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_kill; 72 static db_cmdfcn_t db_reset; 73 static db_cmdfcn_t db_stack_trace; 74 static db_cmdfcn_t db_stack_trace_all; 75 static db_cmdfcn_t db_watchdog; 76 77 /* 78 * 'show' commands 79 */ 80 81 static struct command db_show_all_cmds[] = { 82 { "procs", db_ps, 0, 0 }, 83 { (char *)0 } 84 }; 85 86 static struct command db_show_cmds[] = { 87 { "all", 0, 0, db_show_all_cmds }, 88 { "registers", db_show_regs, 0, 0 }, 89 { "breaks", db_listbreak_cmd, 0, 0 }, 90 { "threads", db_show_threads, 0, 0 }, 91 { (char *)0, } 92 }; 93 94 static struct command db_command_table[] = { 95 { "print", db_print_cmd, 0, 0 }, 96 { "p", db_print_cmd, 0, 0 }, 97 { "examine", db_examine_cmd, CS_SET_DOT, 0 }, 98 { "x", db_examine_cmd, CS_SET_DOT, 0 }, 99 { "search", db_search_cmd, CS_OWN|CS_SET_DOT, 0 }, 100 { "set", db_set_cmd, CS_OWN, 0 }, 101 { "write", db_write_cmd, CS_MORE|CS_SET_DOT, 0 }, 102 { "w", db_write_cmd, CS_MORE|CS_SET_DOT, 0 }, 103 { "delete", db_delete_cmd, 0, 0 }, 104 { "d", db_delete_cmd, 0, 0 }, 105 { "break", db_breakpoint_cmd, 0, 0 }, 106 { "dwatch", db_deletewatch_cmd, 0, 0 }, 107 { "watch", db_watchpoint_cmd, CS_MORE,0 }, 108 { "dhwatch", db_deletehwatch_cmd, 0, 0 }, 109 { "hwatch", db_hwatchpoint_cmd, 0, 0 }, 110 { "step", db_single_step_cmd, 0, 0 }, 111 { "s", db_single_step_cmd, 0, 0 }, 112 { "continue", db_continue_cmd, 0, 0 }, 113 { "c", db_continue_cmd, 0, 0 }, 114 { "until", db_trace_until_call_cmd,0, 0 }, 115 { "next", db_trace_until_matching_cmd,0, 0 }, 116 { "match", db_trace_until_matching_cmd,0, 0 }, 117 { "trace", db_stack_trace, CS_OWN, 0 }, 118 { "alltrace", db_stack_trace_all, 0, 0 }, 119 { "where", db_stack_trace, CS_OWN, 0 }, 120 { "bt", db_stack_trace, CS_OWN, 0 }, 121 { "call", db_fncall, CS_OWN, 0 }, 122 { "show", 0, 0, db_show_cmds }, 123 { "ps", db_ps, 0, 0 }, 124 { "gdb", db_gdb, 0, 0 }, 125 { "reset", db_reset, 0, 0 }, 126 { "kill", db_kill, CS_OWN, 0 }, 127 { "watchdog", db_watchdog, 0, 0 }, 128 { "thread", db_set_thread, CS_OWN, 0 }, 129 { (char *)0, } 130 }; 131 132 static struct command *db_last_command = 0; 133 134 /* 135 * if 'ed' style: 'dot' is set at start of last item printed, 136 * and '+' points to next line. 137 * Otherwise: 'dot' points to next item, '..' points to last. 138 */ 139 static boolean_t db_ed_style = TRUE; 140 141 /* 142 * Utility routine - discard tokens through end-of-line. 143 */ 144 void 145 db_skip_to_eol() 146 { 147 int t; 148 do { 149 t = db_read_token(); 150 } while (t != tEOL); 151 } 152 153 /* 154 * Results of command search. 155 */ 156 #define CMD_UNIQUE 0 157 #define CMD_FOUND 1 158 #define CMD_NONE 2 159 #define CMD_AMBIGUOUS 3 160 #define CMD_HELP 4 161 162 static void db_cmd_list(struct command *table, struct command **aux_tablep, 163 struct command **aux_tablep_end); 164 static int db_cmd_search(char *name, struct command *table, 165 struct command **aux_tablep, 166 struct command **aux_tablep_end, struct command **cmdp); 167 static void db_command(struct command **last_cmdp, 168 struct command *cmd_table, struct command **aux_cmd_tablep, 169 struct command **aux_cmd_tablep_end); 170 171 /* 172 * Search for command prefix. 173 */ 174 static int 175 db_cmd_search(name, table, aux_tablep, aux_tablep_end, cmdp) 176 char * name; 177 struct command *table; 178 struct command **aux_tablep; 179 struct command **aux_tablep_end; 180 struct command **cmdp; /* out */ 181 { 182 struct command *cmd; 183 struct command **aux_cmdp; 184 int result = CMD_NONE; 185 186 for (cmd = table; cmd->name != 0; cmd++) { 187 register char *lp; 188 register char *rp; 189 register int c; 190 191 lp = name; 192 rp = cmd->name; 193 while ((c = *lp) == *rp) { 194 if (c == 0) { 195 /* complete match */ 196 *cmdp = cmd; 197 return (CMD_UNIQUE); 198 } 199 lp++; 200 rp++; 201 } 202 if (c == 0) { 203 /* end of name, not end of command - 204 partial match */ 205 if (result == CMD_FOUND) { 206 result = CMD_AMBIGUOUS; 207 /* but keep looking for a full match - 208 this lets us match single letters */ 209 } 210 else { 211 *cmdp = cmd; 212 result = CMD_FOUND; 213 } 214 } 215 } 216 if (result == CMD_NONE && aux_tablep != 0) 217 /* XXX repeat too much code. */ 218 for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) { 219 register char *lp; 220 register char *rp; 221 register int c; 222 223 lp = name; 224 rp = (*aux_cmdp)->name; 225 while ((c = *lp) == *rp) { 226 if (c == 0) { 227 /* complete match */ 228 *cmdp = *aux_cmdp; 229 return (CMD_UNIQUE); 230 } 231 lp++; 232 rp++; 233 } 234 if (c == 0) { 235 /* end of name, not end of command - 236 partial match */ 237 if (result == CMD_FOUND) { 238 result = CMD_AMBIGUOUS; 239 /* but keep looking for a full match - 240 this lets us match single letters */ 241 } 242 else { 243 *cmdp = *aux_cmdp; 244 result = CMD_FOUND; 245 } 246 } 247 } 248 if (result == CMD_NONE) { 249 /* check for 'help' */ 250 if (name[0] == 'h' && name[1] == 'e' 251 && name[2] == 'l' && name[3] == 'p') 252 result = CMD_HELP; 253 } 254 return (result); 255 } 256 257 static void 258 db_cmd_list(table, aux_tablep, aux_tablep_end) 259 struct command *table; 260 struct command **aux_tablep; 261 struct command **aux_tablep_end; 262 { 263 register struct command *cmd; 264 register struct command **aux_cmdp; 265 266 for (cmd = table; cmd->name != 0; cmd++) { 267 db_printf("%-12s", cmd->name); 268 db_end_line(); 269 } 270 if (aux_tablep == 0) 271 return; 272 for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) { 273 db_printf("%-12s", (*aux_cmdp)->name); 274 db_end_line(); 275 } 276 } 277 278 static void 279 db_command(last_cmdp, cmd_table, aux_cmd_tablep, aux_cmd_tablep_end) 280 struct command **last_cmdp; /* IN_OUT */ 281 struct command *cmd_table; 282 struct command **aux_cmd_tablep; 283 struct command **aux_cmd_tablep_end; 284 { 285 struct command *cmd; 286 int t; 287 char modif[TOK_STRING_SIZE]; 288 db_expr_t addr, count; 289 boolean_t have_addr = FALSE; 290 int result; 291 292 t = db_read_token(); 293 if (t == tEOL) { 294 /* empty line repeats last command, at 'next' */ 295 cmd = *last_cmdp; 296 addr = (db_expr_t)db_next; 297 have_addr = FALSE; 298 count = 1; 299 modif[0] = '\0'; 300 } 301 else if (t == tEXCL) { 302 db_fncall((db_expr_t)0, (boolean_t)0, (db_expr_t)0, (char *)0); 303 return; 304 } 305 else if (t != tIDENT) { 306 db_printf("?\n"); 307 db_flush_lex(); 308 return; 309 } 310 else { 311 /* 312 * Search for command 313 */ 314 while (cmd_table) { 315 result = db_cmd_search(db_tok_string, 316 cmd_table, 317 aux_cmd_tablep, 318 aux_cmd_tablep_end, 319 &cmd); 320 switch (result) { 321 case CMD_NONE: 322 db_printf("No such command\n"); 323 db_flush_lex(); 324 return; 325 case CMD_AMBIGUOUS: 326 db_printf("Ambiguous\n"); 327 db_flush_lex(); 328 return; 329 case CMD_HELP: 330 db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end); 331 db_flush_lex(); 332 return; 333 default: 334 break; 335 } 336 if ((cmd_table = cmd->more) != 0) { 337 /* XXX usually no more aux's. */ 338 aux_cmd_tablep = 0; 339 if (cmd_table == db_show_cmds) { 340 aux_cmd_tablep = SET_BEGIN(db_show_cmd_set); 341 aux_cmd_tablep_end = SET_LIMIT(db_show_cmd_set); 342 } 343 344 t = db_read_token(); 345 if (t != tIDENT) { 346 db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end); 347 db_flush_lex(); 348 return; 349 } 350 } 351 } 352 353 if ((cmd->flag & CS_OWN) == 0) { 354 /* 355 * Standard syntax: 356 * command [/modifier] [addr] [,count] 357 */ 358 t = db_read_token(); 359 if (t == tSLASH) { 360 t = db_read_token(); 361 if (t != tIDENT) { 362 db_printf("Bad modifier\n"); 363 db_flush_lex(); 364 return; 365 } 366 db_strcpy(modif, db_tok_string); 367 } 368 else { 369 db_unread_token(t); 370 modif[0] = '\0'; 371 } 372 373 if (db_expression(&addr)) { 374 db_dot = (db_addr_t) addr; 375 db_last_addr = db_dot; 376 have_addr = TRUE; 377 } 378 else { 379 addr = (db_expr_t) db_dot; 380 have_addr = FALSE; 381 } 382 t = db_read_token(); 383 if (t == tCOMMA) { 384 if (!db_expression(&count)) { 385 db_printf("Count missing\n"); 386 db_flush_lex(); 387 return; 388 } 389 } 390 else { 391 db_unread_token(t); 392 count = -1; 393 } 394 if ((cmd->flag & CS_MORE) == 0) { 395 db_skip_to_eol(); 396 } 397 } 398 } 399 *last_cmdp = cmd; 400 if (cmd != 0) { 401 /* 402 * Execute the command. 403 */ 404 (*cmd->fcn)(addr, have_addr, count, modif); 405 db_setup_paging(NULL, NULL, -1); 406 407 if (cmd->flag & CS_SET_DOT) { 408 /* 409 * If command changes dot, set dot to 410 * previous address displayed (if 'ed' style). 411 */ 412 if (db_ed_style) { 413 db_dot = db_prev; 414 } 415 else { 416 db_dot = db_next; 417 } 418 } 419 else { 420 /* 421 * If command does not change dot, 422 * set 'next' location to be the same. 423 */ 424 db_next = db_dot; 425 } 426 } 427 } 428 429 /* 430 * At least one non-optional command must be implemented using 431 * DB_COMMAND() so that db_cmd_set gets created. Here is one. 432 */ 433 DB_COMMAND(panic, db_panic) 434 { 435 panic("from debugger"); 436 } 437 438 void 439 db_command_loop() 440 { 441 /* 442 * Initialize 'prev' and 'next' to dot. 443 */ 444 db_prev = db_dot; 445 db_next = db_dot; 446 447 db_cmd_loop_done = 0; 448 while (!db_cmd_loop_done) { 449 if (db_print_position() != 0) 450 db_printf("\n"); 451 452 db_printf("db> "); 453 (void) db_read_line(); 454 455 db_command(&db_last_command, db_command_table, 456 SET_BEGIN(db_cmd_set), SET_LIMIT(db_cmd_set)); 457 } 458 } 459 460 void 461 db_error(s) 462 const char *s; 463 { 464 if (s) 465 db_printf("%s", s); 466 db_flush_lex(); 467 kdb_reenter(); 468 } 469 470 471 /* 472 * Call random function: 473 * !expr(arg,arg,arg) 474 */ 475 476 /* The generic implementation supports a maximum of 10 arguments. */ 477 typedef db_expr_t __db_f(db_expr_t, db_expr_t, db_expr_t, db_expr_t, 478 db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t); 479 480 static __inline int 481 db_fncall_generic(db_expr_t addr, db_expr_t *rv, int nargs, db_expr_t args[]) 482 { 483 __db_f *f = (__db_f *)addr; 484 485 if (nargs > 10) { 486 db_printf("Too many arguments (max 10)\n"); 487 return (0); 488 } 489 *rv = (*f)(args[0], args[1], args[2], args[3], args[4], args[5], 490 args[6], args[7], args[8], args[9]); 491 return (1); 492 } 493 494 static void 495 db_fncall(dummy1, dummy2, dummy3, dummy4) 496 db_expr_t dummy1; 497 boolean_t dummy2; 498 db_expr_t dummy3; 499 char * dummy4; 500 { 501 db_expr_t fn_addr; 502 db_expr_t args[DB_MAXARGS]; 503 int nargs = 0; 504 db_expr_t retval; 505 int t; 506 507 if (!db_expression(&fn_addr)) { 508 db_printf("Bad function\n"); 509 db_flush_lex(); 510 return; 511 } 512 513 t = db_read_token(); 514 if (t == tLPAREN) { 515 if (db_expression(&args[0])) { 516 nargs++; 517 while ((t = db_read_token()) == tCOMMA) { 518 if (nargs == DB_MAXARGS) { 519 db_printf("Too many arguments (max %d)\n", DB_MAXARGS); 520 db_flush_lex(); 521 return; 522 } 523 if (!db_expression(&args[nargs])) { 524 db_printf("Argument missing\n"); 525 db_flush_lex(); 526 return; 527 } 528 nargs++; 529 } 530 db_unread_token(t); 531 } 532 if (db_read_token() != tRPAREN) { 533 db_printf("?\n"); 534 db_flush_lex(); 535 return; 536 } 537 } 538 db_skip_to_eol(); 539 540 if (DB_CALL(fn_addr, &retval, nargs, args)) 541 db_printf("= %#lr\n", (long)retval); 542 } 543 544 static void 545 db_kill(dummy1, dummy2, dummy3, dummy4) 546 db_expr_t dummy1; 547 boolean_t dummy2; 548 db_expr_t dummy3; 549 char * dummy4; 550 { 551 db_expr_t old_radix, pid, sig; 552 struct proc *p; 553 554 #define DB_ERROR(f) do { db_printf f; db_flush_lex(); goto out; } while (0) 555 556 /* 557 * PIDs and signal numbers are typically represented in base 558 * 10, so make that the default here. It can, of course, be 559 * overridden by specifying a prefix. 560 */ 561 old_radix = db_radix; 562 db_radix = 10; 563 /* Retrieve arguments. */ 564 if (!db_expression(&sig)) 565 DB_ERROR(("Missing signal number\n")); 566 if (!db_expression(&pid)) 567 DB_ERROR(("Missing process ID\n")); 568 db_skip_to_eol(); 569 if (sig < 0 || sig > _SIG_MAXSIG) 570 DB_ERROR(("Signal number out of range\n")); 571 572 /* 573 * Find the process in question. allproc_lock is not needed 574 * since we're in DDB. 575 */ 576 /* sx_slock(&allproc_lock); */ 577 LIST_FOREACH(p, &allproc, p_list) 578 if (p->p_pid == pid) 579 break; 580 /* sx_sunlock(&allproc_lock); */ 581 if (p == NULL) 582 DB_ERROR(("Can't find process with pid %ld\n", (long) pid)); 583 584 /* If it's already locked, bail; otherwise, do the deed. */ 585 if (PROC_TRYLOCK(p) == 0) 586 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid)); 587 else { 588 psignal(p, sig); 589 PROC_UNLOCK(p); 590 } 591 592 out: 593 db_radix = old_radix; 594 #undef DB_ERROR 595 } 596 597 static void 598 db_reset(dummy1, dummy2, dummy3, dummy4) 599 db_expr_t dummy1; 600 boolean_t dummy2; 601 db_expr_t dummy3; 602 char * dummy4; 603 { 604 605 cpu_reset(); 606 } 607 608 static void 609 db_watchdog(dummy1, dummy2, dummy3, dummy4) 610 db_expr_t dummy1; 611 boolean_t dummy2; 612 db_expr_t dummy3; 613 char * dummy4; 614 { 615 int i; 616 617 /* 618 * XXX: It might make sense to be able to set the watchdog to a 619 * XXX: timeout here so that failure or hang as a result of subsequent 620 * XXX: ddb commands could be recovered by a reset. 621 */ 622 623 EVENTHANDLER_INVOKE(watchdog_list, 0, &i); 624 } 625 626 static void 627 db_gdb(db_expr_t dummy1, boolean_t dummy2, db_expr_t dummy3, char *dummy4) 628 { 629 630 if (kdb_dbbe_select("gdb") != 0) 631 db_printf("The remote GDB backend could not be selected.\n"); 632 else 633 db_printf("Step to enter the remote GDB backend.\n"); 634 } 635 636 static void 637 db_stack_trace(db_expr_t tid, boolean_t hastid, db_expr_t count, char *modif) 638 { 639 struct thread *td; 640 db_expr_t radix; 641 pid_t pid; 642 int t; 643 644 /* 645 * We parse our own arguments. We don't like the default radix. 646 */ 647 radix = db_radix; 648 db_radix = 10; 649 hastid = db_expression(&tid); 650 t = db_read_token(); 651 if (t == tCOMMA) { 652 if (!db_expression(&count)) { 653 db_printf("Count missing\n"); 654 db_flush_lex(); 655 return; 656 } 657 } else { 658 db_unread_token(t); 659 count = -1; 660 } 661 db_skip_to_eol(); 662 db_radix = radix; 663 664 if (hastid) { 665 td = kdb_thr_lookup((lwpid_t)tid); 666 if (td == NULL) 667 td = kdb_thr_from_pid((pid_t)tid); 668 if (td == NULL) { 669 db_printf("Thread %d not found\n", (int)tid); 670 return; 671 } 672 } else 673 td = kdb_thread; 674 if (td->td_proc != NULL) 675 pid = td->td_proc->p_pid; 676 else 677 pid = -1; 678 db_printf("Tracing pid %d tid %ld td %p\n", pid, (long)td->td_tid, td); 679 db_trace_thread(td, count); 680 } 681 682 static void 683 db_stack_trace_all(db_expr_t dummy, boolean_t dummy2, db_expr_t dummy3, 684 char *dummy4) 685 { 686 struct proc *p; 687 struct thread *td; 688 int quit; 689 690 quit = 0; 691 db_setup_paging(db_simple_pager, &quit, db_lines_per_page); 692 for (p = LIST_FIRST(&allproc); p != NULL; p = LIST_NEXT(p, p_list)) { 693 FOREACH_THREAD_IN_PROC(p, td) { 694 db_printf("\nTracing command %s pid %d tid %ld td %p\n", 695 p->p_comm, p->p_pid, (long)td->td_tid, td); 696 db_trace_thread(td, -1); 697 if (quit) 698 return; 699 } 700 } 701 } 702