xref: /netbsd-src/sys/ddb/db_command.c (revision f89f6560d453f5e37386cc7938c072d2f528b9fa)
1 /*	$NetBSD: db_command.c,v 1.144 2015/02/08 19:41:39 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1996, 1997, 1998, 1999, 2002, 2009 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Adam Hamsik, and by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Mach Operating System
34  * Copyright (c) 1991,1990 Carnegie Mellon University
35  * All Rights Reserved.
36  *
37  * Permission to use, copy, modify and distribute this software and its
38  * documentation is hereby granted, provided that both the copyright
39  * notice and this permission notice appear in all copies of the
40  * software, derivative works or modified versions, and any portions
41  * thereof, and that both notices appear in supporting documentation.
42  *
43  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
44  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
45  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
46  *
47  * Carnegie Mellon requests users of this software to return to
48  *
49  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
50  *  School of Computer Science
51  *  Carnegie Mellon University
52  *  Pittsburgh PA 15213-3890
53  *
54  * any improvements or extensions that they make and grant Carnegie the
55  * rights to redistribute these changes.
56  */
57 
58 /*
59  * Command dispatcher.
60  */
61 
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: db_command.c,v 1.144 2015/02/08 19:41:39 christos Exp $");
64 
65 #ifdef _KERNEL_OPT
66 #include "opt_aio.h"
67 #include "opt_ddb.h"
68 #include "opt_kgdb.h"
69 #include "opt_mqueue.h"
70 #include "opt_inet.h"
71 #include "opt_kernhist.h"
72 #include "opt_ddbparam.h"
73 #include "opt_multiprocessor.h"
74 #include "arp.h"
75 #endif
76 
77 #include <sys/param.h>
78 #include <sys/systm.h>
79 #include <sys/reboot.h>
80 #include <sys/device.h>
81 #include <sys/lwp.h>
82 #include <sys/mbuf.h>
83 #include <sys/namei.h>
84 #include <sys/pool.h>
85 #include <sys/proc.h>
86 #include <sys/vnode.h>
87 #include <sys/vmem.h>
88 #include <sys/lockdebug.h>
89 #include <sys/cpu.h>
90 #include <sys/buf.h>
91 #include <sys/module.h>
92 #include <sys/kernhist.h>
93 
94 /*include queue macros*/
95 #include <sys/queue.h>
96 
97 #include <ddb/ddb.h>
98 
99 #include <uvm/uvm_extern.h>
100 #include <uvm/uvm_ddb.h>
101 
102 /*
103  * Results of command search.
104  */
105 #define	CMD_EXACT		0
106 #define	CMD_PREFIX		1
107 #define	CMD_NONE		2
108 #define	CMD_AMBIGUOUS	3
109 
110 /*
111  * Exported global variables
112  */
113 bool		db_cmd_loop_done;
114 label_t		*db_recover;
115 db_addr_t	db_dot;
116 db_addr_t	db_last_addr;
117 db_addr_t	db_prev;
118 db_addr_t	db_next;
119 
120 
121 /*
122  * New DDB api for adding and removing commands uses three lists, because
123  * we use two types of commands
124  * a) standard commands without subcommands -> reboot
125  * b) show commands which are subcommands of show command -> show aio_jobs
126  * c) if defined machine specific commands
127  *
128  * ddb_add_cmd, ddb_rem_cmd use type (DDB_SHOW_CMD||DDB_BASE_CMD)argument to
129  * add them to representativ lists.
130  */
131 
132 static const struct db_command db_command_table[];
133 static const struct db_command db_show_cmds[];
134 
135 #ifdef DB_MACHINE_COMMANDS
136 /* arch/<arch>/<arch>/db_interface.c */
137 extern const struct db_command db_machine_command_table[];
138 #endif
139 
140 /* the global queue of all command tables */
141 TAILQ_HEAD(db_cmd_tbl_en_head, db_cmd_tbl_en);
142 
143 /* TAILQ entry used to register command tables */
144 struct db_cmd_tbl_en {
145 	const struct db_command *db_cmd;	/* cmd table */
146 	TAILQ_ENTRY(db_cmd_tbl_en) db_cmd_next;
147 };
148 
149 /* head of base commands list */
150 static struct db_cmd_tbl_en_head db_base_cmd_list =
151 	TAILQ_HEAD_INITIALIZER(db_base_cmd_list);
152 static struct db_cmd_tbl_en db_base_cmd_builtins =
153      { .db_cmd = db_command_table };
154 
155 /* head of show commands list */
156 static struct db_cmd_tbl_en_head db_show_cmd_list =
157 	TAILQ_HEAD_INITIALIZER(db_show_cmd_list);
158 static struct db_cmd_tbl_en db_show_cmd_builtins =
159      { .db_cmd = db_show_cmds };
160 
161 /* head of machine commands list */
162 static struct db_cmd_tbl_en_head db_mach_cmd_list =
163 	TAILQ_HEAD_INITIALIZER(db_mach_cmd_list);
164 #ifdef DB_MACHINE_COMMANDS
165 static struct db_cmd_tbl_en db_mach_cmd_builtins =
166      { .db_cmd = db_machine_command_table };
167 #endif
168 
169 /*
170  * if 'ed' style: 'dot' is set at start of last item printed,
171  * and '+' points to next line.
172  * Otherwise: 'dot' points to next item, '..' points to last.
173  */
174 static bool	 db_ed_style = true;
175 
176 static void	db_init_commands(void);
177 static int	db_register_tbl_entry(uint8_t type,
178     struct db_cmd_tbl_en *list_ent);
179 static void	db_cmd_list(const struct db_cmd_tbl_en_head *);
180 static int	db_cmd_search(const char *, struct db_cmd_tbl_en_head *,
181 			      const struct db_command **);
182 static int	db_cmd_search_table(const char *, const struct db_command *,
183 				    const struct db_command **);
184 static void	db_cmd_search_failed(char *, int);
185 static const struct db_command *db_read_command(void);
186 static void	db_command(const struct db_command **);
187 static void	db_buf_print_cmd(db_expr_t, bool, db_expr_t, const char *);
188 static void	db_event_print_cmd(db_expr_t, bool, db_expr_t, const char *);
189 static void	db_fncall(db_expr_t, bool, db_expr_t, const char *);
190 static void     db_help_print_cmd(db_expr_t, bool, db_expr_t, const char *);
191 static void	db_lock_print_cmd(db_expr_t, bool, db_expr_t, const char *);
192 static void	db_mount_print_cmd(db_expr_t, bool, db_expr_t, const char *);
193 static void	db_mbuf_print_cmd(db_expr_t, bool, db_expr_t, const char *);
194 static void	db_map_print_cmd(db_expr_t, bool, db_expr_t, const char *);
195 static void	db_namecache_print_cmd(db_expr_t, bool, db_expr_t,
196 		    const char *);
197 static void	db_object_print_cmd(db_expr_t, bool, db_expr_t, const char *);
198 static void	db_page_print_cmd(db_expr_t, bool, db_expr_t, const char *);
199 static void	db_show_all_pages(db_expr_t, bool, db_expr_t, const char *);
200 static void	db_pool_print_cmd(db_expr_t, bool, db_expr_t, const char *);
201 static void	db_reboot_cmd(db_expr_t, bool, db_expr_t, const char *);
202 static void	db_sifting_cmd(db_expr_t, bool, db_expr_t, const char *);
203 static void	db_stack_trace_cmd(db_expr_t, bool, db_expr_t, const char *);
204 static void	db_sync_cmd(db_expr_t, bool, db_expr_t, const char *);
205 static void	db_whatis_cmd(db_expr_t, bool, db_expr_t, const char *);
206 static void	db_uvmexp_print_cmd(db_expr_t, bool, db_expr_t, const char *);
207 #ifdef KERNHIST
208 static void	db_kernhist_print_cmd(db_expr_t, bool, db_expr_t, const char *);
209 #endif
210 static void	db_vnode_print_cmd(db_expr_t, bool, db_expr_t, const char *);
211 static void	db_vmem_print_cmd(db_expr_t, bool, db_expr_t, const char *);
212 
213 static const struct db_command db_show_cmds[] = {
214 	/*added from all sub cmds*/
215 	{ DDB_ADD_CMD("callout",  db_show_callout,
216 	    0 ,"List all used callout functions.",NULL,NULL) },
217 	{ DDB_ADD_CMD("pages",	db_show_all_pages,
218 	    0 ,"List all used memory pages.",NULL,NULL) },
219 	{ DDB_ADD_CMD("proc",	db_show_proc,
220 	    0 ,"Print process information.",NULL,NULL) },
221 	{ DDB_ADD_CMD("procs",	db_show_all_procs,
222 	    0 ,"List all processes.",NULL,NULL) },
223 	{ DDB_ADD_CMD("pools",	db_show_all_pools,
224 	    0 ,"Show all pools",NULL,NULL) },
225 #ifdef AIO
226 	/*added from all sub cmds*/
227 	{ DDB_ADD_CMD("aio_jobs",	db_show_aio_jobs,	0,
228 	    "Show aio jobs",NULL,NULL) },
229 #endif
230 	{ DDB_ADD_CMD("all",	NULL,
231 	    CS_COMPAT, NULL,NULL,NULL) },
232 #if defined(INET) && (NARP > 0)
233 	{ DDB_ADD_CMD("arptab",	db_show_arptab,		0,NULL,NULL,NULL) },
234 #endif
235 #ifdef _KERNEL
236 	{ DDB_ADD_CMD("breaks",	db_listbreak_cmd, 	0,
237 	    "Display all breaks.",NULL,NULL) },
238 #endif
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.", "[/fitm]",NULL) },
243 	{ DDB_ADD_CMD("files", db_show_files_cmd,	0,
244 	    "Print the files open by process at address",
245 	    "[/f] address", NULL) },
246 	{ DDB_ADD_CMD("lock",	db_lock_print_cmd,	0,NULL,NULL,NULL) },
247 	{ DDB_ADD_CMD("map",	db_map_print_cmd,	0,
248 	    "Print the vm_map at address.", "[/f] address",NULL) },
249 	{ DDB_ADD_CMD("module", db_show_module_cmd,	0,
250 	    "Print kernel modules", NULL, NULL) },
251 	{ DDB_ADD_CMD("mount",	db_mount_print_cmd,	0,
252 	    "Print the mount structure at address.", "[/f] address",NULL) },
253 #ifdef MQUEUE
254 	{ DDB_ADD_CMD("mqueue", db_show_mqueue_cmd,	0,
255 	    "Print the message queues", NULL, NULL) },
256 #endif
257 	{ DDB_ADD_CMD("mbuf",	db_mbuf_print_cmd,	0,NULL,NULL,
258 	    "-c prints all mbuf chains") },
259 	{ DDB_ADD_CMD("ncache",	db_namecache_print_cmd,	0,
260 	    "Dump the namecache list.", "address",NULL) },
261 	{ DDB_ADD_CMD("object",	db_object_print_cmd,	0,
262 	    "Print the vm_object at address.", "[/f] address",NULL) },
263 	{ DDB_ADD_CMD("page",	db_page_print_cmd,	0,
264 	    "Print the vm_page at address.", "[/f] address",NULL) },
265 	{ DDB_ADD_CMD("panic",	db_show_panic,	0,
266 	    "Print the current panic string",NULL,NULL) },
267 	{ DDB_ADD_CMD("pool",	db_pool_print_cmd,	0,
268 	    "Print the pool at address.", "[/clp] address",NULL) },
269 	{ DDB_ADD_CMD("registers",	db_show_regs,		0,
270 	    "Display the register set.", "[/u]",NULL) },
271 	{ DDB_ADD_CMD("sched_qs",	db_show_sched_qs,	0,
272 	    "Print the state of the scheduler's run queues.",
273 	    NULL,NULL) },
274 	{ DDB_ADD_CMD("uvmexp",	db_uvmexp_print_cmd, 0,
275 	    "Print a selection of UVM counters and statistics.",
276 	    NULL,NULL) },
277 #ifdef KERNHIST
278 	{ DDB_ADD_CMD("kernhist", db_kernhist_print_cmd, 0,
279 	    "Print the UVM history logs.",
280 	    NULL,NULL) },
281 #endif
282 	{ DDB_ADD_CMD("vnode",	db_vnode_print_cmd,	0,
283 	    "Print the vnode at address.", "[/f] address",NULL) },
284 	{ DDB_ADD_CMD("vmem", db_vmem_print_cmd,	0,
285 	    "Print the vmem usage.", "[/a] address", NULL) },
286 	{ DDB_ADD_CMD("vmems", db_show_all_vmems,	0,
287 	    "Show all vmems.", NULL, NULL) },
288 #ifdef _KERNEL
289 	{ DDB_ADD_CMD("watches",	db_listwatch_cmd, 	0,
290 	    "Display all watchpoints.", NULL,NULL) },
291 #endif
292 	{ DDB_ADD_CMD(NULL,		NULL,			0,NULL,NULL,NULL) }
293 };
294 
295 static const struct db_command db_command_table[] = {
296 	{ DDB_ADD_CMD("b",		db_breakpoint_cmd,	0,
297 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
298 	{ DDB_ADD_CMD("break",	db_breakpoint_cmd,	0,
299 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
300 	{ DDB_ADD_CMD("bt",		db_stack_trace_cmd,	0,
301 	    "Show backtrace.", "See help trace.",NULL) },
302 	{ DDB_ADD_CMD("c",		db_continue_cmd,	0,
303 	    "Continue execution.", "[/c]",NULL) },
304 	{ DDB_ADD_CMD("call",	db_fncall,		CS_OWN,
305 	    "Call the function", "address[(expression[,...])]",NULL) },
306 	{ DDB_ADD_CMD("callout",	db_show_callout,	0, NULL,
307 	    NULL,NULL ) },
308 	{ DDB_ADD_CMD("continue",	db_continue_cmd,	0,
309 	    "Continue execution.", "[/c]",NULL) },
310 	{ DDB_ADD_CMD("d",		db_delete_cmd,		0,
311 	    "Delete a breakpoint.", "address | #number",NULL) },
312 	{ DDB_ADD_CMD("delete",	db_delete_cmd,		0,
313 	    "Delete a breakpoint.", "address | #number",NULL) },
314 	{ DDB_ADD_CMD("dmesg",	db_dmesg,		0,
315 	    "Show kernel message buffer.", "[count]",NULL) },
316 	{ DDB_ADD_CMD("dwatch",	db_deletewatch_cmd,	0,
317 	    "Delete the watchpoint.", "address",NULL) },
318 	{ DDB_ADD_CMD("examine",	db_examine_cmd,		CS_SET_DOT,
319 	    "Display the address locations.",
320 	    "[/modifier] address[,count]",NULL) },
321 	{ DDB_ADD_CMD("exit",		db_continue_cmd,	0,
322 	    "Continue execution.", "[/c]",NULL) },
323 	{ DDB_ADD_CMD("help",   db_help_print_cmd, CS_OWN|CS_NOREPEAT,
324 	    "Display help about commands",
325 	    "Use other commands as arguments.",NULL) },
326 	{ DDB_ADD_CMD("kill",	db_kill_proc,		CS_OWN,
327 	    "Send a signal to the process","pid[,signal_number]",
328 	    "   pid:\t\t\tthe process id (may need 0t prefix for decimal)\n"
329 	    "   signal_number:\tthe signal to send") },
330 #ifdef KGDB
331 	{ DDB_ADD_CMD("kgdb",	db_kgdb_cmd,	0,	NULL,NULL,NULL) },
332 #endif
333 	{ DDB_ADD_CMD("machine",NULL,CS_MACH,
334 	    "Architecture specific functions.",NULL,NULL) },
335 	{ DDB_ADD_CMD("match",	db_trace_until_matching_cmd,0,
336 	    "Stop at the matching return instruction.","See help next",NULL) },
337 	{ DDB_ADD_CMD("next",	db_trace_until_matching_cmd,0,
338 	    "Stop at the matching return instruction.","[/p]",NULL) },
339 	{ DDB_ADD_CMD("p",		db_print_cmd,		0,
340 	    "Print address according to the format.",
341 	    "[/axzodurc] address [address ...]",NULL) },
342 	{ DDB_ADD_CMD("print",	db_print_cmd,		0,
343 	    "Print address according to the format.",
344 	    "[/axzodurc] address [address ...]",NULL) },
345 	{ DDB_ADD_CMD("ps",		db_show_all_procs,	0,
346 	    "Print all processes.","See show all procs",NULL) },
347 	{ DDB_ADD_CMD("quit",		db_continue_cmd,	0,
348 	    "Continue execution.", "[/c]",NULL) },
349 	{ DDB_ADD_CMD("reboot",	db_reboot_cmd,		CS_OWN,
350 	    "Reboot","0x1  RB_ASKNAME, 0x2 RB_SINGLE, 0x4 RB_NOSYNC, 0x8 RB_HALT,"
351 	    "0x40 RB_KDB, 0x100 RB_DUMP, 0x808 RB_POWERDOWN",NULL) },
352 	{ DDB_ADD_CMD("s",		db_single_step_cmd,	0,
353 	    "Single-step count times.","[/p] [,count]",NULL) },
354 	{ DDB_ADD_CMD("search",	db_search_cmd,		CS_OWN|CS_SET_DOT,
355 	    "Search memory from address for value.",
356 	    "[/bhl] address value [mask] [,count]",NULL) },
357 	{ DDB_ADD_CMD("set",	db_set_cmd,		CS_OWN,
358 	    "Set the named variable","$variable [=] expression",NULL) },
359 	{ DDB_ADD_CMD("show",	NULL, CS_SHOW,
360 	    "Show kernel stats.", NULL,NULL) },
361 	{ DDB_ADD_CMD("sifting",	db_sifting_cmd,		CS_OWN,
362 	    "Search the symbol tables ","[/F] string",NULL) },
363 	{ DDB_ADD_CMD("step",	db_single_step_cmd,	0,
364 	    "Single-step count times.","[/p] [,count]",NULL) },
365 	{ DDB_ADD_CMD("sync",	db_sync_cmd,		CS_OWN,
366 	    "Force a crash dump, and then reboot.",NULL,NULL) },
367 	{ DDB_ADD_CMD("trace",	db_stack_trace_cmd,	0,
368 	    "Stack trace from frame-address.",
369 	    "[/u[l]] [frame-address][,count]",NULL) },
370 	{ DDB_ADD_CMD("until",	db_trace_until_call_cmd,0,
371 	    "Stop at the next call or return instruction.","[/p]",NULL) },
372 	{ DDB_ADD_CMD("w",		db_write_cmd,		CS_MORE|CS_SET_DOT,
373 	    "Write the expressions at succeeding locations.",
374 	    "[/bhl] address expression [expression ...]",NULL) },
375 	{ DDB_ADD_CMD("watch",	db_watchpoint_cmd,	CS_MORE,
376 	    "Set a watchpoint for a region. ","address[,size]",NULL) },
377 	{ DDB_ADD_CMD("whatis",	db_whatis_cmd, 0,
378 	    "Describe what an address is", "address", NULL) },
379 	{ DDB_ADD_CMD("write",	db_write_cmd,		CS_MORE|CS_SET_DOT,
380 	    "Write the expressions at succeeding locations.",
381 	    "[/bhl] address expression [expression ...]",NULL) },
382 	{ DDB_ADD_CMD("x",		db_examine_cmd,		CS_SET_DOT,
383 	    "Display the address locations.",
384 	    "[/modifier] address[,count]",NULL) },
385 	{ DDB_ADD_CMD(NULL, 	NULL,		   0, NULL, NULL, NULL) }
386 };
387 
388 static const struct db_command	*db_last_command = NULL;
389 #if defined(DDB_COMMANDONENTER)
390 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = ___STRING(DDB_COMMANDONENTER);
391 #else /* defined(DDB_COMMANDONENTER) */
392 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = "";
393 #endif /* defined(DDB_COMMANDONENTER) */
394 #define	DB_LINE_SEP	';'
395 
396 /*
397  * Execute commandlist after ddb start
398  * This function goes through the command list created from commands and ';'
399  */
400 static void
401 db_execute_commandlist(const char *cmdlist)
402 {
403 	const char *cmd = cmdlist;
404 	const struct db_command	*dummy = NULL;
405 
406 	while (*cmd != '\0') {
407 		const char *ep = cmd;
408 
409 		while (*ep != '\0' && *ep != DB_LINE_SEP) {
410 			ep++;
411 		}
412 		db_set_line(cmd, ep);
413 		db_command(&dummy);
414 		cmd = ep;
415 		if (*cmd == DB_LINE_SEP) {
416 			cmd++;
417 		}
418 	}
419 }
420 
421 /* Initialize ddb command tables */
422 void
423 db_init_commands(void)
424 {
425 	static bool done = false;
426 
427 	if (done) return;
428 	done = true;
429 
430 	/* register command tables */
431 	(void)db_register_tbl_entry(DDB_BASE_CMD, &db_base_cmd_builtins);
432 #ifdef DB_MACHINE_COMMANDS
433 	(void)db_register_tbl_entry(DDB_MACH_CMD, &db_mach_cmd_builtins);
434 #endif
435 	(void)db_register_tbl_entry(DDB_SHOW_CMD, &db_show_cmd_builtins);
436 }
437 
438 
439 /*
440  * Add command table to the specified list
441  * Arg:
442  * int type specifies type of command table DDB_SHOW_CMD|DDB_BASE_CMD|DDB_MAC_CMD
443  * *cmd_tbl poiter to static allocated db_command table
444  *
445  * Command table must be NULL terminated array of struct db_command
446  */
447 int
448 db_register_tbl(uint8_t type, const struct db_command *cmd_tbl)
449 {
450 	struct db_cmd_tbl_en *list_ent;
451 
452 	/* empty list - ignore */
453 	if (cmd_tbl->name == 0)
454 		return 0;
455 
456 	/* force builtin commands to be registered first */
457 	db_init_commands();
458 
459 	/* now create a list entry for this table */
460 	list_ent = db_zalloc(sizeof(*list_ent));
461 	if (list_ent == NULL)
462 		return ENOMEM;
463 	list_ent->db_cmd=cmd_tbl;
464 
465 	/* and register it */
466 	return db_register_tbl_entry(type, list_ent);
467 }
468 
469 static int
470 db_register_tbl_entry(uint8_t type, struct db_cmd_tbl_en *list_ent)
471 {
472 	struct db_cmd_tbl_en_head *list;
473 
474 	switch(type) {
475 	case DDB_BASE_CMD:
476 		list = &db_base_cmd_list;
477 		break;
478 	case DDB_SHOW_CMD:
479 		list = &db_show_cmd_list;
480 		break;
481 	case DDB_MACH_CMD:
482 		list = &db_mach_cmd_list;
483 		break;
484 	default:
485 		return ENOENT;
486 	}
487 
488 	TAILQ_INSERT_TAIL(list, list_ent, db_cmd_next);
489 
490 	return 0;
491 }
492 
493 /*
494  * Remove command table specified with db_cmd address == cmd_tbl
495  */
496 int
497 db_unregister_tbl(uint8_t type,const struct db_command *cmd_tbl)
498 {
499 	struct db_cmd_tbl_en *list_ent;
500 	struct db_cmd_tbl_en_head *list;
501 
502 	/* find list on which the entry should live */
503 	switch (type) {
504 	case DDB_BASE_CMD:
505 		list=&db_base_cmd_list;
506 		break;
507 	case DDB_SHOW_CMD:
508 		list=&db_show_cmd_list;
509 		break;
510 	case DDB_MACH_CMD:
511 		list=&db_mach_cmd_list;
512 		break;
513 	default:
514 		return EINVAL;
515 	}
516 
517 	TAILQ_FOREACH (list_ent, list, db_cmd_next) {
518 		if (list_ent->db_cmd == cmd_tbl){
519 			TAILQ_REMOVE(list,
520 			    list_ent, db_cmd_next);
521 			db_free(list_ent, sizeof(*list_ent));
522 			return 0;
523 		}
524 	}
525 	return ENOENT;
526 }
527 
528 /* This function is called from machine trap code. */
529 void
530 db_command_loop(void)
531 {
532 	label_t	db_jmpbuf;
533 	label_t	*savejmp;
534 
535 	/*
536 	 * Initialize 'prev' and 'next' to dot.
537 	 */
538 	db_prev = db_dot;
539 	db_next = db_dot;
540 
541 	db_cmd_loop_done = false;
542 
543 	/* Init default command tables add machine, base,
544 	   show command tables to the list */
545 	db_init_commands();
546 
547 	/* save context for return from ddb */
548 	savejmp = db_recover;
549 	db_recover = &db_jmpbuf;
550 	(void) setjmp(&db_jmpbuf);
551 
552 	/* Execute default ddb start commands */
553 	db_execute_commandlist(db_cmd_on_enter);
554 
555 	(void) setjmp(&db_jmpbuf);
556 	while (!db_cmd_loop_done) {
557 		if (db_print_position() != 0)
558 			db_printf("\n");
559 		db_output_line = 0;
560 		(void) db_read_line();
561 		db_command(&db_last_command);
562 	}
563 
564 	db_recover = savejmp;
565 }
566 
567 /*
568  * Search command table for command prefix
569  */
570 static int
571 db_cmd_search_table(const char *name,
572 		    const struct db_command *table,
573 		    const struct db_command **cmdp)
574 {
575 
576 	const struct db_command	*cmd;
577 	int result;
578 
579 	result = CMD_NONE;
580 	*cmdp = NULL;
581 
582 	for (cmd = table; cmd->name != 0; cmd++) {
583 		const char *lp;
584 		const char *rp;
585 
586 		lp = name;
587 		rp = cmd->name;
588 		while (*lp != '\0' && *lp == *rp) {
589 			rp++;
590 			lp++;
591 		}
592 
593 		if (*lp != '\0') /* mismatch or extra chars in name */
594 			continue;
595 
596 		if (*rp == '\0') { /* exact match */
597 			*cmdp = cmd;
598 			return (CMD_EXACT);
599 		}
600 
601 		/* prefix match: end of name, not end of command */
602 		if (result == CMD_NONE) {
603 			result = CMD_PREFIX;
604 			*cmdp = cmd;
605 		}
606 		else if (result == CMD_PREFIX) {
607 			result = CMD_AMBIGUOUS;
608 			*cmdp = NULL;
609 		}
610 	}
611 
612 	return (result);
613 }
614 
615 
616 /*
617  * Search list of command tables for command
618  */
619 static int
620 db_cmd_search(const char *name,
621 	      struct db_cmd_tbl_en_head *list_head,
622 	      const struct db_command **cmdp)
623 {
624 	struct db_cmd_tbl_en *list_ent;
625 	const struct db_command *found_command;
626 	bool accept_prefix_match;
627 	int result;
628 
629 	result = CMD_NONE;
630 	found_command = NULL;
631 	accept_prefix_match = true;
632 
633 	TAILQ_FOREACH(list_ent, list_head, db_cmd_next) {
634 		const struct db_command *cmd;
635 		int found;
636 
637 		found = db_cmd_search_table(name, list_ent->db_cmd, &cmd);
638 		if (found == CMD_EXACT) {
639 			result = CMD_EXACT;
640 			found_command = cmd;
641 			break;
642 		}
643 
644 		if (found == CMD_PREFIX) {
645 			if (accept_prefix_match) {
646 				/*
647 				 * Continue search, but note current result
648 				 * in case we won't find anything else.
649 				 */
650 				accept_prefix_match = false;
651 				result = CMD_PREFIX;
652 				found_command = cmd;
653 			} else {
654 				/*
655 				 * Watch out for globally ambiguous
656 				 * prefix match that is not locally
657 				 * ambiguous - with one match in one
658 				 * table and another match(es) in
659 				 * another table.
660 				 */
661 				result = CMD_AMBIGUOUS;
662 				found_command = NULL;
663 			}
664 		}
665 		else if (found == CMD_AMBIGUOUS) {
666 			accept_prefix_match = false;
667 			result = CMD_AMBIGUOUS;
668 			found_command = NULL;
669 		}
670 	}
671 
672 	*cmdp = found_command;
673 	return result;
674 }
675 
676 static void
677 db_cmd_search_failed(char *name, int search_result)
678 {
679 	if (search_result == CMD_NONE)
680 		db_printf("No such command: %s\n", name);
681 	else
682 		db_printf("Ambiguous command: %s\n", name);
683 }
684 
685 
686 /*
687  * List commands to the console.
688  */
689 static void
690 db_cmd_list(const struct db_cmd_tbl_en_head *list)
691 {
692 
693 	struct db_cmd_tbl_en *list_ent;
694 	const struct db_command *table;
695 	size_t		i, j, w, columns, lines, numcmds, width=0;
696 	const char	*p;
697 
698 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
699 		table = list_ent->db_cmd;
700 		for (i = 0; table[i].name != NULL; i++) {
701 			w = strlen(table[i].name);
702 			if (w > width)
703 				width = w;
704 		}
705 	}
706 
707 	width = DB_NEXT_TAB(width);
708 
709 	columns = db_max_width / width;
710 	if (columns == 0)
711 		columns = 1;
712 
713 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
714 		table = list_ent->db_cmd;
715 
716 		for (numcmds = 0; table[numcmds].name != NULL; numcmds++)
717 			;
718 		lines = (numcmds + columns - 1) / columns;
719 
720 		for (i = 0; i < lines; i++) {
721 			for (j = 0; j < columns; j++) {
722 				p = table[j * lines + i].name;
723 				if (p)
724 					db_printf("%s", p);
725 				if (j * lines + i + lines >= numcmds) {
726 					db_putchar('\n');
727 					break;
728 				}
729 				if (p) {
730 					w = strlen(p);
731 					while (w < width) {
732 						w = DB_NEXT_TAB(w);
733 						db_putchar('\t');
734 					}
735 				}
736 			}
737 		}
738 	}
739 	return;
740 }
741 
742 /*
743  * Read complete command with all subcommands, starting with current
744  * db_tok_string. If subcommand is missing, print the list of all
745  * subcommands.  If command/subcommand is not found, print an error
746  * message.  Returns pointer to "leaf" command or NULL.
747  */
748 static const struct db_command *
749 db_read_command(void)
750 {
751 	const struct db_command *command;
752 	struct db_cmd_tbl_en_head *list;
753 	int found;
754 	int t;
755 
756 	list = &db_base_cmd_list;
757 	do {
758 		found = db_cmd_search(db_tok_string, list, &command);
759 		if (command == NULL) {
760 			db_cmd_search_failed(db_tok_string, found);
761 			db_flush_lex();
762 			return NULL;
763 		}
764 
765 		if (command->flag == CS_SHOW)
766 			list = &db_show_cmd_list;
767 		else if (command->flag == CS_MACH)
768 			list = &db_mach_cmd_list;
769 		else if (command->flag == CS_COMPAT)
770 			/* same list */;
771 		else
772 			break; /* expect no more subcommands */
773 
774 		t = db_read_token(); /* read subcommand */
775 		if (t != tIDENT) {
776 			/* if none given - just print all of them */
777 			db_cmd_list(list);
778 			db_flush_lex();
779 			return NULL;
780 		}
781 	} while (list != NULL);
782 
783 	return command;
784 }
785 
786 /*
787  * Parse command line and execute apropriate function.
788  */
789 static void
790 db_command(const struct db_command **last_cmdp)
791 {
792 	const struct db_command *command;
793 	static db_expr_t last_count = 0;
794 	db_expr_t	addr, count;
795 	char		modif[TOK_STRING_SIZE];
796 
797 	int			t;
798 	bool		have_addr = false;
799 
800 	command = NULL;
801 
802 	t = db_read_token();
803 	if ((t == tEOL) || (t == tCOMMA)) {
804 		/*
805 		 * An empty line repeats last command, at 'next'.
806 		 * Only a count repeats the last command with the new count.
807 		 */
808 		command = *last_cmdp;
809 
810 		if (!command)
811 			return;
812 
813 		addr = (db_expr_t)db_next;
814 		if (t == tCOMMA) {
815 			if (!db_expression(&count)) {
816 				db_printf("Count missing\n");
817 				db_flush_lex();
818 				return;
819 			}
820 		} else
821 			count = last_count;
822 		have_addr = false;
823 		modif[0] = '\0';
824 		db_skip_to_eol();
825 
826 	} else if (t == tEXCL) {
827 		db_fncall(0, 0, 0, NULL);
828 		return;
829 
830 	} else if (t != tIDENT) {
831 		db_printf("?\n");
832 		db_flush_lex();
833 		return;
834 
835 	} else {
836 
837 		command = db_read_command();
838 		if (command == NULL)
839 			return;
840 
841 		if ((command->flag & CS_OWN) == 0) {
842 
843 			/*
844 			 * Standard syntax:
845 			 * command [/modifier] [addr] [,count]
846 			 */
847 			t = db_read_token(); /* get modifier */
848 			if (t == tSLASH) {
849 				t = db_read_token();
850 				if (t != tIDENT) {
851 					db_printf("Bad modifier\n");
852 					db_flush_lex();
853 					return;
854 				}
855 				/* save modifier */
856 				strlcpy(modif, db_tok_string, sizeof(modif));
857 
858 			} else {
859 				db_unread_token(t);
860 				modif[0] = '\0';
861 			}
862 
863 			if (db_expression(&addr)) { /*get address*/
864 				db_dot = (db_addr_t) addr;
865 				db_last_addr = db_dot;
866 				have_addr = true;
867 			} else {
868 				addr = (db_expr_t) db_dot;
869 				have_addr = false;
870 			}
871 
872 			t = db_read_token();
873 			if (t == tCOMMA) { /*Get count*/
874 				if (!db_expression(&count)) {
875 					db_printf("Count missing\n");
876 					db_flush_lex();
877 					return;
878 				}
879 			} else {
880 				db_unread_token(t);
881 				count = -1;
882 			}
883 			if ((command->flag & CS_MORE) == 0) {
884 				db_skip_to_eol();
885 			}
886 		}
887 	}
888 
889 	if (command != NULL && command->flag & CS_NOREPEAT) {
890 		*last_cmdp = NULL;
891 		last_count = 0;
892 	} else {
893 		*last_cmdp = command;
894 		last_count = count;
895 	}
896 
897 
898 	if (command != NULL) {
899 		/*
900 		 * Execute the command.
901 		 */
902 		if (command->fcn != NULL)
903 			(*command->fcn)(addr, have_addr, count, modif);
904 
905 		if (command->flag & CS_SET_DOT) {
906 			/*
907 			 * If command changes dot, set dot to
908 			 * previous address displayed (if 'ed' style).
909 			 */
910 			if (db_ed_style)
911 				db_dot = db_prev;
912 			else
913 				db_dot = db_next;
914 		} else {
915 			/*
916 			 * If command does not change dot,
917 			 * set 'next' location to be the same.
918 			 */
919 			db_next = db_dot;
920 		}
921 	}
922 }
923 
924 /*
925  * Print help for commands
926  */
927 static void
928 db_help_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
929 const char *modif)
930 {
931 	const struct db_command *command;
932 	int t;
933 
934 	t = db_read_token();
935 
936 	/* is there another command after the "help"? */
937 	if (t != tIDENT) {
938 		/* print base commands */
939 		db_cmd_list(&db_base_cmd_list);
940 		return;
941 	}
942 
943 	command = db_read_command();
944 	if (command == NULL)
945 		return;
946 
947 #ifdef DDB_VERBOSE_HELP
948 	db_printf("Command: %s\n", command->name);
949 	if (command->cmd_descr != NULL)
950 		db_printf(" Description: %s\n", command->cmd_descr);
951 	if (command->cmd_arg != NULL)
952 		db_printf(" Arguments: %s\n", command->cmd_arg);
953 	if (command->cmd_arg_help != NULL)
954 		db_printf(" Arguments description:\n%s\n",
955 			  command->cmd_arg_help);
956 	if ((command->cmd_arg == NULL) && (command->cmd_descr == NULL))
957 		db_printf(" No help message.\n");
958 #endif
959 
960 	db_skip_to_eol();
961 }
962 
963 /*ARGSUSED*/
964 static void
965 db_map_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
966     const char *modif)
967 {
968 #ifdef _KERNEL
969 	bool full = false;
970 
971 	if (modif[0] == 'f')
972 		full = true;
973 
974 	if (have_addr == false)
975 		addr = (db_expr_t)(uintptr_t)db_read_ptr("kernel_map");
976 
977 	uvm_map_printit((struct vm_map *)(uintptr_t) addr, full, db_printf);
978 #endif	/* XXX CRASH(8) */
979 }
980 
981 /*ARGSUSED*/
982 static void
983 db_object_print_cmd(db_expr_t addr, bool have_addr,
984     db_expr_t count, const char *modif)
985 {
986 #ifdef _KERNEL /* XXX CRASH(8) */
987 	bool full = false;
988 
989 	if (modif[0] == 'f')
990 		full = true;
991 
992 	uvm_object_printit((struct uvm_object *)(uintptr_t) addr, full,
993 	    db_printf);
994 #endif
995 }
996 
997 /*ARGSUSED*/
998 static void
999 db_page_print_cmd(db_expr_t addr, bool have_addr,
1000     db_expr_t count, const char *modif)
1001 {
1002 #ifdef _KERNEL /* XXX CRASH(8) */
1003 	bool full = false;
1004 
1005 	if (modif[0] == 'f')
1006 		full = true;
1007 
1008 	uvm_page_printit((struct vm_page *)(uintptr_t) addr, full, db_printf);
1009 #endif
1010 }
1011 
1012 /*ARGSUSED*/
1013 static void
1014 db_show_all_pages(db_expr_t addr, bool have_addr,
1015     db_expr_t count, const char *modif)
1016 {
1017 
1018 #ifdef _KERNEL /* XXX CRASH(8) */
1019 	uvm_page_printall(db_printf);
1020 #endif
1021 }
1022 
1023 /*ARGSUSED*/
1024 static void
1025 db_buf_print_cmd(db_expr_t addr, bool have_addr,
1026     db_expr_t count, const char *modif)
1027 {
1028 #ifdef _KERNEL /* XXX CRASH(8) */
1029 	bool full = false;
1030 
1031 	if (modif[0] == 'f')
1032 		full = true;
1033 
1034 	vfs_buf_print((struct buf *)(uintptr_t) addr, full, db_printf);
1035 #endif
1036 }
1037 
1038 /*ARGSUSED*/
1039 static void
1040 db_event_print_cmd(db_expr_t addr, bool have_addr,
1041     db_expr_t count, const char *modif)
1042 {
1043 	bool showzero = false;
1044 	bool showall = true;
1045 	bool showintr = false;
1046 	bool showtrap = false;
1047 	bool showmisc = false;
1048 	struct evcnt ev, *evp;
1049 	char buf[80];
1050 	int i;
1051 
1052 	i = 0;
1053 	while (modif[i]) {
1054 		switch (modif[i]) {
1055 		case 'f':
1056 			showzero = true;
1057 			break;
1058 		case 'i':
1059 			showintr = true;
1060 			showall = false;
1061 			break;
1062 		case 't':
1063 			showtrap = true;
1064 			showall = false;
1065 			break;
1066 		case 'm':
1067 			showmisc = true;
1068 			showall = false;
1069 			break;
1070 		}
1071 		i++;
1072 	}
1073 
1074 	if (showall)
1075 		showmisc = showintr = showtrap = true;
1076 
1077 	evp = (struct evcnt *)db_read_ptr("allevents");
1078 	while (evp != NULL) {
1079 		db_read_bytes((db_addr_t)evp, sizeof(ev), (char *)&ev);
1080 		evp = ev.ev_list.tqe_next;
1081 		if (ev.ev_count == 0 && !showzero)
1082 			continue;
1083 		if (ev.ev_type == EVCNT_TYPE_INTR && !showintr)
1084 			continue;
1085 		if (ev.ev_type == EVCNT_TYPE_TRAP && !showtrap)
1086 			continue;
1087 		if (ev.ev_type == EVCNT_TYPE_MISC && !showmisc)
1088 			continue;
1089 		db_read_bytes((db_addr_t)ev.ev_group, ev.ev_grouplen + 1, buf);
1090 		db_printf("evcnt type %d: %s ", ev.ev_type, buf);
1091 		db_read_bytes((db_addr_t)ev.ev_name, ev.ev_namelen + 1, buf);
1092 		db_printf("%s = %lld\n", buf, (long long)ev.ev_count);
1093 	}
1094 }
1095 
1096 /*ARGSUSED*/
1097 static void
1098 db_vnode_print_cmd(db_expr_t addr, bool have_addr,
1099     db_expr_t count, const char *modif)
1100 {
1101 #ifdef _KERNEL /* XXX CRASH(8) */
1102 	bool full = false;
1103 
1104 	if (modif[0] == 'f')
1105 		full = true;
1106 
1107 	vfs_vnode_print((struct vnode *)(uintptr_t) addr, full, db_printf);
1108 #endif
1109 }
1110 
1111 /*ARGSUSED*/
1112 static void
1113 db_vmem_print_cmd(db_expr_t addr, bool have_addr,
1114     db_expr_t count, const char *modif)
1115 {
1116 
1117 #ifdef _KERNEL /* XXX CRASH(8) */
1118 	vmem_print((uintptr_t) addr, modif, db_printf);
1119 #endif
1120 }
1121 
1122 static void
1123 db_mount_print_cmd(db_expr_t addr, bool have_addr,
1124     db_expr_t count, const char *modif)
1125 {
1126 #ifdef _KERNEL	/* XXX CRASH(8) */
1127 	bool full = false;
1128 
1129 	if (modif[0] == 'f')
1130 		full = true;
1131 
1132 	vfs_mount_print((struct mount *)(uintptr_t) addr, full, db_printf);
1133 #endif
1134 }
1135 
1136 /*ARGSUSED*/
1137 static void
1138 db_mbuf_print_cmd(db_expr_t addr, bool have_addr,
1139     db_expr_t count, const char *modif)
1140 {
1141 
1142 #ifdef _KERNEL /* XXX CRASH(8) */
1143 	m_print((const struct mbuf *)(uintptr_t) addr, modif, db_printf);
1144 #endif
1145 }
1146 
1147 /*ARGSUSED*/
1148 static void
1149 db_pool_print_cmd(db_expr_t addr, bool have_addr,
1150     db_expr_t count, const char *modif)
1151 {
1152 
1153 #ifdef _KERNEL /* XXX CRASH(8) */
1154 	pool_printit((struct pool *)(uintptr_t) addr, modif, db_printf);
1155 #endif
1156 }
1157 
1158 /*ARGSUSED*/
1159 static void
1160 db_namecache_print_cmd(db_expr_t addr, bool have_addr,
1161     db_expr_t count, const char *modif)
1162 {
1163 
1164 #ifdef _KERNEL /* XXX CRASH(8) */
1165 	namecache_print((struct vnode *)(uintptr_t) addr, db_printf);
1166 #endif
1167 }
1168 
1169 /*ARGSUSED*/
1170 static void
1171 db_uvmexp_print_cmd(db_expr_t addr, bool have_addr,
1172     db_expr_t count, const char *modif)
1173 {
1174 
1175 #ifdef _KERNEL	/* XXX CRASH(8) */
1176 	uvmexp_print(db_printf);
1177 #endif
1178 }
1179 
1180 #ifdef KERNHIST
1181 /*ARGSUSED*/
1182 static void
1183 db_kernhist_print_cmd(db_expr_t addr, bool have_addr,
1184     db_expr_t count, const char *modif)
1185 {
1186 
1187 	kernhist_print(db_printf);
1188 }
1189 #endif
1190 
1191 /*ARGSUSED*/
1192 static void
1193 db_lock_print_cmd(db_expr_t addr, bool have_addr,
1194     db_expr_t count, const char *modif)
1195 {
1196 
1197 #ifdef _KERNEL	/* XXX CRASH(8) */
1198 	lockdebug_lock_print((void *)(uintptr_t)addr, db_printf);
1199 #endif
1200 }
1201 
1202 /*
1203  * Call random function:
1204  * !expr(arg,arg,arg)
1205  */
1206 /*ARGSUSED*/
1207 static void
1208 db_fncall(db_expr_t addr, bool have_addr,
1209     db_expr_t count, const char *modif)
1210 {
1211 #ifdef _KERNEL
1212 	db_expr_t	fn_addr;
1213 #define	MAXARGS		11
1214 	db_expr_t	args[MAXARGS];
1215 	int		nargs = 0;
1216 	db_expr_t	retval;
1217 	db_expr_t	(*func)(db_expr_t, ...);
1218 	int		t;
1219 
1220 	if (!db_expression(&fn_addr)) {
1221 		db_printf("Bad function\n");
1222 		db_flush_lex();
1223 		return;
1224 	}
1225 	func = (db_expr_t (*)(db_expr_t, ...))(uintptr_t) fn_addr;
1226 
1227 	t = db_read_token();
1228 	if (t == tLPAREN) {
1229 		if (db_expression(&args[0])) {
1230 			nargs++;
1231 			while ((t = db_read_token()) == tCOMMA) {
1232 				if (nargs == MAXARGS) {
1233 					db_printf("Too many arguments\n");
1234 					db_flush_lex();
1235 					return;
1236 				}
1237 				if (!db_expression(&args[nargs])) {
1238 					db_printf("Argument missing\n");
1239 					db_flush_lex();
1240 					return;
1241 				}
1242 				nargs++;
1243 			}
1244 			db_unread_token(t);
1245 		}
1246 		if (db_read_token() != tRPAREN) {
1247 			db_printf("?\n");
1248 			db_flush_lex();
1249 			return;
1250 		}
1251 	}
1252 	db_skip_to_eol();
1253 
1254 	while (nargs < MAXARGS) {
1255 		args[nargs++] = 0;
1256 	}
1257 
1258 	retval = (*func)(args[0], args[1], args[2], args[3], args[4],
1259 			 args[5], args[6], args[7], args[8], args[9]);
1260 	db_printf("%s\n", db_num_to_str(retval));
1261 #else	/* _KERNEL */
1262 	db_printf("This command can only be used in-kernel.\n");
1263 #endif	/* _KERNEL */
1264 }
1265 
1266 static void
1267 db_reboot_cmd(db_expr_t addr, bool have_addr,
1268     db_expr_t count, const char *modif)
1269 {
1270 #ifdef _KERNEL
1271 	db_expr_t bootflags;
1272 
1273 	/* Flags, default to RB_AUTOBOOT */
1274 	if (!db_expression(&bootflags))
1275 		bootflags = (db_expr_t)RB_AUTOBOOT;
1276 	if (db_read_token() != tEOL) {
1277 		db_error("?\n");
1278 		/*NOTREACHED*/
1279 	}
1280 	/*
1281 	 * We are leaving DDB, never to return upward.
1282 	 * Clear db_recover so that we can debug faults in functions
1283 	 * called from cpu_reboot.
1284 	 */
1285 	db_recover = 0;
1286 	panicstr = "reboot forced via kernel debugger";
1287 	cpu_reboot((int)bootflags, NULL);
1288 #else	/* _KERNEL */
1289 	db_printf("This command can only be used in-kernel.\n");
1290 #endif	/* _KERNEL */
1291 }
1292 
1293 static void
1294 db_sifting_cmd(db_expr_t addr, bool have_addr,
1295     db_expr_t count, const char *modif)
1296 {
1297 	int	mode, t;
1298 
1299 	t = db_read_token();
1300 	if (t == tSLASH) {
1301 		t = db_read_token();
1302 		if (t != tIDENT) {
1303 			bad_modifier:
1304 			db_printf("Bad modifier\n");
1305 			db_flush_lex();
1306 			return;
1307 		}
1308 		if (!strcmp(db_tok_string, "F"))
1309 			mode = 'F';
1310 		else
1311 			goto bad_modifier;
1312 		t = db_read_token();
1313 	} else
1314 		mode = 0;
1315 
1316 	if (t == tIDENT)
1317 		db_sifting(db_tok_string, mode);
1318 	else {
1319 		db_printf("Bad argument (non-string)\n");
1320 		db_flush_lex();
1321 	}
1322 }
1323 
1324 static void
1325 db_stack_trace_cmd(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
1326 {
1327 	register const char *cp = modif;
1328 	register char c;
1329 	void (*pr)(const char *, ...);
1330 
1331 	pr = db_printf;
1332 	while ((c = *cp++) != 0)
1333 		if (c == 'l')
1334 			pr = (void (*)(const char *, ...))printf;
1335 
1336 	if (count == -1)
1337 		count = 65535;
1338 
1339 	db_stack_trace_print(addr, have_addr, count, modif, pr);
1340 }
1341 
1342 static void
1343 db_sync_cmd(db_expr_t addr, bool have_addr,
1344     db_expr_t count, const char *modif)
1345 {
1346 #ifdef _KERNEL
1347 	/*
1348 	 * We are leaving DDB, never to return upward.
1349 	 * Clear db_recover so that we can debug faults in functions
1350 	 * called from cpu_reboot.
1351 	 */
1352 	db_recover = 0;
1353 	panicstr = "dump forced via kernel debugger";
1354 	cpu_reboot(RB_DUMP, NULL);
1355 #else	/* _KERNEL */
1356 	db_printf("This command can only be used in-kernel.\n");
1357 #endif	/* _KERNEL */
1358 }
1359 
1360 /*
1361  * Describe what an address is
1362  */
1363 void
1364 db_whatis_cmd(db_expr_t address, bool have_addr,
1365     db_expr_t count, const char *modif)
1366 {
1367 	const uintptr_t addr = (uintptr_t)address;
1368 
1369 	db_lwp_whatis(addr, db_printf);
1370 #ifdef _KERNEL	/* XXX CRASH(8) */
1371 	pool_whatis(addr, db_printf);
1372 	vmem_whatis(addr, db_printf);
1373 	uvm_whatis(addr, db_printf);
1374 	module_whatis(addr, db_printf);
1375 #endif
1376 }
1377