmd, struct db_command **cmdp,
 284     int *resultp)
 285 {
 286         char *lp, *rp;
 287         int c;
 288
 289         lp = name;
 290         rp = cmd->name;
 291         while ((c = *lp) == *rp) {
 292                 if (c == 0) {
 293                         /* complete match */
 294                         *cmdp = cmd;
 295                         *resultp = CMD_UNIQUE;
 296                         return;
 297                 }
 298                 lp++;
 299                 rp++;
 300         }
 301         if (c == 0) {
 302                 /* end of name, not end of command -
 303                    partial match */
 304                 if (*resultp == CMD_FOUND) {
 305                         *resultp = CMD_AMBIGUOUS;
 306                         /* but keep looking for a full match -
 307                            this lets us match single letters */
 308                 } else if (*resultp == CMD_NONE) {
 309                         *cmdp = cmd;
 310                         *resultp = CMD_FOUND;
 311                 }
 312         }
 313 }
 314
 315 /*
 316  * Search for command prefix.
 317  */
 318 static int
 319 db_cmd_search(char *name, struct db_command_table *table,
 320     struct db_command **cmdp)
 321 {
 322         struct db_command *cmd;
 323         int result = CMD_NONE;
 324
 325         LIST_FOREACH(cmd, table, next) {
 326                 db_cmd_match(name,cmd,cmdp,&result);
 327                 if (result == CMD_UNIQUE)
 328                         break;
 329         }
 330
 331         if (result == CMD_NONE) {
 332                 /* check for 'help' */
 333                 if (name[0] == 'h' && name[1] == 'e'
 334                     && name[2] == 'l' && name[3] == 'p')
 335                         result = CMD_HELP;
 336         }
 337         return (result);
 338 }
 339
 340 static void
 341 db_cmd_list(struct db_command_table *table)
 342 {
 343         struct db_command *cmd;
 344         int have_subcommands;
 345
 346         have_subcommands = 0;
 347         LIST_FOREACH(cmd, table, next) {
 348                 if (cmd->more != NULL)
 349                         have_subcommands++;
 350                 db_printf("%-16s", cmd->name);
 351                 db_end_line(16);
 352         }
 353
 354         if (have_subcommands > 0) {
 355                 db_printf("\nThe following have subcommands; append \"help\" "
 356                     "to list (e.g. \"show help\"):\n");
 357                 LIST_FOREACH(cmd, table, next) {
 358                         if (cmd->more == NULL)
 359                                 continue;
 360                         db_printf("%-16s", cmd->name);
 361                         db_end_line(16);
 362                 }
 363         }
 364 }
 365
 366 static void
 367 db_command(struct db_command **last_cmdp, struct db_command_table *cmd_table,
 368     bool dopager)
 369 {
 370         char modif[TOK_STRING_SIZE];
 371         struct db_command *cmd = NULL;
 372         db_expr_t addr, count;
 373         int t, result;
 374         bool have_addr = false;
 375
 376         t = db_read_token();
 377         if (t == tEOL) {
 378                 /* empty line repeats last command, at 'next' */
 379                 cmd = *last_cmdp;
 380                 addr = (db_expr_t)db_next;
 381                 have_addr = false;
 382                 count = 1;
 383                 modif[0] = '\0';
 384         } else if (t == tEXCL) {
 385                 db_fncall((db_expr_t)0, false, (db_expr_t)0, NULL);
 386                 return;
 387         } else if (t != tIDENT) {
 388                 db_printf("Unrecognized input; use \"help\" "
 389                     "to list available commands\n");
 390                 db_flush_lex();
 391                 return;
 392         } else {
 393                 /*
 394                  * Search for command
 395                  */
 396                 while (cmd_table != NULL) {
 397                         result = db_cmd_search(db_tok_string, cmd_table, &cmd);
 398                         switch (result) {
 399                         case CMD_NONE:
 400                                 db_printf("No such command; use \"help\" "
 401                                     "to list available commands\n");
 402                                 db_flush_lex();
 403                                 return;
 404                         case CMD_AMBIGUOUS:
 405                                 db_printf("Ambiguous\n");
 406                                 db_flush_lex();
 407                                 return;
 408                         case CMD_HELP:
 409                                 if (cmd_table == &db_cmd_table) {
 410                                         db_printf("This is ddb(4), the kernel debugger; "
 411                                             "see https://man.FreeBSD.org/ddb/4 for help.\n");
 412                                         db_printf("Use \"bt\" for backtrace, \"dump\" for "
 413                                             "kernel core dump, \"reset\" to reboot.\n");
 414                                         db_printf("Available commands:\n");
 415                                 }
 416                                 db_cmd_list(cmd_table);
 417                                 db_flush_lex();
 418                                 return;
 419                         case CMD_UNIQUE:
 420                         case CMD_FOUND:
 421                                 break;
 422                         }
 423                         if ((cmd_table = cmd->more) != NULL) {
 424                                 t = db_read_token();
 425                                 if (t != tIDENT) {
 426                                         db_printf("Subcommand required; "
 427                                             "available subcommands:\n");
 428                                         db_cmd_list(cmd_table);
 429                                         db_flush_lex();
 430                                         return;
 431                                 }
 432                         }
 433                 }
 434
 435                 if ((cmd->flag & CS_OWN) == 0) {
 436                         /*
 437                          * Standard syntax:
 438                          * command [/modifier] [addr] [,count]
 439                          */
 440                         t = db_read_token();
 441                         if (t == tSLASH) {
 442                                 t = db_read_token();
 443                                 if (t != tIDENT) {
 444                                         db_printf("Bad modifier\n");
 445                                         db_flush_lex();
 446                                         return;
 447                                 }
 448                                 db_strcpy(modif, db_tok_string);
 449                         } else {
 450                                 db_unread_token(t);
 451                                 modif[0] = '\0';
 452                         }
 453
 454                         if (db_expression(&addr)) {
 455                                 db_dot = (db_addr_t) addr;
 456                                 db_last_addr = db_dot;
 457                                 have_addr = true;
 458                         } else {
 459                                 addr = (db_expr_t) db_dot;
 460                                 have_addr = false;
 461                         }
 462
 463                         t = db_read_token();
 464                         if (t == tCOMMA) {
 465                                 if (!db_expression(&count)) {
 466                                         db_printf("Count missing\n");
 467                                         db_flush_lex();
 468                                         return;
 469                                 }
 470                         } else {
 471                                 db_unread_token(t);
 472                                 count = -1;
 473                         }
 474
 475                         if ((cmd->flag & CS_MORE) == 0) {
 476                                 db_skip_to_eol();
 477                         }
 478                 }
 479         }
 480
 481         *last_cmdp = cmd;
 482         if (cmd != NULL) {
 483                 /*
 484                  * Execute the command.
 485                  */
 486                 if (dopager)
 487                         db_enable_pager();
 488                 else
 489                         db_disable_pager();
 490                 (*cmd->fcn)(addr, have_addr, count, modif);
 491                 if (dopager)
 492                         db_disable_pager();
 493
 494                 if (cmd->flag & CS_SET_DOT) {
 495                         /*
 496                          * If command changes dot, set dot to previous address
 497                          * displayed (if 'ed' style).
 498                          */
 499                         db_dot = db_ed_style ? db_prev : db_next;
 500                 } else {
 501                         /*
 502                          * If command does not change dot, set 'next' location
 503                          * to be the same.
 504                          */
 505                         db_next = db_dot;
 506                 }
 507         }
 508 }
 509
 510 /*
 511  * At least one non-optional command must be implemented using
 512  * DB_COMMAND() so that db_cmd_set gets created.  Here is one.
 513  */
 514 DB_COMMAND(panic, db_panic)
 515 {
 516         db_disable_pager();
 517         panic("from debugger");
 518 }
 519
 520 void
 521 db_command_loop(void)
 522 {
 523         /*
 524          * Initialize 'prev' and 'next' to dot.
 525          */
 526         db_prev = db_dot;
 527         db_next = db_dot;
 528
 529         db_cmd_loop_done = 0;
 530         while (!db_cmd_loop_done) {
 531                 if (db_print_position() != 0)
 532                         db_printf("\n");
 533
 534                 db_printf("db> ");
 535                 (void)db_read_line();
 536
 537                 db_command(&db_last_command, &db_cmd_table, /* dopager */ true);
 538         }
 539 }
 540
 541 /*
 542  * Execute a command on behalf of a script.  The caller is responsible for
 543  * making sure that the command string is < DB_MAXLINE or it will be
 544  * truncated.
 545  *
 546  * XXXRW: Runs by injecting faked input into DDB input stream; it would be
 547  * nicer to use an alternative approach that didn't mess with the previous
 548  * command buffer.
 549  */
 550 void
 551 db_command_script(const char *command)
 552 {
 553         db_prev = db_next = db_dot;
 554         db_inject_line(command);
 555         db_command(&db_last_command, &db_cmd_table, /* dopager */ false);
 556 }
 557
 558 void
 559 db_error(const char *s)
 560 {
 561         if (s)
 562             db_printf("%s", s);
 563         db_flush_lex();
 564         kdb_reenter_silent();
 565 }
 566
 567 static void
 568 db_dump(db_expr_t dummy, bool dummy2, db_expr_t dummy3, char *dummy4)
 569 {
 570         int error;
 571
 572         if (textdump_pending) {
 573                 db_printf("textdump_pending set.\n"
 574                     "run \"textdump unset\" first or \"textdump dump\" for a textdump.\n");
 575                 return;
 576         }
 577         error = doadump(false);
 578         if (error) {
 579                 db_printf("Cannot dump: ");
 580                 switch (error) {
 581                 case EBUSY:
 582                         db_printf("debugger got invoked while dumping.\n");
 583                         break;
 584                 case ENXIO:
 585                         db_printf("no dump device specified.\n");
 586                         break;
 587                 default:
 588                         db_printf("unknown error (error=%d).\n", error);
 589                         break;
 590                 }
 591         }
 592 }
 593
 594 /*
 595  * Call random function:
 596  * !expr(arg,arg,arg)
 597  */
 598
 599 /* The generic implementation supports a maximum of 10 arguments. */
 600 typedef db_expr_t __db_f(db_expr_t, db_expr_t, db_expr_t, db_expr_t,
 601     db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t);
 602
 603 static __inline int
 604 db_fncall_generic(db_expr_t addr, db_expr_t *rv, int nargs, db_expr_t args[])
 605 {
 606         __db_f *f = (__db_f *)addr;
 607
 608         if (nargs > 10) {
 609                 db_printf("Too many arguments (max 10)\n");
 610                 return (0);
 611         }
 612         *rv = (*f)(args[0], args[1], args[2], args[3], args[4], args[5],
 613             args[6], args[7], args[8], args[9]);
 614         return (1);
 615 }
 616
 617 static void
 618 db_fncall(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 619 {
 620         db_expr_t       fn_addr;
 621         db_expr_t       args[DB_MAXARGS];
 622         int             nargs = 0;
 623         db_expr_t       retval;
 624         int             t;
 625
 626         if (!db_expression(&fn_addr)) {
 627             db_printf("Bad function\n");
 628             db_flush_lex();
 629             return;
 630         }
 631
 632         t = db_read_token();
 633         if (t == tLPAREN) {
 634             if (db_expression(&args[0])) {
 635                 nargs++;
 636                 while ((t = db_read_token()) == tCOMMA) {
 637                     if (nargs == DB_MAXARGS) {
 638                         db_printf("Too many arguments (max %d)\n", DB_MAXARGS);
 639                         db_flush_lex();
 640                         return;
 641                     }
 642                     if (!db_expression(&args[nargs])) {
 643                         db_printf("Argument missing\n");
 644                         db_flush_lex();
 645                         return;
 646                     }
 647                     nargs++;
 648                 }
 649                 db_unread_token(t);
 650             }
 651             if (db_read_token() != tRPAREN) {
 652                 db_printf("Mismatched parens\n");
 653                 db_flush_lex();
 654                 return;
 655             }
 656         }
 657         db_skip_to_eol();
 658         db_disable_pager();
 659
 660         if (DB_CALL(fn_addr, &retval, nargs, args))
 661                 db_printf("= %#lr\n", (long)retval);
 662 }
 663
 664 static void
 665 db_halt(db_expr_t dummy, bool dummy2, db_expr_t dummy3, char *dummy4)
 666 {
 667
 668         cpu_halt();
 669 }
 670
 671 static void
 672 db_kill(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 673 {
 674         db_expr_t old_radix, pid, sig;
 675         struct proc *p;
 676
 677 #define DB_ERROR(f)     do { db_printf f; db_flush_lex(); goto out; } while (0)
 678
 679         /*
 680          * PIDs and signal numbers are typically represented in base
 681          * 10, so make that the default here.  It can, of course, be
 682          * overridden by specifying a prefix.
 683          */
 684         old_radix = db_radix;
 685         db_radix = 10;
 686         /* Retrieve arguments. */
 687         if (!db_expression(&sig))
 688                 DB_ERROR(("Missing signal number\n"));
 689         if (!db_expression(&pid))
 690                 DB_ERROR(("Missing process ID\n"));
 691         db_skip_to_eol();
 692         if (!_SIG_VALID(sig))
 693                 DB_ERROR(("Signal number out of range\n"));
 694
 695         /*
 696          * Find the process in question.  allproc_lock is not needed
 697          * since we're in DDB.
 698          */
 699         /* sx_slock(&allproc_lock); */
 700         FOREACH_PROC_IN_SYSTEM(p)
 701             if (p->p_pid == pid)
 702                     break;
 703         /* sx_sunlock(&allproc_lock); */
 704         if (p == NULL)
 705                 DB_ERROR(("Can't find process with pid %ld\n", (long) pid));
 706
 707         /* If it's already locked, bail; otherwise, do the deed. */
 708         if (PROC_TRYLOCK(p) == 0)
 709                 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid));
 710         else {
 711                 pksignal(p, sig, NULL);
 712                 PROC_UNLOCK(p);
 713         }
 714
 715 out:
 716         db_radix = old_radix;
 717 #undef DB_ERROR
 718 }
 719
 720 /*
 721  * Reboot.  In case there is an additional argument, take it as delay in
 722  * seconds.  Default to 15s if we cannot parse it and make sure we will
 723  * never wait longer than 1 week.  Some code is similar to
 724  * kern_shutdown.c:shutdown_panic().
 725  */
 726 #ifndef DB_RESET_MAXDELAY
 727 #define DB_RESET_MAXDELAY       (3600 * 24 * 7)
 728 #endif
 729
 730 static void
 731 db_reset(db_expr_t addr, bool have_addr, db_expr_t count __unused,
 732     char *modif __unused)
 733 {
 734         int delay, loop;
 735
 736         if (have_addr) {
 737                 delay = (int)db_hex2dec(addr);
 738
 739                 /* If we parse to fail, use 15s. */
 740                 if (delay == -1)
 741                         delay = 15;
 742
 743                 /* Cap at one week. */
 744                 if ((uintmax_t)delay > (uintmax_t)DB_RESET_MAXDELAY)
 745                         delay = DB_RESET_MAXDELAY;
 746
 747                 db_printf("Automatic reboot in %d seconds - "
 748                     "press a key on the console to abort\n", delay);
 749                 for (loop = delay * 10; loop > 0; --loop) {
 750                         DELAY(1000 * 100); /* 1/10th second */
 751                         /* Did user type a key? */
 752                         if (cncheckc() != -1)
 753                                 return;
 754                 }
 755         }
 756
 757         cpu_reset();
 758 }
 759
 760 static void
 761 db_watchdog(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 762 {
 763         db_expr_t old_radix, tout;
 764         int err, i;
 765
 766         old_radix = db_radix;
 767         db_radix = 10;
 768         err = db_expression(&tout);
 769         db_skip_to_eol();
 770         db_radix = old_radix;
 771
 772         /* If no argument is provided the watchdog will just be disabled. */
 773         if (err == 0) {
 774                 db_printf("No argument provided, disabling watchdog\n");
 775                 tout = 0;
 776         } else if ((tout & WD_INTERVAL) == WD_TO_NEVER) {
 777                 db_error("Out of range watchdog interval\n");
 778                 return;
 779         }
 780         EVENTHANDLER_INVOKE(watchdog_list, tout, &i);
 781 }
 782
 783 static void
 784 db_gdb(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
 785 {
 786
 787         if (kdb_dbbe_select("gdb") != 0) {
 788                 db_printf("The remote GDB backend could not be selected.\n");
 789                 return;
 790         }
 791         /*
 792          * Mark that we are done in the debugger.  kdb_trap()
 793          * should re-enter with the new backend.
 794          */
 795         db_cmd_loop_done = 1;
 796         db_printf("(ctrl-c will return control to ddb)\n");
 797 }
 798
 799 static void
 800 db_stack_trace(db_expr_t tid, bool hastid, db_expr_t count, char *modif)
 801 {
 802         struct thread *td;
 803         db_expr_t radix;
 804         pid_t pid;
 805         int t;
 806
 807         /*
 808          * We parse our own arguments. We don't like the default radix.
 809          */
 810         radix = db_radix;
 811         db_radix = 10;
 812         hastid = db_expression(&tid);
 813         t = db_read_token();
 814         if (t == tCOMMA) {
 815                 if (!db_expression(&count)) {
 816                         db_printf("Count missing\n");
 817                         db_flush_lex();
 818                         db_radix = radix;
 819                         return;
 820                 }
 821         } else {
 822                 db_unread_token(t);
 823                 count = -1;
 824         }
 825         db_skip_to_eol();
 826         db_radix = radix;
 827
 828         if (hastid) {
 829                 td = kdb_thr_lookup((lwpid_t)tid);
 830                 if (td == NULL)
 831                         td = kdb_thr_from_pid((pid_t)tid);
 832                 if (td == NULL) {
 833                         db_printf("Thread %d not found\n", (int)tid);
 834                         return;
 835                 }
 836         } else
 837                 td = kdb_thread;
 838         if (td->td_proc != NULL)
 839                 pid = td->td_proc->p_pid;
 840         else
 841                 pid = -1;
 842         db_printf("Tracing pid %d tid %ld td %p\n", pid, (long)td->td_tid, td);
 843         if (td->td_proc != NULL && (td->td_proc->p_flag & P_INMEM) == 0)
 844                 db_printf("--- swapped out\n");
 845         else
 846                 db_trace_thread(td, count);
 847 }
 848
 849 static void
 850 _db_stack_trace_all(bool active_only)
 851 {
 852         struct thread *td;
 853         jmp_buf jb;
 854         void *prev_jb;
 855
 856         for (td = kdb_thr_first(); td != NULL; td = kdb_thr_next(td)) {
 857                 prev_jb = kdb_jmpbuf(jb);
 858                 if (setjmp(jb) == 0) {
 859                         if (td->td_state == TDS_RUNNING)
 860                                 db_printf("\nTracing command %s pid %d"
 861                                     " tid %ld td %p (CPU %d)\n",
 862                                     td->td_proc->p_comm, td->td_proc->p_pid,
 863                                     (long)td->td_tid, td, td->td_oncpu);
 864                         else if (active_only)
 865                                 continue;
 866                         else
 867                                 db_printf("\nTracing command %s pid %d"
 868                                     " tid %ld td %p\n", td->td_proc->p_comm,
 869                                     td->td_proc->p_pid, (long)td->td_tid, td);
 870                         if (td->td_proc->p_flag & P_INMEM)
 871                                 db_trace_thread(td, -1);
 872                         else
 873                                 db_printf("--- swapped out\n");
 874                         if (db_pager_quit) {
 875                                 kdb_jmpbuf(prev_jb);
 876                                 return;
 877                         }
 878                 }
 879                 kdb_jmpbuf(prev_jb);
 880         }
 881 }
 882
 883 static void
 884 db_stack_trace_active(db_expr_t dummy, bool dummy2, db_expr_t dummy3,
 885     char *dummy4)
 886 {
 887
 888         _db_stack_trace_all(true);
 889 }
 890
 891 static void
 892 db_stack_trace_all(db_expr_t dummy, bool dummy2, db_expr_t dummy3,
 893     char *dummy4)
 894 {
 895
 896         _db_stack_trace_all(false);
 897 }
 898
 899 /*
 900  * Take the parsed expression value from the command line that was parsed
 901  * as a hexadecimal value and convert it as if the expression was parsed
 902  * as a decimal value.  Returns -1 if the expression was not a valid
 903  * decimal value.
 904  */
 905 db_expr_t
 906 db_hex2dec(db_expr_t expr)
 907 {
 908         uintptr_t x, y;
 909         db_expr_t val;
 910
 911         y = 1;
 912         val = 0;
 913         x = expr;
 914         while (x != 0) {
 915                 if (x % 16 > 9)
 916                         return (-1);
 917                 val += (x % 16) * (y);
 918                 x >>= 4;
 919                 y *= 10;
 920         }
 921         return (val);
 922 }