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 SET_DECLARE(db_show_all_cmd_set, struct command); 69 70 static db_cmdfcn_t db_fncall; 71 static db_cmdfcn_t db_gdb; 72 static db_cmdfcn_t db_halt; 73 static db_cmdfcn_t db_kill; 74 static db_cmdfcn_t db_reset; 75 static db_cmdfcn_t db_stack_trace; 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_all_cmds[] = { 84 { (char *)0 } 85 }; 86 87 static struct command_table db_show_all_table = { 88 db_show_all_cmds, 89 SET_BEGIN(db_show_all_cmd_set), 90 SET_LIMIT(db_show_all_cmd_set) 91 }; 92 93 static struct command db_show_cmds[] = { 94 { "all", 0, 0, &db_show_all_table }, 95 { "registers", db_show_regs, 0, 0 }, 96 { "breaks", db_listbreak_cmd, 0, 0 }, 97 { "threads", db_show_threads, 0, 0 }, 98 { (char *)0, } 99 }; 100 101 static struct command_table db_show_table = { 102 db_show_cmds, 103 SET_BEGIN(db_show_cmd_set), 104 SET_LIMIT(db_show_cmd_set) 105 }; 106 107 static struct command db_commands[] = { 108 { "print", db_print_cmd, 0, 0 }, 109 { "p", db_print_cmd, 0, 0 }, 110 { "examine", db_examine_cmd, CS_SET_DOT, 0 }, 111 { "x", db_examine_cmd, CS_SET_DOT, 0 }, 112 { "search", db_search_cmd, CS_OWN|CS_SET_DOT, 0 }, 113 { "set", db_set_cmd, CS_OWN, 0 }, 114 { "write", db_write_cmd, CS_MORE|CS_SET_DOT, 0 }, 115 { "w", db_write_cmd, CS_MORE|CS_SET_DOT, 0 }, 116 { "delete", db_delete_cmd, 0, 0 }, 117 { "d", db_delete_cmd, 0, 0 }, 118 { "break", db_breakpoint_cmd, 0, 0 }, 119 { "b", db_breakpoint_cmd, 0, 0 }, 120 { "dwatch", db_deletewatch_cmd, 0, 0 }, 121 { "watch", db_watchpoint_cmd, CS_MORE,0 }, 122 { "dhwatch", db_deletehwatch_cmd, 0, 0 }, 123 { "hwatch", db_hwatchpoint_cmd, 0, 0 }, 124 { "step", db_single_step_cmd, 0, 0 }, 125 { "s", db_single_step_cmd, 0, 0 }, 126 { "continue", db_continue_cmd, 0, 0 }, 127 { "c", db_continue_cmd, 0, 0 }, 128 { "until", db_trace_until_call_cmd,0, 0 }, 129 { "next", db_trace_until_matching_cmd,0, 0 }, 130 { "match", db_trace_until_matching_cmd,0, 0 }, 131 { "trace", db_stack_trace, CS_OWN, 0 }, 132 { "t", db_stack_trace, CS_OWN, 0 }, 133 { "alltrace", db_stack_trace_all, 0, 0 }, 134 { "where", db_stack_trace, CS_OWN, 0 }, 135 { "bt", db_stack_trace, CS_OWN, 0 }, 136 { "call", db_fncall, CS_OWN, 0 }, 137 { "show", 0, 0, &db_show_table }, 138 { "ps", db_ps, 0, 0 }, 139 { "gdb", db_gdb, 0, 0 }, 140 { "halt", db_halt, 0, 0 }, 141 { "reboot", db_reset, 0, 0 }, 142 { "reset", db_reset, 0, 0 }, 143 { "kill", db_kill, CS_OWN, 0 }, 144 { "watchdog", db_watchdog, 0, 0 }, 145 { "thread", db_set_thread, CS_OWN, 0 }, 146 { "run", db_run_cmd, CS_OWN, 0 }, 147 { "script", db_script_cmd, CS_OWN, 0 }, 148 { "scripts", db_scripts_cmd, 0, 0 }, 149 { "unscript", db_unscript_cmd, CS_OWN, 0 }, 150 { "capture", db_capture_cmd, CS_OWN, 0 }, 151 { "textdump", db_textdump_cmd, CS_OWN, 0 }, 152 { (char *)0, } 153 }; 154 155 static struct command_table db_command_table = { 156 db_commands, 157 SET_BEGIN(db_cmd_set), 158 SET_LIMIT(db_cmd_set) 159 }; 160 161 static struct command *db_last_command = 0; 162 163 /* 164 * if 'ed' style: 'dot' is set at start of last item printed, 165 * and '+' points to next line. 166 * Otherwise: 'dot' points to next item, '..' points to last. 167 */ 168 static boolean_t db_ed_style = TRUE; 169 170 /* 171 * Utility routine - discard tokens through end-of-line. 172 */ 173 void 174 db_skip_to_eol() 175 { 176 int t; 177 do { 178 t = db_read_token(); 179 } while (t != tEOL); 180 } 181 182 /* 183 * Results of command search. 184 */ 185 #define CMD_UNIQUE 0 186 #define CMD_FOUND 1 187 #define CMD_NONE 2 188 #define CMD_AMBIGUOUS 3 189 #define CMD_HELP 4 190 191 static void db_cmd_match(char *name, struct command *cmd, 192 struct command **cmdp, int *resultp); 193 static void db_cmd_list(struct command_table *table); 194 static int db_cmd_search(char *name, struct command_table *table, 195 struct command **cmdp); 196 static void db_command(struct command **last_cmdp, 197 struct command_table *cmd_table, int dopager); 198 199 /* 200 * Helper function to match a single command. 201 */ 202 static void 203 db_cmd_match(name, cmd, cmdp, resultp) 204 char * name; 205 struct command *cmd; 206 struct command **cmdp; /* out */ 207 int * resultp; 208 { 209 char *lp, *rp; 210 int c; 211 212 lp = name; 213 rp = cmd->name; 214 while ((c = *lp) == *rp) { 215 if (c == 0) { 216 /* complete match */ 217 *cmdp = cmd; 218 *resultp = CMD_UNIQUE; 219 return; 220 } 221 lp++; 222 rp++; 223 } 224 if (c == 0) { 225 /* end of name, not end of command - 226 partial match */ 227 if (*resultp == CMD_FOUND) { 228 *resultp = CMD_AMBIGUOUS; 229 /* but keep looking for a full match - 230 this lets us match single letters */ 231 } else { 232 *cmdp = cmd; 233 *resultp = CMD_FOUND; 234 } 235 } 236 } 237 238 /* 239 * Search for command prefix. 240 */ 241 static int 242 db_cmd_search(name, table, cmdp) 243 char * name; 244 struct command_table *table; 245 struct command **cmdp; /* out */ 246 { 247 struct command *cmd; 248 struct command **aux_cmdp; 249 int result = CMD_NONE; 250 251 for (cmd = table->table; cmd->name != 0; cmd++) { 252 db_cmd_match(name, cmd, cmdp, &result); 253 if (result == CMD_UNIQUE) 254 return (CMD_UNIQUE); 255 } 256 if (table->aux_tablep != NULL) 257 for (aux_cmdp = table->aux_tablep; 258 aux_cmdp < table->aux_tablep_end; 259 aux_cmdp++) { 260 db_cmd_match(name, *aux_cmdp, cmdp, &result); 261 if (result == CMD_UNIQUE) 262 return (CMD_UNIQUE); 263 } 264 if (result == CMD_NONE) { 265 /* check for 'help' */ 266 if (name[0] == 'h' && name[1] == 'e' 267 && name[2] == 'l' && name[3] == 'p') 268 result = CMD_HELP; 269 } 270 return (result); 271 } 272 273 static void 274 db_cmd_list(table) 275 struct command_table *table; 276 { 277 register struct command *cmd; 278 register struct command **aux_cmdp; 279 280 for (cmd = table->table; cmd->name != 0; cmd++) { 281 db_printf("%-12s", cmd->name); 282 db_end_line(12); 283 } 284 if (table->aux_tablep == NULL) 285 return; 286 for (aux_cmdp = table->aux_tablep; aux_cmdp < table->aux_tablep_end; 287 aux_cmdp++) { 288 db_printf("%-12s", (*aux_cmdp)->name); 289 db_end_line(12); 290 } 291 } 292 293 static void 294 db_command(last_cmdp, cmd_table, dopager) 295 struct command **last_cmdp; /* IN_OUT */ 296 struct command_table *cmd_table; 297 int dopager; 298 { 299 struct command *cmd; 300 int t; 301 char modif[TOK_STRING_SIZE]; 302 db_expr_t addr, count; 303 boolean_t have_addr = FALSE; 304 int result; 305 306 t = db_read_token(); 307 if (t == tEOL) { 308 /* empty line repeats last command, at 'next' */ 309 cmd = *last_cmdp; 310 addr = (db_expr_t)db_next; 311 have_addr = FALSE; 312 count = 1; 313 modif[0] = '\0'; 314 } 315 else if (t == tEXCL) { 316 db_fncall((db_expr_t)0, (boolean_t)0, (db_expr_t)0, (char *)0); 317 return; 318 } 319 else if (t != tIDENT) { 320 db_printf("?\n"); 321 db_flush_lex(); 322 return; 323 } 324 else { 325 /* 326 * Search for command 327 */ 328 while (cmd_table) { 329 result = db_cmd_search(db_tok_string, 330 cmd_table, 331 &cmd); 332 switch (result) { 333 case CMD_NONE: 334 db_printf("No such command\n"); 335 db_flush_lex(); 336 return; 337 case CMD_AMBIGUOUS: 338 db_printf("Ambiguous\n"); 339 db_flush_lex(); 340 return; 341 case CMD_HELP: 342 db_cmd_list(cmd_table); 343 db_flush_lex(); 344 return; 345 default: 346 break; 347 } 348 if ((cmd_table = cmd->more) != NULL) { 349 t = db_read_token(); 350 if (t != tIDENT) { 351 db_cmd_list(cmd_table); 352 db_flush_lex(); 353 return; 354 } 355 } 356 } 357 358 if ((cmd->flag & CS_OWN) == 0) { 359 /* 360 * Standard syntax: 361 * command [/modifier] [addr] [,count] 362 */ 363 t = db_read_token(); 364 if (t == tSLASH) { 365 t = db_read_token(); 366 if (t != tIDENT) { 367 db_printf("Bad modifier\n"); 368 db_flush_lex(); 369 return; 370 } 371 db_strcpy(modif, db_tok_string); 372 } 373 else { 374 db_unread_token(t); 375 modif[0] = '\0'; 376 } 377 378 if (db_expression(&addr)) { 379 db_dot = (db_addr_t) addr; 380 db_last_addr = db_dot; 381 have_addr = TRUE; 382 } 383 else { 384 addr = (db_expr_t) db_dot; 385 have_addr = FALSE; 386 } 387 t = db_read_token(); 388 if (t == tCOMMA) { 389 if (!db_expression(&count)) { 390 db_printf("Count missing\n"); 391 db_flush_lex(); 392 return; 393 } 394 } 395 else { 396 db_unread_token(t); 397 count = -1; 398 } 399 if ((cmd->flag & CS_MORE) == 0) { 400 db_skip_to_eol(); 401 } 402 } 403 } 404 *last_cmdp = cmd; 405 if (cmd != 0) { 406 /* 407 * Execute the command. 408 */ 409 if (dopager) 410 db_enable_pager(); 411 else 412 db_disable_pager(); 413 (*cmd->fcn)(addr, have_addr, count, modif); 414 if (dopager) 415 db_disable_pager(); 416 417 if (cmd->flag & CS_SET_DOT) { 418 /* 419 * If command changes dot, set dot to 420 * previous address displayed (if 'ed' style). 421 */ 422 if (db_ed_style) { 423 db_dot = db_prev; 424 } 425 else { 426 db_dot = db_next; 427 } 428 } 429 else { 430 /* 431 * If command does not change dot, 432 * set 'next' location to be the same. 433 */ 434 db_next = db_dot; 435 } 436 } 437 } 438 439 /* 440 * At least one non-optional command must be implemented using 441 * DB_COMMAND() so that db_cmd_set gets created. Here is one. 442 */ 443 DB_COMMAND(panic, db_panic) 444 { 445 db_disable_pager(); 446 panic("from debugger"); 447 } 448 449 void 450 db_command_loop() 451 { 452 /* 453 * Initialize 'prev' and 'next' to dot. 454 */ 455 db_prev = db_dot; 456 db_next = db_dot; 457 458 db_cmd_loop_done = 0; 459 while (!db_cmd_loop_done) { 460 if (db_print_position() != 0) 461 db_printf("\n"); 462 463 db_printf("db> "); 464 (void) db_read_line(); 465 466 db_command(&db_last_command, &db_command_table, /* dopager */ 1); 467 } 468 } 469 470 /* 471 * Execute a command on behalf of a script. The caller is responsible for 472 * making sure that the command string is < DB_MAXLINE or it will be 473 * truncated. 474 * 475 * XXXRW: Runs by injecting faked input into DDB input stream; it would be 476 * nicer to use an alternative approach that didn't mess with the previous 477 * command buffer. 478 */ 479 void 480 db_command_script(const char *command) 481 { 482 db_prev = db_next = db_dot; 483 db_inject_line(command); 484 db_command(&db_last_command, &db_command_table, /* dopager */ 0); 485 } 486 487 void 488 db_error(s) 489 const char *s; 490 { 491 if (s) 492 db_printf("%s", s); 493 db_flush_lex(); 494 kdb_reenter(); 495 } 496 497 498 /* 499 * Call random function: 500 * !expr(arg,arg,arg) 501 */ 502 503 /* The generic implementation supports a maximum of 10 arguments. */ 504 typedef db_expr_t __db_f(db_expr_t, db_expr_t, db_expr_t, db_expr_t, 505 db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t); 506 507 static __inline int 508 db_fncall_generic(db_expr_t addr, db_expr_t *rv, int nargs, db_expr_t args[]) 509 { 510 __db_f *f = (__db_f *)addr; 511 512 if (nargs > 10) { 513 db_printf("Too many arguments (max 10)\n"); 514 return (0); 515 } 516 *rv = (*f)(args[0], args[1], args[2], args[3], args[4], args[5], 517 args[6], args[7], args[8], args[9]); 518 return (1); 519 } 520 521 static void 522 db_fncall(dummy1, dummy2, dummy3, dummy4) 523 db_expr_t dummy1; 524 boolean_t dummy2; 525 db_expr_t dummy3; 526 char * dummy4; 527 { 528 db_expr_t fn_addr; 529 db_expr_t args[DB_MAXARGS]; 530 int nargs = 0; 531 db_expr_t retval; 532 int t; 533 534 if (!db_expression(&fn_addr)) { 535 db_printf("Bad function\n"); 536 db_flush_lex(); 537 return; 538 } 539 540 t = db_read_token(); 541 if (t == tLPAREN) { 542 if (db_expression(&args[0])) { 543 nargs++; 544 while ((t = db_read_token()) == tCOMMA) { 545 if (nargs == DB_MAXARGS) { 546 db_printf("Too many arguments (max %d)\n", DB_MAXARGS); 547 db_flush_lex(); 548 return; 549 } 550 if (!db_expression(&args[nargs])) { 551 db_printf("Argument missing\n"); 552 db_flush_lex(); 553 return; 554 } 555 nargs++; 556 } 557 db_unread_token(t); 558 } 559 if (db_read_token() != tRPAREN) { 560 db_printf("?\n"); 561 db_flush_lex(); 562 return; 563 } 564 } 565 db_skip_to_eol(); 566 db_disable_pager(); 567 568 if (DB_CALL(fn_addr, &retval, nargs, args)) 569 db_printf("= %#lr\n", (long)retval); 570 } 571 572 static void 573 db_halt(db_expr_t dummy, boolean_t dummy2, db_expr_t dummy3, char *dummy4) 574 { 575 576 cpu_halt(); 577 } 578 579 static void 580 db_kill(dummy1, dummy2, dummy3, dummy4) 581 db_expr_t dummy1; 582 boolean_t dummy2; 583 db_expr_t dummy3; 584 char * dummy4; 585 { 586 db_expr_t old_radix, pid, sig; 587 struct proc *p; 588 589 #define DB_ERROR(f) do { db_printf f; db_flush_lex(); goto out; } while (0) 590 591 /* 592 * PIDs and signal numbers are typically represented in base 593 * 10, so make that the default here. It can, of course, be 594 * overridden by specifying a prefix. 595 */ 596 old_radix = db_radix; 597 db_radix = 10; 598 /* Retrieve arguments. */ 599 if (!db_expression(&sig)) 600 DB_ERROR(("Missing signal number\n")); 601 if (!db_expression(&pid)) 602 DB_ERROR(("Missing process ID\n")); 603 db_skip_to_eol(); 604 if (sig < 1 || sig > _SIG_MAXSIG) 605 DB_ERROR(("Signal number out of range\n")); 606 607 /* 608 * Find the process in question. allproc_lock is not needed 609 * since we're in DDB. 610 */ 611 /* sx_slock(&allproc_lock); */ 612 FOREACH_PROC_IN_SYSTEM(p) 613 if (p->p_pid == pid) 614 break; 615 /* sx_sunlock(&allproc_lock); */ 616 if (p == NULL) 617 DB_ERROR(("Can't find process with pid %ld\n", (long) pid)); 618 619 /* If it's already locked, bail; otherwise, do the deed. */ 620 if (PROC_TRYLOCK(p) == 0) 621 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid)); 622 else { 623 psignal(p, sig); 624 PROC_UNLOCK(p); 625 } 626 627 out: 628 db_radix = old_radix; 629 #undef DB_ERROR 630 } 631 632 static void 633 db_reset(dummy1, dummy2, dummy3, dummy4) 634 db_expr_t dummy1; 635 boolean_t dummy2; 636 db_expr_t dummy3; 637 char * dummy4; 638 { 639 640 cpu_reset(); 641 } 642 643 static void 644 db_watchdog(dummy1, dummy2, dummy3, dummy4) 645 db_expr_t dummy1; 646 boolean_t dummy2; 647 db_expr_t dummy3; 648 char * dummy4; 649 { 650 int i; 651 652 /* 653 * XXX: It might make sense to be able to set the watchdog to a 654 * XXX: timeout here so that failure or hang as a result of subsequent 655 * XXX: ddb commands could be recovered by a reset. 656 */ 657 658 EVENTHANDLER_INVOKE(watchdog_list, 0, &i); 659 } 660 661 static void 662 db_gdb(db_expr_t dummy1, boolean_t dummy2, db_expr_t dummy3, char *dummy4) 663 { 664 665 if (kdb_dbbe_select("gdb") != 0) 666 db_printf("The remote GDB backend could not be selected.\n"); 667 else 668 db_printf("Step to enter the remote GDB backend.\n"); 669 } 670 671 static void 672 db_stack_trace(db_expr_t tid, boolean_t hastid, db_expr_t count, char *modif) 673 { 674 struct thread *td; 675 db_expr_t radix; 676 pid_t pid; 677 int t; 678 679 /* 680 * We parse our own arguments. We don't like the default radix. 681 */ 682 radix = db_radix; 683 db_radix = 10; 684 hastid = db_expression(&tid); 685 t = db_read_token(); 686 if (t == tCOMMA) { 687 if (!db_expression(&count)) { 688 db_printf("Count missing\n"); 689 db_flush_lex(); 690 return; 691 } 692 } else { 693 db_unread_token(t); 694 count = -1; 695 } 696 db_skip_to_eol(); 697 db_radix = radix; 698 699 if (hastid) { 700 td = kdb_thr_lookup((lwpid_t)tid); 701 if (td == NULL) 702 td = kdb_thr_from_pid((pid_t)tid); 703 if (td == NULL) { 704 db_printf("Thread %d not found\n", (int)tid); 705 return; 706 } 707 } else 708 td = kdb_thread; 709 if (td->td_proc != NULL) 710 pid = td->td_proc->p_pid; 711 else 712 pid = -1; 713 db_printf("Tracing pid %d tid %ld td %p\n", pid, (long)td->td_tid, td); 714 db_trace_thread(td, count); 715 } 716 717 static void 718 db_stack_trace_all(db_expr_t dummy, boolean_t dummy2, db_expr_t dummy3, 719 char *dummy4) 720 { 721 struct proc *p; 722 struct thread *td; 723 jmp_buf jb; 724 void *prev_jb; 725 726 FOREACH_PROC_IN_SYSTEM(p) { 727 prev_jb = kdb_jmpbuf(jb); 728 if (setjmp(jb) == 0) { 729 FOREACH_THREAD_IN_PROC(p, td) { 730 db_printf("\nTracing command %s pid %d tid %ld td %p\n", 731 p->p_comm, p->p_pid, (long)td->td_tid, td); 732 db_trace_thread(td, -1); 733 if (db_pager_quit) { 734 kdb_jmpbuf(prev_jb); 735 return; 736 } 737 } 738 } 739 kdb_jmpbuf(prev_jb); 740 } 741 } 742