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 /* XXX this is actually forward-static. */ 77 extern struct command db_show_cmds[]; 78 79 /* 80 * if 'ed' style: 'dot' is set at start of last item printed, 81 * and '+' points to next line. 82 * Otherwise: 'dot' points to next item, '..' points to last. 83 */ 84 static boolean_t db_ed_style = TRUE; 85 86 /* 87 * Utility routine - discard tokens through end-of-line. 88 */ 89 void 90 db_skip_to_eol() 91 { 92 int t; 93 do { 94 t = db_read_token(); 95 } while (t != tEOL); 96 } 97 98 /* 99 * Results of command search. 100 */ 101 #define CMD_UNIQUE 0 102 #define CMD_FOUND 1 103 #define CMD_NONE 2 104 #define CMD_AMBIGUOUS 3 105 #define CMD_HELP 4 106 107 static void db_cmd_list(struct command *table, struct command **aux_tablep, 108 struct command **aux_tablep_end); 109 static int db_cmd_search(char *name, struct command *table, 110 struct command **aux_tablep, 111 struct command **aux_tablep_end, struct command **cmdp); 112 static void db_command(struct command **last_cmdp, 113 struct command *cmd_table, struct command **aux_cmd_tablep, 114 struct command **aux_cmd_tablep_end); 115 116 /* 117 * Search for command prefix. 118 */ 119 static int 120 db_cmd_search(name, table, aux_tablep, aux_tablep_end, cmdp) 121 char * name; 122 struct command *table; 123 struct command **aux_tablep; 124 struct command **aux_tablep_end; 125 struct command **cmdp; /* out */ 126 { 127 struct command *cmd; 128 struct command **aux_cmdp; 129 int result = CMD_NONE; 130 131 for (cmd = table; cmd->name != 0; cmd++) { 132 register char *lp; 133 register char *rp; 134 register int c; 135 136 lp = name; 137 rp = cmd->name; 138 while ((c = *lp) == *rp) { 139 if (c == 0) { 140 /* complete match */ 141 *cmdp = cmd; 142 return (CMD_UNIQUE); 143 } 144 lp++; 145 rp++; 146 } 147 if (c == 0) { 148 /* end of name, not end of command - 149 partial match */ 150 if (result == CMD_FOUND) { 151 result = CMD_AMBIGUOUS; 152 /* but keep looking for a full match - 153 this lets us match single letters */ 154 } 155 else { 156 *cmdp = cmd; 157 result = CMD_FOUND; 158 } 159 } 160 } 161 if (result == CMD_NONE && aux_tablep != 0) 162 /* XXX repeat too much code. */ 163 for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) { 164 register char *lp; 165 register char *rp; 166 register int c; 167 168 lp = name; 169 rp = (*aux_cmdp)->name; 170 while ((c = *lp) == *rp) { 171 if (c == 0) { 172 /* complete match */ 173 *cmdp = *aux_cmdp; 174 return (CMD_UNIQUE); 175 } 176 lp++; 177 rp++; 178 } 179 if (c == 0) { 180 /* end of name, not end of command - 181 partial match */ 182 if (result == CMD_FOUND) { 183 result = CMD_AMBIGUOUS; 184 /* but keep looking for a full match - 185 this lets us match single letters */ 186 } 187 else { 188 *cmdp = *aux_cmdp; 189 result = CMD_FOUND; 190 } 191 } 192 } 193 if (result == CMD_NONE) { 194 /* check for 'help' */ 195 if (name[0] == 'h' && name[1] == 'e' 196 && name[2] == 'l' && name[3] == 'p') 197 result = CMD_HELP; 198 } 199 return (result); 200 } 201 202 static void 203 db_cmd_list(table, aux_tablep, aux_tablep_end) 204 struct command *table; 205 struct command **aux_tablep; 206 struct command **aux_tablep_end; 207 { 208 register struct command *cmd; 209 register struct command **aux_cmdp; 210 211 for (cmd = table; cmd->name != 0; cmd++) { 212 db_printf("%-12s", cmd->name); 213 db_end_line(); 214 } 215 if (aux_tablep == 0) 216 return; 217 for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) { 218 db_printf("%-12s", (*aux_cmdp)->name); 219 db_end_line(); 220 } 221 } 222 223 static void 224 db_command(last_cmdp, cmd_table, aux_cmd_tablep, aux_cmd_tablep_end) 225 struct command **last_cmdp; /* IN_OUT */ 226 struct command *cmd_table; 227 struct command **aux_cmd_tablep; 228 struct command **aux_cmd_tablep_end; 229 { 230 struct command *cmd; 231 int t; 232 char modif[TOK_STRING_SIZE]; 233 db_expr_t addr, count; 234 boolean_t have_addr = FALSE; 235 int result; 236 237 t = db_read_token(); 238 if (t == tEOL) { 239 /* empty line repeats last command, at 'next' */ 240 cmd = *last_cmdp; 241 addr = (db_expr_t)db_next; 242 have_addr = FALSE; 243 count = 1; 244 modif[0] = '\0'; 245 } 246 else if (t == tEXCL) { 247 db_fncall((db_expr_t)0, (boolean_t)0, (db_expr_t)0, (char *)0); 248 return; 249 } 250 else if (t != tIDENT) { 251 db_printf("?\n"); 252 db_flush_lex(); 253 return; 254 } 255 else { 256 /* 257 * Search for command 258 */ 259 while (cmd_table) { 260 result = db_cmd_search(db_tok_string, 261 cmd_table, 262 aux_cmd_tablep, 263 aux_cmd_tablep_end, 264 &cmd); 265 switch (result) { 266 case CMD_NONE: 267 db_printf("No such command\n"); 268 db_flush_lex(); 269 return; 270 case CMD_AMBIGUOUS: 271 db_printf("Ambiguous\n"); 272 db_flush_lex(); 273 return; 274 case CMD_HELP: 275 db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end); 276 db_flush_lex(); 277 return; 278 default: 279 break; 280 } 281 if ((cmd_table = cmd->more) != 0) { 282 /* XXX usually no more aux's. */ 283 aux_cmd_tablep = 0; 284 if (cmd_table == db_show_cmds) { 285 aux_cmd_tablep = SET_BEGIN(db_show_cmd_set); 286 aux_cmd_tablep_end = SET_LIMIT(db_show_cmd_set); 287 } 288 289 t = db_read_token(); 290 if (t != tIDENT) { 291 db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end); 292 db_flush_lex(); 293 return; 294 } 295 } 296 } 297 298 if ((cmd->flag & CS_OWN) == 0) { 299 /* 300 * Standard syntax: 301 * command [/modifier] [addr] [,count] 302 */ 303 t = db_read_token(); 304 if (t == tSLASH) { 305 t = db_read_token(); 306 if (t != tIDENT) { 307 db_printf("Bad modifier\n"); 308 db_flush_lex(); 309 return; 310 } 311 db_strcpy(modif, db_tok_string); 312 } 313 else { 314 db_unread_token(t); 315 modif[0] = '\0'; 316 } 317 318 if (db_expression(&addr)) { 319 db_dot = (db_addr_t) addr; 320 db_last_addr = db_dot; 321 have_addr = TRUE; 322 } 323 else { 324 addr = (db_expr_t) db_dot; 325 have_addr = FALSE; 326 } 327 t = db_read_token(); 328 if (t == tCOMMA) { 329 if (!db_expression(&count)) { 330 db_printf("Count missing\n"); 331 db_flush_lex(); 332 return; 333 } 334 } 335 else { 336 db_unread_token(t); 337 count = -1; 338 } 339 if ((cmd->flag & CS_MORE) == 0) { 340 db_skip_to_eol(); 341 } 342 } 343 } 344 *last_cmdp = cmd; 345 if (cmd != 0) { 346 /* 347 * Execute the command. 348 */ 349 (*cmd->fcn)(addr, have_addr, count, modif); 350 db_setup_paging(NULL, NULL, -1); 351 352 if (cmd->flag & CS_SET_DOT) { 353 /* 354 * If command changes dot, set dot to 355 * previous address displayed (if 'ed' style). 356 */ 357 if (db_ed_style) { 358 db_dot = db_prev; 359 } 360 else { 361 db_dot = db_next; 362 } 363 } 364 else { 365 /* 366 * If command does not change dot, 367 * set 'next' location to be the same. 368 */ 369 db_next = db_dot; 370 } 371 } 372 } 373 374 /* 375 * 'show' commands 376 */ 377 378 static struct command db_show_all_cmds[] = { 379 { "procs", db_ps, 0, 0 }, 380 { (char *)0 } 381 }; 382 383 static struct command db_show_cmds[] = { 384 { "all", 0, 0, db_show_all_cmds }, 385 { "registers", db_show_regs, 0, 0 }, 386 { "breaks", db_listbreak_cmd, 0, 0 }, 387 { "threads", db_show_threads, 0, 0 }, 388 { (char *)0, } 389 }; 390 391 static struct command db_command_table[] = { 392 { "print", db_print_cmd, 0, 0 }, 393 { "p", db_print_cmd, 0, 0 }, 394 { "examine", db_examine_cmd, CS_SET_DOT, 0 }, 395 { "x", db_examine_cmd, CS_SET_DOT, 0 }, 396 { "search", db_search_cmd, CS_OWN|CS_SET_DOT, 0 }, 397 { "set", db_set_cmd, CS_OWN, 0 }, 398 { "write", db_write_cmd, CS_MORE|CS_SET_DOT, 0 }, 399 { "w", db_write_cmd, CS_MORE|CS_SET_DOT, 0 }, 400 { "delete", db_delete_cmd, 0, 0 }, 401 { "d", db_delete_cmd, 0, 0 }, 402 { "break", db_breakpoint_cmd, 0, 0 }, 403 { "dwatch", db_deletewatch_cmd, 0, 0 }, 404 { "watch", db_watchpoint_cmd, CS_MORE,0 }, 405 { "dhwatch", db_deletehwatch_cmd, 0, 0 }, 406 { "hwatch", db_hwatchpoint_cmd, 0, 0 }, 407 { "step", db_single_step_cmd, 0, 0 }, 408 { "s", db_single_step_cmd, 0, 0 }, 409 { "continue", db_continue_cmd, 0, 0 }, 410 { "c", db_continue_cmd, 0, 0 }, 411 { "until", db_trace_until_call_cmd,0, 0 }, 412 { "next", db_trace_until_matching_cmd,0, 0 }, 413 { "match", db_trace_until_matching_cmd,0, 0 }, 414 { "trace", db_stack_trace, CS_OWN, 0 }, 415 { "where", db_stack_trace, CS_OWN, 0 }, 416 { "call", db_fncall, CS_OWN, 0 }, 417 { "show", 0, 0, db_show_cmds }, 418 { "ps", db_ps, 0, 0 }, 419 { "gdb", db_gdb, 0, 0 }, 420 { "reset", db_reset, 0, 0 }, 421 { "kill", db_kill, CS_OWN, 0 }, 422 { "watchdog", db_watchdog, 0, 0 }, 423 { "thread", db_set_thread, CS_OWN, 0 }, 424 { (char *)0, } 425 }; 426 427 static struct command *db_last_command = 0; 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 static void 476 db_fncall(dummy1, dummy2, dummy3, dummy4) 477 db_expr_t dummy1; 478 boolean_t dummy2; 479 db_expr_t dummy3; 480 char * dummy4; 481 { 482 db_expr_t fn_addr; 483 #define MAXARGS 11 /* XXX only 10 are passed */ 484 db_expr_t args[MAXARGS]; 485 int nargs = 0; 486 db_expr_t retval; 487 typedef db_expr_t fcn_10args_t(db_expr_t, db_expr_t, db_expr_t, 488 db_expr_t, db_expr_t, db_expr_t, db_expr_t, 489 db_expr_t, db_expr_t, db_expr_t); 490 fcn_10args_t *func; 491 int t; 492 493 if (!db_expression(&fn_addr)) { 494 db_printf("Bad function\n"); 495 db_flush_lex(); 496 return; 497 } 498 func = (fcn_10args_t *)fn_addr; /* XXX */ 499 500 t = db_read_token(); 501 if (t == tLPAREN) { 502 if (db_expression(&args[0])) { 503 nargs++; 504 while ((t = db_read_token()) == tCOMMA) { 505 if (nargs == MAXARGS) { 506 db_printf("Too many arguments\n"); 507 db_flush_lex(); 508 return; 509 } 510 if (!db_expression(&args[nargs])) { 511 db_printf("Argument missing\n"); 512 db_flush_lex(); 513 return; 514 } 515 nargs++; 516 } 517 db_unread_token(t); 518 } 519 if (db_read_token() != tRPAREN) { 520 db_printf("?\n"); 521 db_flush_lex(); 522 return; 523 } 524 } 525 db_skip_to_eol(); 526 527 while (nargs < MAXARGS) { 528 args[nargs++] = 0; 529 } 530 531 retval = (*func)(args[0], args[1], args[2], args[3], args[4], 532 args[5], args[6], args[7], args[8], args[9] ); 533 db_printf("%#lr\n", (long)retval); 534 } 535 536 static void 537 db_kill(dummy1, dummy2, dummy3, dummy4) 538 db_expr_t dummy1; 539 boolean_t dummy2; 540 db_expr_t dummy3; 541 char * dummy4; 542 { 543 db_expr_t old_radix, pid, sig; 544 struct proc *p; 545 546 #define DB_ERROR(f) do { db_printf f; db_flush_lex(); goto out; } while (0) 547 548 /* 549 * PIDs and signal numbers are typically represented in base 550 * 10, so make that the default here. It can, of course, be 551 * overridden by specifying a prefix. 552 */ 553 old_radix = db_radix; 554 db_radix = 10; 555 /* Retrieve arguments. */ 556 if (!db_expression(&sig)) 557 DB_ERROR(("Missing signal number\n")); 558 if (!db_expression(&pid)) 559 DB_ERROR(("Missing process ID\n")); 560 db_skip_to_eol(); 561 if (sig < 0 || sig > _SIG_MAXSIG) 562 DB_ERROR(("Signal number out of range\n")); 563 564 /* 565 * Find the process in question. allproc_lock is not needed 566 * since we're in DDB. 567 */ 568 /* sx_slock(&allproc_lock); */ 569 LIST_FOREACH(p, &allproc, p_list) 570 if (p->p_pid == pid) 571 break; 572 /* sx_sunlock(&allproc_lock); */ 573 if (p == NULL) 574 DB_ERROR(("Can't find process with pid %ld\n", (long) pid)); 575 576 /* If it's already locked, bail; otherwise, do the deed. */ 577 if (PROC_TRYLOCK(p) == 0) 578 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid)); 579 else { 580 psignal(p, sig); 581 PROC_UNLOCK(p); 582 } 583 584 out: 585 db_radix = old_radix; 586 #undef DB_ERROR 587 } 588 589 static void 590 db_reset(dummy1, dummy2, dummy3, dummy4) 591 db_expr_t dummy1; 592 boolean_t dummy2; 593 db_expr_t dummy3; 594 char * dummy4; 595 { 596 597 cpu_reset(); 598 } 599 600 static void 601 db_watchdog(dummy1, dummy2, dummy3, dummy4) 602 db_expr_t dummy1; 603 boolean_t dummy2; 604 db_expr_t dummy3; 605 char * dummy4; 606 { 607 int i; 608 609 /* 610 * XXX: It might make sense to be able to set the watchdog to a 611 * XXX: timeout here so that failure or hang as a result of subsequent 612 * XXX: ddb commands could be recovered by a reset. 613 */ 614 615 EVENTHANDLER_INVOKE(watchdog_list, 0, &i); 616 } 617 618 static void 619 db_gdb(db_expr_t dummy1, boolean_t dummy2, db_expr_t dummy3, char *dummy4) 620 { 621 622 if (kdb_dbbe_select("gdb") != 0) 623 db_printf("The remote GDB backend could not be selected.\n"); 624 else 625 db_printf("Step to enter the remote GDB backend.\n"); 626 } 627 628 static void 629 db_stack_trace(db_expr_t tid, boolean_t hastid, db_expr_t count, char *modif) 630 { 631 struct thread *td; 632 db_expr_t radix; 633 int t; 634 635 /* 636 * We parse our own arguments. We don't like the default radix. 637 */ 638 radix = db_radix; 639 db_radix = 10; 640 hastid = db_expression(&tid); 641 t = db_read_token(); 642 if (t == tCOMMA) { 643 if (!db_expression(&count)) { 644 db_printf("Count missing\n"); 645 db_flush_lex(); 646 return; 647 } 648 } else { 649 db_unread_token(t); 650 count = -1; 651 } 652 db_skip_to_eol(); 653 db_radix = radix; 654 655 if (hastid) { 656 td = kdb_thr_lookup((lwpid_t)tid); 657 if (td == NULL) 658 td = kdb_thr_from_pid((pid_t)tid); 659 if (td == NULL) { 660 db_printf("Thread %d not found\n", (int)tid); 661 return; 662 } 663 } else 664 td = kdb_thread; 665 db_trace_thread(td, count); 666 } 667