xref: /netbsd-src/sys/ddb/db_variables.c (revision 21e37cc72a480a47828990a439cde7ac9ffaf0c6)
1 /*	$NetBSD: db_variables.c,v 1.31 2004/05/25 04:31:48 atatat 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 1.31 2004/05/25 04:31:48 atatat 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 static int	db_rw_internal_variable(const struct db_variable *, db_expr_t *,
69 		    int);
70 static int	db_find_variable(const struct db_variable **);
71 
72 /* XXX must all be ints for sysctl. */
73 const struct db_variable db_vars[] = {
74 	{ "radix",	(void *)&db_radix,	db_rw_internal_variable },
75 	{ "maxoff",	(void *)&db_maxoff,	db_rw_internal_variable },
76 	{ "maxwidth",	(void *)&db_max_width,	db_rw_internal_variable },
77 	{ "tabstops",	(void *)&db_tab_stop_width, db_rw_internal_variable },
78 	{ "lines",	(void *)&db_max_line,	db_rw_internal_variable },
79 	{ "onpanic",	(void *)&db_onpanic,	db_rw_internal_variable },
80 	{ "fromconsole", (void *)&db_fromconsole, db_rw_internal_variable },
81 };
82 const struct db_variable * const db_evars = db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
83 
84 /*
85  * ddb command line access to the DDB variables defined above.
86  */
87 static int
88 db_rw_internal_variable(const struct db_variable *vp, db_expr_t *valp, int rw)
89 {
90 
91 	if (rw == DB_VAR_GET)
92 		*valp = *(int *)vp->valuep;
93 	else
94 		*(int *)vp->valuep = *valp;
95 	return (0);
96 }
97 
98 /*
99  * sysctl(3) access to the DDB variables defined above.
100  */
101 SYSCTL_SETUP(sysctl_ddb_setup, "sysctl ddb subtree setup")
102 {
103 
104 	sysctl_createv(clog, 0, NULL, NULL,
105 		       CTLFLAG_PERMANENT,
106 		       CTLTYPE_NODE, "ddb", NULL,
107 		       NULL, 0, NULL, 0,
108 		       CTL_DDB, CTL_EOL);
109 
110 	sysctl_createv(clog, 0, NULL, NULL,
111 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
112 		       CTLTYPE_INT, "radix",
113 		       SYSCTL_DESCR("Input and output radix"),
114 		       NULL, 0, &db_radix, 0,
115 		       CTL_DDB, DDBCTL_RADIX, CTL_EOL);
116 	sysctl_createv(clog, 0, NULL, NULL,
117 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
118 		       CTLTYPE_INT, "maxoff",
119 		       SYSCTL_DESCR("Maximum symbol offset"),
120 		       NULL, 0, &db_maxoff, 0,
121 		       CTL_DDB, DDBCTL_MAXOFF, CTL_EOL);
122 	sysctl_createv(clog, 0, NULL, NULL,
123 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
124 		       CTLTYPE_INT, "maxwidth",
125 		       SYSCTL_DESCR("Maximum output line width"),
126 		       NULL, 0, &db_max_width, 0,
127 		       CTL_DDB, DDBCTL_MAXWIDTH, CTL_EOL);
128 	sysctl_createv(clog, 0, NULL, NULL,
129 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
130 		       CTLTYPE_INT, "lines",
131 		       SYSCTL_DESCR("Number of display lines"),
132 		       NULL, 0, &db_max_line, 0,
133 		       CTL_DDB, DDBCTL_LINES, CTL_EOL);
134 	sysctl_createv(clog, 0, NULL, NULL,
135 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
136 		       CTLTYPE_INT, "tabstops",
137 		       SYSCTL_DESCR("Output tab width"),
138 		       NULL, 0, &db_tab_stop_width, 0,
139 		       CTL_DDB, DDBCTL_TABSTOPS, CTL_EOL);
140 	sysctl_createv(clog, 0, NULL, NULL,
141 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
142 		       CTLTYPE_INT, "onpanic",
143 		       SYSCTL_DESCR("Whether to enter ddb on a kernel panic"),
144 		       NULL, 0, &db_onpanic, 0,
145 		       CTL_DDB, DDBCTL_ONPANIC, CTL_EOL);
146 	sysctl_createv(clog, 0, NULL, NULL,
147 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
148 		       CTLTYPE_INT, "fromconsole",
149 		       SYSCTL_DESCR("Whether ddb can be entered from the "
150 				    "console"),
151 		       NULL, 0, &db_fromconsole, 0,
152 		       CTL_DDB, DDBCTL_FROMCONSOLE, CTL_EOL);
153 }
154 
155 int
156 db_find_variable(const struct db_variable **varp)
157 {
158 	int	t;
159 	const struct db_variable *vp;
160 
161 	t = db_read_token();
162 	if (t == tIDENT) {
163 		for (vp = db_vars; vp < db_evars; vp++) {
164 			if (!strcmp(db_tok_string, vp->name)) {
165 				*varp = vp;
166 				return (1);
167 			}
168 		}
169 		for (vp = db_regs; vp < db_eregs; vp++) {
170 			if (!strcmp(db_tok_string, vp->name)) {
171 				*varp = vp;
172 				return (1);
173 			}
174 		}
175 	}
176 	db_error("Unknown variable\n");
177 	/*NOTREACHED*/
178 	return 0;
179 }
180 
181 int
182 db_get_variable(db_expr_t *valuep)
183 {
184 	const struct db_variable *vp;
185 
186 	if (!db_find_variable(&vp))
187 		return (0);
188 
189 	db_read_variable(vp, valuep);
190 
191 	return (1);
192 }
193 
194 int
195 db_set_variable(db_expr_t value)
196 {
197 	const struct db_variable *vp;
198 
199 	if (!db_find_variable(&vp))
200 		return (0);
201 
202 	db_write_variable(vp, &value);
203 
204 	return (1);
205 }
206 
207 
208 void
209 db_read_variable(const struct db_variable *vp, db_expr_t *valuep)
210 {
211 	int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn;
212 
213 	if (func == FCN_NULL)
214 		*valuep = *(vp->valuep);
215 	else
216 		(*func)(vp, valuep, DB_VAR_GET);
217 }
218 
219 void
220 db_write_variable(const struct db_variable *vp, db_expr_t *valuep)
221 {
222 	int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn;
223 
224 	if (func == FCN_NULL)
225 		*(vp->valuep) = *valuep;
226 	else
227 		(*func)(vp, valuep, DB_VAR_SET);
228 }
229 
230 /*ARGSUSED*/
231 void
232 db_set_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
233 {
234 	db_expr_t	value;
235 	db_expr_t	old_value;
236 	const struct db_variable *vp;
237 	int	t;
238 
239 	t = db_read_token();
240 	if (t != tDOLLAR) {
241 		db_error("Unknown variable\n");
242 		/*NOTREACHED*/
243 	}
244 	if (!db_find_variable(&vp)) {
245 		db_error("Unknown variable\n");
246 		/*NOTREACHED*/
247 	}
248 
249 	t = db_read_token();
250 	if (t != tEQ)
251 		db_unread_token(t);
252 
253 	if (!db_expression(&value)) {
254 		db_error("No value\n");
255 		/*NOTREACHED*/
256 	}
257 	if (db_read_token() != tEOL) {
258 		db_error("?\n");
259 		/*NOTREACHED*/
260 	}
261 
262 	db_read_variable(vp, &old_value);
263 	db_printf("$%s\t\t%s = ", vp->name, db_num_to_str(old_value));
264 	db_printf("%s\n", db_num_to_str(value));
265 	db_write_variable(vp, &value);
266 }
267