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/watchdog.h>
  48
  49 #include <ddb/ddb.h>
  50 #include <ddb/db_command.h>
  51 #include <ddb/db_lex.h>
  52 #include <ddb/db_output.h>
  53
  54 #include <machine/cpu.h>
  55 #include <machine/setjmp.h>
  56
  57 /*
  58  * Exported global variables
  59  */
  60 boolean_t       db_cmd_loop_done;
  61 db_addr_t       db_dot;
  62 db_addr_t       db_last_addr;
  63 db_addr_t       db_prev;
  64 db_addr_t       db_next;
  65
  66 SET_DECLARE(db_cmd_set, struct command);
  67 SET_DECLARE(db_show_cmd_set, struct command);
  68
  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_all;
  76 static db_cmdfcn_t      db_watchdog;
  77
  78 /*
  79  * 'show' commands
  80  */
  81
  82 static struct command db_show_all_cmds[] = {
  83         { "procs",      db_ps,                  0,      0 },
  84         { (char *)0 }
  85 };
  86
  87 static struct command db_show_cmds[] = {
  88         { "all",        0,                      0,      db_show_all_cmds },
  89         { "registers",  db_show_regs,           0,      0 },
  90         { "breaks",     db_listbreak_cmd,       0,      0 },
  91         { "threads",    db_show_threads,        0,      0 },
  92         { (char *)0, }
  93 };
  94
  95 static struct command db_command_table[] = {
  96         { "print",      db_print_cmd,           0,      0 },
  97         { "p",          db_print_cmd,           0,      0 },
  98         { "examine",    db_examine_cmd,         CS_SET_DOT, 0 },
  99         { "x",          db_examine_cmd,         CS_SET_DOT, 0 },
 100         { "search",     db_search_cmd,          CS_OWN|CS_SET_DOT, 0 },
 101         { "set",        db_set_cmd,             CS_OWN, 0 },
 102         { "write",      db_write_cmd,           CS_MORE|CS_SET_DOT, 0 },
 103         { "w",          db_write_cmd,           CS_MORE|CS_SET_DOT, 0 },
 104         { "delete",     db_delete_cmd,          0,      0 },
 105         { "d",          db_delete_cmd,          0,      0 },
 106         { "break",      db_breakpoint_cmd,      0,      0 },
 107         { "dwatch",     db_deletewatch_cmd,     0,      0 },
 108         { "watch",      db_watchpoint_cmd,      CS_MORE,0 },
 109         { "dhwatch",    db_deletehwatch_cmd,    0,      0 },
 110         { "hwatch",     db_hwatchpoint_cmd,     0,      0 },
 111         { "step",       db_single_step_cmd,     0,      0 },
 112         { "s",          db_single_step_cmd,     0,      0 },
 113         { "continue",   db_continue_cmd,        0,      0 },
 114         { "c",          db_continue_cmd,        0,      0 },
 115         { "until",      db_trace_until_call_cmd,0,      0 },
 116         { "next",       db_trace_until_matching_cmd,0,  0 },
 117         { "match",      db_trace_until_matching_cmd,0,  0 },
 118         { "trace",      db_stack_trace,         CS_OWN, 0 },
 119         { "alltrace",   db_stack_trace_all,     0,      0 },
 120         { "where",      db_stack_trace,         CS_OWN, 0 },
 121         { "bt",         db_stack_trace,         CS_OWN, 0 },
 122         { "call",       db_fncall,              CS_OWN, 0 },
 123         { "show",       0,                      0,      db_show_cmds },
 124         { "ps",         db_ps,                  0,      0 },
 125         { "gdb",        db_gdb,                 0,      0 },
 126         { "halt",       db_halt,                0,      0 },
 127         { "reboot",     db_reset,               0,      0 },
 128         { "reset",      db_reset,               0,      0 },
 129         { "kill",       db_kill,                CS_OWN, 0 },
 130         { "watchdog",   db_watchdog,            0,      0 },
 131         { "thread",     db_set_thread,          CS_OWN, 0 },
 132         { (char *)0, }
 133 };
 134
 135 static struct command   *db_last_command = 0;
 136
 137
 138 /*
 139  * if 'ed' style: 'dot' is set at start of last item printed,
 140  * and '+' points to next line.
 141  * Otherwise: 'dot' points to next item, '..' points to last.
 142  */
 143 static boolean_t        db_ed_style = TRUE;
 144
 145 /*
 146  * Utility routine - discard tokens through end-of-line.
 147  */
 148 void
 149 db_skip_to_eol()
 150 {
 151         int     t;
 152         do {
 153             t = db_read_token();
 154         } while (t != tEOL);
 155 }
 156
 157 /*
 158  * Results of command search.
 159  */
 160 #define CMD_UNIQUE      0
 161 #define CMD_FOUND       1
 162 #define CMD_NONE        2
 163 #define CMD_AMBIGUOUS   3
 164 #define CMD_HELP        4
 165
 166 static void     db_cmd_list(struct command *table, struct command **aux_tablep,
 167                     struct command **aux_tablep_end);
 168 static int      db_cmd_search(char *name, struct command *table,
 169                     struct command **aux_tablep,
 170                     struct command **aux_tablep_end, struct command **cmdp);
 171 static void     db_command(struct command **last_cmdp,
 172                     struct command *cmd_table, struct command **aux_cmd_tablep,
 173                     struct command **aux_cmd_tablep_end);
 174
 175 /*
 176  * Search for command prefix.
 177  */
 178 static int
 179 db_cmd_search(name, table, aux_tablep, aux_tablep_end, cmdp)
 180         char *          name;
 181         struct command  *table;
 182         struct command  **aux_tablep;
 183         struct command  **aux_tablep_end;
 184         struct command  **cmdp; /* out */
 185 {
 186         struct command  *cmd;
 187         struct command  **aux_cmdp;
 188         int             result = CMD_NONE;
 189
 190         for (cmd = table; cmd->name != 0; cmd++) {
 191             register char *lp;
 192             register char *rp;
 193             register int  c;
 194
 195             lp = name;
 196             rp = cmd->name;
 197             while ((c = *lp) == *rp) {
 198                 if (c == 0) {
 199                     /* complete match */
 200                     *cmdp = cmd;
 201                     return (CMD_UNIQUE);
 202                 }
 203                 lp++;
 204                 rp++;
 205             }
 206             if (c == 0) {
 207                 /* end of name, not end of command -
 208                    partial match */
 209                 if (result == CMD_FOUND) {
 210                     result = CMD_AMBIGUOUS;
 211                     /* but keep looking for a full match -
 212                        this lets us match single letters */
 213                 }
 214                 else {
 215                     *cmdp = cmd;
 216                     result = CMD_FOUND;
 217                 }
 218             }
 219         }
 220         if (result == CMD_NONE && aux_tablep != 0)
 221             /* XXX repeat too much code. */
 222             for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) {
 223                 register char *lp;
 224                 register char *rp;
 225                 register int  c;
 226
 227                 lp = name;
 228                 rp = (*aux_cmdp)->name;
 229                 while ((c = *lp) == *rp) {
 230                     if (c == 0) {
 231                         /* complete match */
 232                         *cmdp = *aux_cmdp;
 233                         return (CMD_UNIQUE);
 234                     }
 235                     lp++;
 236                     rp++;
 237                 }
 238                 if (c == 0) {
 239                     /* end of name, not end of command -
 240                        partial match */
 241                     if (result == CMD_FOUND) {
 242                         result = CMD_AMBIGUOUS;
 243                         /* but keep looking for a full match -
 244                            this lets us match single letters */
 245                     }
 246                     else {
 247                         *cmdp = *aux_cmdp;
 248                         result = CMD_FOUND;
 249                     }
 250                 }
 251             }
 252         if (result == CMD_NONE) {
 253             /* check for 'help' */
 254                 if (name[0] == 'h' && name[1] == 'e'
 255                     && name[2] == 'l' && name[3] == 'p')
 256                         result = CMD_HELP;
 257         }
 258         return (result);
 259 }
 260
 261 static void
 262 db_cmd_list(table, aux_tablep, aux_tablep_end)
 263         struct command *table;
 264         struct command **aux_tablep;
 265         struct command **aux_tablep_end;
 266 {
 267         register struct command *cmd;
 268         register struct command **aux_cmdp;
 269
 270         for (cmd = table; cmd->name != 0; cmd++) {
 271             db_printf("%-12s", cmd->name);
 272             db_end_line();
 273         }
 274         if (aux_tablep == 0)
 275             return;
 276         for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) {
 277             db_printf("%-12s", (*aux_cmdp)->name);
 278             db_end_line();
 279         }
 280 }
 281
 282 static void
 283 db_command(last_cmdp, cmd_table, aux_cmd_tablep, aux_cmd_tablep_end)
 284         struct command  **last_cmdp;    /* IN_OUT */
 285         struct command  *cmd_table;
 286         struct command  **aux_cmd_tablep;
 287         struct command  **aux_cmd_tablep_end;
 288 {
 289         struct command  *cmd;
 290         int             t;
 291         char            modif[TOK_STRING_SIZE];
 292         db_expr_t       addr, count;
 293         boolean_t       have_addr = FALSE;
 294         int             result;
 295
 296         t = db_read_token();
 297         if (t == tEOL) {
 298             /* empty line repeats last command, at 'next' */
 299             cmd = *last_cmdp;
 300             addr = (db_expr_t)db_next;
 301             have_addr = FALSE;
 302             count = 1;
 303             modif[0] = '\0';
 304         }
 305         else if (t == tEXCL) {
 306             db_fncall((db_expr_t)0, (boolean_t)0, (db_expr_t)0, (char *)0);
 307             return;
 308         }
 309         else if (t != tIDENT) {
 310             db_printf("?\n");
 311             db_flush_lex();
 312             return;
 313         }
 314         else {
 315             /*
 316              * Search for command
 317              */
 318             while (cmd_table) {
 319                 result = db_cmd_search(db_tok_string,
 320                                        cmd_table,
 321                                        aux_cmd_tablep,
 322                                        aux_cmd_tablep_end,
 323                                        &cmd);
 324                 switch (result) {
 325                     case CMD_NONE:
 326                         db_printf("No such command\n");
 327                         db_flush_lex();
 328                         return;
 329                     case CMD_AMBIGUOUS:
 330                         db_printf("Ambiguous\n");
 331                         db_flush_lex();
 332                         return;
 333                     case CMD_HELP:
 334                         db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end);
 335                         db_flush_lex();
 336                         return;
 337                     default:
 338                         break;
 339                 }
 340                 if ((cmd_table = cmd->more) != 0) {
 341                     /* XXX usually no more aux's. */
 342                     aux_cmd_tablep = 0;
 343                     if (cmd_table == db_show_cmds) {
 344                         aux_cmd_tablep = SET_BEGIN(db_show_cmd_set);
 345                         aux_cmd_tablep_end = SET_LIMIT(db_show_cmd_set);
 346                     }
 347
 348                     t = db_read_token();
 349                     if (t != tIDENT) {
 350                         db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end);
 351                         db_flush_lex();
 352                         return;
 353                     }
 354                 }
 355             }
 356
 357             if ((cmd->flag & CS_OWN) == 0) {
 358                 /*
 359                  * Standard syntax:
 360                  * command [/modifier] [addr] [,count]
 361                  */
 362                 t = db_read_token();
 363                 if (t == tSLASH) {
 364                     t = db_read_token();
 365                     if (t != tIDENT) {
 366                         db_printf("Bad modifier\n");
 367                         db_flush_lex();
 368                         return;
 369                     }
 370                     db_strcpy(modif, db_tok_string);
 371                 }
 372                 else {
 373                     db_unread_token(t);
 374                     modif[0] = '\0';
 375                 }
 376
 377                 if (db_expression(&addr)) {
 378                     db_dot = (db_addr_t) addr;
 379                     db_last_addr = db_dot;
 380                     have_addr = TRUE;
 381                 }
 382                 else {
 383                     addr = (db_expr_t) db_dot;
 384                     have_addr = FALSE;
 385                 }
 386                 t = db_read_token();
 387                 if (t == tCOMMA) {
 388                     if (!db_expression(&count)) {
 389                         db_printf("Count missing\n");
 390                         db_flush_lex();
 391                         return;
 392                     }
 393                 }
 394                 else {
 395                     db_unread_token(t);
 396                     count = -1;
 397                 }
 398                 if ((cmd->flag & CS_MORE) == 0) {
 399                     db_skip_to_eol();
 400                 }
 401             }
 402         }
 403         *last_cmdp = cmd;
 404         if (cmd != 0) {
 405             /*
 406              * Execute the command.
 407              */
 408             (*cmd->fcn)(addr, have_addr, count, modif);
 409             db_setup_paging(NULL, NULL, -1);
 410
 411             if (cmd->flag & CS_SET_DOT) {
 412                 /*
 413                  * If command changes dot, set dot to
 414                  * previous address displayed (if 'ed' style).
 415                  */
 416                 if (db_ed_style) {
 417                     db_dot = db_prev;
 418                 }
 419                 else {
 420                     db_dot = db_next;
 421                 }
 422             }
 423             else {
 424                 /*
 425                  * If command does not change dot,
 426                  * set 'next' location to be the same.
 427                  */
 428                 db_next = db_dot;
 429             }
 430         }
 431 }
 432
 433 /*
 434  * At least one non-optional command must be implemented using
 435  * DB_COMMAND() so that db_cmd_set gets created.  Here is one.
 436  */
 437 DB_COMMAND(panic, db_panic)
 438 {
 439         panic("from debugger");
 440 }
 441
 442 void
 443 db_command_loop()
 444 {
 445         /*
 446          * Initialize 'prev' and 'next' to dot.
 447          */
 448         db_prev = db_dot;
 449         db_next = db_dot;
 450
 451         db_cmd_loop_done = 0;
 452         while (!db_cmd_loop_done) {
 453             if (db_print_position() != 0)
 454                 db_printf("\n");
 455
 456             db_printf("db> ");
 457             (void) db_read_line();
 458
 459             db_command(&db_last_command, db_command_table,
 460                        SET_BEGIN(db_cmd_set), SET_LIMIT(db_cmd_set));
 461         }
 462 }
 463
 464 void
 465 db_error(s)
 466         const char *s;
 467 {
 468         if (s)
 469             db_printf("%s", s);
 470         db_flush_lex();
 471         kdb_reenter();
 472 }
 473
 474
 475 /*
 476  * Call random function:
 477  * !expr(arg,arg,arg)
 478  */
 479
 480 /* The generic implementation supports a maximum of 10 arguments. */
 481 typedef db_expr_t __db_f(db_expr_t, db_expr_t, db_expr_t, db_expr_t,
 482     db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t);
 483
 484 static __inline int
 485 db_fncall_generic(db_expr_t addr, db_expr_t *rv, int nargs, db_expr_t args[])
 486 {
 487         __db_f *f = (__db_f *)addr;
 488
 489         if (nargs > 10) {
 490                 db_printf("Too many arguments (max 10)\n");
 491                 return (0);
 492         }
 493         *rv = (*f)(args[0], args[1], args[2], args[3], args[4], args[5],
 494             args[6], args[7], args[8], args[9]);
 495         return (1);
 496 }
 497
 498 static void
 499 db_fncall(dummy1, dummy2, dummy3, dummy4)
 500         db_expr_t       dummy1;
 501         boolean_t       dummy2;
 502         db_expr_t       dummy3;
 503         char *          dummy4;
 504 {
 505         db_expr_t       fn_addr;
 506         db_expr_t       args[DB_MAXARGS];
 507         int             nargs = 0;
 508         db_expr_t       retval;
 509         int             t;
 510
 511         if (!db_expression(&fn_addr)) {
 512             db_printf("Bad function\n");
 513             db_flush_lex();
 514             return;
 515         }
 516
 517         t = db_read_token();
 518         if (t == tLPAREN) {
 519             if (db_expression(&args[0])) {
 520                 nargs++;
 521                 while ((t = db_read_token()) == tCOMMA) {
 522                     if (nargs == DB_MAXARGS) {
 523                         db_printf("Too many arguments (max %d)\n", DB_MAXARGS);
 524                         db_flush_lex();
 525                         return;
 526                     }
 527                     if (!db_expression(&args[nargs])) {
 528                         db_printf("Argument missing\n");
 529                         db_flush_lex();
 530                         return;
 531                     }
 532                     nargs++;
 533                 }
 534                 db_unread_token(t);
 535             }
 536             if (db_read_token() != tRPAREN) {
 537                 db_printf("?\n");
 538                 db_flush_lex();
 539                 return;
 540             }
 541         }
 542         db_skip_to_eol();
 543
 544         if (DB_CALL(fn_addr, &retval, nargs, args))
 545                 db_printf("= %#lr\n", (long)retval);
 546 }
 547
 548 static void
 549 db_halt(db_expr_t dummy, boolean_t dummy2, db_expr_t dummy3, char *dummy4)
 550 {
 551
 552         cpu_halt();
 553 }
 554
 555 static void
 556 db_kill(dummy1, dummy2, dummy3, dummy4)
 557         db_expr_t       dummy1;
 558         boolean_t       dummy2;
 559         db_expr_t       dummy3;
 560         char *          dummy4;
 561 {
 562         db_expr_t old_radix, pid, sig;
 563         struct proc *p;
 564
 565 #define DB_ERROR(f)     do { db_printf f; db_flush_lex(); goto out; } while (0)
 566
 567         /*
 568          * PIDs and signal numbers are typically represented in base
 569          * 10, so make that the default here.  It can, of course, be
 570          * overridden by specifying a prefix.
 571          */
 572         old_radix = db_radix;
 573         db_radix = 10;
 574         /* Retrieve arguments. */
 575         if (!db_expression(&sig))
 576                 DB_ERROR(("Missing signal number\n"));
 577         if (!db_expression(&pid))
 578                 DB_ERROR(("Missing process ID\n"));
 579         db_skip_to_eol();
 580         if (sig < 1 || sig > _SIG_MAXSIG)
 581                 DB_ERROR(("Signal number out of range\n"));
 582
 583         /*
 584          * Find the process in question.  allproc_lock is not needed
 585          * since we're in DDB.
 586          */
 587         /* sx_slock(&allproc_lock); */
 588         LIST_FOREACH(p, &allproc, p_list)
 589             if (p->p_pid == pid)
 590                     break;
 591         /* sx_sunlock(&allproc_lock); */
 592         if (p == NULL)
 593                 DB_ERROR(("Can't find process with pid %ld\n", (long) pid));
 594
 595         /* If it's already locked, bail; otherwise, do the deed. */
 596         if (PROC_TRYLOCK(p) == 0)
 597                 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid));
 598         else {
 599                 psignal(p, sig);
 600                 PROC_UNLOCK(p);
 601         }
 602
 603 out:
 604         db_radix = old_radix;
 605 #undef DB_ERROR
 606 }
 607
 608 static void
 609 db_reset(dummy1, dummy2, dummy3, dummy4)
 610         db_expr_t       dummy1;
 611         boolean_t       dummy2;
 612         db_expr_t       dummy3;
 613         char *          dummy4;
 614 {
 615
 616         cpu_reset();
 617 }
 618
 619 static void
 620 db_watchdog(dummy1, dummy2, dummy3, dummy4)
 621         db_expr_t       dummy1;
 622         boolean_t       dummy2;
 623         db_expr_t       dummy3;
 624         char *          dummy4;
 625 {
 626         int i;
 627
 628         /*
 629          * XXX: It might make sense to be able to set the watchdog to a
 630          * XXX: timeout here so that failure or hang as a result of subsequent
 631          * XXX: ddb commands could be recovered by a reset.
 632          */
 633
 634         EVENTHANDLER_INVOKE(watchdog_list, 0, &i);
 635 }
 636
 637 static void
 638 db_gdb(db_expr_t dummy1, boolean_t dummy2, db_expr_t dummy3, char *dummy4)
 639 {
 640
 641         if (kdb_dbbe_select("gdb") != 0)
 642                 db_printf("The remote GDB backend could not be selected.\n");
 643         else
 644                 db_printf("Step to enter the remote GDB backend.\n");
 645 }
 646
 647 static void
 648 db_stack_trace(db_expr_t tid, boolean_t hastid, db_expr_t count, char *modif)
 649 {
 650         struct thread *td;
 651         db_expr_t radix;
 652         pid_t pid;
 653         int t;
 654
 655         /*
 656          * We parse our own arguments. We don't like the default radix.
 657          */
 658         radix = db_radix;
 659         db_radix = 10;
 660         hastid = db_expression(&tid);
 661         t = db_read_token();
 662         if (t == tCOMMA) {
 663                 if (!db_expression(&count)) {
 664                         db_printf("Count missing\n");
 665                         db_flush_lex();
 666                         return;
 667                 }
 668         } else {
 669                 db_unread_token(t);
 670                 count = -1;
 671         }
 672         db_skip_to_eol();
 673         db_radix = radix;
 674
 675         if (hastid) {
 676                 td = kdb_thr_lookup((lwpid_t)tid);
 677                 if (td == NULL)
 678                         td = kdb_thr_from_pid((pid_t)tid);
 679                 if (td == NULL) {
 680                         db_printf("Thread %d not found\n", (int)tid);
 681                         return;
 682                 }
 683         } else
 684                 td = kdb_thread;
 685         if (td->td_proc != NULL)
 686                 pid = td->td_proc->p_pid;
 687         else
 688                 pid = -1;
 689         db_printf("Tracing pid %d tid %ld td %p\n", pid, (long)td->td_tid, td);
 690         db_trace_thread(td, count);
 691 }
 692
 693 static void
 694 db_stack_trace_all(db_expr_t dummy, boolean_t dummy2, db_expr_t dummy3,
 695     char *dummy4)
 696 {
 697         struct proc *p;
 698         struct thread *td;
 699
 700         for (p = LIST_FIRST(&allproc); p != NULL; p = LIST_NEXT(p, p_list)) {
 701                 FOREACH_THREAD_IN_PROC(p, td) {
 702                         db_printf("\nTracing command %s pid %d tid %ld td %p\n",
 703                             p->p_comm, p->p_pid, (long)td->td_tid, td);
 704                         db_trace_thread(td, -1);
 705                 }
 706         }
 707 }