db_command.c revision 118990 
1/*
2 * Mach Operating System
3 * Copyright (c) 1991,1990 Carnegie Mellon University
4 * All Rights Reserved.
5 *
6 * Permission to use, copy, modify and distribute this software and its
7 * documentation is hereby granted, provided that both the copyright
8 * notice and this permission notice appear in all copies of the
9 * software, derivative works or modified versions, and any portions
10 * thereof, and that both notices appear in supporting documentation.
11 *
12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
13 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15 *
16 * Carnegie Mellon requests users of this software to return to
17 *
18 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19 *  School of Computer Science
20 *  Carnegie Mellon University
21 *  Pittsburgh PA 15213-3890
22 *
23 * any improvements or extensions that they make and grant Carnegie the
24 * rights to redistribute these changes.
25 */
26/*
27 *	Author: David B. Golub, Carnegie Mellon University
28 *	Date:	7/90
29 */
30/*
31 * Command dispatcher.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD: head/sys/ddb/db_command.c 118990 2003-08-16 16:57:57Z marcel $");
36
37#include <sys/param.h>
38#include <sys/linker_set.h>
39#include <sys/lock.h>
40#include <sys/mutex.h>
41#include <sys/proc.h>
42#include <sys/reboot.h>
43#include <sys/signalvar.h>
44#include <sys/systm.h>
45#include <sys/cons.h>
46
47#include <ddb/ddb.h>
48#include <ddb/db_command.h>
49#include <ddb/db_lex.h>
50#include <ddb/db_output.h>
51
52#include <machine/cpu.h>
53#include <machine/setjmp.h>
54
55/*
56 * Exported global variables
57 */
58boolean_t	db_cmd_loop_done;
59db_addr_t	db_dot;
60jmp_buf		db_jmpbuf;
61db_addr_t	db_last_addr;
62db_addr_t	db_prev;
63db_addr_t	db_next;
64
65SET_DECLARE(db_cmd_set, struct command);
66SET_DECLARE(db_show_cmd_set, struct command);
67
68static db_cmdfcn_t	db_fncall;
69static db_cmdfcn_t	db_gdb;
70static db_cmdfcn_t	db_kill;
71static db_cmdfcn_t	db_reset;
72
73/* XXX this is actually forward-static. */
74extern struct command	db_show_cmds[];
75
76/*
77 * if 'ed' style: 'dot' is set at start of last item printed,
78 * and '+' points to next line.
79 * Otherwise: 'dot' points to next item, '..' points to last.
80 */
81static boolean_t	db_ed_style = TRUE;
82
83/*
84 * Utility routine - discard tokens through end-of-line.
85 */
86void
87db_skip_to_eol()
88{
89	int	t;
90	do {
91	    t = db_read_token();
92	} while (t != tEOL);
93}
94
95/*
96 * Results of command search.
97 */
98#define	CMD_UNIQUE	0
99#define	CMD_FOUND	1
100#define	CMD_NONE	2
101#define	CMD_AMBIGUOUS	3
102#define	CMD_HELP	4
103
104static void	db_cmd_list(struct command *table, struct command **aux_tablep,
105		    struct command **aux_tablep_end);
106static int	db_cmd_search(char *name, struct command *table,
107		    struct command **aux_tablep,
108		    struct command **aux_tablep_end, struct command **cmdp);
109static void	db_command(struct command **last_cmdp,
110		    struct command *cmd_table, struct command **aux_cmd_tablep,
111		    struct command **aux_cmd_tablep_end);
112
113/*
114 * Search for command prefix.
115 */
116static int
117db_cmd_search(name, table, aux_tablep, aux_tablep_end, cmdp)
118	char *		name;
119	struct command	*table;
120	struct command	**aux_tablep;
121	struct command	**aux_tablep_end;
122	struct command	**cmdp;	/* out */
123{
124	struct command	*cmd;
125	struct command	**aux_cmdp;
126	int		result = CMD_NONE;
127
128	for (cmd = table; cmd->name != 0; cmd++) {
129	    register char *lp;
130	    register char *rp;
131	    register int  c;
132
133	    lp = name;
134	    rp = cmd->name;
135	    while ((c = *lp) == *rp) {
136		if (c == 0) {
137		    /* complete match */
138		    *cmdp = cmd;
139		    return (CMD_UNIQUE);
140		}
141		lp++;
142		rp++;
143	    }
144	    if (c == 0) {
145		/* end of name, not end of command -
146		   partial match */
147		if (result == CMD_FOUND) {
148		    result = CMD_AMBIGUOUS;
149		    /* but keep looking for a full match -
150		       this lets us match single letters */
151		}
152		else {
153		    *cmdp = cmd;
154		    result = CMD_FOUND;
155		}
156	    }
157	}
158	if (result == CMD_NONE && aux_tablep != 0)
159	    /* XXX repeat too much code. */
160	    for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) {
161		register char *lp;
162		register char *rp;
163		register int  c;
164
165		lp = name;
166		rp = (*aux_cmdp)->name;
167		while ((c = *lp) == *rp) {
168		    if (c == 0) {
169			/* complete match */
170			*cmdp = *aux_cmdp;
171			return (CMD_UNIQUE);
172		    }
173		    lp++;
174		    rp++;
175		}
176		if (c == 0) {
177		    /* end of name, not end of command -
178		       partial match */
179		    if (result == CMD_FOUND) {
180			result = CMD_AMBIGUOUS;
181			/* but keep looking for a full match -
182			   this lets us match single letters */
183		    }
184		    else {
185			*cmdp = *aux_cmdp;
186			result = CMD_FOUND;
187		    }
188		}
189	    }
190	if (result == CMD_NONE) {
191	    /* check for 'help' */
192		if (name[0] == 'h' && name[1] == 'e'
193		    && name[2] == 'l' && name[3] == 'p')
194			result = CMD_HELP;
195	}
196	return (result);
197}
198
199static void
200db_cmd_list(table, aux_tablep, aux_tablep_end)
201	struct command *table;
202	struct command **aux_tablep;
203	struct command **aux_tablep_end;
204{
205	register struct command *cmd;
206	register struct command **aux_cmdp;
207
208	for (cmd = table; cmd->name != 0; cmd++) {
209	    db_printf("%-12s", cmd->name);
210	    db_end_line();
211	}
212	if (aux_tablep == 0)
213	    return;
214	for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) {
215	    db_printf("%-12s", (*aux_cmdp)->name);
216	    db_end_line();
217	}
218}
219
220static void
221db_command(last_cmdp, cmd_table, aux_cmd_tablep, aux_cmd_tablep_end)
222	struct command	**last_cmdp;	/* IN_OUT */
223	struct command	*cmd_table;
224	struct command	**aux_cmd_tablep;
225	struct command	**aux_cmd_tablep_end;
226{
227	struct command	*cmd;
228	int		t;
229	char		modif[TOK_STRING_SIZE];
230	db_expr_t	addr, count;
231	boolean_t	have_addr = FALSE;
232	int		result;
233
234	t = db_read_token();
235	if (t == tEOL) {
236	    /* empty line repeats last command, at 'next' */
237	    cmd = *last_cmdp;
238	    addr = (db_expr_t)db_next;
239	    have_addr = FALSE;
240	    count = 1;
241	    modif[0] = '\0';
242	}
243	else if (t == tEXCL) {
244	    db_fncall((db_expr_t)0, (boolean_t)0, (db_expr_t)0, (char *)0);
245	    return;
246	}
247	else if (t != tIDENT) {
248	    db_printf("?\n");
249	    db_flush_lex();
250	    return;
251	}
252	else {
253	    /*
254	     * Search for command
255	     */
256	    while (cmd_table) {
257		result = db_cmd_search(db_tok_string,
258				       cmd_table,
259				       aux_cmd_tablep,
260				       aux_cmd_tablep_end,
261				       &cmd);
262		switch (result) {
263		    case CMD_NONE:
264			db_printf("No such command\n");
265			db_flush_lex();
266			return;
267		    case CMD_AMBIGUOUS:
268			db_printf("Ambiguous\n");
269			db_flush_lex();
270			return;
271		    case CMD_HELP:
272			db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end);
273			db_flush_lex();
274			return;
275		    default:
276			break;
277		}
278		if ((cmd_table = cmd->more) != 0) {
279		    /* XXX usually no more aux's. */
280		    aux_cmd_tablep = 0;
281		    if (cmd_table == db_show_cmds) {
282			aux_cmd_tablep = SET_BEGIN(db_show_cmd_set);
283			aux_cmd_tablep_end = SET_LIMIT(db_show_cmd_set);
284		    }
285
286		    t = db_read_token();
287		    if (t != tIDENT) {
288			db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end);
289			db_flush_lex();
290			return;
291		    }
292		}
293	    }
294
295	    if ((cmd->flag & CS_OWN) == 0) {
296		/*
297		 * Standard syntax:
298		 * command [/modifier] [addr] [,count]
299		 */
300		t = db_read_token();
301		if (t == tSLASH) {
302		    t = db_read_token();
303		    if (t != tIDENT) {
304			db_printf("Bad modifier\n");
305			db_flush_lex();
306			return;
307		    }
308		    db_strcpy(modif, db_tok_string);
309		}
310		else {
311		    db_unread_token(t);
312		    modif[0] = '\0';
313		}
314
315		if (db_expression(&addr)) {
316		    db_dot = (db_addr_t) addr;
317		    db_last_addr = db_dot;
318		    have_addr = TRUE;
319		}
320		else {
321		    addr = (db_expr_t) db_dot;
322		    have_addr = FALSE;
323		}
324		t = db_read_token();
325		if (t == tCOMMA) {
326		    if (!db_expression(&count)) {
327			db_printf("Count missing\n");
328			db_flush_lex();
329			return;
330		    }
331		}
332		else {
333		    db_unread_token(t);
334		    count = -1;
335		}
336		if ((cmd->flag & CS_MORE) == 0) {
337		    db_skip_to_eol();
338		}
339	    }
340	}
341	*last_cmdp = cmd;
342	if (cmd != 0) {
343	    /*
344	     * Execute the command.
345	     */
346	    (*cmd->fcn)(addr, have_addr, count, modif);
347	    db_setup_paging(NULL, NULL, -1);
348
349	    if (cmd->flag & CS_SET_DOT) {
350		/*
351		 * If command changes dot, set dot to
352		 * previous address displayed (if 'ed' style).
353		 */
354		if (db_ed_style) {
355		    db_dot = db_prev;
356		}
357		else {
358		    db_dot = db_next;
359		}
360	    }
361	    else {
362		/*
363		 * If command does not change dot,
364		 * set 'next' location to be the same.
365		 */
366		db_next = db_dot;
367	    }
368	}
369}
370
371/*
372 * 'show' commands
373 */
374
375static struct command db_show_all_cmds[] = {
376#if 0
377	{ "threads",	db_show_all_threads,	0,	0 },
378#endif
379	{ "procs",	db_ps,			0,	0 },
380	{ (char *)0 }
381};
382
383static struct command db_show_cmds[] = {
384	{ "all",	0,			0,	db_show_all_cmds },
385	{ "registers",	db_show_regs,		0,	0 },
386	{ "breaks",	db_listbreak_cmd, 	0,	0 },
387	{ "thread",	db_show_one_thread,	0,	0 },
388#if 0
389	{ "port",	ipc_port_print,		0,	0 },
390#endif
391	{ (char *)0, }
392};
393
394static struct command db_command_table[] = {
395	{ "print",	db_print_cmd,		0,	0 },
396	{ "p",		db_print_cmd,		0,	0 },
397	{ "examine",	db_examine_cmd,		CS_SET_DOT, 0 },
398	{ "x",		db_examine_cmd,		CS_SET_DOT, 0 },
399	{ "search",	db_search_cmd,		CS_OWN|CS_SET_DOT, 0 },
400	{ "set",	db_set_cmd,		CS_OWN,	0 },
401	{ "write",	db_write_cmd,		CS_MORE|CS_SET_DOT, 0 },
402	{ "w",		db_write_cmd,		CS_MORE|CS_SET_DOT, 0 },
403	{ "delete",	db_delete_cmd,		0,	0 },
404	{ "d",		db_delete_cmd,		0,	0 },
405	{ "break",	db_breakpoint_cmd,	0,	0 },
406	{ "dwatch",	db_deletewatch_cmd,	0,	0 },
407	{ "watch",	db_watchpoint_cmd,	CS_MORE,0 },
408	{ "dhwatch",	db_deletehwatch_cmd,	0,      0 },
409	{ "hwatch",	db_hwatchpoint_cmd,	0,      0 },
410	{ "step",	db_single_step_cmd,	0,	0 },
411	{ "s",		db_single_step_cmd,	0,	0 },
412	{ "continue",	db_continue_cmd,	0,	0 },
413	{ "c",		db_continue_cmd,	0,	0 },
414	{ "until",	db_trace_until_call_cmd,0,	0 },
415	{ "next",	db_trace_until_matching_cmd,0,	0 },
416	{ "match",	db_trace_until_matching_cmd,0,	0 },
417	{ "trace",	db_stack_trace_cmd,	0,	0 },
418	{ "where",	db_stack_trace_cmd,	0,	0 },
419	{ "call",	db_fncall,		CS_OWN,	0 },
420	{ "show",	0,			0,	db_show_cmds },
421	{ "ps",		db_ps,			0,	0 },
422	{ "gdb",	db_gdb,			0,	0 },
423	{ "reset",	db_reset,		0,	0 },
424	{ "kill",	db_kill,		CS_OWN,	0 },
425	{ (char *)0, }
426};
427
428static struct command	*db_last_command = 0;
429
430#if 0
431void
432db_help_cmd()
433{
434	struct command *cmd = db_command_table;
435
436	while (cmd->name != 0) {
437	    db_printf("%-12s", cmd->name);
438	    db_end_line();
439	    cmd++;
440	}
441}
442#endif
443
444/*
445 * At least one non-optional command must be implemented using
446 * DB_COMMAND() so that db_cmd_set gets created.  Here is one.
447 */
448DB_COMMAND(panic, db_panic)
449{
450	panic("from debugger");
451}
452
453void
454db_command_loop()
455{
456	/*
457	 * Initialize 'prev' and 'next' to dot.
458	 */
459	db_prev = db_dot;
460	db_next = db_dot;
461
462	db_cmd_loop_done = 0;
463	while (!db_cmd_loop_done) {
464
465	    (void) setjmp(db_jmpbuf);
466	    if (db_print_position() != 0)
467		db_printf("\n");
468
469	    db_printf("db> ");
470	    (void) db_read_line();
471
472	    db_command(&db_last_command, db_command_table,
473		       SET_BEGIN(db_cmd_set), SET_LIMIT(db_cmd_set));
474	}
475}
476
477void
478db_error(s)
479	const char *s;
480{
481	if (s)
482	    db_printf("%s", s);
483	db_flush_lex();
484	longjmp(db_jmpbuf, 1);
485}
486
487
488/*
489 * Call random function:
490 * !expr(arg,arg,arg)
491 */
492static void
493db_fncall(dummy1, dummy2, dummy3, dummy4)
494	db_expr_t	dummy1;
495	boolean_t	dummy2;
496	db_expr_t	dummy3;
497	char *		dummy4;
498{
499	db_expr_t	fn_addr;
500#define	MAXARGS		11	/* XXX only 10 are passed */
501	db_expr_t	args[MAXARGS];
502	int		nargs = 0;
503	db_expr_t	retval;
504	typedef db_expr_t fcn_10args_t(db_expr_t, db_expr_t, db_expr_t,
505			    db_expr_t, db_expr_t, db_expr_t, db_expr_t,
506			    db_expr_t, db_expr_t, db_expr_t);
507	fcn_10args_t	*func;
508	int		t;
509
510	if (!db_expression(&fn_addr)) {
511	    db_printf("Bad function\n");
512	    db_flush_lex();
513	    return;
514	}
515	func = (fcn_10args_t *)fn_addr;	/* XXX */
516
517	t = db_read_token();
518	if (t == tLPAREN) {
519	    if (db_expression(&args[0])) {
520		nargs++;
521		while ((t = db_read_token()) == tCOMMA) {
522		    if (nargs == MAXARGS) {
523			db_printf("Too many arguments\n");
524			db_flush_lex();
525			return;
526		    }
527		    if (!db_expression(&args[nargs])) {
528			db_printf("Argument missing\n");
529			db_flush_lex();
530			return;
531		    }
532		    nargs++;
533		}
534		db_unread_token(t);
535	    }
536	    if (db_read_token() != tRPAREN) {
537		db_printf("?\n");
538		db_flush_lex();
539		return;
540	    }
541	}
542	db_skip_to_eol();
543
544	while (nargs < MAXARGS) {
545	    args[nargs++] = 0;
546	}
547
548	retval = (*func)(args[0], args[1], args[2], args[3], args[4],
549			 args[5], args[6], args[7], args[8], args[9] );
550	db_printf("%#lr\n", (long)retval);
551}
552
553/* Enter GDB remote protocol debugger on the next trap. */
554
555void	  *gdb_arg = NULL;
556cn_getc_t *gdb_getc;
557cn_putc_t *gdb_putc;
558
559static void
560db_gdb (dummy1, dummy2, dummy3, dummy4)
561	db_expr_t	dummy1;
562	boolean_t	dummy2;
563	db_expr_t	dummy3;
564	char *		dummy4;
565{
566
567	if (gdb_arg == NULL) {
568		db_printf("No gdb port enabled. Set flag 0x80 on desired port\n");
569		db_printf("in your configuration file (currently sio only).\n");
570		return;
571	}
572	boothowto ^= RB_GDB;
573
574	db_printf("Next trap will enter %s\n",
575		   boothowto & RB_GDB ? "GDB remote protocol mode"
576				      : "DDB debugger");
577}
578
579static void
580db_kill(dummy1, dummy2, dummy3, dummy4)
581	db_expr_t	dummy1;
582	boolean_t	dummy2;
583	db_expr_t	dummy3;
584	char *		dummy4;
585{
586	db_expr_t old_radix, pid, sig;
587	struct proc *p;
588
589#define DB_ERROR(f)	do { db_printf f; db_flush_lex(); goto out; } while (0)
590
591	/*
592	 * PIDs and signal numbers are typically represented in base
593	 * 10, so make that the default here.  It can, of course, be
594	 * overridden by specifying a prefix.
595	 */
596	old_radix = db_radix;
597	db_radix = 10;
598	/* Retrieve arguments. */
599	if (!db_expression(&sig))
600		DB_ERROR(("Missing signal number\n"));
601	if (!db_expression(&pid))
602		DB_ERROR(("Missing process ID\n"));
603	db_skip_to_eol();
604	if (sig < 0 || sig > _SIG_MAXSIG)
605		DB_ERROR(("Signal number out of range\n"));
606
607	/*
608	 * Find the process in question.  allproc_lock is not needed
609	 * since we're in DDB.
610	 */
611	/* sx_slock(&allproc_lock); */
612	LIST_FOREACH(p, &allproc, p_list)
613	    if (p->p_pid == pid)
614		    break;
615	/* sx_sunlock(&allproc_lock); */
616	if (p == NULL)
617		DB_ERROR(("Can't find process with pid %ld\n", (long) pid));
618
619	/* If it's already locked, bail; otherwise, do the deed. */
620	if (PROC_TRYLOCK(p) == 0)
621		DB_ERROR(("Can't lock process with pid %ld\n", (long) pid));
622	else {
623		psignal(p, sig);
624		PROC_UNLOCK(p);
625	}
626
627out:
628	db_radix = old_radix;
629#undef DB_ERROR
630}
631
632static void
633db_reset(dummy1, dummy2, dummy3, dummy4)
634	db_expr_t	dummy1;
635	boolean_t	dummy2;
636	db_expr_t	dummy3;
637	char *		dummy4;
638{
639
640	cpu_reset();
641}
642