xref: /netbsd-src/sys/ddb/db_variables.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: db_variables.c,v 1.32 2004/09/29 23:54:11 reinoud Exp $	*/
2 
3 /*
4  * Mach Operating System
5  * Copyright (c) 1991,1990 Carnegie Mellon University
6  * All Rights Reserved.
7  *
8  * Permission to use, copy, modify and distribute this software and its
9  * documentation is hereby granted, provided that both the copyright
10  * notice and this permission notice appear in all copies of the
11  * software, derivative works or modified versions, and any portions
12  * thereof, and that both notices appear in supporting documentation.
13  *
14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17  *
18  * Carnegie Mellon requests users of this software to return to
19  *
20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21  *  School of Computer Science
22  *  Carnegie Mellon University
23  *  Pittsburgh PA 15213-3890
24  *
25  * any improvements or extensions that they make and grant Carnegie the
26  * rights to redistribute these changes.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: db_variables.c,v 1.32 2004/09/29 23:54:11 reinoud Exp $");
31 
32 #include "opt_ddbparam.h"
33 
34 #include <sys/param.h>
35 #include <sys/proc.h>
36 #include <uvm/uvm_extern.h>
37 #include <sys/sysctl.h>
38 
39 #include <machine/db_machdep.h>
40 
41 #include <ddb/ddbvar.h>
42 
43 #include <ddb/db_lex.h>
44 #include <ddb/db_variables.h>
45 #include <ddb/db_command.h>
46 #include <ddb/db_sym.h>
47 #include <ddb/db_extern.h>
48 #include <ddb/db_output.h>
49 
50 
51 /*
52  * If this is non-zero, the DDB will be entered when the system
53  * panics.  Initialize it so that it's patchable.
54  */
55 #ifndef DDB_ONPANIC
56 #define DDB_ONPANIC	1
57 #endif
58 int		db_onpanic = DDB_ONPANIC;
59 
60 /*
61  * Can  DDB can be entered from the console?
62  */
63 #ifndef	DDB_FROMCONSOLE
64 #define	DDB_FROMCONSOLE 1
65 #endif
66 int		db_fromconsole = DDB_FROMCONSOLE;
67 
68 /*
69  * Output DDB output to the message buffer?
70  */
71 #ifndef DDB_TEE_MSGBUF
72 #define DDB_TEE_MSGBUF 0
73 #endif
74 int		db_tee_msgbuf = DDB_TEE_MSGBUF;
75 
76 
77 static int	db_rw_internal_variable(const struct db_variable *, db_expr_t *,
78 		    int);
79 static int	db_find_variable(const struct db_variable **);
80 
81 /* XXX must all be ints for sysctl. */
82 const struct db_variable db_vars[] = {
83 	{ "radix",	(void *)&db_radix,	db_rw_internal_variable },
84 	{ "maxoff",	(void *)&db_maxoff,	db_rw_internal_variable },
85 	{ "maxwidth",	(void *)&db_max_width,	db_rw_internal_variable },
86 	{ "tabstops",	(void *)&db_tab_stop_width, db_rw_internal_variable },
87 	{ "lines",	(void *)&db_max_line,	db_rw_internal_variable },
88 	{ "onpanic",	(void *)&db_onpanic,	db_rw_internal_variable },
89 	{ "fromconsole", (void *)&db_fromconsole, db_rw_internal_variable },
90 	{ "tee_msgbuf",	(void *)&db_tee_msgbuf,	db_rw_internal_variable },
91 };
92 const struct db_variable * const db_evars = db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
93 
94 /*
95  * ddb command line access to the DDB variables defined above.
96  */
97 static int
98 db_rw_internal_variable(const struct db_variable *vp, db_expr_t *valp, int rw)
99 {
100 
101 	if (rw == DB_VAR_GET)
102 		*valp = *(int *)vp->valuep;
103 	else
104 		*(int *)vp->valuep = *valp;
105 	return (0);
106 }
107 
108 /*
109  * sysctl(3) access to the DDB variables defined above.
110  */
111 SYSCTL_SETUP(sysctl_ddb_setup, "sysctl ddb subtree setup")
112 {
113 
114 	sysctl_createv(clog, 0, NULL, NULL,
115 		       CTLFLAG_PERMANENT,
116 		       CTLTYPE_NODE, "ddb", NULL,
117 		       NULL, 0, NULL, 0,
118 		       CTL_DDB, CTL_EOL);
119 
120 	sysctl_createv(clog, 0, NULL, NULL,
121 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
122 		       CTLTYPE_INT, "radix",
123 		       SYSCTL_DESCR("Input and output radix"),
124 		       NULL, 0, &db_radix, 0,
125 		       CTL_DDB, DDBCTL_RADIX, CTL_EOL);
126 	sysctl_createv(clog, 0, NULL, NULL,
127 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
128 		       CTLTYPE_INT, "maxoff",
129 		       SYSCTL_DESCR("Maximum symbol offset"),
130 		       NULL, 0, &db_maxoff, 0,
131 		       CTL_DDB, DDBCTL_MAXOFF, CTL_EOL);
132 	sysctl_createv(clog, 0, NULL, NULL,
133 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
134 		       CTLTYPE_INT, "maxwidth",
135 		       SYSCTL_DESCR("Maximum output line width"),
136 		       NULL, 0, &db_max_width, 0,
137 		       CTL_DDB, DDBCTL_MAXWIDTH, CTL_EOL);
138 	sysctl_createv(clog, 0, NULL, NULL,
139 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
140 		       CTLTYPE_INT, "lines",
141 		       SYSCTL_DESCR("Number of display lines"),
142 		       NULL, 0, &db_max_line, 0,
143 		       CTL_DDB, DDBCTL_LINES, CTL_EOL);
144 	sysctl_createv(clog, 0, NULL, NULL,
145 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
146 		       CTLTYPE_INT, "tabstops",
147 		       SYSCTL_DESCR("Output tab width"),
148 		       NULL, 0, &db_tab_stop_width, 0,
149 		       CTL_DDB, DDBCTL_TABSTOPS, CTL_EOL);
150 	sysctl_createv(clog, 0, NULL, NULL,
151 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
152 		       CTLTYPE_INT, "onpanic",
153 		       SYSCTL_DESCR("Whether to enter ddb on a kernel panic"),
154 		       NULL, 0, &db_onpanic, 0,
155 		       CTL_DDB, DDBCTL_ONPANIC, CTL_EOL);
156 	sysctl_createv(clog, 0, NULL, NULL,
157 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
158 		       CTLTYPE_INT, "fromconsole",
159 		       SYSCTL_DESCR("Whether ddb can be entered from the "
160 				    "console"),
161 		       NULL, 0, &db_fromconsole, 0,
162 		       CTL_DDB, DDBCTL_FROMCONSOLE, CTL_EOL);
163 	sysctl_createv(clog, 0, NULL, NULL,
164 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
165 		       CTLTYPE_INT, "tee_msgbuf",
166 		       SYSCTL_DESCR("Whether to tee ddb output to the msgbuf"),
167 		       NULL, 0, &db_tee_msgbuf, 0,
168 		       CTL_DDB, CTL_CREATE, CTL_EOL);
169 }
170 
171 int
172 db_find_variable(const struct db_variable **varp)
173 {
174 	int	t;
175 	const struct db_variable *vp;
176 
177 	t = db_read_token();
178 	if (t == tIDENT) {
179 		for (vp = db_vars; vp < db_evars; vp++) {
180 			if (!strcmp(db_tok_string, vp->name)) {
181 				*varp = vp;
182 				return (1);
183 			}
184 		}
185 		for (vp = db_regs; vp < db_eregs; vp++) {
186 			if (!strcmp(db_tok_string, vp->name)) {
187 				*varp = vp;
188 				return (1);
189 			}
190 		}
191 	}
192 	db_error("Unknown variable\n");
193 	/*NOTREACHED*/
194 	return 0;
195 }
196 
197 int
198 db_get_variable(db_expr_t *valuep)
199 {
200 	const struct db_variable *vp;
201 
202 	if (!db_find_variable(&vp))
203 		return (0);
204 
205 	db_read_variable(vp, valuep);
206 
207 	return (1);
208 }
209 
210 int
211 db_set_variable(db_expr_t value)
212 {
213 	const struct db_variable *vp;
214 
215 	if (!db_find_variable(&vp))
216 		return (0);
217 
218 	db_write_variable(vp, &value);
219 
220 	return (1);
221 }
222 
223 
224 void
225 db_read_variable(const struct db_variable *vp, db_expr_t *valuep)
226 {
227 	int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn;
228 
229 	if (func == FCN_NULL)
230 		*valuep = *(vp->valuep);
231 	else
232 		(*func)(vp, valuep, DB_VAR_GET);
233 }
234 
235 void
236 db_write_variable(const struct db_variable *vp, db_expr_t *valuep)
237 {
238 	int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn;
239 
240 	if (func == FCN_NULL)
241 		*(vp->valuep) = *valuep;
242 	else
243 		(*func)(vp, valuep, DB_VAR_SET);
244 }
245 
246 /*ARGSUSED*/
247 void
248 db_set_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
249 {
250 	db_expr_t	value;
251 	db_expr_t	old_value;
252 	const struct db_variable *vp;
253 	int	t;
254 
255 	t = db_read_token();
256 	if (t != tDOLLAR) {
257 		db_error("Unknown variable\n");
258 		/*NOTREACHED*/
259 	}
260 	if (!db_find_variable(&vp)) {
261 		db_error("Unknown variable\n");
262 		/*NOTREACHED*/
263 	}
264 
265 	t = db_read_token();
266 	if (t != tEQ)
267 		db_unread_token(t);
268 
269 	if (!db_expression(&value)) {
270 		db_error("No value\n");
271 		/*NOTREACHED*/
272 	}
273 	if (db_read_token() != tEOL) {
274 		db_error("?\n");
275 		/*NOTREACHED*/
276 	}
277 
278 	db_read_variable(vp, &old_value);
279 	db_printf("$%s\t\t%s = ", vp->name, db_num_to_str(old_value));
280 	db_printf("%s\n", db_num_to_str(value));
281 	db_write_variable(vp, &value);
282 }
283