xref: /netbsd-src/sys/ddb/db_command.c (revision 8ac07aec990b9d2e483062509d0a9fa5b4f57cf2)
1 /*	$NetBSD: db_command.c,v 1.114 2008/02/21 02:07:45 uwe Exp $	*/
2 /*
3  * Mach Operating System
4  * Copyright (c) 1991,1990 Carnegie Mellon University
5  * All Rights Reserved.
6  *
7  * Permission to use, copy, modify and distribute this software and its
8  * documentation is hereby granted, provided that both the copyright
9  * notice and this permission notice appear in all copies of the
10  * software, derivative works or modified versions, and any portions
11  * thereof, and that both notices appear in supporting documentation.
12  *
13  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
14  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
15  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
16  *
17  * Carnegie Mellon requests users of this software to return to
18  *
19  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
20  *  School of Computer Science
21  *  Carnegie Mellon University
22  *  Pittsburgh PA 15213-3890
23  *
24  * any improvements or extensions that they make and grant Carnegie the
25  * rights to redistribute these changes.
26  */
27 /*
28  * Copyright (c) 1996, 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc.
29  * All rights reserved.
30  *
31  * This code is derived from software contributed to The NetBSD Foundation
32  * by Adam Hamsik.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  * 1. Redistributions of source code must retain the above copyright
38  *    notice, this list of conditions and the following disclaimer.
39  * 2. Redistributions in binary form must reproduce the above copyright
40  *    notice, this list of conditions and the following disclaimer in the
41  *    documentation and/or other materials provided with the distribution.
42  * 3. All advertising materials mentioning features or use of this software
43  *    must display the following acknowledgement:
44  *        This product includes software developed by the NetBSD
45  *        Foundation, Inc. and its contributors.
46  * 4. Neither the name of The NetBSD Foundation nor the names of its
47  *    contributors may be used to endorse or promote products derived
48  *    from this software without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
51  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
52  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
53  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
54  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
55  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
56  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
57  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
58  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
59  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
60  * POSSIBILITY OF SUCH DAMAGE.
61  */
62 
63 /*
64  * Command dispatcher.
65  */
66 
67 #include <sys/cdefs.h>
68 __KERNEL_RCSID(0, "$NetBSD: db_command.c,v 1.114 2008/02/21 02:07:45 uwe Exp $");
69 
70 #include "opt_ddb.h"
71 #include "opt_kgdb.h"
72 #include "opt_inet.h"
73 #include "opt_ddbparam.h"
74 
75 #include <sys/param.h>
76 #include <sys/systm.h>
77 #include <sys/reboot.h>
78 #include <sys/device.h>
79 #include <sys/lwp.h>
80 #include <sys/malloc.h>
81 #include <sys/mbuf.h>
82 #include <sys/namei.h>
83 #include <sys/pool.h>
84 #include <sys/proc.h>
85 #include <sys/vnode.h>
86 #include <sys/vmem.h>
87 #include <sys/lockdebug.h>
88 #include <sys/sleepq.h>
89 #include <sys/cpu.h>
90 
91 /*include queue macros*/
92 #include <sys/queue.h>
93 
94 #include <machine/db_machdep.h>		/* type definitions */
95 
96 #if defined(_KERNEL_OPT)
97 #include "opt_multiprocessor.h"
98 #endif
99 
100 #include <ddb/db_lex.h>
101 #include <ddb/db_output.h>
102 #include <ddb/db_command.h>
103 #include <ddb/db_break.h>
104 #include <ddb/db_watch.h>
105 #include <ddb/db_run.h>
106 #include <ddb/db_variables.h>
107 #include <ddb/db_interface.h>
108 #include <ddb/db_sym.h>
109 #include <ddb/db_extern.h>
110 
111 #include <uvm/uvm_extern.h>
112 #include <uvm/uvm_ddb.h>
113 
114 #include "arp.h"
115 
116 /*
117  * Results of command search.
118  */
119 #define	CMD_UNIQUE	0
120 #define	CMD_FOUND	1
121 #define	CMD_NONE	2
122 #define	CMD_AMBIGUOUS	3
123 
124 /*
125  * Exported global variables
126  */
127 bool		db_cmd_loop_done;
128 label_t		*db_recover;
129 db_addr_t	db_dot;
130 db_addr_t	db_last_addr;
131 db_addr_t	db_prev;
132 db_addr_t	db_next;
133 
134 
135 /*
136   New DDB api for adding and removing commands uses three lists, because
137   we use two types of commands
138   a) standard commands without subcommands -> reboot
139   b) show commands which are subcommands of show command -> show aio_jobs
140   c) if defined machine specific commands
141 
142   ddb_add_cmd, ddb_rem_cmd use type (DDB_SHOW_CMD||DDB_BASE_CMD)argument to
143   add them to representativ lists.
144 */
145 
146 static const struct db_command db_command_table[];
147 static const struct db_command db_show_cmds[];
148 #ifdef DB_MACHINE_COMMANDS
149 static const struct db_command db_machine_command_table[];
150 #endif
151 
152 /* the global queue of all command tables */
153 TAILQ_HEAD(db_cmd_tbl_en_head, db_cmd_tbl_en);
154 
155 /* TAILQ entry used to register command tables */
156 struct db_cmd_tbl_en {
157 	const struct db_command *db_cmd;	/* cmd table */
158 	TAILQ_ENTRY(db_cmd_tbl_en) db_cmd_next;
159 };
160 
161 /* head of base commands list */
162 static struct db_cmd_tbl_en_head db_base_cmd_list =
163 	TAILQ_HEAD_INITIALIZER(db_base_cmd_list);
164 static struct db_cmd_tbl_en db_base_cmd_builtins =
165      { .db_cmd = db_command_table };
166 
167 /* head of show commands list */
168 static struct db_cmd_tbl_en_head db_show_cmd_list =
169 	TAILQ_HEAD_INITIALIZER(db_show_cmd_list);
170 static struct db_cmd_tbl_en db_show_cmd_builtins =
171      { .db_cmd = db_show_cmds };
172 
173 /* head of machine commands list */
174 static struct db_cmd_tbl_en_head db_mach_cmd_list =
175 	TAILQ_HEAD_INITIALIZER(db_mach_cmd_list);
176 #ifdef DB_MACHINE_COMMANDS
177 static struct db_cmd_tbl_en db_mach_cmd_builtins =
178      { .db_cmd = db_machine_command_table };
179 #endif
180 
181 /*
182  * if 'ed' style: 'dot' is set at start of last item printed,
183  * and '+' points to next line.
184  * Otherwise: 'dot' points to next item, '..' points to last.
185  */
186 static bool	 db_ed_style = true;
187 
188 static void	db_init_commands(void);
189 static int	db_register_tbl_entry(uint8_t type,
190     struct db_cmd_tbl_en *list_ent);
191 static void	db_cmd_list(const struct db_cmd_tbl_en_head *);
192 static int	db_cmd_search(const char *, const struct db_command *,
193     const struct db_command **);
194 static void	db_command(const struct db_command **);
195 static void	db_buf_print_cmd(db_expr_t, bool, db_expr_t, const char *);
196 static void	db_event_print_cmd(db_expr_t, bool, db_expr_t, const char *);
197 static void	db_fncall(db_expr_t, bool, db_expr_t, const char *);
198 static int      db_get_list_type(const char *);
199 static void     db_help_print_cmd(db_expr_t, bool, db_expr_t, const char *);
200 static void	db_lock_print_cmd(db_expr_t, bool, db_expr_t, const char *);
201 static void	db_mount_print_cmd(db_expr_t, bool, db_expr_t, const char *);
202 static void	db_mbuf_print_cmd(db_expr_t, bool, db_expr_t, const char *);
203 static void	db_malloc_print_cmd(db_expr_t, bool, db_expr_t, const char *);
204 static void	db_map_print_cmd(db_expr_t, bool, db_expr_t, const char *);
205 static void	db_namecache_print_cmd(db_expr_t, bool, db_expr_t,
206 		    const char *);
207 static void	db_object_print_cmd(db_expr_t, bool, db_expr_t, const char *);
208 static void	db_page_print_cmd(db_expr_t, bool, db_expr_t, const char *);
209 static void	db_show_all_pages(db_expr_t, bool, db_expr_t, const char *);
210 static void	db_pool_print_cmd(db_expr_t, bool, db_expr_t, const char *);
211 static void	db_reboot_cmd(db_expr_t, bool, db_expr_t, const char *);
212 static void	db_sifting_cmd(db_expr_t, bool, db_expr_t, const char *);
213 static void	db_stack_trace_cmd(db_expr_t, bool, db_expr_t, const char *);
214 static void	db_sync_cmd(db_expr_t, bool, db_expr_t, const char *);
215 static void	db_whatis_cmd(db_expr_t, bool, db_expr_t, const char *);
216 static void	db_uvmexp_print_cmd(db_expr_t, bool, db_expr_t, const char *);
217 static void	db_vnode_print_cmd(db_expr_t, bool, db_expr_t, const char *);
218 
219 static const struct db_command db_show_cmds[] = {
220 	/*added from all sub cmds*/
221 	{ DDB_ADD_CMD("callout",  db_show_callout,
222 	    0 ,"List all used callout functions.",NULL,NULL) },
223 	{ DDB_ADD_CMD("pages",	db_show_all_pages,
224 	    0 ,"List all used memory pages.",NULL,NULL) },
225 	{ DDB_ADD_CMD("procs",	db_show_all_procs,
226 	    0 ,"List all processes.",NULL,NULL) },
227 	{ DDB_ADD_CMD("pools",	db_show_all_pools,
228 	    0 ,"Show all poolS",NULL,NULL) },
229 	/*added from all sub cmds*/
230 	{ DDB_ADD_CMD("aio_jobs",	db_show_aio_jobs,	0,
231 	    "Show aio jobs",NULL,NULL) },
232 	{ DDB_ADD_CMD("all",	NULL,
233 	    CS_COMPAT, NULL,NULL,NULL) },
234 #if defined(INET) && (NARP > 0)
235 	{ DDB_ADD_CMD("arptab",	db_show_arptab,		0,NULL,NULL,NULL) },
236 #endif
237 	{ DDB_ADD_CMD("breaks",	db_listbreak_cmd, 	0,
238 	    "Display all breaks.",NULL,NULL) },
239 	{ DDB_ADD_CMD("buf",	db_buf_print_cmd,	0,
240 	    "Print the struct buf at address.", "[/f] address",NULL) },
241 	{ DDB_ADD_CMD("event",	db_event_print_cmd,	0,
242 	    "Print all the non-zero evcnt(9) event counters.", "[/f]",NULL) },
243 	{ DDB_ADD_CMD("lock",	db_lock_print_cmd,	0,NULL,NULL,NULL) },
244 	{ DDB_ADD_CMD("malloc",	db_malloc_print_cmd,0,NULL,NULL,NULL) },
245 	{ DDB_ADD_CMD("map",	db_map_print_cmd,	0,
246 	    "Print the vm_map at address.", "[/f] address",NULL) },
247 	{ DDB_ADD_CMD("mount",	db_mount_print_cmd,	0,
248 	    "Print the mount structure at address.", "[/f] address",NULL) },
249 	{ DDB_ADD_CMD("mbuf",	db_mbuf_print_cmd,	0,NULL,NULL,
250 	    "-c prints all mbuf chains") },
251 	{ DDB_ADD_CMD("ncache",	db_namecache_print_cmd,	0,
252 	    "Dump the namecache list.", "address",NULL) },
253 	{ DDB_ADD_CMD("object",	db_object_print_cmd,	0,
254 	    "Print the vm_object at address.", "[/f] address",NULL) },
255 	{ DDB_ADD_CMD("page",	db_page_print_cmd,	0,
256 	    "Print the vm_page at address.", "[/f] address",NULL) },
257 	{ DDB_ADD_CMD("pool",	db_pool_print_cmd,	0,
258 	    "Print the pool at address.", "[/clp] address",NULL) },
259 	{ DDB_ADD_CMD("registers",	db_show_regs,		0,
260 	    "Display the register set.", "[/u]",NULL) },
261 	{ DDB_ADD_CMD("sched_qs",	db_show_sched_qs,	0,
262 	    "Print the state of the scheduler's run queues.",
263 	    NULL,NULL) },
264 	{ DDB_ADD_CMD("uvmexp",	db_uvmexp_print_cmd, 0,
265 	    "Print a selection of UVM counters and statistics.",
266 	    NULL,NULL) },
267 	{ DDB_ADD_CMD("vnode",	db_vnode_print_cmd,	0,
268 	    "Print the vnode at address.", "[/f] address",NULL) },
269 	{ DDB_ADD_CMD("watches",	db_listwatch_cmd, 	0,
270 	    "Display all watchpoints.", NULL,NULL) },
271 	{ DDB_ADD_CMD(NULL,		NULL,			0,NULL,NULL,NULL) }
272 };
273 
274 /* arch/<arch>/<arch>/db_interface.c */
275 #ifdef DB_MACHINE_COMMANDS
276 extern const struct db_command db_machine_command_table[];
277 #endif
278 
279 static const struct db_command db_command_table[] = {
280 	{ DDB_ADD_CMD("b",		db_breakpoint_cmd,	0,
281 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
282 	{ DDB_ADD_CMD("break",	db_breakpoint_cmd,	0,
283 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
284 	{ DDB_ADD_CMD("bt",		db_stack_trace_cmd,	0,
285 	    "Show backtrace.", "See help trace.",NULL) },
286 	{ DDB_ADD_CMD("c",		db_continue_cmd,	0,
287 	    "Continue execution.", "[/c]",NULL) },
288 	{ DDB_ADD_CMD("call",	db_fncall,		CS_OWN,
289 	    "Call the function", "address[(expression[,...])]",NULL) },
290 	{ DDB_ADD_CMD("callout",	db_show_callout,	0, NULL,
291 	    NULL,NULL ) },
292 	{ DDB_ADD_CMD("continue",	db_continue_cmd,	0,
293 	    "Continue execution.", "[/c]",NULL) },
294 	{ DDB_ADD_CMD("d",		db_delete_cmd,		0,
295 	    "Delete a breakpoint.", "address | #number",NULL) },
296 	{ DDB_ADD_CMD("delete",	db_delete_cmd,		0,
297 	    "Delete a breakpoint.", "address | #number",NULL) },
298 	{ DDB_ADD_CMD("dmesg",	db_dmesg,		0,
299 	    "Show kernel message buffer.", "[count]",NULL) },
300 	{ DDB_ADD_CMD("dwatch",	db_deletewatch_cmd,	0,
301 	    "Delete the watchpoint.", "address",NULL) },
302 	{ DDB_ADD_CMD("examine",	db_examine_cmd,		CS_SET_DOT,
303 	    "Display the address locations.",
304 	    "[/modifier] address[,count]",NULL) },
305 	{ DDB_ADD_CMD("help",   db_help_print_cmd, CS_OWN|CS_NOREPEAT,
306 	    "Display help about commands",
307 	    "Use other commands as arguments.",NULL) },
308 	{ DDB_ADD_CMD("kill",	db_kill_proc,		CS_OWN,
309 	    "Send a signal to the process","pid[,signal_number]",
310 	    "   pid:\t\t\tthe process id (may need 0t prefix for decimal)\n"
311 	    "   signal_number:\tthe signal to send") },
312 #ifdef KGDB
313 	{ DDB_ADD_CMD("kgdb",	db_kgdb_cmd,	0,	NULL,NULL,NULL) },
314 #endif
315 	{ DDB_ADD_CMD("machine",NULL,CS_MACH,
316 	    "Architecture specific functions.",NULL,NULL) },
317 	{ DDB_ADD_CMD("match",	db_trace_until_matching_cmd,0,
318 	    "Stop at the matching return instruction.","See help next",NULL) },
319 	{ DDB_ADD_CMD("next",	db_trace_until_matching_cmd,0,
320 	    "Stop at the matching return instruction.","[/p]",NULL) },
321 	{ DDB_ADD_CMD("p",		db_print_cmd,		0,
322 	    "Print address according to the format.",
323 	    "[/axzodurc] address [address ...]",NULL) },
324 	{ DDB_ADD_CMD("print",	db_print_cmd,		0,
325 	    "Print address according to the format.",
326 	    "[/axzodurc] address [address ...]",NULL) },
327 	{ DDB_ADD_CMD("ps",		db_show_all_procs,	0,
328 	    "Print all processes.","See show all procs",NULL) },
329 	{ DDB_ADD_CMD("reboot",	db_reboot_cmd,		CS_OWN,
330 	    "Reboot","0x1  RB_ASKNAME, 0x2 RB_SINGLE, 0x4 RB_NOSYNC, 0x8 RB_HALT,"
331 	    "0x40 RB_KDB, 0x100 RB_DUMP, 0x808 RB_POWERDOWN",NULL) },
332 	{ DDB_ADD_CMD("s",		db_single_step_cmd,	0,
333 	    "Single-step count times.","[/p] [,count]",NULL) },
334 	{ DDB_ADD_CMD("search",	db_search_cmd,		CS_OWN|CS_SET_DOT,
335 	    "Search memory from address for value.",
336 	    "[/bhl] address value [mask] [,count]",NULL) },
337 	{ DDB_ADD_CMD("set",	db_set_cmd,		CS_OWN,
338 	    "Set the named variable","$variable [=] expression",NULL) },
339 	{ DDB_ADD_CMD("show",	NULL, CS_SHOW,
340 	    "Show kernel stats.", NULL,NULL) },
341 	{ DDB_ADD_CMD("sifting",	db_sifting_cmd,		CS_OWN,
342 	    "Search the symbol tables ","[/F] string",NULL) },
343 	{ DDB_ADD_CMD("step",	db_single_step_cmd,	0,
344 	    "Single-step count times.","[/p] [,count]",NULL) },
345 	{ DDB_ADD_CMD("sync",	db_sync_cmd,		CS_OWN,
346 	    "Force a crash dump, and then reboot.",NULL,NULL) },
347 	{ DDB_ADD_CMD("trace",	db_stack_trace_cmd,	0,
348 	    "Stack trace from frame-address.",
349 	    "[/u[l]] [frame-address][,count]",NULL) },
350 	{ DDB_ADD_CMD("until",	db_trace_until_call_cmd,0,
351 	    "Stop at the next call or return instruction.","[/p]",NULL) },
352 	{ DDB_ADD_CMD("w",		db_write_cmd,		CS_MORE|CS_SET_DOT,
353 	    "Write the expressions at succeeding locations.",
354 	    "[/bhl] address expression [expression ...]",NULL) },
355 	{ DDB_ADD_CMD("watch",	db_watchpoint_cmd,	CS_MORE,
356 	    "Set a watchpoint for a region. ","address[,size]",NULL) },
357 	{ DDB_ADD_CMD("whatis",	db_whatis_cmd, 0,
358 	    "Describe what an address is", "address", NULL) },
359 	{ DDB_ADD_CMD("write",	db_write_cmd,		CS_MORE|CS_SET_DOT,
360 	    "Write the expressions at succeeding locations.",
361 	    "[/bhl] address expression [expression ...]",NULL) },
362 	{ DDB_ADD_CMD("x",		db_examine_cmd,		CS_SET_DOT,
363 	    "Display the address locations.",
364 	    "[/modifier] address[,count]",NULL) },
365 	{ DDB_ADD_CMD(NULL, 	NULL,		   0, NULL, NULL, NULL) }
366 };
367 
368 static const struct db_command	*db_last_command = NULL;
369 #if defined(DDB_COMMANDONENTER)
370 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = ___STRING(DDB_COMMANDONENTER);
371 #else /* defined(DDB_COMMANDONENTER) */
372 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = "";
373 #endif /* defined(DDB_COMMANDONENTER) */
374 #define	DB_LINE_SEP	';'
375 
376 /*
377  * Utility routine - discard tokens through end-of-line.
378  */
379 void
380 db_skip_to_eol(void)
381 {
382 	int t;
383 
384 	do {
385 		t = db_read_token();
386 	} while (t != tEOL);
387 }
388 
389 void
390 db_error(const char *s)
391 {
392 
393 	if (s)
394 		db_printf("%s", s);
395 	db_flush_lex();
396 	longjmp(db_recover);
397 }
398 
399 /*Execute commandlist after ddb start
400  *This function goes through the command list created from commands and ';'
401  */
402 
403 static void
404 db_execute_commandlist(const char *cmdlist)
405 {
406 	const char *cmd = cmdlist;
407 	const struct db_command	*dummy = NULL;
408 
409 	while (*cmd != '\0') {
410 		const char *ep = cmd;
411 
412 		while (*ep != '\0' && *ep != DB_LINE_SEP) {
413 			ep++;
414 		}
415 		db_set_line(cmd, ep);
416 		db_command(&dummy);
417 		cmd = ep;
418 		if (*cmd == DB_LINE_SEP) {
419 			cmd++;
420 		}
421 	}
422 }
423 
424 /*Initialize ddb command tables*/
425 void
426 db_init_commands(void)
427 {
428 	static bool done = false;
429 
430 	if (done) return;
431 	done = true;
432 
433 	/* register command tables */
434 	(void)db_register_tbl_entry(DDB_BASE_CMD, &db_base_cmd_builtins);
435 #ifdef DB_MACHINE_COMMANDS
436 	(void)db_register_tbl_entry(DDB_MACH_CMD, &db_mach_cmd_builtins);
437 #endif
438 	(void)db_register_tbl_entry(DDB_SHOW_CMD, &db_show_cmd_builtins);
439 }
440 
441 
442 /*
443  * Add command table to the specified list
444  * Arg:
445  * int type specifies type of command table DDB_SHOW_CMD|DDB_BASE_CMD|DDB_MAC_CMD
446  * *cmd_tbl poiter to static allocated db_command table
447  *
448  *Command table must be NULL terminated array of struct db_command
449  */
450 int
451 db_register_tbl(uint8_t type, const struct db_command *cmd_tbl)
452 {
453 	struct db_cmd_tbl_en *list_ent;
454 
455 	if (cmd_tbl->name == 0)
456 		/* empty list - ignore */
457 		return 0;
458 
459 	/* force builtin commands to be registered first */
460 	db_init_commands();
461 
462 	/* now create a list entry for this table */
463 	list_ent = malloc(sizeof(struct db_cmd_tbl_en), M_TEMP, M_ZERO);
464 	if (list_ent == NULL)
465 		return ENOMEM;
466 	list_ent->db_cmd=cmd_tbl;
467 
468 	/* and register it */
469 	return db_register_tbl_entry(type, list_ent);
470 }
471 
472 static int
473 db_register_tbl_entry(uint8_t type, struct db_cmd_tbl_en *list_ent)
474 {
475 	struct db_cmd_tbl_en_head *list;
476 
477 	switch(type) {
478 	case DDB_BASE_CMD:
479 		list = &db_base_cmd_list;
480 		break;
481 	case DDB_SHOW_CMD:
482 		list = &db_show_cmd_list;
483 		break;
484 	case DDB_MACH_CMD:
485 		list = &db_mach_cmd_list;
486 		break;
487 	default:
488 		return ENOENT;
489 	}
490 
491 	TAILQ_INSERT_TAIL(list, list_ent, db_cmd_next);
492 
493 	return 0;
494 }
495 
496 /*
497  * Remove command table specified with db_cmd address == cmd_tbl
498  */
499 int
500 db_unregister_tbl(uint8_t type,const struct db_command *cmd_tbl)
501 {
502 	struct db_cmd_tbl_en *list_ent;
503 	struct db_cmd_tbl_en_head *list;
504 
505 	/* find list on which the entry should live */
506 	switch (type) {
507 	case DDB_BASE_CMD:
508 		list=&db_base_cmd_list;
509 		break;
510 	case DDB_SHOW_CMD:
511 		list=&db_show_cmd_list;
512 		break;
513 	case DDB_MACH_CMD:
514 		list=&db_mach_cmd_list;
515 		break;
516 	default:
517 		return EINVAL;
518 	}
519 
520 	TAILQ_FOREACH (list_ent,list,db_cmd_next) {
521 		if (list_ent->db_cmd == cmd_tbl){
522 			TAILQ_REMOVE(list,
523 			    list_ent,db_cmd_next);
524 			free(list_ent,M_TEMP);
525 			return 0;
526 		}
527 	}
528 	return ENOENT;
529 }
530 
531 /*This function is called from machine trap code.*/
532 void
533 db_command_loop(void)
534 {
535 
536 	label_t	db_jmpbuf;
537 	label_t	*savejmp;
538 
539 	/*
540 	 * Initialize 'prev' and 'next' to dot.
541 	 */
542 	db_prev = db_dot;
543 	db_next = db_dot;
544 
545 	db_cmd_loop_done = false;
546 
547 	/*Init default command tables add machine, base,
548 	  show command tables to the list*/
549 	db_init_commands();
550 
551 	/*save context for return from ddb*/
552 	savejmp = db_recover;
553 	db_recover = &db_jmpbuf;
554 	(void) setjmp(&db_jmpbuf);
555 
556 	/*Execute default ddb start commands*/
557 	db_execute_commandlist(db_cmd_on_enter);
558 
559 	(void) setjmp(&db_jmpbuf);
560 	while (!db_cmd_loop_done) {
561 		if (db_print_position() != 0)
562 			db_printf("\n");
563 		db_output_line = 0;
564 
565 
566 #ifdef MULTIPROCESSOR
567 		db_printf("db{%ld}> ", (long)cpu_number());
568 #else
569 		db_printf("db> ");
570 #endif
571 		(void) db_read_line();
572 
573 		db_command(&db_last_command);
574 	}
575 
576 	db_recover = savejmp;
577 }
578 
579 /*
580  * Search for command table for command prefix
581  * ret: CMD_UNIQUE    -> completely matches command
582  *      CMD_FOUND     -> matches prefix of single command
583  *      CMD_AMBIGIOUS -> matches prefix of more than one command
584  *      CMD_NONE      -> command not found
585  */
586 static int
587 db_cmd_search(const char *name,const struct db_command *table,
588     const struct db_command **cmdp)
589 {
590 
591 	const struct db_command	*cmd;
592 	int result;
593 
594 	result = CMD_NONE;
595 	*cmdp = NULL;
596 	for (cmd = table; cmd->name != 0; cmd++) {
597 		const char *lp;
598 		const char *rp;
599 
600 		lp = name;
601 		rp = cmd->name;
602 		while (*lp != '\0' && *lp == *rp) {
603 			rp++;
604 			lp++;
605 		}
606 
607 		if (*lp != '\0') /* mismatch or extra chars in name */
608 			continue;
609 
610 		if (*rp == '\0') { /* complete match */
611 			*cmdp = cmd;
612 			return (CMD_UNIQUE);
613 		}
614 
615 		/* prefix match: end of name, not end of command */
616 		if (result == CMD_NONE) {
617 			result = CMD_FOUND;
618 			*cmdp = cmd;
619 		}
620 		else if (result == CMD_FOUND) {
621 			result = CMD_AMBIGUOUS;
622 			*cmdp = NULL;
623 		}
624 	}
625 
626 	return (result);
627 }
628 
629 /*
630  *List commands to the console.
631  */
632 static void
633 db_cmd_list(const struct db_cmd_tbl_en_head *list)
634 {
635 
636 	struct db_cmd_tbl_en *list_ent;
637 	const struct db_command *table;
638 	size_t		i, j, w, columns, lines, numcmds, width=0;
639 	const char	*p;
640 
641 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
642 		table = list_ent->db_cmd;
643 		for (i = 0; table[i].name != NULL; i++) {
644 			w = strlen(table[i].name);
645 			if (w > width)
646 				width = w;
647 		}
648 	}
649 
650 	width = DB_NEXT_TAB(width);
651 
652 	columns = db_max_width / width;
653 	if (columns == 0)
654 		columns = 1;
655 
656 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
657 		table = list_ent->db_cmd;
658 
659 		for (numcmds = 0; table[numcmds].name != NULL; numcmds++)
660 			;
661 		lines = (numcmds + columns - 1) / columns;
662 
663 		for (i = 0; i < lines; i++) {
664 			for (j = 0; j < columns; j++) {
665 				p = table[j * lines + i].name;
666 				if (p)
667 					db_printf("%s", p);
668 				if (j * lines + i + lines >= numcmds) {
669 					db_putchar('\n');
670 					break;
671 				}
672 				if (p) {
673 					w = strlen(p);
674 					while (w < width) {
675 						w = DB_NEXT_TAB(w);
676 						db_putchar('\t');
677 					}
678 				}
679 			}
680 		}
681 	}
682 	return;
683 }
684 
685 /*
686  *Returns type of list for command with name *name.
687  */
688 static int
689 db_get_list_type(const char *name)
690 {
691 
692 	const struct db_command    *cmd;
693 	struct db_cmd_tbl_en *list_ent;
694 	int error,ret=-1;
695 
696 	/* search for the command name */
697 	TAILQ_FOREACH(list_ent,&db_base_cmd_list,db_cmd_next) {
698 		/*
699 		 * cmd_search returns CMD_UNIQUE, CMD_FOUND ...
700 		 * CMD_UNIQUE when name was completly matched to cmd->name
701 		 * CMD_FOUND  when name was only partially matched to cmd->name
702 		 * CMD_NONE   command not found in a list
703 		 * CMD_AMBIGIOUS ->more partialy matches
704 		 */
705 
706 		error = db_cmd_search(name, list_ent->db_cmd, &cmd);
707 
708 		if (error == CMD_UNIQUE) {
709 			/* exact match found */
710 			if (cmd->flag == CS_SHOW) {
711 				ret = DDB_SHOW_CMD;
712 				break;
713 			}
714 			if (cmd->flag == CS_MACH) {
715 				ret = DDB_MACH_CMD;
716 				break;
717 			} else {
718 				ret = DDB_BASE_CMD;
719 				break;
720 			}
721 
722 		} else if (error == CMD_FOUND) {
723 			/*
724 			 * partial match, search will continue, but
725 			 * note current result in case we won't
726 			 * find anything better.
727 			 */
728 			if (cmd->flag == CS_SHOW)
729 				ret = DDB_SHOW_CMD;
730 			else if (cmd->flag == CS_MACH)
731 				ret = DDB_MACH_CMD;
732 			else
733 				ret = DDB_BASE_CMD;
734 		}
735 	}
736 
737 	return ret;
738 }
739 
740 /*
741  *Parse command line and execute apropriate function.
742  */
743 static void
744 db_command(const struct db_command **last_cmdp)
745 {
746 	const struct db_command *command;
747 	struct db_cmd_tbl_en *list_ent;
748 	struct db_cmd_tbl_en_head *list;
749 
750 	int		t;
751 	int		result;
752 
753 	char		modif[TOK_STRING_SIZE];
754 	db_expr_t	addr, count;
755 	bool		have_addr = false;
756 
757 	static db_expr_t last_count = 0;
758 
759 	command = NULL;	/* XXX gcc */
760 
761 	t = db_read_token();
762 	if ((t == tEOL) || (t == tCOMMA)) {
763 		/*
764 		 * An empty line repeats last command, at 'next'.
765 		 * Only a count repeats the last command with the new count.
766 		 */
767 		command = *last_cmdp;
768 
769 		if (!command)
770 			return;
771 
772 		addr = (db_expr_t)db_next;
773 		if (t == tCOMMA) {
774 			if (!db_expression(&count)) {
775 				db_printf("Count missing\n");
776 				db_flush_lex();
777 				return;
778 			}
779 		} else
780 			count = last_count;
781 		have_addr = false;
782 		modif[0] = '\0';
783 		db_skip_to_eol();
784 
785 	} else if (t == tEXCL) {
786 		db_fncall(0, 0, 0, NULL);
787 		return;
788 
789 	} else if (t != tIDENT) {
790 		db_printf("?\n");
791 		db_flush_lex();
792 		return;
793 
794 	} else {
795 
796 		switch(db_get_list_type(db_tok_string)) {
797 
798 		case DDB_BASE_CMD:
799 			list = &db_base_cmd_list;
800 			break;
801 
802 		case DDB_SHOW_CMD:
803 			list = &db_show_cmd_list;
804 			/* need to read show subcommand if show command list
805 			   is used. */
806 			t = db_read_token();
807 
808 			if (t != tIDENT) {
809 				/* if only show command is executed, print
810 				   all subcommands */
811 				db_cmd_list(list);
812 				db_flush_lex();
813 				return;
814 			}
815 			break;
816 		case DDB_MACH_CMD:
817 			list = &db_mach_cmd_list;
818 			/* need to read machine subcommand if
819 			  machine level 2 command list is used. */
820 			t = db_read_token();
821 
822 			if (t != tIDENT) {
823 				/* if only show command is executed, print
824 				   all subcommands */
825 				db_cmd_list(list);
826 				db_flush_lex();
827 				return;
828 			}
829 			break;
830 		default:
831 			db_printf("No such command\n");
832 			db_flush_lex();
833 			return;
834 		}
835 
836  COMPAT_RET:
837 		TAILQ_FOREACH(list_ent, list, db_cmd_next) {
838 			result = db_cmd_search(db_tok_string, list_ent->db_cmd,
839 			    &command);
840 
841 			/* after CMD_UNIQUE in cmd_list only a single command
842 			   name is possible */
843 			if (result == CMD_UNIQUE)
844 				break;
845 
846 		}
847 
848                 /* check compatibility flag */
849 		if (command && command->flag & CS_COMPAT){
850 			t = db_read_token();
851 			if (t != tIDENT) {
852 					db_cmd_list(list);
853 					db_flush_lex();
854 					return;
855 			}
856 
857 			/* support only level 2 commands here */
858 			goto COMPAT_RET;
859 		}
860 
861 		if (!command) {
862 			db_printf("No such command\n");
863 			db_flush_lex();
864 			return;
865 		}
866 
867 		if ((command->flag & CS_OWN) == 0) {
868 
869 			/*
870 			 * Standard syntax:
871 			 * command [/modifier] [addr] [,count]
872 			 */
873 			t = db_read_token(); /* get modifier */
874 			if (t == tSLASH) {
875 				t = db_read_token();
876 				if (t != tIDENT) {
877 					db_printf("Bad modifier\n");
878 					db_flush_lex();
879 					return;
880 				}
881 				/* save modifier */
882 				strlcpy(modif, db_tok_string, sizeof(modif));
883 
884 			} else {
885 				db_unread_token(t);
886 				modif[0] = '\0';
887 			}
888 
889 			if (db_expression(&addr)) { /*get address*/
890 				db_dot = (db_addr_t) addr;
891 				db_last_addr = db_dot;
892 				have_addr = true;
893 			} else {
894 				addr = (db_expr_t) db_dot;
895 				have_addr = false;
896 			}
897 
898 			t = db_read_token();
899 			if (t == tCOMMA) { /*Get count*/
900 				if (!db_expression(&count)) {
901 					db_printf("Count missing\n");
902 					db_flush_lex();
903 					return;
904 				}
905 			} else {
906 				db_unread_token(t);
907 				count = -1;
908 			}
909 			if ((command->flag & CS_MORE) == 0) {
910 				db_skip_to_eol();
911 			}
912 		}
913 	}
914 
915 	if (command->flag & CS_NOREPEAT) {
916 		*last_cmdp = NULL;
917 		last_count = 0;
918 	} else {
919 		*last_cmdp = command;
920 		last_count = count;
921 	}
922 
923 	if (command != NULL) {
924 		/*
925 		 * Execute the command.
926 		 */
927 		if (command->fcn != NULL)
928 			(*command->fcn)(addr, have_addr, count, modif);
929 
930 		if (command->flag & CS_SET_DOT) {
931 			/*
932 			 * If command changes dot, set dot to
933 			 * previous address displayed (if 'ed' style).
934 			 */
935 			if (db_ed_style)
936 				db_dot = db_prev;
937 			else
938 				db_dot = db_next;
939 		} else {
940 			/*
941 			 * If command does not change dot,
942 			 * set 'next' location to be the same.
943 			 */
944 			db_next = db_dot;
945 		}
946 	}
947 }
948 
949 /*
950  * Print help for commands
951  */
952 static void
953 db_help_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
954     const char *modif)
955 {
956 
957 	const struct db_cmd_tbl_en_head *list;
958 	const struct db_cmd_tbl_en *list_ent;
959 	const struct db_command *help = NULL;
960 	int t, result;
961 
962 	t = db_read_token();
963 	/* is there another command after the "help"? */
964 	if (t == tIDENT){
965 
966 		switch(db_get_list_type(db_tok_string)) {
967 
968 		case DDB_BASE_CMD:
969 			list=&db_base_cmd_list;
970 			break;
971 		case DDB_SHOW_CMD:
972 			list=&db_show_cmd_list;
973 			/* read the show subcommand */
974 			t = db_read_token();
975 
976 			if (t != tIDENT) {
977 				/* no subcommand, print the list */
978 				db_cmd_list(list);
979 				db_flush_lex();
980 				return;
981 			}
982 
983 			break;
984 		case DDB_MACH_CMD:
985 			list=&db_mach_cmd_list;
986 			/* read machine subcommand */
987 			t = db_read_token();
988 
989 			if (t != tIDENT) {
990 				/* no subcommand - just print the list */
991 				db_cmd_list(list);
992 				db_flush_lex();
993 				return;
994 			}
995 			break;
996 
997 		default:
998 			db_printf("No such command\n");
999 			db_flush_lex();
1000 			return;
1001 		}
1002  COMPAT_RET:
1003 		TAILQ_FOREACH(list_ent,list,db_cmd_next){
1004 			result = db_cmd_search(db_tok_string, list_ent->db_cmd,
1005 					&help);
1006 			/* after CMD_UNIQUE only a single command
1007 			   name is possible */
1008 			if (result == CMD_UNIQUE)
1009 				break;
1010 		}
1011 #ifdef DDB_VERBOSE_HELP
1012 		/*print help*/
1013 
1014 		db_printf("Command: %s\n",help->name);
1015 
1016 		if (help->cmd_descr != NULL)
1017 			db_printf(" Description: %s\n",help->cmd_descr);
1018 
1019 		if (help->cmd_arg != NULL)
1020 			db_printf(" Arguments: %s\n",help->cmd_arg);
1021 
1022 		if (help->cmd_arg_help != NULL)
1023 			db_printf(" Arguments description:\n%s\n",
1024 			    help->cmd_arg_help);
1025 
1026 		if ((help->cmd_arg == NULL) && (help->cmd_descr == NULL))
1027 			db_printf("%s Doesn't have any help message included.\n",
1028 			    help->name);
1029 #endif
1030 		/* check compatibility flag */
1031 		/*
1032 		 * The "show all" command table has been merged with the
1033 		 * "show" command table - but we want to keep the old UI
1034 		 * available. So if we find a CS_COMPAT entry, we read
1035 		 * the next token and try again.
1036 		 */
1037 		if (help->flag == CS_COMPAT){
1038 			t = db_read_token();
1039 
1040 			if (t != tIDENT){
1041 				db_cmd_list(list);
1042 				db_flush_lex();
1043 				return;
1044 			}
1045 
1046 			goto COMPAT_RET;
1047 			/* support only level 2 commands here */
1048 		} else {
1049 			db_skip_to_eol();
1050 		}
1051 
1052 	} else /* t != tIDENT */
1053 		/* print base commands */
1054 		db_cmd_list(&db_base_cmd_list);
1055 
1056 	return;
1057 }
1058 
1059 /*ARGSUSED*/
1060 static void
1061 db_map_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
1062     const char *modif)
1063 {
1064 	bool full = false;
1065 
1066 	if (modif[0] == 'f')
1067 		full = true;
1068 
1069 	if (have_addr == false)
1070 		addr = (db_expr_t)(intptr_t) kernel_map;
1071 
1072 	uvm_map_printit((struct vm_map *)(intptr_t) addr, full, db_printf);
1073 }
1074 
1075 /*ARGSUSED*/
1076 static void
1077 db_malloc_print_cmd(db_expr_t addr, bool have_addr,
1078     db_expr_t count, const char *modif)
1079 {
1080 
1081 #ifdef MALLOC_DEBUG
1082 	if (!have_addr)
1083 		addr = 0;
1084 
1085 	debug_malloc_printit(db_printf, (vaddr_t) addr);
1086 #else
1087 	db_printf("The kernel is not built with the MALLOC_DEBUG option.\n");
1088 #endif /* MALLOC_DEBUG */
1089 }
1090 
1091 /*ARGSUSED*/
1092 static void
1093 db_object_print_cmd(db_expr_t addr, bool have_addr,
1094     db_expr_t count, const char *modif)
1095 {
1096 	bool full = false;
1097 
1098 	if (modif[0] == 'f')
1099 		full = true;
1100 
1101 	uvm_object_printit((struct uvm_object *)(intptr_t) addr, full,
1102 	    db_printf);
1103 }
1104 
1105 /*ARGSUSED*/
1106 static void
1107 db_page_print_cmd(db_expr_t addr, bool have_addr,
1108     db_expr_t count, const char *modif)
1109 {
1110 	bool full = false;
1111 
1112 	if (modif[0] == 'f')
1113 		full = true;
1114 
1115 	uvm_page_printit((struct vm_page *)(intptr_t) addr, full, db_printf);
1116 }
1117 
1118 /*ARGSUSED*/
1119 static void
1120 db_show_all_pages(db_expr_t addr, bool have_addr,
1121     db_expr_t count, const char *modif)
1122 {
1123 
1124 	uvm_page_printall(db_printf);
1125 }
1126 
1127 /*ARGSUSED*/
1128 static void
1129 db_buf_print_cmd(db_expr_t addr, bool have_addr,
1130     db_expr_t count, const char *modif)
1131 {
1132 	bool full = false;
1133 
1134 	if (modif[0] == 'f')
1135 		full = true;
1136 
1137 	vfs_buf_print((struct buf *)(intptr_t) addr, full, db_printf);
1138 }
1139 
1140 /*ARGSUSED*/
1141 static void
1142 db_event_print_cmd(db_expr_t addr, bool have_addr,
1143     db_expr_t count, const char *modif)
1144 {
1145 	bool full = false;
1146 
1147 	if (modif[0] == 'f')
1148 		full = true;
1149 
1150 	event_print(full, db_printf);
1151 }
1152 
1153 /*ARGSUSED*/
1154 static void
1155 db_vnode_print_cmd(db_expr_t addr, bool have_addr,
1156     db_expr_t count, const char *modif)
1157 {
1158 	bool full = false;
1159 
1160 	if (modif[0] == 'f')
1161 		full = true;
1162 
1163 	vfs_vnode_print((struct vnode *)(intptr_t) addr, full, db_printf);
1164 }
1165 
1166 static void
1167 db_mount_print_cmd(db_expr_t addr, bool have_addr,
1168     db_expr_t count, const char *modif)
1169 {
1170 	bool full = false;
1171 
1172 	if (modif[0] == 'f')
1173 		full = true;
1174 
1175 	vfs_mount_print((struct mount *)(intptr_t) addr, full, db_printf);
1176 }
1177 
1178 /*ARGSUSED*/
1179 static void
1180 db_mbuf_print_cmd(db_expr_t addr, bool have_addr,
1181     db_expr_t count, const char *modif)
1182 {
1183 
1184 	m_print((const struct mbuf *)(intptr_t) addr, modif, db_printf);
1185 }
1186 
1187 /*ARGSUSED*/
1188 static void
1189 db_pool_print_cmd(db_expr_t addr, bool have_addr,
1190     db_expr_t count, const char *modif)
1191 {
1192 
1193 	pool_printit((struct pool *)(intptr_t) addr, modif, db_printf);
1194 }
1195 
1196 /*ARGSUSED*/
1197 static void
1198 db_namecache_print_cmd(db_expr_t addr, bool have_addr,
1199     db_expr_t count, const char *modif)
1200 {
1201 
1202 	namecache_print((struct vnode *)(intptr_t) addr, db_printf);
1203 }
1204 
1205 /*ARGSUSED*/
1206 static void
1207 db_uvmexp_print_cmd(db_expr_t addr, bool have_addr,
1208     db_expr_t count, const char *modif)
1209 {
1210 
1211 	uvmexp_print(db_printf);
1212 }
1213 
1214 /*ARGSUSED*/
1215 static void
1216 db_lock_print_cmd(db_expr_t addr, bool have_addr,
1217     db_expr_t count, const char *modif)
1218 {
1219 
1220 	lockdebug_lock_print((void *)addr, db_printf);
1221 }
1222 
1223 /*
1224  * Call random function:
1225  * !expr(arg,arg,arg)
1226  */
1227 /*ARGSUSED*/
1228 static void
1229 db_fncall(db_expr_t addr, bool have_addr,
1230     db_expr_t count, const char *modif)
1231 {
1232 	db_expr_t	fn_addr;
1233 #define	MAXARGS		11
1234 	db_expr_t	args[MAXARGS];
1235 	int		nargs = 0;
1236 	db_expr_t	retval;
1237 	db_expr_t	(*func)(db_expr_t, ...);
1238 	int		t;
1239 
1240 	if (!db_expression(&fn_addr)) {
1241 		db_printf("Bad function\n");
1242 		db_flush_lex();
1243 		return;
1244 	}
1245 	func = (db_expr_t (*)(db_expr_t, ...))(intptr_t) fn_addr;
1246 
1247 	t = db_read_token();
1248 	if (t == tLPAREN) {
1249 		if (db_expression(&args[0])) {
1250 			nargs++;
1251 			while ((t = db_read_token()) == tCOMMA) {
1252 				if (nargs == MAXARGS) {
1253 					db_printf("Too many arguments\n");
1254 					db_flush_lex();
1255 					return;
1256 				}
1257 				if (!db_expression(&args[nargs])) {
1258 					db_printf("Argument missing\n");
1259 					db_flush_lex();
1260 					return;
1261 				}
1262 				nargs++;
1263 			}
1264 			db_unread_token(t);
1265 		}
1266 		if (db_read_token() != tRPAREN) {
1267 			db_printf("?\n");
1268 			db_flush_lex();
1269 			return;
1270 		}
1271 	}
1272 	db_skip_to_eol();
1273 
1274 	while (nargs < MAXARGS) {
1275 		args[nargs++] = 0;
1276 	}
1277 
1278 	retval = (*func)(args[0], args[1], args[2], args[3], args[4],
1279 			 args[5], args[6], args[7], args[8], args[9]);
1280 	db_printf("%s\n", db_num_to_str(retval));
1281 }
1282 
1283 static void
1284 db_reboot_cmd(db_expr_t addr, bool have_addr,
1285     db_expr_t count, const char *modif)
1286 {
1287 	db_expr_t bootflags;
1288 
1289 	/* Flags, default to RB_AUTOBOOT */
1290 	if (!db_expression(&bootflags))
1291 		bootflags = (db_expr_t)RB_AUTOBOOT;
1292 	if (db_read_token() != tEOL) {
1293 		db_error("?\n");
1294 		/*NOTREACHED*/
1295 	}
1296 	/*
1297 	 * We are leaving DDB, never to return upward.
1298 	 * Clear db_recover so that we can debug faults in functions
1299 	 * called from cpu_reboot.
1300 	 */
1301 	db_recover = 0;
1302 	cpu_reboot((int)bootflags, NULL);
1303 }
1304 
1305 static void
1306 db_sifting_cmd(db_expr_t addr, bool have_addr,
1307     db_expr_t count, const char *modif)
1308 {
1309 	int	mode, t;
1310 
1311 	t = db_read_token();
1312 	if (t == tSLASH) {
1313 		t = db_read_token();
1314 		if (t != tIDENT) {
1315 			bad_modifier:
1316 			db_printf("Bad modifier\n");
1317 			db_flush_lex();
1318 			return;
1319 		}
1320 		if (!strcmp(db_tok_string, "F"))
1321 			mode = 'F';
1322 		else
1323 			goto bad_modifier;
1324 		t = db_read_token();
1325 	} else
1326 		mode = 0;
1327 
1328 	if (t == tIDENT)
1329 		db_sifting(db_tok_string, mode);
1330 	else {
1331 		db_printf("Bad argument (non-string)\n");
1332 		db_flush_lex();
1333 	}
1334 }
1335 
1336 static void
1337 db_stack_trace_cmd(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
1338 {
1339 	register const char *cp = modif;
1340 	register char c;
1341 	void (*pr)(const char *, ...);
1342 
1343 	pr = db_printf;
1344 	while ((c = *cp++) != 0)
1345 		if (c == 'l')
1346 			pr = printf;
1347 
1348 	if (count == -1)
1349 		count = 65535;
1350 
1351 	db_stack_trace_print(addr, have_addr, count, modif, pr);
1352 }
1353 
1354 static void
1355 db_sync_cmd(db_expr_t addr, bool have_addr,
1356     db_expr_t count, const char *modif)
1357 {
1358 
1359 	/*
1360 	 * We are leaving DDB, never to return upward.
1361 	 * Clear db_recover so that we can debug faults in functions
1362 	 * called from cpu_reboot.
1363 	 */
1364 	db_recover = 0;
1365 	panicstr = "dump forced via kernel debugger";
1366 	cpu_reboot(RB_DUMP, NULL);
1367 }
1368 
1369 /*
1370  * Describe what an address is
1371  */
1372 void
1373 db_whatis_cmd(db_expr_t address, bool have_addr,
1374     db_expr_t count, const char *modif)
1375 {
1376 	const uintptr_t addr = (uintptr_t)address;
1377 
1378 	lwp_whatis(addr, db_printf);
1379 	pool_whatis(addr, db_printf);
1380 	vmem_whatis(addr, db_printf);
1381 	uvm_whatis(addr, db_printf);
1382 }
1383