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db_command.c revision 1.142
      1 /*	$NetBSD: db_command.c,v 1.142 2013/01/06 04:17:27 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 (at) 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 1.142 2013/01/06 04:17:27 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 #ifdef _KERNEL	/* XXX CRASH(8) */
    216 	{ DDB_ADD_CMD("callout",  db_show_callout,
    217 	    0 ,"List all used callout functions.",NULL,NULL) },
    218 #endif
    219 	{ DDB_ADD_CMD("pages",	db_show_all_pages,
    220 	    0 ,"List all used memory pages.",NULL,NULL) },
    221 	{ DDB_ADD_CMD("proc",	db_show_proc,
    222 	    0 ,"Print process information.",NULL,NULL) },
    223 	{ DDB_ADD_CMD("procs",	db_show_all_procs,
    224 	    0 ,"List all processes.",NULL,NULL) },
    225 	{ DDB_ADD_CMD("pools",	db_show_all_pools,
    226 	    0 ,"Show all pools",NULL,NULL) },
    227 #ifdef AIO
    228 	/*added from all sub cmds*/
    229 	{ DDB_ADD_CMD("aio_jobs",	db_show_aio_jobs,	0,
    230 	    "Show aio jobs",NULL,NULL) },
    231 #endif
    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 #ifdef _KERNEL
    238 	{ DDB_ADD_CMD("breaks",	db_listbreak_cmd, 	0,
    239 	    "Display all breaks.",NULL,NULL) },
    240 #endif
    241 	{ DDB_ADD_CMD("buf",	db_buf_print_cmd,	0,
    242 	    "Print the struct buf at address.", "[/f] address",NULL) },
    243 	{ DDB_ADD_CMD("event",	db_event_print_cmd,	0,
    244 	    "Print all the non-zero evcnt(9) event counters.", "[/fitm]",NULL) },
    245 	{ DDB_ADD_CMD("files", db_show_files_cmd,	0,
    246 	    "Print the files open by process at address",
    247 	    "[/f] address", NULL) },
    248 	{ DDB_ADD_CMD("lock",	db_lock_print_cmd,	0,NULL,NULL,NULL) },
    249 	{ DDB_ADD_CMD("map",	db_map_print_cmd,	0,
    250 	    "Print the vm_map at address.", "[/f] address",NULL) },
    251 	{ DDB_ADD_CMD("module", db_show_module_cmd,	0,
    252 	    "Print kernel modules", NULL, NULL) },
    253 	{ DDB_ADD_CMD("mount",	db_mount_print_cmd,	0,
    254 	    "Print the mount structure at address.", "[/f] address",NULL) },
    255 #ifdef MQUEUE
    256 	{ DDB_ADD_CMD("mqueue", db_show_mqueue_cmd,	0,
    257 	    "Print the message queues", NULL, NULL) },
    258 #endif
    259 	{ DDB_ADD_CMD("mbuf",	db_mbuf_print_cmd,	0,NULL,NULL,
    260 	    "-c prints all mbuf chains") },
    261 	{ DDB_ADD_CMD("ncache",	db_namecache_print_cmd,	0,
    262 	    "Dump the namecache list.", "address",NULL) },
    263 	{ DDB_ADD_CMD("object",	db_object_print_cmd,	0,
    264 	    "Print the vm_object at address.", "[/f] address",NULL) },
    265 	{ DDB_ADD_CMD("page",	db_page_print_cmd,	0,
    266 	    "Print the vm_page at address.", "[/f] address",NULL) },
    267 	{ DDB_ADD_CMD("panic",	db_show_panic,	0,
    268 	    "Print the current panic string",NULL,NULL) },
    269 	{ DDB_ADD_CMD("pool",	db_pool_print_cmd,	0,
    270 	    "Print the pool at address.", "[/clp] address",NULL) },
    271 	{ DDB_ADD_CMD("registers",	db_show_regs,		0,
    272 	    "Display the register set.", "[/u]",NULL) },
    273 	{ DDB_ADD_CMD("sched_qs",	db_show_sched_qs,	0,
    274 	    "Print the state of the scheduler's run queues.",
    275 	    NULL,NULL) },
    276 	{ DDB_ADD_CMD("uvmexp",	db_uvmexp_print_cmd, 0,
    277 	    "Print a selection of UVM counters and statistics.",
    278 	    NULL,NULL) },
    279 #ifdef KERNHIST
    280 	{ DDB_ADD_CMD("kernhist", db_kernhist_print_cmd, 0,
    281 	    "Print the UVM history logs.",
    282 	    NULL,NULL) },
    283 #endif
    284 	{ DDB_ADD_CMD("vnode",	db_vnode_print_cmd,	0,
    285 	    "Print the vnode at address.", "[/f] address",NULL) },
    286 	{ DDB_ADD_CMD("vmem", db_vmem_print_cmd,	0,
    287 	    "Print the vmem usage.", "[/a] address", NULL) },
    288 	{ DDB_ADD_CMD("vmems", db_show_all_vmems,	0,
    289 	    "Show all vmems.", NULL, NULL) },
    290 #ifdef _KERNEL
    291 	{ DDB_ADD_CMD("watches",	db_listwatch_cmd, 	0,
    292 	    "Display all watchpoints.", NULL,NULL) },
    293 #endif
    294 	{ DDB_ADD_CMD(NULL,		NULL,			0,NULL,NULL,NULL) }
    295 };
    296 
    297 static const struct db_command db_command_table[] = {
    298 	{ DDB_ADD_CMD("b",		db_breakpoint_cmd,	0,
    299 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
    300 	{ DDB_ADD_CMD("break",	db_breakpoint_cmd,	0,
    301 	    "Set a breakpoint at address", "[/u] address[,count].",NULL) },
    302 	{ DDB_ADD_CMD("bt",		db_stack_trace_cmd,	0,
    303 	    "Show backtrace.", "See help trace.",NULL) },
    304 	{ DDB_ADD_CMD("c",		db_continue_cmd,	0,
    305 	    "Continue execution.", "[/c]",NULL) },
    306 	{ DDB_ADD_CMD("call",	db_fncall,		CS_OWN,
    307 	    "Call the function", "address[(expression[,...])]",NULL) },
    308 #ifdef _KERNEL	/* XXX CRASH(8) */
    309 	{ DDB_ADD_CMD("callout",	db_show_callout,	0, NULL,
    310 	    NULL,NULL ) },
    311 #endif
    312 	{ DDB_ADD_CMD("continue",	db_continue_cmd,	0,
    313 	    "Continue execution.", "[/c]",NULL) },
    314 	{ DDB_ADD_CMD("d",		db_delete_cmd,		0,
    315 	    "Delete a breakpoint.", "address | #number",NULL) },
    316 	{ DDB_ADD_CMD("delete",	db_delete_cmd,		0,
    317 	    "Delete a breakpoint.", "address | #number",NULL) },
    318 	{ DDB_ADD_CMD("dmesg",	db_dmesg,		0,
    319 	    "Show kernel message buffer.", "[count]",NULL) },
    320 	{ DDB_ADD_CMD("dwatch",	db_deletewatch_cmd,	0,
    321 	    "Delete the watchpoint.", "address",NULL) },
    322 	{ DDB_ADD_CMD("examine",	db_examine_cmd,		CS_SET_DOT,
    323 	    "Display the address locations.",
    324 	    "[/modifier] address[,count]",NULL) },
    325 	{ DDB_ADD_CMD("exit",		db_continue_cmd,	0,
    326 	    "Continue execution.", "[/c]",NULL) },
    327 	{ DDB_ADD_CMD("help",   db_help_print_cmd, CS_OWN|CS_NOREPEAT,
    328 	    "Display help about commands",
    329 	    "Use other commands as arguments.",NULL) },
    330 	{ DDB_ADD_CMD("kill",	db_kill_proc,		CS_OWN,
    331 	    "Send a signal to the process","pid[,signal_number]",
    332 	    "   pid:\t\t\tthe process id (may need 0t prefix for decimal)\n"
    333 	    "   signal_number:\tthe signal to send") },
    334 #ifdef KGDB
    335 	{ DDB_ADD_CMD("kgdb",	db_kgdb_cmd,	0,	NULL,NULL,NULL) },
    336 #endif
    337 	{ DDB_ADD_CMD("machine",NULL,CS_MACH,
    338 	    "Architecture specific functions.",NULL,NULL) },
    339 	{ DDB_ADD_CMD("match",	db_trace_until_matching_cmd,0,
    340 	    "Stop at the matching return instruction.","See help next",NULL) },
    341 	{ DDB_ADD_CMD("next",	db_trace_until_matching_cmd,0,
    342 	    "Stop at the matching return instruction.","[/p]",NULL) },
    343 	{ DDB_ADD_CMD("p",		db_print_cmd,		0,
    344 	    "Print address according to the format.",
    345 	    "[/axzodurc] address [address ...]",NULL) },
    346 	{ DDB_ADD_CMD("print",	db_print_cmd,		0,
    347 	    "Print address according to the format.",
    348 	    "[/axzodurc] address [address ...]",NULL) },
    349 	{ DDB_ADD_CMD("ps",		db_show_all_procs,	0,
    350 	    "Print all processes.","See show all procs",NULL) },
    351 	{ DDB_ADD_CMD("quit",		db_continue_cmd,	0,
    352 	    "Continue execution.", "[/c]",NULL) },
    353 	{ DDB_ADD_CMD("reboot",	db_reboot_cmd,		CS_OWN,
    354 	    "Reboot","0x1  RB_ASKNAME, 0x2 RB_SINGLE, 0x4 RB_NOSYNC, 0x8 RB_HALT,"
    355 	    "0x40 RB_KDB, 0x100 RB_DUMP, 0x808 RB_POWERDOWN",NULL) },
    356 	{ DDB_ADD_CMD("s",		db_single_step_cmd,	0,
    357 	    "Single-step count times.","[/p] [,count]",NULL) },
    358 	{ DDB_ADD_CMD("search",	db_search_cmd,		CS_OWN|CS_SET_DOT,
    359 	    "Search memory from address for value.",
    360 	    "[/bhl] address value [mask] [,count]",NULL) },
    361 	{ DDB_ADD_CMD("set",	db_set_cmd,		CS_OWN,
    362 	    "Set the named variable","$variable [=] expression",NULL) },
    363 	{ DDB_ADD_CMD("show",	NULL, CS_SHOW,
    364 	    "Show kernel stats.", NULL,NULL) },
    365 	{ DDB_ADD_CMD("sifting",	db_sifting_cmd,		CS_OWN,
    366 	    "Search the symbol tables ","[/F] string",NULL) },
    367 	{ DDB_ADD_CMD("step",	db_single_step_cmd,	0,
    368 	    "Single-step count times.","[/p] [,count]",NULL) },
    369 	{ DDB_ADD_CMD("sync",	db_sync_cmd,		CS_OWN,
    370 	    "Force a crash dump, and then reboot.",NULL,NULL) },
    371 	{ DDB_ADD_CMD("trace",	db_stack_trace_cmd,	0,
    372 	    "Stack trace from frame-address.",
    373 	    "[/u[l]] [frame-address][,count]",NULL) },
    374 	{ DDB_ADD_CMD("until",	db_trace_until_call_cmd,0,
    375 	    "Stop at the next call or return instruction.","[/p]",NULL) },
    376 	{ DDB_ADD_CMD("w",		db_write_cmd,		CS_MORE|CS_SET_DOT,
    377 	    "Write the expressions at succeeding locations.",
    378 	    "[/bhl] address expression [expression ...]",NULL) },
    379 	{ DDB_ADD_CMD("watch",	db_watchpoint_cmd,	CS_MORE,
    380 	    "Set a watchpoint for a region. ","address[,size]",NULL) },
    381 	{ DDB_ADD_CMD("whatis",	db_whatis_cmd, 0,
    382 	    "Describe what an address is", "address", NULL) },
    383 	{ DDB_ADD_CMD("write",	db_write_cmd,		CS_MORE|CS_SET_DOT,
    384 	    "Write the expressions at succeeding locations.",
    385 	    "[/bhl] address expression [expression ...]",NULL) },
    386 	{ DDB_ADD_CMD("x",		db_examine_cmd,		CS_SET_DOT,
    387 	    "Display the address locations.",
    388 	    "[/modifier] address[,count]",NULL) },
    389 	{ DDB_ADD_CMD(NULL, 	NULL,		   0, NULL, NULL, NULL) }
    390 };
    391 
    392 static const struct db_command	*db_last_command = NULL;
    393 #if defined(DDB_COMMANDONENTER)
    394 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = ___STRING(DDB_COMMANDONENTER);
    395 #else /* defined(DDB_COMMANDONENTER) */
    396 char db_cmd_on_enter[DB_LINE_MAXLEN + 1] = "";
    397 #endif /* defined(DDB_COMMANDONENTER) */
    398 #define	DB_LINE_SEP	';'
    399 
    400 /*
    401  * Execute commandlist after ddb start
    402  * This function goes through the command list created from commands and ';'
    403  */
    404 static void
    405 db_execute_commandlist(const char *cmdlist)
    406 {
    407 	const char *cmd = cmdlist;
    408 	const struct db_command	*dummy = NULL;
    409 
    410 	while (*cmd != '\0') {
    411 		const char *ep = cmd;
    412 
    413 		while (*ep != '\0' && *ep != DB_LINE_SEP) {
    414 			ep++;
    415 		}
    416 		db_set_line(cmd, ep);
    417 		db_command(&dummy);
    418 		cmd = ep;
    419 		if (*cmd == DB_LINE_SEP) {
    420 			cmd++;
    421 		}
    422 	}
    423 }
    424 
    425 /* Initialize ddb command tables */
    426 void
    427 db_init_commands(void)
    428 {
    429 	static bool done = false;
    430 
    431 	if (done) return;
    432 	done = true;
    433 
    434 	/* register command tables */
    435 	(void)db_register_tbl_entry(DDB_BASE_CMD, &db_base_cmd_builtins);
    436 #ifdef DB_MACHINE_COMMANDS
    437 	(void)db_register_tbl_entry(DDB_MACH_CMD, &db_mach_cmd_builtins);
    438 #endif
    439 	(void)db_register_tbl_entry(DDB_SHOW_CMD, &db_show_cmd_builtins);
    440 }
    441 
    442 
    443 /*
    444  * Add command table to the specified list
    445  * Arg:
    446  * int type specifies type of command table DDB_SHOW_CMD|DDB_BASE_CMD|DDB_MAC_CMD
    447  * *cmd_tbl poiter to static allocated db_command table
    448  *
    449  * Command table must be NULL terminated array of struct db_command
    450  */
    451 int
    452 db_register_tbl(uint8_t type, const struct db_command *cmd_tbl)
    453 {
    454 	struct db_cmd_tbl_en *list_ent;
    455 
    456 	/* empty list - ignore */
    457 	if (cmd_tbl->name == 0)
    458 		return 0;
    459 
    460 	/* force builtin commands to be registered first */
    461 	db_init_commands();
    462 
    463 	/* now create a list entry for this table */
    464 	list_ent = db_zalloc(sizeof(*list_ent));
    465 	if (list_ent == NULL)
    466 		return ENOMEM;
    467 	list_ent->db_cmd=cmd_tbl;
    468 
    469 	/* and register it */
    470 	return db_register_tbl_entry(type, list_ent);
    471 }
    472 
    473 static int
    474 db_register_tbl_entry(uint8_t type, struct db_cmd_tbl_en *list_ent)
    475 {
    476 	struct db_cmd_tbl_en_head *list;
    477 
    478 	switch(type) {
    479 	case DDB_BASE_CMD:
    480 		list = &db_base_cmd_list;
    481 		break;
    482 	case DDB_SHOW_CMD:
    483 		list = &db_show_cmd_list;
    484 		break;
    485 	case DDB_MACH_CMD:
    486 		list = &db_mach_cmd_list;
    487 		break;
    488 	default:
    489 		return ENOENT;
    490 	}
    491 
    492 	TAILQ_INSERT_TAIL(list, list_ent, db_cmd_next);
    493 
    494 	return 0;
    495 }
    496 
    497 /*
    498  * Remove command table specified with db_cmd address == cmd_tbl
    499  */
    500 int
    501 db_unregister_tbl(uint8_t type,const struct db_command *cmd_tbl)
    502 {
    503 	struct db_cmd_tbl_en *list_ent;
    504 	struct db_cmd_tbl_en_head *list;
    505 
    506 	/* find list on which the entry should live */
    507 	switch (type) {
    508 	case DDB_BASE_CMD:
    509 		list=&db_base_cmd_list;
    510 		break;
    511 	case DDB_SHOW_CMD:
    512 		list=&db_show_cmd_list;
    513 		break;
    514 	case DDB_MACH_CMD:
    515 		list=&db_mach_cmd_list;
    516 		break;
    517 	default:
    518 		return EINVAL;
    519 	}
    520 
    521 	TAILQ_FOREACH (list_ent, list, db_cmd_next) {
    522 		if (list_ent->db_cmd == cmd_tbl){
    523 			TAILQ_REMOVE(list,
    524 			    list_ent, db_cmd_next);
    525 			db_free(list_ent, sizeof(*list_ent));
    526 			return 0;
    527 		}
    528 	}
    529 	return ENOENT;
    530 }
    531 
    532 /* This function is called from machine trap code. */
    533 void
    534 db_command_loop(void)
    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 		(void) db_read_line();
    565 		db_command(&db_last_command);
    566 	}
    567 
    568 	db_recover = savejmp;
    569 }
    570 
    571 /*
    572  * Search command table for command prefix
    573  */
    574 static int
    575 db_cmd_search_table(const char *name,
    576 		    const struct db_command *table,
    577 		    const struct db_command **cmdp)
    578 {
    579 
    580 	const struct db_command	*cmd;
    581 	int result;
    582 
    583 	result = CMD_NONE;
    584 	*cmdp = NULL;
    585 
    586 	for (cmd = table; cmd->name != 0; cmd++) {
    587 		const char *lp;
    588 		const char *rp;
    589 
    590 		lp = name;
    591 		rp = cmd->name;
    592 		while (*lp != '\0' && *lp == *rp) {
    593 			rp++;
    594 			lp++;
    595 		}
    596 
    597 		if (*lp != '\0') /* mismatch or extra chars in name */
    598 			continue;
    599 
    600 		if (*rp == '\0') { /* exact match */
    601 			*cmdp = cmd;
    602 			return (CMD_EXACT);
    603 		}
    604 
    605 		/* prefix match: end of name, not end of command */
    606 		if (result == CMD_NONE) {
    607 			result = CMD_PREFIX;
    608 			*cmdp = cmd;
    609 		}
    610 		else if (result == CMD_PREFIX) {
    611 			result = CMD_AMBIGUOUS;
    612 			*cmdp = NULL;
    613 		}
    614 	}
    615 
    616 	return (result);
    617 }
    618 
    619 
    620 /*
    621  * Search list of command tables for command
    622  */
    623 static int
    624 db_cmd_search(const char *name,
    625 	      struct db_cmd_tbl_en_head *list_head,
    626 	      const struct db_command **cmdp)
    627 {
    628 	struct db_cmd_tbl_en *list_ent;
    629 	const struct db_command *found_command;
    630 	bool accept_prefix_match;
    631 	int result;
    632 
    633 	result = CMD_NONE;
    634 	found_command = NULL;
    635 	accept_prefix_match = true;
    636 
    637 	TAILQ_FOREACH(list_ent, list_head, db_cmd_next) {
    638 		const struct db_command *cmd;
    639 		int found;
    640 
    641 		found = db_cmd_search_table(name, list_ent->db_cmd, &cmd);
    642 		if (found == CMD_EXACT) {
    643 			result = CMD_EXACT;
    644 			found_command = cmd;
    645 			break;
    646 		}
    647 
    648 		if (found == CMD_PREFIX) {
    649 			if (accept_prefix_match) {
    650 				/*
    651 				 * Continue search, but note current result
    652 				 * in case we won't find anything else.
    653 				 */
    654 				accept_prefix_match = false;
    655 				result = CMD_PREFIX;
    656 				found_command = cmd;
    657 			} else {
    658 				/*
    659 				 * Watch out for globally ambiguous
    660 				 * prefix match that is not locally
    661 				 * ambiguous - with one match in one
    662 				 * table and another match(es) in
    663 				 * another table.
    664 				 */
    665 				result = CMD_AMBIGUOUS;
    666 				found_command = NULL;
    667 			}
    668 		}
    669 		else if (found == CMD_AMBIGUOUS) {
    670 			accept_prefix_match = false;
    671 			result = CMD_AMBIGUOUS;
    672 			found_command = NULL;
    673 		}
    674 	}
    675 
    676 	*cmdp = found_command;
    677 	return result;
    678 }
    679 
    680 static void
    681 db_cmd_search_failed(char *name, int search_result)
    682 {
    683 	if (search_result == CMD_NONE)
    684 		db_printf("No such command: %s\n", name);
    685 	else
    686 		db_printf("Ambiguous command: %s\n", name);
    687 }
    688 
    689 
    690 /*
    691  * List commands to the console.
    692  */
    693 static void
    694 db_cmd_list(const struct db_cmd_tbl_en_head *list)
    695 {
    696 
    697 	struct db_cmd_tbl_en *list_ent;
    698 	const struct db_command *table;
    699 	size_t		i, j, w, columns, lines, numcmds, width=0;
    700 	const char	*p;
    701 
    702 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
    703 		table = list_ent->db_cmd;
    704 		for (i = 0; table[i].name != NULL; i++) {
    705 			w = strlen(table[i].name);
    706 			if (w > width)
    707 				width = w;
    708 		}
    709 	}
    710 
    711 	width = DB_NEXT_TAB(width);
    712 
    713 	columns = db_max_width / width;
    714 	if (columns == 0)
    715 		columns = 1;
    716 
    717 	TAILQ_FOREACH(list_ent,list,db_cmd_next) {
    718 		table = list_ent->db_cmd;
    719 
    720 		for (numcmds = 0; table[numcmds].name != NULL; numcmds++)
    721 			;
    722 		lines = (numcmds + columns - 1) / columns;
    723 
    724 		for (i = 0; i < lines; i++) {
    725 			for (j = 0; j < columns; j++) {
    726 				p = table[j * lines + i].name;
    727 				if (p)
    728 					db_printf("%s", p);
    729 				if (j * lines + i + lines >= numcmds) {
    730 					db_putchar('\n');
    731 					break;
    732 				}
    733 				if (p) {
    734 					w = strlen(p);
    735 					while (w < width) {
    736 						w = DB_NEXT_TAB(w);
    737 						db_putchar('\t');
    738 					}
    739 				}
    740 			}
    741 		}
    742 	}
    743 	return;
    744 }
    745 
    746 /*
    747  * Read complete command with all subcommands, starting with current
    748  * db_tok_string. If subcommand is missing, print the list of all
    749  * subcommands.  If command/subcommand is not found, print an error
    750  * message.  Returns pointer to "leaf" command or NULL.
    751  */
    752 static const struct db_command *
    753 db_read_command(void)
    754 {
    755 	const struct db_command *command;
    756 	struct db_cmd_tbl_en_head *list;
    757 	int found;
    758 	int t;
    759 
    760 	list = &db_base_cmd_list;
    761 	do {
    762 		found = db_cmd_search(db_tok_string, list, &command);
    763 		if (command == NULL) {
    764 			db_cmd_search_failed(db_tok_string, found);
    765 			db_flush_lex();
    766 			return NULL;
    767 		}
    768 
    769 		if (command->flag == CS_SHOW)
    770 			list = &db_show_cmd_list;
    771 		else if (command->flag == CS_MACH)
    772 			list = &db_mach_cmd_list;
    773 		else if (command->flag == CS_COMPAT)
    774 			/* same list */;
    775 		else
    776 			break; /* expect no more subcommands */
    777 
    778 		t = db_read_token(); /* read subcommand */
    779 		if (t != tIDENT) {
    780 			/* if none given - just print all of them */
    781 			db_cmd_list(list);
    782 			db_flush_lex();
    783 			return NULL;
    784 		}
    785 	} while (list != NULL);
    786 
    787 	return command;
    788 }
    789 
    790 /*
    791  * Parse command line and execute apropriate function.
    792  */
    793 static void
    794 db_command(const struct db_command **last_cmdp)
    795 {
    796 	const struct db_command *command;
    797 	static db_expr_t last_count = 0;
    798 	db_expr_t	addr, count;
    799 	char		modif[TOK_STRING_SIZE];
    800 
    801 	int			t;
    802 	bool		have_addr = false;
    803 
    804 	command = NULL;
    805 
    806 	t = db_read_token();
    807 	if ((t == tEOL) || (t == tCOMMA)) {
    808 		/*
    809 		 * An empty line repeats last command, at 'next'.
    810 		 * Only a count repeats the last command with the new count.
    811 		 */
    812 		command = *last_cmdp;
    813 
    814 		if (!command)
    815 			return;
    816 
    817 		addr = (db_expr_t)db_next;
    818 		if (t == tCOMMA) {
    819 			if (!db_expression(&count)) {
    820 				db_printf("Count missing\n");
    821 				db_flush_lex();
    822 				return;
    823 			}
    824 		} else
    825 			count = last_count;
    826 		have_addr = false;
    827 		modif[0] = '\0';
    828 		db_skip_to_eol();
    829 
    830 	} else if (t == tEXCL) {
    831 		db_fncall(0, 0, 0, NULL);
    832 		return;
    833 
    834 	} else if (t != tIDENT) {
    835 		db_printf("?\n");
    836 		db_flush_lex();
    837 		return;
    838 
    839 	} else {
    840 
    841 		command = db_read_command();
    842 		if (command == NULL)
    843 			return;
    844 
    845 		if ((command->flag & CS_OWN) == 0) {
    846 
    847 			/*
    848 			 * Standard syntax:
    849 			 * command [/modifier] [addr] [,count]
    850 			 */
    851 			t = db_read_token(); /* get modifier */
    852 			if (t == tSLASH) {
    853 				t = db_read_token();
    854 				if (t != tIDENT) {
    855 					db_printf("Bad modifier\n");
    856 					db_flush_lex();
    857 					return;
    858 				}
    859 				/* save modifier */
    860 				strlcpy(modif, db_tok_string, sizeof(modif));
    861 
    862 			} else {
    863 				db_unread_token(t);
    864 				modif[0] = '\0';
    865 			}
    866 
    867 			if (db_expression(&addr)) { /*get address*/
    868 				db_dot = (db_addr_t) addr;
    869 				db_last_addr = db_dot;
    870 				have_addr = true;
    871 			} else {
    872 				addr = (db_expr_t) db_dot;
    873 				have_addr = false;
    874 			}
    875 
    876 			t = db_read_token();
    877 			if (t == tCOMMA) { /*Get count*/
    878 				if (!db_expression(&count)) {
    879 					db_printf("Count missing\n");
    880 					db_flush_lex();
    881 					return;
    882 				}
    883 			} else {
    884 				db_unread_token(t);
    885 				count = -1;
    886 			}
    887 			if ((command->flag & CS_MORE) == 0) {
    888 				db_skip_to_eol();
    889 			}
    890 		}
    891 	}
    892 
    893 	if (command != NULL && command->flag & CS_NOREPEAT) {
    894 		*last_cmdp = NULL;
    895 		last_count = 0;
    896 	} else {
    897 		*last_cmdp = command;
    898 		last_count = count;
    899 	}
    900 
    901 
    902 	if (command != NULL) {
    903 		/*
    904 		 * Execute the command.
    905 		 */
    906 		if (command->fcn != NULL)
    907 			(*command->fcn)(addr, have_addr, count, modif);
    908 
    909 		if (command->flag & CS_SET_DOT) {
    910 			/*
    911 			 * If command changes dot, set dot to
    912 			 * previous address displayed (if 'ed' style).
    913 			 */
    914 			if (db_ed_style)
    915 				db_dot = db_prev;
    916 			else
    917 				db_dot = db_next;
    918 		} else {
    919 			/*
    920 			 * If command does not change dot,
    921 			 * set 'next' location to be the same.
    922 			 */
    923 			db_next = db_dot;
    924 		}
    925 	}
    926 }
    927 
    928 /*
    929  * Print help for commands
    930  */
    931 static void
    932 db_help_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
    933 const char *modif)
    934 {
    935 	const struct db_command *command;
    936 	int t;
    937 
    938 	t = db_read_token();
    939 
    940 	/* is there another command after the "help"? */
    941 	if (t != tIDENT) {
    942 		/* print base commands */
    943 		db_cmd_list(&db_base_cmd_list);
    944 		return;
    945 	}
    946 
    947 	command = db_read_command();
    948 	if (command == NULL)
    949 		return;
    950 
    951 #ifdef DDB_VERBOSE_HELP
    952 	db_printf("Command: %s\n", command->name);
    953 	if (command->cmd_descr != NULL)
    954 		db_printf(" Description: %s\n", command->cmd_descr);
    955 	if (command->cmd_arg != NULL)
    956 		db_printf(" Arguments: %s\n", command->cmd_arg);
    957 	if (command->cmd_arg_help != NULL)
    958 		db_printf(" Arguments description:\n%s\n",
    959 			  command->cmd_arg_help);
    960 	if ((command->cmd_arg == NULL) && (command->cmd_descr == NULL))
    961 		db_printf(" No help message.\n");
    962 #endif
    963 
    964 	db_skip_to_eol();
    965 }
    966 
    967 /*ARGSUSED*/
    968 static void
    969 db_map_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
    970     const char *modif)
    971 {
    972 	bool full = false;
    973 
    974 	if (modif[0] == 'f')
    975 		full = true;
    976 
    977 	if (have_addr == false)
    978 		addr = (db_expr_t)(uintptr_t)db_read_ptr("kernel_map");
    979 
    980 #ifdef _KERNEL
    981 	uvm_map_printit((struct vm_map *)(uintptr_t) addr, full, db_printf);
    982 #endif	/* XXX CRASH(8) */
    983 }
    984 
    985 /*ARGSUSED*/
    986 static void
    987 db_object_print_cmd(db_expr_t addr, bool have_addr,
    988     db_expr_t count, const char *modif)
    989 {
    990 	bool full = false;
    991 
    992 	if (modif[0] == 'f')
    993 		full = true;
    994 
    995 #ifdef _KERNEL /* XXX CRASH(8) */
    996 	uvm_object_printit((struct uvm_object *)(uintptr_t) addr, full,
    997 	    db_printf);
    998 #endif
    999 }
   1000 
   1001 /*ARGSUSED*/
   1002 static void
   1003 db_page_print_cmd(db_expr_t addr, bool have_addr,
   1004     db_expr_t count, const char *modif)
   1005 {
   1006 	bool full = false;
   1007 
   1008 	if (modif[0] == 'f')
   1009 		full = true;
   1010 
   1011 #ifdef _KERNEL /* XXX CRASH(8) */
   1012 	uvm_page_printit((struct vm_page *)(uintptr_t) addr, full, db_printf);
   1013 #endif
   1014 }
   1015 
   1016 /*ARGSUSED*/
   1017 static void
   1018 db_show_all_pages(db_expr_t addr, bool have_addr,
   1019     db_expr_t count, const char *modif)
   1020 {
   1021 
   1022 #ifdef _KERNEL /* XXX CRASH(8) */
   1023 	uvm_page_printall(db_printf);
   1024 #endif
   1025 }
   1026 
   1027 /*ARGSUSED*/
   1028 static void
   1029 db_buf_print_cmd(db_expr_t addr, bool have_addr,
   1030     db_expr_t count, const char *modif)
   1031 {
   1032 	bool full = false;
   1033 
   1034 	if (modif[0] == 'f')
   1035 		full = true;
   1036 
   1037 #ifdef _KERNEL /* XXX CRASH(8) */
   1038 	vfs_buf_print((struct buf *)(uintptr_t) addr, full, db_printf);
   1039 #endif
   1040 }
   1041 
   1042 /*ARGSUSED*/
   1043 static void
   1044 db_event_print_cmd(db_expr_t addr, bool have_addr,
   1045     db_expr_t count, const char *modif)
   1046 {
   1047 	bool showzero = false;
   1048 	bool showall = true;
   1049 	bool showintr = false;
   1050 	bool showtrap = false;
   1051 	bool showmisc = false;
   1052 	struct evcnt ev, *evp;
   1053 	char buf[80];
   1054 	int i;
   1055 
   1056 	i = 0;
   1057 	while (modif[i]) {
   1058 		switch (modif[i]) {
   1059 		case 'f':
   1060 			showzero = true;
   1061 			break;
   1062 		case 'i':
   1063 			showintr = true;
   1064 			showall = false;
   1065 			break;
   1066 		case 't':
   1067 			showtrap = true;
   1068 			showall = false;
   1069 			break;
   1070 		case 'm':
   1071 			showmisc = true;
   1072 			showall = false;
   1073 			break;
   1074 		}
   1075 		i++;
   1076 	}
   1077 
   1078 	if (showall)
   1079 		showmisc = showintr = showtrap = true;
   1080 
   1081 	evp = (struct evcnt *)db_read_ptr("allevents");
   1082 	while (evp != NULL) {
   1083 		db_read_bytes((db_addr_t)evp, sizeof(ev), (char *)&ev);
   1084 		evp = ev.ev_list.tqe_next;
   1085 		if (ev.ev_count == 0 && !showzero)
   1086 			continue;
   1087 		if (ev.ev_type == EVCNT_TYPE_INTR && !showintr)
   1088 			continue;
   1089 		if (ev.ev_type == EVCNT_TYPE_TRAP && !showtrap)
   1090 			continue;
   1091 		if (ev.ev_type == EVCNT_TYPE_MISC && !showmisc)
   1092 			continue;
   1093 		db_read_bytes((db_addr_t)ev.ev_group, ev.ev_grouplen + 1, buf);
   1094 		db_printf("evcnt type %d: %s ", ev.ev_type, buf);
   1095 		db_read_bytes((db_addr_t)ev.ev_name, ev.ev_namelen + 1, buf);
   1096 		db_printf("%s = %lld\n", buf, (long long)ev.ev_count);
   1097 	}
   1098 }
   1099 
   1100 /*ARGSUSED*/
   1101 static void
   1102 db_vnode_print_cmd(db_expr_t addr, bool have_addr,
   1103     db_expr_t count, const char *modif)
   1104 {
   1105 	bool full = false;
   1106 
   1107 	if (modif[0] == 'f')
   1108 		full = true;
   1109 
   1110 #ifdef _KERNEL /* XXX CRASH(8) */
   1111 	vfs_vnode_print((struct vnode *)(uintptr_t) addr, full, db_printf);
   1112 #endif
   1113 }
   1114 
   1115 /*ARGSUSED*/
   1116 static void
   1117 db_vmem_print_cmd(db_expr_t addr, bool have_addr,
   1118     db_expr_t count, const char *modif)
   1119 {
   1120 
   1121 #ifdef _KERNEL /* XXX CRASH(8) */
   1122 	vmem_print((uintptr_t) addr, modif, db_printf);
   1123 #endif
   1124 }
   1125 
   1126 static void
   1127 db_mount_print_cmd(db_expr_t addr, bool have_addr,
   1128     db_expr_t count, const char *modif)
   1129 {
   1130 	bool full = false;
   1131 
   1132 	if (modif[0] == 'f')
   1133 		full = true;
   1134 
   1135 #ifdef _KERNEL	/* XXX CRASH(8) */
   1136 	vfs_mount_print((struct mount *)(uintptr_t) addr, full, db_printf);
   1137 #endif
   1138 }
   1139 
   1140 /*ARGSUSED*/
   1141 static void
   1142 db_mbuf_print_cmd(db_expr_t addr, bool have_addr,
   1143     db_expr_t count, const char *modif)
   1144 {
   1145 
   1146 #ifdef _KERNEL /* XXX CRASH(8) */
   1147 	m_print((const struct mbuf *)(uintptr_t) addr, modif, db_printf);
   1148 #endif
   1149 }
   1150 
   1151 /*ARGSUSED*/
   1152 static void
   1153 db_pool_print_cmd(db_expr_t addr, bool have_addr,
   1154     db_expr_t count, const char *modif)
   1155 {
   1156 
   1157 #ifdef _KERNEL /* XXX CRASH(8) */
   1158 	pool_printit((struct pool *)(uintptr_t) addr, modif, db_printf);
   1159 #endif
   1160 }
   1161 
   1162 /*ARGSUSED*/
   1163 static void
   1164 db_namecache_print_cmd(db_expr_t addr, bool have_addr,
   1165     db_expr_t count, const char *modif)
   1166 {
   1167 
   1168 #ifdef _KERNEL /* XXX CRASH(8) */
   1169 	namecache_print((struct vnode *)(uintptr_t) addr, db_printf);
   1170 #endif
   1171 }
   1172 
   1173 /*ARGSUSED*/
   1174 static void
   1175 db_uvmexp_print_cmd(db_expr_t addr, bool have_addr,
   1176     db_expr_t count, const char *modif)
   1177 {
   1178 
   1179 #ifdef _KERNEL	/* XXX CRASH(8) */
   1180 	uvmexp_print(db_printf);
   1181 #endif
   1182 }
   1183 
   1184 #ifdef KERNHIST
   1185 /*ARGSUSED*/
   1186 static void
   1187 db_kernhist_print_cmd(db_expr_t addr, bool have_addr,
   1188     db_expr_t count, const char *modif)
   1189 {
   1190 
   1191 	kernhist_print(db_printf);
   1192 }
   1193 #endif
   1194 
   1195 /*ARGSUSED*/
   1196 static void
   1197 db_lock_print_cmd(db_expr_t addr, bool have_addr,
   1198     db_expr_t count, const char *modif)
   1199 {
   1200 
   1201 #ifdef _KERNEL	/* XXX CRASH(8) */
   1202 	lockdebug_lock_print((void *)(uintptr_t)addr, db_printf);
   1203 #endif
   1204 }
   1205 
   1206 /*
   1207  * Call random function:
   1208  * !expr(arg,arg,arg)
   1209  */
   1210 /*ARGSUSED*/
   1211 static void
   1212 db_fncall(db_expr_t addr, bool have_addr,
   1213     db_expr_t count, const char *modif)
   1214 {
   1215 #ifdef _KERNEL
   1216 	db_expr_t	fn_addr;
   1217 #define	MAXARGS		11
   1218 	db_expr_t	args[MAXARGS];
   1219 	int		nargs = 0;
   1220 	db_expr_t	retval;
   1221 	db_expr_t	(*func)(db_expr_t, ...);
   1222 	int		t;
   1223 
   1224 	if (!db_expression(&fn_addr)) {
   1225 		db_printf("Bad function\n");
   1226 		db_flush_lex();
   1227 		return;
   1228 	}
   1229 	func = (db_expr_t (*)(db_expr_t, ...))(uintptr_t) fn_addr;
   1230 
   1231 	t = db_read_token();
   1232 	if (t == tLPAREN) {
   1233 		if (db_expression(&args[0])) {
   1234 			nargs++;
   1235 			while ((t = db_read_token()) == tCOMMA) {
   1236 				if (nargs == MAXARGS) {
   1237 					db_printf("Too many arguments\n");
   1238 					db_flush_lex();
   1239 					return;
   1240 				}
   1241 				if (!db_expression(&args[nargs])) {
   1242 					db_printf("Argument missing\n");
   1243 					db_flush_lex();
   1244 					return;
   1245 				}
   1246 				nargs++;
   1247 			}
   1248 			db_unread_token(t);
   1249 		}
   1250 		if (db_read_token() != tRPAREN) {
   1251 			db_printf("?\n");
   1252 			db_flush_lex();
   1253 			return;
   1254 		}
   1255 	}
   1256 	db_skip_to_eol();
   1257 
   1258 	while (nargs < MAXARGS) {
   1259 		args[nargs++] = 0;
   1260 	}
   1261 
   1262 	retval = (*func)(args[0], args[1], args[2], args[3], args[4],
   1263 			 args[5], args[6], args[7], args[8], args[9]);
   1264 	db_printf("%s\n", db_num_to_str(retval));
   1265 #else	/* _KERNEL */
   1266 	db_printf("This command can only be used in-kernel.\n");
   1267 #endif	/* _KERNEL */
   1268 }
   1269 
   1270 static void
   1271 db_reboot_cmd(db_expr_t addr, bool have_addr,
   1272     db_expr_t count, const char *modif)
   1273 {
   1274 #ifdef _KERNEL
   1275 	db_expr_t bootflags;
   1276 
   1277 	/* Flags, default to RB_AUTOBOOT */
   1278 	if (!db_expression(&bootflags))
   1279 		bootflags = (db_expr_t)RB_AUTOBOOT;
   1280 	if (db_read_token() != tEOL) {
   1281 		db_error("?\n");
   1282 		/*NOTREACHED*/
   1283 	}
   1284 	/*
   1285 	 * We are leaving DDB, never to return upward.
   1286 	 * Clear db_recover so that we can debug faults in functions
   1287 	 * called from cpu_reboot.
   1288 	 */
   1289 	db_recover = 0;
   1290 	panicstr = "reboot forced via kernel debugger";
   1291 	cpu_reboot((int)bootflags, NULL);
   1292 #else	/* _KERNEL */
   1293 	db_printf("This command can only be used in-kernel.\n");
   1294 #endif	/* _KERNEL */
   1295 }
   1296 
   1297 static void
   1298 db_sifting_cmd(db_expr_t addr, bool have_addr,
   1299     db_expr_t count, const char *modif)
   1300 {
   1301 	int	mode, t;
   1302 
   1303 	t = db_read_token();
   1304 	if (t == tSLASH) {
   1305 		t = db_read_token();
   1306 		if (t != tIDENT) {
   1307 			bad_modifier:
   1308 			db_printf("Bad modifier\n");
   1309 			db_flush_lex();
   1310 			return;
   1311 		}
   1312 		if (!strcmp(db_tok_string, "F"))
   1313 			mode = 'F';
   1314 		else
   1315 			goto bad_modifier;
   1316 		t = db_read_token();
   1317 	} else
   1318 		mode = 0;
   1319 
   1320 	if (t == tIDENT)
   1321 		db_sifting(db_tok_string, mode);
   1322 	else {
   1323 		db_printf("Bad argument (non-string)\n");
   1324 		db_flush_lex();
   1325 	}
   1326 }
   1327 
   1328 static void
   1329 db_stack_trace_cmd(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
   1330 {
   1331 	register const char *cp = modif;
   1332 	register char c;
   1333 	void (*pr)(const char *, ...);
   1334 
   1335 	pr = db_printf;
   1336 	while ((c = *cp++) != 0)
   1337 		if (c == 'l')
   1338 			pr = (void (*)(const char *, ...))printf;
   1339 
   1340 	if (count == -1)
   1341 		count = 65535;
   1342 
   1343 	db_stack_trace_print(addr, have_addr, count, modif, pr);
   1344 }
   1345 
   1346 static void
   1347 db_sync_cmd(db_expr_t addr, bool have_addr,
   1348     db_expr_t count, const char *modif)
   1349 {
   1350 #ifdef _KERNEL
   1351 	/*
   1352 	 * We are leaving DDB, never to return upward.
   1353 	 * Clear db_recover so that we can debug faults in functions
   1354 	 * called from cpu_reboot.
   1355 	 */
   1356 	db_recover = 0;
   1357 	panicstr = "dump forced via kernel debugger";
   1358 	cpu_reboot(RB_DUMP, NULL);
   1359 #else	/* _KERNEL */
   1360 	db_printf("This command can only be used in-kernel.\n");
   1361 #endif	/* _KERNEL */
   1362 }
   1363 
   1364 /*
   1365  * Describe what an address is
   1366  */
   1367 void
   1368 db_whatis_cmd(db_expr_t address, bool have_addr,
   1369     db_expr_t count, const char *modif)
   1370 {
   1371 	const uintptr_t addr = (uintptr_t)address;
   1372 
   1373 	db_lwp_whatis(addr, db_printf);
   1374 #ifdef _KERNEL	/* XXX CRASH(8) */
   1375 	pool_whatis(addr, db_printf);
   1376 	vmem_whatis(addr, db_printf);
   1377 	uvm_whatis(addr, db_printf);
   1378 	module_whatis(addr, db_printf);
   1379 #endif
   1380 }
   1381