xref: /netbsd-src/sys/ddb/db_command.c (revision 0df165c04d0a9ca1adde9ed2b890344c937954a6)
1 /*	$NetBSD: db_command.c,v 1.111 2007/11/14 12:05:42 martin 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 1.111 2007/11/14 12:05:42 martin 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/malloc.h>
80 #include <sys/mbuf.h>
81 #include <sys/namei.h>
82 #include <sys/pool.h>
83 #include <sys/proc.h>
84 #include <sys/vnode.h>
85 #include <sys/lockdebug.h>
86 #include <sys/sleepq.h>
87 #include <sys/cpu.h>
88 
89 /*include queue macros*/
90 #include <sys/queue.h>
91 
92 #include <machine/db_machdep.h>		/* type definitions */
93 
94 #if defined(_KERNEL_OPT)
95 #include "opt_multiprocessor.h"
96 #endif
97 
98 #include <ddb/db_lex.h>
99 #include <ddb/db_output.h>
100 #include <ddb/db_command.h>
101 #include <ddb/db_break.h>
102 #include <ddb/db_watch.h>
103 #include <ddb/db_run.h>
104 #include <ddb/db_variables.h>
105 #include <ddb/db_interface.h>
106 #include <ddb/db_sym.h>
107 #include <ddb/db_extern.h>
108 
109 #include <uvm/uvm_extern.h>
110 #include <uvm/uvm_ddb.h>
111 
112 #include "arp.h"
113 
114 /*
115  * Results of command search.
116  */
117 #define	CMD_UNIQUE	0
118 #define	CMD_FOUND	1
119 #define	CMD_NONE	2
120 #define	CMD_AMBIGUOUS	3
121 
122 /*
123  * Exported global variables
124  */
125 bool		db_cmd_loop_done;
126 label_t		*db_recover;
127 db_addr_t	db_dot;
128 db_addr_t	db_last_addr;
129 db_addr_t	db_prev;
130 db_addr_t	db_next;
131 
132 
133 /*
134   New DDB api for adding and removing commands uses three lists, because
135   we use two types of commands
136   a) standard commands without subcommands -> reboot
137   b) show commands which are subcommands of show command -> show aio_jobs
138   c) if defined machine specific commands
139 
140   ddb_add_cmd, ddb_rem_cmd use type (DDB_SHOW_CMD||DDB_BASE_CMD)argument to
141   add them to representativ lists.
142 */
143 
144 static const struct db_command db_command_table[];
145 static const struct db_command db_show_cmds[];
146 #ifdef DB_MACHINE_COMMANDS
147 static const struct db_command db_machine_command_table[];
148 #endif
149 
150 /* the global queue of all command tables */
151 TAILQ_HEAD(db_cmd_tbl_en_head, db_cmd_tbl_en);
152 
153 /* TAILQ entry used to register command tables */
154 struct db_cmd_tbl_en {
155 	const struct db_command *db_cmd;	/* cmd table */
156 	TAILQ_ENTRY(db_cmd_tbl_en) db_cmd_next;
157 };
158 
159 /* head of base commands list */
160 static struct db_cmd_tbl_en_head db_base_cmd_list =
161 	TAILQ_HEAD_INITIALIZER(db_base_cmd_list);
162 static struct db_cmd_tbl_en db_base_cmd_builtins =
163      { .db_cmd = db_command_table };
164 
165 /* head of show commands list */
166 static struct db_cmd_tbl_en_head db_show_cmd_list =
167 	TAILQ_HEAD_INITIALIZER(db_show_cmd_list);
168 static struct db_cmd_tbl_en db_show_cmd_builtins =
169      { .db_cmd = db_show_cmds };
170 
171 /* head of machine commands list */
172 static struct db_cmd_tbl_en_head db_mach_cmd_list =
173 	TAILQ_HEAD_INITIALIZER(db_mach_cmd_list);
174 #ifdef DB_MACHINE_COMMANDS
175 static struct db_cmd_tbl_en db_mach_cmd_builtins =
176      { .db_cmd = db_machine_command_table };
177 #endif
178 
179 /*
180  * if 'ed' style: 'dot' is set at start of last item printed,
181  * and '+' points to next line.
182  * Otherwise: 'dot' points to next item, '..' points to last.
183  */
184 static bool	 db_ed_style = true;
185 
186 static void	db_init_commands(void);
187 static int	db_register_tbl_entry(uint8_t type,
188     struct db_cmd_tbl_en *list_ent);
189 static void	db_cmd_list(const struct db_cmd_tbl_en_head *);
190 static int	db_cmd_search(const char *, const struct db_command *,
191     const struct db_command **);
192 static void	db_command(const struct db_command **);
193 static void	db_buf_print_cmd(db_expr_t, bool, db_expr_t, const char *);
194 static void	db_event_print_cmd(db_expr_t, bool, db_expr_t, const char *);
195 static void	db_fncall(db_expr_t, bool, db_expr_t, const char *);
196 static int      db_get_list_type(const char *);
197 static void     db_help_print_cmd(db_expr_t, bool, db_expr_t, const char *);
198 static void	db_lock_print_cmd(db_expr_t, bool, db_expr_t, const char *);
199 static void	db_mount_print_cmd(db_expr_t, bool, db_expr_t, const char *);
200 static void	db_mbuf_print_cmd(db_expr_t, bool, db_expr_t, const char *);
201 static void	db_malloc_print_cmd(db_expr_t, bool, db_expr_t, const char *);
202 static void	db_map_print_cmd(db_expr_t, bool, db_expr_t, const char *);
203 static void	db_namecache_print_cmd(db_expr_t, bool, db_expr_t,
204 		    const char *);
205 static void	db_object_print_cmd(db_expr_t, bool, db_expr_t, const char *);
206 static void	db_page_print_cmd(db_expr_t, bool, db_expr_t, const char *);
207 static void	db_show_all_pages(db_expr_t, bool, db_expr_t, const char *);
208 static void	db_pool_print_cmd(db_expr_t, bool, db_expr_t, const char *);
209 static void	db_reboot_cmd(db_expr_t, bool, db_expr_t, const char *);
210 static void	db_sifting_cmd(db_expr_t, bool, db_expr_t, const char *);
211 static void	db_stack_trace_cmd(db_expr_t, bool, db_expr_t, const char *);
212 static void	db_sync_cmd(db_expr_t, bool, db_expr_t, const char *);
213 static void	db_uvmexp_print_cmd(db_expr_t, bool, db_expr_t, const char *);
214 static void	db_vnode_print_cmd(db_expr_t, bool, db_expr_t, const char *);
215 
216 static const struct db_command db_show_cmds[] = {
217 	/*added from all sub cmds*/
218 	{ DDB_ADD_CMD("callout",  db_show_callout,
219 	    0 ,"List all used callout functions.",NULL,NULL) },
220 	{ DDB_ADD_CMD("pages",	db_show_all_pages,
221 	    0 ,"List all used memory pages.",NULL,NULL) },
222 	{ DDB_ADD_CMD("procs",	db_show_all_procs,
223 	    0 ,"List all processes.",NULL,NULL) },
224 	{ DDB_ADD_CMD("pools",	db_show_all_pools,
225 	    0 ,"Show all poolS",NULL,NULL) },
226 	/*added from all sub cmds*/
227 	{ DDB_ADD_CMD("aio_jobs",	db_show_aio_jobs,	0,
228 	    "Show aio jobs",NULL,NULL) },
229 	{ DDB_ADD_CMD("all",	NULL,
230 	    CS_COMPAT, NULL,NULL,NULL) },
231 #if defined(INET) && (NARP > 0)
232 	{ DDB_ADD_CMD("arptab",	db_show_arptab,		0,NULL,NULL,NULL) },
233 #endif
234 	{ DDB_ADD_CMD("breaks",	db_listbreak_cmd, 	0,
235 	    "Display all breaks.",NULL,NULL) },
236 	{ DDB_ADD_CMD("buf",	db_buf_print_cmd,	0,
237 	    "Print the struct buf at address.", "[/f] address",NULL) },
238 	{ DDB_ADD_CMD("event",	db_event_print_cmd,	0,
239 	    "Print all the non-zero evcnt(9) event counters.", "[/f]",NULL) },
240 	{ DDB_ADD_CMD("lock",	db_lock_print_cmd,	0,NULL,NULL,NULL) },
241 	{ DDB_ADD_CMD("malloc",	db_malloc_print_cmd,0,NULL,NULL,NULL) },
242 	{ DDB_ADD_CMD("map",	db_map_print_cmd,	0,
243 	    "Print the vm_map at address.", "[/f] address",NULL) },
244 	{ DDB_ADD_CMD("mount",	db_mount_print_cmd,	0,
245 	    "Print the mount structure at address.", "[/f] address",NULL) },
246 	{ DDB_ADD_CMD("mbuf",	db_mbuf_print_cmd,	0,NULL,NULL,
247 	    "-c prints all mbuf chains") },
248 	{ DDB_ADD_CMD("ncache",	db_namecache_print_cmd,	0,
249 	    "Dump the namecache list.", "address",NULL) },
250 	{ DDB_ADD_CMD("object",	db_object_print_cmd,	0,
251 	    "Print the vm_object at address.", "[/f] address",NULL) },
252 	{ DDB_ADD_CMD("page",	db_page_print_cmd,	0,
253 	    "Print the vm_page at address.", "[/f] address",NULL) },
254 	{ DDB_ADD_CMD("pool",	db_pool_print_cmd,	0,
255 	    "Print the pool at address.", "[/clp] address",NULL) },
256 	{ DDB_ADD_CMD("registers",	db_show_regs,		0,
257 	    "Display the register set.", "[/u]",NULL) },
258 	{ DDB_ADD_CMD("sched_qs",	db_show_sched_qs,	0,
259 	    "Print the state of the scheduler's run queues.",
260 	    NULL,NULL) },
261 	{ DDB_ADD_CMD("uvmexp",	db_uvmexp_print_cmd, 0,
262 	    "Print a selection of UVM counters and statistics.",
263 	    NULL,NULL) },
264 	{ DDB_ADD_CMD("vnode",	db_vnode_print_cmd,	0,
265 	    "Print the vnode at address.", "[/f] address",NULL) },
266 	{ DDB_ADD_CMD("watches",	db_listwatch_cmd, 	0,
267 	    "Display all watchpoints.", NULL,NULL) },
268 	{ DDB_ADD_CMD(NULL,		NULL,			0,NULL,NULL,NULL) }
269 };
270 
271 /* arch/<arch>/<arch>/db_interface.c */
272 #ifdef DB_MACHINE_COMMANDS
273 extern const struct db_command db_machine_command_table[];
274 #endif
275 
276 static const struct db_command db_command_table[] = {
277 	{ DDB_ADD_CMD("b",		db_breakpoint_cmd,	0,
278 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
279 	{ DDB_ADD_CMD("break",	db_breakpoint_cmd,	0,
280 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
281 	{ DDB_ADD_CMD("bt",		db_stack_trace_cmd,	0,
282 	    "Show backtrace.", "See help trace.",NULL) },
283 	{ DDB_ADD_CMD("c",		db_continue_cmd,	0,
284 	    "Continue execution.", "[/c]",NULL) },
285 	{ DDB_ADD_CMD("call",	db_fncall,		CS_OWN,
286 	    "Call the function", "address[(expression[,...])]",NULL) },
287 	{ DDB_ADD_CMD("callout",	db_show_callout,	0, NULL,
288 	    NULL,NULL ) },
289 	{ DDB_ADD_CMD("continue",	db_continue_cmd,	0,
290 	    "Continue execution.", "[/c]",NULL) },
291 	{ DDB_ADD_CMD("d",		db_delete_cmd,		0,
292 	    "Delete a breakpoint.", "address | #number",NULL) },
293 	{ DDB_ADD_CMD("delete",	db_delete_cmd,		0,
294 	    "Delete a breakpoint.", "address | #number",NULL) },
295 	{ DDB_ADD_CMD("dmesg",	db_dmesg,		0,
296 	    "Show kernel message buffer.", "[count]",NULL) },
297 	{ DDB_ADD_CMD("dwatch",	db_deletewatch_cmd,	0,
298 	    "Delete the watchpoint.", "address",NULL) },
299 	{ DDB_ADD_CMD("examine",	db_examine_cmd,		CS_SET_DOT,
300 	    "Display the address locations.",
301 	    "[/modifier] address[,count]",NULL) },
302 	{ DDB_ADD_CMD("help",   db_help_print_cmd, CS_OWN|CS_NOREPEAT,
303 	    "Display help about commands",
304 	    "Use other commands as arguments.",NULL) },
305 	{ DDB_ADD_CMD("kill",	db_kill_proc,		CS_OWN,
306 	    "Send a signal to the process","pid[,signal_number]",
307 	    "   pid:\t\t\tthe process id (may need 0t prefix for decimal)\n"
308 	    "   signal_number:\tthe signal to send") },
309 #ifdef KGDB
310 	{ DDB_ADD_CMD("kgdb",	db_kgdb_cmd,	0,	NULL,NULL,NULL) },
311 #endif
312 	{ DDB_ADD_CMD("machine",NULL,CS_MACH,
313 	    "Architecture specific functions.",NULL,NULL) },
314 	{ DDB_ADD_CMD("match",	db_trace_until_matching_cmd,0,
315 	    "Stop at the matching return instruction.","See help next",NULL) },
316 	{ DDB_ADD_CMD("next",	db_trace_until_matching_cmd,0,
317 	    "Stop at the matching return instruction.","[/p]",NULL) },
318 	{ DDB_ADD_CMD("p",		db_print_cmd,		0,
319 	    "Print address according to the format.",
320 	    "[/axzodurc] address [address ...]",NULL) },
321 	{ DDB_ADD_CMD("print",	db_print_cmd,		0,
322 	    "Print address according to the format.",
323 	    "[/axzodurc] address [address ...]",NULL) },
324 	{ DDB_ADD_CMD("ps",		db_show_all_procs,	0,
325 	    "Print all processes.","See show all procs",NULL) },
326 	{ DDB_ADD_CMD("reboot",	db_reboot_cmd,		CS_OWN,
327 	    "Reboot","0x1  RB_ASKNAME, 0x2 RB_SINGLE, 0x4 RB_NOSYNC, 0x8 RB_HALT,"
328 	    "0x40 RB_KDB, 0x100 RB_DUMP, 0x808 RB_POWERDOWN",NULL) },
329 	{ DDB_ADD_CMD("s",		db_single_step_cmd,	0,
330 	    "Single-step count times.","[/p] [,count]",NULL) },
331 	{ DDB_ADD_CMD("search",	db_search_cmd,		CS_OWN|CS_SET_DOT,
332 	    "Search memory from address for value.",
333 	    "[/bhl] address value [mask] [,count]",NULL) },
334 	{ DDB_ADD_CMD("set",	db_set_cmd,		CS_OWN,
335 	    "Set the named variable","$variable [=] expression",NULL) },
336 	{ DDB_ADD_CMD("show",	NULL, CS_SHOW,
337 	    "Show kernel stats.", NULL,NULL) },
338 	{ DDB_ADD_CMD("sifting",	db_sifting_cmd,		CS_OWN,
339 	    "Search the symbol tables ","[/F] string",NULL) },
340 	{ DDB_ADD_CMD("step",	db_single_step_cmd,	0,
341 	    "Single-step count times.","[/p] [,count]",NULL) },
342 	{ DDB_ADD_CMD("sync",	db_sync_cmd,		CS_OWN,
343 	    "Force a crash dump, and then reboot.",NULL,NULL) },
344 	{ DDB_ADD_CMD("trace",	db_stack_trace_cmd,	0,
345 	    "Stack trace from frame-address.",
346 	    "[/u[l]] [frame-address][,count]",NULL) },
347 	{ DDB_ADD_CMD("until",	db_trace_until_call_cmd,0,
348 	    "Stop at the next call or return instruction.","[/p]",NULL) },
349 	{ DDB_ADD_CMD("w",		db_write_cmd,		CS_MORE|CS_SET_DOT,
350 	    "Set a watchpoint for a region. ","address[,size]",NULL) },
351 	{ DDB_ADD_CMD("watch",	db_watchpoint_cmd,	CS_MORE,
352 	    "Set a watchpoint for a region. ","address[,size]",NULL) },
353 	{ DDB_ADD_CMD("write",	db_write_cmd,		CS_MORE|CS_SET_DOT,
354 	    "Write the expressions at succeeding locations.",
355 	    "[/bhl] address expression [expression ...]",NULL) },
356 	{ DDB_ADD_CMD("x",		db_examine_cmd,		CS_SET_DOT,
357 	    "Display the address locations.",
358 	    "[/modifier] address[,count]",NULL) },
359 	{ DDB_ADD_CMD(NULL, 	NULL,		   0, NULL, NULL, NULL) }
360 };
361 
362 static const struct db_command	*db_last_command = NULL;
363 #if defined(DDB_COMMANDONENTER)
364 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = ___STRING(DDB_COMMANDONENTER);
365 #else /* defined(DDB_COMMANDONENTER) */
366 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = "";
367 #endif /* defined(DDB_COMMANDONENTER) */
368 #define	DB_LINE_SEP	';'
369 
370 /*
371  * Utility routine - discard tokens through end-of-line.
372  */
373 void
374 db_skip_to_eol(void)
375 {
376 	int t;
377 
378 	do {
379 		t = db_read_token();
380 	} while (t != tEOL);
381 }
382 
383 void
384 db_error(const char *s)
385 {
386 
387 	if (s)
388 		db_printf("%s", s);
389 	db_flush_lex();
390 	longjmp(db_recover);
391 }
392 
393 /*Execute commandlist after ddb start
394  *This function goes through the command list created from commands and ';'
395  */
396 
397 static void
398 db_execute_commandlist(const char *cmdlist)
399 {
400 	const char *cmd = cmdlist;
401 	const struct db_command	*dummy = NULL;
402 
403 	while (*cmd != '\0') {
404 		const char *ep = cmd;
405 
406 		while (*ep != '\0' && *ep != DB_LINE_SEP) {
407 			ep++;
408 		}
409 		db_set_line(cmd, ep);
410 		db_command(&dummy);
411 		cmd = ep;
412 		if (*cmd == DB_LINE_SEP) {
413 			cmd++;
414 		}
415 	}
416 }
417 
418 /*Initialize ddb command tables*/
419 void
420 db_init_commands(void)
421 {
422 	static bool done = false;
423 
424 	if (done) return;
425 	done = true;
426 
427 	/* register command tables */
428 	(void)db_register_tbl_entry(DDB_BASE_CMD, &db_base_cmd_builtins);
429 #ifdef DB_MACHINE_COMMANDS
430 	(void)db_register_tbl_entry(DDB_MACH_CMD, &db_mach_cmd_builtins);
431 #endif
432 	(void)db_register_tbl_entry(DDB_SHOW_CMD, &db_show_cmd_builtins);
433 }
434 
435 
436 /*
437  * Add command table to the specified list
438  * Arg:
439  * int type specifies type of command table DDB_SHOW_CMD|DDB_BASE_CMD|DDB_MAC_CMD
440  * *cmd_tbl poiter to static allocated db_command table
441  *
442  *Command table must be NULL terminated array of struct db_command
443  */
444 int
445 db_register_tbl(uint8_t type, const struct db_command *cmd_tbl)
446 {
447 	struct db_cmd_tbl_en *list_ent;
448 
449 	if (cmd_tbl->name == 0)
450 		/* empty list - ignore */
451 		return 0;
452 
453 	/* force builtin commands to be registered first */
454 	db_init_commands();
455 
456 	/* now create a list entry for this table */
457 	list_ent = malloc(sizeof(struct db_cmd_tbl_en), M_TEMP, M_ZERO);
458 	if (list_ent == NULL)
459 		return ENOMEM;
460 	list_ent->db_cmd=cmd_tbl;
461 
462 	/* and register it */
463 	return db_register_tbl_entry(type, list_ent);
464 }
465 
466 static int
467 db_register_tbl_entry(uint8_t type, struct db_cmd_tbl_en *list_ent)
468 {
469 	struct db_cmd_tbl_en_head *list;
470 
471 	switch(type) {
472 	case DDB_BASE_CMD:
473 		list = &db_base_cmd_list;
474 		break;
475 	case DDB_SHOW_CMD:
476 		list = &db_show_cmd_list;
477 		break;
478 	case DDB_MACH_CMD:
479 		list = &db_mach_cmd_list;
480 		break;
481 	default:
482 		return ENOENT;
483 	}
484 
485 	TAILQ_INSERT_TAIL(list, list_ent, db_cmd_next);
486 
487 	return 0;
488 }
489 
490 /*
491  * Remove command table specified with db_cmd address == cmd_tbl
492  */
493 int
494 db_unregister_tbl(uint8_t type,const struct db_command *cmd_tbl)
495 {
496 	struct db_cmd_tbl_en *list_ent;
497 	struct db_cmd_tbl_en_head *list;
498 
499 	/* find list on which the entry should live */
500 	switch (type) {
501 	case DDB_BASE_CMD:
502 		list=&db_base_cmd_list;
503 		break;
504 	case DDB_SHOW_CMD:
505 		list=&db_show_cmd_list;
506 		break;
507 	case DDB_MACH_CMD:
508 		list=&db_mach_cmd_list;
509 		break;
510 	default:
511 		return EINVAL;
512 	}
513 
514 	TAILQ_FOREACH (list_ent,list,db_cmd_next) {
515 		if (list_ent->db_cmd == cmd_tbl){
516 			TAILQ_REMOVE(list,
517 			    list_ent,db_cmd_next);
518 			free(list_ent,M_TEMP);
519 			return 0;
520 		}
521 	}
522 	return ENOENT;
523 }
524 
525 /*This function is called from machine trap code.*/
526 void
527 db_command_loop(void)
528 {
529 
530 	label_t	db_jmpbuf;
531 	label_t	*savejmp;
532 
533 	/*
534 	 * Initialize 'prev' and 'next' to dot.
535 	 */
536 	db_prev = db_dot;
537 	db_next = db_dot;
538 
539 	db_cmd_loop_done = false;
540 
541 	/*Init default command tables add machine, base,
542 	  show command tables to the list*/
543 	db_init_commands();
544 
545 	/*save context for return from ddb*/
546 	savejmp = db_recover;
547 	db_recover = &db_jmpbuf;
548 	(void) setjmp(&db_jmpbuf);
549 
550 	/*Execute default ddb start commands*/
551 	db_execute_commandlist(db_cmd_on_enter);
552 
553 	(void) setjmp(&db_jmpbuf);
554 	while (!db_cmd_loop_done) {
555 		if (db_print_position() != 0)
556 			db_printf("\n");
557 		db_output_line = 0;
558 
559 
560 #ifdef MULTIPROCESSOR
561 		db_printf("db{%ld}> ", (long)cpu_number());
562 #else
563 		db_printf("db> ");
564 #endif
565 		(void) db_read_line();
566 
567 		db_command(&db_last_command);
568 	}
569 
570 	db_recover = savejmp;
571 }
572 
573 /*
574  * Search for command table for command prefix
575  * ret: CMD_UNIQUE    -> completely matches command
576  *      CMD_FOUND     -> matches prefix of single command
577  *      CMD_AMBIGIOUS -> matches prefix of more than one command
578  *      CMD_NONE      -> command not found
579  */
580 static int
581 db_cmd_search(const char *name,const struct db_command *table,
582     const struct db_command **cmdp)
583 {
584 
585 	const struct db_command	*cmd;
586 	int result;
587 
588 	result = CMD_NONE;
589 	*cmdp = NULL;
590 	for (cmd = table; cmd->name != 0; cmd++) {
591 		const char *lp;
592 		const char *rp;
593 
594 		lp = name;
595 		rp = cmd->name;
596 		while (*lp != '\0' && *lp == *rp) {
597 			rp++;
598 			lp++;
599 		}
600 
601 		if (*lp != '\0') /* mismatch or extra chars in name */
602 			continue;
603 
604 		if (*rp == '\0') { /* complete match */
605 			*cmdp = cmd;
606 			return (CMD_UNIQUE);
607 		}
608 
609 		/* prefix match: end of name, not end of command */
610 		if (result == CMD_NONE) {
611 			result = CMD_FOUND;
612 			*cmdp = cmd;
613 		}
614 		else if (result == CMD_FOUND) {
615 			result = CMD_AMBIGUOUS;
616 			*cmdp = NULL;
617 		}
618 	}
619 
620 	return (result);
621 }
622 
623 /*
624  *List commands to the console.
625  */
626 static void
627 db_cmd_list(const struct db_cmd_tbl_en_head *list)
628 {
629 
630 	struct db_cmd_tbl_en *list_ent;
631 	const struct db_command *table;
632 	size_t		i, j, w, columns, lines, numcmds, width=0;
633 	const char	*p;
634 
635 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
636 		table = list_ent->db_cmd;
637 		for (i = 0; table[i].name != NULL; i++) {
638 			w = strlen(table[i].name);
639 			if (w > width)
640 				width = w;
641 		}
642 	}
643 
644 	width = DB_NEXT_TAB(width);
645 
646 	columns = db_max_width / width;
647 	if (columns == 0)
648 		columns = 1;
649 
650 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
651 		table = list_ent->db_cmd;
652 
653 		for (numcmds = 0; table[numcmds].name != NULL; numcmds++)
654 			;
655 		lines = (numcmds + columns - 1) / columns;
656 
657 		for (i = 0; i < lines; i++) {
658 			for (j = 0; j < columns; j++) {
659 				p = table[j * lines + i].name;
660 				if (p)
661 					db_printf("%s", p);
662 				if (j * lines + i + lines >= numcmds) {
663 					db_putchar('\n');
664 					break;
665 				}
666 				if (p) {
667 					w = strlen(p);
668 					while (w < width) {
669 						w = DB_NEXT_TAB(w);
670 						db_putchar('\t');
671 					}
672 				}
673 			}
674 		}
675 	}
676 	return;
677 }
678 
679 /*
680  *Returns type of list for command with name *name.
681  */
682 static int
683 db_get_list_type(const char *name)
684 {
685 
686 	const struct db_command    *cmd;
687 	struct db_cmd_tbl_en *list_ent;
688 	int error,ret=-1;
689 
690 	/* search for the command name */
691 	TAILQ_FOREACH(list_ent,&db_base_cmd_list,db_cmd_next) {
692 		/*
693 		 * cmd_search returns CMD_UNIQUE, CMD_FOUND ...
694 		 * CMD_UNIQUE when name was completly matched to cmd->name
695 		 * CMD_FOUND  when name was only partially matched to cmd->name
696 		 * CMD_NONE   command not found in a list
697 		 * CMD_AMBIGIOUS ->more partialy matches
698 		 */
699 
700 		error = db_cmd_search(name, list_ent->db_cmd, &cmd);
701 
702 		if (error == CMD_UNIQUE) {
703 			/* exact match found */
704 			if (cmd->flag == CS_SHOW) {
705 				ret = DDB_SHOW_CMD;
706 				break;
707 			}
708 			if (cmd->flag == CS_MACH) {
709 				ret = DDB_MACH_CMD;
710 				break;
711 			} else {
712 				ret = DDB_BASE_CMD;
713 				break;
714 			}
715 
716 		} else if (error == CMD_FOUND) {
717 			/*
718 			 * partial match, search will continue, but
719 			 * note current result in case we won't
720 			 * find anything better.
721 			 */
722 			if (cmd->flag == CS_SHOW)
723 				ret = DDB_SHOW_CMD;
724 			else if (cmd->flag == CS_MACH)
725 				ret = DDB_MACH_CMD;
726 			else
727 				ret = DDB_BASE_CMD;
728 		}
729 	}
730 
731 	return ret;
732 }
733 
734 /*
735  *Parse command line and execute apropriate function.
736  */
737 static void
738 db_command(const struct db_command **last_cmdp)
739 {
740 	const struct db_command *command;
741 	struct db_cmd_tbl_en *list_ent;
742 	struct db_cmd_tbl_en_head *list;
743 
744 	int		t;
745 	int		result;
746 
747 	char		modif[TOK_STRING_SIZE];
748 	db_expr_t	addr, count;
749 	bool		have_addr = false;
750 
751 	static db_expr_t last_count = 0;
752 
753 	command = NULL;	/* XXX gcc */
754 
755 	t = db_read_token();
756 	if ((t == tEOL) || (t == tCOMMA)) {
757 		/*
758 		 * An empty line repeats last command, at 'next'.
759 		 * Only a count repeats the last command with the new count.
760 		 */
761 		command = *last_cmdp;
762 
763 		if (!command)
764 			return;
765 
766 		addr = (db_expr_t)db_next;
767 		if (t == tCOMMA) {
768 			if (!db_expression(&count)) {
769 				db_printf("Count missing\n");
770 				db_flush_lex();
771 				return;
772 			}
773 		} else
774 			count = last_count;
775 		have_addr = false;
776 		modif[0] = '\0';
777 		db_skip_to_eol();
778 
779 	} else if (t == tEXCL) {
780 		db_fncall(0, 0, 0, NULL);
781 		return;
782 
783 	} else if (t != tIDENT) {
784 		db_printf("?\n");
785 		db_flush_lex();
786 		return;
787 
788 	} else {
789 
790 		switch(db_get_list_type(db_tok_string)) {
791 
792 		case DDB_BASE_CMD:
793 			list = &db_base_cmd_list;
794 			break;
795 
796 		case DDB_SHOW_CMD:
797 			list = &db_show_cmd_list;
798 			/* need to read show subcommand if show command list
799 			   is used. */
800 			t = db_read_token();
801 
802 			if (t != tIDENT) {
803 				/* if only show command is executed, print
804 				   all subcommands */
805 				db_cmd_list(list);
806 				db_flush_lex();
807 				return;
808 			}
809 			break;
810 		case DDB_MACH_CMD:
811 			list = &db_mach_cmd_list;
812 			/* need to read machine subcommand if
813 			  machine level 2 command list is used. */
814 			t = db_read_token();
815 
816 			if (t != tIDENT) {
817 				/* if only show command is executed, print
818 				   all subcommands */
819 				db_cmd_list(list);
820 				db_flush_lex();
821 				return;
822 			}
823 			break;
824 		default:
825 			db_printf("No such command\n");
826 			db_flush_lex();
827 			return;
828 		}
829 
830  COMPAT_RET:
831 		TAILQ_FOREACH(list_ent, list, db_cmd_next) {
832 			result = db_cmd_search(db_tok_string, list_ent->db_cmd,
833 			    &command);
834 
835 			/* after CMD_UNIQUE in cmd_list only a single command
836 			   name is possible */
837 			if (result == CMD_UNIQUE)
838 				break;
839 
840 		}
841 
842                 /* check compatibility flag */
843 		if (command && command->flag & CS_COMPAT){
844 			t = db_read_token();
845 			if (t != tIDENT) {
846 					db_cmd_list(list);
847 					db_flush_lex();
848 					return;
849 			}
850 
851 			/* support only level 2 commands here */
852 			goto COMPAT_RET;
853 		}
854 
855 		if (!command) {
856 			db_printf("No such command\n");
857 			db_flush_lex();
858 			return;
859 		}
860 
861 		if ((command->flag & CS_OWN) == 0) {
862 
863 			/*
864 			 * Standard syntax:
865 			 * command [/modifier] [addr] [,count]
866 			 */
867 			t = db_read_token(); /* get modifier */
868 			if (t == tSLASH) {
869 				t = db_read_token();
870 				if (t != tIDENT) {
871 					db_printf("Bad modifier\n");
872 					db_flush_lex();
873 					return;
874 				}
875 				/* save modifier */
876 				strlcpy(modif, db_tok_string, sizeof(modif));
877 
878 			} else {
879 				db_unread_token(t);
880 				modif[0] = '\0';
881 			}
882 
883 			if (db_expression(&addr)) { /*get address*/
884 				db_dot = (db_addr_t) addr;
885 				db_last_addr = db_dot;
886 				have_addr = true;
887 			} else {
888 				addr = (db_expr_t) db_dot;
889 				have_addr = false;
890 			}
891 
892 			t = db_read_token();
893 			if (t == tCOMMA) { /*Get count*/
894 				if (!db_expression(&count)) {
895 					db_printf("Count missing\n");
896 					db_flush_lex();
897 					return;
898 				}
899 			} else {
900 				db_unread_token(t);
901 				count = -1;
902 			}
903 			if ((command->flag & CS_MORE) == 0) {
904 				db_skip_to_eol();
905 			}
906 		}
907 	}
908 
909 	if (command->flag & CS_NOREPEAT) {
910 		*last_cmdp = NULL;
911 		last_count = 0;
912 	} else {
913 		*last_cmdp = command;
914 		last_count = count;
915 	}
916 
917 	if (command != NULL) {
918 		/*
919 		 * Execute the command.
920 		 */
921 		if (command->fcn != NULL)
922 			(*command->fcn)(addr, have_addr, count, modif);
923 
924 		if (command->flag & CS_SET_DOT) {
925 			/*
926 			 * If command changes dot, set dot to
927 			 * previous address displayed (if 'ed' style).
928 			 */
929 			if (db_ed_style)
930 				db_dot = db_prev;
931 			else
932 				db_dot = db_next;
933 		} else {
934 			/*
935 			 * If command does not change dot,
936 			 * set 'next' location to be the same.
937 			 */
938 			db_next = db_dot;
939 		}
940 	}
941 }
942 
943 /*
944  * Print help for commands
945  */
946 static void
947 db_help_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
948     const char *modif)
949 {
950 
951 	const struct db_cmd_tbl_en_head *list;
952 	const struct db_cmd_tbl_en *list_ent;
953 	const struct db_command *help = NULL;
954 	int t, result;
955 
956 	t = db_read_token();
957 	/* is there another command after the "help"? */
958 	if (t == tIDENT){
959 
960 		switch(db_get_list_type(db_tok_string)) {
961 
962 		case DDB_BASE_CMD:
963 			list=&db_base_cmd_list;
964 			break;
965 		case DDB_SHOW_CMD:
966 			list=&db_show_cmd_list;
967 			/* read the show subcommand */
968 			t = db_read_token();
969 
970 			if (t != tIDENT) {
971 				/* no subcommand, print the list */
972 				db_cmd_list(list);
973 				db_flush_lex();
974 				return;
975 			}
976 
977 			break;
978 		case DDB_MACH_CMD:
979 			list=&db_mach_cmd_list;
980 			/* read machine subcommand */
981 			t = db_read_token();
982 
983 			if (t != tIDENT) {
984 				/* no subcommand - just print the list */
985 				db_cmd_list(list);
986 				db_flush_lex();
987 				return;
988 			}
989 			break;
990 
991 		default:
992 			db_printf("No such command\n");
993 			db_flush_lex();
994 			return;
995 		}
996  COMPAT_RET:
997 		TAILQ_FOREACH(list_ent,list,db_cmd_next){
998 			result = db_cmd_search(db_tok_string, list_ent->db_cmd,
999 					&help);
1000 			/* after CMD_UNIQUE only a single command
1001 			   name is possible */
1002 			if (result == CMD_UNIQUE)
1003 				break;
1004 		}
1005 #ifdef DDB_VERBOSE_HELP
1006 		/*print help*/
1007 
1008 		db_printf("Command: %s\n",help->name);
1009 
1010 		if (help->cmd_descr != NULL)
1011 			db_printf(" Description: %s\n",help->cmd_descr);
1012 
1013 		if (help->cmd_arg != NULL)
1014 			db_printf(" Arguments: %s\n",help->cmd_arg);
1015 
1016 		if (help->cmd_arg_help != NULL)
1017 			db_printf(" Arguments description:\n%s\n",
1018 			    help->cmd_arg_help);
1019 
1020 		if ((help->cmd_arg == NULL) && (help->cmd_descr == NULL))
1021 			db_printf("%s Doesn't have any help message included.\n",
1022 			    help->name);
1023 #endif
1024 		/* check compatibility flag */
1025 		/*
1026 		 * The "show all" command table has been merged with the
1027 		 * "show" command table - but we want to keep the old UI
1028 		 * available. So if we find a CS_COMPAT entry, we read
1029 		 * the next token and try again.
1030 		 */
1031 		if (help->flag == CS_COMPAT){
1032 			t = db_read_token();
1033 
1034 			if (t != tIDENT){
1035 				db_cmd_list(list);
1036 				db_flush_lex();
1037 				return;
1038 			}
1039 
1040 			goto COMPAT_RET;
1041 			/* support only level 2 commands here */
1042 		} else {
1043 			db_skip_to_eol();
1044 		}
1045 
1046 	} else /* t != tIDENT */
1047 		/* print base commands */
1048 		db_cmd_list(&db_base_cmd_list);
1049 
1050 	return;
1051 }
1052 
1053 /*ARGSUSED*/
1054 static void
1055 db_map_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
1056     const char *modif)
1057 {
1058 	bool full = false;
1059 
1060 	if (modif[0] == 'f')
1061 		full = true;
1062 
1063 	if (have_addr == false)
1064 		addr = (db_expr_t)(intptr_t) kernel_map;
1065 
1066 	uvm_map_printit((struct vm_map *)(intptr_t) addr, full, db_printf);
1067 }
1068 
1069 /*ARGSUSED*/
1070 static void
1071 db_malloc_print_cmd(db_expr_t addr, bool have_addr,
1072     db_expr_t count, const char *modif)
1073 {
1074 
1075 #ifdef MALLOC_DEBUG
1076 	if (!have_addr)
1077 		addr = 0;
1078 
1079 	debug_malloc_printit(db_printf, (vaddr_t) addr);
1080 #else
1081 	db_printf("The kernel is not built with the MALLOC_DEBUG option.\n");
1082 #endif /* MALLOC_DEBUG */
1083 }
1084 
1085 /*ARGSUSED*/
1086 static void
1087 db_object_print_cmd(db_expr_t addr, bool have_addr,
1088     db_expr_t count, const char *modif)
1089 {
1090 	bool full = false;
1091 
1092 	if (modif[0] == 'f')
1093 		full = true;
1094 
1095 	uvm_object_printit((struct uvm_object *)(intptr_t) addr, full,
1096 	    db_printf);
1097 }
1098 
1099 /*ARGSUSED*/
1100 static void
1101 db_page_print_cmd(db_expr_t addr, bool have_addr,
1102     db_expr_t count, const char *modif)
1103 {
1104 	bool full = false;
1105 
1106 	if (modif[0] == 'f')
1107 		full = true;
1108 
1109 	uvm_page_printit((struct vm_page *)(intptr_t) addr, full, db_printf);
1110 }
1111 
1112 /*ARGSUSED*/
1113 static void
1114 db_show_all_pages(db_expr_t addr, bool have_addr,
1115     db_expr_t count, const char *modif)
1116 {
1117 
1118 	uvm_page_printall(db_printf);
1119 }
1120 
1121 /*ARGSUSED*/
1122 static void
1123 db_buf_print_cmd(db_expr_t addr, bool have_addr,
1124     db_expr_t count, const char *modif)
1125 {
1126 	bool full = false;
1127 
1128 	if (modif[0] == 'f')
1129 		full = true;
1130 
1131 	vfs_buf_print((struct buf *)(intptr_t) addr, full, db_printf);
1132 }
1133 
1134 /*ARGSUSED*/
1135 static void
1136 db_event_print_cmd(db_expr_t addr, bool have_addr,
1137     db_expr_t count, const char *modif)
1138 {
1139 	bool full = false;
1140 
1141 	if (modif[0] == 'f')
1142 		full = true;
1143 
1144 	event_print(full, db_printf);
1145 }
1146 
1147 /*ARGSUSED*/
1148 static void
1149 db_vnode_print_cmd(db_expr_t addr, bool have_addr,
1150     db_expr_t count, const char *modif)
1151 {
1152 	bool full = false;
1153 
1154 	if (modif[0] == 'f')
1155 		full = true;
1156 
1157 	vfs_vnode_print((struct vnode *)(intptr_t) addr, full, db_printf);
1158 }
1159 
1160 static void
1161 db_mount_print_cmd(db_expr_t addr, bool have_addr,
1162     db_expr_t count, const char *modif)
1163 {
1164 	bool full = false;
1165 
1166 	if (modif[0] == 'f')
1167 		full = true;
1168 
1169 	vfs_mount_print((struct mount *)(intptr_t) addr, full, db_printf);
1170 }
1171 
1172 /*ARGSUSED*/
1173 static void
1174 db_mbuf_print_cmd(db_expr_t addr, bool have_addr,
1175     db_expr_t count, const char *modif)
1176 {
1177 
1178 	m_print((const struct mbuf *)(intptr_t) addr, modif, db_printf);
1179 }
1180 
1181 /*ARGSUSED*/
1182 static void
1183 db_pool_print_cmd(db_expr_t addr, bool have_addr,
1184     db_expr_t count, const char *modif)
1185 {
1186 
1187 	pool_printit((struct pool *)(intptr_t) addr, modif, db_printf);
1188 }
1189 
1190 /*ARGSUSED*/
1191 static void
1192 db_namecache_print_cmd(db_expr_t addr, bool have_addr,
1193     db_expr_t count, const char *modif)
1194 {
1195 
1196 	namecache_print((struct vnode *)(intptr_t) addr, db_printf);
1197 }
1198 
1199 /*ARGSUSED*/
1200 static void
1201 db_uvmexp_print_cmd(db_expr_t addr, bool have_addr,
1202     db_expr_t count, const char *modif)
1203 {
1204 
1205 	uvmexp_print(db_printf);
1206 }
1207 
1208 /*ARGSUSED*/
1209 static void
1210 db_lock_print_cmd(db_expr_t addr, bool have_addr,
1211     db_expr_t count, const char *modif)
1212 {
1213 
1214 	lockdebug_lock_print((void *)addr, db_printf);
1215 }
1216 
1217 /*
1218  * Call random function:
1219  * !expr(arg,arg,arg)
1220  */
1221 /*ARGSUSED*/
1222 static void
1223 db_fncall(db_expr_t addr, bool have_addr,
1224     db_expr_t count, const char *modif)
1225 {
1226 	db_expr_t	fn_addr;
1227 #define	MAXARGS		11
1228 	db_expr_t	args[MAXARGS];
1229 	int		nargs = 0;
1230 	db_expr_t	retval;
1231 	db_expr_t	(*func)(db_expr_t, ...);
1232 	int		t;
1233 
1234 	if (!db_expression(&fn_addr)) {
1235 		db_printf("Bad function\n");
1236 		db_flush_lex();
1237 		return;
1238 	}
1239 	func = (db_expr_t (*)(db_expr_t, ...))(intptr_t) fn_addr;
1240 
1241 	t = db_read_token();
1242 	if (t == tLPAREN) {
1243 		if (db_expression(&args[0])) {
1244 			nargs++;
1245 			while ((t = db_read_token()) == tCOMMA) {
1246 				if (nargs == MAXARGS) {
1247 					db_printf("Too many arguments\n");
1248 					db_flush_lex();
1249 					return;
1250 				}
1251 				if (!db_expression(&args[nargs])) {
1252 					db_printf("Argument missing\n");
1253 					db_flush_lex();
1254 					return;
1255 				}
1256 				nargs++;
1257 			}
1258 			db_unread_token(t);
1259 		}
1260 		if (db_read_token() != tRPAREN) {
1261 			db_printf("?\n");
1262 			db_flush_lex();
1263 			return;
1264 		}
1265 	}
1266 	db_skip_to_eol();
1267 
1268 	while (nargs < MAXARGS) {
1269 		args[nargs++] = 0;
1270 	}
1271 
1272 	retval = (*func)(args[0], args[1], args[2], args[3], args[4],
1273 			 args[5], args[6], args[7], args[8], args[9]);
1274 	db_printf("%s\n", db_num_to_str(retval));
1275 }
1276 
1277 static void
1278 db_reboot_cmd(db_expr_t addr, bool have_addr,
1279     db_expr_t count, const char *modif)
1280 {
1281 	db_expr_t bootflags;
1282 
1283 	/* Flags, default to RB_AUTOBOOT */
1284 	if (!db_expression(&bootflags))
1285 		bootflags = (db_expr_t)RB_AUTOBOOT;
1286 	if (db_read_token() != tEOL) {
1287 		db_error("?\n");
1288 		/*NOTREACHED*/
1289 	}
1290 	/*
1291 	 * We are leaving DDB, never to return upward.
1292 	 * Clear db_recover so that we can debug faults in functions
1293 	 * called from cpu_reboot.
1294 	 */
1295 	db_recover = 0;
1296 	cpu_reboot((int)bootflags, NULL);
1297 }
1298 
1299 static void
1300 db_sifting_cmd(db_expr_t addr, bool have_addr,
1301     db_expr_t count, const char *modif)
1302 {
1303 	int	mode, t;
1304 
1305 	t = db_read_token();
1306 	if (t == tSLASH) {
1307 		t = db_read_token();
1308 		if (t != tIDENT) {
1309 			bad_modifier:
1310 			db_printf("Bad modifier\n");
1311 			db_flush_lex();
1312 			return;
1313 		}
1314 		if (!strcmp(db_tok_string, "F"))
1315 			mode = 'F';
1316 		else
1317 			goto bad_modifier;
1318 		t = db_read_token();
1319 	} else
1320 		mode = 0;
1321 
1322 	if (t == tIDENT)
1323 		db_sifting(db_tok_string, mode);
1324 	else {
1325 		db_printf("Bad argument (non-string)\n");
1326 		db_flush_lex();
1327 	}
1328 }
1329 
1330 static void
1331 db_stack_trace_cmd(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
1332 {
1333 	register const char *cp = modif;
1334 	register char c;
1335 	void (*pr)(const char *, ...);
1336 
1337 	pr = db_printf;
1338 	while ((c = *cp++) != 0)
1339 		if (c == 'l')
1340 			pr = printf;
1341 
1342 	if (count == -1)
1343 		count = 65535;
1344 
1345 	db_stack_trace_print(addr, have_addr, count, modif, pr);
1346 }
1347 
1348 static void
1349 db_sync_cmd(db_expr_t addr, bool have_addr,
1350     db_expr_t count, const char *modif)
1351 {
1352 
1353 	/*
1354 	 * We are leaving DDB, never to return upward.
1355 	 * Clear db_recover so that we can debug faults in functions
1356 	 * called from cpu_reboot.
1357 	 */
1358 	db_recover = 0;
1359 	cpu_reboot(RB_DUMP, NULL);
1360 }
1361