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